74 research outputs found
A Practice Relating to Var Method on Determining Financial Market Risks
DergiPark: 326708trakyasobedAs long as financial markets exist risk component is also going to exist in thesystem. What is important for firms and investors acting in financial markets isforeseeing the probable risks and to act in new positions in parallel with theseforesights, besides minimizing the risks. In this paper, recently –relating to riskmanagement- most preferred VaR value analysis methods have been examined, andVaRs have been measured in hypotetical portfolios developed by variance –covariance method.Since it has become into effect, pension mutual funds in private pensionsystem developing and emerging in Turkey are one of the factors that transmit longterm investments to capital markets.In economical researchs, it is found that revenue backed public borrowingtools correspond to low-risk funds of pension mutual funds. The results achievedfrom the calculations made in this paper are in parallel with those economicinterpretationsFinansal piyasalar var olduğu sürece risk unsuru sistem içerisinde varlığını sürdürecektir. Finansal piyasalarda faaliyet gösteren şirketler ve yatırımcılar için önemli olan, risklerin en aza indirilmesinin yanında karşılaşılabilecek riskleri tahmin etmek ve bu tahminler ışığında pozisyon alabilmektir. Bu çalışmada, günümüzde risk yönetimine ilişkin yaygın olarak tercih edilen riske maruz değer analizi yöntemleri incelenmiş ve bu yöntemlerden birisi olan varyans – kovaryans yöntemi ile oluşturulan hipotetik portföylerde riske maruz değer (Value at Risk –VaR) ölçümleri yapılmıştır. Türkiye’de faaliyete geçtiği günden beri gelişerek büyüyen bireysel emeklilik sistemi dahilindeki bireysel emeklilik yatırım fonları, ülke ekonomisini güçlendiren ve sermaye piyasalarına uzun vadeli kaynak aktaran en önemli faktörlerden biridir.Bu nedenle çalışmada portföyler 2008, 2009 ve 2010 yıllarında Türkiye’de faaliyet gösteren gelir amaçlı kamu borçlanma araçları emeklilik yatırım fonlarından oluşturulmuştur. Yapılan iktisadi çalışmalarda, gelir amaçlı kamu borçlanma araçları emeklilik yatırım fonlarının, riski düşük fonlar grubuna girdiği bulgulanmıştır. Çalışmada yapılan hesaplamalar sonucunda bu iktisadi yorumlara paralel sonuçlar çıkmıştır
Ülkelerin Ekonomik Göstergelerinin Avrupa Birliğine Üye Olmadaki Etkisinin İstatistiksel Tekniklerle Belirlenmesi
DergiPark: 326418trakyasobedAs known the accordance process between Turkey and European Union is continuing for along time. It’s aimed by this study to consider presence of the differences about basic economical criterions between member countries and our country. Shortly the purpose of this study is to determine the economical indicators which are the most important about to be a member of European Union. 21 variables and 208 country data are used in this study. The data are got by World Bank’s The World Development Indicators 2007 program. The multivariate statistical techniques which exploited in this study are factor analysis and logistic regression analysis. In accordance with the result of holded analysis it is determined that the most effective economical variables to be a member that are exports of goods and services, GNI per capita PPP, Gross national expenditure, export, import, ppp conversion factor to official exchange rate ratio and claims on governments, etc. (annual growth as % of M2). According to the findings; it could be suggested that the primary goal is to restore the condition of said 7 economical indicators.Bilindiği gibi Avrupa Birliği (AB) ile Türkiye arasında uyum süreci uzun süredir devam etmektedir. Bu çalışmayla; AB’ye üye ülkelerle Türkiye arasında bazı temel ekonomik ölçütler açısından farklılıkların olup olmadığını irdelenmek amaçlanmıştır. Kısaca araştırmanın amacı; Avrupa Birliği’ne üye olma konusunda en belirleyici ekonomik göstergelerin belirlenmesidir. Çalışmada 21 adet değişken ve 208 ülke verisi kullanılmıştır. Veriler dünya bankasının World Development Indicators 2007 programından elde edilmiştir. Çalışmada çok değişkenli istatistiksel tekniklerden Faktör ve Lojistik Regresyon analizinden yararlanılmıştır. Yapılan analizler sonucunda; Avrupa Birliği’ne üye olmada en etkili ekonomik değişkenlerin; mal ve hizmet ihracatı, satınalma gücü paritesi- Kişi başına milli gelir, gayrisafi harcama, ihracat, ithalat, satınalma gücü paritesini döviz kuruna dönüştürme oranı ve hükümetin para arzındaki yıllık büyüme hedefi olduğu saptanmıştır. Bulgular ışığında; Türkiye’nin öncelikli hedef olarak bu adı geçen 7 ekonomik göstergenin durumunu iyileştirmesi önerilebilir
Hemophagocytic syndrome due to leishmania infection diagnosed with immunofluorescence antibody test
Leishmaniasis is a reticuloendothelial system disease that mostly observed before the age of 5. Visceral infection causes long-standing fever, weight loss, weakness, pancytopenia, and hepatosplenomegaly. Leishmania infantum is responsible for visceral leishmaniasis (VL) in Turkey. We present a case of hemophagocytic syndrome due to Leishmania infection diagnosed with an immunofluorescence antibody test (IFAT). Leishmania amastigotes were not observed on bone marrow aspiration. We consider that IFAT is very important for parasite detection in the diagnosis of VL in children, particularly when amastigotes are not obtained on bone marrow aspiration
Mycorrhizal fungi diversity of Serapias orientalis
Orkideler, yumrularının aşırı toplanması ve habitatlarının ciddi şekilde tahrip olması sonucu yok olma
tehdidi altındadır. Doğada orkidelerin korunması mikorizal fungus biyolojik çeşitliliğinin varlığına
bağlıdır. Bu çalışmada, Orta ve Doğu Karadeniz bölgesinde 4 ilin (Samsun, Ordu, Giresun, Trabzon)
sınırları içinde farklı habitatlardan toplanan Serapias orieantalis (Greuter ) Bauman H, Künkele
köklerindeki mikorizal fungusların moleküler tanımlaması yapılmıştır. Bitki kökleri 2015 bahar
aylarında toplanmış ve önce mikroskopta incelenerek mikorizal funguslar izole edilmiştir. Saflaştırılan
izolatlar, koloni özellikleri (koloni tipi, koloni rengi), hif yapısı (hif çapı ve dallanma yapısı) ve çekirdek
sayılarının belirlenmesi amacıyla PDA (patates dektroz agar) ortamında geliştirilmiştir. İzolatları
morfolojik özelliklerine göre gruplandırmak için küme analizi (UPGMA) yöntemi uygulanmış ve
kladogram oluşturulmuştur. Kümeleme analizine göre oluşturulan 3 grubun izolatlarını moleküler
düzeyde tanımlayabilmek için ITS-1 ve ITS-4 primerleri kullanılarak nüklear ribozomal DNA (rDNA)’nın
ITS1-5.8S-ITS2 gen bölgesi çoğaltılmıştır. DNA dizilimine dayanarak, 13 Rhizoctonia benzeri izolatın
Tulasnella cinsi ile 2 Rhizoctonia benzeri olmayan izolatın Fusarium oxysporum Schltdl. türü ile yakın
ilişkili olduğu bulunmuştur.Orchids are under a serious threat of extinction as a result of both excessive collecting and severe
destruction of their habitats. Studies conducted have shown that the protection of orchids depends on
the presence of mycorrhizal fungal biodiversity. In this study, molecular identification of mychorrhizal
fungi of Serapias orieantalis roots taken from different habitats within the borders of 4 provinces
(Samsun, Ordu, Giresun, Trabzon) in the Central and Eastern Black Sea region was conducted. Plant
roots were collected in the spring of 2015 and first examined under a microscope and then mycorrhizal
fungi were isolated. Purified isolates were developed in PDA (potato dectrose agar) medium in order
to determine colony characteristics (colony type, colony color), hif structure (hif diameter and
branching structure) and core numbers. Cluster analysis (UPGMA) method was applied to group the
isolates according to their morphological characteristics and a cladogram was created. Nuclear
ribozomal DNA (rDNA)’nın ITS 1-5.8S-ITS 2 gene region was amplified using ITS 1/ITS 4 primers in order
to identify isolates of 3 groups formed according to morphological data at the molecular level. Based
on the DNA sequence, 13 Rhizoctonia-like isolates were closely related to the Tulasnella genus, and 2
Rhizoctonia-unlike isolates were closely related to the Fusarium oxysporum
A High Throughput Lab-On-A-Chip System for Label Free Quantification of Breast Cancer Cells under Continuous Flow
This paper presents an LOC system combining microfluidic DEP channel with a CMOS image sensor for label and lens free detection and real-time counting of MCF-7 cells under continuous flow. Trapped and then released MCF-7 cells are accurately detected and counted under flow with a CMOS image sensor integrated underneath the DEP channel, for the first time in the literature. CMOS image sensor can capture 391 frames per second (fps) that allows detection of the released cells flowing through the channel with a flow rate up to 130 mu l/min (0.468 m/s). Therefore, the proposed system is able to detect the cells under high flow where conventional techniques for cell quantification such as fluorescent tagging become unusable. Detected cells are automatically counted with a computer program and the counting accuracy of the whole system is 95%. (C) 2016 The Authors. Published by Elsevier Ltd
BRAF V600E mutation in papillary thyroid cancer is correlated with adverse clinicopathological features but not with iodine exposure
Introduction: BRAFV600E activating mutation is the most frequent genetic abnormality in the pathogenesis of papillary thyroid carcinoma. We aimed to evaluate the association between BRAFV600E mutation and well-established prognostic clinicopathological characteristics as well as iodine exposure.
Material and methods: From 2000 to 2012, the data of PTC patients admitted to Dr. Lutfi Kirdar Kartal Education and Research Hospital in Turkey were reviewed retrospectively. Clinicopathological parameters were collected. BRAFV600E mutation was analysed by DNA sequencing method in tumour specimens. We hypothesised that BRAFV600E mutation prevalence is positively correlated with prolonged iodine exposure and expected to be higher in the second half of the recruitment period due to the increment in time spent from the iodisation process of the table salt in our country. Thus, iodine exposure was categorised as short-term (2000–2006) and long-term (2006–2012).
Results: A total of 197 patients were accrued. The study population predominantly consisted of conventional variant. A statistically significant relationship was observed between BRAFV600E mutation presence and age (p = 0.03), conventional variant PTC (p = 0.00002), T4 stage (p = 0.002), vascular invasion (p = 0.036), thyroid capsule invasion (p < 0.00001), extrathyroidal tissue invasion (p < 0.00001), and lymph node metastasis (p < 0.00001). When categorised as long-term and short-term, iodine exposure was not statistically significantly related with BRAFV600E mutation; however, there were far more PTC cases in the long-term group (86.3% vs. 13.7%).
Conclusion: We revealed that BRAFV600E mutation is associated with adverse clinicopathological parameters. There appeared to be no relation between long-term iodine exposure and BRAFV600E.
Real-world efficacy and safety of Ledipasvir plus Sofosbuvir and Ombitasvir/Paritaprevir/Ritonavir +/- Dasabuvir combination therapies for chronic hepatitis C: A Turkish experience
Background/Aims: This study aimed to evaluate the real-life efficacy and tolerability of direct-acting antiviral treatments for patients with chronic hepatitis C (CHC) with/without cirrhosis in the Turkish population.Material and Methods: A total of 4,352 patients with CHC from 36 different institutions in Turkey were enrolled. They received ledipasvir (LDV) and sofosbuvir (SOF)+/- ribavirin (RBV) ombitasvir/paritaprevir/ritonavir +/- dasabuvir (PrOD)+/- RBV for 12 or 24 weeks. Sustained virologic response (SVR) rates, factors affecting SVR, safety profile, and hepatocellular cancer (HCC) occurrence were analyzed.Results: SVR12 was achieved in 92.8% of the patients (4,040/4,352) according to intention-to-treat and in 98.3% of the patients (4,040/4,108) according to per-protocol analysis. The SVR12 rates were similar between the treatment regimens (97.2%-100%) and genotypes (95.6%-100%). Patients achieving SVR showed a significant decrease in the mean serum alanine transaminase (ALT) levels (50.90 +/- 54.60 U/L to 17.00 +/- 14.50 U/L) and model for end-stage liver disease (MELD) scores (7.51 +/- 4.54 to 7.32 +/- 3.40) (p<0.05). Of the patients, 2 were diagnosed with HCC during the treatment and 14 were diagnosed with HCC 37.0 +/- 16.0 weeks post-treatment. Higher initial MELD score (odds ratio [OR]: 1.92, 95% confidence interval [CI]: 1.22-2.38; p=0.023]), higher hepatitis C virus (HCV) RNA levels (OR: 1.44, 95% CI: 1.31-2.28; p=0.038), and higher serum ALT levels (OR: 1.38, 95% CI: 1.21-1.83; p=0.042) were associated with poor SVR12. The most common adverse events were fatigue (12.6%), pruritis (7.3%), increased serum ALT (4.7%) and bilirubin (3.8%) levels, and anemia (3.1%).Conclusion: LDV/SOF or PrOD +/- RBV were effective and tolerable treatments for patients with CHC and with or without advanced liver disease before and after liver transplantation. Although HCV eradication improves the liver function, there is a risk of developing HCC.Turkish Association for the Study of The Liver (TASL
Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey
Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020
Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries
Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely
Evaluatıon Of The Mechanıcal And Physıcal Propertıes Of A New Resın Based Fıssure Sealant
Günümüzde yaygın olarak kullanılan fissür örtücülerin geliştirilmesi için çalışmalar devam etmektedir. Çürüğün önlenmesinde etkili olan fluoridin fissür örtücülere ilave edilmesiyle fluoridli fissür örtücüler elde edilmiş ve başarıları kanıtlanmıştır. Son zamanlarda içerisindeki S-PRG (Surface pre-reacted glass ionomer) doldurucular sayesinde yüksek miktarda fluorid salma ve reşarj olma kapasitesine sahip olduğu iddia edilen BeautiSealant fissür örtücü kullanılmaya başlanmıştır. Bu çalışmada fluorid içermeyen (Helioseal), fluorid içeren (Helioseal-F) ve S-PRG doldurucu içeren (BeautiSealant) rezin esaslı fissür örtücülerin makaslama bağlanma dayanımı, mikrosızıntı ve demineralizasyonu engelleme özelliklerinin değerlendirilmesi amaçlanmıştır. Makaslama bağlanma dayanımı testi için toplanan dişlerin bukkal yüzeylerine fissür örtücüler uygulanıp ölçümler yapılmıştır. Mikrosızıntı testi için dişler fissür örtücü uygulamasından sonra 24 saat % 0,5 lik bazik fuksin solüsyonunda bekletilip kesit alınarak mikroskop altında incelenmiştir. Fissür örtücülerin demineralizasyonu engelleme özelliğinin değerlendirilmesi için ise, dişlerin bukkal yüzeylerine fissür örtücü uygulaması yapılıp 14 gün pH siklusuna tabi tutulmuştur. Ardından bukko-lingual yönde kesit alınarak, farklı derinliklerde kesitsel mikrosertlik değerleri ölçülmüştür. Yapılan istatistiksel değerlendirme sonuçlarına göre, S-PRG doldurucu içeren BeautiSealant fissür örtücü uygulanan dişlerde makaslama bağlanma kuvveti diğer gruplara göre en yüksek değeri göstermiştir (p<0,001). Mikrosızıntı skorları açısından gruplar arasında istatistiksel olarak anlamlı bir fark bulunamamıştır (p=0,413). Kesitsel mikrosertlik ölçümlerinde ise BeautiSealant ın bazı derinliklerde diğer fissür örtücülere göre istatistiksel olarak anlamlı düzeyde daha yüksek değerler verdiği tespit edilmiştir (p<0,001).Studies have been carried out on improving fissure sealants which are being used more and more widely everyday. Following the inclusion of carries preventive fluoride within fissure sealents, fluoride fissure sealents have been obtained and proven to be highly useful. BeautiSealant, a resin based fissure sealant, was recently introduced claiming to have high recharge capacity and high fluorid release capacity for containing S-PRG fillers. In this study it was aimed to evaluate shear bond strength, micro leakage and inhibition of demineralisation properties of non-fluoride (Helioseal), fluoride (Helioseal-F) and S-PRG filler containing (BeautiSealant) resin-based pit and fissure selants. Fissure sealants were applied to the buccal surfaces of the collected teeth for shear bond strength measurements. For microleakage test, after fissure sealent application, teeth were immersed in %0.5 basic fuchsin solution and later sectioned and examined under microscope. For the demineralization inhibiton property evaluation, fissure sealers were applied to the buccal surfaces of the teeth and waited for 14 days for pH cycling. Afterwards sections were taken in buccolingual direction and crossectional micro hardness tests were done in different depths. According to the statistical evaluation results, shear bond strength of the teeth which were used BeautiSealant was the highest among all (p<0,001). No meaningful difference were found between the results in terms of microleakage properties (p=0,413). Finally BeautiSealant fissure sealant showed higher values statistically for several depths on the crossectional micro hardness tests (p<0,001)
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