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121.
Torben Schulz‐Streeck Joseph O. Ogutu Andrés Gordillo Zivan Karaman Carsten Knaak Hans‐Peter Piepho 《Plant Breeding》2013,132(6):532-538
Genomic selection has been routinely implemented in plant breeding in two stages. The first stage usually omits the marker information and estimates adjusted means of genotypes across environments. The second stage uses the adjusted means to predict genomic breeding values. However, if the effects of markers vary substantially between different environments, it may be important to account for this variation for varieties adapted to different environments. Using two maize data sets, we investigated whether modelling the marker‐by‐environment interaction can improve the predictive ability of genomic selection relative to modelling genotype‐by‐environment interaction alone. Modelling the marker‐by‐environment interaction did not substantially increase the predictive ability relative to modelling only the genotype‐by‐environment interaction for the two tested data sets. Thus, genomic selection, carried out in a stagewise fashion, such that the marker information is omitted until the last stage of the process, may suffice for most practical purposes. Moreover, predictive ability did not reduce substantially even when the number of markers with consistent effects across environments used for genomic prediction was reduced to about 50. 相似文献
122.
The influence of curing conditions on the chemical distribution in wood modified with thermosetting resins 总被引:1,自引:0,他引:1
Scots pine (Pinus sylvestris L.) sapwood was impregnated with aqueous solutions of phenol formaldehyde and methylated melamine formaldehyde resins and subsequently cured in an oven. One set of specimens was cured in plastic bags to avoid drying (wet curing) while another set of samples was heated and water was allowed to freely evaporate (dry curing). Macroscopic resin distribution was investigated using X-ray densitometry and infrared spectroscopy (FTIR-ATR). During dry curing, the resins migrated to the wood surface resulting in a gradient. Wet curing resulted in even distribution of the resins because it was immobilized due to condensation and precipitation in the wood. Neither densitometry nor FTIR-ATR was found to be generally applicable for investigating resin distribution in modified wood. Wet curing resulted in low cell wall bulking as compared to dry curing, probably because resin precipitated before drying. Storing impregnated wood prior to curing under non-drying conditions (“diffusion phase”) also reduced cell wall penetration and bulking. 相似文献
123.
Andre C Shih Alessio Vigani Nichole Loring Fernando G Pereira Mark Szarowicz Carsten Bandt 《Veterinary anaesthesia and analgesia》2010,37(3):215-221
ObjectiveTo compare the hemodynamic and respiratory effects of an inspiratory impedance threshold device (ITD) in anesthetized normotensive and hypotensive dogs.Study designProspective randomized study.AnimalsTen adult dogs.MethodsDogs were anesthetized with propofol followed by isoflurane. During spontaneous ventilation, tidal volume ( ), systolic (SAP), mean (MAP) and diastolic arterial blood pressure, central venous pressure, gastric PCO2 as an indicator of gastric perfusion, subcutaneous oxygen tension, subcutaneous blood flow, cardiac index (CI), systemic vascular resistance and blood lactate were monitored. To monitor respiratory compliance (RC) and resistance (ResR), animals were briefly placed on mechanical ventilation. Dogs were studied under four different conditions: 1) normotension (MAP > 60 mmHg) with and without the ITD and 2) hypotension (target MAP = 40 mmHg) with and without ITD. These four conditions were performed during one anesthetic period, allowing for stabilization of parameters for each condition. Data were analyzed by anova repeated measure mixed models.ResultsNo cardiovascular changes were detected between no ITD and ITD in the normotensive state. During hypotension, CI was higher with the ITD (5 ± 1.0 L minute?1 m?2) compared with no ITD (4 ± 1.3 L minute?1 m?2). During hypotension, SAP was increased with ITD (80 ± 14 mmHg) versus without ITD (67 ± 13 mmHg). There was an increase in ResR and decreased RC with the ITD in both normotensive and hypotensive state.Conclusion and clinical relevanceImpedance threshold device in dogs during isoflurane-induced hypotension improved CI and SAP but had negative effects on RC and ResR. 相似文献
124.
Paul C Reunamo A Lindehoff E Bergkvist J Mausz MA Larsson H Richter H Wängberg SÅ Leskinen P Båmstedt U Pohnert G 《Marine drugs》2012,10(4):775-792
Several marine and freshwater diatoms produce polyunsaturated aldehydes (PUA) in wound-activated processes. These metabolites are also released by intact diatom cells during algal blooms. Due to their activity in laboratory experiments, PUA are considered as potential mediators of diatom-bacteria interactions. Here, we tested the hypothesis that PUA mediate such processes in a close-to-field mesocosm experiment. Natural plankton communities enriched with Skeletonema marinoi strains that differ in their PUA production, a plankton control, and a plankton control supplemented with PUA at natural and elevated concentrations were observed. We monitored bacterial and viral abundance as well as bacterial community composition and did not observe any influence of PUA on these parameters even at elevated concentrations. We rather detected an alternation of the bacterial diversity over time and differences between the two S. marinoi strains, indicating unique dynamic bacterial communities in these algal blooms. These results suggest that factors other than PUA are of significance for interactions between diatoms and bacteria. 相似文献
125.
126.
Florian Nagel Arndt von Danwitz Michael Schlachter Saskia Kroeckel Carola Wagner Carsten Schulz 《Aquaculture Research》2014,45(12):1964-1978
Antinutritional factors in rapeseed products have been identified to reduce feed palatability and growth performance of turbot. Therefore, we evaluated the potential of blue mussel (Mytilus edulis L.) meal as feed attractant in rapeseed protein‐based diets for turbot. Triplicate fish groups received isonitrogenous and isocaloric diets with fish meal (FM) protein replacements of 50% or 75% by rapeseed protein concentrate (RPC 50, RPC 75). These diets were supplemented with 0%, 2%, 4% or 8% of blue mussel meal. In contrast with RPC 50 diets, fish fed with RPC 75/0 showed significantly reduced daily feed intake (DFI) and specific growth rate (SGR). With increasing mussel meal inclusion, RPC 75 diets resulted in increased DFI and SGR, suggesting mussel meal as attractant in rapeseed protein‐based diets for turbot. Feed conversion was unaffected by any treatment. Protein productive value and apparent digestibility coefficients were unaffected by either RPC or mussel meal inclusion. With regard to the whole body composition, no differences in crude protein, crude lipid and ash content could be determined. Haematological characteristics were unaffected among the treatments indicating good nourished and unstressed fish. In conclusion, we demonstrated that the utilization of blue mussel meal improved the palatability of rapeseed protein‐based diets for turbot. 相似文献
127.
Bir Bahadur Khanal Chhetri Helle Overgaard Larsen Carsten Smith-Hall 《Small-Scale Forestry》2012,11(4):435-452
Decentralised forest management is believed to hold potential for increased economic and social equity. Implications of the associated local forest law enforcement on livelihoods, however, are not well understood. This paper explores the impacts of local forest law enforcement with a focus on the poorest forest users in community-managed forests. A case study including 14 community forest groups in western Nepal was conducted in 2008. Methods included review of archival data, a stakeholder survey (n?=?211), and recall of forest crimes by a random household sample (n?=?252). Local forest law enforcement was found to detect far more crimes than district-level enforcement. Crimes are primarily small-scale unauthorised appropriation of products for subsistence use by poorer households and rules are lightly enforced. It is argued that local law enforcement, while apparently not economically harmful to the poorer in the short term, may be used to perpetuate existing wealth and cast-based social inequities. 相似文献
128.
Zefang Xiao Yanjun Xie Stergios Adamopoulos Carsten Mai 《Wood Science and Technology》2012,46(4):749-767
Scots pine sapwood was treated with glutaraldehyde (GA) in aqueous solution using magnesium chloride as a catalyst in order to evaluate the durability towards weathering. Infrared spectroscopy suggested that GA treatment increased the photo-stability of lignin during artificial weathering of micro-veneers in a QUV over 168?h; photo-protection increased with increasing GA concentration. In comparison with the unmodified controls, GA-modified pine micro-veneer strips exhibited a lower tensile strength loss measured in a zero-span mode in the course of weathering. During 18?months of outdoor exposure, GA-modified pine wood boards exhibited a lower moisture content and water uptake than the unmodified ones. GA treatment also clearly restricted the penetration of blue stain fungi into deeper layers of wood. On the macroscopic scale, the surface of the GA-modified boards was significantly smoother due to less erosion, cracking and minor peeling of tracheids. Scanning electron microscopy further revealed that individual tracheids were detached from the cell compound and then washed away from the unmodified wood surface, whereas tracheids on surfaces of GA-modified wood remained in the tissue compound but displayed many axial and transversal cracks. 相似文献
129.
Soil organic carbon stocks,distribution, and composition affected by historic land use changes on adjacent sites 总被引:1,自引:0,他引:1
Historic alterations in land use from forest to grassland and cropland to forest were used to determine impacts on carbon
(C) stocks and distribution and soil organic matter (SOM) characteristics on adjacent Cambisols in Eastern Germany. We investigated
a continuous Norway spruce forest (F-F), a former cropland afforested in 1930 (C-F), and a grassland deforested in 1953 (F-G).
For C and N stocks, we sampled the A and B horizons of nine soil pits per site. Additionally, we separated SOM fractions of
A and B horizons by physical means from one central soil pit per pedon. To unravel differences of SOM composition, we analyzed
SOM fractions by 13C-CPMAS NMR spectroscopy and radiocarbon analysis. For the mineral soils, differences in total C stocks between the sites
were low (F-F = 8.3 kg m−2; C-F = 7.3 kg m−2; F-G = 8.2 kg m−2). Larger total C stocks (+25%) were found under continuous forest compared with grassland, due to the C stored within the
organic horizons. Due to a faster turnover, the contents of free particulate organic matter (POM) were lower under grassland.
High alkyl C/O/N-alkyl C ratios of free POM fractions indicated higher decomposition stages under forest (1.16) in relation
to former cropland (0.48) and grassland (0.33). Historic management, such as burning of tree residues, was still identifiable
in the subsoils by the composition and 14C activity of occluded POM fractions. The high potential of longer lasting C sequestration within fractions of slower turnover
was indicated by the larger amounts of claybound C per square meter found under continuous forest in contrast to grassland. 相似文献
130.
Markus Steffens Angelika Kölbl Marcus Giese Carsten Hoffmann Kai Uwe Totsche Lutz Breuer Ingrid Kögel‐Knabner 《植物养料与土壤学杂志》2009,172(1):78-90
It is not clear from the literature how the spatial distribution of topsoil and vegetation properties is affected by grazing cessation. Thus, the objective of this study was to elucidate if long‐term grazing exclosure increases spatial heterogeneity of topsoil and vegetation properties in a steppe ecosystem in NE China. Variograms and crossvariograms were calculated for bulk density, organic carbon (OC), total N, and total S concentration, δ13C, pH, Ah horizon thickness, vegetation cover, and aboveground biomass. Five sites with different grazing intensities (ungrazed since 1979, ungrazed since 1999, winter grazing, continuously grazed, heavily grazed) were sampled with two different grid sizes, allowing the exploration of scale effects. Small grids (15 m spacing, 5 m nested sampling) exhibited a different spatial structure compared to large grids (50 m spacing, 10 m nested sampling). Spatial distribution in small grids changed with grazing intensity. Generally, heterogeneity of topsoil properties increased with decreasing grazing intensity from a homogeneous to a patchy distribution. We attribute this to vegetation recovery/succession and deposition of windblown material in ungrazed areas. The plot ungrazed since 1999 showed different spatial dependencies than continuously and heavily grazed plots, but has not yet reached the high variability of the plot which was ungrazed since 1979. Large grid sampling did not detect small‐scale variability or grazing impacts, but showed spatial dependencies that were attributed to topography or soil erosion/deposition. Low OC concentration and low Ah thickness were associated with hilltop and shoulder positions, resulting in lower OC stocks at these topographic units. 相似文献