6,459 research outputs found
The impact of PL 480 shipments on prices and domestic production of foodgrains in Korea
The main purpose was to evaluate the effect of PL 480 shipments of cereals to Korea on domestic prices and production during the past fourteen years. Secondary data were used for the study with most of data derived from the publications compiled by the various governmental agencies in Korea. PL 480 shipments data were taken from the semiannual and annual reports on Food for Peace published by the House of Repre-sentatives of the United States. An attempt was made to analyze the impact of Public Law 480 gratis assistance to Korea and to identify some quantitative magnitude of effects of the commodities shipped under PL 480 on prices and domestic production of foodgrains. Though the accuracy of data and the performance of the model presented some problems, the results seem to be compatible with the hypothesis; that is, PL 480 imports tend to lower the price of domestically produced grains and lead to a decline in domestic production. However, after taking account of possible price and production dis incentives, the net effect of the imports indicates that there has been a positive contribution to domestic levels of consumption
Oxidoreductase reactions for cosmeceutical production from soy bean products
One of the recent trends in cosmetics industry is using natural and organic ingredients in the manufacturing of cosmetics. Although various plant extracts are major sources of these ingredients, they usually contain complex mixtures with few functionally bioactive ingredients, so that clear scientific proof and supporting data on their effects and efficacy of the ingredients on our body and skin are lacking. Whereas specific biotransformation reactions of single compound can provide various biologically active compounds for their functional studies. Among such biotransformations, we have special interests in producing bioactive natural products(isoflavonoids) derived from soybean such as daidzein and genistein using various oxidoreductases such as P450, tyrosinase, isoflavone reductase and glycoside oxidase, which can control hydroxylation, oxidation/reduction and deglycosylation.
In this talk I will present several examples of producing modified isoflavonoids using such enzymes or enzyme systems, which can be used as cosmeceuticals.
Since most of such oxidoreductase systems require electron transfer system, using recombinant E.coli system, construction of an efficient enzyme systems and protein engineering for their specific activity improvement, cofactor NAD(P)H optimization and related metabolic engineering, enhancing transport of substrate and product, etc. will be applied and discussed using isoflavonoids as model systems. In addition, we would like to explain how “systems and synthetic biological approaches” work for these enzyme reactions, and what kinds of strategies are desirable to develop their industrial scale biotransformations
First-principles investigation of magnetism and electronic structures of substitutional transition-metal impurities in bcc Fe
The magnetic and electronic structures of impurity atoms from Sc to Zn
in ferromagnetic body-centered cubic iron are investigated using the
all-electron full-potential linearized augmented plane-wave method based on the
generalized gradient approximation (GGA). We found that in general, the GGA
results are closer to the experimental values than those of the local spin
density approximation. The calculated formation enthalpy data indicate the
importance of a systematic study on the ternary Fe-C- systems rather than
the binary Fe- systems, in steel design. The lattice parameters are
optimized and the conditions for spin polarization at the impurity sites are
discussed in terms of the local Stoner model. Our calculations, which are
consistent with previous work, imply that the local spin-polarizations at Sc,
Ti, V, Cu, and Zn are induced by the host Fe atoms. The early transition-metal
atoms couple antiferromagnetically, while the late transition-metal atoms
couple ferromagnetically, to the host Fe atoms. The calculated total
magnetization () of bcc Fe is reduced by impurity elements from Sc to Cr as
a result of the antiferromagnetic interaction, with the opposite effect for
solutes which couple ferromagnetically. The changes in are attributed to
nearest neighbor interactions, mostly between the impurity and host atoms. The
atom averaged magnetic moment is shown to follow generally the well-known
Slater-Pauling curve, but our results do not follow the linearity of the
Slater-Pauling curve. We attribute this discrepancy to the weak ferromagnetic
nature of bcc Fe. The calculated Fermi contact hyperfine fields follow the
trend of the local magnetic moments. The effect of spin-orbit coupling is found
not to be significant although it comes into prominence at locations far from
the impurity sites.Comment: 26 pages, 11 figure
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School-Based Telemedicine Interventions for Asthma: A Systematic Review.
BackgroundSchool health systems are increasingly investing in telemedicine platforms to address acute and chronic illnesses. Asthma, the most common chronic illness in childhood, is of particular interest given its high burden on school absenteeism.ObjectiveConduct a systematic review evaluating impact of school-based telemedicine programs on improving asthma-related outcomes.Data sourcesPubMed, Cochrane CENTRAL, CINAHL, ERIC, PsycINFO, Embase, and Google Scholar.Study eligibility criteriaOriginal research, including quasi-experimental studies, without restriction on the type of telemedicine.ParticipantsSchool-aged pediatric patients with asthma and their families.InterventionsSchool-based telemedicine.Study appraisal and synthesis methodsTwo authors independently screened each abstract, conducted full-text review, assessed study quality, and extracted information. A third author resolved disagreements.ResultsOf 371 articles identified, 7 were included for the review. Outcomes of interest were asthma symptom-free days, asthma symptom frequency, quality of life, health care utilization, school absences, and spirometry. Four of 7 studies reported significant increases in symptom-free days and/or decrease in symptom frequency. Five of 6 reported increases in at least one quality-of-life metric, 2 of 7 reported a decrease in at least 1 health care utilization metric, 1 of 3 showed reductions in school absences, and 1 of 2 reported improvements in spirometry measures.LimitationsVariability in intervention designs and outcome measures make comparisons and quantitative analyses across studies difficult. Only 2 of 7 studies were randomized controlled trials.Conclusions and implications of key findingsHigh-quality evidence supporting the use of school-based telemedicine programs to improve patient outcomes is limited. While available evidence suggests benefit, only 2 comparative trials were identified, and the contribution of telemedicine to these studies' results is unclear
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