Blood oxygen binding in hypoxaemic calves     

Cambier C  Clerbaux T  Detry B  Marville V  Frans A  Gustin P 《Veterinary research》2002,33(3):283-290

Blood oxygen transport and tissue oxygenation were studied in 28 calves from the Belgian White and Blue breed (20 healthy and 8 hypoxaemic ones). Hypoxaemic calves were selected according to their high respiratory frequency and to their low partial oxygen pressure (PaO2) in the arterial blood. Venous and arterial blood samples were collected, and 2,3-diphosphoglycerate, adenosine triphosphate, chloride, inorganic phosphate and hemoglobin concentrations, and pH, PCO, and PO2 were determined. An oxygen equilibrium curve (OEC) was measured in standard conditions, for each animal. The arterial and venous OEC were calculated, taking body temperature, pH and PCO2 values in arterial and venous blood into account. The oxygen exchange fraction (OEF%), corresponding to the degree of blood desaturation between the arterial and the venous compartments, and the amount of oxygen released at the tissue level by 100 mL of blood (OEF Vol%) were calculated from the arterial and venous OEC combined with the PO2 and hemoglobin concentration. In hypoxaemic calves investigated in this study, the hemoglobin oxygen affinity, measured under standard conditions, was not modified. On the contrary, in vivo acidosis and hypercapnia induced a decrease in the hemoglobin oxygen affinity in arterial blood, which combined to the decrease in PaO2 led to a reduced hemoglobin saturation degree in the arterial compartment. However, this did not impair the oxygen exchange fraction (OEF%), since the hemoglobin saturation degree in venous blood was also diminished.  相似文献   

Effects of livestock exclusion on tree regeneration in church forests of Ethiopia     

Alemayehu Wassie  Frank J. Sterck  Demel Teketay  Frans Bongers 《Forest Ecology and Management》2009

In Ethiopia, forests near churches, are the last remnant forest patches. These forests are currently under threat, probably due to diminishing areas of the forest itself and repeated grazing for extended periods by cattle. We assessed the effect of livestock exclusion on the regeneration of four indigenous tree species in two church forests. The four species have a high abundance and socioeconomic value, but limited regeneration in the two forests. We investigated the effect of grazing and trampling on seed germination, seedling survival, and seedling growth. Livestock grazing had a strong negative effect on germination, seedling growth and mortality. In fenced plots, more seeds germinated, seedling survival was higher and seedlings grew faster. Seed germination was higher inside the forest than in the adjacent open area for all species. Seedling survival was not different between forest interior and open fields, except for unfenced plots in the open fields where survival was lower because of the higher grazing pressure. In unfenced plots, no seedlings survived until the end of the year, indicating that grazers destroyed the seedling bank in and around the forest. The significant interaction between fencing and species on seed germination and seedling survival revealed that the magnitude of damage due to grazing can vary with species.  相似文献   

Geographic variation in sexual communication in the cotton bollworm,Helicoverpa armigera     

Ke Gao  Luis M Torres‐Vila  Myron P Zalucki  Yiping Li  Frans Griepink  David G Heckel  Astrid T Groot 《Pest management science》2020,76(11):3596-3605

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Sustainable Low-Volume Analysis of Environmental Samples by Semi-Automated Prioritization of Extracts for Natural Product Research (SeaPEPR)     

Riyanti  Michael Marner  Christoph Hartwig  Maria A. Patras  Stevy I. M. Wodi  Frets J. Rieuwpassa  Frans G. Ijong  Walter Balansa  Till F. Schberle 《Marine drugs》2020,18(12)

The discovery of novel natural products (NPs) that will serve as lead structures has to be an ongoing effort to fill the respective development pipelines. However, identification of NPs, which possess a potential for application in e.g., the pharma or agro sector, must be as cost effective and fast as possible. Furthermore, the amount of sample available for initial testing is usually very limited, not least because of the fact that the impact on the environment, i.e., the sampled biosystem, should be kept minimal. Here, our pipeline SeaPEPR is described, in which a primary bioactivity screening of crude extracts is combined with the analysis of their metabolic fingerprint. This enabled prioritization of samples for subsequent microfractionation and dereplication of the active compounds early in the workflow. As a case study, 76 marine sponge-derived extracts were screened against a microbial screening panel. Thereunder, human pathogenic bacteria (Escherichia coli ATCC35218 and Staphylococcus aureus ATCC33592) and yeast (Candida albicans FH2173), as well as the phytopathogenic fungus Septoria tritici MUCL45407. Overall, nine extracts revealed activity against at least one test organism. Metabolic fingerprinting enabled assigning four active extracts into one metabolic group; therefore, one representative was selected for subsequent microfractionation. Dereplication of the active fractions showed a new dibrominated aplysinopsin and a hypothetical chromazonarol stereoisomer derivative. Furthermore, inhibitory activity against the common plant pest Septoria tritici was discovered for NPs of marine origin.  相似文献   

Iron and zinc deficiencies in China: what is a feasible and cost-effective strategy?   总被引：2，自引：0，他引：2  

Ma G  Jin Y  Li Y  Zhai F  Kok FJ  Jacobsen E  Yang X 《Public health nutrition》2008,11(6):632-638

In order to prioritise interventions for micronutrient deficiencies in China, the populations affected by iron and zinc deficiencies were assessed based on data from the 2002 China National Nutrition and Health Survey. The costs and cost-effectiveness of supplementation, food diversification and food fortification were estimated using the standard World Health Organization ingredients approach. Results indicated that 30% of children (60 years), pregnant and lactating women, and 20% of women of reproductive age were anaemic, some 245 million people. Approximately 100 million people were affected by zinc deficiency (zinc intake inadequacy and stunting), the majority living in rural areas. Among interventions on iron and zinc deficiency, biofortification showed the lowest costs per capita, I 0.01 (international dollars), while dietary diversification through health education represented the highest costs at I 1148(international dollars). The cost-effectiveness of supplementation, food fortification and dietary diversification for iron deficiency alone was I 179(international dollars) , I 66 and I 103 (international dollars) per disability-adjusted life-year (DALY), respectively. Data for biofortification were not available. For zinc deficiency, the corresponding figures were I 399(international dollars), I 153(international dollars) and I 103(international dollars) per DALY, respectively. In conclusion, iron and zinc deficiencies are of great public health concern in China. Of the two long-term intervention strategies, i.e. dietary diversification and biofortification with improved varieties, the latter is especially feasible and cost-effective for rural populations. Supplementation and fortification can be used as short-term strategies for specific groups.  相似文献   

Disentangling women's responses on complex dietary intake patterns from an Indian cross-sectional survey: a latent class analysis     

Padmadas SS  Dias JG  Willekens FJ 《Public health nutrition》2006,9(2):204-211

OBJECTIVE: To investigate the degree of individual heterogeneity related to complex dietary behaviour and to further examine the associations of different dietary compositions with selected characteristics. DESIGN: Latent class analysis was applied to data from the recent cross-sectional National Family Health Survey that collected information on the intake frequency of selected foods. Different responses regarding intake frequency were condensed into a set of five meaningful latent clusters representing different dietary patterns and these clusters were then labelled based on the reported degree of diet mixing. SETTING: Indian states. Subjects In total, 90,180 women aged 15-49 years. RESULTS: Three clusters were predominantly non-vegetarian and two were vegetarian. A very high or high mixed-diet pattern was observed particularly in the southern and a few north-eastern states. Many women in the very high mixed-diet cluster consumed mostly non-green/leafy vegetables on a daily basis, and fruits and other non-vegetarian diet on a weekly basis. In contrast, those in the low mixed-diet cluster consumed more than three-fifths of the major vegetarian diet ingredients alone on a daily basis. The affluent group that represented the low mixed-diet cluster were primarily vegetarians and those who represented the very high mixed-diet cluster were mostly non-vegetarians. The significant interrelationships of different characteristics highlight not only socio-economic, spatial and cultural disparities related to dietary practices, but also the substantial heterogeneity in diet mixing behaviour. CONCLUSIONS: The results of this study confirmed our hypothesis of heterogeneous dietary behaviour of Indian women and yielded useful policy-oriented results which might be difficult to establish otherwise.  相似文献   

Toward harmonization of the European food hygiene/veterinary public health curriculum     

Smulders FJ  Buncic S  Fehlhaber K  Huey RJ  Korkeala H  Prieto M  Steinhauserova I 《Journal of veterinary medical education》2012,39(2):169-179

Prompted by developments in the agri-food industry and associated recent changes in European legislation, the responsibilities of veterinarians professionally active in veterinary public health (VPH), and particularly in food hygiene (FH), have increasingly shifted from the traditional end-product control toward longitudinally integrated safety assurance. This necessitates the restructuring of university training programs to provide starting competence in this area for veterinary graduates or a sub-population of them. To date, there are substantial differences in Europe in the way in which graduate programs in FH/VPH are structured and in the time allocated to this important curricular group of subjects. Having recognized this, the European Association of Establishments for Veterinary Education (EAEVE) recently instituted a working group to analyze the current situation, with a view to produce standard operating procedures allowing fair and transparent evaluations of universities/faculties constituting its membership and in concurrence with explicit European legislation on the professional qualifications deemed necessary for this veterinary discipline. This article summarizes the main conclusions and recommendations of the working group and seeks to contribute to the international efforts to optimize veterinary training in FH/VPH.  相似文献   

Response “Conversion of the Kowa RC‐2 camera to a digital version,instructions for use and postprocessing of the images” by Drs. Dulaurent,Bath & Isard          下载免费PDF全文

Björn Ekesten  Frans Stades  Ingrid Allgoewer  Thomas Dulaurent 《Veterinary ophthalmology》2015,18(4):355-355

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Visualization of dislocation dynamics in colloidal crystals     

Schall P  Cohen I  Weitz DA  Spaepen F 《Science (New York, N.Y.)》2004,305(5692):1944-1948

The dominant mechanism for creating large irreversible strain in atomic crystals is the motion of dislocations, a class of line defects in the crystalline lattice. Here we show that the motion of dislocations can also be observed in strained colloidal crystals, allowing detailed investigation of their topology and propagation. We describe a laser diffraction microscopy setup used to study the growth and structure of misfit dislocations in colloidal crystalline films. Complementary microscopic information at the single-particle level is obtained with a laser scanning confocal microscope. The combination of these two techniques enables us to study dislocations over a range of length scales, allowing us to determine important parameters of misfit dislocations such as critical film thickness, dislocation density, Burgers vector, and lattice resistance to dislocation motion. We identify the observed dislocations as Shockley partials that bound stacking faults of vanishing energy. Remarkably, we find that even on the scale of a few lattice vectors, the dislocation behavior is well described by the continuum approach commonly used to describe dislocations in atomic crystals.  相似文献   

N-dealkylation of atrazine by hydrogenotrophic fluorescent Pseudomonads     

Vincent Vandepitte  Isabella Wierinck  Paul De Vos  Marie -Paule De Poorter  Frans Houwen  Willy Verstraete 《Water, air, and soil pollution》1994,78(3-4):335-341

Two strains of Pseudomonas fluorescens, LMG 10141 and 10140, isolated from soil, cometabolised atrazine in water under hydrogenotrophic conditions. The degradation products were deethylatrazine and deisopropylatrazine while hydroxyatrazine was not detected in cultures of LMG 10141. Labelled experiments indicated that neither the alkyl chains nor the ring structure were completely mineralised.  相似文献