Degradation kinetics of ergosterol in tomato paste serum

Thermal degradation of ergosterol in tomato paste serum was studied at different pH (4.5, 4.3, 3.9, 3.7 and 3.5,) and heating periods (0, 10, 20, 30 and 50 min) over the temperature range of 70 to 95 °C. Analysis of kinetic data suggested a first-order reaction for the degradation of ergosterol with the half-lives of 301.4–36.7, 239.0–33.7, 203.9–29.6, 113.6–29.8 and 83.5–23.7 min for 4.5, 4.3, 3.9, 3.7 and 3.5 pH samples, respectively, between 70 and 95 °C. Temperature dependence of reaction was described by the Arrhenius relationship. Activation energies for 4.5, 4.3, 3.9, 3.7 and 3.5 pH samples were found 20.57, 19.62, 19.07, 12.41 and 11.08 kcal mol⁻¹, respectively, between 70 and 95 °C.     

Nutrient composition of hazelnut (Corylus avellana L.) varieties cultivated in Turkey

In this study, chemical composition of the 17 different hazelnut varieties grown in the Black Sea Region of Turkey was investigated. The main fatty acids in hazelnut varieties were oleic (79.4%), linoleic (13.0%) and palmitic acid (5.4%). The ratios of polyunsaturated/saturated and unsaturated/saturated fatty acids of hazelnuts varieties were found to be between 1.23 and 2.87, and 11.1 and 16.4, respectively. The average niacin, vitamin B₁, vitamin B₂, vitamin B₆, ascorbic acid, folic acid, retinol and total tocopherol contents of hazelnut kernels were 1.45 mg/100 g, 0.28 mg/100 g, 0.05 mg/100 g, 0.5 mg/100 g, 2.45 mg/100 g, 0.043 mg/100 g, 3.25 mg/100 g and 26.9 mg/100 g, respectively. The amount of the essential amino acids, mostly as arginine (2003 mg/100 g) and leucine (1150 mg/100 g), and the non-essential amino acids, mostly as glutamic acid (2714 mg/100 g) and aspartic acid (1493 mg/100 g) were also determined in the hazelnut varieties. Mineral compositions of the hazelnut varieties, e.g., K, Mn, Mg, Ca, Fe, Zn, Na and Cu were (averagely) measured as 863 mg/100 g, 186 mg/100 g, 173 mg/100 g, 5.6 mg/100 g, 4.2 mg/100 g, 2.9 mg/100 g, 2.6 mg/100 g and 2.3 mg/100 g, respectively.     

The sustainability indicators of power production systems

One of the most important elements of economical and social development is to provide uninterrupted electric energy to consumers. The increasing world population and technological developments rapidly increase the demand on electric energy. In order to meet the increasing demand for sustainable development, it is necessary to use the consumable resources of the world in the most productive manner and minimum level and to keep its negative effects on human health and environment in the lowest level as much as possible. In this study, alignment of hydrogen fuel cells, hydroelectric, wind, solar and geothermal sourced electric energy systems, in addition to fossil fueled coal, natural gas and nuclear power plants, in respect to sustainability parameters such as CO₂ emission, land use, energy output, fresh water consumption and environmental and social effects is researched. Consequently, it has been determined that the wind and nuclear energy power plants have the highest sustainability indicators. The fuel cells that use hydrogen obtained by using coal and natural gas are determined as the most disadvantageous transformation technologies in respect to sustainability. This study contains an alignment related to today's technologies. Using of renewable energy resources especially in production of hydrogen, output increases to be ensured with nanotechnology applications in photovoltaic systems may change this alignment.     

Changes in pigment profile and surface colour of fig (Ficus carica L.) during drying

In this study, anthocyanins in three fresh fig varieties (Ficus carica L.) cultivated in Turkey were characterised and quantified by HPLC/DAD and HPLC/MS. In addition, the carotenoid composition of Sar?lop and Sar?zeybek, yellow fig varieties, was determined, and then the ripening‐ and drying‐related changes in carotenoids and surface colour of figs were monitored during conventional sun‐drying. Four different anthocyanins, cyanidin‐3‐glucoside, cyanidin‐3,5‐diglucoside, cyanidin‐3‐rutinoside (major anthocyanin) and pelargonidin‐3‐glucoside, were identified in samples. Lutein, zeaxanthin, β‐cryptoxanthin and β‐carotene were carotenoids in yellow fig varieties. Approximately 80% of carotenoid compounds in yellow fig varieties degraded at the end of drying (i.e. seventh day). L (lightness), a (redness and greenness) and b (yellowness and blueness) colour parameters were measured by Hunter Lab system. Great changes in carotenoid composition and surface colour were observed at ripening stage on tree. A significant reduction in L and b values that refers to browning in figs was made in the first 3 days of drying process.     

Mechanical and dry sliding wear properties of silicon carbide particulate reinforced aluminium–copper alloy matrix composites produced by direct squeeze casting method

In this study, the microstructural features, mechanical properties and dry sliding wear characteristics of Al–4.5Cu–3Mg/15 vol.% SiCp matrix composites, manufactured by squeeze casting technique, were investigated. Wear tests were carried out at 0.5, 1 and 2.0 m/s sliding speeds under the loads of 5, 10, and 15 N for a 1000 m sliding distance versus AISI D2 steel disc. The results showed that, the composites have homogeneously distributed porosity free SiC particles. The failure in composites occurs in both matrix and particles simultaneously implying good bonding between matrix and particles. Friction coefficient of the composites decreased with an increase in the applied load and the sliding speed. In addition, the higher the applied load and the faster the sliding speed are, the higher the wear rate is. SEM analysis indicated that worn surfaces consisted of plastically deformed and oxidized particles removed by the micro-machining effects of the reinforcement phase.     

High Serum Apolipoprotein E Determines Hypertriglyceridemic Dyslipidemias, Coronary Disease and ApoA-I Dysfunctionality

The relevance of serum apolipoprotein E (apoE) levels to two hypertriglyceridemic dyslipidemias has not been clarified. We explored, in a cross-sectional (and short-term prospective) evaluation, the independent relationship of serum apoE to the atherogenic dyslipidemia, hypertriglyceridemia with elevated apoB (HtgB) and to apoA-I dysfunctionality, previously shown in Turkish adults to be independent of apoE genotype. Serum apoE concentrations were measured by immunonephelometry in 1,127 middle-aged adults. In multivariable regression analysis, apoE concentrations showed log-linear associations with apoB and apoA-I levels, waist circumference, independent of C-reactive protein (CRP), homeostatic model assessment (HOMA) index and other confounders. The likelihood of atherogenic dyslipidemia and of HtgB roughly tripled per 1-SD increment in apoE concentrations, additively to apoE genotype, HOMA, apoA-I, CRP concentrations and waist circumference; yet apoA-I, protective against atherogenic dyslipidemia, appeared to promote HtgB, a finding consistent with apoA-I dysfunctionality in this setting. Each 1-SD increment in the apoE level was moreover, associated in both genders with MetS (at OR 1.5), after adjustment for sex, age, apoB, apoA-I and CRP, or for apoE genotypes. Circulating apoE predicted in both genders age-adjusted prevalent and incident coronary heart disease (CHD), independent of apoE genotype and CRP (OR 1.32 [95 % CI 1.11; 1.58]). To conclude, in a general population prone to MetS, elevated apoE concentrations are strongly linked to HtgB and atherogenic dyslipidemia, irrespective of apoE genotype, are associated with MetS and CHD. Excess apoE reflects pro-inflammatory state and likely autoimmune activation.     

Analysis of wind climate and wind energy potential of regions in Turkey

Investments in wind plants have increased rapidly as a result of changes to legal regulations in Turkey over the last five years. This has also led to an increase in the number of wind potential analyses in various regions of the country. This study analyzes the wind climate features of three regions in Turkey and their energy potential. In order to determine the features of wind in these regions, a five-layer Sugeno-type ANFIS model established under the MATLAB-Simulink software was used and the relationship between wind speed and other climate variables determined. In the second phase, WASP software was used to complete the wind energy potential analyses using wind speed data. The final phase includes calculations of the amount of electricity to be obtained technically and capacity usage rates of the installed turbines if wind farms are established in the selected areas. The comparative tables and graphics of the said areas were obtained. In conclusion, the selected areas are well located for the installation of parallel-connected wind plants to the national network in terms of the reliability of wind, the dispersion of wind potential and capacity usage rates.     

Investigation of the molecular changes during chemotherapy in non-Hodgkin''s lymphoma

In addition to the circulating renin-angiotensin system (RAS), a local system has been postulated in the anterior pituitary because immunodetection of its components in various mammalian species. However, different cell types appear to be involved in different species, and there is no general consensus on the subcellular localization of prorenin, renin and angiotensinogen. In this ultrastructural study, we investigated and quantified the presence of these components using double or triple immunogold labeling methods, in all the immunologically identified glandular cell types of the rat anterior pituitary. In contrast to previous reports, all these components were identified not only in lactotropes and gonadotropes but also in somatotropes, corticotropes, and thyrotropes. The highest levels were detected in lactotropes and gonadotropes, and renin gave the greatest signal. Angiotensinogen, prorenin, and renin were co-localized in the secretory granules of all rat pituitary glandular cell types. The simultaneous detection of the substrate (angiotensinogen) and both its specific cleavage enzyme and its proenzyme within the same granule suggests intragranular processing of this component. Moreover, the localization of these three constituents in the secretory granules also suggests that, in the rat anterior pituitary, they follow the regulated secretory pathway.