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Hydrocephalus Secondary to Intraventricular Myxopapillary Ependymoma: Case Report
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作者 Juan Carlos Ayala-Alvarez Onyekachi Emmanuel Anyagwa +8 位作者 Fátima Gabriela Macías-Ortiz Oluwatoyin Adalia Dairo Courtney Storm Truebody Reza Badrnejad Aishwarya Bhuta Shashwat Sandeep Phade Srushti Kishor Jamdar Mostafa Yassin Vismaja Vijayan 《World Journal of Neuroscience》 CAS 2024年第3期85-91,共7页
Ependymomas are a somewhat diverse category of glial tumors that often develop from the lining of the brain’s ventricles, or the spinal cord’s central canal. They make up 5% of all neuroepithelial tumors, 10% of pae... Ependymomas are a somewhat diverse category of glial tumors that often develop from the lining of the brain’s ventricles, or the spinal cord’s central canal. They make up 5% of all neuroepithelial tumors, 10% of paediatric brain tumors, and up to 33% of brain tumors in children under the age of three. Hydrocephalus is one of the complications, and it can be identified as progressive macrocephaly or increasing head circumference crossing percentiles, nausea, vomiting, poor appetite, irritability, and regression of developmental milestones. 展开更多
关键词 hydrocephalus Myxopapillary Ependymoma (MPE) PAEdiATRICS NEUROSURGERY GLIOMA Intracranial Hypertension
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Current research of idiopathic normal pressure hydrocephalus:Pathogenesis,diagnosis and treatment 被引量:1
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作者 Tetsuro Ishida Tomonori Murayama Seiju Kobayashi 《World Journal of Clinical Cases》 SCIE 2023年第16期3706-3713,共8页
Idiopathic normal pressure hydrocephalus(iNPH)is caused by impaired cerebrospinal fluid absorption in the elderly;it is a surgically treatable form of dementia.Gait disturbance,dementia,and urinary incontinence are th... Idiopathic normal pressure hydrocephalus(iNPH)is caused by impaired cerebrospinal fluid absorption in the elderly;it is a surgically treatable form of dementia.Gait disturbance,dementia,and urinary incontinence are the triad of signs for iNPH.In addition to these clinical findings,imaging studies show characteristic ventricular enlargement.High Evans Index and‘disproportionately enlarged subarachnoid hydrocephalus’are other well-known imaging findings of iNPH.If the tap test shows improved symptoms,shunt surgery is performed.The disease was first described by Hakim and Adams in 1965,followed by the publication of the first,second,and third editions of the guidelines in 2004,2012,and 2020,respectively.Recent studies signal the glymphatic system and classical cerebrospinal fluid(CSF)absorption from the dural lymphatics as aetiological mechanisms of CSF retention.Research is also underway on imaging test and biomarker developments for more precise diagnosis,shunting technique options with fewer sequelae and complications,and the influence of genetics.Particularly,the newly introduced‘suspected iNPH’in the third edition of the guidelines may be useful for earlier diagnosis.However,less well-studied areas remain,such as pharmacotherapy in non-operative indications and neurological findings other than the triadic signs.This review briefly presents previous research on these and future issues. 展开更多
关键词 REVIEW Idiopathic normal pressure hydrocephalus Treatable dementia Shunt surgery Drug therapy
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CT Profile of Hydrocephalus in Children at the Charles de Gaulle Pediatric Teaching Hospital in Ouagadougou
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作者 Soré Moussa Zanga Kisito Nagalo +4 位作者 Fadiilah Laetitia Nonkané Aïscha Madina Napon Ousséini Diallo Léonie Claudine Lougué/Sorgho Rabiou Cissé 《Open Journal of Radiology》 2023年第3期155-166,共12页
Aim of the Study: The aim is to analyse the epidemiological, clinical and CT aspects of hydrocephalus in children. Method: This was a cross-sectional descriptive study with retrospective collection from 1 June 2021 to... Aim of the Study: The aim is to analyse the epidemiological, clinical and CT aspects of hydrocephalus in children. Method: This was a cross-sectional descriptive study with retrospective collection from 1 June 2021 to 31 December 2022 within the radiology department of Charles De Gaulle Pediatric Teaching Hospital in Ouagadougou, Burkina Faso. The study included the records of patients with hydrocephalus who underwent cerebral computed tomography within this radiology department. Results: Hydrocephalus is due to a disorder of the hydrodynamics of the cerebrospinal fluid causing an increase in the volume allocated to this fluid in the brain and being accompanied by an increase in the pressure of this fluid. Its diagnosis is established by Doppler ultrasound or MRI prenatally, transfontanellar ultrasound in newborns and young children whose fontanel is permeable and by CT or MRI in older children, who can also determine the etiology. MRI remains an imaging technique that is less available and less accessible than CT in developing countries like ours. In Burkina Faso, MRI is only available in two private health facilities. The objective of this study was to describe the epidemiological, clinical and computed tomography aspects of hydrocephalus in children at the Charles de Gaulle pediatric teaching hospital in order to contribute to the diagnostic assessment and better management of this pathology. Over 19 months, 105 cases of hydrocephalus were recorded out of a total population of 115 children, or an average of 6 cases per month. The mean age was 17.52 months, with extremes of 03 days and 13 years, and the sex ratio was 1.38. Macrocrania, convulsions and psychomotor retardation were the main clinical signs, with rates of 49%, 34% and 30% respectively. On cerebral CT scan, hydrocephalus was triventricular (41.90%), tetraventricular (40%), and predominantly non-communicating (60%), with a mean Evans score of 0.53. The aetiologies were malformations in 34.28% of cases, tumours in 10.47% and infections in 5.71%. Among the malformations, Arnold Chiari II syndrome associated with spina bifida and Dandy Walker syndrome were the most common, accounting for 25% each. Tumour causes were dominated by craniopharyngioma and astrocytoma, each accounting for 27.30% of cases. Conclusion: The incidence of hydrocephalus was high in our study. In the absence of MRI (due to its unavailability and inaccessibility), CT revealed hydrocephalus that was predominantly tri- and tetraventricular, and predominantly non-communicating. 展开更多
关键词 hydrocephalus MALFORMATIONS CEREBRAL TOMOGRAPHY
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罕见抗-Di^(b)致严重胎儿新生儿溶血病的实验室检测与相关研究
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作者 廖志坚 贾双双 +5 位作者 温机智 莫春妍 邵媛 张润青 罗广平 姬艳丽 《中国输血杂志》 CAS 2024年第2期158-164,共7页
目的对1例高频抗体导致的胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)进行检测、鉴定及配血。方法对患儿进行新生儿溶血试验,对母亲进行血清学意外抗体鉴定,并对母亲红细胞进行常见高频抗原鉴定;对检出抗体进行... 目的对1例高频抗体导致的胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)进行检测、鉴定及配血。方法对患儿进行新生儿溶血试验,对母亲进行血清学意外抗体鉴定,并对母亲红细胞进行常见高频抗原鉴定;对检出抗体进行IgG分型检测,并用流式细胞术进行单核细胞体外吞噬致敏红细胞试验,以检测抗体相关的吞噬率;对患儿母亲、父亲及舅舅进行相关红细胞血型基因测序;利用稀释的母亲血浆和抗人球卡法,在献血者中进行大规模相合血液的筛选。结果产妇鉴定为Di(b-)稀有血型,产生了抗-Di b(效价512)并导致了严重的HDFN;抗-Di b亚型分型为IgG1和IgG2型,单核细胞体外吞噬效率为88.83%(74.7/84.09);产妇亲属中没有相合献血者,后续从5520名献血者中筛选到2例Di(b-)相合血液,患儿接收输血治疗后康复出院。后续在51334名献血者中筛查到17名Di(b-)献血者,该数据表明Di(b-)在广州地区献血者中的分布频率约为三千分之一(0.033%,17/51334)。结论综合利用血型血清学及分子生物学方法诊断了抗-Di b所致的严重HDFN,建立了1种有效大规模筛查Di(b-)稀有血型的方法并找到相合血液,为建立Di(b-)稀有血型库奠定了基础。 展开更多
关键词 抗-di b di(b-)稀有血型 胎儿新生儿溶血病
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4DI110型空压机的技术改造与操作优化
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作者 李强 《化工管理》 2024年第14期122-125,共4页
文章通过介绍新引进的4DI110型离心式空压机(以下简称“空压机”)试运行阶段开始以来的运行情况和气温变化对空压机出口流量造成的影响,分析空压机出口流量随气温变化而变化的规律,指出空压机防喘阀V3004阀不能自动调节出口压力,影响空... 文章通过介绍新引进的4DI110型离心式空压机(以下简称“空压机”)试运行阶段开始以来的运行情况和气温变化对空压机出口流量造成的影响,分析空压机出口流量随气温变化而变化的规律,指出空压机防喘阀V3004阀不能自动调节出口压力,影响空分装置工况的稳定。为实现空压机出口压力的稳定,对其防喘阀V3004阀采取增设自动旁路阀V3008阀的技术改造,同时优化和完善相关逻辑控制并阐述了空压机经技术改造后的操作优化和取得的实际效果。 展开更多
关键词 4di110型离心式空压机 逻辑控制 技术改造 操作优化
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Brucella meningoencephalitis with hydrocephalus masquerading as tuberculosis 被引量:2
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作者 Vishwanath Sathyanarayanan Bekur Ragini +1 位作者 Abdul Razak M Mukhya prana Prabhu 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第10期835-837,共3页
Neurobrucellosis is a rare form of localized brucellosis usually with no systemic manifestations. We report a rare case of brucellosis presenting as meningoencephalitis associated with hydrocephalus.This patient had a... Neurobrucellosis is a rare form of localized brucellosis usually with no systemic manifestations. We report a rare case of brucellosis presenting as meningoencephalitis associated with hydrocephalus.This patient had a lymphocytic predominant CSF and was initially treated with empirical anti tubercular therapy and steroids.A week later,when his CSF culture grew Brucella species,the treatment was changed to a combination of streptomycin,doxycycline and rifampicin and the patient improved with this therapy.This case illustrates the need to consider neurobrucellosis as a close differential diagnosis of neurotuberculosis in endemic areas when the patient presents with meningo encephalitis with lymphocytic CSF. 展开更多
关键词 NEUROBRUCELLOSIS MENINGOENCEPHALITIS hydrocephalus Tubercular MENINGITIS
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MODIFIED GRAEB CRITERIA FOR PREDICTING THE POST-HEMORRHAGIC HYDROCEPHALUS IN INTRAVENTRICULAR HEMORRHAGE 被引量:6
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作者 ZhiSong Qi-dongYang +1 位作者 Xiao-hongZi XuejunFan 《Chinese Medical Sciences Journal》 CAS CSCD 2004年第2期138-141,共4页
Objective To set up a new grading system of intraventricular hemorrhage (IVH) and determine the value of predicting the probability of post-hemorrhagic hydrocephalus (PHH) in IVH. Methods We first modified the Graeb c... Objective To set up a new grading system of intraventricular hemorrhage (IVH) and determine the value of predicting the probability of post-hemorrhagic hydrocephalus (PHH) in IVH. Methods We first modified the Graeb criteria, then compared the value of prediction for PHH assessed by the Graeb criteria with the modified Graeb criteria. One hundred and thirty one IVH patients were divided into two groups: the upper group (n=67) and the lower group (n=64). Gold standard of PHH was assessed by CT scan or by out-drainage. The diagno-stic parameters such as sensitivity (SE), specificity (SP) were analyzed. In the cutoff point of SE and SP curves, diagnostic efficiency (DE), and Kappa value (K) were analyzed. The probability of PHH was estimated by binary logistic regressions. Results In all ventricular group, to Graeb criteria in the cutoff point, SE, SP, and K was 0.78, 0.84, and 0.60; and to modified Graeb criteria SE, SP, and K was 0.90, 0.84, and 0.74 respectively. The probability of PHH from point of 3-12 was 0.011, 0.032, 0.085, 0.212, 0.435, 0.689, 0.865, 0.949, 0.981, and 0.994 respectively according to modified Graeb criteria. Conclusion The modified Graeb criteria combined with logistic regression were useful methods to assess the severity of IVH and to predict the probability of PHH in IVH. 展开更多
关键词 intracerebral hemorrhage intraventricular hemorrhage hydrocephalus PREdiCTION
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借助DIS实验突破教学难点——以“磁场对通电导线的作用力”为例
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作者 谭旭艳 吕兵 《实验教学与仪器》 2024年第2期18-19,共2页
教材中直接得出安培力的公式,该知识点难度较大,传统实验现象不够明显且只能定性探究,学生无法真正理解该物理规律和公式。传统实验加DIS实验可对物理规律进行定性和定量的探究,有利于学生物理学科核心素养的培养。
关键词 磁场 通电导线 安培力 diS实验 教学难点
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用DIS电磁定位魔板探究平抛运动的教学设计
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作者 王佳丽 张轶炳 《物理通报》 CAS 2024年第1期90-95,共6页
随着数字化信息系统在中学物理教学中的逐步融入,我国中学物理实验呈现智能化、现代化的发展趋势.以DIS电磁定位魔板为实验装置,通过科学探究的关键环节,设计探究平抛运动的教学流程.实践发现传感器实验也适合做科学探究,能够充分提升... 随着数字化信息系统在中学物理教学中的逐步融入,我国中学物理实验呈现智能化、现代化的发展趋势.以DIS电磁定位魔板为实验装置,通过科学探究的关键环节,设计探究平抛运动的教学流程.实践发现传感器实验也适合做科学探究,能够充分提升学生科学探究和推理论证的能力. 展开更多
关键词 diS电磁定位魔板 平抛运动 科学探究 教学设计
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城市轨道交通减振轨道DI型弹条断裂原因分析及治理效果
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作者 段勇奇 廖志军 +3 位作者 周波 陈凌志 王子毓 张明兰 《城市轨道交通研究》 北大核心 2024年第8期57-60,66,共5页
[目的]弹条是减振轨道扣件中的关键部件,其力学性能及承受疲劳载荷性能关系到城市轨道交通列车运行安全及轨道使用寿命。针对目前弹条失效破坏频发的情况,有必要对其断裂原因进行分析并制定合理治理措施。[方法]以某城市轨道交通线路某... [目的]弹条是减振轨道扣件中的关键部件,其力学性能及承受疲劳载荷性能关系到城市轨道交通列车运行安全及轨道使用寿命。针对目前弹条失效破坏频发的情况,有必要对其断裂原因进行分析并制定合理治理措施。[方法]以某城市轨道交通线路某区段出现弹条集中断裂的情况为依托,通过弹条断口分析确定弹条的断裂类型为疲劳断裂,通过分析弹条的化学成分和物理性能未发现异常状态,通过仿真分析和试验分析得到弹条的固有频率。结合弹条断裂区段轨道动态测试得到轨道和弹条的振动特性,由此确定轨道波磨可能是引起弹条出现反复断裂的主要原因。针对该原因制定了合理的治理措施,对治理前后的弹条断裂数量进行了统计。[结果及结论]钢轨打磨措施有效抑制了轨道波磨,大大减少了弹条断裂情况的发生,进一步佐证了轨道波磨是引起弹条断裂的主要原因。 展开更多
关键词 城市轨道交通 减振轨道 di型弹条 断裂原因 治理效果
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嗜热链球菌c-di-AMP合成酶的结构预测
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作者 范艺周 骆思羽 +3 位作者 朱浩伟 薛珍 艾连中 熊智强 《工业微生物》 CAS 2024年第1期171-176,共6页
作为一种新兴第二信使分子,c-di-AMP具有全局调控胞内渗透压平衡、DNA损伤和生物膜形成等生理功能。本实验室在实验前期筛选出了一株高产胞外多糖的嗜热链球菌菌株S-3,但未对其进行c-di-AMP信号通路研究。本研究在嗜热链球菌S-3全基因... 作为一种新兴第二信使分子,c-di-AMP具有全局调控胞内渗透压平衡、DNA损伤和生物膜形成等生理功能。本实验室在实验前期筛选出了一株高产胞外多糖的嗜热链球菌菌株S-3,但未对其进行c-di-AMP信号通路研究。本研究在嗜热链球菌S-3全基因组中筛选出c-di-AMP合成酶(StDAC),对其二级结构进行预测,结果显示St DAC二级结构包含42.98%α-螺旋、15.32%β-折叠和38.30%无规则卷曲。利用SWISS-MODEL和Modeller对StDAC进行单模板和多模板同源建模,由SWISS-MODEL建立的模型通过了Ramachandran、Errat和Verify-3D评估,表明其结构较为合理;而Modeller建立的模型仅通过了Ramachandran评估,总体结构评分较低。本研究预测的嗜热链球菌StDAC三维模型为解析其结构和功能奠定了基础。 展开更多
关键词 嗜热链球菌 c-di-AMP 生物信息学 二级结构 同源建模
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乳酸菌第二信使分子c-di-AMP研究进展
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作者 范艺周 李欢欢 +3 位作者 喻林兵 曹佳尧 艾连中 熊智强 《工业微生物》 CAS 2024年第2期79-84,共6页
微生物依赖信号识别和信号传递来感知并响应外界环境变化。c-di-AMP作为第二信使分子在信号传导过程中发挥着关键作用,其通过酶、转录调控因子和核糖开关等受体靶标来调控细胞生长、生物膜形成、K^(+)稳态、DNA完整性、细胞壁合成和脂... 微生物依赖信号识别和信号传递来感知并响应外界环境变化。c-di-AMP作为第二信使分子在信号传导过程中发挥着关键作用,其通过酶、转录调控因子和核糖开关等受体靶标来调控细胞生长、生物膜形成、K^(+)稳态、DNA完整性、细胞壁合成和脂肪酸合成等与生理功能相关的基因和蛋白的表达。尽管对于c-di-AMP代谢调控在枯草芽孢杆菌、单增李斯特氏菌和金黄色葡萄球菌等细菌中的研究较为深入,但对其在乳酸菌中的研究却相对较少。基于此,文章重点关注乳酸菌中cdi-AMP的代谢及其在K^(+)稳态和抑制甘氨酸甜菜碱转运中的信号传导作用;同时,通过总结现有研究中的乳酸菌c-di-AMP代谢调控,深化对乳酸菌第二信使分子信号调控的认知。 展开更多
关键词 乳酸菌 第二信使分子 环二腺苷酸
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Advanced diffusion-weighted magnetic resonance imaging in the evaluation of white matter axons in patients with idiopathic normal pressure hydrocephalus
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作者 Masaaki Hori Kouhei Kamiya Ryusuke Irie 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第12期1974-1975,共2页
With the increasing application of regenerative medicine in vivo,non-invasive and accurate methods for estimating the white matter axons in neuronal tissue have become increasingly important.As a non-invasive method f... With the increasing application of regenerative medicine in vivo,non-invasive and accurate methods for estimating the white matter axons in neuronal tissue have become increasingly important.As a non-invasive method for patients,magnetic resonance(MR)imaging has demonstrated potential as a promising tool for evaluating axons in vivo.In particular,diffusion-weighted MR imaging(d MRI)and its applications, 展开更多
关键词 Advanced diffusion-weighted magnetic white matter pressure hydrocephalus
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外卖包装材料对我国青年群体暴露DBP和DiBP的影响
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作者 沈昊阳 陈立波 +6 位作者 张颖 鲁新宇 吴倩霆 马康维 王欣仪 马静 高崇婧 《浙江万里学院学报》 2024年第4期81-89,共9页
青年群体是外卖食品最大的消费群体,外卖包装材料中的污染物对青年群体的危害不容忽视。文章分析了外卖包装材料对我国青年群体暴露邻苯二甲酸二正丁酯(DBP)和邻苯二甲酸二异丁酯(DiBP)的影响,结果表明,发泡聚苯乙烯(PS)餐盒中DBP和DiB... 青年群体是外卖食品最大的消费群体,外卖包装材料中的污染物对青年群体的危害不容忽视。文章分析了外卖包装材料对我国青年群体暴露邻苯二甲酸二正丁酯(DBP)和邻苯二甲酸二异丁酯(DiBP)的影响,结果表明,发泡聚苯乙烯(PS)餐盒中DBP和DiBP的浓度(2986.27 ng/g和1345.20 ng/g)显著高于聚丙烯(PP)餐盒、纸质餐盒和锡纸餐盒,青年人群使用PS餐盒暴露DBP和DiBP的暴露量约为使用纸质餐盒和锡纸餐盒的2~5倍,青年人群经外卖餐盒暴露DBP和DiBP的暴露量占经饮食途径暴露DBP和DiBP暴露总量的1.72%~9.49%,占体内DBP和DiBP暴露总量的0.09%~0.47%。外卖包装材料是青年人群暴露DBP和DiBP的重要来源之一。 展开更多
关键词 邻苯二甲酸二正丁酯 邻苯二甲酸二异丁酯 外卖包装材料 暴露
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DIS实验助力高中物理教学探究——以图象问题为例
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作者 刘勇 《中文科技期刊数据库(文摘版)教育》 2024年第8期0156-0159,共4页
实验探究在高中物理教学中扮演着十分重要的角色。在数字化信息系统(DIS)实验的帮助下,弥补了一些传统实验在定量探究上的局限,极大地提升了实验教学效率。这种创新的教学方式有助于培养学生的实验探究精神,让他们养成严谨对待实验结果... 实验探究在高中物理教学中扮演着十分重要的角色。在数字化信息系统(DIS)实验的帮助下,弥补了一些传统实验在定量探究上的局限,极大地提升了实验教学效率。这种创新的教学方式有助于培养学生的实验探究精神,让他们养成严谨对待实验结果并深入剖析数据的科学习惯。本文立足于教学实践,详细探讨了如何有效利用DIS实验助力高中物理教学探究。以"用DIS实验探索力的相互作用、探究向心力实验、验证动量定理的实验案例"为例,展示了DIS实验在课堂中的精准、直观以及实际操作价值。 展开更多
关键词 diS实验 高中物理 教学探究
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Early fault prediction and detection of hydrocephalus shunting system
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作者 Abdel Rahman Alkharabsheh Lina Momani +3 位作者 Waleed Al-Nuaimy Jafar Ababneh Tariq Alwada’n Abeer Hawatmeh 《Journal of Biomedical Science and Engineering》 2013年第3期280-290,共11页
Trends of various intracranial pressure (ICP) parameters for high pressure hydrocephalus patients are utilized to detect various shunt faults in their early stages, as well as, to monitor the effect of such faults on ... Trends of various intracranial pressure (ICP) parameters for high pressure hydrocephalus patients are utilized to detect various shunt faults in their early stages, as well as, to monitor the effect of such faults on shunt performance. A method was proposed to predict the time required for ICP to be abnormal and for the valve to reach full blockage condition. Furthermore, an auto valve schedule updating method is proposed and used to temporarily deal with detected faults until the patient is checked up by his/her physician. The proposed algorithms were evaluated using numerical simulation. 展开更多
关键词 hydrocephalus SHUNTS SHUNT Malfunctions FAULTS DETECTION
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基于核心素养的高中物理DIS实验 校本课程开发的实践研究 ——以“探究平抛运动的特点”为例 被引量:1
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作者 黄荣 《中学理科园地》 2024年第1期80-82,86,共4页
运用传感器和计算机技术的DIS实验,兼具精确测量数据和快速直观展示结果的特点,在教育信息化的大背景下,逐渐在高中物理教学中普及。文章以探究平抛运动的特点为例,借助DIS实验的优点进行校本课程的开发,实现对学生核心素养的补充培养... 运用传感器和计算机技术的DIS实验,兼具精确测量数据和快速直观展示结果的特点,在教育信息化的大背景下,逐渐在高中物理教学中普及。文章以探究平抛运动的特点为例,借助DIS实验的优点进行校本课程的开发,实现对学生核心素养的补充培养。通过教学过程中的实践和反思提出了基于学科核心素养应用DIS实验开发校本课程应注意的一些问题。 展开更多
关键词 diS实验 高中物理 平抛运动 核心素养
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城轨交通DI型弹条接触疲劳断裂机理研究
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作者 张帆 郭正扬 +2 位作者 王志强 王金朝 徐宁 《山西建筑》 2024年第8期142-144,共3页
以DI型弹条为研究对象,基于实验得到正常行车状态下弹条的频域特性,采用有限元仿真对弹条进行失效特性分析。研究表明,弹条的断裂为疲劳断裂,表面缺陷产生的应力集中是弹条发生疲劳断裂的主要原因;在正常行车条件下,弹条和钢轨均在360 H... 以DI型弹条为研究对象,基于实验得到正常行车状态下弹条的频域特性,采用有限元仿真对弹条进行失效特性分析。研究表明,弹条的断裂为疲劳断裂,表面缺陷产生的应力集中是弹条发生疲劳断裂的主要原因;在正常行车条件下,弹条和钢轨均在360 Hz和700 Hz附近产生峰值,其中钢轨的垂向及横向振动频谱变化趋势基本一致;弹条安装深度过大将导致弹条与铁垫板接触点产生一定应力集中,在长期强迫振动激励作用下弹条容易发生疲劳折断。 展开更多
关键词 di型弹条 疲劳断裂 频域特性 失效分析
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Surgical Treatment for Neonatal Hydrocephalus: Catheter-Based Cerebrospinal Fluid Diversion or Endoscopic Intervention?
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作者 Matthias Krause Christos P. Panteliadis +4 位作者 Christian Hagel Franz W. Hirsch Ulrich H. Thome Jürgen Meixensberger Ulf Nestler 《Open Journal of Modern Neurosurgery》 2018年第1期30-45,共16页
Neonatal hydrocephalus can arise from a multitude of disturbances, among them congenital aqueductal stenosis, myelomeningocele or posthemorrhagic complications in preterm infants. Diagnostic work-up comprises transfon... Neonatal hydrocephalus can arise from a multitude of disturbances, among them congenital aqueductal stenosis, myelomeningocele or posthemorrhagic complications in preterm infants. Diagnostic work-up comprises transfontanellar ultrasonography, T2 weighted MRI and clinical assessment for rare inherited syndromes. Classification of hydrocephalus and treatment guidelines is based on detailed consensus statements. The recent evidence favors catheter-based cerebrospinal fluid diversion in children below 6 months, but emerging techniques such as neuroendoscopic lavage carry the potential to lower shunt insertion rates. More long-term study results will be needed to allow for individualized, multidisciplinary decision making. This article gives an overview regarding contemporary pathophysiological concepts, the latest consensus statements and most recent technical developments. 展开更多
关键词 CEREBROSPINAL Fluid hydrocephalus NEONATE NEUROENDOSCOPY VP-Shunt
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First results of CO_(2) dispersion interferometer on EAST tokamak
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作者 刘郁阳 李维明 +7 位作者 姚远 张耀 张家敏 连辉 洪博 王守信 揭银先 刘海庆 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期76-82,共7页
A dispersion interferometer(DI)has been installed and operates on the Experimental Advanced Superconducting Tokamak(EAST).This DI system utilizes a continuous-wave 9.3μm CO_(2)laser source to measure line-averaged el... A dispersion interferometer(DI)has been installed and operates on the Experimental Advanced Superconducting Tokamak(EAST).This DI system utilizes a continuous-wave 9.3μm CO_(2)laser source to measure line-averaged electron densities accurately.In contrast to conventional interferometers,the DI does not require substantial vibration isolations or compensating systems to reduce the impact of vibrations in the optical path.It also employs a ratio of modulation amplitudes,ensuring it remains immune to the variations in detected intensities.Without a variation compensation system,the DI system on EAST reaches a density resolution of less than1.8×10^(-2)πrad and a temporal resolution of 20μs.The measurements made by the POlarimeterINTerferometer(POINT)system and the far-infrared hydrogen cyanide(HCN)interferometer are remarkably consistent with the DI’s results.The possibility of fringe jumps and the impact of refraction in high-density discharge can be significantly decreased using a shorter wavelength laser source.A rapid density change of 3×10^(19)m^(-3)during 0.15 s has been measured accurately in shot No.114755 of EAST.Additionally,the DI system demonstrates dependability and stability under 305 s long-pulse discharges in shot No.122054. 展开更多
关键词 dispersion interferometer(di) electron density plasma diagnostics Experimental Advanced Superconducting Tokamak(EAST)
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