Kepaløg (Allium cepa L) dyrket konventionelt og økologisk - ligheder og forskelle

Denne Grøn Viden giver information om 5 sorters udbytteforskelle v hhv. økologisk og konventionel dyrkning. Desuden dokumenterer den, at der er større frasortering blandt konventionelt dyrkede kepaløg end blandt økologisk dyrkede

Vitamin D depletion aggravates hypertension and target-organ damage

BACKGROUND: We tested the controversial hypothesis that vitamin D depletion aggravates hypertension and target-organ damage by influencing renin. METHODS AND RESULTS: Four-week-old double-transgenic rats (dTGR) with excess angiotensin (Ang) II production due to overexpression of the human renin (hREN) and angiotensinogen (hAGT) genes received vitamin D-depleted (n=18) or standard chow (n=15) for 3 weeks. The depleted group had very low serum 25-hydroxyvitamin D levels (mean+/-SEM; 3.8+/-0.29 versus 40.6+/-1.19 nmol/L) and had higher mean systolic BP at week 5 (158+/-3.5 versus 134.6+/-3.7 mm Hg, P<0.001), week 6 (176.6+/-3.3 versus 162.3+/-3.8 mm Hg, P<0.01), and week 7 (171.6+/-5.1 versus 155.9+/-4.3 mm Hg, P<0.05). Vitamin D depletion led to increased relative heart weights and increased serum creatinine concentrations. Furthermore, the mRNAs of natriuretic peptides, neutrophil gelatinase-associated lipocalin, hREN, and rRen were increased by vitamin D depletion. Regulatory T cells in the spleen and in the circulation were not affected. Ang metabolites, including Ang II and the counter-regulatory breakdown product Ang 1 to 7, were significantly up-regulated in the vitamin D-depleted groups, while ACE-1 and ACE-2 activities were not affected. CONCLUSIONS: Short-term severe vitamin D depletion aggravated hypertension and target-organ damage in dTGR. Our data suggest that even short-term severe vitamin D deficiency may directly promote hypertension and impacts on renin-angiotensin system components that could contribute to target-organ damage. The findings add to the evidence that vitamin D deficiency could also affect human hypertension

Arm-in-cage testing of natural human-derived mosquito repellents

BACKGROUND: Individual human subjects are differentially attractive to mosquitoes and other biting insects. Previous investigations have demonstrated that this can be attributed partly to enhanced production of natural repellent chemicals by those individuals that attract few mosquitoes in the laboratory. The most important compounds in this respect include three aldehydes, octanal, nonanal and decanal, and two ketones, 6-methyl-5-hepten-2-one and geranylacetone [(E)-6,10-dimethylundeca-5,9-dien-2-one]. In olfactometer trials, these compounds interfered with attraction of mosquitoes to a host and consequently show promise as novel mosquito repellents. METHODS: To test whether these chemicals could provide protection against mosquitoes, laboratory repellency trials were carried out to test the chemicals individually at different concentrations and in different mixtures and ratios with three major disease vectors: Anopheles gambiae, Culex quinquefasciatus and Aedes aegypti. RESULTS: Up to 100% repellency was achieved depending on the type of repellent compound tested, the concentration and the relative composition of the mixture. The greatest effect was observed by mixing together two compounds, 6-methyl-5-hepten-2-one and geranylacetone in a 1:1 ratio. This mixture exceeded the repellency of DEET when presented at low concentrations. The repellent effect of this mixture was maintained over several hours. Altering the ratio of these compounds significantly affected the behavioural response of the mosquitoes, providing evidence for the ability of mosquitoes to detect and respond to specific mixtures and ratios of natural repellent compounds that are associated with host location. CONCLUSION: The optimum mixture of 6-methyl-5-hepten-2-one and geranylacetone was a 1:1 ratio and this provided the most effective protection against all species of mosquito tested. With further improvements in formulation, selected blends of these compounds have the potential to be exploited and developed as human-derived novel repellents for personal protection

Mindre sygdom i økologisk dyrkede kepaløg

Sammenlignende forsøg med sorter af kepaløg dyrket økologisk og konventionelt viser væsentligt lavere udbytte i de økologiske løg, i gennemsnit 44% lavere totaludbytte. Det er sansynligvis især problemer omkring etablering der er årsag til det lavere udbytte, bl.a. var plantetallet klart mindst i de økologiske løg, men enkeltløgene var dog også mindre. Samtidig viser resultaterne dog også, at der er mindre sygdom i de økologiske løg, og dermed en lavere frasortering inden salg. Difference i salgbart udbytte (39%) er derfor mindre end ved sammenligning af totaludbytterne

OCTA capillary stall quantification

A method for quantifying the occurrence of transient capillary stalls in OCT angiograms

Supercritical fluid Extraction of PCBs from Lyophilized Fish Tissue

Abstract not availableNA-NOT AVAILABL