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121.
Yamaguchi A Clayton RN Mayeda TK Ebihara M Oura Y Miura YN Haramura H Misawa K Kojima H Nagao K 《Science (New York, N.Y.)》2002,296(5566):334-336
Eucrites are a class of basaltic meteorites that share common mineralogical, isotopic, and chemical properties and are thought to have been derived from the same parent body, possibly asteroid 4 Vesta. The texture, mineralogy, and noble gas data of the recently recovered meteorite, Northwest Africa (NWA) 011, are similar to those of basaltic eucrites. However, the oxygen isotopic composition of NWA011 is different from that of other eucrites, indicating that NWA011 may be derived from a different parent body. The presence of basaltic meteorites with variable oxygen isotopic composition suggests the occurrence of multiple basaltic meteorite parent bodies, perhaps similar to 4 Vesta, in the early solar system. 相似文献
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124.
P. H. Orr R. B. Toma S. T. Munson B. D’Appolonia 《American Journal of Potato Research》1982,59(12):605-611
Breads prepared from 5, 10, and 15% potato peel/white flour, 30% whole wheat flour, and 100% white flour plus two commercial, high fiber, dark breads in fresh and frozen/defrosted forms were evaluated sensorially by both untrained and trained panels. It appears that potato peel can be included in bread for the purpose of increasing dietary fiber without unduly sacrificing quality and acceptability. However, a musty aroma in the breads containing peel possibly influenced their flavor and overall rating scores, roughly in proportion to the amount of peel they contained. 相似文献
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126.
Nitrate Vulnerable Zones (NVZ) were introduced in response to the Nitrates Directive (91/676/EEC) which states that all EU countries must reduce the nitrate in drinking water to a maximum of 50 mg/l. Farmers within a designated NVZ must adhere to strict rules over the timing and application of nitrogen from organic and inorganic sources. In Scotland, four NVZ regions were designated in 2003, covering around 14% of the land area and affecting over 12,000 farmers.This paper outlines the results of a recent study to understand farmer activities in response to and attitudes towards NVZ regulations in Scotland. A telephone survey was administered, obtaining a response of 184 farmers, supplemented by four workshops held in each NVZ region. This explored, both quantitatively and qualitatively, farmer behaviour and attitudes.The bulk of farmers have made little capital investment since the 2003 designation. Few farmers have invested in increased slurry storage facilities, nor begun to transport more slurry off-farm, claiming to have had enough storage capacity before designation to cover the imposed closed period.Farmer attitudes indicate a mostly negative view towards the perceived environmental benefits, water management and compliance. This can be explained by a number of concerns raised by farmers towards the scientific basis for designations. Furthermore, farmers viewed the restrictions placed on farming practices within NVZs as too inflexible.Given the mostly sceptical perceptions demonstrated by the farmers we call for a more integrated approach to water management at the catchment level. There is a role for policy-makers to provide clearer information over the science and purpose of the designations and also to invest in the transfer of technologies, in particular N-use software which is specifically tailored to NVZ regulations. Also, critical to this would be the development of transparent indicators of water quality. This may start to embed nitrogen pollution impacts within the farmer's cultural framework of decision-making. 相似文献
127.
Abstract – Video cameras inside underwater housings were used to record the spawning behaviour of a subspecies of the white‐spotted charr, the amemasu charr (Salvelinus leucomaenis leucomaenis) in the Tokimae and Onbetsu Rivers, Hokkaido, Japan. Unlike other Salvelinus species, in which females use lateral swings of their bodies to ventilate and distribute eggs over gravel crevices (undulating) immediately after spawning, female amemasu charr covered their eggs with beats of their tails (cover digging). Cover digging right after spawning has previously been documented in Salmo, Oncorhynchus and Parahucho. Phylogenetic analysis of postspawning behaviours in the Salmoninae indicated that (i) resting then covering the eggs is plesiomorphic for the group, (ii) undulating replaced resting in the ancestor of Salvelinus, (iii) cover digging was advanced in the behavioural sequence to occur immediately after egg deposition in the ancestor of Parahucho + Salmo + Oncorhynchus and in the amemasu. 相似文献
128.
We developed a quantitative PCR assay for detecting the parasitic ciliate Cryptocaryon irritans, which causes “white spot disease” in marine fishes, from the natural environment. A specific primer set for C. irritans was designed and its high specificity was confirmed in silico: almost all of the sequences deposited in the GenBank nucleotide
database were covered, 22/23 for the forward primer and 7/7 for the reverse primer. We estimated that there were 3,415.9 rRNA
gene copies per genome of C. irritans. In artificial mixture experiments to validate whether the qPCR assay is applicable to natural samples, the estimated copy
numbers showed significantly positive correlations with the number of theronts added (p < 0.001). When we applied this qPCR assay to natural samples collected bimonthly from surface and bottom seawaters at an
aquaculture site (water depth, 10 m) from May 2009 to March 2010, we only detected C. irritans (112.0 ± 6.3 cells/l) in the surface seawater sample in November. This qPCR assay is a useful tool for detecting C. irritans rapidly and quantitatively in natural environments; it could also help advance our understanding of the ecology of C. irritans, as well as facilitate the diagnosis of the disease. 相似文献
129.
Takehiro Ohki Takahide Sasaya Mitsuru Sayama Tetsuo Maoka 《Journal of General Plant Pathology》2017,83(4):226-230
Polymyxa graminis is a soil-borne obligate organism that transmits bymoviruses and furoviruses to barley and wheat. We analyzed rDNA-ITS sequences of P. graminis from roots of wheat and barley in fields in Japan and obtained five kinds of sequences; two sequences were almost the same as known ribotype Ia and IIa, respectively, and three were close to ribotype Ib. When infection of P. graminis was examined using PCR, ribotype Ia was detected only in barley, but ribotypes Ib and IIa were detected in both wheat and barley. Our analysis suggested that Japanese ribotype Ib transmits furoviruses and bymoviruses. 相似文献
130.
Mitsuru NAITO 《Animal Science Journal》2003,74(3):157-168
The development of chicken embryo culture techniques, from single‐cell stage to hatching, makes it possible to manipulate developing embryos at any developmental stage. Production of germline chimeric chickens by the transfer of stage X blastodermal cells or primordial germ cells enables the manipulation of germline cells in vitro. Production of transgenic chickens has been attempted by the retroviral vector method, microinjection of DNA into a fertilized ovum at the single‐cell stage, use of chimeric intermediates produced by the transfer of stage X blastodermal cells or primordial germ cells, manipulation of spermatozoa, and in vivo manipulation of gonads. So far, the only non‐viral method that has successfully produced transgenic chickens is microinjection of DNA into a fertilized ovum. Manipulation of primordial germ cells could become an efficient system for producing transgenic chickens by combining it with the highly efficient transfection method or the in vitro culture system for primordial germ cells. Preservation of avian genetic resources has now become possible by cryopreservation of stage X blastodermal cells or primordial germ cells as well as spermatozoa. The development of nuclear transfer techniques for avian species is necessary. 相似文献