Characterization and modification of antioxidant proteins from plat materials

Thesis (Master)--İzmir Institute of Technology, Biotechnology and Bioengineering, İzmir, 2005Includes bibliographical references (leaves: 73-75)Text in English; Abstract: Turkish and Englishxiv, 92 leavesIn this study, the radical scavenging and iron chelating capacity of proteins from heat treated (20 min at 90 oC) or thermally processed (20 min at 121 oC) chick-peas andkidney-beans were compared. Lyophilized crude protein extracts from chick-peas contained more protein (1.5-3 fold) and showed higher free radical scavenging (up to 2.3 fold) and iron binding capacity (up to 3 fold) than lyophilized crude protein extracts form kidney-beans. The thermal processing of chick-peas did not cause a significant change in the radical scavenging capacity of their lyophilized crude protein extracts, but improved the iron chelating capacity of these proteins almost 80 %. However, the thermal processing reduced both the radical scavenging and iron binding capacity of crude lyophilized proteins form kidney beans by 20-40 % and 60 %, respectively.Partial purification by ammonium sulfate precipitation or DEAE-cellulose chromatography increased the antioxidant capacity of thermally processed chick-pea proteins. The DEAE cellulose chromatography also showed the presence of 5 and 3 antioxidant protein fractions in heat treated and thermally processed chick-peas, respectively. Hot acidic hydrolysis at 80 oC for 30 min in presence of 1.5 M HCl increases the specific antioxidant activity of protein extracts, but causes the formation of undesired Maillard reaction products. Hot extraction at 85 oC for 30 min at pH 2.5 extracts the antioxidant proteins selectively, whereas 85 oC for 30 min at pH 9.5 extracts both antioxidant proteins and other proteins

Yüksek Dayanım Ve Şekil Değiştirme Özellikli Çeliklerin Kolon Kesitinde Donatı Olarak Kullanımı

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Bu çalışmada yüksek dayanım ve şekildeğiştirme özellikli çeliklerin betonarme kolon kesitinde donatı olarak kullanımı analitik olarak incelenmiştir. Çalışma kapsamında analitik olarak, yüksek dayanım ve süneklik özelliklerine sahip olan, “YSÇ” adı verilmiş betonarme çeliği kullanılarak analitik olarak tanımlanan betonarme kolonların, davranışı, ülkemizin inşaat mühendisliği yapılarında yaygın olarak kullanılan BÇIIIa betonarme çeliği ile üretilmiş elemanlar ile karşılaştırılmıştır. 1/3 ölçekli betonarme kolonların YSÇ ve BÇIIIa çelikleri ile üretilmiş olan kuramsal modelleri, COLA (Reinforced Concrete Column Analysis) programına tanımlanarak, bu program yardımıyla kesitlerin moment-eğrilik, yatay yük yerdeğiştirme ve enerji tüketme davranışları incelenmiş ve 2 farklı tip çeliğin kullanım durumunun, kesit davranışına etkileri karşılaştırılmıştır. Özellikle, “YSÇ” ile üretilen betonarme kolonlarda dayanım ve süneklik özellikleri ile birlikte, deprem performansı açısından önemli olan enerji tüketim kapasitesinin irdelenmesi amaçlanmış, analizler sonucunda YSÇ ve BÇIII çeliklerini içeren betonarme elemanlar, bu parametreler gözönünde bulundurularak karşılaştırılmıştır.One of the most important characteristics of a structure which is in earthquake regions is its ductility. A better ductile behavior can be achieved by constructing these structures with elements which have high energy absorption capacities during moderate and strong earthquakes. For reinforced concrete structures the deformation capability and strength of structural steel as reinforcement has an important contribution on the entire behavior of the reinforced concrete member. In this study, use of a type of steel as reinforcement in reinforced concrete members which features high deformability capacity and high yielding strength(≈540 MPa), is analyzed analytically. These studies contain section analysis for reinforced concrete members with high strength and BCIII steel generally used in building industry of Turkey. All the analytical studies are carried out with a software called COLA (Reinforced Concrete Column Analysis). It has been found that reinforced concrete columns reinforced with high strength steel reached bigger moment and lateral load carrying capacities in comparison with the ones which are reinforced with BCIII

Molecular understanding of sterically controlled compound release through an engineered channel protein (FhuA)

<p>Abstract</p> <p>Background</p> <p>Recently we reported a nanocontainer based reduction triggered release system through an engineered transmembrane channel (FhuA Δ1-160; Onaca <it>et al</it>., 2008). Compound fluxes within the FhuA Δ1-160 channel protein are controlled sterically through labeled lysine residues (label: 3-(2-pyridyldithio)propionic-acid-N-hydroxysuccinimide-ester). Quantifying the sterical contribution of each labeled lysine would open up an opportunity for designing compound specific drug release systems.</p> <p>Results</p> <p>In total, 12 FhuA Δ1-160 variants were generated to gain insights on sterically controlled compound fluxes: Subset A) six FhuA Δ1-160 variants in which one of the six lysines in the interior of FhuA Δ1-160 was substituted to alanine and Subset B) six FhuA Δ1-160 variants in which only one lysine inside the barrel was not changed to alanine. Translocation efficiencies were quantified with the colorimetric TMB (3,3',5,5'-tetramethylbenzidine) detection system employing horseradish peroxidase (HRP). Investigation of the six subset A variants identified position K556A as sterically important. The K556A substitution increases TMB diffusion from 15 to 97 [nM]/s and reaches nearly the TMB diffusion value of the unlabeled FhuA Δ1-160 (102 [nM]/s). The prominent role of position K556 is confirmed by the corresponding subset B variant which contains only the K556 lysine in the interior of the barrel. Pyridyl labeling of K556 reduces TMB translocation to 16 [nM]/s reaching nearly background levels in liposomes (13 [nM]/s). A first B-factor analysis based on MD simulations confirmed that position K556 is the least fluctuating lysine among the six in the channel interior of FhuA Δ1-160 and therefore well suited for controlling compound fluxes through steric hindrance.</p> <p>Conclusions</p> <p>A FhuA Δ1-160 based reduction triggered release system has been shown to control the compound flux by the presence of only one inner channel sterical hindrance based on 3-(2-pyridyldithio)propionic-acid labeling (amino acid position K556). As a consequence, the release kinetic can be modulated by introducing an opportune number of hindrances. The FhuA Δ1-160 channel embedded in liposomes can be advanced to a universal and compound independent release system which allows a size selective compound release through rationally re-engineered channels.</p

Bir yangının düşündürdükleri

Taha Toros Arşivi, Dosya No: 192-Tiyatro ve Sinema Dokümanlarıİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Antioxidant activity and phenolic content of fresh and dry nuts with or without the seed coat

Total antioxidant activities based on ABTS free radical scavenging activity and phenolic content of fresh or dry hazelnuts, walnuts and pistachios assayed with their seed coats changed between 3063 and 11,076 μmol trolox equivalents/100 g d.w. and 256 and 755 mg gallic acid equivalents/100 g d.w., respectively. The walnuts used in this study showed the highest antioxidant activity, followed by pistachios and hazelnuts. The removal of seed coat reduced the total antioxidant activity of hazelnuts, walnuts and pistachios almost 36, 90 and 55%, respectively. The total antioxidant activities of investigated fresh and dry nuts are not considerably different. However, phenolic content and antioxidant activity in hydrophilic and ethanolic fractions obtained by successive extraction of nuts showed some variation. The antioxidant activity in 1-serving portion of fresh or dry walnuts is equivalent to that in almost 2-serving portions of black tea, and 1.2-1.7-serving portions of green and Earl Grey tea. One-serving portions of dry hazelnuts and fresh or dry pistachios contained antioxidant activity equivalent to that in 0.7-1-serving portions of black tea. The antioxidant activity measurements correlated with phenolic content (r2 = 0.70). This study showed the potential of using fresh or dry nuts to develop functional foods with high antioxidant activity

Relationship between levels of intercultural sensitivity and emotional intelligence amongst preservice social studies teachers

This study focused on the levels of intercultural sensitivity and emotional intelligence demonstrated by pre-service Social Studies teachers' and sought to explore the relationship between the two variables. The study used a correlational survey research design. The sample consisted of 274 pre-service Social Studies teachers who were in different years of study. The data were collected using the “Intercultural Sensitivity Scale”, “Emotional Intelligence Scale”, and a “Personal Information Form”. The data were analyzed using the independent samples T-test and one-way Analysis Of Variance (ANOVA). The correlation co-efficient was also computed to identify the relationship between intercultural sensitivity and emotional intelligence. The analysis results showed that the intercultural sensitivity of preservice Social Studies teachers' differed significantly according to gender and them having friends from different countries or cultures; while their emotional intelligence differed significantly according to having friends from different countries or cultures. A significant moderate positive correlation was found between intercultural sensitivity and emotional intelligence. Further research may contribute to the literature by studying emotional intelligence and intercultural sensitivity in sample groups from different areas or with different characteristics

Interaction Between Manufacturer\u27s Wholesale Pricing and Retailers’ Price-Matching Guarantees

In practice, many retailers employ price-matching guarantees (PMGs), committing to meet the price of an identical product at a competitor\u27s outlet. Despite the profound linkage between retailers and manufacturers, existing literature has predominantly explored retailers\u27 PMGs without contemplating the influence of manufacturers\u27 wholesale pricing strategies. Employing a supply chain model comprising one manufacturer and two retailers, we scrutinize the implications of wholesale pricing—uniform or discriminatory—on supply chain members and consumers when retailers have the option to extend PMGs. Our analysis uncovers that retailers refrain from offering PMGs when the manufacturer is granted the discretion to set discriminatory wholesale prices—even if such offers align with the manufacturer\u27s preferences. Conversely, under uniform wholesale pricing, PMGs thrive at equilibrium—even if the manufacturer opposes the practice—as long as the degree of demand or cost asymmetry between retailers and average hassle costs remains relatively modest. Although firms\u27 preferences regarding PMGs vary, a Pareto zone exists where all entities prefer that either the efficient retailer under demand asymmetry or the inefficient retailer under cost asymmetry extends the PMG. Despite the potential advantages of PMGs for the more efficient retailer, the enforcement of uniform wholesale pricing diminishes supply chain profit, consumer welfare, and overall social welfare. The detrimental impacts on welfare owing to the imposition of uniform wholesale pricing persist, even amid the presence of hassle costs associated with price matching. Our findings thus instigate a dialogue for policymakers concerning the validity of regulating wholesale pricing when PMGs are in effect