Climate change is altering the Earth's water cycle system. The resulting three extreme weather events—heatwaves, droughts, and extreme precipitation—impacts urban and rural water security through multi-layered mechanisms. A primary structural disparity exists between urban and rural systems: while urban areas benefit from comprehensive and standardized pipe networks that ensure terminal water quality, rural areas often suffer from "last mile" vulnerability due to inadequate infrastructure and outdated purification facilities. Extreme weather can directly alter the microbial community structure, concentrations of chemical pollutants and physicochemical properties of source water. These alterations interfere with the efficiency of water treatment processes and ultimately compromise the integrity of distribution systems. Because distribution networks often lack real-time monitoring and adaptive response capabilities, they have emerged as the most vulnerable link in the "water source-water treatment-distribution system" chain. Based on a systematic analysis of these chain-wide impacts, this paper proposed a series of control strategies, including security frameworks based on multi-model coupling and water source protection measures, improvement of water treatment technologies, optimization of distribution systems, and development of new water quality monitoring methods. These strategies aim to enhance the climate adaptability of urban and rural drinking water systems through multi-dimensional intervention, providing a theoretical basis for constructing climate-resilient water infrastructure.

Objective: To explore the association between negative life events and smartphone addiction among middle school students, so as to provide theoretical support and practical guidance for prevention and intervention of smartphone addiction among middle school students. Methods: Using cluster sampling, 8 890 students were selected to survey from 27 junior high schools and 3 senior high schools in a district of Shenzhen in 2022 (baseline) and 2023 (followup). Data were collected through selfresigned questionnaires on basic information, the Smartphone Addiction Scale-Short Version, and the Adolescent Selfrating Life Events Checklist. Mixedeffects models were employed to analyze the association. Results: Compared to 2022, the punishment scores of middle school students in 2023 [1.00 (0.00, 6.00) and 1.00 (0.00, 6.00)] decreased (Z=4.27), while the scores of interpersonal stress, learning stress and adaptation [4.00(0.00, 8.00), 4.00(0.00, 8.00); 4.00(1.00, 8.00), 5.00(2.00, 9.00); 2.00 (0.00, 6.00), 3.00 (0.00, 7.00)] increased (Z=-3.04, -8.36, -6.80) (P<0.01). Mixedeffects models revealed a positive doseresponse relationship between negative life events and smartphone addiction (OR=1.08-1.17, P<0.01). Stepwise regression showed independent positive effects of interpersonal stress (OR=1.05), academic stress (OR=1.03), and adaptation stress (OR=1.11) on smartphone addiction (P<0.01). Subgroup analysis of nonaddicted students in 2022 confirmed persistent associations for academic stress (OR=1.03) and adaptation (OR=1.07) (P<0.01). Conclusion Negative life events exhibit a positive doseresponse relationship with smartphone addiction, particularly interpersonal stress, academic stress, and adaptationrelated events.

Objective: To explore the potential causal association between adolescent compulsive behaviour and smartphone addiction based on longitudinal data, so as to provide reference for the establishment of adolescent smartphone addiction interventions. Methods: A preliminary survey and follow-up were conducted on 8 907 middle and high school students in a district of Shenzhen in 2022 and 2023, respectively. Compulsive behaviours were measured by using the Mental Health Inventory for Middle School Students-60 Items (MMHI-60), smartphone addiction was assessed by using the Smartphone Addiction Scale-Short Version ( SAS- SV), and the associations between compulsive behaviours and smartphone addiction were analysed by using multilevel mixed-effects models and subgroup analyses. Results: Smartphone addiction detection rates among middle school students were significantly associated with genders, father s education level, mother s education level, study load subgroups, and whether or not they were single-parent families, and there were statistical differences ( χ 2=17.21-175.34, P <0.05). Students with compulsive behaviours were 2.98 times more likely to develop smartphone addiction than those without compulsive behaviours ( OR=2.98, 95%CI=2.77-3.22, P <0.05). Subgroup analysis of middle school students without smartphone addiction in the first year found that compulsive behaviours significantly predicted smartphone addiction ( OR= 1.76 , 95%CI=1.54-2.01, P <0.05). Conclusion There is a potential causal association between obsessive-compulsive behaviours and smartphone addiction in middle school students, and obsessive-compulsive behaviours in middle school students could significantly predicted the occurrence of smartphone addiction.

Objective:To investigate the epidemiological trends of viral diarrhea pathogens in children in Baotou city, and to provide reference for controlling the prevalence of viral diarrhea and guiding the development of regional vaccines.Methods:Fecal samples were collected from children under five years old hospitalized with viral diarrhea at two sentinel hospitals in Baotou from June 2023 to May 2024. Real-time PCR was used to detect group A rotavirus, norovirus, adenovirus, and astrovirus. Statistical analysis was performed using SPSS 20.0 software, with Chi-square tests conducted to assess differences. A P value<0.05 was considered statistically significant. Results:A total of 246 fecal samples were collected, including 153 from males and 93 from females. Among these, 135 samples tested positive, yielding a positivity rate of 54.88% (135/246). There were 82 positive samples from male children and 53 from female children, with no significant difference between genders. Most positive samples (51.85%, 70/135) tested positive for two viruses. Specifically, co-infections of group A rotavirus with norovirus or adenovirus accounted for 98.57% (69/70) of all co-infected cases. Significant differences in detection rates were observed across age groups (χ 2=29.803, P<0.001), with the highest positivity rates in children under one year old and in the 1-year age group. Seasonality, viral diarrhea in Baotou was more prevalent in winter and spring. The G8P[8] genotype of group A rotavirus was the predominant strain. Conclusions:From June 2023 to May 2024, viral diarrhea in hospitalized children under five years old in Baotou is primarily caused by co-infections of group A rotavirus and norovirus, with a higher incidence in preschool-aged children. The G8P[8] genotype of group A rotavirus is the dominant strain. It is recommended to strengthen vaccination and surveillance efforts for viral diarrhea in preschool children, particularly during the winter and spring seasons.

Objective:To analyze the epidemiological characteristics of influenza-like illness（ILI）and the genetic evolutionary trends of the hemagglutinin（HA）and neuraminidase（NA）genes of influenza A（H3N2）viruses isolated in Baotou during the 2022-2023 influenza season.Methods:Etiological surveillance data for ILI cases in Baotou during the 2022-2023 influenza season were collected from the China Influenza Surveillance Information System. Descriptive statistical analysis was performed on the data. HA and NA genes of 30 influenza A（H3N2）viruses were sequenced. Amino acid variation sites，glycosylation sites，drug resistance genes，and phylogenetic trees were analyzed using MEGA 11 software and the NextClade online analysis tool.Results:A total of 1 443 ILI specimens were tested，of which 241（16.70%）were positive for influenza viruses. Among the positive cases，influenza A（H3N2）virus-positive cases accounted for 75.93%（183/241）. The nucleotide sequence similarity of the HA gene between the 30 influenza A（H3N2）isolates and the vaccine strains A/Hong Kong/2671/2019（H3N2），A/Cambodia/e0826260/2020（H3N2），and A/Darwin/9/2021（H3N2）ranged from 96.83% to 98.77%，while the amino acid sequence similarity ranged from 94.63% to 99.62%. A total of 14 amino acid variation sites and 11 conserved glycosylation sites were identified in the HA gene. For the NA gene，the nucleotide sequence similarity ranged from 98.37% to 99.65%，and the amino acid sequence similarity ranged from 94.64% to 98.28%. A total of three amino acid variation sites and nine conserved glycosylation sites were found in the NA gene. None of the 30 influenza A（H3N2）isolates had mutations associated with drug resistance，and all belonged to the clade 3C.2a1b.2a.2a.3a.1.Conclusions:During the 2022-2023 influenza season in Baotou，the circulating influenza A（H3N2）viruses belong to the same evolutionary clade as the 2021-2022 vaccine strain A/Cambodia/e0826360/2020（H3N2）. The isolates from different sources share a common evolutionary origin；however，variations are observed across the genome in terms of homology，molecular mutations，and glycosylation patterns.

Objective:To investigate the status of allostatic load (AL) in patients with polycystic ovary syndrome (PCOS) and its influence on the clinical outcomes of in vitro fertilization-embryo transfer.Methods:This was a prospective study. By using convenient sampling method, 421 patients with PCOS (PCOS group) and 372 control infertility patients (control group) in the Reproductive Center of the First Affiliated Hospital of Anhui Medical University from April 2022 to January 2024 were investigated for basic information, physical examination, laboratory examination and follow-up of clinical outcomes. The total score of AL was calculated using 16 related indicators of cardiovascular system, metabolic system and immune system, and AL>3 was used as the judgment criteria for the high level AL group and the low level AL group. The differences in general data, embryo development and clinical outcomes between the groups were compared.Results:There were 222 cases (52.7%, 222/421) in PCOS low level AL group and 199 cases (47.3%, 199/421) in PCOS high level AL group. There were 214 patients (57.5%, 214/372) in the control low level AL group and 158 patients (42.5%, 158/372) in the control high level AL group. Embryo development outcomes: number of oocytes retrieved (median: 12, 12, 19, 14, respectively; P<0.001), number of two pronuclei (median: 8, 7, 11, 8, respectively; P<0.001), number of fertilization (median: 9, 9, 13, 10, respectively; P<0.001), number of metaphase of meiosis Ⅱ oocytes (median: 9, 8, 13, 10, respectively; P<0.001), number of transferable embryos (median: 5, 5, 7, 6, respectively; P<0.001), number of high-quality embryos (median: 4, 3, 6, 5, respectively; P<0.001), gonadotropin(Gn) starting dosage (median: 150, 200, 150, 200 U, respectively; P<0.001), total dosage of Gn (median: 1 800, 2 075, 1 575, 2 025 U, respectively; P<0.001), duration of Gn used (median: 10, 10, 10, 10 days, respectively; P=0.027) in the control low level AL group, control high level AL group, PCOS low level AL group and PCOS high level AL group were significantly different. Pairings between groups showed that number of oocytes retrieved, number of two pronuclei, number of fertilization, number of metaphase of meiosis Ⅱ oocytes and number of transferable embryos in PCOS high level AL group were lower than those in PCOS low level AL group (all P<0.05); Gn starting dosage and total dosage of Gn in PCOS low level AL group were lower than those in the other three groups (all P<0.05); duration of Gn used in PCOS high level AL group was higher than that PCOS low level AL group ( P<0.05). Clinical outcomes: the control low level AL group, control high level AL group, PCOS low level AL group and PCOS high level AL group underwent fresh transplantation [27.4% (57/208), 24.4% (38/156), 15.1% (32/212), 17.1% (33/193), respectively; P=0.006] and the proportion of transplanted day 5 embryos [82.7% (172/208), 77.6% (121/156), 91.0% (193/212), 86.5% (167/193), respectively; P=0.018] were statistically significant. There were no significant differences in fertilization rate, biochemical pregnancy rate, clinical pregnancy rate, multiple pregnancy rate and early abortion rate among the four groups (all P>0.05). Conclusion:The high level of AL in PCOS patients may affect the outcomes of embryo development, and more attention should be paid to AL in PCOS patients to reduce stress.

With population aging worldwide,Alzheimer's disease(AD)has become a serious human health issue.Owing in part to the complexity of the pathogenesis of AD,effective therapeutic options are lacking.Mesenchymal stem cell-derived exosomes(MSC-Exos)have powerful regenerative properties and repair functions,providing a new direction for treatment.They are donor-derived,easily stored,natural carriers,with low immunogenicity and a low risk of tumor formation.They have shown great potential in the treatment of AD and post-treatment rehabilitation.This article introduces the pathological mechanisms of AD and characteristics of MSC-Exos,provides a detailed review of the roles of MSC-Exos in the treatment of AD,including anti-inflammatory effects,immunomodulatory effects,and related signaling pathway modulation,and summarizes recent research progress,with the aim of providing a basis for the development of novel therapeutic approaches to AD.

Morphometric similarity gradient;White matter hyperintensity;Connectivity gradient Objective To investigate the change in morphometric similarity gradient in patients with white matter hyperintensity （WMH）-related cognitive impairment and its influence on cognitive function. Methods Baseline and neuroimaging data were collected from 141 healthy controls （HC group）， 66 patients with WMH and normal cognition （WMH-NC group）， and 134 patients with WMH and cognitive impairment （WMH-CI group）. The difference in gradient was compared between groups based on the morphometric similarity gradient analysis. The mediating effect model was used to investigate the association between WMH volume，plasma biomarkers for nerve injury， gradient， and cognitive function. Results The research findings showed significant aberrant alternations in morphometric similarity gradient， with a significant increase in variability in the second gradient （P=0.036， not surviving FDR correction）. There was a significant negative correlation between the second gradient and geodesic distance （Pspin<0.001）. In addition，visual cortex gradient played a key mediating role in the association between p-tau181/WMH volume and visuospatial function. Conclusion Patients with WMH-related cognitive impairment have aberrant macroscopic connectivity patterns of the cortex. The aberrant pattern of regional cortex mediates the process in which p-tau181 and WMH volume affect cognitive function， which provides a new perspective for understanding the potential structural mechanism of WMH-related cognitive impairment.

Objective : To predict and validate key targets for cisplatin(DDP) resistance in colorectal cancer(CRC) to provide more options for precision medicine in clinical treatment. Methods: Differentially expressed genes(DEGs) between normal colonic mucosa and CRC were screened from the gene expression omnibus(GEO) database. Key genes were identified using the STRING database and Cytoscape software. DEGs were subjected to enrichment analysis using the gene ontology(GO) and kyoto encyclopedia of genes and genomes(KEGG) databases. Key targets were validated through RNA-seq, qRT-PCR, and Western blot. The versican(VCAN) gene overexpression vector was transfected into human ileocecal colorectal adenocarcinoma cell line HCT8, and cell viability was assessed using the CCK-8 assay. Flow cytometry was used to assess apoptosis and cell cycle distribution. qRT-PCR and Western blot were performed to detect mRNA and protein levels of the target genes. Results : In this study, 118 upregulated DEGs and 146 downregulated DEGs were identified from the GEO database. DEGs were mainly enriched in extracellular matrix degradation, extracellular matrix organization, and the phosphoinositide 3-kinase(PI3K)-protein kinase B(AKT) signaling pathway. Based on protein-protein interaction network analysis, 20 hub genes were identified. By comparing the transcriptome sequencing results of the HCT8 parental strain and DDP-resistant strain, the VCAN gene was further selected. In CRC tissues, the expression level of VCAN was higher than that in normal colonic mucosa, and patients with high VCAN expression had shorter overall survival(OS) and recurrence free survival(RFS) times. Overexpression of VCAN in CRC cells promoted cell proliferation(P<0.05), increased resistance to DDP, reduced DDP-induced apoptosis(P<0.05), and G0/G1phase arrest(P<0.05); upregulation of VCAN activated the protein kinase B(AKT)-mammalian target of rapamycin(mTOR) signaling pathway. Conclusion Bioinformatics and transcriptome sequencing identified VCAN as a key target gene for DDP resistance in CRC, potentially promoting CRC progression and DDP resistance by regulating the AKT-mTOR pathway.

Objective To explore the mechanism of action of Huaier (Vanderbylia robiniophila) against pancreatic cancer. Methods The chemical components and targets of Huaier (Vanderbylia robiniophila) were searched through the Herb database. Pancreatic cancer-related targets were screened from GeneCards, NCBI, and DisGeNET online databases, and a Venn diagram was drawn to obtain the intersection targets of drugs and diseases. The protein-protein interaction (PPI) network was constructed using the String platform, and a series of network diagrams were drawn using Cytoscape 3.8.0 software to screen core targets and perform GO analysis and KEGG pathway enrichment analysis on the target genes. Finally, the key active components were molecularly docked with potential target genes using AutoDock software. The KEGG enrichment top 20 pathways and the whole-genome association analysis data of pancreatic cancer were used to further validate the results using the Open GWAS database through Mendelian randomization analysis. Results A total of 4 effective components of Huaier (Vanderbylia robiniophila) were identified, 112 drug-disease intersection targets, the main active components were kaempferol, rutin, genistein, and glucuronic acid, and the core targets were mitogen-activated protein kinase 8 (MAPK8), uridine diphosphate(UDP)-glucuronic acid transferase 1 family peptide A1 (UGT1A1), and superoxide dismutase 2 (SOD2). The mechanism of action may be related to pancreatic cancer, tumor necrosis factor(TNF) signaling pathway, and interleukin(IL)-17 signaling pathway. The molecular docking showed that the main active components had good docking activity with the key targets. After screening, 73 genes were retained, and 24,195,229 single nucleotide polymorphism(SNP) were used for two-sample Mendelian randomization analysis. The analysis results showed that MAPK8 may be an important therapeutic target for pancreatic cancer. Conclusions Huaier (Vanderbylia robiniophila) may exert an anti-pancreatic cancer effect by acting on MAPK8, providing initial theoretical evidence for further verifying the mechanism of action of Huaier in treating pancreatic cancer.