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A novel indicator system for catalytic spectrophotometric determination and speciation of inorganic selenium species (Se(Ⅳ), Se(Ⅵ)) at trace levels in natural lake and river water samples

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Rare Metals 2011年第5期30卷 477-487页

作者： Ramazan Gürkan Halil brahim Ulusoy mehmet akay Pinar Bulut Department of Chemistry Faculty of Science University of Cumhuriyet

A novel catalytic kinetic method is proposed for the determination of Se（Ⅳ）, Se（Ⅵ）, and total inorganic selenium in water based on the catalytic effect of Se（Ⅳ） on the reduction of Celestine blue by sodium sulfide at pH 7.0 phosphate buffer. The fixed-time method was adopted for the determination and speciation of inorganic selenium. Under the optimum conditions, the two calibration graphs are linear with a good correlation coefficient in the range 2-20 and 20-200 μg·L-1 of Se（Ⅳ） for the fixed-time method at 30℃. The experimental and theo- retical detection limits of the developed kinetic method were found to be 0.21 and 2.50 μg·L-1 for the fixed-time method （3 min）. All of the variables that affect the sensitivity at 645 nm were investigated, and the optimum conditions were established. The interference effect of various cations and anions on the Se（Ⅳ） determination was also studied. The selectivity of the selenium determination was greatly improved with the use of the strongly cation exchange resin such as Amberlite IR120 plus as long as chelating agents of thiourea and thiosulphate. The proposed kinetic method was validated statistically and through recovery studies in natural water samples. The relative standard deviations （RSDs） for ten replicate measurements of 2, 10, and 20 μg·L-1 of Se（Ⅳ） change between 0.35% and 5.58%, while the RSDs for ten replicate measurements of 3, 6, and 12 μg·L-1 of Se（Ⅵ） change between 0.49% and 1.61%. Analyses of a certified standard reference material （NIST SRM 1643e） for selenium using the fixed-time method showed that the proposed kinetic method has good accuracy. The Se（Ⅳ）, Se（Ⅵ）, and total inorganic selenium in lake and river water samples have been successfully determined by this method after selective reduction of Se（Ⅵ） to Se（Ⅳ）.

关键词： selenium speciation Celestine blue catalytic effect kinetic spectrophotometry natural waters

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Robust Backstepping Control of a Quadrotor Unmanned Aerial Vehicle under Colored Noises

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Computers, Materials & Continua 2025年第1期82卷 777-798页

作者： mehmet Karahan Electrical and Electronic Engineering Department Atilim UniversityAnkara06830Turkey

Advances in software and hardware technologies have facilitated the production of quadrotor unmanned aerial vehicles(UAVs).Nowadays,people actively use quadrotor UAVs in essential missions such as search and rescue,counter-terrorism,firefighting,surveillance,and cargo *** performing these tasks,quadrotors must operate in noisy ***,a robust controller design that can control the altitude and attitude of the quadrotor in noisy environments is of great *** researchers have focused only on white Gaussian noise in their studies,whereas researchers need to consider the effects of all colored noises during the operation of the *** study aims to design a robust controller that is resistant to all colored ***,a nonlinear quadrotormodel was created with ***,a backstepping controller resistant to colored noises was *** backstepping controller was tested under Gaussian white,pink,brown,blue,and purple *** and Lyapunov-based controller designswere also carried out,and their time responses(rise time,overshoot,settling time)were compared with those of the backstepping *** the simulations,time was in seconds,altitude was in meters,and roll,pitch,and yaw references were in *** and settling time values were in seconds,and overshoot value was in *** the obtained values are examined,simulations prove that the proposed backstepping controller has the least overshoot and the shortest settling time under all noise types.

关键词： Backstepping control colored noises Gaussian noise Lyapunov stability quadrotor robustness PID control

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Differences in individual susceptibility affect the development of trigeminal neuralgia

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Neural Regeneration Research 2013年第14期8卷 1337-1342页

作者： Yusuf Kurtulus Duransoy Mesut Mete Emrah akay mehmet Seluki Department of Neurosurgery Celal Bayar University School of Medicine Clinic of Neurosurgery Anamur State Hospital

Trigeminal neuralgia is a syndrome due to dysfunctional hyperactivity of the trigeminal nerve, and is characterized by a sudden, usually unilateral, recurrent lancinating pain arising from one or more divisions of the nerve. The most accepted pathogenetic mechanism for trigeminal neuralgia is compression of the nerve at its dorsal root entry zone or in its distal course. In this paper, we report four cases with trigeminal neuralgia due to an unknown mechanism after an intracranial intervention The onset of trigeminal neuralgia after surgical interventions that are unrelated to the trigeminal nerve suggests that in patients with greater individual susceptibility, nerve contact with the vascular structure due to postoperative pressure and changes in cerebrospinal fluid flow may cause the onset of pain.

关键词： neural regeneration peripheral nerve injury asymptomatic vascular compression of the cranialnerves cranial nerves dorsal root entry zone dorsal root exit zone etiology hyperactivedysfunction syndrome individual susceptibility risk factors trigeminal neuralgia neuroregeneration

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Protein adsorption, cell viability and corrosion properties of Ti6Al4V alloy treated by plasma oxidation and anodic oxidation

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1269-1280页

作者： ÖzgüBayrak Hojjat Ghahramanzadeh Asl ayşe ak Department of Mechanical Engineering Erzincan Binali Yıldırım UniversityErzincan 24100Turkey Department of Mechanical Engineering Karadeniz Technical UniversityTrabzon 61080Turkey Vocational School of Health Services Medical Imaging Techniques ProgrammeKocaeli UniversityKocaeli 41001Turkey

The hardness,wettability,and electrochemical properties of Ti6Al4V alloy surfaces treated with anodic oxidation and plasma oxidation as well as the viabilities of the different cell lines on the obtained surfaces were *** anodic oxidation was performed for 10 min under 100 V potential,and it resulted in a 0.95μm thick nanoporous anatase-TiO2 *** the other hand,plasma oxidation was carried out at 650℃ for 1 h and resulted in a dense rutile-TiO2 structure with a thickness of 1.2μ*** a hardness of HV0.025823 and roughness of^220 nm were obtained by plasma oxidation,those obtained by anodic oxidation were HV0.025512 and^130 nm,*** anodic oxidation process created a more hydrophilic surface with a contact angle of 87.2°.Both oxidation processes produced similar properties in terms of corrosion behavior and showed better resistance than the as-received state in a certain range of ***,the surface treatments led to no significant change in the protein adsorption levels,which indicates that the difference in viability between the osteoblast and fibroblast cells was not due to the difference in surface protein *** all the factors,the surfaces obtained by anodic oxidation treatment revealed higher cell viability than those obtained by plasma oxidation(p=0.05).

关键词： Ti6Al4V oxidation corrosion cell viability protein adsorption

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Hematological profile of COVID-19 infected children before and after the spread of the Omicron variant in Istanbul

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Asian Pacific Journal of Tropical Medicine 2022年第12期15卷 551-557页

作者： Berkin Berk akbeyaz ayŞe Karaaslan CerenÇetin mehmet Tolga Köle Zeynep AltaŞ Yasemin akın Department of Pediatrics University of Health SciencesKartal Dr.Lütfi Kirdar City HospitalPediatric Hematology and Oncology IstanbulTurkey Department of Pediatric Infectious Diseases University of Health SciencesKartal Dr.Lütfi Kirdar City HospitalIstanbulTurkey Department of Pediatrics University of Health SciencesKartal Dr.Lütfi Kirdar City HospitalIstanbulTurkey Department of Public Health Marmara UniversityIstanbulTurkey

Objective:To examine the effect of the COVID-19 virus,especially the Omicron variant,on hematological parameters of hospitalized pediatric patients during the COVID-19 ***:Medical records of pediatric COVID-19 patients hospitalized at Kartal Dr.Lütfi K?rdar City Hospital in Istanbul,Turkey,between March 2020 and May 2022 were retrospectively reviewed to analyze data regarding demographics,SARS-Co V-2 infection polymerase chain reaction(PCR)test results,reversetranscriptase(RT)-PCR for other respiratory agents,duration of hospital stay,and hematological and biochemical laboratory ***:Out of 467 children with a confirmed diagnosis of SARSCo V-2 infection,94(20.1%)had Omicron infection and 373(79.9%)were infected with other variants;the Omicron group had younger patients than the remaining samples(P<0.001).The most frequent clinical symptoms in all children were cough(53.5%)and fever(32.3%),followed by vomiting(20.8%).Lung involvement in the Omicron group(10.6%)was significantly lower than in the remaining samples(29.8%)(P<0.001).Hemoglobin and lymphocyte levels were lower in the Omicron-infected group(both P<0.001),while prothrombin time,activated partial thromboplastin time,international normalized ratio,and D-dimer levels were significantly higher in this group(P<0.001,P<0.001,P<0.001,and P=0.023,respectively).In terms of lung involvement,those with lung involvement were significantly older(P<0.001).Conclusions:Although lung involvement was less common with Omicron infection,this group had greater hematological system involvement,such as anemia,lymphopenia,D-dimer elevation,and coagulation disorders.

关键词： COVID Children Omicron Hematologic findings

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Human bocavirus infection in children hospitalized with lower respiratory tract infections:Does viral load affect disease course?

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Asian Pacific Journal of Tropical Medicine 2022年第8期15卷 354-360页

作者： ayşe Karaaslan CerenÇetin Serap Demir Tekol Ufuk Yükselmiş mehmet Tolga Köle Yasemin akın Department of Pediatric Infectious Diseases University of Health SciencesKartal Dr.Lütfi Kırdar City HospitalIstanbulTurkey Department of Microbiology University of Health SciencesKartal Dr.Lütfi Kırdar City HospitalIstanbulTurkey Department of Pediatric Intensive Care Unit University of Health SciencesKartal Dr.Lütfi Kırdar City HospitalIstanbulTurkey Department of Pediatrics University of Health SciencesKartal Dr.Lütfi Kırdar City HospitalIstanbulTurkey

Objective:To examine the effects of human bocavirus type 1(HBoV1)on the course of lower respiratory tract infections in cases of monoinfection and coinfection,and the effects of HBoV1 viral load on the disease in children under six years old hospitalized with a diagnosis of HBoV1-associated lower respiratory tract ***:Children under six years of age,who were hospitalized with the diagnosis of lower respiratory tract infection due to HBoV1 between 1 January 2021 and 1 January 2022 were included in the *** confirmation of the respiratory pathogens was performed using polymerase chain reaction(PCR).Results:Fifty-four(16.4%)children with HBoV1 among 329 children whose PCR was positive with bacterial/viral agent in nasopharyngeal swab samples were included in the *** were 28(51.9%)males and 26(48.1%)females with a median age 23.4 months[interquartile range(IQR):13.2,30.0 months](min-max:1 month-68 months).HBoV1 was detected as a monoinfecton in 26(48.1%)children,and as a coinfection with other respiratory agents in 28 children(51.9%).In multiple regression analysis,coinfection(P=0.032)was associated with the length of hospitalization(Pay and need for intensive *** was found to affect the length of hospitalization.

关键词： Human bocavirus Lower respiratory tract infection Children Viral load

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Improvements in quality of life in septuagenarians versus octogenarians undergoing trans-catheter aortic valve replacement

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Journal of Geriatric Cardiology 2016年第5期13卷 439-443页

作者： Nuray Kahraman ay Yasin ay Osman Sonmez mehmet akif Vatankulu Omer Goktekin Department of Cardiology Bezmialem Vakif University Fatih Istanbul Turkey Department of Cardiovascular Surgery Bezmialem Vakif University Fatih Istanbul Turkey

Background Very elderly patients represent a distinct patient group in clinical setting in terms of a decision for trans-catheter aortic valve replacement （TAVR） when one considers the potential improvement in the quality of life （QoL） on one hand and the benefit to risk ratio on the other. This study aimed to compare functional and QoL outcomes of TAVR between octogenarians and septuagenarians. Methods This prospective cohort study included 136 elderly patients （70 to 89 years of age）, who tmderwent Wansfemoral TAVR due to degenerative aortic stenosis. Patients were allocated into one of the following age groups： septuagenarians （n = 67） and octogenarians （n = 69）. Preoperative and early postoperative clinical parameteT：s were recorded. In addition, QoL of the patients was evaluated using SF-36 questionnaire preoperatively and six month postoperatively. Results Groups were similar in terms of early postoperative mortality and morbidity parameters. The mean New York Heart Association （NYHA） class improved after TAVR in both groups. In addition, all SF-36 norm-based scale and SF-36 summary scale scores improved significantly in both groups during the postoperative period. Postoperatively, physical functioning, general health and physical component summary scores were significantly better in the septuagenarian group （P = 0.02, 0.01, 0.03, respectively）. ConcLusion Although the improvement in the QoL in terms of physical health was more marked in septuagenarians than in octogenarians, substantial benefits on the QoL and particularly on mental health seem to justify re-consideration of TAVR indications in the very elderly.

关键词： Elderly Octogenarians Quality of life Septuagenarian Trans-catheter aortic valve replacement

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Aerodynamics of non-slender delta and reverse delta wings:Wing thickness,anhedral angle and cropping ratio

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Chinese Journal of Aeronautics 2023年第4期36卷 79-91页

作者： Göktug KOCak mehmet Metin YAVUZ Turkish Aerospace Industries Inc.Aerodynamics Chief Engineer at TF-XProjectAnkara 06980Turkey Mechanical Engineering Department Middle East Technical UniversityAnkara 06800Turkey

The effects of thickness-to-chord(t=c)ratio,anhedral angle(d),and cropping ratio from trailing-edge(Cr%)on the aerodynamics of non-slender reverse delta wings in comparison to non-slender delta wings with sweep angle of 45°were characterized in a low-speed wind tunnel using force and pressure *** measurements were conducted for total of 8 different delta and reverse delta *** different t/c ratios of 5.9%and 1.1%,and two different anhedral angles ofd=15°and 30°for non-cropped and cropped at Cr=30%conditions were *** results indicate that the reverse delta wings generate higher lift-to-drag ratio and have better longitudinal static stability characteristics compared to the delta *** wing thickness has favorable effect on longitudinal static stability for the reverse delta wing whereas longitudinal static stability is not influenced by wing thickness for the delta *** reverse delta wings,the anhe-draled wing without cropping has adverse effect on aerodynamic performance and decreases the lift-to-drag *** in anhedraled wing causes significant improvement in lift-to-drag ratio,shift in aerodynamic and pressure centers towards the trailing-edge,and enhancement in longitudi-nal static stability.

关键词： Aerodynamic coefficients Anhedral Cropping Leading-edge vortex Longitudinal static stability Non-slender delta wing Non-slender reverse delta wing Stall Three-dimensional surface separation

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A Late Cretaceous ensimatic arc developed during closure of the northern branch of Neo-Tethys(central-northern Turkey)

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Geoscience Frontiers 2019年第3期10卷 1015-1028页

作者： Metin Beyazpirin? Ali Ekber ak?ay Ali Yilmaz Meftun Kerem S?nmez Geological Research Department General Directorate of Mineral Research and Exploration (MTA) Department of Environmental Engineering Engineering Faculty Cumhuriyet University

Studies on differentiation of ensimatic arc units from melange units in the Northern Anatolian Ophiolitic Belt(NAOB) are very rare. The study area represents the southern edge of the central part of the *** aim of the study is to distinguish the main units of NAOB and to define the geotectonic setting of the Darmik Ensimatic Arc Association(DEAA). To study the ensimatic arc units as an independent tectonic unit is important and facilitates understanding of the geological evolution of the NAOB. During field studies, the contact relationships within the Darmik Ensimatic Arc Association(DEAA) units and also with other tectonic units were reviewed. Then, paleontological, geochronological, petrological and also geochemical properties of the DEAA have been defined. In the present study, ensimatic arc units have been distinguished from ophiolitic association for the first time, in the region. As a result of the study, the DEAA is divided into two levels and lower level named as the Kartal unit and upper level named as the izibüyük unit. In the Kartal unit, basaltic and andesitic lavas with their equivalent pyroclastic rock units are dominant. Radiolarite and mudstones interbedded within the Kartal unit of DEAA have Turonian and Santonian age. In addition, the age of basalt samples of DEAA are 98.7 ± 2.4 Ma, defined using the^(40)Ar/39 Ar method. The izibüyük unit of DEAA comprises conglomerate, sandstone, claystone, mudstone,clayey limestone, micritic limestone with volcanic interbeds and also calciturbidites. Santonian-Maastrichtian ages were obtained from this unit of the DEAA. In conclusion, the age of DEAA is widely accepted as Late Cretaceous. After the evaluation of the analysis, the volcanics of the DEAA originated from calcalkaline-basalts, which reflect ensimatic arc magmatism.

关键词： North Anatolian Ophiolitic Belt Double subduction zones Darmik ensimatic arc Turkey

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Crescentic glomerulonephritis in children:a single centre experience

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World Journal of Pediatrics 2016年第2期12卷 225-230页

作者： Sare GülfemÖzlü aysunÇaltık Özlem aydoğ mehmet Bülbül Gülay Demircin EvrimÇakıcı Nilüfer Arda ayşeÖner Department of Pediatric Nephrology Dr Sami Ulus Childrens and Maternity HospitalAnkaraTurkey Department of Pathology Sami Ulus Childrens and Maternity HospitalAnkaraTurkey

Background:Crescentic glomerulonephritis(CsGN)is characterized by crescents in 50%or more of glomeruli and clinically by a sudden and progressive decline in renal ***:We evaluated the etiology,clinical features,prognostic factors and long-term outcome of *** January 2000 and December 2010,45 children(26 girls,19 boys)with biopsy-proven CsGN(>50%crescents)were investigated ***:The mean age of the patients was 130.86±33.77 *** mean duration of symptoms prior to diagnosis was 26±12 days(4-40 days).Most of the children had hypertension(62.2%),macroscopic hematuria(73.3%),oligoanuria(44.4%),edema(51.1%)and purpuric rash(40%)at *** final clinical status of the patients was complete remission(n=21),partial remission(n=5)or chronic kidney disease(n=19).Adverse outcomes were significantly associated with a long duration between the onset of symptoms and treatment(P=0.038),the presence of oligoanuria(P=0.006),a severe decreased glomerular filtration rate(GFR75%)(P=0.03),and the ratio of fi brous crescents(P=0.015).Conclusion:The outcome of CsGN in children continues to be poor,and it should be treated as a renal emergency.

关键词： glomerulonephritis renal biopsy renal failure

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