Development of soil fauna at mine sites during 46 years after afforestation     

Wolfram Dunger  Manfred Wanner  H. Hauser  K. Hohberg  H.-J. Schulz  T. Schwalbe  B. Seifert  J. Vogel  K. Voigtlnder  B. Zimdars  K.P. Zulka 《Pedobiologia》2001,45(3):243

  相似文献   

Occurrence of Salmonella spp. and shigatoxin-producing escherichia coli (STEC) in horse faeces and horse meat products     

Pichner R  Sander A  Steinrück H  Gareis M 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(7-8):321-325

In order to assess the relevance of horses as a possible reservoir of Salmonella and Shigatoxin-producing Escherichia coli (STEC), 400 samples of horse faeces and 100 samples of horse meat products were examined by PCR-screening methods. Salmonella enterica was not found in any of the samples. One faeces-sample and one horse meat product were proved to be STEC positive. The STEC-strain from faecal origin belonged to the serotype 0113:H21 and had the stx 2c gene and the enterohemolysin gene. The STEC-strain isolated from a horse meat product had the serotype O87:H16 and the stx 2d gene. The results indicate a very low risk for human to get a Salmonella- or EHEC- infection from horses in Germany.  相似文献   

Bruchpilot promotes active zone assembly, Ca2+ channel clustering, and vesicle release   总被引：1，自引：0，他引：1  

Kittel RJ  Wichmann C  Rasse TM  Fouquet W  Schmidt M  Schmid A  Wagh DA  Pawlu C  Kellner RR  Willig KI  Hell SW  Buchner E  Heckmann M  Sigrist SJ 《Science (New York, N.Y.)》2006,312(5776):1051-1054

The molecular organization of presynaptic active zones during calcium influx-triggered neurotransmitter release is the focus of intense investigation. The Drosophila coiled-coil domain protein Bruchpilot (BRP) was observed in donut-shaped structures centered at active zones of neuromuscular synapses by using subdiffraction resolution STED (stimulated emission depletion) fluorescence microscopy. At brp mutant active zones, electron-dense projections (T-bars) were entirely lost, Ca2+ channels were reduced in density, evoked vesicle release was depressed, and short-term plasticity was altered. BRP-like proteins seem to establish proximity between Ca2+ channels and vesicles to allow efficient transmitter release and patterned synaptic plasticity.  相似文献   

Toll-like receptor triggering of a vitamin D-mediated human antimicrobial response     

Liu PT  Stenger S  Li H  Wenzel L  Tan BH  Krutzik SR  Ochoa MT  Schauber J  Wu K  Meinken C  Kamen DL  Wagner M  Bals R  Steinmeyer A  Zügel U  Gallo RL  Eisenberg D  Hewison M  Hollis BW  Adams JS  Bloom BR  Modlin RL 《Science (New York, N.Y.)》2006,311(5768):1770-1773

In innate immune responses, activation of Toll-like receptors (TLRs) triggers direct antimicrobial activity against intracellular bacteria, which in murine, but not human, monocytes and macrophages is mediated principally by nitric oxide. We report here that TLR activation of human macrophages up-regulated expression of the vitamin D receptor and the vitamin D-1-hydroxylase genes, leading to induction of the antimicrobial peptide cathelicidin and killing of intracellular Mycobacterium tuberculosis. We also observed that sera from African-American individuals, known to have increased susceptibility to tuberculosis, had low 25-hydroxyvitamin D and were inefficient in supporting cathelicidin messenger RNA induction. These data support a link between TLRs and vitamin D-mediated innate immunity and suggest that differences in ability of human populations to produce vitamin D may contribute to susceptibility to microbial infection.  相似文献   

Comment on "Nonreciprocal light propagation in a silicon photonic circuit"     

Fan S  Baets R  Petrov A  Yu Z  Joannopoulos JD  Freude W  Melloni A  Popović M  Vanwolleghem M  Jalas D  Eich M  Krause M  Renner H  Brinkmeyer E  Doerr CR 《Science (New York, N.Y.)》2012,335(6064):38; author reply 38

We show that the structure demonstrated by Feng et al. (Reports, 5 August 2011, p. 729) cannot enable optical isolation because it possesses a symmetric scattering matrix. Moreover, one cannot construct an optical isolator by incorporating this structure into any system as long as the system is linear and time-independent and is described by materials with a scalar dielectric function.  相似文献   

Eucalyptus camaldulensis density and fiber length estimated by near-infrared spectroscopy     

Tetsuya Inagaki  Manfred Schwanninger  Reina Kato  Yohei Kurata  Warunee Thanapase  Pratuang Puthson  Satoru Tsuchikawa 《Wood Science and Technology》2012,46(1-3):143-155

Density and fiber length belong to the parameters that are used by the pulping industry as indicators of wood quality for different industrial processes and final paper products. The feasibility of Fourier transform near-infrared (FT-NIR) spectroscopy for the non-destructive evaluation of fiber length and air-dry density of fast-growing E. camaldulensis from Thailand was investigated using 50 samples. NIR spectra taken from solid wood and air-dry density as well as fiber length were used for partial least squares (PLS) regression analyses. It is the first time that the fiber length of E. camaldulensis solid wood could be predicted with high accuracy and precision and that the ratios of performance to deviation (RPD) obtained are the first that fully fulfill the requirements of AACC Method 39-00 (AACC 1999) for screening in breeding programs (RPD?≥?2.5). The RPDs for cross-validation (test set validation) of the NIR-PLS-R models of 3.3 (3.8) for air-dry density and 3.5 (3.9) for fiber length allow drawing the conclusion that the models are at least applicable for screening in breeding programs as they lie in-between screening (RPD?≥?2.5) and quality control (RPD?≥?5). Even when 40% of the samples were removed in cross-validation of the air-dry density model, the RPD is 3.2, which confirms that the model is robust, stable, and well qualified for prediction. The good model statistics obtained in this study might be due to the fact that measurement sites for the measurement of NIR spectra, air-dry density, and fiber lengths were strictly coincided.  相似文献   

A common near infrared—based partial least squares regression model for the prediction of wood density of Pinus pinaster and Larix?×?eurolepis     

Ana Alves  Antonio Santos  Philippe Rozenberg  Luc E. Paques  Jean-Paul Charpentier  Manfred Schwanninger  José Rodrigues 《Wood Science and Technology》2012,46(1-3):157-175

Wood density is defined as the ratio of mass to volume and therefore in principle it should be possible to calculate a unique partial least squares regression (PLS-R) model for several species. PLS-R models for wood density based on X-ray microdensity data were calculated for each species Pinus pinaster and Larix × eurolepis and for both species together. After cross-validation and test set validation the data sets were combined and final models were calculated. The common model gave a residual prediction deviation (RPD) of 3.1, a range error ratio (RER) of 11.7, and a SEP/SEC of 1.06. The single models for Pinus pinaster and Larix?×?eurolepis gave RPD’s of 3.5 and 3.2, RER’s of 13 and 11, and a SEP/SEC of 1.2. To the best knowledge of the authors all obtained PLS-R models are the first ones that fulfil the requirements according to AACC Method 39-00 (AACC in AACC Method, 39-00:15, 1999) to be used at least for screening (RPD?≥?2.5). Although this method and the defined limits were developed for the analysis of grains they can be used as a rough rule of thumb until limits for wood are available. The improvement of the PLS-R models, compared to published results, might be due to three facts (1) the higher number of scans collected for a single spectrum, (2) that the samples were better represented by the NIR spectra and X-ray microdensity values, and (3) that the sites for the measurement of NIR spectra and X-ray microdensity were coincided as strictly as possibly.  相似文献   

From wine to pepper: rotundone, an obscure sesquiterpene, is a potent spicy aroma compound   总被引：1，自引：0，他引：1  

Wood C  Siebert TE  Parker M  Capone DL  Elsey GM  Pollnitz AP  Eggers M  Meier M  Vössing T  Widder S  Krammer G  Sefton MA  Herderich MJ 《Journal of agricultural and food chemistry》2008,56(10):3738-3744

An obscure sesquiterpene, rotundone, has been identified as a hitherto unrecognized important aroma impact compound with a strong spicy, peppercorn aroma. Excellent correlations were observed between the concentration of rotundone and the mean 'black pepper' aroma intensity rated by sensory panels for both grape and wine samples, indicating that rotundone is a major contributor to peppery characters in Shiraz grapes and wine (and to a lesser extent in wine of other varieties). Approximately 80% of a sensory panel were very sensitive to the aroma of rotundone (aroma detection threshold levels of 16 ng/L in red wine and 8 ng/L in water). Above these concentrations, these panelists described the spiked samples as more 'peppery' and 'spicy'. However, approximately 20% of panelists could not detect this compound at the highest concentration tested (4000 ng/L), even in water. Thus, the sensory experiences of two consumers enjoying the same glass of Shiraz wine might be very different. Rotundone was found in much higher amounts in other common herbs and spices, especially black and white peppercorns, where it was present at approximately 10000 times the level found in very 'peppery' wine. Rotundone is the first compound found in black or white peppercorns that has a distinctive peppery aroma. Rotundone has an odor activity value in pepper on the order of 50000-250000 and is, on this criterion, by far the most powerful aroma compound yet found in that most important spice.  相似文献   

Interactions of local habitat type,landscape composition and flower availability moderate wild bee communities     

Neumüller  Ulrich  Burger  Hannah  Krausch  Sabrina  Blüthgen  Nico  Ayasse  Manfred 《Landscape Ecology》2020,35(10):2209-2224

Context

Landscape and local habitat traits moderate wild bee communities. However, whether landscape effects differ between local habitat types is largely unknown.

Objectives

We explored the way that wild bee communities in three distinct habitats are shaped by landscape composition and the availability of flowering plants by evaluating divergences in response patterns between habitats.

Methods

In a large-scale monitoring project across 20 research areas, wild bee data were collected on three habitats: near-natural grassland, established flower plantings and residual habitats (e.g. field margins). Additionally, landscape composition was mapped around the research areas.

Results

Our monitoring produced a dataset of 27,650 bees belonging to 324 species. Bee communities on all three habitats reacted similarly to local flower availability. Intensively managed grassland in the surrounding landscape had an overall negative effect on the studied habitats. Other landscape variables produced diverging response patterns that were particularly pronounced during early and late season. Bee communities in near-natural grassland showed a strong positive response to ruderal areas. Flower plantings and residual habitats such as field margins showed a pronounced positive response to extensively managed grassland and woodland edges. Response patterns regarding bee abundance were consistent with those found for species richness.

Conclusion

We advise the consideration of local habitat type and seasonality when assessing the effect of landscape context on bee communities. A reduction in the intensity of grassland management enhances bee diversity in a broad range of habitats. Moreover, wild bee communities are promoted by habitat types such as ruderal areas or woodland edges.

  相似文献   

A proposal of clinical breakpoints for amoxicillin applicable to porcine respiratory tract pathogens     

Schwarz S  Böttner A  Goossens L  Goosens L  Hafez HM  Hartmann K  Kaske M  Kehrenberg C  Kietzmann M  Klarmann D  Klein G  Krabisch P  Luhofer G  Richter A  Schulz B  Sigge C  Waldmann KH  Wallmann J  Werckenthin C 《Veterinary microbiology》2008,126(1-3):178-188

In the present position paper, an attempt was made to establish clinical breakpoints of amoxicillin to classify porcine respiratory tract pathogens as susceptible, intermediate or resistant based on their minimum inhibitory concentrations of amoxicillin. For this, a thorough review of the published literature with regard to swine-specific pharmacological data (including dosages of amoxicillin applied and routes of administration used), clinical efficacy, and in vitro susceptibility of the target pathogens was performed. Based on the comparative analysis of the results, the working group "Antibiotic Resistance" of the German Veterinary Medical Society (DVG) proposed to classify porcine respiratory tract pathogens that show MIC values of amoxicillin of < or =0.5microg/ml as "susceptible", those with MICs of 1microg/ml as "intermediate", and those with MICs of > or =2microg/ml as "resistant".  相似文献