The Distribution of Repetitive DNAs Along Chromosomes in Plants Revealed by Self-genomic in situ Hybridization

The distribution of repetitive DNAs along chromosomes is one of the crucial elements for understanding the organization and the evolution of plant genomes. Using a modified genomic in situ hybridization （GISH） procedure, fluorescence in situ hybridization （FISH） with genomic DNA to their own chromosomes （called self-genomic in situ hybridization, self-GISH） was carried out in six selected plant species with different genome size and amount of repetitive DNA. Nonuniform distribution of the fluorescent labeled probe DNA was observed on the chromosomes of all the species that were tested. The signal patterns varied among species and were related to the genome size. The chromosomes of the small Arabidopsis genome were labeled almost only in the pericentromeric regions and the nucleolus organizer regions （NORs）. The signals in the relatively small genomes, rice, sorghum, and Brassica oleracea var. capitata L., were dispersed along the chromosome lengths, with a predominant distribution in the pericentromeric or proximal regions and some heterochromatic arms. All chromosomes of the large genomes, maize and barley, were densely labeled with strongly labeled regions and weakly labeled or unlabeled regions being arranged alternatively throughout the lengths. In addition, enhanced signal bands were shown in all pericentromeres and the NORs in B. oleracea var. capitata, and in all pericentromeric regions and certain intercalary sites in barley. The enhanced signal band pattern in barley was found consistent with the N-banding pattern of this species. The GISH with self-genomic DNA was compared with FISH with Cot-1 DNA in rice, and their signal patterns are found to be basically consistent. Our results showed that the self-GISH signals actually reflected the hybridization of genomic repetitive DNAs to the chromosomes, thus the self-GISH technique would be useful for revealing the distribution of the regions where repetitive DNAs concentrate along chromosomes and some chromatin differentiation associated with repetitive DNAs in plants.

艺术感知简论

写作中有句老话,观察是创作的第一步。在心理学上,观察就是心理感知。如果说文艺创作过程可以分为唤起情感.孕育情感和表达外化情感三个阶段的话,那么感知至少在两个阶段发生作用.在第一个阶段,感知作为主体感受和认识世界的唯一通道,是唤起情感的必然前提.决没有无感知的感受,和无感受的创作.在第三阶段,情感的形象外化过程中,总要通过感知来评估语言符号是否准确地传达出第二阶段艺术构思的设想.

暗恋疤痕

我是在16岁那年,冒出第一颗痘痘的时候,突然哀伤地意识到,自己对男生榭的爱恋,已是藤蔓一样,在心底疯狂地铺展开来,它将一整颗敏感脆弱的心,牢牢地包裹住,直至最后,连呼吸的余地,都不给我留下。我只能在上课的时候,看着榭清瘦的脊背,红着脸发一会儿呆。他的头发浓密茂盛,每次上完体育课回来,看到上面津津的汗水。

Cryptanalysis on an organization-friendly blockchain system

To verify that an organization-friendly blockchain system may suffer from forgery and collusion attacks,forgery and collusion attacks were theoretically carried out according to the phase sequence of an organization-friendly blockchain system.Then,the organization-friendly blockchain system was improved and based on the phase sequence forgery and collusion attacks were conducted.The results show that the attacker can obtain illegal transaction data from forgery and collusion attacks on the organization-friendly blockchain system.However,for the improved organization-friendly blockchain,the attacker s forgery and collusion attacks cannot be completed.Therefore,the organization-friendly blockchain system may be subject to forgery and collusion attacks,but the improved organization-friendly blockchain system can prevent such attacks.

Protocol for Trusted Channel Based on Portable Trusted Module

Web-based e-commerce applications need a trusted channel,which provides confidential communication,identity authentication and integrity assurance of endpoints,to guarantee the security of electronic transactions.A user-oriented trusted computing system based on Portable Trusted Module(PTM)is presented.Remote attestation is incorporated into Transport Layer Security(TLS)handshake protocol based on PTM so as to establish a trusted channel between two endpoints in network.This protocol can resist masquerading,trusted path and runtime attacks and propagate the trust in the computing system to the end user effectively.The test results of our proof-of-concept prototype show that our protocol for trusted channel is feasible for deployment in e-commerce applications on the Internet.

Fitness of Hybrids between Gossypium barbadense and Upland Cotton and Resistance to Pectinophora gossypiella and Alabama argillacea

Measuring fitness is essential for understanding the potential impacts of hybridisation between transgenic crops and their wild relatives. Transgenic CrylAc cotton Gossypium hirsutum and G. barbadense hybridise, the latter being valued as backyard cotton and an important genetic resource. G. barbadense was outcrossed to G. hirsutum containing the gene CrylAc and the isoline and the offspring evaluated for fitness as a measure of resistance to common pests and other growth parameters, Resistance to Pectinophora gossypiella and Alabama argillacea were greater in transgenic plants. Number of seeds per plant was higher in the F1 hybrids and G. hirsutum, F2 populations were intermediary; G. barbadense produced the least seeds per plant during the period of analysis. Anthesis of the first flower and opening of the first boll occurred earlier for G. hirsutum and Ft hybrids than F2; latest for G. barbadense. The observed-performance of resistance to the worms in the hybrids suggests that among FI and F2 populations transgenic hybrids may exhibit a competitive advantage over non-transgenic plants as a result of gene flow.

走过欲望的沼泽地……

一、资助了十年的女孩要以身相许在报社工作的妻子出差在外,十岁的儿子也回他姥姥家了。在区直某单位任职的我晚饭后来到办公室欲加班整理点材料。刚坐下,突然接到李冰的电话,说她有急事,让我马上到校门口接她。我问她什么事她怎么都不肯在电话里说。

新州笔记之四

烂塌麻糍烂塌麻糍从小屋里精穷卵出,却也算上过私塾。何有斯说?盖因当时他娘正好在上仓门石三店王府上当烧镬婆,他就整日跟屁虫一般的跟去,一不留神便跑到书房屋里,踮起双足,努力趴在窗盘沿上,一门归心地听乔儒先生给小店王授课。乔儒先生是前清秀才,谦谦然有君子风,对此从不干涉,睁只眼闭只眼的任他旁听。有心栽花花不发,无心插柳柳成荫,一来二去,小店王无论怎般努力都无法记住的三百千,竟被烂塌麻糍背得滚瓜烂熟。

审判者还是仲裁者

在一个刮着冷风雨的早上,我们到了法兰克福的法院街,好几栋大建筑,全是司法机构。听说闲来无事的老太太们喜欢来这里听审,法庭上的恩恩怨怨比电视剧还好看。大楼外有告示地图,告诉"听众"或者说"观众",该到哪里去。没看到一个警察。大门一推就进去了。

α-secretase ADAM IO physically interacts with β-secretase BACE1 in neurons and regulates CHL1 proteolysis

α-secretase and β-secretase are known to compete for amyloid precursor protein （APP） processing and thus play a vital role in Alzheimer＇s disease pathogenesis. A disintegrin and metaUoproteinase 10 （ADAM10） and β-site APP cleaving enzyme 1 （BACE1） mediate the major activities of α-secretase and β-secretase in brain and share various common substrates. However, whether they function separately or together is poorly understood. Here, we show that ADAM10 and BACE1 co-localize in the neurites of mouse primary neurons. Co-immunoprecipitation and fluorescence resonance energy transfer analysis revealed that ADAM10 and BACE1 interact with each other under both endogenous and exogenous conditions. In addition, we found that ADAMIO enhances the proteolysis of neural cell adhesion molecule close homolog of L1 （CHL1） by BACE1. Further studies found that ADAM10-BACE1 interaction interfering peptide LT52 attenuates the regulation of ADAM10 on BACEl-mediated cleavage of CHL1. Our data indicate that ADAM10-BACE1 interaction regulates the proteolysis of some specific substrates and may play a potential role in brain function.

EXPLORING THE COMMUNICATIVE POTENTIAL OF PHYSICAL RESPONSE TO VERBAL STIMULI

This paper discusses various teaching scenarios in which physical response may be employed to balance verbal response. Physical actions and movements make meaningful alternative activities that can achieve concentration and alertness from learners. They serve to reduce stress, create an informal and spontaneous atmosphere of learning, and facilitate language acquisition. The potential of physical response is especially noteworthy in eliciting interaction and stimulating communication based on reading texts. Many activities of this kind can be used to review and memorize vocabulary and to act out the parts on which the teacher would like the students to focus. Physical activities become even more practical and applicable when realia are combined to assist the performer who may find a particular action or movement hard to perform.

Traumatic bilateral hip dislocation with bilateral sciatic nerve palsy

Bilateral hip dislocation rarely occurs. In this paper, a case of bilateral hip dislocation associated with bilateral sciatic nerve palsy resulted from a road traffic accident is reported. Both hips were emergently reduced under general anaesthesia. Acetabular reconstruction was done bilaterally due to the unstable hips. The patient subsequently developed heterotopic ossification and avascular necrosis on the left hip and underwent total hip arthroplasty. The sciatic nerve on the right side achieved complete recovery but that on the left side only partly recovered and was augmented by tendon transfer. Such injuries are serious and one should be aware of the complications because they can resurface and so patients should be followed up for a long time. To the best of our knowledge, this kind of injury has not been reported in the English .language literature.

Sexual selection in cane toads Rhinella marina： A male＇s body size affects his success and his tactics

Abstract Male body size can play an important role in the mating systems of anuran amphibians. We conducted labora- tory-based trials with cane toads Rhinella （Bufo） marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male＇s body size on his reproductive success and behavior （mate choice）. Males were stimulated with a synthetic hormone to induce reproductive readiness. Larger body size enhanced a male toad＇s ability to displace a smaller rival from amplexus, apparently because of physical strength： more force was required to dislodge a larger than a smaller amplectant male. A male＇s body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size prefe- rence was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs： males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex iden- tification （one of the individuals involved is almost certainly a female）. Thus, a male cane toad＇s body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs

Age of maturation and behavioral tactics in male yellow ground squirrel Spermophilus fulvus during mating season

Life-history theory predicts that in hibemators age of maturation is related positively to body size and negatively to the duration of active season aboveground. Yellow souslik is a large-sized ground squirrel with long hibernation, which suggests late maturation. We used four-year field observations of marked individuals to determine the age of maturation in males through analysis of age-dependent variation in body size, mass, androgen status, timing of spring emergence, ranging patterns and social behavior during the mating season. Yearling males were smaller, lighter, had lower level of fecal testosterone, emerged later and had smaller home ranges than older males. Social activity and the number of females encountered did not differ between age classes. After the second hibernation none of the studied parameters varied with age. Cluster analysis revealed two behavioral tactics： ＂active＂ males （adults only） emerged earlier, ranged more widely, initiated more contacts, encountered more females and were heavier than ＂passive＂ males （both yearling and adult）. Thus, males of S. fulvus reached adult size and matured after two hibernations, which is relatively fast for such a big species with short active period. Indirect evidence for copulations and high variation among yearlings in all parameters suggest that some of them might successfully compete with adults. Active tactic of wandering and searching for females is energetically costly, and probably only adult males in good physical condition can afford it, whereas passive tactic of residing is energy saving and good for adults in poor condition and for yearlings that are continuing to grow.

A novel algorithm to counter cross-eye jamming based on a multi-target model

Cross-eye jamming is an electronic attack technique that induces an angular error in the monopulse radar by artificially creating a false target and deceiving the radar into detecting and tracking it.Presently,there is no effective anti-jamming method to counteract cross-eye jamming.In our study,through detailed analysis of the jamming mechanism,a multi-target model for a cross-eye jamming scenario is established within a random finite set framework.A novel anti-jamming method based on multitarget tracking using probability hypothesis density filters is subsequently developed by combining the characteristic differences between target and jamming with the releasing process of jamming.The characteristic differences between target and jamming and the releasing process of jamming are used to optimize particle partitioning.Particle identity labels that represent the properties of target and jamming are introduced into the detection and tracking processes.The release of cross-eye jamming is detected by estimating the number of targets in the beam,and the distinction between true targets and false jamming is realized through correlation and transmission between labels and estimated states.Thus,accurate tracking of the true targets is achieved under severe jamming conditions.Simulation results showed that the proposed method achieves a minimum delay in detection of cross-eye jamming and an accurate estimation of the target state.