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Precisely delineating the spatiotemporal heterogeneity of water conservation services function (WCF) holds paramount importance for watershed management. However, the existing assessment techniques exhibit common limitations, such as utilizing only multi-year average values for spatial changes and relying solely on the spatial average values for temporal changes. Moreover, traditional research does not encompass all WCF values at each time step and spatial grid, hindering quantitative analysis of spatial heterogeneity in WCF. This study addresses these limitations by utilizing an improved water balance model based on ecosystem type and soil type (ESM-WBM) and employing the EFAST and Sobol’ method for parameter sensitivity analysis. Furthermore, a space–time cube of WCF, constructed using remote-sensing data, is further explored by Emerging Hot Spot Analysis for the expression of WCF spatial heterogeneity. Additionally, this study investigates the impact of two core parameters: neighborhood distance and spatial relationship conceptualization type. The results reveal that (1) the ESM-WBM model demonstrates high sensitivity toward ecosystem types and soil data, facilitating the accurate assessment of the impacts of ecosystem and soil pattern alterations on WCF; (2) the EHSA categorizes WCF into 17 patterns, which in turn allows for adjustments to ecological compensation policies in related areas based on each pattern; and (3) neighborhood distance and the type of spatial relationships conceptualization significantly impacts the results of EHSA. In conclusion, this study offers references for analyzing the spatial heterogeneity of WCF, providing a theoretical foundation for regional water resource management and ecological restoration policies with tailored strategies.

Integrated rice–fish farming, an agricultural practice that combines cultivating rice and breeding fish in the same field, has attracted widespread attention. However, there is limited research on how the rice–carp coculture impacts the community structure of phytoplankton and microzooplankton in paddy water. This study employed eDNA metabarcoding sequencing to analyze the composition of phytoplankton and microzooplankton in a rice monoculture system (RM) and a rice–carp coculture system (RF). Following annotation, we identified 9 phyla, 89 families, 275 genera, and 249 species of phytoplankton, along with 20 phyla (or subphyla and classes), 85 families, 222 genera, and 179 species of microzooplankton. The alpha diversity indices revealed significantly higher richness, diversity, and evenness in the RF group compared to the RM group during grain-filling stage. Principal coordinates analysis (PCoA) demonstrated notable differences in the phytoplankton and microzooplankton compositions between the two groups across various rice growth stages. Composition analysis showed that rice–carp coculture increased the relative abundance of dominant phytoplankton phyla such as Bacillariophyta, Chrysophyta, and Euglenophyta while decreasing that of Cryptophyta. In microzooplankton, the coculture resulted in an increased abundance of Intramacronucleata (subphylum) and a decrease in Conoidasida (class). In conclusion, the rice–carp coculture enhances the diversity of plankton, particularly during the grain-filling stage, and simultaneously alters the composition and abundance of dominant plankton species in the paddy water. These findings enhance understanding of the broader impacts of integrated rice–carp farming on agricultural ecosystems, emphasizing alterations in the diversity and composition of aquatic microorganisms

Aquaculture, the world’s fastest-growing food production sector, is critical for addressing food security concerns because of its potential to deliver high-quality, nutrient-rich supplies by 2050. This review assesses the effectiveness of CRISPR/Cas9 genome editing technology in enhancing desirable traits in fish species, including growth rates, muscle quality, disease resistance, pigmentation, and more. It also focuses on the potential effectiveness of the technology in allowing precise and targeted modifications of fish DNA to improve desirable characteristics. Many studies have reported successful applications of CRISPR/Cas9, such as knocking out reproductive genes to control reproduction and sex determination, enhancing feed conversion efficiency, and reducing off-target effects. Additionally, this technology has contributed to environmental sustainability by reducing nitrogen-rich waste and improving the nutritional composition of fish. However, the acceptance of CRISPR/Cas9 modified fish by the public and consumers is hindered by concerns regarding public perception, potential ecological impacts, and regulatory frameworks. To gain public approval and consumer confidence, clear communication about the editing process, as well as data on the safety and environmental considerations of genetically modified fish, are essential. This review paper discusses these challenges, provides possible solutions, and recommends future research on the integration of CRISPR/Cas9 into sustainable aquaculture practices, focusing on the responsible management of genetically modified fish to enable the creation of growth and disease-resistant strains. In conclusion, this review highlights the transformative potential of CRISPR/Cas9 technology in improving fish traits, while also considering the challenges and ethical considerations associated with sustainable and responsible practices in aquaculture.

Integrated rice–aquatic animal farming has become a vital strategy for enhancing food security. To assess the effects of integrated rice–giant river prawn (Macrobrachium rosenbergii) farming (IRPF) on agricultural ecosystems, we used 16S rRNA gene sequencing to analyze soil bacterial communities in comparison with traditional rice monoculture (RM). Our study revealed that the IRPF did not significantly affect the diversity of the soil bacterial community. However, during the initial culture stage, IRPF markedly increased the relative abundance of the phylum candidate division NC10 and the genus Candidatus Methylomirabilis, enhancing nitrogen-cycling-related functions within the bacterial community. Additionally, IRPF reduced the complexity and stability of these communities in the early to middle culture stages. While stochastic processes usually dominate the assembly of these communities, IRPF restricted bacterial migration and reduced the influence of these stochastic processes. Furthermore, IRPF had a significant impact on environmental factors within paddy soils, strongly correlating with shifts in bacterial communities, particularly through variations in soil nitrite concentration. In conclusion, the influence of IRPF on the bacterial community in paddy soils was primarily observed during the early and middle culture stages, and the impacts of IRPF on the soil bacterial community were primarily driven by environmental changes, especially soil nitrite concentration. These findings provide theoretical insights and a reference for understanding the microbiological impacts of different integrated rice–fish farming systems on agricultural ecosystems.

In this paper, three sorts of network indices for the weighted three-layered graph are studied through the methods of graph spectra theory combined with analysis methods. The concept of union of graphs are applied to design two sorts of weighted layered multi-fan composed graphs, and the accurate mathematical expressions of the network indices are obtained through the derivations of Laplacian spectra; furthermore, the asymptotic properties are also derived. We find that when the cardinalities of the vertices on a sector-edge-link tend to infinity, the indices of FONC and EMFPT are irrelevant with the number of copies of the fan-substructure based on the considered graph framework.

Cyprinus carpio is a significant freshwater species with substantial nutritional and economic value. Rice–carp co-culture represents one of its principal cultivation methods. However, in the system, the optimal farming density for carp and the impact of high stocking density on their muscle nutritional composition have yet to be explored. Thus, the objective of the current study was to investigate the influences of stocking density on the muscle nutrient profiles and metabolism of C. carpio in rice–fish co-culture systems. Common carp were cultured at three stocking densities, low density (LD), medium density (MD), and high density (HD), over a period of 60 days. Following this, comprehensive analyses incorporating physiological, biochemical, and multi-omics sequencing were conducted on the muscle tissue of C. carpio. The results demonstrated that HD treatment led to a reduction in the antioxidant capacity of C. carpio, while resulting in elevated levels of various fatty acids in muscle tissue, including saturated fatty acids (SFAs), omega-3 polyunsaturated fatty acids (n-3 PUFAs), and omega-6 polyunsaturated fatty acids (n-6 PUFAs). The metabolome analysis showed that HD treatment caused a marked reduction in 43 metabolites and a significant elevation in 30 metabolites, primarily linked to lipid and amino acid metabolism. Additionally, transcriptomic analysis revealed that the abnormalities in lipid metabolism induced by high-stocking-density treatment may be associated with significant alterations in the PPAR signaling pathway and adipokine signaling pathway. Overall, our findings indicate that in rice–fish co-culture systems, high stocking density disrupted the balance of antioxidant status and lipid metabolism in the muscles of C. carpio.

The Common Black Carp Strain (Cyprinus carpio var. baisenensis), known for its black skin, is commonly cultured in the integrated rice-agriculture (IRA) system in Guangxi province, China. This study aimed to compare the genetic diversity of three common carp strains/populations (Common Black Carp Strain, Huanghe, and Songpu) using resequencing data. The genome-based method reveals a significant difference (p < 0.05) in identified loci and SNP frequency (p < 1 × 10−6) between the Songpu (Sp) or mirror carp and Huanghe (Hh) new strain. Additionally, the Common Black Carp Strain (Bk) exhibits a higher number of Tajima’s D values, possibly due to its population size and mutations within its entire genome. The average value of population nucleotide diversity (π) for the Bk is 1.706 × 10−4 while the mean number for the Hh and Sp strains is 1.691 × 10−4 Heterozygosity analysis results indicate that the Bk has the highest F coefficient compared to the Sp and Hh hybrids. This suggests that the isolated population of the Bk may have experienced a decrease in population size as a result of environmental disturbances in the IRA system. PCA results further reveal that all individuals of the Bk, except for one, are clustered together, while individuals of the Hh form a separate group. On the other hand, Sp displays a distinct distribution pattern. The comparative study of the genetic diversity of the Bk provides baseline data on its genome makeup. Assessing genetic diversity and genetic structure is critical for fisheries management and the conservation of critically endangered fish species.

The rice–fish co-culture is an important model of carp farming in China; however, research on the dynamics and assembly of water bacterial communities in this system remains limited. Therefore, this study aimed to explore the dynamics and assembly of bacterial communities, as well as their correlation with environmental factors in paddy water. For these purposes, this study was divided into two groups: a rice–carp co-culture (WRC) group and a rice monoculture (WRM) group, with 20 rice fields in each group. After 60 days of farming, the concentrations of NH4+-N, NO2−-N, TN, and PO43− were significantly higher in the WRC group than those in the WRM group. Alpha diversity analysis showed that the Shannon index in the WRC group was significantly decreased compared with the WRM group. At the phylum level, the relative abundance of Actinobacteria significantly increased, while the relative abundance of Proteobacteria and Bacteroidetes significantly decreased in the paddy water of the WRC group. The neutral community model (NCM) indicated that a random process played a dominant role in the construction of bacterial communities in the two groups, and common carp cultivation increased migration rates, thereby affecting community assembly. The co-occurrence network displayed that common carp cultivation led to looser interactions between bacterial communities. In addition, the contents of nutrients significantly affected the abundance of bacteria in paddy water. In summary, carp cultivation decreased the diversity of bacteria and changed the relative abundance of dominant bacteria, thereby affecting the stability and assembly of bacterial communities.

The largemouth bronze gudgeon has experienced a sharp drop in its natural population and has been listed as a protected species in China. The frequent occurrence of ovarian development obstruction from stage III to IV has restricted artificial propagation. Due to lipids being a crucial factor for ovarian development, this study aimed to characterize the ovarian lipid profile at different development stages in largemouth bronze gudgeons. Using UPLC-MS/MS, 1353 lipids belonging to 46 subclasses were identified in ovaries from largemouth bronze gudgeons. The results showed that glycerolipids and glycerophospholipids were the dominant lipids during ovarian development. Lysophosphatidyl choline (LPC), phosphatidyl choline (PC), and phosphatidylserine (PS), as the crucial phospholipids for ovarian development, were significantly reduced from stage III to IV. This may be the main cause of ovarian development obstruction for largemouth bronze gudgeons. Meanwhile, the enrichment analysis revealed that lipid metabolites are present at different ovarian development stages. Glycerophospholipid, linoleic acid, and linolenic acid metabolism were significantly enriched at stage IV. This study shows the complete picture of the ovarian lipid composition profile, and also discovers that phospholipids may be the limiting factor for ovarian development; these findings offer a theoretical basis for the artificial propagation and release of the largemouth bronze gudgeon.

Common carp (Cyprinus carpio) is a freshwater fish commonly farmed in rice fields, yet there were few studies on the intestinal functions and microbial community structure of common carp in the rice–carp co-culture system. Therefore, this study aimed to explore the effects of different stocking densities on the growth, antioxidant status, and intestinal bacterial composition of common carp in this system. This study was divided into three different stocking densities, including low density (LD, 10 fish, 52.9 g/m2), medium density (MD, 20 fish, 105.8 g/m2), and high density (HD, 30 fish, 158.7 g/m2), with a culturing period of 60 days. The results indicated that HD treatment inhibited the growth of common carp, as evidenced by the reduced final weight, WG, and SGR. In serum, the TG content in the HD group and the Cor content in the MD group were significantly increased. Meanwhile, HD treatment induced oxidative stress, manifesting specifically as increased SOD and CAT activities in the intestine or serum while reducing Gpx, GSH, and T-AOC in the serum. The 16S rDNA analysis indicated that the Simpson and Shannon indices of intestinal microbiota in the HD group were significantly higher than those in the LD group. At the phylum level, Proteobacteria, Cyanobacteria, and Firmicutes were dominant microbial communities in two groups. In addition, there was a significant difference between the two groups in the abundances of Actinobacterota and Bifidobacterium. Based on growth performances, biochemical indicators, and microbial diversity in rice–carp co-culture, low density (52.9 g/m2) may be more suitable in the rice–carp co-culture systems. In summary, this study contributes to a better understanding of common carp response to different stocking densities in the rice–carp co-culture system.

The random movement of occupants in a high-speed railway station results in a more complex indoor environment. In this study, the indoor thermal environment and the thermal comfort in summer were investigated via field measurements and questionnaires in the waiting hall of a high-speed railway station. The results showed that there was an uneven horizontal temperature distribution in the area, and over 30% of the passengers were dissatisfied with the air conditioning system. In order to improve the control of the indoor temperature as well as reduce the energy consumption of the air conditioning system, an improved zonal control strategy and AMPC control optimization algorithm based on real-time people are proposed, and different control strategies are modeled and simulated using MATLAB/Simulink. It is concluded that the improved zonal control method proposed in this paper can save 28.04% of the fan energy consumption compared with the traditional control strategy.

In South China, the large quantity of rainfall in the pre-summer rainy season can easily lead to natural disasters, which emphasizes the importance of improving the accuracy of precipitation forecasting during this period for the social and economic development of the region. In this paper, the back-propagation neural network (BPNN) is used to establish the model for precipitation forecasting. Three schemes are applied to improve the model performance: (1) predictors are selected based on individual meteorological stations within the region rather than the region as a whole; (2) the triangular irregular network (TIN) is proposed to preprocess the observed precipitation data for input of the BPNN model, while simulated/forecast precipitation is the expected output; and (3) a genetic algorithm is used for the hyperparameter optimization of the BPNN. The first scheme reduces the mean absolute percentage error (MAPE) and the root mean square error (RMSE) of the simulation by roughly 5% and more than 15 mm; the second reduces the MAPE and RMSE by more than 15% and 15 mm, respectively, while the third improves the simulation inapparently. Obviously, the second scheme raises the upper limit of the model simulation capability greatly by preprocessing the precipitation data. During the training and validation periods, the MAPE of the improved model can be controlled at approximately 35%. For precipitation hindcasting in the test period, the anomaly rate is less than 50% in only one season, and the highest is 64.5%. According to the anomaly correlation coefficient and Ps score of the hindcast precipitation, the improved model performance is slightly better than the FGOALS-f2 model. Although global climate change makes the predictors more variable, the trend of simulation is almost identical to that of the observed values over the whole period, suggesting that the model is able to capture the general characteristics of climate change.

Berberine, a natural alkaloid found abundantly in various medicinal plants, exhibits antioxidative, anti-inflammatory, and lipid metabolism-regulatory properties. Nonetheless, its protective effects and the molecular mechanisms underlying liver injury in fish have not been fully elucidated. The aims of this study were to investigate the antioxidative, anti-inflammatory, and lipid metabolism-regulating effects of berberine against high-fat diet (HFD)-induced liver damage and to clarify the underlying molecular mechanisms. Tilapia were fed diets containing two doses of berberine (50 and 100 mg/kg diet) alongside high fat for 60 days. The results showed that berberine treatments (50 and/or 100 mg/kg) significantly reduced elevated aminotransferases, triglycerides (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-c) in the plasma. In the liver, berberine treatments significantly increased the expression of peroxisome proliferator-activated receptor α (pparα) and carnitine palmitoyltransferase 1 (cpt-1) genes, leading to a reduction in lipid accumulation. Meanwhile, berberine treatment suppressed lipid peroxidation formation and enhanced antioxidant capacity. Berberine upregulated the mRNA levels of erythroid 2-related factor 2 (nrf2) and its downstream genes including heme oxygenase 1 (ho-1) and glutathione-S-transferase (gstα). Additionally, berberine attenuated the inflammation by inhibiting the expression of toll-like receptor 2 (tlr2), myeloid differential protein-88 (myd88), relb, and inflammatory cytokines such as interleukin-1β (il-1β), tumor necrosis factor-α (tnf-α), and il-8. In summary, this study suggested that berberine offers protection against HFD-induced liver damage in tilapia via regulating lipid metabolism, antioxidant status, and immune response. This protective effect may be attributed to the modulation of the Nrf2, TLR2/MyD88/NF-κB, and PPARα signaling pathways.

Integrated rice-fish farming has emerged as a novel agricultural production pattern to address global food security challenges. Aiming to determine the optimal, scientifically sound, and sustainable stocking density of red claw crayfish (Cherax quadricarinatus) in an integrated rice-crayfish farming system, we employed Illumina high-throughput 16S rRNA gene sequencing to evaluate the impact of different stocking densities of red claw crayfish on the composition, diversity, function, and co-occurrence network patterns of soil bacterial communities. The high stocking density of red claw crayfish reduced the diversity and evenness of the soil bacterial community during the mid-culture stage. Proteobacteria, Actinobacteria, and Chloroflexi emerged as the most prevalent phyla throughout the experimental period. Low stocking densities initially boosted the relative abundance of Actinobacteria in the paddy soil, while high densities did so during the middle and final stages. There were 90 distinct functional groups identified across all the paddy soil samples, with chemoheterotrophy and aerobic chemoheterotrophy being the most abundant. Low stocking densities initially favored these functional groups, whereas high densities enhanced their relative abundances in the later stages of cultivation. Medium stocking density of red claw crayfish led to a more complex bacterial community during the mid- and final culture stages. The experimental period showed significant correlations with soil bacterial communities, with total nitrogen (TN) and total phosphorus (TP) concentrations emerging as primary factors contributing to the alterations in soil bacterial communities. In summary, our findings demonstrated that integrated rice-crayfish farming significantly impacted the soil microbiomes and environmental factors at varying stocking densities. Our study contributed to theoretical insights into the profound impact of integrated rice-crayfish farming with various stocking densities on bacterial communities in paddy soils.

The aim of this study was to assess the regional differences of Procambarus clarkii through analyzing gut microbiota in specimens from different areas in China. The P. clarkii were collected from ten integrated rice–crayfish farming systems locating across ten major producing areas as follows: Feixi (FX), Suqian (SQ), Yangzhou (YZ), Xuyi (XY), Qianjiang (QJ), Jianli (JL), Honghu (HH), Yueyang (YY), Changsha (CS), and Nanxian (NX). The composition of gut microbiota was assessed by analyzing 16S rRNA sequences. The PCoA results indicated significant differences in microbial community composition among the ten areas (R = 0.999, p = 0.001). The intestinal microbial diversity in P. clarkii cultured in rice fields from YY and CS exceeded that of other regions, with NX displaying the least diversity. At the phylum level, Proteobacteria were most abundant in HH, while Firmicutes showed increased relative abundances in FX and SQ, contrasted by lower relative abundances of Bacteroidetes in these areas. At the genus level, Ralstonia, Amedibacillus, Bacteroides, Anaerorhabdus, and Dysgonomonas were the dominant bacteria. The bacterial co-occurrence networks analysis revealed that the community structures in locations FX, SQ, XY, HH, and NX were comparatively simplistic, whereas those in the YZ, QJ, JL, YY, and CS regions displayed as more complex. In summary, the diversity and relative abundance of intestinal bacteria exhibits regional variability. These findings can offer theoretical data for evaluating the quality of P. clarkii aquaculture.

Proanthocyanidins (Pros), a natural polyphenolic compound found in grape seed and other plants, have received significant attention as additives in animal feed. However, the specific mechanism by which Pros affect fish health remains unclear. Therefore, the aim of this study was to investigate the potential effects of dietary Pro on common carp by evaluating biochemical parameters and multi-omics analysis. The results showed that Pro supplementation improved antioxidant capacity and the contents of polyunsaturated fatty acids (n-3 and n-6) and several bioactive compounds. Transcriptomic analysis demonstrated that dietary Pro caused an upregulation of the sphingolipid catabolic process and the lysosome pathway, while simultaneously downregulating intestinal cholesterol absorption and the PPAR signaling pathway in the intestines. Compared to the normal control (NC) group, the Pro group exhibited higher diversity in intestinal microbiota and an increased relative abundance of Cetobacterium and Pirellula. Furthermore, the Pro group had a lower Firmicutes/Bacteroidetes ratio and a decreased relative abundance of potentially pathogenic bacteria. Collectively, dietary Pro improved antioxidant ability, muscle nutrients, and the diversity and composition of intestinal microbiota. The regulation of lipid metabolism and improvement in muscle nutrients were linked with changes in the intestinal microbiota.

Solar power generation has great development potential as an abundant and clean energy source. However, many factors affect the efficiency of the photovoltaic (PV) module; among these factors, outdoor PV modules are inevitably affected by stains, thus reducing the power generation efficiency of the PV panel. This paper proposes a framework for PV module stain detection based on UAV hyperspectral images (HSIs). The framework consists of two stain detection methods: constrained energy minimization (CEM)-based and orthogonal subspace projection (OSP)-based stain detection methods. Firstly, the contaminated PV modules are analyzed and processed to enhance the data’s analytical capability. Secondly, based on the known spectral signature of the PV module, stain detection methods are proposed, including CEM-based stain detection and OSP-based stain detection for PV modules. The experimental results on real data illustrate that, in comparison with contrasting methods, the proposed method achieves stain detection results that closely align with known stain percentages. Additionally, it exhibits a fitting curve similar to the more maturely developed electroluminescence-based methods currently in use.

As the urgency to adopt renewable energy sources escalates, so does the need for accurate forecasting of power output, particularly for wind and solar power. Existing models often struggle with noise and temporal intricacies, necessitating more robust solutions. In response, our study presents the SL-Transformer, a novel method rooted in the deep learning paradigm tailored for green energy power forecasting. To ensure a reliable basis for further analysis and modeling, free from noise and outliers, we employed the SG filter and LOF algorithm for data cleansing. Moreover, we incorporated a self-attention mechanism, enhancing the model’s ability to discern and dynamically fine-tune input data weights. When benchmarked against other premier deep learning models, the SL-Transformer distinctly outperforms them. Notably, it achieves a near-perfect R2 value of 0.9989 and a significantly low SMAPE of 5.8507% in wind power predictions. For solar energy forecasting, the SL-Transformer has achieved a SMAPE of 4.2156%, signifying a commendable improvement of 15% over competing models. The experimental results demonstrate the efficacy of the SL-Transformer in wind and solar energy forecasting.

Red claw crayfish Cherax quadricarinatus has emerged as a highly significant and suitable species to be raised in integrated rice–aquatic animal farming systems. To optimize an integrated aquaculture and agriculture (IAA) system and ensure sustainable utilization and development of land resources, an IAA system combining rice cultivation with red claw crayfish culture was implemented to assess the impacts of rice–red claw crayfish co-culturing on the dynamics and assembly of bacterial communities in paddy soils. We established two experimental groups, each with eight replicates. We utilized 16S rRNA Illumina high-throughput sequencing to access the bacterial community composition and assembly in paddy soils. Red claw crayfish C. quadricarinatus cultivation did not significantly affect the alpha diversity of the bacterial community in the paddy field, but it obviously increased the relative abundances of the phyla Acidobacteriota and Pseudomonadota involved in organic matter degradation and nitrogen, phosphorus, and carbon cycling. Red claw crayfish cultivation could lead to more complex bacterial communities, increased bacterial resistance to disturbances, the promotion of niche differentiation, and increased competition intensity between bacterial communities during the mid-cultivation period. Nitrogen emerged as a critical factor influencing the bacterial community composition in paddy soil during the culture period, and the red claw crayfish cultivation affected the bacterial community by altering the ammonia concentration in the paddy soil. As the culture progressed, the assembly of the bacterial community in the paddy soil was predominantly driven by stochastic processes, and red claw crayfish cultivation accelerated the evolution of the bacterial community assembly towards a stochastic process. Our study offers valuable insights into the dynamic changes occurring in the composition and assembly of bacterial communities in paddy soils in response to red claw crayfish cultivation.

The snail Bellamya purificata is recognized as a potential bio-remediation species, and is commonly employed in polyculture to enhance resource utilization efficiency and realize culture environment regulation. In order to enrich the microbiome studies on elucidating the ecological effects of snail B. purificata farming, we assessed the effect of B. purificata farming activities, at varying stocking densities, on the algal and fungal communities in sediment. Four experimental groups were established in our study, each corresponding to a different stocking density: 0, 234.38, 468.75, and 937.5 g/m2, represented as CON, LD, MD, and HD, respectively. High-throughput sequencing based on ITS and 23S ribosomal RNA (rRNA) genes was employed to analyze the variations in algal and fungal communities under B. purificata farming activities at different stocking densities. B. purificata farming activities had no significant effect on the alpha diversities of fungal and algal communities, but significantly altered the compositions of fungal and algal communities in sediments, especially B. purificata farming activity at low stocking density. B. purificata farming activities at low stocking density could significantly increase the relative abundances of fungal genera Paraconiothyrium and Penicillium compared with the CON group. The promoting effect diminished with increasing density. B. purificata farming activities at low or medium stocking density also could enhance the relative abundances of algal genera Microchloropsis, Scenedesmus, and Auxenochlorella. Hence, B. purificata farming activity at low stocking density might be the optimum density to enhance resource utilization efficiency and minimize environmental pollution.

Dietary selenium (Se) is an essential component that supports fish growth and the immune system. This review attempts to provide insight into the biological impacts of dietary Se, including immunological responses, infection defense, and fish species growth, and it also identifies the routes via which it enters the aquatic environment. Dietary Se is important in fish feed due to its additive, antioxidant, and enzyme properties, which aid in various biological processes. However, excessive intake of it may harm aquatic ecosystems and potentially disrupt the food chain. This review explores the diverse natures of dietary Se, their impact on fish species, and the biological methods for eliminating excesses in aquatic environments. Soil has a potential role in the distribution of Se through erosion from agricultural, industrial, and mine sites. The research on dietary Se’s effects on fish immune system and growth can provide knowledge regarding fish health, fish farming strategies, and the health of aquatic ecosystems, promoting the feed industry and sustainable aquaculture. This review provides data and references from various research studies on managing Se levels in aquatic ecosystems, promoting fish conservation, and utilizing Se in farmed fish diets.

The substrate in the aquatic environment plays a crucial role in nutrient deposition and recovery for the growth of aquatic organisms. In order to optimize the culture medium of Procambarus Clarkii, culture media from different sources were selected in this study to explore their effects on the growth and immune performance of red swamp crayfish. The results showed that the weight gain rate (WGR), body length growth rate (BLGR) and specific growth rate (SGR) in group I2 were the highest, followed by group I1 and group I3. The WGR and SGR of crayfish in the I1 and I2 groups were significantly higher than those in the I3 group (p < 0.05). The activities of acid phosphatase (ACP), alkaline phosphatase (AKP) and superoxide dismutase (SOD) were the highest in group I2, followed by group I3, and the lowest in group I1. The expression trends in growth-related genes, nuclear hormone receptor (E75), molt-inhibiting hormone (MIH) and chitinase genes were similar, and the expression levels in the I2 group were higher than those in the I1 and I3 groups. It was noted that the expression levels of E75 and MIH genes in the I2 group were significantly higher than those in the I3 group (p < 0.05). α diversity analysis of 16S rRNA data showed that there was no statistically significant difference in the abundance of intestinal flora among the three culture substrate groups. The β diversity in the Xitangni group, crayfish Tangni group and Shuitangni group was significantly different. These changes in microbiota suggest that using different substrates to culture crayfish leads to differences in gut microbiota diversity. To sum up, the growth in crayfish and immune performance influenced by the culture substrate condition and aquatic breeding sediment substrates, rather than crab pool and paddy field pond sediment substrates, showed a better effect.

Stocking density is a crucial factor affecting productivity in aquaculture, and high stocking density is a stressor for aquatic animals. In this study, we aimed to investigate the effects of stocking densities on oxidative stress and energy metabolism in the gills of Cherax quadricarinatus under rice-crayfish farming. The C. quadricarinatus were reared at low density (LD), medium density (MD), and high density (HD) for 90 days. The results showed that the superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and malondialdehyde (MDA) levels were higher in the HD group than those in the LD group. Transcriptomic analysis revealed 1944 upregulated and 1157 downregulated genes in the gills of the HD group compared to the LD group. Gene ontology (GO) enrichment analysis indicated that these differentially expressed genes (DEGs) were significantly associated with ATP metabolism. KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis also showed that high stocking density resulted in the dysregulation of oxidative phosphorylation. Furthermore, high stocking density upregulated six lipid metabolism-related pathways. Overall, our findings, despite the limited number of samples, suggested that high stocking density led to oxidative stress and dysregulation of energy metabolism in the gills of C. quadricarinatus under rice–crayfish co-culture. Alteration in energy metabolism may be an adaptive response to adverse farming conditions.

Accurately estimating land surface temperature (LST) is a critical concern in thermal infrared (TIR) remote sensing. According to the thermal radiance transfer equation, the observed data in each channel are coupled with both emissivity and atmospheric parameters in addition to the LST. To solve this ill-posed problem, classical algorithms often require the input of external parameters such as land surface emissivity and atmospheric profiles, which are often difficult to obtain accurately and timely, and this may introduce additional errors and limit the applicability of the LST retrieval algorithms. To reduce the dependence on external parameters, this paper proposes a new algorithm to directly estimate the LST from the top-of-atmosphere brightness temperature in Landsat-9 two-channel TIR data (channels 10 and 11) without external parameters. The proposed algorithm takes full advantage of the adeptness of the ensemble learning method to solve nonlinear problems. It considers the physical radiance transfer process and adds the leaving-ground bright temperature and atmospheric water vapor index to the input feature set. The experimental results show that the new algorithm achieves accurate LST estimation results compared with the ground-measured LST and is consistent with the Landsat-9 LST product. In subsequent work, further studies will be undertaken on developing end-to-end deep learning models, mining more in-depth features between TIR channels, and reducing the effect of spatial heterogeneity on accuracy validation.

In recent years, convolutional neural networks (CNNs) have been widely used in the field of hyperspectral image (HSI) classification and achieved good classification results due to their excellent spectral–spatial feature extraction ability. However, most methods use the deep semantic features at the end of the network for classification, ignoring the spatial details contained in the shallow features. To solve the above problems, this article proposes a hyperspectral image classification method based on a Feature Embedding Network with Multiscale Attention (MAFEN). Firstly, a Multiscale Attention Module (MAM) is designed, which is able to not only learn multiscale information about features at different depths, but also extract effective information from them. Secondly, the deep semantic features can be embedded into the low-level features through the top-down channel, so that the features at all levels have rich semantic information. Finally, an Adaptive Spatial Feature Fusion (ASFF) strategy is introduced to adaptively fuse features from different levels. The experimental results show that the classification accuracies of MAFEN on four HSI datasets are better than those of the compared methods.

Restructuring Particle Swarm Optimization (RPSO) algorithm has been developed as an intelligent approach based on the linear system theory of particle swarm optimization (PSO). It streamlines the flow of the PSO algorithm, specifically targeting continuous optimization problems. In order to adapt RPSO for solving discrete optimization problems, this paper proposes the binary Restructuring Particle Swarm Optimization (BRPSO) algorithm. Unlike other binary metaheuristic algorithms, BRPSO does not utilize the transfer function. The particle updating process in BRPSO relies solely on comparison results between values derived from the position updating formula and a random number. Additionally, a novel perturbation term is incorporated into the position updating formula of BRPSO. Notably, BRPSO requires fewer parameters and exhibits high exploration capability during the early stages. To evaluate the efficacy of BRPSO, comprehensive experiments are conducted by comparing it against four peer algorithms in the context of feature selection problems. The experimental results highlight the competitive nature of BRPSO in terms of both classification accuracy and the number of selected features.

The onboard atomic frequency standard (AFS) is a crucial element of Global Navigation Satellite System (GNSS) satellites. However, it is widely accepted that periodic variations can influence the onboard AFS. The presence of non-stationary random processes in AFS signals can lead to inaccurate separation of the periodic and stochastic components of satellite AFS clock data when using least squares and Fourier transform methods. In this paper, we characterize the periodic variations of AFS using Allan and Hadamard variances and demonstrate that the Allan and Hadamard variances of the periodics are independent of the variances of the stochastic component. The proposed model is tested against simulated and real clock data, revealing that our approach provides more precise characterization of periodic variations compared to the least squares method. Additionally, we observe that overfitting periodic variations can improve the precision of GPS clock bias prediction, as indicated by a comparison of fitting and prediction errors of satellite clock bias.

“Alto2” is a new biomass sorghum variety, which has the characteristics of fast growth, high growth, and strong cadmium (Cd) resistance, so it has the application prospect of soil remediation plants. In order to reveal the Cd resistance mechanism of this plant and pave the way for genetic breeding and cultivation of efficient remediation plants in the future, in this research, through the determination of Cd content in various tissues of sorghum under Cd stress and the physicochemical response combined with RNA-Seq analysis, the mechanism of Cd resistance of “Alto2” was initially revealed. The results show biomass sorghum “Alto2” was mainly connected with aboveground and underground parts through the MAPK signaling pathway and plant hormone signaling pathway, and transmit stress signal in response to Cd stress. Chelase and metal-binding proteins may be the functional genes mainly responsible for Cd enrichment and transport and regulated by stress signals. However, the expression of aboveground transporters was not significant. This may be because Cd in biomass sorghum is mainly concentrated in the underground part and is enriched by the chelation of secondary metabolites from plant roots by the cell wall leading to inhibition of aboveground transporter expression. The results of this study indicate that the biomass sorghum “Alto2” on Cd has high resistance, but the lack of the aboveground enrichment of transportability requires further research to improve the Cd transportability of this plant.

Pelteobagrus fulvidraco is a freshwater fish commonly raised in rice fields, yet the optimal stocking density for this species remains unknown. Therefore, this study aimed to investigate the appropriate stocking density of P. fulvidraco in integrated rice–fish farming systems. Three different stocking densities––low density (LD, 125 g/m2), middle density (MD, 187.5 g/m2), and high density (HD, 250 g/m2)––were set up to evaluate P. fulvidraco’s growth performance, stress indices, immune function, antioxidant status, and lipid metabolism after 90 days of farming. The results indicated that HD treatment had a detrimental effect on P. fulvidraco’s growth parameters. HD treatment led to an increase in cortisol (Cor) and lactate (La) levels, but a decrease in glucose (Glu) content in serum. After 90 days of farming, an immune response accompanied by the increase of complement 3 (C3), C4, and immunoglobulin M (IgM) was observed in the HD group. Meanwhile, HD treatment induced oxidative stress and altered antioxidative status evidenced by the levels of catalase (CAT), glutathione peroxidase (Gpx), glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), and total antioxidant capacity (T-AOC) in serum or liver. Additionally, the lipid metabolism-related genes including lipoprotein lipase (lpl), peroxisome proliferators-activated receptor (pparα), carnitine palmitoyltransferase-1 (cpt-1), and sterol regulatory element binding protein-1 (srebp-1) were markedly downregulated in the HD and/or MD group after 90 days of farming. In conclusion, this study contributes to a better understanding of P. fulvidraco’s response to different stocking densities in integrated rice–fish farming systems. We suggest that the appropriate stocking density for P. fulvidraco in these farming systems should be below 250 g/m2, considering both fish growth and physiological responses.

This article presents the design and implementation of a 40 MHz crystal oscillator (XO) with low phase noise, based on the 55 nm CMOS process, for wireless transceiver systems, particularly those used in Wireless Local Area Network (WLAN). The proposed design employs a bandgap reference circuit that includes a start-up circuit and a low-voltage common-source common-gate current mirror, which ensures that the bandgap reference circuit is powered up effectively across all temperatures and process corners. A low-pass filter is also incorporated at the low dropout regulator (LDO) input to reduce the phase noise of the XO circuit. The experimental results demonstrate that the proposed design achieves a final phase noise of −164.36 dBc/Hz at 100 kHz offset frequency, with a power consumption of 0.444 mW. The test of start-up time is 0.718 ms and the compact chip area is 0.088 mm2. According to the simulation and test results, the final FOM value calculated in this paper is 209.93 dBc/Hz at 100 kHz offset.

The development trend of high shares of renewables and power electronics has increased the demand for new energy converters in the power system, but there is a lack of systematic research on the stability of different types of converters when transmitting power, which is worth exploring in depth. In this study, the power transfer capabilities of grid-forming and grid-following converters are investigated separately through an equivalent circuit diagram and phasor diagram when connected to the grid, and a quantitative relationship between converters’ power transmission limit and short circuit ratio under static stability conditions is obtained, leading to the conclusion that, in terms of power transmission, grid-forming converters are more suitable for weak grids with high damping and low inertia, whereas grid-following converters are more suitable for strong grids with high inertia. The conclusions are further verified by constructing the converter grid-connected models for different grid strengths through the PLECS simulation platform and the real-time simulation RTBOX1 and F28379D launchpad platform.

A kind of multiscale β-sialon grain-reinforced Al2O3 matrix composite ceramic tool material, named ASN, was prepared and studied. For the ASN, β-sialon (molecular formula: Si4Al2O2N6) was synthesized in situ by a hot-pressing and solid-solution reaction process. A total of six samples were prepared at varying sintering temperatures and holding times under vacuum conditions. The solid solution reaction mechanism of β-sialon, the phase composition, mechanical properties, microstructure, and strengthening and toughening mechanisms of the composite ASN were investigated. As a result, within the experimental parameters, an optimal ASN tool material was obtained under a pressure of 32 MPa and at a temperature of 1550 °C for 20 min. The tested mechanical properties of the optimal sample were as follows: flexural strength 997 ± 59 MPa, fracture toughness 6.4 ± 0.3 MPa·m1/2, Vickers hardness 18.2 ± 0.4 GPa, and relative density 98.1 ± 0.2%. According to crystal defect theory, the solid solution reaction mechanism of in-situ-synthesized β-sialon in an Al2O3 matrix involves a double mechanism of unequivalence (or hetero-valence) and interstitial filling. The multiscale β-sialon grains mainly consisted of four grains, which were elongated β-sialon grains with a diameter of 0.3–0.4 μm and an aspect ratio of 6–9, elongated β-sialon grains with a diameter of 70 nm and an aspect ratio of 10, β-sialon whiskers with a diameter of 0.2 μm and an aspect ratio of 12–15, and intragranular β-sialon whiskers with a diameter of 70 nm. The mechanical properties were improved due to strengthening and toughening mechanisms, such as mixed structure mode (intergranular and transgranular), elongated grain pullout, interface bonding, crack reflection, pinning, and bridging.

High environmental hydrogen peroxide (H2O2) has been demonstrated to be toxic for fish. However, the response mechanism of fish to chronic H2O2 exposure is not yet well understood. Therefore, this study aimed to investigate the alteration in ion transport in gills and analyzed the potential response mechanism after chronic H2O2 exposure. The common carps were exposed to 0, 0.25, 0.50, and 1.00 mM of H2O2 for 14 days. The histopathological evaluation results indicated that H2O2 exposure caused incomplete gill filament structure. In the plasma, H2O2 exposure suppressed the potassium (K+) concentration but increased sodium (Na+) concentration. In the gills, the calcium (Ca2+) level was raised, but the K+ and chlorine (Cl−) levels were decreased after H2O2 exposure. After 14 days of exposure, H2O2 prompted the activities of Ca2+/Mg2+-ATPase and H+/K+-ATPase but suppressed Na+/K+-ATPase activity in the gills. Gene transcription analysis showed that the ion-regulation-related genes including nkaa and rhbg were downregulated after H2O2 exposure. In addition, H2O2 exposure upregulated the mRNA levels of cam and camk II, indicating that the Ca2+ singling pathway was activated. In conclusion, our data showed that chronic H2O2 exposure altered gill structure and disturbed ion transport, which further negatively affected the equilibrium of ions and osmotic pressure.

Microfilaments and microtubules, two crucial structures of cytoskeletal networks, are usurped by various viruses for their entry, egress, and/or intracellular trafficking, including the Rabies virus (RABV). Intermediate filaments (IFs) are the third major component of cytoskeletal filaments; however, little is known about the role of IFs during the RABV infection. Here, we identified the IF protein desmin as a novel host interactor with the RABV matrix protein, and we show that this physical interaction has a functional impact on the virus lifecycle. We found that the overexpression of desmin facilitates the RABV infection by increasing the progeny virus yield, and the suppression of endogenous desmin inhibits virus replication. Furthermore, we used confocal microscopy to observe that the RABV-M co-localizes with desmin in IF bundles in the BHK-21 cells. Lastly, we found that mice challenged with RABV displayed an enhanced expression of desmin in the brains of infected animals. These findings reveal a desmin/RABV-M interaction that positively regulates the virus infection and suggests that the RABV may utilize cellular IFs as tracks for the intracellular transport of viral components and efficient budding.

To optimize the integrated multi-trophic aquaculture (IMTA) model, improve the efficiency of resource utilization, and reduce environmental pollution, Bellamya purificata, as a potential bioremediation species, was studied to investigate the effect of B. purificata culture on the dynamics and assembly of bacterial communities in sediment. Four experimental groups were established at four different densities: 0, 234.38, 468.75, and 937.5 g/m2 (represented as CON, LD, MD, and HD, respectively). Each group was with three replicates. The 16S ribosomal RNA (rRNA) high-throughput sequencing was used to evaluate the composition, function, and assembly of bacterial communities in sediment. B. purificata cultivation significantly altered the composition and function of the bacterial communities in sediment; at high stocking density, it significantly decreased anaerobic and increased aerobic organic matter decomposition, whereas at low stocking density, it decreased the number of bacteria involved in sulfate reduction and inhibited the denitrification process. B. purificata decreased direct competition and promoted collaboration or niche sharing in bacterial communities, especially at the high stocking density. Moreover, B. purificata cultivation resulted in greater changes in the environmental factors. Variations in dissolved oxygen, pH, total nitrogen, nitrate, and nitrite levels were closely related to the altered composition and function of the bacterial communities. Stochastic processes dominated the bacterial community assembly in the sediment and B. purificata cultivation had limited impacts on the bacterial community assembly. The study provided a reference for the dynamics and assembly of bacterial communities in sediment with different densities of B. purificata cultivation and we hope that the findings will provide a theoretical reference for the optimization of IMTA and improve management strategies for B. purificata polyculture.

An unprecedented city-wide lockdown took place in Shanghai from April to May 2022 to curb the spread of COVID-19, which caused socio-economic disruption but a significant reduction of anthropogenic emissions in this metropolis. However, the ground-based monitoring data showed that the concentration of ozone (O3) remained at a high level. This study applied Tropospheric Monitoring Instrument (TROPOMI) observations to examine changes in tropospheric vertical column density (VCD) of nitrogen dioxide (NO2) and formaldehyde (HCHO), which are precursors of O3. Compared with the same period in 2019–2021, VCDs of NO2 and HCHO decreased respectively by ~50% and ~20%. Multiple regression analysis showed that the lockdown effect played a dominant role in this dramatic decline rather than meteorological impacts. Using the exponentially-modified Gaussian method, this study quantified nitrogen oxides (NOX) emission in Shanghai as 32.60 mol/s with a decrease of 50–80%, which was mainly contributed by the transportation and industrial sectors. The significant reduction of NOX emission in Shanghai is much higher than that of volatile organic compounds (VOCs), which led to dramatic changes in formaldehyde-to-nitrogen dioxide ratio (HCHO/NO2, FNR). Thus, when enforcing regulation on NOx emission control in the future, coordinately reducing VOCs emission should be implemented to mitigate urban O3 pollution.

Composite structures can be designed with specific parameters for efficient sound absorption in specific frequency bands; however, determining the optimal parameters and topology to maximize sound absorption is a computationally challenging task. In this work, a semi-empirical model is constructed to predict the sound absorption performance of composite structures consisting of open-cell foam and perforated plates. The calculated results of the semi-empirical model are in good agreement with the experimental results carried out in the B and K tube impedance measurement system. The parameters such as perforation ratio, plate thickness, air gap, etc., of the composite structure within limited thickness were optimized by using a genetic algorithm (GA) to improve the sound absorption coefficient at a lower frequency band. The calculation and experimental results show that when the thickness is fixed, the peak sound absorption frequency can be reduced by 400 Hz; on the contrary, with the goal of broadening the sound absorption frequency band, the optimized composite structure can widen the sound absorption frequency band by 55.38%. The results of this work have potential engineering applications for the calculation of the sound absorption of porous materials and perforated plate composite structures and their optimal design, particularly when the total volume or total weight of the sound-absorbing material is strictly limited.

Coronary vessel layer structure may have a considerable impact on plaque stress/strain calculations. Most current plaque models use single-layer vessel structures due to the lack of available multilayer segmentation techniques. In this paper, an automatic multilayer segmentation and repair method was developed to segment coronary optical coherence tomography (OCT) images to obtain multilayer vessel geometries for biomechanical model construction. Intravascular OCT data were acquired from six patients (one male; mean age: 70.0) using a protocol approved by the local institutional review board with informed consent obtained. A total of 436 OCT slices were selected in this study. Manually segmented data were used as the gold standard for method development and validation. The edge detection method and cubic spline surface fitting were applied to detect and repair the internal elastic membrane (IEM), external elastic membrane (EEM) and adventitia–periadventitia interface (ADV). The mean errors of automatic contours compared to manually segmented contours were 1.40%, 4.34% and 6.97%, respectively. The single-layer mean plaque stress value from lumen was 117.91 kPa, 10.79% lower than that from three-layer models (132.33 kPa). On the adventitia, the single-layer mean plaque stress value was 50.46 kPa, 156.28% higher than that from three-layer models (19.74 kPa). The proposed segmentation technique may have wide applications in vulnerable plaque research.

A 7-week rearing trial was designed to investigate the effects of Eucommia ulmoides leaf extract (ELE) on growth performance, body composition, antioxidant capacity, immune response, and disease susceptibility of diet-fed GIFT. The results showed that dietary ELE did not affect growth performance or whole-body composition (p > 0.05). Compared with the control group, plasma ALB contents increased in the 0.06% dietary ELE group (p < 0.05), and plasma ALT and AST activities decreased in the 0.08% dietary ELE group (p < 0.05). In terms of antioxidants, compared with GIFT fed the control diet, 0.06% dietary ELE upregulated the mRNA expression levels of Nrf2 pathway-related antioxidant genes, including CAT and SOD (p < 0.05), and 0.06% and 0.08% dietary ELE upregulated the mRNA levels of Hsp70 (p < 0.05). In terms of immunity, 0.06% dietary ELE suppressed intestinal TLR2, MyD88, and NF-κB mRNA levels (p < 0.05). Moreover, the mRNA levels of the anti-inflammatory cytokines TGF-β and IL-10 were upregulated by supplementation with 0.04% and 0.06% dietary ELE (p < 0.05). In terms of apoptosis, 0.06% and 0.08% ELE significantly downregulated the expression levels of FADD mRNA (p < 0.05). Finally, the challenge experiment with S. agalactiae showed that 0.06% dietary ELE could inhibit bacterial infection, and significantly improve the survival rate of GIFT (p < 0.05). This study demonstrated that the supplementation of 0.04–0.06% ELE in diet could promote intestinal antioxidant capacity, enhance the immune response and ultimately improve the disease resistance of GIFT against Streptococcus agalactiae.

Artificial intelligence (AI) adopting deep learning technology has been widely used in the med-ical imaging domain in recent years. It realized the automatic judgment of benign and malig-nant solitary pulmonary nodules (SPNs) and even replaced the work of doctors to some extent. However, misdiagnoses can occur in certain cases. Only by determining the causes can AI play a larger role. A total of 21 Coronavirus disease 2019 (COVID-19) patients were diagnosed with SPN by CT imaging. Their Clinical data, including general condition, imaging features, AI re-ports, and outcomes were included in this retrospective study. Although they were confirmed COVID-19 by testing reverse transcription-polymerase chain reaction (RT-PCR) with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), their CT imaging data were misjudged by AI to be high-risk nodules for lung cancer. Imaging characteristics included burr sign (76.2%), lobulated sign (61.9%), pleural indentation (42.9%), smooth edges (23.8%), and cavity (14.3%). The accuracy of AI was different from that of radiologists in judging the nature of be-nign SPNs (p < 0.001, κ = 0.036 < 0.4, means the two diagnosis methods poor fit). COVID-19 patients with SPN might have been misdiagnosed using the AI system, suggesting that the AI system needs to be further optimized, especially in the event of a new disease outbreak.

Aquaculture environments harbor complex bacterial communities that are critical for the growth and health of culture species. Apex predators are frequently added to aquaculture ponds to improve ecosystem stability. However, limited research has explored the effects of apex predators on the composition and function of bacterioplankton communities, as well as the underlying mechanisms of community assembly. Using 16S ribosomal RNA (rRNA) high-throughput sequencing, we investigated bacterioplankton communities of crustacean aquaculture ponds with and without apex predators (mandarin fish, Siniperca chuatsi) throughout the culture process. In addition to investigating differences in bacterioplankton communities, we also explored variations in environmental adaptation, functional redundancy, and community stability. Significant differences were observed in bacterioplankton composition among different cultural stages; there was an increase in Bacteriobota and fermentation-related bacteria, but a decrease in Firmicutes and pathogens in the middle stages of aquaculture. Apex predators increased the abundance of organic matter degradation bacteria and decreased pathogens. Bacterioplankton communities under apex predator disturbances had a wider environmental breadth, indicating broader environmental adaptation. Moreover, functional prediction and network analyses revealed that communities under apex predator disturbances were less functionally redundant and unstable. Based on the null model, stochastic processes drove community assembly during aquaculture, whereas apex predators elevated the contribution of deterministic processes. Greater changes in nitrate in culture ponds caused by apex predator disturbances were decisive in controlling the balance between stochasticity and determinism in community assembly. Our study provided insight into the mechanisms underlying bacterioplankton community assembly in aquaculture systems in response to apex predator disturbances.

The purpose of this work is to investigate the effect of the WC content on the surface characteristics and nanoindentation behaviors of WC/Ni-based composite laser-clad coatings. Four NiCrSiBC coatings with WC wt% of 30%, 40%, 50%, and 60%, respectively, were clad on carbon steel substrates using a laser. The morphologies and phase compositions of four clad coatings were comparatively observed. In addition, the hardness and elastic modulus values of the four coatings were measured and quantitatively calculated. As a result, with the increase in WC, the coating grains were more refined. Meanwhile, cracks and WC particle breakage occurred in the 50–60% WC coatings, whereas this was not found in the 30–40% WC coatings. When the WC content increased from 40% up to 50%, the coating hardness and elastic modulus significantly increased. However, a further increase in WC from 50% to 60% did not result in considerable improvement in coating quality but considerably worsened the coating’s cracking behavior instead. Therefore, for WC/Ni-based composite coatings, a threshold exists for the WC content, and this value was 50% within the experimental scope of this study.

To relate the bainitic microstructures to the mechanical properties of steel, the average dislocation density needs to be determined. Using X-ray diffraction and diffraction line broadening analysis, this research quantifies the average dislocation density in the four bainite phase matrices, (upper bainite, upper and lower bainite mixture, lower bainite, lower bainite and martensite mixture), which are transformed in a wide range of isothermal temperatures. The effects of isothermal temperatures on the average dislocation density are assessed for different thermal dynamic driving forces in terms of activation energy and cooling rate. It is found that as isothermal holding temperature is increased, the dislocation density in the bainite matrix decreases from 1.55 × 1017 to 8.33 × 1015 (m−2) due to the reduction in the plastic deformation in the austenite in the transformation. At the same time, the activation energy required decreases only after passing the martensite and lower bainite mixed phase. A new method for better estimating the average dislocation density in bainitic steel is also proposed.

Shanghai has gained much attention in terms of air quality research owing to its importance to economic capital and its huge population. This study utilizes ground-based remote sensing instrument observations, namely by Multiple AXis Differential Optical Absorption Spectroscopy (MAX-DOAS), and in situ measurements from the national air quality monitoring platform for various atmospheric trace gases including Nitrogen dioxide (NO2), Sulfur dioxide (SO2), Ozone (O3), Formaldehyde (HCHO), and Particulate Matter (PM; PM10: diameter ≤ 10 µm, and PM2.5: diameter ≤ 2.5 µm) over Shanghai from June 2020 to May 2021. The results depict definite diurnal patterns and strong seasonality in HCHO, NO2, and SO2 concentrations with maximum concentrations during winter for NO2 and SO2 and in summer for HCHO. The impact of meteorology and biogenic emissions on pollutant concentrations was also studied. HCHO emissions are positively correlated with temperature, relative humidity, and the enhanced vegetation index (EVI), while both NO2 and SO2 depicted a negative correlation to all these parameters. The results from diurnal to seasonal cycles consistently suggest the mainly anthropogenic origin of NO2 and SO2, while the secondary formation from the photo-oxidation of volatile organic compounds (VOCs) and substantial contribution of biogenic emissions for HCHO. Further, the sensitivity of O3 formation to its precursor species (NOx and VOCs) was also determined by employing HCHO and NO2 as tracers. The sensitivity analysis depicted that O3 formation in Shanghai is predominantly VOC-limited except for summer, where a significant percentage of O3 formation lies in the transition regime. It is worth mentioning that seasonal variation of O3 is also categorized by maxima in summer. The interdependence of criteria pollutants (O3, SO2, NO2, and PM) was studied by employing the Pearson’s correlation coefficient, and the results suggested complex interdependence among the pollutant species in different seasons. Lastly, potential source contribution function (PSCF) analysis was performed to have an understanding of the contribution of different source areas towards atmospheric pollution. PSCF analysis indicated a strong contribution of local sources on Shanghai’s air quality compared to regional sources. This study will help policymakers and stakeholders understand the complex interactions among the atmospheric pollutants and provide a baseline for designing effective control strategies to combat air pollution in Shanghai.

The present study investigates the effects of dietary protein levels on glucolipid metabolism, immune function, and resistance to Streptococcus agalactiae of genetically improved farmed tilapia (GIFT) exposed to high temperature. Six practical diets were prepared to feed 360 fish (initial weight 43.78 ± 0.12 g) with graded protein levels (26.45%, 29.28%, 31.69%, 33.68%, 36.18%, and 38.75% dry matter). The results showed that 26.45% dietary protein significantly improved glycolysis by increasing PK mRNA levels, while the 29.28% and 31.69% dietary protein levels promoted gluconeogenesis by increasing PEPCK and G6Pase mRNA levels. For lipid metabolism, 26.45% dietary protein enhanced lipid synthesis by increasing PPAR-γ, SREBP1c, and FAS mRNA levels, while 31.69% dietary protein enhanced the level of lipolysis by increasing the PPAR-α and CPT1 mRNA levels. The highest plasma TG and TC contents were observed in the 29.28% and 31.69% dietary protein groups, respectively. In terms of antioxidants and immunity, the 31.69% dietary protein level activated the expression levels of HSP90 mRNA, thus increasing the expression levels of antioxidant-related genes (CAT, SOD, and GPx), and upregulating the anti-inflammatory factor IL-10 mRNA levels. In addition, regarding the antioxidant enzymes, the highest GSH content was found in the 29.28% dietary protein group, while the 31.69% dietary protein group had the maximum GSH-Px activity. The lowest plasma ALT and AST activities were observed in the 31.69% dietary protein group. Ultimately, the survival rate of juvenile GIFT fed 31.69% dietary protein was highest after a Streptococcus agalactiae challenge. Overall, 29.28–31.69% dietary protein was recommended in the diet of GIFT in a high-temperature environment.

Stocking density has been identified as one of the main factors affecting fish growth, welfare and behavior. However, few studies have focused on the effects of stocking density on fish health in integrated rice–fish farming systems. Thus, the aim of this study was to evaluate the effects of different stocking densities on the growth performance, physiological parameters, redox status and lipid metabolism of Micropterus salmoides in an integrated rice–fish farming system. The fish were reared at three densities: low density (LD, 40 g/m3), medium density (MD, 80 g/m3) and high density (HD, 120 g/m3) for 90 days. At the end of the experiment, fish reared in the MD and HD groups showed lower growth performance than those from the LD group. The HD treatment significantly altered the physiological parameters, including glucose and lactate. Meanwhile, the HD treatment induced oxidative stress and lipid peroxidation after 90 days of farming. Furthermore, transcriptomic analysis revealed that HD treatment led to abnormal lipid metabolism. Interestingly, we found the suppression of three key pathways related to lipid metabolism, including the PPAR, insulin and adipocytokine signaling pathways, in the HD group. Overall, our data indicated that the HD treatment inhibited growth and caused physiological responses, oxidative stress and abnormal hepatic lipid metabolism in M. salmoides in an integrated rice–fish farming system.

The wafer-scale fabrication of two-dimensional (2D) semiconductor thin films is the key to the preparation of large-area electronic devices. Although chemical vapor deposition (CVD) solves this problem to a certain extent, complex processes are required to realize the transfer of thin films from the growth substrate to the device substrate, not to mention its harsh reaction conditions. The solution-based synthesis and assembly of 2D semiconductors could realize the large-scale preparation of 2D semiconductor thin films economically. In this work, indium selenide (In2Se3) nanosheets with uniform sizes and thicknesses were prepared by the electrochemical intercalation of quaternary ammonium ions into bulk crystals. Layer-by-layer (LbL) assembly was used to fabricate scalable and uniform In2Se3 thin films by coordinating In2Se3 with poly(diallyldimethylammonium chloride) (PDDA). Field-effect transistors (FETs) made from a single In2Se3 flake and In2Se3 thin films showed mobilities of 12.8 cm2·V−1·s−1 and 0.4 cm2·V−1·s−1, respectively, and on/off ratios of >103. The solution self-assembled In2Se3 thin films enriches the research on wafer-scale 2D semiconductor thin films for electronics and optoelectronics and has broad prospects in high-performance and large-area flexible electronics.

In aquaculture, constructed wetland (CW) has recently attracted attention for use in effluent purification due to its low running costs, high efficiency and convenient operation,. However, less data are available regarding the long-term efficiency of farm-scale CW for cleaning effluents from inland freshwater fish farms. This study investigated the effectiveness of CW for the removal of nutrients, organic matter, phytoplankton, heavy metals and microbial contaminants in effluents from a blunt snout bream (Megalobrama amblycephala) farm during 2013–2018. In the study, we built a farm-scale vertical subsurface flow CW which connected with a fish pond, and its performance was evaluated during the later stage of fish farming. The results show that CW improved the water quality of the fish culture substantially. This system was effective in the removal of nutrients, with a removal rate of 21.43–47.19% for total phosphorus (TP), 17.66–53.54% for total nitrogen (TN), 32.85–53.36% for NH4+-N, 33.01–53.28% NH3-N, 30.32–56.01% for NO3−-N and 42.75–63.85% for NO2−-N. Meanwhile, the chlorophyll a (Chla) concentration was significantly reduced when the farming water flowed through the CW, with a 49.69–62.01% reduction during 2013–2018. However, the CW system only had a modest effect on the chemical oxygen demand (COD) in the aquaculture effluents. Furthermore, concentrations of copper (Cu) and lead (Pb) were reduced by 39.85% and 55.91%, respectively. A microbial contaminants test showed that the counts of total coliform (TC) and fecal coliform (FC) were reduced by 55.93% and 48.35%, respectively. In addition, the fish in the CW-connected pond showed better growth performance than those in the control pond. These results indicate that CW can effectively reduce the loads of nutrients, phytoplankton, metals, and microbial contaminants in effluents, and improve the water quality of fish ponds. Therefore, the application of CW in intensive fish culture systems may provide an advantageous alternative for achieving environmental sustainability.

An indoor high and open space is characterized by high mobility of people and uneven temperature distribution, so the conventional design and operation of air conditioning systems makes it difficult to regulate the air conditioning system precisely and efficiently. Thus, a Wireless Sensor Network was constructed in an indoor space located in Hong Kong to monitor the indoor environmental parameters of the space and improve the temperature control effectively. To ensure the continuity of the measurement data, three algorithms for reconstructing temperature, relative humidity and carbon dioxide data were implemented and compared. The results demonstrate the accuracy of support vector regression model and multiple linear regression model is higher than Back Propagation neural network model for reconstructing temperature data. Multiple linear regression is the most convenient from the perspective of program complexity, computing speed and difficulty in obtaining input conditions. Based on the data we collected, the traditional single-input-single-output control, zonal temperature control and the proposed zonal demand control methods were modeled on a Transient System Simulation Program (TRNSYS) control platform, the thermal coupling between the subzones without physical partition was taken into account, and the mass transfer between the virtual boundaries was calculated by an external CONTAM program. The simulation results showed the proposed zonal demand control can alleviate the over-cooling or over-heating phenomenon in conventional temperature control, thermal comfort and energy reduction is enhanced as well.

In this paper, several multi-layer-coupled star-composed networks with similar symmetrical structures are defined by using the theory of graph operation. The supra-Laplacian matrix of the corresponding multi-layer networks is obtained according to the master stability equation (MSF). Two important indexes that reflect the synchronizability of these kinds of networks are derived in the case of bounded and unbounded synchronized regions. The relationships among the synchronizability, the number of layers, the length of the paths, the branchings, and the interlayer and intralayer coupling strengths in the two cases are studied. At the same time, the simulation experiments are carried out with the MATLAB software, and the simulated images of the two symmetrical structure networks’ synchronizability are compared. Finally, the factors affecting the synchronizability of multi-layer-coupled star-composed networks are found. On this basis, optimization schemes are given to improve the synchronizability of multi-layer-coupled star-composed networks and the influences of the number of central nodes on the networks’ synchronizability are further studied.