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Epidemiology of Cardiovascular Mortality in Patients under 60 Years Old in a Cardiology Department in West Africa, Dakar-Senegal
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作者 Aliou Alassane Ngaide Ngone Diaba Gaye +5 位作者 Joseph Salvador Mingou Mame Diarra Sene Momar Dioum Mouhamadou Bamba Ndiaye Alassane Mbaye Abdoul Kane 《World Journal of Cardiovascular Diseases》 CAS 2024年第8期502-514,共13页
Background: Our study aimed to examine cardiovascular mortality within the working-age population, exploring epidemiological, clinical, and paraclinical features, complications, and identifying etiological factors lin... Background: Our study aimed to examine cardiovascular mortality within the working-age population, exploring epidemiological, clinical, and paraclinical features, complications, and identifying etiological factors linked to mortality. Methods: We conducted a descriptive and analytical retrospective study from September 2019 to August 2022 at the General Hospital Idrissa POUYE in Dakar, we reviewed all the medical records of patients from 15 to 60 years old who died while admitted in the cardiology department. Data collected were socioeconomic status, clinical history, type of cardiovascular disaese, length of hospitalization, circumstances and timing of death. The data were analyzed with R. Studio version 2022.12.0 + 353 and Excel 2019, with a P-value Results: The study included 73 patients, indicating a specific mortality rate of 8.8% and a proportional mortality of 39%. Predominantly male (sex ratio 1.2), the average age was 44. Key cardiovascular risk factors identified were sedentarism (76.7%), hypertension (28.8%), and smoking (21.9%). The leading cause for consultation was dyspnea (72.6%). Notable findings included a majority of patients presenting with general condition deterioration (90%) and cardiovascular collapse upon admission (23.3%). Physical exam revealed signs of heart failure in 63%. Echocardiography showed left ventricular ejection fraction impairment (81%) and pulmonary hypertension (78%). Immediate causes of death were primarily cardiogenic shock (45.2%) and septic shock (37%). The analytical study indicates that the data most closely associated with mortality were age, socio-economic level, ischemic heart disease (p = 0.034), rheumatic valvulopathies, pulmonary embolism (p = 0.034), hypertension (HTA) (p = 0.009), smoking (p = 0.011), diabetes (p = 0.011), dyslipidemias, prolonged bedrest (p = 0.001), morbid obesity (p = 0.001), and COVID-19 infection (p = 0.017). Conclusion: The prevalence of ischemic heart diseases, pulmonary embolisms, and valvulopathies in premature mortality statistics underscores the need for enhanced cardiovascular prevention efforts. 展开更多
关键词 Mortality under 60 Years CARDIOVASCULAR DAKAR
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Frequency of Rotavirus among under 5 Children Admitted to Wad Madani Pediatric Teaching Hospital with Diarrhea, Gezira State, Sudan (2021-2022)
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作者 Rehab Ibrahim Ali Babekir Adil Mergani Babiker Bakri Yosif Mohamed Nour 《Open Journal of Medical Microbiology》 2024年第3期206-214,共9页
Rotavirus is the leading cause of acute gastroenteritis and responsible for 20% of death in children under 5 years of age approximately 111 million episodes of gastroenteritis due to Rotavirus in under 5 children, whi... Rotavirus is the leading cause of acute gastroenteritis and responsible for 20% of death in children under 5 years of age approximately 111 million episodes of gastroenteritis due to Rotavirus in under 5 children, which result in 25 million visits to clinic, 2 million hospitalization and 352,000 - 592,000 deaths. Children in the poorest countries account 82% of rotaviruses death. Diarrhea disease are major cause of death and disease among children under five years, a child on average suffers 2 to 3 attacks of diarrhea every year. Stools samples were collected from 196 children suffering from diarrhea and were tested for rotaviruses by immune chromatography test antigen (ICT-Ag), ELISA and RT PCR The data were analyzed using statistical package for the Social Sciences (SPSS). The results showed that prevalence of rotavirus was 26/196 (13.3%) by ICT Ag and ELISA and confirmed by RT-PC R. 87.8% of the children were vaccinated by Rota vaccine, 70% of their mothers not using soap for cleaning the children and thought diarrhea not infectious disease and believed it was caused by teething. In conclusion there was a decrease in prevalence of diarrhea by Rotavirus due to insertion of Rota vaccine in routine vaccination, rotavirus infection mostly occurs in poor family that not able to provide safe water and due to poor sanitation and low education of mother beside that some children suffered from malnutrition, so it recommended to incorporate ELISA as a diagnostic tool in routine diagnosis of rotavirus among children suffered from gastroenteritis. 展开更多
关键词 DIARRHEA ROTAVIRUS under 5 Laboratory Diagnosis SUDAN
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Effect of a Nutrition Education Intervention on Food Safety Knowledge, Attitudes and Practices of Mothers of Children under 5 Years in the Peri-Urban Areas of Bobo-Dioulasso: Before and after Study
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作者 Alain Hien Jérome W. Somé +4 位作者 Olivier O. Sombié Isidore Traoré Augustin N. Zeba Georges Anicet Ouedraogo Roland Nâg-Tiero Meda 《Food and Nutrition Sciences》 CAS 2024年第5期401-420,共20页
Background: This study assessed the effect of a nutrition education intervention. This intervention aimed to improve the knowledge, attitudes, and practices of mothers on food safety in the peri-urban areas of Bobo-Di... Background: This study assessed the effect of a nutrition education intervention. This intervention aimed to improve the knowledge, attitudes, and practices of mothers on food safety in the peri-urban areas of Bobo-Dioulasso in Burkina Faso. Methods: A total of 243 mothers of children under 5 years in the peri-urban of Bobo-Dioulasso were administered the FAO questionnaire for food safety knowledge, attitudes, and practices assessment during two cross-sectional surveys, before and after the intervention, in January and October 2017. The intervention included two components consisting of a theoretical phase (counselling and discussion) and cooking demonstrations implemented for ten months. To account for the before-and-after design of the study, the McNemar’s test was used to assess the effect of the intervention on food safety KAP of mothers of children under 5 years. Results: The mean age of mothers was 29 ± 6.2 years and 50.6% of them were between 20 and 29 years old. One for knowledge (cooking thoroughly with, p-value = 0.0001) and another for attitudes (perceived benefits of reheating leftovers before eating them, p-value = 0.0001), significantly increased after the intervention. In terms of food safety practices, all the indicators (cleaning of dirty surfaces, plates and utensils and storage of perishable foods) significantly increased (all p = 0.0001 Conclusion: This study provided some evidence of an effective nutrition education intervention for improving maternal KAP on food safety for their child’s feeding. 展开更多
关键词 Nutrition Education Intervention KNOWLEDGE Attitudes and Practices Food Safety Mothers of Children under 5 Years Burkina Faso
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Additive manufacturing of magnesium and its alloys: process-formabilitymicrostructure-performance relationship and underlying mechanism 被引量:6
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作者 Shang Sui Shuai Guo +8 位作者 Dong Ma Can Guo Xiangquan Wu Zhongming Zhang Chunjie Xu Dan Shechtman Sergei Remennik Daniel Safranchik Rimma Lapovok 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第4期247-290,共44页
Magnesium and its alloys,as a promising class of materials,is popular in lightweight application and biomedical implants due to their low density and good biocompatibility.Additive manufacturing(AM)of Mg and its alloy... Magnesium and its alloys,as a promising class of materials,is popular in lightweight application and biomedical implants due to their low density and good biocompatibility.Additive manufacturing(AM)of Mg and its alloys is of growing interest in academia and industry.The domain-by-domain localized forming characteristics of AM leads to unique microstructures and performances of AM-process Mg and its alloys,which are different from those of traditionally manufactured counterparts.However,the intrinsic mechanisms still remain unclear and need to be in-depth explored.Therefore,this work aims to discuss and analyze the possible underlying mechanisms regarding defect appearance and elimination,microstructure formation and evolution,and performance improvement,based on presenting a comprehensive and systematic review on the relationship between process parameters,forming quality,microstructure characteristics and resultant performances.Lastly,some key perspectives requiring focus for further progression are highlighted to promote development of AM-processed Mg and its alloys and accelerate their industrialization. 展开更多
关键词 additive manufacturing magnesium alloys underlying mechanisms forming quality microstructure characteristics and properties
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Underlying mechanisms and clinical potential of circRNAs in glioblastoma
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作者 LEI ZHANG YUAN ZHANG +2 位作者 HUIJUAN GAO XIN LI PEIFENG LI 《Oncology Research》 SCIE 2023年第4期449-462,共14页
Glioblastoma(GBM)is the most malignant form of glioma and is difficult to diagnose,leading to high mortality rates.Circular RNAs(circRNAs)are noncoding RNAs with a covalently closed loop structure.CircRNAs are involve... Glioblastoma(GBM)is the most malignant form of glioma and is difficult to diagnose,leading to high mortality rates.Circular RNAs(circRNAs)are noncoding RNAs with a covalently closed loop structure.CircRNAs are involved in various pathological processes and have been revealed to be important regulators of GBM pathogenesis.CircRNAs exert their biological effects by 4 different mechanisms:serving as sponges of microRNAs(miRNAs),serving as sponges of RNA binding proteins(RBPs),modulating parental gene transcription,and encoding functional proteins.Among the 4 mechanisms,sponging miRNAs is predominant.Their good stability,broad distribution and high specificity make circRNAs promising biomarkers for GBM diagnosis.In this paper,we summarized the current understanding of the characteristics and action mechanisms of circRNAs,illustrated the underlying regulatory mechanisms of circRNAs in GBM progression and explored the possible diagnostic role of circRNAs in GBM. 展开更多
关键词 CircRNAs GBM underlying mechanisms Clinical value
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Constraints on rigid zones and other distinct layers at the top of the outer core using CMB underside reflected PKKP waves
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作者 Fenglin Niu Cindi Kelly Jianping Huang 《Earthquake Science》 CSCD 2012年第1期17-24,共8页
Clear PKKP, a P wave reflects off the core-mantle boundary on the core side, is recorded by the transcontinental USArray from two deep earthquakes occurred in South America and Tonga, and one intermediatedepth earthqu... Clear PKKP, a P wave reflects off the core-mantle boundary on the core side, is recorded by the transcontinental USArray from two deep earthquakes occurred in South America and Tonga, and one intermediatedepth earthquake in the Hindu Kush region. We compare the PKKP waveforms with the direct P waves to investigate the fine structures near the core-mantle boundary, with a primary focus on the core side. We find no evidence for the existence of a sedimentary layer of lighter elements with a thickness above a few hundreds of meters beneath the reflection points of the two deep events, which are located at the Ninety-East Ridge and South Africa. On the other hand the PKKP wave duration of the Hindu Kush event is almost twice as long as that of the P wave, suggesting that multiple reflections may be occurring at the core-mantle boundary located beneath the Antarctic, which is located inside the so-called tangent cylinder of the outer core. The tangent cylinder is an imaginary cylindrical region suggested by geodynamics studies, which has different flow pattern and may have a higher concentration in lighter elements as compared to the rest of the outer core. One possible explanation of the elongated PKKP is a thin distinct layer with a thickness of a few kilometers at the top of the outer core, suggesting that precipitation of lighter elements may occur at the core-mantle boundary. Our data also indicate an extremely low Qp of 312, approximately 40% of the PREM average (N780), within the large-scale low-velocity anomaly in the lowermost mantle beneath Pacific. 展开更多
关键词 PKKP underside reflection rigid zones under CMB USArray
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布鲁氏菌病患者外周血白细胞及血小板参数的变化及临床意义 被引量:1
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作者 乔坤艳 刘韦娜 +2 位作者 郑晓雅 苏瑞 杨悦杰 《天津医药》 CAS 2024年第4期391-396,共6页
目的 研究布鲁氏菌病患者外周血白细胞及血小板参数的变化及其特点,探讨其临床应用价值。方法 纳入确诊布鲁氏菌病的患者90例,其中急性期59例,慢性期31例,另外选取同期40例健康人群为健康对照组。收集患者的临床症状等基本资料;采用全... 目的 研究布鲁氏菌病患者外周血白细胞及血小板参数的变化及其特点,探讨其临床应用价值。方法 纳入确诊布鲁氏菌病的患者90例,其中急性期59例,慢性期31例,另外选取同期40例健康人群为健康对照组。收集患者的临床症状等基本资料;采用全自动血液分析仪检测各组外周血白细胞计数、淋巴细胞计数、中性粒细胞计数、单核细胞计数、血小板计数、平均血小板体积(MPV)、血小板分布宽度(PDW);采用流式细胞仪检测外周血CD3^(+)T、CD4^(+)T及CD8^(+)T细胞计数,计算患者的中性粒细胞/淋巴细胞比值(NLR)及血小板/淋巴细胞比值(PLR),分析各细胞参数的变化特点并分析各参数对布鲁氏菌病的临床诊断价值。结果 慢性期组的关节痛和脊柱炎占比高于急性期组(P<0.05);与健康对照组相比,急性期组的白细胞计数、中性粒细胞计数、血小板计数及NLR均降低,慢性期组MPV和PDW降低,而CD3^(+)T细胞计数和单核细胞计数升高(P<0.05)。有关节炎症状的急性期布病患者白细胞计数、淋巴细胞计数、CD3^(+)T细胞计数和CD8^(+)T细胞计数低于无关节炎的急性期布病患者,而PLR则升高(P<0.05)。受试者工作特征(ROC)曲线分析结果显示中性粒细胞计数和NLR水平对于急性期布鲁氏菌病的ROC曲线下面积(AUC)分别为0.780和0.717,而CD3^(+)T细胞计数对于诊断慢性期布鲁氏菌病的AUC为0.748。在急性期患者中,CD3^(+)T、CD8^(+)T细胞计数及PLR水平对诊断关节炎的AUC分别为0.779、0.768、0.722。结论 急性期和慢性期布鲁氏菌病患者外周血白细胞和血小板参数均有不同程度的改变,对于布鲁氏菌病的诊断以及急性期布病患者关节炎的诊断有一定的临床应用价值。 展开更多
关键词 布鲁杆菌病 白细胞计数 血小板计数 关节炎 曲线下面积
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Consumer Knowledge about Electric Buses in Underserved Communities in Huntsville, Alabama
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作者 Eyitayo Olaleye Jacob Oluwoye +2 位作者 Deden Rukmana Joyce Pressley Aschalew Kassu 《Journal of Power and Energy Engineering》 2022年第7期13-30,共18页
The major offshoot of innovation of electric vehicles (EVs) is sustainability. Given the prevailing challenges of carbon emissions from automobiles and the consequent effects on climate change, the introduction of EVs... The major offshoot of innovation of electric vehicles (EVs) is sustainability. Given the prevailing challenges of carbon emissions from automobiles and the consequent effects on climate change, the introduction of EVs is timely to serve as an effective mechanism for reversing global warming. However, knowledge of EVs is not well distributed among the general population. This study is therefore aimed to analyze the familiarity of Americans with the basic features of EVs. One hundred respondents were selected from two underserved communities in Huntsville, Alabama, using a simple sampling technique. Nonetheless, only 71 residents returned the filled questionnaires. Data were analyzed using frequency counts and descriptive statistics. Findings revealed that the respondents were generally aware of EVs, but EVs are not yet common on their roads. The respondents also signaled low preferences for EVs. The purchase price, charging stations, and limited supply are the candid explanations for why EVs are not a priority in the respondents’ choice of cars. To bolster peoples’ taste toward EVs, the study, therefore, concludes that government authorities and city planners should popularize incentives among the people in underserved communities. 展开更多
关键词 Electric Vehicles Consumer Knowledge Descriptive Statistics under-served Communities United States
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公共图书馆播客品牌构建与营销策略研究——以多伦多公共图书馆Shelve Under播客品牌为例
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作者 曾婕 《图书馆研究与工作》 2023年第1期68-72,86,共6页
播客是互联网时代的产物,自诞生之日起,经历了兴起、萎缩、停滞三个历史阶段,现又逐渐走入复苏时期。大数据技术的持续升级与快餐式阅读消费的广泛流行进一步突显了音频媒介可随性收听的优势,播客平台的发展迎来了新的机遇。文章详细阐... 播客是互联网时代的产物,自诞生之日起,经历了兴起、萎缩、停滞三个历史阶段,现又逐渐走入复苏时期。大数据技术的持续升级与快餐式阅读消费的广泛流行进一步突显了音频媒介可随性收听的优势,播客平台的发展迎来了新的机遇。文章详细阐述了播客的突出优势、国内发展现状及面临挑战等,对加拿大多伦多公共图书馆播客品牌Shelve Under进行深入挖掘,分析其品牌构建与营销特点,以期给国内公共图书馆创新音频服务提供参考,推动听力资源更好地融入大众的学习和生活。 展开更多
关键词 公共图书馆 播客 有声阅读 Shelve under 品牌构建 多伦多
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The Effect of the COVID-19 Pandemic on Health Service Accessibility for Children under 5 in the Mayo-Tsanaga and Logone & Chari Departments, Far North Cameroon
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作者 Ulrich Dama Desire Tchoffo +5 位作者 Jean Ndibi Abanda François Anicet Onana Akoa Alphonse Tedonge Asobochia Melkior Fobasso Dzeuta Aureol-Le-Rocher Ngako Njiacheu Pierre Yassa Yoniene 《Health》 2023年第10期1047-1058,共12页
Context/objectives: The COVID-19 pandemic has disrupted all programs, potentially impacting access to health services for children under 5 years old. The Far North of Cameroon is one of the northern regions with a pre... Context/objectives: The COVID-19 pandemic has disrupted all programs, potentially impacting access to health services for children under 5 years old. The Far North of Cameroon is one of the northern regions with a prevalence of malnourished children ranging from 5% to 10%. Due to the barrier measures implemented to combat the pandemic, many parents are reluctant to take their children to healthcare facilities. Some of these children were benefiting from the Ambulatory Care Center (ACC) program prior to the COVID-19 outbreak. The main objective of this research is to assess the impact of COVID-19 on access to health services for children under 5 in the Mayo Tsanaga (MT) and Logone & Chari (LC) departments. The implementation of barrier measures could significantly increase the risk of malnutrition among children under 5 years old. Method: A cross-sectional analytical study was conducted in the MT and LC departments, employing both retrospective and prospective approaches. Data was collected through questionnaire, interview guide and a review of existing data prior to the pandemic (DHIS 2). Kobo Collect software was used for data collection, and R software was used for analysis. Results: Children who benefitted from the ACC program during the COVID-19 period were found to have a lower prevalence of malnutrition compared to those who did not benefit (OR: 0.09, CI {0.0 - 0.44}). Conclusion: COVID-19 has led to a decrease in the utilization of health facilities in both departments of the study, resulting in an increase in health issues such as malnutrition among children under 5 years old. Various policies have been implemented to improve attendance at health facilities. 展开更多
关键词 COVID-19 Impact HEALTH Child under 5 Far North Cameroon
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Raw Gangue Filling Mining under Construction —A Case Study in China 被引量:1
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作者 Daqing Li Changxiang Wang +4 位作者 Jinjie Xiao Wei Lu Baoliang Zhang Zongkai Li Xiaozhang Tong 《Engineering(科研)》 CAS 2023年第3期176-195,共20页
In order to recover the strip pillar coal resources, reduce the amount of gangue mountain and realize remediation of the goaf environment in the old mining area, the raw gangue filling mining technology was proposed. ... In order to recover the strip pillar coal resources, reduce the amount of gangue mountain and realize remediation of the goaf environment in the old mining area, the raw gangue filling mining technology was proposed. According to the previous practical experience, the feasibility of the implementation of raw gangue filling mining technology in the coal-pressed area was analyzed. Through the filling gangue compaction test, the deformation under different loading stages was obtained. Further, a reasonable prediction of the deformation beyond the experimental limited loading load was made based on the experimental results. Through the deformation source analysis of the whole process of gangue filling, the key factors for controlling deformation before, during, and after filling were determined. Additionally, the proportion of deformation during different stages was quantified. Considering the protection of surface buildings, mining fullness of the working face and mining technology, the production parameters of 1209 and 1210 filling working faces were preliminarily determined. Through numerical simulation, the rationality of mining scheme was verified. Based on the practice of 1209 working face and the key factors to control the deformation of gangue filling, the mining system and process in 1210 working face were optimized. According to the measured surface rock movement, raw gangue filling mining technology can meet the requirements of surface building protection level. Especially, this paper provides a method to quantitatively calculate the equivalent mining height (EMH) of raw gangue filling and its mining deformation, which has reference significance for old mining areas. 展开更多
关键词 Coal Resource Recovery under Construction Raw Gangue Filling Mining Principle of Space-Time Control Filling System and Process Innovation
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发展性照护下的多维度干预对喂养不耐受新生儿生长发育的影响 被引量:1
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作者 吴宏丽 李丹 +4 位作者 刘琦 李霜霜 张晓婷 曾佳丽 周旋 《临床护理杂志》 2024年第1期31-33,共3页
目的探讨发展性照护下的多维度干预对喂养不耐受新生儿生长发育的影响。方法选择2020年10月-2022年10月我院收治的喂养不耐受新生儿90例作为研究对象,按随机数字表法分为对照组和观察组,各45例。对照组给予常规护理干预,观察组给予发展... 目的探讨发展性照护下的多维度干预对喂养不耐受新生儿生长发育的影响。方法选择2020年10月-2022年10月我院收治的喂养不耐受新生儿90例作为研究对象,按随机数字表法分为对照组和观察组,各45例。对照组给予常规护理干预,观察组给予发展性照护下的多维度干预,两组持续干预3个月。比较两组指标恢复时间(达到喂养耐受时间、达到肠道营养时间以及鼻胃管留置时间)、生长发育(体重、头围、身长)及护理不良事件发生率。结果观察组干预后达到喂养耐受时间、达到肠道营养时间以及鼻胃管留置时间均短于对照组(P<0.05);观察组干预后体重、头围及身长均大于对照组(P<0.05);观察组护理不良事件发生率低于对照组(P<0.05)。结论发展性照护下的多维度干预可有效缩短喂养不耐受新生儿指标达标时间,促进生长发育,降低护理不良事件的发生。 展开更多
关键词 喂养不耐受 新生儿生长发育 发展性照护下的多维度干预
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王洼煤矿水库坝体下工作面安全开采高度研究 被引量:1
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作者 杨涛 张一铭 +7 位作者 张杰 林海飞 闫医慧 张建辰 马海虎 孙建平 庞海波 武浩昊 《西安科技大学学报》 CAS 北大核心 2024年第1期43-53,共11页
为解决水库坝体下开采安全性,提高煤炭资源回收率,以王洼煤矿水库坝体下110505工作面为研究背景,通过物理仿真模拟、数值模拟及理论分析等方法对覆岩裂隙发育规律及导水裂隙带高度展开研究。为避免矿井开采对地表水坝与水体破坏,针对导... 为解决水库坝体下开采安全性,提高煤炭资源回收率,以王洼煤矿水库坝体下110505工作面为研究背景,通过物理仿真模拟、数值模拟及理论分析等方法对覆岩裂隙发育规律及导水裂隙带高度展开研究。为避免矿井开采对地表水坝与水体破坏,针对导水裂隙带高度分析结果,提出了110505工作面限高开采方案。结果表明:工作面开采后地表形成“凹”型盆地,并产生拉伸裂隙,致使地表水位下降78%;现场实测导水裂隙高度为170.76 m,物理仿真模拟试验、数值计算、传统经验公式得出三者的导水裂隙带高度分别为162,164 m和120.57 m;方差修正系数对经验公式做出修正后,反推出限高开采的安全开采高度为2.6 m。研究揭示了工作面覆岩导水裂隙带高度发育规律及水库水体受采动影响的规律,为王洼煤矿后续此类条件下安全措施的制定提供了依据。 展开更多
关键词 水库下采煤 高强度开采 绿色开采 物理仿真 导水裂隙带
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周边眼偏位空孔爆破设计优化研究与应用 被引量:1
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作者 余绍山 王薇 李姚伟奇 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第4期1509-1520,共12页
依据已有研究对空孔效应和设置空孔时裂纹扩展规律进行探讨,发现空孔有利于裂纹贯通,对提升爆破效果有一定帮助,但也发现传统的直线型空孔布置会导致裂纹偏向,即在空孔附近转向、偏离原发展路径,影响原设计开挖轮廓。若设置偏位空孔,则... 依据已有研究对空孔效应和设置空孔时裂纹扩展规律进行探讨,发现空孔有利于裂纹贯通,对提升爆破效果有一定帮助,但也发现传统的直线型空孔布置会导致裂纹偏向,即在空孔附近转向、偏离原发展路径,影响原设计开挖轮廓。若设置偏位空孔,则可充分利用空孔效应及导向作用以提高开挖质量。对于偏位空孔在爆破中的效应,采用数值模拟研究了不同炮孔间距、空孔偏位角下的裂纹扩展规律和炮孔间贯通情况,探讨了最优偏位角度设计,并根据模拟结果对现场爆破方案进行优化,研究实际应用效果。研究结果表明:偏位空孔对爆生裂纹具有较直线空孔更明显的导向作用,主要表现在爆生裂纹尖端向空孔本身发展或被空孔裂纹引导偏向、最终主裂纹与空孔连通或在空孔范围之外主裂纹相贯通,更利于炮孔主裂纹扩展与贯通;通过提取模拟结果并测量裂纹范围,对于孔间距在60 cm及以下时,适用于周边眼爆破设计的最优偏位角为15°,在此情况下炮孔连线方向形成了与孔心连线相平行的裂纹,能显著提升贯通效果;对于优化后的福厦铁路某隧道爆破施工方案,通过振速监测及超欠挖断面扫描分析,发现周边眼起爆引起的爆破振速降低了超过50%,超欠挖值也由平均25 cm降低至15 cm以内,整体应用效果良好。该项研究可为隧道爆破减振及超欠挖控制研究提供一定参考。 展开更多
关键词 光面爆破 周边眼 偏位空孔 爆破振速 超欠挖控制
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电视胸腔镜下纵膈肿瘤切除围术期护理敏感指标体系的构建 被引量:1
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作者 刘霞 杨洋 邹凤宇 《护理研究》 北大核心 2024年第3期414-419,共6页
目的:构建电视胸腔镜下纵膈肿瘤切除围术期护理敏感指标体系,旨在为促进医院专科护理质量的提升提供参考。方法:以“结构-过程-结果”三维质量评价模型为基础框架,通过文献回顾、半结构式访谈和院内专家会议法,初步拟定电视胸腔镜下纵... 目的:构建电视胸腔镜下纵膈肿瘤切除围术期护理敏感指标体系,旨在为促进医院专科护理质量的提升提供参考。方法:以“结构-过程-结果”三维质量评价模型为基础框架,通过文献回顾、半结构式访谈和院内专家会议法,初步拟定电视胸腔镜下纵膈肿瘤切除围术期护理质量敏感指标体系,采用德菲尔函询法修改与论证,采用层次分析法确定权重。结果:2轮专家函询问卷的回收率分别为85.71%和100.00%,第2轮函询专家的专家权威系数(Cr)为0.897,指标的重要性均分为4.23~5.00分,变异系数(CV)为0.000~0.147;2轮函询的肯德尔协调系数分别为0.714和0.825(P<0.05)。构建的电视胸腔镜下纵膈肿瘤切除围术期护理敏感指标体系包括3个一级指标、8个二级指标、46个三级指标。结论:构建的电视胸腔镜下纵膈肿瘤切除围术期护理敏感指标体系科学、可靠,筛选出的评价指标可系统地为胸外科专科护理质量的持续改进提供依据。 展开更多
关键词 电视胸腔镜下纵膈肿瘤切除术 护理质量 德尔菲专家函询法 敏感性指标
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讲好中国教育故事 服务人类教育发展——专访上海师范大学张民选教授 被引量:1
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作者 张民选 孔令帅 舒美豪 《教师教育学报》 2024年第1期1-9,共9页
张民选教授一直致力于讲好中国教育故事、服务人类教育发展的崇高事业。为了贯彻联合国提出的教育可持续发展理念、响应国家参与全球教育治理倡议、推动上海全球城市建设计划实施,张民选教授带领团队建立了联合国教科文组织教师教育中... 张民选教授一直致力于讲好中国教育故事、服务人类教育发展的崇高事业。为了贯彻联合国提出的教育可持续发展理念、响应国家参与全球教育治理倡议、推动上海全球城市建设计划实施,张民选教授带领团队建立了联合国教科文组织教师教育中心——现已发展成为重要的国际教育经验交流平台。张民选教授重点论述了“为什么要讲好故事”“如何吸引别人来听故事”“讲什么故事”“怎么讲故事”和“谁来讲故事”等5个问题,并主张中国要积极展现自己的教育成就,要在国际事务中增强教育影响力。张民选教授还总结概括了中国教育成就背后的核心教育经验,介绍了其他国家的教育发展需求,并倡导全世界的教育工作者共同讲述中国教育故事。张民选教授认为,要在讲好中国教育故事的过程中全面客观认识中国与世界,各国要在相互借鉴先进教育经验基础上实现共同进步。张民选教授指出,数字技术为教育带来了新的挑战和机遇,教育工作者要积极探索数字时代育人新途径。为此,教师要充分发挥数字技术优势来提高教学质量,如为学生整合多种教育资源、提供社会和情感支持、开展有前瞻性的指导等。张民选教授向广大青年学者寄语:要充分发挥自身优势深入文献研究,在教育实践中总结有价值的教育经验;要拥有宽广胸怀,以传播中国优秀教育经验与服务全球教育发展为己任。 展开更多
关键词 中国故事 教育故事 联合国教科文组织教师教育中心 人类教育
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经皮冠状动脉腔内冲击波球囊导管成形术治疗支架膨胀不全2例
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作者 张明多 高秉钰 +3 位作者 田晋帆 张闽 葛长江 宋现涛 《中国介入心脏病学杂志》 CSCD 2024年第4期228-231,共4页
钙化病变增加了冠心病介入治疗的难度,增加了围术期及长期并发症风险,钙化病变的预处理非常重要,经皮冠状动脉腔内冲击波球囊导管成形术(IVL)在钙化病变中使用越来越多,众多临床试验证明了其对钙化病变的有效性和安全性。支架膨胀不全... 钙化病变增加了冠心病介入治疗的难度,增加了围术期及长期并发症风险,钙化病变的预处理非常重要,经皮冠状动脉腔内冲击波球囊导管成形术(IVL)在钙化病变中使用越来越多,众多临床试验证明了其对钙化病变的有效性和安全性。支架膨胀不全是支架内血栓形成和支架内再狭窄的重要危险因素,增加并发症发生率,目前对于钙化病变导致的支架膨胀不全的处理并无有效应对策略,也无明确的相关共识或指南。关于IVL治疗支架膨胀不全报道较少,且多为个案报道、小样本研究。本文报道了2例患者,支架置入后发现膨胀不全,采用IVL进行处理,取得较好效果。 展开更多
关键词 钙化 冲击波球囊 支架膨胀不全
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基于改进反步滑模控制算法的拖轮自主靠泊控制 被引量:1
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作者 刘佳仑 董智霖 +2 位作者 李诗杰 游旭 胡英俊 《中国舰船研究》 CSCD 北大核心 2024年第1期119-127,共9页
[目的]针对拖轮的自主靠泊控制问题,研究基于虚拟船领导的目标跟踪控制策略在拖轮自主靠泊中的应用。[方法]首先,将拖轮的自主靠泊过程转变为虚拟拖轮和实际拖轮的目标跟踪控制过程;然后,设计靠泊系统的运动学模型,考虑靠泊场景中的特... [目的]针对拖轮的自主靠泊控制问题,研究基于虚拟船领导的目标跟踪控制策略在拖轮自主靠泊中的应用。[方法]首先,将拖轮的自主靠泊过程转变为虚拟拖轮和实际拖轮的目标跟踪控制过程;然后,设计靠泊系统的运动学模型,考虑靠泊场景中的特殊环境干扰,使用反步法和滑模控制法(SMC)设计全回转尾推进拖轮的自主靠泊控制器,提供了3种不同的滑模面设计并使用李雅普诺夫函数进行稳定性验证;最后,采用仿真实验的方式,通过靠泊轨迹、速度误差和距离误差来对控制的效果进行验证。[结果]仿真实验结果表明,设计的拖轮自主靠泊控制策略以及控制器在拖轮自主靠泊场景中具有较好的效果,面对系统的不确定干扰有较好的表现。[结论]该控制策略以及靠泊控制器的适用性以及鲁棒性较好,以全新的角度实现了拖轮自主靠泊控制,为后续拖轮的靠泊控制研究提供了新的方向。 展开更多
关键词 欠驱动拖轮 自主靠泊 目标跟踪控制 反步法 滑模控制
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我国设施园艺病虫害发生特点与绿色防控策略
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作者 吴圣勇 张梦迪 +11 位作者 徐进 王恩东 崔丽 雷仲仁 史晓斌 谢学文 王少丽 王甦 魏书军 马中正 何莉梅 高玉林 《中国生物防治学报》 CSCD 北大核心 2024年第5期1169-1180,共12页
我国设施园艺发展迅速,对促进农业现代化、乡村振兴和都市农业发展具有重要作用。本文结合我国设施园艺产业的发展现状,总结设施环境下病虫害发生特点,并从农业防治、物理防治、生物防治、生态调控、生物技术和科学用药等方面概述了病... 我国设施园艺发展迅速,对促进农业现代化、乡村振兴和都市农业发展具有重要作用。本文结合我国设施园艺产业的发展现状,总结设施环境下病虫害发生特点,并从农业防治、物理防治、生物防治、生态调控、生物技术和科学用药等方面概述了病虫害防治技术,最后对设施园艺病虫害防治提出建议,以期为我国设施园艺的健康可持续发展提供参考。 展开更多
关键词 园艺产业 保护地栽培 病虫害 绿色防控
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Underwater Inhomogeneous Light Field Based on Improved Convolutional Neural Net Fish Image Recognition
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作者 Kai Liu Siyu Wang +1 位作者 Yadong Wu Weihan Zhang 《Open Journal of Applied Sciences》 2023年第7期1079-1095,共17页
In this paper, artificial intelligence image recognition technology is used to improve the recognition rate of individual domestic fish and reduce the recognition time, aiming at the problem that it is difficult to ea... In this paper, artificial intelligence image recognition technology is used to improve the recognition rate of individual domestic fish and reduce the recognition time, aiming at the problem that it is difficult to easily observe the species and growth of domestic fish in the underwater non-uniform light field environment. First, starting from the image data collected by polarizing imaging technology, this paper uses subpixel convolution reconstruction to enhance the image, uses image translation and fill technology to build the family fish database, builds the Adam-Dropout-CNN (A-D-CNN) network model, and its convolution kernel size is 3 × 3. The maximum pooling was used for downsampling, and the discarding operation was added after the full connection layer to avoid the phenomenon of network overfitting. The adaptive motion estimation algorithm was used to solve the gradient sparse problem. The experiment shows that the recognition rate of A-D-CNN is 96.97% when the model is trained under the domestic fish image database, which solves the problem of low recognition rate and slow recognition speed of domestic fish in non-uniform light field. 展开更多
关键词 Heterogeneous Light Field under Water CNN Image Recognition
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