110 research outputs found
Examination of the Relationship between Team (Group) Harmony and Role Perception among Players: A Research on Veteran National Players
AbstractThe purpose of the present study is examining the relationship between team (group) harmony and positive role perception. In addition, the present research aims at examining whether there are significant differences in players’ attitudes toward team (group) harmony and role perception in terms of age groups, gender, length of sporting, and country distributions. 29 female, 46 male; a total of 76 elite veteran players selected via random sampling method among elite veteran players who participated in international veteran friendly matches participated in the research. Questionnaire form that consists of three parts was used as the data collection tool of the present study. First part of the questionnaire form includes 4 questions about the players’ personal information; Group Environment Questionnaire developed by Carron et al. (1985) is the second part of the questionnaire; and Role Perception Scale developed by Beauchamp et al. (2002) is the third part of the questionnaire. According to research findings; there are significant differences in players’ team (group) harmony and role perception levels in terms of age groups, gender, length of sporting and country distributions (p<0.005). Research findings revealed a positive significant correlation between team (group) harmony and positive role perception at 0.01 significance level
Review on machining of additively manufactured nickel and titanium alloys
The machining of nickel and titanium-based superalloy components is very expensive and involves unusually high lead times compared with other engineering metals such as steels and aluminum. This has led to the development of most suitable additive manufacturing (AM) processes to fabricate these difficult-to-machine metals into near-net shape parts, thereby reducing the lead time and material waste, and significantly increasing productivity. Nonetheless, finish machining is still required on the AMed metal components to meet the dimensional and surface requirements of the application. Several research studies have investigated the machinability of AMed nickel and titanium alloy workpieces and have compared the results with the machining responses of wrought counterparts, which is detailed in this review. The categorization of the literature is based on the machining operations including turning, milling, drilling, and non-conventional machining, and the observations are discussed in accordance with various input parameters such as workpiece characteristics (hardness, microstructures) and anisotropy in mechanical properties due to build orientations during the AM process. Moreover, the influence of these parameters on cutting forces and temperatures, chip formation, and tool wear is analyzed and reported. From this review, it is found that the machinability of AMed nickel and titanium workpieces is quite different to the machining responses of their wrought counterparts. Further thorough experimentation is required to develop optimized machining parameters for AMed metal parts, while an exploration of different cutting tool geometries, coolant, and lubrication strategies for enhanced tool performance for machining AMed workpieces is essential. Finally, this study reviews the state of contemporary research, and offers suggestions for future research
Machining-induced surface integrity in brass alloys
This study presents machining process and resulting surface integrity properties of brass alloys including leaded (CW617N), low-leaded (CW511L) and lead-free (CW724R). Experimental data on cutting forces and cutting temperatures are presented to assess machining of these alloys. Surface quality, subsurface microhardness and microstructures of machined brass alloys are considered to assess surface integrity properties. Higher subsurface deformation was observed in low-leaded and lead-free brass materials compared to leaded brass materials. This present study reveals that machining process results in deformation twinning on the surface and subsurface of specimens. The role of machining parameters on performance measures and surface integrity aspects is also presented in this work. This work illustrates that machining parameters have a notable effect on measured machinability outputs. It should be noted that lead content has a strong influence on surface integrity aspects including microhardness and twinning of machined brass alloys
Improving the Surface Quality and Mechanical Properties of Selective Laser Sintered PA2200 Components by the Vibratory Surface Finishing Process
This paper attempts to improve the physical and mechanical properties of selective laser sintered polyamide PA2200
components through a vibratory surface finishing process by inducing severe plastic deformation at the outer surface
layers. The industrial target of additive manufacturing components is to obtain structures having surface roughness,
hardness, and other mechanical properties equivalent to or better than those produced conventionally. Compared to
the as-built SLS PA2200 samples, vibratory surface finishing treated specimens exhibited a smooth surface microstructure
and more favorable roughness, hardness, and tensile strength. Also, the duration of the vibratory surface finishing
process showed a further improvement in the surface roughness and hardness of the SLS samples. Compared to the asbuilt
state, the roughness and hardness of the surface-treated samples improved by almost 90% and 15%, respectively.
Consequently, microstructural analysis indicates that lower surface roughness and enhanced surface hardness is a crucial
factor in influencing the overall tensile strength of SLS-PA2200 components. We consider that the combination of VSF
and SLS processes can successfully handle a wide range of potential applications. This study also highlights the efficiency
and applicability of the vibratory surface finishing process to other additive manufacturing processes and materials
G6PD S218F Mediterranean mutation frequency in children with glucose-6-phosphate dehydrogenase deficiency
AMAÇ: Glukoz-6-fosfat dehidrogenaz (G6PD) enzim eksikliği olan çocuklarda G6PD S218F Akdeniz mutasyonunun görülme sıklığını belirlemek.
GEREÇ ve YÖNTEM: Adnan Menderes Üniversitesi Tıp Fakültesi Çocuk Hematolojisi ve Neonatoloji Bilim Dalları'nda 2004-2012 yılları arasında G6PD enzim eksikliği tanısı alan, enzim düzeyi düşük saptanan (<6 U/grHb) ve mutasyon çalışması yapılmış olan hastalar dahil edildi. Enzim düzeyi kantitatif spektrofotometri yöntemi ile, mutasyon analizi lightcycler 1.5 real-time PCR cihazında melting-curve analizi ile yapıldı.
BULGULAR: G6PD enzim eksikliği anemisi tanısı konulan 60 hastanın, 29'u yenidoğan sarılığı (YDS), 31'i favizm nedeniyle başvurdu. Hastaların 44'ü erkek (%73,3), 16'sı (%26,7) kız; favizm tanısı konulan olguların 27'si (%87) erkek, 4'ü (%13) kız; yenidoğan sarılığı olgularının 17'si (%58) erkek, 12'si (%41,3) kız idi. Favizm
tanısı konulan 31 olgunun 30'unda halsizlik, 28'inde sarılık ve 22'sinde kusma yakınması mevcuttu. Bakla yedikten sonra semptomların görülmesi arasında geçen süre ortalama 6 saat (dağılım, 2-24 saat) idi. Yenidoğan
döneminde sarılık ile başvuran olguların üçünde patolojik sarılık, 16'sında uzamış sarılık öyküsü mevcuttu. Dört bebeğe hiperbilirubinemi nedeniyle kan değişimi yapıldı. G6PD eksikliği saptanan 60 olgunun 15'inde (%25) homozigot, 6'sında (%10) heterozigot olmak üzere 21 hastada (%35) G6PD S218F Akdeniz mutasyonu tespit
edildi. Mutasyon saptanan olguların 13'ünde (%42) favizm, 8'inde (%27) yenidoğan sarılığı mevcuttu. Homozigot mutasyon saptanan 15 hastanın 1'si (%6,6) kız, 14'ü (%93) erkekti (p<0.001). G6PD S218F heterozigot mutasyonu saptanan 6 hastanın hepsi kızdı. Homozigot mutasyon saptanan olguların 4'ü YDS, 11'i bakla yeme sonrası sarılık; heterozigot mutasyon saptanan olguların ise 4'ü YDS, ikisi bakla yeme sonrası sarılık
yakınmasıyla başvurdu.G6PD S218F mutasyon görülme sıklığı açısından favizm ve yenidoğan sarılığı arasında istatistiksel olarak anlamlı fark saptanmadı (P=0.130).
SONUÇ: Çalışmamızda G6PD S218F Akdeniz mutasyonu sıklığını %35 olarak saptadık. Bu oran ülkemizdeki diğer çalışmalarda belirtilen oranlardan (%53-80) düşüktü. Bu durum bölgesel farklılıklara bağlı olabileceği gibi çalışmalardaki olgu sayılarının ve olgu özelliklerinin farklılığından da kaynaklanabilir. Akdeniz mutasyonu dışındaki diğer mutasyonların DNA dizi analizi ile saptanması bölgemizin özelliklerini daha iyi yansıtacaktır.OBJECTIVE: To determine the incidence of Mediterranean glucose-6-phosphate dehydrogenase (G6PD) S218F mutation.
MATERIALS and METHODS: Were included G6 PD deficiency cases whose enzyme level <6 with mutation analysis, and diagnosed between 2004-2012 at neonatology and pediatric hematology department in Adnan Menderes University Hospital. G6PD activity was determined by quantitative spectrohotometry and mutations
were analyzed with LighCycler 5.1 real-time PCR melting-curve analysis.
RESULTS: Totaly 60 patients with the diagnosis of G6PD deficiency anemia admitted to hospital; 29 have neonatal jaundice and 31 have favizm. 44 patients (73.3%) were male, 16(26.7%) were female; favizm cases diagnosed 27(87%) patients were male and 4 (13%) were females. 17 cases of neonatal jaundice(58%) were male
and 12(41.3%) were female. In 28 of 31 patients diagnosed with favizm have fatigue, 30 patients have jaundice and 22 have vomiting. The average time between the occurance of symptoms after eating fava is 6 hours (range, 2-24 hours). Three patients who presented with jaundice in neonatal period had pathological jaundice, 16 patients
had a history of prolonged jaundice. Exchange transfussion was applicated to 4 patients with hyperbilirubinemia. Totaly in 21 patients (35%) G6PD deficiency has been detected; 15 patients (25%) were homozygous, 6(10%) patient were heterozygous of G6PD Mediterranean S218F mutation was detected. Mutations detected in 13(42%)
favizm, 8(27%) patients had neonatal jaundice. 1 of 15 patients with homozygous mutation (6.6%) were female and 14(93%) were male (p<0.001). All 6 patients with G6PD mutation S218F heterozygous were female. 4 of homozygous mutation detected patients had neonatal jaundice, 11 had jaundice after eating beans, 4 of patients
with heterozygous mutations had neonatal jaundive, and 2 had jaundice after eating bean. There is nostastistically difference between G6PD S218F mutation incidence of favizm and neonatal jaundice in the newborns (p=0.13)
CONCLUSION: We determined the incidence of mutations in G6PD Mediterranean S218F as 35%. This ratio is lower than the other investigations in our country with the ratio of 53-80%. This situation may be due to regional differences in the number of cases and case studies, such as caused by differences in characteristics. DNA sequence analysis of mutations other than the detection of mutations in the mediterrannean region determination
better reflect the characteristics of our region
Cardiac tumors in a tertiary care cancer hospital: clinical features, echocardiographic findings, treatment and outcomes
Cardiac tumors are a rare entity, comprised of tumors with diverse histology and natural history. We report the clinical characteristics, echocardiograhic findings, therapy and outcome of 59 patients with primary and metastatic cardiac tumors. Our institutional echocardiogram data base from 1993 through 2005 was reviewed to identify patients diagnosed with intra-cardiac tumor. A total of 59 patients with cardiac tumors were identified and included in the study. The patients' characteristics, presenting symptoms, diagnostic tests, location, histology of the tumor, treatment and the one year survival rate of this population was collected from the medical records. Of the 59 cardiac tumor cases, 16 (27%) were primary cardiac tumors and 43 (73%) were secondary cardiac tumors. The most common primary tumor was sarcoma affecting 13 (81%) of the 16 cases. Of these, 5 patients were angiosarcoma, 5 unclassified sarcoma, one myxoid sarcoma and 2 malignant fibrous histiocytoma. The mean age at presentation was 41.1 years, and the most common location was right atrium affecting 6 cases (37.5%). The most common symptom of dyspnea was present in 10 (62.5%) cases. Eleven (25.6%) of the 43 secondary cardiac tumors were metastasis from renal cell carcinoma. The mean age at presentation was 55.4 years. Right atrium was the most frequent location affecting 18 (42%) of the 43 patients. The most common presenting symptom was dyspnea in 15 (35%) cases. For both primary and secondary tumors, dyspnea was the most common symptom and right atrium was most frequently involved. Sarcoma was the most common primary cardiac tumor while metastasis from renal cell carcinoma was the most common secondary tumor
Development and mechanical modeling of Si1-XGex/Si MQW based uncooled microbolometers in a 130 nm BiCMOS
This paper presents the development of process integration and mechanical modeling of a Si1-xGex/Si MQW based uncooled micro-bolometer. The recent progress on layer transfer based integration scheme of Si1-xGex/Si based micro-bolometer into a 130 nm BiCMOS process is presented. The two important parts of the process integration, namely the layer-transfer and stress compensation of the arms are studied. The initial successful results on layer transfer and the FEM modeling for the stress compensation of the thin and narrow arms of the bolometer is presented. Finally, the developed FEM model is compared with the fabricated cantilevers. The results show that the developed FEM model has a very good matching with the experimental results; thus very convenient to use for the FEM modeling of the full bolometer structure
Impact of nitrogen and climate change interactions on ambient air pollution and human health
Relationships between internal and external information systems integration, cost and quality performance, and firm profitability
The effect of material parameters on chip formation in orthogonal cutting simulation of Ti-5553 Alloy
It is a well-known fact that Titanium alloys are commonly used materials in various industries, in particular aerospace and biomedical applications. Among titanium alloys, Ti-5553 is a new generation high temperature near beta alloy. As it has superior properties such as high tensile strength and fatigue life, it has a potential to be used in aerospace industries for structural components to replace Ti-6Al-4V. This study provides investigation on the effect of material parameters including material model parameters and frictional conditions on simulating chip formation in orthogonal cutting process of this alloy. Experimental data are used to compare forces, contact length, and to predict chip form in the cutting process of Ti-5553 alloy. This study illustrates that with calibrated frictional condition and critical damage value, it is possible to predict forces, contact length and chip morphology that can show good agreement with experimental data. (C) 2017 The Authors. Published by Elsevier B.V
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