Nano-perlite as an alternative reinforcing filler to silica in PDMS composites

Perlite is a highly potential national resource, and its use in silicone elastomer compounds as an alternative reinforcing filler to commercial grade fumed silica is targeted in this thesis work. Thus, comparative results are projected to be acquired. Expanded and raw perlite are characterized using X-Ray Diffraction (XRD), BET Surface Area Analyzer, Pycnometer and Scanning Electron Microscopy (SEM). Attrition mill is used to reduce particle size of expanded perlite. Dynamic Light Scattering (DLS) results showed that particle size was around 260 nm, whereas Scanning Electron Microscopy revealed particle size was between 40-50 nm. Using BET surface analysis and surface titration experiments, hydroxyl group density on expanded perlite surface was calculated, which came out to be 0.0406 –OH/nm2. Perlite and PDMS masterbatches were prepared using a high-speed mixer and mechanical and rheological properties of the elastomers cured from the masterbatches were studied using a Universal Testing Machine (UTM) and Rubber Process Analyzer (RPA 2000). Surface of the mineral was further modified using Hexamethyldisilazane, increasing wettability and mechanical properties of the elastomer samples. Rheological studies and SEM characterization showed a homogeneous distribution of the filler. As a result, surface modified nano expanded perlite exhibited uniform dispersity in the PDMS matrix, similar to commercial grade fumed silica, and their composites exhibited good mechanical properties

The predictor role of irrational beliefs and social appearance anxiety on emotional eating

Bu araştırmanın amacı geç ergenlik dönemindeki bireylerin irrasyonel inanışlarının vesosyal görünüş kaygılarının duygusal yeme davranışları üzerindeki yordayıcı rolünüincelemektir. Araştırma örneklemi 18-24 yaş aralığındaki 297 katılımcıdanoluşmaktadır. Katılımcılardan elde edilen veriler, Sosyo-Demografik Bilgi Formu,Genel Tutum ve İnanışlar Ölçeği (Kısa Formu), Sosyal Görünüş Kaygısı Ölçeği veDuygusal Yeme Ölçeği aracığıyla toplanmıştır. Yapılan istatiksel analizler sonucunda,irrasyonel inanışlar ve sosyal görünüş kaygısı puanlarının, duygusal yeme düzeyinianlamlı ve pozitif yönde yordadığı bulunmuştur. Sonuç olarak, bulgular geç ergenlerinduygusal yeme davranışları üzerinde sosyal görünüş kaygısının ve irrasyonel inanışlarınönemli değişkenler olduğunu göstermektedir. Araştırma sonuçlarının, irrasyonelinanışlar, sosyal görünüş kaygısı ve duygusal yeme arasındaki ilişkiye ışık tutarakliteratüre katkı sağlayacağı düşünülmektedir.The purpose of this study is to examine the predictive role of irrational beliefs andsocial appearance anxiety on emotional eating behaviors of late adolescents. Theresearch sample consists of 297 participants aged 18-24. The Socio-DemographicInformation Form, the General Attitudes and Beliefs Scale (Short Form), the SocialAppearance Anxiety Scale, and the Emotional Eating Scale were used to collect data.As a result of the statistical analysis, it was found that irrational beliefs and socialappearance anxiety scores significantly and positively predicted emotional eating level.In conclusion, the findings indicate that social appearance anxiety and irrational beliefsimportant variables on emotional eating behaviors of late adolescents. It is consideredthat the results of the research will contribute to the literature by shedding light on therelationship between irrational beliefs, social appearance anxiety and emotional eating.Publisher's Versio

The role of expressing feelings in the relationship between dissociative findings and rumination in late adolescence

Bu araştırmanın temel amacı son ergenlik dönemindeki bireylerin dissosiyatif bulguları ile ruminasyon düzeyleri arasındaki ilişkide duyguları ifade etmenin aracı rolünü̈ incelemektir. Araştırmaya 18-24 yasları arasında olan 502 kişi katılmıştır. Veriler, Sosyodemografik Bilgi Formu, Dissosiyasyon Ölçeği (DIS-Q), Ruminatif Düşünce Biçimi Ölçeği (RDBÖ) ve Duyguları İfade Etme Ölçeği (DİEÖ) aracılığıyla toplanmıştır. Araştırmadan elde edilen bulgulara göre son ergenlik dönemindeki bireylerin ruminasyon düzeyleri arttıkça duyguları ifade etme düzeylerinin azaldığı ve dissosiyasyon düzeylerinin arttığı; duyguları ifade etme düzeyleri azaldıkça dissosiyasyon düzeylerinin arttığı görülmüştür. Son ergenlik dönemindeki bireylerin dissosiyatif bulguları ile ruminasyon düzeyleri arasındaki ilişkide duyguları ifade etmenin kısmi aracı etkisi olduğu saptanmıştır. Araştırmamızın söz konusu değişkenlerin geçmiş araştırmalarda sınırlı sayıda incelenmesi açısından literatüre katkı sağladığı düşünülmektedir.The aim of this study is to examine the mediating role of expressing feelings on the relationship between dissociative findings and rumination levels of individuals in the late adolescence period. The study included 502 people between the age of 18-24. The data were collected through the Sociodemographic Information Form, Dissociation Questionnaire (DIS-Q), Ruminative Thought Style Questionnaire and Emotional Expression Questionnaire. According to the findings obtained from the study, as the rumination levels of the individuals in the late adolescent period increased, the level of expressing their feelings decreased and the dissociation levels increased; it was observed that as the expression levels of emotions decreased, the dissociation levels increased. It was found that expressing feelings had a partial mediator effect on the relationship between dissociative findings and rumination levels of individuals in the late adolescent period. It is thought that our study contributed to the literature in terms of examining these variables in a limited number of previous studies.Publisher's Versio

Our Experience with Percutaneous and Surgical Tracheotomy in Intubated Critically Ill Patients

Objective:Open surgical tracheotomy (OST) and percutaneous dilatational tracheotomy (PDT) are commonly used for securing airway in intubated critically ill patients. The purpose of this study was to compare the safety of OST and PDT, particularly in intubated critically ill patients.Methods:The medical records of intubated critically ill patients who underwent tracheotomy between August 2006 and July 2017 were analyzed retrospectively. Minor and major complication rates were compared according to the tracheotomy technique. Preoperative intubation time, postoperative decannulation time, reason for hospitalization, and demographic data, including the Acute Physiology and Chronic Health Evaluation (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores, were evaluated.Results:A total of 332 cases were enrolled into the study. The minor and major complication rates for both techniques were 27.2%, 8.8%, 9.7% and 3.2%, respectively. Minor and major complication rates were higher in the OST group (p=0.01, p=0.03, respectively). The rate of every single complication was also compared on groups’ basis. Accidental decannulation (p=0.02) and pneumothorax (p=0.05) were found to be significantly frequent in the OST group. There was no impact of the preoperative intubation time on the minor (p=0.20) and major complication (p=0.29) rates found. There was no statistically significant difference regarding the postoperative decannulation time (p=0.32). Also, there was no statistically significant difference between two groups in terms of the APACHE II (p=0.69) and SOFA (p=0.37) scores. However, a statistically significant difference between the groups in terms of overall survival was found, in favor of PDT (p<0.001).Conclusion:This study revealed that PDT is safer than OST, particularly in intubated critically ill patients

EVALUATION OF FETAL AND MATERNAL RESULTS IN TWİN PREGNANCIES

Amaç: İkiz gebelikler tüm gebeliklerin %1-2’sini, perinatal mortalitenin ise %10-15’ini oluşturmaktadır. Perinatal mortalite ve morbidite başlıca prematür eylem nedeni ile ortaya çıkmaktadır. Bu çalışmada kliniğimizde doğumu gerçekleşen ikiz gebeliklerin maternal ve fetal sonuçların değerlendirilmesi amaçlanmıştır. Gereç ve Yöntem: Ocak 2012-Mayıs 2014 tarihleri arasında kliniğimizde doğum yapmış 47 ikiz gebelik olgusunun dosya kayıtları incelenerek maternal yaş, doğum sırasında ortalama gebelik haftası, ortalama doğum kilosu, yenidoğan yoğun bakım ihtiyacı olup olmadığı, bebeklerin 1. ve 5. dakika Apgar skorları değerlendirildi. Sonuçlar ortalama ± standart sapma olarak ifade edildi. Bulgular: İkiz gebelik sıklığı %1,6 olarak tespit edildi. Ortalama maternal yaş 30,19 ± 5,59 (aralık: 18-45), ortalama gravida 2,35 ± 1,70, ortalama parite 0,95 ± 1,27, doğum sırasında ortalama gebelik haftası 33,43 ± 6,02 (aralık: 29-39) olarak tespit edildi. Olguların %19,14’de (9 olgu) hipertansiyon mevcuttu. Olguların %14,9’u (7 olgu) ise diyabet ile komplike idi. Yenidoğan doğum kiloları ortalama 2263,97 ± 585,85 gr (aralık: 820-3670 gr), 1.dakika Apgar skorları 8,50 ± 1,80 ve 5.dakika Apgar skorları 8,54 ± 1,25 olarak bulundu. Yenidoğan bebeklerin %20’sinde yenidoğan bakım ihtiyacı oldu; %10 bebekte solunum yolu ile ilgili komplikasyonlar gelişti. Sonuç: İkiz gebelikler halen perinatal ve maternal morbidite nedenidir. Bu gebelikler normal popülasyona göre daha sık diyabet ve hipertansiyon ile komplike olmaktadır. Perinatal sonuçlar özellikle doğum haftası ile ilişkilidir.Objective: Twin pregnancies account for 1-2% of all pregnancies and for 10-15% of perinatal mortality. Perinatal mortality and morbidity occurs mainly due to preterm birth. With this study, we aimed to analyse the fetal and maternal outcomes of twin pregnancies who gave birth in our clinic. Material and Method: The file records of 47 twin pregnancies giving birth in our clinic between January 2012 and May 2014 were analysed and the data about the maternal age, gestational age, mean fetal birth weight, the need of the admission to neonatal intensive care unit, the Apgar scores at 1 and 5th minutes was evaluated. The results were expressed as mean ± standard deviation. Results: The incidence of twinning was 1.6%. Mean maternal age was 30.19 ± 5.59 (range: 18-45), mean gravidity was 2.35 ± 1.70, mean parity was 0.95 ± 1.27, mean gestational week during labor was 33.43 ± 6.02 (range: 29-39). 9 cases (19.14%) were complicated with hypertension and 7 cases (14.9%) were complicated with diabetes. The mean birth weights of newborns were 2263.97 ± 585.85 gr (range: 820-3670 gr); Apgar scores at 1. and 5.minute were 8.50 ± 1.80 and 8.54 ± 1.25 respectively. 20% of newborns needed treatment at the neonatal intensive care unit and 10% of newborns developed complications regarding the respiratory system. Conclusion: Twin pregnancies are still a cause of perinatal and maternal morbidity. These pregnancies are complicated more commonly with diabetes and hypertension, compared with singleton pregnancies. Perinatal outcomes are especially related to the gestational ag

Vicariance and dispersal in southern hemisphere freshwater fish clades: a palaeontological perspective

Widespread fish clades that occur mainly or exclusively in fresh water represent a key target of biogeographical investigation due to limited potential for crossing marine barriers. Timescales for the origin and diversification of these groups are crucial tests of vicariant scenarios in which continental break‐ups shaped modern geographic distributions. Evolutionary chronologies are commonly estimated through node‐based palaeontological calibration of molecular phylogenies, but this approach ignores most of the temporal information encoded in the known fossil record of a given taxon. Here, we review the fossil record of freshwater fish clades with a distribution encompassing disjunct landmasses in the southern hemisphere. Palaeontologically derived temporal and geographic data were used to infer the plausible biogeographic processes that shaped the distribution of these clades. For seven extant clades with a relatively well‐known fossil record, we used the stratigraphic distribution of their fossils to estimate confidence intervals on their times of origin. To do this, we employed a Bayesian framework that considers non‐uniform preservation potential of freshwater fish fossils through time, as well as uncertainty in the absolute age of fossil horizons. We provide the following estimates for the origin times of these clades: Lepidosireniformes [125–95 million years ago (Ma)]; total‐group Osteoglossomorpha (207–167 Ma); Characiformes (120–95 Ma; a younger estimate of 97–75 Ma when controversial Cenomanian fossils are excluded); Galaxiidae (235–21 Ma); Cyprinodontiformes (80–67 Ma); Channidae (79–43 Ma); Percichthyidae (127–69 Ma). These dates are mostly congruent with published molecular timetree estimates, despite the use of semi‐independent data. Our reassessment of the biogeographic history of southern hemisphere freshwater fishes shows that long‐distance dispersals and regional extinctions can confound and erode pre‐existing vicariance‐driven patterns. It is probable that disjunct distributions in many extant groups result from complex biogeographic processes that took place during the Late Cretaceous and Cenozoic. Although long‐distance dispersals likely shaped the distributions of several freshwater fish clades, their exact mechanisms and their impact on broader macroevolutionary and ecological dynamics are still unclear and require further investigation.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/148368/1/brv12473_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/148368/2/brv12473.pd

†Kenyaichthyidae fam. nov and †Kenyaichthys gen. nov - First Record of a Fossil Aplocheiloid Killifish (Teleostei, Cyprinodontiformes)

The extant Cyprinodontiformes (killifishes) with their two suborders Cyprinodontoidei and Aplocheiloidei represent a diverse and well-studied group of fishes. However, their fossil record is comparatively sparse and has so far yielded members of the Cyprinodontoidei only. Here we report on cyprinodontiform fossils from the upper Miocene Lukeino Formation in the Tugen Hills of the Central Rift Valley of Kenya, which represent the first fossil record of an aplocheiloid killifish. A total of 169 specimens - mostly extraordinarily well preserved and a sample of ten extant cyprinodontiform species were studied on the basis of morphometrics, meristics and osteology. A phylogenetic analysis using PAUP was also conducted for the fossils. Both the osteological data and the phylogenetic analysis provide strong evidence for the assignment of the fossils to the Aplocheiloidei, and justify the definition of the new family dagger Kenyaichthyidae, the new genus dagger Kenyaichthys and the new species dagger K. kipkechi sp. nov. The phylogenetic analysis unexpectedly places dagger Kenyaichthys gen. nov. in a sister relationship to the Rivulidae (a purely Neotropical group),a probable explanation might be lack of available synapomorphies for the Rivulidae, Nothobranchiidae and Aplocheilidae. The specimens of dagger K. kipkechi sp. nov. show several polymorphic characters and large overlap in meristic traits, which justifies their interpretation as a species flock in statu nascendi. Patterns of variation in neural and haemal spine dimensions in the caudal vertebrae of dagger Kenyaichthys gen. nov. and the extant species studied indicate that some previously suggested synapomorphies of the Cyprinodontoidei and Aplocheiloidei need to be revised

Exploratory Shopping: Attention Affects In-store Exploration and Unplanned Purchasing

A fundamental function of retailing is to bring products into the view of shoppers, because viewing products can activate forgotten or new needs. Retailers thus employ various strategies to entice shoppers to explore the product assortment and store environment, in the hopes of stimulating unplanned purchasing. This article investigates consumers’ breadth of attention as a mechanism of such in-store exploration and hence of unplanned purchasing. Specifically, attentional breadth is the focus that is directed to a wider or more limited area in processing visual scenes. Across several lab and field experiments, the authors show that shoppers’ attentional breadth activates an exploratory mindset that stimulates visual and physical exploration of shopping environments, ultimately affecting their product choices and unplanned purchasing. The results also show that more impulsive buyers are more susceptible to these effects. The present article thus complements and constrains prior theorizing on mindset theory, attention, store exploration, and unplanned purchasing, all of which are of practical importance to both retailers and consumers

Intrahepatic Cholestasis of Pregnancy: Case Series

Gebeliğin intrahepatik kolestazı, gebeliğin ikinci yarısında vücutta yaygın kaşıntı ile ortaya çıkan bir karaciğer hastalı- ğıdır. Gebeliğe bağlı en sık karaciğer patolojisidir. Patofizyolojisinde gebelikte artan östrojenin safra asitlerinin atılımını engellemesi rol oynar. Yaygın kaşıntı ve artmış serum safra asitleri ile karakterizedir. Maternal komplikasyonları nadirdir. Ancak spontan preterm eylem, mekonyumlu amniotik sıvı ve fetal distres, intrauterin ani fetal ölüm gibi ciddi perinatal komplikasyonlara neden olabilir. Bu nedenle gebe bir olguda yaygın kaşıntı tespit edildiğinde olası komplikasyonlar nedeni ile gebeliğin intrahepatik kolestazı mutlaka akılda tutulmalıdır. Bu çalışmada gebeliğe bağlı sekiz intrahepatik kolestazlı olgunun 10 bebeği (biri üçüz gebelik) perinatal sonuçları ile incelenerek güncel literatürler ışığında hastalığın etiyolojisi ve yönetiminin gözden geçirilmesi amaçlandı.Intrahepatic cholestasis of pregnancy (ICP) is a liver disease that manifests as common pruritus during the second half of pregnancy. ICP is the most common liver disease triggered by pregnancy. Increasing levels of estrogen play a key role in the pathophysiology of the disease by limiting the passage of serum bile acids. ICP is characterized by increased serum bile acids and pruritus. Maternal complications are rare. However, ICP may cause severe perinatal complications such as spontaneous preterm labor, meconium staining of the amniotic fluid, fetal distress and sudden in utero fetal death. Due to serious adverse outcomes, the possibility of ICP should be examined in pregnant women with puritus. In the present study, we present 10 cases with ICP and briefly review the current literature regarding the etiology and clinical management of this condition