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Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery
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作者 Xue-Jian Wang 《World Journal of Clinical Cases》 SCIE 2025年第3期20-23,共4页
The chronic occlusion of intracranial arteries generally has no or mild clinical symptoms,and the clinical symptoms of acute cerebral artery occlusion are mostly manifested as severe cerebral infarction symptoms,which... The chronic occlusion of intracranial arteries generally has no or mild clinical symptoms,and the clinical symptoms of acute cerebral artery occlusion are mostly manifested as severe cerebral infarction symptoms,which often make early diagnosis difficult,thus losing the best treatment opportunity.Once cerebral infarction occurs,the consequences are difficult to recover.This is also an important reason for the high misdiagnosis rate and mortality of this disease.In this paper,the characteristics of the disease were analyzed to provide clinical reference. 展开更多
关键词 Chronic occlusion Misdiagnose Arterial occlusion middle cerebral artery occlusion ANEURYSM
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In the Middle of Global Governance Indonesia is actively participating in global governance reform through the MIKTA middle power grouping
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作者 Ding Gong 《China Report ASEAN》 2024年第1期45-47,共3页
In March 2023,Indonesia took over the chairmanship of MIKTA from Turkiye,marking the second time Indonesia has served as the rotating chair of a global governance mechanism,following the Bali G20 Summit in 2022.
关键词 middle ROTATING participating
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The Impact of Sea Level Rise on Roadway Design and Evacuation Routes in Delaware
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作者 Jack Palevich Ardeshir Faghri Ahmet Karakurt 《American Journal of Climate Change》 2024年第1期69-82,共14页
As the global temperature continues to increase, the sea level continues to rise at a rapid rate that has never been seen before. This becomes an issue for many facets of life but one of the most impacted is the trans... As the global temperature continues to increase, the sea level continues to rise at a rapid rate that has never been seen before. This becomes an issue for many facets of life but one of the most impacted is the transportation infrastructure. Many people living in low elevation coastal areas can become trapped by flooding with no way in or out. With Delaware being a coastal state, this would affect a large portion of the population and will have detrimental effects over time if nothing is done to combat sea level rise. The issue with sea level rise in transportation is that once the roads become flooded, they become virtually unusable and detour routes would be needed. If all the roads in a coastal area were to be affected by sea level rise, the options for detours would become limited. This article looks at direct solutions to combat sea level rise and indirect solutions that would specifically help transportation infrastructure and evacuation routes in Delaware. There is not one solution that can fix every problem, so many solutions are laid out to see what is applicable to each affected area. Some solutions include defense structures that would be put close to the coast, raising the elevation of vulnerable roads throughout the state and including pumping stations to drain the water on the surface of the road. With an understanding of all these solutions around the world, the ultimate conclusion came in the form of a six-step plan that Delaware should take in order to best design against sea level rise in these coastal areas. 展开更多
关键词 Sea Level rise Roadway Design Evacuation Routes
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The Effects of Age and Ejaculatory Abstinence on Semen Quality and Reproductive Hormones in Africa and the Middle East
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作者 Lionel Wildy Moungala Opheelia Makoyo 《Advances in Reproductive Sciences》 CAS 2024年第2期98-115,共18页
The aim of this study was to retrospectively evaluate the effects of male age and ejaculatory abstinence on semen parameters and reproductive hormones among men residing in Africa and the Middle East. A total of 70,14... The aim of this study was to retrospectively evaluate the effects of male age and ejaculatory abstinence on semen parameters and reproductive hormones among men residing in Africa and the Middle East. A total of 70,142 semen analysis results were analysed and grouped according to the age intervals (16 - 20, 21 - 30, 31 - 40, 41 - 50, 51 - 60, >60) and ejaculatory abstinence (<2 days, 2 - 5 days and >5 days). Semen parameters i.e. volume, concentration, progressive motility, total progressively motile count, morphology, total normal sperm count, DNA fragmentation, viability, sORP, normed sORP were specifically evaluated. Additionally, for each age interval, reproductive hormones i.e. estradiol, luteinizing hormone, follicle stimulating hormone, testosterone and prolactin were evaluated. Semen volume, total progressively motile count, sperm morphology and total normal sperm count constantly decrease significantly after the age of 30 years. Sperm concentration started declining significantly after the age of 50 years. There was a constant age-  related increase in number of spermatozoa with damaged DNA. sORP constantly increased up to 60 years. Furthermore, constantage-related decreases in FSH, serum testosterone and prolact in were observed from patients aged between 16 years and 60 years. Semen volume, sperm concentration, progressive motility and normal morphology were significantly higher in patients having > 5 days of abstinence. Patients having > 5 days of abstinence had the lowest normed sORP. Male age significantly affects sperm parameters and reproductive hormones in fertile and infertile men residing in Africa and the Middle East. Prolonged abstinence days provides better semen quality. 展开更多
关键词 AFRICA middle East Reproductive Hormones Semen Quality
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Squamous Cell Carcinoma of the Middle Ear: Case Report and Literature Review
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作者 Mariam Harrak Khouloud Ziani +3 位作者 Madiha Chelakhi Othmane Saqri Nabila Sellal Mohamed El Hfid 《Journal of Cancer Therapy》 2024年第9期303-310,共8页
Malignant tumors originating from the middle ear are rare. The literature identifies chronic inflammation and Human Papillomavirus (HPV) infection as the most common risk factors. A CT scan to assess bony invasion and... Malignant tumors originating from the middle ear are rare. The literature identifies chronic inflammation and Human Papillomavirus (HPV) infection as the most common risk factors. A CT scan to assess bony invasion and an MRI to evaluate soft tissue involvement, depth of invasion, and perineural invasion, followed by a biopsy, are indispensable for diagnosis and treatment. There is no standard treatment for squamous cell carcinoma of the middle ear, however, most reported cases are treated with surgical resection followed by postoperative radiotherapy. Given the challenges of achieving complete surgical excision, radiotherapy plays a crucial role in controlling middle ear cancers, as demonstrated in our case. We present a case of squamous cell carcinoma of the middle ear in a 63-year-old female with a history of chronic suppurative otitis media. The patient underwent a right subtotal petrosectomy without lymph node dissection followed by concurrent chemoradiotherapy. At the one-year follow visit, no recurrence or metastasis was detected. 展开更多
关键词 Chronic Suppurative Otitis the middle Ear Squamous Cell Carcinoma SURGERY RADIOtheRAPY
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Age and geochemical evolution of granite magmatism in Olkhon region from Caledonian syncollisional ore-free granite to the rare metal granite and pegmatite of Middle Paleozoic intraplate setting
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作者 Viktor Antipin Valentina Makrygina +1 位作者 Larisa Kushch Nataliya Sheptyakova 《China Geology》 CAS CSCD 2024年第1期63-79,共17页
The detailed description of two granite complexes in the Olkhon subterrane is given.The Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon series.It includes migmatites,granite-gnei... The detailed description of two granite complexes in the Olkhon subterrane is given.The Early Paleozoic Sharanur complex was formed by granitization of gneisses of the Olkhon series.It includes migmatites,granite-gneisses,granites and pegmatites of normal alkalinity;they belong to the type of syncollisional granites.The Middle Paleozoic Aya granite complex includes mother Aya massif of amazonite-bearing granites and several types of rare-metal pegmatites.They have elevated alkalinity,low of Ba,Sr,and high LILE and HFSE elements contents.The Aya pegmatites lie in northwest cracks of stretching and associated with the rise of the territory under the influence of the North Asian plume.These cracks and pegmatites mark the beginning of a new intraplate geodynamic setting.Two geochemical types are distinguished among the pegmatites of this complex.These are amazonite pegmatites of Li-F type with Ta mineralization and complex type pegmatite with Be-Rb-Nb-Ta and Li-F mineralization(the Ilixin vein).The Tashkiney pegmatite vein is similar to Ilixin,but lies in the gneisses of the Olkhon series.It shows high concentrations of Be,Nb,Ta,as well as W,Sn,but lacks Li and F,due to a greater depth and higher temperature of the melt crystallization of this pegmatite. 展开更多
关键词 PEGMATITE Geochemistry Submantle plume MAGMATISM Caledonian collision middle Paleozoic intraplate setting Be-Rb-Nb-Ta-Li-F mineralization Olkhon region Russia
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Reference Interval of Thyroidal Function of Women in the Early,Middle and Late Pregnancy in Jingzhou City,Hubei Province
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作者 Hongying WU Kai DING 《Medicinal Plant》 2024年第5期1-3,共3页
[Objectives]To study the reference value of thyroid function in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City.[Methods]362 healthy women of childbearin... [Objectives]To study the reference value of thyroid function in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City.[Methods]362 healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)were selected as the study group,and 360 non-pregnant women were selected as the control group.Serum thyroid hormone levels in the two groups were detected,and the reference value was expressed as the median(M)and 95%confidence interval(CI).On this basis,the chart of changing trend of thyroid hormone in the early,middle and late pregnancy were plotted.[Results]Compared with the control group,FT3,TT4,TT3,FT4and TSH in the early,middle and late pregnancy were significantly different in the study group(P<0.05).In the study group,there were significant differences in the early,middle and late pregnancy(P<0.05).[Conclusions]This trend chart has certain reference value in the screening,diagnosis and treatment of thyroid diseases in healthy women of childbearing age during different pregnancies(early,middle and late pregnancy)in Jingzhou City of Hubei Province. 展开更多
关键词 EARLY middle and late pregnancy Thyroid function Reference value Thyroid hormone
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Relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine fetal distress
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作者 Ji Chen Fei-Xue Liu Rui-Xue Tao 《World Journal of Clinical Cases》 SCIE 2024年第16期2745-2750,共6页
BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that t... BACKGROUND By comprehensively analyzing the blood flow parameters of the umbilical and middle cerebral arteries,doctors can more accurately identify fetal intrauterine distress,as well as assess its severity,so that timely interventions can be implemented to safeguard the health and safety of the fetus.AIM To identify the relationship between ultrasound parameters of the umbilical and middle cerebral arteries and intrauterine distress.METHODS Clinical data of pregnant women admitted between January 2021 and January 2023 were collected and divided into the observation and control groups(n=50 each),according to the presence or absence of intrauterine distress.The ultrasound hemodynamic parameters of the uterine artery(UtA),fetal middle cerebral artery(MCA),and umbilical artery(UmA)were compared with neonatal outcomes and occurrence of intrauterine distress in the two groups.RESULTS Comparison of ultrasonic hemodynamic parameters,resistance index(RI),pulsatility index(PI),and systolic maximal blood flow velocity of UmA compared to diastolic blood flow velocity(S/D),revealed higher values of fetal MCA,PI,and S/D of UmA in pregnant women with UtA compared to controls(P<0.05),while there was no difference between the two groups in terms of RI(P<0.05)The incidence of a neonatal Apgar score of 8-10 points was lower in the observation group(66.7%)than in the control group(90.0%),and neonatal weight(2675.5±27.6 g)was lower than in the control group(3117.5±31.2 g).Further,cesarean section rate was higher in the observation group(70.0%)than in the control group(11.7%),and preterm labor rate was higher in the observation group(40.0%)than in the control group(10.0%).The incidence of fetal distress,neonatal growth restriction and neonatal asphyxia were also higher in the observation group(all P<0.05).CONCLUSION Fetal MCA,UmA,and maternal UtA hemodynamic abnormalities all develop in pregnant women with intrauterine distress during late pregnancy,which suggests that clinical attention should be paid to them,and monitoring should be strengthened to provide guidance for clinical intervention. 展开更多
关键词 Late pregnancy Fetal intrauterine distress Ultrasound blood flow parameters Uterine artery middle cerebral artery Umbilical artery
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Granulometric and Mineralogical Characterization of the Sands of the Middle Course of the Kasai River (Territory of Ilebo, Province of Kasai/DR Congo)
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作者 Lowny Trésor Madienga Kitshabi Ivon Ndala Tshiwisa +4 位作者 Modeste Kisangala Muke Thomas Kanika Mamena Dominique Wetshondo Osomba Emmanuel Cibambula Musau Adalbert-Jules Makutu Ma Ngwayaya 《Journal of Geoscience and Environment Protection》 2024年第7期50-71,共22页
The sand bars, in perpetual transformation, observable in the middle course of the Kasai river on the section between the city of Ilebo (pk605) to the confluence of the Loange river (pk525), pose enormous navigability... The sand bars, in perpetual transformation, observable in the middle course of the Kasai river on the section between the city of Ilebo (pk605) to the confluence of the Loange river (pk525), pose enormous navigability problems. This may be dependent on hydrosedimentological characteristics of the Kasai River. This abundance of sand thus conditions the morphology of the middle course of the Kasai River in the section under our study. It therefore constitutes sedimentary navigation obstacles. The objective of this study is the granulometric and mineralogical characterization of the bar sands of the Kasai River in this study section. Particle size analyzes reveal these are moderately well classified to well classified unimodal sands (Classification coefficient between 1.29 to 1.742) largely presenting grain size symmetry and rarely fine asymmetry (Asymmetry coefficient—Skewness between −0.197 to 0.069) with mesorkurtic and rarely leptokurtic and platykurtic acuity (Angulosity coefficient—Kurtosis between 0.814 to 1.323). All these parameters evolve in sawtooth patterns from upstream to downstream. And then, an automated mineralogical analysis of the sands of the Kasaï River using a Qemscan FEG Quanta 650 made it possible to determine a very varied mineralogical procession with a sawtooth evolution. It is largely dominated by quartz (between 93.73% and 99.07%), followed by calcite (0.01% - 2.66%), iron oxides (0.01% - 1.88%), orthoclase (0.04% - 0.99%), plagioclase (0.01% - 0.75%) and Kaolinite (0.18% - 0.71%). Finally, this mineralogical procession is characterized by a group of minerals which do not reach the threshold of 0.55% such as: illite, apatite, ilmenite, muscovite, chlorite, biotite, montmorillonite, rutile, pyrophyllite, siderite, zircon and dolomite. The evolution of the mineralogical procession of the sands of the bars is not as clear as in the case of particle size parameters. 展开更多
关键词 Characterization Granulometric MINERALOGICAL SANDS middle Course Kasai River
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The Association Between Daily Physical Activity and Risk of Hypertension in Middle-Aged and Older Adults:A Nationwide Cohort Study in China
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作者 Junhua Zhang Jie Rong +1 位作者 Hui Zhang Yongmei Yan 《Journal of Clinical and Nursing Research》 2024年第9期83-92,共10页
Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA a... Physical activity (PA) plays a key role in the treatment of hypertension, and moderate to vigorous PA has been documented to lower the risk of developing hypertension. However, dose-response relationships between PA and hypertension are not consistent, and little is known about this relationship within the Chinese middle-aged and older people. We investigated the relationship between PA and hypertension within this population using China Health and Nutrition Survey 1991-2015 data. Physical activity was expressed in terms of the metabolic equivalent task (MET) and participants were divided into groups according to quartiles, namely, Q1 (< 32.97 METs-h/w), Q2 (32.97-60.38 METs-h/ w), Q3 (60.38-98.95 METs-h/w), and Q4 (> 98.95 METs-h/w). Compared with the Q1 group, the odds ratio of risk with hypertension (95% CIs) after adjusting for confounding factors were 0.63 (0.35, 1.12), 0.49 (0.28, 0.86), and 0.62 (0.35, 1.09) for those in Q2, Q3, and Q4, respectively. Restricted cubic spline functions were used and a U-shaped relationship between physical activity and hypertension risk was found, indicative of an optimal level of physical activity, which was found to be 112 METs-h/w. Our data suggest maintenance of optimal levels of total daily physical activity may be important for preventing hypertension in Chinese adults over the age of 40. 展开更多
关键词 Physical activity HYPERTENSION middle age Older adults
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The Critical Role of Middle Leaders in Schools:Cultivating a Culture of Trust and Supporting Educational Reform
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作者 Xingyun Fang Jianli Wang 《Journal of Educational Theory and Management》 2024年第1期1-6,共6页
This research delves into the often-underappreciated role of middle leaders in educational organizations,highlighting their significance as the linchpins between senior leadership and classroom teachers.Utilizing qual... This research delves into the often-underappreciated role of middle leaders in educational organizations,highlighting their significance as the linchpins between senior leadership and classroom teachers.Utilizing qualitative research methods,the study investigates the multifaceted responsibilities,challenges,and contributions of middle leaders in schools.Findings indicate that middle leaders foster a culture of trust within the institution by providing mentorship and guidance to new teachers.They undertake substantial tasks,such as team coordination,grade direction,and student supervision,in addition to their teaching duties.Despite their pivotal role,middle leaders often face mounting pressures and heavy workloads.This research underscores the need to recognize and support middle leaders in educational settings,acknowledging their vital role in fostering cohesion and facilitating the implementation of educational reforms. 展开更多
关键词 middle leaders Educational leadership Trust culture
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A Discussion on the Issue of Excessive Academic Burden among Middle School Students
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作者 Pinghui Tu 《Journal of Contemporary Educational Research》 2024年第11期6-15,共10页
At present,the heavy academic workload of middle school students is a common problem,which is still questioned by parents,concerned by the government,and hotly debated by society.This paper summarizes the following ei... At present,the heavy academic workload of middle school students is a common problem,which is still questioned by parents,concerned by the government,and hotly debated by society.This paper summarizes the following eight aspects:the difficult content of subject courses,excessive class hours,heavy homework burden,complicated exams,overwhelming study materials,fierce subject competition,prevalent off-campus tutoring,and poor physical and mental health.Recognizing these problems can help to optimize the education and teaching environment and achieve a sustainable enrollment rate. 展开更多
关键词 middle school students Excessive academic burden DISCUSSION
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The Impact of Sports Games on the Psychological Health of Middle School Students
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作者 Zhuozhuo Xin Seong Pek Lim Haojun Zhao 《Journal of Contemporary Educational Research》 2024年第3期95-100,共6页
This study conducted a 16-week comparative experiment with 160 students from Jinan No.5 Middle School in Shandong Province as the experimental subjects.During the implementation of the experiment,the subjects were div... This study conducted a 16-week comparative experiment with 160 students from Jinan No.5 Middle School in Shandong Province as the experimental subjects.During the implementation of the experiment,the subjects were divided into two groups:an experimental group and a control group.The experimental group was subjected to physical exercise interventions using sports game teaching methods during physical education class,while the control group followed traditional physical education teaching methods.The results showed that the psychological health status of the students in the experimental group was significantly better than that of the control group after the experiment.The application of sports games helps to improve the psychological health of middle school students in the course of physical education,promoting a positive and forward direction in student psychology and is an effective means to enhance the psychological health level of middle school students. 展开更多
关键词 Sports games Physical education middle school students Psychological health
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An Investigation on the Influence of Middle School Students'Grammar Learning Self-efficacy on Their Learning Performance
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作者 Chen Zheng Ci Zhang 《教育技术与创新》 2024年第3期14-30,共17页
In middleschool English teaching,grammar instruction has always been an important and challenging aspect.Due to the strong influence of grammar explanation in Chinese,learning English grammar may be affected by negati... In middleschool English teaching,grammar instruction has always been an important and challenging aspect.Due to the strong influence of grammar explanation in Chinese,learning English grammar may be affected by negative transfer from their native language,which could pose certain obstacles to English acquisition.Self-efficacy,as a major emotional factor influencing learners'internal regulation strategies,has attracted wide attention from researchers both domestically and internationally for its impact on learning performance.High self-efficacy helps learners develop a more positive mindset towards learning,thereby contributing to improved learning performance.Therefore,this study focuses on investigating the relationship between grammatical self-efficacy and learning performance of English grammar among middle school students.This research contributes to a complementary understanding of grammatical self-efficacy among educators,enhancing their teaching skills,and effectively guiding students to learn English grammar with a more positive and healthy mindset,presenting a future grammar instruction in middle school English teaching. 展开更多
关键词 Grammatical self-efficacy English grammar Learning performance middle school students
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Integration of Mathematics History into Junior Middle School Education: A Pedagogical Approach to Enhance Mathematical Literacy
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作者 Cheng Cheng 《Journal of Contemporary Educational Research》 2024年第3期69-72,共4页
The integration of the history of mathematics into junior middle school mathematics education represents a significant focus of international research in mathematics and education.The mathematics curriculum standards ... The integration of the history of mathematics into junior middle school mathematics education represents a significant focus of international research in mathematics and education.The mathematics curriculum standards for compulsory education have emphasized the importance of incorporating the history of mathematics,aiming to gradually integrate it into the mathematics classroom.However,in the practical implementation of junior middle school mathematics education,the effective combination of the history of mathematics with teaching methodologies remains largely unexplored.This article explores the integration of junior middle school mathematics education and the history of mathematics,aiming to provide classroom teaching recommendations for teachers and promote the formation of students’mathematical literacy. 展开更多
关键词 History of mathematics Junior middle school mathematics education Teaching methodologies
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Influence of Particles on the Loading Capacity and the Temperature Rise of Water Film in Ultra-high Speed Hybrid Bearing 被引量:3
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作者 ZHU Aibin LI Pei +2 位作者 ZHANG Yefan CHEN Wei YUAN Xiaoyang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期541-548,共8页
Ultra-high speed machining technology enables high efficiency, high precision and high integrity of machined surface. Previous researches of hybrid bearing rarely consider influences of solid particles in lubricant an... Ultra-high speed machining technology enables high efficiency, high precision and high integrity of machined surface. Previous researches of hybrid bearing rarely consider influences of solid particles in lubricant and ultra-high speed of hybrid bearing, which cannot be ignored under the high speed and micro-space conditions of ultra-high speed water-lubricated hybrid bearing. Considering the impact of solid particles in lubricant, turbulence and temperature viscosity effects of lubricant, the influences of particles on pressure distribution, loading capacity and the temperature rise of the lubricant film with four-step-cavity ultra-high speed water-lubricated hybrid bearing are presented in the paper. The results show that loading capacity of the hybrid bearing can be affected by changing the viscosity of the lubricant, and large particles can improve the bearing loading capacity higher. The impact of water film temperature rise produced by solid particles in lubricant is related with particle diameter and minimum film thickness. Compared with the soft particles, hard particles cause the more increasing of water film temperature rise and loading capacity. When the speed of hybrid bearing increases, the impact of solid particles on hybrid bearing becomes increasingly apparent, especially for ultra-high speed water-lubricated hybrid bearing. This research presents influences of solid particles on the loading capacity and the temperature rise of water film in ultra-high speed hybrid bearings, the research conclusions provide a new method to evaluate the influence of solid particles in lubricant of ultra-high speed water-lubricated hybrid bearing, which is important to performance calculation of ultra-high speed hybrid bearings, design of filtration system, and safe operation of ultra-high speed hybrid bearings. 展开更多
关键词 hybrid bearing liquid-solid flow solid particles loading capacity temperature rise
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Farm Production Growth in the Upper and Middle Parts of the Yellow River Basin,China,During 1980-1999 被引量:2
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作者 LI Xiang-lian LUO Yu-zhou +2 位作者 GAO Qiong DONG Suo-cheng YANG Xiu-sheng 《Agricultural Sciences in China》 CAS CSCD 2008年第3期344-355,共12页
The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were emplo... The impact of inputs on farm production growth was evaluated by analyzing the economic data of the upper and middle parts of the Yellow River basin, China for the period of 1980-1999. Descriptive statistics were employed to characterize the temporal trends and spatial patterns in farm production and five pertinent inputs of cultivated cropland, irrigation ratio, agricultural labor, machinery power and chemical fertilizer. Stochastic frontier production function was applied to quantify the dependence of the farm production on these inputs. The growth of farm production was decomposed to reflect the contributions by input growths and change in total factor productivity.. The change in total factor productivity was further decomposed into the changes in technology and in technical efficiency. The gross value of farm production in the region of study increased by 1.6 fold during 1980-1999. Among the five selected farm inputs, machinery power and chemical fertilizer increased by 1.8 and 2.8 fold, respectively. The increases in cultivated cropland, irrigated cropland, and agricultural labor were all less than 0.16 fold. The growth in the farm production was primarily contributed by the increase in the total factor productivity during 1980-1985, and by input growths after 1985. More than 80% of the contributions by input growths were attributed to the increased application of fertilizer and machinery. In the change of total factor productivity, the technology change dominated over the technical efficiency change in the study period except in the period of 1985-1990, implying that institution and investment played important roles in farm production growth. There was a decreasing trend in the technical efficiency in the region of study, indicating a potential to increase farm production by improving the technical efficiency in farm activities. Given the limited natural resources in the basin, the results of this study suggested that, for a sustainable growth of farm production in the area, efforts should be directed to technology progress and improvement in technical efficiency in the use of available resources. 展开更多
关键词 farm production stochastic frontier production function total factor productivity upper and middle parts of the Yellow River basin
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The Last 15,000 Years: Climate-Controlled and “Rare-Event”-Triggered/Rise and Fall of Holocene Cultures in the Near/Middle East and in Central Europe—Evidence and Background 被引量:2
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作者 Werner Schneider Elias Salameh 《Open Journal of Geology》 2015年第11期743-769,共27页
Pushed by the results of a preceding publication on the possibly Quaternary Jebel Waqf as Suwwan Meteorite Crater, Jordan [5], where an amazing coincidence of Rapid Climate Changes (RCCs) with Rise and Fall of Neolith... Pushed by the results of a preceding publication on the possibly Quaternary Jebel Waqf as Suwwan Meteorite Crater, Jordan [5], where an amazing coincidence of Rapid Climate Changes (RCCs) with Rise and Fall of Neolithic and Bronze Age Cultures became evident for the Near/Middle East, this paper deals with the same subject, however, relating to the complete Holocene period in the same area and, additionally, in Central Europe as well. By application of modern climatic data [6] comprising isotope analysis (δ18O, 14C, 10Be), acid and aerosol events, and greenhouse gases (CO2, CH4) Greenland ice cores as well as other astro-/geophysical and geological parameters, an overwhelming coincidence/relation/interdependence of both natural and cultural evidences becomes obvious throughout the last 15,000 years across the Northern Hemisphere. Apart from solar output and other astrophysical processes, most important climate- and Earth-related parameters are Mega-Volcanism (i.e.Santorini Greece: ~3640 yr cal. B. P.), Impact Events (i.e. during Mesolithic: ~9600 yr cal. B. P), rapid oceanic current change (DO-Events), and Plate Tectonics (possibly Atlantis-Event: ~11,500 yr cal. B.P. = Pleistocene/Holocene boundary). The most essential parameter is a significant temperature change related to more or less restricted latitude realms of the Northern Hemisphere. Thus, glacier advance/retreat controls the mobility of peoples (i.e. Nations' Migration, Teutonic Empires) and the access to ore deposits (Au, Ag, Cu, Sn, Zn, Pb, Fe) located in Alpine Mountain Ranges (i.e. End-Neolithic, Early Bronze Age). Myths like the Gilgamesh Epos and John Apocalypse convincingly reveal realistic contents relating to natural hazards like tsunamis, impact and flooding events. They unmisunderstandably make obvious that Myths may provide valuable contributions, especially to Geosciences. Some of the controlling parameters interrelate with others or present a kind of hierarchy: Mega-Volcanism/impact events à ejecta à wildfires, heat storms à cosmic winter, sint winter à stop of photosynthesis à mass extinction environmental pollution à greenhouse effects. Significant events (21 cases in total) occurred on i.e. 展开更多
关键词 Climate RARE EVENTS Mega-Volcanism Impact-Events Comets Interdependence/Relationship Myths CULTURES HOLOCENE Near/middle East Central Europe
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New Discovery of Radiolarians in the Pomulong Mélange, Middle part of the Yarlung Zangbo Suture Zone, Tibet
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作者 SUN Qian JI Zhansheng +1 位作者 WU Guichun WAN Xiaoqiao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第4期1139-1141,共3页
Objective The Pomulong mélange was established in the regional geological survey of Lhaze County at the scale of 1:250000 by the Geological Survey Institute of Hubei Province.
关键词 middle RADIOLARIANS lange
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Numerical Simulation of the Influence of Mean Sea Level Rise on Typhoon Storm Surge in the East China Sea 被引量:3
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作者 高志刚 韩树宗 +2 位作者 刘克修 郑运霞 于华明 《Marine Science Bulletin》 CAS 2008年第2期36-49,共14页
In this paper, ECOMSED (Estuarine Coastal Ocean Model with sediment transport) model is employed to simulate storm surge process caused by typhoon passing across East China Sea in nearly years. Capability of ECOMSED... In this paper, ECOMSED (Estuarine Coastal Ocean Model with sediment transport) model is employed to simulate storm surge process caused by typhoon passing across East China Sea in nearly years. Capability of ECOMSED to simulate storm surge is validated by comparing model result with observed data. Sensitivity experiments are designed to study the influence of sea level rise on typhoon storm surge. Numerical experiment shows that influence of mean sea level rise on typhoon storm surge is non-uniform spatially and changes as typhoon process differs. Maybe fixed boundary method would weaken the influence of mean sea level rise on storm surge, and free boundary method is suggested for the succeeding study. 展开更多
关键词 Storm surge simulation ECOMSED model East China Sea sea level rise
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