科创中国

Conservation?of?endangered?sympatric?species?must?be?carefully?executed?to?ensure?that?the?protection?of?one?species?does?not?negatively?impact?the?survival?of?another.?Critically?endangered?Pecos?gambusia?Gambusia?nobilis?and?Leon?Springs?pupfish?Cyprinodon?bovinus,?which?are?endemic?to?a?threatened?desert?spring?habitat,?exemplify?one?such?scenario.?Recently,?this?habitat?has?been?expanded,?and?captively?bred?C.?bovinus?were?released?to?repopulate?an?area?historically?known?to?contain?this?species.?A?previous?study?suggested?that?G.?nobilis?are?detrimental?to?C.?bovinus?populations,?due?to?their?tendency?to?congregate?near?spawning?pairs?and?feed?on?their?eggs.?Whether?G.?nobilis?are?attracted?to?territorial?C.?bovinus,?regardless?of?spawning?behavior,?remains?unclear.?To?determine?this,?the?number?of?G.?nobilis?in?occupied?and?unoccupied?breeding?territories?of?both?wild?and?captively?bred?C.?bovinus?was?measured.?Gambusia?nobilis?densities?were?similar?between?unoccupied?and?occupied?territorial?sites,?suggesting?that?they?do?not?show?a?preference?for?C.?bovinus?territories.?Regardless?of?habitat?location?or?prior?captivity,?territorial?C.?bovinus?significantly?excluded?G.?nobilis?within?their?direct?vicinity?(5?cm),?but?not?from?their?entire?territory.?Decreased?G.?nobilis?density?within?the?habitat?may?allow?C.?bovinus?to?defend?their?breeding?territories?more?readily?during?the?summer?spawning?season.?This?study?provides?empirical?evidence?of?captively?raised?individuals?behaving?similarly?to?wild?indi-?viduals?upon?reintroduction?to?their?natural?habitat?and?support?for?conservation?methods?that?focus?on?common?limiting?factors?between?endangered?species?[Current?Zoology?60?(4):?527-533,?2014].

Contrary?to?the?nestling?phase,?the?post-fledging?phase?has?been?less?studied?probably?because?it?is?challenging?to?follow?the?chicks?after?they?fledge.?However,?this?phase?is?crucial?to?consider?when?focusing?on?the?life?cycle?of?individuals?because?it?is?associated?with?new?demands:?After?leaving?the?nest,?individuals?have?to?find?their?own?food?and?cope?with?a?new?set?of?previously?unknown?stressors.?In?this?study,?we?aimed?at?better?understanding?how?energetically?demanding?the?post-ftedging?period?is?in?house?sparrows?Passer?domesticus?by?measuring?several?indices?of?a?fledgling's?state?(body?condition,?fat?and?muscle?scores?and?plumage?quality).?If?the?energetic?demands?of?the?post-fledging?period?are?greater?than?those?of?the?adult?life,?we?predicted?that?fledglings?should?be?in?lower?condition?and?should?have?a?plumage?of?lower?quality?relative?to?adults.?Supporting?this?prediction,?the?condition?and?the?plumage?of?fledglings?differed?dramatically?from?those?of?adults.?Interestingly,?this?difference?disappeared?in?autumn.?Overall,?our?results?suggest?that?the?post-fledging?period?is?probably?one?of?the?most?energetically?demanding?of?the?life?cycle?in?this?species.?Supporting?this?idea,?the?resighting?probability?of?fledglings?was?lower?relative?to?adults.?However,?resighting?probability?depends?on?many?factors?(mortality,?dispersal,?habitat?use?and?behaviours)?and?future?studies?are?necessary?to?tease?apart?their?relative?importance?in?determining?resighting?probability?[Current?Zoology?60?(4):?449-459,?2014].

将共生理论引入到寒地建筑设计的研究领域,探索寒地建筑与环境共生系统的建构理论与方法;并通过设计实践,探讨基于自然环境、人工环境与人文环境的共生设计策略,为创造一体化互惠共生的寒地建筑与环境共生系统提供方法指引.

随着旅游市场竞争日趋激烈,目的地定位的重要性愈加突出.然而,国内研究和实践对"把握旅游者兴趣和需求"这一定位首要工作普遍认识不足,且实施不到位.鉴于此,本研究对目的地定位中"击中消费者心灵"这一关键环节的实施从理论和实证上进行了阐释.理论上,分析了目的地突出属性与定位之间的关系及当前国内误区.实证上,引入轮换方格分析法,以国内十大海滨城市目的地为要素,阐释了识别旅游者对竞争目的地相比较的目的地突出属性的方法程序.此外,对旅游者访谈结果与目的地业界代表访谈结果的比较发现,供需双方在旅游者需求的认识上不吻合.文章最后还对本研究的应用价值和局限做了总结.

为了研究地星上行和星地下行激光链路孔径内接收光强信号的典型特征,基于大气湍流理论和位相屏方法,计算了短波和中波红外激光在特定大气相干长度条件下,孔径内接收激光功率与总功率的比值及起伏情况。根据统计结果讨论了上下行大气通道传播特性的差异,结果表明相同外界条件下,直径50 cm孔径内接收的下行激光信号强度大于上行激光信号强度1个数量级以上,其信号的起伏程度也低于上行激光;中等湍流下,下行激光孔径接收光强的概率分布函数服从对数正态分布,最大概率接收功率比与无湍流条件下的功率比值一致,分别为0.42%(1.315μm )和0.26%(3.8μm )。

喜欢大自然的人总是希望能够沐浴在自然光线里,而传统的人工灯光总是差强人意."Sunn Light"绝对是热爱自然者的福音. Sunn Light可以模拟太阳光,打开它就好像拥有一个自己的太阳,它可以模仿早晨初升的朝阳温柔地唤醒熟睡的用户,可以模拟晚上野外温暖的篝火让用户身心放松的入睡,也可以模仿太阳被乌云遮住后透出阳光.

《体验大自然》丛书(全14册),[德]安科·库铂、[德]阿诺·科尔布、[德]芭尔贝尔·奥弗特林等著,荆妮、郑高风译,王宏审译,科学普及出版社.2011年出版,定价:19.80(每册).

我爱花园,源自父亲的熏陶及影响.父亲爱花,爱植物,爱生机勃勃的大自然.父亲应该有个花园,但始终没有.