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131.
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In order to develop a new kind of filter that makes a compromise between quasi-optical and more traditional bandpass filtering techniques at millimetre wavelengths, a theoretical modelling of grids in oversize and monomodal waveguides is performed using a variational method.  相似文献   
133.
This study assessed the applicability of the transtheoretical model of behavior change (J. O. Prochaska & C. C. DiClemente, 1983, 1984) to the measurement of contraceptive use among 296 women at high risk for HIV infection and transmission. Structural equation modeling suggested that a measure of general contraceptive use could be used to assess use of oral contraceptives and hormonal implants but that measurement of condom use required separate assessments for main and other partners. Self-efficacy (SE) and decisional balance scales were internally consistent for general contraceptive use, for condom use with main partners, and for condom use with other partners. Consistent with research on other health behaviors, SE scores rose significantly across stages, from precontemplation to maintenance, and a shift in decisional balance was observed for 2 of 3 behaviors. This measurement strategy may enhance the ability to evaluate prevention programs for women at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
134.
Rice is a staple food for a great part of the world’s population, and its processing generates a great volume of low value by-products, such as bran and broken grains. This work aimed to elaborate fermented rice by-products extracts with probiotic strains and with different waxy maize starch (WMS) contents (0%, 4%, 8%, 12% and 16% w/w), in order to select one with texture profile similar to Greek-style yogurt, and to characterise the chemical composition and sensory acceptance of the selected extract added with artificial strawberry aroma and fresh strawberry syrup. The texture profile of the extract changed with WMS content and the 4% WMS fermented rice by-products extract was the most similar to Greek-style yogurt. The flavoured fermented rice by-products with WMS product presented 72.67% moisture, 2.55% protein, 0.2% lipid, 0.8% ash (340 mg 100 g−1 of potassium), 27.4 µmol Trolox g−1 and 134.74 mg GAE 100 g−1 of phenolic compounds. The flavoured fermented rice by-products extract did not show microbiological risk and presented probiotic characteristic. Regarding the sensory analysis, it was observed that the aroma stood out among the other attributes, obtaining the highest score and acceptance index, while colour, flavour and texture scored ‘liked regularly to moderately’. The flavoured fermented rice by-products extract is an innovative product and feasible regarding the technological, physical, chemical, microbiological and sensory characteristics, having great potential to be inserted into the market.  相似文献   
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The enactment of the Water Framework Directive (WFD) in the European Union (EU) triggers intense activity among Member States and raises some criticism. The good status of waters may include an ecological dream that is difficult to achieve. Moreover, criteria for derogations require strong economic arguments. This challenge raises the debate on whether the WFD is part of an incremental process, embedded in prior European water law, with feasible goals, or whether it is a dramatic change of policy towards an ecological dream that emerged during late negotiations, and therefore was hardly achievable. I will state that although the high ecological ambition of the WFD is unprecedented within the EU's water law, it has several precedents in other arenas, notably long enforced in the United States of America. I will argue that the major challenge of the directive is the combination of the ecological dream with an economic ideal, which has no equivalent in the United States.  相似文献   
137.
Different approaches have been reported to enhance penetration of small drugs through physiological barriers; among them is the self-assembly drug conjugates preparation that shows to be a promising approach to improve activity and penetration, as well as to reduce side effects. In recent years, the use of drug-conjugates, usually obtained by covalent coupling of a drug with biocompatible lipid moieties to form nanoparticles, has gained considerable attention. Natural products isolated from plants have been a successful source of potential drug leads with unique structural diversity. In the present work three molecules derived from natural products were employed as lead molecules for the synthesis of self-assembled nanoparticles. The first molecule is the cytotoxic royleanone 7α-acetoxy-6β-hydroxyroyleanone (Roy, 1) that has been isolated from hairy coleus (Plectranthus hadiensis (Forssk.) Schweinf). ex Sprenger leaves in a large amount. This royleanone, its hemisynthetic derivative 7α-acetoxy-6β-hydroxy-12-benzoyloxyroyleanone (12BzRoy, 2) and 6,7-dehydroroyleanone (DHR, 3), isolated from the essential oil of thicket coleus (P. madagascariensis (Pers.) Benth.) were employed in this study. The royleanones were conjugated with squalene (sq), oleic acid (OA), and/or 1-bromododecane (BD) self-assembly inducers. Roy-OA, DHR-sq, and 12BzRoy-sq conjugates were successfully synthesized and characterized. The cytotoxic effect of DHR-sq was previously assessed on three human cell lines: NCI-H460 (IC50 74.0 ± 2.2 µM), NCI-H460/R (IC50 147.3 ± 3.7 µM), and MRC-5 (IC50 127.3 ± 7.3 µM), and in this work Roy-OA NPs was assayed against Vero-E6 cells at different concentrations (0.05, 0.1, and 0.2 mg/mL). The cytotoxicity of DHR-sq NPs was lower when compared with DHR alone in these cell lines: NCI-H460 (IC50 10.3 ± 0.5 µM), NCI-H460/R (IC50 10.6 ± 0.4 µM), and MRC-5 (IC5016.9 ± 0.5 µM). The same results were observed with Roy-OA NPs against Vero-E6 cells as was found to be less cytotoxic than Roy alone in all the concentrations tested. From the obtained DLS results, 12BzRoy-sq assemblies were not in the nano range, although Roy-OA NP assemblies show a promising size (509.33 nm), Pdl (0.249), zeta potential (−46.2 mV), and spherical morphology from SEM. In addition, these NPs had a low release of Roy at physiological pH 7.4 after 24 h. These results suggest the nano assemblies can act as prodrugs for the release of cytotoxic lead molecules.  相似文献   
138.
Peptides obtained by enzymatic hydrolysis of fish proteins exhibit not only nutritional but also biological properties of dietary uses, or even therapeutic potential. The objective of the present study was to isolate and characterize peptides from the protein hydrolysates of barbel muscle with antibacterial activity against Gram-positive (Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, Micrococcus luteus and Bacillus cereus) and Gram-negative (Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa, Klebsiella pneumoniae and Enterobacter sp.) bacteria. Barbel muscle protein hydrolysates (BMPHs), obtained by treatment with Alcalase® (DH = 6.6%), was fractionated by size exclusion chromatography on a Sephadex G-25 and purified by reversed-phase high performance liquid chromatography (RP-HPLC). The molecular masses and amino acid sequences of these peptides were determined using ESI–MS and ESI–MS/MS, respectively. Eleven peptides in FII-1, FII-2, FII-3 and FII-4 sub-fractions separated by RP-HPLC were identified. The most active peptide fraction (FII-3) contained three peptides: Ala–Ala–Ala–Leu; Ala–Ala–Gly–Gly–Val and Ala–Ala–Val–Lys–Met.  相似文献   
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140.
Results examining the effects of tasting profile on dietary intake and health outcomes have varied. This study examined the interaction of sweet liker (SL) and supertaster (ST) (bitter taste test through phenylthiocarbamide [PTC]) status with incidence of metabolic syndrome. Participants (n = 196) as part of baseline testing in a behavioral weight loss study completed measures assessing SL and ST status, metabolic syndrome, and dietary intake. SLs were more likely to be African American. More women than men were STs. There was a significant interaction between ST and SL status as associated with metabolic syndrome, after adjustment for demographic characteristics. This interaction was also significantly associated with fiber and caloric beverage intake. Post hoc analyses showed that participants who were only an ST or SL appeared to have a decreased risk of having metabolic syndrome compared with those who have a combination or are neither taster groups (P = 0.047) and that SL + ST consumed less fiber than SL + non‐ST (P = 0.04). Assessing genetic differences in taster preferences may be a useful strategy in the development of more tailored approaches to dietary interventions to prevent and treat metabolic syndrome. Practical Application : Tasting profile, such as sweet liking (SL) or supertaster (ST), may be influenced by genetics, and therefore in turn, may influence dietary intake. The present study found an interaction between ST and SL status with incidence of metabolic syndrome and fiber and caloric beverage intake. Testing people for these tasting profiles may assist with tailoring dietary recommendations, particularly around fiber and caloric beverage intake, and provide a way to modify metabolic syndrome risk.  相似文献   
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