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91.
In drought areas, in which topsoil moisture is low, barley seeds are generally sown in the subsoil (deep-seeding). In order for the shoots of germinating seeds to emerge from the deep soil cover, the coleoptile and the first internode of the seedlings must elongate as an adaptive response to deep-seeding. Here, we have mapped quantitative trait loci (QTLs) for these adaptive characteristics. Elongation of the coleoptile and first internode was investigated using seeds sown under two soil cover conditions: at a depth of 9 cm beneath a soil mixture; and, at a depth of 12 cm beneath vermiculite. We identified multiple alleles for increased coleoptile and first internode elongation using a doubled haploid population of 150 lines generated from a cross between the barley cultivars Harrington and TR306. Composite interval mapping analyses of the data revealed two moderate and eleven small effect QTLs, with at least one QTL on each chromosome. The QTLs on chromosomes 5H and 7H had moderate effects on coleoptile elongation (18.5–27.6% of PVE: phenotypic variance explained; 2.6–3.2 mm of Add: additive effect) and first internode elongation (PVE: 16.6–19.6%; Add: 3.1–3.2 mm). The small effect QTLs showed PVEs of less than 15% and an Add range of 1.2–3.2 mm for both characters. A marker assisted selection approach, using markers linked to the QTLs for seedling elongation at deep-seeding, may eventually enable development of drought tolerant barley hybrids.  相似文献   
92.
The forage quality of pasture species is spatially heterogeneous. In this study, we evaluated the dynamics and spatial structure of forage quality and attempted to relate the observed variation to differences in light availability and soil properties. We compared grass forage quality in open grasslands with forest edge environments and established plots in open Japanese grasslands surrounded by secondary forests. We sampled Anthoxanthum odoratum L. and soil from each plot in May and September. These samples were analyzed to determine the crude protein (CP), neutral detergent fiber, and mineral concentrations. We calculated Moran’s I coefficients across discrete lag distance classes to construct autocorrelograms. The CP model showed a non-random pattern in May at a lag distance of 40 m, but a clustered pattern in September at a small scale. The mineral models produced similar clustered spatial patterns. We found no strong correlation between aboveground (plant) and belowground (soil) mineral contents. CP and some mineral element concentrations in the plants collected in September were significantly greater at the forest edge than in open grasslands. The forest edge therefore appears to be a valuable place to provide grazing animals with adequate protein and mineral intake during the later part of the growing season.  相似文献   
93.
The multiplication of Akabane virus was not inhibited in the presence of 5-iodo-2′-deoxyuridine, indicating the presence of RNA. The virus was considered to have an envelope, as it was sensitive to ether and chloroform. It was readily inactivated by deoxycholate and trypsin, but was not precipitated by protamine sulphate. The virus was very labile at pH 3 and also rather heat-labile. Akabane virus was readily filtered through membrane filters of 200 or 100-nm pore size, but not through 50-nm filters. Equilibrium centrifugation in a CsCl density gradient gave a peak of infectivity and hemagglutinin at a density of 1.22 g/ml. The peak fractions thus obtained contained numerous virus particles, roughly spherical, variable in size, 70 to 130 nm in diameter, and mostly having a ragged, closely adherent envelope with projections, when examined, following phosphotungstic acid negative staining, in an electron microscope.  相似文献   
94.
95.
The Standard for the Exchange of Nonclinical Data (SEND), adopted by the US FDA, is part of a set of regulations and guidances requiring the submission of standardized electronic study data for nonclinical and clinical data submissions. SEND is the nonclinical implementation of SDTM (Study Data Tabulation Model), the standard electronic format for clinical regulatory submissions to FDA. SEND, SDTM, and the associated Controlled Terminology have been developed by CDISC (Clinical Data Interchange Standards Consortium). In order to successfully implement SEND, interdisciplinary contributions between sponsors and CROs, need a model for task allocation. This is being undertaken by the Pharmaceutical Users Software Exchange (PhUSE). Because SEND is currently the preferred submission format of the US FDA only and will become required by it starting in December 2016, only American academic societies and companies are actively involved. An exception to this is the INHAND initiative, which leads the way in standardizing terminology for toxicological pathology. On the other hand, international globalization of other clinical and nonclinical practices is not feasible because there are substantial differences between the US and non-US countries in CRO involvement in drug development. Thus, non-US countries must consider and develop approaches to SEND that meet their needs. This paper summarizes the activities of the major organizations involved in SEND development and implementation, discusses the effective use of SEND, and details a compliance scheme (research material of the Showa University School of Medicine) illustrating how pharmaceutical companies can complete a large amount of work up to an FDA application with the effective utilization of CROs and solution providers.  相似文献   
96.
Summary

Leaf fragments of fig (Ficus carica L. ‘Masui Dauphine’) regenerated from in vitro shoot culture were excised and inoculated on MS medium supplemented with different combinations of 2, 4-D, TDZ, and 0.5 mM phloroglucinol. Addition of 2, 4-D induced root formation directly on the explant, and the presence of phloroglucinol significantly increased root formation. When a combination of 2, 4-D and TDZ was added to MS medium containing phloroglucinol, the explants started to produce adventitious buds at the edges. The addition of phloroglucinol was effective in inducing adventitious bud formation. Excised shoots were rooted successfully in MS medium that was either hormone free or supplemented with 1.0 mg l–1 indolebutyric acid. Regenerated plantlets were successfully established in soil after a short period of acclimatization. This is the first protocol of organogenesis and plant regeneration from vegetative organs of Ficus carica L.  相似文献   
97.
Binderless boards were prepared from finely ground powders of kenaf (Hibiscus cannabinus L.) core under varying manufacturing conditions. This research was designed to investigate their mechanical properties and evaluate the various manufacturing conditions: pressing temperature and time, pressing pressure, board density, board thickness, grain size of raw materials, and addition of furfural. The mechanical properties (i.e., modulus of rupture and elasticity, internal bonding strength) of boards increased with increasing board density and met the requirement for 15 type medium-density fiberboard (MDF) by JIS A 5905-1994. Thickness swelling and water absorption of boards exceeded the maximum permitted levels for 15 type MDF and S20 grade hardboard by JIS A 5905-1994, which indicates the low water-resistant property of binderless boards. In contrast to that in usual wood-based materials, internal bonding strength showed significant correlations with other board properties: modulus of rupture and elasticity, thickness swelling, and water absorption. We confirmed experimentally that the best manufacturing conditions proved to be as follows: pressing temperature 180°C, time 10min; pressing pressure 5.3MPa; board thickness 5mm; board density 1.0g/cm3; average grain size 53µm; and powder with no furfural content.Part of this paper was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002  相似文献   
98.
To demonstrate the effect of excess soil moisture on the decline of a coastal Pinus thunbergii stand in Oshamanbe, southwestern Hokkaido, Japan, soil moisture content was monitored for 4 years. The saturated hydraulic conductivities (K S) of different soil types (coastal sand, supplied topsoil, and buried concreted andosol) and the distribution of the buried concreted andosol layer were investigated. We also examined needle length to verify the real-time response of P. thunbergii to excess soil moisture. Soil moisture content at the heavily damaged site was more heterogeneous than that at the slightly damaged site, and a sensor near the ground always reported a higher soil moisture content at the heavily damaged site than at the slightly damaged site. The buried concreted andosol layer was always found at the heavily damaged site. The K S of the andosol layer was 10−5, suggesting that this layer is less permeable to water, leading to excess soil moisture at this site. P. thunbergii needles from the heavily damaged site were shorter than those from the slightly damaged site, possibly because of water stress. Together with other symptoms observed at the study sites, i.e., crown dieback and intense lateral growth, this information leads us to conclude that the decline of P. thunbergii stands at the heavily damaged site in Oshamanbe was caused by excess soil moisture due to the less permeable buried concreted andosol layer.  相似文献   
99.
We describe a split-root system for examining the effects of hydraulic lift by trees on crop growth. In this system, upper lateral tree roots were grown in a container set on the ground through which the taproot of the tree could penetrate into the moist soil below. The container, with a radius of 0.5 m and a height of 0.20 m, consisted of two compartments divided by a waterproof barrier. A markhamia tree (Markhamia lutea (Benth.) Schumann) and upland rice (Oryza sativa (L.)) plants were planted in one compartment, with only rice plants planted in the other compartment. Irrigation of the container was ceased at the start of the experiment. The stomatal conductance of the rice plants in the associated side, in which both trees and rice plants were grown, declined more rapidly during the first drying period than in the rice-only compartment, suggesting that there was competition for water between the tree and the crop plants. However, during the later drying period, the rice plants in the associated side were green and viable, while those in the rice-only side became desiccated. Rice roots were seen intermingling with tree roots, and the soil water content in the associated site tended to be higher than in the rice-only side. It is likely that hydraulic lift occurred in the associated side and that water that had been transferred to the surface roots was released into the soil, enabling the rice plants in this compartment to remain viable. This novel system is useful for examination of the effects of hydraulic lift by trees on the growth of neighbouring crops. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
100.
This study examined the bending creep behavior of hot-pressed wood during cyclic moisture changes. Sugi (Cryptomerica japonica D. Don) specimens were pressed in the radial direction under six combinations of nominal compressive strain (33% and 50%) and press temperatures (140°C, 170°C, 200°C). Creep tests were conducted at 20°C with three cyclic relative humidity changes between 65% and 95% under 25% of short-breaking stress. The effect of moisture content (MC) change on elastic compliance and mechanosorptive (MS) compliance was investigated. The relation between MS compliance and thickness swelling was studied. The results indicated that total compliance increased over the history of cyclic moisture changes; and its behavior was closely related to the changes in MC and thickness swelling. The total compliance increased during adsorption and decreased during desorption. Elastic compliance increased linearly with MC and was dependent on press temperature and compression. With increasing MC change, MS compliance increased during adsorption and decreased during desorption. The first adsorption led to greater MS compliance than did the subsequent adsorption with the same amount of MC change. In general, the elastic parameterK E and the MS parameterK Mincreased with compression and decreased as the press temperature increased. The MS parameterK M was apparently greater than the elastic parameterK E. The MS parameterK M increased with swelling coefficient KSW of the hot-pressed specimen during adsorption and decreased with an increasing shrinkage coefficientK SH during desorption.  相似文献   
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