Olive leaf extract as a crosslinking agent for the preparation of electrospun zein fibers

Incorporating active agents, reinforcing structure by crosslinking, thus changing release properties, can be listed as possible modifications in preparation methods of biopolymer fibers. This study introduces oleuropein, major component of olive leaf extract (OLE), as a natural functional crosslinker for electrospun zein fibers, owing to its antioxidant and antimicrobial properties. Incorporation of OLE causes morphological and structural changes indicated by a decrease in fiber diameter up to 27%, an increase in intensity of NH bending region due to interaction with –OH groups and observation of characteristic oleuropein bands. Extract addition also enhances thermal stability. Zein fibers without OLE is fully degraded at 600°C, whereas 10% of OLE loaded zein fibers is left undegraded. Fifty percent of initial phenolic content loaded into fibers is released which indicate the effect of OLE incorporation as accumulation of oleuropein. OLE‐incorporated fibers immersed in PBS are less fused than pure zein fibers, due to the crosslinking effect. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41338.     

Poly(2,6‐di(thiophene‐2‐yl)‐3,5bis(4‐(thiophene‐2‐yl)phenyl)dithieno [3,2‐b;2',3'‐d]thiophene)/carbon nanotube composite for capacitor applications

A novel monomer, 2,6‐di(thiophene‐2‐yl)‐3,5bis(4‐(thiophene‐2‐yl)phenyl)dithieno[3,2‐b;2',3'‐d]thiophene ( Th₄DTT) has been synthesized and used as an electro‐active material. It has been electropolymerized onto glassy carbon (GC) electrode in sodium dodecyl sulfate (SDS) solution (0.1 M) together with multi‐walled carbon nanotubes (MWCNT). A good capacitive characteristics for P(Th₄DTT)/MWCNT composite has been obtained by electrochemical impedance spectroscopy (EIS), which is, to our best knowledge, the first report on capacitor behavior of a dithienothiophene. A synergistic effect has been resolved by Nyquist, Bode‐magnitude—phase and admittance plots. Specific capacitance of the conducting polymer/MWCNT, calculated from cyclic voltammogram (CV) together with area and charge formulas, has been found to be 20.17 F g^?1. Long‐term stability of the capacitor has also been tested by CV, and the results indicated that, after 500 cycles, the specific capacitance is 87.37% of the initial capacitance. An equivalent circuit model of R_s(C₁(R₁(Q(R₂W))))(C₂R₃) has been obtained to fit the experimental and theoretical data. The double layer capacitance (C_dl) value of P(Th₄DTT)/MWCNT (4.43 mF cm^?2) has been found to be 25 times higher than P(Th₄DTT) (C_dl= 0.18 mF cm^?2). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40061.     

Enhanced cholesterol‐ and triglyceride‐ lowering effect of West African green tea

‘The Vert’ is a special type of green tea widely consumed in West Africa and locally associated with many health benefits. However, limited research has been conducted to evaluate its health benefits, such as its enhanced hypolipidemic potential. The objectives of this study were to (1) evaluate the cholesterol‐ and triglyceride‐lowering effects of West African green tea (WAGT) as affected by diet and tea intake, (2) determine the impact of WAGT consumption on the CHD risk ratio, and (3) explore possible mechanisms through which WAGT improves serum lipid profile. Forty‐five male Wistar rats were randomly assigned to one of nine treatment combinations, three diets (regular, high‐cholesterol, and trans‐fat diets) and three fluid sources (no tea, diluted tea, and concentrated tea). After 6 weeks of feeding, animal blood, liver, and feces were harvested. Total cholesterol, HDLc, LDLc, and triglycerides in serum, liver, and feces were determined. The concentrations of bile acids in feces were also measured. WAGT significantly lowered serum and liver cholesterol (30% and 15%, respectively) and increased serum HDL cholesterol (30%). It also reduced liver enlargement caused by storage of excess lipids in high‐cholesterol diet. Overall, the CHD risk ratio was cut by two‐thirds in rats fed high‐cholesterol diet and WAGT. A marked increase in fecal total lipids, cholesterol (60%), and bile acids (50%) was observed in rats that consumed WAGT compared to the control group. These beneficial effects could be attributed to the significantly high flavonoid content of WAGT. Copyright © 2007 Society of Chemical Industry     

Dynamic Multicore Resource Management: A Machine Learning Approach

A machine learning approach to multicore resource management produces self-optimizing on-chip hardware agents capable of learning, planning, and continuously adapting to changing workload demands. This results in more efficient and flexible management of critical hardware resources at runtime.     

Spectroscopic imaging of bone marrow composition in vertebral bodies

The proton spectroscopic imaging technique that uses read gradient during acquisition was used for the measurement of the proton spectra in the lumbar and thoracic part of the spine of a patient with breast cancer without known skeletal métastases. The bone marrow fat water ratios were evaluated in the same location before and after chemotherapy treatment. The results were corrected for relaxation effects. The fat/water ratios showed a significant increase as a consequence of the bone marrow degradation process due to chemotherapy. The proposed spectroscopic imaging technique offers rapid acquisition of proton spectra from large volumes of the vertebral bodies.     

Operational Conditions of Activated Sludge: Influence on Flocculation and Dewaterability

Selected operational conditions of activated sludge are investigated in relation to their effect on flocculation and dewatering. Semi-continuous reactors with 2 -L volume were operated at different mean cell residence times, C/N ratios, and three different influent cations. Results show that MCRT, C/N ratio, and the cation type affect the bioflocculation capacity of activated sludge measured by the quantity of extracellular polymeric substances. As the MCRT value operated in the reactors and the C/N ratio of the influent wastewater increase, total amount of polymers produced increases. High MCRT values and low C/N values cause good dewatering of the sludge. All cations are shown to stimulate the EPS production in a way that the highest total EPS concentrations are observed at the highest cation dosages. The dewaterability of the sludges improves only with increasing calcium and magnesium concentrations and deteriorates with increasing potassium concentration.     

Etiological and clinical patterns of urolithiasis in Turkish children

A beta-glucan binding protein (BGBP) was identified in both white (Penaeus vannamei) and blue shrimp (P. stylirostris) plasma. White shrimp BGBP was purified by affinity chromatography using immobilized laminarin, and its molecular and biological properties were described. White shrimp BGBP is a monomeric protein with a molecular mass of 100 kDa, similar to those described for other crustacean BGBPs. White and blue shrimp BGBPs can be detected with antisera against crayfish BGBP and brown shrimp BGBP. Both amino acid composition and N-terminal sequence are markedly similar to brown shrimp (P. californiensis) and crayfish (Pacifastacus leniusculus) BGBP, indicating that this recognition protein is present in freshwater and marine crustaceans.     

Indoor radon measurements in the granodiorite area of Bergama (Pergamon)-Kozak, Turkey

Indoor radon levels in 20 dwellings of rural areas at the Kozak-Bergama (Pergamon) granodiorite area in Turkey were measured by the alpha track etch integrated method. These dwellings were monitored for eight successive months. Results show that the radon levels varied widely in the area ranging from 11±1 to 727±11 Bq m(-3) and the geometric mean was found to be 63 Bq m(-3) with a geometric standard deviation of 2 Bq m(-3). A log-normal distribution of the radon concentration was obtained for the studied area. Estimated annual effective doses due to the indoor radon ranged from 0.27 to 18.34 mSv y(-1) with a mean value of 1.95 mSv y(-1), which is lower than the effective dose values 3-10 mSv given as the range of action levels recommended by International Commission on Radiation Protection. All dosimetric calculations were performed based on the guidance of the UNSCEAR 2000 report.     

Assessment of natural radioactivity concentrations and gamma dose rate levels in Kayseri, Turkey

This study assesses the level of background radiation for Kayseri province of Turkey. Natural radionuclide activity concentrations in soil samples were determined using high-resolution gamma spectroscopy. Outdoor gamma dose measurements in air at 1 m above ground level were determined using a portable gamma scintillation detector. The obtained results of uranium and thorium series as well as potassium ((40)K) are discussed. The present data were compared with the data obtained from different areas in Turkey. From the measured gamma-ray spectra, the average activity concentrations were determined for (238)U (range from 3.91 to 794.25 Bq kg(-1)), (232)Th (range from 0.68 to 245.55 Bq kg(-1)) and (40)K (range from 23.68 to 2718.71 Bq kg(-1)). The average activity concentrations of (238)U, (232)Th and (40)K were found to be 35.51, 37.27 and 429.66 Bq kg(-1), respectively, and 11.53 Bq kg(-1) for the fission product (137)Cs. The highest values of (238)U, (232)Th and (40)K concentrations (794.25 Bq kg(-1), 245.55 Bq kg(-1), 2718.71 Bq kg(-1), respectively) were observed in abnormal samples at Hayriye village. The average outdoor gamma dose rate in air at 1 m above the ground was determined as 114.43 nGy h(-1). Using the data obtained in this study, the average annual effective dose for a person living in Kayseri was found to be about 140.34 μSv.     

The effect of different surface pretreatments on the bond strength of veneering resin to polyetheretherketone

The aim of this study was to investigate the effect of different surface pretreatment methods on the bond strength of veneering resin to polyetheretherketone (PEEK) based aesthetic frameworks. Five hundred and forty PEEK disks were fabricated and divided into 6 pretreatment groups (n = 90); (C) untreated control group, (B) airborne-particle abrasion, (S) silica coating, (L) etching with Er:YAG (erbium-doped yttrium aluminium garnet) laser, (LB) etching with Er:YAG laser and airborne-particle abrasion and (LS) etching with Er:YAG laser and silica coating. After topographical surface examinations, specimens were conditioned with adhesive and veneering resin was polymerized onto the PEEK specimens. Twenty-four hours after veneering, specimens were subjected to thermal aging. Afterwards, shear bond strength (SBS) tests were performed and the obtained data were analyzed with one-way ANOVA and Tukey test at a significance level of α = .05. Group B (1.58 ± 0.15 μm), Group L (1.79 ± 0.29 μm), Group LB (2.20 ± 0.23 μm) and Group LS (2.31 ± 0.52 μm) demonstrated significantly higher surface roughness (SR) values compared to Group C (1.03 ± 0.11 μm). Group B (10.97 ± 2.88 MPa), Group S (12.07 ± 2.82 MPa), Group LB (12.09 ± 2.08 MPa) and Group LS (13.14 ± 1.45 MPa) demonstrated significantly higher SBS values compared to Group C (6.35 ± 1.21 MPa). Airborne-particle abrasion, silica coating or their combined use with Er:YAG laser system establish durable bond between PEEK and resin; however, only Er:YAG laser treatment has no positive effect on resin-PEEK bond.