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Clinical manifestation,lifestyle,and treatment patterns of chronic erosive gastritis:A multicenter real-world study in China 被引量:1
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作者 Ying-Yun Yang Ke-Min Li +18 位作者 Gui-Fang Xu Cheng-Dang Wang Hua Xiong Xiao-Zhong Wang Chun-Hui Wang Bing-Yong Zhang Hai-Xing Jiang Jing Sun Yan Xu Li-Juan Zhang Hao-Xuan Zheng Xiang-Bin Xing Liang-Jing Wang Xiu-Li Zuo Shi-Gang Ding Rong Lin Chun-Xiao Chen Xing-Wei Wang Jing-Nan Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1108-1120,共13页
BACKGROUND Although chronic erosive gastritis(CEG)is common,its clinical characteristics have not been fully elucidated.The lack of consensus regarding its treatment has resulted in varied treatment regimens.AIM To ex... BACKGROUND Although chronic erosive gastritis(CEG)is common,its clinical characteristics have not been fully elucidated.The lack of consensus regarding its treatment has resulted in varied treatment regimens.AIM To explore the clinical characteristics,treatment patterns,and short-term outcomes in CEG patients in China.METHODS We recruited patients with chronic non-atrophic or mild-to-moderate atrophic gastritis with erosion based on endoscopy and pathology.Patients and treating physicians completed a questionnaire regarding history,endoscopic findings,and treatment plans as well as a follow-up questionnaire to investigate changes in symptoms after 4 wk of treatment.RESULTS Three thousand five hundred sixty-three patients from 42 centers across 24 cities in China were included.Epigastric pain(68.0%),abdominal distension(62.6%),and postprandial fullness(47.5%)were the most common presenting symptoms.Gastritis was classified as chronic non-atrophic in 69.9%of patients.Among those with erosive lesions,72.1%of patients had lesions in the antrum,51.0%had multiple lesions,and 67.3%had superficial flat lesions.In patients with epigastric pain,the combination of a mucosal protective agent(MPA)and proton pump inhibitor was more effective.For those with postprandial fullness,acid regurgitation,early satiety,or nausea,a MPA appeared more promising.CONCLUSION CEG is a multifactorial disease which is common in Asian patients and has non-specific symptoms.Gastroscopy may play a major role in its detection and diagnosis.Treatment should be individualized based on symptom profile. 展开更多
关键词 Chronic erosive gastritis SYMPTOM Endoscopic findings Treatment pattern Real-world
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Analysis of the History and Current Situation of the Development of General Practice Teaching Clinics in China
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作者 Xiaotong Huo Yajun Lian 《Open Journal of Preventive Medicine》 2024年第2期29-38,共10页
A summary of the exploration of the teaching mode of the general practice teaching clinic, a summary of the deficiencies of the teaching clinic and a summary of the significance of the establishment of the general pra... A summary of the exploration of the teaching mode of the general practice teaching clinic, a summary of the deficiencies of the teaching clinic and a summary of the significance of the establishment of the general practice teaching clinic are presented with a view to promoting the development of general practice and cultivating more excellent successors in general practice. 展开更多
关键词 General Practice teaching Clinic teaching Models teaching Deficiencies in the Clinic Significance of the teaching Clinic
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Exploration on Teaching Reform of Synthetic Biology Course Based on the New Engineering Concept
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作者 Jie CHENG Shunyang HU +3 位作者 Fangkun YU Jiamin ZHANG Bingliang LIU Yin ZHANG 《Agricultural Biotechnology》 2024年第3期86-89,共4页
Synthetic biology is a new frontier of life science,which aims to design,transform and even synthesize organisms with engineering design concept.Doing a good job in the teaching of"synthetic biology"is of gr... Synthetic biology is a new frontier of life science,which aims to design,transform and even synthesize organisms with engineering design concept.Doing a good job in the teaching of"synthetic biology"is of great significance to the cultivation and reserve of biotechnology professionals in China,and also has an important impact on students' employment competitiveness.Under the background of"new engineering",the course reform of"synthetic biology"was carried out in terms of the construction of teaching staff,teaching methods,students' participation and the innovation of course content,and specific reform suggestions were put forward,hoping to effectively promote the sustainable development of"synthetic biology"and effectively improve the quality of education. 展开更多
关键词 teaching reform Synthetic biology teaching innovation teaching methods
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Study on Epidemiological Profile, Clinical Profile, and Angiographic Patterns in Acute Coronary Syndrome Patients in a Tertiary Health Care Center in Haryana
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作者 Ghritachi Sandal Kuldip Singh Laller +1 位作者 Ashwani Kumar Yadav Sunil Kumar Bamel 《World Journal of Cardiovascular Diseases》 CAS 2024年第10期664-680,共17页
Background: Cardiovascular diseases are the leading cause of death in India, with coronary artery disease (CAD) accounting for a majority of the deaths. There are few large registries on acute coronary syndrome (ACS) ... Background: Cardiovascular diseases are the leading cause of death in India, with coronary artery disease (CAD) accounting for a majority of the deaths. There are few large registries on acute coronary syndrome (ACS) from India. Our aim is to study the clinical and epidemiological profile of ACS PATIENTS presenting to our institute, including their angiographic features. Methods: This hospital-based observational, single tertiary care center, prospective study was conducted on patients admitted in the Department of Cardiology at a tertiary care center in Haryana. The study included 400 patients aged greater than 18 years who were admitted with the diagnosis of ACS, and it was carried out for 1 year. The epidemiological profile, clinical history, risk factors, electrocardiogram findings, and angiographic pattern were studied and analyzed with appropriate statistical tools. Results: The mean age of the study population was 55.12 ± 11.78 years. Male and female ratio was 2.4:1. The majority of the patients came from rural background (80%);24% of the patients were illiterate. Smoking was the most common risk factor (51.5%) in our study population followed by hypertension (40%) and diabetes (28%). Unstable angina was the most common type of ACS, which was found in 68.25% of patients. Premature CAD was found in 27.8% of patients and obstructive CAD was found in 63% of patients. Coronary angiography revealed that 39% had single vessel disease (SVD), 23.5% had double vessel disease (DVD), and 27.5% had triple vessel disease (TVD). LAD was more commonly involved, followed by RCA and LCX. Within the first 24 hours, 67% of patients sought medical assistance and only 38.5% received definitive treatment, suggesting a delay in seeking definitive treatment in our study population. Conclusion: The study suggests that unstable angina is the most common form of ACS in the study population, which is mostly of rural background with significant delay in seeking medical help. Smoking is the most common risk factor in the study population. 展开更多
关键词 Acute Coronary Syndrome Angiographic Pattern Unstable Angina
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Practical effect of different teaching modes in teaching gastrointestinal surgery nursing
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作者 Xiao-Juan Rong Zhen Ning 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期166-172,共7页
BACKGROUND With the continuous development and progress of medical technology,the position of surgical nursing in the field of clinical medicine is becoming in-creasingly prominent.As an important branch of the surgic... BACKGROUND With the continuous development and progress of medical technology,the position of surgical nursing in the field of clinical medicine is becoming in-creasingly prominent.As an important branch of the surgical field,the nursing requirements and difficulty of gastrointestinal surgery are also increasing.In order to improve the teaching quality of nursing care in gastrointestinal surgery,many educators and researchers are actively exploring new teaching methods.Among them,the teaching method case-based learning(CBL),scene-simulated learning(SSL),task-based learning(TBL),combining self-evaluation and training mode is considered as an effective method.This method aims to help students to better master knowledge and skills and improve their comprehensive quality by cultivating their self-evaluation ability.AIM To explore the practical effect of CBL-SSL-TBL combined with training mode and student self-assessment in nursing teaching of gastrointestinal surgery.METHODS Seventy-one nursing interns in our hospital from December 2020 to December 2021 were selected.According to different teaching modes,they were divided into observation group CBL-SSL-TBL combined with training mode combined with student self-assessment and control group(conventional teaching mode),of which 36 were in observation group and 35 were in control group.The results of operational skills,theoretical knowledge,nursing students'satisfaction,learning effectiveness questionnaire and teaching effect were compared between the two groups.RESULTS Compared between the two groups,the operational skills and theoretical knowledge scores of the observation group were higher than those of the control group,and the difference was statistically significant(P<0.05).Compared between the two groups,the total satisfaction ratio of the observation group was higher than that of the control group,the difference was statistically significant(P<0.05).Compared between the two groups,the observation group was lower than the control group in the questionnaire results of learning efficacy,and the difference was statistically significant(P<0.05).Compared between the two groups,the proportion of thinking ability,subjective initiative and understanding of theoretical knowledge in the observation group was higher than that in the control group,the difference was statistically significant(P<0.05).CONCLUSION The use of CBL-SSL-TBL combined with training mode and student self-assessment in gastrointestinal surgery nursing teaching can improve the operational skills of nursing interns,theoretical knowledge and satisfaction scores of nursing students,improve the results of learning efficiency questionnaire and teaching effect,which can be popularized in clinical teaching. 展开更多
关键词 Gastrointestinal surgery Nursing teaching teaching model Practical effect Learning ability
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Tuning the diffusion constant to optimize the readout of positional information of spatial concentration patterns
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作者 江嘉杰 罗春雄 刘峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期579-586,共8页
Positional information encoded in spatial concentration patterns is crucial for the development of multicellular organisms.However,it is still unclear how such information is affected by the physically dissipative dif... Positional information encoded in spatial concentration patterns is crucial for the development of multicellular organisms.However,it is still unclear how such information is affected by the physically dissipative diffusion process.Here we study one-dimensional patterning systems with analytical derivation and numerical simulations.We find that the diffusion constant of the patterning molecules exhibits a nonmonotonic effect on the readout of the positional information from the concentration patterns.Specifically,there exists an optimal diffusion constant that maximizes the positional information.Moreover,we find that the energy dissipation due to the physical diffusion imposes a fundamental upper limit on the positional information. 展开更多
关键词 pattern formation positional information mutual information DIFFUSION
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Exploration of Teaching Reform of Food Machinery and Equipment Course Based on New Engineering Concept
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作者 Bingliang LIU Fangkun YU +2 位作者 Jie CHENG Yin ZHANG Dayu LIU 《Asian Agricultural Research》 2024年第7期53-55,共3页
The new engineering concept aims to train high-quality engineering talents to meet the needs of future science and technology and industrial development through the reform of education and teaching.Under the backgroun... The new engineering concept aims to train high-quality engineering talents to meet the needs of future science and technology and industrial development through the reform of education and teaching.Under the background of"new engineering",by introducing cutting-edge knowledge of the industry and interdisciplinary integration,adopting innovative teaching methods such as project-driven teaching and flipped classroom,strengthening experimental teaching and school-enterprise cooperation,and establishing comprehensive evaluation and feedback mechanism,Food Machinery and Equipment course is reformed to improve the teaching quality and train high-quality engineering talents to meet the needs of modern food processing industry. 展开更多
关键词 teaching reform Food machinery and equipment teaching innovation teaching method
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Temporal and spatial evolution of global major grain trade patterns
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作者 Ziqi Yin Jiaxuan Hu +3 位作者 Jing Zhang Xiangyang Zhou Lingling Li Jianzhai Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1075-1086,共12页
The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain ... The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks. 展开更多
关键词 grain trade pattern evolution complex network
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Research on Blended Teaching Mode:A Case Study of Floristry
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作者 Xiaoru CHEN 《Plant Diseases and Pests》 2024年第1期33-35,共3页
In order to better carry out research on education and teaching,the author consulted relevant literature on blended teaching mode from 2011-2021 through CNKI,Web of Science and other websites,summarized and analyzed t... In order to better carry out research on education and teaching,the author consulted relevant literature on blended teaching mode from 2011-2021 through CNKI,Web of Science and other websites,summarized and analyzed the research status of blended teaching mode,in order to lay a good foundation for studying blended teaching mode in course teaching. 展开更多
关键词 Blended teaching teaching mode Research review
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Plant-based dietary patterns and risk of esophageal cancer:A prospective cohort study spanning 17 years
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作者 Xiaorui Zhang Feifan He +6 位作者 Jiayue Li Ru Chen Xinqing Li Li Li Fen Liu Shaoming Wang Wenqiang Wei 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第1期36-45,共10页
Objective: Plant-based diets have multiple health benefits for cancers;however, little is known about the association between plant-based dietary patterns and esophageal cancer(EC).This study presents an investigation... Objective: Plant-based diets have multiple health benefits for cancers;however, little is known about the association between plant-based dietary patterns and esophageal cancer(EC).This study presents an investigation of the prospective associations among three predefined indices of plant-based dietary patterns and the risk of EC.Methods: We performed endoscopic screening for 15,709 participants aged 40-69 years from two high-risk areas of China from January 2005 to December 2009 and followed the cohort until December 31, 2022. The overall plant-based diet index(PDI), healthful plant-based diet index(h PDI), and unhealthful plant-based diet index(u PDI), were calculated using survey responses to assess dietary patterns. We applied Cox proportional hazard regression to estimate the multivariable hazard ratios(HRs) and 95% confidence intervals(95% CIs) of EC across 3plant-based diet indices and further stratified the analysis by subgroups.Results: The final study sample included 15,184 participants in the cohort. During a follow-up of 219,365person-years, 176 patients with EC were identified. When the highest quartile was compared with the lowest quartile, the pooled multivariable-adjusted HR of EC was 0.50(95% CI, 0.32-0.77) for h PDI. In addition, the HR per 10-point increase in the h PDI score was 0.42(95% CI, 0.27-0.66) for ECs. Conversely, u PDI was positively associated with the risk of EC, and the HR was 1.80(95% CI, 1.16-2.82). The HR per 10-point increase in the u PDI score was 1.90(95% CI, 1.26-2.88) for ECs. The associations between these scores and the risk of EC were consistent in most subgroups. These results remained robust in sensitivity analyses.Conclusions: A healthy plant-based dietary pattern was associated with a reduced risk of EC. Emphasizing the healthiness and quality of plant-based diets may be important for preventing the development of EC. 展开更多
关键词 Esophageal cancer DIET dietary pattern EPIDEMIOLOGY NUTRITION prospective cohort study
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Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains
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作者 Ling-Yun Wu Shuang-Quan Huang Ze-Yu Tong 《Plant Diversity》 SCIE CAS CSCD 2024年第5期661-670,共10页
Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distin... Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine environments.To answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern China.We also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen deposition.Stigmatic pollen deposition was more variable in distylous species than in homostylous species.Although seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous self-pollination.Our findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity. 展开更多
关键词 Biodiversity hotspot Elevation gradient FAGOPYRUM Stigmatic pollen load Temporal pattern
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A Structured Method of Teaching Epidural Block reduces the incidence of accidental dural puncture in inexperienced trainees.
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作者 Marco Scorzoni Gianluigi Gonnella +4 位作者 Emanuele Capogna Marina Campione Gaetano Draisci Matteo Velardo Giorgio Capogna 《Open Journal of Anesthesiology》 2024年第4期131-135,共5页
Background: The rate of accidental dural puncture is particularly high during the period of training, especially in novices. The structured epidural teaching model (SETM) includes three standardized video lessons, the... Background: The rate of accidental dural puncture is particularly high during the period of training, especially in novices. The structured epidural teaching model (SETM) includes three standardized video lessons, the construction of a 3D epidural module by trainees and practical training by using an epidural simulator with and without the CompuFlo™ Epidural instrument. In this study we report the retrospective analysis of the accidental dural puncture rate of inexperienced trainees during their 6 months clinical practice rotation in obstetrics before and after the introduction of the SETM in our Institution. Method: We evaluated the incidence of accidental dural puncture before the introduction of the SETM methodology and afterwards by analyzing our departmental database from February 2019 to January 2023. All epidural blocks were executed by trainees who had never previously performed an epidural block and were about to begin their obstetrics rotation. Results: We analyzed 7415 epidurals: 3703 were performed before the introduction of the SETM methodology (control group) and 3712 afterwards (study group). The incidence of accidental dural puncture was 0.37% for the control group and 0.13% for the study group (p<.05). The probability of making an accidental dural puncture was 64% (OR: 0.36) lower for trainees who had the training than for those who did not. Conclusions: After the introduction of the structured teaching method, we observed a significant reduction of accidental dural puncture during the training period. We hope that our observation will encourage a constructive discussion among experts about the need to use standardized and validated tools as a valuable aid in teaching epidural anesthesia. 展开更多
关键词 teaching epidural Anesthesia obstetrical Anesthesia ANESTHESIA
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Thinking on Improving Presentation Teaching-Based on the Empirical Analysis of Presentation in College English Classes of Junior Non-English Majors in Universities of Science and Engineering
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作者 DONG Lin 《Sino-US English Teaching》 2024年第9期424-427,共4页
Based on the empirical investigation of presentation in college English classes for junior non-English majors in science and engineering universities,the author explains her own thinking on how to improve presentation... Based on the empirical investigation of presentation in college English classes for junior non-English majors in science and engineering universities,the author explains her own thinking on how to improve presentation teaching from four aspects:setting teaching objectives,selecting teaching contents,using teaching methods,and evaluating and implementing methods. 展开更多
关键词 PRESENTATION teaching objective teaching content teaching method evaluation on implementation THINKING
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Three-dimensional numerical analysis of plant-soil hydraulic interactions on pore water pressure of vegetated slope under different rainfall patterns
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作者 Haowen Guo Charles Wang Wai Ng Qi Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第9期3696-3706,共11页
Understanding the pore water pressure distribution in unsaturated soil is crucial in predicting shallow landslides triggered by rainfall,mainly when dealing with different temporal patterns of rainfall intensity.Howev... Understanding the pore water pressure distribution in unsaturated soil is crucial in predicting shallow landslides triggered by rainfall,mainly when dealing with different temporal patterns of rainfall intensity.However,the hydrological response of vegetated slopes,especially three-dimensional(3D)slopes covered with shrubs,under different rainfall patterns remains unclear and requires further investigation.To address this issue,this study adopts a novel 3D numerical model for simulating hydraulic interactions between the root system of the shrub and the surrounding soil.Three series of numerical parametric studies are conducted to investigate the influences of slope inclination,rainfall pattern and rainfall duration.Four rainfall patterns(advanced,bimodal,delayed,and uniform)and two rainfall durations(4-h intense and 168-h mild rainfall)are considered to study the hydrological response of the slope.The computed results show that 17%higher transpiration-induced suction is found for a steeper slope,which remains even after a short,intense rainfall with a 100-year return period.The extreme rainfalls with advanced(PA),bimodal(PB)and uniform(PU)rainfall patterns need to be considered for the short rainfall duration(4 h),while the delayed(PD)and uniform(PU)rainfall patterns are highly recommended for long rainfall durations(168 h).The presence of plants can improve slope stability markedly under extreme rainfall with a short duration(4 h).For the long duration(168 h),the benefit of the plant in preserving pore-water pressure(PWP)and slope stability may not be sufficient. 展开更多
关键词 Root-soil interactions Rainfall patterns Slope stability Three-dimensional(3D)
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From furnace up to freezer:Elevational patterns of plant diversity in Mount Palvar,a semi-arid Irano-Turanian mountain range of southwest Asia
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作者 Atefeh GHORBANALIZADEH Moslem DOOSTMOHAMMADI 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2236-2248,共13页
Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse environments.As an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical re... Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse environments.As an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical region.Understanding plant diversity patterns with increasing elevation is of high significance,not least for conservation planning.We studied the pattern of species richness,Shannon diversity,endemic richness,endemics ratio,and richness of life forms along a 3900 m elevational transect in Mount Palvar,overlooking the Lut Desert in Southeast Iran.We also analyzed the effect of environmental variables on species turnover along the vertical gradient.A total of 120 vegetation plots(10 m×10 m)were sampled along the elevational transect containing species and environmental data.To discover plant diversity pattern along the elevational gradient,generalized additive model(GAM)was used.Non-metric multidimensional scaling(NMDS)was applied for illustrating the correlation between species composition and environmental variables.We found hump-shaped pattern for species richness,Shannon diversity,endemic richness,and species richness of different life forms,but a monotonic increasing pattern for ratio of endemic species from low to high elevations.Our study confirms the humped pattern of species richness peaking at intermediate elevations along a complete elevational gradient in a semi-arid mountain.The monotonic increase of endemics ratio with elevation in our area as a case study is consistent with global increase of endemism with elevation.According to our results,temperature and precipitation are two important climatic variables that drive elevational plant diversity,particularly in seasonally dry areas.Our study suggests that effective conservation and management are needed for this low latitude mountain area along with calling for long-term monitoring for species redistribution. 展开更多
关键词 Elevational gradient Biodiversity ENDEMIC Generalized additive model Hump-shaped pattern Irano-Turanian region
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Real-time generation of circular patterns in electron beam lithography
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作者 Zhengjie Li Bohua Yin +3 位作者 Botong Sun Jingyu Huang Pengfei Wang Li Han 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第3期90-98,共9页
Electron beam lithography(EBL)involves the transfer of a pattern onto the surface of a substrate byfirst scanning a thin layer of organicfilm(called resist)on the surface by a tightly focused and precisely controlled el... Electron beam lithography(EBL)involves the transfer of a pattern onto the surface of a substrate byfirst scanning a thin layer of organicfilm(called resist)on the surface by a tightly focused and precisely controlled electron beam(exposure)and then selectively removing the exposed or nonexposed regions of the resist in a solvent(developing).It is widely used for fabrication of integrated cir-cuits,mask manufacturing,photoelectric device processing,and otherfields.The key to drawing circular patterns by EBL is the graphics production and control.In an EBL system,an embedded processor calculates and generates the trajectory coordinates for movement of the electron beam,and outputs the corresponding voltage signal through a digital-to-analog converter(DAC)to control a deflector that changes the position of the electron beam.Through this procedure,it is possible to guarantee the accuracy and real-time con-trol of electron beam scanning deflection.Existing EBL systems mostly use the method of polygonal approximation to expose circles.A circle is divided into several polygons,and the smaller the segmentation,the higher is the precision of the splicing circle.However,owing to the need to generate and scan each polygon separately,an increase in the number of segments will lead to a decrease in the overall lithography speed.In this paper,based on Bresenham’s circle algorithm and exploiting the capabilities of afield-programmable gate array and DAC,an improved real-time circle-producing algorithm is designed for EBL.The algorithm can directly generate cir-cular graphics coordinates such as those for a single circle,solid circle,solid ring,or concentric ring,and is able to effectively realizes deflection and scanning of the electron beam for circular graphics lithography.Compared with the polygonal approximation method,the improved algorithm exhibits improved precision and speed.At the same time,the point generation strategy is optimized to solve the blank pixel and pseudo-pixel problems that arise with Bresenham’s circle algorithm.A complete electron beam deflection system is established to carry out lithography experiments,the results of which show that the error between the exposure results and the preset pat-terns is at the nanometer level,indicating that the improved algorithm meets the requirements for real-time control and high precision of EBL. 展开更多
关键词 Electron beam lithography Circle production Micro–nano fabrication Pattern generator
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Spatial patterns of the Brusselator model with asymmetric Lévy diffusion
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作者 Hongwei Yin Shangtao Yang +2 位作者 Xiaoqing Wen Haohua Wang Shufen Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期129-136,共8页
The formation of spatial patterns is an important issue in reaction–diffusion systems.Previous studies have mainly focused on the spatial patterns in reaction–diffusion models equipped with symmetric diffusion(such ... The formation of spatial patterns is an important issue in reaction–diffusion systems.Previous studies have mainly focused on the spatial patterns in reaction–diffusion models equipped with symmetric diffusion(such as normal or fractional Laplace diffusion),namely,assuming that spatial environments of the systems are homogeneous.However,the complexity and heterogeneity of spatial environments of biochemical reactions in vivo can lead to asymmetric diffusion of reactants.Naturally,there arises an open question of how the asymmetric diffusion affects dynamical behaviors of biochemical reaction systems.To answer this,we build a general asymmetric L´evy diffusion model based on the theory of a continuous time random walk.In addition,we investigate the two-species Brusselator model with asymmetric L´evy diffusion,and obtain a general condition for the formation of Turing and wave patterns.More interestingly,we find that even though the Brusselator model with symmetric diffusion cannot produce steady spatial patterns for some parameters,the asymmetry of L´evy diffusion for this model can produce wave patterns.This is different from the previous result that wave instability requires at least a three-species model.In addition,the asymmetry of L´evy diffusion can significantly affect the amplitude and frequency of the spatial patterns.Our results enrich our knowledge of the mechanisms of pattern formation. 展开更多
关键词 asymmetric Lévy diffusion Turing and wave patterns Brusselator model
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Acute effect of foot strike patterns on in vivo tibiotalar and subtalar joint kinematics during barefoot running
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作者 Dongqiang Ye Lu Li +4 位作者 Shen Zhang Songlin Xiao Xiaole Sun Shaobai Wang Weijie Fu 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期108-117,共10页
Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patte... Background:Foot kinematics,such as excessive eversion and malalignment of the hindfoot,are believed to be associated with running-related injuries.The maj ority of studies to date show that different foot strike patterns influence these specific foot and ankle kinematics.However,technical deficiencies in traditional motion capture approaches limit knowledge of in vivo joint kinematics with respect to rearfoot and forefoot strike patterns(RFS and FFS,respectively).This study uses a high-speed dual fluoroscopic imaging system(DFIS)to determine the effects of different foot strike patterns on 3D in vivo tibiotalar and subtalar joints kinematics.Methods:Fifteen healthy male recreational runners underwent foot computed tomography scanning for the construction of 3-dimensional models.A high-speed DFIS(100 Hz)was used to collect 6 degrees of freedom kinematics for participants’tibiotalar and subtalar joints when they adopted RFS and FFS in barefoot condition.Results:Compared with RFS,FFS exhibited greater internal rotation at 0%-20%of the stance phase in the tibiotalar joint.The peak internal rotation angle of the tibiotalar joint under FFS was greater than under RFS(p<0.001,Cohen’s d=0.92).RFS showed more dorsiflexion at 0%-20%of the stance phase in the tibiotalar joint than FFS.RFS also presented a larger anterior translation(p<0.001,Cohen’s d=1.28)in the subtalar joint at i nitial contact than FFS.Conclusion:Running with acute barefoot FFS increases the internal rotation of the tibiotalar joint in the early stance.The use of high-speed DFIS to quantify the movement of the tibiotalar and subtalar joint was critical to revealing the effects of RF S and FFS during running. 展开更多
关键词 Foot strike patterns High-speed dual fluoroscopic imaging system In vivo kinematics Running
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Exploration and Practice of the"One-Student-Two-Tutors"Community through Integrating"1+3 Teaching Resources"into Undergraduate Experimental Teaching
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作者 Yongming YANG Dongfang TU +6 位作者 Yan YU Shengwei YAO Wei ZHANG Shuangyuan WANG Pengyun DUAN Weiyu NI Wencui LIU 《Asian Agricultural Research》 2024年第11期49-53,共5页
This study closely follows the spirit of the first class undergraduate education action plan(2021-2025)of University of Shanghai for Science and Technology,combines with the national first-class undergraduate professi... This study closely follows the spirit of the first class undergraduate education action plan(2021-2025)of University of Shanghai for Science and Technology,combines with the national first-class undergraduate professional training plan of mechanical design and manufacturing and automation,and carries out the exploration and practice of"1+3 teaching resources"integrating into the"One-Student-Two-Tutors"community of undergraduate experimental teaching.On the basis of creating a good learning environment and creating an excellent learning platform,this paper studies the undergraduate experimental teaching of the trinity of"theoretical courses+experimental courses+innovation and entrepreneurship activities,discipline competitions,and scientific research project activities".This study has a certain reference value for colleges and universities to cultivate outstanding engineering talents with happy learning attitude,scientific research interest,practical ability and innovative ability. 展开更多
关键词 "1+3 teaching resources" "One-Student-Two-Tutors"community Undergraduate experimental teaching
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Reform of Hospitality English Teaching Based on the Educational Concept of Outcome-Based Education(OBE) 被引量:1
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作者 Chong Zhang 《Journal of Contemporary Educational Research》 2024年第1期58-64,共7页
The Outcome-Based Education(OBE)educational concept,proposed by renowned American educator Spady,aims to guide students in mastering learning laws and ultimately achieving expected learning outcomes.The application of... The Outcome-Based Education(OBE)educational concept,proposed by renowned American educator Spady,aims to guide students in mastering learning laws and ultimately achieving expected learning outcomes.The application of OBE educational concept in Hospitality English curriculum not only can effectively enhance the learning effect but also promote the reform of the Hospitality English curriculum,thus improving students’learning enthusiasm.Therefore,taking the Hospitality English curriculum as an example,this paper points out the existing problems in the teaching of this course and suggests the reform measures based on the OBE teaching concept,hoping to provide guidelines for related educational work. 展开更多
关键词 Outcome-Based Education(OBE)educational concept Hospitality English curriculum teaching reform Practical strategy
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