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Effect of combination treatment with glp-1 receptor agonists and sglt-2 inhibitors on incidence of cardiovascular and serious renal events, prenatal opioid exposure and risk of neuropsychiatric disorders in children, temporal trends in lifetime risks of atrial fibrillation and its complications, antipsychotic use in people with dementia, predicting the risks of kidney failure and death in adults with moderate to severe chronic kidney disease, impact of large scale, multicomponent intervention to reduce proton pump inhibitor overuse, esketamine after childbirth for mothers with prenatal depression, glucagon-like peptide 1 receptor agonist use and risk of thyroid cancer, use of progestogens and the risk of intracranial meningioma, delirium and incident dementia in hospital patients, derivation and external validation of a simple risk score for predicting severe acute kidney injury after intravenous cisplatin, quality and safety of artificial intelligence generated health information, large language models and the generation of health disinformation, 25 year trends in cancer incidence and mortality among adults in the uk, cervical pessary versus vaginal progesterone in women with a singleton pregnancy, comparison of prior authorization across insurers, diagnostic accuracy of magnetically guided capsule endoscopy with a detachable string for detecting oesophagogastric varices in adults with cirrhosis, ultra-processed food exposure and adverse health outcomes, added benefit and revenues of oncology drugs approved by the ema, exposure to air pollution and hospital admission for cardiovascular diseases, short term exposure to low level ambient fine particulate matter and natural cause, cardiovascular, and respiratory morbidity, optimal timing of influenza vaccination in young children, effect of exercise for depression, association of non-alcoholic fatty liver disease with cardiovascular disease and all cause death in patients with type 2 diabetes, duration of cpr and outcomes for adults with in-hospital cardiac arrest, clinical effectiveness of an online physical and mental health rehabilitation programme for post-covid-19 condition, atypia detected during breast screening and subsequent development of cancer, publishers’ and journals’ instructions to authors on use of generative ai in academic and scientific publishing, effectiveness of glp-1 receptor agonists on glycaemic control, body weight, and lipid profile for type 2 diabetes, neurological development in children born moderately or late preterm, invasive breast cancer and breast cancer death after non-screen detected ductal carcinoma in situ, all cause and cause specific mortality in obsessive-compulsive disorder, acute rehabilitation following traumatic anterior shoulder dislocation, perinatal depression and risk of mortality, undisclosed financial conflicts of interest in dsm-5-tr, effect of risk mitigation guidance opioid and stimulant dispensations on mortality and acute care visits, update to living systematic review on sars-cov-2 positivity in offspring and timing of mother-to-child transmission, perinatal depression and its health impact, christmas 2023: common healthcare related instruments subjected to magnetic attraction study, using autoregressive integrated moving average models for time series analysis of observational data, demand for morning after pill following new year holiday, christmas 2023: christmas recipes from the great british bake off, effect of a doctor working during the festive period on population health: experiment using doctor who episodes, christmas 2023: analysis of barbie medical and science career dolls, christmas 2023: effect of chair placement on physicians’ behavior and patients’ satisfaction, management of chronic pain secondary to temporomandibular disorders, christmas 2023: projecting complete redaction of clinical trial protocols, christmas 2023: a drug target for erectile dysfunction to help improve fertility, sexual activity, and wellbeing, christmas 2023: efficacy of cola ingestion for oesophageal food bolus impaction, conservative management versus laparoscopic cholecystectomy in adults with gallstone disease, social media use and health risk behaviours in young people, untreated cervical intraepithelial neoplasia grade 2 and cervical cancer, air pollution deaths attributable to fossil fuels, implementation of a high sensitivity cardiac troponin i assay and risk of myocardial infarction or death at five years, covid-19 vaccine effectiveness against post-covid-19 condition, association between patient-surgeon gender concordance and mortality after surgery, intravascular imaging guided versus coronary angiography guided percutaneous coronary intervention, treatment of lower urinary tract symptoms in men in primary care using a conservative intervention, autism intervention meta-analysis of early childhood studies, effectiveness of the live zoster vaccine during the 10 years following vaccination, effects of a multimodal intervention in primary care to reduce second line antibiotic prescriptions for urinary tract infections in women, pyrotinib versus placebo in combination with trastuzumab and docetaxel in patients with her2 positive metastatic breast cancer, association of dcis size and margin status with risk of developing breast cancer post-treatment, racial differences in low value care among older patients in the us, pharmaceutical industry payments and delivery of low value cancer drugs, rosuvastatin versus atorvastatin in adults with coronary artery disease, clinical effectiveness of septoplasty versus medical management for nasal airways obstruction, ultrasound guided lavage with corticosteroid injection versus sham lavage with and without corticosteroid injection for calcific tendinopathy of shoulder, early versus delayed antihypertensive treatment in patients with acute ischaemic stroke, mortality risks associated with floods in 761 communities worldwide, interactive effects of ambient fine particulate matter and ozone on daily mortality in 372 cities, association between changes in carbohydrate intake and long term weight changes, future-case control crossover analysis for adjusting bias in case crossover studies, association between recently raised anticholinergic burden and risk of acute cardiovascular events, suboptimal gestational weight gain and neonatal outcomes in low and middle income countries: individual participant data meta-analysis, efficacy and safety of an inactivated virus-particle vaccine for sars-cov-2, effect of invitation letter in language of origin on screening attendance: randomised controlled trial in breastscreen norway, visits by nurse practitioners and physician assistants in the usa, non-erosive gastro-oesophageal reflux disease and oesophageal adenocarcinoma, venous thromboembolism with use of hormonal contraception and nsaids, food additive emulsifiers and risk of cardiovascular disease, balancing risks and benefits of cannabis use, promoting activity, independence, and stability in early dementia and mild cognitive impairment, effect of home cook interventions for salt reduction in china, cancer mortality after low dose exposure to ionising radiation, effect of a smartphone intervention among university students with unhealthy alcohol use, long term risk of death and readmission after hospital admission with covid-19 among older adults, mortality rates among patients successfully treated for hepatitis c, association between antenatal corticosteroids and risk of serious infection in children, the proportions of term or late preterm births after exposure to early antenatal corticosteroids, and outcomes, safety of ba.4-5 or ba.1 bivalent mrna booster vaccines, comparative effectiveness of booster vaccines among adults aged ≥50 years, third dose vaccine schedules against severe covid-19 during omicron predominance in nordic countries, private equity ownership and impacts on health outcomes, costs, and quality, healthcare disruption due to covid-19 and avoidable hospital admission, educational inequalities in mortality and their mediators among generations across four decades, prevalence and predictors of data and code sharing in the medical and health sciences, medicare eligibility and in-hospital treatment patterns and health outcomes for patients with trauma, therapeutic value of first versus supplemental indications of drugs in us and europe, follow us on, content links.

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1 Cite Share Alanyl-tRNA synthetase, AARS1, is a lactate sensor and lactyltransferase that lactylates p53 and contributes to tumorigenesis. Zong Z, Xie F, Wang S, Wu X, Zhang Z, Yang B, Zhou F. Zong Z, et al. Cell. 2024 Apr 17:S0092-8674(24)00397-0. doi: 10.1016/j.cell.2024.04.002. Online ahead of print. Cell. 2024. PMID: 38653238 Cite Share Item in Clipboard

2 Cite Share Efficacy and safety of eco-friendly inhalers: focus on combination ipratropium bromide and albuterol in chronic obstructive pulmonary disease. Panos RJ. Panos RJ. Int J Chron Obstruct Pulmon Dis. 2013;8:221-30. doi: 10.2147/COPD.S31246. Epub 2013 Apr 30. Int J Chron Obstruct Pulmon Dis. 2013. PMID: 23658481 Free PMC article. Review. Cite Share Item in Clipboard

3 Cite Share Labour promotes systemic mobilisation of monocytes, T cell activation and local secretion of chemotactic factors in the intervillous space of the placenta. Vikberg S, Lindau R, Solders M, Raffetseder J, Budhwar S, Ernerudh J, Tiblad E, Kaipe H. Vikberg S, et al. Front Immunol. 2023 Mar 8;14:1129261. doi: 10.3389/fimmu.2023.1129261. eCollection 2023. Front Immunol. 2023. PMID: 36969250 Free PMC article. Cite Share Item in Clipboard

4 Cite Share Global incidence, prevalence, years lived with disability (YLDs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries in 204 countries and territories and 811 subnational locations, 1990-2021: a systematic analysis for the Global Burden of Disease Study 2021. GBD 2021 Diseases and Injuries Collaborators. GBD 2021 Diseases and Injuries Collaborators. Lancet. 2024 Apr 15:S0140-6736(24)00757-8. doi: 10.1016/S0140-6736(24)00757-8. Online ahead of print. Lancet. 2024. PMID: 38642570 Free article. Cite Share Item in Clipboard

5 Cite Share Sequential CD7 CAR T-Cell Therapy and Allogeneic HSCT without GVHD Prophylaxis. Hu Y, Zhang M, Yang T, Mo Z, Wei G, Jing R, Zhao H, Chen R, Zu C, Gu T, Xiao P, Hong R, Feng J, Fu S, Kong D, Xu H, Cui J, Huang S, Liang B, Yuan X, Cui Q, Guo H, Yu Y, Feng Y, Jin C, Ren J, Chang AH, Wang D, Huang H. Hu Y, et al. N Engl J Med. 2024 Apr 25;390(16):1467-1480. doi: 10.1056/NEJMoa2313812. N Engl J Med. 2024. PMID: 38657244 Cite Share Item in Clipboard

6 Cite Share Vitamin D regulates microbiome-dependent cancer immunity. Giampazolias E, Pereira da Costa M, Lam KC, Lim KHJ, Cardoso A, Piot C, Chakravarty P, Blasche S, Patel S, Biram A, Castro-Dopico T, Buck MD, Rodrigues RR, Poulsen GJ, Palma-Duran SA, Rogers NC, Koufaki MA, Minutti CM, Wang P, Vdovin A, Frederico B, Childs E, Lee S, Simpson B, Iseppon A, Omenetti S, Kelly G, Goldstone R, Nye E, Suárez-Bonnet A, Priestnall SL, MacRae JI, Zelenay S, Patil KR, Litchfield K, Lee JC, Jess T, Goldszmid RS, Reis E Sousa C. Giampazolias E, et al. Science. 2024 Apr 26;384(6694):428-437. doi: 10.1126/science.adh7954. Epub 2024 Apr 25. Science. 2024. PMID: 38662827 Cite Share Item in Clipboard

7 Cite Share IGSF8 is an innate immune checkpoint and cancer immunotherapy target. Li Y, Wu X, Sheng C, Liu H, Liu H, Tang Y, Liu C, Ding Q, Xie B, Xiao X, Zheng R, Yu Q, Guo Z, Ma J, Wang J, Gao J, Tian M, Wang W, Zhou J, Jiang L, Gu M, Shi S, Paull M, Yang G, Yang W, Landau S, Bao X, Hu X, Liu XS, Xiao T. Li Y, et al. Cell. 2024 Apr 18:S0092-8674(24)00355-6. doi: 10.1016/j.cell.2024.03.039. Online ahead of print. Cell. 2024. PMID: 38657602 Cite Share Item in Clipboard

8 Cite Share Microglial lipid droplet accumulation in tauopathy brain is regulated by neuronal AMPK. Li Y, Munoz-Mayorga D, Nie Y, Kang N, Tao Y, Lagerwall J, Pernaci C, Curtin G, Coufal NG, Mertens J, Shi L, Chen X. Li Y, et al. Cell Metab. 2024 Apr 16:S1550-4131(24)00118-9. doi: 10.1016/j.cmet.2024.03.014. Online ahead of print. Cell Metab. 2024. PMID: 38657612 Cite Share Item in Clipboard

9 Cite Share Transient loss of Polycomb components induces an epigenetic cancer fate. Parreno V, Loubiere V, Schuettengruber B, Fritsch L, Rawal CC, Erokhin M, Győrffy B, Normanno D, Di Stefano M, Moreaux J, Butova NL, Chiolo I, Chetverina D, Martinez AM, Cavalli G. Parreno V, et al. Nature. 2024 Apr 24. doi: 10.1038/s41586-024-07328-w. Online ahead of print. Nature. 2024. PMID: 38658752 Cite Share Item in Clipboard

10 Cite Share Gut symbionts alleviate MASH through a secondary bile acid biosynthetic pathway. Nie Q, Luo X, Wang K, Ding Y, Jia S, Zhao Q, Li M, Zhang J, Zhuo Y, Lin J, Guo C, Zhang Z, Liu H, Zeng G, You J, Sun L, Lu H, Ma M, Jia Y, Zheng MH, Pang Y, Qiao J, Jiang C. Nie Q, et al. Cell. 2024 Apr 17:S0092-8674(24)00350-7. doi: 10.1016/j.cell.2024.03.034. Online ahead of print. Cell. 2024. PMID: 38653239 Cite Share Item in Clipboard

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• 26 Mar 2024
• Research & Ideas

How Humans Outshine AI in Adapting to Change

Could artificial intelligence systems eventually perform surgeries or fly planes? First, AI will have to learn to navigate shifting conditions as well as people do. Julian De Freitas and colleagues pit humans against machines in a video game to study AI's current limits and mine insights for the real world.

• 12 Mar 2024

Publish or Perish: What the Research Says About Productivity in Academia

Universities tend to evaluate professors based on their research output, but does that measure reflect the realities of higher ed? A study of 4,300 professors by Kyle Myers, Karim Lakhani, and colleagues probes the time demands, risk appetite, and compensation of faculty.

• 24 Jan 2024

Why Boeing’s Problems with the 737 MAX Began More Than 25 Years Ago

Aggressive cost cutting and rocky leadership changes have eroded the culture at Boeing, a company once admired for its engineering rigor, says Bill George. What will it take to repair the reputational damage wrought by years of crises involving its 737 MAX?

• 19 Sep 2023

What Chandrayaan-3 Says About India's Entrepreneurial Approach to Space

India reached an unexplored part of the moon despite its limited R&D funding compared with NASA and SpaceX. Tarun Khanna discusses the significance of the landing, and the country's advancements in data and digital technology.

• 28 Mar 2023

The FDA’s Speedy Drug Approvals Are Safe: A Win-Win for Patients and Pharma Innovation

Expediting so-called breakthrough therapies has saved millions of dollars in research time without compromising drug safety or efficacy, says research by Ariel Stern, Amitabh Chandra, and colleagues. Could policymakers harness the approach to bring life-saving treatments to the market faster?

• 16 Mar 2023

Why Business Travel Still Matters in a Zoom World

Meeting in person can make all the difference for colleagues from different time zones or cultural backgrounds. A study by Prithwiraj Choudhury traces flight patterns among 5,000 airports around the world to show how business travel propels innovation.

• 13 Apr 2021
• Working Paper Summaries

Population Interference in Panel Experiments

In panel experiments, units are exposed to different interventions over time. This article introduces a unifying framework for studying panel experiments with population interference, in which a treatment assigned to one experimental unit affects another experimental unit's outcome. Findings have implications for fields as diverse as education, economics, and public health.

• 22 Feb 2021

Private and Social Returns to R&D: Drug Development and Demographics

Research and development (R&D) by pharmaceutical firms focuses disproportionately on medical conditions afflicting the elderly. The proportion of R&D spending targeting older age groups is increasing over time. Even though these investments in R&D prolong life expectancy and improve quality of life, they have little effect on measured productivity and output growth.

• 15 Dec 2020

Designing, Not Checking, for Policy Robustness: An Example with Optimal Taxation

The approach used by most economists to check academic research results is flawed for policymaking and evaluation. The authors propose an alternative method for designing economic policy analyses that might be applied to a wide range of economic policies.

• 30 Nov 2020

Short-Termism, Shareholder Payouts, and Investment in the EU

Shareholder-driven “short-termism,” as evidenced by increasing payouts to shareholders, is said to impede long-term investment in EU public firms. But a deep dive into the data reveals a different story.

• 22 Oct 2020

Estimating Causal Effects in the Presence of Partial Interference Using Multivariate Bayesian Structural Time Series Models

A case study of an Italian supermarket introducing a new pricing policy—in which it reduced prices on some brands—offers managers a new approach to reduce uncertainty. The approach is flexible and can be applied to different business problems.

• 06 Oct 2020

Design and Analysis of Switchback Experiments

This paper presents a framework for managers to design and run switchback experiments.

• 28 Sep 2020

What Can Economics Say About Alzheimer's Disease?

This essay discusses the role of market frictions and "missing medicines" in drug innovation and highlights how frameworks and toolkits of economists can help our understanding of the determinants and effects of Alzheimer's disease on health.

• 24 Aug 2020

When Do Experts Listen to Other Experts? The Role of Negative Information in Expert Evaluations for Novel Projects

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• 10 Aug 2020

COVID's Surprising Toll on Careers of Women Scientists

Women scientists and those with young children are paying a steep career price in the pandemic, according to new research by Karim Lakhani, Kyle Myers, and colleagues. Open for comment; 0 Comments.

• 02 Aug 2020
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Is the 'Experimentation Organization' Becoming the Competitive Gold Standard?

SUMMING UP: Digital experimentation is gaining momentum as an everyday habit in many organizations, especially those in high tech, say James Heskett's readers. Open for comment; 0 Comments.

• 27 Jul 2020

Gender Inequality in Research Productivity During the COVID-19 Pandemic

Analysis of data from the largest open-access repositories for social science in the world finds that female researchers’ productivity significantly dropped relative to that of male researchers as a result of the lockdown in the United States.

• 08 Jul 2020

Inventing the Endless Frontier: The Effects of the World War II Research Effort on Post-War Innovation

Investments made in World War II by the United States Office of Scientific Research and Development powered decades of subsequent innovation and the take-off of regional technology hubs around the country.

• 06 Apr 2020

A General Theory of Identification

Statistical inference teaches us how to learn from data, whereas identification analysis explains what we can learn from it. This paper proposes a simple unifying theory of identification, encouraging practitioners to spend more time thinking about what they can estimate from the data and assumptions before trying to estimate it.

• 23 Mar 2020

The Effects of Hierarchy on Learning and Performance in Business Experimentation

Do senior managers help or hurt business experiments? Analyzing a dataset of more than 6,300 experiments on the A/B/n testing platform Optimizely, this study suggests that involving senior executives in experimentation teams can have surprising consequences.

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Researchers detect a new molecule in space

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New research from the group of MIT Professor Brett McGuire has revealed the presence of a previously unknown molecule in space. The team's open-access paper, “ Rotational Spectrum and First Interstellar Detection of 2-Methoxyethanol Using ALMA Observations of NGC 6334I ,” appears in April 12 issue of The Astrophysical Journal Letters .

Zachary T.P. Fried , a graduate student in the McGuire group and the lead author of the publication, worked to assemble a puzzle comprised of pieces collected from across the globe, extending beyond MIT to France, Florida, Virginia, and Copenhagen, to achieve this exciting discovery. 

“Our group tries to understand what molecules are present in regions of space where stars and solar systems will eventually take shape,” explains Fried. “This allows us to piece together how chemistry evolves alongside the process of star and planet formation. We do this by looking at the rotational spectra of molecules, the unique patterns of light they give off as they tumble end-over-end in space. These patterns are fingerprints (barcodes) for molecules. To detect new molecules in space, we first must have an idea of what molecule we want to look for, then we can record its spectrum in the lab here on Earth, and then finally we look for that spectrum in space using telescopes.”

Searching for molecules in space

The McGuire Group has recently begun to utilize machine learning to suggest good target molecules to search for. In 2023, one of these machine learning models suggested the researchers target a molecule known as 2-methoxyethanol. 

“There are a number of 'methoxy' molecules in space, like dimethyl ether, methoxymethanol, ethyl methyl ether, and methyl formate, but 2-methoxyethanol would be the largest and most complex ever seen,” says Fried. To detect this molecule using radiotelescope observations, the group first needed to measure and analyze its rotational spectrum on Earth. The researchers combined experiments from the University of Lille (Lille, France), the New College of Florida (Sarasota, Florida), and the McGuire lab at MIT to measure this spectrum over a broadband region of frequencies ranging from the microwave to sub-millimeter wave regimes (approximately 8 to 500 gigahertz). 

The data gleaned from these measurements permitted a search for the molecule using Atacama Large Millimeter/submillimeter Array (ALMA) observations toward two separate star-forming regions: NGC 6334I and IRAS 16293-2422B. Members of the McGuire group analyzed these telescope observations alongside researchers at the National Radio Astronomy Observatory (Charlottesville, Virginia) and the University of Copenhagen, Denmark. 

“Ultimately, we observed 25 rotational lines of 2-methoxyethanol that lined up with the molecular signal observed toward NGC 6334I (the barcode matched!), thus resulting in a secure detection of 2-methoxyethanol in this source,” says Fried. “This allowed us to then derive physical parameters of the molecule toward NGC 6334I, such as its abundance and excitation temperature. It also enabled an investigation of the possible chemical formation pathways from known interstellar precursors.”

Looking forward

Molecular discoveries like this one help the researchers to better understand the development of molecular complexity in space during the star formation process. 2-methoxyethanol, which contains 13 atoms, is quite large for interstellar standards — as of 2021, only six species larger than 13 atoms were detected outside the solar system , many by McGuire’s group, and all of them existing as ringed structures.  

“Continued observations of large molecules and subsequent derivations of their abundances allows us to advance our knowledge of how efficiently large molecules can form and by which specific reactions they may be produced,” says Fried. “Additionally, since we detected this molecule in NGC 6334I but not in IRAS 16293-2422B, we were presented with a unique opportunity to look into how the differing physical conditions of these two sources may be affecting the chemistry that can occur.”

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Helping women get better sleep by calming the relentless 'to-do lists' in their heads

Yuki Noguchi

Katie Krimitsos is among the majority of American women who have trouble getting healthy sleep, according to a new Gallup survey. Krimitsos launched a podcast called Sleep Meditation for Women to offer some help. Natalie Champa Jennings/Natalie Jennings, courtesy of Katie Krimitsos hide caption

Katie Krimitsos is among the majority of American women who have trouble getting healthy sleep, according to a new Gallup survey. Krimitsos launched a podcast called Sleep Meditation for Women to offer some help.

When Katie Krimitsos lies awake watching sleepless hours tick by, it's almost always because her mind is wrestling with a mental checklist of things she has to do. In high school, that was made up of homework, tests or a big upcoming sports game.

"I would be wide awake, just my brain completely spinning in chaos until two in the morning," says Krimitsos.

There were periods in adulthood, too, when sleep wouldn't come easily, like when she started a podcasting company in Tampa, or nursed her first daughter eight years ago. "I was already very used to the grainy eyes," she says.

Now 43, Krimitsos says in recent years she found that mounting worries brought those sleepless spells more often. Her mind would spin through "a million, gazillion" details of running a company and a family: paying the electric bill, making dinner and dentist appointments, monitoring the pets' food supply or her parents' health checkups. This checklist never, ever shrank, despite her best efforts, and perpetually chased away her sleep.

"So we feel like there are these enormous boulders that we are carrying on our shoulders that we walk into the bedroom with," she says. "And that's what we're laying down with."

By "we," Krimitsos means herself and the many other women she talks to or works with who complain of fatigue.

Women are one of the most sleep-troubled demographics, according to a recent Gallup survey that found sleep patterns of Americans deteriorating rapidly over the past decade.

"When you look in particular at adult women under the age of 50, that's the group where we're seeing the most steep movement in terms of their rate of sleeping less or feeling less satisfied with their sleep and also their rate of stress," says Gallup senior researcher Sarah Fioroni.

Overall, Americans' sleep is at an all time low, in terms of both quantity and quality.

A majority – 57% – now say they could use more sleep, which is a big jump from a decade ago. It's an acceleration of an ongoing trend, according to the survey. In 1942, 59% of Americans said that they slept 8 hours or more; today, that applies to only 26% of Americans. One in five people, also an all-time high, now sleep fewer than 5 hours a day.

Popular myths about sleep, debunked

"If you have poor sleep, then it's all things bad," says Gina Marie Mathew, a post-doctoral sleep researcher at Stony Brook Medicine in New York. The Gallup survey did not cite reasons for the rapid decline, but Mathew says her research shows that smartphones keep us — and especially teenagers — up later.

She says sleep, as well as diet and exercise, is considered one of the three pillars of health. Yet American culture devalues rest.

"In terms of structural and policy change, we need to recognize that a lot of these systems that are in place are not conducive to women in particular getting enough sleep or getting the sleep that they need," she says, arguing things like paid family leave and flexible work hours might help women sleep more, and better.

No one person can change a culture that discourages sleep. But when faced with her own sleeplessness, Tampa mom Katie Krimitsos started a podcast called Sleep Meditation for Women , a soothing series of episodes in which she acknowledges and tries to calm the stresses typical of many women.

Shots - Health News

Many grouchy, error-prone workers just need more sleep.

That podcast alone averages about a million unique listeners a month, and is one of 20 podcasts produced by Krimitsos's firm, Women's Meditation Network.

"Seven of those 20 podcasts are dedicated to sleep in some way, and they make up for 50% of my listenership," Krimitsos notes. "So yeah, it's the biggest pain point."

Krimitsos says she thinks women bear the burdens of a pace of life that keeps accelerating. "Our interpretation of how fast life should be and what we should 'accomplish' or have or do has exponentially increased," she says.

She only started sleeping better, she says, when she deliberately cut back on activities and commitments, both for herself and her two kids. "I feel more satisfied at the end of the day. I feel more fulfilled and I feel more willing to allow things that are not complete to let go."

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Research: Why People Really Buy Upcycled Products

• Sara Caprioli,
• Christoph Fuchs,
• Bram Van den Bergh

Creativity is more of a selling point than sustainability.

Researchers who analyzed consumer feedback from Etsy discovered that what consumers value most about upcycled products is not their sustainability but their creativity. Their findings offer some guidelines for companies who hope to design and successfully market upcycled products: 1) Designers should consider using components from other industries to enhance the appeal of their products and encourage cross-industry collaboration; 2) Product designers and managers should identify new uses for product components; 3) Marketers should emphasize creativity, as well as sustainability, in their messaging about upcycled products; and 4) Companies can boost the appeal of new products by emphasizing design elements that remind consumers of upcycled products.

Upcycling — the creation of new products by reusing one or more components from ones — is having a moment.

• SC Sara Caprioli is a postdoctoral researcher at the TUM School of Management in Germany. Her work focuses on the effects of creativity and artificial intelligence on human behavior.
• CF Christoph Fuchs is a professor of marketing at the University of Vienna in Austria. His research is situated at the interface of marketing, technology, and human behavior.
• BB Bram Van den Bergh is professor of marketing at the Rotterdam School of Management, Erasmus University Rotterdam. His research focuses on decision making and persuasion.

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Yellowstone’s Wolves: A Debate Over Their Role in the Park’s Ecosystem

New research questions the long-held theory that reintroduction of such a predator caused a trophic cascade, spawning renewal of vegetation and spurring biodiversity.

Yellowstone’s ecological transformation through the reintroduction of wolves has become a case study for how to correct out-of-balance ecosystems. But new research challenges that notion. Credit... Elizabeth Boehm/Danita Delimont, via Alamy

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By Jim Robbins

• April 23, 2024

In 1995, 14 wolves were delivered by truck and sled to the heart of Yellowstone National Park in Wyoming, where the animal had long been absent. Others followed.

Since then, a story has grown up, based on early research, that as the wolves increased in number, they hunted the park’s elk herds, significantly reducing them by about half from 17,000.

The wolves’ return and predatory dominance was believed to have had a widespread effect known as a trophic cascade, by decreasing grazing and restoring and expanding forests, grasses and other wildlife. It supposedly even changed the course of rivers as streamside vegetation returned.

Yellowstone’s dramatic transformation through the reintroduction of wolves has become a global parable for how to correct out-of-balance ecosystems.

In recent years, however, new research has walked that story back. Yes, stands of aspen and willows are thriving again — in some places. But decades of damage from elk herds’ grazing and trampling so thoroughly changed the landscape that large areas remain scarred and may not recover for a long time, if ever.

Wolf packs, in other words, are not magic bullets for restoring ecosystems.

“I would say it’s exaggerated, greatly exaggerated,” said Thomas Hobbs, a professor of natural resource ecology at Colorado State University and the lead author of a long-term study that adds new fuel to the debate over whether Yellowstone experienced a trophic cascade.

“You could argue a trophic trickle maybe,” said Daniel Stahler, the park’s lead wolf biologist who has studied the phenomenon. “Not a trophic cascade.”

Not only is the park’s recovery far less robust than first thought, but the story as it has been told is more complex, Dr. Hobbs said.

But the legend of the wolves’ influence on the park persists.

“How in the world does this lovely story — and it is a beautiful story — come to be seen as fact?” Dr. Hobbs wondered. A chapter of a book tried to answer that, concluding that a video called “ How Wolves Change Rivers ,” which has received tens of millions of views, contributed mightily to the tale.

The ecological record is complicated by the fact that, as elk declined, the number of bison increased substantially, continuing some of the same patterns, like heavy grazing in some places. Moreover, Yellowstone is growing warmer and drier with climate change.

Large numbers of elk in the north of the park had caused significant ecological changes — vegetation disappeared, trampled streams led to extensive erosion, and invasive plant species took hold. Riparian vegetation, or the grasses, the trees and the shrubs along riverbanks and streams, provides a critical habitat for birds, insects and other species to flourish and to maintain biodiversity in the park.

Once elk numbers dwindled, willows and aspens returned along rivers and streams and flourished. The beaver, an engineer of ecosystems, reappeared, using the dense new growth of willows for both food and construction materials. Colonies built new dams, creating ponds that enhanced stream habitats for birds, fish, grizzlies and other bears as well as promoting the growth of more willows and spring vegetation.

But wolves were only one piece of a larger picture, argue Dr. Hobbs and other skeptics of a full-blown trophic cascade at Yellowstone. Grizzly bears and humans played a role, too. For eight years after wolves re-entered the park, hunters killed more elk than the wolves did.

“The other members of the predator guild increased, and human harvest outside of the park has been clearly shown to be responsible for the decline in elk numbers the first 10 years after the wolves were introduced,” Dr. Hobbs said.

The changes attributed to the presence of stalking wolves, some research showed, weren’t only the result of fewer elk, but of a change in elk behavior called “the ecology of fear.” Scientists suggested that the big ungulates could no longer safely hang out along river or stream banks and eat everything in sight. They became extremely cautious, hiding in places where they could be vigilant. That allowed a return of vegetation in those places.

Dr. Hobbs and others contend that subsequent research has not borne that theory out.

Another overlooked factor is that around the same time wolves were returning, 129 beavers were reintroduced by the U.S. Forest Service onto streams north of the park. So it wasn’t just wolf predation on elk and the subsequent return of wolves that enabled an increase in beavers, experts say.

Some researchers say the so-called trophic cascade and rebirth of streamside ecosystems would have been far more robust if it weren’t for the park’s growing bison herd. The bison population is at an all-time high — the most recent count last summer found nearly 5,000 animals. Much larger than elk, bison are less likely to be vulnerable to wolves, which numbered 124 this winter.

The park’s bison, some researchers say, are overgrazing and otherwise seriously damaging the ecosystems — allowing the spread of invasive species and trampling and destroying native plants.

The heavily grazed landscape is why, critics say, some 4,000 bison, also a record, left Yellowstone for Montana in the winter of 2023-24, when an unusually heavy snow buried forage. Because some bison harbor a disease, called brucellosis, that state officials say could infect cattle, they are not welcome outside the park’s borders. (There are no documented cases of transmission between bison and cattle.)

Montana officials say killing animals that may carry disease as they leave the park is the only way to stem the flow. During a hunt that began in the winter of 2023, Native Americans from tribes around the region took part. All told, hunters killed about 1,085 bison; 88 more were shipped to slaughter and 282 were transferred to tribes. This year, just a few animals have left the park.

The Park Service is expected to release a bison management plan in the coming months. It is considering three options: to allow for 3,500 to 5,000 animals, 3,500 to 6,000, or a more natural population that could reach 7,000.

Richard Keigley, who was a research ecologist for the federal Geological Survey in the 1990s, has become an outspoken critic of the park’s bison management.

“They have created this juggernaut where we’ve got thousands of bison and the public believes this is the way things always were,” he said. “The bison that are there now have destroyed and degraded their primary ranges. People have to realize there’s something wrong in Yellowstone.”

Dr. Keigley said the bison population in the park fluctuated in the early years of the park, with about 229 animals in 1967. It has grown steadily since and peaked last year at 5,900.

“There is a hyperabundant bison population in our first national park,” said Robert Beschta, a professor emeritus of forest ecosystems at Oregon State University who has studied Yellowstone riparian areas for 20 years. He pointed to deteriorating conditions along the Lamar River from bison overgrazing.

“They are hammering it,” Mr. Beschta said. “The Lamar ranks right up there with the worst cattle allotments I’ve seen in the American West. Willows can’t grow. Cottonwoods can’t grow.”

A warmer and drier climate, he said, is making matters worse.

Such opinions, however, are not settled science. Some park experts believe that the presence of thousands of bison enhances park habitats because of something called the Green Wave Hypothesis.

Chris Geremia, a park biologist, is an author of a paper that makes the case that a large numbers of bison can stimulate plant growth by grazing grasses to the length of a suburban lawn. “By creating these grazing lawns bison and other herbivores — grasshoppers, elk — these lawns are sustaining more nutritious food for these animals,” he said.

Dr. Geremia contends that a tiny portion — perhaps one-tenth of one percent — of the park may be devoid of some plants. “The other 99.9 percent of those habitats exists in all different levels of willow, aspen and cottonwood,” he said.

The Greater Yellowstone Coalition, a conservation organization, favors a bison population of 4,000 to 6,000 animals. Shana Drimal, who heads the group’s bison conservation program, said that park officials needed to monitor closely changing conditions like climate, drought and bison movement to ensure the ecosystems wouldn’t become further degraded.

Several scientists propose allowing the bison to migrate to the buffer zones beyond the park’s borders, where they are naturally inclined to travel. But it remains controversial because of the threat of disease.

“The only solution is to provide suitable winter range outside the park where they should be tolerated,” said Robert Crabtree, a chief scientist for the Yellowstone Ecological Research Center, a nonprofit. “When they migrate outside the park now it’s to habitat they evolved to prefer — and instead we kill them and ship them away.”

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The AI-fueled stock market bubble will crash in 2026, research firm says

• The AI-fueled stock market bubble will burst in 2026, according to Capital Economics.
• The research firm said rising interest rates and higher inflation will weigh down equity valuations.
• "We suspect that the bubble will ultimately burst beyond the end of next year, causing a correction in valuations."

An artificial intelligence-fueled stock market bubble will burst in 2026, according to Capital Economics.

The research firm has said that a stock market bubble, driven by investor excitement towards artificial intelligence, would drive the S&P 500 to as high as 6,500 by 2025, led by technology stocks.

But starting in 2026, those stock market gains should unwind precipitously as higher interest rates and an elevated inflation rate start to weigh down equity valuations.

"Ultimately, we anticipate that returns from equities over the next decade will be poorer than over the previous one. And we think that the long-running outperformance of the US stock market may come to an end," Capital Economics' Diana Iovanel and James Reilly said.

Their bearish stock market call is somewhat counter-intuitive, as the economists expect the growing adoption of AI will spark a boost in economic growth driven by increases in productivity. That economic boost should result in higher inflation than most expect and, in tandem, higher interest rates.

Higher interest rates and inflation are ultimately bad news for stock prices, as evidenced by the recent stock market decline , which was sparked by a surprisingly hot March CPI inflation report.

"We suspect that the bubble will ultimately burst beyond the end of next year, causing a correction in valuations. After all, this dynamic played out around both the dot-com bubble of the late 1990s and early 2000s and the Great Crash of 1929," Iovanel and Reilly said. 

The expected bursting of the stock market bubble should lead to a decade of investment returns that favor bonds over stocks. 

"We expect stronger returns as government bond yields settle at higher levels," Capital Economics said of the fixed-income market. 

Capital Economics forecasts that between now and the end of 2033, US stocks will deliver average annual returns of just 4.3%, which is well below the long-term average return of about 7% after inflation. Meanwhile, Capital Economics said it expects US Treasurys will return 4.5% in the same period, slightly edging out equity gains. 

Those projected returns are in stark contrast to the average annual returns of 13.1% delivered by US stocks over the past decade.

"American exceptionalism may end in the coming years," Iovanel and Reilly said.

But there is one major risk to their outlook, according to the analysts, and that's the inherent difficulty of accurately timing the top of a stock market bubble, and how long the unwinding of the bubble might last.

"When and how the AI-fueled equity bubble bursts is a key risk to our forecast. In particular, one downside risk is that the aftermath of the bursting of the bubble lasts longer than one year, as was the case following the dot com bubble," Iovanel and Reilly said.

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Breaking ice, and helicopter drops: winning photos of working scientists

Nature ’s annual photography competition attracted stunning images from around the world, including two very different shots featuring the polarstern research vessel..

By Jack Leeming

23 April 2024

This article is also available as a pdf version .

Scientists often take images from their work – whether they produce medical scans, microscopic captures, or computer screenshots of tricky pieces of code during the course of their work. By continuing our Working Scientist photography competition, we aim to celebrate and highlight the very best images created by our audience in the pursuit of research.

We received more than 200 entries this year from researchers working around the world. The winner and the four runners-up were selected by a jury of Nature staff, including three of the journal’s picture editors. All will receive a prize of £500 (US$620), in the form of Amazon vouchers or a donation to charity, as well as a year’s subscription to Nature .

This image, taken on top of the icebreaker research vessel Polarstern , shows the delicate process of retrieving an instrument called a CTD (short for conductivity, temperature, depth) that had become trapped under sea ice off the coast of northeastern Greenland.

CTDs, which are anchored to the sea floor, measure how ocean properties such as salinity and temperature vary with depth. At some point, the sea ice had closed over the top of this one, forcing the Polarstern to skirt carefully around the equipment, breaking the ice to rescue it from the freezing ocean.

Credit: Richard Jones

“You’re crashing into ice and breaking through it. So it wasn’t particularly calm sailing for the majority of the trip,” remembers Richard Jones, who took the image in September 2017 and is the winner of Nature ’s 2024 Working Scientist photography competition. His research aims to improve estimates of the rate at which ice is being lost from the world’s glacial ice sheets.

Jones, a glaciologist at Monash University in Melbourne, Australia, highlights the photographic contrast between icebreaker and ice that he’d become used to in his five weeks aboard the Polarstern . “All you really see is blue and white. And sometimes that might feel pretty monotonous, but the colours from the CTD instrument and the orange of the crane contrast the scene and also complement it quite nicely.”

Here are the rest of the winning images from the competition.

Credit: Ryan Wagner

Reaching the beak

Conservation biologist Ryan Wagner snapped this photo of field biologist Sonia Vallocchia feeding a recently caught kiwikiu ( Pseudonestor xanthophrys ), in January this year. It was taken on Haleakalā volcano on the Hawaiian island of Maui. Wagner, a PhD student at Washington State University Vancouver, was on an expedition to the island as a science communicator, hoping to raise awareness of the plight of the endangered birds.

“Only 130 of these birds remain on Earth,” explains Wagner. “Their numbers have crashed due to avian malaria, which is spread by invasive mosquitoes. As climate change warms the island, mosquitoes have advanced upslope into the high-elevation refuges where native birds survive. A single mosquito bite can kill a kiwikiu.”

He hopes that ornithologists such as Vallocchia, who works for the Maui Forest Birds Recovery Project in Makawao, will help to save these birds by bringing some of them (by helicopter) to the Maui Bird Conservation Center, also in Makawao. There, they will be treated for malaria and join a captive breeding programme, he says.

Credit: Luiz L. Saldanha/Kimberly P. Castro

Library of leaves

PhD student Kim Castro took this photo of her colleague, postdoctoral researcher Luiz Leonardo Saldanha, in a herbarium that they both work in regularly. It’s shared between the University of Zurich and the Swiss Federal Institute of Technology (ETH) in Zurich. Both Castro and Saldanha investigate the medicinal plants of the Amazon at the Department of Systematic and Evolutionary Botany at the University of Zurich, although the two have very different approaches: whereas Saldanha investigates their chemical diversity, Castro looks at how the plants are perceived by Indigenous communities in the Amazon, specializing in how the plants smell.

A herbarium, Saldanha says, is “like a library — but instead of books, there are plants here”. Saldanha posed with this particular sample ( Palicourea corymbifera , collected in 1977) because it comes from his home country, Brazil, but is used by the Indigenous Desano people in Colombia as a medicinal herb. “So it creates a commonality between South American countries,” he says.

Credit: Herton Escobar/University of São Paulo Images

Mountain drop-off

In this dramatic image, taken from below the still-spinning, deafening blades of a military helicopter, scientists shelter with their equipment after being dropped off at the top of a remote mountain in northern Amazonia. They are taking part in a biodiversity-research expedition to Serra Imeri, an isolated mountain range that rises through the forest canopy near the border of Brazil and Venezuela, in November 2022.

“A total of 14 scientists and dozens of military support personnel took part in the expedition, which lasted for 11 days and resulted in the discovery of several new species of amphibians, reptiles, birds and plants,” says photographer Herton Escobar, a science journalist who works with the scientists pictured, at the University of São Paulo in Brazil.

Credit: Emiliano Cimoli

Go with the floe

Emiliano Cimoli, a remote-sensing scientist at the Institute for Marine and Antarctic Studies at the University of Tasmania, Australia, took the second photograph featuring the research vessel Polarstern in this year’s collection of winning images. Here, Carolin Mehlmann and Thomas Richter, mathematicians at the University of Magdeburg, Germany, are measuring the depth of snow across a giant ice floe drifting in the middle of the Arctic Ocean.

The image was taken during a two-month voyage organized by the Alfred Wegener Institute, based in Bremerhaven, Germany, in August 2023. The goal of the expedition was to evaluate interactions between the ice physics, biology, hydrography, biogeochemistry and biodiversity of the Arctic ecosystem, from the sea ice to the sea floor.

Nature 628 , 919-921 (2024)

doi: https://doi.org/10.1038/d41586-024-01181-7

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