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101.
This paper reviews the effects that windstorm-induced drastic changes (micro-climate, soil, vegetation, and ground structural heterogeneity) have on forest insect communities. In the current context of shady and CWD-deprived managed forests, windthrow gaps act as regional biodiversity hotspots by maintaining habitat continuity in a mosaic landscape, and by facilitating the breeding and population growth of clearing specialists and saproxylic species. Windthrow gaps are dead-wood islands where forest protection and habitat conservation goals may stand against each other. Besides the quantitative effect of dead wood on bark beetle outbreaks and saproxylic diversity, the latter is favoured by key dead-wood micro-habitats such as large logs, snags and sun-exposed coarse woody debris. The role of natural enemies and sanitation operations in regulating pest outbreaks is discussed. Heterogeneous openings provide many micro-habitats favouring flower-visiting insects, phytophages on saplings, on fallen tree crowns, and on diverse understory flora, as well as ground insects on specific micro-sites. 相似文献
102.
Bouzouidja Ryad Béchet Béatrice Hanzlikova Jitka Sněhota Michal Le Guern Cécile Capiaux Hervé Jean-Soro Liliane Claverie Rémy Joimel Sophie Schwartz Christophe Guénon René Szkordilisz Flora Körmöndi Barnabas Musy Marjorie Cannavo Patrice Lebeau Thierry 《Journal of Soils and Sediments》2021,21(5):1909-1927
Journal of Soils and Sediments - In urban areas, soil functions are deeply impacted by all human activities, e.g., water infiltration, carbon storage, and chemical substances degradation potential.... 相似文献
103.
Kurt Gebruers Johnny Beaugrand Evi Croes Emmie Dornez Christophe M. Courtin Jan A. Delcour 《Cereal Chemistry》2008,85(5):586-590
To date, three different techniques are available for the quantification of TAXI and XIP type proteinaceous xylanase inhibitors in cereals. A first approach is based on the determination of the residual activities of xylanases (also referred to as endo‐1,4‐β‐d ‐xylanases, EC 3.2.1.8), which are specifically inhibited by these inhibitors, after incubation with sample containing the inhibitors. The other two techniques are immunoblotting and ELISA which are based on recognition of TAXI and XIP proteins by specific antibodies. TAXI, as well as XIP, are easily extracted by aqueous buffers. Hence, the large difference in their concentrations (2–10 fold higher for XIP than for TAXI in whole meal) is not caused by differences in extractability. The repeatabilities of the three techniques are comparable. The intra‐assay and inter‐assay coefficients of variation were 6–7 and 10–14%, respectively, which is in the range of values described for methods to quantify other compounds in plant and animal tissues. The three methods give comparable results, suggesting they have similar accuracies. The choice of the technique to be used will depend not only on the sensitivity and dynamic range needed, but also on its technical simplicity and the need for high‐throughput analysis. 相似文献
104.
Alowanou Géorcelin Goué Azando Erick V. B. Adenilé Adam D. Koudandé Delphin O. Chrysostome Christophe A. M. Hounzangbé-Adoté Sylvie M. 《Tropical animal health and production》2020,52(1):309-319
Tropical Animal Health and Production - Gastrointestinal (GI) nematodes remain a major constraint on livestock production throughout the world. This study assessed the in vivo efficacy of the... 相似文献
105.
Petit AN Fontaine F Clément C Vaillant-Gaveau N 《Journal of agricultural and food chemistry》2008,56(15):6761-6767
The aim of this work was to determine the major limitations to photosynthesis induced by the fungicide fludioxonil (fdx) on nontarget grapevines using cutting as a model. The fdx treatments (1.2, 6, and 30 mM) induced a net photosynthetic rate ( P n) decrease without changes in stomatal conductance, suggesting a nonstomatal limitation. Fdx effects on P n were related neither to photosynthetic capacity alteration in leaves nor to loss in PSII activity. The mechanism underlying photosynthesis reduction differed according to the concentration. Fdx at 6 mM led to an increase of light requirement for photosynthesis while 30 mM fdx induced an increase in the respiration rate in the light. P n decrease after 1.2 mM fdx could rather be related to wetness caused by the spraying than to fungicide toxicity. P n recovered 10 days after treatment, meaning that fdx had little deleterious effect on plant physiology or that grapevine has a great capacity to overcome this temporary stress. 相似文献
106.
Xylanase inhibitors bind to nonstarch polysaccharides 总被引:1,自引:0,他引:1
Fierens E Gebruers K Courtin CM Delcour JA 《Journal of agricultural and food chemistry》2008,56(2):564-570
This study is an in-depth investigation of the interaction between polysaccharides and the proteinaceous xylanase inhibitors, Triticum aestivum xylanase inhibitor (TAXI), xylanase inhibitor protein (XIP), and thaumatin-like xylanase inhibitor (TLXI). The binding affinities of all three known types of xylanase inhibitors from wheat are studied by measuring the residual xylanase inhibition activity after incubation of the inhibitors in the presence of different polysaccharides, such as beta-glucans and (arabino)xylans. The binding affinities of all three xylanase inhibitors for (arabino)xylans increased with a decreasing arabinose/xylose ratio (A/X ratio). This phenomenon was observed both with water-extractable and water-unextractable (arabino)xylans. The inhibitors also interacted with different soluble and insoluble beta-glucans. None of the inhibitors tested had the ability to hydrolyze the polysaccharides investigated. The present findings contribute to the unraveling of the function of xylanase inhibitors in nature and to the prediction of the effect of added xylanases in cereal-based biotechnological processes, such as bread making and gluten-starch separation. 相似文献
107.
Rederstorff E Fatimi A Sinquin C Ratiskol J Merceron C Vinatier C Weiss P Colliec-Jouault S 《Marine drugs》2011,9(2):224-241
Polysaccharides are highly heat-sensitive macromolecules, so high temperature treatments are greatly destructive and cause considerable damage, such as a great decrease in both viscosity and molecular weight of the polymer. The technical feasibility of the production of exopolysaccharides by deep-sea bacteria Vibrio diabolicus and Alteromonas infernus was previously demonstrated using a bioproduct manufacturing process. The objective of this study was to determine which sterilization method, other than heat sterilization, was the most appropriate for these marine exopolysaccharides and was in accordance with bioprocess engineering requirements. Chemical sterilization using low-temperature ethylene oxide and a mixture of ionized gases (plasmas) was compared to the sterilization methods using gamma and beta radiations. The changes to both the physical and chemical properties of the sterilized exopolysaccharides were analyzed. The use of ethylene oxide can be recommended for the sterilization of polysaccharides as a weak effect on both rheological and structural properties was observed. This low-temperature gas sterilizing process is very efficient, giving a good Sterility Assurance Level (SAL), and is also well suited to large-scale compound manufacturing in the pharmaceutical industry. 相似文献
108.
Philippot P Van Zuilen M Lepot K Thomazo C Farquhar J Van Kranendonk MJ 《Science (New York, N.Y.)》2007,317(5844):1534-1537
Microscopic sulfides with low 34S/32S ratios in marine sulfate deposits from the 3490-million-year old Dresser Formation, Australia, have been interpreted as evidence for the presence of early sulfate-reducing organisms on Earth. We show that these microscopic sulfides have a mass-independently fractionated sulfur isotopic anomaly (Delta33S) that differs from that of their host sulfate (barite). These microscopic sulfides could not have been produced by sulfate-reducing microbes, nor by abiologic processes that involve reduction of sulfate. Instead, we interpret the combined negative delta34S and positive Delta33S signature of these microscopic sulfides as evidence for the early existence of organisms that disproportionate elemental sulfur. 相似文献
109.
Dornez E Cuyvers S Gebruers K Delcour JA Courtin CM 《Journal of agricultural and food chemistry》2008,56(6):2246-2253
Wheat kernel associated endoxylanases consist of a majority of microbial endoxylanases and a minority of endogenous endoxylanases. At least part of these enzymes can be expected to end up in wheat flour upon milling. In this study, the contribution of both types of these endoxylanases to changes in the arabinoxylan (AX) population during wheat flour breadmaking was assessed. To this end, wheat flour produced from two wheat varieties with different endoxylanase activity levels, both before and after sodium hypochlorite surface treatment of the wheat kernels, was used in a straight dough breadmaking procedure. Monitoring of the AX population during the breadmaking process showed that changes in AX are to a large extent caused by endogenous endoxylanases, whereas the contribution of microbial endoxylanases to these changes was generally very low. The latter points to a limited contamination of wheat flour with microbial enzymes during milling or to an extensive inactivation of these wheat flour associated microbial endoxylanases by endoxylanase inhibitors, present in wheat flour. When all wheat kernel associated microbial endoxylanases were first washed from the kernels and then added to the bread recipe, they drastically affected the AX population, suggesting that they can have a large impact on whole meal breadmaking. 相似文献
110.
Roy C Roque JL François PM Ferrieres A Raboisson D 《Veterinary journal (London, England : 1997)》2012,193(1):274-276
Udder-thigh dermatitis (UTD) is a common disease in dairy cattle. The aim of this study was to define UTD incidence, its risk factors and the involved pathogens. Of 74 respondents, 72 (97%) reported having had the disease. On those farms the incidence was 5.3 cases per 100 cow years. The odds ratio (OR) of UTD in primiparous compared to multiparous cows was 23.4 (95% CI 17.3-33.8). Compared to tied stalls, the ORs of UTD were 0.65 (95% CI 0.45-0.92) and 0.43 (95% CI 0.24-0.71) for free stalls and straw yards, respectively. Udder oedema was reported in 98.3% of cows with UTD. The most common bacteria isolated from affected skin were Fusobacterium spp. (12/14 cases). This study suggests that UTD management should focus on local treatment, reducing udder oedema and increasing exercise. 相似文献