333 research outputs found

    Phonon antibunching effect in coupled nonlinear micro/nanomechanical resonator at finite temperature

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    In this study, we investigate the phonon antibunching effect in a coupled nonlinear micro/nanoelectromechanical system (MEMS/NEMS) resonator at a finite temperature. In the weak driving limit, the optimal condition for phonon antibunching is given by solving the stationary Liouville-von Neumann master equation. We show that at low temperature, the phonon antibunching effect occurs in the regime of weak nonlinearity and mechanical coupling, which is confirmed by analytical and numerical solutions. We also find that thermal noise can degrade or even destroy the antibunching effect for different mechanical coupling strengths. Furthermore, a transition from strong antibunching to bunching for phonon correlation has been observed in the temperature domain. Finally, we find that a suitably strong driving in the finite-temperature case would help to preserve an optimal phonon correlation against thermal noise.Comment: 7 pages, 7 figur

    Investigating Employees’ Proactive Extra-Role Information Security Behaviors through Security Mindfulness

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    Connecting mindfulness with organizational information security (InfoSec) is an increasingly attractive research topic. This paper conceptualizes InfoSec mindfulness as a dynamic InfoSec-specific trait evident when handling organizational information assets. We investigate the motivational factors that contribute to InfoSec mindfulness and the effects of InfoSec mindfulness on employees’ proactive extra-role information security behaviors (ISBs), which refers to self-initiated and future-oriented behaviors that go beyond an organization’s information security policies (ISPs) and are independent on rewards or punishments. This paper provides significant theoretical contributions to InfoSec behavioral literature by conceptualizing InfoSec mindfulness and deepening the understanding of proactive extra-role ISBs. We also summarize our research methodology to develop the scale of InfoSec mindfulness and test its validity for our future study

    The Role of Abusive Supervision and Interactional Justice in Employee Information Security Policy Noncompliance Intention

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    Employee information security noncompliance behaviors may ruin an organization’s reputation; thus, much scholarly effort has been devoted to reducing deviating behaviors in organizations. We attempt to determine what motivations may contribute to the formation of an employees’ noncompliance behavioral intentions. The proposed research model links the relationship between abusive supervision and policy noncompliance intention in an information security context. Drawing on organizational justice research, this work explores the role of abusive supervision in employees’ noncompliance with information security policy from an interactional justice perspective and further proposes that the effect of interactional justice on noncompliance intention is moderated by the certainty and severity of sanctions based on general deterrence theory. We present a theoretical foundation for this investigation and an empirical design for exploring this research question. We also propose a plan for a research design and data collection, with results to be presented in the future

    Examining Employee Social Media Deviance: A Psychological Contract Breach Perspective

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    With the prevalence of social media, employees’ deviant behaviors on social media can go viral and result in unpredictable negative outcomes beyond the workplace. This paper investigates the relationship between abusive supervision and employee social media deviance from the theoretical perspective of psychological contract breach (PCB), and examine the moderating role of social media controls. Building on prior studies of abusive supervision and employee workplace deviance, this paper argues that abusive supervision plays a crucial motivational role in triggering employee social media deviance. Our results demonstrate that employees who experience abusive supervision are more likely to perceive PCB, and thus engage in social media deviance. User awareness of social media policy and informal sanctions can weaken the positive relationship between employee perceived PCB and social media deviance

    Efficient Teacher: Semi-Supervised Object Detection for YOLOv5

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    Semi-Supervised Object Detection (SSOD) has been successful in improving the performance of both R-CNN series and anchor-free detectors. However, one-stage anchor-based detectors lack the structure to generate high-quality or flexible pseudo labels, leading to serious inconsistency problems in SSOD. In this paper, we propose the Efficient Teacher framework for scalable and effective one-stage anchor-based SSOD training, consisting of Dense Detector, Pseudo Label Assigner, and Epoch Adaptor. Dense Detector is a baseline model that extends RetinaNet with dense sampling techniques inspired by YOLOv5. The Efficient Teacher framework introduces a novel pseudo label assignment mechanism, named Pseudo Label Assigner, which makes more refined use of pseudo labels from Dense Detector. Epoch Adaptor is a method that enables a stable and efficient end-to-end semi-supervised training schedule for Dense Detector. The Pseudo Label Assigner prevents the occurrence of bias caused by a large number of low-quality pseudo labels that may interfere with the Dense Detector during the student-teacher mutual learning mechanism, and the Epoch Adaptor utilizes domain and distribution adaptation to allow Dense Detector to learn globally distributed consistent features, making the training independent of the proportion of labeled data. Our experiments show that the Efficient Teacher framework achieves state-of-the-art results on VOC, COCO-standard, and COCO-additional using fewer FLOPs than previous methods. To the best of our knowledge, this is the first attempt to apply Semi-Supervised Object Detection to YOLOv5.Comment: 14 page

    Cost- and Energy-Efficient (LED, Induction and Plasma) Roadway Lighting

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    The role of growth directors in controlling the morphology of hematite nanorods

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    The control of the growth of hematite nanoparticles from iron chloride solutions under hydrothermal conditions in the presence of two different structure promoters has been studied using a range of both structural and spectroscopic techniques including the first report of photo induced force microscopy (PiFM) to map the topographic distribution of the structure-directing agents on the developing nanoparticles. We show that the shape of the nanoparticles can be controlled using the concentration of phosphate ions up to a limit determined to be ~6 × 10−3 mol. AkaganĂ©ite (ÎČ-FeOOH) is a major component of the nanoparticles formed in the absence of structure directors but only present in the very early stages (< 8 h) of particle growth when phosphate is present. The PiFM data suggest a correlation between the areas in which phosphate ions are adsorbed and areas where akaganĂ©ite persists on the surface. In contrast, goethite (α-FeOOH) is a directly observed precursor of the hematite nanorods when 1,2-diamino propane is present. The PiFM data shows goethite in the center of the developing particles consistent with a mechanism in which the iron hydroxide re-dissolves and precipitates at the nanorod ends as hematite

    L2hgdh Deficiency Accumulates l-2-Hydroxyglutarate with Progressive Leukoencephalopathy and Neurodegeneration

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    l-2-Hydroxyglutarate aciduria (L-2-HGA) is an autosomal recessive neurometabolic disorder caused by a mutation in the l-2-hydroxyglutarate dehydrogenase (L2HGDH) gene. In this study, we generated L2hgdh knockout (KO) mice and observed a robust increase of l-2-hydroxyglutarate (L-2-HG) levels in multiple tissues. The highest levels of L-2-HG were observed in the brain and testis, with a corresponding increase in histone methylation in these tissues. L2hgdh KO mice exhibit white matter abnormalities, extensive gliosis, microglia-mediated neuroinflammation, and an expansion of oligodendrocyte progenitor cells (OPCs). Moreover, L2hgdh deficiency leads to impaired adult hippocampal neurogenesis and late-onset neurodegeneration in mouse brains. Our data provide in vivo evidence that L2hgdh mutation leads to L-2-HG accumulation, leukoencephalopathy, and neurodegeneration in mice, thereby offering new insights into the pathophysiology of L-2-HGA in humans

    Temporal and Spatial Expression of Muc1 During Implantation in Sows

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    Recent evidence points to an important role for Muc1 in embryo implantation. In this study, Real-time PCR and immunohistochemistry were used to study mRNA and protein levels at, and between, the attachment sites of the endometrium of Day 13, 18 and 24 pregnant sows. The results indicate that Muc1 mRNA expression was higher between attachment sites than at attachment sites during implantation and this effect was significant on Day 13 (P < 0.01) and 24 (P < 0.01). Intense Muc1 immunostaining was observed in luminal epithelium and stroma and the staining between attachment sites was stronger than at attachment sites on Days 13 and 18. Collectively, these results suggest the crucial role of Muc1 in successful implantation and embryo survival

    D-2-hydroxyglutarate is essential for maintaining oncogenic property of mutant IDH-containing cancer cells but dispensable for cell growth

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    Cancer-associated isocitrate dehydrogenase (IDH) 1 and 2 mutations gain a new activity of reducing α-KG to produce D-2-hydroxyglutarate (D-2-HG), which is proposed to function as an oncometabolite by inhibiting α-KG dependent dioxygenases. We investigated the function of D-2-HG in tumorigenesis using IDH1 and IDH2 mutant cancer cell lines. Inhibition of D-2-HG production either by specific deletion of the mutant IDH1-R132C allele or overexpression of D-2-hydroxyglutarate dehydrogenase (D2HGDH) increases α-KG and related metabolites, restores the activity of some α-KG-dependent dioxygenases, and selectively alters gene expression. Ablation of D-2-HG production has no significant effect on cell proliferation and migration, but strongly inhibits anchorage independent growth in vitro and tumor growth in xenografted mouse models. Our study identifies a new activity of oncometabolite D-2-HG in promoting tumorigenesis
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