眼控轮椅有望造福瘫痪者

香港中文大学学者最近发明了一种可以利用眼部肌肉控制的轮椅，只要使用者转动眼球便能使轮椅移动，这为瘫痪者带来了巨大方便。     

植物体内的胼胝质

胼胝质(callose)是一种以β-1，3-键结合的葡聚糖。在植物的筛管代谢、配子体发育等生命活动中发挥着重要的调节作用，其合成、分解直接关系植物正常的生长代谢过程，因此，胼胝质的代谢是植物研究中的重要内容之一。     

Chemical composition of volatiles from the syconia of Ficus microcarpa and host recognition behavior of pollinating fig wasps

Aims Chemical communication plays a key role in host plant recognition of pollinators. There are two recognized types of chemical communication between syconia and their pollinating fig wasps: one is “generalization”, of which the wasps respond to the relative ratio of multiple compounds, and the other is “specialization”, of which the key signal is a single uncommon, possibly unique, compound. The aims of this study were to identify the chemical composition of volatiles from the syconia of Ficus microcarpa at different developmental phases, and to determine if the signaling between F. microcarpa and its pollinating fig wasp, Eupristina verticillata, is of generalized type, or of specialized type.Methods The volatiles from syconia of F. microcarpa were extracted using solid-phase micro extraction (SPME) at different developmental phases (pre-female, female (before and after pollination), interfloral, male and postfloral phases) and the chemical compounds were identified by gas chromatography mass spectrometry (GC-MS). We then tested the behavioral responses of E. verticillata to fresh syconia at different developmental phases using two-choice olfactometers.Important findings There were 21 volatile compounds identified from the syconia at different developmental phases, which were mainly fatty acid derivatives, terpenoids and aromatic compounds. The components of the volatiles apparently differed among the developmental stages. The contents of terpenoids declined, but the contents of fatty acid derivatives increased, from before the pollination to after the pollination. Especially, the characteristic compounds of 2-heptanone and 3-octanone before the pollination disappeared, D-limonene decreased after the pollination, but copanene, cyclohexane and 2-hexenal increased. The results of the two-choice olfactometer experiment showed that the pollinating fig wasps had higher selection ratio to chemicals found in the female phase syconia than those in other phases; whereas the volatile compounds from the male phase syconia had the function pushing the pollinating fig wasps to leave the natal syconia so that there existed the “push-pull” responses by fig wasps to volatiles released by their host syconia. We conclude that there are multiple chemical compounds playing the roles in host recognition of pollinating fig wasp E. verticillata. The mutualistic relationship between F. microcarpa and E. verticillata is maintained by the chemical communication of “generalization” strategy.     

“蓝牙”手机求救系统发送心脏求救短信

美国国际商用机器公司(IBM)的研究人员又给手机增添了一项新功能:为心脏病高危者发送求救信息。IBM公司的新型心脏病手机求救系统的核心是只有一盒口香糖大小的无线电信号转发装置,这一装置采用了可进行短距离、低功率无线通信的“蓝牙技术”,可与便携式心跳监测仪和手机配合使     

芯片植入体内可救命

美国科学家制出一种可以植入手臂的“救命”芯片。植入者一旦发生意外，医生就能根据芯片代码，搜索到植入者的相关信息，采取针对性治疗。     

金沙江干热河谷特有植物白魔芋的传粉生物学研究

以金沙江干热河谷特有植物白魔芋（Amorphophallus albus P.Y.Liu et J.F.Chen）为对象，分别在两个就地栽培实验地（四川金阳、云南永善）和一个异地栽培实验地（富源）进行传粉生物学研究（包括交配系统及气味和传粉昆虫对其繁殖策略的影响）。结果显示，白魔芋是雌雄异熟且雌蕊先熟，雌花期时，附属器散发浓烈的恶臭气味。经气相色谱-质谱联用仪（GC-MS）分析，花气味成分主要为二甲基二硫和二甲基三硫。野外观察到的传粉昆虫属于隐翅虫科（Staphylinidae），包括前角隐翅虫亚科（Aleocharinae）的Atheta sp.和颈隐翅虫亚科（Oxytelinae）的Anotylus sp.。经气相色谱-触角电位联用技术（GC-EAD）分析表明，隐翅虫触角对白魔芋花气味中的二甲基二硫和二甲基三硫有明显的反应。授粉结果显示，金阳、永善和富源3个实验地人工自花授粉和套袋的结实率都为0，无传粉昆虫的富源实验地自然结实率也为0。综合研究结果表明白魔芋属于自交不亲和的交配系统，通过花序结构和气味吸引隐翅虫为其传粉，并提供食物和交配场所作为回报。该研究为白魔芋的繁殖育种提供了基础资料，为植物与昆虫之间的协同进化提供了进一步的理论支持，同时为白魔芋的有效保护和利用提供了理论依据和技术指导。     

有花植物与传粉动物

绝大多数被子植物及少数裸子植物需要昆虫或动物传粉才能完成受精。除人们所广泛熟悉的蜂类、蝶蛾类是重要的传粉者以外,还有许多其它无脊椎动物和脊椎动物起着积极的传粉作用。传粉动物与植物之间的密切关系是生物之间互惠互益、协同适应的典范。一、无脊推动物传粉的植物 1.适于甲虫传粉的植物甲虫传粉是热带植物的特征,就象蜜蜂传粉是温带植物的特征。甲虫是昆虫中最古老的类型,