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91.
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93.
Successful or unsuccessful female transfers were observed seven times during a 32-month field study of proboscis monkeys (Nasalis larvatus) inhabiting a riverine forest along a tributary of the Kinabatangan River, Sabah, Malaysia. In all cases, the females voluntarily left their own groups and immediately joined with another one. When adult females tried to shift to other groups, adult males called them back to their own groups, but appeared to be indifferent to subadult females. When the adult females returned, the males never attacked the females physically, but instead often emitted herding sounds to them. One subadult female was repelled by a resident adult female. When one adult female transferred into a new one-male group, she left her behind son in an all-male group. The number of females often fluctuated in most study groups, with this fluctuation being more prominent among subadult females than adult females. It is likely that female transfer in proboscis monkeys is not a rare occurrence and that it is especially common among sub-adult females.  相似文献   
94.
Anthemis cotula is a widespread invasive alien species in Kashmir Himalaya. Being a winter annual, the species reproduces entirely by achenes and synchrony between germination requirements of the species and the habitat conditions must be of critical importance in its invasiveness. To examine how the achenes of different ages respond to different environmental cues, two laboratory experiments were performed wherein effects of different nitrogen applications and growth hormones under continuous light and dark conditions were explored. Results show that the achenes are positively photoblastic and have requirement for after‐ripening. Nitrogen applied either as potassium nitrate or as thiourea significantly improved achene germination both under continuous light and dark conditions. Although kinetin (6‐furfurylaminopurine) did not influence achene germination, gibberellic acid (GA3) applied at 1.0 mM concentration had the most significant effect on the final percentage germination under both light and dark conditions. These results suggest that the achenes have an elaborate mechanism of sensing the habitat conditions that helps them to synchronise their germination with favourable environmental conditions – a strategy that aids the species in ensuring recruitment, survival and its spread in Kashmir Himalaya.  相似文献   
95.
Towards the goal of developing a real-time monitoring device for microorganisms, we demonstrate the use of microcantilevers as resonant mass sensors for detection of Bacillus anthracis Sterne spores in air and liquid. The detection scheme was based on measuring resonant frequency decrease driven by thermally induced oscillations, as a result of the added mass of the spores with the use of a laser Doppler vibrometer (LDV). Viscous effects were investigated by comparing measurements in air and deionized (DI) water along with theoretical values. Moreover, biological experiments were performed which involved suspending spores onto the cantilevers and performing mass detection in air and water. For detection of spores in water, the cantilevers were functionalized with antibodies in order to fix the spores onto the surface. We demonstrate that as few as 50 spores on the cantilever can be detected in water using the thermal noise as excitation source. Measurement sensitivity of 9.23 Hz/fg for air and 0.1 Hz/fg for water were obtained. These measurements were compared with theoretical values and sources of improvement in cantilever sensitivity in a viscous medium were also discussed. It is expected that by driving the cantilevers and using higher order modes, detection of a single spore in liquids should be achievable.  相似文献   
96.
The superior performance of F1 hybrids has a significant impact on agricultural productivity. For commercial application, the availability of an efficient system for obtaining male-sterile lines of crops is an essential prerequisite. Here we have investigated the use of RNA interference (RNAi) technology to silence a male-specific gene in the model host tobacco. TA29 is expressed exclusively in anthers at the time of microspore development. About 10 out of 13 tobacco lines transformed with a hairpin RNAi construct containing TA29 sequences were male sterile. Transgenic plants were phenotypically indistinguishable from non-transgenic plants. At the anthesis stage, pollen grains from transgenic, male-sterile plants were aborted and lysed in comparison to the round and fully developed pollen in non-transgenic plants. Microscopic analysis of anthers showed selective degradation of tapetum in transgenic plants with no microspore development. One week after self-pollination, the ovules of non-transgenic plants were double the size of those in transgenic plants, due to successful self-fertilization. Male sterile transgenic plants set seed normally, when cross-pollinated with pollen from non-transgenic plants, confirming no adverse effect on the female parts of the flower. These results show that silencing of male-specific genes by RNAi is potentially a useful tool for generating male-sterile lines for producing hybrid seed.  相似文献   
97.
The reef fisheries of Pulau (meaning “island” in Malay) Banggi, Sabah are not managed, and lack baseline fisheries data despite forming part of a proposed marine park. Thus, a combination of qualitative and quantitative approaches was applied to obtain a baseline picture about the past and present state of the fisheries. Fish landings were monitored, and fisher interviews conducted to investigate seasonal effects and historical changes in Banggi’s reef fisheries. Monsoon winds were a major driver of seasonal differences in catch quantities for the hook and line, but not the gillnet fishery. Spatial distribution of fishing effort and target species also differed by season. Fishers consistently indicated that Banggi’s fisheries were declining, with a suggested three to four times decrease in catch rates over the last 20 years. Interestingly, it appeared that substantial decreases began in the year 2000. The responses of fishers to seasonal changes, and the resultant implications for management are discussed. Importantly, the need for immediate management policies to prevent further declines and to maintain sustainable reef fisheries is stressed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
L. S. L. TehEmail:
  相似文献   
98.
Most, if not all, of the neocortex is multisensory, but the mechanisms by which different cortical areas - association versus sensory, for instance - integrate multisensory inputs are not known. The study by Lakatos et al. reveals that, in the primary auditory cortex, the phase of neural oscillations is reset by somatosensory inputs, and subsequent auditory inputs are enhanced or suppressed, depending on their timing relative to the oscillatory cycle.  相似文献   
99.

Background

Annotations that describe the function of sequences are enormously important to researchers during laboratory investigations and when making computational inferences. However, there has been little investigation into the data quality of sequence function annotations. Here we have developed a new method of estimating the error rate of curated sequence annotations, and applied this to the Gene Ontology (GO) sequence database (GOSeqLite). This method involved artificially adding errors to sequence annotations at known rates, and used regression to model the impact on the precision of annotations based on BLAST matched sequences.

Results

We estimated the error rate of curated GO sequence annotations in the GOSeqLite database (March 2006) at between 28% and 30%. Annotations made without use of sequence similarity based methods (non-ISS) had an estimated error rate of between 13% and 18%. Annotations made with the use of sequence similarity methodology (ISS) had an estimated error rate of 49%.

Conclusion

While the overall error rate is reasonably low, it would be prudent to treat all ISS annotations with caution. Electronic annotators that use ISS annotations as the basis of predictions are likely to have higher false prediction rates, and for this reason designers of these systems should consider avoiding ISS annotations where possible. Electronic annotators that use ISS annotations to make predictions should be viewed sceptically. We recommend that curators thoroughly review ISS annotations before accepting them as valid. Overall, users of curated sequence annotations from the GO database should feel assured that they are using a comparatively high quality source of information.  相似文献   
100.

Myzus persicae is a devastating pest affecting potato production. Intron-containing hairpin RNA (ihpRNA) silenced the odorant-binding protein 8 (OBP8) for enhanced protection against Myzus persicae in potatoes. OBP8 was isolated from M. persicae, sequenced, with the allotment of GenBank ID. ERNAi was used to design siRNA targets from OBP8 with no off-targets. Multiple Sequence Alignment show M. persicae OBP8 resemblance with Acyrthosiphon pisum, Rhopalosiphum maidis, Aphis fabae, and Sitobion avenae. dsRNA-OBP8 (7 µg/µL) oral feeding resulted in a 69% mortality, and 58% OBP8 reduced expression 8D post-feeding compared to control. Golden Gate cloning is used for RNA interference taking advantage of type IIs restriction enzyme Eco31I. ihpRNA-OBP8 introduced by agroinfiltration in Solanum tuberosum. Transgenic S. tuberosum fed Myzus show 57.6% mortality and 49% reduction in OBP8 expression 8D post-feeding, compared to control. This work proves OBP8 as promising ihpRNA targets in potato and related crops for whom Myzus is a destructive pest.

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