scholarly journals The Vulnerability of Vessels Involved in the Role of Embolism and Hypoperfusion in the Mechanisms of Ischemic Cerebrovascular Diseases

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Yong Peng Yu ◽  
Lan Tan
Keyword(s):  
Cerebral Infarction ◽  
Dominant Role ◽  
Cerebrovascular Diseases ◽  
Effective Care ◽  
Cerebrovascular Events ◽  
Accurate Definition ◽  
Ischemic Cerebrovascular Diseases ◽  
Vascular Stenosis

Accurate definition and better understanding of the mechanisms of stroke are crucial as this will guide the effective care and therapy. In this paper, we review the previous basic and clinical researches on the causes or mechanisms of ischemic cerebrovascular diseases (ICVD) and interpret the correlation between embolism and hypoperfusion based on vascular stenosis and arterial intimal lesions. It was suggested that if there is no embolus (dynamic or in situ emboli), there might be no cerebral infarction. Three kinds of different clinical outcomes of TIA were theoretically interpreted based on its mechanisms. We suppose that there is a correlation between embolism and hypoperfusion, and which mechanisms (hypoperfusion or hypoperfusion induced microemboli) playing the dominant role in each type of ICVD depends on the unique background of arterial intimal lesions (the vulnerability of vessels). That is to say, the vulnerability of vessels is involved in the role of embolism and hypoperfusion in the mechanisms of ischemic cerebrovascular diseases. This inference might enrich and provide better understandings for the underlying etiologies of ischemic cerebrovascular events.

Whole-Brain Volume CT Angiography can Effectively Detect Early Ischemic Cerebrovascular Diseases

2021 ◽  
Vol 17 ◽  
Author(s):  
Shi-Feng Xiang ◽  
Jun-Tao Li ◽  
Su-Jun Yang ◽  
Fang-Fang Ding ◽  
Wei-Wei Wang ◽  
...  
Keyword(s):  
Ct Scan ◽  
Ct Angiography ◽  
Brain Volume ◽  
Ct Perfusion ◽  
Cerebrovascular Diseases ◽  
Whole Brain ◽  
Ischemic Cerebrovascular Diseases ◽  
Vascular Stenosis ◽  
Cerebral Ischemic ◽  
Volume Ct

Objective: To investigate the role of whole-brain volume computed tomography (CT) perfusion in assessing early ischemic cerebrovascular diseases. Materials and Methods: Seventy-two patients with early ischemic cerebrovascular diseases who had undergone routine CT scan and 320-row volume CT whole-brain perfusion imaging within 8 h after admission were retrospectively enrolled in this one-center case-sectional study. The perfusion parameters of cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and dynamic CT angiogram (4D-CTA) were obtained and analyzed. Results: Among 72 patients, 29 cases with 37 cerebral ischemic lesions were found in plain CT scan, whereas 51 cases with 76 lesions were found in whole-brain CT perfusion, with 30.6% more patients being detected. The CBF value was significantly lower in the abnormal than normal corresponding perfusion area in the healthy hemisphere (P<0.05), while the MTT and TTP values were significantly higher in the abnormal than the normal corresponding area (P<0.05). 4D-CTA image suggested that 59 cases had different degrees of stenosis or occlusion, including 11 mild, 18 moderate, 21 severe, and 9 occlusive cases. Four-D-CTA imaging could detect significantly (P<0.05) more patients with abnormal perfusion in severe cerebral vascular stenosis or occlusion than those with no, mild or moderate stenosis (93.33% vs. 16.67%) (P<0.05). The stenosis of intracranial and carotid arteries was positively correlated with MTT and TTP values (P<0.05). Conclusion: Whole-brain volume CT angiography can comprehensively display early cerebral ischemic lesions, cerebral blood perfusion status, and cerebral vascular stenosis, providing valuable information for early detection of ischemic cerebral diseases and appropriate treatment planning.

Dominant role of aortic baroreceptors in the cardiac baroreflex of the rat in situ

2008 ◽  
Vol 142 (1-2) ◽  
pp. 32-39 ◽  
Author(s):  
Anthony E. Pickering ◽  
Annabel E. Simms ◽  
Julian F.R. Paton
Keyword(s):  
Dominant Role ◽  
Aortic Baroreceptors

Magnetic field assisted electrocatalytic oxygen evolution reaction of nickel-based materials

2022 ◽  
Author(s):  
Yuanyuan Zhang ◽  
Ping Guo ◽  
Siwei Li ◽  
Jianmin Sun ◽  
Wei Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Oxygen Evolution ◽  
Electron Scattering ◽  
Oxygen Evolution Reaction ◽  
Dominant Role ◽  
Testing System ◽  
Magnetoresistance Effect ◽  
Electrochemical Testing

The dominant role of the magnetoresistance effect caused by spin electron scattering in the oxygen evolution reaction is unveiled through an in situ tunable magnetic field-electrochemical testing system.

scholarly journals Dominant role of in situ native cartilage niche for determining the cartilage type regenerated by BMSCs

2021 ◽  
Author(s):  
Mengjie Hou ◽  
Baoxing Tian ◽  
Baoshuai Bai ◽  
Zheng Ci ◽  
Yu Liu ◽  
...  
Keyword(s):  
Dominant Role ◽  
Native Cartilage

ELECTRON SCATTERING IN BURIED InGaAs/HIGH-K MOS CHANNELS

2011 ◽  
Vol 20 (01) ◽  
pp. 95-103 ◽  
Author(s):  
S. OKTYABRSKY ◽  
P. NAGAIAH ◽  
V. TOKRANOV ◽  
M. YAKIMOV ◽  
R. KAMBHAMPATI ◽  
...  
Keyword(s):  
Dominant Role ◽  
Interface Layer ◽  
Barrier Thickness ◽  
Channel Mobility ◽  
High K ◽  
Amorphous Si ◽  
Inp Substrates ◽  
Low K

Hall electron mobility in buried QW InGaAs channels, grown on InP substrates with HfO 2 gate oxide, is analyzed experimentally and theoretically as a function of top barrier thickness and composition, carrier density, and temperature. Temperature slope α in μ ~Tα dependence is changing from α=-1.1 to +1 with the reduction of the top barrier thickness indicating the dominant role of remote Coulomb scattering (RCS) in interface-related contribution to mobility degradation. Insertion of low-k SiO x interface layer formed by oxidation of thin in-situ MBE grown amorphous Si passivation layer has been found to improve the channel mobility, but at the expense of increased EOT. This mobility improvement is also consistent with dominant role of RCS. We were able to a obtain a reasonable match between experiment and simple theory of the RCS assuming the density of charges at the high-k/barrier interface to be in the range of (2-4)×1013 cm-2.

Kinetically controlled superstructural phases at the Sb/Si (5 5 12) interface

2005 ◽  
Vol 891 ◽  
Author(s):  
Mahesh Kumar ◽  
Vinod Kumar Paliwal ◽  
Govind ◽  
A. G. Vedeshwar ◽  
S. M. Shivaprasad
Keyword(s):  
Surface Characterization ◽  
Room Temperature ◽  
Dominant Role ◽  
High Index ◽  
Adsorption And Desorption ◽  
Different Temperatures ◽  
Low Energy Electron ◽  
Electron Energy Loss

ABSTRACTThe adsorption of Sb on the high index Si (5 5 12) has been studied at higher substrate temperature (HT) (800°C), using in situ surface characterization techniques like Auger Electron Spectroscopy (AES), Low Energy Electron Diffraction (LEED), and Electron Energy Loss Spectroscopy (EELS). The surface morphology of this high index Si (5 5 12) surface has row like trenches along (110) direction. We have performed the study of Sb adsorption and desorption on the Si (5 5 12) substrate held at different temperatures. The different pathways adopted during adsorption and desorption have suggested the dominant role of kinetics I forming various surface phases on the Si (5 5 12) substrate. The adsorption at room temperature resulted in the formation of (225) surface phase, while the adsorption at 680°C resulted in the (337) phase. The sequential thermal desorption of the room temperature and high temperature adsorbed surface resulted in the formation of (337) phases at 800°C, with anisotropic growth along one direction. While the adsorption at 800°C resulted in the formation of anisotropic (337) like phases, the further increase in the coverage formed a 2x Si (225) phase. Annealing this 2x Si (225) phase again resulted in the formation of anisotropic (337) phase. Thus formation of interface by controlling the growth kinetics can result in the formation of various tailored structures with desired properties.

scholarly journals Global methane and nitrous oxide emissions from non-marine waters

2021 ◽  
Author(s):  
Yajing Zheng ◽  
Shuang Wu ◽  
Shuqi Xiao ◽  
Kai Yu ◽  
Xiantao Fang ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Dominant Role ◽  
Nitrous Oxide Emissions ◽  
Inland Waters ◽  
Natural Ecosystems ◽  
Marine Waters ◽  
Order Of Magnitude ◽  
Flux Component

Abstract Non-marine waters (i.e., rivers, reservoirs, lakes, ponds, streams and estuaries) are globally significant emitters of methane (CH4) and nitrous oxide (N2O) to the atmosphere, while global estimates of these emissions have been hampered due to the lack of a worldwide comprehensive database with the collection of complete CH4 and N2O flux components. Here we synthesize 2997 in-situ flux or concentration measurements of CH4 and N2O from 277 peer-reviewed publications to examine the role of non-marine waters in shaping climate change. Here we estimate that inland waters including rivers, reservoirs, lakes and streams together release 94.49 Tg CH4 yr− 1 (ebullition plus diffusion) and 1.52 Tg N2O yr− 1 (diffusion) to the atmosphere, yielding an overall CO2-equivalent emission total of 3.05 Pg CO2 yr− 1, representing roughly 59% of CO2 emissions (5.13 Pg CO2 yr− 1) from these four aquatic ecosystems, with lakes acting as the largest emitter for both trace gases. Ebullition is noticed as a dominant flux component, contributing up to 62–84% of total CH4 fluxes across all inland waters. Chamber-derived CH4 flux rates are significantly greater than those determined by diffusion model-based methods for commonly capturing of both diffusive and ebullitive fluxes. The synthesis of global N2O measurements projected that rivers exhibit the highest indirect N2O emission factor (EF5, 0.028%), while streams have the lowest EF5 value (0.015%). Our study reveals a major oversight in regional and global CH4 budgets from inland waters, caused by neglect of the dominant role of ebullition pathways in those emissions. The indirect EF5 values established in this study generally suggest an order of magnitude downward revision is required in current IPCC default EF5 values for inland waters and estuaries. Our findings further indicate that a comprehensive understanding of the magnitude and patterns of CH4 and N2O emissions from non-marine waters is essential in defining the way that these natural ecosystems shape our climate.

scholarly journals Role of microRNAs in Stroke and Poststroke Depression

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Han Yan ◽  
Min Fang ◽  
Xue-Yuan Liu
Keyword(s):  
Cerebral Ischemia ◽  
Noncoding Rnas ◽  
Cerebrovascular Diseases ◽  
Eukaryotic Cells ◽  
Poststroke Depression ◽  
Regulate Gene Expression ◽  
Diagnosis And Prognosis ◽  
Ischemic Cerebrovascular Diseases ◽  
Growth Development

microRNAs (miRNA), a sort of noncoding RNAs widely distributed in eukaryotic cells, could regulate gene expression by inhibiting transcription or translation. They were involved in important physiological and pathological processes including growth, development, and occurrence and progression of diseases. miRNAs are crucial for the development of the nervous system. Recent studies have demonstrated that some miRNAs play important roles in the occurrence and development of ischemic cerebrovascular diseases such as stroke and were also involved in the occurrence and development of poststroke depression (PSD). Herein, studies on the role of miRNAs in the cerebral ischemia and PSD were reviewed, and results may be helpful for the diagnosis and prognosis of cerebral ischemia and PSD with miRNAs in clinical practice.

Chronic Pain: Fundamental Scientific Considerations, Specifically for Legal Claims

2013 ◽  
Vol 18 (1) ◽  
pp. 1-18 ◽  
Author(s):  
Robert J. Barth
Keyword(s):  
Health Outcomes ◽  
Pain Perception ◽  
Driving Forces ◽  
Psychological Treatment ◽  
Dominant Role ◽  
Meta Analysis ◽  
General Medicine ◽  
Pain Syndrome ◽  
Problematic Relationship

Abstract Scientific findings have indicated that psychological and social factors are the driving forces behind most chronic benign pain presentations, especially in a claim context, and are relevant to at least three of the AMA Guides publications: AMA Guides to Evaluation of Disease and Injury Causation, AMA Guides to Work Ability and Return to Work, and AMA Guides to the Evaluation of Permanent Impairment. The author reviews and summarizes studies that have identified the dominant role of financial, psychological, and other non–general medicine factors in patients who report low back pain. For example, one meta-analysis found that compensation results in an increase in pain perception and a reduction in the ability to benefit from medical and psychological treatment. Other studies have found a correlation between the level of compensation and health outcomes (greater compensation is associated with worse outcomes), and legal systems that discourage compensation for pain produce better health outcomes. One study found that, among persons with carpal tunnel syndrome, claimants had worse outcomes than nonclaimants despite receiving more treatment; another examined the problematic relationship between complex regional pain syndrome (CRPS) and compensation and found that cases of CRPS are dominated by legal claims, a disparity that highlights the dominant role of compensation. Workers’ compensation claimants are almost never evaluated for personality disorders or mental illness. The article concludes with recommendations that evaluators can consider in individual cases.

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