Search Results (1,492)

Lithium-ion pouch cells exhibit significant irreversible expansion during long-term cycling, which determines overall performance and induces degradation failure without an appropriate mechanical fixture. However, the synergistic mechanism of mechanical pre-torque and battery state on battery electrochemical performance is unclear. To address this issue, this study reveals the electrochemical characteristic evolution of commercial lithium-ion pouch cells during cycling degradation, under varying mechanical pre-torques (0 N·m, 0.5 N·m, 1 N·m, and 1.5 N·m) and at different states of charge (SOCs, 0%, 25%, 50%, 75%, and 100%). Results indicate that moderate pressure (0.5 N·m) optimizes the electrode–electrolyte contact, reducing solid–electrolyte interphase resistance (R_SEI), ohmic resistance (R_O), charge transfer resistance (R_ct), and Warburg coefficient (W) by over 55%, 60%, 30% and 20%, respectively, compared with the free state. High pressure (1.5 N·m) induces impedance rebound due to pore compression, with the increment ranging from 20% to 40%. Furthermore, synergistic impact analysis proves that pressure alters impedance sensitivity to SOC, with changing rates amplifying from <5% per SOC unit under low pressure to 10–15% under high pressure, particularly exacerbating interface passivation at low SOC and side reactions at high SOC. Moreover, a Gaussian process regression (GPR) based adaptive SOC estimation model is developed, incorporating impedance features and pressure paths, achieving a root mean square error of 2.1% and enhancing accuracy by 10–15% over conventional methods in high-pressure scenarios. This study provides guidance for the next-generation pouch cell module design and management. Full article

Green technology innovation is widely recognized as a crucial driver for combating environmental pollution and achieving carbon reduction goals. Based on panel data from 30 provinces in China spanning 2006 to 2021, this study aims to examine the impact of green technology innovation (GTI) on carbon emission performance (CEP). The results indicate that (1) a significant U-shaped relationship exists between green technology innovation and carbon emission performance. (2) Heterogeneity analyses reveal that the effect is more pronounced in regions with higher levels of human capital, stronger macro-control, and a smaller urban–rural income gap. (3) Mechanism tests reveal that green technology innovation significantly improves carbon emission performance by driving the decarbonization of energy consumption structure. Furthermore, energy intensity negatively moderates the U-shaped relationship, leading to an “energy rebound effect”. (4) Spatial spillover analysis indicates that green technology innovation has a U-shaped impact on the carbon emission performance of adjacent regions. The findings of this study provide empirical evidence of and new perspectives on the crucial role of green innovation in achieving low-carbon sustainable development. Full article

This study investigates vertical surface displacements in an area previously impacted by extensive underground hard coal extraction, specifically focusing on the closed “Kazimierz-Juliusz” mine in the Upper Silesian Coal Basin (Poland). The cessation of mining operations and formal decommissioning do not necessarily signify the termination of ground instability; rather, the discontinuation of mine water pumping triggers a progressive groundwater rebound within the rock mass. This hydrogeological shift leads to a redistribution of stresses in the geological structure, inducing deformation processes that manifest as surface uplift. This research aims to characterize the temporal evolution and magnitude of post-closure surface elevation changes by integrating satellite radar interferometry with conventional geodetic surveys. The analysis, spanning a 28-month observation period, utilizes both Persistent Scatterer Interferometry (PSInSAR) and European Ground Motion Service (EGMS) data, complemented by precise geometric leveling. The results reveal a low-magnitude deformation process, with detected uplift rates reaching approximately 1 cm/year. The synergistic integration of InSAR-based monitoring and classical geodesy allowed for robust cross-validation, significantly enhancing the reliability of the findings both qualitatively and quantitatively. Full article

Animal manure represents a critical reservoir that facilitates the dissemination of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs). However, the current understanding of ARG evolution during extensive composting remains insufficient. This study systematically investigated two common aerobic composting techniques: push-flow trough composting (FC) and membrane-covered composting (FM). Results indicated that both processes demonstrated substantial antibiotic removal capacities, achieving total removal rates of 88.89% (FC) and 79.20% (FM). Nevertheless, their effectiveness in removing ARGs varied considerably. During the 31 days of composting, the total removal rates of ARGs were 59.97% (FC) and 76.11% (FM), while the removal rates for class 1 integron (intI1) were 2.31% (FC) and 69.13% (FM). With the exception of tetX, tetG, and tetW, all other ARGs exhibited a rebound during the later stage of the FC process. In contrast, the FM process effectively reduced the risk of ARG rebound during this phase, which can be attributed to its extended thermophilic period and the physical barrier effect of the semi-permeable membrane. Network analysis indicated that ARGs were primarily associated with Bacillota and Pseudomonadota. The Partial Least Squares Path Model (PLS-PM) revealed that the bacterial community was the main factor influencing ARG dynamics in FC, while in FM, both the bacterial community and intI1 were the primary drivers. This study provides critical insights for optimizing composting strategies to prevent the dissemination of antibiotic resistance. Full article

The aim of the present study was to analyze the validity and reliability of the My Jump Lab (My Jump Lab, Madrid, Spain) smartphone application for measuring the Dynamic Rebound Index (DRI) during drop jump testing. Seventeen physically active participants completed two testing sessions separated by 48 h. In each session, six drop jumps from a 40 cm box were performed while jump height, contact time and DRI were simultaneously recorded using a force platform and the app. Very large to nearly perfect correlations were observed between devices for all variables (r > 0.98). Agreement between methods was excellent, as indicated by the intraclass correlation coefficient (ICC > 0.97) and the concordance correlation coefficient (CCC > 0.93). Bland–Altman analysis revealed small systematic differences and narrow limits of agreement. The root mean square error (RMSE) was low, indicating minimal prediction error. Test–retest reliability between sessions was good for both devices (ICC = 0.825–0.925), and within-session reliability across attempts was high (ICC = 0.705–0.870). These findings indicate that My Jump Lab provides valid and reliable measurements of drop jump performance, including DRI, relative to a force platform, with potential utility in applied settings. Full article

In response to the issues of concentrated early-stage hydration heat and significant self-shrinkage in high-strength cementitious grouting materials at low water-to-binder ratios, improvements were achieved by co-blending granulated blast furnace slag (GGBS) with calcium sulphatoaluminate (UEA) and magnesium oxide (MEA) expansive agents. The workability, mechanical properties, volumetric stability and hydration heat characteristics of the composite system were systematically investigated, and the underlying mechanisms were elucidated through microscopic analysis methods such as XRD, TG and SEM. The results indicate that GGBS improved the fluidity of the pastes and promoted the development of later-stage strength. At the same time, GGBS delayed the peak of hydration heat release and reduced total heat release. In terms of volume deformation, UEA expanded rapidly and exhibited significant compensatory shrinkage in the early stages. MEA expanded slowly in the early stages and displayed more sustained expansion under wet-curing conditions, but experienced significant shrinkage rebound in the later stages under dry environments. Further research revealed that GGBS inhibited the expansion performance of both types of expansive agents. This is primarily attributed to the consumption of Ca(OH)₂ within the system, which reduced the alkalinity of the liquid phase. GGBS physically restricted the formation and development of expansion products by promoting the densification of the C–S–H gel. Full article

Mullite fiber materials are widely used in high-temperature thermal insulation applications, especially in aerospace thermal protection systems, due to their excellent thermal stability and low thermal conductivity. However, the material exhibits poor resistance to infrared radiative heat transfer at elevated temperatures. Accordingly, a dual-opacifier system composed of TiO₂ and K₂Ti₆O₁₃ binary whiskers was proposed as an effective strategy for enhancing thermal insulation performance. MF/TiO_2w and MF/TiO_2w/K₂Ti₆O_13w were fabricated in this study using a sol–gel method combined with in situ whisker growth. The results show that upright and interlaced K₂Ti₆O₁₃ and TiO₂ whiskers were uniformly grown on the fiber surface, contributing to a high infrared reflectance of 97.7% in the wavelength range of 2.5–10 μm. Under a front-side temperature of 1000 °C, the modified mullite fiber-based material exhibits a backside temperature of 177.8 °C, corresponding to a reduction of 71.8 °C compared with the original sample (249.6 °C), demonstrating significantly enhanced thermal insulation performance. In addition, the composite exhibits an ultralow density of less than 0.20 g/cm³. The as-prepared thermal insulation material shows a high rebound rate of 76.5% at a strain of 30%, indicating good elasticity. The results demonstrate that the developed composite exhibits excellent infrared shielding and structural stability, confirming that the binary whisker strategy effectively enhances the thermal insulation performance of the mullite fiber-based materials, highlighting its potential for high-temperature aerospace applications. Full article

This paper presents a comprehensive methodology for evaluating the flexibility potential of Electric Vehicle (EV) charging infrastructures from the perspective of a Charge Point Operator (CPO). The proposed framework is general and applicable to different types of charging infrastructures, provided that a set of operational assumptions is satisfied. These include unidirectional smart charging (V1G), AC charging sessions, preservation of user energy delivery when providing flexibility, and explicit modeling of rebound effects induced by temporal load shifting, requiring subsequent recovery of the shifted energy. The methodology is then applied to a real-world workplace charging facility to quantify the amount and temporal distribution of flexibility under different baseline charging strategies and levels of on-site photovoltaic integration. The analysis shows that a significant share of daily energy demand (i.e., between 20% and 36%) can be made available for flexibility services within the considered assumptions. Furthermore, the results highlight a strong operating cost trade-off between local optimization strategies and participation in system-level flexibility markets in the considered case study. Full article

The “New Arctic” regime represents a prominent climatic feature of the Arctic Ocean under global warming, characterized by persistently low summer sea ice extent, a marked reduction in sea ice thickness, and an expansion of open water areas at high latitudes. As a key indicator of the Arctic sea ice system, the spatiotemporal evolution of sea ice thickness and its underlying driving mechanisms remain incompletely understood. Using reanalysis datasets and remote sensing observations, this study identifies major abrupt shifts in Arctic sea ice thickness under the New Arctic regime, reveals the spatiotemporal distribution characteristics of winter sea ice thickness, and examines the driving factors from both thermodynamic and dynamic perspectives. The results show that the evolution of Arctic sea ice thickness can be divided into three phases: a high-level period during the “Traditional Arctic” (1979–1992), a rapid thinning period during the New Arctic transition (1993–2012), and a low-level stabilization period in the New Arctic regime (2013–2023). The first EOF mode of winter sea ice thickness depicts a spatially consistent thinning pattern across the entire Arctic, with the most significant reduction occurring in the multi-year ice regions north of the Canadian Arctic Archipelago and Greenland. The second EOF mode exhibits an out-of-phase variation between the Atlantic and Pacific sectors of the Arctic, accompanied by a shrinking amplitude and weakened regional oscillations. The coupling between surface air temperature and sea ice thickness displays distinct phase dependence: their negative correlation is strongest during the transition period (r = −0.78, p < 0.001) but becomes statistically insignificant in the New Arctic regime. Sea ice motion speed exhibits an overall accelerating trend, which extends from the marginal seasonal ice zones toward the high-latitude multi-year ice regions, accompanied by a notably enhanced sensitivity of sea ice motion to wind forcing. Sea ice volume flux through the Fram Strait is primarily controlled by ice motion speed, whose contribution to the flux is approximately 2.6 times that of ice thickness. The recovery of ice drift speed offsets the thinning of sea ice cover, leading to a partial rebound in volume flux during the New Arctic steady state. This study identifies the evolutionary patterns and drivers of Arctic sea ice thickness under the New Arctic regime, providing a scientific basis for further understanding the changes in the Arctic climate system and associated air–sea ice interactions. Full article

Background: Mycoplasma pneumoniae (MP) is an important pathogen responsible for community-acquired respiratory infections in children. Global surveillance during the COVID-19 pandemic revealed a marked decline in MP activity. However, beginning in early summer 2023, multiple regions across China reported an unexpected resurgence of MP infections, highlighting the need for detailed epidemiological analysis. Objective: This study aimed to characterize the epidemiological features of MP seropositivity among children in Chengdu, southwest China, and to compare its patterns between the COVID-19 pandemic and post pandemic periods. Methods: A retrospective analysis was conducted on MP testing data from 39,552 children with acute respiratory infections who were treated at West China Second University Hospital, Sichuan University, between January 2022 and December 2023. Results: Both the number of MP tests conducted and the seropositivity rate were significantly lower during the pandemic period than during the post pandemic phase. Compared with male children, female children were more susceptible to MP seropositivity. In terms of age distribution, seropositivity rates were highest among toddlers (1–3 years) and school-aged children (6–14 years). During the pandemic period (2022), MP antibody-positive cases were observed mainly between January and July, whereas in the post pandemic phase (2023), the epidemic peak shifted from June to December. Conclusions: In this single-centre study in Chengdu, nonpharmaceutical interventions (NPIs) implemented during the COVID-19 pandemic was associated with a marked reduction in MP transmission. After these restrictions were lifted, a rebound in MP antibody positivity was observed among children in Chengdu, compared to the NPI period (2022), the post-NPI period (2023) showed a later seasonal peak, which may represent a delayed return to pre-pandemic patterns. Continuous strengthening of MP surveillance is necessary to provide early warning of potential resurgences and outbreak risks. Full article

To investigate the effect of welding speed on the out-of-plane deformation of Q420 low-alloy high-strength steel thin plates, this study employed a three-dimensional digital image correlation system to monitor the deformation dynamically during TIG welding and cooling. Unlike existing studies that mostly focus on post-weld residual deformation or a single welding stage, this study, under a fixed current of 36 A and arc voltage of 14 V, sets welding speeds ranging from 4.5 to 11.8 mm/s, and for the first time systematically reveals the complete evolution path of Q420 thin plate (2 mm) welding deformation, which includes “thermal expansion—instability mutation—elastic rebound—residual stabilization”. The results show that the welding speed is significantly negatively correlated with the out-of-plane deformation. Although low-speed welding has a high peak plastic strain, the final residual strain is almost completely released; while high-speed welding has a low peak strain but retains a relatively high residual strain. This abnormal phenomenon reveals the deep mechanism that the accumulation and release of plastic strain are asymmetrically regulated by the welding speed. These findings support process optimization for high-strength steel thin plates. Full article

Background/Objectives: This study aimed to investigate the effects of synbiotics intake on body-composition-related indicators and physical performance in judokas from 4 weeks to 3 days before the match. The associations between the changes in fecal succinic acid concentration and the rate of change in physical performance were also examined. Methods: A total of 16 male participants from Aichi University Judo Club were included in a repeated-measures design to compare the effects of non-synbiotics and synbiotics. Body-composition-related indicators and physical performance were assessed, and fecal samples were collected 4 weeks and 3 days before the match. Results: From 4 weeks to 3 days before the match, no significant changes in body composition were observed in either the non-synbiotics or synbiotics group. Regarding physical performance, the non-synbiotics group demonstrated a significant reduction in countermovement jump and rebound jump power. In contrast, the synbiotics group maintained physical performance without significant changes. In addition, the change in fecal succinic acid concentration in the synbiotics group was negatively associated with the rate of change in physical performance, particularly rebound jump power (p = 0.052). In the rebound jump power-decreased group, the change in the fecal succinic acid concentration increased, whereas it decreased in the rebound jump power-increased group, and the difference between the two groups was statistically significant (p = 0.024; AUC = 0.84). Conclusions: Before the match, synbiotics intake and a reduction in the fecal succinic acid concentration may be associated with the maintenance of physical performance in judokas, which may have implications for match performance. Full article

Background: COPD remains a leading cause of hospitalization and mortality worldwide. This study aimed to analyze trends in COPD patients in Spain from 2016 to 2023, compare outcomes between patients with COPD as a primary versus secondary diagnosis, and identify factors associated with in-hospital mortality. Methods: Retrospective observational study using the Spanish database CMBD. 711.799 patients were analyzed. Demographic characteristics, Charlson Comorbidity Index (CCI), complications, mortality, and hospitalization costs were also evaluated. Multivariate logistic regression was used to identify mortality risk factors. Results: The overall hospitalization rate was 20.02 per 1000 admissions. It decreased by 30% during 2020–2021 before rebounding to peak levels in 2023. The proportion of female patients increased from 19.9% (2016) to 26.4% (2023). Patients with COPD as a secondary diagnosis had higher mortality (13% vs. 5.4%, p < 0.001), greater comorbidity burden (mean CCI 3.5 vs. 2.8), and higher costs. While overall admissions dropped in 2020, mortality peaked at 11.7%, and the number of patients with extremely severe disease nearly doubled. Independent risk factors for mortality included sepsis, age ≥ 66 years, CCI ≥ 3, and COVID-19. Conclusions: Hospitalization involving COPD in Spain showed pandemic-related fluctuations with increasing clinical complexity and increasing female sex. The higher mortality and cost associated with secondary COPD diagnosis highlight the need for comprehensive risk stratification of comorbid conditions and multidisciplinary management of these patients. Early identification of sepsis and CCI scores is essential to improve clinical outcomes in the aging population. Full article

Despite substantial reductions in precursor emissions, persistent summer ozone (O₃) pollution remains a critical environmental challenge in the North China Plain. This study integrated O₃ and volatile organic compound (VOC) data from the summers of 2014–2020 with an observation-based box model (OBM) to analyze O₃ pollution trends, VOC composition, sources, and sensitivity in Zhengzhou. The results indicated a continuous intensification of summer O₃ pollution, a progressive annual increase in polluted days, and an average annual concentration increase of 6.72 μg m⁻³ yr⁻¹. Further, the average VOC concentration on polluted days was 11.7% higher than that on non-polluted days, with alkanes dominating the component distribution, followed by aromatic hydrocarbons, alkenes, and alkynes. Subsequently, a source-apportionment model (positive matrix factorization) was used to identify six VOC sources: motor vehicle emissions (28.4%), industrial emissions (23.2%), solvent use (16.0%), liquefied petroleum gas/natural gas use (15.8%), fuel combustion (11.4%), and biological sources (5.4%). The photochemical age method corrected VOC loss during atmospheric transport, revealing that the traditional O₃-formation potential (OFP) method underestimated the contributions of alkenes and aromatic hydrocarbons, with isoprene, m/p-xylene, and ethylene as key species. Furthermore, multi-scenario simulations showed that solely reducing nitrogen oxides (NO_x) emissions caused an O₃ concentration rebound, while a 4:1 VOC to NO_x reduction ratio provided optimal control. By identifying the causal drivers of O₃ pollution in Zhengzhou, this study provides a scientific basis for designing precise emission-reduction strategies applicable to the North China Plain and analogous urban regions. Full article

The increasing frequency of extreme climate events challenges farmland nutrient management, yet single-year fertilization assessments fail to capture system adaptability. This study quantifies interannual changes in partial factor productivity (PFP) of rice, wheat, and rapeseed under contrasting climate years (typhoon–high temperature in 2024 vs. drought in 2025) using fixed-point monitoring data from 160 farming entities in the middle and lower Yangtze River, China. Fertilization rates, yields, and PFP were analyzed with paired t-tests and Kruskal–Wallis tests. Rice PFP increased significantly from 21.48 to 23.54 kg kg⁻¹ (p < 0.001) as yields rebounded under normal climate, while wheat PFP dropped sharply from 16.50 to 12.89 kg kg⁻¹ (p < 0.001) under drought, with farmers reducing fertilizer by only 1.1% despite a 22.7% yield loss. Rapeseed PFP remained persistently low (<7 kg kg⁻¹) with no significant changes. Family farms and cooperatives achieved higher PFP than ordinary farmers (p < 0.05). These findings demonstrate that fertilizer use efficiency is highly climate-sensitive and that single-year assessments are misleading. We recommend a dynamic, climate-smart fertilization framework integrating disaster type, crop species, and site-specific thresholds (e.g., real-time weather monitoring to adjust topdressing timing). Full article