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111.
Hilal Şahin Ayhan Topuz Monika Pischetsrieder Feramuz Özdemir 《European Food Research and Technology》2009,230(1):155-161
Roasted carob powder was obtained using different time–temperature combinations and some quality characteristics such as total
phenolic content (TPC), total antioxidant activity (TAA), browning index (BI) at 420 nm, UV absorbance (UV-A) at 294 nm, and
pH has been investigated. Both the roasting temperature and time significantly (P < 0.01) affected the quality characteristics of the product. However, the roasting time was found to be a critical factor
in determining the overall quality of the product. While the TPC, TAA, BI and UV-A values of the samples increased with the
increasing roasting temperature and time, the pH of the samples decreased gradually. The quality characteristics of the carob
powders changed markedly in between 20 and 60 min of roasting which indicates that the heat-induced reactions accelerate particularly
in that period of roasting. The correlations between all these chemical properties of carob powder were found to be significant
(P < 0.0001) during roasting. 相似文献
112.
Marta Anna Lech Monika Lekiewicz Kinga Kamiska Zofia Rog Elbieta Lorenc-Koci 《International journal of molecular sciences》2021,22(12)
Growing body of evidence points to dysregulation of redox status in the brain as an important factor in the pathogenesis of schizophrenia. The aim of our study was to evaluate the effects of l-buthionine-(S,R)-sulfoximine (BSO), a glutathione (GSH) synthesis inhibitor, and 1-[2-Bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine dihydrochloride (GBR 12909), a dopamine reuptake inhibitor, given alone or in combination, to Sprague–Dawley pups during early postnatal development (p5–p16), on the time course of the onset of schizophrenia-like behaviors, and on the expression of brain-derived neurotrophic factor (BDNF) mRNA and its protein in the prefrontal cortex (PFC) and hippocampus (HIP) during adulthood. BSO administered alone decreased the levels of BDNF mRNA and its protein both in the PFC and HIP. Treatment with the combination of BSO + GBR 12909 also decreased BDNF mRNA and its protein in the PFC, but in the HIP, only the level of BDNF protein was decreased. Schizophrenia-like behaviors in rats were assessed at three time points of adolescence (p30, p42–p44, p60–p62) and in early adulthood (p90–p92) using the social interaction test, novel object recognition test, and open field test. Social and cognitive deficits first appeared in the middle adolescence stage and continued to occur into adulthood, both in rats treated with BSO alone or with the BSO + GBR 12909 combination. Behavior corresponding to positive symptoms in humans occurred in the middle adolescence period, only in rats treated with BSO + GBR 12909. Only in the latter group, amphetamine exacerbated the existing positive symptoms in adulthood. Our data show that rats receiving the BSO + GBR 12909 combination in the early postnatal life reproduced virtually all symptoms observed in patients with schizophrenia and, therefore, can be considered a valuable neurodevelopmental model of this disease. 相似文献
113.
Barbara Kolsch Prof. Dr. rer. nat. A. Rahmel Monika Schorr 《Materialwissenschaft und Werkstofftechnik》1989,20(11):369-384
Behaviour of gas turbine blade materials under mechanical long term loading and hot gas corrosion. Part 2: Metallographical and microanalytical investigations Results of metallographical and microanalytical investigations on selected specimens after mechanical long term creep and LCF-loading under hot gas corrosion conditions will be presented. Uncoated and MCrAlY or Al-diffusion coated specimens of the polycristalline materials IN-738 LC and IN-939 and the single crystal alloys M 002 mod., CM-SX-6 and B 1914 were investigated. The corrosion attack increases with increasing impurities of the hot gas. Internal nitridation and sulphidation of base material or coating is observed after deterioration of the protective scales rich in Cr2O3 and/or Al2O3. 相似文献
114.
Mittelorientierte Einkristalle verformen sich im Druckversuch über ihre Länge nicht homogen. Es wird ein Rechenverfahren angegeben, in dem diese Inhomogenitäten berücksichtigt werden und Schubspannungs-Abgleitungskurven für den homogen verformten Teil der Probe errechnet werden können. Die Rechnung wird an experimentellen Ergebnissen von Fe—6 Gew.% Si überprüft. 相似文献
115.
Pore bifurcation, growth and pore termination in nanoporous alumina with concave and convex surfaces
The growth of nanoporous alumina on concave or convex aluminium surfaces has been investigated. The number of pores during anodic oxidation increases or decreases almost linearly with the thickness of the oxide which is due to bifurcation or termination of single pores during alumina growth. The anodic oxidation has been constantly conducted in oxalic acid at 40 V. Therefore the average interpore distance has not changed during alumina growth. In earlier papers it has been shown that a bifurcation of pores is the result of the change of voltage and the electrolyte. In this work we have demonstrated that a termination or a bifurcation of pores is also possible by structuring the aluminium to a curved surface with concave or convex properties before oxidation. Those results do not depend on the substrate characteristics or on the alumina preparation techniques. 相似文献
116.
Daniel Franta Lenka Zajíčková Monika Karásková Ondřej Jašek David Nečas Petr Klapetek Miroslav Valtr 《Diamond and Related Materials》2008,17(7-10):1278-1282
Optical properties of the ultrananocrystalline diamond films were studied by multi-sample method based on the combination of variable angle spectroscopic ellipsometry and spectroscopic reflectometry applied in the range 0.6–6.5 eV. The films were deposited by PECVD in a conventional bell jar (ASTeX type) reactor using dual frequency discharge, microwave cavity plasma and radio frequency plasma inducing dc self-bias at a substrate holder. The optical model of the samples included a surface roughness described by the Rayleigh–Rice theory and a refractive index profile in which Drude approximation was used. The results conformed with the present understanding of the polycrystalline diamond growth on the silicon substrate because the existence of silicon carbide and amorphous hydrogenated carbon film between the silicon substrate and nucleation layer was proved. 相似文献
117.
Ohne Zusammenfassung 相似文献
118.
119.
Using the principle of geochemistry of fluoride, green and cost effective anion adsorbents were developed for the removal of F? from water systems. The scheme was further applied for the removal of NO3? also. Carboxymethylated starch functionalized through network formation with acrylamide was used as adsorbent, and the resultant hydrogels were loaded with Fe2+ ions to generate anchorage for the anions. Sorption of Fe2+ was studied as a function of different factors such as time, temperature, pH, and ion strength. The network having the highest Fe2+ uptake was loaded with the Fe2+ ions under optimum conditions and used for the sorption of F? and NO3?. High efficiency has been observed for F?, as even up to 100% uptake has been observed within just 10 minutes. The support shows high selectivity for NO3?, which was used as anion reference. Thermodynamics of sorption confirms low order and low energy processes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
120.
Charu Mathur Melissa H Stigler Cheryl L Perry Monika Arora K Srinath Reddy 《Nicotine & tobacco research》2008,10(1):109-116
This study examined whether the distribution of tobacco use and related psychosocial risk factors among youth in urban India vary by socioeconomic status (SES). Data were derived from a cross-sectional survey of students enrolled in the 6th and 8th grades in 32 schools in Delhi and Chennai (N = 11,642). The survey was conducted in 2004, before the implementation of a program designed to prevent and reduce tobacco use (MYTRI). Mixed-effect regression models were used (a) to determine the prevalence of tobacco use among private (higher SES) and government (lower SES) school students, (b) to investigate whether certain psychosocial factors were associated with increased tobacco use, and (c) to determine how these factors varied by school type. Ever-use of multiple forms of tobacco (e.g., gutkha, bidis, and cigarettes) was more prevalent among government school students than private school students. After adjusting for city, gender, grade, and age, we found the prevalence rate for ever-use of any tobacco product to be 18.9% for government school students, compared with 12.2% for private school students (p<.01). Students in government schools scored lower than private school students on most psychosocial risk factors for tobacco use studied here, indicating higher risk. Government school students scored the lowest for refusal skills, self-efficacy, and reasons not to use tobacco. Social susceptibility to chewing tobacco and social susceptibility to smoking were strong correlates of current tobacco use among government school students. Exposure to tobacco advertising was also a strong correlate of current tobacco use for government school students but not private school students. In two large cities of India, students attending government schools are using many forms of tobacco at higher rates than private school students. The psychosocial risk profile of government school students suggests they are more vulnerable to initiation and use and to outside influences that encourage use. 相似文献