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Semi-volatile organic compounds (SVOCs), such as phthalates and brominated flame retardants, is a kind of emerged pollutants due to wide application in indoor environment. Certain indoor SVOCs have been found to be associated with various adverse health effects, attracting large attentions of researchers. Due to relatively low vapor pressure, SVOCs are easily adsorbed on various surfaces including particles. Therefore, airborne SVOCs are always simultaneously presented in the gas-phase and particle-phase. Ventilation is an important means to improve indoor air quality. Different forms of indoor air distribution will affect the distribution of indoor pollutants and further affect the exposure to the human body. Therefore, in this paper, we selected Di (2-ethylhexyl) phthalate (DEHP) as the target compound and employed computational fluid dynamics (CFD) technique to simulate the emission of DEHP and the concentration distribution with different phases in a modeled room. Euler-Lagarian model is applied to simulate flow field, particle tracks and UDF (user defined function) was implemented to describe the dynamic adsorption of DEHP by the suspended particles. Furthermore, the effect of location of vent and airflow rate on indoor fate of DEHP were discussed and the effect of particle age on indoor fate of DEHP was also investigated.

Despite over 30 years of microbiome and skeletal muscle research, no quantitative analysis of sarcopenia and the microbiome literature had been conducted. Our bibliometric study examined research status, hotspots, and future trends. We utilized bibliometric techniques to search the Science Citation Index Extended Database on February 27, 2023, using the Bibliometrix package in R to create a map displaying scientific production and subject categories. Collaborative network maps between countries/regions were visualized using Scimago Graphica, while VOSviewer explored collaboration modes among individuals and institutions. We analyzed the top 25 emerging keywords, top co-occurring keyword networks, and co-occurring keyword clusters using CiteSpace. A total of 997 articles were retrieved for sarcopenia and microbiome, of which 633 papers were analyzed. Both the number of publications and total citation frequency had been continuously increasing. The United States had the highest total citation frequency, while China had the highest number of publications. Research on the impact of the microbiome on sarcopenia was in its nascent stage and spans multiple disciplines, including nutrition, microbiology, geriatrics, immunology, endocrinology and metabolism, molecular biology, and sports medicine. The University of Copenhagen contributed the most to the number of publications (n=16), with Tibbett M (n=7) and Hulver MW (n=7) among the top authors. The most published journal was "Nutrients" (n=24). Analysis of keywords and clusters revealed new research hotspots in microbes and sarcopenia, such as malnutrition, dietary fiber, signaling pathways, frailty, and intestinal permeability. Research on the impact of the microbiome on sarcopenia is in its infancy and spans multiple disciplines. Malnutrition, dietary fiber, signaling pathways, frailty, and intestinal microbes are currently research hotspots. Furthermore, the visual atlas analysis of research on microbes and sarcopenia helps to track the knowledge structure in research fields related to sarcopenia and microbes, providing direction for future research. [ABSTRACT FROM AUTHOR]

We develop a distributionally robust optimisation (DRO) model based on a risk measure for the parallel machine scheduling problem (PMSP) with random job processing times. We propose an underperformance risk index (URI) to control the extent of the total weighted completion time (TWCT) that exceeds target level T. With partially characterised uncertainty set information, we transform the model with URI to its equivalent mixed-integer linear programming (MILP) counterparts. Due to the NP-hardness of PMSP with different job weights, we design a hybrid algorithm with a heuristic assignment and exact subproblem for large-scale problems. The proposed hybrid algorithm reduces the computation time significantly at the expense of solution quality. We also introduce a reformulation approach under the setting of equally weighted and identical machines. Numerical results show that our model performs better than the distributionally β-robust optimisation models. Our proposed URI accounts for both the frequency and magnitude of violation from the target. The uncertainty set we used preserves a linear structure under partially characterised distributional information. Our computational results and sensitivity analysis show the effectiveness and efficiency of our proposed DRO model under various settings, including different problem sizes, different processing time variations, and information misalignment. [ABSTRACT FROM AUTHOR]

Atriplex canescens is widely cultivated as drought and salt-tolerant fodder in arid regions of Northwest China, which is used for photoremediation of degraded land and soil and water conservation. To explore the growth performance of A. canescens when exposed to drought and salt stress, seedlings were treated with a range of drought stress (WC1: 75 ± 3.6%, WC2: 49 ± 2.9% and WC3: 27 ± 2.5% of soil water content) and the corresponding drought stress with additional sodium salt supplementation (NaCl:Na2SO4 = 1:1 with the total concentration of Na+ set to 150 mM). The findings of this paper indicated that moderate sodium salt could stimulate the growth of A. canescens and effectively alleviate the deleterious impact of drought stress by increasing the turgor potential (ψt) and relative water content (RWC) and decreasing the leaf water osmotic potential (ψs). Furthermore, the photosynthetic capacity was improved and the negative effects of drought stress on photosystem II (PSII) were mitigated. The extra 150 mM sodium salt also markedly increased the contribution of Na+ to ψs and the contribution of betaine to ψs. In summary, these results indicate that A. canescens can adapt to drought stress by accumulating enough Na+ for osmotic adjustment (OA). Additionally, this paper is aimed to provide a fundamental basis for the utilization and cultivation of A. canescens as a favored pasture crop in the Qaidam basin, thus increasing the ecological and environmental benefits for arid regions worldwide. [ABSTRACT FROM AUTHOR]

In order to improve the wear resistance of offshore drilling equipment, CoCrFeNiMn high-entropy alloy coatings were prepared by cold spraying (CS) and high-speed oxygen fuel spraying (HVOF), and the coatings were subjected to vacuum heat treatment at different temperatures (500 °C, 700 °C and 900 °C). The friction and wear experiments of the coatings before and after vacuum heat treatment were carried out in simulated seawater drilling fluid. The results show that CoCrFeNiMn high-entropy alloy coatings prepared by CS and HVOF have dense structure and bond well with the substrate. After vacuum heat treatment, the main peaks of all oriented FCC phases are broadened and the peak strength is obviously enhanced. The two types of coatings achieve maximum hardness after vacuum heat treatment at 500 °C; the Vickers microhardness of CS-500 °C and HVOF-500 °C are 487.6 and 352.4 HV0.1, respectively. The wear rates of the two coatings at room temperature are very close. CS and HVOF coatings both have the lowest wear rate after vacuum heat treatment at 500 °C. The CS-500 °C coating has the lowest wear rate of 0.2152 mm3 m−1 N−1, about 4/5 (0.2651 mm3 m−1 N−1) of the HVOF-500 °C coating. The wear rates and wear amounts of the two coatings heat-treated at 700 °C and 900 °C decrease due to the decrease in microhardness. The wear mechanisms of the coatings before and after vacuum heat treatment are adhesive wear, abrasive wear, fatigue wear and oxidation wear. [ABSTRACT FROM AUTHOR]