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991.
基于ZigBee无线传感器网络的森林环境监测系统 总被引:2,自引:0,他引:2
设计了一种基于ZigBee无线传感器网络的森林环境监测系统;描述了该系统的构成原理与整体结构,以及基于CC2430芯片的传感器节点和网关的硬件设计和系统软件工作流程.采用的星—簇首—路由的拓扑结构,具有低成本、易于部署、使用寿命长等优点. 相似文献
992.
石斑鱼是我国南方海水养殖的主要种类之一,而大部分石斑鱼种类均为暖水性鱼类,养殖水温要求在15℃以上,限制了石斑鱼在北方的发展。七带石斑鱼是唯一一种可以在较低温下生活,被人们称为“冷水石斑”,适合在北方养殖,如今已成为中、日、韩三国海水鱼类繁育研究的热点。由于七带石斑鱼人工繁殖和苗种培育过程中有许多制约条件,其人工繁育仍未达到稳定大批量生产的规模。主要问题有以下几个:①雄性亲鱼难获得,数量较少,限制了苗种的大量繁育;②初孵仔鱼的个体弱小、口径小,对开口饵料要求严格,适口饵料极少;③稚鱼期鱼苗互相残杀极其严重,出现大鱼吃小鱼的现象。此外,还有卵质不良,仔稚幼鱼疾病等难题。本文简要概述了国内外七带石斑鱼繁殖生物学与人工繁育研究进展情况,并对其养殖过程中出现的问题进行探讨和总结,为今后开展七带石斑鱼规模化人工养殖研究提供参考。 相似文献
993.
Frankliniella occidentalis was first recorded in Hungary in 1989. The pest has endangered the mass-rearing and distribution of the biological control agents Encarsia formosa and Phytoseiulus persimilis being conducted at the Hódmezövásárhely Institute. Different insecticide active ingredients were studied for elimination of the pest from experimental glasshouses and new methods for monitoring populations of the new thrips. The fungus Verticillium lecanii has been tested as an indirect control agent. 相似文献
994.
Ion-exchange and filter-paper columns were used in a separation of amino acids from an extract of Astragalus bisulcatus. Two amino acids were identified, S-methylcysteine and Se-methylselenocysteine. 相似文献
995.
2011年1月15日,由三仪集团主办的家禽疫病防控、健康和生态养殖研讨会在三仪集团二次创业主战场--江苏邳州隆重召开.这是三仪集团成立12年来首次组织召集大中型养殖(集团)公司共同探讨行业发展、倡导生态养殖.会议吸引了来自山东、河南、江苏和北京的部分大中型养殖(集团)公司总经理和技术总监共100多人. 相似文献
997.
MENG Yu-jiao LI Ning-fei ZHAI Chun-yan LIU Zheng-rong LI Xue DI Ting-ting ZHAO Jing-xia WANG Yan ZHANG Lu WANG Hong-yan LI Ping 《园艺学报》2018,34(8):1468-1476
AIM: To investigate and compare the effects of Yangxue (YX) decoction and Yangxue-Jiedu (YXJD) decoction on psoriasis-like mouse skin lesions. METHODS: BALB/c mice (n=50) were randomly divided into control group, model group, methotrexate (MTX) group, YX group and YXJD group (10 mice in each group). The psoriasis-like mouse model was induced by topical application of imiquimod cream on the back. The skin water/oil test pen was used to detect the water/oil content of the skin in the back of the mice. The pathological changes of the lesions were observed by HE staining and the thickness of the epidermis was measured. The immunohistochemical staining was used to observe the skin lesions, and the mRNA expression levels of interleukin (IL)-17, IL-23 and IL-1β in skin lesions were detected by real-time PCR. RESULTS: The skin lesions in YX, YXJD and MTX group were better than those in model group, with lower psoriasis area and severity index (PASI) score and skin thickness. The skin water/oil content in YXJD group was higher than that in model group (P<0.05). The expression of proliferating cell nuclear antigen (PCNA) and the positive expression of CD3+ T cells in the skin of YXJD group were lower than those in YX group, and the skin thickness was lower than that in YX group (P<0.05). The results of real-time PCR showed that relative mRNA expression of IL-17, IL-23 and IL-1β in YX group and YXJD group was lower than that in model group (P<0.05), and the relative mRNA expression of IL-1β in YXJD group was lower than that in YX group. Administration of YXJD decoction showed better therapeutic effect than MTX. CONCLUSION: YX decoction and YXJD decoction relieve imiquimod-induced skin lesions by reducing immune response. Meanwhile, the effect of YXJD decoction is better than that of YX decoction. 相似文献
998.
江苏省机械化植棉的可行性分析 总被引:1,自引:1,他引:1
本文分析了建国后江苏省植棉业的发展形势、纺织工业对原棉总量的需求变化以及我国棉花生产丰歉状况对世界原棉价格的影响。在深刻剖析近20年来江苏省棉花生产逐渐滑坡原因的基础上,提出变革棉花种植方式,改营养钵育苗移栽为麦(油)后直播,选用优质、高产、特早熟新品种,走机械化植棉之路。从常年大麦或油菜收获后至初霜期这一阶段≥10℃有效积温与新疆棉区的比较,结合已育成的优质、高产、特早熟棉花新品系大区试验结果,阐明了江苏省实现机械化植棉的可行性。调整农作物布局,将江苏省棉区逐步向秋季少雨的沿海、徐淮地区集中,形成优质、高产、高效植棉带。转变农业经营方式,通过土地的流转或有偿使用,实现麦(油)后直播棉花的大面积成片种植。根据农村经济的发展状况,提出江苏省机械化植棉分两步实施的发展战略。 相似文献
999.
AIM: To investigate the effects of 17β-estradiol (E2) on the maturation and immunologic function of dendritic cells from human peripheral blood. METHODS: Cultured DCs were treated with E2 at doses of 10-7 mol/L and 10-6 mol/L. The morphologic changes were observed under the scanning electronic microscope. The immunophenotype of DCs in control and treated groups was analyzed by flowcytometry. IL-12 production in culture supernatant was examined by ELISA assay. The capability of the stimulatory activity of the DCs on allogeneic T cells in mixed reaction was tested by incorporation of [3H]-TdR. RESULTS: Compared with control group, DCs cultured in the presence of E2 displayed less dendritic pseudopod, expressed low levels of MHC-II, CD40, CD80 and CD86, and exhibited weakly activity in stimulating the proliferation of allogeneic T cells and reduction of IL-12 production. CONCLUSION: E2 exerts a negative effect on the maturation and immunologic function of dendritic cells from human peripheral blood. 相似文献
1000.
Univ. Prof. Dr. rer. nat. Dipl. Geogr. Karl-Georg Bernhardt DI Marie-Louise Oschatz DIDr Daniel Laubhann Mathilde Stallegger Stefanie Rüscher DI Andreas Surböck 《Gesunde Pflanzen》2014,66(3):103-109
The project deals with the evaluation whether the conversion to organic farming leads to an increase of weed diversity. Additionally to the analysis of the above ground vegetation and the soil seedbank on the small permanent plots a mapping of the surrounding vegetation was conducted in 2012. The number of weed species varies highly over the years, but the inventory of species differs only slightly from the one found on the surrounding fields. The number of seeds per m² is highly correlated with the number of above ground weeds species. The crop has shown the highest influence on both. 相似文献