Life-threatening childbirth complications among Medicaid enrollees vary widely by state and race-ethnicity

Threefold difference between lowest rate of severe maternal morbidity in Utah compared to highest in D.C.; causes differ

Peer-Reviewed Publication

MICHIGAN MEDICINE - UNIVERSITY OF MICHIGAN

The risk of life-threatening maternal complications from childbirth may be higher depending on where you live, a new study finds.

For Medicaid enrollees in Utah, the rate of “near miss” instances that could have led to the death of a birthing person during pregnancy or delivery was the lowest in the U.S., occurring among 80 per 10,000 live births.

Meanwhile, on the other side of the country in Washington D.C., the rate of such cases was nearly three times higher – 210 per 10,000 deliveries.

The drivers for these unexpected maternal outcomes, referred to as severe maternal morbidity, also varied by race and ethnicity, according to the research in Obstetrics & Gynecology, or The Green Journal.

“Our findings suggest wide variation in rates and potential causes of severe maternal morbidity by state, and by race and ethnicity across and within states,” said lead author Lindsay Admon, M.D., M.Sc., an assistant professor of obstetrics and gynecology at the University of Michigan Medical School and obstetrician-gynecologist at U-M Health Von Voigtlander Women’s Hospital.

“This data highlights states that have the greatest burden of severe maternal complications and may help guide and tailor interventions aimed at reducing morbidity among those at highest risk.”

Researchers analyzed national data from 4.8 million live births among Medicaid enrollees (average age of 27) between 2016 and 2018, tracking unanticipated outcomes resulting in significant short- or long-term health consequences within six weeks of delivery.

Overall, 146 out of every 10,000 live births among Medicaid enrollees in the U.S. involved serious complications, according to the study.

Differences in maternal morbidity rates across states and by race and ethnicity

The new findings come on the heels of alarming data from the Centers for Disease Control and Prevention finding a sharp rise in maternal deaths during the pandemic.

Medicaid finances slightly more than two in five births in the U.S. and a disproportionate number of births to individuals with the greatest risk of experiencing severe maternal complications and death, including Black and Indigenous populations, rural residents, and those living in lower income ZIP codes.

More than two thirds of individuals with live births in the study were eligible for Medicaid for income while a smaller proportion qualified due to pregnancy. 

“Medicaid enrollees are at the highest risk of maternal morbidity and mortality,” Admon said.

“Many states are pursuing clinical interventions and health policies designed to address maternal health inequities through Medicaid programs. But until now, we haven’t had a big picture view of health outcomes on a geographic and demographic level to inform these decisions.”

The five states with the highest rates of severe maternal morbidity included D.C., California, Nevada, New Jersey, and New York. Meanwhile, rates for Utah, Maryland, Rhode Island, Nebraska, and New Hampshire fell in the bottom tenth percentile.

But state-by-state outcomes differed depending on a person’s racial or ethnic group.  Among deliveries to non-Hispanic Black individuals, the three states with the highest rates of severe maternal morbidity were Alaska, New York, and New Jersey while states with the lowest rates were in New Mexico, North Dakota, and Utah.

For white individuals, California, West Virginia, and South Carolina ranked highest for severe adverse maternal health outcomes while the lowest rates were found in Utah, North Dakota and Maine.

Drivers of maternal morbidity

The leading factor linked with severe maternal morbidity among all Medicaid enrollees was eclampsia, a rare but life-threatening complication from high blood pressure during pregnancy that can cause seizures. But conditions varied across states and by race and ethnicity within states.

In Texas, for example, eclampsia was the top driver of potentially fatal maternal outcomes overall among people covered by Medicaid. However, non-Hispanic Black Texans experienced acute heart failure as the leading driver, and white Texans experienced sepsis as the leading driver of maternal health outcomes.

“Previous research suggests that pre-existing chronic conditions like obesity, diabetes, and mental health conditions are linked to greater risk for adverse maternal health outcomes,” Admon said.

“We need to focus on interventions that improve the overall health of our reproductive-aged population and identify clinical, societal, and structural barriers that may prevent individuals from achieving optimal health before pregnancy.”

Since maternal mortality is a relatively rare event, Admon adds, studying severe maternal morbidity to understand “near miss” events that could have resulted in an in-hospital maternal death may help efforts to mitigate the most adverse maternal health outcomes.

“When we look at maternal health across populations within states, we can see that some communities are performing much better than others with respect to life-threatening labor and delivery outcomes,” Admon said.

“This added nuance will be helpful to clinicians, policymakers and advocacy groups who are committed to strategies to improve maternal health across the country.”

 

---

JOURNAL

Obstetrics and Gynecology

NIH-funded study finds doxycycline reduces sexually transmitted infections by two-thirds

Peer-Reviewed Publication

NIH/NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES

 

IMAGE: SCANNED ELECTRON MICROGRAPH IMAGE OF NEISSERIA GONORRHOEAE BACTERIA, WHICH CAN CAUSE GONORRHEA. view more 

CREDIT: NIAID

The oral antibiotic doxycycline prevented the acquisition of sexually transmitted infections (STIs) when tested among men who have sex with men (MSM) and transgender women who took the medication within 72 hours of having condomless sex, according to findings published today in the New England Journal of Medicine. Specifically, the post-exposure approach, termed doxy-PEP, resulted in a two-thirds reduction in the incidence of syphilis, gonorrhea, and chlamydia among the study participants, all of whom reported having an STI within the previous year. However, the research also revealed a slight increase in antibacterial resistance that requires further exploration, the authors found. The research was funded by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. 

“Effective methods for preventing sexually transmitted infections are badly needed,” said Hugh Auchincloss, M.D., NIAID acting director. “This is an encouraging finding that could help reduce the number of sexually transmitted infections in populations most at-risk.” 

STI incidence has been increasing in the United States over the past few years with a disproportionate impact among MSM and transgender women. An estimated 2.5 million cases of syphilis, gonorrhea, and chlamydia occurred in 2021 up from 2.4 million cases in 2020, according to the Centers for Disease Control and Prevention. If left untreated, STIs can lead to serious health consequences, including brain and nerve problems, blindness, infertility and increased risk of HIV acquisition. Antimicrobial resistance among STIs is an emerging public health threat, particularly with Neisseria gonorrhoeae, and threatens available treatment options.

The study was led by researchers at the University of California at San Francisco (UCSF) and the University of Washington, Seattle. It enrolled 501 adults at four clinic sites in San Francisco and Seattle who were at least 18 years of age; assigned male sex at birth; reported sexual activity with a man in the previous year; diagnosed with HIV or taking or planning to take pre-exposure prophylaxis (PrEP) medication to prevent HIV acquisition; and diagnosed with gonorrhea, chlamydia or early syphilis in the prior year. Of those enrolled, 327 participants were taking HIV PrEP medications, and 174 participants were people living with HIV. 

Participants were randomly assigned to receive either doxy-PEP or standard of care. Those in the doxy-PEP arm were instructed to take one 200 milligram (mg) doxycycline-delayed release tablet, ideally within 24 hours but no later than 72 hours after condomless sex. Doxycycline is a broad-spectrum antibiotic in a family called tetracyclines. Participants were assessed by study staff every three months for adherence and side effects to the medication regimen and tested for STIs. Participant acceptability of the medication was assessed at six-and-12-month clinic visits. An independent data and safety monitoring board reviewed study progress and safety and effectiveness data every six months. 

Among participants on HIV PrEP, at least one or more STIs were diagnosed in 10.7% of quarterly clinic visits in the doxy-PEP study arm compared to 31.9% of visits in the standard of care arm. Among study participants living with HIV, one or more STIs were diagnosed in 11.8% of quarterly visits in the doxy-PEP arm versus 30.5% in the standard of care arm. Gonorrhea was the most frequently diagnosed STI in the study. Participants reported good adherence to the medication regimen with 86.2% reporting taking doxy-PEP consistently within 72 hours of condomless sex, and 71.3% reported never missing a dose. No safety or acceptability issues were identified in the study.

“Given its demonstrated efficacy in several trials, doxy-PEP should be considered as part of a sexual health package for men who have sex with men and transwomen if they have an increased risk of STIs,” according to Annie Luetkemeyer, M.D., professor of infectious diseases at Zuckerberg San Francisco General Hospital at UCSF, and co-principal investigator of the study. “It will be important to monitor the impact of doxy-PEP on antimicrobial resistance patterns over time and weigh this against the demonstrated benefit of reduced STIs and associated decreased antibiotic use for STI treatment in men at elevated risk for recurrent STIs.” 

In examining the potential for antimicrobial resistance during doxy-PEP use, the researchers discovered tetracycline resistance in a greater number of incident gonorrhea strains among those in the doxy-PEP arm than among those in the standard of care group (38.5% versus 12.5%, respectively). This suggests that doxy-PEP may offer less protection against gonorrhea strains that are already tetracycline-resistant and that wider population-based surveillance for this type of resistance is important. Additionally, the researchers found that doxy-PEP reduced Staphylococcus aureus—a bacteria commonly found on the skin “colonization”—by 50% after a year. However, in those who still had Staphylococcus aureus colonization at month 12, a modestly higher proportion of those in the doxy-PEP group had doxycycline resistance (16% vs 8%). This is important because doxycycline may be used to treat methicillin-resistant Staphylococcus aureus skin and soft tissue infections. Additional research and longer follow-up periods are needed to examine the potential antimicrobial resistance effect of intermittent doxy-PEP use. Doxy-PEP use in other populations disproportionately impacted by STIs, including women with HIV and those taking HIV PrEP, deserves further exploration as well. 

“We need new, effective STI prevention methods and three studies have now demonstrated that doxy-PEP significantly reduces gonorrhea, chlamydia and syphilis. In the next several years during the implementation of doxy-PEP, we need to learn about maximizing equitable access and impact,” said Dr. Connie Celum, Professor of Global Health and Medicine at the University of Washington and co-principal investigator of the DoxyPEP Study. 

Reference: AF Leutkemeyer et al. Doxycycline to prevent bacterial sexually transmitted infections. NEJM DOI: 10.1056/NEJMoa2211934 (2023).

---

NIAID conducts and supports research—at NIH, throughout the United States, and worldwide—to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID website. 

About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit https://www.nih.gov/. 

NIH...Turning Discovery Into Health®

---

JOURNAL

New England Journal of Medicine

DOI

10.1056/NEJMoa2211934 

ACCELERATIONISM

Birch reduction simplified to a one-minute mechanochemical process

Peer-Reviewed Publication

HOKKAIDO UNIVERSITY

 

IMAGE: BALL MILLING JAR AND REAGENTS USED IN THE SIMPLIFIED MECHANOCHEMICAL BIRCH REDUCTION. (PHOTO: KOJI KUBOTA) view more 

CREDIT: KOJI KUBOTA

The traditionally cumbersome yet widely-used Birch reduction can now be carried out in a mere minute in air using an optimized mechanochemical approach.

The Birch reduction is a reaction commonly used to make medicines and bioactive compounds, but the laborious process typically requires that chemists handle liquid ammonia, use cryogenic temperatures, and carry out time-consuming steps. Researchers at the Institute for Chemical Reaction Design and Discovery (WPI-ICReDD) in Hokkaido University have developed a simplified method for performing the Birch reduction that avoids the use of ammonia, can be done at room temperature and in ambient air, and is 20-150 times faster than conventional methods.

A number of lithium-based methods for performing the Birch reduction in solution have been previously developed, but since lithium reacts with both air and water, these processes still required complicated reaction setups with an inert atmosphere or dehydrated conditions.  Researchers in this study saw an opportunity to avoid these issues by switching from a solution-based method to a solvent-less method using a ball mill, in which reactants are shaken rapidly in a small metal jar along with a metal ball that smashes the solid reactants together.

“In previous studies, we found that using a ball mill for reactions of metals such as magnesium and calcium with organic compounds improved the reaction rate and greatly simplified the process,” said co-author Associate Professor Koji Kubota. “Based on this, we wondered if we could develop a more straight-forward Birch reduction process by performing reactions of lithium metal with aromatic compounds in a ball mill.”

The key to this strategy is that the mechanical impact from the ball breaks through the surface layer on the lithium that reacted with the air, exposing the pure lithium underneath to the other reactants and enabling the Birch reduction to proceed. This approach can be carried out in ambient air and at room temperature, making for a much easier process.

Researchers demonstrated the versatility of the process, successfully testing it with a wide variety of organic compounds, including pharmaceutical intermediates and other bioactive molecules. In most cases, the Birch reduction was completed in an astonishingly quick one minute.

The process was successfully scaled up to larger gram-scale batches, and the team believes this technique could enable the simplified synthesis of a wide variety of molecules, while also marking an important advance in mechanochemistry.

“The Birch reduction is used extensively in drug discovery and various chemical industries, and our research has made significant advancements, resulting in a much simpler and more eco-friendly Birch reduction process,” commented Professor Hajime Ito, who led the study. “We expect this breakthrough to accelerate drug discovery and various other areas of chemical research.”

Overview of the simplified protocol for the Birch reduction using a ball mill.

 (Yunpeng Gao, Koji Kubota, Hajime Ito. Agewandte Chemie International Edition. March 21, 2023)

JOURNAL

Angewandte Chemie International Edition

DOI

10.1002/anie.202217723 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Mechanochemical Approach for Air-Tolerant and Extremely Fast Lithium-Based Birch Reductions in Minutes

Non-drug interventions for patients with Alzheimer’s are both effective and cost-effective, study shows

A Brown-led research team used a computer simulation to show that compared to usual care, four dementia-care interventions saved up to $13,000 in costs, reduced nursing home admissions and improved quality of life.

Peer-Reviewed Publication

BROWN UNIVERSITY

PROVIDENCE, R.I. [Brown University] — While new drugs to treat Alzheimer’s disease tend to receive the most public attention, many well-researched ways to care for people with dementia don’t involve medication. A new evaluation compared the cost-effectiveness of four non-drug interventions to the usual care received by people with dementia and found that the interventions not only resulted in a better quality of life, but also saved money.

In a study published April 6 in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, researchers used a computer simulation model to show that the four dementia-care interventions saved between $2,800 and $13,000 in societal costs, depending on the type of intervention, and all reduced nursing home admissions and improved quality of life compared to usual care.

Alzheimer’s drugs hold great promise, but they still need additional research and improvement, said lead study author Eric Jutkowitz, an associate professor at Brown University’s School of Public Health. In the meantime, he said, a number of non-drug interventions have been shown to be effective in clinical trials in improving quality of life for people with dementia and helping them stay safely at home longer.

“Now that we can show that these effective interventions can also save money, it just makes sense to find ways to make them available to more families,” Jutkowitz said. “These interventions can be used to help people with dementia starting today.”

The four interventions studied included the following: Maximizing Independence at Home, an at-home, care coordination intervention that consists of care planning, skill-building, referrals to services and care monitoring; New York University Caregiver, which is implemented in an outpatient clinic and provides caregivers with six counseling sessions over four months plus lifetime ad-hoc support and access to weekly support groups; Alzheimer’s and Dementia Care, in which a health care system provides people living with dementia and their caregivers a needs assessment, individual care plans and round-the-clock access to a care manager; and Adult Day Service Plus, which augments adult day care services with staff providing face-to-face caregiver support, disease education, care management, skill-building and resource referrals.

Nonpharmacological interventions like these provide family caregivers with knowledge, skills and support tailored to their care challenges. They have been shown to improve quality of life for the caregiver and the person living with dementia, as well as to reduce nursing home admissions, and they are not associated with adverse events such as hospitalizations and mortality. For these reasons, nonpharmacological interventions are recommended as first-line therapies for the management of Alzheimer’s and dementia.

While non-drug interventions are well-studied, Jutkowitz said they haven't been widely implemented in clinical care centers. He added that there isn’t currently an infrastructure in place to support these methods of care — for example, there are limited mechanisms for providers to be reimbursed for these types of interventions.

To conduct the study, the researchers used a computer simulation to model the likelihood of nursing home admission for four evidence-based Alzheimer’s and dementia nonpharmacological interventions compared to usual care. For each, the study evaluated societal costs, quality-adjusted life-years and cost-effectiveness. The inputs in the simulation were based on data from Medicare, clinical trials and national surveys with families of people with dementia.

Jutkowitz noted that the researchers benefited not only from Brown University computing resources that could handle intensive analytic tasks, but also access to data from the government’s Centers for Medicare and Medicaid Services, which was crucial to the analysis.

In addition to finding that the interventions were cost-effective from a societal perspective, the researchers also found that from a health care payer perspective, the interventions involved little to no additional cost, compared to usual care, while increasing patient quality of life.

Based on the study findings, the authors concluded that health insurance policies should find ways to incentivize providers and health systems to implement nonpharmacological interventions.

The importance of understanding the cost-effectiveness of non-drug Alzheimer’s and dementia interventions is further highlighted by changes in Medicare payment models and emerging Alzheimer’s therapeutics, the researchers noted. The Centers for Medicare and Medicaid Services is in the process of determining coverage for new Alzheimer’s and related dementia drugs.

“As the Centers for Medicare and Medicaid Services determine coverage for new Alzheimer’s and related dementia drugs, we strongly believe that CMS should also consider the benefits of nonpharmacologic interventions,” Jutkowitz said.

While this study focused on non-drug interventions that reduce nursing home admissions, a future analysis will look at similar interventions that reduce or maintain functional decline and challenging behaviors. The researchers are also working on designing a trial that would test the interventions with patients in a health care setting.

Additional Brown contributors included Peter Shewmaker and Gary Epstein-Lubow.

This research was supported by the National Institute on Aging (1R21AG059623-01, 1R01AG060871-01, 1RF1AG069771, R01AG049692).

---

DOI

10.1002/alz.12964 

METHOD OF RESEARCH

Computational simulation/modeling

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Cost effectiveness of non-drug interventions that reduce nursing home admissions for people living with dementia

COI STATEMENT

Katherine M. Prioli conducted the research while at Rutgers University and is now an employee of OPEN Health. All authors report no conflicts of interest. Author disclosures are available in the supporting information.

Activating adult-born neurons through deep brain stimulation alleviates Alzheimer’s symptoms in rodent models

Peer-Reviewed Publication

CELL PRESS

 

IMAGE: ACTIVATION OF HYPOTHALAMIC-ENHANCED ADULT-BORN NEURONS RESTORES COGNITIVE AND AFFECTIVE FUNCTION IN ALZHEIMER’S DISEASE view more 

CREDIT: CELL STEM CELL/LI ET AL.

People with Alzheimer’s disease develop defects in cognitive functions like memory as well as problems with noncognitive functions that can lead to anxiety and depression. In a paper published April 6 in the journal Cell Stem Cell, investigators used mice to study a process through which new neurons are generated in adulthood, called adult hippocampus neurogenesis (AHN). The research showed that deep brain stimulation of new neurons helped restore both cognitive and noncognitive functions in mouse models of Alzheimer’s disease.

“We were surprised to find that activating only a small population of adult-born new neurons was enough to make a significant contribution to these brain functions,” says senior author Juan Song, an associate professor at the University of North Carolina at Chapel Hill. The neurons were modified by deep brain stimulation of the suprammamillary nucleus (SuM), which is located in the hypothalamus. “We are eager to find out the mechanisms that underlie these beneficial effects,” Song says.

This research used two distinct mouse models of Alzheimer’s. The investigators used optogenetics to stimulate the SuM and enhance AHN in Alzheimer’s mice. Their earlier research had shown that stimulation of the SuM could increase the production of new neurons and improve their qualities in normal adult mice. In the new study, the investigators showed that this strategy was also effective in the Alzheimer’s mice, leading to the generation of new neurons that made better connections with other parts of the brain.

However, having more improved new neurons is not enough to improve memory and mood. Behavioral improvement in Alzheimer’s mice were seen only when these improved new neurons were activated by chemogenetics. The researchers used memory tests as well as established assessments to look for anxiety-like and depression-like behavior to confirm these improvements. The results suggested that multi-level enhancement of new neurons—enhancement in number, properties, and activity—is required for behavioral restoration in Alzheimer's brains.

To further understand the mechanism, they also analyzed the protein changes in the hippocampus of Alzheimer’s mice in response to activation of SuM-modified adult-born new neurons. They found several well-known protein pathways activated inside cells, including those known to be important for improved memory performance, as well as those that allow clearance of the plaques related to Alzheimer’s.

“It was striking that multilevel enhancement of such a small number of adult-born new neurons made such a profound functional contribution to the animals’ diseased brains,” Song says. “We were also surprised to find that activation of SuM-enhanced neurons promoted the process that can potentially remove plaques.”

Future efforts of the team will focus on developing potential therapeutics that mimic the beneficial effects mediated by activation of SuM-modified new neurons. “We are hoping these drugs could exert therapeutic effects in patients with low or no hippocampal neurogenesis,” Song says. “Ultimately, the hope is to develop first-in-class, highly targeted therapies to treat Alzheimer’s and related dementia.”

###

This work was supported by the NIH, Alzheimer’s Association, Brain & Behavior Research Foundation, NIH- NINDS Neuroscience Center, NIH- NICHD Intellectual and Developmental Disabilities Research Center, and a UNC Pharmacology Curriculum predoctoral T32 training grant.

Cell Stem Cell, Li et al. “Activation of hypothalamic-enhanced adult-born neurons restores cognitive and affective function in Alzheimer’s disease” https://www.cell.com/cell-stem-cell/fulltext/S1934-5909(23)00043-7

Cell Stem Cell (@CellStemCell), published by Cell Press, is a monthly journal that publishes research reports describing novel results of unusual significance in all areas of stem cell research. Each issue also contains a wide variety of review and analysis articles covering topics relevant to stem cell research ranging from basic biological advances to ethical, policy, and funding issues. Visit: http://www.cell.com/cell-stem-cell. To receive Cell Press media alerts, contact press@cell.com.

---

JOURNAL

Cell Stem Cell

DOI

10.1016/j.stem.2023.02.006 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Animals

ARTICLE TITLE

Activation of hypothalamic-enhanced adult-born neurons restores cognitive and affective function in Alzheimer's disease

Random matrix theory approaches the mystery of the neutrino mass!

Peer-Reviewed Publication

OSAKA METROPOLITAN UNIVERSITY

 

IMAGE: THE HORIZONTAL AXIS SHOWS THE ORDINARY LOGARITHM OF THE NEUTRINO MASS SQUARED DIFFERENCE RATIO, WHILE THE VERTICAL AXIS SHOWS THEIR PROBABILITY DISTRIBUTION. EACH HISTOGRAMS REPRESENT THE PROBABILITY DISTRIBUTIONS FOR THE SEESAW MECHANISMS OF THE CORRESPONDING COLOR. THE VERTICAL RED AND BLUE LINES REPRESENT THE EXPERIMENTAL VALUES (1Σ AND 3Σ ERRORS) OF THE ORDINARY LOGARITHM OF THE NEUTRINO MASS SQUARED DIFFERENCE RATIO. THE PROBABILITY DISTRIBUTION FOR THE SEESAW MODEL WITH THE RANDOM DIRAC AND MAJORANA MATRICES IN ORANGE HAS THE HIGHEST PROBABILITY OF REPRODUCING THE EXPERIMENTAL VALUE. view more 

CREDIT: NAOYUKI HABA, OSAKA METROPOLITAN UNIVERSITY

When any matter is divided into smaller and smaller pieces, eventually all you are left with—when it cannot be divided any further—is a particle. Currently, there are 12 different known elementary particles, which in turn are made up of quarks and leptons each of which come in six different flavors. These flavors are grouped into three generations—each with one charged and one neutral lepton—to form different particles, including the electron, muon, and tau neutrinos. In the Standard Model, the masses of the three generations of neutrinos are represented by a three-by-three matrix.

A research team led by Professor Naoyuki Haba from the Osaka Metropolitan University Graduate School of Science, analyzed the collection of leptons that make up the neutrino mass matrix. Neutrinos are known to have less difference in mass between generations than other elementary particles, so the research team considered that neutrinos are roughly equal in mass between generations. They analyzed the neutrino mass matrix by randomly assigning each element of the matrix. They showed theoretically, using the random mass matrix model that the lepton flavor mixings are large.

“Clarifying the properties of elementary particles leads to the exploration of the universe and ultimately to the grand theme of where we came from!” Professor Haba explained. “Beyond the remaining mysteries of the Standard Model, there is a whole new world of physics.”

After studying the neutrino mass anarchy in the Dirac neutrino, seesaw, double seesaw models, the researchers found that the anarchy approach requires that the measure of the matrix should obey the Gaussian distribution. Having considered several models of light neutrino mass where the matrix is composed of the product of several random matrices, the research team was able to prove, as best they could at this stage, why the calculation of the squared difference of the neutrino masses are closest with the experimental results in the case of the seesaw model with the random Dirac and Majorana matrices. 

“In this study, we showed that the neutrino mass hierarchy can be mathematically explained using random matrix theory. However, this proof is not mathematically complete and is expected to be rigorously proven as random matrix theory continues to develop,” said Professor Haba. “In the future, we will continue with our challenge of elucidating the three-generation copy structure of elementary particles, the essential nature of which is still completely unknown both theoretically and experimentally.”

Their findings were published in Progress of Theoretical and Experimental Physics.

###

About OMU 

Osaka Metropolitan University is a new public university established by a merger between Osaka City University and Osaka Prefecture University in April 2022. For more science news, see https://www.omu.ac.jp/en/, and follow @OsakaMetUniv_en, or search #OMUScience.

---

JOURNAL

Progress of Theoretical and Experimental Physics

DOI

10.1093/ptep/ptad010 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

Not applicable

ARTICLE TITLE

Neutrino mass square ratio and neutrinoless double beta decay in random neutrino mass matrices

Understanding inflorescence architecture in woodland strawberry provides tools for crop improvement

Peer-Reviewed Publication

UNIVERSITY OF HELSINKI

 

IMAGE: RESEARCHERS DEMONSTRATED HOW STRAWBERRY INFLORESCENCE DEVELOPMENT IS DICTATED BY THE SMALL GROWING POINTS, CALLED MERISTEMS. view more 

CREDIT: MIKOLAJ CIESLAK JA PRZEMYSLAW PRUSINKIEWICZ.

Researchers from the University of Helsinki, in collaboration with their Canadian colleagues, have demonstrated how strawberry inflorescence development is dictated by the small growing points, called meristems. This research provides tools for plant breeding based on genetic information and for improving yields of the more genetically complex cultivated strawberry.

Woodland strawberry is a familiar plant for many of us. It is also a very convenient model plant for biological research – it is easy to cultivate in greenhouses, and its small genome is fully known. Researchers at the Department of Agricultural Sciences, University of Helsinki, have focused on exploring the genetic mechanisms that regulate inflorescence  architecture in woodland strawberry. With the help of transgenic strawberry plants, they have identified gene functions that affect the complexity of inflorescences.  

“Our aim is to understand the mechanisms behind the diversity of plant structures and forms in nature. In this research, we explored how the level of branching varies in strawberry inflorescences and consequently affects the berry yield of the plant,” says Professor Timo Hytönen, the corresponding author of the study.

Researchers demonstrated how strawberry inflorescence development is dictated by the small growing points, called meristems. Strawberry meristems, located at the tips of the shoots, may either terminate into a flower or produce new meristems to form a branch. The timing of these events affects the branching iterations, the final number of flowers, and eventually the number of berries in the inflorescences.

Interestingly, strawberry inflorescences combine two branching systems – a monopodial primary axis and sympodial lateral branches – and are botanically known as thyrses. The development of thyrse architecture has not been previously explored in any other plant.

“Firstly, our discovery shows how the thyrse architecture in strawberry emerges from geometrically distinct meristems, and secondly, we provide molecular data showing how two antagonistically functioning genes regulate the fate of these meristems,” explains doctoral researcher Sergei Lembinen.

In collaboration with computer scientists at the University of Calgary, the molecular data was integrated into a computational model to create virtual strawberry plants. Together with experimental data, the model helps us to understand the complex interactions and mechanisms that affect inflorescence architecture. The model explains and captures the extensive variability of inflorescence architectures in strawberry, documented by the botanist George McMillan Darrow almost a century ago.

“By exploring the diversity of plant species, and the specific features in their development, we gain a basic understanding of how genetic mechanisms governing plant development have been modified during evolution. Moreover, this research provides us with tools for genomics-based plant breeding in the genetically more complex cultivated strawberry,” summarizes Professor Hytönen.

---

JOURNAL

The Plant Cell

DOI

10.1093/plcell/koad086 

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Diversity of woodland strawberry inflorescences arises from heterochrony regulated by TERMINAL FLOWER 1 and FLOWERING LOCUS T

Simple, environmentally friendly coating can improve battery performance

Peer-Reviewed Publication

CHINESE ACADEMY OF SCIENCES HEADQUARTERS

 

IMAGE: MOLECULAR FERROELECTRIC COATING INHIBITS THE SPACE CHARGE LAYER AND ENHANCES THE LI+ TRANSPORT AT THE CATHODE/ELECTROLYTE INTERFACE view more 

CREDIT: LI WENRU AND MA JUN

Lithium-ion batteries are currently the gold standard of battery technology, but as the demand for safe and effective batteries increases, researchers are racing to find what's next.

All-solid-state lithium batteries could be an alternative to current lithium-ion battery technology, but improvements in their capacity are needed.

A new study led by researchers from the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences details how ferroelectric cathode coatings boost the capacity of all-solid-state lithium batteries.

The study was published in Advanced Functional Materials on March 28.

Ferroelectric materials possess an inherently polarized electric field that is widely used to accelerate the separation and transfer of charges in many electrochemical types of research.

"In the field of all-solid-state lithium batteries, it is widely accepted that the ferroelectric polarization induces the built-in electric field at the electrode/solid-state electrolytes interface, which could suppress the space charge layer and boost lithium transportation," said Dr. LI Wenru, first author of the study. "However, the construction mechanism of the ferroelectric built-in electric field in these batteries is poorly understood. Revealing this construction mechanism becomes a critical challenge."

To understand more about how the ferroelectric material improves battery function, the researchers covered the lithium cobalt oxide cathode in a coating layer made from an organic-inorganic hybrid ferroelectric material called guanidinium perchlorate. Guanidium perchlorate coatings were found to possess a single-domain state, meaning the inner ferroelectric dipoles point to one same direction. This behavior finally generates the downward built-in electric field at the cathode/electrolyte interface. By the way, guanidium perchlorate can be made by evaporating solvents like ethyl alcohol, making it an inexpensive and environmentally friendly option for battery manufacturing.

The researchers found out that the capacities of the all-solid-state lithium batteries with the ferroelectric coating on the cathode are nearly the same as current liquid lithium-ion battery, which is much higher than the all-solid-state lithium batteries using the uncoated cathode.

They also analyzed how the active particles interacted with the electrolyte in the cathode with and without the coating. A space charge layer, which interferes with the movement of electrons through the battery, forms when the lithium cobalt oxide meets the solid-state electrolyte. The space charge layer restricts the transport of the lithium and reduces the capacity of the battery. When the coatings were coated onto the cathode, the effective ferroelectric built-in electric field made the lithium move more fluently through the cathode/electrolyte interface, improving the capacity of the battery despite the space charge layer.

"We found that the flexoelectric effect caused by the lattice mismatch is the primary factor for the self-polarization effect of the coatings. Our study not only designs the all-solid-state lithium batteries with excellent electrochemical performance, but also discovers the scientific theoretical guidance for constructing the ferroelectric coating layers in promoting performances of electrochemical energy storage," said Dr. LI.

Looking ahead, the researchers will look at different combinations of materials to expand the possibilities for all-solid-state lithium batteries. "We hope to expand this research idea to different combinations of cathode and ferroelectric materials in future work, and obtain experimental rules for optimal battery performance," said Prof. CUI Guanglei, corresponding author and the group leader of Solid Energy System Technology Center at QIBEBT. "The ultimate goal is to have a universal strategy improving lithium battery performance in practical applications."

---

JOURNAL

Advanced Functional Materials

DOI

10.1002/adfm.202300791 

ARTICLE TITLE

Self-Polarized Organic–Inorganic Hybrid Ferroelectric Cathode Coatings Assisted High Performance All-Solid-State Lithium Battery