2,216 research outputs found
Odonata of Ayer Hitam Forest Reserve, Johor, Peninsular Malaysia
Odonata records from Ayer Hitam Forest Reserve and the surrounding area in Johor, Peninsular Malaysia are presented. A total of 44 Odonata species from eight families were collected in the area in October 2012. All of these records are new to Ayer Hitam Forest Reserve. Indothemis carnitica is a new record for Malaysia
Effect of Diethylenetriamine and Triethylamine sensitization on the critical diameter of Nitromethane
In this work, the critical diameter for detonation was measured for Nitromethane (NM) sensitized with two different amines: Diethylenetriamine (DETA) and Triethylamine (TEA). The critical diameter in glass and polyvinylchloride tubes is found to decrease rapidly as the amount of sensitizer is increased, then increase past a critical amount of sensitizer. Thus the critical diameter reaches a minimum at a critical concentration of sensitizer. It was also found that the critical diameter is lower with DETA than with TEA
Identifying The Salient Dimensions Of Student Cheating And Their Key Determinants In A Private University
Extensive research has been conducted over the years about the academic dishonesty or cheating among university students. Most of these studies usually involve surveys of students to determine the extent of their participation in unethical practices, reasons for their participation in these practices and how each unethical academic behavior is related to some student characteristics. While that approach offers good insights it fails to uncover the underlying salient dimensions or commonalties among these behaviors and motivations. This paper reports the results of a survey of business students concerning their academic honesty. Student self-reports on participation and reasons for participating in unethical practices are factor analyzed to uncover three salient dimensions of cheating and four compelling motivations for student cheating. Key determinants of the various forms of cheating are identified and policy implications are discussed
Herbal Remedies for Combating Irradiation: a Green Antiirradiation Approach
Plants play important roles in human life not only as suppliers of oxygen but also as a fundamental resource to sustain the human race on this earthly plane. Plants also play a major role in our nutrition by converting energy from the sun during photosynthesis. In addition, plants have been used extensively in traditional medicine since time immemorial. Information in the biomedical literature has indicated that many natural herbs have been investigated for their efficacy against lethal irradiation. Pharmacological studies by various groups of investigators have shown that natural herbs possess significant radioprotective activity. In view of the immense medicinal importance of natural product based radioprotective agents, this review aims at compiling all currently available information on radioprotective agents from medicinal plants and herbs, especially the evaluation methods and mechanisms of action. In this review we particularly emphasize on ethnomedicinal uses, botany, phytochemistry, mechanisms of action and toxicology. We also describe modern techniques for evaluating herbal samples as radioprotective agents. The usage of herbal remedies for combating lethal irradiation is a green antiirradiation approach for the betterment of human beings without high cost, side effects and toxicity
Effect of Extractives on Moisture Sorption and Shrinkage in Tropical Woods
Samples of sixteen tropical wood species from Indonesia were selected to undergo desorption and adsorption in the unextracted and extracted form. The anisotropic shrinkage values of these samples were also determined. At high humidities, the extracted woods exhibit higher equilibrium moisture contents than the unextracted woods. However, the isotherms of extracted and unextracted woods coincide at relative humidities below 70% for both desorption and adsorption. This phenomenon indicates that the hygroscopicity of wood is affected at high humidities through the extractives bulking the amorphous region in the cell wall. The shrinkage intersection point ranges from 18.0 to 34.1%, with an average of 24.8%, which is below the predicted 30% for temperate-zone woods. The linear relationship between volumetric shrinkage and specific gravity was significant, but the correlation (r2 = 0.40) is quite low. The removal of extractives with hot water and organic solvents caused excessive shrinkage. All the woods tested showed partial collapse, indicating the plasticization of the extractives at high temperature and high moisture content in the cell wall structure
Bioinformatics for Membrane Lipid Simulations: Models, Computational Methods, and Web Server Tools
Biological membranes are complex environments consisting of different types of lipids and membrane proteins. The structure of a lipid bilayer is typically difficult to study because the membrane liquid crystalline state is made up of multiple disordered lipid molecules. This complicates the description of the lipid membrane properties by the conformation of any single lipid molecule. Molecular dynamics (MD) simulations have been used extensively to investigate properties of membrane lipids, lipid vesicles, and membrane protein systems. All-atom membrane models can elucidate detailed contacts between membrane proteins and its surrounding lipids, while united-atom and coarse-grained description have allowed larger models and longer timescales up to microsecond mark to be probed. Additionally, membrane models with mixed phospholipids and lipopolysaccharide content have made it possible to model improved views of biological membranes. Here, we present an overview of commonly used lipid force fields by the biosimulation community, useful tools for membrane MD simulations, and recent advances in membrane simulations
Ruin Theory for Dynamic Spectrum Allocation in LTE-U Networks
LTE in the unlicensed band (LTE-U) is a promising solution to overcome the
scarcity of the wireless spectrum. However, to reap the benefits of LTE-U, it
is essential to maintain its effective coexistence with WiFi systems. Such a
coexistence, hence, constitutes a major challenge for LTE-U deployment. In this
paper, the problem of unlicensed spectrum sharing among WiFi and LTE-U system
is studied. In particular, a fair time sharing model based on \emph{ruin
theory} is proposed to share redundant spectral resources from the unlicensed
band with LTE-U without jeopardizing the performance of the WiFi system.
Fairness among both WiFi and LTE-U is maintained by applying the concept of the
probability of ruin. In particular, the probability of ruin is used to perform
efficient duty-cycle allocation in LTE-U, so as to provide fairness to the WiFi
system and maintain certain WiFi performance. Simulation results show that the
proposed ruin-based algorithm provides better fairness to the WiFi system as
compared to equal duty-cycle sharing among WiFi and LTE-U.Comment: Accepted in IEEE Communications Letters (09-Dec 2018
Social Media Marketing Strategy: Theory and Research Propositions
Despite the growing importance of social media in marketing, theoretical advances in our understanding of how to best deploy this media remains undeveloped. This paper argues that social media strategy should be based on understanding of social network structures and influence. Several research propositions are presente
The Full Range of Predictions for B Physics From Iso-singlet Down Quark Mixing
We extend the range of predictions of the isosinglet (or vector) down quark
model to the fully allowed physical ranges, and also update this with the
effect of new physics constraints. We constrain the present allowed ranges of
sin(2*beta) and sin(2*alpha), gamma, x_s, and A_{B_s}. In models allowing
mixing to a new isosinglet down quark (as in E_6) flavor changing neutral
currents are induced that allow a Z^0 mediated contribution to B-Bbar mixing
and which bring in new phases. In (rho, eta), (x_s, sin(gamma)), and (x_s,
A_{B_s}) plots for the extra isosinglet down quark model which are herein
extended to the full physical range, we find new allowed regions that will
require experiments on sin(gamma) and/or x_s to verify or to rule out an extra
down quark contribution.Comment: 13 pages in RevTeX, 7 postscript figure
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