Browse Articles

Characterization of spatial and temporal variations of CO2 concentration on tropical Island and analysis of influencing factors

Abstract In this study, the spatial and temporal variations and distribution characteristics of the carbon dioxide (CO 2 ) concentration on Hainan Island are analyzed using GOSAT L3 data from 2011 to 2024, and the effects of various factors impacting the CO 2 concentration on Hainan Island are discussed. The results indicate that from 2011 to 2024, the CO 2 concentration on Hainan Island showed an increasing trend, with a fast growth rate in the early period and a slow growth rate in recent years with the implementation of the dual-carbon strategy. The spatial distribution is affected by anthropogenic activities, topography, vegetation and solar radiation, and the overall CO 2 concentration pattern is high in the north and low in the south. Human activities are the most important source of carbon on Hainan Island, vegetation is the most important carbon sink, and elements such as surface temperature, precipitation, and total solar radiation play roles in suppressing CO 2 . The CO 2 concentration on Hainan Island is expected to continue to increase at a slow rate and may display a decreasing trend in the future.

Circadian rhythm profiles derived from accelerometer measures of the sleep-wake cycle in two cohort studies

Abstract Accelerometers allow objective measures of dimensions (rest-activity rhythm (RAR), daytime activity, sleep, and chronotype) of the bio-behavioural manifestation of circadian rhythm (CR) using multiple metrics in large-scale studies. These dimensions are rarely examined together due to methodological challenges of using correlated data. To address this challenge, we propose a two-step approach consisting of data reduction of CR metrics using principal component analyses, followed by k-means clustering to identify groups of individuals with a similar profile using data from the Whitehall II (N = 3,991, mean age=69.4years) and UK Biobank (N = 54,995, mean age=67.5years) cohort studies. Our analyses identified nine CR clusters: two presented extreme (most robust/poorest) RAR and (highest/lowest) daytime activity, two robust RAR with opposite sleep profiles (longer and efficient/shorter and fragmented), one high-intensity physical activity, and four poor RAR (one characterised by late chronotype, two by low activity but opposite sleep profiles, and one by restless (agitated) sleep). The participants in these nine clusters differed on sociodemographic, behavioural and health-related factors. Findings were similar in these two independent cohort studies, highlighting the validity of our approach. Most previous studies have used only the RAR dimension of circadian rhythm, and here we show that this might be an oversimplification as demonstrated by nine clusters characterised by combinations of RAR, daytime activity, sleep, and chronotype. Our innovative approach demonstrates feasibility of using all dimensions to study the impact of circadian rhythm dysregulation on health.

Effect of a PEN-3 model-based educational intervention on cigarette smoking in Iranian patients with myocardial infarction

Feasibility study of hydrogen-ammonia synergistic combustion in scramjets across broad Mach ranges

Percolation effect induced significant changes in the complex permittivity and permeability of silver-epoxy nano-composites

One-step propylene purification from a quaternary mixture by a single physisorbent

Abstract One-step removal of multiple impurities implemented by adsorptive separation is an efficient and simple process to afford high purity products, but is hindered by the lack of advanced porous materials that could capture different types of molecules. Herein, a series of novel metal-organic frameworks ZU-921 to ZU-924 with cooperative binding environment of integrated aromaticity surface and fluorine/oxygen electronegative sites are designed, and ZU-921 is presented as the demonstration that solves the long-standing challenge in one-step propylene (C 3 H 6 ) purification from the C3 quaternary mixture. The selective recognition ability towards alkyne, allene, alkane than alkene implemented by ZU-921 is attributed to the optimal interaction contribution from polarizability and dipole/quadruple moments that is realized by the fine-tuned density of parallelly-distributed electronegative sites via ligand engineering strategy. Ultra-high purity (99.99%) C 3 H 6 could be directly obtained from the C3 quaternary mixture (C 3 H 4 /C 3 H 4 (PD)/C 3 H 8 /C 3 H 6 1 v/1 v/3 v/95 v) with the productivity of 17.27 L/kg derived from the 10-times scale-up column (1.0 cm × 50 cm) breakthrough experiment. This work not only presents a common strategy in advanced adsorbents design for multiple impurities capture but also provides an energy-efficient alternative for C 3 H 6 purification.

Optimized YOLOv11m for real-time high-speed railway catenary defect detection

Abstract Real-time defect detection of high-speed railway catenary components remains challenging due to the prevalence of small-sized parts (e.g., cotter pins, fasteners) and the computational constraints of deployment platforms. While existing YOLO-based models offer a balance between speed and accuracy, they often struggle with small object detection and suffer from high computational costs. To address these limitations, this paper proposes an optimized YOLOv11m model, termed MSIM-YOLOv11m, which integrates three novel modules: large separable kernel attention (LSKA) for enhanced feature extraction, bidirectional feature pyramid network (BiFPN) for efficient multi-scale fusion, and adaptive kernel convolution (AKConv) for flexible feature learning. Experimental results on a dedicated catenary dataset show that the proposed model achieves a mAP50-95 of 78.3% and a small-target AP of 64.7%, while reducing computational cost by 50.5% compared to YOLOv9m. The model provides a lightweight and accurate solution suitable for real-time inspection applications.The code has been uploaded to https://github.com/1748125472/MSIM-Yolov11m/tree/master .

Interplay between climate and childhood mixing can explain a sudden shift in RSV seasonality in Japan

A comprehensive assessment of Ghana’s energy security dimensions and environmental sustainability in a multi-indices analysis

Abstract This study presents a comprehensive evaluation of Ghana’s energy security and environmental sustainability using a multi-indices approach. Focusing on five key indicators: the Herfindahl–Hirschman Index (HHI), Shannon–Wiener Index (H), Simpson Index (D), Adjusted Shannon–Wiener Neumann Index (SWNI), and Carbon Intensity Index (CI) are employed to assess the concentration, diversification, and dependency of Ghana’s energy sources alongside carbon emissions. The results indicate a highly concentrated energy portfolio, with petroleum products and biomass dominating the energy mix. The HHI score of 0.23 reflects moderate market concentration, while the Shannon–Wiener Index of 1.5 and Simpson Index of 4.3 highlight a relatively diverse but still imbalanced energy mix. The SWNI1 score of 0.37, accounting for political risk, reveals a vulnerability due to reliance on imported energy. Furthermore, the Carbon Intensity Index of 5.50 kt CO 2 per ktoe of energy consumed (2022) underscores significant carbon emissions, necessitating a sustainable energy transition. These findings emphasize the need to enhance domestic energy production, diversify energy sources, and adopt low-carbon technologies to improve Ghana’s energy security and environmental resilience.

Effects of an anti-lipogenic low-carbohydrate high polyunsaturated fat diet or a healthy Nordic diet versus usual care on liver fat and cardiometabolic disorders in type 2 diabetes or prediabetes: a randomized controlled trial (NAFLDiet)

Abstract Polyunsaturated fatty acids (PUFA) have been shown to reduce liver fat compared to saturated fat, but effects of a novel “anti-lipogenic” diet replacing carbohydrates with PUFA (LCPUFA) or a low-fat healthy Nordic diet (HND) rich in whole-grains are unknown. The objective of this study was to investigate the effects of these diets, as compared with usual care (UC), on liver fat (primary outcome) and related glycemic and lipid disorders after 12 months of intervention, in individuals with prediabetes or type 2 diabetes (T2D). A three-arm parallel ad libitum randomized trial was completed in December 2022 (NCT04527965). Outcome assessors and care providers were blinded to participants’ diets. Men and women (n=150) with prediabetes or T2D (55%) were randomized in a 1:1:1 allocation ratio, stratified by sex and T2D status, and were assessed at the Uppsala Academic hospital. General linear models were employed to estimate intention-to-treat effects. Liver fat was reduced after the LCPUFA diet (n=54) and the HND (n=51) when compared to UC (n=43); -1.46% (95% CI: -2.42, -0.51)) and -1.76 % (95% CI: -2.96, -0.57), respectively. No difference in liver fat between LCPUFA and HND was observed. Body weight and HbA1c decreased more in the HND versus the other diets, whereas no differences were observed between LCPUFA and UC. LDL-cholesterol was reduced to a similar extent during the HND and LCPUFA diet, compared to UC, whereas only HND reduced triglycerides, inflammation and liver enzymes. In total, n=4 serious adverse events occurred, distributed among groups. An ad libitum mainly plant-based LCPUFA diet and HND similarly reduced liver fat and LDL-cholesterol, compared with UC. Even without intentional energy restriction, the HND further improved body weight, glycemic control, liver biochemistry, triglycerides, and inflammation, suggesting a HND as a clinically feasible diet for the management of T2D and metabolic dysfunction-associated steatotic liver disease (MASLD).

A new 37- level inverter with reduced switches for renewable energy applications

Abstract Multilevel inverters (MLIs) are now crucial in producing high-quality output waveforms due to their modularity and efficiency. This paper presents a novel 37- level MLI topology with a reduced number of switches and sources. The proposed design offers several advantages, including lower total harmonic distortion (THD) of 1.21% in hardware and 0.8% in simulation, high efficiency of 93.26%, reduced total standing voltage of 18 V DC ), and an improved component-per-level ratio compared to existing MLIs. The inverter performance is validated using MATLAB/Simulink and a laboratory prototype controlled by a dSPACE system under different load conditions. Results confirm that the proposed inverter maintains stable operation during dynamic load changes and provides a cost-effective, compact, and reliable solution for renewable energy and electric vehicle applications.

Flexible read-aware genotype imputation from sequence using biobank sized reference panels

Abstract Inexpensive and accurate genotyping methods are essential to modern genomics and health risk prediction. Here we introduce QUILT2, a scalable and read-aware imputation method that can efficiently use biobank scale haplotype reference panels. This allows for fast and accurate imputation using short reads, as well as long reads (e.g. Oxford Nanopore Technologies (ONT) 1X, r2 = 0.937 at common SNPs), linked-reads and ancient DNA. In addition, QUILT2 contains a methodological innovation that is designed to enable imputation of the maternal and fetal genome using cell free non-invasive prenatal testing (NIPT) data. Using a UK Biobank reference panel and simulated NIPT data, we see accurate imputation of the mother (0.25X, r2 = 0.966, common SNPs) and modest imputation of the fetus (0.25X, r2 = 0.465, fetal fraction of 10%) at low coverage, with fetal imputation accuracy rising with coverage (4.0X, fetal r2 = 0.894). We show using simulated data that this could enable both GWAS and PRS for the mother and fetus, which could create clinical opportunities, and if phenotypes can be collected alongside clinical NIPT, the potential for large GWAS.

Pomegranate peel as a natural reducing agent in leaching of manganese concentrate

Gain engineering and atom lasing in a topological edge state in synthetic dimensions

Abstract Recent advances in quantum technology have highlighted the importance of controlling quantum states, especially in open quantum systems, where the system interacts with the environment. Non-Hermitian quantum mechanics describes these systems. Photonic systems are a key platform for studying non-Hermitian quantum mechanics owing to their ability to engineer gain and loss. Ultracold atomic gases also have been used to study non-Hermitian quantum mechanics; however, unlike photonics, gain control is challenging, limiting exploration to control of loss. In this paper, we report engineering of effective gain through evaporative cooling of judiciously selected initial thermal atoms, leading to Bose–Einstein condensation (BEC) in the excited eigenstates of a synthetic lattice. We achieve BEC formation in a topological edge state of the Su–Schrieffer–Heeger lattice in the synthetic hyperfine lattice, akin to atomic laser oscillations at a topological edge mode, that is, a topological atom laser.

Influence of Bʹ-site vacancy on hydrogen storage, structural, elastic, thermodynamic and optoelectronic attributes of potassium based double perovskite K2LiAlH6hydride for green energy applications

Correlation stabilized anomalous Hall crystal in bilayer graphene

Exploring gut microbiota alterations and their associations with clinical symptoms in fibromyalgia

Coupling a single spin to the motion of a carbon nanotube

Abstract The ability to couple a solitary spin to high-frequency motion is a crucial advancement for a range of applications, including quantum sensing, intermediate and long-distance spin-spin coupling, and quantum information processing. Although proposed theoretically over a decade ago, experimental demonstrations have remained elusive. Here we report the observation of spin-mechanical coupling in a carbon nanotube device. We demonstrate this coupling in two configurations: off-resonant, with spin and mechanics excited by separate tones, and resonant, driven by a single tone. The coupling manifests as a shift and broadening of the electric dipole spin resonance (EDSR), respectively. Our theoretical model, which accounts for the tensor character of the coupling and mechanical non-linearity, reproduces the data with very good agreement. Our results demonstrate a previously unobserved spin-mechanical coupling, offering versatile tools for exploring macroscopic quantum phenomena, quantum thermodynamics, and quantum simulation.

Clinical–radiological profile and risk factors for early mortality in preterm neonates with respiratory distress syndrome in Hoima, Western Uganda

Abstract Respiratory distress syndrome (RDS) is the leading cause of respiratory failure and neonatal mortality, particularly in preterm infants. Despite global advances in neonatal care, RDS remains a significant problem in low-resource settings such as Uganda, where limited evidence exists on clinical profiles, mortality, and associated risk factors. Although these advances have greatly reduced mortality in high-income settings, their limited availability in Uganda contributes to the continued high burden of RDS-related deaths. To determine the clinical–radiological profile, early mortality, and risk factors for mortality among preterm neonates admitted with RDS at Hoima Regional Referral Hospital. A prospective cohort study was conducted among 150 preterm neonates with clinically and radiologically confirmed RDS. Data on sociodemographic, clinical, and obstetric characteristics were collected using structured questionnaires and chest X-rays. Participants were followed for seven days to determine outcomes. Descriptive statistics summarized baseline characteristics, while Poisson regression identified independent predictors of mortality. Of the 150 neonates, 62.7% were male and 70.7% were born before 32 weeks of gestation. Tachypnea (84.7%) and intercostal/subcostal retractions (71.3%) were the most frequent clinical features, while ground-glass patterns were the predominant radiological finding. Twenty-nine neonates died within the first seven days, giving an early mortality rate of 19.3%. Independent predictors of mortality were delayed presentation beyond six hours of life (aRR = 1.72, 95% CI: 1.43–2.07, p  < 0.001) and birth weight < 1.5 kg (aRR = 1.12, 95% CI: 1.02–1.22, p  = 0.015). RDS contributes substantially to early neonatal mortality in Uganda. Prompt recognition, early referral, and improved neonatal care—particularly for very low birth weight infants—are critical to improving outcomes. Although not directly measured in this study, improving access to antenatal corticosteroids and respiratory support—well-established interventions—remains essential for broader improvement of RDS outcomes.

Cost-effective non-additive GWAS across 2329 diseases in 500,349 individuals