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南平市海鲜菇工厂化栽培模式 总被引:3,自引:0,他引:3
鉴于南平市丰富的自然气候资源和农业资源条件,海鲜菇工厂化栽培模式得到快速发展并取得显著效益。该文总结出一套高产、优质、高效的工厂化栽培技术模式。 相似文献
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Tamas D. Ambrisko Arnon Gal Jesus N. Sarol Ashley Mitek Christina Braun 《Veterinary anaesthesia and analgesia》2021,48(2):205-212
ObjectiveTo evaluate the influence of reservoir bag types, volumes and previous use on the peak pressures (Pmax) and the times to develop 30 cmH2O pressure (P30) within a nonrebreathing system with a closed adjustable pressure-limiting (APL) valve.Study designIn vitro study using three-way factorial design with repeated measure on one factor.SubjectsA total of 75 new anesthesia reservoir bags (five types, three volumes, five bags from each type × volume). The bag types were reusable latex (RL), disposable latex (DL) and three disposable neoprene (DN-1, DN-2 and DN-3).MethodsEach bag was tested three times (treatments): new, after prestretching and 1 week later. The bags were attached to a Bain system and anesthesia machine with closed APL valve and patient port with O2 flow 2 L minute–1 until Pmax was reached. The Pmax and time to reach P30 values were determined from recorded pressure traces. General linear mixed model analysis was used to examine the effects of bag type, volume and treatment. One-sided 95% upper prediction limits of Pmax were calculated to test the null hypothesis that predicted Pmax of new bags would be ≥ 50 cmH2O for each factor combination.ResultsRL bags were the least and DN-3 bags were the most compliant. Prestretching increased compliance in all bag types. Smaller bags of RL, DL and DN-1 were less compliant than larger ones. The predicted Pmax values were < 50 cmH2O only for DN-3 bags after prestretching. The time to reach P30 was critically low when using 0.5 L bags (median 17 seconds).Conclusions and clinical relevanceTo minimize the risk of barotrauma, highly compliant reservoir bags (e.g. DN-3) are recommended and reusable bags should be avoided. Bags should be prestretched before first use, 0.5 L bags should be avoided and fresh gas flow minimized. 相似文献
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In vitro rumen fermentation and digestibility of buffaloes as influenced by grape pomace powder and urea treated rice straw supplementation
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This study aimed to investigate the effect of grape pomace powder levels and roughage sources on gas kinetics, digestibility and fermentation of swamp buffaloes by using in vitro techniques. The experimental design was a 2 × 4 factorial arrangement in a completely randomized design. Factor A was two sources of roughage (untreated rice straw, RS, and 3% urea treated rice straw, UTRS) and factor B was four levels of grape pomace powder (GPP) supplementation (0, 2, 4, 6% of substrate) on a dry matter basis. Results revealed that GPP supplementation at 2, 4 and 6% of substrate influenced gas kinetics. Cumulative gas production tended to be lower in the supplemented group. In vitro true digestibility was higher in the GPP supplementation at 2% with UTRS while microbial mass was higher in the supplemented groups. Supplementation of GPP significantly increased the total volatile fatty acids, especially propionate. Calculated methane production was subsequently decreased in the supplemented groups. Bacterial population was higher while protozoal population was lower by GPP supplementation. It could be concluded that supplementation of GPP at 2% of the substrate with UTRS improved in vitro true digestibility, rumen fermentation end‐products as well as reducing methane production. 相似文献
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为室内大量繁殖中华卵索线虫Ovomermis sinensis,采用个体由大到小的斜纹夜蛾Spodoptera litura、棉铃虫Helicoverpa armigera和黏虫Mythimna separata作为宿主,测定被中华卵索线虫寄生后3种宿主的体长和体重,研究宿主种类对中华卵索线虫有效率、雌雄比和体长的影响以及寄生强度对线虫雌雄比的影响。结果显示,被中华卵索线虫寄生后,斜纹夜蛾、棉铃虫和黏虫生长减缓。在相同感染比例下(除宿主与线虫比为1∶15外),3种宿主的线虫有效率之间差异不显著。当寄生强度为5时,3种宿主体内脱出的中华卵索线虫均为雌线虫;当寄生强度从10增到40时,斜纹夜蛾、棉铃虫和黏虫所脱出的雌性比分别由100.0%、90.0%、83.9%降为0;相同寄生强度下,从斜纹夜蛾体内脱出的雌性比显著高于从棉铃虫与黏虫体内脱出的雌性比。斜纹夜蛾、棉铃虫和黏虫体内脱出雌线虫和雄线虫平均体长分别为14.8、13.8、12.8 cm和8.0、7.5和7.5 cm。当中华卵索线虫与宿主按照比例20∶1~25∶1侵染斜纹夜蛾、按照15∶1侵染棉铃虫和黏虫时,能获得线虫最适雌雄比(1∶1... 相似文献
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The mechanism of MIPv4 regional registration and the low latency handoff protocols are introduced. Ways and procedure of pre-registration handoff and post-registration handoff are discussed also. The authors analyze the performance of the low latency handoff protocols combined with low latency handoffs over a wireless access based on IEEE 802. 11 standard in a tree-like network topology. The performance of pre-registration and post-registration scheme is given by simulation. 相似文献