简介：TaijiquanisamartialartofthehighestorderisculturallyetchedintheChineseheritageandentrenchedinwushupulpfictionandkungfumovies.Thereinliestheenigma.Thegentleslow-motionpracticecannotbemoreremotefromthespeedandpowerofcombat.AndaddingtothemystiqueisthepropositionthatTaijiquan'skungfuprowessisnotdrawnfromthephysicalstrengthofthemusculaturebutfromsome"innerstrength"orNeijin.ThissacredbeliefwasdesecratedwhenafighterthrashedaselfproclaimedTaijiquangrandmasterignominiouslyin10secondsinanopenmatch.Taijiquanwasthenderidedasaboguscombatart.TheincidentshakesthefoundationofTaijiquanandputsintoquestionsmanyofitstoutedclaims,whichchallengesthescientificquestoftheart.ThepaperconfrontstheissuedirectlybystudyingthemanifestationofNeijinintheframeworkofsciencetoprovideascientificbasisfortheart.Ittranscribestheyin-yangmetaphysicsthatregulatesTaijiquantrainingintermsofthealignmentofmuscleactionstobalanceandtounifymomentum,whichdevelopsthecorestrengthofNeijinandtheunderlyinglife-forceQienergy.Fromthisflowsthekungfumarvels,whichlieinthelivelinessandagilityofNeijin'sresponseandintheforceensuingthatisoftherightvectorvalues,allessentialinthefluidityofcombatapplication.ThemartialaspectofTaijiquanprovidesaconcreterepresentationofNeijin,whichgivesanexperientialinsightintothemultifacetedconceptofQi,andinturnapathwaytotheexplorationofQiinphysiologyandthusinQienergymedicine.

简介：通过对20世纪80年代以来具有代表性的华北夏谷区审(鉴)定的20个主栽谷子品种进行SSR标记多态性分析,研究了华北地区育成谷子品种的遗传多样性。49对引物在20个谷子品种中扩增出具有多态性的条带,共检测出142个等位变异,平均每个位点检测出的等位变异数为2.96个。标记位点多态性信息含量(PIC)变幅为0.0904~0.6896,平均为0.4168。20份材料间的遗传距离变幅为0.0173~0.9000,聚类分析将其分成3个类群,其中谷丰1号自成一类,表明谷丰1号的遗传距离较其他品种大。不同年代谷子品种间遗传距离分析结果显示,各年代品种之间的平均遗传距离由大到小依次是1980s>1990s>2000s>2010s,表明随着年代的递进育成品种的遗传差异减小,亲缘关系增近。

简介：【目的】为持续有效防控白背飞虱,研究云南东部白背飞虱种群对常用5种杀虫剂的敏感性及药剂的田间防治效果。【方法】采用室内稻茎浸渍法测定白背飞虱种群对5种杀虫剂的敏感性,同期通过田间小区试验评价5种杀虫剂对白背飞虱种群的防治效果。【结果】与敏感种群比较,噻虫嗪、噻嗪酮、吡虫啉、吡蚜酮和毒死蜱对滇东白背飞虱种群的LC50分别为0.208、0.459、0.608、3.108、1.256mg·L-1,抗性倍数分别为2.2、10.4、5.6、6.5、5.3倍;白背飞虱对噻虫嗪无抗性,对吡虫啉、吡蚜酮和毒死蜱为低水平抗性,对噻嗪酮为中等水平抗性;5种杀虫剂药后1、5和10d对白背飞虱种群的田间防控效果均有显著差异。除了吡蚜酮外,其他药剂的防效均在80%以上,其中以吡虫啉和噻嗪酮的持续期较长,药后10d仍在90%以上;噻虫嗪和吡虫啉药后1和5d的防效达90%以上;吡蚜酮药效在供试药剂中防效最低,在64.88%~77.82%之间。【结论】滇东师宗白背飞虱种群对噻嗪酮为中等水平抗性,对吡虫啉、吡蚜酮和毒死蜱均为低水平抗性,对噻虫嗪无抗性,田间防控效果以吡虫啉和噻嗪酮为最好。建议滇东稻区可以使用吡虫啉和噻嗪酮药剂防控白背飞虱,注意控制吡蚜酮的使用次数与用量。