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Methionine Salvage Enzyme Uses a Unique Mechanism to Overcome a Challenging Aldose–Ketose Isomerization

Evaluating N95 respirator designs: A mixed-methods pilot and feasibility study

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a global impact, underscoring the importance of personal protective equipment (PPE). Use of N95s reduces the risk of airborne infection; however, in the absence of equitable designs, health care workers (HCWs) who do not fit the average White male head and face are at an increased risk of airborne infectious diseases. Objectives Primary: Feasibility of a mixed-method study, with a sample size of 100, 50% of participants self-identifying as non-White and having at least one characteristic of interest. Secondary: (1) Generate quantitative evidence on N95 fit using a PortaCount fit test, (2) describe participant-reported feelings on fit and breathability, and (3) evaluate the impacts of the pandemic on a HCW’s physical and mental well-being. Methods This was a mixed-method prospective pilot and feasibility study. Quantitative fit was assessed using a TSI PortaCount test and measurements of bizygomatic breadth and Menton-Sellion length. A survey was administered to collect sociodemographic information, HCWs’ assessment of N95 fit, comfort, and the impact of PPE-related challenges on well-being. Results This study was limited by a small sample size, as COVID-19 pandemic restrictions prevented adequate recruitment to detect differences between groups. We describe key findings that should inform analyses of the impact of gender and ethnicity on N95 respirator fit. Following a study amendment to increase eligible sites, 37 of the 41 (90.2%) approached HCWs consented to participate. Compared to other HCWs, non-White females had the lowest mean fit factor. Differences in Menton-Sellion length and bizygomatic breadth were observed between males, females, and White and non-White HCWs. Most HCWs reported physical discomfort and negative impacts on their psychological well-being. Conclusions We identified gender and ethnicity as key factors in the fit of N95s. Differences in gender, ethnicity, and anthropometric measures must be considered in respirator designs.

Triple-Conduction-Band Activation Enables High Out-of-Plane Thermoelectric Efficiency in n-type SnS Crystals

What do future physicians think of traditional, complementary, and integrative medicine (TCIM)? Fifteen years after the inclusion of TCIM in the Swiss constitution

Background An increasing recognition of traditional, complementary and integrative medicines’ (TCIM) contributions for public health has driven the development of international policy recommendations for its inclusion into national healthcare systems. While many countries have made advances in the incorporation of TCIM in academic medicine, there are globally only a handful that have a constitutional mandate in this context. The present cross-sectional study focused on one of these, namely Switzerland, some fifteen years after TCIM was included into the country’s Federal Constitution. Aims & methods This research aimed to examine attitudes of the future medical workforce in regard to TCIM within the only European country in which TCIM is mandated by the constitution. More specifically, using an online survey tailored to the country’s socio-political context, this study assessed attitudes, knowledge, and expectancies regarding TCIM among medical students across all Swiss universities that offer degrees in human medicine. Results Even though Swiss medical schools have consolidated and expanded their TCIM-related curricula compared to earlier assessments, with all of them now offering mandatory TCIM classes, most participants were unaware of this. Nonetheless, two-thirds of the N  = 695 participants considered TCIM a valuable extension of conventional medicine that should have a place in medical education. Views diverged greatly between TCIM modalities. Further, we found significant differences as a function of gender and linguistic regions, although in the latter case effect sizes were modest. Conclusions Knowing the views of medical students as the future generation of physicians, clinical scientists, and often also decision-makers in the context of policy-driven integration is crucial in understanding the future trajectory of TCIM into mainstream healthcare. Based on Switzerland’s unique experience and history in this context this work contributes to the broader discourse on the role of TCIM in national healthcare systems.

Reactions of Radical Anions with Hydrides: Supercharging Electron Upconversion for Electron Catalysis

Age is just a number: Examining the preservation of cells and soft tissues in Bothriolepis and other Devonian fish

Recent microscopy and proteomic studies demonstrate fossil bones can preserve remarkable palimpsests of cellular and soft tissue evolution, yet it remains unclear if there are temporal limits to such preservation. For instance, it remains unknown if fossil cells and soft tissues can be recovered from fossil bones of the earliest vertebrates from the middle Paleozoic. To test this, we demineralized nine bone fragments of Bothriolepis and other Late Devonian fish. Removal of phosphates from the fossils released numerous microstructures morphologically consistent with vertebrate osteocytes, pieces of blood vessels, and sheets of fibrous bone matrix which were frequently found to exhibit elemental chemistry potentially indicative of partial organic composition. These discoveries extend this style of exceptional preservation to aspidin and dentine and predate all prior reports of similar cellular/soft-tissue preservation in fossil bones by nearly 100 million years, indicating that the geologic age of a fossil specimen is a poor predictor of whether or not it will retain potentially-endogenous microstructures. Thus, the preservation pathways leading to these forms of soft-tissue fossilization likely began contemporaneously with the evolution of vascularized cellular bone in the early Paleozoic.

Ultralow Contact Resistance in Two-Dimensional Semiconductor Transistors Approaching the Quantum Limit

Care cascade of hypertension across stages among older adults in India

Hypertension is now a common disease and the single largest risk factor for premature mortality in India. Hypertensive individuals are not homogenous and have varying risks to life. Although the number of studies on the care cascade of hypertension in India is increasing, no attempts have been made to estimate the prevalence and cascade of care across different stages of hypertension. This study estimates the prevalence, awareness, and treatment of hypertension by stages of hypertension among older adults in India. We analyzed data on 58,787 adults aged 45 years and above from the Longitudinal Ageing Study in India (LASI), Wave 1 (2017−18). Hypertension stages were categorized in accordance with the classification given by the Ministry of Health and Family Welfare, Government of India, and regrouped as per global classification. The age-sex adjusted prevalence, awareness, and treatment rates for different stages of hypertension were estimated. Multinomial logistic regression and the Erreygers’ Concentration Index were used to assess socioeconomic inequalities in hypertension care. We estimated the prevalence of pre-hypertension at 39.9%, stage 1 hypertension at 22.1% and stage 2 hypertension at 9.9%. Increasing age and body mass index were associated with a higher chance of hypertension, whereas living with spouses and children meant having lower odds of hypertension across all stages. The economic condition of the household, educational attainment, and social groups were not significant predictors of hypertension across the stages. The awareness and treatment of hypertension were low across all the stages. The Erreygers’ Concentration Index on awareness and treatment was pro-rich across all the stages of hypertension. A large proportion of hypertensive patients at the advanced stage remain undiagnosed and untreated and carry a higher risk of premature mortality. The awareness and treatment of hypertension are lower among the poorer and socially disadvantaged populations than their richer and more privileged counterparts across all stages.

Supramolecular Ionic Polymerization: Cellulose-Based Supramolecular Plastics with Broadly Tunable Mechanical Properties

Shared and distinct microRNA profiles between HT22, N2A and SH-SY5Y cell lines and primary mouse hippocampal neurons

MicroRNAs (miRNA) are small non-coding RNAs that are key negative regulators of gene expression. Their roles include shaping the gene expression landscape during and after brain development by defining and maintaining levels of proteins that generate the distinct morphological and functional properties of neurons and other brain cell types. HT22, N2A, and SH-SY5Y are common immortalized neuronal cell lines that offer simple, less expensive, and time-saving options for in vitro modelling to evaluate miRNA functions. The extent to which these lines reflect primary neurons remains, however, unclear. Here, we benchmarked the miRNA profiles of cultured mouse hippocampal neurons against Argonaute-loaded miRNAs in the adult mouse hippocampus and miRNA data from the hippocampus of control human donors. We then compared the miRNA expression landscape in HT22, N2A and SH-SY5Y against mouse hippocampal primary cell cultures. We profiled over 700 miRNAs across the lines and detected 310 miRNAs in all four cell types. This included detection of neuron-enriched miRNAs such as miR-124 and miR-128, although the cell lines typically displayed lower levels of these than in primary neurons and reference adult hippocampal tissue. The miRNA profile in the HT22 cell line showed the highest correlation to the mouse primary neuronal cultures. Together, this study provides a dataset on basal miRNA expression across commonly used cell lines for neuroscience research and evidence for both conserved and distinct profiles that should be used to inform decisions on cell lines for modelling brain and miRNA research.

Single-Crystal-to-Single-Crystal Radical-Ion Chain Reactions under the Electron Microscope: A Chemical Design to Repurpose Electron Beam Damage

Experimental study on the homogeneity of microbial grouting to reinforce calcareous sand

Microbial-induced calcium carbonate precipitation (MICP) technology has shown remarkable potential in environmental engineering fields, such as soil improvement, pollution control and hydrological barrier construction. However, when applied to the reinforcement of sandy materials, the main challenge of MICP technology is the nonuniformity of the curing effect, which greatly restricts the application of this technology in practical engineering. The aim of this study is to explore and optimise the application of MICP technology in calcareous sand reinforcement to improve the uniformity and efficiency of the reinforcement. By treating calcareous sand samples from an island in the South China Sea with Pasteurella spp. octococcus and conducting 75 unconfined compressive tests, the effects of different filling rates (0.5, 3, and 7 mL/min), cementing solution concentrations (0.25, 0.5, 1, and 3 mol/L), and numbers of filling rounds (2, 4, 6, and 8 rounds) on the homogeneity of the reinforcement were systematically investigated. The best curing effect was achieved at an infusion rate of 3 mL/min, which improved the strength of the soil while maintaining a high degree of uniformity. A good balance between compressive strength and uniformity was achieved at cement concentrations ranging from 0.5 mol/L to 1 mol/L. Increased grouting effectively improved the distribution uniformity of the MICP cemented structure. The destructive strain εf of the cured specimens ranged from 1.5% to 6%, which was inversely proportional to the peak strength qu; the elastic modulus E50 was positively correlated with qu. The stress‒strain curves were characterised by three phases of slow increase, rapid increase and sudden decrease in stress under different binder concentration conditions. For the unevenly cured samples, the stress‒strain curves were disordered, and there were multiple stages of stress peaks. This work confirmed that the MICP technique can significantly enhance the mechanical properties of calcareous sand, but precise control of the filling parameters is needed to ensure the uniformity and efficiency of the reinforcement. The suggested optimised parameters are as follows: a filling rate of 3 mL/min, a cementitious solution concentration of 0.5 mol/L to 1 mol/L, and a reasonable number of filling. This study provides a theoretical basis and practical guidance for the application of MICP technology in calcareous sand reinforcement scenarios.

Photoenzymatic C(sp ³ )–H Functionalization of 1,3-Dicarbonyls Enables Enantioselective Hydroalkylation of Styrenes

Comparability of accelerometry outcomes across popular metrics and widespread sensor positions

Accelerometry is a state-of-the-art procedure to capture physical activity. However, the large variety of accelerometry metrics and wearing positions hamper the comparability of outcomes. Since this is a well-known challenge, we investigated how outcomes can be translated across four metrics and six sensor positions. Twenty healthy adults conducted 32 structured and semi-structured activities while wearing accelerometers at the hip, chest, thigh, wrist, ankle, and upper arm. The raw data was converted into four common metrics: Movement Acceleration Intensity (MAI), Euclidean Norm Minus One (ENMO), Mean Amplitude Deviation (MAD) and counts per minute (CPM), as computed by the Actigraph GT3X+ algorithm. Relationships between acceleration metrics and sensor positions were quantified via Pearson correlations and scatterplots. Our results show that nearby sensor positions were highly correlated (e.g., MAD hip and thigh: r  = .96), while correlations between more distant sensor positions were weaker and less linear (e.g., MAD wrist and thigh: r  = .80). Correlations between MAI, MAD and ENMO were high ( r  = .9), while correlations between CPM and other metrics were substantially lower ( r  = .78), less linear, and influenced by activity type. Thus, linear conversion between MAI, ENMO and MAD are highly feasible, but converting CPM may be less accurate. Linear conversions between nearby sensor positions are accurate, yet linear conversions between more distant sensor positions appear challenging. Importantly, based on 32 activities as well as metric- and sensor-location-specific configurations, we provide a comprehensive overview of outcome measures that enables researchers to individually explore conversion opportunities towards their own data.

Oxygenated Carbon Electrocatalysts for Chlorine Evolution Reaction

Translocation of benzo(a)pyrene reactive metabolites across human mammary epithelial cell membranes

DNA adducts from benzo(a)pyrene (BaP) and other polycyclic aromatic hydrocarbons (PAH) are related to tumor initiation in many tissues including mammary epithelia. T47D mammary cells are able metabolizers of BaP, forming DNA and cellular protein adducts but also a sizeable amount of extracellular protein adducts. GSH S-transferases (GST) help mitigate adduct formation by glutathione (GSH) conjugation. Here, we varied GSH levels using buthionine sulfoximine (BSO) and BaP pretreatments to deplete or augment GSH, respectively, to study adduct formation and metabolism at 4 µM 3 H-BaP over 24–48hr. An inverse relationship was observed between GSH levels and nuclear protein and DNA adducts. Time course experiments showed extracellular protein adducts, identified primarily as bovine serum albumin and α1-AT (α-1-antitrypsin) in culture medium, were 5–10 times greater than cellular protein adducts and comprised 8–9% of total metabolized 3 H-BaP. However, specific adduct binding (adducts/mg protein) in cells was much greater than for extracellular protein, likely from their intracellular proximity to CYP-mediated metabolism to BaP reactive metabolites. Proportions of 3 H-BaP hydroxylated and conjugated metabolites in BSO and BaP pretreated cells were not greatly altered from DMSO control after 24 hr. Bioinformatic analysis of T47D cell gene expression indicated CYP1B1 and CYP1A1 were primary enzymes for BaP bioactivation. We surmised reactive BaP metabolites that escaped conjugation reactions were sufficiently stable to migrate into the extracellular space. These results suggest BaP reactive metabolites like BPDE (BaP-diol-epoxide) can easily translocate across cell membranes despite robust conjugation systems and ready supplies of essential co-substrates for sulfate or GSH conjugations. The implications in vivo are that BaP reactive metabolites can enter adjacent epithelia and some fraction could result in DNA binding and somatic mutations in cancer susceptibility genes over time. The relationship continues to grow between PAH exposure and pollution, and many malignancies including breast cancers.

Establishing foundations: Designing a long-term experiment to evaluate whether nestboxes assist population recovery of an endangered species after fire

The loss of hollow-bearing trees drives population declines of hollow-dependent species. Disturbances such as wildfire can exacerbate these declines. Artificial structures, like nestboxes, are a commonly used management tool that attempt to offset hollow loss. However, the effectiveness of nestboxes as a conservation strategy is rarely tested within an experimental framework. The endangered southern greater glider ( Petauroides volans) is an obligate hollow-dependent arboreal marsupial that is highly sensitive to wildfire. Southern greater glider populations experienced high mortality and habitat degradation following the 2019/2020 megafires in south-eastern Australia. We established a long-term, landscape-scale experiment to test whether purpose-built nestboxes could assist the post-fire population recovery of the southern greater glider. We installed a total of 234 nestboxes at sites in East Gippsland (north-eastern Victoria) and Tallaganda (southern New South Wales). We matched nestbox sites to control sites. We undertook spotlighting surveys in both study areas and installed camera traps at a subset of nestboxes. We observed southern greater gliders using nestboxes in both regions, with substantially more observations in Tallaganda. These early results did not indicate a significant difference in the relative abundance of southern greater gliders between nestbox and control sites. In Tallaganda, we found more southern greater gliders in areas of lower fire severity. The longer-term outcomes of our study will inform the use of nestboxes as a tool to assist in the recovery of southern greater gliders following disturbance.

Experimental Evidence for Radical-Polar Crossover in Competition with, Rather Than Preceding, Alkene Formation by Microbial Ethylene-Forming Enzyme

Agronomic performance of cocoa production type systems in Colombia

Socio-economic and livelihood conditions influence the design of cocoa-based agroforestry systems (AFS), as they determine the selection of accompanying species and the overall productivity of the system. These arrangements contribute to income diversification, enhanced food security and increased resilience to climate-related impacts. However, achieving these benefits depends to a large extent on the capabilities of rural households, which are shaped by their human, social, cultural, political, financial, natural, and infrastructural assets. This study analyzes the incidence of rural household type, according to livelihood strategies on the agronomic performance and co-product generation of cocoa crops established in agroforestry systems, in the departments of Caquetá, Huila and Meta in Colombia. Capital endowments for cocoa production, as well as the intensity and frequency of shade canopy species associated with cocoa, were determined in 83 rural households. Then, 112 sampling plots of 1000 m 2 were established, where 20 variables of information on floristic composition, forest structure of the AFS, state of pest attack and diseases, and cocoa bean production were taken. It was found that the agroforestry characteristics of the cocoa crop and its production differed between rural household types and departments. A total of 176 species associated with cocoa were found, but only 89 were recognized by the farmers. These species were grouped into 17 uses, the most frequent being self-consumption, shade, wood, and sale (for human food). The livelihood strategy and assets for cocoa production had a high impact on the agronomic performance of the crop. Households with more experience, technology, knowledge and dedication to the crop obtained higher cocoa bean yields. These results affirm that the management and efficiency of cocoa-based AFS depend on the articulation of social processes and the design of the AFS.

Acoustic analysis of bottlenose dolphin vocalizations for behavioral classification in controlled settings

Understanding how bottlenose dolphins adjust their vocal behavior in response to daily routines can provide insights into social communication and welfare assessment in managed care environments. This study presents a detailed analysis of bottlenose dolphin ( Tursiops truncatus ) vocal behavior in relation to different daily activities within a controlled environment at Oltremare Marine Park (Riccione, Italy). 24 hours of continuous acoustic recordings were collected from seven dolphins during a typical day at the marine park, including training, feeding, playing, and unstructured activities. Signals were analyzed to quantify the variations in type and number of vocalizations in relation to dolphin activity. 3,111 whistles were manually extracted and stored as both normalized audio files and high-resolution spectrograms. Additionally, an automated algorithm identified 1,277 pulsed vocalizations, classified into echolocation click trains, burst-pulse sounds, and feeding buzzes, using signal-to-noise ratio (SNR) and inter-click interval criteria. Results revealed a significant increase in vocalization rates during structured activities compared to unstructured periods ( p  < 0.001). This trend was consistently observed across all four vocalization types. Notably, play sessions elicited the highest rates of pulsed vocalizations ( p  < 0.01), suggesting enhanced social and exploratory behaviors, i.e., interactions with conspecifics as well as curiosity-driven engagement with the environment. To test dataset reliability and usability, signal quality was analyzed by evaluating SNR. To support future research in marine mammal bioacoustics, behavioral ecology, and Artificial-Intelligence-based acoustic monitoring, the full annotated dataset was released as an open-access resource.