Search Results (1,551)

Researchers comparing countermovement (CMJ) and assisted countermovement (ACMJ) jumps reported conflicting findings on the landing impact force (LIF). This was likely due to differences in the landing strategies used. As the magnitude of LIF may have implications on neuromuscular adaptations, the purpose of this study was to compare the LIF between CMJ and ACMJ while adopting soft and stiff landing strategies. Thirteen resistance-trained athletes (sex: female = 5, male = 8, 26.4 ± 3.7 years, 68.4 ± 13.6 kg, 167 ± 5.1 cm) performed three CMJ and ACMJ each at 60%, 70%, 80% and 90% of bodyweight with instructions to either land soft or stiff on a force plate. Repetitions were separated by 30 s and conditions by 3 min. Resistance bands were used to induce the required weight during ACMJ. Data obtained regarding the average of the two closest trials based on jump height was analysed. Jump height significantly increased with increasing assistance during ACMJ for both landing conditions (p < 0.001). Propulsion duration (PD) was significantly shorter with increasing assistance during ACMJ for both landing conditions (p < 0.001). Peak and mean propulsion force significantly decreased with increasing assistance during ACMJ for both landing conditions (p < 0.001 and p < 0.001, respectively). The LIF was significantly greater with increasing assistance during ACMJ in the stiff-landing condition only (p < 0.001). Greater assistance allowed participants to jump higher while reducing PD. The higher LIF observed during stiff landing with greater assistance during ACMJ could be attributed to greater jump height and downward velocity during landing. Full article

A robust and stability-indicating Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) method was developed and validated for the quantitative determination of bexagliflozin and its related impurities in accordance with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH Q2(R1)) guidelines. Chromatographic separation was achieved on a C18 column using a mobile phase of methanol and ammonium acetate buffer (pH 4.2) in a 60:40 (v/v) ratio, with a flow rate of 1.0 mL·min⁻¹ and UV detection at 220 nm. The method was validated for linearity, sensitivity (LOD and LOQ), precision, robustness, and system suitability, all within acceptable limits for low-concentration analysis. Excellent linearity (r² > 0.999) and precision (%RSD 0.3–4.4%) confirmed its reliability for stability assessment. The assay was performed at 100 µg·mL⁻¹, where all validation parameters showed %RSD values ≤ 2%, demonstrating high precision and robustness. Forced degradation studies under acidic, basic, oxidative, photolytic, and thermal conditions revealed a major degradation product formed under acidic stress. This product was isolated and structurally characterized using LC–MS, ¹H NMR, and ¹³C NMR, and is reported here for the first time. The proposed RP-HPLC method proved to be specific, precise, and reliable for the determination of bexagliflozin and its related impurities, making it suitable for routine stability testing, quality control, and pharmaceutical development applications. Full article

The gut microbiota forms early in life and undergoes dynamic changes that are essential for host health and development. Although body condition is a key fitness-related trait and predictor of viability in many animal species, its association with gut microbiota, especially during early life stages in wild populations, remains poorly understood. In this study, we collected fecal samples and used 16S rRNA gene sequencing to investigate temporal shifts in gut microbiota of Japanese tits (Parus minor) across nestling stages (days 3, 6, 10, and 14 post-hatching, denoted as D3, D6, D10, and D14, respectively; n = 70, repeatedly sampled) and in adults (n = 25), and examined their association with nestling body condition. The results showed that nestlings harbored distinct microbial communities compared to adults, with the latter exhibiting higher relative abundances of Bacteroidota and Verrucomicrobiota (LMMs, p < 0.001 for both). LEfSe analysis identified Actinobacteriota as a biomarker for D14 nestlings and Bacteroidota for adults. Alpha diversity decreased from D3 to D14, with adults showing higher diversity than late-stage nestlings (D10–D14), but comparable diversity to early-stage nestlings (D3–D6). Beta diversity revealed clear separation between nestlings and adults, and within nestlings, early stages (D3–D6) differed significantly from D14. Nest effects also contributed to microbial structure. Time-lagged analyses showed that Firmicutes abundance at D6 positively predicted scaled mass index (SMI) at D10 (p = 0.002), whereas Proteobacteria negatively predicted SMI (p = 0.006). Overall, these findings highlight dynamic, stage-specific shifts in the gut microbiota of Japanese tits and suggest that microbial succession may influence nestling growth and physiological adaptation. Full article

Coccomyxa onubensis (C. onubensis) belongs to the extensive genus Coccomyxa, which inhabits ecosystems with high metal concentrations, generally at acidic pH. In this study, the feasibility of cultivating the acidotolerant microalga C. onubensis in raceway open ponds was investigated. Specific attention was paid to the production of lipids and carotenoids. C. onubensis was cultivated outdoors, under non-sterile conditions, in three separate ponds that differed in their nutrient concentrations and aeration rates. The results show that C. onubensis was able to grow steadily and free of photosynthetic contaminants throughout the cultivation period. The low pH of the media prevented non-extremophilic competitors from proliferating, thus allowing for the selective growth of C. onubensis. The highest productivity values for the biomass and targeted compounds were obtained in the culture supplemented with twice the amount of nutrients and aeration rate. These significant maximum productivity values were 0.223 mg of carotenoids·g⁻¹·d⁻¹, 0.139 mg of chlorophylls·g⁻¹·d⁻¹, and 0.031 g of biomass·L⁻¹·d⁻¹. A significant maximum lipid production of 9.87% in the dry biomass was reached, of which 49.92% corresponded to polyunsaturated fatty acids (PUFAs). Overall, this manuscript demonstrates that the production of acidic-habitat microalgae in open systems can be advantageous for microalgae-based production of carotenoids and PUFAs, while avoiding contamination by photosynthetic competitors. Full article

Sunflower stalks derived biochars were fabricated through sequential alkali/enzymatic pretreatment, carbonization, and chitosan modification, and were used as eco-friendly adsorbents for Cu (II) removal from wastewater. The effects of pH, temperature, adsorption time, and dosage of biochar on Cu (II) adsorption separation from the model solution were comprehensively investigated. Results demonstrated that the chitosan treatment of biochar, obtained from the carbonization of pretreated sunflower straw, significantly altered the porous structure and surface functional groups of the material. Specifically, the biochar carbonized at 500 °C and subsequently treated with chitosan exhibited optimal adsorption performance at pH 5 and 35 °C. Under these conditions, a maximum Cu(II) adsorption capacity of 268.2 mg g⁻¹ (of biochar) was realized. Further analysis indicated the Cu(II) adsorption generally followed pseudo-second-order kinetics (R² > 0.99). Langmuir isotherm modeling revealed that the biochar modified by NaOH and chitosan displayed the highest correlation coefficient (R² > 0.99), suggesting predominantly homogeneous monolayer adsorption. Therefore, the novel low-cost and environmentally friendly biomass-derived adsorbents demonstrate significant potential for effective treatment of the heavy metal-contaminated wastewater. Full article

Current CO₂-based energy storage systems still face several unsolved technical challenges, including strong thermal destruction between the multi-stage compression and expansion processes, significant exergy destruction in heat exchange units, limited utilization of low-grade heat, and the lack of an integrated comprehensive performance framework capable of simultaneously evaluating thermodynamic, economic, and environmental performance. Although previous studies have explored various compressed CO₂ energy storage (CCES) configurations and CCES–Organic Rankine Cycle (ORC) couplings, most works treat the two subsystems separately, neglect interactions between the heat exchange loops, or overlook the combined effects of exergy losses, cost trade-offs, and CO₂-emission reduction. These gaps hinder the identification of optimal operating conditions and limit the system-level understanding needed for practical application. To address these challenges, this study proposes an innovative system that integrates a multi-stage CCES system with ORC. The system introduces ethylene glycol as a dual thermal carrier, coupling waste-heat recovery in the CCES with low-temperature energy utilization in the ORC, while liquefied natural gas (LNG) provides cold energy to improve cycle efficiency. A comprehensive 4E (energy, exergy, economic, and environmental) assessment framework is developed, incorporating thermodynamic modeling, exergy destruction analysis, CEPCI-based cost estimation, and environmental metrics including primary energy saved (PES) and CO₂ emission reduction. Sensitivity analyses on the high-pressure tank (HPT) pressure, heat exchanger pinch temperature difference, and pre-expansion pressure of propane (P₃₀) reveal strong nonlinear effects on system performance. A multi-objective optimization combining NSGA-II and TOPSIS identifies the optimal operating condition, achieving 69.6% system exergy efficiency, a 2.07-year payback period, and 1087.3 kWh of primary energy savings. The ORC subsystem attains 49.02% thermal and 62.27% exergy efficiency, demonstrating synergistic effect between the CCES and ORC. The results highlight the proposed CCES–ORC system as a technically and economically feasible approach for high-efficiency, low-carbon energy storage and conversion. Full article

The development of oil–water separation materials that combine high separation efficiency, robust mechanical properties, and environmental degradability remains a significant challenge. This study presents a novel degradable and superhydrophobic porous material fabricated via a multi-step process. A porous foam was first synthesized from degradable poly(ε-caprolactone-co-2-ethylhexyl acrylate) using a high internal phase emulsion templating technique. The foam was subsequently modified through in situ silica (SiO₂) deposition via a sol–gel process, followed by grafting with hydrophobic hexadecyltrimethoxysilane (HDTMS) to produce the final oil–water separation porous materials. Various characterization results showed that the optimized material featured a hierarchical pore structure in micro scales and the porosity of the foam remained ~90% even after the 2-step modification. Mechanical tests indicate that the modified material exhibited significantly enhanced compressive strength and the water contact angle measurements revealed a superhydrophobic surface with a value of approximately 156°. The prepared material demonstrated excellent oil/water separation performance with notable absorption capacities ranging from 4.11 to 4.90 g/g for oils with different viscosity. Additionally, the porous material exhibited exceptional cyclic stability, maintaining over 90% absorption capacity after 10 absorption-desorption cycles. Moreover, the prepared material achieved a mass loss of approximately 30% within the first 3 days under alkaline hydrolysis conditions (pH 12, 25 °C), which further escalated to ~70% degradation within four weeks. The current work establishes a feasible strategy for developing sustainable, high-performance oil–water separation materials through rational structural design and surface engineering. Full article

In recent years, high-entropy materials (HEMs) have emerged as a promising multifunctional material system, garnering significant interest in the field of photocatalysis due to their tunable microstructures, diverse compositions, and unique electronic properties. Owing to their multi-element synergistic effects and abundant active sites, high-entropy photocatalysts enable precise regulation over the separation efficiency of photo-generated charge carriers and surface reaction pathways, thereby significantly enhancing photocatalytic activity and selectivity. The high configurational entropy of these materials also imparts exceptional structural stability, allowing the catalysts to maintain long-term durability under harsh conditions, such as intense light irradiation, extreme pH levels, or redox environments. This provides a potential alternative to common issues faced by traditional photocatalysts, such as rapid deactivation and short lifespans. This review highlights recent advancements in the preparations and applications of HEMs in various photocatalytic processes, including the degradation of organic pollutants, hydrogen production, CO₂ reduction and methanation, H₂O₂ production, and N₂ fixation. The emergence of high-entropy photocatalysts has paved the way for new opportunities in environmental remediation and energy conversion. Full article

This study explores the complex psychological mechanisms linking career adaptability to work engagement under AI-driven workplaces. We examine the mediating role of job satisfaction and investigate a key hypothesis: that the adaptive benefits of AI self-efficacy are dampened by the emotional costs associated with AI anxiety. A dual-analytical approach was employed on a sample of 311 young Chinese workers. First, we conducted conditional process analysis using PROCESS Model 11 with 5000 bootstrapped samples to test for conditional indirect effects. Second, we utilized latent variable structural equation modeling for robust validation at the structural level. Analyses were adjusted for demographic and occupational covariates. As a result, the initial PROCESS analysis revealed that the key triple interaction (career adaptability × AI self-efficacy × AI anxiety) was statistically significant in all three test models (e.g., Model 1: b = −0.3509, p = 0.0075). Further analysis showed that the positive moderating effect of AI self-efficacy was contingent on AI anxiety; it was strongest at low AI anxiety and weakest (but still significant) at high AI anxiety. However, the more robust latent variable SEM (CMIN/DF = 1.569, CFI = 0.939, RMSEA = 0.043) revealed a critical separation of effects. The indirect effect operates exclusively through intrinsic job satisfaction, which was significantly predicted by the unified second-order career adaptability factor (b = 1.361, BCa 95% CI [1.023, 1.967]). The path from extrinsic satisfaction to WE was non-significant (b = 0.107, BCa 95% CI [−0.030, 0.250]). Furthermore, the SEM isolated a significant direct positive effect from the unified career adaptability factor to work engagement (b = 0.715, BCa 95% CI [0.385, 1.396]). This study highlights that the adaptability–engagement link operates via two distinct mechanisms: an indirect pathway from a unified career adaptability construct through intrinsic job satisfaction, and a direct pathway from career adaptability to work engagement. While PROCESS analysis suggests that anxiety dampens confidence, our SEM results clarify that this should be interpreted cautiously, as the mediation pathway via extrinsic satisfaction is not robust to measurement error. These findings underscore a multi-faceted mandate for organizations: leaders must not only manage AI anxiety but also foster holistic career adaptability to enhance intrinsic job quality and build direct engagement. Full article

Introduction: Red spinach powder (RSP) contains high amounts of inorganic nitrate/nitrite (NO₃/NO₂), which has been suggested to alter vascular activity, cognitive processing, and sprint exercise performance. There have been few investigations as to whether RSP serves as an ergogenic aid to improve resistance exercise performance, particularly muscular endurance. Purpose: The purpose of this study was to investigate acute RSP (VitaSpinach^®) supplementation on muscular endurance and velocity during bench press exercise. Methods: In a double-blind, counterbalanced crossover manner, resistance-trained males (n = 14) were subjected to two supplement conditions as follows: (1) placebo (PL; purple sweet potato) or (2) red spinach powder (RSP; 400 mg NO₃). Supplements were consumed 2 h prior to exercise and blood was collected immediately pre-exercise to determine NO₃/NO₂ levels. To determine barbell velocity, participants completed two sets × two repetitions with maximal effort, while a rotary encoder measured mean barbell velocity. Following this, participants performed three sets × repetitions to exhaustion (RTE) at 60% of 1-Repetition Maximum (1-RM), separated by 2 min of rest, to determine muscular endurance. Local (lRPE) and global (gRPE) ratings of perceived exertion were measured after exercise. Blood NO₃/NO₂, RTE, mean velocity, lRPE, and gRPE were compared between supplement conditions. Results: RSP resulted in significantly higher blood levels of total NO₃/NO₂ (p < 0.001) compared to PL. RSP did not result in superior total RTE (p = 0.935) but increased mean velocity (p = 0.035) compared to PL. Both lRPE (p = 0.027) and gRPE (p = 0.028) were significantly reduced with RSP supplementation. Conclusions: Findings suggest acute RSP ingestion increased NO₃/NO₂ and bench press velocity. While muscular endurance remained unchanged, RSP resulted in lower perceptions of exertion. Full article

Wisdom in negotiation is increasingly vital in managing conflicts, yet its behavioural expression remains underexplored. This study explores the behavioural signatures of individuals nominated as wise negotiators within an organisational context. There were 48 participants recruited as wise negotiators from a larger pool of 313 participants. There were three manipulations used: archetypes (personality), reciprocity style, and emotionality, resulting in a 4X3X2 design (24 conditions). Participants were also asked to fill out various wisdom related questionnaires. Each participant had to go through 24 conditions separately before playing an investment game each time. For the analysis purpose, three-way repeated ANOVA and three-way repeated ANCOVA were used. The results revealed that there was a difference in how wise negotiators negotiate differently with different archetypes (p < 0.01), reciprocity (p < 0.01) and emotional situations (p < 0.01). Additionally, there were also interaction effects of archetypes, reciprocity and emotional situations (p < 0.05). Notably, when wisdom variables were statistically controlled, these differences became nonsignificant. A supplementary 2 × 2 design explored gender interactions, showing that outcomes differed by opponents’ gender but not by the gender of the wise negotiator. This finding highlights the role of wisdom traits in strategic negotiation and has implications for training and selection in a high-stakes negotiation context. Full article

Torreya nucifera, a consumable botanical species native to the southern regions of Korea, has a history of ethnopharmacological application to treat inflammatory conditions. This study employed feature-based molecular networking and integrated with the GNPS database to separate and identify ten phenolic compounds from T. nucifera. We further investigated the therapeutic potential of these isolated compounds and their structural features in the context of rheumatoid arthritis. Protein–protein interaction networks, constructed using compound–target and disease-associated target data, identified NFKB1, RELA, and TNFRSF1A as key hub genes. Gene Ontology (GO) enrichment analysis revealed inflammatory response as the most significantly modulated biological process. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the NF–kB signaling pathway is the most critical of the regulatory cascades influencing the pathogenesis of rheumatoid arthritis. Molecular docking studies verified strong binding affinities between the identified compounds and key target proteins. Furthermore, Western blot results validate that T. nucifera extract suppressed the LPS-activated NF–kB signaling pathways by inhibiting p65 and IκBα phosphorylation. The results underscore the significance of T. nucifera and its anti-inflammatory properties in relation to rheumatoid arthritis, establishing a scientific basis to formulate plant-based products within functional foods, nutraceuticals, and therapeutic interventions targeting rheumatoid arthritis. Full article

The system of full compressible magneto-micropolar flows is discussed in 3D bounded domains with slip boundary conditions. Based on the energy method, after establishing some key a priori exponential decay-in-times rates of the strong solutions, we obtain both the global existence and exponential stability of strong solutions. In particular, it should be pointed out that the estimates of ${\parallel (\mathrm{curl}\mathbf{u},\mathrm{curl}\mathbf{w})\parallel }_{L^2}$ and ${\parallel (\mathrm{div}\mathbf{u},\mathrm{div}\mathbf{w})\parallel }_{L^2}$ are established separately, which implies that the growth rate of $(\mathrm{div}\mathbf{u},\mathrm{div}\mathbf{w})$ in $L^2$ are faster than that of $(\mathrm{curl}\mathbf{u},\mathrm{curl}\mathbf{w})$ under the condition that the diameter of the domain is suitably large. Compared with previous works, we no longer consider the pressure P as $\rho \theta$, but as variable in $(x,t)$, and directly deal with ${\parallel \nabla P\parallel }_{L^2}$. Based on slip boundary conditions, we established the $L^p$-norm for the gradient of effective viscous flux, and the term ${\parallel \nabla P\parallel }_{L^2}$ can be controlled by $\parallel (\nabla {\mathbf{u}}_t,\nabla {\mathbf{w}}_t,\nabla {\mathbf{b}}_t){\parallel }_{L^2}$. Through precise calculations, we found that $\parallel (\nabla {\mathbf{u}}_t,\nabla {\mathbf{w}}_t,\nabla {\mathbf{b}}_t){\parallel }_{L^2}$ is dependent on ${\parallel \nabla P\parallel }_{L^2}$. Therefore, the smallness condition we propose does not depend on the $L^r$-norm of the density gradient, which means that density can contain large oscillations. Full article

Background: Cortisol is known as the main hormone released during stress responses in cattle and has been used to assess various stressors, including heat stress. This study investigated hair cortisol concentration (HCC) in different hair coat colors in dairy cows under natural heat stress conditions (temperature humidity index = 75). Methods: Hair samples were collected from the forehead region of ten multiparous cows (Brown Swiss, Montbéliarde, and Holstein) per group color at both the beginning and end of a three-week peak summer period in 2024 in the region of Jendouba, North Tunisia. Cows were grouped according to hair coat color (black, brown, red, white, and yellow) for subsequent analysis. Hair samples were prepared using a methanol-based separation protocol and analyzed via enzyme-linked immunosorbent assay (ELISA). Results: Meteorological data confirmed that cows were sustained under heat stress, with an average temperature humidity index value of 75; results indicated that black hair had considerably more HCC than white hair (p < 0.05). The results showed that there is a significant difference between HCC under three clusters (p < 0.05) according to hair color. Conclusions: The study emphasizes that hair color, along with factors such as breed and environmental conditions, should be carefully considered when using HCC to assess stress in cattle beyond simply black or white hair color. Full article

Pharmaceutically active compounds (PhACs), pesticides, and poly- and perfluoroalkyl substances (PFAS) are increasingly detected in surface waters at trace concentrations, raising concerns for both aquatic systems and, consequently, human health. Conventional solutions are insufficient to achieve complete removal at trace compound concentrations, highlighting the need for advanced separation technologies. This study aims to comprehensively analyze rejection and removal mechanisms of selected PhACs, pesticides, and PFAS present in water solutions at reported environmentally relevant concentrations (300 ng L⁻¹), using two nanofiltration (NF) and one reverse osmosis (RO) polyamide membrane. PhACs, pesticides, and PFAS were selected to cover a broad range of physicochemical properties, specifically molecular mass (MM), dissociation constant (pKa), and octanol–water partition coefficient (logK_o/w). Rejection values ranged from 42.1% (acetaminophen) to apparent 100% (for multiple compounds), depending on water pH, solute properties, and membrane characteristics. Size exclusion and electrostatic interactions were identified as the primary removal mechanisms, with hydrophobic interactions having a lower impact, particularly for carbamazepine, bezafibrate, and perfluorooctane sulfonic acid (PFOS). Addition of sodium chloride (3 g L⁻¹) decreased rejection of most negatively charged compounds due to suppression of membrane surface charge, although clarithromycin and ofloxacin exhibited improved rejection. Presented results provide fundamental insight into compound-specific membrane rejection and highlight the importance of membrane–solute interactions under environmentally realistic conditions. The results support further optimization of NF and RO for targeted compound rejection and provide a baseline for data-driven membrane process modeling. Full article