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排序方式: 共有985条查询结果,搜索用时 15 毫秒
1.
Fisheries Science - Bioturbation by the sand dollar Scaphechinus griseus is suspected to inhibit the recruitment of Pseudocardium sachalinense, a commercially important bivalve. This study aimed to... 相似文献
2.
Vongvichith Bounsong Morioka Shinsuke Sugita Tsuyoshi Phousavanh Nokjalia Phetsanghanh Norkeo Chanthasone Phonaphet Pommachan Phoutsamone Nakamura Satoshi 《Fisheries Science》2020,86(1):145-151
Fisheries Science - The growth of the climbing perch Anabas testudineus reared on lower protein feeds with the replacement of fishmeal (FM) by prepupae of the black soldier fly (BSF) Hermetia... 相似文献
3.
Tanaka Tatsuya Ikeda Ryunosuke Yuta Yuta Tsurukawa Kanji Nakamura Satoshi Yamaguchi Takeharu Komeyama Kazuyoshi 《Fisheries Science》2019,85(6):1037-1043
Fisheries Science - In aquaculture, periodic measurement of fish body size is required to suitably assess growth progress. The aim of this study is to monitor the growth of free-swimming red sea... 相似文献
4.
Paddy fields converted into winter wheat fields in Hokkaido, Japan, receive extremely high snowfall, creating a risk of flood damage to crops in spring due to waterlogging of snowmelt runoff and poor drainage. Meanwhile, in June there is relatively little rainfall, and a lack of moisture inhibits winter wheat growth. Therefore, we developed a method involving a series of 30-cm-deep ditches in agricultural fields to be used for drainage during the flood-prone period and for furrow irrigation during the dry period using water drawn from the canals that feed the paddy fields. The ditches are called ‘hybrid ditches’ as they are able to perform both drainage and irrigation functions. In this study, we investigated the optimal construction timing and spacing for hybrid ditches. We also evaluated their ability to improve the drainage and irrigation of winter wheat. We found that the optimal timing for digging hybrid ditches is immediately after sowing, and the inter-ditch spacing for irrigation should be 15 m or less. The hybrid ditches promoted increased soil temperature and healthy development of wheat plants by improving drainage during the flood-prone period. In addition, water was successfully supplied via the hybrid ditches to irrigate the fields in June. Under experimental conditions in which rainfall was excluded, grain yield was 10% higher and percent protein content was more than 1% point greater in the irrigated plot compared with the non-irrigated plot. Grain yield was also observed to increase by 3–29% in demonstration tests conducted at local farms. From these results, we conclude that hybrid ditches are capable of improving the growth and yield of winter wheat by improving drainage and providing irrigation in converted paddy fields in Hokkaido. 相似文献
5.
Surgical correction of gastro‐oesophageal intussusception with bilateral incisional gastropexy in three dogs 下载免费PDF全文
Three dogs presented for evaluation of acute onset tachypnoea and dyspnoea following episodes of vomiting and/or regurgitation. Thoracic radiographs were suggestive of a gastro‐oesophageal intussusception in all three dogs; one dog also showed evidence of aspiration pneumonia. All three dogs underwent surgical correction with a bilateral incisional gastropexy. All dogs recovered from anaesthesia uneventfully and were discharged from the hospital 3 days after presentation. Persistent megaoesophagus was evident in all three dogs, and they are being chronically managed with a strict feeding regime and pro‐motility agents. 相似文献
6.
Vitamin D Status in Different Stages of Disease Severity in Dogs with Chronic Valvular Heart Disease 下载免费PDF全文
T. Osuga K. Nakamura T. Morita S.Y. Lim K. Nisa N. Yokoyama N. Sasaki K. Morishita H. Ohta M. Takiguchi 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1518-1523
Background
In humans with heart disease, vitamin D deficiency is associated with disease progression and a poor prognosis. A recent study showed that serum 25‐hydroxyvitamin D [25(OH)D] concentration, the hallmark of vitamin D status, was lower in dogs with heart failure than in normal dogs, and a low concentration was associated with poor outcome in dogs with heart failure.Objectives
To elucidate the vitamin D status of dogs with chronic valvular heart disease (CVHD) at different stages of disease severity.Animals
Forty‐three client‐owned dogs with CVHD.Methods
In this cross‐sectional study, dogs were divided into 3 groups (14 dogs in Stage B1, 17 dogs in Stage B2, and 12 dogs in Stage C/D) according to ACVIM guidelines. Dogs underwent clinical examination including echocardiography. Serum 25(OH)D concentrations were measured in each dog.Results
Serum 25(OH)D concentration was significantly lower in Stage B2 (median, 33.2 nmol/L; range, 4.9–171.7 nmol/L) and C/D (13.1 nmol/L; 4.9–58.1 nmol/L) than in Stage B1 (52.5 nmol/L; 33.5–178.0 nmol/L) and was not significantly different between Stage B2 and Stage C/D. Among clinical variables, there were significant negative correlations between 25(OH)D concentration and both left atrial‐to‐aortic root ratio and left ventricular end‐diastolic diameter normalized for body weight.Conclusions and Clinical Importance
These results indicate that vitamin D status is associated with the degree of cardiac remodeling, and the serum 25(OH)D concentration begins to decrease before the onset of heart failure in dogs with CVHD. 相似文献7.
8.
Yasuyuki Tachiki Tetsuhiko Yoshimura Hisashi Hasegawa Tomonori Mita Tetsuro Sakai Futoshi Nakamura 《Journal of Forest Research》2005,10(6):419-427
The objectives of this study were to determine Global Positioning System (GPS) positional errors while moving under the forest
canopy and to clarify the effects of polyline simplification on area and perimeter estimations. We used the Pathfinder Pro
XR and GPSMAP 76S, which are categorized as “high-end mapping” and “general navigation” GPS receivers, respectively. The field
tests were conducted in both natural and plantation forests. The results showed that the Pathfinder Pro XR, which has better
multipath rejection technology, worked well, especially in the plantation forest under unfavorable conditions of higher stand
density. We used analysis of variance to clarify the effects of the receiver type, positioning mode, stand type, and polyline
simplification method on area and perimeter estimations. The receiver type and positioning mode were found to be significant
factors that affected area estimation. The Pathfinder Pro XR estimated the area more accurately than the GPSMAP 76S, and differential
GPS estimated the area more accurately than autonomous GPS. With respect to the perimeter, the receiver type, positioning
mode, and polyline simplification method were found to be significant factors. The results showed that perimeter estimation
was improved by using the velocity filter, and further improved by using the velocity filter and Douglas-Peucker algorithm,
especially when the Pathfinder Pro XR was used. The GPSMAP 76S estimated the perimeter accurately without any filtering because
its default speed filter worked well, even though the GPSMAP 76S is a general navigation GPS receiver. 相似文献
9.
We compared patterns of acorn dispersal and predation by wood mice among four tree species (Quercus serrata, Quercus crispula, Castanea crenata, and Juglans mandshurica var. sieboldiana) that are abundant in cool temperate woodlands. We devised an acorn dispersal experiment using 400 magnet-inserted acorns and a magnetic locator in a 1.8-ha study plot, which spanned a cut-over area and an adjacent deciduous forest. Ten wire mesh baskets, each containing 40 acorns (10 acorns per species), were placed on the border between these two habitat types. About 13.0% (n = 52) of the total acorns remained in the baskets, while 77.3% (n = 309) were dispersed throughout the study plot and subsequently retrieved using the magnetic locator. Microhabitat, distance, and burial depth of transported acorns were significantly different among species. In the cut-over area, J. mandshurica var. sieboldiana acorns were dispersed under fallen trees or branches and near stumps, and were buried deeply in the soil. Dispersal distances of J. mandshurica var. sieboldiana acorns were significantly greater than those of Q. serrata acorns. The number and microhabitat of transported acorns significantly differed between habitat types. J. mandshurica var. sieboldiana acorns were dispersed in the cut-over area rather than in the forest. For all four species, the numbers of acorns delivered to fallen trees or branches, stumps, and crumbled soil with overhang under any vegetation type were greater in the cut-over area than in the forest. 相似文献
10.
Amin Setyo Leksono Kenta Takada Nobukazu Nakagoshi Koji Nakamura 《Journal of Forest Research》2006,11(1):61-64
A continuous sampling of canopy beetles was carried out to determine variations in the abundance, species diversity, richness,
and composition of the Mordellidae and Cerambycidae in a coppice woodland. Changes in the abundance and the species richness
were monitored at three heights in the forest throughout the season in 1999, using yellow and blue water pan traps. The results
showed significant variations in the abundance of Mordellidae among the canopy layers, while little variation was found for
Cerambycidae. The abundance, species diversity, and richness were generally greater in summer. The results showed distinct
species compositions in both families among layers. 相似文献