Living in the shadow of Mauna Loa

Thesis (S.M. in Science Writing)--Massachusetts Institute of Technology, Dept. of Comparative Media Studies, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (pages 30-44).One of Hawaii's most dangerous natural hazards is sitting in plain sight: Mauna Loa volcano. The mighty mountain makes up more than fifty percent of the island and is the largest volcano on Earth. Since 1843, when people started rigorously recording Mauna Loa's eruptive activity, the volcano has produced raging lava flows, billowing sulfuricrich clouds, and giant ground cracks, as well as triggered earthquakes, landslides, and even tsunamis. While geologists and emergency managers are concerned about and actively preparing for a future eruption, Hawaii's general public is largely ignorant or apathetic to their risk. This thesis explores what a future Mauna Loa eruption may look like in terms of geology, disaster response, and damage. It also identifies and profiles the most threatened Hawaiian communities and industries, as well as explores the factors driving differences in risk perception across various stakeholders on the island.by Zahra R. Hirji.Thesis (S.M. in Science Writing)--Massachusetts Institute of Technology, Dept. of Comparative Media Studies, 2013

Association between generation gap in interest, familiarity and application of information and communication technology

Given the introduction of information and communication technology and its rapid progress in every society, its use and application is different between various social institutions in that it demonstrates the difference between previous and present generation. Hence, the research was conducted in the school year 2012-2013 with the aim of applying information technology among female high school students and their mothers in Gorgan Province. The research method is a descriptive-analytical method; using a cluster sampling, of 34 female schools 8 schools were randomly chosen and 260 students were included in the study out of 1625 students. Using collected questionnaires and information obtained from independent t-test the results indicated that there was a significant difference between the mean of familiarity, interest and mothers' and their children's use of information technology. © Medwell Journals, 2016

Effects of Microstructure Formation on the Stability of Vapor Deposited Glasses

Glasses formed by physical vapor deposition (PVD) are an interesting new class of materials, exhibiting properties thought to be equivalent to those of glasses aged for thousands of years. Exerting control over the structure and properties of PVD glasses formed with different types of glass-forming molecules is now an emerging challenge. In this work, we study coarse grained models of organic glass formers containing fluorocarbon tails of increasing length, corresponding to an increased tendency to form microstructures. We use simulated PVD to examine how the presence of the microphase separated domains in the supercooled liquid influences the ability to form stable glasses. This model suggests that increasing molecule tail length results in decreased thermodynamic and kinetic stability of the molecules in PVD films. The reduced stability is further linked to the reduced ability of these molecules to equilibrate at the free surface during PVD. We find that as the tail length is increased, the relaxation time near the surface of the supercooled equilibrium liquid films of these molecules are slowed and become essentially bulk-like, due to the segregation of the fluorocarbon tails to the free surface. Surface diffusion is also markedly reduced due to clustering of the molecules at the surface. Based on these results, we propose a trapping mechanism where tails are unable to move between local phase separated domains on the relevant deposition time scales

The Use of Jigsaw Technique in Improving Students' Ability in Writing a Descriptive Text

This research was aimed at investigating whether there is any improvement of students' writing ability in writing a descriptive text by the implementation of Jigsaw technique and discover students' response to the use of Jigsaw technique in teaching writing descriptive text. This research employed quantitative method in the forms of quasi-experimental design. This quantitative research involved two classes of tenth grade at one senior high school in West Bandung in which one class was assigned as the experimental group and the other one was assigned as the control group. The instruments used were pre-test, post-test, and questionnaire of attitudes towards the Jigsaw technique. The post-test scores of the two groups were compared by using Independent t-test. The results showed the significance value was lower than the significance level which was 0.043 < 0.05. It meant that the Jigsaw technique improved students' ability in writing a descriptive text. Based on students' attitudes toward the use of Jigsaw technique, the findings indicated that most of students rated the used technique moderately positive. Nearly all of students agreed that Jigsaw technique is able to improve their writing skill, advance their grammatical mastery, increase their vocabulary mastery, expand their creative thinking, and improve their presentation skill as well as their confidence

The emergence of interface states in graphene/transition metal dichalcogenides heterostructure with lateral interface

The relative strength of different proximity spin-orbit couplings in graphene on transition metal dichalcogenides (TMDC) can be tuned via the metal composition in the TMDC layer. While Gr/MoSe$_2$, has a normal gap, proximity to WSe$_2$ instead leads to valley-Zeeman-driven inverted bands. Although the $\mathbb{Z}_2$ index vanishes, these systems enable a concentration-dependent topological crossover with band gap closure when graphene is stacked on a composite or alloyed TMDC layer. This is due to a nonzero Berry curvature at the individual valleys and a change of the valley Chern index at a critical composition ratio. Therefore, inherently, we also expect that stacked heterostructures of graphene on composite TMDC layers should host localised boundary modes due to the presence of Gr/WSe$_2$- and Gr/MoSe$_2$-like domains with opposite valley Chern indices. In this study, we show that a Gr/(Mo-W)Se$_2$ heterostructure with a lateral interface in the TMDC layer can indeed host topologically protected in-gap propagating modes, similar to those at the border of commensurate AB and BA domains in biased minimally-twisted bilayer graphene. However, the stability of these modes depends crucially on the system size. We demonstrate that the electronic behaviour of Gr/(Mo-W)Se$_2$ heterostructures evolves from a homogeneous effective medium to a superposition of domain-localised bands and zero-energy branch crossings as the domain size in the alloyed TMDC layer is increased.Comment: 10 pages and 4 figure

Outlier Detection and a Method of Adjustment for the Iranian Manufacturing Establishment Survey Data

The role and importance of the industrial sector in the economic development necessitate the need to collect and to analyze accurate and timely data for exact planning. As the occurrence of outliers in establishment surveys are common due to the structure of the economy, the evaluation of survey data by identifying and investigating outliers, prior to the release of data, is necessary. In this paper, different robust multivariate outlier detection methods based on the Mahalanobis distance with blocked adaptive computationally efficient outlier nominators algorithm, minimum volume ellipsoid estimator, minimum covariance determinant estimator and Stahel-Donoho estimator are used in the context of a real dataset. Also some univariate outlier detection methods such as Hadi and Simonoff’s method, and Hidiroglou-Barthelot’s method for periodic manufacturing surveys are applied. The real data set is extracted from the Iranian Manufacturing Establishment Survey. These data are collected each year by the Statistical Center of Iran using sampling weights. In this paper, in addition to comparing different multivariate and univariate robust outlier detection methods, a new empirical method for reducing the effect of outliers based on the value modification method is introduced and applied on some important variables such as input and output. In this paper, a new four-step algorithm is introduced to adjust the input and output values of the manufacturing establishments which are under-reported or over-reported. A simulation study for investigating the performance of our method is also presented

Understanding the antecedents of workplace happiness

This study aims to understand the factors that are predictors of workplace happiness felt by individuals, by looking at the effect of work climate, perceived supervisor support, and perceived organizational support. The research was conducted quantitatively by giving questionnaires to the respondents, namely 185 employees of private companies in the city of Bandung, West Java. The data obtained were then processed using Structural Equation Modeling with SPSS 25 software. The research findings indicate that work climate, perceived supervisor support, and perceived organizational support have a positive effect on workplace happiness, either partially or simultaneously. This research also provides implications and suggestions for future researchers and practitioners in organizations

Distribution of O-Acetylated Sialic Acids among Target Host Tissues for Influenza Virus.

Sialic acids (Sias) are important glycans displayed on the cells and tissues of many different animals and are frequent targets for binding and modification by pathogens, including influenza viruses. Influenza virus hemagglutinins bind Sias during the infection of their normal hosts, while the encoded neuraminidases and/or esterases remove or modify the Sia to allow virion release or to prevent rebinding. Sias naturally occur in a variety of modified forms, and modified Sias can alter influenza virus host tropisms through their altered interactions with the viral glycoproteins. However, the distribution of modified Sia forms and their effects on pathogen-host interactions are still poorly understood. Here we used probes developed from viral Sia-binding proteins to detect O-acetylated (4-O-acetyl, 9-O-acetyl, and 7,9-O-acetyl) Sias displayed on the tissues of some natural or experimental hosts for influenza viruses. These modified Sias showed highly variable displays between the hosts and tissues examined. The 9-O-acetyl (and 7,9-) modified Sia forms were found on cells and tissues of many hosts, including mice, humans, ferrets, guinea pigs, pigs, horses, dogs, as well as in those of ducks and embryonated chicken egg tissues and membranes, although in variable amounts. The 4-O-acetyl Sias were found in the respiratory tissues of fewer animals, being primarily displayed in the horse and guinea pig, but were not detected in humans or pigs. The results suggest that these Sia variants may influence virus tropisms by altering and selecting their cell interactions. IMPORTANCE Sialic acids (Sias) are key glycans that control or modulate many normal cell and tissue functions while also interacting with a variety of pathogens, including many different viruses. Sias are naturally displayed in a variety of different forms, with modifications at several positions that can alter their functional interactions with pathogens. In addition, Sias are often modified or removed by enzymes such as host or pathogen esterases or sialidases (neuraminidases), and Sia modifications can alter those enzymatic activities to impact pathogen infections. Sia chemical diversity in different hosts and tissues likely alters the pathogen-host interactions and influences the outcome of infection. Here we explored the display of 4-O-acetyl, 9-O-acetyl, and 7,9-O-acetyl modified Sia forms in some target tissues for influenza virus infection in mice, humans, birds, guinea pigs, ferrets, swine, horses, and dogs, which encompass many natural and laboratory hosts of those viruses

Shrinkage Estimation of Expression Fold Change As an Alternative to Testing Hypotheses of Equivalent Expression

Research on analyzing microarray data has focused on the problem of identifying differentially expressed genes to the neglect of the problem of how to integrate evidence that a gene is differentially expressed with information on the extent of its differential expression. Consequently, researchers currently prioritize genes for further study either on the basis of volcano plots or, more commonly, according to simple estimates of the fold change after filtering the genes with an arbitrary statistical significance threshold. While the subjective and informal nature of the former practice precludes quantification of its reliability, the latter practice is equivalent to using a hard-threshold estimator of the expression ratio that is not known to perform well in terms of mean-squared error, the sum of estimator variance and squared estimator bias. On the basis of two distinct simulation studies and data from different microarray studies, we systematically compared the performance of several estimators representing both current practice and shrinkage. We find that the threshold-based estimators usually perform worse than the maximum-likelihood estimator (MLE) and they often perform far worse as quantified by estimated mean-squared risk. By contrast, the shrinkage estimators tend to perform as well as or better than the MLE and never much worse than the MLE, as expected from what is known about shrinkage. However, a Bayesian measure of performance based on the prior information that few genes are differentially expressed indicates that hard-threshold estimators perform about as well as the local false discovery rate (FDR), the best of the shrinkage estimators studied. Based on the ability of the latter to leverage information across genes, we conclude that the use of the local-FDR estimator of the fold change instead of informal or threshold-based combinations of statistical tests and non-shrinkage estimators can be expected to substantially improve the reliability of gene prioritization at very little risk of doing so less reliably