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51.
In order to identify how different additives influenced lipid peroxidation formation, a sausage only using beef juice as pigment source and a standard beef–pork meat sausage were studied. The effects of different additives, including fish oil, myoglobin, nitrite, clove extract, and calcium sources on oxidation and sensory properties were examined. Both sausage systems were stored in 3 different manners prior to testing: (1) frozen immediately at ?80 °C; (2) chilled stored for 2.5 weeks followed by fluorescent light illumination at 4 °C for another 2 wk; (3) frozen at ?20 °C for 5 mo. The frozen group 3 showed the highest peroxide formation and thiobarbituric acid reactive substances (TBARS) for both sausage systems. Unpolar peroxides dominated in both systems. The clove extract could offset the peroxide formation from myoglobin/beef juice and/or fish oil, but the addition of clove flavor was recognized by the sensory panelists. Calcium addition reduced lipid peroxide formation. Added nitrite and fish oil seemed to interact to stimulate nitroso‐myoglobin formation. Nitrite was identified to interact with clove addition and thereby, relatively speaking, increased TBARS. The 2 sausage systems generally ranked the additives similarly as pro– and antioxidants.  相似文献   
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53.
β‐glucans are known for their immune‐modulating properties. However, the heterogeneity of these glucose polymers makes a distinction between the different sources and structures necessary—a fact that has been little allowed for in the literature. We have focused on β‐glucans from cereals as they are already used as functional food ingredients due to their established cholesterol lowering effect. Cereal β‐glucans have shown in vitro activity on cytokine secretion, phagocytic activity and cytotoxicity of isolated immune cells, and activation of the complement system. Animal studies suggest a possible protective effect against an intestinal parasite, against bacterial infection, and a synergistic effect in antibody‐dependent cellular cytotoxicity. Animal studies have shown activity of orally applied cereal β‐glucans indicating uptake or interaction with cells of the gastrointestinal tract. However, uptake is still debated, interaction with intestinal epithelial cells has been suggested but not clarified, and mechanisms of action remain largely unknown. So far, cereal β‐glucans have not shown immune modulation in the few conducted human studies and further studies are needed to clarify their effect.  相似文献   
54.
Combinatorial genetic libraries are powerful tools for diversifying and optimizing biomolecules. The process of library assembly is a major limiting factor for library complexity and quality. Gap repair by homologous recombination in Saccharomyces cerevisiae can facilitate in vivo assembly of DNA fragments sharing short patches of sequence homology, thereby supporting generation of high‐complexity libraries without compromising fidelity. In this study, we have optimized the ordered assembly of three DNA fragments into a gapped vector by in vivo homologous recombination. Assembly is achieved by co‐transformation of the DNA fragments and the gapped vector, using a modified lithium acetate protocol. The optimal gap‐repair efficiency is found at a 1:80 molar ratio of gapped vector to each of the three fragments. We measured gap‐repair efficiency in different genetic backgrounds and observed increased efficiency in mutants carrying a deletion of the SGS1 helicase‐encoding gene. Using our experimental conditions, a gap‐repair efficiency of > 106 plasmid‐harbouring colonies/µg gapped vector DNA is obtained in a single transformation, with a recombination fidelity > 90%. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
55.
A novel synthesis of ferrocene‐modified cellulose, prepared from 6‐azido‐6‐deoxy‐cellulose and ethynylferrocene, is presented. The two components were coupled via copper‐catalyzed click‐type cycloaddition under microwave‐assisted conditions. The surface structure of the cellulose derivative was investigated in comparison with that of pure, microcrystalline cellulose using electron microscopy (scanning, transmission and scanning transmission), showing iron atoms of ferrocene as homogeneously distributed particles. They are detectable as clear signals in the energy‐dispersive X‐ray profile. In addition, Rame‐β‐cyclodextrin was supramolecularly attached to cellulose and the complex formed was studied by use of 2D ROESY NMR and dynamic light scattering. Copyright © 2012 Society of Chemical Industry  相似文献   
56.
High intake of dietary fiber is claimed to protect against development of colorectal cancer. Barley is a rich source of dietary fiber, and possible immunomodulatory effects of barley polysaccharides might explain a potential protective effect. Dietary fiber was isolated by extraction and enzyme treatment. A mixed-linked β-glucan (WSM-TPX, 96.5% β-glucan, Mw 886 kDa), an arabinoxylan (WUM-BS-LA, 96.4% arabinoxylan, Mw 156 kDa), a mixed-linked β-glucan rich fraction containing 10% arabinoxylan (WSM-TP) and an arabinoxylan rich fraction containing 30% mixed-linked β-glucan (WUM-BS) showed no significant effect on IL-8 secretion and proliferation of two intestinal epithelial cell lines, Caco-2 and HT-29, and had no significant effect on the NF-κB activity in the monocytic cell line U937-3κB-LUC. Further enriched arabinoxylan fractions (WUM-BS-LA) from different barley varieties (Tyra, NK96300, SB94897 and CDCGainer) were less active than the mixed-linked β-glucan rich fractions (WSM-TP and WSM-TPX) in the complement-fixing test. The mixed-linked β-glucan rich fraction from NK96300 and CDCGainer showed similar activities as the positive control while mixed-linked β-glucan rich fractions from Tyra and SB94897 were less active. From these results it is concluded that the isolated high molecular weight mixed-linked β-glucans and arabinoxylans from barley show low immunological responses in selected in vitro test systems and thus possible anti-colon cancer effects of barley dietary fiber cannot be explained by our observations.  相似文献   
57.
Thermal breakdown products from four different fire extinguishing agents have been analysed. The agents studied were: bromotrifluoromethane (Halon 1301), pentafluoroethane (HFC 125), heptafluoropropane (HFC 227ea) and dodecafluoro-2-methyl-pentane-3-one (C6F-ketone). In the tests, the studied agent was introduced into a propane flame in a diffusion flame burner. The combustion products were analysed using both conventional IR-techniques and FTIR. It could be concluded that for all four extinguishing agents that the extinguishing agent takes part in the combustion process resulting in production of CO and CO2, which was also confirmed by the increase in smoke production with increasing amounts of agent introduced into the flame. Production of HF and COF2 was found in experiments with all four extinguishing agents. In experiments with Halon 1301, the production of HBr was also determined. It was found that the main fraction of fluorine ends up as HF for HFC 227ea and HFC 125 at lower relative application rates. When approaching extinguishing concentrations, the fraction recovered as COF2 increases, but the total recovery of fluorine, including HF and the remaining part of the fluorine, is found in various organic breakdown products. The recovery of fluorine as HF and COF2 for the C6F-ketone is lower compared to HFC 227ea and HFC 125. There is a clear difference in the recovery of fluorine for Halon 1301 where an almost quantitative recovery as HF or COF2 is found. Halon 1301 additionally contains bromine, which, to a large extent, is recovered as HBr.  相似文献   
58.
Zusammenfassung Eine rote Substanz wurde aus einer tanzanianischen Gelbwurzelprobe (Curcuma Tonga L.) isoliert und durch Röntgen-Einkristall-Analyse als Azofarbstoff Sudanrot G (1-(2-Methoxyphenylazo)-2-naphthol) identifiziert. Die Konzentration des Pigments in der Droge war 0,09%, aus UV-spektroskopischen Daten berechnet.
Sudan Red G as an adulterant in turmeric (Curcuma longa L.)
Summary A red substance was isolated from a Tanzanian sample of turmeric (Curcuma longa L.) and identified by X-ray single crystal analysis as the azo dye Sudan Red G (1-(2-methoxyphenylazo)-2-naphthol). The concentration of the dye in the spice was 0.09%, as calculated from the UV spectrum.
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59.
Reports an error in "Measurement of two social competence aspects in middle childhood" by Ann-Margret Rydell, Berit Hagekull and Gunilla Bohlin (Developmental Psychology, 1997[Sep], Vol 33[5], 824-833). On page 825, Method section, 4th paragraph, line 2, the sentence incorrectly reads, "The county sample consisted of 423 children (M =8 years 5 months, SD =3 years 3 months), constituting 71% of a randomly selected sample of children born in 1986 and living in a county in the middle of Sweden." The correct standard deviation in age in the county sample is 3 months. (The following abstract of the original article appeared in record 1998-00632-009.) The psychometric properties of a rating measure for parents and teachers for social competence, conceptualized as social skills and behaviors, were studied. The rating measure was constructed from factor analyses on 4 samples of school-age children. Factor analyses identified 2 moderately correlated competence aspects, valid for both sexes and for children from varying socioeconomic backgrounds. The first factor, Prosocial Orientation, captured a style promoting positive social interactions; the second factor, Social Initiative, described initiative as opposed to withdrawal in social situations. Scales based on the 2 factors showed reliability in internal consistency and stability across 1 year, validity in interrater agreement concurrently and across 1 year, correspondence with observed peer behavior, and the capacity to discriminate between children of different peer status. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
60.
Inclusionary housing brings together housing supply policies and social housing policies. This article contrasts this combination of policies to a situation where the two policies are kept separate. Drawing on theory of institutional change, the article highlights constitutional, organisational and cultural aspects of inclusionary housing policy and compares this with the features of a policy where inclusionary housing is not adopted. The article seeks to assess similarities and discrepancies between the English version of inclusionary housing and Norway’s housing and planning policy. The planning law and practices, the policy for housing affordability, financial support systems, actors and organisations are assessed and compared. The article concludes that if Norway wanted to implement ICH, it would be possible to customise the planning practices and finance schemes, but new organisations would have to be established. On top of that, there are also cultural divergences between the policy regimes that would need to be regarded.  相似文献   
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