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AbstractPhysical exercise spaces emerged as popular facilities due to recognizing the significance of physical well-being. This study investigates the relationship among physiological responses, human body energy transfer modes, and indoor environmental conditions in influencing thermal comfort perception within indoor physical exercise space. Seven male participants engaged in a 30 min constant-work-rate cycling exercise and a 20 min resting period in a climatic chamber. The physiological and environmental responses were recorded during the experiments, and the body’s energy transfer modes were calculated using the collected data. The dataset was prepared using the 2 min averages of the collected data and calculated parameters across the experiment phases, including the features of skin temperature, core temperature, skin relative humidity, heart rate, oxygen consumption, body’s heat transfer rates through convection, radiation, evaporation, and respiration, net metabolic heat production rate (metabolic rate minus external work rate), indoor air temperature, indoor relative humidity, air velocity, and radiant temperature. Gradient boosting regressor (GBR) was selected as the analyzing method to estimate predicted mean vote (PMV) and thermal sensation vote (TSV) indices during exercise and resting periods using features determined in the study. Thus, the four GBR models were defined as PMV-Exercise, PMV-Resting, TSV-Exercise, and TSV-Resting. In order to optimize the models’ performances, the hyperparameter tuning process was executed using the GridSearchCV method. A permutation feature importance analysis was performed, emphasizing the significance of net metabolic heat production rate (24.2%), radiant temperature (17.0%), and evaporative heat transfer rate (13.1%). According to the results, PMV-Exercise, PMV-Resting, and TSV-Resting GBR models performed better, while TSV-Exercise faced challenges in predicting exercise thermal sensations. Critically, this study addresses the need to understanding the interrelationship among physiological responses, environmental conditions, and human body energy transfer modes during both exercise and resting periods to optimize thermal comfort within indoor exercise spaces. The results of this study contribute to the operation of indoor gym environments to refine their indoor environmental parameters to optimize users’ thermal comfort and well-being. The study is limited to a small sample size consisting solely of male participants, which may restrict the generalizability of the findings. Future research could explore personalized thermal comfort control systems and synergies between comfort optimization and energy efficiency in indoor exercise spaces.

La physique ouverte et cachée des saveurs lourdes dans les collisions nucléaires à haute énergie entre dans une nouvelle étape passionnante vers une compréhension plus claire des nouveaux résultats expérimentaux avec la possibilité de les lier directement à l'avancement de la chromodynamique quantique en treillis (QCD). Des résultats récents d'expériences et de développements théoriques concernant la dynamique des saveurs lourdes ouvertes et cachées ont été débattus lors de l'atelier de Lorentz Tomography of the Quark-Gluon Plasma with Heavy Quarks, qui s'est tenu en octobre 2016 à Leiden, aux Pays-Bas. Dans cette contribution, nous résumons les compréhensions communes identifiées et les stratégies développées pour les cinq prochaines années, qui visent à acquérir une connaissance approfondie des propriétés dynamiques du plasma quark-gluon. La física de sabor intenso abierta y oculta en colisiones nucleares de alta energía está entrando en una nueva y emocionante etapa para alcanzar una comprensión más clara de los nuevos resultados experimentales con la posibilidad de vincularlos directamente con el avance en la cromodinámica cuántica reticular (QCD). Los resultados recientes de experimentos y desarrollos teóricos sobre dinámicas abiertas y ocultas de sabor intenso se han debatido en el Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, que se celebró en octubre de 2016 en Leiden, Países Bajos. En esta contribución, resumimos los entendimientos comunes identificados y las estrategias desarrolladas para los próximos cinco años, que tienen como objetivo lograr un conocimiento profundo de las propiedades dinámicas del plasma de quarks y gluones. Open and hidden heavy-flavor physics in high-energy nuclear collisions are entering a new and exciting stage towards reaching a clearer understanding of the new experimental results with the possibility to link them directly to the advancement in lattice Quantum Chromo-Dynamics (QCD). Recent results from experiments and theoretical developments regarding open and hidden heavy-flavor dynamics have been debated at the Lorentz Workshop Tomography of the Quark-Gluon Plasma with Heavy Quarks, which was held in October 2016 in Leiden, The Netherlands. In this contribution, we summarize identified common understandings and developed strategies for the upcoming five years, which aim at achieving a profound knowledge of the dynamical properties of the quark-gluon plasma. تدخل فيزياء النكهة الثقيلة المفتوحة والمخفية في التصادمات النووية عالية الطاقة مرحلة جديدة ومثيرة نحو الوصول إلى فهم أوضح للنتائج التجريبية الجديدة مع إمكانية ربطها مباشرة بالتقدم في الديناميكيات الكمومية الشبكية (QCD). تمت مناقشة النتائج الأخيرة من التجارب والتطورات النظرية المتعلقة بديناميكيات النكهة الثقيلة المفتوحة والمخفية في ورشة لورنتز للتصوير المقطعي لبلازما كوارك- غلوون مع الكواركات الثقيلة، والتي عقدت في أكتوبر 2016 في ليدن، هولندا. في هذه المساهمة، نلخص التفاهمات المشتركة المحددة والاستراتيجيات المطورة للسنوات الخمس القادمة، والتي تهدف إلى تحقيق معرفة عميقة بالخصائص الديناميكية لبلازما كوارك- غلوون.

In recent times, economic policy uncertainty (EPU) and geopolitical risk (GPR) are increasing significantly where the economy and environment are affected by these factors. Therefore, the goal of this paper is to investigate whether EPU and GPR impede CO2 emissions in BRICST countries. We employ second-generation panel data methods, AMG and CCEMG estimator, and panel quantile regression model. The conclusions document that most of the variables are integrated at I (1), and there exists co-integration among considered variables of the study. Moreover, we note that EPU and GPR have a heterogeneous effect on CO2 emissions across different quantiles. EPU adversely affects CO2 emissions at lower and middle quantiles, while it surges the CO2 emissions at higher quantiles. On the contrary, geopolitical risk surges CO2 emissions at lower quartiles, and it plunges CO2 emissions at middle and higher quantiles. Furthermore, GDP per capita, renewable energy, non-renewable energy, and urbanization also have a heterogeneous impact on CO2 emissions in the conditional distribution of CO2 emissions. Based on the results, we discuss the policy direction.

Carbon dioxide emission and GHGs are associated with fossil fuels which have adverse effects on the environment. The key intention of this paper was to determine the asymmetric effect of CO2 emission on expenditures, trade, FDI, and renewable energy consumption in Pakistan. An asymmetrical technique (nonlinear autoregressive distributed lag) was employed to validate the constructive and adverse relation among variables. Furthermore, the Granger causality test was also used to verify the unidirectional association amid variables. Study outcomes revealed that the adverse shocks of renewable energy consumption exposed expressively to upsurge CO2 emission in the short-run dynamics. Conversely, constructive shocks of renewable energy consumption display an adversative association with CO2 emission. Furthermore, the decreasing trend in foreign direct investment tends to impede the detrimental effects of CO2 emission. Additionally, the variable expenditures also create the non-eco-friendly impacts and manifest the positive linkage through CO2 emission. Trade possesses statistically insignificant linkage with environmental degradation. The results also disclose that positive as well as negative variations in the foreign direct investment expose to degrade the environmental eminence. Long-run results suggest the direct association between downward trend in renewable energy consumption and CO2 emission signifying that the pollution level decreases, and the upward trend in renewable energy consumption, however, demonstrates insignificantly positive effects. The results also disclose that positive as well as negative variations in the FDI lead to degrade the CO2 emission. Moreover, it is found that the expenditures soar the issue of pollution again in the long run. Finally, the consequence of trade on CO2 emission is adverse, as the outcome suggests. In order to improve the environmental policies for sustainable growth, the study provides direction toward a sustainable environment by reducing carbon dioxide emission.

Gold-based heterogeneous catalysts have attracted significant attention due to their selective partial oxidation capabilities, providing promising alternatives for the traditional industrial homogeneous catalysts. In the current study, the energetics of adsorption/desorption of alcohols (CH3OH/methanol, CH3CH2OH/ethanol, CH3CH2CH2OH/n-propanol) and esters (HCOOCH3/methyl formate, CH3COOCH3/methyl acetate, and CH3COOCH2CH3/ethyl acetate) on a planar Au(111) surface was investigated in conjunction with oxidative coupling reactions by means of temperature programmed desorption (TPD) and dispersion-corrected density functional theory (DFT) calculations. The results reveal a complex interplay between inter-molecular and surface-molecule interactions, both mediated by weak van der Waals forces, which dictates their relative stability on the gold surface. Both experimental and theoretical adsorption/desorption energies of the investigated esters are lower than those of the alcohols from which they originate through oxidative coupling reactions. This result can be interpreted as an important indication in favor of the selectivity of Au surfaces in alcohol oxidative coupling/partial oxidation reactions, allowing facile removal of partial oxidation products immediately after their generation preventing their complete oxidation to higher oxygenates.

The combined effects of surface rotation and using binary nanoparticles on the phase change process in a 3D complex-shaped vented cavity with ventilation ports were studied during nanofluid convection. The geometry was a double T-shaped rotating vented cavity, while hybrid nanofluid contained binary Ag–MgO nano-sized particles. One of the novelties of the study was that a vented cavity was first used with the phase change–packed bed (PC–PB) system during nanofluid convection. The PC–PB system contained a spherical-shaped, encapsulated PCM paraffin wax. The Galerkin weighted residual finite element method was used as the solution method. The computations were carried out for varying values of the Reynolds numbers (100≤Re≤500), rotational Reynolds numbers (100≤Rew≤500), size of the ports (0.1L1≤di≤0.5L1), length of the PC–PB system (0.4L1≤L0≤L1), and location of the PC–PB (0≤yp≤0.25H). In the heat transfer fluid, the nanoparticle solid volume fraction amount was taken between 0 and 0.02%. When the fluid stream (Re) and surface rotational speed increased, the phase change process became fast. Effects of surface rotation became effective for lower values of Re while at Re = 100 and Re = 500; full phase transition time (tp) was reduced by about 39.8% and 24.5%. The port size and nanoparticle addition in the base fluid had positive impacts on the phase transition, while 34.8% reduction in tp was obtained at the largest port size, though this amount was only 9.5%, with the highest nanoparticle volume fraction. The length and vertical location of the PC–PB system have impacts on the phase transition dynamics. The reduction and increment amount in the value of tp with varying location and length of the PC–PB zone became 20% and 58%. As convection in cavities with ventilation ports are relevant in many thermal energy systems, the outcomes of this study will be helpful for the initial design and optimization of many PCM-embedded systems encountered in solar power, thermal management, refrigeration, and many other systems.

Solution‐processed kesterite (copper zinc tin sulfide [CZTS]) solar cells attract significant attention owing to their low cost, ease of large‐scale production, and earth‐abundant elemental composition, which make these devices promising to fulfill the ever‐increasing demand of the photovoltaic (PV) industry. Compared to the performances of expensive vacuum‐based techniques, colloidal nanocrystal kesterite solar cells garner substantial interest due to their economical and rapid processing. Led by the hot‐injection method, organic solvent‐based techniques are widely adopted to realize CZTS nanocrystal inks. With organic solvents, ligand‐stabilized nanoparticles are formed leading to dispersive and homogenous kesterite inks. However, the presence of carbon‐rich ligands around the nanocrystal surface often leads to the formation of a fine‐grain layer that is rich in carbon content. The organic ligands decompose into amorphous carbon residues during a high‐temperature annealing process and hinder the grain growth process. The carbon‐rich fine‐grain (CRFG) layer generally poses a negative influence on the PV performance of the kesterite solar cell; however, few reports maintain their disposition about CRFG as innocuous. In this review study, a detailed discussion on CRFG is presented, aiming to understand the insights about its formation and impact on the device's performance.