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31.
In recent years, the Internet has become an effective and accessible delivery mechanism for distance education. In 2003, 81% of all institutions of higher education offered at least one fully online or hybrid course. By 2005, the proportion of institutions that listed online education as important to their long-term goals had increased by 8%. This growth in available online courses and their increased convenience and flexibility have stimulated dramatic increases in enrollment in online programs, including the Veterinary Technology Distance Learning Program (VT-DLP) at Purdue University. Regardless of the obvious benefits, distance learning (DL) can be frustrating for the learners if course developers are unable to merge their knowledge about the learners, the process of instructional design, and the appropriate uses of technology and interactivity options into effective course designs. This article describes strategies that we have used to increase students' learning of physiology content in an online environment. While some of these are similar, if not identical, to strategies that might be used in a face-to-face (f2f) environment (e.g., case studies, videos, concept maps), additional strategies (e.g., animations, virtual microscopy) are needed to replace or supplement what might normally occur in a f2f course. We describe how we have addressed students' need for instructional interaction, specifically in the context of two foundational physiology courses that occur early in the VT-DLP. Although the teaching and learning strategies we have used have led to increasingly high levels of interaction, there is an ongoing need to evaluate these strategies to determine their impact on students' learning of physiology content, their development of problem-solving skills, and their retention of information.  相似文献   
32.
The study of the discharge of metallic pollutants into the marine environment through biological material such as sardines makes it possible to evaluate the quality of the biological resources and of the marine environment. The sardine (Sardina pilchardus) is the most popular species for fishing and the most consumed species by the Algiers population. Two toxic metals that can affect human health are studied in this fish. A year of sampling with fishermen was conducted. Sampling was done in the spring, in the autumn, and in April between April 2014 and April 2015. Sampled sardines were grouped by size classes. The gills and muscle were recovered by size classes. The results were explored using a principal components analysis and compared by a Mann-Whitney distribution test. An atomic absorption spectrophotometer was used in the laboratory for analysis. The most important results show that lead levels were higher than those of cadmium in the gills and muscle. For sardines, lead contamination appears to have both gill and food origins. Mann-Whitney comparison tests confirmed this homogeneous distribution of lead between the gills and muscle. The correlation between cadmium in the gills and height or weight is more substantial than that with muscle. The origin of cadmium in sardines is branchial. The food origin appears secondary. From our point of view, the effect of season, i.e., winter (December) and spring (April), favors an increase in metal levels in parallel to the production reserves planned for spawning. The effect of season was observed by use of a biplot. A significant reduction in cadmium and lead content was observed in September. The high temperature, an environmental factor, induced stress that reduced the metal concentrations and the decontamination induced by the issuance of genital products in early summer.  相似文献   
33.
During this study different concentrations of magnesium chloride (MgCl2) were tested on adult wild‐caught sea urchins (Paracentrotus lividus) immediately after their collection in the field in order to assess whether MgCl2 can act as an anaesthetic during their transport and prevent unplanned spawning. Such accidental spawning is a stress response associated with transport of this species. The mortality and gonadal indices were recorded after a 1‐h submersion in different strength solutions of MgCl2 (5, 20, 40, 80 and 100 mmol L−1 MgCl2), followed by 5 h of dry transport under two different temperatures (19 and 25 °C). The effective concentration of MgCl2 was defined as one that does not induce mortality and gonad mass loss following sea urchin transport and laboratory conditioning. Treatment of sea urchins with 5 mmol L−1 MgCl2 prevented mortality and unplanned spawning; however, elevated concentrations of magnesium (40, 80 and 100 mM) were toxic to sea urchins, inducing a massive mortality and gonad mass decrease during the acclimatization period, essentially when sea urchins were transported under an elevated temperature (25 °C). It is concluded that MgCl2 is a suitable non‐toxic anaesthetic, easily available for adult sea urchins (P. lividus) when it is used at its optimal anaesthetizing concentration.  相似文献   
34.
Plant Foods for Human Nutrition - Matcha tea has been used as an adjunct in weight loss programs. The weight loss effects of matcha tea were evaluated in a prospective non-randomized open-label...  相似文献   
35.
True ileal total lysine digestibility was determined and compared with true ileal reactive lysine digestibility when applied to 20 cereal-based breakfast foods. Semisynthetic diets each containing a breakfast cereal as the sole protein source were formulated and fed to growing rats. Titanium dioxide was included as an indigestible marker. Digesta were collected from the rats and total (conventional amino acid analysis) and reactive (guanidination) lysine were determined in both diets and digesta. The true ileal reactive lysine digestibility ranged from 53 to 108% and was significantly higher than the true ileal total lysine digestibility for most of the breakfast cereals. Available lysine content (digestible reactive lysine content) ranged from 0.21 to 3.5 g/kg across the breakfast cereals. The conventional measure of digestible total lysine content significantly overestimated (on average 37%) available lysine for the majority of the cereals. Breakfast cereals undergo a significant degree of lysine modification probably as a result of processing during manufacture.  相似文献   
36.
With the development of the industrial era, environmental pollution by organic and inorganic pollutants increased and became a worldwide issue. Particularly, former industrial sites often present high concentrations of metal(loid)s. These pollutions have adverse effects not only on the environment but also to human health, as pollutants can enter the food chain. Therefore, contaminated sites need rehabilitation. Phytoremediation is a clean and low-cost solution to remediate such sites. However, vegetation establishment can be difficult on such extreme soils from both a physical and a chemical point of view. Consequently, amendments, like biochar and garden soil, must be applied. Biochar, product of biomass pyrolysis under low-oxygen conditions, showed beneficial effects on soil fertility and plant growth, as well as metal(loid) sorption properties. The aims of this study were to investigate the effects of two organic amendments, biochar and garden soil, alone or combined, on the physico-chemical properties of a post-industrial soil and the growth of two Salix species (Salix alba and Salix viminalis) and evaluate the phytostabilizing capacities of the two Salix species. In this goal, a greenhouse experiment was performed, using garden soil at 50% (v/v) and/or biochar at 2 or 5% (w/w). The results showed that biochar did not improve soil physico-chemical properties, neither did it affect plant parameters (dry weight, organ metal(loid)s concentrations). Moreover, higher metal(loid) concentrations were found in the roots compared to the upper parts. Finally, S. alba presented lower metal(loid) concentrations in the aboveground parts compared to S. viminalis, associated with a good growth, which make it a better candidate for phytostabilization of the studied soil.  相似文献   
37.
38.
Strains isolated from chickpea (Cicer arietinum L.) rhizospheric soil from selected sites in Algeria were screened for their plant-growth-promoting potential, for indole acetic acid production and P solubilization ability. Then, we selected native rhizobial strains with high nitrogen-fixing potential. On the basis of their efficiency under controlled conditions, two plant-growth-promoting rhizobacteria (PGPR) isolates and three nodulating bacteria were selected. Then, the effect of single PGPR isolates inoculation was compared to their combination with rhizobial inoculants on plant growth, on native cereal-growing soils under greenhouse conditions. No effects were observed on chickpea yield by using rhizobial inoculation alone, nor by PGPR-rhizobial co-inoculation on two soils presenting weak and no nodulation pattern in natural conditions. Only PGPR inoculation improved growth of plants on soil with no nodulation pattern. These findings emphasized inoculation on native soils at a little scale before large assays on field because no one could predict inocula behavior with native soil microflora.  相似文献   
39.
ABSTRACT: Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent-extracted soybean meal (n = 5) were obtained from People's Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.  相似文献   
40.
Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent- extracted soybean meal (n = 5) were obtained from People’s Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.  相似文献   
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