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Journal of geriatric Cardiology 2024年第7期21卷 768-774页

作者： Mustafa Ebik muhammet g.rdoğan UğurÖzkan Department of Cardiology Edirne SultanMurat State HospitalEdirneTurkey Department of Cardiology School of MedicineTrakya UniversityEdirneTurkey

The COVID-19 outbreak in late 2019 was declared a pandemic by the World Health Organization(WHO)on March 12,2020.[1]As of the latest WHO data,COVID-19 has caused over 770 million cases and nearly 7 million deaths worldwide.[2]Hospitalizations due to COVID-19 are correlated with advanced age.[3,4]According to re-ports,individuals over the age of 65 account for 80%of COVID-19-related deaths.[3,4]This is primar-ily due to the increased burden of comorbidity with age.

关键词： infected patients mortality

The evolving landscape of biliary tract cancers:comparing French and US National Comprehensive Cancer Network guidelines

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Hepatobiliary Surgery and Nutrition 2024年第5期13卷 850-853页

作者： muhammet Ozer Ilyas Sahin Department of Medical Oncology Dana Farber Cancer InstituteHarvard Medical SchoolBostonMAUSA Division of Hematology/Oncology Department of MedicineUniversity of FloridaGainesvilleFLUSA University of Florida Health Cancer Center GainesvilleFLUSA

Biliary tract cancers(BTCs)constitute a heterogeneous group of hepatobiliary malignancies originating along the biliary *** up to 20%of primary hepatobiliary tumors consist of BTCs(1).The primary risk factors include cholelithiasis,chronic inflammatory diseases of the bile ducts,non-alcoholic steatohepatitis(NASH),liver cirrhosis,tobacco use,and chronic viral hepatitis B and C infections(2).

关键词： Clinical practice biliary tract cancers(BTCs) French guidelines National Comprehensive Cancer Network guidelines(NCCN guidelines)

Cooperative THz communication for UAVs in 6g and beyond

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green Energy and Intelligent Transportation 2024年第1期3卷 25-31页

作者： Nazifa Mustari muhammet Ali Karabulut A.F.M.Shahen Shah Ufuk Tureli Department of Electronics and Communication Engineering Yildiz Technical UniversityTurkey Department of Electrical Electronics Engineering Faculty of Engineering and ArchitectureKafkas UniversityKarsTurkey

One of the key components of any smart city is considered to be its intelligent transportation systems(ITSs).Unmanned aerial vehicles(UAVs)are envisioned in several ITS application fields because of their autonomous operation,mobility,communication/processing capabilities,and other *** this paper,cooperative terahertz(THz)communication is proposed for flying ad hoc networks(FANETs),which is a particular kind of network made up of a collection of small UAVs linked in an ad hoc fashion and working together to accomplish high-level *** frequency spectrum for wireless communication has been expanding continuously in order to meet the demand for *** the forthcoming 6g and beyond,communications in the THz range will be vital,similar to how mmWave-band communications are currently influencing the 5g of wireless mobile *** finite state machine(FSM)of the proposed cooperative communication system for THz band is presented.A Markov chain model-based analytical study is carried out,which derives relationships among ***,numerical results are provided to support the analytical study.

关键词： Cooperative MAC THz UAVs 6g

Role of vitamin D in COVID-19 and other viral infections

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World Journal of Virology 2024年第3期13卷 10-25页

作者： muhammet Mesut Nezir Engin ÖnerÖzdemir Private Outpatient Clinic of Child Follow-up Academy Sakarya 54050Türkiye Division of Allergy and Immunology Department of PediatricsSakarya Research and Training HospitalSakarya UniversityFaculty of MedicineSakarya 54100Türkiye

Vitamin D is a steroid hormone that is naturally produced in the body or obtained through dietary sources,primarily under the influence of UVB *** essential nutrient has a vital role in numerous physiological processes,encom-passing immune function,cell growth,differentiation,insulin regulation,and cardiovascular well-being,along with its pivotal role in sustaining the delicate equilibrium of calcium and phosphate concentrations in the ***,vitamin D reinforces mucosal defense and bolsters the immune system through immunomodulation,making it a critical component of overall *** studies have unveiled the profound connection between vitamin D and the predisposition to respiratory tract infections,including well-known viruses such as influenza and the novel severe acute respiratory syndrome coronavirus ***-min D deficiency has been consistently linked to increased severity of coronavirus disease 2019(COVID-19)and a heightened risk of mortality among afflicted *** observational studies have further substantiated these findings,indicating that levels of vitamin D are linked with both the occurrence and severity of COVID-19 *** D has its influence on viral infections th-rough a multitude of mechanisms,such as promoting the release of antimicrobial peptides and fine-tuning the responses of the immune ***,vitamin D is intertwined with the intricate network of the renin–angiotensin system,suggesting a potential impact on the development of complications related to *** further clinical trials and extensive research are warranted,the existing body of evidence strongly hints at the possible use of vitamin D as a valuable tool in the prophylaxis and management of COVID-19 and other viral infectious diseases.

关键词： COVID-19 SARS-CoV-2 Vitamin D Influenza virus Viral infections

Constant frequency operation of parallel resonant converter for constant-current constant-voltage battery charger applications

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 186-199页

作者： Taha Nurettin güCIN muhammet BIBEROgLU Bekir FINCAN Energy Systems Engineering Department University of Yalova Electrical Engineering Department Istanbul Technical University

This paper proposes a design and control approach to parallel resonant converter(PRC) based battery *** proposed approach is particularly suitable for the constant-current constant-voltage(CC-CV)charging method, which is the most commonly utilized *** the PRC is operated at two different frequencies for each CC and CV charging modes, this approach eliminates the need for complicated control techniques such as the frequency-control and *** proposed method not only simplifies the design and implementation processes of the converter unit but also simplifies the design of output filter configuration and decreases the number of the required components for the control of the *** proposed method is confirmed by two experimental *** results show that the designed charger circuit ensured a very stable constant current in CC charging phase, where the charging current is fixed to 1.75 *** a voltage increase in CV phase is observed, the charger circuit is able to decrease the charging current to 0.5 A in CV phase, as depicted in battery *** efficiency of the charger is figured out to be in the range of 86%-93% in the first setup, while it is found to be in the range of 78%-88% in the second setup,where a high frequency transformer is employed.

关键词： Resonant converter Parallel resonant converter Battery charger Constant-current constant-voltage(CC-CV)charging

Seed,germination,and seed-reserve traits differ along an altitudinal gradient

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Journal of Forestry Research 2022年第6期33卷 1903-1912页

作者： muhammet Tonguç Sercan Önder Nesrin gülcemal Fatih Tonguç Faculty of Agriculture Department of Agricultural BiotechnologyIsparta University of Applied Sciences32260 IspartaTurkey Faculty of Forestry Department of Forest EngineeringIsparta University of Applied Sciences32260 IspartaTurkey

Turkish red pine(P inus brutia Ten.), an important pine species for afforestation studies, grows at a wide range of altitudes in the eastern Mediterranean area. Seeds from low(0–400 m a.s.l.), mid(400–800 m) and high(800–1000 m) altitudinal gradients were collected to assess the effects of these gradients on morphological traits(seed length, seed width, 100-seed weight), germination variables(germination percentage and mean germination time), and 10biochemical variables related to seed reserves. Relationships among these variables were examined with a correlation analysis. Seeds from low and high altitudes had significantly higher 100-seed weight, higher percentage germination but longer germination times and higher total oil and reducing sugars contents. Seeds from mid altitudes had higher carotenoid and soluble phenolics contents. Among the examined biochemical variables, only flavonoid content did not differ among the altitude gradients. The main fatty acids in seeds samples(linoleic, oleic, palmitic and stearic acids) were also influenced by the altitude gradients. Oil and total reducing sugars contents were positively correlated with germination percentage, and carotenoid content was negatively correlated with germination percentage. Our results confirmed that seed and germination variables, including the reserve composition varied significantly among the altitudinal gradients.

关键词： Elevation germination Pine Seed Seed reserves

Investigating the performance of passageway corridor for ground reinforced embankments against rockfall

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Journal of Mountain Science 2023年第1期20卷 15-30页

作者： muhammet Çelik Civil Engineering Department Faculty of EngineeringYalova UniversityYalova77200Türkiye

Rockfall disasters can result in damages to various structures such as highways and *** reinforced embankments(gRE) are one of the barrier types used to prevent rockfall. gRE absorb the impact energy of the hitting rock blocks by the movement of fine soil particles triggered by the penetration of the rock in the soil. In this process,stresses in the wall are distributed in both the transverse and longitudinal directions. gREs on the valley slopes can be hundreds of meters long, so such structures cause difficulty in transition to valley slope behind the embankments. Especially, access to areas such as agricultural, pasture or forest lands behind the gRE becomes a challenge. The current paper presents the design of passageways in gRE using the finite element method to provide safe corridors at several different parts within the hundreds of meters long structures. A total of 4 different passageway designs for gRE were developed. Each finite element model was subjected to rockfall with different kinetic energies of 500, 1000 and 3000kJ. The obtained results showed that 44% increase in structure volume increased the impact capacity from 500 kJ to ***, the critical displacement caused by rockfall impact with an energy of 3000 kJ was reduced by 31%. It was determined that the support applied with the reinforced concrete wall did not reach the desired energy absorption value due to its rigid structure, and even collapsed at 3000 kJ.

关键词： Disaster Rockfall ground reinforced embankments Finite elements Transportation

Influence of Al-B grain refiner on porosity formation of directionally solidified Al-Si alloys

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China Foundry 2020年第5期17卷 372-377页

作者： muhammet Uludağ Bursa Technical University Metallurgical and Materials Engineering DepartmentBursaTurkey

This work aims to present a perspective for porosity formation in three different alloys:A356,A413 and A380.1 by taking into account the addition of Al-B grain refiners:AlTi5B1 and *** directional solidification method was used,and microstructural changes of the alloys and its correlation with porosity formation were *** size,number of pores,average pore length and distribution of pores were statistically ***,external shrinkage was examined,and the volume of external shrinkage was *** was found that there was a relationship between external shrinkage and the size and number of *** the size and number of pores internally decrease,external shrinkage ***,porosity is decreased in all the three Al-Si alloys when Al-B grain refiners are *** distribution of pore diameters is low when AlTi5B1 is *** refiners have a different effect on porosity formation of Al-Si alloys with regard to their solidification morphology.

关键词： Al-Si alloys directional solidification grain refinement internal porosity external shrinkage

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Applied Mathematics and Mechanics(English Edition) 2004年第5期25卷 587-594页

作者： muhammet Yürüsoy Department of Mechanical Education Faculty of Technical Education Ahmet Necdet Sezer Campus Afyon Kocatepe University

Two dimensional equations of steady motion for third order fluids are expressed in a special coordinate system generated by the potential flow corresponding to an inviscid fluid. For the inviscid flow around an arbitrary object, the streamlines are the phi-coordinates and velocity potential lines are psi-coordinates which form an orthogonal curvilinear set of coordinates. The outcome, boundary layer equations, is then shown to be independent of the body shape immersed into the flow. As a first approximation,assumption that second grade terms are negligible compared to viscous and third grade terms. Second grade terms spoil scaling transformation which is only transformation leading to similarity solutions for third grade fluid. By using Lie group methods,infinitesimal generators of boundary layer equations are calculated. The equations are transformed into an ordinary differential system. Numerical solutions of outcoming nonlinear differential equations are found by using combination of a Runge-Kutta algorithm and shooting technique.

关键词： boundary layer equation Lie group third grade fluid

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Applied Mathematics and Mechanics(English Edition) 2004年第4期25卷 467-474页

作者： muhammet Yürüsoy Department of Mechanical Education Faculty of Technical Education Afyon Kocatepe University

The two dimensional equations of motions for the slowly flowing and heat transfer in second grade fluid are written in Cartesian coordinates neglecting the inertial terms. When the inertia terms are simply omitted from the equations of motions the resulting solutions are valid approximately for Re1. This fact can also be deduced from the dimensionless form of the momentum and energy equations. By employing Lie group analysis, the symmetries of the equations are calculated. The Lie algebra consists of four finite parameter and one infinite parameter Lie group transformations, one being the scaling symmetry and the others being translations. Two different types of solutions are found using the symmetries. Using translations in x and y coordinates, an exponential type of exact solution is presented. For the scaling symmetry, the outcoming ordinary differential equations are more involved and only a series type of approximate solution is presented. Finally, some boundary value problems are discussed.

关键词： creeping flow heat transfer Lie group