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Non-Gaussian statistics of the order parameter across a phase transition
Parametric study of electrohydrodynamic flow and heat transfer in a wind tunnel using thermochromic liquid crystals and smoke tracing
Daily briefing: Can the world finally eradicate polio?
Mechanical performance and water penetration resistance of two-stage concrete incorporating recycled aggregates from demolition waste
Abstract This study evaluates the mechanical and durability performance of sustainable two-stage concrete incorporating recycled fine and coarse aggregates obtained from building demolition waste. Four two-stage concrete mixtures were produced: NN with natural coarse and fine aggregates, RR with recycled coarse and fine aggregates, NM with natural coarse aggregate and mixed fine aggregate, and RM with recycled coarse aggregate and mixed fine aggregate. The mixed fine aggregate consisted of 50% natural sand and 50% recycled sand by mass. A conventional concrete mixture was also prepared as an additional reference. The experimental program included grout flexural and compressive strength, concrete compressive strength, ultrasonic pulse velocity, X-ray-based pore structure assessment, and water penetration under pressure. The results showed that recycled fine aggregate can be used effectively in grout production under the investigated conditions. The recycled sand grout reached a 90-day compressive strength of 49.25 MPa, slightly higher than the natural sand grout, although its flexural-strength response was lower and more variable. The fully recycled RR mixture achieved a 28-day compressive strength of 39.40 MPa, corresponding to 94.8% of the natural aggregate reference mixture. X-ray analysis showed that RR had a relatively low total air content of 0.82%, which supported its mechanical performance. RR also showed the lowest mean water penetration depth, 50.7 mm; however, this result was highly variable and should be interpreted as a mixture-specific observation governed by grout filling, aggregate packing, pore connectivity, and interface continuity rather than as a general improvement caused by recycled aggregates. Overall, the findings indicate that demolition-waste-derived recycled aggregates can be incorporated into two-stage concrete when aggregate quality, grading, grout rheology, and curing conditions are carefully controlled.
Human embryo metabolomic profiling under constant 5% vs physiological 8%–5%–2% oxygen: a preliminary prospective sibling-embryo study
Abstract Oxygen concentration declines from 5–8% in the fallopian tube to ~ 2% in the uterine cavity. However, clinical studies investigating ultra-low O₂ concentrations (2–3%) during human embryo culture have reported conflicting developmental outcomes. Whether these developmental differences are accompanied by metabolic adaptation in human embryos remains unknown. In this preliminary prospective sibling-split oocyte study, 111 embryos from 13 patients were cultured under constant 5% O₂ or a physiological 8%–5%–2% O₂ gradient. Spent culture media (n = 222) were analysed by nuclear magnetic resonance spectroscopy and high-performance liquid chromatography–tandem mass spectrometry against matched incubated control media. Spent-media analyses confirmed embryo-derived metabolic activity, characterized by pyruvate and glutamic acid depletion together with alanine and glutamine secretion. Neither patient-level analyses nor embryo-level linear mixed-effects models identified statistically significant metabolomic differences between the two O₂ culture conditions, whereas metabolite-turnover patterns showed significant inter-patient variability. Blastocyst-forming embryos exhibited lower total amino acid turnover than arrested embryos in cleavage-stage media (P = 0.037), whereas a similar trend in blastocyst-stage media was not significant (P = 0.106). These findings suggest that patient-specific and developmental factors contribute to embryo metabolic variability, while subtle O₂-associated metabolic effects cannot be excluded. Given the limited sample size, these findings are preliminary and hypothesis-generating.
Cetaceans from low-latitude oceanic waters rely on mesopelagic prey
Abstract The mesopelagic zone increasingly attracts the interest of commercial fisheries due to its large fish abundance and the growing worldwide demand for food. Many mesopelagic species serve as an important food source for many top predators but the extent to which these predators rely on mesopelagic prey remain poorly understood, especially in oligotrophic open ocean ecosystems. The Azores archipelago is surrounded by numerous seamounts and is subject to a dynamic oceanography, creating particularly attractive conditions for many top predators, including cetaceans. Using stable isotope mixing models (MixSIAR), we estimated diet proportions of seven species of cetaceans belonging to various trophic guilds. Overall, mesopelagic prey are key contributors to the diet of cetaceans. We find that Balaenoptera borealis , B. musculus and B. physalus consume mostly (> 70%) mesopelagic zooplankton (including copepods and krill). Mesopelagic fish and cephalopods contribute 20–35% to the diet of Delphinus delphis , Stenella frontalis and Tursiops truncatus , along with epipelagic and demersal fish. The diet of Physeter macrocephalus almost exclusively consists of mesopelagic cephalopods (> 94%). This study identifies mesopelagic fauna as a critical food resource for cetaceans in tropical and sub-tropical oceanic ecosystems, emphasizing the need for a precautionary approach and strict governance measures before developing commercial fisheries in the mesopelagic zone.
How volunteering links to college student well-being via friend support and self-efficacy
Abstract Well-being is an important part of positive psychology research, and the level of well-being of college students is related to their growth and development direction.This study examines the relationship between volunteering and well-being, with a focus on the mediating roles of friend support and self-efficacy. A total of 1149 students from a university in Shaanxi Province were selected as the research objects, and the self-report scale, friend support scale, general self-efficacy scale and volunteering scale were used to measure the data, and the data were statistically analyzed and analyzed by SPSS26.0. The results align with a model in which volunteering relates to well-being, friend support, and self-efficacy. Friend support and self-efficacy mediated the relationship between volunteering and well-being, both separately and sequentially (chain mediation). The chain mediating model is consistent with a theoretical pathway in which volunteering is associated with higher well-being via expanded social networks and stronger personal confidence. This study provides empirical evidence for universities to utilize volunteer programs that specifically foster friend support networks and self-efficacy training to maximize student well-being.
Structures and inhibition of the Crimean–Congo haemorrhagic fever virus polymerase
Exploring self-supervised deep sparse autoencoders for robust feature selection in radiomics analysis
Genetic background sets the trajectory of experimental cancer evolution
Abstract Human cancers are heterogeneous 1 . Dissecting how germline genetic variation and environmental factors shape tumour evolution using human datasets is limited by inherent diversity in genetic backgrounds 2 and environmental exposures 3–5 . Here, to overcome these limitations, we re-ran early tumour evolution hundreds of times in diverged inbred mouse strains, generating matched histology and whole-genome and transcriptome sequences. The sex, environment and carcinogenic exposures were all controlled, and the study design allowed us to capture genetic variation comparable with that observed across human populations while exploiting the nested hierarchical structure of strain–litter–animal–tumour relationships. Our analyses reveal that epistatic interactions between genetic background and acquired somatic mutations result in population-specific disease progression, including choice of driver mutations, occurrence of whole-genome duplication and subclonal selection dynamics that mirror both cancer susceptibility and tumour growth rate. Even modest genetic divergence, comparable with that found across human ancestry groups, can strikingly alter selection pressures during cancer development to shape both cancer risk and the trajectory of tumour evolution.
Rainfall isotopic variability in northern Central America driven by regionally-organized deep atmospheric convection and airmass rainout
Electronic-resonance enhanced molecule for perovskite solar cells
A crossover strategy integrated dung beetle optimization for global optimization problems and feature selection problems
Abstract Dung Beetle Optimization (DBO) is a recent swarm intelligence optimizer inspired by the rolling, dancing, foraging, breeding, and stealing behaviors of dung beetles. Although DBO has shown promising search capability, it may suffer from diversity loss, ineffective inferior-solution utilization, and boundary-induced stagnation when solving complex optimization problems. To address these issues, this paper proposes a Crossover Strategy Integrated Dung Beetle Optimization algorithm, named CSIDBO. The proposed method incorporates three mechanisms: a horizontal crossover strategy for dimension-level information exchange, a precise elimination mechanism for replacing low-quality individuals, and a global-best-guided boundary handling strategy for correcting infeasible solutions. Moreover, a transfer-function-based binary version of CSIDBO is developed for wrapper feature selection. The performance of CSIDBO is evaluated on CEC2017, CEC2020, and CEC2022 benchmark functions and sixteen feature selection datasets. Comparative experiments, ablation studies, convergence curves, exploration–exploitation analysis, runtime comparison, and statistical tests are conducted to provide a comprehensive evaluation. Experimental results show that CSIDBO achieves competitive optimization accuracy and feature selection performance compared with classical algorithms and recent DBO variants. Nevertheless, the results also indicate that CSIDBO is not universally optimal on all functions, and its additional operators introduce extra function evaluations and runtime overhead. These limitations are discussed to provide a balanced assessment of the proposed method.