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A Privacy Preservation Method for Attributed Social Network Based on Negative Representation of Information
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作者 Hao Jiang Yuerong Liao +2 位作者 Dongdong Zhao Wenjian Luo Xingyi Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1045-1075,共31页
Due to the presence of a large amount of personal sensitive information in social networks,privacy preservation issues in social networks have attracted the attention of many scholars.Inspired by the self-nonself disc... Due to the presence of a large amount of personal sensitive information in social networks,privacy preservation issues in social networks have attracted the attention of many scholars.Inspired by the self-nonself discrimination paradigmin the biological immune system,the negative representation of information indicates features such as simplicity and efficiency,which is very suitable for preserving social network privacy.Therefore,we suggest a method to preserve the topology privacy and node attribute privacy of attribute social networks,called AttNetNRI.Specifically,a negative survey-based method is developed to disturb the relationship between nodes in the social network so that the topology structure can be kept private.Moreover,a negative database-based method is proposed to hide node attributes,so that the privacy of node attributes can be preserved while supporting the similarity estimation between different node attributes,which is crucial to the analysis of social networks.To evaluate the performance of the AttNetNRI,empirical studies have been conducted on various attribute social networks and compared with several state-of-the-art methods tailored to preserve the privacy of social networks.The experimental results show the superiority of the developed method in preserving the privacy of attribute social networks and demonstrate the effectiveness of the topology disturbing and attribute hiding parts.The experimental results show the superiority of the developed methods in preserving the privacy of attribute social networks and demonstrate the effectiveness of the topological interference and attribute-hiding components. 展开更多
关键词 Attributed social network topology privacy node attribute privacy negative representation of information negative survey negative database
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The characteristics of negative corona discharge and radio interference at different altitudes based on coaxial wire-cylinder gap
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作者 何旺龄 魏宏宇 +6 位作者 张胤禄 刘永聪 刘云鹏 万保权 周阳 王延召 干喆渊 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期77-85,共9页
The corona discharge from transmission lines in high-altitude areas is more severe than at lower altitudes. The radio interference caused thereby is a key factor to be considered when designing transmission lines. To ... The corona discharge from transmission lines in high-altitude areas is more severe than at lower altitudes. The radio interference caused thereby is a key factor to be considered when designing transmission lines. To study the influence of altitude on negative corona characteristics, an experimental platform comprising a movable small corona cage was established: experiments were conducted at four altitudes in the range of 1120-4320 m, and data on the corona current pulse and radio interference level of 0.8-mm diameter fine copper wire under different negative voltages were collected. The experimental results show that the average amplitude, repetition frequency and average current of the corona current pulse increase with increasing altitude. The dispersion of pulse amplitude increases with increase in altitude, while the randomness of the pulse interval decreases continuously. Taking the average current as an intermediate variable,the relationship between radio interference level and altitude is obtained. The result of this research has some significance for understanding the corona discharge characteristics of ultra-highvoltage lines. 展开更多
关键词 ALTITUDE negative corona corona current pulse radio interference level
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Scheme of negative acoustic radiation force based on a multiple-layered spherical structure
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作者 宫门阳 徐鑫 +3 位作者 乔玉配 刘杰惠 何爱军 刘晓宙 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期477-487,共11页
Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has... Acoustic radiation force(ARF), as an important particle manipulation method, has been extensively studied in recent years. With the introduction of the concept of “acoustic tweezers”, negative acoustic radiation has become a research hotspot. In this paper, a scheme of realizing negative ARF based on the multiple-layered spherical structure design is proposed. The specific structure and design idea are presented. Detailed theoretical calculation analysis is carried out.Numerical simulations have been performed to verify the correctness of this prediction. The conjecture that the suppression of backscattering can achieve negative ARF is verified concretely, which greatly expands the application prospect and design ideas of the ARF. This work has laid a theoretical foundation for realizing precise control of the structure. 展开更多
关键词 acoustic tweezers negative acoustic radiation force particle manipulation
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The Negative Thermal Expansion Property of NdMnO_(3) Based on Pores Effect and Phase Transition
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作者 李玉成 张扬 +2 位作者 ZHANG Muqun DUAN Rong LIU Xiteng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期39-43,共5页
A novel negative thermal expansion(NTE) material NdMnO_(3) was synthesized by solid-state method at 1 523 K. The crystal structure, phase transition, pores effect and negative expansion properties of NdMnO_(3) were in... A novel negative thermal expansion(NTE) material NdMnO_(3) was synthesized by solid-state method at 1 523 K. The crystal structure, phase transition, pores effect and negative expansion properties of NdMnO_(3) were investigated by variable temperature X-ray diffraction(XRD), scanning electron microscope(SEM) and variable temperature Raman spectra. The compound exhibits NTE properties in the orderly O' phase crystal structure. When the temperature is from 293 to 759 K, the ceramic NdMnO_(3) shows negative thermal expansion of-4.7×10^(-6)/K. As temperature increases, the ceramic NdMnO_(3) presents NTE property range from 759 to 1 007 K. The average linear expansion coefficient is-18.88×10^(-6)/K. The physical mechanism of NTE is discussed and clarified through experiments. 展开更多
关键词 negative thermal expansion NdMnO_(3) pores effect phase transition
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Spin logic devices based on negative differential resistance -enhanced anomalous Hall effect
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作者 Hongming Mou Ziyao Lu +2 位作者 Yuchen Pu Zhaochu Luo Xiaozhong Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1437-1448,共12页
Owing to rapid developments in spintronics,spin-based logic devices have emerged as promising tools for next-generation computing technologies.This paper provides a comprehensive review of recent advancements in spin ... Owing to rapid developments in spintronics,spin-based logic devices have emerged as promising tools for next-generation computing technologies.This paper provides a comprehensive review of recent advancements in spin logic devices,particularly focusing on fundamental device concepts rooted in nanomagnets,magnetoresistive random access memory,spin–orbit torques,electric-field modu-lation,and magnetic domain walls.The operation principles of these devices are comprehensively analyzed,and recent progress in spin logic devices based on negative differential resistance-enhanced anomalous Hall effect is summarized.These devices exhibit reconfigur-able logic capabilities and integrate nonvolatile data storage and computing functionalities.For current-driven spin logic devices,negative differential resistance elements are employed to nonlinearly enhance anomalous Hall effect signals from magnetic bits,enabling reconfig-urable Boolean logic operations.Besides,voltage-driven spin logic devices employ another type of negative differential resistance ele-ment to achieve logic functionalities with excellent cascading ability.By cascading several elementary logic gates,the logic circuit of a full adder can be obtained,and the potential of voltage-driven spin logic devices for implementing complex logic functions can be veri-fied.This review contributes to the understanding of the evolving landscape of spin logic devices and underscores the promising pro-spects they offer for the future of emerging computing schemes. 展开更多
关键词 spin logic spin–orbit torque negative differential resistance full-adder
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Topology Optimization of Metamaterial Microstructures for Negative Poisson’s Ratio under Large Deformation Using a Gradient-Free Method
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作者 Weida Wu Yiqiang Wang +1 位作者 Zhonghao Gao Pai Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2001-2026,共26页
Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching... Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching,NPR metamaterials designed under small strain assumption may experience a rapid degradation in NPR performance.To address this issue,this study aims to design metamaterials maintaining a targeted NPR under large deformation by taking advantage of the geometry nonlinearity mechanism.A representative periodic unit cell is modeled considering geometry nonlinearity,and its topology is designed using a gradient-free method.The unit cell microstructural topologies are described with the material-field series-expansion(MFSE)method.The MFSE method assumes spatial correlation of the material distribution,which greatly reduces the number of required design variables.To conveniently design metamaterials with desired NPR under large deformation,we propose a two-stage gradient-free metamaterial topology optimization method,which fully takes advantage of the dimension reduction benefits of the MFSE method and the Kriging surrogate model technique.Initially,we use homogenization to find a preliminary NPR design under a small deformation assumption.In the second stage,we begin with this preliminary design and minimize deviations in NPR from a targeted value under large deformation.Using this strategy and solution technique,we successfully obtain a group of NPR metamaterials that can sustain different desired NPRs in the range of[−0.8,−0.1]under uniaxial stretching up to 20% strain.Furthermore,typical microstructure designs are fabricated and tested through experiments.The experimental results show good consistency with our numerical results,demonstrating the effectiveness of the present gradientfree NPR metamaterial design strategy. 展开更多
关键词 Topology optimization microstructural design negative Poisson’s ratio large deformation
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Association of serum interleukin-6 with negative symptoms in stable early-onset schizophrenia
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作者 Peng Chen Hai-Dong Yang +10 位作者 Jun-Jie Wang Zhen-Hua Zhu Hui-Min Zhao Xu-Yuan Yin Yuan Cai Hong-LiangZhu Jia-Lin Fu Xin-Zhu Zhang Wen-Xi Sun Li Hui Xiao-Bin Zhang 《World Journal of Psychiatry》 SCIE 2024年第6期794-803,共10页
BACKGROUND Accumulating evidence suggests that the inflammatory cytokine interleukin-6(IL-6)contributes to the pathophysiology of psychiatric disorders.However,there was no study concerning the relationship between IL... BACKGROUND Accumulating evidence suggests that the inflammatory cytokine interleukin-6(IL-6)contributes to the pathophysiology of psychiatric disorders.However,there was no study concerning the relationship between IL-6 concentrations and clinical features in the chronic phase of early-onset schizophrenia(EOS).AIM To investigate the relationship between serum IL-6 concentration and the clinical features of EOS.METHODS We measured serum IL-6 Levels from 74 patients with chronic schizophrenia,including 33 with age at onset<21 years(EOS group)and 41 with onset≥21 years in[adult-onset schizophrenia(AOS)group],and from 41 healthy controls.Symptom severities were evaluated using the Positive and Negative Syndrome Scale(PANSS).RESULTS Serum IL-6 concentrations were higher in both EOS and AOS groups than healthy controls(F=22.32,P<0.01),but did not differ significantly between EOS and AOS groups(P>0.05)after controlling for age,body mass index,and other covariates.Negative symptom scores were higher in the EOS group than the AOS group(F=6.199,P=0.015).Serum IL-6 concentrations in the EOS group were negatively correlated with both total PANSS-negative symptom score(r=-0.389,P=0.032)and avolition/asociality subscore(r=-0.387,P=0.026).CONCLUSION Patients with EOS may have more severe negative symptoms than those with adult-onset schizophrenia during the chronic phase of the illness.IL-6 signaling may regulate negative symptoms and its avolition/asociality subsymptoms among the early-onset chronic schizophrenic patients. 展开更多
关键词 Early-onset schizophrenia Interleukin 6 negative symptoms Avolition Asociality
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Experimental results of a magnetic field modification to the radio frequency driver of a negative ion source
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作者 谢俊炜 谢亚红 +6 位作者 韦江龙 梁立振 彭旭峰 杨宇雯 顾玉明 胡纯栋 谢远来 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期162-167,共6页
A magnetic field produced by a current flowing through the plasma grid(PG) is one of the solutions to reduce the collisional loss of negative ions in a negative ion source, which reduces the electron temperature in fr... A magnetic field produced by a current flowing through the plasma grid(PG) is one of the solutions to reduce the collisional loss of negative ions in a negative ion source, which reduces the electron temperature in front of the PG. However, the magnetic field diffused into the driver has some influence on the plasma outflowing. In order to investigate the effect of changing this magnetic field on the outflowing of plasma from the driver, a circular ring(absorber) of high permeability iron has been introduced at the driver exit, which can reduce the magnetic field around it and improve plasma outflowing. With the application of the absorber, the electron density is increased by about 35%, and the extraction current measured from the extraction grid is increased from 1.02 A to 1.29 A. The results of the extraction experiment with cesium injection show that both the extraction grid(EG) current and H-current are increased when the absorber is introduced. 展开更多
关键词 neutral beam injection negative ion source magnetic filter radio frequency ion source
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Characteristics and triggering mechanisms of early negative Indian Ocean Dipole
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作者 Yue Fang Shuangwen Sun +2 位作者 Yongcan Zu Jianhu Wang Lin Feng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期59-65,共7页
Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in... Negative Indian Ocean Dipole(nIOD)can exert great impacts on global climate and can also strongly influence the climate in China.Early nIOD is a major type of nIOD,which can induce more pronounced climate anomalies in summer than La Niña-related nIOD.However,the characteristics and triggering mechanisms of early nIOD are unclear.Our results based on reanalysis datasets indicate that the early nIOD and La Niña-related nIOD are the two major types of nIOD,and the former accounts for over one third of all the nIOD events in the past six decades.These two types of nIODs are similar in their intensities,but are different in their spatial patterns and seasonal cycles.The early nIOD,which develops in spring and peaks in summer,is one season earlier than the La Niña-related nIOD.The spatial pattern of the wind anomaly associated with early nIOD exhibits a winter monsoon-like pattern,with strong westerly anomalies in the equatorial Indian Ocean and eastly anomalies in the northern Indian Ocean.Opposite to the triggering mechanism of early positve IOD,the early nIOD is induced by delayed Indian summer monsoon onset.The results of this study are helpful for improving the prediction skill of IOD and its climate impacts. 展开更多
关键词 Indian Ocean Dipole(IOD) triggering mechanism Indian summer monsoon seasonal cycle negative IOD
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Effect of cardiac rehabilitation care after coronary intervention on cardiac function recovery and negative mood in patients with myocardial infarction
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作者 Ming Yang Yuan-Tao Huang +1 位作者 Xi-Wen Hu Chun-Ling Wu 《World Journal of Clinical Cases》 SCIE 2024年第1期59-67,共9页
BACKGROUND Cardiovascular disease,particularly myocardial infarction(MI)profound impact on patients'quality of life and places a substantial burden on the healthcare and economy systems.Developments in medical tec... BACKGROUND Cardiovascular disease,particularly myocardial infarction(MI)profound impact on patients'quality of life and places a substantial burden on the healthcare and economy systems.Developments in medical technology have led to the emer-gence of coronary intervention as an essential method for treating MI.AIM To assess the effects of cardiac rehabilitation care on cardiac function recovery and negative emotions in MI after coronary intervention.METHODS This study included a total of 180 patients with MI during the period from June 2022 to July 2023.Selected patients were divided into two groups:An observation group,which receiving cardiac rehabilitation care;a control group,which re-ceiving conventional care.By comparing multiple observation indicators such as cardiac function indicators,blood pressure,exercise tolerance,occurrence of adverse cardiac events,and negative emotion scores between the two groups of patients.All the data were analyzed and compared between two groups.RESULTS There were 44 males and 46 females in the observation group with an average age of 36.26±9.88 yr;there were 43 males and 47 females in the control group,with an average age of 40.87±10.5 yr.After receiving the appropriate postoperative nursing measures,the results of the observation group showed significant improvement in several indicators compared with the control group.Indicators of cardiac function,such as left ventricular end-diastolic internal diameter and left ventricular ejection fraction were significantly better in the observation group than in the control group(P<0.05).Exercise endurance assessment showed that the 6-minute walking test distance was significantly increased in the patients of the observation group(P<0.01).In addition,the incidence of adverse cardiac events was significantly lower in the observation group,and negative mood scores were significantly reduced(P<0.05).CONCLUSION Cardiac rehabilitation care after coronary intervention has a significant positive impact on functional recovery.This emphasizes the importance of cardiac rehabilitation care to improve patient recovery. 展开更多
关键词 Myocardial infarction Coronary artery intervention Cardiac rehabilitation Cardiac function recovery negative emotions
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Effects of psychological intervention on negative emotions and psychological resilience in breast cancer patients after radical mastectomy
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作者 Jing Wang Dong-Xue Kang +1 位作者 Ai-Jun Zhang Bing-Rui Li 《World Journal of Psychiatry》 SCIE 2024年第1期8-14,共7页
Breast cancer(BC)is the most common malignant tumor in women,and the treatment process not only results in physical pain but also significant psychological distress in patients.Psychological intervention(PI)has been r... Breast cancer(BC)is the most common malignant tumor in women,and the treatment process not only results in physical pain but also significant psychological distress in patients.Psychological intervention(PI)has been recognized as an important approach in treating postoperative psychological disorders in BC patients.It has been proven that PI has a significant therapeutic effect on postoperative psychological disorders,improving patients'negative emotions,enhancing their psychological resilience,and effectively enhancing their quality of life and treatment compliance. 展开更多
关键词 Breast cancer Psychological intervention negative emotions Psychological resilience Radical surgery
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Sepsis one-hour bundle management combined with psychological intervention on negative emotion and sleep quality in patients with sepsis
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作者 Ming Xia Guang-Yan Dong +2 位作者 Shi-Chao Zhu Huan-Min Xing Li-Ming Li 《World Journal of Psychiatry》 SCIE 2024年第2期266-275,共10页
BACKGROUND Sepsis is a serious infectious disease caused by various systemic inflammatory responses and is ultimately life-threatening.Patients usually experience depression and anxiety,which affect their sleep qualit... BACKGROUND Sepsis is a serious infectious disease caused by various systemic inflammatory responses and is ultimately life-threatening.Patients usually experience depression and anxiety,which affect their sleep quality and post-traumatic growth levels.AIM To investigate the effects of sepsis,a one-hour bundle(H1B)management was combined with psychological intervention in patients with sepsis.METHODS This retrospective analysis included 300 patients with sepsis who were admitted to Henan Provincial People’s Hospital between June 2022 and June 2023.According to different intervention methods,the participants were divided into a simple group(SG,n=150)and combined group(CG,n=150).H1B management was used in the SG and H1B management combined with psychological intervention was used in the CG.The changes of negative emotion,sleep quality and post-traumatic growth and prognosis were compared between the two groups before(T0)and after(T1)intervention.RESULTS After intervention(T1),the scores of the Hamilton Anxiety scale and Hamilton Depression scale in the CG were significantly lower than those in the SG(P<0.001).Sleep time,sleep quality,sleep efficiency,daytime dysfunction,sleep disturbance dimension score,and the total score in the CG were significantly lower than those in the SG(P<0.001).The appreciation of life,mental changes,relationship with others,personal strength dimension score,and total score of the CG were significantly higher than those of the SG(P<0.001).The scores for mental health,general health status,physiological function,emotional function,physical pain,social function,energy,and physiological function in the CG were significantly higher than those in the SG(P<0.001).The mechanical ventilation time,intensive care unit stay time,and 28-d mortality of the CG were significantly lower than those of the SG(P<0.05).CONCLUSION H1B management combined with psychological intervention can effectively alleviate the negative emotions of patients with sepsis and increase their quality of sleep and life. 展开更多
关键词 Cluster management Psychological intervention SEPSIS negative emotions Sleep quality Post-traumatic growth
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Personalized and continuous care intervention affects rehabilitation,living quality,and negative emotions of patients with breast cancer
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作者 Ling-Xia Kong Yan-Hong Zhao +1 位作者 Zhi-Lin Feng Ting-Ting Liu 《World Journal of Psychiatry》 SCIE 2024年第6期876-883,共8页
BACKGROUND Breast cancer is among the most common malignancies worldwide.With progress in treatment methods and levels,the overall survival period has been prolonged,and the demand for quality care has increased.AIM T... BACKGROUND Breast cancer is among the most common malignancies worldwide.With progress in treatment methods and levels,the overall survival period has been prolonged,and the demand for quality care has increased.AIM To investigate the effect of individualized and continuous care intervention in patients with breast cancer.METHODS Two hundred patients with breast cancer who received systemic therapy at The First Affiliated Hospital of Hebei North University(January 2021 to July 2023)were retrospectively selected as research participants.Among them,134 received routine care intervention(routing group)and 66 received personalized and continuous care(intervention group).Self-rating anxiety scale(SAS),self-rating depression scale(SDS),and Functional Assessment of Cancer Therapy-Breast(FACT-B)scores,including limb shoulder joint activity,complication rate,and care satisfaction,were compared between both groups after care.RESULTS SAS and SDS scores were lower in the intervention group than in the routing group at one and three months after care.The total FACT-B scores and five dimensions in the intervention group were higher than those in the routing group at three months of care.The range of motion of shoulder anteflexion,posterior extension,abduction,internal rotation,and external rotation in the intervention group was higher than that in the routing group one month after care.The incidence of postoperative complications was 18.18%lower in the intervention group than in the routing group(34.33%;P<0.05).Satisfaction with care was 90.91% higher in the intervention group than in the routing group(78.36%;P<0.05).CONCLUSION Personalized and continuous care can alleviate negative emotions in patients with breast cancer,quicken rehabilitation of limb function,decrease the incidence of complications,and improve living quality and care satisfaction. 展开更多
关键词 Breast cancer Personalized care Continuous care negative emotions Living quality Rehabilitation effect
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Interaction between catechol-O-methyltransferase Val/Met polymorphism and cognitive reserve for negative symptoms in schizophrenia
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作者 Wen-Peng Hou Xiang-Qin Qin +6 位作者 Wei-Wei Hou Yun-Yi Han Qi-Jing Bo Fang Dong Fu-Chun Zhou Xian-Bin Li Chuan-Yue Wang 《World Journal of Psychiatry》 SCIE 2024年第5期695-703,共9页
BACKGROUND Cognitive reserve(CR)and the catechol-O-methyltransferase(COMT)Val/Met polymorphism are reportedly linked to negative symptoms in schizophrenia.However,the regulatory effect of the COMT genotype on the rela... BACKGROUND Cognitive reserve(CR)and the catechol-O-methyltransferase(COMT)Val/Met polymorphism are reportedly linked to negative symptoms in schizophrenia.However,the regulatory effect of the COMT genotype on the relationship between CR and negative symptoms is still unexamined.AIM To investigate whether the relationship between CR and negative symptoms could be regulated by the COMT Val/Met polymorphism.METHODS In a cross-sectional study,54 clinically stable patients with schizophrenia underwent assessments for the COMT genotype,CR,and negative symptoms.CR was estimated using scores in the information and similarities subtests of a short form of the Chinese version of the Wechsler Adult Intelligence Scale.RESULTS COMT Met-carriers exhibited fewer negative symptoms than Val homozygotes.In the total sample,significant negative correlations were found between negative symptoms and information,similarities.Associations between information,similarities and negative symptoms were observed in Val homozygotes only,with information and similarities showing interaction effects with the COMT genotype in relation to negative symptoms(information,β=-0.282,95%CI:-0.552 to-0.011,P=0.042;similarities,β=-0.250,95%CI:-0.495 to-0.004,P=0.046).CONCLUSION This study provides initial evidence that the association between negative symptoms and CR is under the regulation of the COMT genotype in schizophrenia. 展开更多
关键词 Catechol-O-methyltransferase Val/Met polymorphism Cognitive reserve Crystallized intelligence negative symptoms SCHIZOPHRENIA
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Micro-power negative pressure wound technique reduces risk of incision infection following loop ileostomy closure
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作者 Deng-Yong Xu Bing-Jun Bai +4 位作者 Lina Shan Hui-Yan Wei Deng-Feng Lin Ya Wang Da Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期186-195,共10页
BACKGROUND Prophylactic loop ileostomy is an effective way to reduce the clinical severity of anastomotic leakage following radical resection of rectal cancer.Incisional surgical site infection(SSI)is a common complic... BACKGROUND Prophylactic loop ileostomy is an effective way to reduce the clinical severity of anastomotic leakage following radical resection of rectal cancer.Incisional surgical site infection(SSI)is a common complication after ileostomy closure.AIM To evaluate the efficacy and safety of the micro-power negative pressure wound technique(MPNPWT)in preventing incisional SSI.METHODS This was a prospective,randomized controlled clinical trial conducted at a single center.A total of 101 consecutive patients who underwent ileostomy closure after rectal cancer surgery with a prophylactic ileostomy were enrolled from January 2019 to December 2021.Patients were randomly allocated into an MPNPWT group and a control group.The MPNPWT group underwent intermittent suturing of the surgical incision with 2-0 Prolene and was covered with a micro-power negative pressure dressing.The surgical outcomes were compared between the MPNPWT(n=50)and control(n=51)groups.Risk factors for incisional SSI were identified using logistic regression.RESULTS There were no differences in baseline characteristics between the MPNPWT(n=50)and control groups(n=51).The incisional SSI rate was significantly higher in the control group than in the MPNPWT group(15.7%vs 2.0%,P=0.031).However,MPNPWT did not affect other surgical outcomes,including intra-abdominal complications,operative time,and blood loss.Postoperative hospital stay length and hospitalization costs did not differ significantly between the two groups(P=0.069 and 0.843,respectively).None of the patients experienced adverse effects of MPNPWT,including skin allergy,dermatitis,and pain.MPNPWT also helped heal the infected incision.Our study indicated that MPNPWT was an independent protective factor[odds ratio(OR)=0.005,P=0.025)]and diabetes was a risk factor(OR=26.575,P=0.029)for incisional SSI.CONCLUSION MPNPWT is an effective and safe way to prevent incisional SSI after loop ileostomy closure. 展开更多
关键词 Micro-power negative pressure technique Ileostomy closure Incisional surgical site infection Infection prevention Postoperative incision
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A Survey on Negative Transfer 被引量:3
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作者 Wen Zhang Lingfei Deng +1 位作者 Lei Zhang Dongrui Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期305-329,共25页
Transfer learning(TL)utilizes data or knowledge from one or more source domains to facilitate learning in a target domain.It is particularly useful when the target domain has very few or no labeled data,due to annotat... Transfer learning(TL)utilizes data or knowledge from one or more source domains to facilitate learning in a target domain.It is particularly useful when the target domain has very few or no labeled data,due to annotation expense,privacy concerns,etc.Unfortunately,the effectiveness of TL is not always guaranteed.Negative transfer(NT),i.e.,leveraging source domain data/knowledge undesirably reduces learning performance in the target domain,and has been a long-standing and challenging problem in TL.Various approaches have been proposed in the literature to address this issue.However,there does not exist a systematic survey.This paper fills this gap,by first introducing the definition of NT and its causes,and reviewing over fifty representative approaches for overcoming NT,which fall into three categories:domain similarity estimation,safe transfer,and NT mitigation.Many areas,including computer vision,bioinformatics,natural language processing,recommender systems,and robotics,that use NT mitigation strategies to facilitate positive transfers,are also reviewed.Finally,we give guidelines on NT task construction and baseline algorithms,benchmark existing TL and NT mitigation approaches on three NT-specific datasets,and point out challenges and future research directions.To ensure reproducibility,our code is publicized at https://github.com/chamwen/NT-Benchmark. 展开更多
关键词 Domain adaptation domain similarity negative transfer positive transfer transfer learning
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Colossal negative magnetoresistance in spin glass Na(Zn,Mn)Sb 被引量:2
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作者 Shuang Yu Yi Peng +5 位作者 Guoqiang Zhao Jianfa Zhao Xiancheng Wang Jun Zhang Zheng Deng Changqing Jin 《Journal of Semiconductors》 EI CAS CSCD 2023年第3期62-67,共6页
We report the study of magnetic and transport properties of polycrystalline and single crystal Na(Zn,Mn)Sb,a new member of“111”type of diluted magnetic materials.The material crystallizes into Cu2Sb-type structure w... We report the study of magnetic and transport properties of polycrystalline and single crystal Na(Zn,Mn)Sb,a new member of“111”type of diluted magnetic materials.The material crystallizes into Cu2Sb-type structure which is isostructural to“111”type Fe-based superconductors.With suitable carrier and spin doping,the Na(Zn,Mn)Sb establishes spin-glass ordering with freezing temperature(Tf)below 15 K.Despite lack of long-range ferromagnetic ordering,Na(Zn,Mn)Sb single crystal still shows sizeable anomalous Hall effect below Tf.Carrier concentration determined by Hall effect measurements is over 1019 cm-3.More significantly,we observe colossal negative magnetoresistance(MR≡[ρ(H)−ρ(0)]/ρ(0))of-94%in the single crystal sample. 展开更多
关键词 colossal negative magnetoresistance spin glass diluted magnetic materials
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Thermally insulating and fire-retardant bio-mimic structural composites with a negative Poisson's ratio for battery protection 被引量:1
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作者 Fengyin Du Zuquan Jin +9 位作者 Ruizhe Yang Menglong Hao Jiawei Wang Gang Xu Wenqiang Zuo Zifan Geng Hao Pan Tian Li Wei Zhang Wei She 《Carbon Energy》 SCIE EI CAS CSCD 2023年第12期83-96,共14页
Battery safety has attracted considerable attention worldwide due to the rapid development of wearable electronics and the steady increase in the production and use of electric vehicles.As battery failures are often a... Battery safety has attracted considerable attention worldwide due to the rapid development of wearable electronics and the steady increase in the production and use of electric vehicles.As battery failures are often associated with mechanical-thermal coupled behaviors,protective shielding materials with excellent mechanical robustness and flame-retardant properties are highly desired to mitigate thermal runaway.However,most of the thermal insulating materials are not strong enough to protect batteries from mechanical abuse,which is one of the most critical scenarios with catastrophic consequences.Here,inspired by wood,we have developed an effective approach to engineer a hierarchical nanocomposite via self-assembly of calcium silicate hydrate and polyvinyl alcohol polymer chains(referred as CSH wood).The versatile protective material CSH wood demonstrates an unprecedented combination of light weight(0.018 g cm-3),high stiffness(204 MPa in the axial direction),negative Poisson's ratio(-0.15),remarkable toughness(6.67×105 J m-3),superior thermal insulation(0.0204 W m-1 K-1 in the radial direction),and excellent fire retardancy(UL94-V0).When applied as a protective cover or a protective layer within battery packages,the tough CSH wood can resist high-impact load and block heat diffusion to block or delay the spread of fire,therefore significantly reducing the risk of property damage or bodily injuries caused by battery explosions.This work provides new pathways for fabricating advanced thermal insulating materials with large scalability and demonstrates great potential for the protection of electronic devices. 展开更多
关键词 battery protection negative Poisson's ratio thermal insulation TOUGHNESS wood-inspired materials
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Statics, vibration, and buckling of sandwich plates with metamaterial cores characterized by negative thermal expansion and negative Poisson's ratio
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作者 Qiao ZHANG Yuxin SUN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第9期1457-1486,共30页
This paper proposes a three-dimensional(3D)Maltese cross metamaterial with negative Poisson’s ratio(NPR)and negative thermal expansion(NTE)adopted as the core layers in sandwich plates,and aims to explore the relatio... This paper proposes a three-dimensional(3D)Maltese cross metamaterial with negative Poisson’s ratio(NPR)and negative thermal expansion(NTE)adopted as the core layers in sandwich plates,and aims to explore the relations between the mechanical responses of sandwich composites and the NPR or NTE of the metamaterial.First,the NPR and NTE of the metamaterial are derived analytically based on energy conservation.The effective elastic modulus and mass density of the 3D metamaterial are obtained and validated by the finite element method(FEM).Subsequently,the general governing equation of the 3D sandwich plate under thermal environments is established based on Hamilton’s principle with the consideration of the von Kármán nonlinearity.The differential quadrature(DQ)FEM(DQFEM)is utilized to obtain the numerical solutions.It is shown that NPR and NTE can enhance the global stiffness of sandwich structures.The geometric parameters of the Maltese cross metamaterial significantly affect the responses of the thermal stress,natural frequency,and critical buckling load. 展开更多
关键词 negative Poisson's ratio(NPR) negative thermal expansion(NTE) sand-wich plate VIBRATION BUCKLING
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Nonreciprocal negative refraction in a dense hot atomic medium
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作者 易海 张红军 孙辉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期50-57,共8页
We investigate the electromagnetic properties of a four-level dense atomic gas medium with Doppler effect.It is shown that the relative permittivity and relative permeability of the medium can be negative simultaneous... We investigate the electromagnetic properties of a four-level dense atomic gas medium with Doppler effect.It is shown that the relative permittivity and relative permeability of the medium can be negative simultaneously with low absorption in the same detuning interval on account of electromagnetically induced transparency.Furthermore,with the suitable parameters,the nonreciprocal negative refraction can be obtained due to the Doppler effect,and the nonreciprocity frequency band can be regulated by adjusting the temperature,the intensity of the control field and the atomic density in this hot atomic medium. 展开更多
关键词 negative refraction NONRECIPROCITY Doppler effect atomic system
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