This paper reported the results of a study that aimed to construct a sensor and handheld augmented reality (AR)‐supported ubiquitous learning (u‐learning) environment called the Handheld English ...Language Learning Organization (HELLO), which is geared towards enhancing students' language learning. The HELLO integrates sensors, AR, ubiquitous computing and information technologies. It is composed of two subsystems: an English learning management system and a u‐learning tool. In order to evaluate the effects of the proposed learning environment on the learning performance of students, a case study on English learning was conducted on a school campus. The participants included high school teachers and students. A learning course entitled ‘My Campus’ was conducted in the class; it included three activities, namely ‘Campus Environment’, ‘Campus Life’ and ‘Campus Story’. The evaluation results showed that the proposed HELLO and the learning activities could improve the students' English listening and speaking skills.
Summary
Porcine reproductive and respiratory syndrome virus (PRRSV) is a major economically significant pathogen that has adversely affected China's swine industry. Currently, a novel type 2 PRRSV, ...called the NADC30‐like strain, is epidemic in numerous provinces of China, and commercial vaccines provide limited protection for infected animals. The extensive recombination phenomenon among NADC30‐like PRRSVs is identified as a unique molecular characteristic of the virus. However, our understanding of how recombination influences NADC30‐like PRRSVs is largely inadequate. In this study, we analysed the genetic characteristics of a recombinant NADC30‐like PRRSV (SC‐d) and examined its pathogenicity compared with a non‐recombinant NADC30‐like PRRSV (SD‐A19) and a highly pathogenic PRRSV (HuN4). SC‐d has three discontinuous deletions in nsp2, consistent with NADC30 isolated from the United States in 2008. Furthermore, we identified four recombination breakpoints in the SC‐d genome, which separated the SC‐d genome into four regions (regions A, B, C and D). Regions A and C are closely related to the JXA1‐like strain, one of the earliest Chinese HP‐PRRSV strains, and regions B and D are closely related to the NADC30 strain. Moreover, SC‐d inoculated piglets exhibited a persistent fever, moderate weight loss, mild thymus atrophy and obvious microscopic lung lesions. In summary, the recombinant NADC30‐like PRRSV SC‐d strain displayed a higher pathogenicity than the non‐recombinant NADC30‐like PRRSV SD‐A19 strain; however, the pathogenicity of the NADC30‐like PRRSV SC‐d was lower compared with the HP‐PRRSV HuN4 strain in piglets. Our findings demonstrate that recombination is responsible for the enormous genetic diversity and pathogenicity variance of the NADC30‐like PRRSV in China. This study provides a theoretical basis for developing a more reasonable PRRSV control and prevention strategy.
The global signal is widely used as a regressor or normalization factor for removing the effects of global variations in the analysis of functional magnetic resonance imaging (fMRI) studies. However, ...there is considerable controversy over its use because of the potential bias that can be introduced when it is applied to the analysis of both task-related and resting-state fMRI studies. In this paper we take a closer look at the global signal, examining in detail the various sources that can contribute to the signal. For the most part, the global signal has been treated as a nuisance term, but there is growing evidence that it may also contain valuable information. We also examine the various ways that the global signal has been used in the analysis of fMRI data, including global signal regression, global signal subtraction, and global signal normalization. Furthermore, we describe new ways for understanding the effects of global signal regression and its relation to the other approaches.
Studies suggest that dysfunction of brain-derived neurotrophic factor (BDNF) is a possible contributor to the pathology and symptoms of Alzheimer's disease (AD). Several studies report reduced ...peripheral blood levels of BDNF in AD, but findings are inconsistent. This study sought to quantitatively summarize the clinical BDNF data in patients with AD and mild cognitive impairment (MCI, a prodromal stage of AD) with a meta-analytical technique. A systematic search of Pubmed, PsycINFO and the Cochrane Library identified 29 articles for inclusion in the meta-analysis. Random-effects meta-analysis showed that patients with AD had significantly decreased baseline peripheral blood levels of BDNF compared with healthy control (HC) subjects (24 studies, Hedges' g=-0.339, 95% confidence interval (CI)=-0.572 to -0.106, P=0.004). MCI subjects showed a trend for decreased BDNF levels compared with HC subjects (14 studies, Hedges' g=-0.201, 95% CI=-0.413 to 0.010, P=0.062). No differences were found between AD and MCI subjects in BDNF levels (11 studies, Hedges' g=0.058, 95% CI=-0.120 to 0.236, P=0.522). Interestingly, the effective sizes and statistical significance improved after excluding studies with reported medication in patients (between AD and HC: 18 studies, Hedges' g=-0.492, P<0.001; between MCI and HC: 11 studies, Hedges' g=-0.339, P=0.003). These results strengthen the clinical evidence that AD or MCI is accompanied by reduced peripheral blood BDNF levels, supporting an association between the decreasing levels of BDNF and the progression of AD.
Abstract
In order to improve the accuracy of architectural decoration engineering evaluation, a new evaluation method based on interactive information model is proposed in this paper. First, the ...paper establishes iim model to complete the evaluation index system of architectural decoration engineering. Then, the weight vectors of the criterion layer and the target layer are determined by the mathematical analytic hierarchy process. Finally, the comprehensive evaluation result of low-carbon Green building design scheme is obtained by calculating the whitening weight function of each gray class. The experimental results show that the method has high accuracy and strong practicability.
Redox‐active anthraquinone molecules represent promising anolyte materials in aqueous organic redox flow batteries (AORFBs). However, the chemical stability issue and corrosion nature of ...anthraquinone‐based anolytes in reported acidic and alkaline AORFBs constitute a roadblock for their practical applications in energy storage. A feasible strategy to overcome these issues is migrating to pH‐neutral conditions and employing soluble AQDS salts. Herein, we report the 9,10‐anthraquinone‐2,7‐disulfonic diammonium salt AQDS(NH4)2, as an anolyte material for pH‐neutral AORFBs with solubility of 1.9 m in water, which is more than 3 times that of the corresponding sodium salt. Paired with an NH4I catholyte, the resulting pH‐neutral AORFB with an energy density of 12.5 Wh L−1 displayed outstanding cycling stability over 300 cycles. Even at the pH‐neutral condition, the AQDS(NH4)2 /NH4I AORFB delivered an impressive energy efficiency of 70.6 % at 60 mA cm−2 and a high power density of 91.5 mW cm−2 at 100 % SOC. The present AQDS(NH4)2 flow battery chemistry opens a new avenue to apply anthraquinone molecules in developing low‐cost and benign pH‐neutral flow batteries for scalable energy storage.
An anthraquinone salt, AQDS(NH4)2, is designed as a new anolyte material for pH‐neutral aqueous organic redox flow batteries (AORFBs) with a solubility of 1.9 m in water. An AORFB using AQDS(NH4)2 delivered outstanding battery performance, including 100 % cycling stability over 300 cycles, an energy efficiency of 70.6 % at 60 mA cm2, and a power density of 91.5 mW cm−2 at 100 % state of charge.
Background Suicide is the third-leading cause of death among adolescents and nonsuicidal self-harm occurs in 13%–45% of individuals within this age group, making these phenomena major public health ...concerns. Lesbian, gay, bisexual, and transgender (LGBT) youth particularly are at risk for engaging in these behaviors. Nevertheless, relatively little is known about the specific risk factors associated with suicidal ideation and self-harm behaviors in the population. Purpose This study provides a longitudinal evaluation of the relative contributions of general and LGBT-specific risk factors as well as protective factors to the occurrence of suicidal ideation and self-harm in an ethnically diverse sample of LGBT youth. Methods A community sample of 246 LGBT youth (aged 16–20 years) was followed prospectively over five time points at regular 6-month intervals. Participants completed a baseline structured interview assessing suicide attempt history and questionnaires measuring gender nonconformity, impulsivity, and sensation-seeking. At follow-up assessments, participants completed a structured interview assessing self-harm and questionnaires for suicidal ideation, hopelessness, social support, and LGBT victimization. Data were collected from 2007 to 2011, and HLM analyses were conducted in 2011. Results A history of attempted suicide ( p =0.05); impulsivity ( p =0.01); and prospective LGBT victimization ( p =0.03) and low social support ( p =0.02) were associated with increased risk for suicidal ideation. Suicide attempt history ( p <0.01); sensation-seeking ( p =0.04); female gender ( p <0.01); childhood gender nonconformity ( p <0.01); and prospective hopelessness ( p <0.01) and victimization ( p <0.01) were associated with greater self-harm. Conclusions General and LGBT-specific risk factors both uniquely contribute to likelihood of suicidal ideation and self-harm in LGBT youth, which may, in part, account for the higher risk of these phenomena observed in this population.
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► Changjiang water level had obvious decrease in the past 10years. ► Thelweg down cutting occurred along the river course downstream from the TDG. ► Suspended sediment flux along ...Changjiang has basically stabilized in the past 10 years. ► The riverbed deposition mode displays strong, intermediate, and weak erosion.
Under the influence of climate and human activities, fluvial systems have natural ability to make adjustments so that the river hydrology, sediment movement, and channel morphology are in dynamic equilibrium. Taking the Changjiang (Yangtze River) for example. In the early stages after the Three Gorges Dam (TGD) began operational ten years ago, the suspended sediment content (SSC) and fluxes in the middle and lower reaches of the river decreased noticeably. At present, they appear to be in a stable state on the decadal scale. Although the river runoff has not shown any trends, the water level in the river decreased appreciably in time. In the meantime, channel down cutting along the thalweg almost existed throughout the river course. The riverbed has turned from depositional before the dam construction to erosional afterwards. In other words, the riverbed had turned from being sediment sinks to sediment sources. In the main channel of the Changjiang between Yichang and Nanjing, a distance of 1300km, the riverbed sedimentation mode displays strong, intermediate, and weak erosion depending on the closeness to the TGD.
Despite the sustained theoretical and empirical interest over the past 40years in the association between life events and suicidal ideation and behavior, the literature in this area has yet to be ...systematically reviewed. The current article provides a comprehensive review of the empirical literature pertaining to life events in relation to at least one aspect of suicidal ideation and behavior (i.e., suicidal ideation, plans, attempts, degree of suicidal intent, medical severity of attempt, repeat versus first lifetime attempt status, and death by suicide). A total of 95 articles meeting inclusion criteria were identified by a literature search using Medline and PsycINFO. Evidence for an association between negative life events and suicidal ideation and behavior was generally consistent, with strongest support found for more severe than with less severe forms of suicidal ideation and behavior. Support for an inverse relation between positive events and suicidal ideation and behavior was generally lacking. Although there is general support for life stressors as a risk factor for suicidal ideation and behavior, interpretation of these findings is constrained by methodological limitations prevalent in much of the literature, particularly in the case of suicidal ideation and suicide plans. Recommendations for future research are provided.
•Provides a systematic review of life events and suicidal ideation and behavior•The relation with stressors was stronger for severe forms of ideation and behavior.•The relation with positive events was weak for suicidal ideation and behavior.•Several important methodological limitations characterize much of the literature.
Providing adaptive features and personalized support by considering students' learning styles in computer‐assisted learning systems has high potential in making learning easier for students in terms ...of reducing their efforts or increasing their performance. In this study, the navigational behaviour of students in an online course within a learning management system was investigated, looking at how students with different learning styles prefer to use and learn in such a course. As a result, several differences in the students' navigation patterns were identified. These findings have several implications for improving adaptivity. First, they showed that students with different learning styles use different strategies to learn and navigate through the course, which can be seen as another argument for providing adaptivity. Second, the findings provided information for extending the adaptive functionality in typical learning management systems. Third, the information about differences in navigational behaviour can contribute towards automatic detection of learning styles, helping in making student modeling approaches more accurate.
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