Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 3 )

2018 ( 5 )

2017 ( 2 )

2016 ( 12 )

Custom range...

Search Results: 1 - 10 of 1840 matches for " Murat;Bugan "
All listed articles are free for downloading (OA Articles)
Page 1 /1840
Display every page Item
High admission levels of γ-glutamyltransferase predict poor myocardial perfusion after primary percutaneous intervention
Yuksel, Uygar Cagdas;Celik, Turgay;Celik, Murat;Bugan, Baris;Iyisoy, Atila;Yaman, Halil;
Clinics , 2011, DOI: 10.1590/S1807-59322011001000010
Abstract: objective: this retrospective study aimed to investigate the relationship between admission levels of serum y-glutamyltransferase and poor myocardial perfusion after primary percutaneous coronary intervention in patients with acute myocardial infarction. introduction: reperfusion injury caused by free radical release and increased oxidative stress is responsible for the pathophysiology of the no-reflow phenomenon in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention. serum ?-glutamyltransferase is an established marker of increased oxidative stress. methods: the study population consisted of 80 patients (64 men and 16 women, mean age = 67.5 + 6.6 years) with thrombolysis in myocardial infarction 0/1 flow pre-procedurally. the patients were divided into two groups according to thrombolysis in myocardial perfusion grades that were assessed immediately following primary percutaneous coronary intervention. the two groups (group 1 and group 2) each consisted of 40 patients with thrombolysis in myocardial perfusion grades 0-1 and thrombolysis in myocardial perfusion grades 2-3, respectively. results: admission pain to balloon time, ?-glutamyltransferase and creatine kinase-mb isoenzyme levels of group 1 patients were significantly higher than those of group 2 patients. pain to balloon time, ?-glutamyltransferase, peak creatine kinase-mb isoenzyme, low left ventricular ejection fraction and poor pre-procedural thrombolysis in myocardial infarction grade were significantly associated with poor myocardial perfusion by univariate analysis. however, only pain to balloon time and ?-glutamyltransferase levels showed a significant independent association with poor myocardial perfusion by backward logistic regression analysis. adjusted odds ratios were calculated as 4.92 for pain to balloon time and 1.13 for ?-glutamyltransferase. conclusion: high admission ?-glutamyltransferase levels are associated with poor myocardial perfusion in pa
The water balance of a seasonal stream in the semi-arid Western Cape (South Africa)
RDH Bugan, NZ Jovanovic, WP De Clercq
Water SA , 2012,
Abstract: A detailed water balance and conceptual flow model was calculated and developed for the Sandspruit catchment for the period 1990 to 2010 on a winter rainfall water-year (1 April - 31 March) basis. The Sandspruit catchment (quaternary catchment G10J) is located in the Western Cape Province of South Africa and is a tributary of the Berg River. It contributes significantly to the salinisation of the mid- to lower-reaches of the Berg River and thus the hydrological drivers need to be quantified and conceptualised in order to develop salinity management strategies. Various components of the water balance, i.e. precipitation, evaporation, streamflow, recharge, etc., were monitored and quantified. In addition, stable environmental isotopes and water balance modelling were used to perform hydrograph separation as well as to quantify components of the water balance. Annual streamflow in the catchment during the period of observation was variable, ranging between 0.026 mm·a-1 and 75.401 mm·a-1. Streamflow volumes also exhibit high variability between water years. Catchment annual rainfall varied between 351 and 655 mm·a-1, averaging at 473 mm·a-1. On average, 6.5% of rainfall was converted to streamflow during the period of observation. Evapotranspiration was found to be the dominant component of the water balance, as it comprises, on average, 94% of precipitation in the catchment. Groundwater recharge was calculated to average at 29 mm·a-1. The water balance model (J2000) performed well during the simulation period with all measures of performance exhibiting acceptable values. Simulation results indicate that streamflow is driven by interflow from the soil horizon (94.68% of streamflow), followed by overland flow (4.92% of streamflow). These results, together with the physiographic conditions evident in the catchment, were used to develop a conceptual flow model. Streamflow is interpreted to be driven by quickflow, i.e. overland flow and interflow, with minimal contribution from groundwater, and is also more dependent on the rainfall distribution in time rather than on the annual volume. The correlation between average annual streamflow and average rainfall was observed to be poor, suggesting that alternative factors, e.g. the spatial distribution of winter wheat, the temporal distribution of rainfall, climatic variables (temperature), etc., exert a greater influence on streamflow. The water balance and conceptual flow model will form the basis for the application of distributed hydrological modelling in the Sandspruit catchment and the development of salinity management strategies. Results from this investigation, e.g. ET estimates, methods to quantify groundwater recharge, hydrograph separation, etc., could potentially be extrapolated to other semi-arid areas.
The Effect of Students’ Learning Styles to Their Academic Success  [PDF]
Murat Gokalp
Creative Education (CE) , 2013, DOI: 10.4236/ce.2013.410090
Abstract: This study was aimed to evaluate the learning styles of education faculty students and to determine the effect of their success and relationship between their learning styles and academic success. The popula- tion of this study is comprised of the students of Education Faculty in 19 May University and the sample includes 140: 68 art, 72 pre-school teacher department students. Depending on the results obtained from pre-test, it was aimed to improve students’ knowledge and skills in studying. There was a significant dif- ference between the scores of pre- and post-tests. The significant relationship between the scores of post-test and the student success revealed that they learned how to study effectively. The validity and re- liability of the test were determined by considering the Cronbach alpha coefficients for each and all of the items. The study has found statistically significant differences between the results of the first and final applications of the subtests on learning styles and academic success; those subtests covered the items as learning, planned study, effective reading, listening, writing, note taking, using the library, getting pre- pared for and taking exams, class participation and motivation.
Extension of Kerberos with X.509 and Integration of Elliptic Curve Cryptography in Authentication  [PDF]
Murat Akkaya
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2016, DOI: 10.4236/ijcns.2016.912046
Abstract: Kerberos is one of the solutions for network security problems since it provides strong secret key cryptography over the insecure networks. Through the Kerberos authentication protocol, a client can prove its identity to a server (and vice versa) across an insecure network connection such as on Internet. In this comparative research paper, the Kerberos authentication protocol is extended and strengthened using x.509 with the integration of newer authentication system which is compared with previous authentication systems. In addition to this, RSA encryption mechanism used to provide authentication and security for the most communication systems replaced with Elliptic Curve Cryptography (ECC) encryption in Kerberos during authentication progress through simulation to expose possible efficient alternatives for key generation and to enhance security.
Wellens' syndrome with segmental wall-motion abnormalities
Turgay Celik, Baris Bugan, Serdar Firtina, et al
Open Access Emergency Medicine , 2010, DOI: http://dx.doi.org/10.2147/OAEM.S14484
Abstract: s' syndrome with segmental wall-motion abnormalities Case report (2840) Total Article Views Authors: Turgay Celik, Baris Bugan, Serdar Firtina, et al Published Date December 2010 Volume 2010:2 Pages 87 - 89 DOI: http://dx.doi.org/10.2147/OAEM.S14484 Turgay Celik1, Baris Bugan1, Serdar Firtina1, Murat Celik2, Sait Demirkol1, Atila Iyisoy1 1Gulhane Military Medical Academy, Department of Cardiology, Ankara, Turkey; 2Van Army District Hospital, Department of Cardiology, Van, Turkey Abstract: Wellens' syndrome is a pattern of electrocardiographic T-wave changes associated with critical, proximal left anterior descending (LAD) artery stenosis. We herein report 2 cases of Wellens' syndrome with segmental wall-motion abnormalities The first case is a 50-year-old man admitted to the emergency department with typical chest pain. Admission ECG showed biphasic T waves in leads V1–V3 with inverted T waves in leads V4–V6, and cardiac enzymes were in normal limits. The second case is a 62-year-old woman admitted to the emergency department with chest pain on rest. Admission ECG showed deeply inverted T waves in leads V1–V4, and troponin T was minimally elevated. The critical lesions in the proximal segment LAD were successfully opened with stent deployments. Wall-motion abnormalities returned to normal after intervention.
Speckle tracking based myocardial velocities: our experience with novel software
Oben Baysan,Mesut Akyol,Bar?? Bugan,Mehmet Yoku?o?lu
Anadolu Kardiyoloji Dergisi , 2010,
Abstract: Objective: Speckle tracking is a new imaging modality capable of providing information about myocardial motion in all three directions: longitudinal, circumferential and radial. There are many software packages with their unique tracking algorithms and user interfaces in the market. We aimed to evaluate the feasibility of QLAB software in clinical practice and speckle based myocardial velocities in healthy subjects. Methods: Thirty-two subjects were enrolled in the study. Images from apical four-chamber, apical two-chamber, parasternal short-axis (mitral valve-apical levels) views were acquired and analyzed offline with QLAB. We measured speed and velocity data in longitudinal, circumferential and radial directions. Time percent of these events were also calculated. In the final data analysis 825 of 832 segments (99.2%) were included. Mann Whitney U, Student’s t and Kendall’s tau-b coefficient tests were used for statistical analysis.Results: We determined that circumferential speed was significantly higher (p<0.001) than radial velocity in both parasternal short-axis views. Likewise, longitudinal speed was higher (p<0.001) than radial velocity in apical views. Notwithstanding the speed and velocity data, time percent of radial velocity were significantly lower (p<0.001 for all) than their longitudinal or circumferential counterparts. We also notified that apex was the segment reaching its maximum speed at earliest time. QLAB measurement time was relatively long (8.1±1.7 min) and intraobserver agreement was lost in 3% of the segments. Conclusion: In addition to these findings, we consider QLAB software package for speckle tracking needs some improvements to shorten measurement time and decrease user intervention.
A case of Ebstein anomaly and biventricular noncompaction
Oben Baysan,Mehmet Yoku?o?lu,Bar?? Bugan,Sait Demirkol
Anadolu Kardiyoloji Dergisi , 2010,
Rainfall, Soil Water Content, and Groundwater Levels at the Riverlands Nature Reserve (South Africa)
Nebo Jovanovic,Richard D. H. Bugan,Sumaya Israel
Dataset Papers in Science , 2013, DOI: 10.7167/2013/724819
Abstract: Quantified medium- and long-term hydrological datasets are scarce in South Africa, yet they are essential to gain understanding of natural systems, contribute to ecosystem conservation, and ultimately quantify water balance processes accurately. A hydrological experiment was carried out at Riverlands Nature Reserve (Western Cape, South Africa) in order to quantify the components of the soil water balance at experimental sites occupied by endemic and invasive vegetation. In two separate follow-up projects, five-year time series were collected in three treatments, namely, endemic fynbos vegetation, bare soil, and land invaded by Acacia saligna. Rainfall was recorded daily with a manual rain gauge. Groundwater levels were logged hourly at 14 boreholes. Volumetric soil water contents and soil temperatures were logged hourly at different depths in the soil profile. Groundwater levels and soil water contents responded to rainfall with very clear seasonal trends. The data can be applied in water balance and evapotranspiration studies, unsaturated flux studies, soil temperature profile studies, and rainfall-groundwater level response analysis and for calibrating and validating a wide range of hydrological models. 1. Introduction The quantification of water resources and the water cycle are of utmost importance in water resources planning and management. Previous studies have indicated that water resources use and availability are dynamic depending on climate, population, land use, economic growth, technological change, and other socioeconomic factors [1]. It is therefore essential to monitor the components of the water balance in order to describe these dynamic trends. The importance of long-term monitoring in natural sciences is also acknowledged as this helps in understanding complex ecological systems and evaluating disturbances due to changes in land use, management, and climate [2]. Long-term monitoring also contributes to national and international networks for the large-scale assessment of water resources [3]. This is particularly important when historic data are scarce, especially in arid regions that experience water stress, where knowledge of the water use of vegetation could have enormous implications to water resources management. Ultimately, monitored data are used in a variety of methods and models for water resources assessment, planning, and management interventions [4]. Alien invasive plants are species introduced in an area due to intentional or accidental human activity and have the potential to spread over a considerable area [5]. In recent
The Effects of Objects-First and Objects-Late Methods on Achievements of OOP Learners  [PDF]
Murat Pasa Uysal
Journal of Software Engineering and Applications (JSEA) , 2012, DOI: 10.4236/jsea.2012.510094
Abstract: Our research explored the effects of objects-first and objects-late methods on achievements of object-oriented pro-gramming (OOP) learners during a graduate course. The course’s scope was virtually identical for two groups, but the structure of the contents differed in sequence. The objects-first method emphasized the design and discussion of the object-oriented concepts from the very beginning while the objects-late deferred these concepts to the late lectures. The objects-first learners used all visual functionalities of BlueJ IDE. However, the objects-late learners started with only the text-based interfaces of BlueJ and they benefited its visual support in the last lectures. At the end of the study, we found that there was a statistically significant difference between OOP learner groups.
Fault Tolerance Mechanisms in Distributed Systems  [PDF]
Arif Sari, Murat Akkaya
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2015, DOI: 10.4236/ijcns.2015.812042
Abstract: The use of technology has increased vastly and today computer systems are interconnected via different communication medium. The use of distributed systems in our day to day activities has solely improved with data distributions. This is because distributed systems enable nodes to organise and allow their resources to be used among the connected systems or devices that make people to be integrated with geographically distributed computing facilities. The distributed systems may lead to lack of service availability due to multiple system failures on multiple failure points. This article highlights the different fault tolerance mechanism in distributed systems used to prevent multiple system failures on multiple failure points by considering replication, high redundancy and high availability of the distributed services.
Page 1 /1840
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.