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691.
692.
Raphael J. Nawrotzki Kristin Robson Margaret J. Gutilla Lori M. Hunter Wayne Twine Petra Norlund 《Food Security》2014,6(2):283-297
Recurring food crises endanger the livelihoods of millions of households in developing countries around the globe. Owing to the importance of this issue, we explored recent changes in food security between the years 2004 and 2010 in a rural district in Northeastern South Africa. Our study window spans the time of the 2008 global food crisis and allows the investigation of its impacts on rural South African populations. Grounded in the sustainable livelihood framework, we examined differences in food security trajectories among vulnerable sub populations. A unique panel data set of 8,147 households, provided by the Agincourt Health and Demographic Surveillance System (Agincourt HDSS), allowed us to employ a longitudinal multilevel modeling approach to estimate adjusted growth curves for the differential changes in food security across time. We observed an overall improvement in food security that leveled off after 2008, most likely resulting from the global food crisis. In addition, we discovered significant differences in food security trajectories for various sub populations. For example, female-headed households and those living in areas with better access to natural resources differentially improved their food security situation, compared to male-headed households and those households with lower levels of natural resource access. However, former Mozambican refugees witnessed a decline in food security. Therefore, poverty alleviation programs for the Agincourt region should work to improve the food security of vulnerable households, such as former Mozambican refugees. 相似文献
693.
Kristin Topp Hajo Haase Christoph Degen Gerhard Illing Boris Mahltig 《Journal of Coatings Technology and Research》2014,11(6):943-957
Effect pigments were originally developed to realize advanced optical effects by coating on several types of material surfaces. However, metallic effect pigments are expected to be valuable for many other applications, such as antimicrobial effects, electrical conductive coatings, or shielding against radio waves (electromagnetic shielding). Accordingly, the aim of this article is to evaluate the advanced properties which can be realized by application of coatings containing metallic effect pigments onto textile materials leading to new functional textiles. In total, four different metallic effect pigments were investigated and compared to silver and graphite pigments. By application of coatings with copper- or silver-containing effect pigments significant antibacterial properties against E. coli and S. aureus can be realized. To achieve electric conductive textiles, which also enable effective shielding against radio waves, a copper pigment carrying a silver coating leads to the best properties. Altogether, an effective coating method is presented to achieve functional textiles that offer a broad range of possible applications. 相似文献
694.
Ke Ma Li Qiu Kristin Mrasek Jun Zhang Thomas Liehr Luciana Gon?alves Quintana Zheng Li 《International journal of molecular sciences》2012,13(9):11974-11999
Genomic instability, a hallmark of cancer, occurs preferentially at specific genomic regions known as common fragile sites (CFSs). CFSs are evolutionarily conserved and late replicating regions with AT-rich sequences, and CFS instability is correlated with cancer. In the last decade, much progress has been made toward understanding the mechanisms of chromosomal instability at CFSs. However, despite tremendous efforts, identifying a cancer-associated CFS gene (CACG) remains a challenge and little is known about the function of CACGs at most CFS loci. Recent studies of FATS (for Fragile-site Associated Tumor Suppressor), a new CACG at FRA10F, reveal an active role of this CACG in regulating DNA damage checkpoints and suppressing tumorigenesis. The identification of FATS may inspire more discoveries of other uncharacterized CACGs. Further elucidation of the biological functions and clinical significance of CACGs may be exploited for cancer biomarkers and therapeutic benefits. 相似文献
695.
A method for sampling and electrophoretic analysis of aqueous plugs segmented in a stream of immiscible oil is described. In the method, an aqueous buffer and oil stream flow parallel to each other to form a stable virtual wall in a microfabricated K-shaped fluidic element. As aqueous sample plugs in the oil stream make contact with the virtual wall, coalescence occurs and sample is electrokinetically transferred to the aqueous stream. Using this virtual wall, two methods of injection for channel electrophoresis were developed. In the first, discrete sample zones flow past the inlet of an electrophoresis channel and a portion is injected by electroosmotic flow, termed the "discrete injector". With this approach at least 800 plugs could be injected without interruption from a continuous segmented stream with 5.1% RSD in peak area. This method generated up to 1,050 theoretical plates, although analysis of the injector suggested that improvements may be possible. In a second method, aqueous plugs are sampled in a way that allows them to form a continuous stream that is directed to a microfluidic cross-style injector, termed the "desegmenting injector". This method does not analyze each individual plug but instead allows periodic sampling of a high-frequency stream of plugs. Using this system at least 1000 injections could be performed sequentially with 5.8% RSD in peak area and 53,500 theoretical plates. This method was demonstrated to be useful for monitoring concentration changes from a sampling device with 10 s temporal resolution. Aqueous plugs in segmented flows have been applied to many different chemical manipulations including synthesis, assays, sampling processing and sampling. Nearly all such studies have used optical methods to analyze plug contents. This method offers a new way to analyze such samples and should enable new applications of segmented flow systems. 相似文献
696.
Lothar W. Meyer Kristin Sommer Thorsten Halle Matthias Hockauf 《Journal of Materials Science》2008,43(23-24):7426-7431
Crack growth behaviour of ultrafine-grained AA6063, processed by equal-channel angular pressing (ECAP) via route E at room temperature, was evaluated with special emphasis on the effect of grain size distribution and work hardening. A bimodal, two times ECAPed condition and a monomodal ultrafine-grained condition after eight ECAP passes are compared with the coarse grained peak aged material. Depending on their microstructure, the ECAPed materials show significantly lower fatigue threshold values (ΔK th) and higher crack growth rates (da/dN) than their coarse grained counterparts. Micrographs of the crack propagation surfaces reveal the reduced grain size as major key to increased crack growth rates of the ECAPed material, as it influences roughness-induced crack closure and crack deflections. Furthermore, the effects of other features, such as ductility, work hardening capability and grain boundary characteristics, are discussed. 相似文献
697.
Pagoto Sherry; Bodenlos Jamie S.; Schneider Kristin L.; Olendzki Barbara; Spates C. Richard; Ma Yunsheng 《Canadian Metallurgical Quarterly》2008,45(3):410
More than one-third of treatment-seeking obese patients are clinically depressed. No evidence-based treatments exist for individuals with comorbid depression and obesity. Behavioral activation (BA), an effective treatment for depression, might also facilitate weight loss. The objective of this study is to evaluate the feasibility and efficacy of BA plus nutrition counseling for weight loss among individuals with comorbid major depressive disorder (MDD) and obesity. The BA intervention targeted both weight reduction and depression in 14 obese patients (79% female; 86% Caucasian) who met criteria for MDD. At baseline, mean Beck Depression Inventory (BDI-II) score was 26.71, and mean Hamilton Depression Rating Scale (HDRS) score was 16.00. Significant reductions at 12-weeks in both BDI-II and HDRS were observed with 10 participants reaching full remission at post treatment. Reductions in body weight, daily caloric intake, and physical activity were observed. BA with nutrition counseling appears to have potential as a weight loss treatment in the context of depression. Results support the need for a randomized controlled trial to evaluate the efficacy of BA for both weight loss and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
698.
Kristin R. Carpenter Chris R. Killmore Rian Dippenaar 《Metallurgical and Materials Transactions B》2014,45(2):372-380
Hot ductility tests were used to determine the hot-cracking susceptibility of two low-carbon, low Mn/S ratio steels and compared with a higher-carbon plain C-Mn steel and a low C, high Mn/S ratio steel. Specimens were solution treated at 1623 K (1350 °C) or in situ melted before cooling at 100 K/min to various testing temperatures and strained at 7.5 × 10?4 s?1, using a Gleeble 3500 Thermomechanical Simulator. The low C, low Mn/S steels showed embrittlement from 1073 K to 1323 K (800 °C to 1050 °C) because of precipitation of MnS at the austenite grain boundaries combined with large grain size. Isothermal holding for 10 minutes at 1273 K (1000 °C) coarsened the MnS leading to significant improvement in hot ductility. The higher-carbon plain C-Mn steel only displayed a narrow trough less than the Ae3 temperature because of intergranular failure occurring along thin films of ferrite at prior austenite boundaries. The low C, high Mn/S steel had improved ductility for solution treatment conditions over that of in situ melt conditions because of the grain-refining influence of Ti. The higher Mn/S ratio steel yielded significantly better ductility than the low Mn/S ratio steels. The low hot ductility of the two low Mn/S grades was in disagreement with commercial findings where no cracking susceptibility has been reported. This discrepancy was due to the oversimplification of the thermal history of the hot ductility testing in comparison with commercial production leading to a marked difference in precipitation behavior, whereas laboratory conditions promoted fine sulfide precipitation along the austenite grain boundaries and hence, low ductility. 相似文献
699.
700.
Effect of acetylation,oxidation and annealing on physicochemical properties of bean starch 总被引:3,自引:0,他引:3
Black and Pinto bean starches were physically and chemically modified to investigate the effect of modification on digestibility and physicochemical properties of bean starch. The impact of acetylation, oxidation (ozonation) and annealing on the chemical composition, syneresis, swelling volume, pasting, thermal properties and digestibility of starches was evaluated. The physicochemical and estimated glycemic index (eGI) of the Black and Pinto bean starches treated with ozone were not significantly (P > 0.05) different than that of their respective control starches. Annealed starches had improved thermal and pasting properties compared to native starches. Acetylated starches presented reduced syneresis, good pasting properties and lower eGI. Also, all modified starches had increased levels of resistant starch (RS). Therefore, the digestibility and physicochemical properties of bean starch were affected by the type of modification but there were no significant (P > 0.05) differences between the Black and Pinto bean starches. 相似文献