Salmonella is one among the most important biological contaminants in drinking water that possess safety hazards to human life. Faecal contamination of the water, indirectly from the household sewage discharge, municipal sewage etc. attributes to the repeated detection of Salmonella in water. This study aimed to investigate the occurrence of Salmonella and physico- chemical quality evaluation of samples of water collected from food retail outlets of Thrissur and Kollam districts. A total of 50 water samples (25 each from Thrissur and Kollam districts) used for cooking purpose were collected over a period of six months, March to August 2023. Water samples were subjected to comparative evaluation of physico-chemical qualities viz., pH, turbidity, total dissolved solids (TDS) and hardness. Collected water samples were examined for Salmonella spp. by conventional culture method and PCR. Genus specific and virulence genes of the isolates were detected using polymerase chain reaction. The occurrence of Salmonella spp. in samples of water collected from Thrissur was 24 per cent whereas in Kollam district it was only four per cent. The overall occurrence of Salmonella spp. in samples of water collected from both districts was 14 per cent. Physico-chemical parameters of water samples viz., pH, turbidity, total dissolved solids and hardness were within the BIS prescribed standards. The molecular characterisation of Salmonella spp. detected 16S rRNA in all isolates but invA and spvA genes were detected only in 14.28 per cent of the isolates. Hence proper disinfection of water and food sanitation in the retail outlets will help to minimize the risk of foodborne pathogens Keywords: Salmonella, water, physico-chemical quality, food retail outlets

The classical objective methods of assessing video quality used so far, apart from their advantages, such as low costs, also have disadvantages. The need to eliminate these defects results in the search for better and better solutions. This article proposes a video quality assessment method based on machine learning using a linear regression model. A set of objective quality assessment metrics was used to train the model. The results obtained show that the prediction of video quality based on a machine learning model gives better results than the objective assessment based on individual metrics. The proposed model showed a strong correlation with the subjective user assessments but also a good fit of the regression function to the empirical data. It is an extension and improvement of the efficiency of the classical methods of objective quality assessment that have been used so far. The solution presented here will allow for a more accurate prediction of the video quality perceived by viewers based on an assessment carried out using a much cheaper, objective method.

In this study, the composition and structure of the macrobenthic community in the Ulungu River Basin was investigated and the water quality status of the basin was evaluated. In May and August 2022, and October 2023, the macrobenthic and water environmental factors at 11 sample sites in the basin were investigated, and the water quality of the basin was evaluated by the Shannon–Wiener index, FBI, and BMWP index. A total of 6101 macrobenthic organisms were collected; these organisms belonged to 3 phyla, 7 classes, 14 orders, 57 families, and 117 genera. Arthropod species accounted for the largest number of species (87.9%). A total of nine dominant species were found: <i>Micronecta</i> sp., <i>Eukiefferiella</i> sp., <i>Baetis</i> sp., <i>Polypedilum</i> sp., <i>Saetheria</i> sp., <i>Ephemerella</i> sp., <i>Limnodrilus</i> sp., <i>Ephemera</i> sp., and <i>Hydropsyche</i> sp. At the temporal level, the average density and biomass of macrobenthos were in the order of August > October > May; at the spatial level, the average density was greater in the tributaries than in the main stream, and the average biomass was greater in the main stream than in the tributaries. The mean values of the Shannon—Wiener index and Margalef richness index were as follows: August > October > May at the temporal level; the mean values of the Pielou evenness index were as follows: May > October > August at the temporal level. At the spatial level, the overall mean value of each diversity index indicated that the tributaries had larger diversity indices than the main stream. The water quality evaluation results revealed that the overall water quality level of the Ulungu River Basin ranges from light pollution to poor quality. Human interference activities greatly impact the water quality of the basin. To restore the ecology of the basin, it is necessary to strengthen the management and control of pollution sources.

This study explored the differences in the chemical and elemental composition, anti-nutritional factors, and nitrate content of cassava tender shoots (CTS) pickled vegetables under various traditional processes, such as Kimchi (KIM), sprouts pickles (SPP), vegetable pickled in sauce (SP), olives pickles (OP), hot Kimchi (HK) and salted pickles (SAP), using sensory evaluation, the index of nutritional quality (INQ), and principal component analysis (PCA). The aim was to identify the optimal process for producing high-quality CTS pickled vegetables. Results indicated that different pickling processes significantly affect the quality of CTS pickled vegetables. SPP had the highest protein content at 35.29 g/100 g, while SAP had relatively lower chemical composition. The mineral content in the CTS pickled vegetables decreased to varying degrees, with SPP having the most significant decrease (71.91% in Mn content, 70.72% in Zn, 59.20% in K, and 60.84% in Mg). The cyanide content of CTS pickled vegetables ranged from 32.62 mg/kg to 82.41 mg/kg, while tannin content ranged from 1.07 g tannic acid/100 g to 2.33 g tannic acid/100 g, with nitrate content lower than the national standard at 0.37 mg/kg to 1.02 mg/kg. Sensory evaluation showed that KIM had satisfactory freshness, texture, and appearance, ranking the highest among all. INQ evaluation indicated that SAP, KIM, and HK had higher nutritional value. PCA analysis showed that the cumulative contribution rate of the first three principal components was 83.949%, and the overall score showed that KIM, OP and HK had higher quality. After comprehensive evaluation of sensory evaluation, INQ evaluation, and PCA analysis, KIM using the pickle-making process was determined to be the best method, followed by HK and SAP.

Cultivated land is the most important natural resource for human survival and development. The quality of cultivated land is closely related to grain output, and whether it can guarantee stable food supply is directly related to national food security. Cultivated land quality evaluation is an effective tool for understanding and mastering cultivated land quality. However, few studies have applied bibliometrics to quantitatively and systematically analyze this field. We used VOSviewer 1.6.19 and CiteSpace 6.3.1 software to visually analyze and construct 2478 documents related to cultivated land quality evaluation retrieved from the Web of Science core collection database from 2000 to 2023. Results show that cultivated land quality evaluation is still a popular research field. The collaboration ability among authors is weak and the distribution of institutions and countries publishing in this field is very uneven. In addition, the relevant research has been published in a variety of journals such as agriculture, environment, ecology, and computer technology. The research content is becoming more and more interdisciplinary. Keywords such as “Soil quality”, “Swat”, “Remote sensing”, “Heavy metals” and “Ecosystem services” have become hot topics in this field. In the future, it is necessary to further deepen the connotation of cultivated land quality, develop a long time series dynamic model of cultivated land quality evaluation and monitoring, and enhance the transformation of research results into practical applications.

Currently, China’s river water quality evaluation adopts the “Environmental Quality Standards for Surface Water”, while the seawater quality evaluation uses the “Seawater Quality Standard”. However, estuarine areas, where rivers meet the sea, do not have evaluation standards, and most often, the “Seawater Quality Standard” is applied. At present, the water quality in the estuary area sometimes exceeds the corresponding seawater quality standards, even though the quality of the surface water does not exceed surface water environmental quality standards and the quality of the seawater before mixing also meets the seawater quality standards. This paper proposes a dynamic evaluation standard based on the salinity of estuarine water and uses this standard to evaluate the water quality in estuaries, thus solving the abovementioned issue. The implementation of this method is simple and effective. Taking the Pearl River Estuary as an example, this paper introduces the dynamic standard evaluation method for water quality in the Pearl River Estuary. Compared to the existing seawater quality standards implemented in estuaries, this dynamic evaluation standard can assess the water quality in estuaries more accurately and provide a reference for water quality evaluation methods in estuaries.

Pingliang City has a complex topography and diverse soil types. To realize the improvement of soil according to local conditions and the reasonable and sustainable use of soil resources, an evaluation of soil quality in Pingliang City was carried out, based on the soil distribution situation in Pingliang City, adopting a method combining fuzzy mathematics and cluster analysis of the main evaluation factors, such as soil organic matter, topsoil depth, soil erosion intensity, soil moisture regime, effective soil thickness, soil texture, soil profile structure, soil nutrient status and topographical parts, to carry out a comprehensive evaluation. A comprehensive evaluation of soil quality was conducted in seven counties under the jurisdiction of Pingliang City, and the evaluation results were compared and analyzed against the national standard, “Cultivated land quality grade”, to provide a basis for the selection of scientific soil improvement methods. The results of the arable land quality grades indicate that the quality of farmland in Pingliang City is divided into three to ten grades, and the average quality grade of farmland is 6.83, which is in the middle–lower level, and the overall grade distribution shows the characteristics of low in the middle and high in the east and west. The results of fuzzy mathematics combined with cluster analysis indicated the following trends in soil quality for the 12 soil genera: Chuan black gunny soil > yellow moist soil > sandy soil > silt soil > mulching helilu soil> loessal soil> loamy soil > slope loessal soil > arenosol > tillage leaching gray cinnamon soil > calcareous gray cinnamon soil > red clay soil. The results of the combination of fuzzy mathematics and clustering were significantly correlated with the results of the evaluation of the soil quality of arable land; the correlation coefficient was 0.884. This indicates that the method can accurately and objectively review the advantages and disadvantages of arable land soil and can be effectively applied to the evaluation of the soil quality of agricultural soils in other regions. It is a complement to the existing evaluation of the soil quality of arable land and at the same time provides a reference for the improvement of soil quality in agricultural regions.

[Objective] In order to solve the issue of excessive redundant information in near-infrared spectroscopy, enhance the accuracy of wine quality evaluation models, a rapid and non-destructive method was established for wine quality evaluation. [Methods] A wine quality evaluation model was proposed based on competitive adaptive reweighting sampling method for feature wavelength screening and extreme learning machine improved by whale optimization algorithm. Various feature wavelength screening methods such as competitive adaptive reweighting sampling was used, and the most suitable method for wine spectral feature wavelength screening was determined. In response to the problem of initial value and hidden layer bias in ELM, the whale optimization method was used to optimize the initial value and hidden layer bias of ELM, and an wine quality evaluation model based on extreme learning machine improved by whale optimization algorithm was constructed. [Results] Compared with GA-ELM, PSO-ELM, and the traditional ELM model, the accuracy of WOA-ELM was the highest, reaching 0.944 5, which was better than GA-ELM (0.929 0), PSO-ELM (0.906 1) and traditional ELM (0.817 7). [Conclusion] The parameters of the ELM model optimized by intelligent algorithms can effectively improve the accuracy of wine quality evaluation.

[Objective] In order to accurately evaluate the soil quality characteristics of the dip/anti-dip erosion slope in the karst trough valley screen out suitable soil quality evaluation methods and explore the obstacle factors limiting soil quality in this area. [Methods] Five typical land use types (forest land, grassland, bare land, corn land, pepper land) were selected as the research objects in Qingmuguan Karst trough Valley of Chongqing, and the minimum data set (MDS) was established by principal component analysis combined with Norm value. The nonlinear soil quality evaluation method and membership function were used to evaluate the soil quality of the diplanti-dip erosion Slope and down-slope in the karst trough valley. [Results] (1) MDS of soil quality evaluation indexes in karst troughs valleys included capillary water capacity, capillary porosity and total phosphorus. (2) According to the nonlinear soil quality evaluation method, the soil quality of anti-dip erosion slope (0.519) was better than that of dip erosion slope (0.451). The soil quality of anti-dip erosion slope forest land was the best (0.653), and that of pepper field was the worst (0.426). (3) The coefficient of determination (R2) of the nonlinear evaluation method was higher than the membership function in the dip erosion slope and the anti-dip erosion slope, so the non-linear scoring model was more suitable for the karst trough valley. (4) There were significant differences in soil quality barrier factors, and only total nitrogen was the common barrier factor. [Conclusion] Appropriately increasing grassland and forest cover can improve soil quality in karst trough and valley area. The results of this study can provide basis for soil quality control and rational fertilization of slope erosion along/against slope in karst trough valley according to local conditions.

This paper analyzes the connotation and essence of marine economy with high-quality development. Combined with the actual construction of powerful marine economy in Zhejiang Province, it constructs an evaluation system with “quality efficiency of marine economic development-marine innovation driving ability-external development level-marine ecological environment quality-social sharing degree” as the benchmark layer, and uses the entropy method to determine the index weight. This paper empirically analyzes the high-quality development level of Zhejiang marine economy from 2010 to 2020, and analyzes the internal relationship between each subsystem and the high-quality development of marine economy. The results showed that: The five subsystems were ranked in the order of external development level > quality efficiency of marine economic development > social sharing degree > marine innovation driving ability > marine ecological environment quality.During the whole evaluation period from 2010 to 2020, the evaluation results of high-quality development level of marine economy in Zhejiang Province showed a steady improvement trend. From 2010 to 2015, the quality and efficiency of sub-system marine economic development, marine innovation driving ability and social sharing degree all showed a trend of rapid improvement. After 2015, the external development level became the first driving force to improve the comprehensive evaluation results.