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terminal water quality, rural areas often suffer from "last mile" vulnerability due to inadequate infrastructure and outdated purification facilities.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 assess the effectiveness of kinetic parameters of 18F-prostate specific membrane antigen (PSMA)-1007 PET/MR in distinguishing tumor recurrence (TR) from radiation necrosis (RN) in glioma patients. Methods:From January 2023 to June 2023, imaging data of 10 patients (6 males, 4 females; media age of 39.5 years) with gliomas who were suspected of recurrence and were referred for 18F-PSMA-1007 PET/MR scans at Sun Yat-Sen University Cancer Center were retrospectively analyzed. Static parameters from 18F-PSMA-1007 PET scans, including SUV max, SUV mean, metabolic tumor volume (MTV), and total lesion′s PSMA (TLP), as well as dynamic parameters including K 1, k 2, k 3, k 4, net influx rate (K i), and volume of distribution ( Vt) were obtained by using compartmental and multigraphical models. Additionally, parameters from dynamic contrast-enhanced MRI (DCE-MRI) were collected. Mann-Whitney U test was used to compare parameter differences between TR and RN groups. Spearman rank correlation analysis was used to explore the correlation between K i and DCE-MRI parameters. Results:Finally, 8 cases were diagnosed as TR and 2 cases were diagnosed as RN. The kinetic compartmental model-based evaluation determined that irreversible 2-tissue model (2T3K) provided the best-fitting results. The differences in SUV mean (median: 2.48 vs 0.89; Z=-2.09, P=0.044), SUV max (median: 4.04 vs 1.40; Z=-2.09, P=0.044), and K i (median: 1.33×10 -2vs 3.87×10 -3;Z=-2.10, P=0.044) between TR and RN groups were statistically significant. Some parameters of DCE-MRI also showed differences between the two groups ( Z=-2.09, P=0.044 for all). The K i yielded moderate correlation with DCE-MRI parameter Ve ( rs=0.650, P=0.042), while correlations between K i and other DCE-MRI parameters were not significant ( rs values: from -0.207 to 0.632, all P>0.05). Conclusion:Dynamic and multi-parametric 18F-PSMA-1007 PET/MR system holds promise for accurately distinguishing TR from RN in treated glioma patients.

Objective:To assess the effectiveness of kinetic parameters of 18F-prostate specific membrane antigen (PSMA)-1007 PET/MR in distinguishing tumor recurrence (TR) from radiation necrosis (RN) in glioma patients. Methods:From January 2023 to June 2023, imaging data of 10 patients (6 males, 4 females; media age of 39.5 years) with gliomas who were suspected of recurrence and were referred for 18F-PSMA-1007 PET/MR scans at Sun Yat-Sen University Cancer Center were retrospectively analyzed. Static parameters from 18F-PSMA-1007 PET scans, including SUV max, SUV mean, metabolic tumor volume (MTV), and total lesion′s PSMA (TLP), as well as dynamic parameters including K 1, k 2, k 3, k 4, net influx rate (K i), and volume of distribution ( Vt) were obtained by using compartmental and multigraphical models. Additionally, parameters from dynamic contrast-enhanced MRI (DCE-MRI) were collected. Mann-Whitney U test was used to compare parameter differences between TR and RN groups. Spearman rank correlation analysis was used to explore the correlation between K i and DCE-MRI parameters. Results:Finally, 8 cases were diagnosed as TR and 2 cases were diagnosed as RN. The kinetic compartmental model-based evaluation determined that irreversible 2-tissue model (2T3K) provided the best-fitting results. The differences in SUV mean (median: 2.48 vs 0.89; Z=-2.09, P=0.044), SUV max (median: 4.04 vs 1.40; Z=-2.09, P=0.044), and K i (median: 1.33×10 -2vs 3.87×10 -3;Z=-2.10, P=0.044) between TR and RN groups were statistically significant. Some parameters of DCE-MRI also showed differences between the two groups ( Z=-2.09, P=0.044 for all). The K i yielded moderate correlation with DCE-MRI parameter Ve ( rs=0.650, P=0.042), while correlations between K i and other DCE-MRI parameters were not significant ( rs values: from -0.207 to 0.632, all P>0.05). Conclusion:Dynamic and multi-parametric 18F-PSMA-1007 PET/MR system holds promise for accurately distinguishing TR from RN in treated glioma patients.

Objective:To study the predictive value of serum albumin (ALB) on the first day of life for early-onset sepsis (EOS) in very low birth weight infants (VLBWI).Methods:From January 2015 to December 2020, clinical data of VLBWI (gestational age < 34 weeks, birth weight < 1 500 g) born and hospitalized in our hospital were collected. Based on the serum ALB level at admission, the infants were assigned into high, moderate and low ALB groups. C-reactive protein (CRP) and procalcitonin (PCT) levels among different ALB groups were compared. The infants were also assigned into EOS and non-EOS groups according to the occurrence of EOS and perinatal complications were compared between the two groups. The relationship between EOS and ALB level was analyzed. The predictive value of serum ALB was studied using receiver operating characteristic (ROC) curve analysis.Results:A total of 183 infants were enrolled, including 62 in the high ALB group, 87 in the moderate ALB group and 34 in the low ALB group; and 36 in EOS group and 147 in non-EOS group. The incidence of maternal chorioamnionitis was significantly higher in EOS group than non-EOS group [33.3% (12/36) vs. 6.8% (10/147), P<0.001]. Serum CRP and PCT in the low and moderate ALB groups were significantly higher than the high ALB group ( P<0.05), and the low ALB group showed higher CRP and PCT than the moderate ALB group ( P<0.05). Compared with the non-EOS groups, ALB in the EOS group was significantly lower [24.9 (24.0, 28.5) g/L vs. 29.5 (27.4, 31.2) g/L, P<0.001] and the incidence of hypoproteinemia was significantly higher [52.8% vs.10.2%, P<0.001]. As ALB decreased, the incidence of EOS increased. The incidence of EOS was 55.9% in the low ALB group, 16.1% in the moderate ALB group and 4.8% in the high ALB group ( P<0.001). The sensitivity and specificity of ALB predicting EOS was 69.4% and 79.6%, respectively, with a cut-off value of 27.0 g/L. Conclusions:The VLBWI with maternal chorioamnionitis and serum albumin lower than 27.0 g/L on the first day of life have higher risk of EOS.

Objective:To evaluate the accuracy of glomerular filtration rate (GFR) assessed from the renal dynamic imaging method (Gates method) with 99Tc m-diethylene triamine pentoacetic acid (DTPA) in the heart transplant population. Methods:From September 2017 to June 2018, 34 patients with advanced heart failure who were prepared for surgery (30 males, 4 females; age: (45±14) years; heart transplant group) and 41 patients with normal heart function (19 males, 22 females; age: (50±17) years; control group) in Fuwai Hospital were respectively enrolled. GFRs of all patients were measured using Gates method (gGFR) and dual plasma sample method (DPSM; dGFR) with 99Tc m-DTPA. The accuracy of Gates method for detecting GRF was verified by using DPSM as the reference. Seventeen patients in heart transplant group underwent 99Tc m-DTPA renal dynamic imaging for Gates and DPSM results repeatedly after the surgery. The single kidney (left and right) functions (dGFRL and dGFRR) of DPSM were obtained according to the results of Gates method. Pearson correlation analysis and paired t test were used to analyze the data. Results:The gGFR in heart transplant group was higher than dGFR ((66.49±15.66) vs (49.16±13.24) ml·min -1·1.73 m -2; t=6.728, P<0.01), and there was a moderate correlation between them ( r=0.467, P<0.01). No difference between gGFR and dGFR in control group was observed ((65.35±26.28) vs (62.22±21.37) ml·min -1·1.73 m -2; t=1.268, P=0.212), and there was a good correlation between them ( r=0.799, P<0.01). The difference between 2 correlation coefficients was statistically significant ( z=-2.44, P<0.05). Serum creatinine decreased, while dGFR, dGFRL and dGFRR increased after the surgery, suggesting the improved renal function. Conclusions:The renal dynamic imaging method (Gates method) with 99Tc m-DTPA has less accuracy in the heart transplant patients. Combination of DPSM and Gates method can provide the precise total GFR and assess single kidney GFR, and may serve as a tool to monitor the renal function for the heart transplant patients in clinic.

Objective To observe the metabolic changes of subcortical structures in children with intractable epilepsy using 18 F-FDG PET/CT,and to investigate the mechanism of subcortical structure involvement in epileptic seizures and its clinical significance.Methods Features of 18F-FDG PET/CT imaging in 611 intractable epilepsy children were analyzed.The metabolic changes of cortex and subcortical structures (basal ganglia,thalamus and cerebellum) were observed.The children were divided into three groups (young,middle and older groups) according to age,also mild group and severe group according to the number of involved lobar,respectively.The incidence of metabolic abnormalities in subcortical structures of different groups were analyzed.Results Among 611 children,unilateral cortical metabolic abnormality was found in 525,and bilateral cortical metabolic abnormalities were found in 86 children.The involvement of subcortical structures was detected in 190 children,including basal ganglia (n=64),thalamus (n=113) and cerebellum (n=105).The incidence of metabolic abnormality in subcortical structures under different age groups was not statistically different (all P＞ 0.05),while the incidence of metabolic abnormality in subcortical structures of severe group was significantly higher than that of mild group (all P＜0.001).Conclusion 18 F-FDG PET/CT might be able to detect the metabolic abnormalities of subcortical structures,therefore indicating the involvement of cerebral cortex.

Objective: To characterize the gut microbial community structure of two-kidney-one-clip (2K1C) hypertensive rats, provide new evidences for prevention and treatment of hypertension. Methods: Adult male SD rats were divided into 2K1C hypertensive model group and sham operation group (n=8 each). Blood pressure was recorded by tail-cuff technique weekly for 4 weeks. Then, the total fecal DNA of rats in 2K1C model group and sham operation group were extracted. The structure and principal components of intestinal flora in 2K1C model rats and sham operated rats were analyzed using Hiseq3000 sequencing platform. Additionally, real time fluorescent quantitative polymerase chain reaction technology was used to detect the content of predominant bacteria, including Escherichia, Bifidobacterium, Lactobacillus and Bacteroides. Results: Compared with sham operation group, significant reduction in the relative abundance of Firmicutes (31.72 (30.06, 32.18) vs. 40.99 (38.78, 44.41), U=0.00, P<0.05) and increase in Bacteroidetes (48.13(41.16,50.25) vs. 27.81(25.84,31.38),U=0.00, P<0.05) were observed in the fecal samples from model group. The relative abundance of Escherichia coli (0.08(0.07,0.11) vs. 0.07(0.06,0.08),U=12.50, P<0.05) was increased and the short chain fatty acid producing strains such as Coprococcus, Roseburia, Blautia, Clostridium and Bacteroides was reduced in 2K1C model group than in sham operation group (all P<0.05). Moreover, the relative abundance of Prevotella (Bacteroidetes) was also significantly higher in 2K1C model group than in sham operation group (18.14(17.78,18.75) vs.1.83(1.50,5.19), U=0.00, P<0.05). Moreover, the relative abundance of Ruminococcus (Firmicutes) was significant higher in 2K1C model group than in sham operation group (7.73(6.04,9.34) vs. 3.68(2.46,4.67),U=0.00, P<0.05). Principal coordinate analysis showed that there was significant difference in the gut microbial community structure between 2K1C model group and sham operation group. Conclusion There are significant changes in the gut microbial community structure in 2K1C model group as compared to sham operation group, indicating renovascular hypertension might affect gut microbial community structure in this rat model.

Purpose To explore the value of spectral coronary CT angiography (CCTA) in reducing radiation dose and contrast dose using individualized optimal monochromatic imaging.Materials and Methods Sixty patients with suspected coronary disease were recruited in the study,who were randomly divided into two groups:group A (n=30) using conventional CT protocol with 350 mgI/ml contrast agent;group B (n=30) using low dose spectral CT imaging mode with 300 mgI/ml contrast agent.The images of group A were reconstructed with conventional process,and the images of group B were reconstructed with Optimal CNR to obtain the optimal monochromatic energy images.The images of both groups were transferred to an Advanced Workstation for analysis.Double-blinded method was carried out to qualify the images.CT values of coronary artery segments,as well as standard deviations (SD),the signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR) of aortic sinus were measured.Radiation doses and iodine intake were compared between the two groups.The optimal keV distribution in group B was analyzed.Results There was no significant difference for the subjective scoring of image quality,CT value of each coronary artery segment,SD,SNR,and CNR values between the two groups (P＞0.05).The effective radiation dose and total iodine load in group B were less than that in group A (P＜0.05).The optimal energy distribution for group B was 60-75 keV,average at (66.50+3.91) keV.Conclusion Compared with the conventional CT protocol,spectral CT imaging at optimal energy levels combined with iterative reconstruction can effectively reduce the radiation dose and iodine load,and obtain better images than usual protocol.

Objective To explore the application of low dose of radiation combined with low concentration of contrast medium in the energy spectrum CT of the coronary artery angiography.Methods 60 patients with suspected diagnosis of coronary heart disease were randomly divided into A,B two groups,30 cases in each group.Group A with 350 mg I/mL contrast agent,undergoing conventional CT scanning;Group B using 300 mg I/mL contrast agent,the gems energy spectrum CT scanning with low-dose.Two groups both adopted forward-looking heart switch control scanning mode.After scanning,group A reconstructed conventional images of 40% ASiR sequence,group B rebuilded axial surface images of single energy 65 keV and 40% ASiR sequence,all the reconstruction images were introduced to AW4.6 workstations used for analysis.Double-blind subjective rating was done by two experienced doctors to measure CT values and SD of aortic sinus (AS),left main (LMA),the left anterior descending branch proximal (LAD-p),left circumflex branch proximal (LCX-p), right coronary artery proximal (RCA-p)and pericardial fat,AS the noise (SD),to calculate the signal-to-noise ratio (SNR)and contrast to noise ratio (CNR),to calculate the effective doses of radiation(ED)by recording CTDI and DLP,and to record iodine intake.By using two independent samples t test to compare two groups of patients’the effective radiation doses,iodine intake,the average CT value,SD,SNR and CNR.Results The subjective image quality score differences and coronary measuring section CT values between the two groups had no statistical significance.In the aspects of effective radiation dose,group B reduced about 29% compared to group A,the difference was statistically significant.Iodine intake in group B decreased about 16% than in group A.Conclusion In coronary artery CT imaging, spectral scanning with low dose of radiation and reconstruction images with single energy can effectively reduce the radiation dose and iodine intake,at the same time it can obtain the approximate image quality like conventional scanning.

PurposeTo explore the feasibility of personalized energy spectrum scanning in upper abdomen CT by comparing the image quality and radiation dose of optimizing choice spectrum scanning protocol with conventional 120 kVp scan.Material and Methods Sixty patients undergoing abdominal CT scan with and without contrast enhancement were prospectively collected and randomly assigned into two groups. Group A (30 patients) underwent conventional 120 kVp scan and spectral enhancement scanning; group B (30 patients) underwent spectrum scan and 120 kVp enhancement scanning. Spectral scanning protocol was based on individual choice with conventional 120 kVp NI10-5 mm average mAs scan for every patient. The CT dose index of volume (CTDIvol) and effective dose (ED) during non-contrast phase and portal venous phase were recorded. The CT value, standard deviation (SD), signal noise ratio (SNR) and contrast noise ratio (CNR) were measured in the liver parenchyma, spleen parenchyma and portal venous trunk.Results The CTDIvol and ED of spectrum scanning were less than 120 kVp scan but there was no statistical difference (P>0.05). The SD of group B GSI imaging was less than group A 120 kVp (P<0.05), while the SNR was greater than group A. The SD of group A GSI portal venous phase in the liver, spleen and portal vein was less than group B 120 kVp (P<0.05).ConclusionThe optimized energy spectrum scanning protocol can reduce radiation dose with quality of single energy image from the energy spectrum equal to or better than the conventional 120 kVp scanning protocol. Personalized energy spectrum scan protocol provides multi-parameter diagnosis and multi-application platform and can be used routinely in the upper abdomen scan.