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81.
Five barrows (58 kg initial BW, 80 kg final BW) fitted with an ileo-rectal anastomosis were used to determine the effect of partial dehulling of two- and six-row barley varieties on the concentrations of ileal digestible amino acids (AA). The following diets were provided according to a standardized diet formulation and tested in five consecutive periods (repeated group-period design): two-row barley (TRB) + casein (C), dehulled TRB (TRB-H) + C, six-row barley (SRB) + C, dehulled SRB (SRB-H) + C, and wheat starch + C. Daily rates of approximately 80 g DM × kg BW− 0.75 in barley diets and 49 g DM × kg BW− 0.75 in the casein diet were supplied. The digestibility of AA in barley was determined by the difference method (casein as basal diet) using quantitative ileal effluent collection.

In TRB and SRB the ID of CP and AA did not differ. As demonstrated on selected key AA there were increases of both concentrations of gross AA and of ileal AA digestibility duo to dehulling. Consequently, the contents of ileal digestible AA were raised by up to 39% for lysine and 38% for methionine in TRB-H and SRB-H, respectively.  相似文献   

82.
Prostaglandin E2 (PGE2) is a crucial mediator of inflammatory pain sensitization. Here, we demonstrate that inhibition of a specific glycine receptor subtype (GlyR alpha3) by PGE2-induced receptor phosphorylation underlies central inflammatory pain sensitization. We show that GlyR alpha3 is distinctly expressed in superficial layers of the spinal cord dorsal horn. Mice deficient in GlyR alpha3 not only lack the inhibition of glycinergic neurotransmission by PGE2 seen in wild-type mice but also show a reduction in pain sensitization induced by spinal PGE2 injection or peripheral inflammation. Thus, GlyR alpha3 may provide a previously unrecognized molecular target in pain therapy.  相似文献   
83.
Mantle plumes and entrainment: isotopic evidence   总被引:8,自引:0,他引:8  
Many oceanic island basalts show sublinear subparallel arrays in Sr-Nd-Pb isotopic space. The depleted upper mantle is rarely a mixing end-member of these arrays, as would be expected if mantle plumes originated at a 670-kilometer boundary layer and entrained upper mantle during ascent. Instead, the arrays are fan-shaped and appear to converge on a volume in isotopic space characterized by low (87)Sr/(86)Sr and high (143)Nd/(144)Nd, (206)Pb/(204)Pb, and (3)He/(4)He ratios. This new isotopic component may be the lower mantle, entrained into plumes originating from the core-mantle boundary layer.  相似文献   
84.
Two new races of the wheat (Triticum aestivum L.) stem rust pathogen, representing the fifth and sixth variants described within the Ug99 lineage, were detected in South Africa. Races TTKSP and PTKST (North American notation) were detected in 2007 and 2009, respectively. Except for Sr24 virulence, race TTKSP is phenotypically identical to TTKSF, a commonly detected race of Puccinia graminis f. sp. tritici (Pgt) in South Africa. PTKST is similar to TTKSP except that it produces a lower infection type on the Sr21 differential and has virulence for Sr31. Simple sequence repeat (SSR) analysis confirmed the genetic relationship amongst TTKSF, TTKSP, PTKST and TTKSK (Ug99). TTKSK, PTKST and TTKSF grouped together with 99% similarity, while sharing 88% genetic resemblance with TTKSP. These four races in turn shared only 31% similarity with other South African races. It is proposed that both TTKSP and PTKST represent exotic introductions of Pgt to South Africa.  相似文献   
85.
The systemic effect of root colonization by the arbuscular mycorrhizal fungus (AMF) Glomus mosseae on the susceptibility of old and modern barley varieties to the soil-borne fungal pathogen Gaeumannomyces graminis var. tritici (Ggt) was studied in a split-root system. Plants were precolonized on one side of the split-root system with the AMF and thereafter the other side of the split-root system was inoculated with the pathogen. At the end of the experiment the level of bioprotection was estimated by quantifying lesioned roots and the determination of the root fresh weight. AM root colonization provided protection in some of the barley genotypes tested, but not in others. This protective effect seemed to vary in the oldest and the most modern barley variety tested.  相似文献   
86.
87.
During the 1980s many communities turned to grassroots activities to promote economic development, rather than relying on industrial recruitment strategies. We evaluate the characteristics of these projects, their benefits and costs, and obstacles they face in the development process. The data are drawn from a survey of more than one hundred communities in the United States. Self-development efforts do not appear to replace traditional rural economic development activities, but may complement them. Self-development activities produce a wide variety of jobs that are taken primarily by local residents. The cost and availability of credit are major obstacles for self-development projects. Although self-development strategies should not be considered the primary economic development strategy for most rural communities, they do enable communities to build a more viable local economy.  相似文献   
88.
89.
An 3 Lysimetermonolithen unterschiedlichen Bodentyps (Braunerde ‐ L5, Pseudogley ‐ L7, Schwarzerde ‐ L10) sowie an deren Herkunftsflächen (H5, H7, H10) wurden verschiedene bodenbiologische Parameter untersucht. Die mikrobiologischen Aktivitäten wiesen in allen Proben einen ausgeprägten Tiefengradienten auf und waren sogar z. T. bis in Tiefen von 175 cm noch nachweisbar (Biomasse, Basalatmung, DMSO‐Reduktion, alkalische Phosphatase). Die metabolischen Quotienten für CO2 waren auf den Herkunftsflächen meist deutlich niedriger als in den Lysimetern. Ob dieser Befund ebenso wie die etwas niedrigeren Cmik/Corg‐Quotienten der Lysimeter auf einen verminderten C‐Umsatz in den Lysimetern hinweisen könnte, muß durch weitere Untersuchungen geklärt werden. Die Erfassung der Mesofauna ergab größere Individuendichten für Collembolen und Milben (Braunerde) bzw. nur für Milben (Schwarzerde) in den Lysimetern, allerdings war hier das Untersuchungsmaterial für verallgemeinernde Aussagen nicht ausreichend.  相似文献   
90.

Purpose

In order to assess possible adverse effects originating from pulp deposits in a Swiss lake, a sediment quality triad approach was applied with chemical, ecotoxicological and ecological assessment methods.

Materials and methods

To obtain an integrative picture of the potential ecotoxicological effects on organisms of different trophic levels, four test procedures were applied. The acute effects of pulp deposit pore water on a decomposer, the amphipod Gammarus fossarum, were monitored. Chronic toxicity of the pore water was evaluated on primary producers via a growth inhibition test with unicellular green algae (Pseudokirchneriella subcapitata) and on secondary consumers in a reproduction test with the water flea Ceriodaphnia dubia. To evaluate the effects of the pulp deposit on sediment inhabitants, a whole-life-cycle test with the non-biting midge Chironomus riparius was undertaken. Chemical assessment included dissolved organic carbon, extractable organic halogenic compounds, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals. The composition of the macrozoobenthos community was analysed in order to assess the ecological effects.

Results and discussion

G. fossarum displayed increased locomotor activity at 12.5% but not at 25% sample concentration during a short-time exposure of 20 h. Chronic effects compromised the reproduction and growth of C. dubia (lowest observed effect concentration, 12.5% sample concentration) with zero population growth in 100% pulp deposit pore water. In 100% pulp deposit, C. riparius exhibited increased mortality at 10 and 17 days after oviposition. Pulp deposits of 50% and 100% concentration caused a significantly lower emergence compared with the reference treatments (lake sediment and quartz sand). Additionally, the locomotor activity of chironomids decreased significantly in 25–100% pulp deposit. No chronic effects of pulp deposit pore water on algae photosynthesis and growth could be detected. The bioassay results were in accordance with an elevated content of PAHs, PCBs and metals in the pulp deposit. Significantly more organisms known to be tolerant to organic pollution were present within the macrozoobenthos community.

Conclusions

In general, for sediment inhabitants such as chironomids, the pulp deposit has to be classified toxic. In the present test setup, the toxicity of the pulp deposit was reflected better by the chronic test systems applied than by the acute ones. The applied testing framework could be a suitable tool to assess the risk of contaminated sites, and this information will help decide whether risk mitigation measures should be taken. In addition, with a similar approach, the success of any mitigation measures taken can be assessed.  相似文献   
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