Experimental and Theoretical Investigations of Mouldability for Feedstocks Used in Powder Injection Moulding

Experimental and theoretical analyses of mouldability for feedstocks used in powder injection moulding are performed. This study covers two main analyses. (i) The experimental analysis: the barrel temperature, injection pressure, and flow rate are factors for powder injection moulding (PIM). Powder-binder mixture used as feedstock in PIM requires a little more attention and sensitivity. Obtaining the balance among pressure, temperature, and especially flow rate is the most important aspect of undesirable conclusions such as powder-binder separation, sink marks, and cracks in moulded party structure. In this study, available feedstocks used in PIM were injected in three different cavities which consist of zigzag form, constant cross-section, and stair form (in five different thicknesses) and their mouldability is measured. Because of the difference between material and binder, measured lengths were different. These were measured as 533 mm, 268 mm, 211 mm, and 150 mm in advanced materials trade marks Fe–2Ni, BASF firm Catamould A0-F, FN02, and 316L stainless steel, respectively. (ii) The theoretical analysis: the use of artificial neural network (ANN) has been proposed to determine the mouldability for feedstocks used in powder injection moulding using results of experimental analysis. The back-propagation learning algorithm with two different variants and logistic sigmoid transfer function were used in the network. In order to train the neural network, limited experimental measurements were used as training and test data. The best fitting training data set was obtained with three and four neurons in the hidden layer, which made it possible to predict yield length with accuracy at least as good as that of the experimental error, over the whole experimental range. After training, it was found that the R2 values are 0.999463, 0.999445, 0.999574, and 0.999593 for Fe–2Ni, BASF firm Catamould A0-F, FN02, and 316L stainless steel, respectively. Similarly, these values for testing data are 0.999129, 0.999666, 0.998612, and 0.997512, respectively. As seen from the results of mathematical modeling, the calculated yield lengths are obviously within acceptable uncertainties

Can thiamine pyrophosphate prevent desflurane induced hepatotoxicity in rats?

Cetin, Nihal/0000-0003-3233-8009; Arslan, Aynur/0000-0001-5968-5823; yilmaz, adnan/0000-0003-4842-1173WOS: 000374189100004PubMed: 27050787PURPOSE: To investigate the effects of thiamine pyrophosphate (TPP) against desflurane induced hepatotoxicity. METHODS: Thirty experimental animals were divided into groups as healthy (HG), desflurane control (DCG), TPP and desflurane group (TDG). 20 mg/kg TPP was injected to intraperitoneally TDG. After one hour of TPP administration, desflurane was applied for two hours. After 24 hours, liver tissues of the animals killed with decapitation were removed. the oxidant/antioxidant levels and ALT, AST and LDH activities were measured. the histopathological examinations were performed in the liver tissues for all rats. RESULTS: Notwithstanding the levels of oxidants and liver enzymes were significantly increased (p<0.0001), antioxidant levels were significantly decreased in DCG (p<0.0001). on contrary to the antioxidant parameters were increased (p<0.05) the oxidant parameters and liver enzymes were decreased in TDG (p<0.0001). Whereas multiple prominent, congestion, hemorrhage and dilatation were observed in sinusoids and lymphocyte-rich inflammation results in the centrilobular and portal areas of liver tissue in DCG, these findings were observed less frequently in TDG. CONCLUSION: Thiamine pyrophosphate prevented liver oxidative damage induced with desflurane and may be useful in prophylaxis of desflurane induced hepatotoxicity.Erzincan University Scientific Research Projects DepartmentErzincan Binali Yildirim University [SAG-B-080715-0173]Erzincan University Scientific Research Projects Department (Project no SAG-B-080715-0173

Does the Change in the Indications of Endoscopic Sinonasal Surgery Continue? Data between 1994-2018

Objective: Endoscopic sinonasal surgery (ESS) has changing over the years in parallel with the developments in endoscopy devices, video-imaging techniques, and surgical instruments. In the present study we investigated whether the indications of patients who underwent surgery over a period of 25 years have accommodated to these changes.Methods: We retrospectively evaluated 1173 patients who underwent surgery in our clinic from 1994 through 2007, and 954 patients who underwent surgery from 2008 through 2018. The patients were divided into three groups as follows: chronic rhinosinusitis with polyps (CRSwNP), chronic rhinosinusitis without polyps (CRSsNP), and others. The changes in the indications during the first 14 years and the following 11 years were compared, and the results were statistically evaluated.Results: A significant decrease was observed in the number of patients who underwent surgery following the diagnosis of CRSsNP (p<0.001). In addition, a statistically significant increase was found in CRSwNP (p<0.001) and other (p<0.001) indications.Conclusion: When ESS indications identified in our clinic were reviewed, it was observed that the increasing trend in CRSwNP rate in the first 14 years continued, there was a significant increase in non-CRS indications in the last 11 years, and there has been an increase in patients with fungal sinusitis, especially in this group

KEY TRENDS IN EARLY FILM STUDIES: EXAMPLE OF PAYNE FUND STUDIES

19. yüzyılın sonlarında bir sanat ve eğlence aracı olarak toplumsal yaşama dâhil olan sinema kısa bir süre içerisinde kitlesel bir boyut kazandı. Söz konusu dönemde orta ve alt sınıfların en çok tercih ettikleri eğlence aracı olan sinema aynı zamanda bazı toplumsal kesimlerde kaygı ve endişelere de neden oluyordu. Özellikle muhafazakâr toplumsal kesimler, sinema filmlerinde suç, şiddet, cinsellik, alkol ve sigara tüketiminin özendirici bir biçimde temsil edildiğini iddia ediyorlardı. Bu kaygılar derinleştikçe ve yaygınlaştıkça kamu ve sivil kuruluşlar bu konuda bazı adımlar atmak zorunda kaldılar. Amerika Birleşik Devletleri’nde 1929-1932 yılları arasında Sinema Filmlerini Araştırma Konseyi ile Payne Araştırma ve Deney Fonu işbirliği ile sinemanın çocukların ve gençlerin davranışları üzerindeki etkilerine odaklanan Sinema ve Gençlik: Payne Fonu Çalışmaları isimli bir araştırma serisi gerçekleştirildi. Bu araştırma serisinin sonuçları on iki rapor olarak yayınlandı. Araştırmanın sonuçlarına göre sinema, çocukların ve gençlerin tutum ve davranışlarının oluşmasında önemli bir araca dönüşmüştür ve sinema çocuklarda davranış bozukluklarına ve uyku problemlerine neden olmaktadır. Araştırmanın raporları yayınlandıktan sonra Amerika Birleşik Devletleri’nde sinema ile ilgili ağır sansür politikaları uygulamaya konmuştur. Sinema araştırmaları tarihinin en kapsamalı ve en etkili çalışmalarından biri olan bu seri bir sonraki dönemlerde yapılan bir çok araştırmaya da ilham kaynağı olmuştur. Payne Fonu Çalışmaları’na paradigma, yöntem, içerik ve sonuçlar çerçevesinde odaklanan çalışmamız literatür taramasına dayanan ve betimsel bir çalışmadır ve Payne Fonu Çalışmaları’nın görünürlüğünü arttırarak sinema sosyolojine katkı sunmayı amaçlamaktadır.Cinema, which was included in social life as an art and entertainment tool at the end of the 19th century, gained a mass dimension in a short time. Cinema, which was the most preferred entertainment tool for the middle and lower classes in that period, also caused anxiety and worries in some social segments. Especially conservative social groups claimed that crime, violence, sexuality, alcohol and cigarette consumption were represented in an encouraging way in movies. As these concerns deepened and became widespread, public and non-governmental organizations had to take some steps in this regard. In the United States, between 1929 and 1932, a research series called Motion Pictures and Youth: The Payne Fund Studies was conducted in cooperation with the Motion Picture Research Council and the Payne Research and Experiment Fund, focusing on the effects of cinema on the behavior of children and youth. The results of this research series have been published in twelve reports. According to the results of the research, cinema has turned into an important tool in the formation of attitudes and behaviors of children and young people, and cinema causes behavioral disorders and sleep problems in children. After the reports of the research were published, heavy censorship policies were implemented in the United States of America. This series, which is one of the most comprehensive and influential studies in the history of film studies, has also inspired many researches in the following periods. Our study, which focuses on Payne Fund Studies within the framework of paradigm, method, content and results, is a descriptive study based on literature review and aims to contribute to the sociology of cinema by increasing the visibility of Payne Fund Studies

In silico studies on stilbenolignan analogues as SARS-CoV-2 Mpro inhibitors

2-s2.0-85103277923COVID-19, a new strain of coronavirus family, was identified at the end of 2019 in China. The COVID-19 virus spread rapidly all over the world. Scientists strive to find virus-specific antivirals for the treatment of COVID-19. The present study reports a molecular docking study of the stilbenolignans and SARS-CoV-2 main protease (SARS-CoV-2 Mpro) inhibitors. The detailed interactions between the stilbenolignan analogues and SARS-CoV-2 Mpro inhibitors were determined as hydrophobic bonds, hydrogen bonds and electronic bonds, inhibition activity, ligand efficiency, bonding type and distance and etc. The binding energies of the stilbenolignan analogues were obtained from the molecular docking of SARS-CoV-2 Mpro. Lehmbachol D, Maackolin, Gnetucleistol, Gnetifolin F, Gnetofuran A and Aiphanol were found to be ?7.7, ?8.2, ?7.3, ?8.5, ?8.0 and ?7.3 kcal/mol, respectively. Osirus, Molinspiration and SwissADME chemoinformatic tools were used to examine ADMET properties, pharmacokinetic parameters and toxicological characteristics of the stilbenolignan analogues. All analogues obey the Lipinski's rule of five. Furthermore, stilbenolignan analogues were studied to predict their binding affinities against SARS-CoV-2 Mpro using molecular modeling and simulation techniques, and the binding free energy calculations of all complexes were calculated using the molecular mechanics/Poisson–Boltzmann surface area (MM-PBSA) method. With the data presented here it has been observed that these analogues may be a good candidate for SARS-CoV-2 Mpro in vivo studies, so more research can be done on stilbenolignan analogues. © 2021 Elsevier B.V

BİR KAVRAMIN KISA TARİHİ: 'MAHALLE BASKISI'

“Mahalle baskısı”, 2007 Mayısından beri Türkiye’de yoğun olarak tartışılan bir kavramdır. Türk toplumu üzerine kafa yoran her bilim adamı ya da sıradan insan söz konusu kavramla bir şekilde karşılaşmıştır. Bu denli yoğun ilgi yaratmasına rağmen sosyal bilimciler arasında mahalle baskısı kavramının ne olduğu konusunda ortak bir anlayış doğmamıştır. Kavram, gündelik siyasi polemiklerin etki alanının dışına çıkamamış ve ideolojik yaklaşımlardan bağımsız bilimsel bir form kazanamamıştır. Bu çalışmada, Şerif Mardin’in mahalle baskısı konusundaki görüşleri farklı bakış açıları da göz önünde bulundurularak tartışılmıştı

KADINA YÖNELİK ŞİDDETİN KAYNAĞINA DAİR LACANYEN BİR DEĞERLENDİRME

Kadına yönelik şiddet probleminin Jacques Lacan’ın kavramları üzerinden tartışıldığı bu çalışma, literatür taramasına dayanan betimsel bir çalışmadır. Sınıfsal konumları ne olursa olsun, kadınların büyük bir çoğunluğu yaşamlarının herhangi bir döneminde fiziksel, cinsel, ekonomik, psikolojik vb. şiddet türlerinden birine maruz kalmaktadırlar. Kadına yönelik şiddetin önüne geçmek için yapılan yasal düzenlemeler, bu anlamda ağırlaştırılan cezai yaptırımlara rağmen bu problem artarak devam etmektedir. Çünkü kadına yönelik şiddetin ortaya çıkmasına ve yeniden üretilmesine neden olan dinamikler sadece hukuksal değil aynı zamanda toplumsaldır. Bu bağlamda kadına yönelik şiddeti besleyen kültürel, toplumsal, siyasi bir arka plan vardır. Dolayısıyla kadına yönelik şiddetin önüne geçmek için şiddetin toplumsal kaynaklarını ifşa etmek gerekmektedir. Lacan’ın simgesel yapı, öteki, arzu, hadım edilme (kastrasyon) gibi kavramları bu tartışma açısından verimli bir zemin sağlamaktadır

Chiral catalysts utilized in the nucleophilic addition of dialkyl-zinc reagents to carbonyl compounds

WOS:000561219600001The aim of this review is an overview of diverse dialkyl zinc pro-chiral aldehydes addition reactions. One way of conducting asymmetric reactions is through the use of chiral catalyst. Therefore, new chiral ligands have attracted considerable attention in organic chemistry. Carbon-carbon bond formation reactions are an active research topic. The addition of dialkyl zinc to pro-chiral aldehydes is one of these popular reactions. Also, the chiral amino alcohols are important substrates for drug synthesis. These chiral ligands can be prepared by a simple synthetic way from easily accessible starting materials. This article reviews current catalyst reactions with the addition of dialkyl zinc to carbonyl compounds.BIDEB-TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)The author is grateful to BIDEB-TUBITAK for providing the postdoctoral scholarship for providing facilities to the Bunch research group at Copenhagen University and also for granting the necessary permissions to the University of Mus Alparslan management

Pirazol Türevlerinin Sentez Metodları

msufbdBu derlemede pirazollerin sentez süreçlerini incelemek hedeflenmiştir. Heterosiklik bileşiklerin önemli bir sınıfını oluşturan pirazoller biyoaktif özelliklerinden dolayı geniş bir çalışma alanı olarak önemi artarak devam etmektedir. Pirazoller biyolojik aktif çeşitliliğine sahiptir. Bu bileşikler ilaç araştırmalarında ve tarım ürünleri geliştirmesinde kullanılmaktadır. Böylece pirazollerin sentezi için geliştirilmiş metotlar daha önemli hale gelmektedir.20986