Orta Anadolu'daki PV modüllerinin uzun vadeli performans ve bozulma oranları

Outdoor tests of photovoltaic modules are crucial for the market, and technological development. It is vital for manufacturers and researchers to conduct tests not only in the long term but also in different climatic conditions. In this thesis, 12 modules are tested in Middle Anatolia climate conditions for nine years in three different module groups, which are mono-crystalline (Mono-Si-1 & 2 & 3, Bifi-Mono-Si, HIT), polycrystalline (Poly-Si-1 & 2), and thin films (CIS-1 & 2, CIGS-1 & 2, µSi/a-Si). We analyzed the efficiencies of solar PV modules with nine years of data ollected from Middle Anatolia. The most effective module is the Bifi-Mono-Si with 16.47 % as expected and the second effective module is HIT with 14.82 % efficiency. In addition to efficiencies, performance ratios are investigated and Mono-Si-1 has the highest performance ratio on average. Furthermore, we analyzed the weather corrected performance ratio of 5 modules (CIS-1 & 2, µSi/a-Si, HIT, Poly-Si-2) and the HIT module obtains the best corrected performance ratio on average. Finally, we utilized efficiencies and performances ratio values to estimate the egradation rates of solar PV modules. We found the following degradation rates for modules: 0.80 %/year for Mono-Si modules, 1.95%/year for CIS modules, 0.68 %/year for a-Si, 1.42 %/year for Poly-Si, and 1.09 %/year for HIT module. Considering all results, Mono-Si is the best option for long-term usage and development.Fotovoltaik modüllerin açık hava testi, ¸sirketler ve teknolojik geli¸sme için çok önemlidir. Testlerin sadece uzun vadede degil, farklı iklim ko¸sullarında da yapılması üreticiler ve ara¸stırmacılar için hayati önem ta¸sımaktadır. Bu tez çalı¸smasında 12 modül monokristal (Mono-Si-1 & 2 & 3, Bifi-Mono-Si, HIT), polikristal (Poly-Si-1 & 2) ve ince filmler (CIS-1 & 2, CIGS-1 & 2, µSi/a-Si) olmak üzere üç farklı grup modül kullanılarak yakla¸sık dokuz yıl boyunca Orta Anadolu iklim ko¸sullarında test edilmistir. Güne¸s PV modüllerinin verimliliklerini Orta Anadolu’dan toplanan dokuz yıllık verilerle analiz ettik. En verimli modül beklendigi gibi % 16,47 ile Bifi-Mono-Si ve ikinci verimli modül ise %14,82 verimlilik ile HIT’dir. Verimliliklerin yanı sıra performans oranlarını ara¸stırdık ve Mono-Si-1 ortalama olarak en yüksek performans oranına sahip oldugu tespit ettik. Ayrıca, 5 modülün (CIS-1 & 2, ˘ µSi/a-Si, HIT, Poly-Si-2) hava ko¸sullarına göre düzeltilmi¸s performans oranını analiz ettik ve HIT modülü ortalama olarak en iyi düzeltilmi¸s performans oranına sahip oldu. Son olarak, güne¸s PV modüllerinin bozulma oranlarını tahmin etmek için verimlilik ve erformans oranı degerlerini kullandık. Modüller için ¸su bozulma oranlarını bulduk: Mono-Si modülleri için 0,80 %/yıl, CIS modülleri için 1,95%/yıl, a-Si için 0,68 %/yıl, Poly-Si için 1,42 %/yıl ve HIT modülü için 1,09 %/yıl. Tüm sonuçlar göz önüne alındıgında Mono-Si, uzun süreli kullanım ve geli¸stirme için en iyi seçenek olarak kar¸sımıza çıkmaktadır.M.S. - Master of Scienc

Association between birth-weight and blood pressure as well as birth-weight and salt-sensitivity in healthy volunteers during sodium intake

Die Salzsensitivität (stärkere Beeinflussbarkeit des Blutdrucks durch veränderte Kochsalzaufnahme) kann bei Patienten mit arterieller Hypertonie und Normotonikern beobachtet werden. Zur Pathogenese der arteriellen Hypertonie beschreibt u.a. die Barker-Hypothese einen inversen Zusammenhang zwischen niedrigem Geburtsgewicht und der arteriellen Hypertonie im Erwachsenenalter. Um den Zusammenhang zwischen Geburtsgewicht und Salzsensitivität zu untersuchen, wurden in dieser Studie junge, männliche und normotone Probanden, die über 14 Tage in einer einfachblinden, randomisierten Reihenfolge eine kochsalzarme Kost und und zusätzlich jeweils 7 Tage Natriumchlorid- bzw. Placebotabletten (kochsalzreiche bzw. kochsalzarme Diät) erhielten, untersucht. Zu Beginn, am 7. und 14. Tag erfolgten Blutdruck-, Herzfrequenz- und anthropometrische Messungen. Bei Abnahme des mittleren arteriellen Blutdrucks um mehr als 3mmHg wurden die Probanden als salzsensitiv bezeichnet. Es zeigte sich keine signifikante Korrelation zwischen Geburtsgewicht und den Kreislaufparametern vor und während der Diät. Die Differenzen der Kreislaufparameter während der Diät zeigten eine signifikante Korrelation zwischen systolischem Blutdruck und Geburtsgewicht sowie zwischen Herzfrequenz und Geburtsgewicht. Unter diätetischer Kochsalzrestriktion konnten von 154 Probanden 29 als salzsensitive Normotoniker beschrieben werden. Vier dieser salzsensitiven Normotoniker hatten ein Geburtsgewicht <3000g. Es bestand eine signifikante Korrelation zwischen Geburtsgewicht und den anthropometrischen Daten. Die Ergebnisse dieser Untersuchung zeigten keine Bestätigung der Barker-Hypothese und keine Bestätigung einer Korrelation zwischen niedrigem Geburtsgewicht und der Eigenschaft Salzsensitivität. Probanden mit einem relativ hohen Geburtsgewicht reagierten hingegen in der salzreichen Phase der Diät mit einem statistisch signifikanten Anstieg des systolischen Blutdrucks. Präventive Maßnahmen, die diesen Zusammenhang berücksichtigten, könnten möglicherweise zur Reduzierung des hypertensiven Risikos beitragen und wären somit von klinischer Bedeutung.Salt sensitivity (i.e. increase in blood pressure following a high-salt meal) may be observed in patients with arterial hypertension and normotensive people. The Barker hypothesis describes an inverse relationship between low birth-weight and arterial hypertension in adults. To investigate the association between birth-weight and salt sensitivity, young, male and healthy volunteers received low-salt meal and sodium- or placebo-tablets over 14 days in a single blind randomized study. Body measurements related-data have been collected at specific dates. The results did not show a significant association between birth-weight and blood pressure as well as heart frequency before and over the whole study duration. In contrast, the differences of the birth-weight and systolic blood pressure values were significantly associated with birth-weight. Out of the 154 healthy volunteers 29 were classified as saltsensitive. Thereof 4 volunteers had a birth-weight lower then 3000g. A significant association between birth-weight and body measurements related- data was shown. The results of this study did not support the Barker hypothesis and the association between low birth-weight and salt sensitivity, whereas volunteers with high birth-weight developed a statistically significant increase in systolic blood pressure during the high-salt intake. Preventive measures taking into account this association might be reducing the risk of hypertension and, thus, might be of clinical relevance

Protective Effect of Vitamin E on Gastric Mucosal Injury in Rats with Biliary Obstruction

Patients with liver disease display increased susceptibility to gastric mucosal damage. A role of free radicals has been suggested in the development of gastric mucosal damage in normal subjects. The effects of antioxidant vitamin E treatment on the liver and stomach in cirrhotic rats were examined. Fifty rats were divided into three groups. Cirrhosis was induced by bile duct ligation in 40 of 50 rats. Controls underwent a sham operation. Gastric mucosal lesions were produced by intragastric administration of 1 mL of 95% ethanol in all three groups. Twenty bile duct-ligated rats were injected intramuscularly with vitamin E (100 mg/kg/day). Liver and stomach histology, and stomach malondialdehyde and glutathione levels were determined. Portal hypertension was measured. Macroscopic and microscopic gastric mucosal injury were significantly greater in the control and common bile duct-ligated groups than in the vitamin E-pretreated group (P<0.05). The tissue malondialdehyde and glutathione levels were significantly decreased in the vitamin E-administrated group compared with the common bile duct-ligated group (P<0.001). Vitamin E administration may be cytoprotective for both the liver and gastric mucosa in bile duct-ligated rats

The role of L-arginine and neutrophils on incisional wound healing

Although arginine plays an important role in many aspects of inflammation and wound healing, the mechanism is not clear. We aimed to evaluate the effect of L-arginine administration on wound healing and neutrophil activity and on the interaction of these effects. Sixteen rats were divided into two groups: control group and L-arginine group. L-arginine was given intraperitoneally. The rats underwent incisional wounding and were killed on the 7th day of wounding. Blood neutrophil counts, neutrophil adhesivity index, tensile strengths and hydroxyproline level of skin were determined, histopathological and electron microscopical evaluation of healing was performed. Wound scores in the control group were significantly lower (p < 0.05). Hydroxyproline and collagen levels of skin were significantly increased in the L-arginine group (p < 0.05). Blood neutrophil counts and neutrophil adhesivity index in the L-arginine group were significantly increased (p < 0.05), as were the inflammatory cells in the skin. L-arginine may be used during the first phase of healing to induce inflammation in high risk patients. © 2001 Lippincott Williams & Wilkins, Inc

The Role Of Neutrophils In The Formation Of Peritoneal Adhesions

The most common cause of intraperitoneal adhesions which may result in infertility and intestinal obstruction is previous abdominal surgery. Surgical trauma of the peritoneum in the absence of infection elicits a rapid and transient influx of polymorphonuclear leukocytes (PMN) into the peritoneal cavity, The role of neutrophils in intraperitoneal adhesion formation has not been studied. We aimed to study the effects of PMN counts and PMN functions on peritoneal adhesion formation. Forty peritoneal adhesion-induced rats were randomly divided into three groups; group I, receiving saline; group LI, receiving cyclophosphamide; and group III, receiving granulocyte-macrophage colony-stimulating factor (GM-CSF), In all groups, peritoneal lavage was performed to determine PMN counts the day after adhesion induction. Blood neutrophil counts and neutrophil functions were also determined. Adhesions were evaluated blindly 14 days after the operation. Adhesion tissue samples were microscopically evaluated. Tissue hydroxyproline and collagen concentrations were measured. The neutrophil counts and phagocytosis significantly increased in group III and neutrophil counts decreased in group II (P < 0.05), The score of adhesion formation in group II was significantly less than that in groups I and III (P < 0.05). Hydroxyproline concentrations of adhesion tissue were significantly decreased in group II when compared with group III (P < 0.05). The present study shows that neutropenia lowers the degree of postoperative adhesion formation. It is concluded that PMN may have a role to play in modulating post-operative adhesion formation.WoSScopu

Türkiye’de Yapılan Argümantasyon Temelli Matematik Öğretiminin Öğrencilerin Başarılarına Etkisinin Meta-Analiz ile İncelenmesi

Argümantasyon temelli öğretim ile öğrenciler kavramlarla ilgili tartışma yapma, veri toplama, argüman oluşturma ve savunma imkânı bulmaktadırlar. Yapılan araştırmalar bu öğretim yönteminin matematik öğretimine olumlu etkileri olduğunu göstermektedir. Bu araştırmada argümantasyon temelli matematik öğretiminin öğrencilerin matematik başarısı üzerindeki etkisinin ortaya koyulması amaçlanmaktadır. Bu amaç doğrultusunda Türkiye’de argümantasyon temelli matematik öğretim ile ilgili yapılan çift gruplu deneysel çalışmalar meta-analiz yöntemi aracılığıyla incelenerek, YÖK Ulusal Tez Merkezi, Ulakbim, ERIC ve Google Akademik veri tabanları, “argümantasyon”, “matematik” ve “geometri” anahtar kelimeleri kullanılarak taranmıştır. Alanyazın taraması sonucunda araştırmanın ölçütlerine uygun olarak 2015-2020 yılları arasında yapılmış beşi tez ve üçü makale olmak üzere toplam sekiz çalışmaya ulaşılmıştır. Meta-analiz sonucunda argümantasyon temelli matematik öğretiminin geleneksel öğretim yöntemlerine göre öğrencilerin matematik derslerindeki akademik başarılarına istatistiksel olarak anlamlı ve yüksek düzeyde etkisinin olduğu belirlenmiştir. Ayrıca yayın türü, öğrenim kademesi ve konu alanı için yapılan moderatör analizleri sonucunda gruplar arası etki büyüklükleri hesaplanmış ve istatistiksel olarak anlamlı bir farklılık olmadığı görülmüştür. Ülkemizde bu alandaki çalışmalarda eksiklikler olması nedeniyle farklı öğrenci grupları ve farklı sınıf seviyelerinde yapılacak çalışmaların hem ulusal hem de uluslararası alana katkı sağlayacağı düşünülmektedir.Students can obtain the opportunity to discuss on the concepts, collect data, mount an argument and justify that argument thanks to Argumentation Based Mathematics Teaching. The studies show that this teaching method has positive effects on mathematics teaching. This research aims to reveal the effect of Argumentation Based Mathematics Teaching on mathematics achievement of students. For this purpose, two-group experimental studies on Argumentation-Based Mathematics Teaching in Turkey were examined through meta-analysis method. In order to access these studies, CoHE National Thesis Center, Ulakbim, ERIC and Google Scholar databases were searched using the keywords "argumentation", "mathematics" and "geometry". As a result of the literature review, in accordance with the purpose of the research, a total of eight studies, five theses and three articles, were reached between the years 2015-2020. Consequently, it was determined that Argumentation-Based Mathematics Teaching had a high and statistically significant effect on the academic achievement of students in mathematics compared to traditional teaching methods. In addition, as a result of the moderator analyzes for the type of publication, education level and the subject of the course, the effect quantities between the groups were calculated and it was seen that there was not a statistically significant difference. Due to the deficiencies in the research in this field in our country, it is considered that the studies to be carried out in different student groups and different grade levels will contribute to both national and international fields