A phase-field model for fracture of unidirectional fiber-reinforced polymer matrix composites

This study presents a crack phase-field approach for anisotropic continua to model, in particular, fracture of fiber-reinforced matrix composites. Starting with the variational formulation of the multi-field problem of fracture in terms of the deformation and the crack phase fields, the governing equations feature the evolution of the anisotropic crack phase-field and the balance of linear momentum, presented for finite and small strains. A recently proposed energy-based anisotropic failure criterion is incorporated into the model with a constitutive threshold function regulating the crack initiation in regard to the matrix and the fibers in a superposed framework. Representative numerical examples are shown for the crack initiation and propagation in unidirectional fiber-reinforced polymer composites under Mode-I, Mode-II and mixed-mode bending. Model parameters are obtained by fitting to sets of experimental data. The associated finite element results are able to capture anisotropic crack initiation and growth in unidirectional fiber-reinforced composite laminates

Improving ship maintenance : a criticality and reliability approach

Ship maintenance has evolved through the years incorporating tools and techniques already applied in other industrial sectors. The obvious benefits from such an application include improved safety, environmental protection, asset integrity, minimisation of downtime and increased operability. In this paper, a predictive maintenance approach is described employing reliability and criticality analysis tools. Its application on the Diesel Generator (DG) system of a motor cruise ship is also presented. Well known tools such as Failure Modes, Effects and Criticality Analysis (FMECA) and Fault Tree Analysis (FTA) using static and dynamic gates together with reliability Importance Measures (IMs) are applied. The results of this research paper include the estimation of the reliability of the main system and sub-systems and the identification of their critical components as well as suggesting measures in order to prevent and/or mitigate the failures of the under-performing equipment

Identification of clinical and simple laboratory variables predicting responsible gastrointestinal lesions in patients with iron deficiency anemia

Iron deficiency anemia (IDA) is a frequent disorder. Also, it may be a sign of underlying serious diseases. Iron deficiency points to an occult or frank bleeding lesion when occurred in men or postmenopausal women. In this study, we aimed to evaluate the diagnostic yield of endoscopy in patients with IDA and to define predictive factors of gastrointestinal (GI) lesions causing IDA. Ninety-one patients (77 women, 14 men; mean age: 43 years) who were decided to have esophago-duodenoscopy and/or colonoscopy for iron deficiency anemia were interviewed and responded to a questionnaire that included clinical and biochemical variables. The endoscopic findings were recorded as GI lesions causing IDA or not causing IDA. Endoscopy revealed a source of IDA in 18.6 % of cases. The risk factors for finding GI lesions causing IDA were as follows: male gender (p= 0.004), advanced age (> 50 years) (p= 0.010), weight loss (over 20% of total body weight lost in last 6 month) (p= 0.020), chronic diarrhea (p= 0.006), change of bowel habits (p= 0.043), epigastric tenderness (p= 0.037), raised carcinoembryonic antigen (CEA) level (normal range: 0-7 ng/mL) (p= 0.039), < 10 gr/dl hemoglobin (Hb) level (p=0.054). None of these risk factors had been present in 21 (23%) women younger than 51 years. In this group, no patient had any GI lesion likely to cause IDA (negative predictive value= 100%). In multivariate analysis, advanced age (p=0.017), male gender (p< 0.01) and weight lost (p=0.012) found that associated with GI lesions in all patients. It may be an appropriate clinical approach to consider these risk factors when deciding for gastrointestinal endoscopic evaluation in iron deficiency anemia

Bazı Antidepresan ve Antiepileptik İlaçların İnsan Kanında Eş Zamanlı Analizi için LC-MS/MS Yöntemi Geliştirilmesi

Bu çalışmada, sık kullanılan antidepresan ilaç etken maddeleri olan Paroksetin, Sitolapram, Essitolapram, Venlafaksin ile antiepileptik ilaç etken maddeleri olan Karbamazepin ve Oxkarbamazepin moleküllerinin tayini için, insan kanında Sıvı Kromatografisi-Kütle Spektrometresi (LC-MS/MS) cihazı ile basit, hızlı ve güvenilir olan bir metot geliştirilmiştir. Her bir ilaç etken maddesi için geri kazanım, doğruluk, yüzde bağıl standart sapma (%RSD), gözlenebilme sınırı (LOD) ve alt tayin sınırı (LOQ) gibi bazı analitik parametrelerin belirlenip, ölçülebilir en düşük değerlerin yüksek hassasiyet ile en kısa sürede eş zamanlı olarak yapılması amaçlanmıştır. Etken maddelerin her biri için belirlenen konsantrasyonlarda; LOD değerleri 0,06-0,36 ng.mL-1, LOQ değerleri ise 0,21-1,21  ng.mL-1 aralığında elde edilmiştir. Gün içi tekrarlanabilirlik değerlerinde %RSD sonuçları 0,15-10,71 ng.mL-1, günler arası tekrarlanabilirlik değerlerinde ise %RSD sonuçları 0,23-13,75 ng.mL-1 aralığında bulunmuştur

Chemerin as a marker of subclinical cardiac involvement in psoriatic patients

Background: Chemerin has been associated with psoriasis and inflammation, but there are no studies demonstrating an association between chemerin and subclinical cardiac involvement in psoriatic patients. Therefore, the present study aimed to evaluate whether psoriatic patients with increased epicardial fat tissue, impaired flow-mediated dilatation, and diastolic dysfunction have higher serum chemerin levels than a healthy control group. Methods: The study included 60 psoriatic patients and 32 healthy controls. Echocardiographic parameters, epicardial fat tissue, flow-mediated dilatation, and chemerin levels were recorded for both groups. Results: The serum levels of chemerin in the psoriatic patients were significantly higher than in the control group. The diastolic function parameters, including isovolumic contraction and relaxation time, E’/A’ (early diastolic mitral annular velocity/late diastolic mitral annular velocity), and E/E’ (early diastolic peak velocity of mitral inflow/early diastolic mitral annular velocity) values, differed significantly between the groups. Epicardial fat tissue was significantly higher and flow-mediated dilatation was significantly lower in psoriatic patients than in the controls. Chemerin was significantly positively correlated with age, body mass index, systolic and diastolic blood pressures, waist circumference, E/E’, and epicardial fat tissue. Serum chemerin was significantly negatively correlated with E’, E’/A’, and flow-mediated dilatation. A multiple linear regression analysis showed that chemerin was independently correlated with E/E’. Conclusions: Psoriatic patients exhibit early subclinical atherosclerosis and diastolic dysfunction. Chemerin can be used as a marker to screen for patients with subclinical cardiac involvement

Rumeli Kazaskerliği 376 numaralı defterin transkript ve hukuki tahlili

Bir devletin hukuk sisteminin ne olduğunu tespit edebilmek için o hukuk sisteminin temelini teşkil eden hukuk mevzuatını ve bunların uygulama örnekleri olan mahkeme kararlarını incelemek gerekir.Hukuk sistemini ve adli teşkilat yapısını İslâm hukuku üzerine kuran Osmanlı Devleti'nde şer'iye mahkemeleri, yargı faaliyetinin bel kemiğini teşkil etmiştir. XV. yy.ın ikinci yarısından devletin sona ermesine kadar geçen yaklaşık 5 asırlık süre içerisinde, insanlar arasında meydana gelen hukuki uyuşmazlıklar dil, din ve renk ayrımı yapılmaksızın çözüme kavuşturulurken, yapılan yargılama belli usul ve prensipler çerçevesinde kayıt altına alınmıştır. Kadıların vermiş oldukları ilam, hüccet ve görevleri gereği tuttukları çeşitli kayıtları içeren bu belgelere en çok kullanılan ismiyle "şer'iye sicilleri" denir. Osmanlı Devleti'nin son 500 yılının hukuki, iktisadi, askeri, idari ve sosyal kurumlarına ışık tutacak olan şer'iye sicilleri sadece birer mahkeme defteri olmadığından günümüzdekilerle kıyaslamak doğru bir sonuca götürmeyebilir. Şer'iye sicilleri, ait oldukları devrin adeta tarih aynasıdır. Her il ve ilçe merkezindeki şer'iye sicilleri, o bölgenin en kuvvetli ve güvenilir tarih kaynaklarıdır. Sadece genel Osmanlı tarihi için değil mahallî tarihler için de şer'iye sicillerinin birinci derecede bir bilgi kaynağı olduklarında şüphe yoktur.Şu anda ülkemizde halen el atılmamış binlerce şer'iye sicili bulunmaktadır. Gerek genel tarihimizin gerekse de hukuk tarihimizin daha sağlam bir zemine oturabilmesi için bu defterlerin akademik düzeyde ele alınıp günışığına çıkarılması gerekmektedir. Biz bu yüksek lisans tezi çalışmamız ile bu defterlerden birisini mercek altına aldık. Elde ettiğimiz bilimsel verilerden bazılarının bilinenleri teyit ettiğini görürken bazılarının da hukuk dünyasına yeni bilgiler eklediğini müşahede ettik.To determine a state's law system, the law's subjects under discussion based the law system and the trial's desicions which are their application samples must be studied.The şeriye trials in Ottoman State which establish their law system and judicial organization structure on Islam rights constitute the main parts of judgement activity. From the second half of XV. century to the end of the state in approximately 5 century discords among people are solved without language, religion, and color difference. And the judgement which is done is registered with the some evident methods and principles.The ilam and huccet of the kadı's, documents which involves registrations that are recorded because of their job are named as "ser'iye trials". These ser'iye trials which illuminate the legal, economic, military, managerial and the social associations in the last 500 years of Ottoman State are not only trial notebooks and it is not true to compare with current ones. Şeriye trials are as the mirror of the that day. Ser'iye trials in the every country center are the strongest and the most reliable source of history. There is no doubt that the şeriye trials are not only first degree source of knowledge for the general Ottoman history but also important for the local histories.Now in our country there are thousands of untouched ser'iye trials.To learn the general history and law history these şeriye trials must be transcribed and analysed in academic level.With this master thesis we analysed one of these books. We observe that the scientific knowledge that we get from this thesis confirms some of our old knowledges and adds some new knowledges to the law association

Development real-time analysis method of frequently used antiepilectic drugs with LC-MS/MS

YÖK Tez No: 588144Bu çalışmada, sık kullanılan antiepileptik ilaç etken maddeleri olan Karbamazepin, Okskarbazepin, Fenitoin, Diazepam, Lorazepam, Klonazepam, Levetirasetam, Gabapentin ve Lamotrigin gibi moleküllerin tayini için, insan kanında Sıvı Kromatografisi-Kütle Spektrometresi (LC-MS/MS) cihazı ile basit, hızlı, kantitatif değer verilebilen ve güvenilir bir metot geliştirilmiştir. Her bir ilaç etken maddesi için geri kazanım, doğruluk, yüzde bağıl standart sapma, gözlenebilme sınırı ve alt tayin sınırı gibi bazı validasyon parametreleri belirlenmiştir. Etken maddelerin her biri için belirlenen konsantrasyonlarda; LOD değerleri için 1 ng.mL-1; 0,05 ng.mL-1-0,16 ng.mL-1, 25 ng.mL-1; 0,12 ng.mL-1-0,46 ng.mL-1, 75 ng.mL-1; 0,20 ng.mL-1-0,68 ng.mL-1 , LOQ değerleri için 1 ng.mL-1; 0,17 ng.mL-1-0,52 ng.mL-1, 25 ng.mL-1; 0,40 ng.mL-1-1,54 ng.mL-1, 75 ng.mL-1 ; 0,67 ng.mL-1-2,26 ng.mL-1 aralığında sonuçlar bulunmuştur. Metot % geri kazanım yönünden 1 ng.mL-1 konsantrasyonunda %98 seviyelerinde, yüksek konsantrasyonlarda ise %99 seviyelerinde tutulmuş ve EURACHEM klavuzuna göre uygun olduğu görülmüştür.In this study, it has been developed simple, rapid, quantitative, and reliable method for active substances of frequently used antiepilectic drugs detection such as carbamazepine, oxcarbazepine, phenytoin, diazepam, lorazepam, clonazepam, levetiracetam, gabapentin and lamotrigine in human blood by using liquid chromatography-mass spectrometry (LC-MS/MS) device. It has been validated in terms of recovery, accuracy, percentage of relative standart deviation, limit of quantification and limit of detection for each active substance of drugs. LOD and LOQ values for obtained concentrations of each active substances were resulted that 1 ng.mL-1; 0,05 ng.mL-1-0,16 ng.mL-1, 25 ng.mL-1; 0,12 ng.mL-1-0,46 ng.mL-1, 75 ng.mL-1; 0,20 ng.mL-1-0,68 ng.mL-1 and 1 ng.mL-1; 0,17 ng.mL-1-0,52 ng.mL-1, 25 ng.mL-1; 0,40 ng.mL-1-1,54 ng.mL-1, 75 ng.mL-1 ; 0,67 ng.mL-1-2,26 ng.mL-1 respectively. This method was resulted in %98 recovery at 1 ng.mL-1 concentration and %99 recovery at higher concentration levels and also confirmed to EURACHEM guide

Increasing ship operational reliability through the implementation of a holistic maintenance management strategy

Ship maintenance was initially considered as more of a financial burden than as a way to preserve safety, environment and quality transportation. The benefits from applying a sound and systematic maintenance policy are emerging both in the minimisation of unnecessary downtime as well as in the increase of operational capability. In this paper, a novel predictive maintenance strategy is demonstrated, combining the existing ship operational and maintenance tasks with the advances stemming from new applied techniques. The initial step for the application of the above-mentioned strategy is also shown regarding the machinery space of a cruise ship. Well-known tools are applied such as Failure Modes, Effects and Criticality Analysis (FMECA) and Fault Tree Analysis (FTA). Outcomes of this study are the identification of the critical components of the system, the estimation of the reliability of the overall system and sub-systems, the prioritisation of the maintenance tasks and finally the availability of the specific end events/items

Investigation of PhiKZ phage therapy against Pseudomonas aeruginosa in mouse pneumonia model

Background/aim: The aim of this study was to investigate the effects of PhiKZ phage therapy and meropenem alone or combined treatments in a pneumonia mouse model induced by the Pseudomonas aeruginosa PAO1 strain. The cross- talk between lungs and kidneys was also determined