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101.
Water shortages during the dry season threaten sustainable agricultural production in Nganjuk District, East Java, Indonesia. To mitigate this problem, farmers adopted conjunctive use of surface water and groundwater, but the sustainability of this practice has not been investigated. This study temporally and spatially assessed water allocation in Nganjuk District when conjunctive irrigation was used. In particular, the land cover, water balance, and irrigation well density (IWD) were analyzed using time series GIS and remote sensing data to obtain their temporal and spatial distributions. First, the land cover was analyzed to determine cropping intensity, and the water balance was analyzed temporally and spatially. IWD was introduced to facilitate the water balance analysis. Second, the land cover, water balance, and IWD results were overlaid. Third, the effectiveness of the IWD method, the magnitude of water shortages, and the sustainability of groundwater resources were considered. Temporal and spatial water shortages in irrigation blocks were observed during the dry season. The change of storage showed a surplus during the wet and early dry seasons and a shortage during the late dry season. The annual water balances indicated that the southern part had a surplus, and the northern part experienced water shortages, especially downstream of the Widas River. Conjunctive use during the late dry season was predominant and concentrated in the southern part (83% of southern blocks). IWD was appropriate for examining groundwater use trends and was effective for expressing average withdrawal data (R 2 = 0.87). 相似文献
102.
MJ Siemieniuch E Jursza MP Kowalewski M Majewska DJ Skarzynski 《Reproduction in domestic animals》2013,48(1):72-78
Sex steroids in synergy with prostaglandins (PG) are involved in the regulation of cyclic ovarian function. In this study, we investigated the mRNA expression of three genes involved in arachidonic acid (AA) metabolism and hence PG production in domestic cats: PG‐endoperoxide synthase (PTGS2), PGF2α synthase (PGFS) and PGE2 synthase (PGES). Feline endometria (n = 16) were collected at oestrus and mid and late phases of pseudopregnancy. In addition, the effects of E2 and/or P4 on PG secretion and gene expression on endometrial explants were studied in an in vitro culture system. Expression levels of all examined genes were up‐regulated at the mid phase of pseudopregnancy. The effects of E2 and/or P4 treatment on both PG secretion and expression of the genes were observed after 12 h of culture. Expression of PGES was significantly up‐regulated by E2 plus P4 at oestrus and the mid phase of pseudopregnancy and was also up‐regulated by a single treatment with P4 at late pseudopregnancy (p < 0.05). Simultaneous incubation with E2 and P4 up‐regulated PTGS2 gene expression at oestrus and mid‐luteal phase (p < 0.05). Progesterone plus E2 significantly increased PGE2 secretion at oestrus and the mid phase of pseudopregnancy. However, treatment with E2 and/or P4 affected neither PGF2α secretion nor PGFS expression at any phase after 12 h of culture. The overall findings indicate that genes involved in PG synthesis are up‐regulated at the mid phase of pseudopregnancy. An increase in PGE2 secretion and up‐regulation of PGES and PTGS2 are the main responses of the endometrium to treatment with E2 and P4 at oestrus and the mid phase of pseudopregnancy in the cat. These data support the hypothesis that ovarian sex steroids via endometrial PGE2 are involved in endocrine homoeostasis, especially at oestrus and the mid, but not the late, phase of pseudopregnancy in cats. 相似文献
103.
Koji Yamane Ranee C. Mabesa-Telosa Ryosuke Tajima Nino P. M. C. Banayo Yoichiro Kato 《植物养料与土壤学杂志》2019,182(1):28-30
Simple tools for diagnosing crop nutritional status are in great demand by agricultural extension staff, particularly in low‐fertility environments. We developed the first practical method for in situ diagnosis of phosphorus (P) nutrition in field‐grown cereal crops by using a handheld colorimeter. The concentration of P in extracts from fresh leaves of lowland rice grown under various P availabilities was closely correlated with that of oven‐dried leaves measured with the standard molybdenum‐blue method in the laboratory, over a range of values from 0.319 to 1.420 mg P g ?1 DW (r = 0.885**, n = 14). It takes only 3–5 min to estimate the P concentration of plant samples using the new technique. Although not as accurate as the laboratory method, the new method can easily detect P deficiency of rice in the field (and possibly other cereal crops) without requiring costly, off‐site equipment. Thus, extension staff and agronomists can easily adopt this technique. 相似文献
104.
Shimizu E Kato H Nakagawa Y Kodama T Futo S Minegishi Y Watanabe T Akiyama H Teshima R Furui S Hino A Kitta K 《Journal of agricultural and food chemistry》2008,56(14):5521-5527
A novel type of quantitative competitive polymerase chain reaction (QC-PCR) system for the detection and quantification of the Roundup Ready soybean (RRS) was developed. This system was designed based on the advantage of a fully validated real-time PCR method used for the quantification of RRS in Japan. A plasmid was constructed as a competitor plasmid for the detection and quantification of genetically modified soy, RRS. The plasmid contained the construct-specific sequence of RRS and the taxon-specific sequence of lectin1 (Le1), and both had 21 bp oligonucleotide insertion in the sequences. The plasmid DNA was used as a reference molecule instead of ground seeds, which enabled us to precisely and stably adjust the copy number of targets. The present study demonstrated that the novel plasmid-based QC-PCR method could be a simple and feasible alternative to the real-time PCR method used for the quantification of genetically modified organism contents. 相似文献
105.
Turbid water induces refuge behaviour of a commercially important ayu: A field experiment for interstream movement using multiple artificial streams
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Terutaka Mori Yasumitsu Kato Tetsuya Takagi Yukio Onoda Yuichi Kayaba 《Ecology of Freshwater Fish》2018,27(4):1015-1022
Riverine systems are inherently dendritic in nature, and turbid water may not necessarily flow equally throughout an entire catchment. Tributaries have the potential to serve as refugia from temporarily turbid water in the main stem. As ayu (Plecoglossus altivelis) are one of the important species for the inland fisheries industry and recreational fishing, their behaviour in a branched river network is a primary concern. We released ayu with radio‐transmitting tags into two experimental streams that joined at a downstream pool. Turbid water was released into one of the streams, and we identified whether avoidance movement of ayu between the two experimental streams was triggered by flowing turbid water. The suspended solid concentration elevated rapidly after adding the turbid water and was maintained at more than 400 mg/L for 3 hr. Avoidance movement of ayu was triggered when the suspended solid concentration exceeded approximately 200 mg/L. Then, most ayu moved from the turbid stream to the nonturbid one, leading to a difference in ayu density between the two streams. Therefore, we demonstrated that turbid water induced interstream movement of a commercially important ayu as refuge behaviour, suggesting that river connectivity is important for the persistence of the ayu. 相似文献
106.
107.
Terayama Y Kato H Gomez EA Uezato H Calvopiña M Iwata H Hashiguchi Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(9):907-913
Surveillance of the distribution of sand fly species is important for prediction of the risk and expansion of Leishmania infection in endemic and surrounding areas. In the present study, a simple and reliable method of typing New World Lutzomyia species circulating in endemic areas in Ecuador was established by using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) technique. PCR-RFLP of 18S ribosomal RNA (rRNA) genes with the restriction enzyme AfaI and subsequently HinfI successfully identified seven sand fly species in nine endemic areas in Ecuador. Although intraspecific genetic-diversity affecting the RFLP-patterns was detected in a species, the patterns were species specific. The method promises to be a powerful tool for the classification of New World Lutzomyia species. 相似文献
108.
MJ Siemieniuch 《Reproduction in domestic animals》2008,43(4):473-476
Apoptosis (programmed cell death) could be considered as a physiological process that takes part in a healthy organism, which helps to maintain organism homeostasis. The visible deterioration of semen quality and the number of germ cells is accompanied by a seasonal decrease of the reproductive activity in some species. This post-effect cascade is caused by apoptosis, which is the primary mechanism responsible for the elimination of germ cells during spermatogenesis. The aim of our study was to assess apoptotic changes in the epithelium germinativum in cat testes at different ages. One hundred and two pairs of testes were obtained from domestic cats aged between 4 months and 10 years. The paraffin-embedded tissue sections were labelled using the Oncogene and Calbiochem Research Products DNA Fragmentation Detection Kit (Cat# QIA21; Darmstadt, Germany), which allows the recognition of apoptotic nuclei in tissue sections with Fragment End Labelling (FragELTM ) of DNA. The activity of apoptotic processes in cat testes collected from the spring-summer period compared with the autumn-winter season revealed that, 59.42% and 51.51%, respectively, males testes were characterized by insignificant changes. The obtained data revealed a distinctive apoptotic changes in the young animal testes before spermatogenesis onset. An intensification of programmed death cells in the epithelium germinativum in the elder cats (between 3–6 and 6–10 years) was not observed. Apoptotic changes slightly intensified in cats aged between 12 and 36 months. 相似文献
109.
Accelerator mass spectrometer dating of an assemblage of fibrous and leather footwear from Arnold Research Cave in central Missouri documents a long sequence of shoe construction by prehistoric Midwestern peoples, beginning perhaps as early as 8300 calendar years before the present (cal years B.P.). An earlier fibrous sandal form dates from 8325 to 7675 cal years B.P., and later fibrous or leather slip-ons span the period from 5575 to 1070 cal years B.P. The assemblage adds to a growing picture of the highly varied nature of prehistoric footwear production in the United States throughout the Holocene. 相似文献
110.
Genesis and evolution of the 1997-98 El Nino 总被引:4,自引:0,他引:4
MJ McPhaden 《Science (New York, N.Y.)》1999,283(5404):950-954
The 1997-98 El Nino was, by some measures, the strongest on record, with major climatic impacts felt around the world. A newly completed tropical Pacific atmosphere-ocean observing system documented this El Nino from its rapid onset to its sudden demise in greater detail than was ever before possible. The unprecedented measurements challenge existing theories about El Nino-related climate swings and suggest why climate forecast models underpredicted the strength of the El Nino before its onset. 相似文献