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31.
Maintaining the numbers of wood mice and common voles at an acceptable economic level, especially during years of massive outbreaks, is a major challenge in plant protection. Efforts to reduce the negative effects of rodenticides on the environment, to improve the integrated pest control system, and to minimize risks for human and animal health require investigation of the potentials of cellulose, as a natural product, and sodium selenite as rodenticides. The present study was conducted to determine the sensitivity of these rodent species to bromadiolone (a.i. 0.005 %), sodium selenite (a.i. 0.1 and 0.05 %), and cellulose (a.i. 45 %) baits. All experiments were done using no-choice and choice feeding trials. A low acceptance of cellulose baits was found in the choice feeding trial, and the time of first deaths indicate that stress and hunger increase the death rate in both species. The taste had a negative impact on the acceptability of baits containing sodium selenite. Low bait acceptance of cellulose and sodium selenite resulted in lower mortality of both species. The acquired results indicate that bromadiolone remains a more effective solution than cellulose and sodium selenite for control of wood mice and common voles.  相似文献   
32.
Intracellular pathogens such as Listeria monocytogenes subvert cellular functions through the interaction of bacterial effectors with host components. Here we found that a secreted listerial virulence factor, LntA, could target the chromatin repressor BAHD1 in the host cell nucleus to activate interferon (IFN)-stimulated genes (ISGs). IFN-λ expression was induced in response to infection of epithelial cells with bacteria lacking LntA; however, the BAHD1-chromatin associated complex repressed downstream ISGs. In contrast, in cells infected with lntA-expressing bacteria, LntA prevented BAHD1 recruitment to ISGs and stimulated their expression. Murine listeriosis decreased in BAHD1(+/-) mice or when lntA was constitutively expressed. Thus, the LntA-BAHD1 interplay may modulate IFN-λ-mediated immune response to control bacterial colonization of the host.  相似文献   
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Critical point relascope sampling is developed and shown tobe design-unbiased for the estimation of log volume when usedwith point relascope sampling for downed coarse woody debris.The method is closely related to critical height sampling forstanding trees when trees are first sampled with a wedge prism.Three alternative protocols for determining the critical samplingpoints on a log are presented and simulations are employed tosuggest the most efficient protocol to use in practice.  相似文献   
35.
The performance of 25 provenances in international trials on seven sites in four countries was assessed for survival and growth at 3 years. Of these provenances, seven were from Queensland, 12 from Northern Territory, Australia, and six from Papua New Guinea. Significant growth differences were found: (a) among provenances at four sites, (b) among the sites, and (c) between provenance regions. The interaction between sites and provenances as well as between sites and provenance regions was also significant. The poorest growth was recorded in Kanchanaburi, Thailand, while the best growth was in Banjarbaru, Indonesia. Stability analyses of the provenance x site interaction revealed eight provenances with high vigour and good tree form that were relatively stable across sites. These included Archer River, South Coen, Coen River and Wenlock River provenances from Queensland; Noogoo Swamp and Mann River provenances from Northern Territory; and North Bensbach and Old Tonda Village provenances from Papua New Guinea.  相似文献   
36.
This review is prefaced by an introduction to biological characteristics of Imperata cylindrica which relate to its control by chemical and mechanical methods. Of the many herbicides tested and used against I. cylindrica, glyphosate has became the market leader but the potential of imazapyr is also recognized. The activity of additives to improve glyphosate and imazapyr performance is summarised and linked to a review of spray volume rates and the use of three types of application equipment: hydraulic (knapsack) sprayers, spinning discs and weed wipers. An example of the practical use of glyphosate in an estate crop is given. The role of tillage in the management of I. cylindrica is discussed but emphasis is given to pressing as a technique for promoting natural regeneration of forestry species. An integrated approach is considered to be essential for the management of I. cylindrica whereby fire prevention and methods of control are deployed in the conversion of Imperata-dominated land into sustainable, productive systems. Examples are given of integrated management in commodity plantations, rehabilitation of Imperata grasslands through reforestation, and conservation tillage to sustain soil fertility and productivity.  相似文献   
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The purpose of this study was to create water-in-oil (W/O) and water-in-oil-in-water (W/O/W) emulsions containing gelled internal water droplets. Twenty weight percent W/O emulsions stabilized by a nonionic surfactant (6.4 wt % polyglycerol polyricinoleate, PGPR) were prepared that contained either 0 or 15 wt % whey protein isolate (WPI) in the aqueous phase, with the WPI-containing emulsions being either unheated or heated (80 degrees C for 20 min) to gel the protein. Optical microscopy and sedimentation tests did not indicate any significant changes in droplet characteristics of the W/O emulsions depending on WPI content (0 or 15%), shearing (0-7 min at constant shear), thermal processing (30-90 degrees C for 30 min), or storage at room temperature (up to 3 weeks). W/O/W emulsions were produced by homogenizing the W/O emulsions with an aqueous Tween 20 solution using either a membrane homogenizer (MH) or a high-pressure valve homogenizer (HPVH). For the MH the mean oil droplet size decreased with increasing number of passes, whereas for the HPVH it decreased with increasing number of passes and increasing homogenization pressure. The HPVH produced smaller droplets than the MH, but the MH produced a narrower particle size distribution. All W/O/W emulsions had a high retention of water droplets (>95%) within the larger oil droplets after homogenization. This study shows that W/O/W emulsions containing oil droplets with gelled water droplets inside can be produced by using MH or HPVH.  相似文献   
39.
Hawthorn [Crataegus monogyna Jacq. and Crataegus oxyacantha L.; sin. Crataegus laevigata (Poiret) DC., Rosaceae] leaves, flowers, and berries are used in traditional medicine in the treatment of chronic heart failure, high blood pressure, arrhythmia, and various digestive ailments, as well as geriatric and antiarteriosclerosis remedies. According to European Pharmacopoeia 6.0, hawthorn berries consist of the dried false fruits of these two species or their mixture. The present study was carried out to test free-radical-scavenging, anti-inflammatory, gastroprotective, and antimicrobial activities of hawthorn berries ethanol extract. Phenolic compounds represented 3.54%, expressed as gallic acid equivalents. Determination of total flavonoid aglycones content yielded 0.18%. The percentage of hyperoside, as the main flavonol component, was 0.14%. With respect to procyanidins content, the obtained value was 0.44%. DPPH radical-scavenging capacity of the extract was concentration-dependent, with EC50 value of 52.04 microg/mL (calculation based on the total phenolic compounds content in the extract). Oral administration of investigated extract caused dose-dependent anti-inflammatory effect in a model of carrageenan-induced rat paw edema. The obtained anti-inflammatory effect was 20.8, 23.0, and 36.3% for the extract doses of 50, 100, and 200 mg/kg, respectively. In comparison to indomethacin, given in a dose producing 50% reduction of rat paw edema, the extract given in the highest tested dose (200 mg/kg) showed 72.4% of its activity. Gastroprotective activity of the extract was investigated using an ethanol-induced acute stress ulcer in rats with ranitidine as a reference drug. Hawthorn extract produced dose-dependent gastroprotective activity (3.8 +/- 2.1, 1.9 +/- 1.7, and 0.7 +/- 0.5 for doses of 50, 100, and 200 mg/kg, respectively), with the efficacy comparable to that of the reference drug. Antimicrobial testing of the extract revealed its moderate bactericidal activity, especially against gram-positive bacteria Micrococcus flavus, Bacillus subtilis, and Lysteria monocytogenes, with no effect on Candida albicans. All active components identified in the extract might be responsible for activities observed.  相似文献   
40.
Water, Air, & Soil Pollution - The relative contribution of the main mechanisms that control indoor air quality in residential flats was examined. Indoor and outdoor concentration measurements...  相似文献   
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