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Interface instabilities in hafnium hydride entrained iron metal matrix composites

The chemical interactions in Fe–HfH2 metal matrix composites (MMCs) are studied across multiple length scales to elucidate the decomposition of the parent phases and corresponding reaction zone physics during direct current sintering. Fe–HfH2 composites were synthesized with increasing as-mixed hydride contents of Fe–25% HfH2, Fe–40% HfH2, Fe–55% HfH2, and Fe–70% HfH2 (all in vol. %) to demonstrate the ability to achieve sintered MMCs with target hydride contents. Samples were probed across multiple length scales through a multi-modal workflow employing x-ray diffraction, scanning electron microscopy and segmentation analysis, and synchrotron techniques including hard x-ray fluorescence mapping and nanoprobe x-ray absorption near-edge structure measurements. Under the selected sintering temperature and pressure conditions, hydrogen evolution is seen to evolve through parallel paths: thermal decomposition from during the transformation of HfH2 to HfHx<2 and through subsequent reaction with the Fe matrix leading to intermetallic phase formation. Specifically, HfFe and HfFe2 intermetallic formation accelerates the release of hydrogen with a subsequent HfO2 phase forming at grain boundaries. For this MMC, the consumption or loss of hydrogen can be considerable in compacts with initial hydride loading of 25%–40% HfH2 approaching 83% hydrogen loss for the lower volume fraction composites. Increasing the volume fraction of HfH2 to 70% enhanced the retained hydrogen content to 53% and attributed to the reduced interfacial area intrinsic to the increased HfH2 loading in this MMC.

Agrivoltaics shading enhanced the microclimate, photosynthesis, growth and yields of vigna radiata genotypes in tropical Nigeria

Precisely designing asymmetrical selenium-based dual-atom sites for efficient oxygen reduction

Impact of Smokeless Oral Nicotine Products on Cardiovascular Disease: Implications for Policy, Prevention, and Treatment: A Policy Statement From the American Heart Association

Smokeless oral nicotine products are addictive, and their use has potential adverse effects on some but not all biomarkers of cardiovascular risk. The use of some types of these products, for instance, is associated with an increased mortality risk in those with ischemic heart or cerebrovascular disease. Similarly, smokeless tobacco has the potential to increase the risk of oral cancer, but the risks depend on the chemical composition of the product. The market of smokeless oral nicotine products has transformed since the last American Heart Association smokeless tobacco policy statement. Several varieties of tobacco-free oral nicotine products—including oral nicotine pouches; nontherapeutic nicotine gums, lozenges, and tablets; and nicotine gummies—have rapidly proliferated. The sales of oral nicotine pouches, in particular, have increased substantially; however, no data are available on their cardiovascular or health risks. In addition, synthetic (compared with tobacco-derived) nicotine has been used in some brands of oral nicotine products, but its cardiovascular and health effects have been inadequately studied. Robust public policy levers are identified to support ending addiction to all commercial tobacco products. Critical components and policy initiatives include clinicians emphasizing the prevention of tobacco product initiation and supporting cessation with established pharmacological and behavioral tobacco dependence treatment therapies as primary goals for achieving an end to commercial tobacco and nicotine addiction.

Frictional heating in cyclotrimethylene trinitramine during nanoscratching: Plasticity and localized melting

Frictional heating in cyclotrimethylene trinitramine (RDX) can generate hotspots, which are local regions of elevated temperature that may trigger explosion. In this study, we quantified the characteristic size of the hotspot to be approximately 20 Å based on the width of the nanoscale shear band in shock loading simulations and further examined the temperature rise in RDX crystals during high-speed nanoscratching using molecular dynamics simulations. These simulations were performed under varying sliding velocities, normal loads, and sliding directions to explore the relationship between friction coefficient, shear stress, and localized hotspots. Our results revealed that, despite the anisotropic friction properties, the temperature rise exhibited a consistent dependence on shear stress, with a critical shear stress identified above which the hotspots experienced a sharp increase in the temperature. This temperature transition correlates with localized melting, as demonstrated by the analysis of atomic temperature and bond-length changes. These findings enhance our understanding of the mechanical and thermal stability of energetic materials.

Evolutionary game of international trade network based on trade policy differences

Exciton-polariton ring Josephson junction

<i>Circulation</i> Editors and Editorial Board

Sorption of gases by disordered materials: A model based on the glass transition effect

Disordered materials in the glassy state show different gas sorption properties compared to same materials in the liquid or rubbery state. The sorption enthalpy becomes more exothermic, and the absorbed amount is greater compared to the liquid or rubbery state. The sorption data are often treated in the literature using the dual-mode theory—a three-parameter sorption model. This work presents another approach where a gas sorption isotherm model for glassy materials is derived from thermodynamic consideration of glass transition properties. The model is particularly applicable for describing sorption data that obey Henry's law in the limit of the liquid or rubbery state. The model parameters correspond to physically meaningful characteristics of the system's glass transition. We demonstrate that experimental gas sorption data, when plotted as ln(P/C) vs C, exhibit linear behavior in both the rubbery and glassy states, enabling accurate determination of the glass transition point from isothermal data. Additionally, gas sorption in glassy disordered materials can be effectively described using a two-parameter function based on the Lambert W function.

Mechanistic insights into gut microbe derived siderophores and PHD2 interactions with implications for HIF-1α stabilization

Geographic Disparities in Availability of Hospital-Based Cardiac Services Across the United States

Million-atom heat transport simulations of polycrystalline graphene approaching first-principles accuracy enabled by neuroevolution potential on desktop GPUs

First-principles molecular dynamics simulations of heat transport in systems with large-scale structural features are challenging due to their high computational cost. Here, using polycrystalline graphene as a case study, we demonstrate the feasibility of simulating heat transport with near first-principles accuracy in systems containing over 1.4×106 atoms, achievable even with consumer desktop GPUs. This is enabled by the highly efficient neuroevolution potential (NEP) approach, as implemented in the open-source GPUMD package. Leveraging the NEP model’s accuracy and efficiency, we quantify the reduction in thermal conductivity of polycrystalline graphene due to grain boundaries with varying grain sizes, resolving contributions from in-plane and out-of-plane (flexural) phonon modes. Additionally, we find that grain boundaries can lead to finite thermal conductivity even under significant tensile strain, in contrast to the divergent behavior observed in pristine graphene under similar conditions, indicating that grain boundaries may play a crucial role in thermal transport in low-dimensional momentum-conserving systems. These findings could offer insights into interpreting experimental observations, given the widespread presence of both large-scale grain boundaries and external strains in real materials. The demonstrated ability to simulate millions of atoms with near-first-principles accuracy on consumer desktop GPUs using the NEP approach will help make large-scale high-fidelity atomistic simulations more accessible to the broader research community.

Research on detection and treatment of loose zones in weak fracture zone tunnel

YAP Overcomes Mechanical Barriers to Induce Mitotic Rounding and Adult Cardiomyocyte Division

BACKGROUND: Many specialized cells in adult organs acquire a state of cell cycle arrest and quiescence through unknown mechanisms. Our limited understanding of mammalian cell cycle arrest is derived primarily from cell culture models. Adult mammalian cardiomyocytes, a classic example of cell cycle arrested cells, exit the cell cycle postnatally and remain in an arrested state for the life of the organism. Cardiomyocytes can be induced to re-enter the cell cycle by YAP5SA, an active form of the Hippo signaling pathway effector YAP. METHODS: We performed clonal analyses to determine the cell cycle kinetics of YAP5SA cardiomyocytes. We also performed single-cell RNA sequencing, marker gene analysis, and functional studies to examine how YAP5SA cardiomyocytes progress through the cell cycle. RESULTS: We discovered that YAP5SA-expressing cardiomyocytes divided efficiently, with &gt;20% of YAP5SA cardiomyocyte clones containing ≥2 cardiomyocytes. YAP5SA cardiomyocytes re-entered cell cycle at the G1/S transition and had an S phase lasting ≈48 hours. Sarcomere disassembly is required for cardiomyocyte progression from S to G2 phase and the induction of mitotic rounding. Although oscillatory Cdk expression was induced in YAP5SA cardiomyocytes, these cells inefficiently progressed through G2 phase. This is improved by inhibiting P21 function, implicating checkpoint activity as an additional barrier to YAP5SA-induced cardiomyocyte division. CONCLUSIONS: Our data reveal that YAP5SA overcomes the mechanically constrained myocardial microenvironment to induce mitotic rounding with cardiomyocyte division, thus providing new insights into the in vivo mechanisms that maintain cell cycle quiescence in adult mammals.

Hydrogen-terminated single crystal diamond MOSFET with the dielectric of Ga2O3

In this work, the first fabrication and investigation of normally-off single crystal hydrogen-sterminated diamond MOSFETs with Ga2O3 dielectric has been successfully carried out. 50-nm-thick Ga2O3 was deposited by electron-beam evaporation technique at room temperature. The maximum drain current was −36 mA/mm, which was 164 times larger than previous work. Based on the transfer characteristic curve, the threshold voltage, on/off ratio and extrinsic transconductance were −0.37 V, 2.3 × 107, and 9.8 mS/mm, respectively. The effective mobility of the MOSFET was calculated to be 264.1 cm2/V ⋅s at VGS = − 1 V. This work may significantly promote the application of H-diamond FETs.

Evaluating the effectiveness of different intervention measures for an outbreak of mycoplasma pneumoniae in hangzhou based on a dynamic model

Efficacy and Safety of Finerenone Across the Ejection Fraction Spectrum in Heart Failure With Mildly Reduced or Preserved Ejection Fraction: A Prespecified Analysis of the FINEARTS-HF Trial

BACKGROUND: The effects of treatments for heart failure (HF) may vary among patients according to left ventricular ejection fraction (LVEF). In FINEARTS-HF (Finerenone Trial to Investigate Efficacy and Safety Superior to Placebo in Patients With Heart Failure), the nonsteroidal mineralocorticoid receptor antagonist finerenone reduced the risk of cardiovascular death and total worsening HF events in patients with HF with mildly reduced or preserved ejection fraction. We examined the effect of finerenone according to LVEF in FINEARTS-HF. METHODS: FINEARTS-HF was a randomized, placebo-controlled trial examining the efficacy and safety of finerenone in patients with HF and LVEF ≥40%. The treatment effect of finerenone was examined in prespecified analyses according to LVEF categories (&lt;50%, ≥50% to &lt;60%, and ≥60%) and with LVEF as a continuous variable. The primary outcome was a composite of total (first and recurrent) worsening HF events and cardiovascular death. RESULTS: Baseline LVEF data were available for 5993 of the 6001 participants in FINEARTS-HF. Mean and median LVEF were 53±8% and 53% (interquartile range, 46%–58%), respectively. LVEF was &lt;50% in 2172 (36%), between 50% and &lt;60% in 2674 (45%), and ≥60% in 1147 (19%). Patients with higher LVEF were older, were more commonly female, were less likely to have a history of coronary artery disease, and more frequently had a history of hypertension and chronic kidney disease compared with those with a lower LVEF. Finerenone reduced the risk of cardiovascular death and total HF events consistently across LVEF categories (LVEF &lt;50% rate ratio, 0.84 [95% CI, 0.68–1.03]; LVEF ≥50% to &lt;60% rate ratio, 0.80 [0.66–0.97]; and LVEF ≥60% rate ratio, 0.94 [0.70–1.25]; P interaction =0.70). There was no modification of the benefit of finerenone across the range of LVEF when analyzed as a continuous variable ( P interaction =0.28). There was a similar consistent effect of finerenone on reducing the total number of worsening HF events (continuous P interaction =0.26). CONCLUSIONS: In patients with HF with mildly reduced or preserved ejection fraction, finerenone reduced the risk of cardiovascular death and worsening HF events, irrespective of LVEF. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04435626. URL: https://eudract.ema.europa.eu ; Unique identifier: 2020-000306-29.

Charge-mediated electric control of the perpendicular magnetic anisotropy in Fe–Ga/PMN-PT composite multiferroic

We present an experimental study of the magnetoelectric coupling in the Fe-Ga/Pb[(Mg1/3Nb2/3)O3]0.68-[PbTiO3]0.31 thin-film multiferroic composite using x-ray magnetic circular dichroism and ferromagnetic resonance (FMR). Our measurements show evidence for a charge-mediated coupling mechanism, suggested by the asymmetric magnetic remanence (Mrem) behavior under opposite electric fields (±E) and the asymmetric resonance field (Hr) in the FMR measurements. Also, the FMR measurements reveal a perpendicular magnetic anisotropy that can be related to an interface charge effect and it is tunable by the E field. Ab initio calculations support the existence of a charge-mediated coupling at the Fe–Ga/PMN-PT interface.

Novel insights into insect mediated polystyrene biodegradation through bacterial genome analyses

Abstract Plastic pollution is a significant environmental challenge of contemporary age. Polystyrene (PS), among the most commonly used plastic polymers worldwide, is highly durable and difficult to degrade. Despite various disposal strategies, PS continues to impact biodiversity, human health, and ecosystems. Recently, the scientific community has focused on the potential role of microorganisms for plastic biodegradation, particularly those from the gut of plastivorous insects. In a previous study, three bacterial strains, each representing a distinct taxonomic group (Klebsiella, Pseudomonas, and Stenotrophomonas), were isolated from Alphitobius diaperinus larvae after rearing on a PS diet and enriched in a medium with PS as the sole carbon source. The Stenotrophomonas sp. strain, here identified as S. indicatrix, showed the greatest potential for PS degradation. The present study investigates the genetic profile of the newly isolated S. indicatrix strain DAI2m/c through genome sequencing, to identify enzyme-encoding genes involved in the intracellular metabolic pathways responsible for the biodegradation of the styrene monomer. Our findings indicate that the genome of S. indicatrix strain DAI2m/c encodes all enzymes required for one of the two recognized styrene degradation pathways, suggesting its ability to convert styrene into byproducts that are then utilized for cellular energy production.

Cardiovascular-Liver-Metabolic Health: Recommendations in Screening, Diagnosis, and Management of Metabolic Dysfunction-Associated Steatotic Liver Disease in Cardiovascular Disease via Modified Delphi Approach

There is a new awareness of the widespread nature of metabolic dysfunction–associated steatotic liver disease (MASLD) and its connection to cardiovascular disease (CVD). This has catalyzed collaboration between cardiologists, hepatologists, endocrinologists, and the wider multidisciplinary team to address the need for earlier identification of those with MASLD who are at increased risk for CVD. The overlap in the pathophysiologic processes and parallel prevalence of CVD, metabolic syndrome, and MASLD highlight the multisystem consequences of poor cardiovascular–liver–metabolic health. Metabolic dysfunction and associated insulin resistance, together with the predilection for ectopic fat deposition in the liver and surrounding tissues, are associated with elevated risk of endothelial dysfunction, systemic inflammatory response, and ectopic fat deposition in the epicardium. This complex pathophysiology can accelerate atherogenic dyslipidemia, atherogenesis, diastolic dysfunction, valvular calcification, and cardiac arrhythmias. Despite the mounting evidence of mechanistic pathways underpinning MASLD and CVD, current recommendations have not clearly focused upon MASLD as a risk factor or target for intervention in CVD. We have brought together a diverse range of international experts committed to promoting cardiovascular–liver–metabolic health and related outcomes across the globe. The overarching goal of this document is to offer a construct for clinicians in the cardiovascular field with regards to (1) diagnosis and screening of MASLD through the use of noninvasive serum and imaging tests; (2) screening for CVD in all individuals with MASLD regardless of established atherosclerotic risk factors; and (3) the approach to management of MASLD with respect to prevention of CVD through lifestyle, as well as pharmacologic and surgical strategies. To achieve this, the modified Delphi method was applied and a series of evidence-based quality standard recommendations have been identified.