Dans les torrents, des insectes tissent de minuscules filets de pêche qui inspirent de nouveaux matériaux

Source: The Conversation – in French – By Christophe Mori, Maitre de conférences, Université de Corse Pascal-Paoli

Au fond des torrents et des ruisseaux, de petites larves d’insecte construisent des filets pour attraper leur nourriture et font preuve d’une intelligence remarquable pour s’adapter au courant. Des comportements qui inspirent nos propres innovations techniques.


Imaginez-vous au bord d’un torrent, où l’eau surgit avec une force capable d’emporter des pierres. Au fond de ce tumulte, des larves de quelques millimètres, non seulement survivent, mais prospèrent en bâtissant des pièges ingénieux pour capturer leur nourriture. Sur leurs filets de soie de 2 à 3 cm de diamètre, on les voit s’affairer, le nettoyant régulièrement des petits morceaux de feuilles, de bois, des algues et des petits organismes qui s’y piègent.

Ces larves sont des hydropsychés, des insectes de l’ordre des trichoptères. Après avoir vécu sous la forme de larve dans une rivière pendant un à deux ans, ils s’envolent une fois leur forme adulte atteinte, durant laquelle il ressemble à un petit papillon de nuit. La fin de leur vie sera alors très courte, de 10 à 20 jours seulement.

Les hydropsychés, petits ingénieurs des ruisseaux

Les hydropsychés sont des insectes aquatiques ingénieux qui construisent ces tamis de soie pour filtrer passivement leur nourriture dans les eaux courantes. Cette capacité démontre une réelle intelligence comportementale, d’autant qu’ils savent s’ajuster aux flux de nutriments et qu’elles défendent leur territoire. Les larves tricotent des mailles fines (entre 1/50 e et 1/10 e de mm) adaptées à la vitesse du courant : plus il est fort, plus elles fabriquent un filet aux mailles serrées pour résister au courant ! Et lorsqu’il est obstrué ou endommagé, par exemple par des sédiments ou un courant trop fort, elles sont capables de le reconstruire ou le modifier. Il reste à comprendre le déclencheur précis de cette adaptation – est-ce purement génétique ou influencé par l’apprentissage individuel ?

Un si petit organisme, de seulement 1 à 2 cm de long, et qui possède un cerveau de 0,3 mm3 est non seulement capable de concevoir son filet avec une maille variable, de l’ancrer au substrat et de l’orienter face au courant. Mais il est sait aussi repousser ses congénères qui pourraient s’installer trop près et lui voler sa pêche ! Pour cela, les hydropsychés utilisent des ultrasons (d’une fréquence de 64 à 100 kHz, bien au-delà de ce que l’oreille humaine peut percevoir) pour indiquer leur présence à leurs voisins.

À la manière des cigales, les larves génèrent ces sons par stridulation, en frottant certaines parties de leur corps entre elles. Cette technique acoustique facilite leur navigation dans le tumulte sonore des eaux agitées, et est associée à des signaux chimiques tels que des phéromones qui facilitent l’identification et l’interaction sociale dans des milieux agités.

Des petites larves témoin de la qualité des eaux

Dans les communautés aquatiques, les hydropsychés coexistent avec d’autres espèces filtreuses, comme des larves de diptères, pour optimiser les ressources. Elles influencent la stabilité des cours d’eau en modulant les sédiments organiques et les différents flux nutritifs. Les organismes filtreurs sont de véritables nettoyeurs des rivières et des torrents, de petits ingénieurs qui améliorent la qualité des eaux. Ils sont déterminants dans l’architecture des écosystèmes d’eaux courantes, puisqu’ils constituent des proies pour les autres organismes, et sont donc à la base des chaînes alimentaires.

D’un point de vue morphologique, les branchies spécialisées des hydropsychés leur permettent d’extraire l’oxygène même dans des conditions tumultueuses ou déficientes. Cependant, ce sont aussi des organismes fragiles. Cela en fait de bons indicateurs biologiques qui servent aux scientifiques à évaluer la qualité de l’eau et les impacts de la pollution ou du changement climatique.

De plus, les hydropsyché inspirent le biomimétisme pour des technologies filtrantes durables, des colles aquatiques et la recherche médicale. Contrairement à la soie de ver à soie ou d’araignée, celle des hydropsychés est synthétisée sous l’eau, ce qui lui confère une résistance exceptionnelle à l’humidité, une haute élasticité et une biodégradabilité contrôlée. Ces caractéristiques en font un modèle idéal pour développer des biomatériaux innovants en médecine.

Quand l’hydropsyché inspire nos propres innovations

Dans ce monde aquatique en perpétuel mouvement, ces organismes démontrent que la survie dépend d’une vigilance constante et de l’adaptation face à l’instabilité. L’humanité peut s’inspirer de cette résilience et, plus spécifiquement, des stratégies de ces petits insectes aquatiques. La soie des larves d’hydropsychés intéresse la recherche, car elle adhère facilement aux surfaces immergées tout en restant flexible. Elle présente également une résistance mécanique jusqu’à plusieurs fois celle de l’acier à poids égal, n’induit pas de réactions immunitaires fortes et est biodégradable sans laisser de résidus toxiques.

En imitant la composition de la soie des larves d’hydropsyché, les scientifiques développent des colles synthétiques qui fonctionnent en milieu humide, comme dans le corps humain. Ces adhésifs pourraient révolutionner la chirurgie en permettant de refermer des tissus mous (comme le foie ou le cœur) sans points de suture, réduisant les risques d’infection et accélérant la guérison. Des prototypes sont déjà testés pour sceller des vaisseaux sanguins ou réparer des organes internes.

Le filet adaptable des hydropsychés inspire aussi des filtres intelligents qui ajustent leur porosité selon le débit d’eau et la taille des particules, et qui seraient utiles dans les usines de traitement des eaux et les stations d’épuration. Ce composé intéresse aussi les industries marines, pour créer des matériaux qui absorberaient l’énergie des vagues sans se briser, prolongeant la durée de vie des structures. Cela pourrait notamment être exploité par le secteur de l’énergie, pour les éoliennes marines ou les hydroliennes.

Les habitants des cours d’eau : un exemple à suivre

En nous inspirant de ce petit ingénieur, nous ouvrons des voies pour des avancées concrètes. Les solutions les plus élégantes et durables ne viennent pas toujours de laboratoires, mais souvent de la nature elle-même, où l’ingénieuse simplicité du vivant surpasse notre créativité. Et à l’instar des communautés d’organismes fluviaux qui se soutiennent mutuellement, les sociétés humaines doivent établir des réseaux solidaires pour affronter l’incertitude. La remarquable résilience de ces larves nous exhorte à repenser nos modes de vie, en mettant l’accent sur une adaptation préventive plutôt que sur une réaction tardive.

En fin de compte, les hydropsychés et les organismes aquatiques en général nous offrent un exemple à suivre : dans un environnement instable, la survie réside dans la diversité des adaptations et une réelle persévérance. Dans un monde en mutation, elle n’est pas innée, mais elle peut être cultivée. Ces organismes nous montrent que même dans l’agitation structurelle permanente, la vie persiste. En protégeant les écosystèmes fluviaux, nous préservons non seulement la biodiversité, mais aussi un trésor d’inspirations pour un avenir plus résilient et innovant.


Cet article est publié dans le cadre de la Fête de la science (qui a lieu du 3 au 13 octobre 2025), dont The Conversation France est partenaire. Cette nouvelle édition porte sur la thématique « Intelligence(s) ». Retrouvez tous les événements de votre région sur le site Fetedelascience.fr.

The Conversation

Christophe Mori ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

ref. Dans les torrents, des insectes tissent de minuscules filets de pêche qui inspirent de nouveaux matériaux – https://theconversation.com/dans-les-torrents-des-insectes-tissent-de-minuscules-filets-de-peche-qui-inspirent-de-nouveaux-materiaux-271044

From early cars to generative AI, new technologies create demand for specialized materials

Source: The Conversation – USA – By Peter Müllner, Distinguished Professor in Materials Science and Engineering, Boise State University

The development of new computing technologies drives the demand for improved materials. Yuichiro Chino/Moment via Getty Images

Generative artificial intelligence has become widely accepted as a tool that increases productivity. Yet the technology is far from mature. Large language models advance rapidly from one generation to the next, and experts can only speculate how AI will affect the workforce and peoples’ daily lives.

As a materials scientist, I am interested in how materials and the technologies that derive from them affect society. AI is one example of a technology driving global change – particularly through its demand for materials and rare minerals.

But before AI evolved to its current level, two other technologies exemplified the process created by the demand for specialized materials: cars and smartphones.

Often, the mass adoption of a new invention changes human behavior, which leads to new technologies and infrastructures reliant upon the invention. In turn, these new technologies and infrastructures require new or improved materials – and these often contain critical minerals: those minerals that are both essential to the technology and strain the supply chain.

The unequal distribution of these minerals gives leverage to the nations that produce them. The resulting power shifts strain geopolitical relations and drive the search for new mineral sources. New technology nurtures the mining industry.

The car and the development of suburbs

At the beginning of the 20th century, only 5 out of 1,000 people owned a car, with annual production around a few thousand. Workers commuted on foot or by tram. Within a two-mile radius, many people had all they needed: from groceries to hardware, from school to church, and from shoemakers to doctors.

Then in 1913, Henry Ford transformed the industry by inventing the assembly line. Now, a middle class family could afford a car: Mass production cut the price of the Model T from US$850 in 1908 to $360 in 1916. While the Great Depression dampened the broad adoption of the car, sales began to increase again after the end of World War II.

A black and white photo of two men in an old car.
Henry Ford at wheel, with John Burroughs and Thomas Edison in back seat of a Model T.
Bettmann/Contributor via Getty Images

With cars came more mobility, and many people moved farther away from work. In the 1940s and 1950s, a powerful highway lobby that included oil, automobile and construction interests promoted federal highway and transportation policies, which increased automobile dependence. These policies helped change the landscape: Houses were spaced farther apart, and located farther away from the urban centers where many people worked. By the 1960s, two-thirds of American workers commuted by car, and the average commute had increased to 10 miles.

Public policy and investment favored suburbs, which meant less investment in city centers. The resulting decay made living in downtown areas of many cities undesirable and triggered urban renewal projects.

An overhead shot of a neighborhood made up of neat lines of houses and roads.
Access to cars led to more spread-out neighborhoods, like this one in Milton, Ontario.
SimonP/Wikimedia Commons, CC BY-SA

Long commutes added to pollution and expenses, which created a demand for lighter, more fuel-efficient cars. But building these required better materials.

In 1970, the entire frame and body of a car was made from one steel type, but by 2017, 10 different, highly specialized steels constituted a vehicle’s light-weight form. Each steel contains different chemical elements, such as molybdenum and vanadium, which are mined only in a few countries.

While the car supply chain was mostly domestic until the 1970s, the car industry today relies heavily on imports. This dependence has created tension with international trade partners, as reflected by higher tariffs on steel.

The cell phone and American life

The cell phone presents another example of a technology creating a demand for minerals and affecting foreign policy. In 1983, Motorola released the DynaTAC, the first commercial cellular phone. It was heavy, expensive and its battery lasted for only half an hour, so few people had one. Then in 1996, Motorola introduced the flip phone, which was cheaper, lighter and more convenient to use. The flip phone initiated the mass-adoption of cell phones. However, it was still just a phone: Unlike today’s smartphones, all it did was send and receive calls and texts.

A large, clunky phone.
The Motorola DynaTAC 8000X was the first commercially available cellphone. With innovations and better materials, cellphones later became smaller, more lightweight and adopted touch screens.
Redrum0486/Wikimedia Commons, CC BY-SA

In 2007, Apple redefined communication with the iPhone, inventing the touch screen and integrating an internet navigator. The phone became a digital hub for navigating, finding information and building an online social identity. Before smartphones, mobile phones supplemented daily life. Now, they structure it.

In 2000, fewer than half of American adults owned a cellphone, and nearly all who did it only sporadically. In 2024, 98% of Americans over the age of 18 reported owning a cellphone, and over 90% owned a smartphone.

Without the smartphone, most people cannot fulfill their daily tasks. Many individuals now experience nomophobia: They feel anxious without a cellphone.

Around three quarters of all stable elements are represented in the components of each smartphone. These elements are necessary for highly specialized materials that enable touch screens, displays, batteries, speakers, microphones and cameras. Many of these elements are essential for at least one function and have an unreliable supply chain, which makes them critical.

An infographic showing the elements used in each component of a smartphone
Smartphones contain around 80% of all known stable chemical elements, including some rare earth metals.
Andy Brunning/Compound Interest 2023, CC BY-NC-ND

Critical materials and AI

Critical materials give leverage to countries that have a monopoly in mining and processing them. For example, China has gained increased power through its monopoly on rare earth elements. In April 2025, in response to U.S. tariffs, China stopped exporting rare earth magnets, which are used in cellphones. The geopolitical tensions that resulted demonstrate the power embodied in the control over critical minerals.

Six small piles of minerals.
Piles of rare earth oxides praseodymium, cerium, lanthanum, neodymium, samarium and gadolinium.
Peggy Greb/USDA-ARS

The mass adoption of AI technology will likely change human behavior and bring forth new technologies, industries and infrastructure on which the U.S. economy will depend. All of these technologies will require more optimized and specialized materials and create new material dependencies.

By exacerbating material dependencies, AI could affect geopolitical relations and reorganize global power.

America has rich deposits of many important minerals, but extraction of these minerals comes with challenges. Factors including slow and costly permitting, public opposition, environmental concerns, high investment costs and an inadequate workforce all can prevent mining companies from accessing these resources. The mass adoption of AI is already adding pressure to overcome these factors and increase responsible domestic mining.

While the path from innovation to material dependence spanned a century for cars and a couple of decades for cell phones, the rapid advancement of large language models suggests that the scale will be measured in years for AI. The heat is already on.

The Conversation

Peter Müllner received funding from federal, state, and private organizations including the National Science Foundation, the Department of Energy, the Department of Defense, the National Institutes of Health, the Idaho Global Entrepreneurial Mission, the Micron Foundation, and the Osher Lifelong Learning Institute.

ref. From early cars to generative AI, new technologies create demand for specialized materials – https://theconversation.com/from-early-cars-to-generative-ai-new-technologies-create-demand-for-specialized-materials-269241

Trump administration’s immigrant detention policy broadly rejected by federal judges

Source: The Conversation – USA – By Cassandra Burke Robertson, Professor of Law and Director of the Center for Professional Ethics, Case Western Reserve University

Federal agents search for undocumented immigrants in Chicago on Nov. 6, 2025. Scott Olson/Getty Images

In federal courtrooms across America, a pattern has emerged in cases in which immigrants are being rounded up and jailed without a hearing. That’s a departure from fundamental constitutional protections in the U.S. that provide the right to a hearing before indefinite imprisonment.

In response, federal judges are systematically rejecting the Trump administration’s attempt to drastically expand who can be locked up without a hearing while awaiting deportation proceedings.

The Trump White House policy has been challenged in at least 362 cases in federal district courts, according to a recent ruling by U.S. District Judge Lewis A. Kaplan. Challengers have prevailed in 350 of those cases – decided by over 160 different judges sitting in about 50 different courts across the United States.

Behind those numbers are thousands of people whose freedom hangs in the balance while courts decide whether their imprisonment is lawful.

Trump administration officials claim they are targeting only “the worst of the worst” in immigration enforcement. Yet nearly three-quarters of people detained had no criminal history at all. Of those with criminal histories, many involved only minor offenses such as traffic violations.

The immigrants are in civil immigration proceedings to determine whether they can remain in the United States. Yet under the administration’s new policy, many are being held in jail-like facilities indefinitely, including “state-run prisons located in remote areas, soft-sided tent structures, military bases, and even in prisons in other countries,” according to a report from the Migration Policy Institute think tank.

As a law professor who studies due process in immigration proceedings, I view the overwhelming judicial consensus against this policy as the federal courts performing their essential constitutional function: checking executive overreach. The courts are enforcing fundamental due process protections.

Whether this consensus will prevail, however, depends on appeals courts and, ultimately, the Supreme Court.

Men dressed in military gear stand near a car.
U.S. Customs and Border Patrol Commander Gregory Bovino, center, stands with agents in Metairie, La., on Dec. 3, 2025.
Adam Gray/AFP via Getty Images

A radical reinterpretation

The current controversy centers on a policy shift the Department of Homeland Security implemented in July 2025.

In an internal memo, DHS reinterpreted decades-old immigration law to classify virtually all undocumented immigrants in the U.S. as “applicants for admission” who are subject to mandatory detention under the Immigration and Nationality Act.

For 30 years, this provision applied primarily to people apprehended at the border shortly after entering the country. The new interpretation extends it to anyone present in the U.S. illegally. That includes people who entered years or decades ago, have established families and businesses and are pursuing legal pathways to remain in the U.S.

The practical effect of the change is that people who were previously entitled to request release on bond while their deportation cases proceeded are now subject to automatic, indefinite detention without court review of whether their imprisonment is justified.

Courts overwhelmed by petitions

Within months of the July policy announcement, more than 700 emergency habeas petitions – legal challenges to unlawful imprisonment – reached federal courts nationwide.

In Michigan alone, U.S. District Judge Hala Jarbou – a Trump appointee – received more than 100 individual cases from detainees challenging their imprisonment. Then, 97 additional detainees filed a joint lawsuit. Cases arose across the country as immigrants who were arrested at workplaces, courthouses or during routine check-ins with immigration officers asked federal courts to order their release or grant them bond hearings.

The Trump administration has fought these cases on multiple fronts. It has argued that the detention policy is lawful and that federal courts lack jurisdiction to review it at all. The government has invoked provisions of the Immigration and Nationality Act that it claims strip courts of jurisdiction over certain immigration decisions.

Protesters gather in front of a federal building.
Protesters gather outside an Immigration and Customs Enforcement processing facility in Broadview, Ill., on Nov. 21, 2025.
AP Photo/Nam Y. Huh

But federal judges have largely rejected these jurisdictional arguments. They have found that courts retain the power to review whether detentions comply with the Constitution and federal law.

As one district court judge explained, accepting the government’s position would mean the executive branch could detain noncitizens indefinitely without ever having to justify that detention to a court. It’s a result that would raise “serious constitutional concerns” about suspending habeas corpus, the fundamental right to challenge unlawful imprisonment.

Judge Kaplan similarly concluded that the “current administration’s unilateral decision that all noncitizens … are to be mandatorily detained affords to such individuals no process, let alone due process. It is unconstitutional.”

An explanation on what “due process” means.

The policy’s ripple effects extend beyond the courts.

Immigration and Customs Enforcement detained a record 66,000 people in November 2025 – more than any previous administration had ever held at one time. The American Immigration Council, which advocates for immigration rights, documented 23 deaths in ICE detention during fiscal year 2025. The previous four years combined saw 24 such deaths.

A nationwide remedy

The piecemeal nature of hundreds of individual court rulings creates its own problems. Each emergency petition requires rushed briefing and a hearing. That strains the courts and detained immigrants’ ability to secure representation. Outcomes can vary based on which judge hears a case, creating geographic disparities in who remains detained and who is released.

That’s why the November decision in Maldonado Bautista v. Santacruz is potentially transformative. U.S. District Judge Sunshine S. Sykes certified a nationwide class of noncitizens subject to the policy and separately ruled that the government’s interpretation of the law was wrong – detainees are entitled to bond hearings. Combined with the nationwide class certification, this ruling could require the Trump administration to provide bond hearings to thousands of people currently in mandatory detention.

But implementation has been uneven. Immigration judges – who are Justice Department employees, not independent federal judges – have responded inconsistently to Judge Sykes’ order.

In a recent immigration court decision in Memphis, Tenn., a judge denied a bond hearing request. The judge stated that further guidance from the Executive Office for Immigration Review, a Department of Justice office, was required before complying with Sykes’ order.

Attorneys representing the class say they’ve seen similar resistance from some immigration judges, while others have begun granting bond hearings. They plan to return to federal court in January 2026 to present evidence of this confusion and seek further relief.

The near-unanimous rejection by federal judges – insulated from political pressure by lifetime appointments – demonstrates why the Constitution grants judges life tenure. Federal courts remain the final check when executive action threatens fundamental due process rights.

The Conversation

Cassandra Burke Robertson does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. Trump administration’s immigrant detention policy broadly rejected by federal judges – https://theconversation.com/trump-administrations-immigrant-detention-policy-broadly-rejected-by-federal-judges-271076

2026’s abortion battles will be fought more in courthouses and FDA offices than at the voting booth

Source: The Conversation – USA – By Rachel Rebouché, Professor of Law, The University of Texas at Austin

Medication abortions are increasingly common in states with abortion bans. Anti-abortion forces are pushing the courts and the White House to gut that access. Charlie Neibergall/AP Images

In 2026, the biggest battles over abortion will not be at the polls.

There will be a few contested measures on state ballots. Next year, Nevada’s government will ask residents to approve constitutional protection for abortion rights for the second time, as required by state law. The same measure passed in 2024 with just over 64% of the vote.

Virginians will likely see a similar ballot initiative. In November 2025, voters there cemented a majority for Democrats in the state legislature, and the House of Delegates is expected to put forth an abortion rights ballot measure to voters in 2026.

Anti-abortion proponents in Missouri want to undo an amendment protecting abortion rights that voters passed in 2024. They’re advancing a new measure that could strip residents of the reproductive rights that are now constitutionally enshrined.

However, the most consequential questions about abortion in 2026 could be answered at the federal level, by the Trump administration or in the courts. As a scholar of reproductive health law, I’m watching how federal judges and agencies respond to conservative efforts to restrict or end people’s access to mailed abortion medication.

Medication abortion in the courts

Over 25 years ago, the Food and Drug Administration approved mifepristone – one of two drugs commonly paired together to end a pregnancy. Since that time, medication abortion has been closely regulated by the FDA and is under attack.

In 2022, the Alliance for Hippocratic Medicine, a coalition of anti-abortion physicians, sued the FDA for approving mifepristone in 2000 and for each time the agency eased a restriction on mifepristone thereafter, in 2016 and 2021. The complaint argued that the FDA failed to consider evidence establishing the harm caused by medication abortion – claims roundly rejected by decades of rigorous, peer-reviewed research.

The Supreme Court in 2024 ruled that the Alliance for Hippocratic Medicine lacked standing to sue because FDA regulation of medication abortion caused no actual injury to the doctors it represented, who do not prescribe mifepristone or perform abortions.

Yet the case lives on in lower federal courts. There is ongoing litigation, and politicians are taking up the fight over mailed medication abortion.

Kansas, Missouri and Idaho intervened in the Alliance lawsuit in 2023, seeking to establish standing, and Louisiana sued the FDA in a separate case challenging the FDA’s regulation of mifepristone.

The pending actions focus on the FDA’s decision in 2021 to lift the requirement that patients pick up mifepristone in person, which has permitted patients to receive medication abortion by mail. These states claim this development is dangerous and threatens their right to enforce their abortion bans.

In October 2025, a federal court in Hawaii came to a different conclusion. The court concluded that because mifepristone is very safe, the FDA must reconsider whether the drug necessitates any restrictions at all.

The politics of medication abortion

The dispute over medication abortion is playing out in Washington, D.C., too.

In 2025, 51 Republican senators and 22 Republican attorneys general asked the FDA to reinstate the 2021 in-person restriction and upend the transit of abortion pills.

In response to Republicans’ push to restrict or withdraw the availanlity of mifepristone, 47 Democratic senators and 20 attorneys general issued letters supporting mifepristone’s safety. The letters questioned a pledge by Health and Human Services Secretary Robert F. Kennedy Jr. and his FDA chief to commence a “review” of the drug. The Democratic senators’ letter pressed the agency to remove all remaining restrictions on mifepristone.

In early December, Bloomberg reported that the FDA had quietly postponed its planned mifepristone “review” until after the 2026 midterm elections.

The battle over telehealth abortion care

Decades of research demonstrates that medication abortion is safe and effective. When commenced before 10 weeks’ gestation, the two-drug method is effective about 98% of the time. Complications, such as infection or hemorrhage, are rare; they occur in perhaps a fraction of a percent of all medication abortions.

Yet courts and legislators cannot agree on basic facts, in part due to widespread disinformation about abortion care, and anti-abortion forces have waged a concerted national campaign to stop mailed abortion pills.

Today, no part of the medication abortion process needs to be done in person: The patient, provider and pharmacy can all interact virtually.

Mailed medication abortion is popular nationwide, particularly in states with abortion bans. Because of mailed medication abortion, the average number of abortions nationwide has actually increased since the U.S. Supreme Court in 2022 overturned Roe v. Wade, reversing abortion protections under the U.S. Constitution.

Providers in so-called “shield” states are a key reason for this. Eight U.S. states have laws that shield providers from civil, criminal and professional consequences for delivering reproductive health care to out-of-state patients.

In these shield states, doctors may prescribe abortion medication no matter where the patient lives, so long as that care is delivered by a provider licensed and located in the shield state, complying with the shield state’s laws.

These laws are the subject of legal conflicts between anti-abortion states and shield states.

Late in 2024, Texas sued a doctor in New York, a shield state, for violating Texas abortion and licensure laws. In early 2025, Louisiana indicted the same New York physician.

Texas won its case in a Texas court and then asked New York to enforce the judgment of more than $100,000 in fines and fees. A New York court has refused to do so, citing its shield law. New York also rejected Louisiana’s request to extradite the doctor to stand trial for the same reason.

On Dec. 4, 2025, Texas officially enacted the first bill in the country that explicitly targets shield laws. Passed in September 2025, HB 7 allows private citizens to file lawsuits against a person or entity for attempting or intending to mail abortion pills into the state.

Watch the courts and the FDA

Having written about shield laws extensively, I believe these interstate conflicts will land, sooner or later, before the Supreme Court. Right now, state and federal courts are deciding the issues.

If judges determine that shield laws are unconstitutional or that the FDA acted illegally, courts could substantially alter people’s ability to gain access to medication abortion.

So could the FDA. If it reimposes an unnecessary restriction on mifepristone, meaning the drug would no longer be widely available through telehealth, that decision would curb how 1 in 4 women in the U.S. receive abortion care today.

But opinion polls indicate that the majority of Americans do not think abortion should be illegal in all circumstances, and they vote accordingly.

In November 2025, Democrats won significant elections, for example, in New Jersey, Virginia and Pennsylvania. Abortion was absent from ballots in these states this year, but these races still held significance for abortion rights.

The election of a pro-choice governor and legislature in Virginia, for example, all but guarantees that abortion will continue to be legal in the last Southern state to protect broader abortion rights. Likewise, Pennsylvanians opted to keep the state supreme court’s liberal majority, which struck down the state prohibition on Medicaid payment for abortion.

In 2024, two years after the fall of Roe v. Wade, 14 states put forth ballot initiatives to enshrine abortion as a constitutional right. Eleven passed.

With little political support to pass a nationwide abortion ban, making it illegal to mail abortion pills is the most immediate way to obstruct reproductive health care in states with abortion bans.

The question for abortion in 2026, then, is: Will courts or federal forces do what democratic processes cannot?

This story was published in collaboration with Rewire News Group, a nonprofit newsroom dedicated to covering reproductive and sexual health.

The Conversation

Rachel Rebouché does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. 2026’s abortion battles will be fought more in courthouses and FDA offices than at the voting booth – https://theconversation.com/2026s-abortion-battles-will-be-fought-more-in-courthouses-and-fda-offices-than-at-the-voting-booth-269328

Encuentran en el asteroide Bennu claves inesperadas del origen de la vida

Source: The Conversation – (in Spanish) – By Claudia Martínez Sánchez, Biomedicine and Molecular Oncology Researcher, Universidad de Oviedo

Recreación de la sonda espacial OSIRIS-REx descendiendo hacia el asteroide Bennu para recolectar una muestra. NASA/Universidad de Arizona, CC BY

En 2023, una cápsula cayó suavemente en el desierto de Utah (Estados Unidos). Dentro viajaba algo más valioso que cualquier tesoro: polvo intacto de un asteroide llamado Bennu.

Tras meses de análisis, la comunidad científica ha confirmado un resultado sorprendente: en Bennu existen azúcares fundamentales como la ribosa y la glucosa. No son moléculas “dulces” sin más: la ribosa forma el esqueleto químico del ARN, una de las moléculas fundamentales para la vida, y la glucosa es una fuente universal de energía. Encontrarlas fuera de la Tierra es un descubrimiento sin precedentes.

Esto nos lleva a plantearnos que quizá la vida en la Tierra no empezó “desde cero”, sino con moléculas que ya existían antes, fabricadas en entornos extraterrestres como Bennu.

Un hallazgo distinto a todo lo anterior

Durante décadas se han identificado compuestos con relevancia biológica en meteoritos que han caído a la Tierra. Aminoácidos, bases nitrogenadas e incluso indicios de azúcares. Pero siempre existía una duda razonable: ¿estaban ahí desde el principio o aparecieron después? Un meteorito pasa por agua, aire, microbios e incluso por nuestras manos, procesos que pueden “contaminarlo”. Descifrar qué es terrestre y qué es extraterrestre es muy complicado.

Sin embargo, esta vez es diferente. El estudio publicado en la revista Nature Geoscience hace escasos días, demuestra que estos azúcares no vienen de la Tierra. Estaban en el asteroide mucho antes de que la cápsula tocara suelo. Las muestras fueron recogidas directamente en el espacio por la misión OSIRIS-REx, selladas al vacío, traídas a la Tierra y manipuladas en laboratorios que funcionan como quirófanos para material extraterrestre.

Un universo químicamente más fértil de lo que creíamos

Los azúcares de Bennu apuntan a una conclusión importante: la química necesaria para construir moléculas biológicas no es exclusiva de la Tierra. Puede surgir de forma natural en cuerpos pequeños, siempre que haya agua, minerales y algo de tiempo. Y Bennu tuvo todo eso.

El cuerpo original del que procede este asteroide albergó agua líquida en sus primeros millones de años. En ese entorno, moléculas simples pueden reorganizarse y transformarse en compuestos cada vez más complejos. No se necesita vida para producirlos: basta un entorno geológico activo.

Esto significa que mientras la Tierra era magma, ya existían en el sistema solar lugares donde se formaban moléculas que hoy asociamos a procesos biológicos. Moléculas que, millones de años después, podrían haber llegado a nuestro planeta en forma de meteoritos.

Ribosa sí, ADN no

Entre todos los azúcares detectados, la ribosa es la que más llama la atención. Es la base estructural del ARN, una molécula capaz de almacenar información o realizar algunas funciones similares a las de las proteínas. Antes de que existiera el ADN, el ARN pudo haber sostenido toda la química necesaria para los sistemas vivos más primitivos.

La ausencia de 2-desoxirribosa, el azúcar del ADN, es igual de interesante. Refuerza la idea de que el ADN no fue el protagonista en los primeros pasos de la vida, sino que apareció posteriormente.

Bennu aporta una pista inesperada: si la ribosa es relativamente estable y puede formarse en entornos extraterrestres, es razonable pensar que el ARN fue la primera molécula en sostener procesos propios de la vida en la Tierra primitiva. Lo que antes era solo una hipótesis teórica empieza ahora a apoyarse en observaciones directas.

¿Quiere decir esto que la vida se originó en el espacio?

No. Nadie ha encontrado vida en meteoritos ni en asteroides. Pero este descubrimiento sí fortalece una idea intermedia, más realista: la Tierra pudo recibir un aporte constante de moléculas complejas fabricadas en otros lugares.
Durante los primeros cientos de millones de años, nuestro planeta sufrió un intenso bombardeo de asteroides y cometas. Cada impacto podía liberar aminoácidos, bases nitrogenadas o azúcares formados en cuerpos como Bennu.

Estas moléculas no generan vida por sí mismas, pero hacen que el paso entre química simple y química compleja sea más sencillo. Reducen la distancia entre “casi vida” y “vida”.

No se trata de panspermia en su versión clásica –vida viajando de un planeta a otro–, sino de algo más modesto y más compatible con la evidencia: un impulso químico que aceleró los procesos que ya estaban ocurriendo en la Tierra.

Bennu como cápsula del tiempo

El momento de la aproximación de OSIRIS-REx al asteroide Bennu.
NASA, CC BY

La Tierra ha borrado casi todos los rastros de su infancia química: la tectónica, la erosión y la propia vida han reescrito continuamente su superficie. Pero Bennu, por el contrario, conserva materiales que no han cambiado desde los orígenes del sistema solar. Estudiarlo es lo más parecido que tenemos a viajar atrás en el tiempo y observar cómo era la química antes de que existieran océanos y continentes.

Por eso estas muestras son tan valiosas. Permiten comparar hipótesis, eliminar incertidumbres y entender mejor cuáles eran las condiciones reales en los primeros millones de años del sistema solar. No nos dan respuestas definitivas, pero sí un marco más claro desde el que pensar.

De regreso al cosmos

Más allá de los resultados científicos, hay algo profundamente humano en este descubrimiento. Nos invita a reconsiderar nuestro lugar en el universo. Nos recuerda que quizás no somos una excepción afortunada, sino parte de un proceso químico más amplio que lleva ocurriendo desde antes de la existencia del planeta que habitamos.

Cuando observamos las muestras de Bennu, no estamos mirando solo polvo antiguo. Estamos viendo un fragmento de una historia que la Tierra no pudo conservar. Y con él, la posibilidad de que el primer paso hacia la vida no ocurriera aquí, sino en algún pequeño cuerpo oscuro que viajó durante millones de años hasta caer en un lugar que, con el tiempo, se convertiría en nuestro hogar.

The Conversation

Claudia Martínez Sánchez no recibe salario, ni ejerce labores de consultoría, ni posee acciones, ni recibe financiación de ninguna compañía u organización que pueda obtener beneficio de este artículo, y ha declarado carecer de vínculos relevantes más allá del cargo académico citado.

ref. Encuentran en el asteroide Bennu claves inesperadas del origen de la vida – https://theconversation.com/encuentran-en-el-asteroide-bennu-claves-inesperadas-del-origen-de-la-vida-271691

New industry standards and tech advances make pre-owned electronics a viable holiday gift option

Source: The Conversation – USA (2) – By Suvrat Dhanorkar, Associate Professor of Operations Management, Georgia Institute of Technology

It’s easier than ever to repair or recycle electronic devices. Elisa Schu/picture alliance via Getty Images

Electronic gifts are very popular, and in recent years, retailers have been offering significant discounts on smartphones, e-readers and other electronics labeled as “pre-owned.” Research I have co-led finds that these pre-owned options are becoming increasingly viable, thanks in part to laws and policies that encourage recycling and reuse of devices that might previously have been thrown away.

Amazon, Walmart and Best Buy have dedicated pages on their websites for pre-owned devices. Manufacturers like Apple and Dell, as well as mobile service providers like AT&T and Verizon, offer their own options for customers to buy used items. Their sales rely on the availability of a large volume of used products, which are supplied by the emergence of an entire line of businesses that process used, discarded or returned electronics.

Those developments are some of the results of widespread innovations across the electronics industry that supply chain researcher Suresh Muthulingam and I have linked to California’s Electronic Waste Recycling Act, passed in 2003.

Recycling innovation

Originally intended to reduce the amount of electronic waste flowing into the state’s landfills, California’s law did far more, unleashing a wave of innovation, our analysis found.

We analyzed the patent-filing activity of hundreds of electronics firms over a 17-year time span from 1996 to 2012. We found that the passage of California’s law not only prompted electronics manufacturers to engage in sustainability-focused innovation, but it also sparked a surge in general innovation around products, processes and techniques.

Faced with new regulations, electronics manufacturers and suppliers didn’t just make small adjustments, such as tweaking their packaging to ensure compliance. They fundamentally rethought their design and manufacturing processes, to create products that use recycled materials and that are easily recyclable themselves.

For example, Samsung’s Galaxy S25 smartphone is a new product that, when released in May 2025, was made of eight different recycled materials, including aluminum, neodymium, steel, plastics and fiber.

Combined with advanced recycling technologies and processes, these materials can be recovered and reused several times in new devices and products. For example, Apple invented the Daisy Robot, which disassembles old iPhones in a matter of seconds and recovers a variety of precious metals, including copper and gold. These materials, which would otherwise have to be mined from rock, are reused in Apple’s manufacturing process for new iPhones and iPads.

How do consumers benefit?

In the past two decades, 25 U.S. states and Washington D.C. have passed laws requiring electronics recycling and refurbishing, the process of restoring a pre-owned electronic device so that it can function like new.

The establishment of industry guidelines and standards also means that all pre-owned devices are thoroughly tested for functionality and cosmetic appearance before resale.

Companies’ deeper engagement with innovation appears to have created organizational momentum that carried over into other areas of product development. For example, in our study, we found that the passage of California’s law directly resulted in a flurry of patents related to semiconductor materials, data storage and battery technology, among others. These scientific advances have made devices more durable, repairable and recyclable.

For the average consumer, the recycling laws and the resulting industry responses mean used electronics are available with similar reliability, warranties and return policies as new devices – and at prices as much as 50% lower.

The Conversation

Suvrat Dhanorkar does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. New industry standards and tech advances make pre-owned electronics a viable holiday gift option – https://theconversation.com/new-industry-standards-and-tech-advances-make-pre-owned-electronics-a-viable-holiday-gift-option-270347

From FIFA to the LA Clippers, carbon offset scandals are exposing the gap between sports teams’ green promises and reality

Source: The Conversation – USA (2) – By Brian P. McCullough, Associate Professor of Sport Management, University of Michigan

Under team owner Steve Ballmer, in the checkered shirt, the LA Clippers have cut their greenhouse gas emissions, but their carbon offsets raise questions. Ric Tapia/Icon Sportswire via Getty Images

If you go to a pro sports event today, there’s a good chance the stadium or arena will be powered at least in part by renewable energy. The team likely takes steps to reduce energy and waste. Some even claim to have net-zero greenhouse gas emissions, meaning any emissions they still do produce they offset by paying for projects, such as tree-planting, that reduce greenhouse gases elsewhere.

The venue upgrades have been impressive – Seattle’s hockey and basketball arena runs on 100% renewable energy, makes its rink ice from captured rainwater, and offers free public transit for ticket holders.

But how much of the teams’ offset purchases are actually doing the good that they claim?

It’s an important question, in part because fans may ultimately pay for those offsets.

A soccer player directs the ball with his head while leaping high into the air. The stands behind him are packed.
Lionel Messi of Argentina controls the ball during the FIFA World Cup Qatar 2022 final match. FIFA drew criticism for claiming the games were carbon neutral while relying heavily on sometimes questionable carbon offsets.
Julian Finney/Getty Images

The cost of carbon offsetting in sports varies by organization, with no industry standard for who pays. Some teams and leagues absorb costs through their operational budgets, treating carbon neutrality as a core responsibility. Others pass costs to consumers: Some teams add sustainability fees to ticket prices to offset each attendee’s carbon footprint. The payment model ultimately reflects whether an organization views offsetting as an institutional obligation or a shared responsibility with fans.

Carbon offsets in sports are also in the news, with scandals erupting around them in connection with sports from FIFA’s 2022 World Cup to basketball’s LA Clippers.

As sport management researchers, we have been following offset agreements and other sustainability commitments that teams and sports leagues such as FIFA have been making to see whether they translate into measurable environmental outcomes. We see lots of good intentions but also a disturbing amount of failures and outright fraud.

Where sports teams’ emissions come from

The vast majority of a sports team’s climate footprint comes from team’s and fans’ travel, which they have little control over. Leagues can reduce teams’ travel somewhat with creative scheduling, but unlike other industries, sports teams have few ways to reduce the bulk of their emissions.

What many of them do instead is offset those travel emissions by buying carbon credits.

Carbon credits are generated by projects that reduce greenhouse gases in the atmosphere or prevent greenhouse gas emissions. Many of those projects involve planting trees to remove carbon dioxide from the atmosphere; others expand clean energy to reduce fossil fuel use. Each carbon credit is supposed to represent the reduction or prevention of one metric ton of carbon dioxide.

However, carbon offset projects have come under scrutiny in recent years. Tree-planting projects, the most common type, take time to meet their promise as the trees grow, and wildfires and logging can wipe out the benefit. Studies have found that companies tend to buy cheap, low-quality carbon credits, which run a risk of exaggerating their carbon reduction claims or providing results that would have happened anyway, leaving no real climate benefit.

Unfortunately, several teams, perhaps unknowingly, have been purchasing fraudulent or low-quality credits.

Reputations at risk

FIFA brought the sports world’s carbon offset problem into the spotlight during the 2022 Qatar World Cup.

FIFA claimed the event would be carbon neutral, but that claim relied on creative accounting that understated the event’s construction and travel emissions. Organizers also used low-quality offsets. Many of those offsets were renewable energy projects with a high likelihood of being built anyway.

A year after the tournament, FIFA had completed offset purchases for less than a third of the World Cup’s estimated emissions, the nonprofit Carbon Market Watch found. And Switzerland’s advertising regulator ordered FIFA to stop claiming the World Cup had been “carbon neutral.”

A view across the stands during a game at Fenway Park under the lights.
In 2022, the Boston Red Sox announced a plan to route a portion of the proceeds from every ticket purchased at Fenway Park to a carbon offset project run by Aspiration. Aspiration later went bankrupt, and a ProPublica investigation found it had planted far fewer trees to store that carbon than promised.
Werner Kunz/Wikimedia Commons, CC BY-SA

The Clippers and baseball’s Boston Red Sox ran into problems when they publicly partnered with Aspiration, a now-bankrupt finance technology company and carbon credit broker, to meet their “carbon neutral” claims.

The Clippers had a US$300 million partnership with Aspiration that included paying the company at least $56 million for carbon credits in mid-2022, The New York Times reported. Both teams also had plans with Aspiration to offer fans a way to buy carbon credits to cover their own travel when purchasing tickets.

However, Aspiration officials claimed to have supported millions more tree-plantings than what had actually happened, a ProPublica investigation found. Aspiration co-founder Joe Sanberg pleaded guilty in 2025 to wire fraud involving false statements about financing to secure loans and attract investors, who lost at least $248 million.

The Aspiration partnership is also under investigation by the NBA over an endorsement deal the company made with Clippers all-star Kawhi Leonard at about the same time and questions about whether it was used to violate the league’s salary cap. Team owner Steve Ballmer, who personally invested at least $50 million in Aspiration, told ESPN he and the team did nothing wrong. “They conned me,” he said.

While the scandal focused on financial fraud and the salary cap, it also raised questions about the team’s sustainability claim.

Without verification, who knows?

In some cases, the value of offset projects is difficult to verify, even when trees are being planted nearby.

The Seattle Sounders FC declared itself the first carbon-neutral professional soccer team in North America in 2019 by cutting its waste, water and energy use and offsetting its remaining emissions through the nonprofit organization Forterra, which plants trees in the Puget Sound region.

While the effort positioned the club as a sustainability leader, the offsets lacked what’s known as third-party verification. Similar to how organic food must be certified by reputable agencies, third-party validation of carbon credits ensures credits truly represent the removal of carbon from the atmosphere or avoided emissions.

Without verification, it’s unclear whether claimed emission reductions are permanent, accurately tracked and transparently reported.

Potential legal consequences

Even the most prominent venues are susceptible to issues with unreliable credits.

Climate Pledge Arena in Seattle has been celebrated as the world’s first “zero-carbon” certified arena, with electric Zambonis, recycled materials, renewable energy and free public transit. It represents one of the most ambitious pushes to develop sustainable sport infrastructure globally.

A view from the upper deck of a large hockey arena. Two Zambonis are cleaning the ice.
Hockey rinks need energy to keep the ice frozen. Seattle’s Climate Pledge Arena has lowered its emissions with solar power from a local array and has even electried its Zambonis. But reports have raised questions about the quality of carbon offsets it purchased.
AP Photo/Maddy Grassy

To offset unavoidable construction emissions, the arena’s owner relied on carbon credits tied to projects meant to reduce rainforest loss in Colombia. However, an analysis by the carbon rating company Calyx Global found that while the arena’s credits may prevent some deforestation, the numbers likely overstate the benefits.

A 2023 report suggested that over 90% of rainforest carbon credits from the leading certifier of offsets lack evidence that they reduced deforestation. The certifier disputed that conclusion but is working to revise its review process.

When credits fail to offset real emissions, that erodes public trust and can expose organizations to potential legal consequences.

Delta Air Lines, for example, is facing a lawsuit over its carbon neutrality claim. The suit alleges that Delta misled passengers by describing itself as a “carbon-neutral airline” while relying on carbon offset projects that were ineffective or “junk.”

Time for some strategic reassessment

These and other failures in the carbon credit market suggest the industry needs to fundamentally reassess how sports teams achieve their climate goals.

To provide meaningful sustainability commitments, sports organizations and facilities can start at home by lowering their fossil fuel use and increasing their energy efficiency. Many arenas do this.

People walk under a canopy with solar panels above.
Fans walk under solar panels at NRG Stadium in Houston.
Tom Pennington/Getty Images

Leagues can design game schedules to reduce team and fan travel. Many of the Paris Olympics venues in 2022, for example, were connected by subway or bus. The 2026 FIFA World Cup, in contrast, has venues hundreds of miles apart across North America, meaning potentially higher emissions from fan travel.

Where offsets will still play a role, teams can ensure that they partner with verified carbon credit providers that deliver measurable, transparent carbon reductions.

In a field where public trust and reputation matter as much as performance, the sports industry cannot afford foul play on climate. We believe a shift toward strategies that cut emissions first, and then use only the most credible offsets, will be the difference between striking out and leading the sustainability game.

The Conversation

The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

ref. From FIFA to the LA Clippers, carbon offset scandals are exposing the gap between sports teams’ green promises and reality – https://theconversation.com/from-fifa-to-the-la-clippers-carbon-offset-scandals-are-exposing-the-gap-between-sports-teams-green-promises-and-reality-270428

Exposure to neighborhood violence leads some Denver teens to use tobacco and alcohol earlier, new study shows

Source: The Conversation – USA (3) – By Anna Maria Santiago, Professor of Community Development, Michigan State University

Denver teens who experience violence start using tobacco and alcohol earlier than their peers. BSIP/Getty Images

High levels of neighborhood violence increase the risk of Latino and African American teens in Denver starting to use alcohol and tobacco, according to our recent study.

In the U.S., approximately 2 in 10 adolescents between the ages of 12 and 20 drink alcohol. About 1 in 10 smoke cigarettes. For teens living in neighborhoods with high levels of disadvantage and social disorganization, the odds are 35% to 72% higher. Disadvantaged neighborhoods generally have higher levels of economic hardship, poorer educational opportunities and limited resources. Those factors weaken the social fabric of a community.

Although alcohol and tobacco use among adolescents has declined in recent years, both remain the most commonly used and abused substances compared to cocaine or heroin. Alcohol and tobacco use have been linked to substance dependence in adulthood, sexual victimization, some cancers and premature death.

One of us – Anna Maria Santiago – studies neighborhood effects, or how where children and adolescents live affects their health and well-being. Iris Margetis is a Ph.D. candidate in economics and co-author of the study.

Why it matters

Exposure to neighborhood violence has been thought to trigger adolescent alcohol and tobacco use as a way of coping with the heightened levels of stress associated with that exposure. However, previous findings have been mixed.

Seventeen percent of survey participants started smoking as teens. The average age of first use was 15.6 years. Fifteen percent started drinking as teens when they were 16.1 years old, on average.

Greater exposure to neighborhood violence prompted teens in our study to start drinking and smoking two to eight months earlier than their peers. Girls started using both substances earlier than boys. Latino teens started earlier than African Americans.

We controlled for other potential individual, household and neighborhood risk factors such as family size, household stressors and level of neighborhood disadvantage. The risk of starting to use alcohol still increased 32% for all teens residing in neighborhoods with greater violence. The risk of tobacco use in those neighborhoods was 1.3 to 1.5 times higher for boys, Latino and African American adolescents.

How we do our work

We analyzed administrative and survey data originally gathered from a natural experiment involving a policy change in Denver for approximately 1,100 Latino and African American teens. The teens lived in 110 census tracts across metro Denver.

To measure exposure to violence, we used our survey data to create a neighborhood problems index that measured several factors. Those included the presence of people selling drugs, gang activity, homes broken into by burglars, people being robbed or mugged, people getting beaten or raped, and children and youth getting into trouble. We defined the presence of three or more of these as high exposure to neighborhood violence.

What still isn’t known

We still don’t know what community interventions work best. But research suggests that caregiver and community-level action is crucial. According to study participants, caregivers monitored their adolescents closely. They limited unsupervised time outside or with friends, especially in neighborhoods with higher exposure to violence.

Study findings suggest that neighborhood youth clubs, sports teams, community centers and parks may serve as powerful deterrents to substance use initiation among teens. Community-led, evidence-based programs such as Rise Above Colorado support efforts promoting positive youth development and fostering positive community norms as prevention and early intervention strategies.

The state of Colorado says preventing or delaying initiation of both alcohol and tobacco use remain key public health goals.

However, additional work is needed to develop programming and activities that facilitate these efforts in Latino and African American communities.

The Research Brief is a short take on interesting academic work.

The Conversation

Anna Maria Santiago previously received funding from the U.S. Department of Housing and Urban Development; the National Institute of Child Health and Human Development; the John D. and Catherine T. MacArthur Foundation; the Ford Foundation; the Annie E Casey Foundation and the W.K. Kellogg Foundation.

Iris Margetis does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. Exposure to neighborhood violence leads some Denver teens to use tobacco and alcohol earlier, new study shows – https://theconversation.com/exposure-to-neighborhood-violence-leads-some-denver-teens-to-use-tobacco-and-alcohol-earlier-new-study-shows-270412

Doulas play essential roles in reproductive health care – and more states are beginning to recognize it

Source: The Conversation – USA (3) – By Adetola F. Louis-Jacques, Clinical Assistant Professor of Obstetrics and Gynecology, University of Florida

Research shows that doulas improve birth experiences and outcomes. Antonio_Diaz/iStock via Getty Images Plus

A growing share of Americans, especially in rural areas, are losing access to reproductive health care. At the same time, American women are dying during or after pregnancy at higher rates than in any other high-income country.

As a result, many U.S. health care providers and policymakers are looking for ways to improve maternal care.

We believe doulas – care workers who provide nonmedical support before and during pregnancy, labor, birth and the postpartum period – may be a part of the solution.

We are a physician-researcher specializing in high-risk pregnancies and breastfeeding and a Ph.D. candidate in sociology focused on reproductive health and health care disparities.

As hospitals adopt more favorable policies and states expand insurance coverage for doula services, doulas are becoming part of the mainstream U.S. maternal health system.

But there are still significant barriers to access, including awareness, costs and challenges to full partnership with doulas in hospitals.

What a doula offers

Pregnancy, birth and the postpartum period are vulnerable times, and many parents-to-be and new parents find it can be difficult to navigate. Doulas advocate for their clients, helping them voice what they need. They can also help address mistreatment and guide them to appropriate resources.

Doulas do not perform clinical tasks, such as giving medical advice, making medical decisions, providing prescriptions or delivering babies. Rather, they provide nonmedical support. This will look different depending on the type of doula parents hire.

Fertility doulas assist people who are trying to get pregnant. They offer emotional support throughout the fertility journey, complementing the medical care, diagnostics and interventions provided by fertility doctors.

During pregnancy and labor, birth doulas help their clients identify normal symptoms and those that may be urgent warning signs. They also provide labor support, such as positioning and breathing assistance, massage, words of encouragement, coaching, education, continuous presence and other forms of comfort. They offer direct emotional support through the validation of clients’ experiences and emotions.

Postpartum doulas offer extended support to new parents and infants in the immediate days, weeks or months after delivery. They educate parents and act as a bridge to mental health services and additional resources such as diapers, feeding support and housing needs. They may help with supporting a new mom’s infant feeding goals, integrating the infant into the family, sibling care and processing their births.

Full-spectrum doulas offer support throughout pregnancy, delivery and up to six months after birth. Still others offer bereavement services for parents experiencing pregnancy loss, such as abortion, miscarriage and stillbirth.

This sort of holistic care can be invaluable, even for women with access to good medical care. Several months ago, one of us (Adetola) helped a patient find a postpartum doula. She was an educated woman with insurance and access to top medical care. She was suffering the effects of postpartum depression and anxiety despite all the therapy and medical resources offered.

She later wrote that, for her, “the support of my postpartum doula was invaluable in my recovery. My doula provided me with the support I needed in caring for my baby for me to care for myself. Not only did she care for my baby for me to rest, but she helped me with breastfeeding.”

A woman kneels in front of another woman breastfeeding a baby
During the postpartum period, doulas support new mothers in feeding their newborns.
Igor Alecsander/iStock via Getty Images Plus

Doula training

As of August 2025, there were 2,232 registered doula businesses in the U.S. California has the highest concentration at 7.5%, while West Virginia has the lowest concentration, 0.1%. These numbers may not reflect hospital-based or nonprofit-affiliated doulas, or those not formally registered.

In the U.S., more than 100 independent organizations provide doula training. Some of the larger organizations include DONA International, Childbirth International and the Childbirth and Postpartum Professional Association. Doula training typically covers communication and advocacy skills, stages of labor and birth, and postpartum support. It also includes coursework on how to build a business as well as infection prevention and control.

Some organizations provide online or in-person courses, and doula training can also be done through apprenticeships. While certifications or licenses are not required to practice, various state Medicaid programs mandate training and certification to qualify for Medicaid reimbursement.

Better outcomes with doula support

The services that doulas offer can complement the more mainstream biomedical approach of many doctors and nurses.

Maternal health outcomes in the U.S. have been worsening for decades in comparison to other high-income countries.

But studies show that a doula-clinician partnership improves key components of maternal health care, such as better communication and patient-centered care, accountability in the health care team and continuity of support for mothers.

Having a doula present in the lead-up to delivery, at the delivery or both is associated with lower rates of cesarean deliveries and preterm births and fewer low-birthweight infants.

Doula support is also associated with improved childbirth education attendance, birth satisfaction, self-efficacy and confidence, breastfeeding experiences and outcomes, and positive infant-care behaviors.

After birth, infants born with a doula present have higher five-minute Apgar scores, an assessment of infant health taken exactly five minutes after birth. Parents who received doula support have reduced rates of postpartum depression and anxiety.

Doula support has also been shown to help close maternal outcome gaps, particularly those rooted in racial, socioeconomic and institutional barriers.

And beyond all the health benefits for parents and infants, research shows that doulas can reduce health care costs associated with having a baby.

Some hospitals provide doulas to all of their pregnant and postpartum patients.

Funding sources for doula support

Unfortunately, despite all of these benefits, many U.S. families struggle to afford doula care. Private insurance does not typically cover doula services. Clients can pay out of pocket using a flat-rate service charge, fee-for-service or monthly stipend model. They can also pay for these services using extended benefits such as flex or health savings accounts.

The cost varies by state and region, experience level and service package. Out-of-pocket costs for comprehensive birth doula services can range from US$800 to more than $3,000 across the U.S.

As of September 2025, 23 states plus Washington, D.C., were actively reimbursing Medicaid coverage for doula care.

Only two states – Rhode Island and Louisiana – currently require that private health plans cover doula care. However, Colorado, Virginia, Illinois and Delaware are in the process of implementing doula coverage in private health plans. More states are expected to continue efforts to require doula coverage for private health plans.

Some community-based organizations and nonprofits provide free or low-cost doula care through grants or donations. These programs usually prioritize low-income families. In New York City, free or low-cost doula support is available through the Citywide Doula Initiative which serves Medicaid-eligible families, teen parents and residents of priority neighborhoods.

Moreover, some hospitals and birth centers employ doulas or work with them as part of their maternal care teams.

Finding a doula

When hiring a doula, you’ll want to consider their training, certifications and experience. You will also want to know how available they are, what services they offer and their fees and payment methods.

In addition:

  • Consider asking your health care provider or hospital for recommendations for doulas in the community.
  • Look into doula directories, such as DONA International, DoulaMatch.net, CAPPA and the National Black Doulas Association. Also, check to see whether your state has a doula directory, like those in California, Minnesota Oregon and Michigan.
  • Ask for recommendations from friends, family or local parenting groups.
  • Check local community boards, birth centers and drugstores for any doula advertisements.
  • You might also connect with doulas at birth or parenting classes.

The Conversation

Adetola F. Louis-Jacques receives funding from NIH, Direct Relief, Children’s Trust of Alachua County.

Seun Mauton Ajoseh does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

ref. Doulas play essential roles in reproductive health care – and more states are beginning to recognize it – https://theconversation.com/doulas-play-essential-roles-in-reproductive-health-care-and-more-states-are-beginning-to-recognize-it-253903

What started as a war of words between China and Japan is fuelling real tension in the Asia-Pacific region

Source: The Conversation – Canada – By Kuan-Wei Chen, Researcher, Air and Space Law, McGill University; Bond University

In a now deleted social media post, the Consul General of the People’s Republic of China to the Japanese city of Osaka recently threatened to “cut off” Japanese Prime Minister Sanae Takaichi’s “filthy head.”

This graphic threat was in response to Takaichi’s suggestion that Japan’s Self-Defense Forces may exercise the right of collective self-defence and become involved in the event of a Chinese attack on Taiwan.

China has called on Takaichi to retract her “erroneous remarks.”

The Chinese outrage is apparently intensifying after Chinese military planes were accused of locking their radar on Japanese fighter jets near the Okinawa islands. China also imposed a ban on Japanese seafood imports.

China’s response has political and nationalistic undertones. China views Taiwan as an “inalienable part” of its territory, a reminder of the “century of humiliation” when the [island was ceded by Imperial China to Japan and became a Japanese colony in 1895].

A matter of history — and law

Even after the Second World War ended, sovereignty over Taiwan was never formally settled. China believes Taiwan must be “reunified” with the motherland, if necessary by force.

The number and intensity of Chinese military drills aimed at intimidating Taiwan have significantly increased in recent years. Chinese leader Xi Jinping has reportedly begun mobilizing the People’s Liberation Army for an invasion of Taiwan by 2027.

Taiwan’s status is complicated under international law. While it has a functioning government, population and defined territory — all necessary elements of statehood — much of the world does not officially recognize Taiwan as a state.

Most countries, including Canada and the United States, engage with Taiwan in a non-official capacity and simply “acknowledge” China’s insistence that Taiwan is part of China.

This respect paid to China is a matter of geopolitics and strategic ambiguity likely due to China’s global economic and political clout, and has little foundation in law.

International resolutions, declarations

China often asserts the 1943 Cairo Declaration as the legal basis for its claim over Taiwan. However, this unsigned media communiqué lacks legal force under international law, something pointed out by British Prime Minister Winston Churchill in 1955.

At the outbreak of the Korean War, U.S. President Harry Truman stated unequivocally that the “determination of the future status of (Taiwan) must await the restoration of security in the Pacific, a peace settlement with Japan or consideration by the United Nations.”

The 1951 Treaty of San Francisco, which ended the war between Japan and the Allied powers, is a legally binding treaty. While Japan renounced “all right, title and claim” to Taiwan, there was no mention of the People’s Republic of China — established only two years earlier — in terms of Taiwanese sovereignty.

The United Nations has never considered, let alone decided upon, the issue of sovereignty over Taiwan. China often cites the UN’s General Assembly Resolution 2758 in 1971 as another legal basis for its assertion of sovereignty over Taiwan. But that resolution only addresses the status of the People’s Republic of China as the legitimate representative of China and makes no mention of Taiwan.

The European Parliament and the parliaments of Australia, the Netherlands, as well as U.S. congress, have openly opposed China’s distortion of the UN resolution and attempts to exert undue influence over international organizations for political ends.

Japan-Taiwan proximity

Takaichi’s remarks are simply a reiteration of the late Japanese Prime Minister Shinzo Abe’s remarks that “a Taiwan emergency is a Japan emergency (台湾有事は日本有事).”

This is no surprise since, at their closest point, Japan and Taiwan are just over 100 kilometres apart. Japan’s deployment of anti-air missiles on the Okinawa prefecture’s Yonaguni Island and long-range anti-ship missiles at the mouth of the Miyako Strait are clearly aimed at countering a potential Chinese offensive.

The site of the largest American Air Force base in East Asia just a 90-minute flight from Taiwan, and is similarly already gearing up for a potential Chinese missile attack amid rising tensions.




Read more:
Why a row over military bases on Okinawa spells trouble for US-Japan relations


Taiwan itself is situated at the crossroads of vital maritime and aviation routes, and manufactures more than 70 per cent of the world’s microchips.

If China opts to blockade or attack Taiwan, it will severely impact the world economy since a fifth of global maritime trade, valued at $2.5 trillion, transits through the Taiwan Strait.

It’s in no one but China’s interests if the Chinese mount an attack, and certainly it’s not the will of the 23 million inhabitants of the independent island nation who enjoy some of the highest levels of political and civil liberties in the world.

The U.S. continues to bolster Taiwan’s defence to deter a Chinese attack since Taiwan’s security is pivotal to America’s strategic standing in the Asia-Pacific region and the world.

Global peace and security

With great power comes great responsibility, and this is true for all states. Threats of invasion, the use of force and non-peaceful means of settling disputes are all prohibited under international law. Undiplomatic rhetoric and distortions of history and the law is also detrimental to peace.

If Taiwan truly is a part of China, then there would be no need for an invasion or threats to “crush” any foreign interference. Through its wolf-warrior diplomacy and shows of force, China is in effect globalizing the Taiwan issue.

As the recent G7 statement states, the international community has “an interest in the preservation of peace and stability across the Taiwan Strait” as China’s military drills and threats of war jeopardize “global security and prosperity.”

In a world beset by conflict in the Middle East and an enduring war in Ukraine, tensions are again heating up in East Asia. Will cooler heads prevail?

The Conversation

Kuan-Wei Chen is the recipient of a Australian Government Research Training Program scholarship.

ref. What started as a war of words between China and Japan is fuelling real tension in the Asia-Pacific region – https://theconversation.com/what-started-as-a-war-of-words-between-china-and-japan-is-fuelling-real-tension-in-the-asia-pacific-region-270434