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Oxime ester as bifunctional reagent for the alkylamination of alkynes via C-centered radical addition and N-centered radical migration
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作者 Keyuan Zhang Min Wang +3 位作者 Qi Jiang Bowu Dong Xin-Hua Duan Le Liu 《Science China Chemistry》 2026年第2期858-862,共5页
The radical addition/functional group migration strategy has emerged as a powerful tool for the difunctionalization of unsaturated hydrocarbons,yet the heteroatom-mediated functional group migration remains largely un... The radical addition/functional group migration strategy has emerged as a powerful tool for the difunctionalization of unsaturated hydrocarbons,yet the heteroatom-mediated functional group migration remains largely unexplored.Herein,we report an unprecedented radical difunctionalization of alkynes employing oxime esters as bifunctional reagents through a novel C-centered radical addition/N-centered radical translocation sequence.This innovative transformation paradigm enables efficient alkylamination of alkynes under mild photocatalytic redox conditions.Mechanistic investigations reveal a cascade sequence initiated by single-electron transfer from oxime derivatives,proceeding through radical addition,6-exo-trig cyclization,and subsequent imino group migration. 展开更多
关键词 bifunctional reagent alkylamination N-centered radical migration PHOTOREDOX tetrasubstituted alkenes
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Centralized Circumcentered-Reflection Method for Solving the Convex Feasibility Problem in Sparse Signal Recovery
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作者 Chunmei LI Bangjun CHEN Xuefeng DUAN 《Journal of Mathematical Research with Applications》 2026年第1期119-133,共15页
Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recov... Convex feasibility problems are widely used in image reconstruction, sparse signal recovery, and other areas. This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery. We first derive the projection formulas for a vector onto the feasible sets. The centralized circumcentered-reflection method is designed to solve the convex feasibility problem. Some numerical experiments demonstrate the feasibility and effectiveness of the proposed algorithm, showing superior performance compared to conventional alternating projection methods. 展开更多
关键词 convex feasibility problem centralized circumcentered-re ection method sparse signal recovery compressed sensing
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Emergent high-temperature superconductivity in two-dimensional XB_(2)(X=Si,Ge,Sn)monolayers via multicenter bonding
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作者 Wenyuan ZHANG Aitor BERGARA +1 位作者 Sheng WANG Guochun YANG 《Science China(Technological Sciences)》 2026年第2期220-228,共9页
Superconductivity in two-dimensional(2D)materials has attracted considerable attention due to their unique physical properties and potential for high-temperature operation.Boron-based 2D compounds are particularly pro... Superconductivity in two-dimensional(2D)materials has attracted considerable attention due to their unique physical properties and potential for high-temperature operation.Boron-based 2D compounds are particularly promising,thanks to their structural flexibility and the emergence of strong electron-phonon coupling(EPC)associated with light elements.While most previous studies have focused on stabilizing boron sheets through metal incorporation,we propose an alternative approach based on multicenter bonding enabled by group-IV non-metallic elements(Si,Ge,Sn).The resulting XB_(2)(X=Si,Ge,Sn)monolayers,which adopt a MgB_(2)-like monolayer configuration,are stabilized by a seven-center two-electron(7c-2e)bonding network between the X atoms and the boron honeycomb lattice.This bonding lowers the energy of the B-p_(z)orbitals and enhances lattice stability.The superconducting transition temperature(T_(c))increases significantly with the atomic number of X—from 4.7 K in SiB_(2)to 13.3 K in GeB_(2)and 24.9 K in SnB_(2)—driven by an increased carrier density near the Fermi level(E_(F))and softening of the high-frequency E_(2)phonon mode.Furthermore,we design a SnB_4 monolayer,in which a Sn layer is sandwiched between the two boron layers.This structure enriches in-plane phonon modes and strengthens EPC,yielding a T_(c)of 38 K,close to the McMillan limit.These findings highlight the critical role of multicenter bonding and targeted phonon engineering in enabling high-T_(c)2D boron-based superconductors. 展开更多
关键词 multicenter bonding first-principles calculations metallic covalent frameworks two-dimensional superconductivity
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Different approaches of laparoscopic anatomic hepatectomy of segment 7 for hepatocellular carcinoma:A multicenter study
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作者 Xing-Ru Wang Qi-Fan Zhang +6 位作者 Wei Cheng Xiao Liang Jun Cao Yong-Gang Wei Jian-Wei Li Hong-Guang Wang Chinese Research Group for Minimally Invasive Anatomical Liver Resection(The Workshop of Liver Future 《Hepatobiliary & Pancreatic Diseases International》 2026年第1期42-51,共10页
Background:Laparoscopic anatomic hepatectomy of segment 7(LAH-S7)is a challenging surgery.In this study we aimed to investigate surgical and oncological outcomes of various approaches of LAH-S7 in patients with hepato... Background:Laparoscopic anatomic hepatectomy of segment 7(LAH-S7)is a challenging surgery.In this study we aimed to investigate surgical and oncological outcomes of various approaches of LAH-S7 in patients with hepatocellular carcinoma(HCC).A particular focus was placed on identifying the Glissonean pedicle of segment 7(G7)and the intersegmental plane.Given the scarcity of comprehensive reviews or comparative studies on clinical outcomes,we also sought to analyze the experiences and advantages associated with different approaches in relation to the anatomic variations of G7.Methods:The clinical data of 124 patients who underwent LAH-S7 for HCC across seven tertiary referral medical centers in China were retrospectively analyzed.Three surgical approaches were categorized based on the procedures used for G7 identification:the indocyanine green(ICG)fluorescence positive staining approach(IFPA),the Glissonean approach(GA),and the hepatic vein-guided approach(HVGA).Subsequently,the postoperative short-term results and oncological outcomes of the three different approaches were compared.Results:The distribution of surgical approaches among the patients was as follows:IFPA in 16(12.9%),GA in 62(50.0%),and HVGA in 46(37.1%)patients.Complications were observed in 27(21.8%)patients.The 1-,3-,and 5-year overall survival(OS)rates were 99.1%,89.2%,and 84.7%,respectively.The 1-,3-,and 5-year recurrence-free survival(RFS)rates were 99.0%,84.7%,and 69.3%,respectively.The OS and RFS rates were comparable across the three approaches.Conclusions:Following a standardized surgical procedure,LAH-S7 is demonstrated to be safe and yields favorable oncological outcomes.Surgeons performing LAH-S7 should select the appropriate surgical approach based on the anatomical characteristics and variations of G7. 展开更多
关键词 Hepatocellular carcinoma Liver neoplasms HEPATECTOMY LAPAROSCOPY Indocyanine green Segment 7
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基于改进CenterNet算法的番茄叶片病害检测
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作者 李亚 蒋晨 +2 位作者 王海瑞 朱贵富 胡灿 《浙江大学学报(工学版)》 北大核心 2025年第11期2370-2378,共9页
为了解决在传统番茄叶片病害检测中出现的误检和漏检现象,提出基于改进CenterNet算法的番茄叶片病害检测模型.构建融合注意力机制的特征融合模块,增强模型的跨尺度特征融合能力.在骨干网络中加入多分支卷积模块RFB,扩大感受野,加强对目... 为了解决在传统番茄叶片病害检测中出现的误检和漏检现象,提出基于改进CenterNet算法的番茄叶片病害检测模型.构建融合注意力机制的特征融合模块,增强模型的跨尺度特征融合能力.在骨干网络中加入多分支卷积模块RFB,扩大感受野,加强对目标特征的提取能力.在骨干网络中引入金字塔卷积PyConv,通过计算不同尺度的感受野来强化多尺度特征的提取,减少信息损失.设计剪枝优化策略,减少引入模块给模型参数量和计算量带来的影响.试验结果显示,改进后模型的准确率、召回率、mAP_(50)和mAP_(50:95)达到96.3%、80.2%、91.4%和78.7%.利用提出的模型,能够有效地提升番茄叶片病害检测的准确性,模型具有良好的泛化性. 展开更多
关键词 番茄叶片病害 CenterNet 特征融合 金字塔卷积 多分支卷积
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New Chapter Between China and Switzerland in Cultural Exchange and Cooperation China Cultural Center Inaugurated in Bern
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作者 Cui Ke 《China & The World Cultural Exchange》 2025年第9期22-23,共2页
The official unveiling of China Cultural Center in Bern signifies a new era of cultural exchange between China and Switzerland.The Center will serve as a vital platform for dialogue between Chinese and Swiss cultures.
关键词 China cultural center Swiss Culture Chinese Culture COOPERATION China Cultural Center Bern Cultural Exchange
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基于改进CenterNet的输电线路异物目标检测 被引量:1
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作者 王明 宋公飞 +1 位作者 王瑞绅 张子梦 《计算机应用与软件》 北大核心 2025年第4期129-134,共6页
针对高压输电线路会存在异物影响线路正常运行,提出一种改进CenterNet的高压输电线路巡检异物的检测方法,对常见的输电线路异物小目标进行检测。该方法基于空洞卷积设计宽型残差模块,加宽残差模块的特征提取面,并且分别采用通道注意力... 针对高压输电线路会存在异物影响线路正常运行,提出一种改进CenterNet的高压输电线路巡检异物的检测方法,对常见的输电线路异物小目标进行检测。该方法基于空洞卷积设计宽型残差模块,加宽残差模块的特征提取面,并且分别采用通道注意力机制与空间注意力机制对特征信息进行二次处理,优化检测精度。实验结果显示,改进后的平均精度从88.59%提升到93.09%,整体提升了4.5百分点。 展开更多
关键词 深度学习 目标检测 CenterNet 输电线路 残差网络
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Prevalence of Helicobacter pylori infection in Chinese military personnel:A cross-sectional,multicenter-based study 被引量:1
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作者 Han-Chen Min Chun-Yan Zhang +9 位作者 Fang-Yu Wang Xiao-Hui Yu Shan-Hong Tang Hong-Wu Zhu Ya-Gang Zhao Ji-Luo Liu Jian Wang Jing-Han Guo Xiao-Mei Zhang Yun-Sheng Yang 《World Journal of Gastroenterology》 SCIE CAS 2025年第3期42-49,共8页
BACKGROUND Helicobacter pylori(H.pylori)infection is a prevalent disease encountered in military internal medicine and recognized as the main cause of dyspepsia,gastritis,and peptic ulcer,which are common diseases in ... BACKGROUND Helicobacter pylori(H.pylori)infection is a prevalent disease encountered in military internal medicine and recognized as the main cause of dyspepsia,gastritis,and peptic ulcer,which are common diseases in military personnel.Current guidelines in China state all patients with evidence of active infection with H.pylori are offered treatment.However,the prevalence of H.pylori infection and its regional distribution in the military population remain unclear,which hinders effective prevention and treatment strategies.Understanding the prevalence of H.pylori infection in the military population will aid in the development of customized strategies to better manage this infectious disease.AIM To investigate the prevalence of H.pylori infection in the Chinese military population in different geographic areas.METHODS This multicenter,retrospective study included 22421 individuals from five tertiary hospitals located in north,east,southwest,and northwest cities of China.H.pylori infection was identified using the urea breath test,which had been performed between January 2020 and December 2021.RESULTS Of the 22421 military service members,7416(33.1%)were urea breath test-positive.The highest prevalence of H.pylori was in the 30-39 years age group for military personnel,with an infection rate of 34.9%.The majority of infected subjects were younger than 40-years-old,accounting for 70.4%of the infected population.The individuals serviced in Lanzhou and Chengdu showed a higher infection prevalence than those in Beijing,Nanjing,and Guangzhou,with prevalence rates of 44.3%,37.9%,29.0%,31.1%,and 32.3%,respectively.CONCLUSION H.pylori infection remains a common infectious disease among military personnel in China and has a relatively high prevalence rate in northwest China. 展开更多
关键词 Helicobacter pylori PREVALENCE Military personnel Urea breath test Multicenter study
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Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders
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作者 Victor V.Chizhikov Igor Y.Iskusnykh 《Neural Regeneration Research》 SCIE CAS 2025年第4期1079-1080,共2页
Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,... Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical neuroepithelium.One such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in mice.The cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)proteins.The cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022). 展开更多
关键词 EPITHELIUM FIGURE CENTER
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A narrow-band blue emitting phosphor by co-doping Bi^(3+)and alkali metal ions(Li^(+),Na^(+)and K^(+))with dual luminescence center 被引量:1
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作者 Lang Ruan Zeyun Zhou +5 位作者 Yi Hu Ruifeng Peng Xiaoyan Chen Ming Cheng Zhi Zhou Mao Xia 《Journal of Rare Earths》 2025年第3期543-551,I0005,共10页
The technology of solid-state lighting has developed for decades in various industries.Phosphor,as an element part,determines the application domain of lighting products.For instance,blue and redemitting phosphors are... The technology of solid-state lighting has developed for decades in various industries.Phosphor,as an element part,determines the application domain of lighting products.For instance,blue and redemitting phosphors are required in the process of plant supplementing light,arrow-band emitting phosphors are applied to backlight displays,etc.In this work,a Bi^(3+)-activated blue phosphor was obtained in a symmetrical and co mpact crystal structure of Gd3Sb07(GSO).Then,the co-doping strategy of alkali metal ions(Li^(+),Na^(+),and K^(+))was used to optimize the performance.The result shows that the photoluminescence intensity is increased by 2.1 times and 1.3 times respectively by introducing Li~+and K^(+)ions.Not only that,it also achieves narrow-band emitting with the full width of half-maximum(FWHM)reaching 42 nm through Na^(+)doping,and its excitation peak position also shifts from 322 to 375 nm,which can be well excited by near-ultraviolet(NUV)light emitting diode(LED)chips(365 nm).Meanwhile,the electroluminescence spectrum of GSO:0.6 mol%Bi^(3+),3 wt%Na^(+)matches up to 93.39%of the blue part of the absorption spectrum of chlorophyll a.In summary,the Bi^(3+)-activated blue phosphor reported in this work can synchronously meet the requirements of plant light replenishment and field emission displays. 展开更多
关键词 Bismuth ion Alkali metal ion Narrow-band blue emitting Dual luminescent centers Rare earths
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The Birth on a Scarred Uterus at the Reference Health Center (csref) of Kolondiéba: Socio-Epidemiological and Maternel-Fetal Prognosis Aspect
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作者 Siaka Konaté Kélétigui Samuel Dembélé +6 位作者 Moussa Samaké Yacouba Dembélé Magacha Goita Mamoutou Diarra Souleymane Benké Dembélé Bakary Tientigui Dembélé Adégné Pierre Togo 《Surgical Science》 2025年第1期26-33,共8页
Introduction: Childbirth on a scarred uterus is a major issue for health centers, especially peripheral, due to the major obstetric risks it presents. The objectives were to evaluate the frequency, route of delivery a... Introduction: Childbirth on a scarred uterus is a major issue for health centers, especially peripheral, due to the major obstetric risks it presents. The objectives were to evaluate the frequency, route of delivery and maternal-fetal prognosis of this type of delivery at csref of Kolondiéba. Materials and Methods: This was a retrospective cross-sectional study for one year (1 January 2023-31 December 2023). All patients admitted to the maternity ward of the center with at least one uterine scar and treated in the center were included. We extracted data from partograms, OR records, birth records and obstetric records. Input was done on Excel 2010 and analysis on SPSS.23. Results: The frequency of scarring uterus was 16.8% (217/1285 births). The average age was 27. Pauciparous were most represented (59%). Patients were received from community health centers (44.7%). Prenatal consultation sessions (1 - 3 sessions) were performed at (64.9%). Uterine scars were obstetric in (99%). The cesarean section was performed immediately in (59.4%), it was prophylactic in 17%. The uterine test was attempted in (25.34%) with (69%) success. We recorded 3.6% uterine ruptures, 8.7% postoperative complications, 5.5% stillbirths and one maternal death (0.46%). Conclusion: Births on a scarred uterus are frequent and associated with a high rate of complications. 展开更多
关键词 Uterus Scar Delivery Kolondiéba Reference Health Center
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Analysis of the Application Effect of Community Health Center Nursing Models in Elderly Health Examinations
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作者 Qingrong Meng 《Journal of Clinical and Nursing Research》 2025年第11期54-60,共7页
Objective: To explore the application effect of optimizing the nursing model in community health centers for elderly health examinations, providing a reference for enhancing the management level of elderly health at t... Objective: To explore the application effect of optimizing the nursing model in community health centers for elderly health examinations, providing a reference for enhancing the management level of elderly health at the grassroots level. Methods: A total of 300 elderly individuals who underwent health examinations at our center from January 2024 to December 2024 were selected as the study subjects. They were randomly divided into a control group and an observation group, with 150 cases in each group. The control group underwent the conventional health examination nursing process, while the observation group adopted an optimized community nursing model, which included stratified education and appointment scheduling before the examination, full-time accompaniment and safety care during the examination, and the establishment of electronic medical records and continuous follow-up after the examination. Differences in health management awareness rates and satisfaction with health examination services between the two groups of elderly individuals were compared. Results: The health management awareness rate in the observation group was 94.67%, significantly higher than that in the control group (78.00%;p < 0.001). The satisfaction rate with health examination services in the observation group was 96.00%, also significantly higher than that in the control group (82.00%;p < 0.001). Conclusion: The optimized community nursing model can effectively enhance the health awareness level and service satisfaction of elderly individuals during health examinations, demonstrating strong practicality and promotion value. It contributes to achieving continuity and precision in grassroots elderly health management. 展开更多
关键词 Community health center Nursing model Elderly health examination Health management Service satisfaction
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The Role of Endoscope Diagnosis and Treatment Center Traceability System in Quality Control of Endoscope Cleaning
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作者 Na Zhao Fengjuan Wang 《Journal of Clinical and Nursing Research》 2025年第9期271-275,共5页
As the cornerstone of sterile instrument maintenance in endoscopy centers,the quality of endoscope cleaning directly impacts hospital infection control effectiveness.The traceability system for endoscopy centers utili... As the cornerstone of sterile instrument maintenance in endoscopy centers,the quality of endoscope cleaning directly impacts hospital infection control effectiveness.The traceability system for endoscopy centers utilizes digital means to document the entire cleaning process,enabling real-time monitoring and precise quality control.This paper analyzes current quality control practices in endoscope cleaning and addresses existing challenges.It explores how traceability systems standardize procedures,enhance monitoring,and improve management efficiency.The study proposes optimization strategies for traceability system implementation,clarifying its core value in endoscope cleaning quality control.These findings provide theoretical foundations and practical guidance for hospitals to refine management of endoscopy centers,ensure diagnostic safety,and reduce infection risks,ultimately advancing endoscope cleaning quality control toward standardized and informatized development. 展开更多
关键词 Endoscopic diagnosis and treatment center Traceability system Endoscope cleaning Quality control Hospital infection prevention and control
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The Effect of Occupational Protection Training on Disinfection Supply Center Personnel on Reducing the Risk of Nosocomial Infection
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作者 Fengjuan Wang Na Zhao 《Journal of Clinical and Nursing Research》 2025年第9期304-308,共5页
As the core department in medical institutions responsible for cleaning,disinfecting,sterilizing,and supplying reusable medical devices,instruments,and items,the quality of work in the disinfection supply center direc... As the core department in medical institutions responsible for cleaning,disinfecting,sterilizing,and supplying reusable medical devices,instruments,and items,the quality of work in the disinfection supply center directly impacts medical safety and infection control effectiveness.Professional protective training for personnel is crucial to ensure operational quality in this department.Systematic training enhances staff awareness of occupational exposure risks,standardizes protective measures in procedures,reduces cross-infection risks caused by improper operations,and ultimately lowers infection transmission risks.This paper analyzes the core content,implementation approaches,and practical role of professional protective training for disinfection supply center personnel in infection control.It aims to clarify the significant value of such training,providing references for medical institutions to optimize disinfection center management and strengthen infection control systems,thereby contributing to improved overall medical safety standards. 展开更多
关键词 Disinfection supply center Occupational protection training Hospital infection risk Medical safety Operation specification
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AN INEXACT SYMMETRIC PROXIMAL ADMM WITH CONVEX COMBINATION PROXIMAL CENTERS FOR SEPARABLE CONVEX PROGRAMMING
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作者 Xianke TANG Jinbao JIAN +1 位作者 Jianghua YIN Xianzhen JIANG 《Acta Mathematica Scientia》 2025年第4期1701-1722,共22页
In this paper,we develop an inexact symmetric proximal alternating direction method of multipliers(ISPADMM)with two convex combinations(ISPADMM-tcc)for solving two-block separable convex optimization problems with lin... In this paper,we develop an inexact symmetric proximal alternating direction method of multipliers(ISPADMM)with two convex combinations(ISPADMM-tcc)for solving two-block separable convex optimization problems with linear equality constraints.Specifically,the convex combination technique is incorporated into the proximal centers of both subproblems.We then approximately solve these two subproblems based on relative error criteria.The global convergence,and O(1/N)ergodic sublinear convergence rate measured by the function value residual and constraint violation are established under some mild conditions,where N denotes the number of iterations.Finally,numerical experiments on solving the l1-regularized analysis sparse recovery and the elastic net regularization regression problems illustrate the feasibility and effectiveness of the proposed method. 展开更多
关键词 sparable convex optimization convex combination proximal centers relative error criterion ISPADMM ergodic sublinear convergence rate
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Prognostic Factors for Operated Traumatic Brain Injury at the Yaounde Emergency Center
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作者 Ernestine Renée Bikono Atangana Alain Jibia +5 位作者 Serge Rawlings Ngouatna Reid Achu Darius Kenzo Temgoua Herve Mfouapon Ewane Casimir Fankem Vincent de Paul Djientcheu 《Open Journal of Modern Neurosurgery》 2025年第1期88-95,共8页
Introduction: Head injuries constitute a public health problem in Cameroon and everywhere else in the world. They represent 23% of admissions to the Yaounde emergency center (CURY), which is a center exclusively dedic... Introduction: Head injuries constitute a public health problem in Cameroon and everywhere else in the world. They represent 23% of admissions to the Yaounde emergency center (CURY), which is a center exclusively dedicated, since 2014, to emergency care in Yaounde. In the management of trauma brain injuries at CURY, several are operated on. However, to date, no evaluation of these operated patients has yet been made. Goals: The objective of this study was to highlight the prognostic factors in patients operated for TBI at CURY. Methodology: We conducted a descriptive study whose data collection was done retrospectively over 2 years (01 January 2021 to 31 December 2022) at CURY. Data was collected from the registers of operative reports. Results: We enrolled 105 medical reports of patients who were victims of TBI operated on. The male gender predominated with a sex ratio of 3/1. The average age of the patients was 37.5 ± 18.83 years. Public road accidents were the leading cause of TBI in 75.2% of cases. The means of transport of the victims were mostly non-medical 97.1%. 45.7% of patients were admitted in less than 6 hours following injury. The initial clinical evaluation found 45.8% of patients with a Glasgow Coma Score (GCS) between [14, 15], and 13.2% of patients had a GCS 8. The indications for surgery were extradural hematoma (30%), followed by acute subdural hematoma (24%). The major complication was postoperative infection (25%). The mortality rate of the series was 7.9%. Poor prognostic factors were the depth of the coma on admission, advanced age and postoperative complications. Conclusion: The results of this study suggest that most patients operated on for TBI at CURY had a favorable outcome. The poor prognostic factors were the depth of the coma on admission, advanced age, postoperative complications and comorbidities. 展开更多
关键词 Operated TBI PROGNOSIS Yaounde Emergency Center
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Engineering d-band center of Mn to strengthen Mn-O bonding for long cycle life zinc-ion battery
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作者 Xinyu Yu Ziyi Zhang +3 位作者 Xinya Chen Lixia Bao Jiong Peng Xin Li 《Journal of Materials Science & Technology》 2025年第26期203-212,共10页
MnO_(2)has emerged as one of the favored cathode materials for aqueous zinc ion batteries(AZIBs)due to its high theoretical capacity and abundant crystalline structures.However,MnO_(2)cathode generally suffers from po... MnO_(2)has emerged as one of the favored cathode materials for aqueous zinc ion batteries(AZIBs)due to its high theoretical capacity and abundant crystalline structures.However,MnO_(2)cathode generally suffers from poor electrical conductivity and rapid capacity degradation due to unavoidable manganese dissolution during cycling,limiting their further utilization.In this study,we modify the d-band center of Mn by introducing non-precious metal Bi atoms into the MnO_(2)system,thereby strengthening the Mn-O bonding to inhibit manganese dissolution.Theoretical calculations reveal that the d-band center of Mn in Bi-MnO_(2)shifts upward,promoting electron transfer from O 2p orbitals to Mn-O bonding orbitals.This enhances the Mn-O bond strength,stabilizing Mn atoms in the crystal lattice and reducing manganese solvation loss.As a result,the conductivity and cyclic stability of Bi-MnO_(2)are significantly improved.The results demonstrate that Bi-MnO_(2)exhibits outstanding electrochemical properties,with a capacity of 392.3 mAh g^(-1)after 100 cycles at 0.2 A g^(-1)and a capacity retention of 83.25%after 5000 cycles at 1.0 A g^(-1).This study presents a new approach to address the manganese dissolution issue,which could further advance the application of d-band center theory in MnO_(2)materials. 展开更多
关键词 DOPING D-band center MnO_(2)cathode Aqueous zinc ion batteries
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Treatment options in patients with pancreatic cancer:A 10-year multicenter epidemiological investigation in China
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作者 Wan-Yi Sun Shui-Sheng Zhang +7 位作者 Shao-Kai Zhang Ren-Yi Qin Bin Zhou Jun Liu Sheng-Ping Li Ru-Fu Chen Cheng-Feng Wang Jin-Hu Fan 《World Journal of Gastrointestinal Oncology》 2025年第8期95-108,共14页
BACKGROUND The survival rate of pancreatic cancer is low,and there is a lack of effective treatment.AIM To explore the epidemiological characteristics of patients with pancreatic cancer in China and compare multiple c... BACKGROUND The survival rate of pancreatic cancer is low,and there is a lack of effective treatment.AIM To explore the epidemiological characteristics of patients with pancreatic cancer in China and compare multiple chemotherapy regimens at different stages.METHODS This was a retrospective study conducted from 2005 to 2014,involving six cancer hospitals and eight general hospitals across seven geographical regions of China(East,South,North,Central,Southwest,Northwest,and Northeast).Stratified sampling was used based on the population distribution of each region.Efficacy assessments were conducted by Cox proportional hazards regression models.When assessing the effectiveness of various chemotherapy regimens,traditional drugs such as gemcitabine used as monotherapy served as the reference.RESULTS A total of 3256 patients were included.The median follow-up time was 407 days,and the median overall survival was 183 days.At diagnosis,56%of patients were already in stage IV.Chemotherapy was administered to 39.73%of patients.In the adjuvant therapy phase,gemcitabine+fluorouracil was superior to gemcitabine monotherapy[hazard ratio(HR)=0.35,95%confidence interval(CI):0.14-0.89].In fluorouracil-based regimens,other combination regimens did not show effectiveness relative to monotherapy.For first-line treatment in patients with advanced disease,tegafur alone(HR=0.20,95%CI:0.06-0.66),gemcitabine plus cisplatin(HR=0.16,95%CI:0.04-0.70),and tegafur,gemcitabine plus platinum-based agents(HR=0.32,95%CI:0.11-0.91)were associated with a lower risk of death compared to gemcitabine alone.In second-line treatment,there were no significant differences in efficacy among various drugs,but FOLFIRINOX(irinotecan+oxaliplatin+leucovorin+5-fluorouracil)had an outstanding point estimate(HR=0.10,95%CI:0.01-1.27).CONCLUSION In China,pancreatic cancer is often diagnosed at advanced stages,emphasizing the need for early diagnosis and treatment.Combined therapies in adjuvant and first-line settings may reduce the risk of death compared with monotherapy,and FOLFIRINOX might offer more significant benefits in second-line treatment. 展开更多
关键词 Pancreatic cancer EPIDEMIOLOGY CHEMOTHERAPY Risk factors Multicenter retrospective study
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Comparison of asymmetric offset versus pupil centered ablation in refractive surgery
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作者 Hassan Hashemi Mojgan Pakbin +2 位作者 Alireza Hashemi Mohammadreza Aghamirsalim Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 2025年第8期1537-1543,共7页
AIM:To compare the visual and optical outcomes following femtosecond laser in situ keratomileusis(FS-LASIK)using an aberration neutral profile with asymmetric offset(AO)and pupil center(PC)treatments.METHODS:In this r... AIM:To compare the visual and optical outcomes following femtosecond laser in situ keratomileusis(FS-LASIK)using an aberration neutral profile with asymmetric offset(AO)and pupil center(PC)treatments.METHODS:In this randomized double-blind clinical trial study,48(24 cases)and 38 eyes(19 cases)underwent myopic astigmatism and hyperopic astigmatism LASIK.One eye of each individual was randomly assigned to AO centration and the fellow eye underwent the PC-centered method.The clinical outcomes including uncorrected visual acuity(UCVA),best-corrected visual acuity(BCVA),safety and efficacy indexes,subjective spherical equivalent(SE)and corneal high-order aberrations(HOAs)were measured at baseline and 6mo postoperatively.RESULTS:In the myopic group,the mean preoperative SE and astigmatism were-4.12±0.87(-2.88 to-6.00)diopter(D)and-0.88±0.79(0 to-2.75)D,respectively.In the hyperopic group,the mean preoperative SE and astigmatism were 0.93±0.59(-0.25 to 2.25)D and-0.73±1.00(0 to-4.25)D,respectively.At 6mo postoperatively,the safety and efficacy indexes were similar for centration in myopic and hyperopic LASIK groups.In the myopic group,significant changes were found in horizontal trefoil(P=0.041)and oblique trefoil(P=0.031)in favor of AO centration treatment.CONCLUSION:Femtosecond-LASIK is a safe and efficacious procedure for treatment of myopic and hyperopic astigmatism.AO-centered and PC-centered approaches provide similar visual and refractive outcomes.Myopic astigmatism LASIK with AO centration leads to slightly better corneal aberration outcomes. 展开更多
关键词 femtosecond laser in situ keratomileusis asymmetric offset pupil center
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Regulating the valence and size of the active center of Co/Al_(2)O_(3)catalyst improved the performance and selectivity of NH_(3)-SCO
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作者 Shengyi Wu Jiaxin Li +5 位作者 Junjun Qiu Chunxue Wang Fei Wang Zhao Li Ping Ning Kai Li 《Journal of Environmental Sciences》 2025年第4期188-201,共14页
To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(... To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(2)reduction pretreatment.The NH_(3)-SCO activity of the adjusted 2Co/Al_(2)O_(3)catalyst was substantially improved,outperforming other catalysts with higher Co-loading.Fresh Co/Al_(2)O_(3)catalysts exhibited multitemperature reduction processes,enabling the control of the valence state of the Co-active centers by adjusting the reduction temperature.Changes in the state of the Co-active centers also led to differences in redox capacity of the catalysts,resulting in different reaction mechanisms for NH_(3)-SCO.However,in situ diffuse reflectance infrared Fourier transform spectra revealed that an excessive O_(2)activation capacity caused overoxidation of NH_(3)to NO and NO_(2).The NH_(3)-SCO activity of the 2Co/Al_(2)O_(3)catalyst with low redox capacity was successfully increased while controlling and optimizing the N_(2)selectivity by modulating the active centers via H_(2)pretreatment,which is a universalmethod used for enhancing the redox properties of catalysts.Thus,this method has great potential for application in the design of inexpensive and highly active catalysts. 展开更多
关键词 NH_(3)-SCO Active center O_(2)activation capacity Reaction mechanism H_(2)pretreatment
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