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排序方式: 共有297条查询结果,搜索用时 15 毫秒
1.
Kazuyoshi Nakata Tatsuo Hamano Ken-Ichi Hayashi Tadashi Kawai Seiji Goshima 《Fisheries Science》2001,67(3):449-455
SUMMARY: Preference for artificial burrows by the endangered Japanese crayfish species Cambaroides japonicus was studied to improve its cultivation. The occupation of artificial burrows, which were made from straight polyvinyl chloride pipes of different internal diameters ( Y , mm), by crayfishes of different total lengths ( X , mm) was significantly ( P < 0.001, n = 56) described by a linear regression: Y = 0.49 X + 3.42 (19.0 ≤ X ≤ 70.2). Among burrows of different lengths [crayfish total length (TL) × 1, × 2, × 3, and × 4], crayfishes significantly preferred burrows that were greater than TL × 3 ( P < 0.001, n = 588). 相似文献
2.
Narihito Ogawa Shoya Toyoshima Shinya Sekikawa Masahiro Ishijima Kyosuke Katagiri Chihiro Uematsu Tatsuya Hirano Akihito Ootaka Jun Suzuki 《Journal of Pesticide Science》2023,48(1):11
We investigated the synthesis and herbicidal activity of optically active cinmethylin, its enantiomer, and C3-substituted cinmethylin analogs. Optically active cinmethylin could be obtained in seven steps with the Sharpless asymmetric dihydroxylation of α-terpinene. The synthesized cinmethylin and its enantiomer showed similar herbicidal activity, which was independent of the stereochemistry. Next, we synthesized cinmethylin analogs with various substituents at the C3 position. We found that analogs with methylene, oxime, ketone, or methyl groups at the C3 position show excellent herbicidal activity. 相似文献
3.
Yamanaka T Yamada M Tsujimura K Kondo T Nagata S Hobo S Kurosawa M Matsumura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(3):293-296
The aim of this study was to investigate the pharmacokinetics of oseltamivir carboxylate (OC) in horses (n=6) after oral administration of its prodrug oseltamivir. The binding rate of OC to horse plasma proteins was negligible (<1%). Oral administration of oseltamivir of 2 mg/kg body weight of oseltamivir to horses provided a plasma concentration of OC (mean maximum concentration: 257.9 ng/ml) above the inhibitory concentrations against equine influenza A viruses determined in vitro. However, because OC is rapidly eliminated from horse plasma (mean elimination half-life: 2.5 hr), administration intervals should be less than 10 hr to retain a suitable concentration when using a single dose of 2 mg/kg oseltamivir. 相似文献
4.
The spawning grounds of the chub mackerel (Scomber japonicus) and spotted mackerel (Scomber australasicus) in the East China Sea were estimated based on catch statistics of the Japanese large- and medium-type purse seine fishery
from 1992 to 2006. Biometric data were obtained from specimens caught by purse seiners in the East China Sea from 1998 to
2006. Gonadosomatic index (GSI) at 50% sexual maturity of chub mackerel and spotted mackerel females was 2.5 and 2.6, respectively.
Using this criterion for GSI, chub mackerel larger than 275 mm and spotted mackerel larger than 310 mm in fork length were
considered to be mature. Mature chub mackerel was observed in the area of 15–22°C sea surface temperature (SST), and mature
spotted mackerel was observed in the area of 17–25°C SST. The spawning period of chub mackerel ranged from February to June,
and that of spotted mackerel ranged from February to May in the East China Sea. The spawning grounds were estimated from the
distributions of catch per unit effort (CPUE) of spawners and SST. As a result, the spawning ground of chub mackerel was estimated
to be in the central and southern part of the East China Sea and the area west of Kyushu in February, March, and April, and
in the central part of the East China Sea, the area west of Kyushu and Tsushima Straight in May, and in Tsushima Straight
and western part of the Sea of Japan in June. The spawning ground of spotted mackerel was estimated to be in the central and
southern part of the East China Sea and southern coastal area of Kyushu in February, March, and April, and the central and
southern part of the East China Sea and the area west of Kyushu in May. 相似文献
5.
Recording cerebellar neuron activities in swimming goldfish 总被引:1,自引:0,他引:1
ABSTRACT: Neuronal activities were investigated in the cerebellum of immobilized and swimming goldfish Carassius auratus . Extracellularly recorded neural activities of the cerebellum in immobilized goldfish were characterized and classified into five types. Based on the waveforms and recording depths, these five neural activity types were estimated to originate from three identified classes of cerebellar neurons: Purkinje cells, eurydendroid cells, and granule cells. Chronic recording of cerebellar neuron activities in unrestrained goldfish was performed for more than 100 h. During the chronic recordings, a submersible amplifier attached to the goldfish head, and a multielectrode array developed for the present study were used. Neuronal activities in the cerebellum of free-swimming fish could also be classified into five types as in the immobilized condition. Firing patterns of two neurons identified as Purkinje cells and eurydendroid cells were analyzed during turning movements of the goldfish. The firing patterns of these neurons changed in relation to turning movements. Although some improvements are required, the chronic recording method developed in the present study can be applied to further investigations concerning the direct relationship between brain neural activities and certain behavior. 相似文献
6.
Chihiro Kayo Seiji Hashimoto Atsunori Numata Masanori Hamada 《Journal of Wood Science》2011,57(3):234-240
We compared the greenhouse gas (GHG) emissions from a log pile (LP) to those from a sand compaction pile (SCP) and from cement
deep mixing (CDM) as measures against soil liquefaction, assuming that forest and waste management scenarios influence the
GHG (CO2, CH4, and N2O) balance of wood. We found little difference between the LP and SCP methods with respect to GHG emissions from fossil fuel
and limestone consumption. However, GHG emissions from the CDM method were seven times higher than emissions from the LP method.
In the GHG balance of wood, when the percentage of CH4 emissions from carbon in underground wood was lower than 3.3%, permanent storage in the log achieved greater reductions in
GHG emissions than using the waste log as fuel in place of coal or heavy oil. In order to obtain reductions in GHG emissions
by replacing SCPs or CDM with LPs, sustainable forest management with reforestation and prevention of CH4 emissions from the underground log are essential. Using reforestation, permanent storage of the log, no CH4 emission from the log, and using logging residues instead of coal, the LP can achieve reductions in GHG emissions of 121
tonnes of CO2 per 100 m2 of improvement area by replacing CDM. 相似文献
7.
Takuro Hirai Kei Sawata Ali Awaludin Yoshihisa Sasaki Takeyoshi Uematsu 《Journal of Wood Science》2012,58(2):128-134
Shaking table tests of the wall-floor joints of wooden light-frame constructions under forced harmonic vibrations are conducted
in this study so as to observe the dynamic responsive characteristics. The principal results are as follows: The responsive
characteristics of timber constructions under strong earthquakes cannot be directly correlated with their resonant frequencies
under free or forced vibrations with low input accelerations, because they behave as continuous bodies when the input accelerations
are less than the apparent frictional limits of structural joints. The apparent frictional limits are reduced by periodic
fluctuation of the effective vertical loads as a result of the vertical motion of the specimens. The characteristic dynamic
responses of wall-floor joints depend clearly upon the frequency and input accelerations of forced vibrations. These dependencies
arise from the nonlinear load-slip relationship of the wall-floor joints. The equivalent stiffness in their successive transient
phases decreases as joint slip increases, which gradually changes the resonant frequencies of the wall-floor joints. This
indicates that the frequency components dominant to ultimate or safety-limit resistance should be distinguished from those
dominant to allowable or serviceability-limit resistance. 相似文献
8.
For better understanding wood hardness, we developed a new hand-operated hardness tester that works with Brinell's method. With this tester we investigated the hardness distribution of wood minutely using a 2mm diameter ball tip. The following results were obtained: (1) On preliminary examination with medium-density fiberboard, we found that the value of Brinell's hardness decreased with the increase in the tip ball's diameter but that it was almost constant with the indenting velocity. (2) By using a small diameter tip, the difference of the hardness became clearer between earlywood and latewood. (3) With radial and tangential sections, we obtained hardness distribution patterns similar to those of wood grain. It seems that the hardness distribution reflects the distribution of density on wood surfaces. 相似文献
9.
(pp. 17–24)
A trial calculation was performed of the environmental nitrogen-assimilation capacity and the amount of nitrogen input based on various statistical data, which were compiled from each city, town and village in Hokkaido prefecture. The relationship between the excess quantity of nitrogen, after nitrogen input, and the environmental nitrogen-assimilation capacity and the nitrate-nitrogen concentration of the groundwater was considered.
Environmental nitrogen-assimilation capacity = nitrogen output by the crops + acceptable level of residual nitrate in the soil profile.*
* It is calculated by the amount of nitrate precipitation evapotranspiration ×10 mg L−1 .
A trial calculation was performed of the environmental nitrogen-assimilation capacity and the amount of nitrogen input based on various statistical data, which were compiled from each city, town and village in Hokkaido prefecture. The relationship between the excess quantity of nitrogen, after nitrogen input, and the environmental nitrogen-assimilation capacity and the nitrate-nitrogen concentration of the groundwater was considered.
Environmental nitrogen-assimilation capacity = nitrogen output by the crops + acceptable level of residual nitrate in the soil profile.*
- 1)
The average value of the environmental nitrogen-assimilation capacity in Hokkaido Prefecture was observed to be 183 kg ha
−1 . The maximum and minimum values of the environmental nitrogen-assimilation capacity were 308 kg ha−1 and 94 kg ha−1 , respectively. When the average value of the environmental nitrogen-assimilation capacity with respect to main agricultural land use was compared across municipalities, it was largely in the following order · grassland (218 kg ha−1 ), upland (169 kg ha−1 ), and paddy land (157 kg ha−1 ).
10.
Discrimination of “grazing milk” using milk fatty acid profile in the grassland dairy area in Hokkaido 下载免费PDF全文
Tomohiro Mitani Kuniyuki Kobayashi Koichiro Ueda Seiji Kondo 《Animal Science Journal》2016,87(2):233-241
Milk produced by the grazing system, referred to as “grazing milk” contains many components required for human health. The milk fatty acid (FA) profile is strongly associated with the diet on the farms. In the present study, based on the FA profile of farmer's bulk milk, we determined how to discriminate between milk produced on grazing and on a confinement system. A field survey was conducted four times (grazing and confinement season) in the Konsen (29 farms) and Okhotsk (25 farms) area in Hokkaido. Farmer's bulk milk samples and details of feeding management were collected and the FA profile of milk was measured. Milk produced during the grazing season contained less C16:0 and cis‐9 C16:0, and more C18:0, cis‐9 C18:1, trans‐11 C18:1, cis‐9,12 C18:2, cis‐9,trans‐11 C18:2 and cis‐9,12,15 C18:3 than milk produced during the confinement season. Discrimination analysis using 16 FA revealed that almost all milk samples were discriminated correctly (confinement season: 90% correct and 10% borderline, grazing season: 88% correct, 9% borderline and 3% incorrect). For farmers that were categorized incorrectly and were considered borderline in the grazing season, the dependency on pasture was low compared with that for farmers correctly discriminated. Therefore, to claim “grazing milk”, a high dependency on pasture is required for grazing dairy farmers. 相似文献