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951.
The aim of this study was to assess the effects of climate change on green and blue water use with temporal change in the transplanting and growing season for paddy fields in South Korea using the representative concentration pathway (RCP) 4.5 and 8.5 scenarios in 2025 (2011–2040), 2055 (2041–2070), and 2085 (2071–2100). The optimal transplant date determined by an accumulated temperature analysis, between 27 April and 21 May in 1995, was delayed until 29 June in 2085, and the average growing period was decreased by about 20 days in 2085. Changes in the transplanting season and growing period could influence the efficiency of future green water use and blue water savings. Approximately 810.5 Mm3 of green water was available during the 1995 transplanting season, but the predicted use of green water was 1524.7 Mm3 in future for the optimal transplanting season. In addition, 923.0 Mm3 of blue water savings can be expected in 2025. This study showed that appropriate change of transplanting season could mitigate the water requirements in paddy fields by optimizing phenology, improving green water efficiency, and blue water savings. 相似文献
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954.
中国城镇化进程的快速推进,使得各种建设活动对土地资源的需求日益增加,引发一系列生态环境问题,特别是在生态脆弱区,土地资源不合理的开发利用加剧了区域生态安全风险。因此,为探究区域生态安全格局优化的途径方法,保障区域生态安全和土地资源合理利用,该研究通过解译判读怀来县1993年、2003年和2013年3期遥感影像,运用土地利用变化信息图谱及构建建设用地和生态用地竞争优势模型,分析了怀来县土地利用变化热点区域及建设用地与生态用地竞争优势分布区,划分了建设用地与生态用地优势分布临界线,同时,基于景观生态学理论,构建了怀来县综合生态安全格局,并将建设用地与生态用地竞争优势分布区应用于生态安全格局优化。结果表明:怀来县综合生态安全格局面积为1 470.59 km2,占怀来县总面积的82.51%,基本安全格局分布在临界线外围,满意安全格局外围主要沿临界线分布、理想安全格局主要分布在临界线内部。基本生态安全格局受到建设用地扩张的压力相对较小,满意生态安全格局主要位于生态优势区,在一定程度可以起到对建设用地扩张的限制作用,作为怀来县重要的生态缓冲区,理想安全格局受到建设用地扩张的压力较大,其内部应注重生态廊道网络建设,引导自然斑块以廊道或小型斑块的形式分散地融入建设用地中。研究方法和结果可以为区域生态规划和城乡布局等提供决策参考。 相似文献
955.
Deep eutectic solvent, urea-choline chloride (URC), was used to control surface of poly(ethylene terephthalate) (PET) fabric under microwave irradiation with or without sodium hydroxide (NaOH) for hydrophilic-hydrophobic properties. Wicking and contact angle evaluations indicated that the URC-treated PET fabric drastically changed its surface characteristics from highly hydrophobic to highly hydrophilic (or vice versa) by carefully adjusting alkali concentration and microwave irradiation time. For instance, an instant wicking was achieved on URC-treated PET with 1 % NaOH at 60 s of microwave irradiation, whereas highly hydrophobic PET surface with 2600 s wicking time and 135.6 ° contact angle was acquired by adding 5 % NaOH at the same microwave irradiation. Methylene Blue staining and FTIR analyses suggested that a minimal hydrolysis occurred through URC-treatment with NaOH under microwave irradiation and hydrophilicity was mainly achieved by physical disruption of the fiber. The treated fabrics were further analyzed by DSC, TGA, and SEM. Therefore, a rapid control of hydrophilic-hydrophobic surface of PET fabric was achieved with a little side reaction by using environmentally-benign, biodegradable URC deep eutectic solvent. 相似文献
956.
The antibacterial activity, selection of Escherichia coli (E. coli) mutants and mechanisms of fluoroquinolone resistance were investigated by integrating the minimum inhibitory concentration (MIC), mutant prevention concentration (MPC) and in vitro dynamic model approaches. Difloxacin and orbifloxacin, for which the above information has been scarce, were used. A range of area under curve over a 24h interval (AUC(24h))/MIC ratios and selected E. coli strains were investigated using the dynamic models. Continuous incubation for three days in the presence of difloxacin or orbifloxacin resulted in losses in E. coli susceptibility. An AUC(24h)/MIC (AUC(24h)/MPC)-dependent fluoroquinolone activity and selection of E. coli mutants was confirmed. Maximum losses in susceptibility occurred at AUC(24h)/MIC ratios of 54 (orbifloxacin) and 57.3 (difloxacin). AUC(24h)/MIC ratios of 169.8 (orbifloxacin) and 199.5 (difloxacin) were estimated to be protective against the selection of E. coli mutants, and the corresponding ratios based on AUC(24h)/MPC predictions were 34 (orbifloxacin) and 36.3 (difloxacin). When integrating our in vitro data with pharmacokinetic data in dogs, the conventional clinical doses of both drugs were found to be inadequate to attain the above protective values for 90% of the mutant subpopulation (AUC(24h)/MPC(90)). Both target mutations, esp. at codon 83 (Ser to Leu) of gyrA, and overexpression of efflux pumps contributed to resistance development, with mutants also showing decreased susceptibility to enrofloxacin and marbofloxacin. Additional studies would determine the role of mutations found outside the QRDR, at codon 24 of gyrA, and at codon 116 of parC, and establish the significance of these observations in vivo. 相似文献
957.
We investigated the effect of caffeoylserotonin (CaS) on THP-1 monocyte migration and adhesion to fibronectin in response to MCP-1. CaS decreased monocyte adhesion and migration induced by MCP-1, together with CCR2 expression and α5β1 integrin, and activated β1 integrin expression on the cell surface. CaS also inhibited FAK and Akt phosphorylation. We found that CaS had anti-inflammatory activity based on inhibition of adhesion and migration via inhibition of the integrin β1/FAK/Akt signalling pathway. Thus, the inhibitory effects of CaS on monocyte function may support the future development of this compound as a potential treatment for inflammation-dependent diseases. 相似文献
958.
Rahman MM Uyangaa E Han YW Kim SB Kim JH Choi JY Eo SK 《Veterinary microbiology》2012,157(3-4):448-455
The combined use of cytokines has shown synergistic and/or additive effects in controlling several viral infections of livestock animals. However, little is known concerning the practical use of chicken cytokine combinations to control avian diseases. Here, we investigated the antiviral efficacy of oral co-administration of chicken interferon-α (chIFN-α) and chicken interleukin-18 (chIL-18) using attenuated Salmonella enterica serovar Typhimurium in chickens infected with avian influenza virus (AIV) H9N2. Our results demonstrate that oral co-administration of S. enterica serovar Typhimurium expressing chIFN-α and chIL-18 produced a greater alleviation of clinical signs caused by respiratory infection with AIV H9N2 in chickens, when compared to administration of S. enterica serovar Typhimurium expressing either chIFN-α or chIL-18 alone. Mortality, clinical symptom severity, and feed and water intake were used to access treatment effectiveness. This enhancement of antiviral immunity was further confirmed by evidence of reduced rectal shedding and decreased replication of AIV H9N2 in several different tissues of challenged chickens including trachea, lung, cecal tonsil, and brain. Furthermore, oral co-administration of chIFN-α and chIL-18 more efficiently modulated the immune responses of chickens against AIV H9N2 by enhancing both humoral and Th1-biased cell-mediated immunity, compared to single administration of either construct. Therefore, our results suggest that the combined administration of two chicken cytokines, chIFN-α and chIL-18, using attenuated S. enterica serovar Typhimurium as an oral carrier, provides an effective means for controlling respiratory disease caused by AIV H9N2 infection. 相似文献
959.
Kim HS Lee JY Jeong EJ Yang CJ Hyun SH Shin T Hwang WS 《The Journal of reproduction and development》2012,58(1):132-139
To artificially activate embryos in somatic cell nuclear transfer (SCNT), chemical treatment with ionomycin has been used to induce transient levels of Ca(2+) and initiate reprogramming of embryos. Ca(2+) oscillation occurs naturally several times after fertilization (several times with 15- to 30-min intervals). This indicates how essential additional Ca(2+) influx is for successful reprogramming of embryos. Hence, in this report, the experimental design was aimed at improving the developmental efficiency of cloned embryos by repetitive Ca(2+) transients rather than the commonly used ionomycin treatment (4 min). To determine optimal Ca(2+) inflow conditions, we performed three different repetitive ionomycin (10 μM) treatments in reconstructed embryos: Group 1 (4-min ionomycin treatment, once), Group 2 (30-sec treatment, 4 times, 15-min intervals) and Group 3 (1-min treatment, 4 times, 15-min intervals). Pronuclear formation rates were checked to assess the effects of repetitive ionomycin treatment on reprogramming of cloned embryos. Cleavage rates were investigated on day 2, and the formation rates of blastocysts (BLs) were examined on day 7 to demonstrate the positive effect of repeated ionomycin treatment. In Group 3, a significant increase in BL formation was observed [47/200 (23.50%), 44/197 (22.33%) and 69/195 (35.38%) in Groups 1, 2 and 3, respectively]. Culturing embryos with different ionomycin treatments caused no significant difference among the groups in terms of the total cell number of BLs (164.3, 158.5 and 145.1, respectively). Additionally, expression of the anti-apoptotic Bcl-2 gene and MnSOD increased significantly in Group 3, whereas the expression of the pro-apoptotic Bax decreased statistically. In conclusion, the present study demonstrated that repeated ionomycin treatment is an improved activation method that can increase the developmental competence of SCNT embryos by decreasing the incidence of apoptosis. 相似文献
960.
Min BR Solaiman S Gurung N Behrends J Eun JS Taha E Rose J 《Journal of animal science》2012,90(10):3556-3567
Twenty-two Kiko crossbred male goats (Capra hircus; initial BW = 27.5 ± 1.04 kg) were used in a randomized complete block design to determine the effects of feeding pine bark (PB; Pinus taeda L.) on animal performance, rumen fermentation, blood parameters, fecal egg counts (FEC), and carcass characteristics in goats. Experimental treatments included the control diet [0% PB plus 30% wheat straw (WS)], 15% PB plus 15% WS, and 30% PB plus 0% WS (on as-fed basis), where PB replaced WS. Freshly air-dried PB and WS were finely (1.5 to 3.0 mm) ground and incorporated in the grain mixes. Experimental diets provided a total of 1.9, 16.3, and 32 g of condense tannins (CT)/kg DM in 0%, 15%, and 30% PB diets, respectively. The grain mixes were fed daily at 85% of the feed offered, with remaining 15% consisting of Bermuda grass hay (Cynodon dactylon). Animals were fed once a day at 0800 h, and feed offered and refused was monitored for an 83-d performance period. Rumen and blood samples were collected at d 0, 50, and 80 of the study. Carcass traits were assessed after slaughter at the end of performance period. There was no difference in initial BW, hay, and total NDF intake among treatments; however, final BW (P = 0.06), ADG (P < 0.01), grain mix intake (P < 0.001), total DMI (P < 0.001), and G:F (P < 0.04) increased linearly as the PB increased in the diets. Rumen ammonia N, acetate, isovalerate and acetate-to-propionate ratio were reduced linearly (P < 0.05). There was no difference in carcass traits except cold carcass weight (P = 0.06), which tended to increase linearly in goats fed 15% and 30% PB. Breast, sirloin, trim trait, liver, and hide weight increased (linear; P < 0.01) with addition of PB. Blood basophils, alanine transaminase, aspartate aminotransferase, albumin, Na, and Cl concentrations decreased (linear; P < 0.02 to 0.01) as PB supplementation increased. Supplementation of PB reduced (linear; P < 0.01) average FEC. Addition of PB in the diets improved performance, reduced FEC, and favorably modified rumen fermentation. 相似文献