16372 research outputs found
Sort by
An Intestine based Bio-Compatible Humidity Sensor for Environmental and Medical Measurements
No full textThe bio-compatible devices suitable for recycling and bio-degrading can be achieved with organic materials in nature. In this work, a bio-compatible capacitive humidity sensor is presented for reducing the amount of electronic waste and contributing to the sustainability of natural resources and the future. The sensor consists of 3 layers. The first layer is the processed intestine layer of cattle. Bio-compatibility is achieved with this layer. In addition to being a highly absorbing tissue, the intestine has been used for centuries for long-term preservation of meat based food. Correspondingly, the developed sensor is found to be more durable and long-lasting than other natural-material based humidity sensors in the literature. The other layers of the sensor are interdigitated copper electrodes and a 0.2 mm thick thin film strip. Thin film strip increases mechanical strength as well as flexibility. The developed sensor prototype was subjected to various tests in the humidity range of 20%-90%. In these tests, the hysteresis characteristic of the sensor, its response-recovery time, and its long-term stability and short-term step responses were examined. Moreover, as a possible application in medicine, the sensor can be used to detect breathing cycles. The sensor’s response and recovery times were measured as 8.72’ and 4.47’, respectively, possibly attributed to the stabilization of our test setup, while the sensor successfully detected deep, normal and fast breathing. Despite being kept in an uncontrolled environment, the sensor continued to operate consistently for breath measurements after 56 weeks, which is more than a year. IEE
Synthesis of benzofuran-based benzimidazole compounds andinvestigation of their antidiabetic effects
Get PDFBu tez çalışması kapsamında öncelikle 2-aril-4,6-dimetil ve 2-aril-4,6-dimetoksi benzofuran bileşiklerinin sentezlenmiş daha sonra bu sentezlenen öncü bileşikler Vilsmeier-Haack reaksiyonuna tabi tutularak seçici olarak C3 ve C7 pozisyonlarına aldehit grubunun eklenmiştir. Sentez kısmının son aşamasında aldehit fonksiyonel grubuna sahip benzofuran bileşikleri ticari olarak satın alınabilen farklı o-fenil diaminler ile reaksiyona sokularak hedef ürünler olan benzofuran temelli benzimidazol bileşikleri sentezlenmiştir. Tezin ikinci bölümü ise; sentezlenen benzofuran temelli benzimidazol hibrit bileşiklerin in-vitro α-amilaz ve α- glukozidaz enzim inhibisyonlarının incelemesini içermektedir. Bu iki enzimin inhibisyonu Tip 2-diyabet mellitus hastalığında kan glukoz seviyesini düşürüp kontrol altına almada etkin olarak kullanılan bir terapötik yaklaşımdır. Bu enzimlerin seçilmesinde farklı benzofuran türevlerinin bu iki enzimin potent inhibitörleri olduğunu gösteren literatür örnekleri etkili olmuştur.Sentezi yapılan bileşiklerin karakterizasyonları ise 1 H NMR, 13 C NMR, IR ve kütle spektrometresi yöntemleri kullanılarak yapıldı.Uygun kristaller elde edilen bileşiklerin ise X-ray kristalografi yöntemi kullanılarak yapıları aydınlatıldı.Within the scope of this thesis study, firstly 2-aryl-4,6-dimethyl and 2-aryl-4,6-dimethoxy benzofuran compounds were synthesized, and then these precursors were subjected to the Vilsmeier-Haack reaction and the aldehyde group was selectively added to the C3 and C7 positions. In the last part of the synthesis, benzofuran compounds with aldehyde functional group were reacted with different commercially available o-phenyl diamines to synthesize the target products, benzofuran-based benzimidazole compounds.The second part of the Project includes examination of in-vitro α-amylase and α-glucosidase enzyme inhibition of synthesized benzofuran-based benzimidazoles. Inhibition of these two enzymes is an effective therapeutic approach in reducing and controlling blood glucose levels in Type 2-Diabetes mellitus. The selection of enzymes was influenced by literature examples showing that different benzofuran derivatives are potent inhibitors of these two enzymes.The synthesized compounds were characterized by utilizing several methods including 1 H NMR, 13 C NMR, IR, and mass spectroscopy. When the appropriate crystals were obtained, the analysis of the synthesized compounds were elucidated using the X-ray crystallography method
The Effects of Breed and Body Mass Index on the Incidence of Arrested Laying Associated with Polycystic Ovarian Syndrome in Geese
No full textThis exploratory study aimed to investigate the effects of breed and body mass index (BMI) on arrested -laying (AL) associated with polycystic ovarian syndrome (AL-PCOS) in geese. Moreover, detailed pathological assessments in geese with AL were also performed. Mast geese and Large gray geese were reared under intensive feeding conditions. Observations during the laying season showed that all AL cases (n:8) (7.84%) were in Mast geese (n:102) fed with energy and protein -dense feeds. Necropsy revealed that all Mast geese with AL also had PCOS (8/8). In Mast geese, a significant difference was observed in body weight (BW) (p<0.0001) and BMI (p<0.0001) between the AL-PCOS group and the regular laying group. Follicle classifications detected by necropsy in AL-PCOS geese showed that among the Mast geese with AL-PCOS (n=8), two had atretic and cystic follicles (25%), four had type -1 and type -2 follicles (50%), and two had necrotic type -3 follicles (25%). The research data revealed that AL-PCOS might be correlated with breed and BMI, and that overfeeding and high BMI might increase AL- PCOS in breeds with high egg production, such as Mast geese. Therefore, it is crucial for farms raising high -yielding breeds such as Mast geese to strictly follow the laying periods and feeding regimes for high profitability. No previous reports had ever investigated AL-PCOS in geese, making this study the first of its kind. Moreover, the current study is also among the few presenting data on geese reproductive physiology and pathology
Effect of Relative Density on Microstructure, Corrosion Resistance and Mechanical Performance of Porous Ti–20Zr Alloys Fabricated by Powder Metallurgy
No full textThe microstructure, corrosion resistance and mechanical properties of a binary Ti–20Zr (at. %) alloy with differing porosities were investigated. The alloys were produced following a standard powder metallurgy with sintering at 1200 °C for 4, 6, and 8 h. A space holder agent was used to obtain two ranges of relative density, i.e., 74.8–89.3% and 54.6–66.7%. Metallographic examinations were conducted by using optical microscopy and scanning electron microscopy. The confirmation of chemical composition was performed by energy dispersive spectrometry and elemental mapping analysis. Electron backscatter diffraction analysis was conducted to investigate microstructure morphology. Phase identifications were detected by X-ray diffraction. Uniaxial compressive tests were carried out and also potentiodynamic polarization was employed to understand the corrosion performances of the alloys. Experimental results showed that the pore size and pore connectivity were able to be controlled by the sintering time and a fixed amount of space holder agent. The phase constituents of the alloys were characterized as a mixture of predominant hcp ? phase and some distorted hcp ?? phase. As foreseen, the ultimate compressive strength and elastic modulus of the alloys increased with increasing relative density. Results of corrosion resistance revealed adding space holder reduced the polarization resistance of Ti–20Zr (at. %) sintered for 6 h from 15.4 to 14.09 ?. However, volume fraction of general porosity did not affect the microstructure of the alloys. In conclusion, the relative density of the alloys achieved in this study played a crucial role on the mechanical properties and corrosion properties. © King Fahd University of Petroleum & Minerals 2023
KENDİNİ MÜKEMMELİYETÇİ GÖSTERME EĞİLİMİ İLE KİŞİLERARASI DUYARLILIK ARASINDAKİ İLİŞKİNİN İNCELENMESİ
No full textBu araştırmada kendini mükemmeliyetçi gösterme eğilimi ile kişilerarası duyarlılık arasındaki ilişki bazı değişkenlere göre incelenmiştir. Araştırma kapsamında çeşitli üniversitelerde 2021-2022 öğretim yılında öğrenim gören 154’ü kadın 146’sı erkek olmak üzere toplam 300 üniversite öğrencisinden Demografik Bilgiler Formu, Kendini Mükemmeliyetçi Gösterme Eğilimi Ölçeği ve Kişilerarası Duyarlılık Ölçeği aracılığı ile veri toplanmıştır. İlişkisel tarama modeli kullanılan bu çalışmanın verileri analiz edildiğinde kendini mükemmeliyetçi gösterme eğilimi ile kişilerarası duyarlılık arasında anlamlı bir ilişki bulunmuştur. Bunun yanı sıra kişilerarası duyarlılığın kendini mükemmeliyetçi gösterme eğilimini yordadığı da bulgular arasındadır. Diğer yandan kendini mükemmeliyetçi gösterme eğilimi ile kişilerarası duyarlılık arasındaki ilişkinin sosyoekonomik düzeye göre farklılaştığı tespit edilirken; cinsiyete, yaşa ve yerleşim yerine göre bir farklılaşmanın olmadığı saptanmıştır. Çalışmada ulaşılan bulgular güncel alanyazın ışığında tartışılmıştır ve ilgili araştırmacılar ile alan çalışanlarına önerilerde bulunulmuştur
Which is a Better Predictor for the Safety and Efficacy of Retrograde Intrarenal Surgery; Stone Size or Volume? A Study of RIRsearch Study Group
No full textObjective: To compare the predictive effects of stone size and volume on the efficacy and safety of retrograde intrarenal surgery (RIRS) and to determine the cutoff values of stone volume for prediction of RIRS efficacy and safety. Methods: Patients who underwent RIRS between 2017 and 2021 in six referral centers were retrospectively included in the study. The database of the RIRsearch group, which was formed prospectively, was used for this retrospective analysis. The surgical results and complications of RIRS were evaluated according to stone size and stone volume and compared between these groups. Results: A total of 1128 patients were included. Operation time, intraoperative complication rate, and postoperative complication rate increased significantly as stone size and stone volume increased (P < .05). Stone size and volume were significant indicators for stone-free rates, but pairwise comparison showed that stone volume was a significantly better predictor of surgical success compared with stone size (P < .001). Stone size was not sufficient to predict postoperative complications, whereas stone volume predicted these complications with low performance. Conclusions: Stone volume was a better predictor for surgical success than stone size, and it was as reliable as stone size in predicting postoperative complications
Influence of nucleating agent on the mechanical and thermal properties of neat isotactic polypropylene/reprocessed polypropylene blends
No full textIn recent years, recycling of polypropylene (PP) has gained significant attention for various industrial applications, namely post-industrial PP waste has great advantages in terms of circular economy. In this study, the effect of the amount of nucleating agent on the mechanical and thermal properties of polypropylene blends was investigated. Neat isotactic polypropylene and reprocessed polypropylene (iPP/rPP) were blended by means of a twin-screw extruder at 0/100, 50/50, 25/75 and 100/0% (by weight), respectively. The blends were processed by means of a twin-screw extruder then injection molded with the nucleating agent at different ratios (0, 1, 3 and 6% by weight). The properties of the samples were investigated by melt flow index (MFI) measurement, scanning electron microscope (SEM), tensile test, three point bending test and differential scanning calorimetry (DSC) analysis. The MFI values of the blends increased with the increasing amount of rPP. As a result of DSC analysis, the melting temperature of the blends increased by 1.4 degrees C with the presence of 6% (by weight) nucleating agent. The highest flexural modulus was obtained as 1863 MPa for the iPP/rPP0 blends with the addition of 6% (by weight) nucleating agent. The elastic modulus increased with the addition of nucleating agent from 1819 (iPP/rPP50NA0) to 2152 MPa (iPP/rPP50NA6). The iPP/rPP blend with a weight ratio of (50/50) exhibited mechanical and thermal properties similar to neat iPP with the presence of 3% (by weight) nucleating agent
Investigation of Electromagnetic Wave Propagation in Nanocones
No full textThe aim of this thorough study is to investigate the behaviour of electromagnetic wave propagation in three distinct nanostructures, each with unique shapes and material compositions. The first nanostructure under scrutiny is a butterfly-shaped nanocone formed by placing two nanostructures side by side. It consists of two nanocons. The second nanostructure is a deltoid-shaped nanocone created in a similar manner, composed of two different nanocones. The third nanostructure is a parallelogram-shaped nanocone constructed by stacking nanocones on each other and made of two different nanocones. These nanostructures differ in shape and material property parameters, each comprising two different materials with specific permeability and permittivity values. To conduct a detailed analysis, the study utilises the nonlocal theory to examine the electromagnetic wave propagation behaviour in these nanostructures. The focus of the analysis is on the travel and reflection of electromagnetic waves at three specific points along the same axis in each structure, allowing for a comprehensive comparison of their behaviours. This in-depth investigation holds significant importance as it seeks to understand the penetration and subsequent propagation of incident electromagnetic waves within nanostructures of varying shapes and material compositions, shedding light on their potential applications in advanced technology and optic science. © IJCESEN
NÜFUS COĞRAFYASI AÇISINDAN TÜRKİYE CUMHURİYETİ'NİN İLK NÜFUS SAYIMINA GÖRE TÜRKİYE VE BİLECİK İLİNE BİR BAKIŞ
No full textBelirli bir yerde yaşayan insan nüfusunun çeşitli özelliklerinin tespiti için belirli dönemler içerisinde nüfus sayımları yapılmaktadır. 1927 yılında yapılan genel nüfus sayımı Türkiye Cumhuriyeti’nin ilk nüfus sayımıdır. Osmanlı Devleti Döneminde nüfus sayımları yapılmış olsa da Türkiye nüfusu hakkında ilk detaylı bilgiler 1927 yılı genel nüfus sayımıyla ortaya çıkmıştır. Bu genel nüfus sayımında Türkiye’nin diğer illerinde olduğu gibi Bilecik ili nüfusunun da özellikleri detaylı şekilde tespit edilmiştir. Nüfusun cinsiyete, yaş aralığına, okur-yazarlığa, medeni hale, mesleklere, konuşulan anadillere, uyruklarına, doğum yerlerine, dini inançlara ve sakatlık-engellilik durumlarına göre tespiti ve tasnifi yapılmıştır. Bu özellikler ilçeler düzeyinde de belirlenmiştir. Bu çalışmanın amacı, Türkiye Cumhuriyeti Devleti’nin ilk genel nüfus sayımı olan 1927 genel nüfus sayımı sonuçlarına göre Türkiye geneli ve Bilecik ilinde tespit edilen nüfus özelliklerini incelemek, değerlendirmek ve nüfus özellikleriyle ilgili olarak coğrafya biliminin sebep-sonuç, bağlantı ve dağılış ilkeleri kapsamında yorumlamalar gerçekleştirmek ve sonuçlar ortaya koymaktır. Yapılan çalışmanın aynı zamanda daha sonra ilgili olarak yapılacak coğrafi çalışmalara öncülük etmesi amaçlanmıştır. Yapılan çalışmada gerekli kaynaklardan yararlanılarak nüfusun detaylı özellikleri gerek Türkiye genelinde gerekse Bilecik ili özelinde incelenmiş, veriler tablolar ile gruplandırılarak değerlendirilmiştir. Coğrafya biliminin sebep-sonuç ve bağlantı ilkeleri kapsamında Bilecik ili nüfus özellikleri Türkiye geneliyle karşılaştırılarak kıyaslamalar yapılmış ve yorumlar gerçekleştirilmiştir. 1927 yılındaki genel nüfus sayımı neticesine göre Bilecik ilinde nüfusun özellikleri genel olarak değerlendirildiğinde il genelinde nüfus özelliklerine ait değerlerin Türkiye ortalamasından yüksek oranlarda olması, o zamanki şartlarda Bilecik ilinin Türkiye’nin birçok iline göre daha iyi durumda olduğunu ortaya koymuştur
Impact of oral isotretinoin on the inflammatory markers: can lymphocyte/HDL-C and platelet/HDL-C ratios be new indicators of inflammation in acne vulgaris patients?
No full textIntroduction: The effect of isotretinoin on inflammatory markers has been reported with conflicting results. No studies have been reported on the relationship between isotretinoin and lymphocyte/high-density lipoprotein cholesterol [HDL-C] ratio (LHR), neutrophil/HDL-C ratio (NHR), or platelet/HDL-C ratio (PHR) in acne patients. Objectives: We aimed to investigate how isotretinoin affects the inflammatory markers, including LHR, NHR, and PHR, in acne vulgaris patients. Methods: A total of 361 patients with moderate-to-severe acne vulgaris who received systemic isotretinoin for at least six months were included. Complete blood count and biochemical analyses, including monocyte/HDL-C ratio (MHR), NHR, LHR, PHR, neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio (MLR), platelet/lymphocyte ratio (PLR), the aggregate index of systemic inflammation (AISI), systemic immune-inflammation index (SII), and systemic inflammation response index (SIRI), obtained at the treatment onset and the end of the first, third, and sixth months of treatment were investigated. Results: There was no significant difference in MHR and NHR levels between repeated measures. A significant increasing trend was seen in LHR and PHR (P = 0.001 and P = 0.011, respectively). HDL-C levels gradually and significantly declined during the six months (P < 0.001). Serum NLR, derived NLR, SII, SIRI, MLR, and AISI showed a significant decrease in line with clinical improvement in acne during the six months of therapy (P < 0.05). Conclusions: Declining levels of NLR, MLR, SII, SIRI, and AISI may indicate the anti-inflammatory effects of isotretinoin on the pilosebaceous unit, whereas increasing levels of LHR and PHR may show systemic inflammatory activity of isotretinoin