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11.
Kimmons JE Dewey KG Haque E Chakraborty J Osendarp SJ Brown KH 《Food and nutrition bulletin》2004,25(3):228-238
This study used simple rapid-assessment techniques to test the feasibility of increasing the consumption of complementary foods by infants by asking mothers to increase meal quantity or frequency or by altering the viscosity/energy density of the food. The feasibility of using micronutrient supplements either added directly to food or administered as liquid drops was also examined. The study was conducted in rural Bangladesh and involved four separate short-term behavioral change trials. Depending on the trial, fieldworkers recruited 30 to 45 infants 6 to 12 months of age. Following recommendations to increase the amount of food provided to infants, the mean intakes from single meals increased from 40 +/- 23 g on day 1 to 64 +/- 30 g on day 7 (p < 0.05). In a second trial, the mean meal frequency increased from 2.2 +/- 1.3 on day 1 to 4.1 +/- 1.3 on day 7 (p < 0.05). Provision of high-energy-density diets, prepared by decreasing viscosity with alpha-amylase or by hand-mashing rice and dhal into a paste before feeding, increased single-meal energy consumption from 54 +/- 35 kcal to 79 +/- 52 kcal or 75 +/- 37 kcal (p < 0.05), respectively. Both types of micronutrient supplements were well accepted and used according to recommendations. In conclusion, it was possible to change short-term child-feeding behaviors to promote increased food intake, mealfrequency, energy density, and micronutrient consumption. Because each of these interventions lasted for only about 1 week, however, the long-term sustainability of these changes is not known. Moreover, the effect of increased feeding of complementary foods on intakes of breastmilk and total daily consumption of energy and nutrients requires further study. 相似文献
12.
Saskia Witteborn 《The Journal of communication》2011,61(6):1142-1160
Mobility is one of the defining concepts of globalization processes. For some migrants, however, mobility is restricted by international and national laws as well as sociopolitical discourses, which regulate the migrant body and her ability to create social relations. Based on interviews in asylum seeker accommodations in Germany, this study illustrates how asylum seekers are spatially constructed and arrested through bureaucratic labeling and assignment to heterotopias and as a discursive location of transience and difference. Those processes freeze the forced migrant in place, in social and semiotic spaces, and position it as a politicized discursive location. The positioning is indicative of monitoring the Other as a symbol of threat to the nation in times of risk. Overall, the study illustrates the tensions between transnational mobility and fixity and the intersections between globalization, communication, social, legal, and political practice, and space/place‐making. 相似文献
13.
14.
Dr. Anne Hänchen Dr. Saskia Rausch Benjamin Landmann Dr. Luigi Toti Antje Nusser Prof. Dr. Roderich D. Süssmuth 《Chembiochem : a European journal of chemical biology》2013,14(5):625-632
The antibiotic feglymycin is a linear 13‐mer peptide synthesized by the bacterium Streptomyces sp. DSM 11171. It mainly consists of the nonproteinogenic amino acids 4‐hydroxyphenylglycine and 3,5‐dihydroxyphenylglycine. An alanine scan of feglymycin was performed by solution‐phase peptide synthesis in order to assess the significance of individual amino acid side chains for biological activity. Hence, 13 peptides were synthesized from di‐ and tripeptide building blocks, and subsequently tested for antibacterial activity against Staphylococcus aureus strains. Furthermore we tested the inhibition of peptidoglycan biosynthesis enzymes MurA and MurC, which are inhibited by feglymycin. Whereas the antibacterial activity is significantly based on the three amino acids D ‐Hpg1, L ‐Hpg5, and L ‐Phe12, the inhibitory activity against MurA and MurC depends mainly on L ‐Asp13. The difference in the position dependence for antibacterial activity and enzyme inhibition suggests multiple molecular targets in the modes of action of feglymycin. 相似文献
15.
Leena Maunula Agnieszka Kaupke Petra Vasickova Kirsi Söderberg Iwona Kozyra Sava Lazic Wim H.M. van der Poel Martijn Bouwknegt Saskia Rutjes Kris A. Willems Rita Moloney Martin D'Agostino Ana Maria de Roda Husman Carl-Henrik von Bonsdorff Artur Rzeżutka Ivo Pavlik Tamas Petrovic Nigel Cook 《International journal of food microbiology》2013
In recent years, numerous foodborne outbreaks due to consumption of berry fruit contaminated by human enteric viruses have been reported. This European multinational study investigated possible contamination routes by monitoring the entire food chain for a panel of human and animal enteric viruses. 相似文献
16.
Saskia van Ruth Martin Alewijn Karyne Rogers Elizabeth Newton-Smith Noelia Tena Mirko Bollen Alex Koot 《Food chemistry》2011
Organic production benefits from fair competition and sustained consumer confidence. The latter can only be assured by paper trailing and verification assessments. Traditional analytical strategies for guaranteeing quality and uncovering adulteration have relied on the determination of the amount of a marker compound or compounds in a material and a subsequent comparison of the value(s) obtained with those established for equivalent material. Since it is unlikely to find a unique marker that allows discrimination between organic and conventional produce, selective fingerprinting (profiling) combined with chemometrics is a more promising approach. In this study, carotenoid High Performance Liquid Chromatography–Diode Array Detection profiling combined with k-nearest neighbour classification chemometrics was used to predict the production system (organic vs. non-organic) of chicken eggs. A proof-of-concept set (training set for the model) was composed of eggs from 24 organic farms, 12 free range, and 12 barn farms in the Netherlands. The identities of organic, free range, and barn eggs were predicted with success rates of 100%, 100%, and 84%, respectively. The identity of eggs determined using an additional market test set with eggs from 12 organic, 12 free range, and 12 barn farms originating from the Netherlands and New Zealand resulted in correct classifications for 35 of the 36 samples. The results of this study indicate that this fingerprint approach is a promising tool for analytical verification of the production system of organic eggs. 相似文献
17.
The World Wide Web (WWW) has become the biggest information source for students while solving information problems for school projects. Since anyone can post anything on the WWW, information is often unreliable or incomplete, and it is important to evaluate sources and information before using them. Earlier research has shown that students have difficulties with evaluating sources and information. This study investigates the criteria secondary educational students use while searching the Web for information. 23 students solved two information problems while thinking aloud. After completing the tasks they were interviewed in groups on their use of criteria. Results show that students do not evaluate results, source and information very often. The criteria students mention when asked which criteria are important for evaluating information are not always the same criteria they mention while solving the information problems. They mentioned more criteria but also admitted not always using these criteria while searching the Web. 相似文献
18.
Yuri Yamazaki Kyoko Kohno Dr. Hiroyuki Yasui Prof. Yoshiaki Kiso Prof. Miki Akamatsu Prof. Benjamin Nicholson Dr. Gordafaried Deyanat‐Yazdi Dr. Saskia Neuteboom Dr. Barbara Potts Dr. G. Kenneth Lloyd Dr. Yoshio Hayashi Prof. 《Chembiochem : a European journal of chemical biology》2008,9(18):3074-3081
NPI‐2358 ( 1 ) is a potent antimicrotubule agent that was developed from a natural diketopiperazine, phenylahistin, which is currently in Phase I clinical trials as an anticancer drug. To understand the precise recognition mechanism of tubulin by this agent, we focused on its potent derivative, KPU‐244 ( 2 ), which has been modified with a photoreactive benzophenone structure, and biotin‐tagged KPU‐244 derivatives ( 3 and 4 ), which were designed and synthesized for tubulin photoaffinity labeling. Introduction of the biotin structure at the p′‐position of the benzophenone ring in 2 exhibited reduced, but significant biological activities with tubulin binding, tubulin depolymerization and cytotoxicity in comparison to the parent KPU‐244. Therefore, tubulin photoaffinity labeling studies of biotin‐derivatives 3 and 4 were performed by using Western blotting analysis after photoirradiation with 365 nm UV light. The results indicated that tubulin was covalently labeled by these biotin‐tagged photoprobes. The labeling of compound 4 was competitively inhibited by the addition of diketopiperazine 1 or colchicine, and weakly inhibited by the addition of vinblastine. The results suggest that photoaffinity probe 4 specifically recognizes tubulin at the same binding site as anticancer drug candidate 1 , and this leads to the disruption of microtubules. Probe 4 serves well as a useful chemical probe for potent antimicrotubule diketopiperazines, much like phenylahistin, and it also competes for the colchicine‐binding site. 相似文献
19.
Gas chromatography-olfactometry is a commonly used technique for analysis of odour active compounds. The present study deals with the influence of methodological factors on gas chromatography-olfactometry data, i.e. assessors' qualities and analytical conditions. With respect to the assessors' qualities, the effects of training and fatigue/alertness were studied. Analytical conditions included concentration aspects resulting from varying chromatographic peak shapes and humidified air flow rates at the sniff port. The compounds 2-butanone, diacetyl, ethyl acetate, 3-methyl-1-butanol, ethyl butyrate, hexanal, 2-heptanone and !-pinene were analysed by gas chromatography-olfactometry using the detection frequency and posterior intensity method for collection and processing of the data. Training did not affect the detection of the odour active compounds, but it decreased noise levels considerably. No significant effect of fatigue or decreased alertness was found for the 45-min sessions. The data were influenced by extreme peak shape differences and an intensity optimum was observed for all compounds at a humidified air flow rate of 6 ml min-1. Assessors' qualities and analytical conditions were shown to affect GC-O data and require optimisation for sound gas chromatography-olfactometry analysis. 相似文献
20.
Saskia Sassen 《International Planning Studies》1997,2(2):229-240
Electronic space is often read as a purely technological event, being both self‐contained and neutral. However, this paper argues that what is left out of this purely technological reading is that electronic space is embedded in the larger dynamics organizing society. It has become important to distinguish the Internet, or public spaces, and private electronic space. The financial markets, operating largely through private electronic networks, are a good instance of an alternative form of electronic network power. The paper examines the topography of private electronic space and a new geography of centrality, set within an international context. Emerging cyber‐segmentations are identified which help to conceptualize forms of structuration in electronic space. The paper concludes that electronic space has emerged not simply as a means of transmitting information, but as a major new theatre for capital accumulation and the operations of global capital. Electronic space is now embedded in the larger dynamics organizing society, particularly the economy. 相似文献