On May 15, ASHRAE — the association of engineers who work in heating, air conditioning, and ventilation — set out its Proposed Standard 241P, Control of Infectious Aerosols.
They are soliciting comments on it until May 26 from the public. Links and instructions for comments can be found here.
This standard, which was put together over six months — lightning speed for ASHRAE, which often takes years to develop new standards due to its painstaking process — was built on years of work by the organization on indoor air quality and included some input from public health experts.
According to ASHRAE:
The standard will address long-range transmission of infectious aerosols and provides minimum requirements for:
Equivalent outdoor air (combined effect of ventilation, filtration, and air cleaning) for use during Infection Risk Mitigation Mode
Room air distribution to reduce risk
Characterization of filter and air cleaner effectiveness and safety
Commissioning, including development and implementation of a Building Readiness Plan
System operation in Infection Risk Mitigation Mode during periods of high risk
Maintenance tasks and their minimum frequency
Residences and health care facilities
ASHRAE issued some recommendations early in the pandemic that provided guidelines for the kind of filtration that should be used in buildings to minimize transmission of airborne viruses. Those guidelines, though very good, were based on ongoing work on indoor air quality and did not include the kind of comprehensive work they brought to this new standard.
These standards, once incorporated into building codes and other regulations for buildings, will be a major step forward in making sure that the indoor air is safe to breathe. In a world in which many people spend most of their time indoors, that is a crucial element of public health.
Once my science classes progressed beyond “the parts of the cell,” I loved them. So much so that my college degree is in Biology, which entailed many classes in Physics and General and Organic Chemistry. Fast forward many decades, I had the joy to attend Launch Pad Astronomy Workshop, about which I have previously blogged. But I’ve never given up my love of Things Prehistoric. Here are two wonderful new stories:
Theropod dinosaurs — a group of bipedal, mostly meat-eating dinosaurs that included T. rex, Velociraptor and Spinosaurus — may instead have concealed their deadly chompers behind thin lips that kept their teeth hydrated and tough enough to crush bones.
Paleontologists had already suggested that T. rex may have had lips, and there has been debate whether carnivorous dinosaurs looked more like present-day crocodiles, which don’t have lips and have protruding teeth, or if they more likely resembled monitor lizards, whose large teeth are covered by scaly lips.
This time, it was the mammals that blew up. Rhino-like horse relatives that had lived in the shadow of the dinosaurs became gigantic “thunder beasts” as suddenly as an evolutionary lightning strike, new research, published Thursday (May 11) in the journal Science(opens in new tab), shows.
“Even though other mammalian groups attained large sizes before [they did], brontotheres were the first animals to consistently reach large sizes,” study first author Oscar Sanisidro(opens in new tab), a researcher with the Global Change Ecology and Evolution Research Group at the University of Alcalá in Spain. “Not only that, they reached maximum weights of 4-5 tons [3.6 to 4.5 metric tons] in just 16 million years, a short period of time from a geological perspective.”
Last year, weird “bramble snout” fossils were documented at the site called “Castle Bank,” but new research published May 1 in the journal Nature Ecology and Evolution(opens in new tab) describes the whole fossil deposit.
Hosting a myriad of soft-bodied marine creatures nd their organs, which are scarcely preserved in the fossil record, the site resembles the world-renowned Cambrian deposits of Burgess Shale in Canada and Qingjiang biota in China. The rocks of Castle Bank, however, are 50 million years younger and give researchers a unique window into how soft-bodied life diversified in the Ordovician Period (485.4 million to 443.8 million years ago), according to a statement released by Amgueddfa Cymru – Museum Wales.
Researchers believe they’ve recovered more than 170 species from the site, most of which are new to science. These include what appear to be late examples of Cambrian groups, including the weirdest wonders of evolution, the nozzle-nosed opabiniids, and early examples of animals that evolved later, including barnacles, shrimp and an unidentified six-legged insect-like creature. The rocks are also home to the fossilized digestive systems of trilobites and the eyes and brain of an unidentified arthropod, as well as preserved worms and sponges.
A spectacular trio of merging galaxies in the constellation Boötes takes center stage in this image from the NASA/ESA Hubble Space Telescope. These three galaxies are set on a collision course and will eventually merge into a single larger galaxy, distorting one another’s spiral structure through mutual gravitational interaction in the process. An unrelated foreground galaxy appears to float serenely near this scene, and the smudged shapes of much more distant galaxies are visible in the background. Image Credit: ESA/Hubble & NASA, M. Sun. Article here.
On March 1, 2023, NASA’s Juno spacecraft flew by Jupiter’s moon Io, coming within 51,500 km (32,030 miles) of the innermost and third-largest of the four Galilean moons. The stunning new images provide the best and closest view of the most volcanic moon in our Solar System since the New Horizons mission flew past Io and the Jupiter system in 2006 on its way to Pluto.
hJupiter’s moon Io, as seen by the JunoCam instrument on Juno, on March 1, 2023. Credit: NASA/JPL-Caltech/SwRI/MSSS/ processed by Kevin M. Gill.
Cleary, Io still looks like a pizza. The mottled and colorful surface comes from the volcanic activity, with hundreds of vents and calderas on the surface that create a variety of features. Volcanic plumes and lava flows across the surface show up in all sorts of colors, from red and yellow to orange and black. Some of the lava “rivers” stretch for hundreds of kilometers
Glimpsed only occasionally at the hearts of massive clusters of galaxies, ultramassive black holes are some of the largest and most elusive objects in the universe. These black hole behemoths have masses exceeding that of 10 billion suns, making them far more monstrous than even the supermassive black holes found at the centers of galaxies like the Milky Way, and their tremendous size has long perplexed astronomers.
Using a high-resolution cosmological simulation called ASTRID, the team modeled the evolution of the universe as it appeared about 11 billion years ago. In the simulation, the team witnessed the birth of an ultramassive black hole following the merger of the three galaxies. Each of these galaxies contained its own quasar, a supermassive black hole that feeds on gas and powers massive outbursts of radiation that can outshine all the stars in their host galaxies combined.
This aging and still-valuable spacecraft has been exploring the outer parts of the solar system since its launch in 1977, along with its twin sibling, Voyager 2. They each traveled slightly different trajectories. Both went past Jupiter and Saturn, but Voyager 2 continued on to Uranus and Neptune. They’re both now outside the solar system, sending back data about the regions of space they’re exploring.
Voyager 1 flew past Jupiter in March 1979, and Saturn in November 1980. After its close approaches to those two gas giants, it started a trajectory out of the solar system and entered interstellar space in 2013. That’s when it ceased to detect the solar wind and scientists began to see an increase in particles consistent with those in interstellar space.
These days, Voyager 1 is more than 157.3 astronomical units from Earth and moving out at well over 61,000 km/hour. It’s busy collecting data about the interstellar medium and radiation from distant objects. If all goes well, the spacecraft should continue sending back data for nearly a decade. After that, it should fall silent as it travels beyond the Oort Cloud and out to the stars.
Earlier this year, however, the teams attached to the Voyager 1 mission noticed that the spacecraft was sending weird readouts about its attitude articulation and control system (called AACS, for short). Essentially, the AACS was sending telemetry data all right, but it was routing it to the wrong computer, one that had failed years ago. This corrupted the data, which led to the strangely garbled messages the ground-based crew received.
Once the engineers figured out that the old, dead computer might have been part of the problem, they had a way forward. They simply told the AACS to switch over sending to the correct computer system. The good news was that it didn’t affect science data-gathering and transmission. The best news came this week: team engineers have fixed the issue with the AACS and the data are flowing normally again.
The ongoing issue with AACS didn’t set off any fault protection systems onboard the spacecraft. If it had, Voyager 1 would have gone into “safe mode” while engineers tried to figure out what happened. During the period of garbled signals, AACS continued working, which indicated that the problem was either upstream or downstream of the unit. The fact that data were garbled provided a good clue to related computer issues.
This adapted article appeared in Universe Today. Click through for the full thing.
Transgender and gender diverse youth have become more visible than ever. How does transgender history inform us about where society is at in the United States?
Jules Gill-Peterson: A lot of the rhetoric around [trans] kids frames them as totally new – most people are getting to know that there are trans youth for the first time. The visibility that we’re dealing with today is pretty unprecedented. But that doesn’t mean [transgender] people themselves haven’t existed before.
One of the challenges that anyone who’s trans faces is coming to an understanding of yourself in a culture that fundamentally doesn’t recognize that you exist. One of the most remarkable things about trans youth is that they’re able to stand up in this world that we’ve created, that gives them no reason to know who they are, and say, “Hey, actually, I know something about myself that none of the adults in my life know.”
I think history can be a really powerful grounding force to give young people a sense of lineage. It’s not like you look back in time and you see yourself reflected, by any means. But I think it can be profoundly reassuring, in a moment of not just political backlash but the general isolation that trans people face in a cis-normative society, to be able to [see] that you’re not the first person to ever go through this. [I think] that is just kind of a powerful message and one that I certainly subscribe to as an adult too, but I can imagine it’s especially important for young people.
What does “cis” mean and where does it come from?
Jules Gill-Peterson: This is actually a term from chemistry. It’s a prefix that you can put in front of words. So is the word “trans.” Trans as a prefix means across – it’s the spatial metaphor moving across something. Cis means on the same side of. At some point on the internet, people started using that word; they were looking for a word to distinguish between people who are trans and people who are not. Cisgendered came to mean that your gender identity matches what was assigned at birth. That being said, it’s not a totally kind of innocent or uncomplicated term. I’m not sure how helpful it is to think of cisgender as something that people need to own up to, for example, in a pronoun circle (when people introduce themselves by name and by the pronouns they prefer).
I think often the pressure for people to [identify] as cis doesn’t make any sense, either. It’s like, well, what makes you cisgender? Did you really go through that long process of deciding if your gender matched what’s on your birth certificate, like trans people have to deal with? I tend to use the word cis in my work to describe large historical structures that created that very obligation in the first place.
Kacie Kidd: To build off that, we as a people have a tendency to put people in boxes. And I’m sure that many of us have had the experience of not neatly fitting into a box that society ascribed to us. And I think that’s something that we all can connect to, and relate to, and understand that our job of putting people in boxes is not helpful, right? And there is no binary for most things, if not all things, and I think our realization of that helps to understand the broader [situation].
What are binders and gender-affirming procedures, and is there a right age for them?
Kacie Kidd: A binder is a garment that constricts chest tissue and has a variety of uses; elite athletes often use similar kinds of products. But [binders] can help make someone feel more in line with who they are and can help them kind of navigate the world. But the answer to your question is no, there isn’t a perfect age. But these are long, thoughtful conversations and considerations.
Jules Gill-Peterson: As a historian of medicine, one of the really interesting stories that I pulled in my book, Histories of the Transgender Child, for example, is that gender affirming medicine originated long before it was seen as gender affirming. The medical techniques used now came out of studying trans and intersex people and under really horrific, barbaric, torturous conditions. But the goal of that research was actually not to help intersex and trans people – it was to force them to appear more “normal,” but actually developed means to medically intervene into human sex and gender.
One of the interesting truths here is that there really isn’t that much of a meaningful difference. The only difference between trans medicine and non-trans medicine is who gets stigmatized for it. Who has to go get a psychiatric letter of evaluation, who has trouble getting insurance compensation? [For example,] who uses the most hormones in this country? Cisgender women and cisgender men. They just don’t have to ask for it as much. Other kinds of surgeries that are exactly the same as gender affirming surgeries are called cosmetic surgeries.
I worry about my trans daughter having regrets in the future, when going back won’t be an option.
Jules Gill-Peterson: I understand the anxiety, but I want to make the case that [regret] is a red herring that’s been planted in our mind. I think the concept of regret is often tied to this idea of “de-transitioning,” the idea that you can transition and then un-transition, which is not a very good way of thinking about it. When people do choose to de-transition, especially trans women, it is due to overwhelming social pressure discrimination and loss of social support people.
People de-transition when they lose their jobs, when their partners abandon them, when their families won’t speak to them, when they’re in dire financial straits, when they’re experiencing street harassment and criminalization, and when they don’t have the material resources they need to live. Those are the most concerning regrets.
Our children’s genders aren’t something that belong to us, right? And so our job is to support them in life and try to avoid those regrets, or to avoid the regret of going through puberty you didn’t want to go through, or having to, you know, spend years pretending to be someone you [are not]. I think those are things we should feel regretful for in society.
The Conversation U.S. on Oct. 21, 2021, hosted contributors Jules Gill-Peterson, an associate professor of history at Johns Hopkins University, and Dr. Kacie Kidd, medical director of the pediatric Gender and Sexual Development Clinic at West Virginia University Medicine Children’s Hospital, in a webinar titled “Transgender and gender-diverse teens more visible than ever: Who they are, what they need and how to talk about sensitive issues.”
This article first appeared in The Conversation and is reprinted under Creative Commons license.
The ultimate, hidden truth of the world is that it is something that we make and could just as easily make differently.
— David Graeber
This is important. This is why I’ve been reading economics. I’m trying to understand the difference between our assumptions of how things work and what the actual constraints are. There are some limits on how we can make the world, but they’re rooted in the basic laws of physics and biology — neither of which we completely understand.
From my study, I’ve begun to understand that most of the rules of economics that are currently in use are built on faulty assumptions. If we toss out those assumptions and build on ideas that are much closer to actual reality, we can, as Graeber said, make a different and better world.
Living things die. Even if we discover more and better ways to extend life, living things will still die. I don’t think we’re going to get around that one. I’m not even sure we should, despite the fact that I would still like to live forever because I want to know what happens next.
But there are environments that are good for living things, ones that are bad, and some that are toxic. To apply Graeber’s thinking here: we have allowed systems that put people in bad and toxic environments for the financial benefit of a few. We do not have to do that. If all living things die, we can’t prevent that, but we can prevent them from dying prematurely of illnesses brought on by toxic environments.
A recent study points out that four million people die prematurely every year because of air pollution brought on by making things for the consumption-oriented wealthy countries.
Many of those people are elderly and have health conditions aggravated by particle pollution, but that doesn’t mean their lives weren’t valuable. Also, while the study doesn’t mention it, I suspect many of the health conditions were caused by the air pollution in the first place.
We can build a world in which healthy lives for all is more important than profit and the assumption that those with money can do whatever they want. That, of course, means a potent environmental protection program. Continue reading “Making Things Different”…
I had an existential crisis when I was ten years old.
Okay, perhaps I was an overachiever, anxiety-wise. My class was studying the sense, and the subject of differences in individual perception came up, like it does. It’s very likely, my teacher said, that humans perceive things like color, or certain scents or tastes, differently from one another: that I might experience the color I characterize as yellow differently from you. In terms of light and spectra, the color yellow is the color yellow is the color yellow, but my experience of yellow is based on my hardware and software: that is, my eyes and brain, as well as my experiences in interpreting color.
My class had some fun with this; ten year olds are not notably sophisticated about humor, and for a day or two there was a rash of “Nice red shirt,” comments to people who weren’t wearing red, and so forth. In science class the next day, someone asked, if our experiences are all different, how can we knew that yellow is yellow? My teacher fumphed a bit and got sidetracked talking about light and the visible spectrum, and… my classmate never quite got an an answer, but I remember sitting at my desk feeling deeply unsettled.
If my color yellow was not the same as someone else’s color yellow, how could I be sure that the word yellow when I spoke it would sound like yellow to a person I was talking to? How could I make sure that anything I said or experienced was the same thing someone else heard or experienced? Short of crawling into someone else’s head, how could I ever know? Which made me feel as alone as I had ever felt in my young life. I felt suddenly like everyone–me and everyone I loved–were all just individual objects blithering through the world, crossing paths but unable to confirm our experiences. It was a kind of lonely I had never suspected existed, and I lost several nights sleep trying to devise different ways that I could confirm with someone that yellow was yellow.
And then, gradually, the anxiety diminished and I stopped trying to invent telepathy or some other way to contact and verify that the reality I live in is, in fact, consensual. I don’t think about it too much any more–although back in the 1990s I wrote a story about a man who establishes a telepathic connection with a pair of genetically engineered lions–and while he’s delighting in the connection with another being, they’re sizing him up for dinner.
When I think about it, maybe it’s just as well I don’t know what anyone else thinks is yellow.
I was – note the past tense – going to write a post about re-entry after Covid-19 vaccination and how awesome it was to give my younger daughter a hug after over a year, but then I saw this story from Science magazine and could not resist.
Did you ever wish you could see a living dinosaur? I sure did! (I still do…but from a safe distance.) As a child I loved movies with stop-action animation of dinosaurs, like the original King Kong or the Ray Harryhausen movie, The Valley of Gwangi. In high school I wrote a short novel about two teenagers and their horses who discover a hidden valley where dinosaurs still roam. Jurassic Park and its sequels blew me away, the movies even more so than the novels. The novels were longer on explanation, the movies far more powerful in vividness. The moment when Alan Grant, upon learning that Professor Hammond has created a T. rex and almost faints, that’s how I would have felt. Great acting and directing aside, these books and films spoke to a universal or near-universal human longing to see amazing charismatic animals from the distant past.
The earlier stories, at least the ones I read and watched, made no effort at a scientific basis for the present-day existence of prehistoric animals. It was all “Land That Time Forgot” hand-waving. Crichton took a different tack: dinosaurs did not persist in some undiscovered corner of or beneath the Earth: humans re-created them using DNA preserved in amber. We’ve been able to recover DNA from Pleistocene mammals, but never anything as old as 65 million years. Many scientists doubt that DNA could survive that long, no matter how preserved. When an animal dies, its DNA begins to decay. A 2012 study on moa bones showed that genetic material deteriorates at such a rate that it halves itself every 521 years. This speed would mean paleontologists can only hope to recover recognizable DNA sequences the past 6.8 million years. In 2020, Chinese Academy of Sciences paleontologist Alida Bailleul and her colleagues proposed they had found a chemical signature suggestive of DNA in a 70 million year old baby hadrosaur fossil. If confirmed, this material would be so degraded into components, not sequences. It’s also possible the chemical signature was that of bacteria, not the dinosaur itself.
The Siberian permafrost that has yielded mammoth DNA is about 2.6 million years old, but freezing turns out to be a pretty good preservative of DNA. Scientists have now been able to sequence DNA from extinct mammoths 1.2 million years ago. That’s a world record. The previous record, in 2013, was from a 750,000-year-old horse. The new study includes DNA from three species of mammoth from three time periods (1.2 million, 1 million, and 700,000 years ago) and there are all kinds of reasons to be excited about it, not just the age but the evolutionary relationships and a previously unknown type.
Which brings us to the question we’re all asking: Once we’ve sequenced this DNA, whether from mammoths, saber-toothed cats, ground sloths, or whatever – what do we do with it? What we can do now is better understand the evolution and relationships of these amazing animals. What popular media want, however, is to use the material to create living extinct species. The process of de-extinction can proceed either by cloning – taking material from a recently extinct species and replicating it – or by using ancient, fragmentary DNA. We’ve got a long way to go with either technique. Many extinct species lack contemporary surrogates to carry the artificially created embryos to term. For others, suitable habitat no longer exists (really? Where would you turn a giant ground sloth loose? A saber-toothed cat? Or would these animals exist only in the unnatural environment of zoos?) Back in 2009, Spanish scientists cloned a newly extinct Pyrenean ibex, although the clone died within a few hours of birth.
There are, however, a few good candidates for which possibly viable DNA sources exist. Species like the passenger pigeon and Carolina parakeet might fare well, given the human responsibility for their disappearance, although they might turn out to be temporally invasive species. Continue reading “Romancing the Prehistoric”…
Science news articles abound, everything from the results of carefully designed peer-reviewed research studies to fear-based rumors and anti-science biased conspiracy theories. How are we to discern which are reliable, which are hype based on misinterpretation, flawed studies, and the like, and which are clickbait nonsense?
The first thing I do is look at the source. Mediabiasfactcheck and other sites provide information as to the right-left biases and factual accuracy of a given source, although not of a particular story. Science Based Medicine is also helpful. I’ve been known to search under “Is Dr. So-and-So a quack?” and get useful answers.
I also check my own reactions: Is this too good to be true? Is it at odds with what I understand about science (my academic background is biology and health sciences)? Have I seen an article in a trusted source (such as the newsletter from Center for Science in the Public Interest) debunking this or similar claims? I’ve been also known to check with friends with special expertise in the field.
The Conversation offers some guidelines on assessing the quackery scale of science new stories. Their suggestions:
1. Has the story undergone peer review?
Scientists rely on journal papers to share their scientific results. They let the world see what research has been done, and how.
Once researchers are confident of their results, they write up a manuscript and send it to a journal. Editors forward the submitted manuscripts to at least two external referees who have expertise in the topic. These reviewers can suggest the manuscript be rejected, published as is, or sent back to the scientists for more experiments. That process is called “peer review.”
Research published in peer-reviewed journals has undergone rigorous quality control by experts. Each year, about 2,800 peer-reviewed journals publish roughly 1.8 million scientific papers. The body of scientific knowledge is constantly evolving and updating, but you can trust that the science these journals describe is sound. Retraction policies help correct the record if mistakes are discovered post-publication.
Peer review takes months. To get the word out faster, scientists sometimes post research papers on what’s called a preprint server. These often have “RXiv” – pronounced “archive” – in their name: MedRXiv, BioRXiv and so on. These articles have not been peer-reviewed and so are not validated by other scientists. Preprints provide an opportunity for other scientists to evaluate and use the research as building blocks in their own work sooner.
How long has this work been on the preprint server? If it’s been months and it hasn’t yet been published in the peer-reviewed literature, be very skeptical. Are the scientists who submitted the preprint from a reputable institution? During the COVID-19 crisis, with researchers scrambling to understand a dangerous new virus and rushing to develop lifesaving treatments, preprint servers have been littered with immature and unproven science. Fastidious research standards have been sacrificed for speed.
A last warning: Be on the alert for research published in what are called predatory journals. They don’t peer-review manuscripts, and they charge authors a fee to publish. Papers from any of the thousands of known predatory journals should be treated with strong skepticism.
2. Be aware of your own biases.
Beware of biases in your own thinking that might predispose you to fall for a particular piece of fake science news.
People give their own memories and experiences more credence than they deserve, making it hard to accept new ideas and theories. Psychologists call this quirk the availability bias. It’s a useful built-in shortcut when you need to make quick decisions and don’t have time to critically analyze lots of data, but it messes with your fact-checking skills.
A confirmation bias can be at work as well. People tend to give credence to news that fits their existing beliefs. This tendency helps climate change denialists and anti-vaccine advocates believe in their causes in spite of the scientific consensus against them.
When I’m traveling (oh, to be traveling again!), I like to wander around the place I’m visiting and fantasize about what it would be like to live there. I do the same thing staring out car or train windows.
I like to lie in bed when I first wake up and think about things. Sometimes I work on stories or essays, but sometimes I just think about something I’d like to do.
The main thing that actually gets me out of bed in the morning is the idea that once I’ve washed my face (and such) and fed the cats and made the coffee, I can sit in a comfy chair, sip my coffee, and think.
Truth be told, I think my whole life is a constant search for time to just sit and think.
So when I read this report about a scientific study that suggests most people don’t like to be alone with their thoughts, I was, to put it mildly, shocked. Especially when they reported that 67 percent of men and 25 percent of women would rather give themselves electric shocks than be alone with their thoughts.
Jupiter and Saturn, but Voyager 2 continued on to Uranus and Neptune. They’re both now outside the solar system, sending back data about the regions of space they’re exploring.
could not resist.
The Siberian permafrost that has yielded mammoth DNA is about 2.6 million years old, but freezing turns out to be a pretty good preservative of DNA. 