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The purpose of this paper is to study the feasibility of real-time monitoring soil total nitrogen(TN), total phosphorus(TP) and total potassium(TK) in large area by using Hyperspectral Remote Sensing technology. Based on the combined methods of field investigation and indoor data from hyperspectral measurement(350-2 500 nm), the soils in four counties(zhaoyuan county, zhaozhou county, dumeng county, and lindian county), and daqing urban area, Heilongjiang province were studied and analyzed for the characteristics of soil spectrum and soil nutrient index. The variation in soil spectral reflectance was calculated in the form of first-order differential(R)′, reciprocal(1/R), reciprocal first-order differential(1/R)′, logarithm(log R) and so on. Then the estimating models of TN, TP and TK were established by unary linear regression(ULR), multivariate linear regression(MLR) and partial least squares(PLSR), and calibration model is verified by independent samples. The results showed that the optimum absorption bands of TN, TP and TK were TN(802 nm, 1 108 nm), TP(784 nm, 1 085 nm), TK(1 079 nm, 1 578 nm), respectively, the precision of partial least squares(PLSR) was higher than that of Multivariate linear regression(MLR) model and unary linear regression model(ULR), which were TN(R2 = 0.831, RMSE = 2.506 g/kg), TP( R2 = 0.687, RMSE = 0.844 g/kg), TK(R2 = 0.832, RMSE = 0.097 g/kg). The prediction accuracy of TN and TK was higher, while the prediction result of TP was relatively lower, but it can also be used for rough estimation. Meanwhile, MODIS images were used to map the concentrations of TN, TP and TK in soil. This study confirmed that hyperspectral technology combined with specific algorithms can better predict the concentrations of TN, TP and TK in soils with larger differences, and the visualization of predictive information can be realized. It is of great practical significance for real-time and rapidly monitoring large-scale changes in soil environment, predicting the trend of soil information changes, monitoring ecological environment, establishing soil nutrient database in China and reducing the monitoring cost of soil composition. [ABSTRACT FROM AUTHOR]

Objective: To analyze the expression and prognostic value of BTG/Tob antiproliferative (APRO) protein family in gastric cancer based on big data mining. Methods: The mRNA expression levels of six members of this family in gastric cancer tissues were analyzed via the Oncomine database. Moreover, the Kaplan-Meier database was used to evaluate the effect on overall survival (OS) of patients with gastric cancer. Results: Compared with the normal gastric tissue, BTG2 expression was lower in gastric cancer tissue, BTG3 expression was upregulated in intestinal gastric cancer tissue, but downregulated in total gastric cancer tissue. Patients with lower BTG3 expression had a shorter overall survival; gastric cancer patients with 5-fluorouracil based adjuvant chemotherapy had a worse prognosis in low BTG2 expression group. Conclusions: mRNA expression of BTG2 and BTG3 in gastric cancer and normal gastric tissues were significantly different. Patients with lower BTG3 expression had a poor prognosis. In addition, BTG2 may be involved in the sensitivity of 5-fluorouracil based adjuvant chemotherapy in gastric cancer patients. [ABSTRACT FROM AUTHOR]

Objective To determine the chemical compositions of volatile oil extracted from Menthae Haplocalycis Herba (mint) collected during different harvest periods by using headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry (HS/SPME-GC-MS). Methods The volatile oils were extracted by the method of headspace solid phase micro-extraction, then the chemical compositions were determined by using GC-MS and quantified by the area normalization method. Results A total of 47 compositions were detected in Menthae Haplocalycis Herba in mature stage, and 12 of those had been identified with the total content to be 78.23%. By comparing with the relative amount of menthone, l-limonene and l-menthol extracted from the herbal medicine samples collected during different harvest periods, which are the key components in biosynthesis pathway of the herb, the preliminary determination of the best time to harvest was September. Conclusion The effective and rapid method for the determination of volatile oils provided basis for studying the dynamic changes of the chemical compositions of volatile oil extracted from Menthae Haplocalycis Herba and the proper time to harvest. [ABSTRACT FROM AUTHOR]

Extreme heat events caused by climate change have seriously threatened the sustainable humanenvironment system development. It has become the frontier of integrated geography to scientifically assess the comprehensive impact of heat waves on the urban system and to provide stakeholders with decision support services to cope with extreme heat. This study constructed an "exposure-susceptibility-adaptive capacity" framework for urban heat vulnerability and an early warning index system based on the perspective of the humanenvironment system. We then proposed key early warning technologies, including an urban heat index model, multi-subject adaptive capacity coupling technology, and a multi-group vulnerability assessment criteria library. Taking urban diversified groups and urban administrators as the service target, we designed the urban heat vulnerability early warning system. The system mainly comprises a mobile application that provides users with an interactive interface, and a dedicated management backend. The mobile application has four main functions: Urban heat index forecast, Crowd heat vulnerability risk warning service, Outdoor work guidance service, and Public facility-assisted adaptation and decision support menu. The layer data and the warning message are mainly handled by the dedicated management backend. The system provides hourly location-based heat vulnerability warnings and targeted healthy living tips for tourists, the elderly, children, and people with heat-sensitive conditions. Additionally, the system can provide a scientific basis for communities to improve their adaptive capacity to heat waves. As a pilot, the system was deployed in Xiamen City to provide personalized support services for healthy living in hot weather to residents and communities. In September 2021, the "Urban Heat Index" module was officially launched on the "Zhi Tian Qi" public meteorological service platform of the Fujian Province. The research perspective and methodology, based on a multiscale vulnerability framework, provide an effective method to dynamically and finely characterize the impacts of extreme natural hazards. The research results support urban multi-stakeholders in managing production and life during hot weather and help authorities develop targeted disaster prevention and mitigation plans for specific areas. Moreover, the findings provide a scientific reference for planning departments to improve and optimize the spatial allocation of emergency resources. [ABSTRACT FROM AUTHOR]

In this study, the main research institutions, literature, patents, and standards of tilapia quality safety and nutritional quality from 2017 to 2022 were statistically analyzed. It was found that in recent years, there have been many studies on tilapia in the aspects of biohazard detection, pesticide and veterinary drug residue detection, heavy metal detection, and quality changes caused by different conditions. However, research on biotoxins, risk assessment of hazard factors, analysis of functional nutrition factors, and quality evaluation and grading of tilapia remains limited. At this stage, it is recommended that efforts be made to strengthen the development of a comprehensive indicator system for tilapia quality safety and nutritional quality and to establish and enhance relevant standards to bolster the research and standard system for tilapia, thereby improving the proactive prevention and control capabilities against risks in the international market. This study clarified the current research status, development trends, and future focus areas regarding tilapia quality safety and nutritional quality, offering valuable references for researchers to grasp the research foundation and directions. [ABSTRACT FROM AUTHOR]