* 21 entries including: US Constitution (series), 3D printing (series), COVID-19 menace (series), gyroplanes in service, COVID-19 versus 1918 flu, LIGO black hole survey, and elite HIV controllers.
* NEWS COMMENTARY FOR NOVEMBER 2020: The big news for the USA in November was the election of Joe Biden as the 46th president of the USA. Of course, as expected, incumbent president Donald Trump has refused to acknowledge defeat, claiming voter fraud and pressing lawsuit after lawsuit -- to see them all dismissed as frivolous.
The election was unsatisfactory to the Democrats, however, in that they lost seats in the House -- though still retained control -- and did not do well in their effort to retake the Senate. It has led to recriminations between the Woke Left and the Moderates in the Democratic Party; the Woke Left insists that Republicans would not have won so readily if the Democrats had campaigned farther to the Left, while the Moderates believe that the Republicans gained because the Democrats seemed too far to the Left.
The Moderates have the much stronger argument, the public having become weary of public demonstrations and the rowdiness that too often accompanies them -- as well as appalled by the "Defund The Police" slogan of the Black Lives Matter movement. Yes, "Defund The Police" is not as extreme in practice as it sounds, but it was senseless to use a slogan that did sound so extreme. The Woke Left has problems understanding that such rhetoric doesn't go over well in, say, West Virginia.
On reflection, the Democrats are exaggerating their own weaknesses, and ignoring the weaknesses of the Republicans. It was certainly an unpleasant surprise that Donald Trump, as appalling as he has been in office, got more votes in 2020 than in 2016 -- but he still lost by a margin close to 10%, and the reality is that it's all steeply downhill for Trump from now on. He will lose his presidential immunity on 20 January 2021, and will be fully exposed to a range of investigations and lawsuits against him.
Along with state charges and civil lawsuits, Trump faces prospective Federal charges, but Joe Biden has been cautious about Federal prosecution against Trump, saying merely that would be up to the attorney general. Although Trump deserves everything bad that he gets, Biden clearly regards him as a distraction, and any attempt to prosecute him at the Federal level may be more trouble than they're worth.
One suggestion that makes a lot of sense is for Congress to create a joint bipartisan independent commission that will investigate accusations against both the Trump and Obama Administrations. If the Republicans refuse to go along, the Democrats could do it on their own -- which the Republicans wouldn't like. The Democrats, on the other side of the coin, would not be unhappy about investigations of the Obama Administration, since any impartial probe into that matter would come up zeroes.
The commission would, in part, act as "truth & reconciliation" commission, getting everybody under suspicion to testify. Trying to prosecute all the malfeasance of the Trump Administration would be impossible; good enough to simply make sure the truth is told. In the end, the independent commission would make recommendations, presumably for changes to laws to avoid repeating trouble in the future. Prosecutions? Unlikely, though dangling the threat of such might encourage people to testify.
No matter what happens, it is hard to believe that Trump will fare well after he leaves office on 20 January 2021. He has been going from fail to fail, and has made too many enemies. His troubles will afflict the Republican Party, which has become the Trump Party, and not to the benefit of the GOP. The stereotypical Trump voter hates politicians, all of them -- and without Trump, the Republican Party has little attraction.
The Republican Party's relationship with Trump was unhealthy, with Republican politicians split into three camps: those who idolized him, those who feared him, and those who cynically saw him as furthering their ends. There has been some active resistance as well, the campaign against Trump notably featuring the efforts of the Lincoln Project -- a gang of anti-Trump conservatives whose motto was: "We go low so you don't have to."
In sum, Trump highlighted the instability of the GOP. In the post-Trump; era, the Republicans will be split between those who want to "keep on Trumpin'", and those who want to repudiate Trump. It will be difficult to maintain solidarity. Joe Biden, it seems, never expected to have control of the Senate, at least not right away, and appears inclined to exploit division in the Republican Party.
* In the meantime, Trump is still refusing to acknowledge his electoral defeat, though he is no longer trying to hold up the transition of power. He had been flooding state courts with nuisance lawsuits; in response to one such lawsuit, Michigan Judge Cynthia Stevens told a Trump lawyer:
BEGIN QUOTE:
What I have, at best, is a hearsay affidavit. If there is something in that affidavit that would indicate that the [witness] observed activity that would be a deprivation of the rights of poll watchers, I want you to please focus my attention on that. "I heard somebody else say something." Tell me why that's not hearsay. Come on now.
END QUOTE
The Trump apparatus set up a voter-fraud hotline, with the Lincoln Project suggesting: "In their time of crisis, calling 1-888-630-1776 would distract them from their vital work. So please don't call 1-888-630-1776." Of course, the hotline got spammed to death.
The last act was a frantic attempt to get the Republicans in Michigan to overturn the state's electors, with Trump inviting Michigan GOP to the White House. The exercise made everyone nervous, but cooler heads pointed out that the idea was preposterous -- Biden took Michigan by a six-figure margin, and the state GOP didn't really have the power to overturn the electors. It fizzled, the state certified its vote, and that was effectively the end of it. The stand for Joe Biden's inauguration is now being built in front of the White House.
Trump seems uncharacteristically deflated. He's talking about big plans for starting a TV channel, or running for president in 2024 -- the better to milk his fans for campaign contributions -- but he has little prospect of anything but continued collapse. As for running in 2024, it isn't a good bet that he'll live that long; if he does, he'll be even less functional than he is now, which is saying a lot.
What really happens next? Who knows? All that's obvious is that 2021 will be a very chaotic year. It pays to wait to see what the landscape will be like in 2022. It may look much more promising.
* One of top items on Joe Biden's agenda is climate change. As discussed in an article from NATURE.com ("Can Joe Biden Make Good On His Revolutionary Climate Agenda?" by Jeff Tollefson, 25 November 2020), even though Biden faces a split Congress, he has tools at his disposal to take strong action. Vicki Arroyo -- executive director of Georgetown University's Climate Center in Washington DC -- says: "This is really the first time that a US president is leading with climate." That's exciting, she adds, but she suggests cautious optimism: global warming is still a partisan issue on Capitol Hill, and "that is going to limit what Biden can accomplish".
Trump is a climate-change denier, having pulled the USA out of the Paris climate agreement. He was on a wrong-way street; now other players, from China to the European Union, are preparing to present a new round of commitments at the United Nations climate conference in Glasgow, Scotland, in 2021. Biden has already made it clear that the USA will come back to the climate accord and climate discussions. On 23 November, Biden named John Kerry as his special envoy for climate change and gave him a seat on the White House National Security Council. Kerry had served as secretary of state under Obama, and was key to mediating the original Paris Agreement.
Biden's first opportunity to advance his agenda through Congress could, as with Obama, come in the form of an economic stimulus bill. With the US economy staggering from the pandemic, many analysts expect this to be at the top of Biden's agenda when he enters office. His team has made climate a central feature of the administration's economic plan, and could leverage a stimulus package to increase Federal investments in low-carbon energy and green infrastructure.
It is unlikely that Biden will be able to establish anything like a "Green New Deal", but he still has options. Despite their inclination to deny climate change, Republicans are not all that down on renewable energy -- wind power has saved the livelihoods of many farmers in Red states -- and may not necessarily be hostile to climate action, if carefully presented. One important thing to do is to establish a carbon tax. One proposal suggested by the Climate Leadership Council -- a non-profit organization based in Washington DC, would start with a modest $40 USD per tonne tax on carbon dioxide emissions that would increase over time, with the goal of cutting US emissions in half by 2035. The proceeds would be refunded back to taxpayers.
How easy it will be to get a carbon tax through the Senate is impossible to say in the disordered political landscape, but failing that, there's still much Biden could do via executive action:
Tim Profeta -- who leads Duke University's Nicholas Institute for Environmental Policy Solutions in Durham, North Carolina -- says: "There's no need for Biden to wait. There's a lot the president can do using his own authority, starting from day one."
Profeta co-chairs the Climate 21 Project, an independent group of academics, policy specialists and former government officials that has drawn up a blueprint for executive action across eleven Federal offices and agencies to deal with global warming. The headline recommendation from the group, which already is connected to Biden's transition team, is that the new administration should establish a "National Climate Council" led by an official that reports directly to the president. This person would help to advance Biden's climate agenda by coordinating with various US agencies. Profeta says: "You need somebody in the West Wing who has the president's ear, and who is focused on making climate action happen across the Federal government."
The biggest hammer the president has when it comes to climate change is regulating greenhouse-gas emissions directly through the EPA. Over the past four years, Trump's EPA has reversed or weakened dozens of environmental regulations, including a trio of Obama-era climate policies targeting emissions from vehicles, power plants, and oil and gas facilities. Biden is expected to immediately move to restore and strengthen those efforts -- but that promises to be a lot of work, and it's important for the Biden Administration to figure out the most effective way to tackle the problem.
In the case of the policy on fuel-efficiency standards for vehicles, the administration might move forward with an entirely new rule. The Trump administration rolled back standards put in place under Obama so that the car industry has to boost average fuel efficiency by only around 1.5% per year between 2022 and 2025, instead of 5% per year. Instead of simply changing the rule again, the Biden Administration will likely develop an entirely new set of regulations that look forward another 10:15 years for longer-lasting impact.
One outstanding question is how to deal with the power sector, which accounts for more than a quarter of US emissions. The Trump administration replaced Obama's Clean Power Plan -- which never went into effect owing to court challenges -- with what amounted to a non-program, Trump being focused on bringing back coal power. It didn't work. Thanks in part to state and local regulation as well as simple momentum, cheap natural gas and renewables such as wind and solar, combined with long-standing pollution regulations, have put many coal-fired power plants out of business. As a result, US carbon emissions from the power sector were nearly 33% below 2005 levels in 2019, surpassing Obama's goals eleven years early. A new Clean Power Plan is an obvious path for the Biden Administration, the challenge being to get it through the courts.
Of course, the first thing to do will be to re-integrate the USA into the Paris climate agreement -- but that in itself is not enough: the USA has to take a global leadership role. The Biden Administration will need to devise a climate pledge and announce it to the world at the 2021 conference in Glasgow, where countries are expected to update their commitments for the first time since the agreement was signed in 2015. Under Obama, the United States initially committed to cut greenhouse-gas emissions by at least 26% below 2005 levels by 2025.
Joseph Aldy -- an economist at Harvard University in Cambridge, Massachusetts, who served as a White House climate adviser under Obama -- says that the challenge is to make sure the new US pledge is both strong and credible: "We have lost credibility on many fronts as a result of Donald Trump." The Biden Administration will have to establish a robust program that will be sustained by future administrations. Aldy says: "Our counterparts around the world will be looking very closely at what we are doing."
Bob Inglis -- previously a Republican member of the House of Representatives from South Carolina, now head of the Energy and Enterprise Initiative at George Mason University in Fairfax, Virginia, which is a think tank that advocates politically conservative environmental solutions -- believes that Biden's working-class roots and his decades of negotiating across the political aisle in the Senate make him the best man to take on MISSION IMPOSSIBLE, Inglis saying: "Joe Biden was made for this moment. He's a centrist who knows how to operate within the system, and that's what I'm putting my confidence in at this point."
BACK_TO_TOP* AMERICA'S CONSTITUTION (127): Gerald Ford inherited a weak economy from Richard Nixon and it remained weak, inflation continuing to be a problem -- indeed, being seen as more a problem than rising unemployment, on the basis that fixing inflation would increase employment. Not long after Ford took office, at the end of September 1974, he signed an executive order to establish an "Economic Policy Board". He also went public with a "Whip Inflation Now (WIN)" effort, asking Americans to scale back consumption, with over a hundred thousand "WIN" buttons distributed to Americans who mailed in a WIN pledge.
WIN was widely seen as the gimmick it was. More practically, in 1974 Ford requested a 5% income tax increase on corporations and wealthy individuals, and proposed to cut Federal spending by $4.4 billion, to under $300 billion. In 1975, when the country was clearly in recession, Ford dropped the request for a tax increase and focused on cutting taxes to stimulate growth; Congress authorized even bigger tax cuts, with Ford signing the "Tax Reduction Act of 1975" -- which led to large, by the standards of the time, Federal deficits in 1975 and 1976. When, in 1975, New York City faced bankruptcy and asked the Federal government for help, Ford said he would veto any bill that gave NYC a bailout. The NEW YORK DAILY NEWS ran the headline: "Ford to City: Drop Dead".
On 5 February 1976, an army recruit at Fort Dix, New Jersey, died of what seems an H1N1 influenza virus strain that had jumped from pigs to humans; four other soldiers were hospitalized. Public health officials promoted a national vaccination campaign -- which was duly implemented, to prove something of a fiasco: there were stumbles in the mass vaccinations, and the feared flu pandemic did not materialize. The program was ended in December 1976 after a quarter of Americans had been vaccinated. The legacy of the swine flu vaccination program was ambiguous, doing nothing to prove whether it was an over-reaction or not.
Ford supported the ERA, issuing a proclamation in 1975:
BEGIN QUOTE:
In this Land of the Free, it is right, and by nature it ought to be, that all men and all women are equal before the law. Now, therefore, I, Gerald R. Ford, President of the United States of America, to remind all Americans that it is fitting and just to ratify the Equal Rights Amendment adopted by the Congress of the United States of America, in order to secure legal equality for all women and men, do hereby designate and proclaim August 26, 1975, as Women's Equality Day.
END QUOTE
However, as for reproductive rights, Ford supported "a Federal constitutional amendment that would permit each one of the 50 States to make the choice". That was bluntly saying: "Overturn ROE V. WADE." It was a legal nonstarter, saying that abortion could be criminalized in one state, but not in a neighboring state -- and a half-step towards criminalizing it in all states. He was embarrassed in 1975 when, during an interview, his wife Betty called ROE V. WADE a "great, great decision." Late in his life, Ford would say he identified as "pro-choice", and say, in effect, that the abortion issue wasn't the hill Republicans should die on. [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* WINGS & WEAPONS: As discussed by an article from JANES.com ("Portugal Joins Brazilian ATL-100 Aircraft Project" "26 May 2020), the Brazilian firm Desenvolvimento Aeronautico (DESAER) is now teaming up with the Portuguese Center Of Engineering And Product Development (CEIIA)" to develop the ATL-100 lightweight twin-turboprop multirole aircraft.
As currently envisioned, the baseline ATL-100 will be of conventional utility-cargo configuration, with a high straight wing mounting the turboprops, a tee tail with a swept tailfin and a forward fillet, fixed tricycle landing gear, a rear loading ramp, an entry door on the forward left fuselage, and an emergency exit on each side. The ATL-100 will have a 7,500-kilogram (16,540-pound) maximum operating weight with a maximum payload of 2,500 kilograms (5,510 pounds), a length of 16 meters (52.5 feet), a wingspan of 20 meters (65.6 feet), and a height of 6 meters (20 feet). Cruise speed will be 430 KPH (265 MPH / 230 KT), with a service ceiling of 7,620 meters (25,000 feet) and a range of 570 kilometers (355 miles / 305 NMI) when fully loaded.
The ATL-100 will be available in civil and military variants. The military version will perform roles such as troop transport, logistics support, search and rescue, paratroop airdrop, maritime patrol, liaison, border surveillance, medical evacuation, and special missions.
* As discussed by an article from JANES.com ("Talon-A Hypersonic Testbed To Achieve IOC By 2022" by Akshara Parakala & Aditya Jadhav, 24 April 2020), Seattle-based startup company is now driving forward on development of the firm's privately-funded "Talon-A" hypersonic testbed. It is to go into operation in 2022.
Talon-A is an air-launched, unpiloted, reusable air vehicle, capable of long-duration flights at speeds greater than Mach 6. It will have a launch weight of about 2,770 kilograms (6,110 pounds), a length of 8.5 meters (27.9 feet), and a wingspan of 3.4 meters (11.15 meters). It is of "waverider" configuration, obtaining lift from its own shockwaves, with highly-swept delta wings and a single tailfin. Details of the propulsion system have not announced, company officials saying it was powered by an "air-breathing rocket", which sounds like a solid-fuel ramjet.
* As discussed by an article from JANES.com ("France Launches Concept Study For A Stratobus-Type HAPS" by Emmanuel Huberdeau, 15 January 2020 RSS, the French defense procurement agency "Direction Generale de l'Armement (DGA)" has awarded a contract to Thales and Thales Alenia Space for a study of using their "Stratobus" high-altitude drone airship to conduct intelligence, surveillance, and reconnaissance (ISR) operations.
Stratobus is a stratospheric "high altitude pseudo satellite (HAPS)", intended to fly above 20 kilometers (65,000 feet) for missions including ISR and communications for both civilian and military purposes. The study initiated by DGA will include an operational concept study for an ISR mission, including exercises simulating its use in theatres of operation. A full-scale demonstrator concept will also be studied.
The Stratobus concept was first introduced by Thales in 2014, with the program being formally launched in 2016. Flight demonstrations are planned for late 2023. As originally defined, the Stratobus airship will be 115 meters (254 feet) long, and weigh almost 7,000 kilograms (15,435 pounds). In normal configuration, it will be able to carry 250 kilograms (550 pounds) of payload, with a power supply of 5 kilowatts. Under optimum conditions, it could carry 450 kilograms (990 pounds) of payload, with a power supply of 8 kW. It will be able to operate for five years, with annual servicing.
COMMENT ON ARTICLE* ADVANCES IN 3D PRINTING (4): 3D printing is also evolving into "4D printing", meaning 3D-printed items that can perform some mechanical action. 4D-printed objects often incorporate "shape-memory polymers" -- materials that can react to changes in their environment, such as heat or moisture.
In 2018, researchers at the Swiss Federal Institute of Technology (ETH) in Zurich and the California Institute of Technology in Pasadena reported printing a submarine that propels itself forward using paddles that snap backwards when placed in warm water. The work could lead to microrobots that can explore the oceans autonomously. The problem is that the paddles must be reset after each stroke; battery-operated actuators could reset the paddles, but that would make the machine less efficient.
Another approach to 4D-printed devices involves initiating the action with a changing external magnetic field. US researchers have 3D-printed lattice structures filled with a liquid that changes stiffness in response to a magnetic field. One application might to help car seats stiffen on impact.
Other, more passive potential 4D printing applications include stents, which could be compressed to be implanted then expanded on reaching the desired site in a blood vessel to prop it open. In 2019, researchers in Switzerland and Italy described a 4D-printed stent that is just 50 micrometers wide, much smaller than existing stents ones. The devices are so small, the researchers says, they might be used to treat complications in fetuses, such as strictures in the urinary tract, which can sometimes be fatal.
Possibly the most ambitious field in 3D printing is the fabrication of tissues and organs. Currently, techniques for such bioprinting can print tissue such as human skin that is suitable for lab research, as well as patches of tissue for livers and other organs that have been successfully implanted in rats. However, such techniques are still far from ready to use in a human body. Researchers dream of printing fully functioning organs that could mean the end of long wait lists for organ donors. Harvard's Jennifer Lewis says: "I personally feel we're a decade-plus away from that, at least, if ever."
Over the shorter term, there is a lot of work printing items that move or change by printing multiple materials together. Monash's Timothy Scott says: "That's absolutely where the field is heading." In 2019, Lewis and her lab described a printer that can quickly switch between different polymer inks, or mix them, as it prints a single object. That means objects can be printed with both flexible and rigid parts. Lewis has spun off previous work on multi-material printers into a firm named "Voxel8", a start-up in Somerville, Massachusetts. Her multi-material printer is well-suited to fabricating athletic gear; wearable devices need to be flexible around joints while also having rigid parts to house electronics.
In 2018, a team led by Jerry Qi -- a materials engineer at Georgia Institute of Technology in Atlanta -- unveiled a "four-in-one" printer. This device combines a nozzle that extrudes molten polymer with one that prints light-sensitive resin, ready to be cured by ultraviolet lamps or lasers, along with two that print wires and circuitry from tiny dots of metal. The print heads work together to make integrated devices with circuits embedded on a rigid board, or inside a flexible polymer enclosure.
It wasn't as simple as bolting four different printers into one platform: the researchers also needed to develop software that would allow each print head to communicate with the others and keep track of progress. Qi says his group is now working with electronics companies interested in printing circuit-board prototypes faster than conventional methods.
The field is still far from delivering on early visions of bringing mass manufacturing into people's homes. For now, honestly useful printers are too expensive to appeal to non-specialists. However, 3D printing has come a long way in the past 20 years. Iain Todd of the University of Sheffield remembers people touring his lab in the early 2000s to see his technique to fuse specks of metal dust together to grow parts. Compared with the conventional milling machines and metal-cutting systems in neighboring labs, his 3D-printing machines struck visitors as a curiosity: "It was like we were some sort of a dog playing a piano in a bar." Now, such techniques are in commercial use, and the technology continues to expand its footprint. [END OF SERIES]
START | PREV | COMMENT ON ARTICLE* GYROPLANES PERSIST: The "autogyro" AKA "gyrocopter" or "gyroplane" is an ancestor of the helicopter. It looks like a prop-powered airplane with a rotor instead of wings; the rotor is unpowered, spinning from the air flowing up underneath it, and keeping the machine aloft. Gyroplanes have been around for going on a century, but in modern times they haven't seen as very practical, being mostly flown by enthusiasts and hobbyists. According to an article from AIR INTERNATIONAL ("Special Services By Gyrocopter" by Guy Martin, September 2020), in the 21st century, the gyroplane seems to be starting to catch on for serious use.
Gyroplanes are now being used in governmental roles in China, Burkina Faso, Iran, Kenya, Kurdistan, Senegal, and South Africa. Militaries have experimented with them in for use in special operations; in paramilitary roles, they are also used for border patrol, wildlife protection, and police.
Wagtail Aviation of South Africa produces the two-seat "Trojan", which can carry up to 450 kilograms (1,000 pounds) of payload. It can be fitted with a weapons beam, and has been evaluated with twin 7.62-millimeter machine guns, a nine-round rocket-propelled grenade launcher, and a belt-fed 40-millimeter grenade launcher. It is powered by a turbocharged Subaru piston engine that provides 195 kW (260 HP), driving a pusher propeller. Although the rotor is not driven in flight by the engine, it can be "spun up" while still on the ground to permit short take-offs. Wagtail wants to increase the redline power on the spin-up to permit vertical take-offs. It has fat balloon tires for operation on dirt roads and other rough airstrips.
The Trojan has a top speed of 210 KPH (130 MPH), and a range of 500 to 700 kilometers (310 to 430 miles), depending on fuel tank size. Wagtail is working on a drone version of the Trojan, and has also developed a three-seat "Trooper" gyroplane, with a maximum take-off weight of 900 kilograms (2,000 pounds). So far, strictly military use of the Trojan has been limited to evaluations.
The "Lieying" gyroplane, from the Chinese company Shaanxi Baoji He Defense Technology, has been flown by the Chinese People's Liberation Army. The baseline Lieyang has two tandem seats, an empty weight of 290 kilograms (1,235 pounds) and is powered by a Rotax 914 flat-four water-cooled engine with 85 kW (115 HP). The Lieyang can carry a useful load of 270 kilograms (595 pounds). It can be fitted with skis for operation on snow, and floats for operation on water. It has been evaluated carrying light guided munitions -- in the class of those generally carried by drones -- and fitted with a sensor / targeting turret.
A larger version, the "Falcon", with three seats -- one in front, two across the back -- has also been flown. It has increased empty weight, wider rotor blades, and an uprated engine with 100 kW (135 HP). It is not clear if the PLA has flown these machines operationally, or just for evaluation. However, gyroplanes are clearly in government service in a number of countries:
There are tales of gyroplanes in Iranian military service, but the details are not clear. In any case, gyroplanes are now seeing expanded use, with the prospect of further growth.
COMMENT ON ARTICLE* THE COVID-19 MENACE (20): As discussed by an article from SCIENCEMAG.org ("The Pandemic Virus Is Slowly Mutating. But Is It Getting More Dangerous?" by Kai Kupferschmidt, 14 July 2020), viruses are always mutating, some more readily than others. Right now, we don't have a clear idea of how mutable the SARS-CoV-2 virus really is. [ED: Now it appears the answer is: not all that much, fortunately.]
At some time in the COVID-19 pandemic, one of the 30,000 base pairs in the genome of SARS-CoV-2 changed from an "A" to a "G". Today, that mutation, at position 23,403, has spread around the world, to be found in the great majority of newly sequenced viruses. The puzzle is: does that mutation help the virus spread faster, so it overwhelms other strains? Or is it just along for the ride?
Having passed a half year into the pandemic, it is not clear if the virus will evolve to become nastier -- or, if we're really lucky, become more benign. The uncertainty is partly because SARS-CoV-2 mutates slowly. That's fortunate; viruses like HIV that mutate rapidly are extremely hard to defeat. On considering that issue, virologists have raised another one: what if SARS-CoV-2 was well-adapted to human hosts well before it exploded over the world?
On average, sequencing SARS-CoV-2 samples shows the coronavirus accumulates about two changes per month in its genome. Most of the changes don't affect how the virus behaves, but a few may change the disease's transmissibility or severity. One of the first worrisome changes was the wholesale deletion of 382 base pairs in a gene named ORF8, whose function is unknown. The deletion was first reported by Wang Linfa and others at the Duke-NUS Medical School in Singapore, to then be reported from Taiwan as well.
A deletion in the same gene occurred early in the 2003 SARS outbreak; lab experiments later showed that variant replicates less efficiently than its parent, suggesting the mutation may have slowed the SARS epidemic. Wang says cell culture experiments suggest the mutation does not have the same benign effect in SARS-CoV-2, "but there are indications that it may cause milder disease in patients."
The mutation at position 23,403 has attracted the most attention, in part because it changed the virus' "spike", the protein on its surface that attaches to human cells. The mutation changed the amino acid at position 614 of the spike from an aspartic acid (abbreviated "D") to a glycine ("G"), which is why it's called "G614".
Bette Korber and colleagues at Los Alamos National Laboratory have shown that G614 has become more common in almost every place around the world that they looked at, while the earlier "D614" is generally gone. That hints that it's out-competed by G614, but it might just be a coincidence. Kristian Andersen, a computational biologist at Scripps Research, says: "Any one mutation may rise to very high frequency across the world, just because of random chance. This happens all the time."
Tracking the spread of different viral variants carrying the two mutations could show what's happening. The United Kingdom's COVID-19 Genomics Consortium has sequenced 30,000 SARS-CoV-2 genomes, allowing scientists to compare how fast 43 lineages carrying the G614 mutation and 20 with D614 spread. They estimated that the former grew 1.22 times faster than the latter, but the statistical significance was low. Andrew Rambaut, an evolutionary biologist at the University of Edinburgh in Scotland, says: "Evidence for a difference is weak, and if it does exist, the estimated effect is moderate." [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* AMERICA'S CONSTITUTION (126): After pardoning Nixon, Gerald Ford tended to avoid mentioning his name, instead referring to him in public as "my predecessor" or "the former president". When queried by a reporter as to why he didn't mention Nixon by name, Ford said: "I just can't bring myself to do it."
Ford was inclined to privately justify his decision by citing the 1915 SCOTUS decision in BURDICK V. UNITED STATES -- an interesting but obscure judgement. The newspaper THE NEW YORK TRIBUNE had printed information leaked from the Treasury Department. When the authorities tried to determine who had leaked the information to George Burdick, an editor of the paper, pleaded the 5th Amendment and would not say who it was. President Wilson offered Burdick a pardon in an attempt to get him to testify, but Burdick rejected the pardon. Pleading the 5th didn't help him; he was fined and jailed for contempt. The court ruled that Burdick was under no legal obligation to accept the pardon, and it was not in effect if he didn't accept it. Ford pointed to a comment in the decision, written by Justice Joseph McKenna, to suggest that pardoning Nixon did not exonerate him:
BEGIN QUOTE:
This brings us to the differences between legislative immunity and a pardon. They are substantial. The latter carries an imputation of guilt; acceptance a confession of it. The former has no such imputation or confession.
END QUOTE
Shortly after pardoning Nixon, on 16 September, Ford issued "Presidential Proclamation 4313", which set up a conditional amnesty program for military deserters and draft dodgers who had left the USA, mostly to Canada. The program for the "Return of Vietnam Era Draft Evaders & Military Deserters" required that returnees re-pledge allegiance to the USA, and perform public service. A "Clemency Board" was set up for oversight.
Of course, on assuming office, Ford inherited Nixon's cabinet, but he would replace everyone in it, except for Secretary of State Kissinger and Treasury Secretary William E. Simon. The biggest purge was in the fall of 1975, being known as "Ford's Halloween Massacre".
One of Ford's appointees, William Coleman, the Secretary of Transportation, was the first black cabinet secretary appointed by a Republican administration. He was actually the second black man to become a cabinet secretary, the first being Robert Weaver, LBJ's Secretary of Housing & Urban Development.
Ford's transition chairman and first Chief of Staff was former congressman and ambassador Donald Rumsfeld. Ford named Rumsfeld as his defense secretary in 1975, with Rumsfeld becoming the youngest secretary of defense ever. Ford replaced him as chief of staff with a young Wyoming politician named Dick Cheney.
Ford had barely got settled in the Oval Office when the 1974 mid-term elections came around. Given the public dissatisfaction with Nixon, they didn't go well for the Republicans; the Democrats gained 49 seats from the Republicans, increasing the Democrat majority to 291 of the 435 seats, providing a vital two-thirds majority. Even Ford's previous House seat, traditionally seen as reliably Republican, went Democrat. The Democrats also gained in the Senate, with 61 seats -- not quite a two-thirds majority, but it nonetheless overrode more presidential vetoes than for any president since Andrew Jackson. [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* Space launches for October included:
-- 03 OCT 20 / CYGNUS 14 (NG 14) -- An Orbital Sciences Antares booster was launched from Wallops Island off the coast of Virginia at 0116 UTC (previous day local time + 4) to put the 14th operational "Cygnus" supply capsule, designated "NG 14", into space on an International Space Station (ISS) support mission. It docked with the ISS Unity module two days later.
The cargo included a new toilet, and a set of CubeSats for the "Educational Launch of Nanosatellites (ELaNa) 31" mission, including:
The smallsats were deployed from the ISS later. The booster was in the Antares 230 configuration, with two RD-181 first stage engines and a Castor 30XL second stage.
-- 06 OCT 20 / STARLINK 12 -- A SpaceX Falcon 9 booster was launched from Cape Canaveral at 1129 UTC (local time + 4) to put 60 SpaceX "Starlink" low-Earth-orbit broadband comsats into orbit. The satellites were built by SpaceX, each having a launch mass of about 225 kilograms (500 pounds). This was the 13th Starlink batch launch. The Falcon 9 first stage soft-landed on the SpaceX drone barge; it was its third flight.
-- 11 OCT 20 / GAOFEN 13 -- A Long March 3B booster was launched from Xichang at 1657 UTC (next day local time - 8) to put the "Gaofen 13" geostationary Earth observation satellite into orbit. Although not many details were released, Gaofen 13 appears to be a follow-on to the Gaofen 4 satellite, launched in 2015. Gaofen 4 had a launch mass of about 4,600 kilograms (10,140 pounds), and had a visible imager with a resolution of 50 meters (164) feet, plus an infra-red imager with coarser resolution. Gaofen 13, like Gaofen 4, was placed in a geostationary slot that allowed it to overlook the Asia-Pacific region. Although announced as a civil Earth resource observation satellite, the geostationary Gaofens are suspected to be a military surveillance platform, to locate US carrier groups.
-- 14 OCT 20 / SOYUZ ISS 63S (ISS) -- A Soyuz booster was launched from Baikonur at 0545 UTC (next day local time + 6) to put the "Soyuz ISS 63S" AKA "MS-17" crewed space capsule into orbit on an International Space Station (ISS) support mission. The crew included Russian cosmonauts Sergey Nikolayvich Ryzhikov (2nd space flight) and Sergey Vladimirvich Kud-Sverchkov (1st space flight), and American astronaut Dr. Kathleen Hallisey Rubins (2nd space flight). The capsule docked with the ISS Rassvet module about 3 hours after launch, on a fast ascent trajectory.
-- 18 OCT 20 / STARLINK 13 -- A SpaceX Falcon 9 booster was launched from Cape Canaveral at 1225 UTC (local time + 4) to put 60 SpaceX "Starlink" low-Earth-orbit broadband comsats into orbit. The satellites were built by SpaceX, each having a launch mass of about 225 kilograms (500 pounds). This was the 14th Starlink batch launch. The Falcon 9 first stage soft-landed on the SpaceX barge.
-- 24 OCT 20 / STARLINK 14 -- A SpaceX Falcon 9 booster was launched from Cape Canaveral at 1531 UTC (local time + 4) to put 60 SpaceX "Starlink" low-Earth-orbit broadband comsats into orbit. The satellites were built by SpaceX, each having a launch mass of about 225 kilograms (500 pounds). The Falcon 9 first stage soft-landed on the SpaceX recovery barge in the Atlantic. This was the 15th Starlink batch launch.
-- 14 OCT 20 / GLONASS K (COSMOS 2547) -- A Soyuz 2.1b booster was launched from Plesetsk at 1908 UTC (local time - 4) to put a GLONASS K navigation satellite into orbit. It was assigned the series designation of "Cosmos 2547".
-- 26 OCT 20 / YAOGAN 30 -- A Long March 2C booster was launched from Xichang at 1519 UTC (next day local time - 8) to put the secret "Yaogan 30" payload into orbit. It was a triplet of satellites and may have been a "flying triangle" naval signals intelligence payload. The launch also included the "Tianqi 6" from Beijing-based company Guodian Gaoke, intended to provide commercial data relay services.
-- 28 OCT 20 / CESAT 2B, SUPERDOVES x 9: -- A Rocket Labs Electron light booster was launched from New Zealand's North Island at ---- UTC (local time - 11) to put the "CESAT 2B" Earth-imaging microsatellite into orbit for Canon Electronics. CE-SAT-IIB was a second-generation demonstrator satellite developed to test the company's imaging equipment in space. It carried a low-light / telephoto camera with dual lenses, plus a wide-angle camera.
The launch also included nine SuperDove Earth-imaging CubeSats for Planet as the "Flock 4e'" batch. Flock 4e' was a replacement for the "Flock 4e" satellites lost on a failed Electron mission earlier in 2020; that flight also lost an earlier-model Canon satellite. This was the 15th launch of the Electron; the flight was nicknamed "In Focus", as a nod to the Earth-observation payloads.
* As discussed in an article from NUATLAS.com ("NASA And ESA Finalize Agreement To Build Gateway Deep Space Outpost" by David Szondy, 27 October 2020), the space agencies of the US and Europe have now entered into a partnership agreement for building the Artemis Gateway deep space outpost.
The US is working to obtain international partners in the Gateway project. Scheduled to begin construction in cislunar orbit in 2024, the Gateway outpost is to be a staging point for missions to the lunar surface and deep space, -- ultimately, for the first crewed missions to Mars. One-sixth the size of the International Space Station (ISS), the Gateway will be assembled as modules launched into a halo orbit around the Earth-Moon Lagrange point, where the gravitational fields of the Earth and Moon balance out.
After it becomes operational, the Gateway will be crewed by astronauts arriving in the Orion spacecraft. Onboard Gateway, the crew will be able to remotely control lunar rovers, or embark on landers to descend to the Moon's surface.
Under the new agreement, ESA will provide habitation and refueling modules, as well as communications systems. ESA will handle operations of its modules; in addition, ESA is building two more "European Service Modules (ESMs)" for the Orion spacecraft that will provide propulsion, power, air, and water systems for the crew capsule.
Gateway will be open for use by both international partners and private companies wishing to launch lunar missions. It will also be used to test technologies for crewed Mars missions and to demonstrate the remote management and long-term reliability of autonomous systems.
COMMENT ON ARTICLE* ADVANCES IN 3D PRINTING (3): 3D printing isn't restricted to fabricating large structures from concrete: Amsterdam firm MX3D has printed a bridge from stainless steel. First displayed publicly in 2018, the bridge is now being tested and having sensors installed ahead of a planned installation over an Amsterdam canal.
California start-up firm Relativity Space in Los Angeles is getting ready to fly a nearly fully 3D-printed rocket, capable of placing 1,250 kilograms (2,755 pounds) into low Earth orbit. Tim Ellis -- Relativity Space's chief executive -- says that printed metal doesn't always have the same heat-dissipating performance as non-printed metal, but the printing process can add cooling channels that would be difficult to incorporate in a rocket engine with traditional fabrication methods. Since rockets are only used once, or possibly a few times, their components don't have to be as robust as those of aircraft.
Such large-scale metal-printed projects are built with robot arms that feed a thin metal wire to a laser that welds the material into place. Other familiar ways to print metal use a laser or a beam of electrons to melt or fuse a bed of powder into layers of finished product. Another approach binds a bed of powder with liquid glue, then sinters the structure in a furnace. Printers have also been designed in the past few years that extrude molten metals through nozzles, in much the same way as plastic parts are printed.
Aviation firms such as Boeing, Rolls-Royce, and Pratt & Whitney are using 3D printing to make metal parts, primarily for jet engines. It can be cheaper and less wasteful than milling metal blocks, and the intricate components often weigh less than their conventionally-made counterparts. Unfortunately, 3D-printed metals are prone to defects that can weaken the final products. LLNL's Chris Spadaccini and others are trying to use arrays of sensors and high-speed cameras to watch for irregularities such as hotspots of heat or strain, and then make adjustments in real time.
Many researchers are also hoping to improve the intrinsic strength of printed metals, in some cases by controlling the microstructures of the materials. For example, in 2017 a US team reported that the intense heat and rapid cooling used in 3D-printing stainless steel could alter the metal's microstructure in such a way that the product is stronger than those cast conventionally. More recently, researchers in Australia and the USA reported a titanium–copper alloy with similar strength advantages. Earlier 3D-printed titanium alloys tended, as they solidified, to form grains that grew in column-like structures. The copper helps speed up the solidification process, which results in grains that are smaller and sprout in all directions, strengthening the overall structure.
Mark Easton -- a materials engineer at RMIT University in Melbourne, and one of the leaders of the alloy work -- has already had conversations with aerospace companies interested in exploring uses for the material. He says it could also be used in medical implants such as joint replacements.
Many of the printing techniques that work for metals can also be used with ceramics, with potential applications that include fabricating dental crowns or orthopedic implants. Moulds for these objects are already made by 3D printing, with the material cast in the conventional way; 3D-printing the entire object could save time and expense, and even be done at a dentist's office.
However, Eduardo Saiz -- a materials scientist and ceramicist at Imperial College London -- says it is harder to control the microstructure of 3D-printed ceramics. Nearly all practical ceramic printing techniques also involve extensive post-print sintering that can warp or deform the part. Saiz believes ceramics have some catching-up to do: "In my opinion, ceramics is way behind polymers and metals in terms of practical applications." [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* COVID-19 VERSUS 1918 FLU: As discussed by an article from NEWATLAS.com ("NYC Study concludes COVID-19 Is As Deadly As The 1918 Spanish Flu" by Rich Haridy, 13 August 2020), the 1918:1919 flu pandemic -- sometimes called the "Spanish flu", though the first cases arose in the USA -- infected about a third of the human population on Earth and killed tens of millions, including 625,000 Americans. How does the current COVID-19 pandemic compare?
A new study has attempted to answer that question. It's not an easy task; virulence and lethality are population concepts, only meaningful with large numbers of people, consideration of circumstances, and the reporting of relevant data. In addition, medical science has advanced a lot since 1918, meaning more survive who wouldn't have in absence of the better medtech.
The study, led by Jeremy Faust from Brigham & Women's Hospital, took the approach of comparing "excess deaths" -- that is, deaths above the historical average -- in New York City in the first two months of COVID-19, against the same datapoint from NYC in the worst two months of that pandemic. The analysis concluded there were 287 deaths per 100,000 people in NYC at the peak of the 1918 flu pandemic. In comparison, the city saw 202 deaths per 100,000 during the COVID-19 peak in March and April 2020.
That might suggest COVID-19 isn't quite as bad -- but again, the comparison is not on level ground. According to the study:
BEGIN QUOTE:
... because baseline mortality rates from 2017 to 2019 were less than half that observed from 1914 to 1917 (owing to improvements in hygiene and modern achievements in medicine, public health, and safety), the relative increase during the early COVID-19 period was substantially greater than during the peak of the 1918 H1N1 influenza pandemic.
END QUOTE
In other words, the excess deaths caused by COVID-19 were higher in proportion to the lower, as compared to 1918, rate of normal deaths. Faust suggests that COVID-19 is at least as dangerous as the 1918 flu:
BEGIN QUOTE:
They're comparable events in terms of magnitude. I think maybe we imagine pandemics and plagues and other calamities to be this sort of historical events where the streets are lined with dead bodies and there's pestilence and filth, but what our numbers show is that what happened in New York was pretty similar to what happened in the greatest modern pandemic.
END QUOTE
Eric Topol, from the Scripps Research Translational Institute, has pointed out that, given the improvements in medical technology over a century, it is disconcerting that COVID-19 is yielding similar death rates to the 1918 flu:
BEGIN QUOTE:
There was no such thing as an intensive care unit, there was no ventilator, there was nothing. I mean, they basically had masks and distancing. We have so much more, and yet the mortality is roughly comparable.
END QUOTE
There's been a strong tendency, unfortunately boosted by politics, to minimize the threat of COVID-19, to adopt a "just ignore it" policy. In their study, Faust and his colleague say they want people to grasp the "unusual magnitude of the COVID-19 pandemic." COVID-19 cannot be ignored, and we can't deal with it unless we face the threat directly.
* A related article from TIME.com ("The 1918 Flu Pandemic Killed Hundreds of Thousands of Americans. The White House Never Said a Word About It" by Melissa August, 11 August 2020) discussed the Federal government's response to the 1918:1919 flu pandemic -- which was to ignore it, as it killed an estimated 675,000 Americans.
That was partially due to the standards of the time, in which public health systems were in a primitive state of development, the issue being regarded as the responsibility of the states and localities. As far as the Federal government went, the war effort came first. Troops were packed onto ships to be sent to France, with flu cutting through their ranks; tens of thousands died. One of the strange features of the 1918 flu was that it seemed to come down harder on the young and healthy, instead of the old. That may have been because a similar strain had been encountered by older people some decades in the past, and so they had greater resistance.
In any case, even White House staff fell ill. When Wilson went to Paris to negotiate the Treaty of Versailles after the World War I armistice, A young American aide in the peace delegation, 25-year-old Donald Frary, took sick with the flu and died. Wilson became ill as well, but it's not clear if it was from the pandemic flu or a different strain. The USA has not seen its last pandemic; hopefully, the next time will be better handled than the previous two.
COMMENT ON ARTICLE* THE COVID-19 MENACE (19): As discussed by an article from SCIENCEMAG.org ("This Cow's Antibodies Could Be The Newest Weapon Against COVID-19" by Mitch Leslie, 5 June 2020) SAb Biotherapeutics of Sioux Falls, South Dakota, has devised an unorthodox way to produce antibodies against SARS-CoV-2: they use genetically-modified cows.
To manufacture antibodies for treating or preventing diseases, companies usually turn to sources like cultured cells or tobacco plants. However, two decades ago, researchers began to work on using animals to produce antibodies. Eddie Sullivan, SaB Biotherapeutic's president and CEO, says that cows make good antibody factories; it's not just because they have more blood than smaller animals genetically modified to synthesize human versions of the proteins -- but their blood can also contain twice as many antibodies per milliliter as human blood.
It is also not much more difficult to get them to produce a diverse set of "polyclonal" antibodies, that hit the virus from different angles, than it is to get them to produce "monoclonal" antibodies that are all the same. Polyclonal antibodies tend to be more effective than monoclonal antibodies, and viral mutations don't neutralize their effect as easily.
When the COVID-19 pandemic hit, SAb Biotherapeutics had already finished a clinical trial with cow-generated antibodies against the MERS coronavirus. Sullivan says that effort "gave us the initial knowledge to focus on the right target." Within 7 weeks, the cows were generating antibodies against SARS-CoV-2's spike.
The cows were genetically modified, starting out as skin cells from cows. The cow genes to produce cow antibodies were "knocked out" and replaced with human antibody genes. The resulting chimera DNA was inserted into a cow egg cell, which was then implanted in a cow. Over the past two decades, the company has produced several hundred cows with human immune systems.
To get the cows to generate antibodies, they are first given a "starter immunization", using a DNA vaccine that incorporates a component of the viral genome to prep a cow's immune system. Next, the cows are given an injection that contains a piece of SARS-CoV-2's spike protein, with the cows then churning out antibodies. In a month, one cow can yield enough antibodies to treat several hundred patients.
In test-tube studies, the polyclonal cow antibodies proved four times more effective than convalescent plasma in preventing the virus from entering cells. Sullivan says clinical trials are to follow, to determine if the antibodies can prevent people from getting sick, and if they are effective in treating people who already are sick.
There is some skepticism that cows are the best method for producing antibodies -- and in fact, so far, no antibodies generated by the animals have been approved for treating any disease. However, infectious disease specialist
Jeffrey Henderson -- of Washington University School of Medicine in Saint Louis sees the cow-produced antibodies as a "logical next step" to the convalescent plasma he has been studying, saying: "The whole approach is based on sound science and on past experience going back more than a century."
ED: This is a very interesting idea -- but in response to articles on the subject linked to from Twitter, the reader commentaries tended towards the hysterical, for example claiming the cows would soon generate diseases dangerous to humans. That is not impossible, but the obvious ignorance of the commentaries suggested they shouldn't be taken too seriously. [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* AMERICA'S CONSTITUTION (125): Gerald Ford won election in 1948, to become the Representative in the House from Michigan's 5th congressional district; he would remain in that role for 25 years, the last nine of them as House Minority Leader. Ford described himself as "a moderate in domestic affairs, an internationalist in foreign affairs, and a conservative in fiscal policy." He was low-key, a NEW YORK TIMES editorial saying that "saw himself as a negotiator and a reconciler, and the record shows it: he did not write a single piece of major legislation in his entire career."
Nonetheless, he was highly respected, a "Congressman's Congressman", and served ably in House committees, particularly the Defense Committee. His voting record demonstrated a steady commitment to NATO and civil rights. Suggestions were made to Ford that he run for the US Senate or for the governor's office in Michigan, but he wasn't interested, his goal being to become the House Speaker, calling that the "ultimate achievement":
BEGIN QUOTE:
To sit up there and be the head honchou of 434 other people and have the responsibility, aside from the achievement, of trying to run the greatest legislative body in the history of mankind ... I think I got that ambition within a year or two after I was in the House of Representatives.
END QUOTE
One of Ford's most noteworthy achievements as a Member of the House was, as mentioned earlier, to become a prime mover in the Warren Commission, investigating the assassination of JFK. He was chosen by LBJ for the commission because Johnson wanted the White House to be in charge of the investigation, and sidetrack Republicans in Congress from starting their own investigations. That meant enlisting highly-respected Republicans like Ford to the commission, so that it couldn't be accused of being a cover-up. It was long accused of being a cover-up, but never with any good reason.
Certainly, Ford was no obedient tool of LBJ. As concerns about the progress of the war in Vietnam grew in 1966, Ford and Congressional Republicans began to push on the Johnson Administration, claiming that the USA wasn't doing enough to win the war. Ford said as much in a speech in the House, with LBJ replying that Ford had played "too much football without a helmet".
Public unease over the war led to Republican gains in the 1966 midterms -- not enough to take over the House, but enough to increase pressure on LBJ. Ford, working with Illinois Senator Everett Dirksen, conducted a series of TV press conferences, what became known as the "Ev & Gerry Show". LBJ was thin-skinned about criticism, saying: "Gerry Ford is so dumb he can't fart and chew gum at the same time." -- which was reported in a sanitized form in the media.
With the election of Richard Nixon, Ford shifted his efforts as House Minority Leader to pushing the White House agenda, proving able in getting bipartisan support for important measures. Nonetheless, he chafed at being Minority Leader instead of Speaker, and contemplated retiring from politics no later than 1976. Then, suddenly, the resignation of Spiro Agnew catapulted Ford to the vice-presidency, the appointment being resoundingly approved by Congress. With the resignation of Nixon on 9 August 1974, Ford became the 38th POTUS. He was the only person to become POTUS without having been elected vice-president or president.
On 20 August, Ford nominated former New York Governor Nelson Rockefeller to become the new vice-president. Some conservative Republicans were not happy with the choice, but Rockefeller was confirmed anyway. More controversially, as mentioned earlier, on 8 September 1974, Ford issued Proclamation 4311, granting Richard Nixon a full pardon for any crimes he might have committed against the United States while president. Although there was some valid rationale behind the pardon, it reeked of a deal, with THE NEW YORK TIMES saying that it was a "profoundly unwise, divisive and unjust act" that destroyed the new president's "credibility as a man of judgment, candor and competence". [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* GIMMICKS & GADGETS: As discussed by an article from SCIENCEMAG.org ("Rivers Could Generate Thousands Of Nuclear Power Plants Worth Of Energy, Thanks To A New 'Blue' Membrane" by Robert S. Service), the idea of extracting electricity from the flow of rivers into the ocean -- discussed here in 2019 -- is picking up steam.
The "blue energy", as it's called, involves spanning a membrane between the river's outlet and the sea. Ions from sea salt migrate through the membrane, generating electricity. It's much like a giant flow battery. It promised to generate a lot of electricity, since rivers dump about 37,000 cubic kilometers of freshwater into the oceans every year. Some estimates suggest blue energy could provide about 2.6 terawatts of power in all, or the equivalent of about 2,000 nuclear power plants.
French researchers devised the first blue-energy membrane in 2013, using a ceramic film of silicon nitride -- commonly used in industry for electronics, cutting tools, and ETC -- pierced by a single pore lined with a boron nitride nanotube (BNNT). Since BNNTs are highly negatively charged, the French team suspected they would prevent negatively charged ions in water from passing through the membrane.
Indeed, they found that when a membrane with a single BNNT was placed between fresh water and salt water, the positive ions passed through to the fresh water, while the negative ions were blocked. The charge imbalance was so great that the researchers estimated a single square meter of the membrane -- with millions of pores per square centimeter -- could generate about 30 megawatt-hours per year, enough to power more than 400 homes.
Unfortunately, this was no more than a proof of concept, since the scheme, as originally devised, couldn't be reasonably scaled up. Now a team under Jerry Wei-Jen Shan -- a mechanical engineer at Rutgers University in Piscataway, New Jersey -- has figured out how to do so. The BNNTs were easily obtained from a company. The researchers then added the nanotubes to a polymer precursor that's laid out as a 6.5-micrometer-thick film.
The problem was orienting the nanotubes. The researchers thought of using a magnetic field, but the BNNT aren't magnetic. No problem, they just painted the tubes with a positively-charged coating -- based on molecules too big to fit inside the tubes, leaving them open -- and then added negatively-charge magnetic iron oxide particles to the mix, which affixed to the positively charged coating molecules. That done, they used a magnetic field to align the BNNTs, then cured the polymer using ultraviolet light. As a final step, the researchers used a plasma beam to trim down both sides of the film, ensuring that the nanotubes were open.
The end product contained some 10 million BNNTs per cubic centimeter. When the research team placed their membrane in a small vessel separating salt- and freshwater, it produced 8,000 times more power per area than the previous French team's BNNT experiment. Shan believes that's because his BNNTs are narrower than those of the French experiment, and were better at excluding negatively charged chloride ions. In addition, only 2% of the BNNTs in the film were open on both sides; Shan is confident his team can easily improve on that number.
* Technological advances are sometimes demonstrated by major improvements in mundane technologies, instead of whizzy gadgetry. As a case in point, a press release from the US Air Force Research Lab (AFRL) described a new winch cable for the C-17 cargolift aircraft.
The current winch cable is made of steel; one of its problems is that if it breaks under tension, it can whipsaw around and cause considerable damage. The new cable is made of synthetic materials, and it seems doesn't stretch much: if it breaks, it simply falls in place.
The new cable was developed by the AFRL, working with the Samson Rope Company. It is 85.4 meters (280 feet) long; it only weighs 8.35 kilograms (14 pounds), compared to the old cable's 36.3 kilograms (80 pounds). The lighter weight translates into more payload for the C-17, and also makes the cable much easier to handle. Last but not least, the new cable is 40% cheaper.
* An article from ABC.com dated 14 November 2019 warned travelers to "Beware Of Juice Jacking". Wot? The warning was about using USB chargers in airports to recharge a phone, since sometimes devious Black Hats infect the chargers with malware, to infect phones plugged into the charger.
A little further investigation suggests this is not such a problem, at least for more recent phones. These days, if a phone is plugged into an unfamiliar USB socket and something tries to get into the phone via USB, the phone asks the user to grant permission. If juice jacking is still a problem, it won't be for much longer.
COMMENT ON ARTICLE* ADVANCES IN 3D PRINTING (2): New 3D printing technologies often have immediate commercial potential. Some researchers start forming companies before they publish their advances. Even as Joseph DeSimone was publicly revealing his new 3D printer technology, he officially launched a startup firm -- Carbon 3D in Redwood City, California -- though he had registered the company two years earlier. Funding has been pouring in; Carbon 3D has high-profile contracts with Adidas to make rubber-like midsoles for athletic shoes, and with sports-gear firm Riddell to manufacture customized helmet padding for American-football players.
Northwestern's Chad Mirkin, along with his colleagues James Hedrick and David Walker, have similarly launched a start-up, Azul 3D in Evanston, Illinois, to commercialize their technology, which they call "High-Area Rapid Printing (HARP)". In addition, Monash's Timothy Scott and Ann Arbor's Mark Burns are working on a commercial prototype printer with their Ann Arbor-based start-up Diplodocal, a name derived from the Greek for 'double beam'.
New resin-printing techniques are still emerging. One scheme starts with a small spinning glass holding liquid resin; as the glass spins, a projector shines a loop of video onto it that shines 2D slices of the desired object into it. Within seconds, the final object solidifies inside the liquid resin -- no layers needed. The approach was inspired by X-ray and computed-tomography scans, which image cross-sections of a solid object to determine a 3D structure. This is the reverse: back-projecting cross-sections to form a 3D object.
This research has attracted a lot of attention, Harvard's Jennifer Lewis saying it has a major "gee-whiz factor". It has significant limitations: the resin used must be transparent, and the printed object must be small enough for light to pass through it to cure it. However, it also has a potential advantage: it can handle highly viscous resins, which other resin-based printers struggle to suck through the narrow dead zone. That means it could make stronger materials and more accurate prints.
Industry has been very interested, according to Christopher Spadaccini -- a materials and manufacturing engineer at Lawrence Livermore National Laboratory (LLNL) in California. Spadaccini was a member of the team that published the idea in early 2019, although a group at the Swiss Federal Institute of Technology in Lausanne (EPFL) independently developed the same concept and reported it earlier. Spadaccini thinks the technology has tremendous commercial potential because it has modest hardware requirements, saying: "In the end, really, what you need is a halfway-decent projector and a rotating stage."
* While chemists work on smarter ways to 3D-print intricate designs, engineers are pushing the limits in the 3D printing of concrete, using computers and robots to precisely automate the pouring process. The world's first 3D-printed concrete pedestrian bridge was made by researchers at the Institute for Advanced Architecture of Catalonia in Barcelona, Spain, and installed in a park in Alcobendas, near Madrid, in 2016. Twelve meters (40 feet) long, the bridge features a lattice structure designed with algorithms that maximize strength and minimize the amount of material needed.
Other teams have made similar structures, including a 26-meter (85-foot) long bridge in Shanghai, China, produced by engineers at Tsinghua University in Beijing -- while teams and companies in China and the Netherlands have 3D printed demonstration houses. Those structures aren't constructed in one print job, however: separate segments are printed , then connected. By producing bridges and houses more cheaply and efficiently, 3D printing could reduce concrete's carbon footprint. [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* ASSESSING BLACK HOLES: As discussed by an article from SCIENCEMAG.org ("The Universe Teems With Weird Black Holes, Gravitational-Wave Hunters Find" By Adrian Cho, 28 October 2020), in 2015, after years of searching, earthbound observatories finally observed gravitational waves, the product of the collision of two black holes billions of light-years away. Other events quickly followed, and now researchers have published a statistical study of all the events they have observed -- 50 in all. The study suggests that black holes are more common and stranger than expected, and provides clues on exactly how the collisions occur.
The observations came from three L-shaped optical interferometer facilities that can measure the slightest distortion of space, caused by passing gravitational waves. Two of those facilities belong to the "Laser Interferometer Gravitational-Wave Observatory (LIGO)" in the USA, with sites in Louisiana and Washington; they have arms 4 kilometers (2.5 miles) long, and were the first to spot a gravitational wave. The third facility is "Virgo", near Pisa in Italy; it has arms 3 kilometers (1.85 miles) long, and joined the hunt in 2017.
Most of the 50 events detected were mergers of black holes, but the observations include two possible neutron-star mergers and one possible neutron star / black hole merger. Frank Ohme -- a gravitational wave astronomer at the Max Planck Institute for Gravitational Physics -- says that the study shows that for black holes, "the diversity is surprisingly large."
The signals from the mergers are in the form of messy chirps, which can reveal specifics of the event -- notably the masses of the black holes involved. They expected to find a "mass gap" between about 45 and 135 solar masses, in accordance with theoretical considerations that say stars within a certain mass range will blow apart before they can collapse into black holes.
However, LIGO and Virgo have now spotted mergers involving black holes right within the gap, including one with a mass of roughly 85 solar masses. This is puzzling, because the theory seems well-founded; there appears to be some other factor involved. Similarly, scientists expected another "forbidden" range below 5 solar masses, based on previous observations of individual black holes peacefully orbiting normal stars -- but at least one hole in the catalog appears to fall below that limit.
The census of black holes has also led researchers to examine whether black holes in a merging pair point in the same direction as they orbit each other -- which may be a clue as to how the pair came together in the first place. If the spins align with the orbital axis, the black holes might have formed from a pair of stars that were born together, naturally acquired matching spins, and remained companions after they collapsed. If the spins point in different directions, the black holes might have formed first and then paired in some way later.
In particular, if one of the black holes spins in the opposite sense of the orbit, the pair would more likely come from the mingling of black holes that had already formed. It's hard very hard to tell for sure if that's happening from a single signal, having a good set of events have allowed researchers to conclude that at least some of the mergers involved reversed spins. That suggests that black-hole pairs form in a number of ways.
Researcher have even been able to consider how the number of black hole mergers may have changed over cosmic time. The rate is expected to be higher in the early Universe, when the pace of star formation was also higher -- but earlier data suggested that rate might be up to 100,000 times higher than it is currently. The study suggests that the rate of mergers 8 billion years ago was no more than 10 times what it is now.
LIGO and Virgo are continuing observations, and being improved; the new catalog of events is only a start. Further observations will provide more details -- for example, correlations between spin alignment and the masses of black holes might give hints that the heaviest black holes involved were products of earlier mergers. Says one astrophysicist: "We've answered a lot of questions we didn't even know we had, but we raised even more. This is just the beginning of the science."
COMMENT ON ARTICLE* THE COVID-19 MENACE (18): AstraZeneca -- the fourth team being funded by DARPA to work on MABs against SARS-CoV-2 -- is screening through blood from recovered patients and spike-injected mice to find antibodies; the company is also sifting through a huge library of effectively random antibodies, generated using bacteriophages that infect bacteria to churn out those antibodies. Mene Pangalos -- AstraZeneca's executive vice president of pharmaceutical R&D -- says the objective is to make a cocktail, "and it may end up being a cocktail that includes other companies' antibodies."
Research groups are also hunting for clues from coronavirus diseases such as SARS and MERS. Vir Biotechnology, for example, has found an antibody in a recovered SARS survivor from 2003 that neutralizes SARS-CoV-2 -- researchers reporting that antibody binds to a region of the RBD that is "highly conserved" between the two coronaviruses, suggesting the region doesn't mutate much. The company went on to modify the antibody to make it more potent, giving a longer life and enhancing its immune system stimulation.
Jacob Glanville -- an immunologist and computer scientist who runs Distributed Bio -- designed neuts for SARS-CoV-2 using a computer, drawing on genetic sequences and structures of ones known to thwart the SARS virus in cells and even mice. With molecular modeling software, Glanville mutated the antibodies to the SARS virus into billions of variants. His team then used phages to generate a still larger library of antibodies that might work, to then sift through "this vast mutational space", and select 50 candidates. They are now conducting in vitro tests, to narrow the candidates down to 13 for more thorough evaluation.
Glanville is ambitious, seeking to find antibodies that can effectively neutralize a wide range of coronaviruses, so when a new strain emerges, there's no need to come up with a new vaccine. He says: "We don't have to play this game every time."
The diversity of work on MABs against SARS-CoV-2 is encouraging, but it inevitably means some confusion. La Jolla's Eric Saphire asks: "How do you know what is really best and why?" She heads the Coronavirus Immunotherapy Consortium, funded by $1.7 million USD from the Bill & Melinda Gates Foundation; the consortium is now setting up a large-scale, blinded evaluation of candidate monoclonals in test tube studies to estimate their ability to thwart SARS-CoV-2 infection of human cells. That is to lead to comparative evaluation in animal models, but more funding is needed for that step.
A doctor in northern Italy who recovered from COVID-19 and has, like Dr. X, contributed his own plasma to AstraZeneca's antibody hunt, emphasizes that it is not guaranteed that MABs will work against SARS-CoV-2. The doctor -- who remains anonymous because of his hospital's concerns about publicity -- says: "We don't know the role of neutralizing antibodies in this disease," says the doctor, who asked not to be named because of his hospital's concerns about publicity.
Over the long run, an effective COVID-19 vaccine would eliminate the pressing need for SARS-CoV-2 monoclonal antibodies. AstraZeneca's Pangalos says that a vaccine would be "fantastic," he says, adding that AstraZeneca didn't start this project for strictly business reasons. The first priority is to stop COVID-19 by any useful means: "It's important for one of us to solve this pandemic so that we can all get back to some semblance of normality." [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* AMERICA'S CONSTITUTION (124): Gerald Ford had actually been born as Leslie Lynch King JR, in Omaha NE in 1913. It appears his father was an abusive husband, and so his mother, Dorothy Ayer Gardner, left and divorced him, obtaining full custody of the infant, and eventually settling in Grand Rapids MI. In 1917, she married Gerald Rudolff Ford, a salesman, with the child becoming known as "Gerald JR", though he didn't formally change his name until 1935. Dorothy had three more children, all boys, with Gerald SR, who was by all accounts a good father to his children.
Gerald Ford JR was by all accounts an all-American boy, being an enthusiastic Boy Scout -- he became an Eagle Scout, the only one to become president -- and outstanding athlete; he was captain of the Grand Rapids South High School football team, and was a star player of the University of Michigan Wolverines. As president, Ford liked to have the Navy band play "The Victors", the Wolverine fight song, instead of the traditional "Hail To The Chief" at state events.
Ford graduated from Michigan in 1935 with a BA in economics. He turned down offers to go pro football -- he loved football, but he had other ambitions -- to take a job at Yale as an assistant coach, and applied to Yale Law School. Yale officials were stuffy about admitting him since he was a full-time coach at the school, but he was finally admitted in 1938.
While in law school, Ford became a student activist, working to keep America out of Europe's looming war, with links to the isolationist America First movement. He graduated high in his class in 1941, to be admitted to the Michigan bar, and then setting up he opened a Grand Rapids law practice with a friend, Philip Buchen.
Isolationism came to an abrupt halt on 7 December 1941, with Japan's attack on Pearl Harbor. Ford, a patriot, soon enlisted in the US Navy, starting out as an ensign, working as an instructor at the Navy Preflight School in Chapel Hill, North Carolina. He also worked as a coach, sports being a very significant component of military life at the time.
In the spring of 1943 Ford, by then a Navy lieutenant, applied for sea duty, to be assigned to the light carrier USS MONTEREY, with the ship seeing action in Pacific campaigns up to late 1944. The carrier was never damaged in action, but it was a victim of Typhoon Cobra that hit Admiral Halsey's Third Fleet on 18:19 December 1944. 800 men were lost, with three destroyers sent to the bottom; aircraft in the MONTEREY's hangar deck were torn loose from their tie-downs and started a fire. Lieutenant Ford was officer of the deck at the moment; he assessed the situation and reported it to the captain, with damage crews scrambling to suppress the fire under difficult sea conditions. The fire was contained, but the ship needed a complete overhaul.
Ford more or less reverted to his original Navy role, going to the Navy Pre-Flight School at Saint Mary's College of California, where he became a coach. He only stayed there a few months, joining the staff of the Naval Reserve Training Command at Naval Air Station Glenview in Illinois. He mustered out in early 1946 with the rank of lieutenant commander, with a number of military decorations to his credit. He went back to Grand Rapids and his law practice, to also become more active in politics. The war had ended his isolationism, Ford saying that he became a "converted internationalist".
Ford married Elizabeth "Betty" Bloomer in 1948; she'd been married before, but they would remain married to the end. She had actually been a fashion model and worked as a performer in a dance company for a time. The wedding was postponed until after Ford stood election, since voters might have been turned off by his marrying a divorced ex-dancer. They had four kids in the 1950s: Michael, John, Steven, and Susan. [TO BE CONTINUED]
START | PREV | NEXT | COMMENT ON ARTICLE* SCIENCE NOTES: As discussed by an article from SCIENCEMAG.org ("New Genetic Tools Promise To Unlock Secrets Of Microscopic Marine Life" by Elizabeth Pennisi, 6 April 2020), half of the oxygen we breathe comes from ocean microbes -- but we know very little about them. Now an international collaboration of researchers have devised a way to unlock the genomes of a handful of these organisms by genetically engineering their DNA.
Plankton are microscopic organisms that color our oceans blue, green, and sometimes even red. Some of these plankton are single-celled organisms called "protists" that, like plants, use light to transform carbon dioxide into oxygen, and they also make up the base of the ocean's food chain.
In 2015, the Gordon and Betty Moore Foundation -- a philanthropic organization that supports basic research about microbes and the environment -- gave $8 million USD to researchers to map out the world of marine microorganisms. Studies of animals, plants, yeast, and bacteria have shown that when scientists alter an organism's genes, they find clues to how those genes, and of course the organisms themselves, actually work. The researchers involved eventually pooled efforts, selecting a range of 39 species to target. Some species were chosen because of their economic importance; protist-linked red tides and other algal blooms can be catastrophic to fisheries and recreation. Others were selected because they represent different branches of the protist family tree.
The teams collected creatures with names like "archaelastid", "opisthokont", and "coccolithophore", mostly from water in coastal environments. That done, the researchers had to "fishtank" the various species, growing enough of them to analyze. The researchers tinkered with various combinations of nutrients and temperatures with each to see what worked best.
The next step was to explore the genes of these microorganisms by inserting foreign genes into them -- which was new ground, there having been little work on genetically modifying protists before. They found out that sometimes shooting tiny gold or tungsten particles coated with DNA was highly effective at getting the DNA through the cell membrane. In other cases, the researchers zapped cell membranes with electricity to make them leaky, allowing DNA to filter in.
Of course, the new genes had to be integrated with the genomes of host organisms, or at least generate proteins on their own. Sometimes a gene simply started making proteins; sometimes the host's enzymes destroyed it. In other cases, the researchers discovered that enzymes typically used for genetic engineering didn't work at the low temperatures some of the protists live at, so they had to find new enzymes.
In total, they added genes to 13 species -- included a protist that kills fish with its toxins, and one that also infects mollusks and amphibians. Along with revealing more about the genetic workings of protists and their evolution, the effort was a first step towards knowing how to genetically modify them.
* As discussed by an article from SCIENCEMAG.org ("Astronomers Find Closest Black Hole To Earth" by Daniel Clery, 6 May 2020), our Milky Way Galaxy is believed to contain hundreds of millions of black holes. However, only a few dozen of them have been found, revealed by the x-ray glow of hot gases in the "accretion disk" that surround them. Now astronomers have found a "dark" black hole -- not marked by x-ray emission -- a mere thousand light-years from Earth, which places it in our galactic neighborhood.
How is it possible to spot a black hole that isn't generating observable radiation? Astronomer use a trick commonly used to find distant, unseen planets: by the subtle wobble in a star, revealed by shifts in its light spectrum, due to the gravitational influence of the planet or other object. The bigger the object, the bigger the wobble.
Thomas Rivinius, an astronomer with the European Southern Observatory (ESO), and his team studied the unusual star system HR 6819 in this way using a 2.2-meter telescope in Chile, operated by ESO and the Max Planck Society. They thought it was a binary system, with two stars, but the wobble was more complicated than would be the case if that were so. It turned out to be a triple system, with one star in a fast 40-day orbit with an unseen companion and another star on a more distant, slow-moving path. The invisible companion's mass was four times that of our Sun -- Rivinius saying that if it were a star, "we would have seen it".
Confirming that the object really is a black hole will require use of the ESO's high-resolution optical interferometry system. Rivinius says that: "We wouldn't see the black hole [but should see one of the stars] orbit something else that's not there."
Hunting down the nearby black hole was not a trivial task. According to astronomer Benjamin Giesers of the University of Goettingen: "You have to observe a lot of stars to find one." He and his team surveyed 25 globular clusters, balls of stars orbiting the center of the Milky Way that each contain hundreds of thousands of stars. In 2017, they found one black hole candidate, about 4.5 times the mass of the Sun, setting up a wobble on its companion star.
In 2019, Todd Thompson -- an astronomer at Ohio State University in Columbus -- and his team made a further discovery, after combing through data culled from the Sloan Digital Sky Survey and using the All-Sky Automated Survey for Supernovae to cut down the numbers. Thompson says: "We were looking for a star doing something that it shouldn't be doing." They finally found a rapidly rotating giant star designated 2MASS J05215658+4359220, which, from its wobbles, indicated a black hole companion of about 3.5 solar masses.
Thompson says the new find will be "well-studied" -- but adds a note of caution: "I don't think anything is ironclad. You have to be skeptical."
COMMENT ON ARTICLE* ADVANCES IN 3D PRINTING (1): 3D printing has often been discussed here in this blog, the last mention at length being in 2014. An article from NATURE.com ("3D Printing Gets Bigger, Faster, And Stronger" by Mark Zastrow, 5 February 2020), surveyed the current status of the technology.
There was a time, not long ago, when 3D printing was mostly focused on fabricating small, low-quality prototype parts. Now, not only is 3D printing becoming faster and producing larger products, but researchers are coming up with new ways to print and are creating stronger materials -- sometimes even including multiple materials in the same product. Sportswear firms, aviation and aerospace manufacturers, and medical-device companies are eager to exploit the technology. Jennifer Lewis -- a materials scientist at Harvard University in Cambridge, Massachusetts -- says: "You're not going to be sitting in your home, printing out exactly what you want to repair your car any time soon, but major manufacturing companies are really adopting this technology."
Researchers are pushing the limits of what 3D printing can do. Iain Todd -- a metallurgist at the University of Sheffield in the UK -- says: "We can get performance out of these materials that we didn't think we could get. That's what's really exciting to a materials scientist. This is getting people used to the new weird."
Traditional manufacturing often involves milling a shape out of a block; 3D printing instead prints out the shape, meaning less waste of material, and the ability to fabricate elaborate parts, such as intricate lattice structures, that are otherwise hard to fabricate
Low-cost hobbyist printers print by squeezing out thin plastic filaments from heated nozzles, building up a structure layer by layer -- a method known as "fused deposition modeling (FDM)". There are other approaches; one of the oldest uses an ultraviolet laser to scan across and solidify (or "cure") light-sensitive resin, layer by layer. This scheme was described as far back as 1984, in a patent filed by Charles Hull, the founder of a company named 3D Systems of Rock Hill, South Carolina.
The latest techniques still use light-sensitive resin, but are faster and larger-scale, following improvements reported in 2015 by a team led by Joseph DeSimone -- a chemist and materials scientist at the University of North Carolina at Chapel Hill. Early printers were slow, could only print small parts, and were prone to producing layered, imperfect and weak structures. The early printers found a niche in rapid prototyping, making plastic model parts as mock-ups for later production by conventional methods. Timothy Scott -- a polymer scientist at Monash University in Melbourne, Australia -- says early printers weren't much fun: "Basically making trinkets and knick-knacks. For a polymer chemist, it was pretty dull."
DeSimone changed the rules by introducing a way to print light-sensitive resin up to a hundred times faster than conventional printers. His scheme uses a stage submerged in a vat of resin. A digital projector shines a pre-programmed image up at the stage through a transparent window in the bottom of the vat, with the light curing an entire resin layer at once. The important trick was to make the window permeable to oxygen, with the oxygen forming a layer to prevent the resin from sticking to the window. Once a layer is printed, the stage moves up, resin flows in underneath, and a new layer is printed.
Jennifer Lewis says other labs were working on similar concepts at the time -- but adds that DeSimone's resins could undergo a second reaction in a post-print heat treatment to strengthen the finished product: "It opens up a much broader array of materials."
Chad Mirkin -- a chemist at Northwestern University in Evanston, Illinois -- has improved on DeSimone's scheme, using a layer of clear oil on the bottom of the vat, and not relying on oxygen to keep the resin from sticking to the window. The oil also acts as a coolant, bleeding off heat that can deform a printed part. Mirkin's printer can handle resins whose curing isn't inhibited by oxygen; he claims it also can print ten times faster than DeSimone's printer.
Taking another approach, Monash's Timothy Scott, working with Mark Burns at the University of Michigan in Ann Arbor, have devised a printer that obtains selective control of reactions by mixing into the resin a chemical that can be activated by a second lamp emitting a different wavelength of light. By varying the ratio of the strength of the two light sources, the researchers can control the thickness of the photo-inhibited zone -- allowing the production of more complicated patterns, such as surfaces embossed with seals or logos. [TO BE CONTINUED]
NEXT | COMMENT ON ARTICLE* ELITE CONTROLLERS: There are a few people who have been infected with the HIV pathogen, but it doesn't seem to bother them. Now, according to an article from SCIENCEMAG.org ("How Elite Controllers Tame HIV Without Drugs" by Jon Cohen, 26 August 2020), now an in-depth genomic analysis of these "elite controllers (EC)", who account for less than 0.5% of all HIV infections, gives a clue as to how they keep the virus under control -- which promises to help researchers defeat HIV.
All but one of the 64 ECs studied in this research have many HIV genomes -- "proviruses" -- integrated in their cells. It turns out that, compared with people who have to take anti-retroviral (ARV) drugs to keep HIV under control, elite controllers have far more proviruses in chromosome regions where little gene activity occurs. Somehow, the ECs have eliminated infected cells with proviruses parked in areas where they more easily co-opt the cellular machinery needed to copy themselves. As a result, even when the virus replicates, the EC immune system can suppress it.
The challenge now is to identify how to translate the EC trick to the much larger HIV-infected population, but Mathias Lichterfeld -- an infectious disease physician at Brigham and Women's Hospital and a co-author of the work -- says the research "gives us a blueprint."
When people on ARVs stop taking the drugs, HIV typically floods their blood within weeks, as "reservoirs" of proviruses hiding out in various cells and tissues go into action. As a result, HIV cure researchers have long tried to reduce the size of these reservoirs. However, the study -- led by immunologist Yu Xu of the Ragon Institute of MGH, MIT and Harvard -- suggests the size of a reservoir may be less important than limiting proviruses to quiescent chromosome homes.
HIV typically splices its provirus into a cell's genes, with the virus then taking over the gene transcription machinery needed to turn out new HIVs. It was then a surprise Yu's team pinpointed the location of nearly 4,000 proviruses in cells from the elite controllers and 42 people on ARVs to find that in ECs, 45% of the proviruses reside in "gene deserts" -- regions of chromosomes where little transcription occurs. In people on ARVs, the number was 17%.
Earlier studies on ECs were limited by small sample size, a necessary consequence of the rarity of ECs. 64 is not a great sample size, but it's a big improvement. One member of the cohort presents an extreme case: what amounts to a natural cure. The woman, Loreen Willenberg -- who was diagnosed as HIV positive in 1992 yet remains healthy without ARVs -- had the lowest levels of proviruses of anyone in the study. In addition, the only proviruses found among the billions of her cells studied were genetically broken, incapable of producing new HIVs. Yu says: "We did not do integration site analysis on [her] samples, because there's no intact provirus -- and even the defective proviruses were so rare in her genome."
Willenberg has had her blood levels of HIV monitored for 24 years and has only had one detectable burst of viral replication, when she had a bad bout of the flu. Intensively studied by many HIV scientists, almost 15 years ago, Willenberg established a foundation that helps elite controllers -- some of whom joined this clinical study. She says: "If there were some way that this unique state of natural control of HIV infection could be somehow understood and then translated to individuals who did not spontaneously control HIV infection, then that's what I had to do."
Previous studies of Willenberg and other ECs suggest they often have a genetic predisposition to mount stronger immune responses against the virus. Yu and her team suspect this response selectively targeted cells with the most fit proviruses, skewing controllers' reservoirs toward their crippled relatives. A better understanding of this evolutionary immune process might lead to interventions that could artificially create more elite controllers.
HIV cure studies to date have largely attempted to encourage latent proviruses into making new viruses, in principle drawing them out of their cellular hiding places, to be eliminated by the immune system, and steadily reduce the size of the reservoir. This "shock and kill" strategy has had little success; the new study suggests it is better to qualify interventions by quantifying how much they shift the proviral reservoir from gene regions to gene deserts.
Steven Deeks -- of the University of California, San Francisco, another member of the study team -- says the new findings could help the elite controllers. Since ECs are still HIV-positive, many doctors advise this group to continue to take ARVs, which have strong side effects. If the ECs have a relatively high level of proviruses in gene deserts, it may be safe for them to stop treatment. Deeks says: "A lot of them now are getting medication they don't need."
COMMENT ON ARTICLE* ANOTHER MONTH: One of the many results of the CV19 pandemic on my personal life was that I finally got into ebooks. I have an old 11-inch tablet, and it makes a pretty good ebook reader.
On getting into ebooks, I then started to think about checking them out from the local library. I wondered how that was done, thinking: "It would be nice to have an app to read library books." I finally found out about "Hoopla", which is an ebook service for libraries, and downloaded its app. It took me a while to learn how to use it; searching for titles, for example on "Thomas Jefferson", gave me a ton of very thin books on Jefferson for kids. It turned out that browsing hierarchically -- from "biographies" to "presidents" -- got better results.
I was then tipped off to another service, named "Overdrive", which has a "Libby" app. At this point, the exercise came to a screeching halt. It turns out that anything I check out on Hoopla costs the library an average of over $2 USD. Huh? I figured ebooks would be like print books: the ebooks are purchased by the library, and then one person checks each one out at a time. Unfortunately, that's not the case, publishers making sure they get a good cut every time a book is read. It's a greedy money machine.
That ended up putting a stop to my library downloads. I could make donations to the library -- I do on occasion, I could do it more often -- to cover the cost, but it turned out the selection wasn't all that good for my own needs. It was more effective in all regards to buy either used books or ebooks from Amazon, whichever is cheaper.
* In less amusing news, Colorado has had an unprecedented fire season, with walls of flame roaring through the mountains. I am not at any great risk here in Loveland, since it's pretty much open country, but shifting winds occasionally smother the city with acrid smoke. Some mornings I get up and there's ash all over my driveway. It tends to blow away quickly.
Sometimes Sikorsky Skycrane helicopters fly in to nearby ponds to tank up for another run on a fire. I feel a bit of guilt, living in comfort while an army of fire-fighters is on the front lines -- and worse about people who have lost everything to the flames. We had some fair snow and a cold snap in late October; it slowed down the fires, but it didn't put the bigger ones out. They're not expecting the fires to be under control until December.
I will say that skepticism about climate change is clearly on the fade in Colorado, since the connection between the fires and the extended dry, hot summer in the region is unmistakeable. It wasn't so long ago that Australia was burning as well; and we'll be facing more of it in the future.
COMMENT ON ARTICLE