Browse Articles

A qualitative study of stakeholder perspectives on the challenges of the rapid expansion of medical student enrollment in Iran

Iron deficiency strategy toward single-phase high-entropy M-type ferrites for broadband millimeter-wave absorption with low thickness

Hypertension and associated factors among HIV/AIDS patients on highly active anti-retroviral therapy (HAART)

Neural and computational mechanisms of effort under the pressure of a deadline

Abstract Deadlines fundamentally shape motivation. Research examining effort-based choices finds effort is an avoided cost. However, this overlooks how making progress on longer-term goals to be reached before deadlines motivate people to exert high effort for little immediate reward. Here, we test a framework where motivation depends on deadline pressure (work remaining / time remaining). Across four studies we use computational modelling examining decisions when physical effort makes progress on goals with deadlines. In support of the hypotheses, deadline pressure significantly impacts decision-making, shifting people from avoiding effort, to seeking the progress it makes. Using ultra-high-field fMRI, we show that functionally connected putamen and midcingulate cortex sub-regions process and update estimates of deadline pressure, with distinct anterior cingulate and putamen sub-regions processing effort both when it is being avoided or sought. These results reveal the neurocomputational mechanisms for how deadline pressure shapes motivation, and keep us on track with goals.

Genomic evidence that Enterobacter strain MG-EB028 and Enterobacter nematophilus strain 93 form a lineage distinct from Enterobacter nematophilus sensu stricto

Metal pre-intercalation promotes water-mediated proton-coupled electron transfer in layered δ-MnO2 for aqueous pseudocapacitive energy storage

Abstract The charge storage capacitance of δ-MnO 2 -based pseudocapacitors stems from a combination of bulk cation intercalation/deintercalation and surface proton chemisorption/desorption. Here, we investigate the mechanistic origins of the enhanced capacitance in δ-MnO 2 with pre-intercalated Cu 2+ . To this end, we synthesize Au-core/δ-MnO 2 -shell nanostructures with and without Cu 2+ pre-intercalation, enabling real-time in situ spectroscopic monitoring of structure-function relationships during electrochemical cycling. Transition metal pre-intercalation preserves interlayer-confined water, which in turn supports proton-coupled charge storage via the reversible reaction of MnO 2  + H 2 O + e - ⇌ MnOOH + OH - . This confined water forms a hydrogen-bonded network that lowers the energy barrier for proton transport within the interlayer space. Similar mechanistic transition is also evident in δ-MnO 2 systems pre-intercalated with other transition metal ions, such as Co 2+ and Mg 2+ . By tuning the MnO 2 shell thickness, we decouple the relative contributions of proton- and cation-driven processes, revealing that proton intercalation delivers a markedly higher specific capacitance than cation intercalation. Electrolyte-dependent studies further reveal that Cu 2+ pre-intercalation promotes OH - transport within the interlayer space while preserving proton accessibility at active sites. These findings suggest that proton-coupled transport may offer further increases in charge storage performance in pseudocapacitors.

Tempol ameliorates STZ-induced T1DM potentially via enhancing AMPK signaling, suppressing pro-apoptotic activity, promoting progenitor cells recruitment, and restoring glucose transporters level

Anti-malaria antibody engineering broadens recognition motifs and reveals new homotypic interactions that enhance protective breadth

Integration of a clinical survival model into the KM-plotter to identify high-risk populations in breast cancer

Abstract We aimed to establish clinically meaningful survival models in breast adenocarcinoma to support pharmacological research and guide therapy development. Using data from over 1.1 million patients in the SEER database, we performed univariate and multivariate Cox survival analyses on infiltrating ductal carcinoma cases stratified by pathological and demographic variables. By quantifying hazard ratios and Kaplan–Meier survival estimates across clinical subgroups, we identified patient cohorts with significantly reduced breast-cancer-specific survival. We further approximated the life-years lost in each subgroup to assess the cumulative survival burden and to prioritize cohorts for therapeutic intervention. Significant survival differences were observed across molecular subtypes and pathological categories, with ER-negative, triple-negative, node-positive, high-grade, advanced-stage, and larger tumors showing markedly reduced 60-month survival. For instance, survival declined from 96% in Stage I to 33% in Stage IV disease, from 98% in Grade 1 to 80% in Grade 4 tumors, and from 95% in tumors 10–19.9 mm to 51% in those ≥ 100 mm. Receptor-negative, high-grade tumors, despite their lower prevalence, account for a disproportionately large fraction of total life-years lost. To facilitate reproducibility and exploratory analyses, we integrated these clinical survival models into an upgraded version of the Kaplan–Meier plotter, which now supports user-defined cohort analysis based on clinicopathological variables. In summary, here we provide a large-scale, clinically grounded survival framework to identify and optimize target cohorts for pharmacology developments in breast cancer.

Hyperdimensional in-memory computing with analogue memristive crossbar arrays

Dual-band dual-beam millimeter-wave antenna using dual circular microstrip rings

Abstract The growing demand for high-capacity millimeter-wave (mmWave) communication systems requires compact, high-gain antennas that provide efficient spatial coverage while remaining simple to fabricate and integrate. This article presents a novel dual-band, dual-beam microstrip antenna based on a dual circular-ring radiator. Unlike existing designs, the proposed antenna achieves wide dual-band, dual-beam operation without vias, parasitic elements, or metamaterial loading, resulting in a compact, low-profile architecture that is straightforward to fabricate using standard printed circuit board (PCB) technology. Excitation of higher-order resonant modes, combined with optimization of the ring geometry and ground plane, produces symmetric dual-beam radiation in the quasi-E plane across two wide operating bands of 24.2–30 GHz and 32.5–43.5 GHz. Measured results agree closely with simulations, validating the antenna’s wide impedance bandwidth and stable radiation characteristics. The antenna generates dual beams at ± 40 $$^{\circ }$$ in the lower band and ± 24 $$^{\circ }$$ in the upper band, achieves a peak realized gain of 9 dBi at 38 GHz, and maintains gains exceeding 6 dBi across both bands. These characteristics make the proposed antenna a practical and cost-effective solution for next-generation indoor mmWave communication systems.

Challenges and achievements on the road to hepatitis elimination

Recovery and utilization of fluorescent carbon dots from slag-washing wastewater of waste incineration power plants for cell imaging

The OmniAge compendium of aging omic biomarkers links mitotic clocks to clonal hematopoiesis and causality

Nonsingular fast terminal sliding mode control based on super-twisting finite-time ESO for aerospace electro-hydraulic load simulators under large loads

Structural Basis of Amyloid Fibril Assembly by Plant Seed Storage Proteins

Clinical relevance of MRI-informed motor progression phenotypes in early Parkinson’s disease

Forests in protected areas worldwide face increased thermal pressure from urbanization

Abstract Protected areas (PAs), thermal refuges for biodiversity, are increasingly under pressure from urbanization. Gaps remain in how urbanization worldwide influences the thermal environment of PAs. Here, we quantify urban pressure on protected forests as a distance-weighted built-up intensity. The thermal impacts of urban pressure are assessed by comparing satellite-derived mean land surface temperature (LST) and thermal extremes inferred by the 90th-percentile maximum LST of protected forests within and beyond a 5-km buffer zone outside urban boundaries. We show that the global mean distance between urban areas and PAs has decreased by over one-third (12.82 km) since 1990, increasing urban pressure on protected forests by about 2.56%. Urbanization alters thermal environments by elevating LST, and the frequency and intensity of thermal extremes, with the highest impact on annual mean daily LST (0.63 °C) and intensity of thermal extremes (0.81 °C) in tropical protected forests. We highlight the need to integrate urban development and conservation planning to support biodiversity conservation and sustainable development.

Behavior of reinforced concrete two-way slabs reinforced with carbon FRP bars under flexural loads

Abstract This study presents an experimental, numerical, and analytical investigation of the flexural behavior of two-way high-strength concrete (HSC) slabs reinforced with carbon fiber-reinforced polymer (CFRP) bars. Seven slabs with dimensions of 1500 mm × 1500 mm were tested, including one steel-reinforced reference slab and six CFRP-reinforced slabs with two thicknesses, 100 and 120 mm, and three CFRP reinforcement ratios. For the 100 mm slabs, increasing the CFRP reinforcement ratio increased the ultimate load by 13.8% and 24.3% relative to S100-CFRP1, while the corresponding increases for the 120 mm slabs were 31.1% and 48.0% relative to S120-CFRP1. Increasing the slab thickness from 100 to 120 mm enhanced the ultimate load by 27.7%, 47.2%, and 52.1% for the corresponding CFRP-reinforced specimens. A mechanically normalized comparison between the steel-reinforced reference slab and the CFRP-reinforced slab with the same nominal reinforcement ratio showed that the two specimens were not mechanically equivalent. The CFRP-reinforced slab had lower effective reinforcement stiffness but a higher strength-based mechanical reinforcement index, resulting in a higher ultimate load but lower deformation capacity. Crack observations confirmed flexural failure with more localized cracking in the CFRP-reinforced slabs. A nonlinear finite element model was developed in ABAQUS and validated against the experimental results, with an average ultimate-load prediction error of approximately 7.2%. Analytical predictions based on ECP 208–2019 and ACI 440.1R-15 showed average predicted-to-experimental ultimate-load ratios of 1.43 and 1.27, respectively, indicating that ACI 440.1R-15 provided closer estimates than ECP 208–2019 for the tested CFRP-reinforced slabs.

Skeletal muscle properties in long COVID and ME/CFS differ from those induced by bed rest

Abstract Patients with long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) suffer from post-exertional malaise. The accompanying physical inactivity may contribute to a lower aerobic capacity and may explain skeletal muscle adaptations in these patients. Here, we compare whole-body exercise responses and skeletal muscle adaptations after strict 60-day bed rest in healthy people with those in long COVID and ME/CFS patients, and healthy age- and sex-matched controls. Bed rest alters respiratory and cardiovascular responses to maximal exercise, which are dissimilar in patients. Bed rest causes muscle atrophy without altering fiber type. Both patient groups have more glycolytic fibers, and ME/CFS patients display type I-specific atrophy. Only after bed rest is oxidative phosphorylation capacity associated with maximal oxygen uptake. As skeletal muscle characteristics differ between patients and healthy individuals after bed rest, physical inactivity cannot solely explain the lower exercise capacity and skeletal muscle adaptations in long COVID and ME/CFS patients.