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Reference evapotranspiration (ET0) is of great significance in studies of hydrological cycle, agricultural water resources, and hydrometeorology. The present study collected daily meteorological data at 536 meteorological stations in China from 1984 to 2019, calculated daily ET0 using the FAO Penman–Monteith equation, analyzed the spatial distribution and temporal variation characteristics of ET0 and meteorological variables at four different spatial scales (continental, regional, provincial, and local), and discussed the sensitivity of ET0 to the meteorological variables and the contribution rates of the meteorological variables to the ET0 variations. The results showed that ET0 increased at 406 out of the 536 stations (75.7%), with the trends being significant at 65 stations at the 5% significance level, and 147 at the 1% significance level. The slope calculated using Sen's method and linear trend method showed that the annual ET0 at the continental scale increased by approximately 12 mm/decade. Most of the stations showed decreasing trends in relative humidity (Hm), sunshine duration (SD), and wind speed at 2 m height (U2) while increasing trends in the maximum air temperature (Tmax) and minimum air temperature (Tmin). ET0 was most sensitive to Hm (sensitivity coefficient, St = −0.66), followed by Tmax (St = 0.29), SD (St = 0.18), U2 (St = 0.16), and Tmin (St = 0.07). Most of the stations showed increasing trends in St for Hm (56.16%), Tmax (72.95%), Tmin (87.31%), and U2 (90.49%), and decreasing trends for SD (69.78%). The variations in Hm, Tmax, and Tmin increased the ET0 at most of the stations (82.28%, 98.13%, and 69.03%, respectively). The variations in SD and U2 decreased ET0 at most of the stations (66.04% and 56.34%, respectively). Some ET0 characteristics in a few regions can be well described using a single spatial scale. However, most regions exhibited significantly different ET0 characteristics across spatial scales. The results of this project can provide reference for hydrological analysis and agricultural water management under climate change conditions and provide data and information for other hydrology-related applications. [ABSTRACT FROM AUTHOR]

Background: Obesity is one of the most significant causes of morbidity and mortality worldwide. Current studies suggest a new type of obesity, normal weight obesity (NWO), which is defined as having a normal body mass index (BMI), but a high-fat percentage increases the risk of cardiometabolic risk factors (CMRFs). This systematic review and meta-analysis aimed to pool the association between NWO with CMRFs. Methods: A systematic search of the literature in all available electronic databases, including Scopus, Web of Science, EMBASE, and PubMed, was performed until October 2021. All English studies that assessed the association of NWOs [compared to normal weight non-obese (NWNO)] and the CMRFs were included. Two investigators extracted data and performed a quality assessment. The heterogeneity between studies was assessed with I-squared and Cochran's Q tests. Odds ratio (OR) was used as an effect size to pool the association of NWO with CMRFs. Results: Twenty-five articles that met the inclusion criteria entered the study. The total number of participants was 177,792, with an age range of 13 to 75 years. Most studies were conducted on the general population (adults) and were from China. The result of fixed-effect model meta-analysis indicated an increased odds of hyperglycemia (OR:1.50, 95%:1.23, 1.76), high TG (OR:1.90, 95% CH:1.44, 2.35), low HDL (OR: 1.28, 95% CI:1.06, 1.49) and diabetes (OR:1.39, 95% CI:1.30, 1.49). Moreover, the random effect meta-analysis showed that NWO increased the odds of dyslipidemia (OR:1.83, 95% CI:1.61, 20.4), HTN (OR:1.40, 95% CI:1.28, 1.51) and metabolic syndrome (OR:1.92, 95% CI:1.58, 2.26). Moreover, the mean of all CMRFs except plasma glucose in NWO subjects was statistically higher than NWNO subjects (p-value<0.05). Conclusion: The present study showed that NWO increased the odds of CMRFs. These findings indicate the inadequacy of the BMI measurement and the need for body fat assessment for a better obesity risk assessment. [ABSTRACT FROM AUTHOR]

CO 2 sequestration is among the most anticipated methods to mitigate the already detrimental concentrations of CO 2 in the atmosphere. Among sequestration methods, CO 2 injection into oceans is of great significance due to the oceans' large sequestration capacity. However, there are concerns about the changes in water pH as CO 2 is injected into oceans. Previous studies in conditions representative of CCS in the ocean are scarce. In the current study, we experimentally measure the pH and solubility at pressures up to 400 atm, temperatures between 283 and 298 K, and different aqueous solutions in a high-pressure autoclave reactor. The results indicated that increasing pressure increases the solubility of CO 2 in aqueous solutions, resulting in lower pH values. In contrast, increasing salinity and temperature lowers the solubility and, as a result, increases the system's pH. Among all the tested aqueous solutions, the synthetic seawater mimicked that of a potential injection point in the South China sea, exhibiting the highest salting-out effect and, therefore, the lowest solubility (i.e., the highest pH). The experimental dataset of this study was fed to a machine learning algorithm, Group modeling data handling(GMDH), to develop an explainable, white-box solubility model. The model could predict the pH as a function of solubility, temperature, pressure, and salinity with an accuracy of 0.87. The pH values from the model were compared to those from previous studies, and a good agreement among the values was found. Lastly, a parameter importance analysis was conducted to shed further light on the model's performance. Pressure and temperature were found to be the most and the least influential factors, respectively. As the implantation of the technology is currently being considered in China, the current study can pave the way to better understand the interactions and mechanisms involved in conditions representative of ocean sequestration before large-scale operations. • Solubility and pH of CO2 in aqueous solutions was experimentally investigated. • Both parameters are essential for different CCS operations specifically CCS in oceans. • An accurate, data-driven pH equation was developed based on the experimental data. [ABSTRACT FROM AUTHOR]

Most of the shale oil reservoirs in China are of medium to low maturity. The effective exploitation of hydrocarbon resources in such formations is technically challenging. This study explores the impact of various thermal stimulation methods on low-maturity shale oil reservoirs, focusing on conventional heating, microwave heating, and water-saturated microwave heating methods. A suite of techniques, including small angle neutron scattering (SANS), mercury injection capillary pressure (MICP), and field emission-scanning electron microscopy (FE-SEM) after wood's metal injection were used to investigate the evolution of microstructures under different thermal stimulation. This integrated approach allows for a comprehensive characterization of reservoir connectivity and permeability across multiple scales, from visually observable centimetre and millimetre scales down to the nanoscale. The response of shale to thermal stimulation is significantly influenced by its mineral composition, with shales rich in absorbent minerals like pyrite undergoing selective heating when exposed to microwaves, leading to new pores and fracture formations. The use of CM-SANS has revealed substantial untapped hydrocarbon potential within the reservoir, emphasizing the importance of thermal stimulation in enhancing production. Furthermore, integrating microwave irradiation with hydraulic fracturing effectively increases the number of pores, micro-fractures, and natural fracture openings, mitigates the hydration effects of hydraulic fracturing, and increases permeability by three orders of magnitude. The results indicated that microwave combined with hydraulic fracturing positively impacts the production from low-maturity reservoirs and provides the theoretical basis for in-situ thermal recovery of shale oil. [Display omitted] • Various thermal treatment methods is studied on shale for the best technique. • Multiple methods were used to analyze shale structure and flow properties. • Water-saturated microwave increased permeability 3 times. • A comprehensive development strategy for low-maturity shale is proposed. [ABSTRACT FROM AUTHOR]