Ants – with their wise farming practices and efficient navigation techniques – could inspire solutions for some human problems

Leafcutter ants cultivate fungus gardens that feed sprawling colonies. Tim Flach/Stone via Getty Images

Scott Solomon, Rice University

King Solomon may have gained some of his famed wisdom from an unlikely source – ants.

According to a Jewish legend, Solomon conversed with a clever ant queen that confronted his pride, making quite an impression on the Israelite king. In the biblical book of Proverbs (6:6-8), Solomon shares this advice with his son: “Look to the ant, thou sluggard, consider her ways and be wise. Which having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest.”

While I can’t claim any familial connection to King Solomon, despite sharing his name, I’ve long admired the wisdom of ants and have spent over 20 years studying their ecology, evolution and behaviors. While the notion that ants may offer lessons for humans has certainly been around for a while, there may be new wisdom to gain from what scientists have learned about their biology. Ants have evolved highly complex social organizations.

Lessons from ant agriculture

As a researcher, I’m especially intrigued by fungus-growing ants, a group of 248 species that cultivate fungi as their main source of food. They include 79 species of leafcutter ants, which grow their fungal gardens with freshly cut leaves they carry into their enormous underground nests. I’ve excavated hundreds of leafcutter ant nests from Texas to Argentina as part of the scientific effort to understand how these ants coevolved with their fungal crops.

Much like human farmers, each species of fungus-growing ant is very particular about the type of crops they cultivate. Most varieties descend from a type of fungus that the ancestors of fungus-growing ants began growing some 55 million to 65 million years ago. Some of these fungi became domesticated and are now unable to survive on their own without their insect farmers, much like some human crops such as maize. Ants started farming tens of millions of years before humans.

Ant farmers face many of the same challenges human farmers do, including the threat of pests. A parasite called Escovopsis can devastate ant gardens, causing the ants to starve. Likewise in human agriculture, pest outbreaks have contributed to disasters like the Irish Potato Famine, the 1970 corn blight and the current threat to bananas.

Since the 1950s, human agriculture has become industrialized and relies on monoculture, or growing large amounts of the same variety of crop in a single place. Yet monoculture makes crops more vulnerable to pests because it is easier to destroy an entire field of genetically identical plants than a more diverse one.

Industrial agriculture has looked to chemical pesticides as a partial solution, turning agricultural pest management into a billion-dollar industry. The trouble with this approach is that pests can evolve new ways to get around pesticides faster than researchers can develop more effective chemicals. It’s an arms race – and the pests have the upper hand.

Ants also grow their crops in monoculture and at a similar scale – after all, a leafcutter ant nest can be home to 5 million ants, all of which feed on the fungi in their underground gardens. They, too, use a pesticide to control Escovopsis and other pests.

Yet, their approach to pesticide use differs from humans’ in one important way. Ant pesticides are produced by bacteria they allow to grow in their nests, and in some cases even on their bodies. Keeping bacteria as a living culture allows the microbes to adapt in real time to evolutionary changes in the pests. In the arms race between pests and farmers, farming ants have discovered that live bacteria can serve as pharmaceutical factories that can keep up with ever-changing pests.

Whereas recent developments in agricultural pest management have focused on genetically engineering crop plants to produce their own pesticides, the lesson from 55 million years of ant agriculture is to leverage living microorganisms to make useful products. Researchers are currently experimenting with applying live bacteria to crop plants to determine if they are effective at producing pesticides that can evolve in real time along with pests.

Improving transportation

Ants can also offer practical lessons in the realm of transportation.

Ants are notoriously good at quickly locating food, whether it’s a dead insect on a forest floor or some crumbs in your kitchen. They do this by leaving a trail of pheromones – chemicals with a distinctive smell ants use to guide their nest mates to food. The shortest route to a destination will accumulate the most pheromone because more ants will have traveled back and forth along it in a given amount of time.

In the 1990s, computer scientists developed a class of algorithms modeled after ant behavior that are very effective at finding the shortest path between two or more locations. Like with real ants, the shortest route to a destination will accumulate the most virtual pheromone because more virtual ants will have traveled along it in a given amount of time. Engineers have used this simple but effective approach to design telecommunication networks and map delivery routes.

Leafcutter ants crowding a patch of dirt
Thousands of ants can travel along the same path without causing traffic jams. Esteban Castao Solano/EyeEm via Getty Images

Not only are ants good at finding the shortest route from their nests to a source of food, thousands of ants are capable of traveling along these routes without causing traffic jams. I recently began collaborating with physicist Oscar Andrey Herrera-Sancho to study how leafcutter ants maintain such a steady flow along their foraging paths without the slowdowns typical of crowded human sidewalks and highways.

We are using cameras to track how each individual ant responds to artificial obstacles placed on their foraging trails. Our hope is that by getting a better understanding of the rules ants use to respond to both obstacles and the movement of other ants, we can develop algorithms that can eventually help program self-driving cars that never get stuck in traffic.

Look to the ant

To be fair, there are plenty of ways ants are far from perfect role models. After all, some ant species are known for indiscriminate killing, and others for enslaving babies.

But the fact is that ants remind us of ourselves – or the way we might like to imagine ourselves – in many ways. They live in complex societies with division of labor. They cooperate to raise their young. And they accomplish remarkable engineering feats – like building structures with air funnels that can house millions – all without blueprints or a leader. Did I mention their societies are run entirely by females?

There is still a lot to learn about ants. For example, researchers still don’t fully understand how an ant larva develops into either a queen – a female with wings that can live for 20 years and lay millions of eggs – or a worker – a wingless, often sterile female that lives for less than a year and performs all the other jobs in the colony. What’s more, scientists are constantly discovering new species – 167 new ant species were described in 2021 alone, bringing the total to more than 15,980.

By considering ants and their many fascinating ways, there’s plenty of wisdom to be gained.

Scott Solomon, Associate Teaching Professor of Ecology and Evolutionary Biology, Rice University

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Harnessing the brain’s immune cells to stave off Alzheimer’s and other neurodegenerative diseases

Microglia (colored green) play several essential roles in maintaining brain health and function. Gerry Shaw/Wikimedia Commons, CC BY-NC-SA

Kristine Zengeler, University of Virginia

Many neurodegenerative diseases, or conditions that result from the loss of function or death of brain cells, remain largely untreatable. Most available treatments target just one of the multiple processes that can lead to neurodegeneration, which may not be effective in completely addressing disease symptoms or progress, if at all.

But what if researchers harnessed the brain’s inherent capabilities to cleanse and heal itself? My colleagues and I in the Lukens Lab at the University of Virginia believe that the brain’s own immune system may hold the key to neurodegenerative disease treatment. In our research, we found a protein that could possibly be leveraged to help the brain’s immune cells, or microglia, stave off Alzheimer’s disease.

Challenges in treating neurodegeneration

No available treatments for neurodegenerative diseases stop ongoing neurodegeneration while also helping affected areas in the body heal and recuperate.

In terms of failed treatments, Alzheimer’s disease is perhaps the most infamous of neurodegenerative diseases. Affecting more than 1 in 9 U.S. adults 65 and older, Alzheimer’s results from brain atrophy with the death of neurons and loss of the connections between them. These casualties contribute to memory and cognitive decline. Billions of dollars have been funneled into researching treatments for Alzheimer’s, but nearly every drug tested to date has failed in clinical trials. Alzheimer’s disease leads to loss of connections between neurons and cell death.

Another common neurodegenerative disease in need of improved treatment options is multiple sclerosis. This autoimmune condition is caused by immune cells attacking the protective cover on neurons, known as myelin. Degrading myelin leads to communication difficulties between neurons and their connections with the rest of the body. Current treatments suppress the immune system and can have potentially debilitating side effects. Many of these treatment options fail to address the toxic effects of the myelin debris that accumulate in the nervous system, which can kill cells.

A new frontier in treating neurodegeneration

Microglia are immune cells masquerading as brain cells. In mice, microglia originate in the yolk sac of an embryo and then infiltrate the brain early in development. The origins and migration of microglia in people are still under study.

Microglia play important roles in healthy brain function. Like other immune cells, microglia respond rapidly to pathogens and damage. They help to clear injuries and mend afflicted tissue, and can also take an active role in fighting pathogens. Microglia can also regulate brain inflammation, a normal part of the immune response that can cause swelling and damage if left unchecked.

Microglia also support the health of other brain cells. For instance, they can release molecules that promote resilience, such as the protein BDNF, which is known to be beneficial for neuron survival and function. Microglia are the often overlooked essential workers of the brain.

But the keystone feature of microglia are their astounding janitorial skills. Of all brain cell types, microglia possess an exquisite ability to clean up gunk in the brain, including the damaged myelin in multiple sclerosis, pieces of dead cells and amyloid beta, a toxic protein that is a hallmark of Alzheimer’s. They accomplish this by consuming and breaking down debris in their environment, effectively eating up the garbage surrounding them and their neighboring cells.

Given the many essential roles microglia serve to maintain brain function, these cells may possess the capacity to address multiple arms of neurodegeneration-related dysfunction. Moreover, as lifelong residents of the brain, microglia are already educated in the best practices of brain protection. These factors put microglia in the perfect position for researchers to leverage their inherent abilities to protect against neurodegeneration.

New data in both animal models and human patients points to a previously underappreciated role microglia also play in the development of neurodegenerative disease. Many genetic risk factors for diseases like Alzheimer’s and multiple sclerosis are strongly linked to abnormal microglia function. These findings support an accumulating number of animal studies suggesting that disruptions to microglial function may contribute to neurologic disease onset and severity.

This raises the next logical question: How can researchers harness microglia to protect the nervous system against neurodegeneration?

Engaging the magic of microglia

In our lab’s recent study, we keyed in on a crucial protein called SYK that microglia use to manipulate their response to neurodegeneration.

Our collaborators found that microglia dial up the activity of SYK when they encounter debris in their environment, such as amyloid beta in Alzheimer’s or myelin debris in multiple sclerosis. When we inhibited SYK function in microglia, we found that twice as much amyloid beta accumulated in Alzheimer’s mouse models and six times as much myelin debris in multiple sclerosis mouse models.

Blocking SYK function in the microglia of Alzheimer’s mouse models also worsened neuronal health, indicated by increasing levels of toxic neuronal proteins and a surge in the number of dying neurons. This correlated with hastened cognitive decline, as the mice failed to learn a spatial memory test. Similarly, impairing SYK in multiple sclerosis mouse models exacerbated motor dysfunction and hindered myelin repair. These findings indicate that microglia use SYK to protect the brain from neurodegeneration.

But how does SYK protect the nervous system against damage and degeneration? We found that microglia use SYK to migrate toward debris in the brain. It also helps microglia remove and destroy this debris by stimulating other proteins involved in cleanup processes. These jobs support the idea that SYK helps microglia protect the brain by charging them to remove toxic materials.

Finally, we wanted to figure out if we could leverage SYK to create “super microglia” that could help clean up debris before it makes neurodegeneration worse. When we gave mice a drug that boosted SYK function, we found that Alzheimer’s mouse models had lower levels of plaque accumulation in their brains one week after receiving the drug. This finding points to the potential of increasing microglia activity to treat Alzheimer’s disease.

Light micrograph of microglia cells
Of the many brain cells (shown in black), giving microglia a boost could help them more effectively clean up debris in the brain. Jose Luis Calvo Martin & Jose Enrique Garcia-Mauriño Muzquiz/iStock via Getty Images Plus

The horizon of microglia treatments

Future studies will be necessary to see whether creating a super microglia cleanup crew to treat neurodegenerative diseases is beneficial in people. But our results suggest that microglia already play a key role in preventing neurodegenerative diseases by helping to remove toxic waste in the nervous system and promoting the healing of damaged areas.

It’s possible to have too much of a good thing, though. Excessive inflammation driven by microglia could make neurologic disease worse. We believe that equipping microglia with the proper instructions to carry out their beneficial functions without causing further damage could one day help treat and prevent neurodegenerative disease.

Uncharted Brain, podcast series

Listen to The Conversation’s podcast series Uncharted Brain: Decoding Dementia to find out more about the latest research unlocking clues to the ongoing mystery of how dementia works in the brain. Find all episodes via The Anthill podcast.

Kristine Zengeler, Ph.D. Candidate in Neuroscience, University of Virginia

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Toilets spew invisible aerosol plumes with every flush – here’s the proof, captured by high-powered lasers

Aerosol plumes from commercial toilets can rise 5 feet above the bowl. John Crimaldi/Scientific Reports, CC BY-NC-ND

John Crimaldi, University of Colorado Boulder

Every time you flush a toilet, it releases plumes of tiny water droplets into the air around you. These droplets, called aerosol plumes, can spread pathogens from human waste and expose people in public restrooms to contagious diseases.

Scientific understanding of the spread of aerosol plumes – and public awareness of their existence – has been hampered by the fact that they are normally invisible. My colleagues Aaron True, Karl Linden, Mark Hernandez, Lars Larson and Anna Pauls and I were able to use high-power lasers to illuminate these plumes, enabling us to image and measure the location and motion of spreading aerosol plumes from flushing commercial toilets in vivid detail. This video compares the visibility of an aerosol plume after a flush without and with lasers in a lab.

Going up instead of down

Toilets are designed to efficiently empty the contents inside the bowl through a downward motion into the drain pipe. In the flush cycle, water comes into forceful contact with the contents inside the bowl and creates a fine spray of particles suspended in air.

We found that a typical commercial toilet generates a strong upward jet of air with velocities exceeding 6.6 feet per second (2 meters per second), rapidly carrying these particles up to 5 feet (1.5 meters) above the bowl within eight seconds of the start of the flush.

Diagram of jet-siphonic toilet
Water streams forcefully into the toilet bowl during a flush cycle. SouthHamsian/Wikimedia Commons, CC BY-NC-SA

To visualize these plumes, we set up a typical lidless commercial toilet with a flushometer-style valve found throughout North America in our lab. Flushometer valves use pressure instead of gravity to direct water into the bowl. We used special optics to create a thin vertical sheet of laser light that illuminated the region from the top of the bowl to the ceiling. After flushing the toilet with a remote electrical trigger, the aerosol particles scatter enough laser light to become visible, allowing us to use cameras to image the plume of particles.

Even though we expected to see these particles, we were still surprised by the strength of the jet ejecting the particles from the bowl.

A related study used a computational model of an idealized toilet to predict the formation of aerosol plumes, with an upward transport of particles at speeds above the bowl approaching 3.3 feet per second (1 meter per second), which is about half of what we observed with a real toilet.

Why lasers?

Scientists have known for decades that flushing toilets can release aerosol particles into the air. However, experimental studies have largely relied on devices that sampled the air at fixed locations to determine the number and size of particles toilets produce.

While these earlier approaches can confirm the presence of aerosols, they provide little information about the physics of the plumes: what they look like, how they spread and how fast they move. This information is critical to develop strategies to mitigate the formation of aerosol plumes and reduce their capacity to transmit disease. This video shows Aaron True monitoring the live image data of a flushing toilet plume on a computer screen.

As an engineering professor whose research focuses on interactions between fluid physics and ecological or biological processes, my laboratory specializes in using lasers to determine how various things are transported by complex fluid flows. In many cases, these things are invisible until we illuminate them with lasers.

An advantage of using laser light to measure fluid flows is that, unlike a physical probe, light does not alter or disrupt the very thing you are trying to measure. Furthermore, using lasers to make invisible things visible helps people, as visual creatures, better understand complexities in the fluid environment they live in.

Aerosols and disease

Aerosol particles containing pathogens are important human disease vectors. Smaller particles that remain suspended in air for a period of time can expose people to respiratory diseases like influenza and COVID-19 through inhalation. Larger particles that settle quickly on surfaces can spread intestinal diseases like norovirus through contact with the hands and mouth.

Toilet bowl water contaminated by feces can have pathogen concentrations that persist after dozens of flushes. But it is still an open question as to whether toilet aerosol plumes present a transmission risk.

While we were able visually and quantitatively to describe how aerosol plumes move and disperse, our work does not directly address how toilet plumes transmit disease, and this remains an ongoing aspect of research.

Limiting toilet plume spread

Our experimental methodology provides a foundation for future work to test a range of strategies to minimize the risk of exposure to diseases from flushing toilets. This could include assessing changes to aerosol plumes emanating from new toilet bowl designs or flush valves that change the duration or intensity of the flush cycle.

Meanwhile, there are ways to reduce human exposure to toilet plumes. An obvious strategy is to close the lid prior to flushing. However, this does not completely eliminate aerosol plumes, and many toilets in public, commercial and health care settings do not have lids. Ventilation or UV disinfection systems could also mitigate exposure to aerosol plumes in the bathroom.

John Crimaldi, Professor of Civil, Environmental and Architectural Engineering, University of Colorado Boulder

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Nasal vaccines promise to stop the COVID-19 virus before it gets to the lungs – an immunologist explains how they work

Nasal vaccines for COVID-19 are still in early development. Paul Biris/Moment via Getty Images

Michael W. Russell, University at Buffalo

The Pfizer-BioNTech and Moderna mRNA vaccines have played a large role in preventing deaths and severe infections from COVID-19. But researchers are still in the process of developing alternative approaches to vaccines to improve their effectiveness, including how they’re administered. Immunologist and microbiologist Michael W. Russell of the University at Buffalo explains how nasal vaccines work, and where they are in the development pipeline.

How does the immune system fight pathogens?

The immune system has two distinct components: mucosal and circulatory.

The mucosal immune system provides protection at the mucosal surfaces of the body. These include the mouth, eyes, middle ear, the mammary and other glands, and the gastrointestinal, respiratory and urogenital tracts. Antibodies and a variety of other anti-microbial proteins in the sticky secretions that cover these surfaces, as well as immune cells located in the lining of these surfaces, directly attack invading pathogens.

The circulatory part of the immune system generates antibodies and immune cells that are delivered through the bloodstream to the internal tissues and organs. These circulating antibodies do not usually reach the mucosal surfaces in large enough amounts to be effective. Thus mucosal and circulatory compartments of the immune system are largely separate and independent.

What are the key players in mucosal immunity?

The immune components people may be most familiar with are proteins known as antibodies, or immunoglobulins. The immune system generates antibodies in response to invading agents that the body identifies as “non-self,” such as viruses and bacteria.

Antibodies bind to specific antigens: the part or product of a pathogen that induces an immune response. Binding to antigens allows antibodies to either inactivate them, as they do with toxins and viruses, or kill bacteria with the help of additional immune proteins or cells.

The mucosal immune system generates a specialized form of antibody called secretory IgA, or SIgA. Because SIgA is located in mucosal secretions, such as saliva, tears, nasal and intestinal secretions, and breast milk, it is resistant to digestive enzymes that readily destroy other forms of antibodies. It is also superior to most other immunoglobulins at neutralizing viruses and toxins, and at preventing bacteria from attaching to and invading the cells lining the surfaces of organs.

There are also many other key players in the mucosal immune system, including different types of anti-microbial proteins that kill pathogens, as well as immune cells that generate antibody responses. Mucus is one of the central secretions of the mucosal immune system.

How does the COVID-19 virus enter the body?

Almost all infectious diseases in people and other animals are acquired through mucosal surfaces, such as by eating or drinking, breathing or sexual contact. Major exceptions include infections from wounds, or pathogens delivered by insect or tick bites.

The virus that causes COVID-19, SARS-CoV-2, enters the body via droplets or aerosols that get into your nose, mouth or eyes. It can cause severe disease if it descends deep into the lungs and causes an overactive, inflammatory immune response.

This means that the virus’s first contact with the immune system is probably through the surfaces of the nose, mouth and throat. This is supported by the presence of SIgA antibodies against SARS-CoV-2 in the secretions of infected people, including their saliva, nasal fluid and tears. These locations, especially the tonsils, have specialized areas that specifically trigger mucosal immune responses.

Some research suggests that if these SIgA antibody responses form as a result of vaccination or prior infection, or occur quickly enough in response to a new infection, they could prevent serious disease by confining the virus to the upper respiratory tract until it is eliminated.

How do nasal vaccines work?

Vaccines can be given through mucosal routes via the mouth or nose. This induces an immune response through areas that stimulate the mucosal immune system, leading mucosal secretions to produce SIgA antibodies.

There are several existing mucosal vaccines, most of them taken by mouth. Currently only one, the flu vaccine, is delivered nasally.

In the case of nasal vaccines, the viral antigens intended to stimulate the immune system would be taken up by immune cells within the lining of the nose or tonsils. While the exact mechanisms by which nasal vaccines work in people have not been thoroughly studied, researchers believe they work analogously to oral mucosal vaccines. Antigens in the vaccine induce B cells in mucosal sites to mature into plasma cells that secrete a form of IgA. That IgA is then transported into mucosal secretions throughout the body, where it becomes SIgA.

If the SIgA antibodies in the nose, mouth or throat target SARS-CoV-2, they could neutralize the virus before it can drop down into the lungs and establish an infection. Nasal vaccines could provide a more approachable alternative to injections for patients leery of needles.

What advantage do mucosal vaccines have against COVID-19?

I believe that arguably the best way to protect an individual against COVID-19 is to block the virus at its point of entry, or at least to confine it to the upper respiratory tract, where it might inflict relatively little damage.

Breaking chains of viral transmission is crucial to controlling epidemics. Researchers know that COVID-19 spreads during normal breathing and speech, and is exacerbated by sneezing, coughing, shouting, singing and other forms of exertion. Because these emissions mostly originate from saliva and nasal secretions, where the predominant form of antibody present is SIgA, it stands to reason that secretions with a sufficiently high level of SIgA antibodies against the virus could neutralize and thereby diminish its transmissibility.

Existing vaccines, however, do not induce SIgA antibody responses. Injected vaccines primarily induce circulating IgG antibodies, which are effective in preventing serious disease in the lungs. Nasal vaccines specifically induce SIgA antibodies in nasal and salivary secretions, where the virus is initially acquired, and can more effectively prevent transmission.

Nasal vaccines may be a useful supplement to injected vaccines in hot spots of infection. Since they don’t require needles, they might also help overcome vaccine hesitancy due to fear of injections.

How close are researchers to creating a nasal COVID-19 vaccine?

There have been over 100 oral or nasal COVID-19 vaccines in development around the world.

Most of these have been or are currently being tested in animal models. Many have reported successfully inducing protective antibodies in the blood and secretions, and have prevented infection in these animals. However, few have been successfully tested in people. Many have been abandoned without fully reporting study details.

According to the World Health Organization, 14 nasal COVID-19 vaccines are in clinical trials as of late 2022. Reports from China and India indicate that nasal or inhaled vaccines have been approved in these countries. But little information is publicly available about the results of the studies supporting approval of these vaccines.

Michael W. Russell, Professor Emeritus of Microbiology and Immunology, University at Buffalo

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Twitter in 2022: 5 essential reads about the consequences of Elon Musk’s takeover of the microblogging platform

It’s safe to say that Elon Musk has transformed Twitter. Jonathan Raa/NurPhoto via Getty Images

Eric Smalley, The Conversation

You would be forgiven for growing numb to the almost daily assault of headlines proclaiming the latest stunning development involving Elon Musk’s tenure as owner and manager of Twitter. The microblogging platform has seen a rise in hate speech and technical problems as media reports say up to 75% of the staff has been cut since he took over.

In December 2022, unsettling news about Twitter included the disbanding of the company’s Trust and Safety Council, the conspiracy theories and score settling of the “Twitter Files,” QAnon’s Musk-inspired revival, the suspension of the Twitter accounts of journalists covering the company, and a brief ban on links to rival social media platforms such as Instagram, Facebook and Mastodon.

Beneath these headlines lie crucial questions about the nature, role and state of social media in society. Prompted by Musk’s acquisition of Twitter, The Conversation published several articles exploring these issues. These articles from our archive look at the effects of content management, the dangers of COVID-19 misinformation, Twitter’s underappreciated nature as a data source, Black Twitter’s vital role in social justice movements, and the difficulties of starting over in a post-Twitter world.

1. Free speech, bias and manipulation

Among Musk’s stated motivations for buying Twitter was to address his claim that the platform was biased against figures on the right. Musk did not offer any data to support this.

Twitter’s own researchers, who had access to data not available outside the company, found that the opposite is the case – the platform is biased in favor of right-leaning voices.

Musk said at the time he made his bid for the company that he intended to make Twitter a platform for free speech, and that free speech on Twitter was being stifled by excessive content moderation.

Again, research shows that the opposite is the case. To the extent that Twitter is an arena for free speech, it is an arena that is readily manipulated. “Astroturf” causes, trolling and misinformation are facilitated by bots and malicious users that appear to be the digital equivalent of crowds gathering around fabricated outrage.

Indiana University social media researcher Filippo Menczer has found that this manipulation has become sophisticated, with coordinated networks of users and bots manipulating Twitter’s algorithms to artificially increase or decrease the popularity of content. Twitter has attempted to rein in this abuse in recent years through content moderation, and weakening these moderation policies “may make abuse rampant again,” he wrote.

2. Medical misinformation unbound

In November 2022, Twitter quietly posted notice that it would no longer enforce its policy against COVID-19 misinformation. Fighting medical misinformation on social media has been an uphill battle, and the outcome has life-and-death consequences.

Michigan State University social media researcher Anjana Susarla noted that social media facilitates the spread of misinformation and amplifies content that’s likely to trigger heightened emotions. There’s considerable evidence that misinformation on social media reduces vaccine uptake and is making it more difficult for society to reach herd immunity, she wrote. Twitter’s rollback of its ban on COVID-19 misinformation is a threat to public health.

Another issue is that what happens on Twitter doesn’t stay on Twitter. Anti-vaccine content and medical misinformation generally “can spill over into other online platforms,” hampering those platforms’ efforts to combat misinformation, Susarla wrote.

3. Diamonds in the mud

As Twitter devolves and degrades, there is a possibility that the platform, at least in pre-Musk form, could disappear. While few are likely to lament the loss of a playground for trolls and a breeding ground for misinformation, Susarla spelled out some of the unique and valuable services Twitter has provided.

Every public tweet is archived and accessible, which makes for a treasure trove of data about collective human behavior. This data is very valuable for researchers and policymakers, she wrote. For example, public health researchers have found associations between tweeting about HIV and incidence of HIV, and with geotagged tweets researchers are able to assess the health of people in particular neighborhoods.

Twitter has also been a vital arena for crowdsourcing, Susarla noted. For example, during natural disasters and other emergencies, Twitter “has been a great venue for crowdsourced eyewitness data,” she wrote. And Twitter has been invaluable in the field of open-source intelligence (OSINT), “particularly for tracking down war crimes.”

4. Black Twitter

Twitter has also been invaluable as a venue for crowdsourcing about another type of threat: police brutality, particularly against Black people. In 2018, 28% of Twitter’s users in the U.S. were Black, and about 1 in 5 Black Americans were on Twitter, according to Nielsen.

This digital community in Twitter, dubbed Black Twitter, circulates topics, stories and images that directly relate to and affect the Black community, noted Emerson College communications scholar Deion Scott Hawkins. In particular, Twitter is often used to document and upload videos of police brutality. “For instance, the video of George Floyd’s death in police custody was first publicized on Twitter, and then mainstream news circulated the footage,” he wrote.

three young people stand in a plaza holding handwritten protest signs
Twitter has been a crucial conduit for documenting police brutality against Black people. Stephen Melkisethian/Flickr, CC BY-NC-ND

Losing Black Twitter would mean losing robust, rapid and authentic information sharing on police brutality within the Black community, Hawkins observed. “Black Twitter and the information it provides is literally a matter of life and death,” he wrote.

5. Pack your bags, but to where?

The changes Twitter is undergoing have prompted many people to leave the platform, and more to consider doing so. The potential depopulation of the social media platform is a scenario that University of Colorado Boulder information science researcher Casey Fiesler has seen – and studied – before.

There is “essentially zero chance” that the majority of Twitter users can simply move to another platform and resume business as usual, she noted. Migrating to another platform is an uphill battle. “When social media platforms fall, sometimes the online communities that made their homes there fade away, and sometimes they pack their bags and relocate to a new home,” she wrote.

Previous social media platform migrations have shown the challenges: content loss, fragmented communities, broken social networks and shifted community norms, according to Fiesler. “But Twitter isn’t one community, it’s a collection of many communities, each with its own norms and motivations,” she wrote. “Some communities might be able to migrate more successfully than others.”

Editor’s note: This story is a roundup of articles from The Conversation’s archives.

Eric Smalley, Science + Technology Editor, The Conversation

This article is republished from The Conversation under a Creative Commons license. Read the original article.


China’s new space station opens for business in an increasingly competitive era of space activity

Three taikonauts rode aboard the Shenzhou 15 mission on their way to China’s new Tiangong space station. Xinhua News Agency via Getty Images

Eytan Tepper, Indiana University and Scott Shackelford, Indiana University

The International Space Station is no longer the only place where humans can live in orbit.

On Nov. 29, 2022, the Shenzhou 15 mission launched from China’s Gobi Desert carrying three taikonauts – the Chinese word for astronauts. Six hours later, they reached their destination, China’s recently completed space station, called Tiangong, which means “heavenly palace” in Mandarin. The three taikonauts replaced the existing crew that helped wrap up construction. With this successful mission, China has become just the third nation to operate a permanent space station.

China’s space station is an achievement that solidifies the country’s position alongside the U.S. and Russia as one of the world’s top three space powers. As scholars of space law and space policy who lead the Indiana University Ostrom Workshop’s Space Governance Program, we have been following the development of the Chinese space station with interest.

Unlike the collaborative, U.S.-led International Space Station, Tiangong is entirely built and run by China. The successful opening of the station is the beginning of some exciting science. But the station also highlights the country’s policy of self-reliance and is an important step for China toward achieving larger space ambitions among a changing landscape of power dynamics in space.

A diagram of the space station.
The Tiangong space station is much smaller than the International Space Station and consists of three modules. Shujianyang/Wikimedia Commons, CC BY-SA

Capabilities of a Chinese station

The Tiangong space station is the culmination of three decades of work on the Chinese manned space program. The station is 180 feet (55 meters) long and is comprised of three modules that were launched separately and connected in space. These include one core module where a maximum of six taikonauts can live and two experiment modules for a total of 3,884 cubic feet (110 cubic meters) of space, about one-fifth the size of the International Space Station. The station also has an external robotic arm, which can support activities and experiments outside the station, and three docking ports for resupply vehicles and manned spacecraft.

Like China’s aircraft carriers and other spacecraft, Tiangong is based on a Soviet-era design – it is pretty much a copy of the Soviet Mir space station from the 1980s. But the Tiangong station has been heavily modernized and improved.

The Chinese space station is slated to stay in orbit for 15 years, with plans to send two six-month crewed missions and two cargo missions to it annually. The science experiments have already begun, with a planned study involving monkey reproduction commencing in the station’s biological test cabinets. Whether the monkeys will cooperate is an entirely different matter.

A person in a space suit outside of a space station.
This image, captured from a video feed at the Beijing Aerospace Center on Nov. 17, 2022, shows taikonauts working on the Tiangong station. Xinhua News Agency via Getty Images

Science and a steppingstone

The main function of the Tiangong station is to perform research on life in space. There is a particular focus on learning about the growth and development of different types of plants, animals and microorganisms, and there are more than 1,000 experiments planned for the next 10 years.

Tiangong is strictly Chinese made and managed, but China has an open invitation for other nations to collaborate on experiments aboard Tiangong. So far, nine projects from 17 countries have been selected.

Although the new station is small compared to the 16 modules of the International Space Station, Tiangong and the science done aboard will help support China’s future space missions. In December 2023, China is planning to launch a new space telescope called Xuntian. This telescope will map stars and supermassive black holes among other projects with a resolution about the same as the Hubble Space Telescope but with a wider view. The telescope will periodically dock with the station for maintenance.

China also has plans to launch multiple missions to Mars and nearby comets and asteroids with the goal of bringing samples back to Earth. And perhaps most notably, China has announced plans to build a joint Moon base with Russia – though no timeline for this mission has been set. The three-person crew of taikonauts greets the crew already aboard the Tiangong station in early December 2022.


A new era in space is unfolding. The Tiangong station is beginning its life just as the International Space Station, after more than 30 years in orbit, is set to be decommissioned by 2030.

The International Space Station is the classic example of collaborative ideals in space – even at the height of the Cold War, the U.S. and the Soviet Union came together to develop and launch the beginnings of the space station in the early 1990s. By comparison, China and the U.S. have not been so jovial in their orbital dealings.

In the 1990s, when China was still launching U.S. satellites into orbit, concerns emerged that China was accidentally acquiring – or stealing – U.S. technology. These concern in part led to the Wolf Amendment, passed by Congress in 2011, which prohibits NASA from collaborating with China in any capacity. China’s space program was not mature enough to be part of the construction of the International Space Station in the 1990s and early 2000s. By the time China had the ability to contribute to the International Space Station, the Wolf Amendment prevented it from doing so.

It remains to be seen how the map of space collaboration will change in the coming years. The U.S.-led Artemis Program that aims to build a self-sustaining habitat on the Moon is open to all nations, and 19 countries have joined as partners so far. China has also recently opened its joint Moon mission with Russia to other nations. This was partly driven by cooling Chinese-Russian relations but also due to the fact that because of the war in Ukraine, Sweden, France and the European Space Agency canceled planned missions with Russia.

As tensions on Earth rise between China, Russia and the West, and some of that jockeying spills over into space, it remains to be seen how the decommissioning of the International Space Station and operation of the Tiangong station will influence the China-U.S. relationship.

An event like the famous handshake between U.S. astronauts and Russian cosmonauts while orbiting Earth in 1975 is a long way off, but collaboration between the U.S. and China could do much to cool tensions on and above the Earth.

Eytan Tepper, Visiting Assistant Professor of Space Governance, Indiana University and Scott Shackelford, Professor of Business Law and Ethics, Indiana University

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Sepsis is one of the most expensive medical conditions in the world – new research clarifies how it can lead to cell death

Bacteria (clusters of light pink, surrounded by larger magenta blood cells) can cause deadly infections, but overreactive immune responses can deliver the lethal blow. Scharvik/iStock via Getty Images Plus

Alexander (Sasha) Poltorak, Tufts University and Hayley Muendlein, Tufts University

Sepsis is a life-threatening condition arising from the body’s overreactive response against an infection, leading it to injure its own tissues and organs. The first known reference to “sepsis” dates back more than 2,700 years, when the Greek poet Homer used it as a derivative of the word “sepo,” meaning “I rot.”

Despite dramatic improvements in understanding the immunological mechanisms behind sepsis, it still remains a major medical concern, affecting 750,000 people in the U.S. and nearly 50 million people globally each year. Sepsis accounted for 11 million deaths worldwide in 2017, and is the most expensive medical condition in the U.S., costing over tens of billions of dollars annually.

We are researchers who study how certain types of bacteria interact with cells during infections. We wanted to understand exactly how an overreactive immune response can result in detrimental and even lethal effects like sepsis. In our newly published research, we discovered the cells and molecules that potentially trigger death from sepsis. Sepsis results from a potentially lethal overreactive immune response to infection.

TNF in autoimmunity and sepsis

The body’s response to infection starts when immune cells recognize components of the invading pathogen. These cells then release molecules like cytokines that help eliminate the infection. Cytokines are a broad group of small proteins that recruit other immune cells to the site of infection or injury.

While cytokines play an essential role in the immune response, excessive and uncontrolled cytokine production can lead to a dangerous cytokine storm associated with sepsis. Cytokine storms were first seen in the context of graft versus host disease, arising from transplant complications. They can also occur during viral infections, including COVID-19. This uncontrolled immune response can lead to multi-organ failure and death.

Among the hundreds of cytokines that exist, tumor necrosis factor, or TNF, stands tall as the most potent and the most studied for nearly the past 50 years.

Tumor necrosis factor owes its name to its ability to induce tumor cells to die when the immune system is stimulated by a bacterial extract called Coley’s toxin, named after the researcher who identified it over a century ago. This toxin was later recognized to be lipopolysaccharide, or LPS, a component of the outer membrane of certain types of bacteria. LPS is the strongest known trigger of TNF, which, once on alert, aids in the recruitment of immune cells to the infection site to eliminate invading bacteria. Severe COVID-19 infections can trigger cytokine storms.

In normal conditions, TNF promotes beneficial processes such as cell survival and tissue regeneration. However, TNF production must be tightly regulated to avoid sustained inflammation and continuous proliferation of immune cells. Uncontrolled TNF production can lead to the development of rheumatoid arthritis and similar inflammatory conditions.

In infection conditions, TNF must also be tightly regulated to prevent excessive tissue and organ damage from inflammation and an overactive immune response. When TNF is left uncontrolled during infections, it can lead to sepsis. For several decades, studies of septic shock were modeled by investigating responses to bacterial LPS. In this model, LPS activates certain immune cells that trigger the production of inflammatory cytokines, in particular TNF. This then leads to excessive immune cell proliferation, recruitment and death, ultimately resulting in tissue and organ damage. Too strong of an immune response is not a good thing.

Researchers have shown that blocking TNF activity can effectively treat numerous autoimmune diseases, including rheumatoid arthritis, psoriatic arthritis and inflammatory bowel disease. Use of TNF blockers has dramatically increased in the past decades, reaching a market size of roughly $40 billion.

However, TNF blockers have been unsuccessful in preventing the cytokine storm that can arise from COVID-19 infections and sepsis. This is in part because exactly how TNF triggers its toxic effects on the body is still poorly understood despite years of research.

How TNF can be lethal

Studying sepsis might provide some clues as to how TNF mediates how the immune system responds to infection. In acute inflammatory conditions such as sepsis, TNF blockers are less able to address TNF overproduction. However, studies in mice show that neutralizing TNF can prevent the death of the animal from bacterial LPS. Although researchers do not yet understand the reason for this discrepancy, it highlights the need for further understanding how TNF contributes to sepsis.

Blood cells made in the bone marrow, or myeloid cells, are known to be the major producers of TNF. So we wondered if myeloid cells also mediate TNF-induced death.

Illustration of TNF bound to a cell membrane
TNF (blue) is implicated in a number of inflammatory diseases. selvanegra/iStock via Getty Images Plus

First, we identified which particular molecules might offer protection from TNF-induced death. When we injected mice with a lethal dose of TNF, we found that mice lacking either TRIF or CD14, two proteins typically associated with immune responses to bacterial LPS but not TNF, had improved survival. This finding parallels our earlier work identifying these factors as regulators of a protein complex that controls cell death and inflammation in response to LPS.

Next, we wanted to figure out which cells are involved in TNF-induced death. When we injected a lethal dose of TNF in mice lacking the two proteins in two specific types of myeloid cells, neutrophils and macrophages, mice had reduced symptoms of sepsis and improved survival. This finding positions macrophages and neutrophils as major triggers for TNF-mediated death in mice.

Our results also suggest TRIF and CD14 as potential treatment targets for sepsis, with the ability to both reduce cell death and inflammation.

Alexander (Sasha) Poltorak, Professor of Immunology, Tufts University and Hayley Muendlein, Research Assistant Professor of Immunology, Tufts University

This article is republished from The Conversation under a Creative Commons license. Read the original article.


Better sleep for kids starts with better sleep for parents – especially after holiday disruptions to routines

When sleep routines have gone haywire, there are things to keep in mind to help the whole family reset. Catherine Falls/Moment via Getty Images

Erika Bocknek, Wayne State University

Everyone knows that sleep is critical for growing children and their mental and physical health. Regular, high-quality sleep habits help children consolidate memory and learn better. A lack of sleep contributes to childhood depression, anxiety and even risk of suicide, along with physical health problems, including risk of injury. The challenge is making sure kids log those valuable zzz’s.

There are three main components of high-quality sleep for children. First, they need enough total hours – sleep duration. Sleep quality is important, too – sleeping soundly during the night with few disruptions or awakenings. And, finally, there’s sleep timing – essentially, a consistent schedule, with bedtime and risetime about the same across the whole week.

Even when you know how important good sleep is, it’s easy for sleep duration, quality and timing to get knocked off track. It can happen for infrequent reasons, such as the pleasant chaos of a holiday, or the disturbances that accompany pandemic life. Healthy sleep habits are hard to maintain for everyday mundane reasons, too, such as parent-child disagreement, busy schedules and older children’s leisurely weekend behavior. But there are ways for families to get sleep back on course.

As a child development researcher and family therapist, I study parenting and family behaviors that create healthy environments for children’s sleep patterns. In particular, I help parents to develop consistent and nurturing routines. Sleep patterns are set early, and parents play an important role in nurturing children’s perspectives and attitudes. Here’s the overarching advice I share with families, no matter the age of their kids.

yawning woman holding a glowing phone
Grown-ups can’t ignore their own sleep hygiene while expecting kids to stick with the rules. Boy_Anupong/Moment via Getty Images

1. Set and model family values about sleep

Children are observant learners. They pay very careful attention to both the spoken and unspoken rules of their clan.

To get everyone in the household sleeping well, sleep can’t be something that only children must care about, while adults who have freedom and power joke about their own unhealthy habits. If sleep seems like punishment, rather than the gift for health that it is, children will be likely to resist it.

Adults need to talk the talk and walk the walk that sleep is a priority for everyone in the family. Be a role model. If you’ve fallen into a habit of binge-watching TV into the wee hours, for instance, work on reining that in. Use positive language about your own sleep. Pay attention to what you say, and what you communicate through your own habits, reinforcing that it’s important to the whole family to get sleep and have energy for the next day. Don’t make the mistake of discussing bedtime as a chance for adults to get distance from the kids.

2. Know your child

Remember, every kid is unique, so don’t expect one-size-fits-all sleep advice to work universally. A child’s temperament plays a significant role in the duration, quality and timing of their sleep. For instance, a feistier child may not adapt as quickly to a sleep schedule over the first year. And temperament is a pretty stable part of who your child is and will continue to be.

A parent’s job is to keep encouraging routines and setting limits – but with ongoing warmth and sensitivity about the characteristics of the one-of-a-kind child you have.

When you’re exhausted and struggling with a child’s behavior, it can be hard to stay positive. My recommendation is to use the daytime hours wisely as investment in your relationship. Be proactive about noticing the good in your kid. Remind yourself that your child is their own person, learning in lots of ways throughout the day, and that child development is a marathon, not a sprint, for positive change. Sleep regressions or other sleep difficulties, like night awakening or changes in sleep habits, are opportunities for growth, not punishment.

By laying this groundwork, it becomes easier to tap into a positive and respectful attitude during times of stress. Remind yourself that change over time is more important than control over a given moment. After all, strained parent-child relationships can actually lead to continuing sleep and behavioral problems in young children.

boy leaning into man who's kissing his head
Strengthening your relationship during the day supports healthy sleep at night. Hill Street Studios/DigitalVision via Getty Images

3. Aim for consistency, with some flexibility

In my practice, I see two common – but opposite – mistakes that parents make around sleep.

First, many parents let go of rules and boundaries altogether. Often this happens as a result of what children bring to the equation: personal temperament or age-related phenomena. For instance, the peak in behavioral aggression that can come in toddlerhood or the shift in sleep timing that comes in adolescence can cause some parents to just throw in the towel and give up.

Alternatively, other parents become rigid. They see conflict around sleep as a struggle for power that the adult must win.

I argue that balance is key. Parents should adopt a consistent approach that fits with the sleep values they’ve been clear about all along. But they must also remain flexible to help children adapt routines to their own unique needs.

For example, all children at all ages should have a regular bedtime and risetime. However, parents may be open to a collaborative plan with older children about what those times should be, or attending to patterns and cues from younger children, working on a reasonable compromise that takes into account the needs of the individual child. Parents’ message about the importance of sleep should never waiver.

4. Manage household issues that influence sleep

child lying in bed holding up tablet
Blue light before bed prevents a young body from winding down. Dejan_Dundjerski/iStock via Getty Images Plus

Research shows that certain problems outside the bedroom create immediate and long-term risk for children’s sleep quality. These include exposure to second-hand smoke, excessive or evening-timed blue light exposure from screens and conflict in the home. Dealing with these factors will likely pay dividends when it comes to your kids getting a good night’s sleep.

Good sleep hygiene is a family affair. It’s never too late to nudge habits in a good direction and recommit to everyone getting the rest they need. Your child’s sleep habits can be a critical building block of lifelong wellness.

Erika Bocknek, Associate Professor of Educational Psychology, Wayne State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.


NASA’s Artemis 1 mission to the Moon sets the stage for routine space exploration beyond Earth’s orbit – here’s what to expect and why it’s important

NASA is going back to the Moon. NASA/Bill Ingalls

Jack Burns, University of Colorado Boulder

NASA’s Space Launch System rocket lifted off from the Kennedy Space Center in Cape Canaveral, Florida, in the early hours of Nov. 16, 2022. The rocket carried the Orion Crew Capsule as the centerpiece of the Artemis 1 mission. The journey to the Moon and back is a shakedown cruise with no people aboard – it will test how the Orion Crew Capsule holds up in space. The mission is a key step toward returning humans to the Moon after a half-century hiatus. The launch was initially scheduled for the morning of Aug. 29, 2022, but was postponed three times, twice for technical reasons and once for Hurricane Ian.

The spacecraft is scheduled to travel to the Moon, deploy some small satellites and then settle into orbit. NASA aims to practice operating the spacecraft, test the conditions crews will experience on and around the Moon, and assure everyone that the spacecraft and any occupants can safely return to Earth.

The Conversation asked Jack Burns, a professor and space scientist at the University of Colorado Boulder and former member of the Presidential Transition Team for NASA, to describe the mission, explain what the Artemis program promises to do for space exploration, and reflect on how the space program has changed in the half-century since humans last set foot on the lunar surface.

How does Artemis 1 differ from the other rockets being launched routinely?

Artemis 1 is the first flight of the new Space Launch System. This is a “heavy lift” vehicle, as NASA refers to it. It is the most powerful rocket engine ever flown to space, even more powerful than Apollo’s Saturn V system that took astronauts to the Moon in the 1960s and ‘70s.

It’s a new type of rocket system, because it has both a combination of liquid oxygen and hydrogen main engines and two strap-on solid rocket boosters derived from the space shuttle. It’s really a hybrid between the space shuttle and Apollo’s Saturn V rocket.

You can listen to more articles from The Conversation, narrated by Noa, here.

Testing is very important, because the Orion Crew Capsule is going to be getting a real workout. It will be in the space environment of the Moon, a high-radiation environment, for a month. And, very importantly, it will be testing the heat shield, which protects the capsule and its occupants, when it comes back to the Earth at 25,000 miles per hour. This will be the fastest capsule reentry since Apollo, so it’s very important that the heat shield function well.

This mission is also carrying a series of small satellites that will be placed in orbit of the Moon. Those will do some useful precursor science, everything from looking further into the permanently shadowed craters where scientists think there is water to just doing more measurements of the radiation environment, seeing what the effects will be on humans for long-term exposure.

A diagram showing the earth, moon and flight path of a spacecraft
The plan is for Artemis 1 to lift off, travel to the Moon, deploy satellites, orbit the Moon, return to Earth, safely enter the atmosphere and splash down in the ocean. NASA

What’s the goal of the Artemis project? What’s coming up in the series of launches?

The mission is a first step toward Artemis 3, which is going to result in the first human missions to the Moon in the 21st century and the first since 1972. Artemis 1 is an uncrewed test flight.

Artemis 2, which is scheduled to launch a few years after that, will have astronauts on board. It, too, will be an orbital mission, very much like Apollo 8, which circled the Moon and came back home. The astronauts will spend a longer time orbiting the Moon and will test everything with a human crew.

And, finally, that will lead to a journey to the surface of the Moon in which Artemis 3 – sometime middecade – will rendezvous with the SpaceX Starship and transfer crew. Orion will remain in orbit, and the lunar Starship will take the astronauts to the surface. They will go to the south pole of the Moon to look at an area scientists haven’t explored before to investigate the water ice there.

Artemis is reminiscent of Apollo. What has changed in the past half-century?

The reason for Apollo that Kennedy envisioned initially was to beat the Soviet Union to the Moon. The administration didn’t particularly care about space travel, or about the Moon itself, but it represented an audacious goal that would clearly put America first in terms of space and technology.

The downside of doing that is the old saying “You live by the sword, you die by the sword.” When the U.S. got to the Moon, it was basically game over. The United States beat the Russians. So it put some flags down and did some science experiments. But pretty quickly after Apollo 11, within a few more missions, Richard Nixon canceled the program because the political objectives had been met.

a large rocket with two boosters attached to its sides standing between two massive gantries
NASA’s new Space Launch System is seen here being moved from the rocket assembly building to a launchpad. NASA

So fast-forward 50 years. This is a very different environment. The U.S. is not doing this to beat the Russians or the Chinese or anybody else, but to begin a sustainable exploration beyond Earth’s orbit.

The Artemis program is driven by a number of different goals. It includes in situ resource utilization, which means using resources at hand like water ice and lunar soil to produce food, fuel and building materials.

The program is also helping to establish a lunar and space economy, starting with entrepreneurs, because SpaceX is very much part of this first mission to the surface of the Moon. NASA doesn’t own the Starship but is buying seats to allow astronauts to go to the surface. SpaceX will then use the Starship for other purposes – to transport other payloads, private astronauts and astronauts from other countries.

Fifty years of technology development means that going to the Moon now is much less expensive and more technologically feasible, and much more sophisticated experiments are possible when you just figure the computer technology. Those 50 years of technological advancement have been a complete game-changer. Almost anybody with the financial resources can send spacecraft to the Moon now, though not necessarily with humans.

NASA’s Commercial Lunar Payload Services contracts private companies to build uncrewed landers to go to the Moon. My colleagues and I have a radio telescope that’s scheduled to go to the Moon on one of the landers in March. That just wouldn’t have been possible even 10 years ago. Artemis is an ambitious program, but technology has advanced tremendously in the 50 years since humans last went to the Moon.

What other changes does Artemis have in store?

The administration has said that in that first crewed flight, on Artemis 3, there will be at least one woman and very likely a person of color. They may be one and the same. There may be several.

I’m looking forward to seeing more of that diversity, because young kids today who are looking up at NASA can say, “Hey, there’s an astronaut who looks like me. I can do this. I can be part of the space program.”

This article was updated on Nov. 16, 2022, to indicate that NASA launched the rocket.

Jack Burns, Professor of Astrophysical and Planetary Sciences, University of Colorado Boulder

This article is republished from The Conversation under a Creative Commons license. Read the original article.


What is Mastodon? A social media expert explains how the ‘federated’ network works and why it won’t be a new Twitter

Twitter users who are fleeing to the social media platform Mastodon are finding it to be a different animal. Davide Bonaldo/SOPA Images/LightRocket via Getty Images

Brian C. Keegan, University of Colorado Boulder

In the wake of Elon Musk’s noisy takeover of Twitter, people have been looking for alternatives to the increasingly toxic microblogging social media platform. Many of those fleeing or hedging their bets have turned to Mastodon, which has attracted hundreds of thousands of new users since Twitter’s acquisition.

Like Twitter, Mastodon allows users to post, follow people and organizations, and like and repost others’ posts.

But while Mastodon supports many of the same social networking features as Twitter, it is not a single platform. Instead, it’s a federation of independently operated, interconnected servers. Mastodon servers are based on open-source software developed by German nonprofit Mastodon gGmbH. The interconnected Mastodon servers, along with other servers that can “talk” to Mastodon servers, are collectively dubbed the “fediverse.”

Mastodon U.

A key aspect of the fediverse is that each server is governed by rules set by the people who operate it. If you think of the fediverse as a university, each Mastodon server is like a dorm.

Which dorm you’re initially assigned to can be somewhat random but still profoundly shapes the kind of conversations you overhear and the relationships you form. You can still interact with people who live in other dorms, but the leaders and rules in your dorm shape what you can do.

If you’re particularly unhappy with your dorm, you can move to a new housing situation – another dorm, a sorority, an apartment – that is a better fit, and you bring your relationships with you. But you are then subject to the rules of the new place where you live. There are hundreds of Mastodon servers, called instances, where you can set up your account, and these instances have different rules and norms for who can join and what content is permitted.

In contrast, social media platforms like Twitter and Facebook put everyone in a single, gigantic dorm. As millions or billions of people joined, the companies running these platforms added more floors and bedrooms. Everyone could communicate with each other and theoretically join each other’s conversations within the dorm, but everyone also has to live under the same rules.

If you didn’t like or didn’t follow the rules, you had to leave the megadorm, but you were not able to bring your relationships with you to your new housing – a different social media platform – or talk to people who stayed in your original megadorm. These platforms tapped into the resulting fear of missing out to lock people into a highly surveilled dorm where their otherwise private behavior was mined to sell ads.

Screenshot of a microblogging app
Mastodon supports all the familiar social media functions: posting, liking, reposting and following. Eugen Rochko via Wikimedia Commons

Incentives for good behavior

The big social media companies sell ads to pay for two primary services: the technical infrastructure of hardware and software that lets users access the platform, and the social infrastructure of usability, policy and content moderation that keeps the platform in line with users’ expectations and rules.

In the Mastodon collection of servers, if you don’t like what someone is doing, you can cut ties and move to another server but keep the relationships you already made. This removes the fear of missing out that could otherwise lock users into a server with other people’s bad behavior.

There are a few factors that should put Mastodon servers under strong pressure to actively and responsibly moderate the behavior of their members. First, most servers don’t want other servers cutting ties entirely, so there is strong reputational pressure to police members’ behavior and not tolerate trolls and harassers.

Second, people can migrate between servers relatively easily, so the server administrators can compete to provide the best moderation experience that attracts and keeps people around.

Third, the technical and financial costs of creating a new server are much greater than the costs of moderating a server. This should limit the number of new servers cropping up to evade bans, which would avoid the endless “whack-a-mole” challenge of new spam and troll accounts that the big social media platforms have to deal with.

Not all milk and honey

The federated server model on Mastodon also has potential drawbacks. First, finding a server to join on Mastodon can be hard, especially when a flood of people trying to find servers leads to the creation of waitlists, and the rules and values of the people running a server aren’t always easy to find.

Second, there are significant financial and technical challenges with maintaining servers that grow with the number of members and their activity. After the honeymoon is over, Mastodon users should be prepared for membership fees, NPR-style fundraising campaigns or podcast-style promotional ads to cover server hosting costs that can go into the hundreds of dollars per month per server.

Third, despite calls for newspapers, universities and governments to host their own servers, there are complicated legal and professional questions that could severely limit public institutions’ abilities to moderate their “dorms” effectively. Professional societies with their own methods of verification and established codes of conduct and ethics may be better equipped to host and moderate Mastodon servers than other types of institutions.

Fourth, the current “nuclear option” of servers entirely cutting ties with other servers leaves little room for repairing relations and reengagement. Once the tie between two servers is severed, it would be difficult to renew it. This situation could drive destabilizing user migrations and reinforce polarizing echo chambers.

Finally, there are tensions between longtime Mastodon users and newcomers around content warnings, hashtags, post visibility, accessibility and tone that are different from what was popular on Twitter.

Still, with Twitter melting down and the long-standing issues with the major social media platforms, for many people the new land of Mastodon and the fediverse doesn’t have to be all milk and honey. Step-by-step instructions for joining Mastodon.

Brian C. Keegan, Assistant Professor of Information Science, University of Colorado Boulder

This article is republished from The Conversation under a Creative Commons license. Read the original article.