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Corrosion Behavior of Graphene Nanosheets Reinforced Magnesium Matrix Composites in Simulated Body Fluids

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 525-536页

作者： Liwen Chen Jianhui jing Lulu Zhang jing Li Weipeng Chen Limin Li Yuan zhao hua Hou Yuhong zhao School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051China Shanxi Key Laboratory of Advanced Manufacturing Technology School of Mechanical EngineeringNorth University of ChinaTaiyuan 030051China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Magnesium(Mg)alloy is considered as a promising biodegradable implant material but restricted to rapid degradation.Here,the new strategies based on thixomolding process had been explored to utilize the outstanding anti-permeability of graphene nanosheets(GNPs)while inhibit its galvanic corrosion with the matrix,so as to improve the corrosion resistance of composites.The agglomerate of GNPs with 0.9 wt%content is the main reason for the deterioration of corrosion performance due to the formation of micro-galvanic corrosion.The grain refinement of composites with 0.6 wt%content had positive effects on the better corrosion resistance.After process adjusting,the unique distributions of GNPs along grain boundaries play a vital role in improving the corrosion resistance.It can be ascribed to the following mechanisms:(I)The barriers can be established between the Mg matrix and corrosive medium,hence blocking the charge transfer at the interface;(II)The GNPs can effectively promote apatite deposition on the Mg matrix,leading to form dense apatite layers and prevent the further invasion of SBF;(III)The GNPs acting as reinforcements exists in the corrosion layer and apatite layer,impede the apatite layer falling off from the Mg matrix.These findings broaden the horizon for biomedical applications in Mg matrix composites to realize desired performances.

关键词： Magnesium matrix composite Graphene nanosheets Corrosion resistance

New pimarane diterpenoids with antibacterial activity from fungus Arthrinium sp.ZS03

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Chinese Journal of Natural Medicines 2024年第4期22卷 356-364页

作者： zhao Songfeng jing Ziwei Department of Pharmacy the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

A comprehensive chemical study of the endophytic fungus Arthrinium sp. ZS03, associated with Acorus tatarinowii Schott, yielded eleven pimarane diterpenoids (compounds 1–11), including seven novel compounds designated arthrinoids A–G (1–7). The determination of their structures and absolute configurations was achieved through extensive spectroscopic techniques, quantum chemical calculations of electronic circular dichroism (ECD), and single-crystal X-ray diffraction analysis. Furthermore, 7 demonstrated inhibitory activity against Klebsiella pneumoniae, comparable to the reference antibiotic amikacin, with a minimum inhibitory concentration (MIC) of 8 μg·mL^(−1).

关键词： Arthrinium sp.ZS03 Pimarane diterpenoids Structural elucidation Antibacterial activity

Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan Qin Sheng-Da zhao Zhi-Xin Liu jing Zhang Xing-hua Zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

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

Evaluation of the value of combined detection of tumor markers CA724,carcinoembryonic antigen,CA242,and CA19-9 in gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1737-1744页

作者： Chong-Mei Zhou Shao-hua zhao Department of Clinical Laboratory Henan Provincial People's HospitalZhengzhou 450003Henan ProvinceChina

BACKGROUND Gastric cancer is a global health concern that poses a significant threat to human well-being.AIM To detecting serum changes in carcinoembryonic antigen(CEA),carbohydrate antigens(CA)724,CA242,and CA19-9 expression among patients with gastric cancer.METHODS Eighty patients diagnosed with gastric cancer between January 2020 and January 2023 were included in the observation group,while 80 patients with benign gastric diseases were included in the control group.Both groups were tested for tumor markers(CA724,CEA,CA242,and CA19-9].Tumor marker indicators(CA724,CEA,CA242,and CA19-9)were compared between the two groups,assessing positive rates of tumor markers across various stages in the observation group.Additionally,single and combined detection of various tumor markers were examined.RESULTS The sensitivity,specificity,accuracy,positive predictive value,and negative predictive value observed for the combined detection of CA724,CEA,CA242,and CA19-9 were higher than those of CA724,CEA,CA242,and CA19-9 individually.Therefore,the combined detection of CA724,CEA,CA242,and CA19-9 has a high diagnostic accuracy and could reduce the occurrence of missed or misdiagnosed cases,facilitating the early diagnosis and treatment of patients.CONCLUSION CA724,CEA,CA242,and CA19-9 serum levels in gastric cancer patients significantly surpassed those in non-gastric cancer patients(P<0.05).Their combined detection can improve the diagnostic accuracy for gastric cancer,warranting clinical promotion.

关键词： Biomarkers Serum Gastric cancer Diagnostic value

Clinical observation of gastrointestinal function recovery in patients after hepatobiliary surgery

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 76-84页

作者： hua-Jun Zeng jing-jing Liu Ying-Chun Yang Department of General Practice Nanyang First People's HospitalNanyang 473000Henan ProvinceChina Department of Anesthesiology Chinese People’s Armed Police Force Hospital of BeijingBeijing 100027China Department of Anesthesiology Beijing Fengtai HospitalBeijing 100071China

BACKGROUND The liver is an important metabolic and digestive organ in the human body,ca-pable of producing bile,clotting factors,and vitamins.AIM To investigate the recovery of gastrointestinal function in patients after hepato-biliary surgery and identify effective rehabilitation measures.METHODS A total of 200 patients who underwent hepatobiliary surgery in our hospital in 2022 were selected as the study subjects.They were divided into a control group and a study group based on the extent of the surgery,with 100 patients in each group.The control group received routine treatment,while the study group re-ceived targeted interventions,including early enteral nutrition support,drinking water before gas discharge,and large bowel enema,to promote postoperative gastrointestinal function recovery.The recovery of gastrointestinal function was compared between the two groups.RESULTS Compared with the control group,patients in the study group had better recovery of bowel sounds and less accumulation of fluids in the liver bed and gallbladder fossa(P<0.05).They also had shorter time to gas discharge and first meal(P<0.05),higher overall effective rate of gastrointestinal function recovery(P<0.05),and lower incidence of postoperative complications(P<0.05).CONCLUSION Targeted nursing interventions(early nutritional support,drinking water before gas discharge,and enema)can effectively promote gastrointestinal function recovery in patients undergoing hepatobiliary surgery and reduce the incidence of complications,which is worthy of promotion.

关键词： Liver and gallbladder patients Gastrointestinal function Postoperative recovery

Association of prealbumin with short-term and long-term outcomes in patients with acute ST-segment elevation myocardial infarction

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Journal of Geriatric Cardiology 2024年第4期21卷 421-430页

作者： jing TAN Jin SI Ke-Ling XIAO Ying-hua ZHANG Qi hua jing LI Department of Cardiology Xuanwu Hospital Capital Medical UniversityBeijingChina Department of Geriatric Medicine Xuanwu Hospital Capital Medical UniversityNational Clinical Research Center for Geriatric DiseasesBeijingChina

BACKGROUND Prealbumin is considered to be a useful indicator of nutritional status. Furthermore, it has been found to be associated with severities and prognosis of a range of diseases. However, limited data on the association of baseline prealbumin level with outcomes of patients with acute ST-segment elevation myocardial infarction(STEMI) are available.METHODS We analyzed 2313 patients admitted for acute STEMI between October 2013 and December 2020. In-hospital outcomes and mortality during the 49 months(interquartile range: 26–73 months) follow-up period were compared between patients with the low prealbumin level(< 170 mg/L) and those with the high prealbumin level(≥ 170 mg/L).RESULTS A total of 114 patients(4.9%) died during hospitalization. After propensity score matching, patients with the low prealbumin level than those with the high prealbumin level experienced higher incidences of heart failure with Killip class Ⅲ(9.9%vs. 4.4%, P = 0.034), cardiovascular death(8.4% vs. 3.4%, P = 0.035) and the composite of major adverse cardiovascular events(19.2%vs. 10.3%, P = 0.012). Multivariate logistic regression analysis identified that the low prealbumin level(< 170 mg/L) was an independent predictor of in-hospital major adverse cardiovascular events(odds ratio = 1.918, 95% CI: 1.250–2.942, P = 0.003). The cutoff value of prealbumin level for predicting in-hospital death was 170 mg/L(area under the curve = 0.703, 95% CI: 0.651–0.754, P< 0.001;sensitivity = 0.544, specificity = 0.794). However, after multivariate adjustment of possible confounders, baseline prealbumin level(170 mg/L) was no longer independently associated with 49-month cardiovascular death. After propensity score matching, Kaplan-Meier survival curves revealed consistent results.CONCLUSIONS Decreased prealbumin level closely related to unfavorable short-term outcomes. However, after multivariate adjustment and controlling for baseline differences, baseline prealbumin level was not independently associated with an increased risk of long-term cardio

关键词： patients admitted infarction

PDOL-Based Solid Electrolyte Toward Practical Application:Opportunities and Challenges

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Nano-Micro Letters 2024年第7期16卷 109-141页

作者： hua Yang Maoxiang jing Li Wang Hong Xu Xiaohong Yan Xiangming He Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013People’s Republic of China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084People’s Republic of China

Polymer solid-state lithium batteries(SSLB)are regarded as a promising energy storage technology to meet growing demand due to their high energy density and safety.Ion conductivity,interface stability and battery assembly process are still the main challenges to hurdle the commercialization of SSLB.As the main component of SSLB,poly(1,3-dioxolane)(PDOL)-based solid polymer electrolytes polymerized in-situ are becoming a promising candidate solid elec-trolyte,for their high ion conductivity at room temperature,good battery elec-trochemical performances,and simple assembly process.This review analyzes opportunities and challenges of PDOL electrolytes toward practical application for polymer SSLB.The focuses include exploring the polymerization mechanism of DOL,the performance of PDOL composite electrolytes,and the application of PDOL.Furthermore,we provide a perspective on future research directions that need to be emphasized for commercialization of PDOL-based electrolytes in SSLB.The exploration of these schemes facilitates a comprehensive and profound understanding of PDOL-based polymer electrolyte and provides new research ideas to boost them toward practical application in solid-state batteries.

关键词： Poly(1,3-dioxolane) Solid electrolyte Polymerization mechanism Composite electrolyte Practical application

Atomic force microscopy-based nanoscale infrared techniques for liquid environments

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Science Bulletin 2024年第2期69卷 151-153页

作者： Jian Li jing Liang Mu-Hao Lan Xing-hua Xia State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Infrared(IR)light energy matches well with the vibration and rotation of chemical bonds in molecules,hence IR spectroscopy is commonly used for accurate molecular identification[1].Conventional IR analysis involves bulk samples,providing averaged information of the entire sample.The spatially-resolved investigation of heterogeneous sample properties is constrained by the micrometer-level spatial resolution of optical IR microscopy.

关键词： spatially hence rotation