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This study experimentally investigates a Regenerative Organic Rankine Cycle (RORC) system that operated under varied cryogenic conditions using liquid nitrogen (LN2) as the heat sink. A three-fluid heat exchanger (TFHE) is applied to this system instead of a condenser and regenerator to realize the RORC system. The condensing pressure changes between 0.08 MPa and 0.6 MPa, and applying the R290 as the working fluid. The condensing pressure effect on system performances, including electrical power output, cold thermal efficiency, and exergetic efficiency, are investigated under different LN2 flow rates. The comparisons between basic ORC (BORC) and RORC under the same working conditions are conducted. The results demonstrate that as the condensing pressure remains constant, the higher LN2 flow rate is beneficial to the overall performance of the RORC system. The maximum cold thermal efficiency and power generation obtained in the RORC system are 13.35% and 738.81 W, which are obtained at the LN2 flow rate of 120 kg/h and the condensing pressure of 0.25 MPa. Additionally, the RORC shows improved performance with an exergetic efficiency of 10.68%. The results would be a technological guide for the construction and improvement of the system with cold energy recovery. [ABSTRACT FROM AUTHOR]

• We designed and fabricated nanophotonic chalcogenide waveguides from Ge 28 Sb 12 Se 60 (GeSbSe) glass using electron-beam lithography and plasma etching. We optimized the waveguide dimensions for efficient supercontinuum generation pumped at 1550 nm through dispersion engineering and nonlinear optical simulations. • By pumping the engineered GeSbSe waveguides with femtosecond pulses at 1550 nm wavelength, the authors demonstrated on-chip supercontinuum generation spanning over 750 nm. Nanophotonic chalcogenide waveguides (ChGs) fabricated from Ge 28 Sb 12 Se 60 (GeSbSe) glass were designed and fabricated for efficient supercontinuum (SC) generation. Dispersion engineering and nonlinear optical simulations were used to optimize the cross-sectional dimensions of the strip waveguides for pumping at 1550 nm. The waveguides were fabricated using e-beam lithography and plasma etching to achieve submicron confinement and high optical quality. By pumping anomalous dispersion engineered waveguides with femtosecond pulses at 1550 nm wavelength, supercontinuum generation spanning over 750 nm was demonstrated on-chip. The findings provide experimental evidence of the potential applications of GeSbSe waveguides in nonlinear photonics, highlighting their advantages in terms of performance and spatial efficiency. [ABSTRACT FROM AUTHOR]

Aim. This study aimed to predict the key targets and endocrine mechanisms of Guizhi Fuling Wan (GZFLW) in treating adenomyosis (AM) through network pharmacology, molecular docking, and animal experiment verification. Methods. The related ingredients and targets of GZFLW in treating AM were screened out using TCMSP, BATMAN-TCM, SwissTargetPrediction, and PubChem Database. Then, the protein-protein interaction (PPI) analysis and the network of compound-hub targets were constructed. At the same time, the key targets were uploaded to the Metascape Database for KEGG pathway enrichment analysis. After that, the molecular docking technology of the main active components and hub targets was performed. Furthermore, animal experiments were used to verify the results of network pharmacology analysis. Results. A total of 55 active ingredients of GZFLW and 44 overlapping targets of GZFLW in treating AM were obtained. After screening, 25 hub targets were collected, including ESR1, EGF, and EGFR. Then, the KEGG pathway enrichment analysis results indicated that the endocrine therapeutic mechanism of GZFLW against AM is mainly associated with the estrogen signaling pathway, endocrine resistance, and an EGFR tyrosine kinase signaling pathway. Then, molecular docking showed that the significant compounds of GZFLW had a strong binding ability with ERα and EGFR. More importantly, the animal experiments confirmed that the GZFLW could downregulate the abnormal infiltration of the endometrial epithelium into the myometrium and had no interference with the normal sexual cycle. This effect may be directly related to intervening the local estrogen signaling pathway of the endometrial myometrial interface (EMI). It may also be associated with the myometrium cells' estrogen resistance via GPER/EGFR signaling pathway. Conclusion. The endocrine mechanism of GZFLW in treating AM was explored based on network pharmacology, molecular docking, and animal experiments, which provided a theoretical basis for the clinical application of GZFLW. [ABSTRACT FROM AUTHOR]

To improve interpersonal comparability of self-reported measures, anchoring vignettes are increasingly collected in surveys and modeled as the hierarchical ordered probit (HOPIT) model. This paper—based on the idea of psychological distance—relaxes the assumption of vignette equivalence in the HOPIT by allowing for heteroscedasticity in respondents' perceptions of vignettes. Particularly, we assume that respondents who are more similar to a vignette are more familiar with the condition described and therefore are capable of forming a more precise perception of the vignette. We show evidence in favor of this extended HOPIT through Monte Carlo simulations and an application concerning self-reported vision difficulty from the WHO Study on Global Aging and Adult Health (SAGE). [ABSTRACT FROM AUTHOR]

[Display omitted] • Rice grains in temperate regions have higher concentration of Ni. • Partition coefficient of Ni between clays and Fe oxides is higher in tropical soils. • Most of Ni in tropical soils is found in kaolinite. • Chemical weathering intensity regulates the accumulation of Ni in rice grains. Globally, a high concentration of nickel (Ni) in agricultural soil is closely related to basalt weathering. Rice grains readily accumulate Ni, however, the evolution of Ni distribution and mobility in paddy fields with basalt weathering remain unclear. This study investigated the distribution, geochemical fraction, and mobilization of Ni in basalt bedrock-paddy soil-rice plant continuums under contrasting climates through a combination of field surveys, chemical extractions, X-ray diffraction, and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) analyses. Results show that the soils developed in tropical climates were more enriched in Ni than those in temperate climates. The concentration of Ni in rice grains from the studied temperate regions (3.71 ± 2.01 mg/kg) was higher than that in the tropical regions (0.57 ± 0.37 mg/kg). The concentration of Ni bound to Fe (hydro)oxides in paddy soils from temperate regions was five times higher than that in tropical regions. In contrast, the concentration of Ni found in phyllosilicate clays (mainly smectite/illite) in paddy soils from the temperate regions was only ∼1/4 of that of clay (mainly kaolinite) in the tropical paddy soils, and the ratio of Ni concentration in phyllosilicate clays to highly reactive Fe (hydro)oxides in paddy topsoil in temperate regions was one order of magnitude less than that in tropical regions, which contributes to the low bioavailability of Ni in tropical paddy soils. Furthermore, the accumulation of Ni in rice grains was insensitive to soil pH in tropical regions but showed significant negative correlations with the degree of chemical weathering (chemical index of alteration and index of laterisation) in temperate and tropical regions. These observations support the hypothesis that chemical weathering and the dissolution–recrystallization of Fe (hydro)oxides induced by frequent redox fluctuations in paddy soils cause Ni repartition between Fe (hydro)oxides and phyllosilicate minerals, which influence Ni geochemical cycling and bioavailability, and fundamentally regulate Ni accumulation in rice. This study elucidates the mechanism and controlling factors underlying Ni partition in the basalt-paddy soil-rice plant continuum under distinct climates, providing new insights into the understanding of geochemical behavior and environmental fate of Ni. [ABSTRACT FROM AUTHOR]

Basalt-derived agricultural soil is widely distributed around the world and is extensively used as a medium to plant many kinds of crops. Weathering of basalt can release heavy metals into the soils and may cause health risks via the food chain. However, the geochemical behavior and the potential human health risks of heavy metals remain poorly understood in these agro-systems. In this study, basalt bedrock, paired topsoil and crops (wheat and rice) samples were collected from a basaltic area located in Xuyi County, eastern China. Concentrations and bioavailability of heavy metals in the basalt-topsoil-crop system were measured to determine their geochemical behavior during the weathering and transfer processes as well as their potential risk to human health. Our results showed that basalt and topsoil were characterized by high levels of Ni, Cr and Zn. Topsoil and crop grains were highly polluted by Ni, and Ni accumulated more readily in rice grains than in wheat grains. Nickel, a high-risk metal in topsoil was mainly derived from the basalt bedrock, and its enrichment in topsoil was significantly related to the Fe oxide content of the soils. The accumulation of Ni in crop grains was mainly controlled by soil pH, and the 0.01 M CaCl 2 extractable Ni was a good indicator in predicting Ni accumulation in crop grains. Risk analysis revealed that there are significant health risks to local inhabitants if rice grains contaminated with heavy metals are ingested. To our best knowledge, this is the first study to investigate the flow of heavy metals in a basalt-topsoil-crop-human system that focuses on geochemical behavior and human health risk. This study will aid the strategic design of evaluation and remediation protocols for basaltic soil. Unlabelled Image • The weathering of basaltic bedrock causes accumulation of heavy metals in topsoil. • Ni was the most typical pollutant found in the local topsoil and crop grains in the study area. • Ni was more readily accumulated in rice grains than in wheat grains. • The digestion of grains poses significant potential health risk to local residents. [ABSTRACT FROM AUTHOR]

The flow pattern transformation and heat transfer characteristics of refrigerant flow in the shell side of LNG spiral wound heat exchangers (SWHEs) have a significant influence on the performance of SWHEs. A numerical model was developed to predict the flow pattern and heat transfer characteristics of two-phase flow boiling in the shell side of SWHEs. In the model, a submodel for simulating flow pattern was developed by employing Volume of Fluid combined with a Continuous Surface Force (VOF-CSF model), and a submodel for the mass transfer rate was developed; the forces and the heat and mass transfer rates were introduced into the control equations as the source terms. The experimental validation of the model shows that, the deviation of heat transfer coefficient is within ±20%, and the predicted flow patterns are consistent with those observed ones. Based on the proposed model, the flow pattern maps were developed, and the flow pattern transformation principles and heat transfer characteristics in SWHE shell side under different conditions were analyzed. The maximum heat transfer coefficient for SWHE shell side is enhanced by 10.5% as the longitude tube pitch increases from 1 mm to 3 mm, and reduced by 8.9% as the tube diameter decreases from 12 mm to 8 mm. • Numerical model of flow pattern and heat transfer of SWHE shell side was developed. • Flow pattern maps of different geometry parameter SWHEs were summarized. • Heat transfer characteristics of SWHE with different structure were analyzed. [ABSTRACT FROM AUTHOR]

Rhenium, mostly found in sedimentary organic matter, is used to estimate petrogenic organic carbon (POC) weathering rates. Understanding its cycle on the Earth's surface is key to using riverine dissolved rhenium (Re) as a marker for the weathering of POC. Yet, human interference, especially from the mining, industrial and chemical sectors that commonly use Re, can affect use of this marker. In this study, Yangtze River water samples and industrial wastewater samples from 2018 to 2019 were collected and Re and major ion concentrations were analyzed to investigate the major sources and anthropogenic effects on riverine dissolved Re flux. The concentration of dissolved Re in the Yangtze River ranged from 67.7 to 167.6 pmol/L, much higher than the world average of 2.3 pmol/L and the calculated annual Re flux is 16.98 tons. Based on the assumption that denudation materials in the Yangtze River basin are entirely weathered, the calculated upper limit of the Re flux provided by the natural weathering process is approximately 1.48 t/yr, accounting for only 8% of the measured total Re flux. Therefore, we estimate that human activities contributed at least 92% of the dissolved Re flux in the Yangtze Basin. Analyses of wastewater from factories closely related to Re use in the Yangtze River basin showed little influence on the dissolved Re flux, so other human activities along the Yangtze River may contribute a significant amount of Re, such as mining or coal utilization. With the dominant control of human activities on riverine dissolved Re flux in the Yangtze River, the annual Re flux may have increased from 9.44 t/yr to 16.98 t/yr from 2007 to 2019. Our study suggests that human activities may rapidly and significantly change the geological elemental cycle of Re on decadal timescales. • 16 Time-series water samples were collected from the Yangtze River in Nanjing. • Water samples were analyzed for Re concentrations. • Dissolved Re flux of the Yangtze River basin is mostly controlled by human activities. • Human activities may have rapidly perturbed the rhenium geochemical cycle in the last decade. [ABSTRACT FROM AUTHOR]

Abstract Brucellosis remains one of the most common zoonotic diseases globally with more than a half million human cases reported annually. The Brucella reservoir associated with livestock brucellosis poses a significant threat to public health, and awareness of the seroprevalence and spatial distribution of livestock brucellosis is valuable for the prevention and control of diseases caused by Brucella , especially human brucellosis. Therefore, we conducted a systematic review and meta-analysis to evaluate the seroprevalence of brucellosis in dairy cattle in China. We retrieved 88 studies related to the seroprevalence of brucellosis in dairy cattle in China in which samples were harvested between 2008 and 2018. The results of our systematic review and meta-analysis reveal that the overall seroprevalence of brucellosis in dairy cattle herds in China was 1.9% during the selected period, rising from 1.6% in 2008–2012 to 2.6% in 2013–2018. In Northern China, where the traditional agropastoral areas with more developed animal breeding industry are located, the brucellosis seroprevalence was >10%. In contrast, the seroprevalence of brucellosis in Southern China reached only 5.5%. At the provincial level, the highest brucellosis seroprevalence in dairy cattle was estimated at >30% in Jilin province, followed by Shanxi, Ningxia, Inner Mongolia, and Guizhou, each with a prevalence of 10–20%. Additionally, the seroprevalence of brucellosis in some local areas was >30% or even >50%, indicating that Brucella infection was highly endemic in dairy herds in China. Our data may facilitate the prevention and control of brucellosis in domestic animals in China. Further epidemiological surveillance and the administration of a comprehensive monitoring program to determine the risk factors associated with brucellosis incidence in humans and domestic animals are recommended to refine brucellosis control strategies. [ABSTRACT FROM AUTHOR]