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Modeling of dynamic response of poroelastic soil layers under wave loading

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Frontiers of Structural and civil Engineering 2014年第1期8卷 1-18页

作者： Mehmet baris can ULKER Earthquake Engineering and Disaster Management Institute Istanbul Technical University Istanbul 34469 Turkey

In this paper, the dynamic response of saturated and layered soils under harmonic waves is modeled using the finite element method. The numerical results are then verified by corresponding analytical solutions which are also developed by the author. The equations governing the dynamics of porous media are written in their fully dynamic form and possible simplifications are introduced based on the presence of inertial terms associated with solid and fluid phases. The response variations are presented in terms of pore water pressure and shear stress distributions within the layers. It is determined that a set of non-dimensional parameters and their respective ratios as a result of layering play a major role in the dynamic response.

关键词： dynamic response of soils coupled flow-deformation finite elements analytical solution harmonic waves

clinical and hemodynamic profiles of elderly patients with pulmonary arterial hypertension： a single center, prospective study

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Journal of Geriatric cardiology 2017年第1期14卷 20-27页

作者： Ebru Ozpelit Bahri Akdeniz Dilek Sezgin can Sevinc Kemal can Tertemiz Mehmet Emre Ozpelit Mustafa baris Nezihi baris Department of cardiology School of Medicine Dokuz Eylul University Izmir Turkey Department of lnternal Medicine Faculty of Nursing Dokuz Eylul University Izmir Turkey Department of chest Disease School of Medicine Dokuz Eylul University Izmir Turkey Department of cardiology Medicalpark Hospital Izmir Turkey Department of Radiology School of Medicine Dokuz Eylul University Izmir Turkey

Backgrounds Pulmonary arterial hypertension （PAH） was previously considered an illness that affects mostly the young, but now it is also increasingly recognized in the elderly. The aim of this study was to compare the features of elderly versus younger patients diagnosed with PAH, and to define the prognostic factors which affect their long-term survival. Methods In this prospective, single center study, the clinical, echocardiographic, hemodynamic characteristics, and the outcomes of younger （18-65 years） and elderly （〉 65 years） patients with definitive diagnosis of precapillary PAIl were compared. Results A total of 119 patients were analyzed in this study; 43 were elderly （mean age： 71.5 ± 5.5 years）, while 76 were non-elderly （mean age 44.5 ±15.2 years）. During the mean follow-up duration of 26.8 ±25.0 months, 43 deaths occurred, 17 of which were among the elderly group, with 28 among non-elderly group. comparison of baseline parameters showed that 6 min walking distance, hemoglobin levels, pulmonary artery pressures and pulmonary vascular resistance were significantly lower; and estimated glomerular filtration rate, body mass index, E/e＇ and pulmonary capillary wedge pressure were significantly higher in the elderly group than in the younger group. Survival analysis demonstrated that the independent predictors of death were tricuspid plane annular systolic excursion （TAPSE; HR： 1.272, 95% cI： 1.079-1.499, P = 0.004） and uric acid （HR： 1.291, 95% cI： 1.042-1.600, P = 0.019） in the elderly group. In contrast, in the non-elderly group, higher brain natriuretic peptide （HR： 1.002, 95% cI： 1.001-1.004, P 〈 0.001） and higher right atrial pressure （HR： 1.128, 95% cI： 1.026-1.241, P = 0.013） values were the only parameters associated with mortality. conclusions Our data suggest that elderly PAH patients have a unique clinical and hemodynamic profile, with totally different prognostic markers compared to younger PAH patients.

关键词： clinical characteristics Prognosis Pulmonary hypertension The elderly

Urine products of bone breakdown as markers of bone resorption and clinical usefulness of urinary hydroxyproline:an overview

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chinese Medical Journal 2004年第2期17卷 291-295页

作者： baris Simsek zgülKaracaer inci Karaca Department of Oral and Maxillofacial Surgery Faculty of Dentistry University of Gazi Emek Ankara TurkeyDepartment of Oral and Maxillofacial Surgery Faculty of Dentistry University of Gazi Emek Ankara TurkeyDepartment of Prosthodontics Faculty of Dentistry University of Gazi Emek Ankara Turkey

Purpose The purpose of this study is to review the urine products of bone breakdown as markers of bone resorption and usefulness of urinary hydroxyproline.Data Related researches published in 1985 -2000 were systematically reviewed.Results Bone markers could be used for early diagnosis of bone metabolic diseases. Biochemical markers of bone resorption that reflect osteoclast activity and/or collagen degradation provide a new and potentially important clinical tool for the assessment and monitoring of bone metabolism. Assessment of bone resorption can be achieved with measurement of urinary hydroxylysine glycosides, urinary excretion of the collagen pyridinium cross-links, urinary excretion of type I collagen telopeptide breakdown products (cross-linked telopeptides) and urinary hydroxyproline.conclusion Urinary hydroxyproline has been in use as a marker of bone resorption, but it lacks sensitivity and specificity. It is a modified aminoacid that is a metabolic product of collagen breakdown. Hydroxyproline may be released either free or with fragments of the collagen molecule attached during bone resorption, and it is also liberated by the breakdown of complement and nonskeletal collagen.

关键词： bone resorption marker biochemical markers hydroxyproline collagen breakdown hydroxylysine glycosides pyrolidine deoxypyrolidine N-tebpeptides c-telopeptides

Effects of wheeled cable skidder on rut formation in skid trail-a case study in Hyrcanian forest

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Journal of Forestry Research 2011年第3期22卷 465-469页

作者： Meghdad Jourgholami baris Majnounian Department of Forestry and Forest Economics Faculty of Natural Resources University of Tehran P. O. Box 31585-4314 Karaj Iran

The impact of skidding operations on forest soils can be divided into three major categories： soil profile disturbance, soil compaction, and soil puddling and rutting. The present study was designed as a factorial experiment in the Kheyrud Forest with a Timberjack cable skidder to evaluate the influences of number of machine passes and soil moisture of skid trails on rutting over a fine-grained soil, and to quantify these effects. The effects of soil moisture of 20% 30%, 30% 40% and 40% 50% and different levels of compaction were studied. compaction treatments were applied using different numbers of skidding passes （1, 5, 10, 15, 20, 25, 30 times）. Result shows that an increase in the number of machine passes could increase rut depth, but the majority of rutting was occurred after the initial few machine passes. Also rut depth at soil moisture of 40% 50% was higher than rut depths at soil moisture of 30% 40% and 20% 30%. The average rut depth in soil with 20% 30%, 30% 40% and 40% 50% moisture was 17, 22 and 35 cm, respectively. Rut depths were increased significantly with soil moisture and number of machine passes. It is suggested that skidding operations should be planned when soil conditions are dry in order to minimize rutting., but if skidding must be done under wet conditions, the operations should be stopped when machine traffic could create deep ruts.

关键词： wheeled cable skidder rut formation disturbance soil moisture number of passes

Time-domain identification of One Noninteger Order Plus Time Delay models from step response measurements

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International Journal of Modeling, Simulation, and Scientific computing 2019年第1期10卷 155-176页

作者： baris Baykant Alagoz Aleksei Tepljakov Abdullah Ates Eduard Petlenkov celaleddin Yeroglu Department of computer Engineering Inonu University MalatyaTurkey Department of computer Systems Tallinn University of Technology TallinnEstonia

Practical performances of controller design methods strongly depend on relevancy of identified *** order system models promise advantage of more accurate modeling of real *** study presents a discussion on utilization of two fundamental numerical solution methods of fractional calculus in identification problems of One Noninteger Order Plus Time Delay with one pole(NOPTD-I)*** identification process is carried out by estimating parameters of a NOPTD-I type transfer function template so that the step response of the NOPTD-I model can sufficiently fit experimental step response *** the study,step responses of NOPTD-I models are numerically calculated according to two fundamental methods,which are Mittag-Leffler(ML)function and Grunwald-Letnikov(GL)*** swarm optimization(PSO)algorithm is used to perform data *** examples are presented to evaluate model parameter estimation performances of these two methods for synthetically generated noisy test *** experimental study is conducted for modeling pitch rotor of TRMS to compare experimental performances.

关键词： Model identification fractional-order systems Mittag-Leffler(ML)function Grunwald-Letnikov(GL)definition PSO

Fatty liver disease:Disparate predictive ability for cardiometabolic risk and all-cause mortality

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World Journal of Gastroenterology 2015年第48期21卷 13555-13565页

作者： Altan Onat Günay can Aysem Kaya Tugba Akbas Fatma Ozpamuk-Karadeniz baris Simsek Hakan cakir Hüsniye Yüksel Department of cardiology Cerrahpasa Medical FacultyIstanbul University Department of Public Health Cerrahpasa Medical FacultyIstanbul University Section of Biochemistry Institute of Cardiologyall Istanbul University Bagcilar Educational Hospital Balikligol State Hospital Department of cardiology S.Ersek Center for Cardiovascular Surgery Darica Farabi State Hospital

AIM: To assess the association of a surrogate of fatty liver disease(FLD) with incident type-2 diabetes, coronary heart disease, and all-cause ***: In a prospective population-based study on 1822 middle-aged adults, stratified to gender, we used an algorithm of fatty liver index(FLI) to identify associations with outcomes. An index ≥ 60 indicated the presence of FLD. In cox regression models, adjusted for age, smoking status, high-density lipoprotein cholesterol, and systolic blood pressure, we assessed the predictive value of FLI for incident diabetes, coronary heart disease(cHD), and all-cause ***: At a mean 8 year follow-up, 218 and 285 incident cases of diabetes and cHD, respectively, and 193 deaths were recorded. FLD was significantly associated in each gender with blood pressure, total cholesterol, apolipoprotein B, uric acid, and c-reactive protein; weakly with fasting glucose; and inversely with high-density lipoprotein-cholesterol and sex hormonebinding globulin. In adjusted cox models, FLD was(with a 5-fold HR) the major determinant of diabetes development. Analyses further disclosed significant independent prediction of cHD by FLD in combined gender [hazard ratio(HR) = 1.72, 95% confidence interval(cI): 1.17-2.53] and men(HR = 2.35, 95%cI: 1.25-4.43). Similarly-adjusted models for all-cause mortality proved, however, not to confer risk, except for a tendency in prediabetics and diabetic ***: A surrogate of FLD conferred significant high risk of diabetes and coronary heart disease, independent of some metabolic syndrome traits. Allcause mortality was not associated with FLD, except likely in the prediabetic state. Such a FLI may reliably be used in epidemiologic studies.

关键词： All-cause death coronary heart disease Hepatic steatosis Metabolic syndrome Turkish adultrisk factor study

Performance of Rc buildings after Kahramanmaraş Earthquakes: lessons toward performance based design

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 883-894页

作者： baris Binici Ahmet Yakut Koray Kadas Ozan Demirel Ugur Akpinar Afsin canbolat Firat Yurtseven Orkun Oztaskin Selin Aktas Erdem canbay Department of civil Engineering Middle East Technical UniversityAnkaraTurkey

Two simultaneous earthquakes occurred in the Kahramanmaraş-Pazarcık and Kahramanmaraş-Elbistan districts of Turkey on February 6,2023,and with magnitudes of 7.7 and 7.6,*** events caused the highest estimated loss recorded in Turkey within the last century from natural *** key reason for the extensive loss was the proximity of eleven cities to the earthquake *** East Technical University teams investigated the building sites in Gaziantep,Kahramanmaras,Hatay,Adiyaman and *** ground motion recordings revealed that in certain locations of Gaziantep,Kahramanmaraşand Hatay,the ground motion levels exceeded the maximum credible earthquake level defined for a return period of 2,475 years in the Turkish Earthquake *** building performance was investigated with respect to the construction year,which is a good indicator of compliance with modern seismic codes and inspection *** 97%of the collapsed buildings were constructed prior to 2000,whereas over 5,000 buildings,which were built after 2000,collapsed or required urgent *** of the buildings with minor or greater structural damage sustained heavy infill wall damage rendering occupancy *** from damage in older construction with significant structural deficiencies,the damage in some of the more recent and better constructed buildings was observed to be surprisingly *** can be attributed to the level of ground motion,significant ductility demands,poor material and workmanship and damage to non-structural *** the estimated total loss of above 100 billion dollars and over 50,000 casualties,the current seismic design criterion based on ductility and acceptance of structural damage should be re-evaluated to ensure a more resilient urban environment in high seismic regions.

关键词： earthquake damage Kahramanmaras earthquake Rc Building seismic codes poor performance

characteristics of the imaging diagnosis of alveolar echinococcosis

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World Journal of Gastrointestinal Surgery 2024年第9期16卷 2748-2754页

作者： Sonay Aydin baris Irgul Kemal Bugra Memis Volkan Kızılgoz Mecit Kantarci Department of Radiology Erzincan Binali Yıldırım UniversityFaculty of MedicineErzincan 24100Türkiye Department of Radiology Erzurum Ataturk UniversityErzurum 25000Türkiye

Alveolar echinococcosis(AE)primarily manifests in the liver and exhibits charac-teristics resembling those of slow-growing malignant *** Echino-coccus multilocularis infection can be *** infiltrating the vascular systems,biliary tracts,and the hilum of the liver,it might lead to various *** to its ability to infiltrate neighbouring tissues or metastasize to distant organs,AE can often be mistaken for *** present a concise overview of the epi-demiological and pathophysiological characteristics of AE,as well as the clinical manifestations of the *** article primarily examines the imaging charac-teristics of AE using various imaging techniques such as ultrasonography,com-puted tomography(cT),magnetic resonance imaging,diffusion-weighted ima-ging,and virtual non-enhanced dual-energy *** additionally examined the contribution of radiography in the diagnosis,treatment,and monitoring of the condition.

关键词： Alveolar echinococcosis Echinococcus multilocularis Virtual non-enhanced dual-energy computed tomography Percutaneous cyst drainage cyst infection Interven-tional radiology

Gastric carcinogenesis

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World Journal of Gastroenterology 2012年第37期18卷 5164-5170页

作者： Ismail Gomceli baris Demiriz Mesut Tez Department of Gastroenterologic Surgery Antalya Education and Research Hospital Department of General Surgery Ankara Numune Education and Research Hospital

Gastric cancer is the second most common cancer worldwide and the second most common cause of cancer-related deaths. Despite complete resection of gastric cancer and lymph node dissection, as well as improvements in chemotherapy and radiotherapy, there are still 700 000 gastric cancer-related deaths per year worldwide and more than 80% of patients with advanced gastric cancer die of the disease or recurrent disease within 1 year after diagnosis. None of the treatment modalities we have been applying today can influence the overall survival rates:at present, the overall 5-year relative survival rate for gastric cancer is about 28%. cellular metaplasia due to chronic inflammation, injury and repair are the most documented processes for neoplasia. It appears that chronic inflammation stimulates tumor development and plays a critical role in initiating, sustaining and advancing tumor growth. It is also evident that not all inflammation is tumorigenic. Additional mutations can be acquired, and this leads to the cancer cell gaining a further growth advantage and acquiring a more malignant phenotype. Intestinalization of gastric units, which is called "intestinal metaplasia"; phenotypic antralization of fundic units, which is called "spasmolytic polypeptide-expressing metaplasia"; and the development directly from the stem/progenitor cellzone are three pathways that have been described for gastric carcinogenesis. Also, an important factor for the development of gastrointestinal cancers is peritumoral stroma. However, the initiating cellular event in gastric metaplasia is still controversial. Understanding gastric carcinogenesis and its precursor lesions has been under intense investigation, and our paper attempts to highlight recent progress in this field of cancer research.

关键词： Gastric cancer cancer Stem cell carcino-genesis Oncogenesis Tumorigenesis