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31.
Abstract Drying kinetics and quality parameters of potato cubes were evaluated as affected by high pressure processing and hot water blanching. The potato cubes in 1% citric acid solution as immersion medium were pressure treated at 400 MPa for 15 min. Hot water blanching was conducted in boiling water for 3 min. Drying kinetics and quality parameters (i.e., rehydrability, texture, color and apparent density) were assessed for the high pressure–treated and water-blanched samples and for dehydrated and rehydrated samples. Drying rates were found to be higher (p < 0.05) in the initial period of drying for the pressure treated samples. The Page model was found to better fit drying data of the thermally treated samples, and the two-terms model better described the drying behavior of high pressure–treated samples. High pressure–treated samples had a similar rehydrability to thermally treated samples. It was found that pressure–treated samples had a hardness value close to that of fresh samples, whereas thermal treatment resulted in a softer texture. After rehydration, samples of both treatments returned their texture before drying. The total color difference for the thermally blanched samples was higher (p < 0.05) than for pressure–treated samples before drying and after drying. High pressure–treated and dried potato cubes had a color close to that of fresh potato cubes. High pressure–treated and air-dried samples were found to have higher (p < 0.05) apparent density than thermally treated samples. 相似文献
32.
Per Johan Råsmark Čestmír Koňák Petr Štěpánek Christer Elvingson 《Polymer Bulletin》2005,54(4-5):335-342
Summary Dynamic light scattering was used to investigate the dynamics of sodium poly(styrene sulfonate) and fully neutralized poly(acrylic acid) gels as a function of the degree of swelling and weight ratio of cross-linking agent. It was shown that the collective diffusion coefficient increases with increasing degree of swelling and that the diffusion coefficient shows stronger concentration dependence than predicted by scaling arguments. For gel samples measured at the swelling equilibrium, the diffusion coefficient increases with increasing gel concentration for both gel systems. 相似文献
33.
Melinda Szabo Nomi Lajk Karolina Dulka Istvn Szatmri Ferenc Fülp Andrs Mihly Lszl Vcsei Karoly Gulya 《International journal of molecular sciences》2022,23(3)
Kynurenic acid (KYNA) is implicated in antiinflammatory processes in the brain through several cellular and molecular targets, among which microglia-related mechanisms are of paramount importance. In this study, we describe the effects of KYNA and one of its analogs, the brain-penetrable SZR104 (N-(2-(dimethylamino)ethyl)-3-(morpholinomethyl)-4-hydroxyquinoline-2-carboxamide), on the intracellular distribution and methylation patterns of histone H3 in immunochallenged microglia cultures. Microglia-enriched secondary cultures made from newborn rat forebrains were immunochallenged with lipopolysaccharide (LPS). The protein levels of selected inflammatory markers C–X–C motif chemokine ligand 10 (CXCL10) and C–C motif chemokine receptor 1 (CCR1), histone H3, and posttranslational modifications of histone H3 lys methylation sites (H3K9me3 and H3K36me2, marks typically associated with opposite effects on gene expression) were analyzed using quantitative fluorescent immunocytochemistry and western blots in control or LPS-treated cultures with or without KYNA or SZR104. KYNA and SZR104 reduced levels of the inflammatory marker proteins CXCL10 and CCR1 after LPS-treatment. Moreover, KYNA and SZR104 favorably affected histone methylation patterns as H3K9me3 and H3K36me2 immunoreactivities, and histone H3 protein levels returned toward control values after LPS treatment. The cytoplasmic translocation of H3K9me3 from the nucleus indicated inflammatory distress, a process that could be inhibited by KYNA and SZR104. Thus, KYNA signaling and metabolism, and especially brain-penetrable KYNA analogs such as SZR104, could be key targets in the pathway that connects chromatin structure and epigenetic mechanisms with functional consequences that affect neuroinflammation and perhaps neurodegeneration. 相似文献
34.
Antal Péter Nóra Grecsó Gábor Tóth Ferenc Fülöp Wolfgang Lindner István Ilisz 《Israel journal of chemistry》2016,56(11-12):1042-1051
The enantiomeric purity of Nα-Fmoc-protected amino acids is crucial from the viewpoint of peptide synthesis; therefore, a sensitive high-performance liquid chromatographic protocol was developed for the identification and quantification of enantiomeric impurities of commercially available Nα-Fmoc-protected amino acids on Cinchona alkaloid quinine- and quinidine-based weak anion exchanger-type chiral stationary phases. In the course of the evaluation of the chiral chromatographic method, the effect of the mobile phase composition, nature, and concentration of different additives were optimized. The specific phenomenon that quinine- and quinidine-based chiral stationary phases behave as pseudo-enantiomers permits that the sequence of elution of the enantiomers might be reversed by simple column switching. This is quite advantageous as regards the separation of the minor component in the presence of the major one. The method developed permits detection of less than 0.01 % enantiomeric impurity in the presence of the major enantiomer. 相似文献
35.
Alexey Boubnov Andreas Gänzler Sabrina Conrad Maria Casapu Jan-Dierk Grunwaldt 《Topics in Catalysis》2013,56(1-8):333-338
Fresh and mildly aged Pt/Al2O3 model diesel oxidation catalysts with small and large noble metal particle size have been studied during CO oxidation under lean burn reaction conditions to gain more insight into the structure and oscillatory reaction behaviour. The catalytic performance, CO adsorption characteristics using in situ DRIFTS and oxidation state using in situ XAS were correlated. Stable and pronounced oscillations only occurred over the catalyst with smaller particle sizes. Characteristic for this catalyst are low-coordinated surface Pt sites (more corner and edge atoms) which seem to become oxidized at elevated temperature as evidenced by in situ DRIFTS and in situ XAS. In situ XAS further uncovered that the oxidation of the Pt surface starts from the end of the catalyst bed and the oxidation state oscillates like the catalytic activity. 相似文献
36.
Edita Zubrytė Danutė Kaušpėdienė Romas Ragauskas Rima Binkienė Aušra Selskienė 《分离科学与技术》2020,55(16):2855-2868
ABSTRACT A non-hazardous groundwater treatment waste (GWTW) was examined as a low-cost sorbent for Pb(II) and Cu(II) ions. The content of the dominant elements in GWTW was as follows: 78% Fe2O3, 7.4% P2O5, 7.4% CaO and 5.2% SiO2. The removal of Pb(II) and Cu(II) was fast, and more than 67–95% of ions were accumulated by GWTW during the first 3 min. The sorption capacity of GWTW depends on solution pH, concentration and temperature. Equilibrium data fitted well with Langmuir–Freundlich and Langmuir-partition models. The inherently formed nano-adsorbent could be utilized for the treatment of water contaminated with Pb(II) and Cu(II) ions. 相似文献
37.
Multiscale approach to the morphology,structure, and segmental dynamics of complex degradable aliphatic polyurethanes 下载免费PDF全文
Milena Špírková Luďka Machová Libor Kobera Jiří Brus Rafał Poręba Magdalena Serkis Alexander Zhigunov 《应用聚合物科学杂志》2015,132(10)
A multiscale approach spanning from the segmental (subnanometer) up to micrometer level was applied for detailed study of the self‐assembly of aliphatic block polyurethane (PU) elastomers. To understand the principles of the self‐organization of hard and soft segments in the complex multi‐component systems, several two‐component model PU samples, that is, the products of 1,6‐diisocyanatohexane (HDI) with three diols differing in the length and constitution were also prepared, characterized, and investigated: (i) polycarbonate‐based macrodiol (MD), (ii) biodegradable oligomeric diol (DL‐L; product of butane‐1,4‐diol and D,L‐lactide), and (iii) butane‐1,4‐diol (BD). The study (particularly 13C‐1H PILGRIM NMR spectra) reveals complex internal organization and interesting (application appealing) behavior of multi‐component PUs. Hard segments (HDI+BD products) feature self‐assembled and significantly folded chain conformations with interdomain spacing 15–22 nm (small‐angle X‐ray scattering analysis). The small domains are hierarchically assembled in various structural formations of µm size (spherulites) depending on PU composition, as detected by transmission electron microscopy and atomic force microscopy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41590. 相似文献
38.
Ondřej Jankovský Filip Antončík Tomáš Hlásek Vladimír Plecháček David Sedmidubský Štěpán Huber Michal Lojka Vilém Bartůněk 《Journal of the European Ceramic Society》2018,38(6):2541-2546
YBa2Cu3O7-δ (YBCO) is a well-known high-temperature superconductor. However, its critical current density and thus maximum trapped magnetic field can be improved significantly by introducing the secondary phases (artificial pinning centers). In this contribution, we successfully prepared YBCO single-grain bulks with Y2Ba4CuWO10.8 phase serving as a source of pinning centers. This phase was prepared by solid-state reaction and further refined by milling. In the next step single-grain YBCO bulks with homogeneously distributed Y2Ba4CuWO10.8 were prepared by top-seeded melt growth. Precursors as well as the final product were characterized by XRD, SEM and EDS. The phase composition of YBCO bulks containing Y2Ba4CuWO10.8 was analyzed using Rietveld analysis. Thermal stability of YBCO bulk was studied by STA. Furthermore, PPMS was used to study electrical resistivity and critical current density. Bulk superconducting properties such as levitation force and trapped field ability were also measured. 相似文献
39.
ABSTRACT: BACKGROUND: The food group intake patterns of low income Hispanic and African American preschool children are not well documented. The aim of this study was to perform a food group intake analysis of low income minority preschool children and evaluate how macronutrient and micronutrient intake compares to Dietary Reference Intakes (DRI). METHODS: A cross sectional study design using three-day food diaries analyzed by dietary analysis software (Nutrient Database System for Research) was used. Children were recruited from well-child clinics at Children's Healthcare of Atlanta at Hughes Spalding and North Dekalb Grady Satellite Clinic, Atlanta, GA. Low-income, African American and Hispanic preschool age children (n = 291) were enrolled. A total of 105 completed the 3-day food diaries were returned and analyzed. Chi-squared tests were used to assess demographic variables. The mean percentage of intake per day of specific food groups and sub-groups were obtained (servings of given food group/total daily servings). Food intake data and proportion of children meeting DRIs for macro- and micronutrients were stratified by race/ethnicity, nutritional status, and caloric intake, and were compared using t-tests. Regression models controlling for age, BMI and sex were obtained to assess the effect of total caloric intake upon the proportional intake of each studied food group. RESULTS: The mean age of African American children was 2.24 [PLUS-MINUS SIGN] 1.07 years and Hispanic children 2.84 [PLUS-MINUS SIGN] 1.12 years. African Americans consumed more kcal/kg/day than Hispanics (124.7 [PLUS-MINUS SIGN] 51 vs. 96.9 [PLUS-MINUS SIGN] 33, p < 0.05). Hispanics consumed more fruits (22.0 [PLUS-MINUS SIGN] 10.7% vs. 14.7 [PLUS-MINUS SIGN] 13.7%, p < 0.05), while African Americans consumed more grains (25.7 [PLUS-MINUS SIGN] 7.8% vs. 18.1 [PLUS-MINUS SIGN] 6.4%, p < 0.05), meats (20.7 [PLUS-MINUS SIGN] 9.0% vs. 15.4 [PLUS-MINUS SIGN] 6.1%, p < 0.05), fats (9.8 [PLUS-MINUS SIGN] 5.4% vs. 7.0 [PLUS-MINUS SIGN] 5.8%, p < 0.05), sweet drinks (58.7 [PLUS-MINUS SIGN] 17.1% vs. 41.3 [PLUS-MINUS SIGN] 14.8%, p < 0.05) and low-fat dairy products (39.5 [PLUS-MINUS SIGN] 19.3% vs. 28.9 [PLUS-MINUS SIGN] 12.6%, p < 0.05). Among Hispanics, the proportional intake of fruits, fats and grains varied by total caloric intake, while no difference by total caloric intake was found for the dietary patterns of African Americans. Micronutrient intake also differed significantly between African American and Hispanic children. CONCLUSIONS: Food group intake patterns among low-income children differ by ethnic group. There is a need for more research to guide program design and target nutritional interventions for this population. 相似文献
40.
Islam MO Lim YT Chan CE Cazenave-Gassiot A Croxford JL Wenk MR Macary PA Hanson BJ 《International journal of molecular sciences》2012,13(4):4937-4948
The employment of monoclonal antibodies (Mabs) to identify disease-associated biomarkers in clinical samples represents the underlying principle for many diagnostic tests. To date, these have been principally developed for protein targets with few reported applications for lipids due to their hydrophobicity and poor immunogenicity. Oxysterols represent a family of lipids implicated in diverse human diseases where Mab-based detection assays could have a profound effect on their utility as clinical biomarkers. These are usually identified in patients' samples by mass- spectrometry based approaches. Here, we describe an antibody phage-library based screening methodology for generating a recombinant monoclonal antibody (RAb) targeting the oxysterol-15-ketocholestane (15-KA), a lipid implicated in multiple sclerosis and Autoimmune Encephalomyelitis (EAE). The antibody is highly specific for 15-KA and shows little or no binding activity for other closely related oxysterols. We employ RAb2E9 to address the controversy over whether 15-KA is a true biomarker for MS/EAE and show that 15-KA is undetectable in serum taken from mice with EAE using antibody based detection methodologies; a finding confirmed by mass-spectrometry analysis. This study demonstrates the technical feasibility of using phage display to isolate highly specific antibodies against poorly immunogenic, small molecule lipids. 相似文献