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Distribution of trace metal concentrations in paired cancerous and non-cancerous human stomach tissues

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World Journal of Gastroenterology 2007年第4期13卷 612-618页

作者： Mehmet Yaman gokce kaya Hayrettin Yekeler Firat University Sciences and Arts Faculty Chemistry Department Elazig Turkey Chief of Staff in State Hospital Elazig Turkey

AIM: To assess whether trace metal concentrations (which influence metabolism as both essential and non-essential elements) are increased or decreased in cancerous tissues and to understand the precise role of these metals in carcinogenesis. METHODS: Concentrations of trace metals including Cd, Ni, Cu, Zn, Fe, Mg and Ca in both cancerous and non- cancerous stomach tissue samples were determined by atomic absorption spectrometry (AAS). Tissue samples were digested using microwave energy. Slotted tube atom trap was used to improve the sensitivity of copper and cadmium in flame AAS determinations. RESULTS: From the obtained data in this study, the concentrations of nickel, copper and iron in the cancerous human stomach were found to be significantly higher than those in the non-cancerous tissues, by using t-test for the paired samples. Furthermore, the average calcium concentrations in the cancerous stomach tissue samples were found to be significantly lower than those in the non-cancerous stomach tissue samples by using t-test. Exceedingly high Zn concentrations (207-826 mg/ kg) were found in two paired stomach tissue samples from both cancerous and non-cancerous parts. CONCLUSION: In contrast to the literature data for Cu and Fe, the concentrations of copper, iron and nickel in cancerous tissue samples are higher than those in the non-cancerous samples. Furthermore, the Ca levels are lower in cancerous tissue samples than in non-cancerous tissue samples.

关键词： Cancer Trace metals Human stomach Microwave energy Atomic absorption

Study on bi-directional pedestrian movement using ant algorithms

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Chinese Physics B 2016年第1期25卷 525-534页

作者： Sibel gokce Ozhan kayacan Department of Physics Faculty of Arts and Sciences Celal Bayar University

A cellular automata model is proposed to simulate bi-directional pedestrian flow. Pedestrian movement is investigated by using ant algorithms. Ants communicate with each other by dropping a chemical, called a pheromone, on the substrate while crawling forward. Similarly, it is considered that oppositely moving pedestrians drop ＇visual pheromones＇ on their way and the visual pheromones might cause attractive or repulsive interactions. This pheromenon is introduced into mod- elling the pedestrians＇ walking preference. In this way, the decision-making process of pedestrians will be based on ＇the instinct of following＇. At some densities, the relationships of velocity-density and flux-density are analyzed for different evaporation rates of visual pheromones. Lane formation and phase transition are observed for certain evaporation rates of visual pheromones.

关键词： cellular automata computer simulation bi-directional pedestrian flow phase transition

Surgical strategies for severely atherosclerotic(porcelain)aorta during coronary artery bypass grafting

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World Journal of Cardiology 2021年第8期13卷 309-324页

作者： gokce Sirin Department of Cardiovascular Surgery Biruni UniversityIstanbul 34010Turkey Department of Cardiovascular Surgery Camlica Medicana HospitalIstanbul 34692Turkey

Porcelain aorta(PA)is an asymptomatic atherosclerotic disease,characterized by circumferential calcification throughout the whole perimeter of the *** is seen in 2%to 9.3%of patients undergoing elective coronary artery bypass grafting(CABG)and makes manipulation of the ascending aorta *** has been clearly shown that most emboli seen and detected during the CABG procedure occur during aortic cross-clamping and aortic *** of porcelain or a severely atherosclerotic aorta increases the risk of perioperative *** incidence of stroke after CABG is between 0.48%and 2.9%,and the risk is correlated with the extent and severity of the atherosclerotic disease.A conventional CABG procedure involves successive steps that include cannulation of the ascending aorta,application of a cross-clamp to the aorta,and partial clamping of the aorta to create the proximal *** in procedures that involve cannulation,clamping,or proximal anastomosis,and where aortic manipulation is inevitable,preassessment of the atherosclerotic aortic plaques is *** many surgeons still rely on intraoperative manual aortic palpation,this approach has very low sensitivity and underestimates the severity of the atherosclerotic *** methods including preoperative computed tomography or intraoperative epiaortic ultrasonography enable modification of the surgical technique according to the severity of *** surgical techniques have been described to reduce the risk of atheroembolism that may lead to cerebrovascular events in patients with severely atherosclerotic ascending *** or“no-touch”techniques that do not utilize aortic manipulation may significantly decrease the development of neurological complications by avoiding aortic maneuvers known to cause *** cases where severe atherosclerotic disease or other factors preclude safe use of the ascending aorta,modifications in the surgical techniques

关键词： Coronary artery bypass grafting Cardiopulmonary bypass Severe atherosclerotic aorta Porcelain aorta Stroke Mortality

Cultural schema and design activity in an architectural design studio

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Frontiers of Architectural Research 2017年第2期6卷 183-203页

作者： gokce Ketizmen Onal Hulya Turgut Eskisehir Osmangazi University Department of Architecture Bademlik Campus Odunpazari-Eskisehir Turkey Ozyegin University Faculty of Architecture and Design Department of Architecture Nisantepe Mah. Orman Sok. Cekmekoy 34794 Istanbul Turkey

Research on the cognitive activities and on the structure and quality of knowledge flow involved in architectural design education is increasing. These studies generally focus on the interaction between student and instructor, including processes such as producing ideas, solving display problems, and integrating design strategies. These studies commonly include computational evaluations and confirmation of the coding of knowledge. They may also include the determination of designer＇s thoughts and cognitive actions of design process, as welt as the analysis and digitization of verbal protocols during the design process. In most of these studies, the designer＇s cultural and psychological components are not considered. Accordingly, research on the effects of designers＇ cultural schema on design activity in design studios is limited. This study aimed to solve this problem by analyzing the relationship between design activity and the designer＇s cultural schema in a design studio. We performed an experimental study based on a specific conceptual framework and a research model aimed at identifying the relationships among cultural schemas, the architectural design process, and design studios.

关键词： Cultural schema Architecturat designstudio Architectural designprocess Concurrent protocolanalysis method Cognitive-behavioral plan anatysis

Interaction between seed size and NaCl on germination and early seedling growth of some Turkish cultivars of chickpea(Cicer arietinum L.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第5期9卷 371-377页

作者： Muharrem kaya Gamze kaya Mehmet Demir kaya Mehmet ATAK Sevil SAGLAM Khalid Mahmood KHAWAR Cemalettin Yasar CIFTCI Department of Field Crops Faculty of AgricultureSuleyman Demirel University Central Research Institute for Field Crops Ministry of Agriculture and Rural Affairs Department of Field Crops Faculty of AgricultureMustafa Kemal University Department of Field Crops Faculty of AgricultureUniversity of Ankara

Chickpea is an important food legume crop of Turkey and is largely grown for human consumption on low moisture or salt-affected soils. The objective of the study was to find the effects of NaCl stress at electrical conductivities of 4.5, 8.6, 12.7 and 16.3 dS/m and seed sizes （7, 8 and 9 mm） on germination and early seedling growth of three popular chickpea cultivars （AKN-97, gokce and Uzunlu-99）. Mean frequency of germination, germination time, germination index, root length, shoot length and seedling fresh weight showed seed size-dependent responses ofcultivars to salt stress. In general, small seeds germinated and grew more rapidly compared to medium and large seeds of the same cultivars against all levels of salt stress, with the best results in cultivar Uzunlu-99. No effect of NaCl treatments was observed on frequency of germination; however, a drastic decrease in early seedling growth was recorded at increased NaC1 concentrations. Regression analysis results showed a significantly positive relationship （P〈0.01） between seed size and mean germination time, whereas a significantly negative relationship was recorded between seed size and germination index, root length, shoot length. Moreover, linear regression values apparently confirmed that increased seed size in each cultivar affected decreased germination index, root and shoot lengths with enhanced mean germination time. Thus, it was concluded that the use of small seeds could considerably reduce the production costs of chickpea in salt-affected soils.

关键词： Chickpea (Cicer arietinum L.) NaCl stress Cultivar Seed size Germination

Spring tube braces for seismic isolation of buildings

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 219-231页

作者： V.Karayel E.Yuksel T.gokce F.Sahin Institute of Science and Technology Istanbul Technical University lstanbul 34469 Turkey Faculty of Civil Engineering Istanbul Technical University Maslak Istanbu1 34465 Turkey

Abstract： A new low-cost seismic isolation system based on spring tube bracings has been proposed and studied at the Structural and Earthquake Engineering Laboratory of Istanbul Technical University. Multiple compression-type springs are positioned in a special cylindrical tube to obtain a symmetrical response in tension and compression-type axial loading. An isolation floor, which consists of pin-ended steel columns and spring tube bracings, is constructed at the foundation level or any intermediate level of the building. An experimental campaign with three stages was completed to evaluate the capability of the system. First, the behavior of the spring tubes subjected to axial displacement reversals with varying frequencies was determined. In the second phase, the isolation floor was assessed in the quasi-static tests. Finally, a scaled 3D steel frame was tested on the shake table using actual acceleration records. The transmitted acceleration to the floor levels is greatly diminished because of the isolation story, which effects longer period and higher damping. There are no stability and self- centering problems in the isolation floor.

关键词： seismic isolation spring tube base isolation low-cost isolation

Discussion on“Empirical methods for determining shaft bearing capacity of semi-deep foundations socketed in rocks”[J Rock Mech Geotech Eng 6(2017)1140-151]

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第3期10卷 603-606页

作者： Ergin Arioglu Pinar Toru Seker Hasan Burak gokce Yapi Merkezi Construction and Industry Inc. IstanbulTurkey

A new comprehensive set of data（n = 178） is compiled by adding a data set（n = 72） collected by Arioglu et al.（2007） to the data set（n = 106） presented in Rezazadeh and Eslami（2017）. Then, the compiled data set is evaluated regardless of the variation in lithology/strength. The proposed empirical equation in this study comprises a wider range of uniaxial compressive strength（UCS）（0.15 MPa 〈 σ_（rc）〈156 MPa） and various rock types. Rock mass cuttability index（RMCI） is correlated with shaft resistance（r_s） to predict the shaft resistance of rock-socketed piles. The prediction capacity of the RMCI versus r_s equation is also found to be in a fair good agreement with the presented data in Rezazadeh and Eslami（2017）. Since the RMCI is a promising parameter in the prediction of shaft resistance, the researchers in the rock-socketed pile design area should consider this parameter in the further investigations.

关键词： Uniaxial compressive strength (UCS) Rock mass cuttability index (RMCI) Shaft resistance Rock socketed piles Database

Differences in physiological and biochemical responses to summer drought of Pinus nigra *** and Pinus brutia in a natural mixed stand

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Journal of Forestry Research 2020年第5期31卷 1479-1487页

作者： Ayse Deligoz Fatma gokce Cankara Faculty of Forestry Isparta University of Applied Sciences32260 IspartaTurkey

Understanding how tree species respond to drought in their natural environment is needed to predict forest adaptation and management practices under global environmental *** study was carried out to determine and compare physiological and biochemical responses to variations in environmental conditions during summer drought of mixed natural stands of Pinus nigra ***(Lamb.)Holmboe and Pinus brutia *** xylem water potential(ψmd),water relations,photosynthetic pigments,total soluble sugar and proline contents were investigated during the growing season.ψmd followed a similar seasonal trend in both species but *** *** had higher ψmd than *** ψmd gradually decreased from June,reached its lowest value in August,and then increased *** decreases in the osmotic potential at turgor loss point(ψnTLP)were observed during the ***,ψnTLP was lower in *** soluble sugars decreased from April to June for ***,then increased and stayed relatively constant August to *** changes were found at lower values in *** *** accumulation and photosynthetic pigments were higher in *** results indicate that physiological and biochemical responses of both species against changing environmental conditions were in different degrees but followed similar *** *** is more sensitive to summer drought than *** in their natural environment.

关键词： Pinus nigra subsp.pallasiana Pinus brutia Osmotic potential Photosynthetic pigments Soluble sugars Proline Summer drought

Evaluation of ischemic lesions after carotid artery stenting with diffusion-weighted imaging

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World Journal of Clinical Cases 2020年第10期8卷 1859-1870页

作者： Murat Beyhan Berat Acu Erkan gokce Mehmet Murat Firat Department of Radiology Tokat Gaziosmanpasa University Faculty of MedicineTokat 60100Turkey Department of Radiology Eskisehir Osmangazi University Faculty of MedicineEskisehir 26480Turkey Department of Radiology Guven HospitalAnkara 06540Turkey

BACKGROUND Almost 90%of cerebral thromboembolism cases are caused by *** atherosclerosis is often observed at the carotid bifurcation and is responsible for 20%-30%of all stroke *** course of atherosclerotic carotid artery stenosis varies depending on the grade of stenosis and characteristics of the *** artery stenting(CAS)can be used as a less invasive method in patients with symptomatic and asymptomatic high-grade carotid artery ***-weighted imaging(DWI)is an effective method for detection of silent or symptomatic acute ischemic lesions that may arise due to CAS or carotid *** number and volume of new ischemic lesions are determined using *** To evaluate the number and volume of ischemic lesions and their cerebral parenchymal and vascular distribution after CAS using *** Forty-seven male(73.4%)and seventeen female(26.6%)patients(total,n=64)aged 42-84 years(mean 67.96±8.03 years)diagnosed with carotid stenosis between October 2006 and July 2012 were included in this retrospective *** of the cases(18.8%)were asymptomatic,while fifty-two(81.2%)were *** area where the stenosis was highest was measured,and the stenosis rate was determined using the North American Symptomatic Carotid Endarterectomy Trial *** of the cases was evaluated by two radiologists experienced in neuroradiology(*** more than 15 years of experience,*** more than 10 years of experience).Routine DWI examinations were carried out by a 1.5 T MR device 1 h before and after the *** the ischemic lesions that developed in the first hour and in the follow-up period of 5-24 h were assumed to be due to CAS,all lesions within the first 24 h were considered as new *** In the present study,39 new ischemic lesions were detected in 20 *** average number of new lesions after all CAS operations was *** were mostly located in the occipital lobes,followed by

关键词： Carotid artery stenosis Carotid artery stenting Diffusion-weighted imaging Ischemia Stroke