检索结果-南通市图书馆

Kd-tree and quad-tree decompositions for declustering of 2D range queries over uncertain space

在线全文

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2015年第2期16卷 98-108页

作者： ahmet sayar Suleyman EKEN Okan OZTURK Department of Computer Engineering Kocaeli University Kocaeli 41380 Turkey

We present a study to show the possibility of using two well-known space partitioning and indexing techniques, kd trees and quad trees, in declustering applications to increase input/output （I/O） paraUelization and reduce spatial data processing times. This parallelization enables time-consuming computational geometry algorithms to be applied efficiently to big spatial data rendering and querying. The key challenge is how to balance the spatial processing load across a large number of worker nodes, given significant performance heterogeneity in nodes and processing skews in the workload.

关键词： Kd tree Quad tree Space partitioning Spatial indexing Range queries Query optimization

A model‑free approach to do long‑term volatility forecasting and its variants

在线全文

学校读者我要写书评

暂无评论

Financial Innovation 2023年第1期9卷 1595-1632页

作者： Kejin Wu sayar Karmakar Department of Mathematics University of California San DiegoLa JollaUSA Department of Statistics University of FloridaGainesvilleUSA

Volatility forecasting is important in financial econometrics and is mainly based on the application of various GARCH-type ***,it is difficult to choose a specific GARCH model that works uniformly well across datasets,and the traditional methods are unstable when dealing with highly volatile or short-sized *** newly pro-posed normalizing and variance stabilizing(NoVaS)method is a more robust and accu-rate prediction technique that can help with such *** model-free method was originally developed by taking advantage of an inverse transformation based on the frame of the ARCH *** this study,we conduct extensive empirical and simu-lation analyses to investigate whether it provides higher-quality long-term volatility forecasting than standard GARCH ***,we found this advantage to be more prominent with short and volatile ***,we propose a variant of the NoVaS method that possesses a more complete form and generally outperforms the current state-of-the-art NoVaS *** uniformly superior performance of NoVaS-type methods encourages their wide application in volatility *** analyses also highlight the flexibility of the NoVaS idea that allows the exploration of other model structures to improve existing models or solve specific prediction problems.

关键词： ARCH-GARCH Model free Aggregated forecasting

The Relationship Between Integrated Reporting and Financial Reporting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Management Studies 2014年第7期2卷 465-478页

作者： Ipek Turker A.R Zafer sayar Istanbul University Istanbul Turkey TOBB Economy and Technology University Ankara Turkey

With globalized world, expectations about business＇ role in the society and the world have increased; rather than just calculating profit and recording it, business has taken a step further. Accordingly, the social responsibility reporting, sustainability reporting, and environmental reporting concepts have emerged. Financial reporting just focuses on a portion of the company＇s status and is unable to show the effects of environmental factors, climate changes on the companies. In addition, sustainability reporting was unable to show financial data which aims to see the risks and opportunities better, improves corporate reputation, and evaluates the performance of the company in accordance with the laws and norms. Investors need to establish a relationship between the financial and non-financial information in order to carry out risk analysis, as a result, the idea of integrated reporting has arised. Many companies have willingly started to prepare integrated reports in various formats and every report has been formed in accordance with the needs of readers and business properties. In addition, integrated reporting principles and guidelines have been published by the International Integrated Reporting Council, in order to provide guidance to report preparers. With the increasing importance and spread of integrated reporting, debates about the benefits and problems encountered in the preparation increased. In this study, the followings are explained： the terms of financial reporting, sustainability reporting, and financial reporting; emergence of these terms; benefits of integrated reporting and problems that may be encountered while preparation; and the relationship between financial reporting and integrated reporting.

关键词： integrated reporting financial reporting sustainability reporting social responsibility reporting environmental reporting

Level of Cardiac Biomarkers in Immediate Post-Operative Period after Off-Pump CABG and Its Comparison with On-Pump CABG: A Prospective Analytical Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Cardiovascular Surgery 2020年第10期10卷 200-211页

作者： sayar Kumar Munshi Ashis Halder Pares Bandyopadhyay Congenital Cardiac Surgery Fortis Escorts Heart Institute New Delhi India Cardiothoracic & Vascular Surgery Nilratan Sircar Medical College & Hospital Kolkata India

Background: Coronary artery bypass grafting (CABG) is an important modality of treatment for ischemic heart disease. Both off-pump and on-pump CABG have direct effect on the level cardiac biomarkers in the perioperative period. The use of cardiopulmonary bypass (CPB) and aortic cross-clamping may cause additive myocardial damage leading to further elevation of blood markers. The present study is aimed at measuring and comparing the cardiac biomarker levels in immediate post-operative period after on-pump CABG (ONCAB) and off-pump CABG (OPCAB). Methods: All the patients who underwent CABG from January 2015 to June 2016 on elective or emergency basis at Nilratan Sircar Medical College & Hospital have been included in the study. Total 106 patients were operated for CABG of which 75 patients were operated for OPCAB and 31 patients were operated for ONCAB. For the comparison of data the blood markers Troponin-T (Trop-T) and Creatine Kinase-MB (CK-MB) are measured during anesthesia before surgery, post-operatively after 1 hour, post-operatively after 4 hours and post-operatively after 20

关键词： Coronary Artery Bypass Grafting (CABG) Perioperative Period Myocardial Damage Cardiopulmonary Bypass Cardiac Biomarkers

Cardiovascular Function during First 24 Hours after Off-Pump and On-Pump CABG—A Prospective Observational Comparative Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Cardiovascular Surgery 2023年第4期13卷 71-83页

作者： sayar Kumar Munshi Ashis Halder Pares Bandyopadhyay Cardiothoracic & Vascular Surgery Nilratan Sircar Medical College & Hospital Kolkata India

Purpose: Myocardial revascularization by coronary artery bypass grafting (CABG) in ischemic heart disease patients has direct impact on hemodynamic parameters in the immediate post-operative period. The peri-operative cardiovascular functioning is an important determinant for outcome of surgery. In On-Pump CABG (ONCAB), the cardiopulmonary bypass has a negative effect on myocardium. Off-Pump CABG (OPCAB) avoids the effect of CPB but complete revascularization with difficult positioning of heart is technically demanding. This study is aimed to compare the cardiovascular functioning in the immediate post-operative period after OPCAB and ONCAB. Methods: Total 106 patients were operated for CABG from January 2015 to June 2016, of which 75 patients were operated for OPCAB and 31 patients were operated for ONCAB. For the comparison, hemodynamic parameters were measured during anesthesia before surgery, postoperatively after 1 and 4 hours (h) in the ICU, and in the morning after surgery, approximately after 20 h. Results: The time-dependent rise of hemodynamic parameters like Cardiac Output (CO), Cardiac Index (CI), Stroke volume (SV) and Left Ventricular Stroke Work Index (LVSWI) in the immediate post-operative hours (1 h and 4 h) are more predominant in OPCAB group than ONCAB group although the difference is eliminated mostly at 20 h. The better peripheral vasodilation after OPCAB causes immediate fall of Systemic Vascular Resistance Index (SVRI) after OPCAB. Conclusion: Better cardiovascular functioning immediately after OPCAB than ONCAB may be important for better hemodynamic stability. The difference is however eliminated after 24 hours indicating little significance in long term outcome.

关键词： Off-Pump CABG On-Pump CABG Cardiac Index Stroke Volume Left Ventricular Stroke Work Index Systemic Vascular Resistance Index

Does the intrathecal propofol have a neuroprotective effect on spinal cord ischemia?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2015年第11期10卷 1825-1829页

作者： Murat Sahin Huriye Gullu Kemal Peker Ilyas sayar Orhan Binici Huseyin Yildiz Department of Anesthesiology and Reanimation Faculty of Medicine University of Amasya Department of Anesthesiology and Reanimation Mengucek Gazi Research and Training Hospital Department of General Surgery Faculty of Medicine University of Erzincan Department of Pathology Faculty of Medicine University of Erzincan Department of Anesthesiology and Reanimation Faculty of Medicine University of Sutcu Imam

The neuroprotective effects of propofol have been confirmed. However, it remains unclear whether intrathecal administration of propofol exhibits neuroprotective effects on spinal cord ischemia. At 1 hour prior to spinal cord ischemia, propofol（100 and 300 μg） was intrathecally administered in rats with spinal cord ischemia. Propofol pre-treatment greatly improved rat pathological changes and neurological function deficits at 24 hours after spinal cord ischemia. These results suggest that intrathecal administration of propofol exhibits neuroprotective effects on spinal cord structural and functional damage caused by ischemia.

关键词： nerve regeneration propofol pre-treatment spinal cord ischemia neuroprotection paraplegia neural regeneration

P2X7 Receptors Utilize Different Pathways for Fluorescent Dye Uptake in Different Cell Types

在线全文

学校读者我要写书评

暂无评论

P2X7 Receptors Utilize Different Pathways for Fluorescent Dy...

Warm tachyon inflation and swampland criteria

第十五届国际药理学大会

作者： Ugur Mehmet Cankurtaran Serife sayar Kemal Ankara Univ. Fac.Medicine. Dent. Biophysics Ankara TURKEY. Ankara Univ. Fac.Medicine. Dent. Biophysics Ankara TURKEY. Ankara Univ. Fac.Medicine. Dept. Pharmacology Ankara TURKEY.

＜正＞ We investigated the P2X7 receptor mediated uptake of three different dyes （Lucifer yellow, ethidium bromide and YO - PRO1） in both RAW and rP2X7 expressing HEK - 293 cells （HEK - K4） using single cell imaging, PMT measurements and fluorescent microscopy techniques. Both RAW and HEK - K4 cells showed clear YO - PRO and ethidium bromide uptake upon ATP （1 mM） application. On the other hand while P2X7 stimulation induced an apparent lucifer yellow uptake in RAW cells, it did not stimulate any uptake in HEK - K4 cells. This clear lack of lucifer yellow uptake in HEK - K4 cells is not due to extensive disruption of the cell membrane by P2X7 receptor stimulation, rendering it incapable of holding the soluble dye in its cytoplasm, as these cells did not show any leakage of FURA2 during this stimulation period. Our results suggest that the pathway which is responsible for the fluorescent dye uptake in HEK cells is different than the one in RAW cells.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Chinese Physics C 2020年第9期44卷 162-174页

作者： Abolhassan Mohammadi Tayeb Golanbari Haidar Sheikhahmadi Kosar sayar Lila Akhtari M.A.Rasheed Khaled Saaidi Department of Physics Faculty of ScienceUniversity of KurdistanPasdaran St.P.O.Box 66177-15175SanandajIran Development Center for Research and Training(DCRT) University of Human DevelopmentSulaimaniKurdistan RegionIraq Center for Space Research North-West UniversityMafikengSouth Africa School of Astronomy Institute for Research in Fundamental Sciences(IPM)P.O.Box 19395-5531TehranIran Department of Physics College of ScienceUniversity of SulaimaniSulaimaniKurdistan RegionIraq

In this study,the scenario of a two-component warm tachyon inflation is considered,where the tachyon field plays the role of the inflaton by driving the *** inflation,the tachyon scalar field interacts with the other component of the Universe,which is assumed to be photon gas,i.e.,*** interacting term contains a dissipation coefficient,and the study is modeled based on two different and familiar choices of the coefficient that were studied in the *** employing the latest observational data,the acceptable ranges for the free parameters of the model are *** any choice within the estimated ranges,there is an acceptable concordance between the theoretical predictions and *** the model is established based on several assumptions,it is crucial to verify their validity for the obtained values of the free parameters of the *** is found that the model is not self-consistent for all values of the ranges,and for some cases,the assumptions are ***,to achieve both self-consistency and agreement with the data,the parameters of the model must be ***,we consider the recently proposed swampland conjecture,which imposes two conditions on the inflationary *** criteria rule out some inflationary models;however,warm inflation is among those that successfully satisfy the swampland *** conduct a precise investigation,which indicates that the proposed warm tachyon inflation cannot satisfy the swampland criteria for some *** fact,for the first case of the dissipation coefficient,in which,there is dependency only on the scalar field,the model agrees with observational ***,it is in direct tension with the swampland ***,for the second case,wherein the dissipation coefficient has a dependency on both the scalar field and temperature,the model exhibits acceptable agreement with observational data,and suitably satisfies the swampland criteria.

关键词： warm inflation tachyon scalar field slow-roll approximation swampland criterion

Effect of body mass index on functional outcomes following arthroplasty procedures

在线全文

学校读者我要写书评

暂无评论

World Journal of Orthopedics 2015年第11期6卷 991-995页

作者： Gokhan Polat Hasan Huseyin Ceylan Safak sayar Fatih Kucukdurmaz Mehmet Erdil Ibrahim Tuncay Department of Orthopaedics and Traumatology Istanbul University Istanbul Medical Faculty Department of Orthopedics and Traumatology Sultanciftligi LNB State Hospital Department of Orthopaedics and Traumatology Bezmialem Vakif University Department of Orthopaedics and Traumatology Istanbul Medipol University

AIM: To evaluate the body mass index(BMI) change in arthroplasty patients and its impact on the patients' functional results. METHODS: Between October 2010 and May 2013, 606 patients who were operated due to gonarthrosis, coxarthrosis, aseptic loosening of the total knee and hip prosthesis were evaluated prospectively. Patients were operated by three surgeons in three medical centers. Patients who were between 30-90 years of age and who were underwent total knee arthroplasty, total hip arthroplasty, revision knee arthroplasty, or revision hip arthroplasty were included in the study. We excluded the patients who cannot tolerate our standard postoperative rehabilitation program. Additionally, patients who had systemic inflammatory diseases, diabetes mellitus, or endochrinopathies were excluded from the study. The remaining 513 patients comprised our study group. Preoperative functional joint scores, height, weightand BMI of all patients were recorded. We used the Knee Society Score(KSS) for knee and Harris Hip Score(HHS) for hip patients. Postoperative functional scores were measured at 1^(st), 6^(th) and 12^(th) months and recorded separately at outpatient visits. RESULTS: The mean age of the patients was 64.7(range: 30-90) years(207 males/306 females) and the mean follow-up duration was 14.3(range: 12-26) mo. We found that arthroplasty patients had weight gain and had an increase in BMI at the postoperative 1^(st), 6^(th) and 12^(th) months. The mean BMI of the patients was 27.7 preoperatively, 27.8 at the postoperative 1^(st) month, 28.1 at the 6^(th) month and 28.6 at the 12^(th) month(P < 0.01). At the last visit, the mean postoperative HHS of the hip arthroplasty patients was 82.2 ± 7.12(preoperatively, 52.3; 1st month, 78.2; 6^(th) month, 81.1; 12^(th) month, 82.2), and the mean KSS of the knee arthroplasty patients was 79.3 ± 4.31(preoperatively, 35.8; 1^(st) month, 75.2; 6^(th) month, 79.1; 12^(th) month, 79.3). Worse functional results were noted in the pati

关键词： Body mass index Arthroplasty Obesity Functional outcomes Weight gain