Lightweight Trusted Security for Emergency Communication Networks of Small Groups

Public communication infrastructures are susceptible to disasters. Thus, the Emergency Communication Networks(ECNs) of small groups are necessary to maintain real-time communication during disasters. Given that ECNs are self-built by users, the unavailability of infrastructures and the openness of wireless channels render them insecure. ECN security, however, is a rarely studied issue despite of its importance. Here, we propose a security scheme for the ECNs of small groups. Our scheme is based on the optimized Byzantine Generals’ Problem combined with the analysis of trusted security problems in ECNs. Applying the Byzantine Generals’ Problem to ECNs is a novel approach to realize two new functions, debugging and error correction, for ensuring system consistency and accuracy. Given the limitation of terminal devices, the lightweight fast ECDSA algorithm is introduced to guarantee the integrity and security of communication and the efficiency of the network. We implement a simulation to verify the feasibility of the algorithm after theoretical optimization.

Poverty Alleviation Program Helps “Small Ethic Minority Groups”

Here we were at a picturesque village inhabited by the ethnic Kinos, one of the smallest ethnic minority groups in China. Immediately beyond the village, Bapiao, a highway snakes deep into the rolling mountains until it reaches Jinghong, the capital city of Xishuangbanna Dai Autonomous Prefecture, Yunnan Province. When New China was founded in 1949, there were no more than 3,800 ethnic Kinos engaging in slash-and-bum farming for a meager subistence in those deep, subtropical lbrests. Now the Kino population has multiplied, and they have settled in 45 villages under the jurisdiction of a self-governing township.

Triadic Synchrony: Application of Multiple Wavelet Coherence to a Small Group Conversation

By applying multiple wavelet coherence (MWC) to data from human body movements in triadic interaction, this study quantified triadic synchrony, rhythmic similarity among three interactants. Thirty-nine Japanese undergraduates were randomly assigned in a triad, and engaged in a brain-storming task. Triadic synchrony was quantified by calculating MWC to the time-series movement data collected by Kinect v2 sensor. The existence of synchrony was statistically tested by using a pseudo-synchrony paradigm. Results showed that the averaged value of MWC was higher in the experimental participant trio than in those of the pseudo trio in the frequency band of 0.5 - 1 Hz. The result supports the possible utility of applying multiple wavelet coherence to evaluate triadic synchrony in a small group interaction.

Undergraduate Medical Students＇ Perception about Learning in Small Group at University of Sharjah

Learning in small groups is a key instructional strategy in medicine and more so in the problem based curriculum （PBL）. It is perceived that working in small groups enhances acquisition, processing and retention of the ever increasing medical knowledge. Learning in small group will help the students to be better learner and improve their personal, social and cognitive skills. The objective of this study is to describe undergraduate medical students＇ perception toward small group learning in a PBL curriculum. A cross-sectional descriptive study was conducted among the undergraduate medical students in the phase 2 of their MBBS program at University of Sharjah. A total of 277 undergraduate medical students participated in the study. The mean age of the study population was 20 years and 61% were female students. The most rewarding experiences as perceived by medical students were exposure to different views （71%）, making friends （57%） improving their grades （52%） and underwent personal development （46%）. The main disadvantages of small group learning were waste of time （55%）, side talks （16%）, and other distractions （14%）. Majority of students had a positive perception towards small group learning and agreed that it enhances their collaborative learning and team work skills. Small group learning was perceived as a key instructional method in the PBL curriculum [3] and it enhances their grades, learning outcomes, personal development and critical thinking abilities [4].

A Survey on Students＇ Group Discussion in Conversation Class

This article makes an investigation of 114 English majors＇ level of a particular communicative performance and the general ability to perform in small-group conversations in their conversation class, and thereafter explores the reasons for their current level with the aid of questionnaire based on a rating scale, together with observation and interviews. Some countermeasures are provided to call for teachers＇ attention in their teaching practice.

Cultural Route of Ancient Villages and Towns in Zhuozhang River Valley

Shanxi Zhuozhang River Basin has a long history of human habitation,which is one of important cradles of Central-Plains civilization.It has a distinctive valley landscape and holds the glorious Shangdang culture through the Fukou pathway of the ancient 8 valley pathways in Taihang,one of the main activities of Shanxi Lu Trader,and the old revolutionary base areas of Chinese Communist Party.Within the study area,the common factors infl uencing the ancient villages and towns space characteristics were systematically revealed from fi ve aspects of valley landscape environment,Lu Trader development lines,Buddhism propagation path,regional folklore and military activity site.By exploring the uniqueness and similarity,this study analyzed the spatial pattern of ancient villages and towns in the Zhuozhang River Basin and the infl uence of natural,social and historical factors.The feasibility of constructing cultural route in the Zhuozhang River Basin was demonstrated.

TEACHING WRITING THOUGH SMALL GROUP CONFERENCING

In view of the fact that most college English teachers in China invest a great deal of time andeffort responding to students’ writing,but find students improve so little in their writing skills,I ventureto put forward an alternative way of teaching writing in the paper,that is,teaching writing throughsmall group conferencing.Compared with the traditional teaching methods,small group conferencing hasfollowing advantages:(1)Saving evaluation time;(2)Providing better feedback;(3)Helping studentscritique their writing,etc.Since many empirical studies and teaching practices demonstrate that smallgroup conferencing is an effective and efficient way of teaching writing,we have good reason to believethat it will become widespread in the college English teaching in China.

Imprinting in Plants and Its Underlying Mechanisms

Genomic imprinting（or imprinting） refers to an epigenetic phenomenon by which the allelic expression of a gene depends on the parent of origin.It has evolved independently in placental mammals and flowering plants.In plants,imprinting is mainly found in endosperm. Recent genome-wide surveys in Arabidopsis,rice,and maize identified hundreds of imprinted genes in endosperm.Since these genes are of diverse functions,endosperm development is regulated at different regulatory levels.The imprinted expression of only a few genes is conserved between Arabidopsis and monocots,suggesting that imprinting evolved quickly during speciation.In Arabidopsis,DEMETER （DME） mediates hypomethylation in the maternal genome at numerous loci（mainly transposons and repeats） in the central cell and results in many differentially methylated regions between parental genomes in the endosperm,and subsequent imprinted expression of some genes.In addition,histone modification mediated by Polycomb group（PcG） proteins is also involved in regulating imprinting.DME-induced hypomethylated alleles in the central cell are considered to produce small interfering RNAs（siRNAs） which are imported to the egg to reinforce DNA methylation.In parallel,the activity of DME in the vegetative cell of the male gametophyte demethylates many regions which overlap with the demethylated regions in the central cell.siRNAs from the demethylated regions are hypothesized to be also transferred into sperm to reinforce DNA methylation.Imprinting is partly the result of genome-wide epigenetic reprogramming in the central cell and vegetative cell and evolved under different selective pressures.