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Science China Chemistry 2024年第2期67卷 551-557页

作者： Zhenzhen wu jing Wang Lili Liu Shang Guo Juan Li Xianming Zhang Shanxi Institute for Functional Food Shanxi Agricultural UniversityTaiyuan030031China Institute of Crystalline Materials Shanxi UniversityTaiyuan030006China Key Laboratory of Interface Science and Engineering in Advanced Materials College of ChemistryTaiyuan University of TechnologyTaiyuan030024China

Covalent organic frameworks(COFs) are a potential platform for carbon dioxide(CO_(2)) conversion owing to their periodic permanent porosity,adjustable structure,and chemical stability.For good catalytic performance in CO_(2) conversion,collaborative multifunctions should be strategically integrated into the catalytic system design and construction.In this study,a four-in-one high-efficiency catalyst was synthesized and tested for CO_(2) cycloaddition to form cyclic carbonate.The obtained Tp-MPB-BrCOF had a high nitrogen content,which enhanced its CO_(2) affinity through substantial Lewis acid-base or dipole-quadrupole interactions;moreover,the acid(protons transferring from oxygen(–OH) to nitrogen(–NH)),hydrogen bond donor(hydroxyl group),and Br-(nucleophile group) served as three active sites,further improving the catalyst activity.These results provide a basis for designing efficient and stable CO_(2)-conversion catalysts.

关键词： covalent organic framework C2-phenyl-substituted benzimidazolium CO_(2)conversion four-in-one catalyst

Evolution of tribo-magnetization during sliding of ferromagnetic materials

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Friction 2024年第5期12卷 906-918页

作者： Fumin GAO Laibin ZHANG Jin ZHOU Yi XIONG jing wu Jianchun FAN China University of Petroleum-Beijing Beijing102249China Key Laboratory of Oil and Gas Safety and Emergency Technology Ministry of Emergency ManagementBeijing102249China

Sliding-induced subsurface microstructure evolution is believed to be decisive for determining the friction and wear performance of metallic contacts as well as the development of tribo-magnetization.This expects to develop a new prediction method of wear state by elucidating the correlation between subsurface microstructure evolution and corresponding magnetic domain changes.Herein,subsurface microstructure evolution including crystal and magnetic domain under tribological action is investigated experimentally.Our results demonstrate that dislocation mediated plastic deformation decisively influences microstructural changes during tribological contact,further determining the magnetic domain structure.Specifically,sliding-induced plastic deformation causes an increase in the width of magnetic domains,but depth-dependent derived microstructure formed under severe plastic deformation such as the refined grains and sub-grains,in turn,promoted the refinement of magnetic domains and their discontinuity,forming depth-dependent magnetic domain structure.These results are helpful to clarify the evolution of tribo-magnetization and the pinning effect of dislocations on magnetic domains.

关键词： tribology magnetic domain microstructure tribo-magnetization dislocations

Chain Dynamics Heterogeneity in Plasticized Poly(vinyl butyral)(PVB) as Elucidated by Solid-State NMR

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Chinese Journal of Polymer Science 2024年第1期42卷 113-124,I0010页

作者： jing Lv Xu Chen Zi-Shuo wu Ya-Hui Li Wei Chen National Synchrotron Radiation Laboratory Anhui Provincial Engineering Laboratory of Advanced Functional Polymer FilmCAS Key Laboratory of Soft Matter ChemistryUniversity of Scienceand Technology of ChinaHefei 230026China

The chain dynamics heterogeneity of the poly(vinyl butyral)(PVB) plasticized by triethylene glycol bis(2-ethylhexa noate)(TEG-EH) was investigated by various solid-state NMR techniques.The plasticized PVB shows two domains in distinct molecular dynamics differences,namely,rigid and soft domains,where the latter is the plasticizer-rich domain.The time domain low field NMR was first used to investigate the dynamics heterogeneity of the plasticized PVB,and the results show the decreasing activated energy of components in the soft domain of plasticized PVB(E_a=20.2 kJ/mol) as compared with that of the pristine one(E_a=24.3 kJ/mol).Detailed dynamics heterogeneity was obtained by high-field NMR with site-specific features.The quadrupole-echo ~2H-NMR was adopted to elucidate the dynamics heterogeneity of the vinyl alcohol(VA) units,where only the hydroxyl group of VA is deuterated.The ~1H-^(13)C WISE NMR spectra show that there is not much difference in the mobility of the VB unit in PVB with and without plasticizer,whereas the glass transition temperature differed by approximately 53℃.This is further supported by Torchia's T_1 relaxation measurements.The origin of such an unusual phenomenon is attributed to the critical role of the remaining VA(~22%) in the soft domain,where the VA units locally aggregate through hydrogen bonding.Also,the existence of a mobility gradient in the VB unit has been demonstrated.Moreover,the mobility difference for VB with different stereo-geometry(meso or racemic conformation) is observed for the first time.This indicates the importance of modulating the ratio of meso over racemic VB for controlling the macroscopic perfo rmance of PVB.

关键词： Poly(vinyl butyral) Dynamics heterogeneity Plasticizer Solid state NMR

Risk Factors Asscociated with Hypokalemia during Postanesthesia Recovery and Its Impact on Outcomes in Gynecological Patients:A Propensity Score Matching Study

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Current Medical Science 2024年第2期44卷 441-449页

作者： Bei-bei WANG Li HU Xin-yue HU Dong HAN jing wu Department of Anesthesiology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Institute of Anesthesia and Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China Key Laboratory of Anesthesiology and Resuscitation(Huazhong University of Science and Technology) Ministry of EducationWuhan430022China

Objective:This study aimed to explore the risk factors and outcomes of hypokalemia during the recovery period from anesthesia in the gynecological population.Methods:This retrospective cohort study included 208 patients who underwent gynecological surgery at our institution between January 2021 and March 2022.Data were collected for each patient,including demographics,disease status,surgical data,and clinical information.Preoperative bowel preparation,postoperative gastrointestinal function,and electrolyte levels were compared between the two groups using propensity score matching(PSM).Results:The incidence of hypokalemia(serum potassium level<3.5 mmol/L)during the recovery period from anesthesia was approximately 43.75%.After PSM,oral laxative use(96.4%vs.82.4%,P=0.005),the number of general enemas(P=0.014),and the rate of≥2 general enemas(92.9%vs.77.8%,P=0.004)were identified as risk factors for hypokalemia,which was accompanied by decreased PaCO2 and hypocalcemia.There were no significant differences in postoperative gastrointestinal outcomes,such as the time to first flatus or feces,the I-FEED score(a scoring system was created to evaluate impaired postoperative gastrointestinal function),or postoperative recovery outcomes,between the hypokalemia group and the normal serum potassium group.Conclusion:Hypokalemia during postanesthesia recovery period occurred in 43.75%of gynecological patients,which resulted from preoperative mechanical bowel preparation;however,it did not directly affect clinical outcomes,including postoperative gastrointestinal function,postoperative complications,and length of hospital stay.

关键词： hypokalemia gynecological surgery postanesthesia recovery perioperative electrolyte disturbances postoperative recovery

Effects of herbicide butachlor application on the growth of periphytic biofilms and nitrogen loss in paddy systems

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Pedosphere 2024年第1期34卷 211-221页

作者： Yanhui ZHAO Mingjun LEI Liandong jing Fan XIA Meixia YAN Jiantong LIU Yonghong wu Yunli wu Chenxi wu Ecology and Environment Monitoring and Scientific Research Center Yangtze Basin Ecology and Environment AdministrationMinistry of Ecological and EnvironmentWuhan 430010China College of Chemistry and Environmental Protection Engineering Southwest Minzu UniversityChengdu 610041China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The application of butachlor as an herbicide in paddy fields is widely practiced,aiming to increase rice yield by directly or indirectly influencing the paddy environment.Periphytic biofilms,which form at the soil-water interface in paddy fields,are complex bioaggregates that play an important role in nitrogen (N) cycling.The objective of this study was to investigate the effect of butachlor on periphytic biofilm growth and N cycling under both light and dark conditions in the laboratory.The results revealed that butachlor application hindered the growth of periphytic biofilms and led to the dominance of Cyanobacteria as the primary prokaryotes,while inhibiting the development of eukaryotic Trebouxiophyceae.Furthermore,the application of butachlor reduced the richness and diversity of prokaryotes,but increased those of eukaryotes in periphytic biofilms.The light treatments exhibited higher total N loss because light favored periphytic biofilm growth and enhanced ammonium (NH_(4)^(+)) assimilation and nitrification.Additionally,butachlor application resulted in the increased retention of NH_(4)^(+)-N and nitrate (NO_(3)^(-))-N and an increase in N loss via denitrification.The abundances of functional genes encoding enzymes such as ammonia monooxygenase,nitrite reductase,and nitrous oxide reductase were increased by butachlor application,favoring nitrification and denitrification processes.Overall,the results suggest that butachlor application leads to an increase in total N loss mainly through denitrification in paddy systems,particularly in the presence of periphytic biofilms.Thus,the results may provide valuable insights into the changes in periphytic biofilm growth and N cycling induced by butachlor,and future studies can further explore the potential implications of these changes in paddy soils.

关键词： ammonia-oxidizing bacteria amoA denitrification denitrifying bacteria nirK nitrification nitrogen cycling nosZ volatilization

HHO optimized support vector machine classifier for traditional Chinese medicine syndrome differentiation of diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 991-1000页

作者： Li Xiao Cheng-wu Wang Ying Deng Yi-jing Yang jing Lu Jun-Feng Yan Qing-Hua Peng School of Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina School of Informatics Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Key Laboratory for Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Chinese Medicine Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina Hunan Provincial Engineering and Technological Research Center for Prevention and Treatment of Ophthalmology and Otolaryngology Diseases with Chinese Medicine and Protecting Visual Function Hunan University of Chinese MedicineChangsha 410208Hunan ProvinceChina

AIM:To develop a classifier for traditional Chinese medicine(TCM)syndrome differentiation of diabetic retinopathy(DR),using optimized machine learning algorithms,which can provide the basis for TCM objective and intelligent syndrome differentiation.METHODS:Collated data on real-world DR cases were collected.A variety of machine learning methods were used to construct TCM syndrome classification model,and the best performance was selected as the basic model.Genetic Algorithm(GA)was used for feature selection to obtain the optimal feature combination.Harris Hawk Optimization(HHO)was used for parameter optimization,and a classification model based on feature selection and parameter optimization was constructed.The performance of the model was compared with other optimization algorithms.The models were evaluated with accuracy,precision,recall,and F1 score as indicators.RESULTS:Data on 970 cases that met screening requirements were collected.Support Vector Machine(SVM)was the best basic classification model.The accuracy rate of the model was 82.05%,the precision rate was 82.34%,the recall rate was 81.81%,and the F1 value was 81.76%.After GA screening,the optimal feature combination contained 37 feature values,which was consistent with TCM clinical practice.The model based on optimal combination and SVM(GA_SVM)had an accuracy improvement of 1.92%compared to the basic classifier.SVM model based on HHO and GA optimization(HHO_GA_SVM)had the best performance and convergence speed compared with other optimization algorithms.Compared with the basic classification model,the accuracy was improved by 3.51%.CONCLUSION:HHO and GA optimization can improve the model performance of SVM in TCM syndrome differentiation of DR.It provides a new method and research idea for TCM intelligent assisted syndrome differentiation.

关键词： traditional Chinese medicine diabetic retinopathy Harris Hawk Optimization Support Vector Machine syndrome differentiation

Application of Global Leadership Initiative on Malnutrition criteria in patients with liver cirrhosis

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Chinese Medical Journal 2024年第1期137卷 97-104页

作者： Minjie Jiang Juan Chen Muchen wu jing wu Xiaotong Xu Juan Li Can Liu Yaping Zhao Xin Hua Qinghua Meng Department of Hepatology Beijing You-An HospitalCapital Medical UniversityBeijing 100069China Beijing Institute of Hepatology Beijing 100069China Department of Medical Oncology Beijing You-An HospitalCapital Medical UniversityBeijing 100069China Department of Nutrition Beijing You-An HospitalCapital Medical UniversityBeijing 100069China

Background:The Global Leadership Initiative on Malnutrition(GLIM)criteria were published to build a global consensus on nutritional diagnosis.Reduced muscle mass is a phenotypic criterion with strong evidence to support its inclusion in the GLIM consensus criteria.However,there is no consensus regarding how to accurately measure and define reduced muscle mass in clinical settings.This study aimed to investigate the optimal reference values of skeletal muscle mass index for diagnosing sarcopenia and GLIM-defined malnutrition,as well as the prevalence of GLIM-defined malnutrition in hospitalized cirrhotic patients.Methods:This retrospective study was conducted on 1002 adult patients with liver cirrhosis between January 1,2018,and February 28,2022,at Beijing You-An Hospital,Capital Medical University.Adult patients with a clinical diagnosis of liver cirrhosis and who underwent an abdominal computed tomography(CT)examination during hospitalization were included in the study.These patients were randomly divided into a modeling group(cohort 1,667 patients)and a validation group(cohort 2,335 patients).In cohort 1,optimal cut-off values of skeletal muscle index at the third lumbar skeletal muscle index(L3-SMI)were determined using receiver operating characteristic analyses against in-hospital mortality in different gender groups.Next,patients in cohort 2 were screened for nutritional risk using the Nutritional Risk Screening 2002(NRS-2002),and malnutrition was diagnosed by GLIM criteria.Additionally,the reference values of reduced muscle mass in GLIM criteria were derived from the L3-SMI values from cohort 1.Multivariate logistic regression analysis was used to analyze the association between GLIM-defined malnutrition and clinical outcomes.Results:The optimal cut-off values of L3-SMI were 39.50 cm 2/m 2 for male patients and 33.06 cm 2/m 2 for female patients.Based on the cut-off values,31.63%(68/215)of the male patients and 23.3%(28/120)of the female patients had CT-determined sarcopenia in cohort 2.The prevalence of GL

关键词： Malnutrition Liver cirrhosis Sarcopenia Clinical outcomes GLIM criteria

Mars exploration——In situ K-Ar dating of jarosite

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Science China Earth Sciences 2024年第3期67卷 641-656页

作者： jing YANG Dewen ZHENG Ying wu Hong CHEN Li YANG Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

Dynamic emission characteristics and control strategies of air pollutants from motor vehicles in downtown Beijing,China

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Journal of Environmental Sciences 2024年第2期136卷 637-646页

作者： Yan Shen Tongran wu Aiping Lian Jie Gao Fei Peng Guohua Song Xuefang wu Yangyang Cui Xinyu Liu Yunfei Wan jing Yan Yifeng Xue National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China Beijing Municipal Ecology and Environment Bureau Beijing 100048China Beijing Jiaotong University Beijing 100091China

This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle air pollutants in downtown Beijing in 2021 was established,and the impact of these emissions on air quality was simulated and quantified,and different emission reduction control scenarios were proposed to evaluate their environmental improvement effects and explore measures to mitigate the impact of pollution emissions.The results show that the high traffic flow and the structure of the motor vehicle emissions in downtown Beijing are the main causes of severe motor vehicle pollution.Monitoring data shows that traffic flow in central Beijing is dominated by small passenger vehicles,while the vehicle mix is better than in other regions,with 72.0%of vehicles meeting"National V"or higher emission standards.However,to achieve higher air quality goals,further reducing vehicle emissions is necessary.Based on dynamic traffic flow,the average daily emissions of nitrogen oxides(NOX),particulate matters(PM_(2.5))and volatile organic compounds(VOC)from motor vehicles in central Beijing are 17.7 tons,0.6 tons and 14.0 tons,respectively,accounting for 23.0%of the city’s average daily motor vehicle emissions.If a zero-emission zone for motor vehicles were implemented in central Beijing,the annual average emission level of pollutants will be reduced by 10.4%to 21.0%.The designation of ultra-low emission zones for motor vehicles could be effective in improving the air quality in the center of Beijing.

关键词： Motor vehicle Air pollutant Emission characteristics Control strategy Beijing

Decreased eggshell strength caused by impairment of uterine calcium transport coincide with higher bone minerals and quality in aged laying hens

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1258-1277页

作者： Yu Fu Jianmin Zhou Martine Schroyen Haijun Zhang Shugeng wu Guanghai Qi jing Wang Key Laboratory of Feed Biotechnology Ministry of Agriculture and Rural AffairsInstitute of Feed ResearchChinese Academy of Agricultural SciencesBeijing 100081China Precision Livestock and Nutrition Laboratory Gembloux Agro‑Bio TechTERRA Teaching and Research CentreUniversity of LiegeGembloux B‑5030Belgium

Background Deteriorations in eggshell and bone quality are major challenges in aged laying hens.This study compared the differences of eggshell quality,bone parameters and their correlations as well as uterine physiologi-cal characteristics and the bone remodeling processes of hens laying eggs of different eggshell breaking strength to explore the mechanism of eggshell and bone quality reduction and their interaction.A total of 24074-week-old Hy-line Brown laying hens were selected and allocated to a high(HBS,44.83±1.31 N)or low(LBS,24.43±0.57 N)eggshell breaking strength group.Results A decreased thickness,weight and weight ratio of eggshells were observed in the LBS,accompanied with ultrastructural deterioration and total Ca reduction.Bone quality was negatively correlated with eggshell quality,marked with enhanced structures and increased components in the LBS.In the LBS,the mammillary knobs and effective layer grew slowly.At the initiation stage of eggshell calcification,a total of 130 differentially expressed genes(DEGs,122 upregulated and 8 downregulated)were identified in the uterus of hens in the LBS relative to those in the HBS.These DEGs were relevant to apoptosis due to the cellular Ca overload.Higher values of p62 protein level,caspase-8 activity,Bax protein expression and lower values of Bcl protein expression and Bcl/Bax ratio were seen in the LBS.TUNEL assay and hematoxylin-eosin staining showed a significant increase in TUNEL-positive cells and tissue damages in the uterus of the LBS.Although few DEGs were identified at the growth stage,similar uterine tissue damages were also observed in the LBS.The expressions of runt-related transcription factor 2 and osteocal-cin were upregulated in humeri of the LBS.Enlarged diameter and more structural damages of endocortical bones and decreased ash were observed in femurs of the HBS.Conclusion The lower eggshell breaking strength may be attributed to a declined Ca transport due to uterine tissue damages,which could affect eggshell calcification and lead to

关键词： Bone parameter Calcium transport Eggshell quality Laying hen Tissue damage

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