检索结果-南通市图书馆

Compression properties of cost-efficient porous expanded clay reinforced AA7075 syntactic foams fabricated by industrial-oriented die casting technology

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第1期21卷 60-70页

作者： İsmail cem Akgün Çağın Bolat Ali Gökşenli Faculty of Mechanical Engineering Istanbul Technical University34437İstanbulTurkey Faculty of Engineering Samsun University55420SamsunTurkey

In today’s manufacturing industries,hard competition between rival firms makes it compulsory for researchers to design lighter and cheaper machine components due to the megatrends of cost-effectiveness and *** this point,aluminum syntactic foams(ASFs)are new-generation engineering composites and come into the upfront as a *** to their features like low density,sufficient elongation,and perfect energy absorption ability,these advanced foams have been considerably seductive for many industrial sectors *** this study,an industrial-oriented automatic die casting technology was used for the first time to manufacture the combination of AA7075/porous expanded clay(PEC).Micro evaluations(optical and FESEM)reveal that there is a homogenous particle distribution in the foam samples,and inspections are compatible with the other ASF ***,T6 aging heat treatment was operated on one half of the produced foams to explore the probable impact of aging on the compressive *** results show that PEC particles can be an alternative to expensive hollow spheres used in the previous ***,a favorable relationship is ascertained between the aging treatment and mechanical properties such as compression strength and plateau strength.

关键词： die casting porous materials metal matrix sytanctic foams expanded clay compressive deformation

Multi-aspect analysis of ureteral access sheath usage in retrograde intrarenal surgery: A RIRSearch group study

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Urology 2024年第1期11卷 80-85页

作者： Oktay Özman Hacı M.Akgül cem Başataç Önder Çınar Eyüp B.Sancak Cenk M.Yazıcı Bülent Önal Haluk Akpınar Gaziosmanpasa Training and Research Hospital Urology ClinicİstanbulTurkey Tekirdağnamık Kemal University School of MedicineDepartment of UrologyTekirdağTurkey Group Florence nightingale Hospitals Department of UrologyİstanbulTurkey Zonguldak Bulent Ecevit University School of MedicineDepartment of UrologyZonguldakTurkey Çanakkale Onsekiz Mart University School of MedicineDepartment of UrologyÇanakkaleTurkey İstanbul University-Cerrahpaşa Cerrahpaşa Medical FacultyDepartment of UrologyİstanbulTurkey

Objective:To evaluate the effect of ureteral access sheath(UAS)use and calibration change on stone-free rate and complications of retrograde intrarenal surgery(RIRS).Methods:Data from 568 patients undergoing RIRS for kidney or upper ureteral stones were retrospectively ***,patients were compared after 1:1 propensity score matching,according to UAS usage during RIRS(UAS used[+]87 and UAS non-used[−]87 patients).Then all UAS+patients(n=481)were subdivided according to UAS calibration:9.5-11.5 Fr,10-12 Fr,11-13 Fr,and 13-15 *** outcomes of the study were the success and complications of ***:Stone-free rate of UAS+patients(86.2%)was significantly higher than UAS−patients(70.1%)after propensity score matching(p=0.01).Stone-free rate increased with higher caliber UAS(9.5-11.5 Fr:66.7%;10-12 Fr:87.0%;11-13 Fr:90.6%;13-15 Fr:100%;pns of UAS+patients(11.5%)were significantly lower than UAS−patients(27.6%)(p=0.01).Complications(8.7%)with 9.5-11.5 Fr UAS was lower than thicker UAS(17.2%)but was not statistically significant(p=0.09).UAS usage was an independent factor predicting stone-free status or peri-and post-operative complications(odds ratio[OR]3.654,95%confidence interval[CI]1.314-10.162;OR 4.443,95%CI 1.350-14.552;OR 4.107,95%CI 1.366-12.344,respectively).Conclusion:Use of UAS in RIRS may increase stone-free rates,which also increase with higher caliber *** usage may reduce complications;however,complications seemingly increase with higher UAS calibration.

关键词： Stone Retrograde intrarenal surgery Ureteral access sheath Urolithiasis Kidney

Effects of particle size,bimodality and heat treatment on mechanical properties of pumice reinforced aluminum syntactic foams produced by cold chamber die casting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2021年第6期18卷 529-540页

作者： Cagin Bolat Ismail cem Akgun Ali Goksenli Faculty of Mechanical Engineering Istanbul Technical University34437IstanbulTurkey

In recent years,metal matrix syntactic foams(MMSFs)have become highly attractive owing to their unique physical,microstructural and mechanical *** to their promising potential for different industrial areas like automotive,aviation,and defense,these advanced engineering materials can also be evaluated as serious alternatives to particle reinforced metallic composites and conventional metallic *** from previously reported laboratory scaled techniques in the literature,this experimental effort focuses on the feasibility of MMSF manufacturing via a fully automated and industrial-based cold chamber die casting ***,1-2 mm,2-4 mm,and bimodal(50vol.%)natural-based pumice filled aluminum syntactic foams were manufactured utilizing a purpose-made casting ***,macroscopic,and microscopic examinations show that all of the fabricated samples display perfect matrix/filler *** density levels of fabricated syntactic foams range between 1.50 and 1.80 g·cm^(-3) depending upon the pumice particles size *** assess mechanical responses,quasi-static compression tests were ***,half of the foam samples were subjected to heat treatment to explore possible influences of aging on the compressive features and damage *** indicate that although the heat treatment enhances the compressive strength,plateau stress,and energy absorption properties of the fabricated foams,it changes damage mode of the samples by causing brittle dominant deformation.

关键词： pumice cold chamber die casting syntactic foam bimodality damage characteristic

Clindamycin-induced acute cholestatic hepatitis

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2007年第40期13卷 5408-5410页

作者： cem Aygün Orhan Kocaman Yesim Gürbüz mer Sentürk Sadettin Hülagü Department of Gastroenterology Pathology Kocaeli University Medical FacultyKocaeli 41380Turkey

We report a case of acute hepatotoxicity in a 42-yearold woman after administration of clindamycin for a dental infection. After 6 d of treatment, she had fatigue, nausea, vomiting, anorexia, pruritus and jaundice. Her laboratory analysis showed alanine aminotransferase （ALT）, 1795 IU/L （normal range 0-40）; aspartate aminotransferase （AST）, 1337 IU/L （normal range 5-34）; alkaline phosphatase （ALP）, 339 IU/L （normal range 40-150）; 7-glutamyl transpeptidase （GGT）, 148 IU/L （normal range 9-64 IU/L）; total bilirubin, 4.1 mg/dL; direct bilirubin, 2.9 mg/dL and prothrombin time （PT）, 13.5 s, with international normalized ratio （InR）, 1.04. She was hospitalized, with immediate drug discontinuation. Her liver biopsy specimen showed mixed-type （both hepatocellular and cholestatic） hepatic injury, compatible with a diagnosis of drug-induced hepatitis. An objective causality assessment using the naranjo probability scale suggested that clindamycin was the probable cause of the acute hepatitis. In susceptible individuals, clindamycin use may lead to acute mixedtype liver toxicity. Complete recovery may be possible if the drug is discontinued before severe liver injury is established.

关键词： Clindamycin Hepatic injury Hepatitis

Protective effect of insulin and glucose at different concentrations on penicillin-induced astrocyte death on the primer astroglial cell line

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

neural Regeneration Research 2012年第24期7卷 1895-1899页

作者： Mehmet Bülent zdemir Hakan Aka agdas Erdogan Onur Tokgün Aydin Demiray Fenki Semin cem Becerir Department of Anatomy Pamukkale University School of MedicineDenizli 20070Turkey Department of Medical Biology Pamukkale University School of MedicineDenizli 20070Turkey Department of neurology Pamukkale University School of MedicineDenizli 20070Turkey Department of Endocrinology Turkish Health MinistryDenizli HospitalDenizli 20070Turkey Department of Pediatrics Pamukkale University School of MedicineDenizli 20070Turkey

Astrocytes perform many functions in the brain and spinal *** metabolism is important for astroglial cells and astrocytes are the only cells with insulin receptors in the *** common antibiotic penicillin is also a chemical agent that causes degenerative effect on neuronal *** aim of this study is to show the effect of insulin and glucose at different concentrations on the astrocyte death induced by penicillin on primer astroglial cell *** is well known that intracranial penicillin treatment causes neuronal cell death and it is used for experimental epilepsy model *** studies showed that insulin and glucose might protect neuronal cell in case of proper ***,the present study is about the effect of insulin and glucose against astrocyte death induced by *** this purpose,newborn rat brain was extracted and then mechanically dissociated to astroglial cell suspension and finally grown in culture *** were maintained for 2 weeks prior to being used in these *** concentrations of insulin（0,1,3 nM）and glucose（0,3,30 mM）were used in media without penicillin and with 2 500μM *** decreased the viability of astroglial cell *** highest cell viability appeared in medium with 3 nM insulin and 3 mM glucose but without ***,in medium with penicillin,the best cell survival was in medium with 1 nM insulin but without glucose. We concluded that insulin and glucose show protective effects on the damage induced by penicillin to primer astroglial cell ***,cell survival depends on concentrations of insulin and glucose *** results of this study will help to explain cerebrovascular pathologies parallel to insulin and glucose conditions of patient after intracranial injuries.

关键词： astrocyte penicillin insulin glucose rat newborn brain cell culture cell death cell survival

A micromirror array with annular partitioning for high-speed random-access axial focusing

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2020年第1期9卷 241-255页

作者： nathan Tessema Ersumo cem Yalcin nick Antipa nicolas Pegard Laura Waller Daniel Lopez Rikky Muller The University of California Berkeley and University of CaliforniaSan Francisco Graduate Program in BioengineeringBerkeleyCA 94720USA Department of Electrical Engineering&Computer Sciences University of CaliforniaBerkeleyCA 94720USA Department of Applied Physical Sciences University of North Carolina at Chapel HillChapel HillNC 27514USA Chan Zuckerberg Biohub San FranciscoCA 94158USA Physical Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20899USA

Dynamic axial focusing functionality has recently experienced widespread incorporation in microscopy,augmented/virtual reality(AR/VR),adaptive optics and material ***,the limitations of existing varifocal tools continue to beset the performance capabilities and operating overhead of the optical systems that mobilize such *** varifocal tools that are the least burdensome to operate(*** crystal,elastomeric or optofluidic lenses)suffer from low(≈100 Hz)refresh ***,the fastest devices sacrifice either critical capabilities such as their dwelling capacity(*** gradient lenses or monolithic micromechanical mirrors)or low operating overhead(*** mirrors).Here,we present a general-purpose random-access axial focusing device that bridges these previously conflicting features of high speed,dwelling capacity and lightweight drive by employing lowrigidity micromirrors that exploit the robustness of defocusing phase ***,the device consists of an 8.2mm diameter array of piston-motion and 48-μm-pitch micromirror pixels that provide 2πphase shifting for wavelengths shorter than 1100 nm with 10-90% settling in 64.8μs(i.e.,15.44 kHz refresh rate).The pixels are electrically partitioned into 32 rings for a driving scheme that enables phase-wrapped operation with circular symmetry and requiresnts demonstrated the array’s wide focusing range with a measured ability to target 29 distinct resolvable depth ***,the features of the proposed array offer the potential for compact,straightforward methods of tackling bottlenecked applications,including high-throughput single-cell targeting in neurobiology and the delivery of dense 3D visual information in AR/VR.

关键词： mirror axial random

Synergistic effect of multiple predisposing risk factors on the development of bezoars

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2012年第9期18卷 960-964页

作者： Metin Kement nuraydin Ozlem Elif Colak Sadik Kesmer cem Gezen Selahattin Vural Department of General Surgery Samsun Education and Research Hospital Department of General Surgery Kartal Education and Research Hospital

AIM： To describe the clinical characteristics of patients with gastric or intestinal bezoars recently treated in our hospital.

关键词： Bezoar Diospyrobezoars Persimmon Phyto-bezoar Trichobezoar

Can platelet count/spleen diameter ratio be used for cirrhotic children to predict esophageal varices?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Hepatology 2016年第33期8卷 1466-1470页

作者： Oya balci Sezer Deniz Celik nihal Tutar Figen Ozcay Department of Pediatric Gastroenterology Hepatology and NutritionBaskent University Department of Child Health and Diseases Baskent University Department of Radiology Baskent University

AIM To determine the laboratory and radiologic parameters, including the platelet count(PC)-to-spleen diameter(SD) ratio as a non-invasive marker that may predict the presence of esophageal varices(EV) in children with *** Eighty-nine patients with cirrhosis, but without a history of variceal bleeding were prospectively included. The children were grouped into 6-12 and 12-18 years of age groups. These groups were also divided into 2 subgroups(presence and absence of EV). All of the patients underwent a complete biochemical and radiologic evaluation. The PC(n/mm^3)-to-SD(mm) ratio was calculated for each patient. RESULTS Sixty-nine of 98(70.4%) patients had EV. The presence of ascites in all age groups was significantly associatedwith the presence of EV. There were no differences in serum albumin levels, PC, SD and the PC-to-SD ratio between the presence and absence of EV groups in both age groups(P > 0.05). COnCLUSIOn Laboratory and radiologic parameters, including the PC-to-SD ratio as a non-invasive marker(except for the presence of ascites), was inappropriate for detecting EV in children with cirrhosis.

关键词： Esophageal varices Variceal bleeding Platelet count-to-spleen diameter ratio Children

Mesenchymal stem cell therapy in patients with small bowel transplantation:Single center experience

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第25期20卷 8215-8220页

作者： Sait Murat Do?an Sel?uk K?l?n? Eyüp Kebap?? cem Tu?men Mustafa ?lmez Cezmi Karaca Alp Gürkan Ma?allah Baran Yusuf Kurtulmu? Organ Transplantation Center SB Tepecik Teaching and Research Hospital35121 Izmir Turkey Organ Transplantation Center Caml?ca University Hospital34360 IstanbulTurkey Department of Gastroenterology SB Tepecik Teaching and Research Hospital35121 IzmirTurkey Tissue Typing Laboratory SB Tepecik Teaching and Research Hospital 35121 Izmir Turkey

AIM: To study the effects of mesenchymal stem cell (MSC) therapy on the prevention of acute rejection and graft vs host disease following small bowel transplantation.

关键词： Short gut syndrome Small bowel transplantation Mesenchymal stem cells Acute rejection Stem cell therapy