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71.
随着机器人足球的发展,机器人防守和进攻的队形对于比赛显得尤为重要。为了加强机器人足球比赛中的防守和进攻,文章通过分析足球在不同区域时防守队形的选择、防守与进攻的队形转换、以及在极端情况下剩余机器人的有效利用等几个问题,研究和设计机器人防守和进攻队形转换的算法和策略。机器人队形的选择采用人性化的方法,大大提高了队形的形成速度,在极端状态下也做出相应的策略来加强进攻。通过实验表明,该策略增加了防守和进攻的效率,提高了进球的几率。  相似文献   
72.
添加中草药对饲料蛋白质消化率的影响   总被引:1,自引:0,他引:1  
试验采用体外消化法研究添加不同剂量的两种中草药对饲料蛋白质消化率的影响.选用陈皮、山楂两种中草药,然后在体外环境下模拟猪胃肠道消化环境进行测定.结果表明:(1)添加中草药陈皮A组(0.5%)和C组(1%)的消化残渣蛋白质质量和粗蛋白质消化率与对照组相比差异极显著(P<0.01),而B组(0.75%)与对照组相比差异显著(P<0.05).(2)添加中草药山楂D组(0.5%)、E组(0.75%)、F组(1%)三个组的消化残渣蛋白质质量和粗蛋白质消化率与对照组相比差异极显著(P<0.01).(3)山楂的效果明显好于陈皮,且山楂添加量为0.75%时最好.  相似文献   
73.
74.
闽东南天然降雨雨滴特征的研究   总被引:1,自引:0,他引:1  
该文在实测滴谱资料的基础上建立了闽东南地区雨滴大小分布函数。F=1-exp[-(d/3.58I0.28)5.19I0.11]并导出了雨滴中数直径、动能与雨强的关系为D50=3.34I0.29和E=36.04I0.29。笔者认为两型对雨滴特征是有影响的。  相似文献   
75.
Glutathione (GSH) concentrations of oocytes are considered as an important marker of the cytoplasmic maturation. The present study was designed to compare GSH concentrations of in vivo and in vitro matured canine oocytes. In vivo matured oocytes were collected 72 hr after ovulation by flushing fallopian tubes after laparotomy. Ovaries were collected from bitches with different reproductive stages, and collected oocytes were divided into 2 groups according to the size viz. < 120 microm and > 120 microm in diameter and cultured for 72 hr in Tissue Culture Medium-199 supplemented with 10% FBS, 2.2 mg/ml sodium bicarbonate, 2.0 microg/ml estrogen, 0.5 microg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin-streptomycin solution in the presence or absence of 50 microM beta-mercaptoethanol. GSH concentrations were determined by the dithionitrobenzoic acid-glutathione disulfide (DTNB-GSSG) reductase recycling assay. GSH concentrations of immature canine oocytes were 2.9 and 3.8, 3.5 and 6.8, and 3.1 and 6.5 pM/oocyte for < 120 microm and > 120 microm in diameter oocyte groups at anestrous, follicular and luteal stage, respectively (P<0.05). In vivo matured oocytes had significantly higher GSH concentrations compared with in vitro matured oocytes. The GSH content was 19.2 pM/oocyte for in vivo matured oocytes, while 4.1 to 8.1 and 5.7 to 13.2 pM/oocyte for in vitro matured oocytes cultured in the absence or presence of beta-mercaptoethanol, respectively (P<0.05). Presence of beta-mercaptoethanol increased GSH synthesis in canine oocytes cultured in vitro, and oocytes collected from follicular and luteal stage was superior to anestrus oocytes.  相似文献   
76.
77.
本试验开展了青藤扦插繁殖试验,通过扦插季节、植物生长调节剂、遮阳对比试验,总结出了青藤的扦插繁殖技术,既可以解决藤编原料问题,同时又能达到保护野生植物资源的目的。  相似文献   
78.
AIM:To investigate the effect of 17β-estradiol (E2) on myocardial hypertrophy induced by endothelin-1(ET-1) and the related mechanism. METHODS:Myocardial cells from neonate rats were cultured in vitro and myocardial hypertrophy model was established with ET-1.The effects of 17β-estradiol on myocardial hypertrophy were observed. The role of ERK1/2 in the effects of 17β-estradiol was also detected. RESULTS:Compared with control group,ET-1 increased cell protein content,cell surface area and [3H]-Leucine [3H]-Leu) incorporation. Pretreatment with E2 for 24 h could inhibit the increase in cell protein content,cell surface area and [3H]-Leu incorporation induced by ET-1.ET-1 significantly stimulated ERK1/2 activity,which was prevented by pretreatment with E2.Tamoxifen,estradiol receptor antagonist,partially inhibited the effect of E2. The ability of ET-1 to stimulate [3H]-Leu incorporation was significantly blocked by PD98059,which could enhance the inhibitory effect of E2 on the increase of [3H]-Leu incorporation in cardiomyocytes induced by ET-1.CONCLUSION:E2 can inhibit cardiomyocyte hypertrophy induced by ET-1. This effect is mediated by estrogen receptor. ERK1/2 signal pathway is closely correlated with the inhibitory effect of E2 on cardiomyocyte hypertrophy induced by ET-1.  相似文献   
79.
AIM:To investigate the effects of the juice of fructus hippophae(JFH) on thrombocytopenia in rats.METHODS:Forty-eight wistar rats were divided into control group, model group, Yixuesheng-Jiaonang (YSJN) group and JFH group. Rats were injected intraperitoneally with cyclophosphamide (CTX, 30 mg/kg) or saline once a day for 3 days. And then, Saline, YSJN or JFH was administered (ig) once a day for 11 days. On the second, fouth, sixth and eighth day, the thrombocyte were counted, the mean platelet volume (MPV) and PDW were examined. On the eighth day, the cAMP, cGMP in platelets and platelet aggregation function were also examined.RESULTS:JFH could shorten the time of blood coagulation, increase the count of platelet, and enhance the platelet aggregation function. The experiment also showed that the JFH could decrease cGMP content in platelet.CONCLUSION:JFH could enhance blood coagulation and quality of platelet and prevent thrombocytopenia induced by cyclophosphamide in rats.  相似文献   
80.
A field experiment was conducted to study the effects of combination of straw incorporation and water management on fluxes of CH4, N2O and soil heterotrophic respiration (Rh) in a paddy field in subtropical central China by using a static opaque chamber/gas chromatography method. Four treatments were set up: two rice straw incorporation rates at 0 (S1) and 6 (S2) t ha?1 combined with two water managements of intermittent irrigation (W1, with mid-season drainage) and continuous flooding (W2, without mid-season drainage). The cumulative seasonal CH4 emissions for the treatments of S1W2, S2W1 and S2W2 increased significantly by 1.84, 5.47 and 6.63 times, respectively, while seasonal N2O emissions decreased by 0.67, 0.29 and 1.21 times, respectively, as compared to S1W1 treatment. The significant increase in the cumulative Rh for the treatments S1W1, S2W1 and S2W2 were 0.54, 1.35 and 0.52 times, respectively, in comparison with S1W2. On a seasonal basis, both the CO2-equivalents (CO2e) and yield-scaled CO2e (GHGI) of CH4 and N2O emissions increased with straw incorporation and continuous flooding, following the order: S2W2>S2W1>S1W2>S1W1. Thus, the practices of in season straw incorporation should be discouraged, while mid-season drainage is recommended in paddy rice production from a point view of reducing greenhouse gas emissions.  相似文献   
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