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依托“第二课堂”多维度开放实验室,拓展实验教学的深度和广度
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作者 乔晋萍 李运超 +14 位作者 南彩云 张媛 魏朔 赵云岺 韩娟 李玉峰 全燕苹 孙根班 李会峰 郭少师 贺勇 邓学彬 张家新 司书峰 欧阳津 《大学化学》 CAS 2024年第7期99-105,共7页
实验教学是培养学生实践能力和创新能力的重要环节,如何突破课堂教学的时空限制有效实现实验资源的开放利用,是高校实验教学中心改革和建设的重要内容。本文以化学国家级实验教学示范中心(北京师范大学)为例,介绍本中心将有组织的“第... 实验教学是培养学生实践能力和创新能力的重要环节,如何突破课堂教学的时空限制有效实现实验资源的开放利用,是高校实验教学中心改革和建设的重要内容。本文以化学国家级实验教学示范中心(北京师范大学)为例,介绍本中心将有组织的“第二课堂活动”纳入实验教学体系,探索并创建了多层次、多维度的实验室开放模式;通过举办丰富的实验竞赛/实践活动,支持大学生开展创新创业、学科竞赛、科学研究和科普宣传等活动,为学生提供了多样化的、以自驱为主、崇尚创新的实践训练机会,从而切实发挥了实验教学中心在创新人才培养中的支撑作用和在基础教育领域的辐射和示范作用。上述举措得力、育人效果显著,值得推广借鉴。 展开更多
关键词 第二课堂 实验竞赛 实验室开放模式 实验教学模式改革
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Expert consensus on odontogenic maxillary sinusitis multi-disciplinary treatment 被引量:1
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作者 Jiang Lin Chengshuo Wang +18 位作者 Xiangdong Wang Faming Chen Wei zhang Hongchen Sun Fuhua Yan Yaping Pan Dongdong Zhu Qintai Yang Shaohua Ge Yao Sun Kuiji Wang yuan zhang Mu Xian Ming Zheng Anchun Mo Xin Xu Hanguo Wang Xuedong Zhou Luo zhang 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期1-14,共14页
Odontogenic maxillary sinusitis (OMS) is a subtype of maxillary sinusitis (MS). It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion. Due to the lack of uniq... Odontogenic maxillary sinusitis (OMS) is a subtype of maxillary sinusitis (MS). It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion. Due to the lack of unique clinical features, OMS is difficult to distinguish from other types of rhinosinusitis. Besides, the characteristic infectious pathogeny of OMS makes it is resistant to conventional therapies of rhinosinusitis. Its current diagnosis and treatment are thus facing great difficulties. The multi-disciplinary cooperation between otolaryngologists and dentists is absolutely urgent to settle these questions and to acquire standardized diagnostic and treatment regimen for OMS. However, this disease has actually received little attention and has been underrepresented by relatively low publication volume and quality. Based on systematically reviewed literature and practical experiences of expert members, our consensus focuses on characteristics, symptoms, classification and diagnosis of OMS, and further put forward multidisciplinary treatment decisions for OMS, as well as the common treatment complications and relative managements. This consensus aims to increase attention to OMS, and optimize the clinical diagnosis and decision-making of OMS, which finally provides evidence-based options for OMS clinical management. 展开更多
关键词 DIAGNOSIS SINUSITIS MAXILLARY
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高产稳产小麦新品种宛麦1326的主要特征特性分析
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作者 杨辉 简俊涛 +6 位作者 王清华 袁璋 李玉鹏 张彬 胡卫丽 谢彦周 李学军 《大麦与谷类科学》 2024年第4期66-70,79,共6页
为全面了解宛麦1326特征特性和生产利用价值,利用宛麦1326参加河南省小麦区域试验和生产试验的数据,分析比较宛麦1326和对照品种郑麦113的区域试验和生产试验产量、产量构成要素、适应性等。结果显示,2017—2018年度、2018—2019年度宛... 为全面了解宛麦1326特征特性和生产利用价值,利用宛麦1326参加河南省小麦区域试验和生产试验的数据,分析比较宛麦1326和对照品种郑麦113的区域试验和生产试验产量、产量构成要素、适应性等。结果显示,2017—2018年度、2018—2019年度宛麦1326在区域试验中平均产量分别为6234.0、8377.5 kg/hm^(2),分别较对照郑麦113增产3.5%、3.3%。宛麦1326在2年区域试验的静态稳定性和普遍适应性分析显示,试验变异系数分别为11.17%、8.05%,均小于对照品种郑麦113。因此,宛麦1326是一个稳定性好、产量潜力大、抗逆性强的小麦品种,适宜在河南省高中水肥地块中晚茬大面积种植。 展开更多
关键词 小麦品种 宛麦1326 稳产多抗 适应性
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Identification and characterization of FpRco1 in regulating vegetative growth and pathogenicity based on T-DNA insertion in Fusarium pseudograminearum
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作者 Haiyang Li yuan zhang +18 位作者 Cancan Qin Zhifang Wang Lingjun Hao Panpan zhang Yongqiang yuan Chaopu Ding Mengxuan Wang Feifei Zan Jiaxing Meng Xunyu Zhuang Zheran Liu Limin Wang Haifeng Zhou Linlin Chen Min Wang Xiaoping Xing Hongxia yuan Honglian Li Shengli Ding 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3055-3065,共11页
Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.... Fusarium pseudograminearum is a devastating pathogen that causes Fusarium crown rot(FCR)in wheat and poses a significant threat to wheat production in terms of grain yield and quality.However,the mechanism by which F.pseudograminearum infects wheat remains unclear.In this study,we aimed to elucidate these mechanisms by constructing a T-DNA insertion mutant library for the highly virulent strain WZ-8A of F.pseudograminearum.By screening this mutant library,we identified nine independent mutants that displayed impaired pathogenesis in barley leaves.Among these mutants,one possessed a disruption in the gene FpRCO1 that is an ortholog of Saccharomyces cerevisiae RCO1,encoding essential component of the Rpd3S histone deacetylase complex in F.pseudograminearum.To further investigate the role of FpRCO1 in F.pseudograminearum,we employed a split-marker approach to knock out FpRCO1 in F.pseudograminearum WZ-8A.FpRCO1 deletion mutants exhibit reduced vegetative growth,conidium production,and virulence in wheat coleoptiles and barley leaves,whereas the complementary strain restores these phenotypes.Moreover,under stress conditions,the FpRCO1 deletion mutants exhibited increased sensitivity to NaCl,sorbitol,and SDS,but possessed reduced sensitivity to H_(2)O_(2)compared to these characteristics in the wild-type strain.RNA-seq analysis revealed that deletion of FpRCO1 affected gene expression(particularly the downregulation of TRI gene expression),thus resulting in significantly reduced deoxynivalenol(DON)production.In summary,our findings highlight the pivotal role of FpRCO1 in regulating vegetative growth and development,asexual reproduction,DON production,and pathogenicity of F.pseudograminearum.This study provides valuable insights into the molecular mechanisms underlying F.pseudograminearum infection in wheat and may pave the way for the development of novel strategies to combat this devastating disease. 展开更多
关键词 Fusarium pseudograminearum T-DNA insertion Rpd3S complex FpRCO1 PATHOGENICITY DON production
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Enhancing potassium-ion storage of Bi_(2)S_(3) through external–internal dual synergism: Ti_(3)C_(2)T_(x) compositing and Cu^(2+) doping
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作者 Dawei Sha Yurong You +5 位作者 Rongxiang Hu Jianxiang Ding Xin Cao yuan zhang Long Pan ZhengMing Sun 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期39-51,共13页
Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode ... Potassium-ion batteries(PIBs)offer a cost-effective and resource-abundant solution for large-scale energy storage.However,the progress of PIBs is impeded by the lack of high-capacity,long-life,and fast-kinetics anode electrode materials.Here,we propose a dual synergic optimization strategy to enhance the K^(+)storage stability and reaction kinetics of Bi_(2)S_(3) through two-dimensional compositing and cation doping.Externally,Bi_(2)S_(3) nanoparticles are loaded onto the surface of three-dimensional interconnected Ti_(3)C_(2)T_(x) nanosheets to stabilize the electrode structure.Internally,Cu^(2+)doping acts as active sites to accelerate K^(+)storage kinetics.Various theoretical simulations and ex situ techniques are used to elucidate the external–internal dual synergism.During discharge,Ti_(3)C_(2)T_(x) and Cu^(2+)collaboratively facilitate K+intercalation.Subsequently,Cu^(2+)doping primarily promotes the fracture of Bi2S3 bonds,facilitating a conversion reaction.Throughout cycling,the Ti_(3)C_(2)T_(x) composite structure and Cu^(2+)doping sustain functionality.The resulting Cu^(2+)-doped Bi2S3 anchored on Ti_(3)C_(2)T_(x)(C-BT)shows excellent rate capability(600 mAh g^(-1) at 0.1 A g^(–1);105 mAh g^(-1) at 5.0 A g^(-1))and cycling performance(91 mAh g^(-1) at 5.0 A g^(-1) after 1000 cycles)in half cells and a high energy density(179 Wh kg–1)in full cells. 展开更多
关键词 Bi_(2)S_(3) cation doping potassium-ion batteries synergic mechanism Ti_(3)C_(2)T_(x)compositing
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Pretreatment and analysis techniques development of TKIs in biological samples for pharmacokinetic studies and therapeutic drug monitoring
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作者 Lan Chen yuan zhang +5 位作者 Yi-Xin zhang Wei-Lai Wang De-Mei Sun Peng-Yun Li Xue-Song Feng Yue Tan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第4期439-459,共21页
Tyrosine kinase inhibitors(TKIs)have emerged as the first-line small molecule drugs in many cancer therapies,exerting their effects by impeding aberrant cell growth and proliferation through the modulation of tyrosine... Tyrosine kinase inhibitors(TKIs)have emerged as the first-line small molecule drugs in many cancer therapies,exerting their effects by impeding aberrant cell growth and proliferation through the modulation of tyrosine kinase-mediated signaling pathways.However,there exists a substantial inter-individual variability in the concentrations of certain TKIs and their metabolites,which may render patients with compromised immune function susceptible to diverse infections despite receiving theoretically efficacious anticancer treatments,alongside other potential side effects or adverse reactions.Therefore,an urgent need exists for an up-to-date review concerning the biological matrices relevant to bioanalysis and the sampling methods,clinical pharmacokinetics,and therapeutic drug monitoring of different TKIs.This paper provides a comprehensive overview of the advancements in pretreatment methods,such as protein precipitation(PPT),liquid-liquid extraction(LLE),solid-phase extraction(SPE),micro-SPE(μ-SPE),magnetic SPE(MSPE),and vortex-assisted dispersive SPE(VA-DSPE)achieved since 2017.It also highlights the latest analysis techniques such as newly developed high performance liquid chromatography(HPLC)and high-resolution mass spectrometry(HRMS)methods,capillary electrophoresis(CE),gas chromatography(GC),supercritical fluid chromatography(SFC)procedures,surface plasmon resonance(SPR)assays as well as novel nanoprobes-based biosensing techniques.In addition,a comparison is made between the advantages and disadvantages of different approaches while presenting critical challenges and prospects in pharmacokinetic studies and therapeutic drug monitoring. 展开更多
关键词 TKIs Microextraction technique HRMS methods Pharmacokinetic studies Therapeutic drug monitoring
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Skeletal phenotypes and molecular mechanisms in aging mice
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作者 Qiao Guan yuan zhang +3 位作者 Zhi-Kun Wang Xiao-Hua Liu Jun Zou Ling-Li zhang 《Zoological Research》 SCIE CSCD 2024年第4期724-746,共23页
Aging is an inevitable physiological process,often accompanied by age-related bone loss and subsequent bone-related diseases that pose serious health risks.Research on skeletal diseases caused by aging in humans is ch... Aging is an inevitable physiological process,often accompanied by age-related bone loss and subsequent bone-related diseases that pose serious health risks.Research on skeletal diseases caused by aging in humans is challenging due to lengthy study durations,difficulties in sampling,regional variability,and substantial investment.Consequently,mice are preferred for such studies due to their similar motor system structure and function to humans,ease of handling and care,low cost,and short generation time.In this review,we present a comprehensive overview of the characteristics,limitations,applicability,bone phenotypes,and treatment methods in naturally aging mice and prematurely aging mouse models(including SAMP6,POLG mutant,LMNA,SIRT6,ZMPSTE24,TFAM,ERCC1,WERNER,and KL/KL-deficient mice).We also summarize the molecular mechanisms of these aging mouse models,including cellular DNA damage response,senescence-related secretory phenotype,telomere shortening,oxidative stress,bone marrow mesenchymal stem cell(BMSC)abnormalities,and mitochondrial dysfunction.Overall,this review aims to enhance our understanding of the pathogenesis of aging-related bone diseases. 展开更多
关键词 AGING Premature aging MICE BONE Gene knockout
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A Hand Features Based Fusion Recognition Network with Enhancing Multi-Modal Correlation
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作者 Wei Wu yuan zhang +2 位作者 Yunpeng Li Chuanyang Li YanHao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期537-555,共19页
Fusing hand-based features in multi-modal biometric recognition enhances anti-spoofing capabilities.Additionally,it leverages inter-modal correlation to enhance recognition performance.Concurrently,the robustness and ... Fusing hand-based features in multi-modal biometric recognition enhances anti-spoofing capabilities.Additionally,it leverages inter-modal correlation to enhance recognition performance.Concurrently,the robustness and recognition performance of the system can be enhanced through judiciously leveraging the correlation among multimodal features.Nevertheless,two issues persist in multi-modal feature fusion recognition:Firstly,the enhancement of recognition performance in fusion recognition has not comprehensively considered the inter-modality correlations among distinct modalities.Secondly,during modal fusion,improper weight selection diminishes the salience of crucial modal features,thereby diminishing the overall recognition performance.To address these two issues,we introduce an enhanced DenseNet multimodal recognition network founded on feature-level fusion.The information from the three modalities is fused akin to RGB,and the input network augments the correlation between modes through channel correlation.Within the enhanced DenseNet network,the Efficient Channel Attention Network(ECA-Net)dynamically adjusts the weight of each channel to amplify the salience of crucial information in each modal feature.Depthwise separable convolution markedly reduces the training parameters and further enhances the feature correlation.Experimental evaluations were conducted on four multimodal databases,comprising six unimodal databases,including multispectral palmprint and palm vein databases from the Chinese Academy of Sciences.The Equal Error Rates(EER)values were 0.0149%,0.0150%,0.0099%,and 0.0050%,correspondingly.In comparison to other network methods for palmprint,palm vein,and finger vein fusion recognition,this approach substantially enhances recognition performance,rendering it suitable for high-security environments with practical applicability.The experiments in this article utilized amodest sample database comprising 200 individuals.The subsequent phase involves preparing for the extension of the method to larger databases. 展开更多
关键词 BIOMETRICS MULTI-MODAL CORRELATION deep learning feature-level fusion
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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity
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作者 Nianwei Xu Renke Kang +4 位作者 Bi zhang yuan zhang Chenxu Wang Yan Bao Zhigang Dong 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期458-475,共18页
Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),... Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining processes.Normal-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue strength.The lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue properties.In this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was developed.Then,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was analyzed.Based on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were furtherpredicted.The predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI indexes.Finally,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted results.According to the critical condition,an SI field where FCI sites appeared in the bulk material could be obtained.In this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%. 展开更多
关键词 surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding
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Ultrasound-guided paravertebral nerve block anesthesia for percutaneous endoscopic laser unroofing treatment of symptomatic simple renal cysts—An innovative ambulatory surgery mode
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作者 Jia Hu yuan zhang +2 位作者 Yong Liu Xiao Yu Shaogang Wang 《Asian Journal of Urology》 CSCD 2024年第1期65-71,共7页
Objective:This study was designed to evaluate the feasibility,efficacy,and safety of percutaneous ureteroscopy laser unroofing as an ambulatory surgery for symptomatic simple renal cysts under multilevel paravertebral... Objective:This study was designed to evaluate the feasibility,efficacy,and safety of percutaneous ureteroscopy laser unroofing as an ambulatory surgery for symptomatic simple renal cysts under multilevel paravertebral nerve block anesthesia.Methods:From December 2015 to September 2017,33 simple renal cyst patients who had surgical indications were enrolled.Under ultrasound guidance,the T10/T11,T11/T12,and T12/L1 paravertebral spaces were identified,and 7-10 mL 0.5%ropivacaine was injected at each segment.Then a puncture needle was placed inside the cyst cavity under ultrasonic monitoring.A guidewire was introduced followed by sequential dilation up to 28/30 Fr.The extra parenchymal portion of the cyst wall was dissociated and incised using a thulium laser,and a pathological examination was performed.Results:Sensory loss to pinprick from T8 to L1 and sensory loss to ice from T6 to L2 were observed in all patients.None of the patients complained of pain during surgery.No serious complications occurred perioperatively.After the surgery,all patients recovered their lower limb muscle strength quickly,got out of bed,resumed oral feeding,and left the hospital within 24 h of admission.The pathologic diagnosis of all cyst walls was a simple renal cyst.The mean follow-up was 35.8 months.At the end of follow-up,the cyst units were reduced in size by more than 50%compared to the preoperative size,and no patient experienced a recurrence.Conclusion:Multi-level paravertebral nerve block for percutaneous ureteroscopy laser unroofing as an ambulatory surgery mode is feasible,safe,and effective for the treatment of simple renal cysts in selected patients. 展开更多
关键词 Paravertebralnerve blockanesthesia Percutaneous puncture Simplerenalcyst UNROOFING Ambulatorysurgery
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Biological soil crusts and their potential applications in the sand land over Qinghai-Tibet Plateau
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作者 yuan zhang BenLi Liu 《Research in Cold and Arid Regions》 CSCD 2024年第1期20-29,共10页
The Qinghai-Tibet Plateau is now experiencing ecological degradation risks as a result of climate change and human activities.The alpine grassland ecology in permafrost zones is fragile and susceptible to deterioratio... The Qinghai-Tibet Plateau is now experiencing ecological degradation risks as a result of climate change and human activities.The alpine grassland ecology in permafrost zones is fragile and susceptible to deterioration due to its high altitude,low temperature,and limited oxygen,which complicates the repair of damaged land.Biological soil crusts(BSCs)are crucial for land restoration in plateau regions because they can thrive in harsh conditions and have environmentally beneficial traits.Inoculated biological soil crust(IBSC)has shown success in low-altitude desert regions,but may not be easily duplicated to the plateau environment.Therefore,it is essential to do a comprehensive and multifaceted analysis of the basic theoretical comprehension and practical application of BSCs on the Tibetan Plateau.This review article aims to provide a brief summary of the ecological significance and the mechanisms related to the creation,growth,and progression of BSCs.It discusses the techniques used for cultivating BSCs in laboratories and using them in the field,focusing on the Qinghai-Tibet Plateau circumstance.We thoroughly discussed the potential and the required paths for further studies.This study may be used as a basis for selecting suitable microbial strains and accompanying supplemental actions for implementing IBSCs in the Qinghai-Tibet Plateau. 展开更多
关键词 Biological soil crusts Qinghai-Tibet Plateau Alpine sand areas Inoculated biological soil crusts technology ALGAE CYANOBACTERIA
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Mental health and insomnia problems in healthcare workers after the COVID-19 pandemic:A multicenter cross-sectional study
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作者 Wei Ding Min-Zhong Wang +8 位作者 Xian-Wei Zeng Zhen-Hua Liu Yao Meng Hui-Ting Hu yuan zhang Yu-Guang Guan Fan-Gang Meng Jian-Guo zhang Shu Wang 《World Journal of Psychiatry》 SCIE 2024年第5期704-714,共11页
BACKGROUND Healthcare workers(HCWs)are at increased risk of contracting coronavirus disease 2019(COVID-19)as well as worsening mental health problems and insomnia.These problems can persist for a long period,even afte... BACKGROUND Healthcare workers(HCWs)are at increased risk of contracting coronavirus disease 2019(COVID-19)as well as worsening mental health problems and insomnia.These problems can persist for a long period,even after the pandemic.However,less is known about this topic.AIM To analyze mental health,insomnia problems,and their influencing factors in HCWs after the COVID-19 pandemic.METHODS This multicenter cross-sectional,hospital-based study was conducted from June 1,2023 to June 30,2023,which was a half-year after the end of the COVID-19 emergency.Region-stratified population-based cluster sampling was applied at the provincial level for Chinese HCWs.Symptoms such as anxiety,depression,and insomnia were evaluated by the Generalized Anxiety Disorder-7,Patient Health Questionnaire-9,and Insomnia Severity Index.Factors influencing the symptoms were identified by multivariable logistic regression.RESULTS A total of 2000 participants were invited,for a response rate of 70.6%.A total of 1412 HCWs[618(43.8%)doctors,583(41.3%)nurses and 211(14.9%)nonfrontline],254(18.0%),231(16.4%),and 289(20.5%)had symptoms of anxiety,depression,and insomnia,respectively;severe symptoms were found in 58(4.1%),49(3.5%),and 111(7.9%)of the participants.Nurses,female sex,and hospitalization for COVID-19 were risk factors for anxiety,depression,and insomnia symptoms;moreover,death from family or friends was a risk factor for insomnia symptoms.During the COVID-19 outbreak,most[1086(76.9%)]of the participating HCWs received psychological interventions,while nearly all[994(70.4%)]of them had received public psychological education.Only 102(7.2%)of the HCWs received individual counseling from COVID-19.CONCLUSION Although the mental health and sleep problems of HCWs were relieved after the COVID-19 pandemic,they still faced challenges and greater risks than did the general population.Identifying risk factors would help in providing targeted interventions.In addition,although a major proportion of HCWs have received public psychological education,individual interventions are still insufficient. 展开更多
关键词 COVID-19 Mental health Psychological symptoms INSOMNIA Sleep disorders Cross-sectional study Epidemiological study
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Transverse mode-coupling instability with longitudinal impedance
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作者 Hai-Sheng Xu Chun-Tao Lin +2 位作者 Na Wang Jing-Ye Xu yuan zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期40-53,共14页
Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle loss.The mechanism of TMCI can be explained by the coupling of transverse coherent oscilla... Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle loss.The mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were included.We performed computations for the circular electron-positron collider(CEPC)and observed a similar phenom-enon.Systematic studies on the influence of longitudinal impedance on the TMCI threshold were conducted.We concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI threshold.Additionally,the real part of the longitudinal impedance assists in increasing the TMCI threshold. 展开更多
关键词 Transverse mode-coupling instability Longitudinal impedance
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Long-term performance of recycled asphalt mixtures containing high RAP and RAS
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作者 Jiangmiao Yu Zengyao Lin +3 位作者 Guilian Zou Huayang Yu Zhen Leng yuan zhang 《Journal of Road Engineering》 2024年第1期36-53,共18页
The application of reclaimed asphalt pavement(RAP)and reclaimed asphalt shingles(RAS)on asphalt pavement can reduce the asphalt paving cost,conserve energy and protect the environment.However,the use of high contents ... The application of reclaimed asphalt pavement(RAP)and reclaimed asphalt shingles(RAS)on asphalt pavement can reduce the asphalt paving cost,conserve energy and protect the environment.However,the use of high contents of RAP and RAS in asphalt pavement may lead to durability issues,especially the fatigue cracking and thermal cracking.It is necessary to conduct a series of analyses on asphalt mixtures containing high RAP and RAS,and seek methods to enhance their long-term performance.This paper provides a comprehensive over-view of the long-term performance of recycled asphalt mixtures containing high contents of RAP and RAS.The findings in this research show that rutting resistance of high recycled asphalt mixtures is not a concern,whereas their resistance to fatigue and thermal cracking is not conclusive.Recycling agents can be used to improve the thermal cracking resistance of high recycled asphalt mixtures.An optimum decision on recycling agents will improve the durability properties of high recycled asphalt mixtures.It is recommended that to use a balanced mixture design approach with testing of the blended asphalt binders will provide better understanding of long-term performance of recycled asphalt mixtures containing high RAP and RAS. 展开更多
关键词 Recycled asphalt mixture Recycling agents Long-term performance CRACKING
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Research on Teaching Reform of Landscape Engineering Course based on the Concept of CDIO
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作者 Zhefeng Li Jianpeng Hu +2 位作者 yuan zhang Ruodong Wu Yang Bai 《Journal of Contemporary Educational Research》 2024年第10期153-158,共6页
With the advancement of new engineering construction,it is urgent to explore the teaching reform of professional courses in the cultivation of landscape architecture professionals in combination with industry needs.In... With the advancement of new engineering construction,it is urgent to explore the teaching reform of professional courses in the cultivation of landscape architecture professionals in combination with industry needs.In order to solve the problems existing in the current Landscape Engineering course,such as traditional teaching methods,insufficient student interest,lack of practical links,and the disconnection between teaching content and industry demand.This study discusses the teaching reform of the Landscape Engineering course based on the CDIO(Conceive-Design-Implement-Operate)concept,aiming at solving the problems mentioned.Through the integration of CDIO mode,the core competencies that students should have are defined,including environmental landscape design and planning,innovative thinking,project management,and so on.The research emphasizes project-driven learning,interdisciplinary knowledge integration,and practical skill training,and puts forward strategies such as teacher training and professional development support to ensure the implementation of the reform.The purpose of the reform was to improve students’professional ability and employment competitiveness,promote the improvement of education quality and the sustainable development of the industry,and exert a positive impact on landscape engineering education and industry progress. 展开更多
关键词 CDIO Curriculum construction Teaching reform Landscape Engineering Landscape architecture
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Tuberculosis Infected T Lymphocyte Spot as a Differential Diagnosis of Pulmonary Tuberculosis and Choriocarcinoma Recurrence: A Case Report and Review of the Literature
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作者 Qi Wu Zhaoping Chu +7 位作者 Jun Dai Ligang Jia Xinling Wang Lihui Li Jie Li yuan zhang Ping Yan Jianxiang Hou 《Journal of Biosciences and Medicines》 2023年第9期31-36,共6页
Introduction: Choriocarcinoma is an aggressive tumor, whose incidence is 0.18 per 100,000 women between the ages of 15 and 49 years [1]. Although its prognosis has improved with the development of chemotherapy regimen... Introduction: Choriocarcinoma is an aggressive tumor, whose incidence is 0.18 per 100,000 women between the ages of 15 and 49 years [1]. Although its prognosis has improved with the development of chemotherapy regimens, the mortality rate of patients with brain metastases is reportedly 29.7% [2]. After chemotherapy, most often, the reappearance of masses in pulmonary is considered to be a sign of relapse. Case presentation: The patient was a 32-year-old Asian Chinese female who delivered a dead male infant at 33 weeks gestation. The placenta appeared to be normal. The major presentation was a haemorrhage of the vagina. The patient received combined treatment with systematic multi-agent chemotherapy and whole-brain radiation therapy at the General Hospital of Hebei Province and achieved complete remission. Two years after remission, a chest CT scan revealed a mass in the right lung that had become larger over 6 months. The patient’s serum β-human chorionic gonadotropin (β-HCG) level was normal, and the tuberculosis infected T lymphocyte spot (T-SPOT.TB) tests were positive. The patient was started on anti-tuberculosis therapy, after which the size of her right lung mass decreased. Conclusion: Lung masses after choriocarcinoma require extensive laboratory and imaging exams to exclude recurrence. This case highlights the importance of differential diagnoses of lung masses in patients with choriocarcinomas. Imaging studies, β-HCG and local lesion resection should be employed to rule out choriocarcinoma recurrence. 展开更多
关键词 CHORIOCARCINOMA TUBERCULOSIS
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国外老年群体社交媒体使用研究前沿转向及热点趋势研究
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作者 张媛 张盛颖 《全球传媒学刊》 2023年第6期77-93,共17页
在各国推进积极老龄化的背景下,老年群体的社交媒体使用日益成为学界关注的热点议题。本文对Web of Science数据库收录的549篇关于老年群体社交媒体使用的文献进行知识图谱的可视化分析,研究发现:国外关于老年群体社交媒体使用的研究对... 在各国推进积极老龄化的背景下,老年群体的社交媒体使用日益成为学界关注的热点议题。本文对Web of Science数据库收录的549篇关于老年群体社交媒体使用的文献进行知识图谱的可视化分析,研究发现:国外关于老年群体社交媒体使用的研究对象由单一群体研究转向多类别、跨地域群体研究;研究视角由单一学科研究步入多学科交互研究;研究内容由表象研究向数字接入、身心感知、社会支持等深度研究推进;研究方法由横向研究过渡到探索性、实验性的纵向研究。 展开更多
关键词 老年群体 社交媒体使用 CITESPACE 可视化分析
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轨道交通对住宅的溢价效应与价值捕获机制——以合肥轨道交通1号线为例 被引量:1
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作者 张袁 顾大治 +2 位作者 刘傲霜 赵梓言 龚咏喜 《热带地理》 CSCD 北大核心 2023年第10期1961-1972,共12页
以合肥轨道交通1号线为例,首先,构建站点区域的住宅价格拟合模型,其次,解析住宅的空间增值规律与各拟合指标的溢价效力,并进一步提取站点区域住宅项目溢价增值特征,最后梳理价值捕获机制并提出优化策略。研究表明:1)合肥轨道交通1号线... 以合肥轨道交通1号线为例,首先,构建站点区域的住宅价格拟合模型,其次,解析住宅的空间增值规律与各拟合指标的溢价效力,并进一步提取站点区域住宅项目溢价增值特征,最后梳理价值捕获机制并提出优化策略。研究表明:1)合肥轨道交通1号线对沿线住宅价格的影响显著,并随距轨道交通站点距离的增加,住宅价格不断衰减。2)不同指标要素对站点区域住宅溢价效力不同,其中区位交通层面指标的溢价贡献最大,其次是邻里环境层面指标,建筑形态层面指标的贡献最小。3)依据模型得分结果构建四元组对站点区域进行评估,能识别站点区域的溢价规律与地理效应,建立轨道交通站点区域溢价效应与价值捕获的系统联系。同时基于合肥实践,针对中国公有制土地制度,通过剖析轨道融资与溢价捕获的互动关系,提出了适应性的土地利用策略与溢价分配方法,以推动轨道交通溢价归公、城市居民共享地利和社会经济可持续发展。 展开更多
关键词 轨道交通 站点分类 住宅价格 溢价效应 价值捕获 合肥
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Selecting the Technology of Sodium Silicate Modified Poplar with the Highest Performance by Fuzzy Orthogonal Method 被引量:1
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作者 Xiaoqian Bi Pengfei Guan +3 位作者 Ping Li yuan zhang Xingong Li Yingfeng Zuo 《Journal of Renewable Materials》 SCIE EI 2023年第5期2399-2415,共17页
Sodium silicate modification can improve the overall performance of wood.The modification process has a great influence on the properties of modified wood.In this study,a new method was introduced to analyze the wood ... Sodium silicate modification can improve the overall performance of wood.The modification process has a great influence on the properties of modified wood.In this study,a new method was introduced to analyze the wood modification process,and the properties of modified wood were studied.Poplar wood was modified with sodium silicate by vacuum-pressure impregnation.After screening using single-factor experiments,an orthogonal experiment was carried out with solution concentration,impregnation time,impregnation pressure,and the cycle times as experimental factors.The modified poplar with the best properties was selected by fuzzy mathematics and characterized by SEM,FT-IR,XRD and TG.The results showed that some lignin and hemicellulose were removed from the wood due to the alkaline action of sodium silicate,and the orderly crystal area of poplar became disorderly,resulting in the reduction of crystallinity of the modified poplar wood.FT-IR analysis showed that sodium silicate was hydrolyzed to form polysilicic acid in wood,and structural analysis revealed the formation of Si-O-Si and Si-O-C,indicating that sodium silicate reacted with fibers on the wood cell wall.TG-DTG curves showed that the final residual mass of modified poplar wood increased from 25%to 67%,and the temperature of the maximum loss rate decreased from 343℃ to 276℃.The heat release and smoke release of modified poplar wood decreased obviously.This kind of material with high strength and fire resistance can be used in the outdoor building and indoor furniture. 展开更多
关键词 Poplar wood sodium silicate impregnation modification fuzzy orthogonal method process optimization flame retardant
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Influence of quick release valve on braking performance and coupler force of heavy haul train 被引量:1
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作者 Wei Wei yuan zhang +1 位作者 Jun zhang Xubao Zhao 《Railway Engineering Science》 2023年第2期153-161,共9页
We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of tr... We establish a simulation model based on the theory of air flow to analyze the accelerated release effect of the quick release valve inside the air brake control valve.In addition, the combined simulation system of train air brake system and longitudinal train dynamics is used to analyze how the parameters of the quick release valve in the 120/120–1 brake control valve affect the propagation characteristics of the train brake pipe pressure wave, the release action range of the accelerated brake, and the longitudinal coupler force for a 20,000-ton heavy haul train on the section of the Datong–Qinhuangdao Railway. The results show that the quick release valve can effectively accelerate the rising speed of the train brake pipe pressure during the initial release, as the accelerated release effect is evident before the train brake pipe pressure reaches582 k Pa. The quick release valve can effectively accelerate the release of the rear cars, reducing the longitudinal coupler force impact due to time delay of the release process. The quick release valve can effectively reduce the tensile coupler force in the train by as much as 20% in certain cases. 展开更多
关键词 Brake system Release characteristics Quick release valve Coupler force Heavy haul train
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