Objective This study conducted molecular biological identification of the viruses carried by Culex pipiens pallens specimens collected in Shunyi District, Beijing in 2023, and observed the changes in the infection rate of the viruses carried by Cx. pipiens pallens at different collection times. Methods Cx. pipiens pallens were collected using carbon dioxide mosquito traps. The mosquito samples were ground in batches and analyzed by molecular biology technologies. The virus infection rate at different collection times was analyzed statistically. Results 17 strains of Culex pipiens pallens densovirus(CppDNV)were identified from Cx. pipiens pallens samples collected in Shunyi District, Beijing, in 2023. The nucleotide sequence analysis of the virus genome coding region showed that CppDNV was a single-stranded DNA virus with a total length of 3 335 nt, encoding 2 non-structural proteins(NS1, NS2)and 1 capsid protein(VP). The nucleotide(amino acid)sequence lengths of the three proteins were 2 376 nt(791 aa),1 092 nt(363 aa)and 1 071 nt(356 aa), respectively. Phylogenetic analysis showed that CppDNV was located in genus Brevihamaparvovirus. Statistical analysis showed no significant difference in infection rates across collection times(χ2=4.429, P=0.194). Conclusions CppDNV was identified in Cx. pipiens pallens in Beijing, and it was stably maintained in this natural population.

Objective: To investigate the incidence and influencing factors of new onset suicidal behaviors among junior and senior high school students, so as to provide evidence for early warning and intervention. Methods: Using a cluster sampling method, baseline data were collected from September to November 2023 among 2 379 adolescents selected from 2 junior high schools, 2 general senior high schools and 2 vocational senior high schools in Wuhan, Hubei Province, with follow up carried out from September to November 2024. Data were collected using the School Adaptation Scale, the Essential Resilience Scale, the Personal Social Support Scale, the Adverse Childhood Experiences Questionnaire, the Adolescent Life Events Scale, the Pittsburgh Sleep Quality Index, the Center for Epidemiologic Studies Depression Scale, and the Columbia-Suicide Severity Rating Scale. Multivariate Logistic regression analysis was used to identify factors influencing new onset suicidal behavior among junior and senior high school students. Results: Among junior and senior high school students without suicide risk at baseline, 53.55% remained stable risk free during follow up, while 13.28% developed new suicidal behavior during follow up, of which suicidal ideation, suicide plan and suicide attempts accounted for 11.69%, 8.83% and 6.52%, respectively. Multivariate Logistic regression revealed that increased depressive symptoms at follow up elevated the risk of overall new onset suicidal behaviors ( OR =4.14), ideation ( OR = 4.59), plans ( OR =4.24), and attempts ( OR =4.09); poor sleep quality also increased the risk of overall new onset suicidal behaviors ( OR =2.23), plans ( OR =2.03), and attempts ( OR =2.65) (all P <0.05). Non boarding junior and senior high school students had lower risks of overall new onset suicidal behaviors and ideation ( OR=0.70 and 0.49, respectively); secondary school students with academic performance ranking in the top 20%-30% of their class had a lower risk of new onset ideation ( OR =0.27); and those whose place of origin was outside the city had a lower risk of new onset plans ( OR =0.49) (all P <0.05). Conclusions New onset suicidal behaviors among junior and senior high school students exhibit dynamic and stage specific differences. Depressive symptoms serve as a common core risk factor across all stages, whereas sleep quality, academic performance, boarding status, and place of origin exert differential influences at distinct stages.

ObjectiveTo clarify the independent and synergistic effects of dyslipidemia in the progression of hepatic steatosis in metabolic dysfunction-associated fatty liver disease （MAFLD）. MethodsA total of 7 697 participants who underwent physical examination in Beijing Friendship Hospital， Capital Medical University， from January 2022 to December 2024 were enrolled， and finally 2 177 patients with MAFLD were enrolled as subjects. Transient elastography was used to quantify the severity of hepatic steatosis （grades S1-S3）. The multivariable ordinal Logistic regression analysis was used to investigate the independent and synergistic associations of serum triglyceride （TG）， high-density lipoprotein cholesterol （HDL-C）， and low-density lipoprotein cholesterol （LDL-C） with the severity of hepatic steatosis， and their interactions and potential nonlinear relationships with metabolic factors were also examined. One-way analysis of variance or Kruskal-Wallis H test was used for comparison of continuous data between groups， and chi-square test was used for comparison of categorical data between groups. ResultsAn increase in TG （odds ratio ［OR］=1.77， 95% confidence interval ［CI］： 1.48 — 2.10， P<0.001） and a reduction in HDL-C （OR=1.35， 95%CI： 1.11 — 1.65， P=0.003） were independently associated with a greater severity of hepatic steatosis， with the strongest association when both abnormalities coexisted （OR=2.40， 95%CI： 1.87 — 3.07， P<0.001）. The dose-response relationship analysis further revealed a nonlinear threshold effect of TG on hepatic steatosis at the threshold of 1.51 mmol/L （P_nonlinearity=0.001）， below which the severity of steatosis increased more rapidly with the increase in TG concentration （P=0.001）. The subgroup analysis showed that the association between the reduction in HDL-C and the severity of steatosis was observed only in males， young adults （aged <45 years）， and metabolically healthier subgroups （without diabetes， obesity， hyperuricemia or hypertension）. Significant interactions were observed between the presence or absence of obesity and the abnormal levels of TG and HDL‑C （both P_interaction<0.05）. The association of the increase in LDL-C with steatosis was confined to specific subgroups （without obesity or hyperuricemia）. ConclusionThe increase in TG and the reduction in HDL-C are independently associated with the severity of hepatic steatosis in MAFLD. The synergistic effect of blood lipids and their interactions with metabolic factors may further refine risk stratification， so as to provide a basis for precise management of MAFLD.

Objective To observe the effects of electroacupuncture(EA)on TGF-β1/Smads signaling pathway and epithelial-mesenchymal transition(EMT)related proteins in rats with neurogenic bladder(NB)after spinal cord injury;To explore the possible mechanism of EA in improving NB fibrosis.Methods Totally 36 female SD rats were randomly selected,with 10 rats in the sham-operation group and the remaining 26 rats undergoing complete transection of the spinal cord beneath the T8 vertebrae to establish a NB rat model.The modeling rats were randomly divided into model group and EA group,with 10 rats in each group.EA group was applied to"Ciliao","Zhongji"and"Sanyinjiao",20 min per time,once a day for 7 days.The general condition of the rats in each group was observed,the ultrasound index of the bladder was detected by ultrasound technique,the bladder function of the rats was detected by urodynamics,the body mass of the rats and the wet weight of the bladder were recorded,and the bladder index was calculated.HE staining was used to observe bladder tissue morphology,the degree of bladder tissue fibrosis and bladder wall thickness were detected by Masson staining.The positive expressions of E-cadherin,N-cadherin and Vimentin in bladder tissue were detected by immunohistochemistry.The protein expressions of TGF-β1,p-Smad2/3,E-cadherin,N-cadherin and Vimentin were detected by Western blot.Results Compared with the sham-operation group,the upper and lower diameter,anteroposterior diameter,transverse diameter,bladder volume of the model group significantly increased(P<0.001),the maximum bladder pressure,leak point pressure difference,perfusion time and maximum bladder capacity significantly increased(P<0.001),the bladder index increased significantly(P<0.001),the bladder epithelial cells were thickened and arranged irregularly,the bladder collagen volume fraction and bladder wall thickness significantly increased(P<0.001),the expressions of TGF-β1,p-Smad2/3,N-cadherin and Vimentin in bladder tissue increased(P<0.01),and the expression of E-cadherin decreased(P<0.001).Compared with the model group,the upper and lower diameter,anteroposterior diameter,transverse diameter,bladder volume of the EA group decreased significantly(P<0.05),the maximum bladder pressure,leak point pressure difference,perfusion time and maximum bladder capacity significantly decreased(P<0.05),the bladder index significantly decreased(P<0.05),the thickness of the bladder epithelial cell layer became thinner and arranged more neatly,and the bladder collagen volume fraction and bladder wall thickness of the bladder were significantly reduced(P<0.05),the expressions of TGF-β1,p-Smad2/3,N-cadherin and Vimentin in bladder tissue significantly decreased(P<0.05),and the expression of E-cadherin significantly increased(P<0.05).Conclusion EA may reduce the EMT of bladder epithelial cells and decrease the degree of bladder tissue fibrosis by inhibiting the activation of the TGF-β1/Smads signaling pathway,thereby improving bladder function in NB rats after spinal cord injury.

As a new generation of time-of-flight mass spectrometry,multiple-reflection time-of-flight mass spectrometry(MR-TOF-MS)has been increasingly applied in the fields such as nuclear physics,chemistry,and biology due to its ultra-high resolution and rapid analysis capabilities.However,the analytical performance of MR-TOF-MS largely depends on the ion bunch state entering the mass analyzer.In this study,a rectangular ion trap(RIT)was developed,designed and processed using printed circuit board technology,as an ion accumulating and focusing device for MR-TOF mass analyzer.Compared to traditional ion traps composed of two sets of planar electrodes,this RIT had higher voltage utilization efficiency,resulting in more efficient ion collection and focusing.The ions were cooled to a sufficiently small bunch for precise mass measurement with MR-TOF-MS mass spectrometry in only 1 ms of cooling time in the RIT,then orthogonally ejected to the MR-TOF mass spectrometer for mass analysis.Experimental results indicated that the working cycle,ion flux,and ion focusing state of the RIT fully met the requirements of the MR-TOF mass analyzer.When coupled with the MR-TOF mass analyzer,the RIT enabled MR-TOF-MS to achieve a mass resolution of 1.5×105.

The continuous accumulation of plastic waste such as polyethylene in the environment has caused serious environmental pollution issues.Considering the high similarity in the molecular structure of petroleum and polyolefin,it is feasible to apply rare earth-zeolite catalysts in polyolefin plastic upcycling,which is commonly used in fluid catalytic cracking(FCC)in the field of petroleum refining.In this study,Ce-modified HY(Ce-HY)zeolites were synthesized and characterized by a series of analytical methods,such as high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM),Fourier infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),etc.When introducing 5% Ce species into HY zeolites,the 5Ce-HY showed excellent catalytic performance in the catalytic cracking of low-density polyethylene(LDPE),which achieved 98.4% LDPE conversion with 91.5% selectivity of gaseous alkanes at 300℃,and 75.4% of them were isoparaffins.In addition,the effect of the location of rare earth species in Y zeolites on the catalytic performance was explored by fine X-ray diffraction(XRD)in the range of 11°-13°and in situ-Raman analyses.The Ce species located in the supercage of Y zeolites were more important,which enhanced the adsorption capacity and accessibility of substrate molecules,thus facilitating the entire catalytic cracking process.This method could be used to detect the location of rare earth elements in Y zeolites to understand the mechanism of rare earth catalysis.

Sarin(GB)is a typical representative of nerve agents with high toxicity,and very low amount can cause death.GB can cause water and atmospheric environment poisoning,so the detection of GB in water and air is of great significance.In this work,a colorimetric sensor array(CSA)based on GB inhibition of cholinesterase activity was constructed to detect GB with high selectivity.A 4×4 colorimetric array was constructed using acetylcholinesterase(AChE),butyryl cholinesterase(BuChE)and the corresponding substrate acetylthiocholine iodide(S-ACh),butyryl thiocholine iodide(S-BCh),acetylcholine chloride(ACh),butyryl choline chloride(BCh)and 2,6-dichloroindophenol ethyl ester(DCIE).The linear curve of the sensor was Y=131.3×lgC+271.6(R2=0.997),where Y was the array response Euclidean distance,C was the concentration of GB(mg/L),the linear range was 0.03?0.32 mg/L,and the detection limit was 27.6 μg/L.The method could effectively distinguish chemical warfare agents(CWA)such as VX,Soman(GD),mustard gas(HD),Louie reagent(L),and had high anti-interference ability,sensitivity and good repeatability.It was successfully applied to the detection of GB in simulated water and simulated air samples,and the sample recovery rate was 97.2% ?100.9%.This method would be potentially applied to the field rapid detection of nerve agents.

Hepatocellular carcinoma(HCC)is one of common cancer that seriously endangers human health.Designing methods for early,rapid,and accurate diagnosis of HCC has become the key point.Golgi protein 73(GP73),a novel potential biomarker for HCC,is crucial for diagnosis and treatment of HCC.In this study,a colorimetric sensor with rapidity,smplicity and high specificity was established for detection of GP73 based on peroxidase-like activity of hemin-reduced graphene oxide-manganese dioxide(H-rGO-MnO2).The H-rGO-MnO2-GP73Apt1 signal probe was synthesized by carboxyl of H-rGO-MnO2 nanozyme and amination of GP73 aptamer(GP73Apt1)though amide reaction.In the presence of GP73,the sulfhydryl-modifed GP73 aptamer(GP73Apt2),as the capture probe,and the signal probe both specifically recognized GP73,forming a sandwich structure(GP73Apt2-GP73-H-rGO-MnO2-GP73Apt1).This structure could catalyze the oxidation of H2O2 to produce hydroxyl radical(·OH),thereby oxidizing the colorless phthalenediamine(OPD)into the yellow 2,3-diaminophenazine(DPA).The quantitative detection of GP73 was achieved by measuring the characteristic absorbance of DPA at 450 nm.In the GP73 concentration range of 10-150 ng/mL,there was a good linear relationship between the DPA absorbance at 450 nm(A450 nm)and the GP73 concentration under optimal conditions.The linear equation was A450 nm=0.00321CGP73+0.8988,with the correlation coefficient(R2)of 0.9960 and the detection limit(LOD)of 5.38 ng/mL.The colorimetric sensor was applied to detection of GP73 in human serum samples,with recoveries of 88.4%?98.8%.This sensor showed high specificity,sensitivity,and stability,and had potential for clinical detection of GP73,providing a new approach for the early diagnosis of HCC.

In recent years,micro photoionization detectors(μPID),with their rapid response speed and excellent sensitivity,have attracted widespread attention in both scientific research and industry.This study developed a portable gas chromatograph based on μPID technology(GC-μPID),and examined its key performance characteristics such as reproducibility,sensitivity,and online analytical capability.The results showed that the method's relative standard deviation(RSD)was controlled within 2.7%,demonstrating good reproducibility;for the standard curves of 27 kinds of volatile organic compounds(VOCs),the linearity was excellent(R2≥0.99),with detection limits of≤10 μg/m3 and benzene series compounds reaching detection limits as low as 0.5 μg/m3.In field applications at an industrial park,this method successfully identified and quantified 17 kinds of VOCs,accurately capturing their diurnal concentration variations.The results above validated that the method developed here had the capability of onsite real-time monitoring and provided an effective tool for in situ monitoring atmospheric pollutants.

Phosgene is a highly reactive chemical substance and a prevalent chemical warfare agent,and it is vitally important for rapid and accurate detection of phosgene to counteract terrorist threats and industrial accidents.In this work,a phosgene probe,designated as SX-Pho,which incorporated benzimidazole and hydroxyl groups as recognition motifs,was prepared through Suzuki coupling and Debus-Radziszewski methodologies to incorporate an electron-donating carbazole moiety.This probe exhibited a large Stokes shift(Approximately 130 nm).Upon exposure to triphosgene/triethylamine conditions(in situ phosgene generation),the fluorescence emission of probe at 470 nm underwent significant quenching,with a 20-fold reduction in intensity,while the fluorescence lifetime decreased from 3.30 ns to 3.06 ns.Concentration titration experiments demonstrated that SX-Pho achieved a lower detection limit of 57.8 nmol/L with high specificity and interference resistance.Preton nuclear magnetic resonance spectroscopy(1H NMR),high-resolution mass spectrometry,and density functional theory(DFT)calculations confirmed the cyclization reaction between hydroxyl groups,imines,and phosgene.The extent of overlap between the highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)was notably decreased,leading to the suppression of radiative transitions.The energy gap underwent a reduction of 0.43 eV,while the non-radiative transition was augmented,resulting in fluorescence quenching and achieving rapid detection of phosgene.Based on this,probe-loaded test strips were prepared.The color change under 365 nm illumination allowed visual discrimination of phosgene at concentrations below 20 μL/L.Furthermore,using a smartphone's built-in RGB application to measure the intensity of the blue(B)channel after the test strips were exposed to phosgene enabled both qualitative and quantitative detection.The detection range was 1.82-50 μL/L,with a limit of detection(LOD)of 1.814 μL/L.