11,890 research outputs found

    Comparison of two nicotine dependence measures for use with Korean American Women: The FTND and AUTOS

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    This study compares psychometric properties of the Fagerström Test for Nicotine Dependence (FTND) and Autonomy over Tobacco Scale (AUTOS), which are measures of nicotine dependence. This study is a secondary analysis of data obtained from a smoking cessation study conducted with 49 Korean American women. We compared the FTND and AUTOS assessed at baseline regarding their internal consistency reliability and concurrent and predictive validities. The AUTOS outperformed the FTND in reliability and concurrent validity by yielding a higher Cronbach’s alpha and having significant relationships with smoking-related variables such as age at smoking onset, perceived risks of quitting, and self-efficacy in quitting. In contrast, there was no relationship between the FTND and any of the variables. Both measures had a significant relationship with post-quit nicotine withdrawal symptoms but failed to predict abstinence at follow-ups. The AUTOS seems to be a better assessment tool for Korean American women than the FTND. Before fully adopting the AUTOS as a measure of nicotine dependence for this group, factor structure of the scale should be tested with a larger sample of Korean American women

    Unique Appearance of Lamellar Cleavage Patterns on Fracture Surfaces of Ti-Based Amorphous Matrix Composite

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    In order to improve mechanical properties of Ti-based amorphous matrix composites basically composed of ductile beta-Ti dendrites and brittle amorphous matrix by overcoming their inherent brittle nature, their fracture mechanisms should be verified in relation with microstructure, stress intensity factor level, and crack growth rate. In this study, thus, detailed fractographic observations including the unique appearance of lamellar cleavage patterns, which has not been reported in previous studies on conventional metals and alloys, were conducted. According to fractographic results, lamellar cleavage patterns were formed by repeated interruptions of crack propagation on {100} cleavage planes by difference between dendrite orientation and loading direction. Ductile-to-brittle transition phenomenon (ductile dimpled fracture -> lamellar cleavage fracture -> ordinary cleavage fracture in dendrite areas, and vein pattern -> smooth pattern in amorphous matrix areas) occurred with increasing crack growth rate was also plausibly explained by the concept of time required for crack growth as well as dendrite orientation.open1122sciescopu

    Twinning-mediated formability in Mg alloys

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    Mg alloys are promising candidates for automotive applications due to their low density and high specific strength. However, their widespread applications have not been realized mainly because of poor formability at room temperature, arising from limited number of active deformation systems and strong basal texture. It has been recently shown that Mg-Zn-Ca alloys have excellent stretch formability, which has been ascribed to their weak basal texture. However, the distribution of basal poles is orthotropic, which might result in anisotropy during deformation and have adverse effect on formability. Here, we show that tension twinning is mainly responsible for enhanced formability of Mg-Zn-Ca alloys. We found that tension twinning is quite active during both uniaxial deformation and biaxial deformation of Mg-Zn-Ca alloy even under the stress conditions unfavourable for the formation of tensile twins. Our results provide new insights into the development of Mg alloys having high formability.112514Ysciescopu

    High strength and formable Mg-6.2Zn-0.5Zr-0.2Ca alloy sheet processed by twin roll casting

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    Twin roll cast and hot rolled Mg-6.2 wt%Zn alloys microalloyed with Zr, Ca, and Ag show tensile yield strength exceeding 300 MPa in the T6 (peak-aged) condition with reasonable formability in the T4 condition. The addition of Zr and Ca plays a critical role in the development of weak textured recrystallized microstructure in Mg-6.2 wt%Zn alloys so Mg-6.2Zn-0.5Zr-0.2Ca (wt%) alloy shows equivalent mechanical properties with Mg-6.2Zn-0.5Zr-0.2Ca-0.4Ag (wt%) alloy even without expensive Ag. (C) 2014 Elsevier B.V. All rights reserved.X112224Ysciescopu

    Finite element analysis for normal pressure hydrocephalus: The effects of the integration of sulci.

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    Finite element analysis (FEA) is increasingly used to investigate the brain under various pathological changes. Although FEA has been used to study hydrocephalus for decades, previous studies have primarily focused on ventriculomegaly. The present study aimed to investigate the pathologic changes regarding sulcal deformation in normal pressure hydrocephalus (NPH). Two finite element (FE) models-an anatomical brain geometric (ABG) model and the conventional simplified brain geometric (SBG) model-of NPH were constructed. The models were constructed with identical boundary conditions but with different geometries. The ABG model contained details of the sulci geometry, whereas these details were omitted from the SBG model. The resulting pathologic changes were assessed via four biomechanical parameters: pore pressure, von Mises stress, pressure, and void ratio. NPH was induced by increasing the transmantle pressure gradient (TPG) from 0 to a maximum of 2.0 mmHg. Both models successfully simulated the major features of NPH (i.e., ventriculomegaly and periventricular lucency). The changes in the biomechanical parameters with increasing TPG were similar between the models. However, the SBG model underestimated the degree of stress across the cerebral mantle by 150% compared with the ABG model. The SBG model also overestimates the degree of ventriculomegaly (increases of 194.5% and 154.1% at TPG = 2.0 mmHg for the SBG and ABG models, respectively). Including the sulci geometry in a FEA for NPH clearly affects the overall results. The conventional SBG model is inferior to the ABG model, which accurately simulated sulcal deformation and the consequent effects on cortical or subcortical structures. The inclusion of sulci in future FEA for the brain is strongly advised, especially for models used to investigate space-occupying lesions.This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (2013R1A1A1004827).This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.media.2015.05.00

    Resonances in an external field: the 1+1 dimensional case

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    Using non-relativistic effective field theory in 1+1 dimensions, we generalize Luescher's approach for resonances in the presence of an external field. This generalized approach provides a framework to study the infinite-volume limit of the form factor of a resonance determined in lattice simulations.Comment: 13 pages, 2 postscript figure

    Exploring Consumers’ Attitudes of Smart TV Related Privacy Risks

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    A number of privacy risks are inherent in the Smart TV ecosystem. It is likely that many consumers are unaware of these privacy risks. Alternatively, they might be aware but consider the privacy risks acceptable. In order to explore this, we carried out an online survey with 200 participants to determine whether consumers were aware of Smart TV related privacy risks. The responses revealed a meagre level of awareness. We also explored consumers’ attitudes towards specific Smart TV related privacy risks. We isolated a number of factors that influenced rankings and used these to develop awareness-raising messages. We tested these messages in an online survey with 155 participants. The main finding was that participants were generally unwilling to disconnect their Smart TVs from the Internet because they valued the Smart TV’s Internet functionality more than their privacy. We subsequently evaluated the awareness-raising messages in a second survey with 169 participants, framing the question differently. We asked participants to choose between five different Smart TV Internet connection options, two of which retained functionality but entailed expending time and/or effort to preserve privacy

    SUMO-Specific Protease 2 (SENP2) Is an Important Regulator of Fatty Acid Metabolism in Skeletal Muscle

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    Small ubiquitin-like modifier (SUMO)-specific proteases (SENPs) that reverse protein modification by SUMO are involved in the control of numerous cellular processes, including transcription, cell division, and cancer development. However, the physiological function of SENPs in energy metabolism remains unclear. Here, we investigated the role of SENP2 in fatty acid metabolism in C2C12 myotubes and in vivo. In C2C12 myotubes, treatment with saturated fatty acids, like palmitate, led to nuclear factor-B-mediated increase in the expression of SENP2. This increase promoted the recruitment of peroxisome proliferator-activated receptor (PPAR) and PPAR, through desumoylation of PPARs, to the promoters of the genes involved in fatty acid oxidation (FAO), such as carnitine-palmitoyl transferase-1 (CPT1b) and long-chain acyl-CoA synthetase 1 (ACSL1). In addition, SENP2 overexpression substantially increased FAO in C2C12 myotubes. Consistent with the cell culture system, muscle-specific SENP2 overexpression led to a marked increase in the mRNA levels of CPT1b and ACSL1 and thereby in FAO in the skeletal muscle, which ultimately alleviated high-fat diet-induced obesity and insulin resistance. Collectively, these data identify SENP2 as an important regulator of fatty acid metabolism in skeletal muscle and further implicate that muscle SENP2 could be a novel therapeutic target for the treatment of obesity-linked metabolic disorders.11116Ysciescopu

    General Gauge Mediation at the Weak Scale

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    We completely characterize General Gauge Mediation (GGM) at the weak scale by solving all IR constraints over the full parameter space. This is made possible through a combination of numerical and analytical methods, based on a set of algebraic relations among the IR soft masses derived from the GGM boundary conditions in the UV. We show how tensions between just a few constraints determine the boundaries of the parameter space: electroweak symmetry breaking (EWSB), the Higgs mass, slepton tachyons, and left-handed stop/sbottom tachyons. While these constraints allow the left-handed squarks to be arbitrarily light, they place strong lower bounds on all of the right-handed squarks. Meanwhile, light EW superpartners are generic throughout much of the parameter space. This is especially the case at lower messenger scales, where a positive threshold correction to mhm_h coming from light Higgsinos and winos is essential in order to satisfy the Higgs mass constraint.Comment: 43 pages, 20 figures, mathematica package included in the sourc
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