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71.
This paper reports on an antimicrobial finishing for polyamide with high washfastness. As antimicrobial agent modified silica sols containing silver components are used as coating agent and are applied to the polyamide fabric by using a semi-industrial procedure. The antimicrobial properties of coated polyamide fabrics are determined against the bacteria E. coli. Significant antimicrobial effects are observed even after 40 washing cycles. The amount of silver on the polyamide fabrics was measured by using ICP-OES. Besides this, samples are investigated by means of UV/Vis-spectroscopy and scanning electron microscopy. Furthermore textile properties as, e.g., air permeability and mechanical properties were measured. Due to high antimicrobial effect and the strong washfastness of this finishing, this reported method could be of high interest for industrial production processes. 相似文献
72.
73.
Key message
The concept of expected losses is an appropriate measure for integrating risk in the determination of the optimal rotation period and choice of tree species.Context
Natural threats are challenging forest management decisions. Essential decisions about the optimal length of a harvest period are often taken without considering risks.Aims
Here, a practical and easy to apply way to integrate risk in these decisions is shown. Furthermore, it is seen how the rotation period changes according to the risk-type and risk-level.Methods
The marginal principle of Preßler’s indicator rate is developed further by including the concept of expected losses, leading to an optimal harvest age under risk. The application of the new formula is shown by a simulation, which also visualises the influence on the optimal rotation age.Results
Whether risk influences the optimal harvest age compared to a risk free solution, depends on the relationship between expected losses in terms of land rent of the succeeding stand and expected losses in terms of value growth of the existing stand. If they are equal, the rotation age stays. If the expected loss on value growth is bigger than on land rent, the rotation period will be shorter, while it will be longer if the relation is inverse.Conclusion
The concept of expected losses can be applied to practically determine the optimal rotation period under risk.74.
Raessler M Wissuwa B Breul A Unger W Grimm T 《Journal of agricultural and food chemistry》2008,56(17):7649-7654
The exact and reliable determination of carbohydrates in plant samples of different origin is of great importance with respect to plant physiology. Additionally, the identification and quantification of carbohydrates are necessary for the evaluation of the impact of these compounds on the biogeochemistry of carbon. To attain this goal, it is necessary to analyze a great number of samples with both high sensitivity and selectivity within a limited time frame. This paper presents a rugged and easy method that allows the isocratic chromatographic determination of 12 carbohydrates and sugar alcohols from one sample within 30 min. The method was successfully applied to a variety of plant materials with particular emphasis on perennial ryegrass samples of the species Lolium perenne. The method was easily extended to the analysis of the polysaccharide inulin after its acidic hydrolysis into the corresponding monomers without the need for substantial change of chromatographic conditions or even the use of enzymes. It therefore offers a fundamental advantage for the analysis of the complex mixture of nonstructural carbohydrates often found in plant samples. 相似文献
75.
Ann Van Herzele Eva M. De Clercq Torsten Wiedemann 《Urban Forestry & Urban Greening》2005,3(3-4):177-188
Current strategies for creating new woodlands in the urban periphery aim to provide as many people as possible with a recreational green space close to where they live. When taking a socially inclusive approach, however, this also involves a number of ‘distributional’ questions. These refer to the kind of people likely to benefit the most from such a plan: urban or suburban residents, low or high-income groups, and so forth. This article presents a GIS-based working method aimed at exploring different options for urban woodland proposals with regard to their positioning in relation to residential areas, as well as the socio-spatial characteristics of those areas. The example of seven possible locations for a new ‘peri-urban forest’ in Antwerp, Belgium was used to demonstrate the method's potential to address relevant questions in socially inclusive planning and hence, to improve strategic planning for new urban woodlands. 相似文献
76.
Anna-Lena Berg Dolores Gavier-Widén Kristina Nilsson Frederik Widén Mikael Berg Sune Gregorius Erik Agren Maria Erlandsson Torsten M?rner 《Journal of veterinary diagnostic investigation》2007,19(1):113-117
A neurologic disease affected a colony of endangered Fennoscandian arctic foxes (Alopex lagopus) kept in captivity for breeding purposes. Several outbreaks of disease occurred between 1994 and 2004. The clinical signs included ataxia, indications of anosmia, blindness, and abnormal behavior. The disease was characterized by severe necrotizing encephalitis affecting mostly the cranial cerebrum, basal ganglia, and olfactory bulbs. Investigations to identify the etiology of the disease included testing for several infectious agents known to cause encephalitis in carnivores. Tests for Toxoplasma gondii, Encephalitozoon cuniculi, Neospora caninum, canine distemper virus, rabies, adenovirus type 1, Borna disease virus, and Listeria monocytogenes were negative. The colony was closed, and the cause of the disease remains undetermined. 相似文献
77.
J?rg?MüllerEmail author Christian?Str?tz Torsten?Hothorn 《European Journal of Forest Research》2005,124(3):233-242
Analyses of land snails and habitat factors in acid beech forests were conducted in southern Germany (northern Bavaria). The
objectives were to study the effects of habitat characteristics on snail density and species richness. Habitat structures
were determined for 37 plots in one big forest. We found a significant relationship between the number of snail species and
individuals and the following set of habitat factors coverage of herbaceous layer, growing stock, mean diameter at breast
height of the three largest trees (DBHmax), stand age, total dead wood volume per ha, and advanced decomposed dead wood volume
per ha. We use maximally selected rank statistics to estimate cutpoints separating stands with low densities, from stands
with high snail densities. Here, we define cutpoints for a significant higher snail density at a stand age of 187 years, 57 m3/ha dead wood, 40 m3/ha advanced decomposed dead wood, 63 cm DBHmax and more than 1% herbaceous layer. For species richness, cutpoints are estimated
at 338 m3/ha stand volume, 170 years stand age, 50 m3/ha total dead wood amount, 15 m3/ha advanced decomposed dead wood and 56 cm DBHmax. The microhabitat analysis shows a higher pH value and a higher Calcium
content at the bottom of large snags and under large lying dead wood pieces in comparison to litter, upper mineral soil and
at the bottom of vital living trees. Snail species and individual density are significantly linked to these patterns of chemical
parameters. The identified cutpoints are a good base for ecological management decisions in forest management. 相似文献
78.
Direct seeding methods for nitrogen (N)-fixing tree-legumes by small-scale farmers were developed and studied in humid and
sub-humid areas of western Kenya. We focused on the first six months of establishment of calliandra (Calliandra calothyrsus Meissner) multipurpose hedgerows. Direct seeding became effective, reliable, and significantly better than for zero-control
treatments when improving A) water uptake by scratching the hard seeds with a sandal against a hard, rough surface, B) phosphorus (P) nutrition by mixing 150 g/m of kitchen wood-ash (1.3% P) into a 10 cm deep, 20 wide cm soil band 5 cm below
the seeds, and C) root nodulation by transferring 100 g/m Rhizobium-colonised soil, or 0.5 crushed, incubated nodule, from a calliandra hedge. The field germination was 90% after two weeks,
and the hedges were green and about 2 m tall in the dry season six months later.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
79.
Traute Jan?en Matthias Voss Michael Kühl Torsten Semmler Hans-Christian Philipp Christa Ewers 《Veterinary research》2015,46(1)
Erysipelothrix rhusiopathiae infections re-emerged as a matter of great concern particularly in the poultry industry. In contrast to porcine isolates, molecular epidemiological traits of avian E. rhusiopathiae isolates are less well known. Thus, we aimed to (i) develop a multilocus sequence typing (MLST) scheme for E. rhusiopathiae, (ii) study the congruence of strain grouping based on pulsed-field gel electrophoresis (PFGE) and MLST, (iii) determine the diversity of the dominant immunogenic protein SpaA, and (iv) examine the distribution of genes putatively linked with virulence among field isolates from poultry (120), swine (24) and other hosts (21), including humans (3). Using seven housekeeping genes for MLST analysis we determined 72 sequence types (STs) among 165 isolates. This indicated an overall high diversity, though 34.5% of all isolates belonged to a single predominant ST-complex, STC9, which grouped strains from birds and mammals, including humans, together. PFGE revealed 58 different clusters and congruence with the sequence-based MLST-method was not common. Based on polymorphisms in the N-terminal hyper-variable region of SpaA the isolates were classified into five groups, which followed the phylogenetic background of the strains. More than 90% of the isolates harboured all 16 putative virulence genes tested and only intI, encoding an internalin-like protein, showed infrequent distribution. MLST data determined E. rhusiopathiae as weakly clonal species with limited host specificity. A common evolutionary origin of isolates as well as shared SpaA variants and virulence genotypes obtained from avian and mammalian hosts indicates common reservoirs, pathogenic pathways and immunogenic properties of the pathogen.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0216-x) contains supplementary material, which is available to authorized users. 相似文献80.
Andreas VERNUNFT Mona SCHWERHOFF Torsten VIERGUTZ Mike DIEDERICH Andreas KUWER 《The Journal of reproduction and development》2015,61(1):74-79
The aim of this study was to investigate whether plasma anti-Muellerian hormone (AMH) levels of Holstein-Friesian heifers could be used to predict ovum pick-up (OPU) and embryo production outcomes. Plasma samples and data were collected from 64 heifers, which underwent repeated OPU with subsequent in vitro embryo production followed by embryo flushing after superovulation. AMH levels were significantly positively correlated with the number of follicles aspirated per OPU session (r = 0.45), recovered oocytes per OPU (r =0.43) and in vitro produced embryos per OPU (r = 0.28). No significant correlations between AMH and in vivo produced embryos were ascertained. Our results suggest that correlations between AMH and outcomes of an OPU-IVF program are too low to use AMH as a precise predictive parameter for the success of a particular OPU procedure in Holstein-Friesian heifers. However, AMH can help to identify groups of
very good or very poor oocyte donors. 相似文献