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11.
Grain composition of Virginia winter barley and implications for use in feed,food, and biofuels production 总被引:1,自引:0,他引:1
Carl Griffey Wynse Brooks Michael Kurantz Wade Thomason Frank Taylor Don Obert Robert Moreau Rolando Flores Miryeong Sohn Kevin Hicks 《Journal of Cereal Science》2010
Grain compositional components impacting barley (Hordeum vulgare L.) use in food, feed and fuel products, must be combined with improved agronomic traits to produce a commercially viable barley cultivar. Little current information is available on grain composition and variability among winter barley genotypes. This study was conducted to determine the variability among modern hulled and hulless winter barley genotypes in grain composition. Barley types varied significantly in grain and kernel weight, starch, beta-glucan, oil and ash content, but not in protein concentration. Hulless barley had significantly higher grain test weight and starch concentration than hulled and malting types, and significantly higher beta-glucan than malting barley. Hulless barley had significantly lower kernel weights, oil, and ash concentrations than hulled and malting types. Higher starch and lower fiber and ash in grain of hulless barley versus hulled feed or malting type barley are characteristics that increase hulless barley desirability. Selection for high starch concentration among all barley types is feasible and will facilitate development of barley cultivars better suited for use in feed, malt, and ethanol production. 相似文献
12.
Pruning of agroforestry trees, while reducing shade of the crops, usually reduces both biomass production and nitrogen fixation. Short pruning cycles are often not sustainable on the long run, because tree production declines over subsequent pruning cycles. We compared biomass and labile carbohydrate dynamics of Erythrina lanceolata Standley (Papilionaceae) shade trees under total and partial pruning regimes in a vanilla (Vanilla planifolia L.) plantation in South-western Costa Rica. The highest biomass production was measured in the unpruned control, followed by trees with 50% of the leaf pruned every three months, while total pruning every six months resulted in the lowest biomass pruduction. In the more productive treatments, a higher proportion of the production was in branches. Because, the N content of woody branches was high, they were important for nitrogen cycling. In the partial pruning treatment more nitrogen was returned to the soil from litter and woody branches than from pruned leaf. Sugar concentrations were not different between treatments and the dynamics of non-structural carbohydrates (sugar and starch) seems to depend more on plant phenology than pruning treatment. However, the starch concentrations in the total pruning were lower than in the other treatments.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
13.
Wolfe JH Mihalov JD Collard HR McKibbin DD Frank LA Intriligator DS 《Science (New York, N.Y.)》1980,207(4429):403-407
The Ames Research Center Pioneer 11 plasma analyzer experiment provided measurements of the solar wind interaction with Saturn and the character of the plasma environment within Saturn's magnetosphere. It is shown that Saturn has a detached bow shock wave and magnetopause quite similar to those at Earth and Jupiter. The scale size of the interaction region for Saturn is roughly one-third that at Jupiter, but Saturn's magnetosphere is equally responsive to changes in the solar wind dynamic pressure. Saturn's outer magnetosphere is inflated, as evidenced by the observation of large fluxes of corotating plasma. It is postulated that Saturn's magnetosphere may undergo a large expansion when the solar wind pressure is greatly diminished by the presence of Jupiter's extended magnetospheric tail when the two planets are approximately aligned along the same solar radial vector. 相似文献
14.
Lien VANDE MAELE Marc HEYNDRICKX Dominiek MAES Nele DE PAUW Maxime MAHU Marc VERLINDEN Freddy HAESEBROUCK An MARTEL Frank PASMANS Filip BOYEN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):325-328
The antibacterial potential of organic acids and essential oil components against Brachyspirahyodysenteriae, the causative pathogen of swine dysentery, was evaluated. Minimum inhibitoryconcentrations (MIC) of 15 compounds were determined at pH 7.2 and pH 6.0, using a broth microdilution assay.In addition, possible synergism was determined. MIC values for the three tested strains were similar. Fororganic acids, MIC values at pH 6.0 were lower than at pH 7.2. B. hyodysenteriae was mostsensitive to cinnamaldehyde and lauric acid, with MIC values <1.5 mM. Most antibacterial effects of binarycombinations were additive, however, for thymol and carvacrol, synergism could be observed. Invitro results demonstrate the antibacterial action of certain essential oil components and organicacids against B. hyodysenteriae. 相似文献
15.
Frank Havemann Michael Heinz Hildrun Kretschmer 《Journal of Biomedical Discovery and Collaboration》2006,1(1):6
Background
The hypothesis that distance matters but that in recent years geographical proximity has become less important for research collaboration was tested. We have chosen a sample–authors at German immunological institutes–that is relatively homogeneous with regard to research field, language and culture, which beside distance are other possible factors influencing the willingness to co-operate. We analyse yearly distributions of co-authorship links between institutes and compare them with the yearly distributions of distances of all institutes producing papers in journals indexed in the Science Citation Index, editions 1992 till 2002. We weight both types of distributions properly with paper numbers.Results
One interesting result is that place matters but if a researcher has to leave the home town to find a collaborator distance does not matter any longer. This result holds for all years considered, but is statistically most significant in 2002. The tendency to leave the own town for collaborators has slightly increased in the sample. In addition, yearly productivity distributions of institutes have been found to be lognormal.Conclusion
The Internet did not change much the collaboration patterns between German immunological institutes.16.
W. Frank 《Plant foods for human nutrition (Dordrecht, Netherlands)》1977,27(1):37-52
Zusammenfassung Bei den Pesticiden sorgt die Gruppe der Chlorkohlenwasserstoffe wegen ihrer Persistenz immer wieder für neue Probleme. So wird am Beispiel des DDT der momentane Erfolg einerseits und die oft unerwünschte Neben- und Langzeitwirkung andererseits deutlich, weshalb die Industrie heute spezifisch wirksame Verbindungen auf den Markt bringen will, die relativ rasch abgebaut werden. Wenn solche spezifisch wirksame Mittel in zu hoher Konzentration angewandt werden, so treten momentane Gefahren auf, die durch regelmäßige Kontrollen auf ein Mindestmaß reduziert werden können.Bei den Chlorkohlenwasserstoffen haben wir neben der momentanen Gefahr noch die große Gefahr der Langzeitwirkung, die man nur durch Präventivmaßnahmen, gelegentlich auch als Stuttgarter Modell bezeichnet, einschränken kann. Am Beispiel des früher zugelassenen Brassicols wird gezeigt, daß auch Jahre danach der Anbau bestimmter Kulturen stark gefährdet ist, wenn eine starke und nachhaltige Kontamination des Bodens mit Hexachlorbenzol vorliegt. Ähnliches gilt für stark mit Dieldrin kontaminierte Gewächshauserden, deren Ursache die lang zurüchliegende Anwendung aldrinhaltiger Mittel ist. Durch regelmäßige Kontrolle der Böden wird der Grad der Kontamination ermittelt und aufgrund der Erfahrung aus anderen Untersuchungsergebnissen kann dann die bestehende Gefahr durch Anbau entsprechender Kulturen überbrückt werden.Ein wesentliches Kriterium der Überwachung ist es, nicht nur die momentane Gefahr, sondern darüber hinaus auch die mögliche Langzeitgefahr zu erkennen und den Verbraucher davor zu schützen.
Vortrag, gehalten am 30.9.1976 anläßlich der Jahrestagung der Deutschen Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) in Geisenheim/Rheingau. 相似文献
Actual problems of residue control in fruits and vegetables
The pesticides esspecially the chlorinated hydrocarbons always create new problems due to their persistence. The DDT e.g. is the best example for its temporary effectiveness as it shows quite clearly long term side effects. That is the reason that chemical industries today try to produce specific substances which loose those effects quickly. However, if such substances are used without care or precautions e.g. too high a concentration and or without the necessary waiting time, there are temporary dangers. These acute problems can be easily diminished with careful controls.The long term effect of the chlorinated hydrocarbons can be only reduced by preventive controls, sometimes called Stuttgarter Modell.It is desribed, that Brassicol®used years before can cause high contamination of soil and plants. It is also shown, that the soil and some plants can be contaminated with dieldrin years after application of aldrin.First of all the control of soil contamination is necessary. According to the residues of HCB, dieldrin or other chlorinated hydrocarbons the cultivation of certain plants (cress, parsley, carrots, radishes and so on) is at the moment not recommended.It is important, that the official control detects not only the actual danger, more essential is to watch for long term effects and keep it away from people.
Vortrag, gehalten am 30.9.1976 anläßlich der Jahrestagung der Deutschen Gesellschaft für Qualitätsforschung (Pflanzliche Nahrungsmittel) in Geisenheim/Rheingau. 相似文献
17.
Essential regulation of CNS angiogenesis by the orphan G protein-coupled receptor GPR124 总被引:1,自引:0,他引:1
Kuhnert F Mancuso MR Shamloo A Wang HT Choksi V Florek M Su H Fruttiger M Young WL Heilshorn SC Kuo CJ 《Science (New York, N.Y.)》2010,330(6006):985-989
The orphan G protein-coupled receptor (GPCR) GPR124/tumor endothelial marker 5 is highly expressed in central nervous system (CNS) endothelium. Here, we show that complete null or endothelial-specific GPR124 deletion resulted in embryonic lethality from CNS-specific angiogenesis arrest in forebrain and neural tube. Conversely, GPR124 overexpression throughout all adult vascular beds produced CNS-specific hyperproliferative vascular malformations. In vivo, GPR124 functioned cell-autonomously in endothelium to regulate sprouting, migration, and developmental expression of the blood-brain barrier marker Glut1, whereas in vitro, GPR124 mediated Cdc42-dependent directional migration to forebrain-derived, vascular endothelial growth factor-independent cues. Our results demonstrate CNS-specific angiogenesis regulation by an endothelial receptor and illuminate functions of the poorly understood adhesion GPCR subfamily. Further, the functional tropism of GPR124 marks this receptor as a therapeutic target for CNS-related vascular pathologies. 相似文献
18.
Lawrence W. C. Lai K. W. Chau S. K. Wong N. Matsuda Frank T. Lorne 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):289-316
ABSTRACT From a transaction cost perspective, this paper shows how the tradition of consuming marine fish by the majority of Hong Kong's Chinese citizens has shaped the means and modes of marketing seafood in Hong Kong. It is argued that consumer preferences stimulate aquaculture as a non-open access measure to bypass state fish marketing regulations. This has resulted in two outcomes. First, the transaction cost savings on metering output quantity and quality under private property have led not only to the collapse of the state monopoly on marine fish marketing, but also to the emergence of the (then new but) currently popular kind of Chinese seafood restaurant in Hong Kong. Second, consumer preferences for variety have shaped the form of coordination between the producer and the consumer. The advantage of market coordination has led to the emergence of a system of wholesaling and retailing rather than vertical integration. Issues concerning the emergence of Hong Kong as a regional live marine fish production and trading centre are discussed in terms of the contribution of local mariculture to sustainable development. 相似文献
19.
Agnes Agunos Sheryl P. Gow David F. Lger Logan Flockhart Danielle Daignault Andrea Desruisseau Erin Zabek Frank Pollari Richard J. Reid-Smith 《Canadian journal of veterinary research》2021,85(1):27
Eggs are important to the diet of Canadians. This product is one of the supply-managed commodities in Canada, but unlike other commodities, where food safety risks are extensively explored and reported, information on the prevalence of enteric organisms (e.g., Salmonella, Campylobacter) and antimicrobial resistance (AMR) in layers in Canada are limited. This study was conducted to determine the prevalence of select bacteria and the associated AMR patterns in layer flocks using 2 sample matrices. Farms were located within FoodNet Canada and the Canadian Integrated Program for Antimicrobial Resistance Surveillance sentinel sites (SS). Fecal samples (Ontario: ONSS1a, ONSS1b) and environmental sponge swabs (British Columbia: BCSS2a) were collected. Salmonella prevalence was 29% and 8% in ONSS1a and ONSS1b, respectively, and 7% in BCSS2a. S. Kentucky and S. Livingstone were the most frequently isolated serovars and no S. Enteritidis was detected. Campylobacter was not detected in the BC sponge swabs but was isolated from 89% and 53% of Ontario fecal samples (ONSS1a and ONSS1b, respectively). Seven C. jejuni from Ontario were ciprofloxacin-resistant. Escherichia coli prevalence was high in both sample types (98%). Overall, tetracycline resistance among E. coli ranged from 26% to 69%. Resistance to ceftiofur (n = 2 isolates) and gentamicin (n = 2) was relatively low. There were diverse resistance patterns (excludes susceptible isolates) observed among E. coli in Ontario (10 patterns) and British Columbia (14 patterns). This study revealed that fecal samples are more informative for farm-level monitoring of pathogen and AMR prevalence. Without further validation, sponge swabs are limited in their utility for Campylobacter detection and thus, for public health surveillance. 相似文献
20.
Timbermont L Lanckriet A Gholamiandehkordi AR Pasmans F Martel A Haesebrouck F Ducatelle R Van Immerseel F 《Comparative immunology, microbiology and infectious diseases》2009,32(6):503-512
Since the ban on growth-promoting antibiotics in animal feed in the European Union, necrotic enteritis has become a major cause of mortality in broiler chickens. Despite the importance of the disease, the pathogenesis is still not completely understood. In the current study, Clostridium perfringens strains isolated from healthy flocks and isolates from outbreaks of necrotic enteritis were evaluated for the ability to cause gut necrosis in an intestinal loop model in laying hens and in an experimental infection model in broilers. High, intermediate and low alpha toxin producing strains were chosen from each isolation source. Only the isolates from field outbreaks induced necrotic gut lesions, independent of the amount of alpha toxin produced in vitro. It was also shown that alpha toxin producing isolates from calf hemorrhagic enteritis cases were not able to induce necrotic enteritis in poultry. These results suggest the presence of host specific virulence factors in C. perfringens strains, isolated from chickens with intestinal necrotic enteritis lesions. 相似文献