145 research outputs found
Türkiye İstanbul İlinde Yetiştirilen İtalyan Orijinli Manda Sürülerinde Farklı Modeller ile Laktasyon Eğrilerinin Karşılaştırılması
This study was aimed to investigate biometry of lactation curve for Italian origined water buffalo in Istanbul province of Turkey. Total 72 heads Italian origined water buffalo were used at first lactation and three calving seasons as animal material. Wood, Wilmink and Cobby and Le Du models were chosen in this study. The general average lactation length, total lactation milk yield average and average daily milk yield were found 234 days, 1607.4 kg and 6.86 kg, respectively. Determination coefficient was calculated for Wood, Wilmink and Cobby and Le Du models for summer calving season as 0.94, 0.92 and 0.93, respectively. Wood model was found the highest coefficient of determination in general. Moreover, persistency (S) and maximum milk yields (Ymax) for Wood model were calculated. These values were found as 5.89 and 9.76 for first lactation in general group, respectively. Finally, this study is showed that the Wood model has the best fitted model among all models for all groups for first lactation for Italian origined water buffalo,Bu çalışmada Türkiye’de İstanbul ilinde yetiştirilen İtalyan orijinli mandalarda laktasyon eğrilerinin biyometrisi araştırılması amaçlanmıştır. Hayvan materyali olarak üç malaklama mevsiminde ve ilk laktasyonda olan 72 baş İtalyan orijinli manda kullanılmıştır. Sunulan çalışmada Wood, Wilmink ve Cobby ve Le Du modelleri seçilmiştir. Genel ortalama laktasyon süresi, toplam süt verim ortalaması ve günlük ortalama süt verimi sırasıyla 234 gün, 1607,4 kg ve 6.86 kg olarak bulunmuştur. Yazın malaklayan hayvanlarda Wood, Wilmink ve Cobby ve Le Du modelleri için belirleme katsayıları sırasıyla 0.94, 0.92 ve 0.93 olarak bulunmuştur. Genel olarak Wood modeli en yüksek belirleme katsayısına sahip olmuştur. Bunun yanında, Wood modeli için persistens (S), maksimum süt verimi (Ymax) değerleri hesaplanmıştır. Bu değerler ilk laktasyon için sırasıyla 5.89 ve 9.76 olarak bulunmuştur. Sonuç olarak çalışma göstermiştir ki ilk laktasyondaki İtalyan orijinli mandalarda tüm gruplar için diğer modeler içinde en iyi uyum Wood modelinde görülmüştür
SU2 REAL GAS MODELS’ PERFORMANCE PREDICTIONS ON A COLD GAS THRUSTER
Soğuk gaz itki sistemleri 1960’lı yıllardan bu yana özellikle uyduların yörünge kontrolünde tercih edilen sistemler
olmuşlardır.Yakıt tankındaki yüksek basıncın görev süresince azalması nedeniyle, tank içindeki yakıtta oldukça düşük
sıcaklıklar gözlenmektedir. Ayrıca itici lülesinin çıkışında da, vakuma yakın basınçlara genleşen yakıtın sıcaklığı
oldukça düşmektedir. Bu koşullar altında, itki sisteminin performansının tasarım sürecinde gerçekçi olarak tahmin
edilebilmesi için, açık kaynaklı, sıkıştırılabilir akışkanlar için uygun bir hesaplamalı akışkanlar dinamiği aracı olan
SU2
’nun kullanılması kararlaştırılmıştır. Bu çalışmada, itki sisteminin doğası gereği karşılaşılan düşük sıcaklık ve
basınç etkilerinin doğru modellenebilmesi adına, SU2
’nun ideal gaz, van-der Waals ve Peng-Robinson gaz modelleri
kullanılarak elde edilen performans tahminleri ile itici vakum odası performans test sonuçları karşılaştırılmıştır. İtici
performans testleri için bu amaçla kurulan termal vakum odası test alt yapısı kullanılmıştır. İtici simulasyonları ve
performans testleri, yakıt tankının nominal ve düşük sıcaklıkta koşulladırıldığı durumlar için yürütülmüştür. Elde edilen
veriler, SU2 van der Waals gaz modelinin, her iki sıcaklık koşulunda da vakum odası performans testlerine en yakın
sonuçları verdiğini göstermektedir
Assessment of teachers' perceptions of organizational citizenship behaviors and psychological empowerment: An empirical analysis in Turkey
Organizational citizenship behaviors (OCM) are discretionary individual behaviors that are not directly recognized by the reward system, but in the aggregate promote the overall effectiveness and functioning of the organization. Scholarly concern in OCB has increased dramatically over the past two decades. Nevertheless, there are significant research gaps and key issues yet to he addressed. Furthermore, employee empowerment can be conceptualized as the symbolic construction of the personal state of employees characterized by competence, or the skill and ability to perform effectively, and control, or the authority and autonomy to act. The main purpose of our study is to measure of organizational citizenship behaviors and psychological empowerment on teachers.This empiric research is planned to be realized by surveying method. Teachers in province Bursa have been reached and asked to participate in the study. We reached to 332 participants. The survey instrument included organizational citizenship behaviors, psychological empowerment and demographic questions about the participants. (C) 2013 The Authors. Published by Elsevier Ltd
Computational Modeling of Vehicle Radiators Using Porous Medium Approach
A common tool for the determination of thermal characteristics of vehicle radiators is the experimental testing. However, experimental testing may not be feasible considering the cost and labor-time. Basic understanding of the past experimental data and analytical/computational modeling can significantly enhance the effectiveness of the design and development phase. One such computational modeling technique is the utilization of computational fluid dynamics (CFD) analysis to predict the thermal characteristics of a vehicle radiator. However, CFD models are also not suitable to be used as a design tool since considerable amount of computational power and time is required due to the multiple length scales involved in the problem, especially the small-scale geometric details associated with the fins. Although fins introduce a significant complexity for the problem, the repetitive and/or regular structure of the fins enables the porous medium based modeling. By porous modeling, a memory and time efficient computational model can be developed and implemented as an efficient design tool for radiators. In this work, a computational methodology is described to obtain the hydrodynamic and thermal characteristics of a vehicle radiator. Although the proposed methodology is discussed in the context of a vehicle radiator, the proposed methodology can be implemented to any compact heat exchanger with repetitive fin structures which is an important problem for many industrial applications
Kartezyen hesaplama ağları kullanılarak iki boyutlu sıkıştırılabilir akışlar için laminar navier-stokes çözücüsü geliştirilmesi
TÜBİTAK MAG01.05.201
Kartezyen Hesaplama Ağları Kullanılarak Üç Boyutlu Sıkıştırılabilir Akışlar için Navier-Stokes Çözücüsü Geliştirilmesi
TÜBİTAK MAG Proje01.06.2017Bu proje çerçevesinde Kartezyen hesaplama ağları için üç boyutlu bir Navier-Stokes çözücüsü geliştirilmiştir. Hesaplama ağının üretimi ile akış alanının çözümü aşamaları arasında gerekli olan kullanıcı müdahalesini ortadan kaldırmak üzere geliştirilecek yazılımın tam otomatik olarak gerçekleştirilmiştir. Akış alanındaki gövdenin geometrisi yapısal olmayan üçgen elemanlar kullanılarak üç boyutlu bir yüzey hesaplama ağı şeklinde verildiğinde, gövde uyumlu (body-fitted) üçgen prizma elemanlardan oluşan hesaplama ağı gövde geometrisinin şişirilmesiyle otomatik olarak oluşturulmaktadır. Daha sonra, gövde uyumlu hesaplama ağı, çözüm alanının sınırlarını tanımlayan bir kök hücrenin eşit hücrelere bölünmesi ile elde edilen Kartezyen hesaplama ağının içerisine yerleştirilmektedir. Her iki hesaplama ağının arasında kalan bölge dört yüzlü tetrahedral elemanlarla doldurulmaktadır. Navier-Stokes denklemlerinin sonlu hacim formülasyonu hücre merkezli yaklaşımla kullanılmaktadır. Hücre yüzlerindeki akılar akı fark ayrıştırması ve akı vektör ayrıştırması yöntemleriyle hesaplanmaktadır. Uzayda ikinci dereceden doğruluk elde edilebilmesi için basit değişkenlerin yeniden oluşturulmasında (reconstruction) yol tümleme (path integration) ve asgari kareler (least squares) yöntemleri kullanılmaktadır. Doğru ve sınırlı değerler elde edilebilmesi için yeniden oluşturma işlemi sırasında limitleyiciler kullanılmaktadır. Türbülans modeli olarak ise literatürde mevcut modellerden bir denklemli SpalartAllmaras türbülans modeli ile iki denklemli k-e ve k-w türbülans modellerinden yararlanılmaktadır. Yakınsamanın hızlandırılabilmesi için yerel zaman adımlarıyla birlikte çok kademeli (multistage) zaman adımlaması kullanılmaktadır. Çözüme bağlı hesaplama ağı adaptasyonu çözüm ile ağ arasındaki uyumun oluşmasını sağlayarak, akıştaki kritik bölgelerin daha iyi çözümlenmesine olanak sağlamaktadır. Çözüm adaptasyonu kayma tabakalarında hız dönümü, normal ve oblik şoklarda ise hız gradyanı kullanılarak gerçekleştirilmektedir. Geliştirilen yazılım NACA 0012 ve ONERA M6 kanadı etrafındaki üç boyutlu akış için test edilmiş ve elde edilen sayısal sonuçlar literatürde mevcut deneysel sonuçları ile karşılaştırılarak doğrulanmıştır
Tibial torus and toddler's fractures misdiagnosed as transient synovitis: a case series
<p>Abstract</p> <p>Introduction</p> <p>The high incidence of transient synovitis in early childhood makes it the first suspected pathology in a limping child. Trauma, which has long been regarded as a causative factor for transient synovitis, may be underestimated in a non-cooperative toddler.</p> <p>After excluding most serious conditions, such as septic arthritis, a speculative diagnosis of transient synovitis can be made, and this can easily mask a subtle musculoskeletal injury.</p> <p>Case presentations</p> <p>We report the cases of three Caucasian patients (two boys, aged 20-months- and three-years-old, and one girl, aged two-years-old), with tibial torus and toddler's fractures which were late-diagnosed due to an initial misdiagnosis of transient synovitis of the hip.</p> <p>Conclusion</p> <p>In a non-cooperative child musculoskeletal trauma can be mistaken as a simple causative factor for transient synovitis of the hip and this can easily prevent further investigation for a possible subtle musculoskeletal injury of the lower extremities.</p> <p>Our experience with the presented cases suggests the need to be more vigilant in the differential diagnosis of transient synovitis in young children.</p
A comparative ID migraine screener study in ophthalmology, ENT and neurology out-patient clinics
Migraine is more likely to be misdiagnosed in patients with comorbid diseases. Not only primary care physicians, but also specialists might misdiagnose it due to the lack of diagnostic criteria awareness. The ID migraine test is a reliable screening instrument that may facilitate and accelerate migraine recognition. This study aimed to compare the prevalence and characteristics of migraine in a large sample of patients admitted to clinics of ophthalmology (OC), ear, nose and throat diseases (ENTC) and neurology (NC), as well as to validate the use of the ID migraine test in OC and ENTC settings. This was a multicentre (11 cites) study of out-patients admitting either to NC, ENTC or OC of the study sites during five consecutive working days within 1 week. From each of the clinics, 100 patients were planned to be recruited. All recruited patients were interviewed and those having a headache complaint received an ID migraine test and were examined for headache diagnosis by a neurologist, blinded to the ID migraine test result. A total of 2625 subjects were recruited. Only 1.3% of OC patients and 5.4% of ENTC patients have been admitted with a primary complaint of headache, whereas the percentage of NC patients suffering from headache was 37.6%. Whereas 138 patients (19.3%) in OC, 154 (17.3%) in ENTC and 347 (34%) in NC were found to be ID migraine test positive, 149 patients (20.8%) in OC, 142 (16%) in ENTC and 338 (33.1%) in NC were diagnosed with migraine. The sensitivity, specificity, and positive and negative predictive ratios of the ID migraine test were found to be similar in all clinics. An important fraction of the patients admitted to NC, as well as to OC and ENTC, for headache and/or other complaints were found out to have migraine by means of a simple screening test. This study validated the ID migraine test as a sensitive and specific tool in OC and ENTC, encouraging its use as a screening instrument.Pfizer-Türkiy
Vaccination in Individuals with Multiple Sclerosis – Part I
Multiple sclerosis (MS) is an autoimmune and demyelinating disease of the central nervous system. It is a chronic disease, and in the evaluation of all other health and vital processes, decisions should be made by considering the disease process and the drugs used by the patient. Since vaccination can be performed at every stage of life, from childhood to adulthood, immune system activity, except where it is characteristic of the vaccine, should be reviewed in patients with MS. In this review, the applications of different vaccines in individuals with MS are discussed in two separate sections
Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
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