Dependence of Melting Process on Size and Edge Type of Graphene Nanoribbon

The study of variation of the size, armchair and zigzag types effects on the melting process of graphene nanoribbon. A numerical  thermodynamical model has been devoted for the study. The phase transition has first order behaviour. The formation of different defects, ring size and coordination number is dependent on the size and the edge type of GNR. The nuclei of heating appear at temperature around 2300K and that can be considered as pre-melting point. The melting process shows the case that the results of Berezinsky-Kosterlitz-Thouless-Nelson-Halperin-Young (BKTNHY) theory cannot be applied.

Size and Layer Dependence of Hybrid Graphene/h-BN Models Upon Heating

Different models contained graphene layer are studied via molecular dynamics simulation. Models are heated up from 50K to 8000K via Tersoff and Lennard-Jones potentials to have an entire picture about the evolution of graphene layer in the models upon heating. Various thermodynamic quantities, structural characteristics, and the occurrence of liquidlike atoms are studied, such as, the total energy per atom, the heat capacity per atom, the radial distribution functions, and the appearance of liquid atoms upon heating. The phase transition exhibits the first order. The melting point of graphene layer depends on the number of layers in the models while it does not depend on the size in the range of this study. The melting process of hybrid graphene and hexagonal boron nitride (h-BN) satisfies the first step towards Devil's staircase type phase transition. The melting point of hybrid graphene/h-BN is close to the one of experiment of graphite

LGB Cancer Survivors are More Likely to Participate in Risky Behaviors than Straight Cancer Survivors, United States, Behavioral Risk Factor Surveillance System, 2014

Cancer registries do not collect sexual orientation in their records, leading to limited information about LGB cancer survivorship. Studies have shown that both the LGB population and the population of cancer survivors participate in risky behaviors (i.e. smoking, drinking, and being overweight/obese; sleep inadequacy among cancer survivors), but information about LGB cancer survivors is limited. 2014 Behavioral Risk Factor Surveillance System (BRFSS) data was used to determine if LGB cancer survivors were more likely to participate in risky behaviors than straight cancer survivors. LGB survivors were more likely to drink at least one alcoholic beverage within the past 30 days (AOR: 1.99, 95% CI: 1.44-2.75), to report being an ever smoker (AOR: 1.59, 95% CI: 1.12-2.25), and to binge drink (AOR: 1.99, 95% CI: 1.21-3.28) than straight cancer survivors. There is a strong association between sexual orientation among cancer survivors and risky behaviors. The findings of this study concludes that risky behaviors may be detrimental to the health and survivorship of LGB cancer survivors and further research is needed to determine the association between LGB cancer survivorship, being an adolescent and young adult (AYA), and risky behavior

U.S. - Vietnam Comprehensive Partnership Present an Possible

Relations between the United States and Vietnam entered a new era in July 2013 with the conclusion of the U.S.-Vietnam comprehensive partnership agreement announced by President Barack Obama and President Truong Tan Sang. The U.S.-Vietnam comprehensive partnership is an overarching framework for strengthening and deepening cooperation across nine sectors: political and diplomatic relations, trade and economic ties, science and technology, education and training, environment and health, war legacy issues, defence and security, protection and promotion of human rights, and culture, sports and tourism. It has been four years since the U.S.-Vietnam comprehensive partnership was officially launched. It is, therefore, time to assess this comprehensive partnership. The article will begin with a brief literature review which demonstrates the needs to produce a dedicated analysis of U.S.-Vietnam comprehensive partnership before examining the U.S. and Vietnamese concepts of a comprehensive partnership. It also seeks to explore what have motivated Hanoi and Washington to elevate their bilateral relations to a new height. The article goes on to evaluate developments in the U.S.-Vietnam relations from July 2013 up to July 2017 on five main sectors: economic ties, security cooperation, people-to-people ties, cooperation on humanitarian and war legacy issues, cooperation on regional and global challenges. It will demonstrate that the U.S.-Vietnam relationship has achieved important progresses since the announcement of the U.S.-Vietnam comprehensive partnership. Last but not least, the article will look at the possible shapes of the United States and Vietnam in the future

Robert G. Sutter.The United States and Asia: Regional Dynamics and Twenty First Century Relations.

Robert G. Sutter’s The United States and Asia: Regional Dynamics and Twenty-First-Century Relations is essential reading for anyone interested in U.S. relations to Asia. With a realist perspective, Sutter aims to assess the uncertainty and practice of US-Asian relations since the Cold War. He also seeks to analyze the regional multilateral groups, the security, economic, and political issues that determine the dynamics of U.S.-Asian relations. His overall adjustments on U.S. role in promoting..

Evolution of Boron Nitride Structure upon Heating

The evolution of structure upon heating of hexagonal boron nitride nanoribbon (h-BNNR) model is studied via molecular dynamics simulation. The temperature is increased from 50K to 5500K in order to observe the change of the structure during heating process. Various thermodynamic quantities related to the change of structure are calculated such as radial distribution functions, Lindemann criterion, the occurrence/growth of liquidlike atoms, the formation of clusters, and ring statistics. The melting point is defined. The phase transition from solid to liquid states exhibits first order behavior

Vietnamese upper-high school teachers’ views, practices, difficulties, and expectations on teaching EFL writing

Teaching EFL writing at the secondary level of education is one of the challenging tasks for every teacher. However, few studies on how EFL writing is taught at up-secondary schools (U-SS) have been reported. This study attempts to explore how Vietnamese teachers at this educational level perceived the importance of EFL writing, how they taught this skill, and what difficulties and expectations/suggestions they had in making the teaching of this skill at their own schools more effectively. Employing the 5-point Likert-scale survey with 20 teachers from five U-SS, classroom observations, and semi-structured interviews, the study found these teachers' understanding of the importance of teaching this skill, their confidence, and appropriate pedagogical use and content knowledge (PCK) in teaching it. However, their lack of time, the heavy contents in the textbooks, the multiple-choice test formats, large classes, students' dislike of this skill, and their insufficient knowledge of grammar and vocabulary challenged their teaching of this skill. With the suggestions/recommendations made by these teachers, this study is expected to provide some insights for relevant and timely support to teachers for the effectiveness of teaching this skill in the educational settings in Vietnam and in similar EFL contexts

Oliver Turner, American Images of China: Identity, Power, Policy

Oliver Turner’s book entitled American Images of China, which originated as a PhD thesis, aims to illustrate what American images of China have been and how they have shaped particular realities within which US policy on China has been formulated while potential alternatives have been ignored. Drawing on a wide range of primary source materials, the author is able to demonstrate the power of representations of China in American society in continuously building and rebuilding a China of Americ..

Does the non-farm sector affect production efficiency of the Vietnamese agricultural sector? A stochastic frontier production approach

This study examines the impact of the non-farm sector on farm value-added and production efficiency in the Vietnamese agricultural sector by using data from the Vietnam Household Living Standard Survey 2012. Production function and stochastic frontier production analysis is used to determine the impact, and the instrumental variables method is applied to address endogeneity. We find that the Vietnamese non-farm sector has a positive effect on both farm value-added and efficiency. This result indicates that income from non-farm activities relaxes liquidity constraints and farmers can reinvest this capital in agricultural production. Our result provides evidence of the important role played by the non-farm sector in relaxing credit constraints and enhancing agricultural production efficiency for developing countries