Polymer/cement composites have gained significant attention in civil engineering due to their improved properties compared to traditional cement-based materials ....
PurposeThe purpose of this paper is to investigate the association between abusive supervision and employees' information security policy (ISP) noncompliance intention, building on affective ...commitment, normative commitment and continuance commitment. The study also examines the moderating effect of perceived certainty and severity of sanctions on the relationship between the three dimensions of organizational commitment and ISP noncompliance intention.Design/methodology/approachSurvey methodology was used for data collection through a well-designed online questionnaire. Data was analyzed using the structural equation model with Amos v. 22.0 software.FindingsThis study demonstrates that abusive supervision has a significant, negative impact on affective, normative and continuance commitment, and the three dimensions of organizational commitment are negatively associated with employees' ISP noncompliance intention. Results also indicate that the moderating effect of perceived severity of sanctions is significant, and perceived certainty of sanctions plays a positive moderating role in the relationship between affective commitment and employees' ISP noncompliance intention.Practical implicationsFindings of this research are beneficial for organizational management in the relationships between supervisors and employees. These results provide significant evidence that avoiding abusive supervision is important in controlling employees' ISP noncompliance behavior.Originality/valueThis research fills an important gap in examining employees' ISP noncompliance intentions from the perspective of abusive supervision and the impact of affective, normative and continuance commitment on ISP noncompliance. The study is also of great value for information systems research to examine the moderating role of perceived certainty and severity of sanctions.
Images captured in underwater environments often suffer from color distortion, low contrast, and reduced visual quality. Most existing methods solve underwater image enhancement (UIE) by applying ...supervised training on synthetic images or pseudo references. However, the synthetic paired data fail to accurately replicate real-world data due to the inherent differences, and the quantity and quality of pseudo references are limited, which seriously reduces the generalization ability and performance of the model when testing on real underwater images. In contrast, unsupervised-based method is not constrained by paired data, which is more robust and potentially more promising for practical applications. Nevertheless, existing unsupervised-based methods cannot effectively constrain the network to train a model that can adapt to various degradation. Inspired by the fact that people often resolve problems from opposing but complementary perspectives, we maintain that there is implicit cooperation between the removal and generation of water layers, as they can constrain and promote each other at the same time. Based on the above analysis, a new unsupervised-based UIE framework that jointly learns water layer generation and removal based on disentangled representations is proposed. Specifically, we propose a bidirectional disentangling network in which each unidirectional network contains a loop consisting of water layer removal and generation, and restricts the image to remain consistent after a loop. Meanwhile, a novel double-order contrastive loss is proposed to improve the ability of disentanglement by utilizing the joint implicit constraint of first-order features and second-order features. Extensive experimental results demonstrate that the model outperforms the state-of-the-art methods in both qualitative and quantitative evaluation with a relatively high processing speed. The experimental results of the ablation study demonstrate the usefulness of the various components.
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•On-site performance of a desiccant-wheel deep-dehumidification system is analyzed.•The adoption of the high-cost electric heater for regeneration limits the COPsys.•A refined system ...is proposed to improve the system energy performance.•The COPsys can be improved from 0.65 to 0.68 to 0.76–0.79 by the refined system.
Desiccant wheel system is a feasible system to meet the deep-dehumidification demand of dehumidifying air to below 6 g/kg, which has been widely used in industrial environments. On-site performance can reflect real performance of the system in practical applications. However, limited studies have conducted measurements to reveal the on-site performance of the desiccant wheel deep-dehumidification (DWDD) system. Thus, in this study, measurements are conducted to reveal the on-site performance of a DWDD system applied in a lithium battery manufacturing plant, and then simulations are performed to improve the system performance. The test results reveal that the system coefficient of performance (COPsys) ranges 0.65–0.68 under the typical summer climate in Jiangsu Province of China. For equipment space and safety reasons, the electric heater is the only viable heating source type for regeneration in this plant. Accordingly, the dehumidificaiton cost of the desiccant wheel is significantly higher than that of the cooler, which limits the COPsys of the current system. Furthermore, a refined system is proposed to improve the system energy performance. Simulation results demonstrate that the COPsys can be improved from 0.65 to 0.68 to 0.76–0.79 by avoiding the secondary return air design. During the entire cooling season, an electricity saving rate of 8.4% can be achieved by the refined system. This study provides a reference for the DWDD system design under limitations in practical applications.
Abstract
Radiation-induced pulmonary fibrosis (RIPF) is a late toxicity of therapeutic radiation in clinic with poor prognosis and limited therapeutic options. Previous results have shown that ...senescent cells, such as fibroblast and type II airway epithelial cell, are strongly implicated in pathology of RIPF. However, the role of senescent macrophages in the development RIPF is still unknown. In this study, we report that ionizing radiation (IR) increase cellular senescence with higher expression of senescence-associated β-galactosidase (SA-β-Gal) and senescence-specific genes (p16, p21, Bcl-2, and Bcl-xl) in irradiated bone marrow-derived monocytes/macrophages (BMMs). Besides, there’s a significant increase in the expression of pro-fibrogenic factors (TGF-β1 and Arg-1), senescence-associated secretory phenotype (SASP) proinflammatory factors (Il-1α, Il-6, and Tnf-α), SASP chemokines (Ccl2, Cxcl10, and Ccl17), and SASP matrix metalloproteinases (Mmp2, Mmp9 and Mmp12) in BMMs exposed to 10 Gy IR. In addition, the percentages of SA-β-Gal
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senescent macrophages are significantly increased in the macrophages of murine irradiated lung tissue. Moreover, robustly elevated expression of p16, SASP chemokines (Ccl2, Cxcl10, and Ccl17) and SASP matrix metalloproteinases (Mmp2, Mmp9, and Mmp12) is observed in the macrophages of irradiated lung, which might stimulate a fibrotic phenotype in pulmonary fibroblasts. In summary, irradiation can induce macrophage senescence, and increase the secretion of SASP in senescent macrophages. Our findings provide important evidence that senescent macrophages might be the target for prevention and treatment of RIPF.
In order to evaluate the macro-mechanical performance of asphalt mixture suffered from the sulphate-water-temperature-load coupling action, the self-designed asphalt mixture dynamic water-salt attack ...apparatus was adopted for the accelerated simulation of real service conditions in sulphate enrichment environment. Splitting test at room temperature and low temperature was conducted for assessing the performance of asphalt mixture suffered from still water immersion and multi-factor coupling action. Then the performance damage characteristics of asphalt mixture under different conditions were explored. The multi-linear regression analysis and t-test were applied to determine the significance of factors on the performance of asphalt mixture. The performance deterioration mechanism of asphalt mixture exposed to dynamic water and sulphate attack was preliminarily analysed. The results show that the sulphate-water-temperature-load coupling action plays an important role in the macro-mechanical performance deterioration of asphalt mixture and dynamic water further accelerates the deterioration process of sulphate attack to asphalt mixture. The dynamic water scouring times, temperature and sulphate solution concentration have a significant impact on the performance of asphalt mixture. The decreasing adhesion between asphalt and aggregate, along with exterior/interior sulphate crystallisation erosion contributes the important inducement for the performance deterioration of asphalt mixture.
The performance of an asphalt mixture will deteriorate under the condition of salt erosion, but there are different opinions on the mechanism of deterioration. Few studies have focused on the ...relation between the change of void characteristics and performance deterioration of an asphalt mixture exposed to salt erosion. To explore the relation between the air voids characteristics of an asphalt mixture and mechanical damage under salt erosion, the mechanical damage in an asphalt mixture was measured by splitting strength. The asphalt mixture specimens, immersion solutions, asphalt mortar, and aggregate were scanned with CT technology. To segment the voids, the Otsu method was used over asphalt mortar and solution range of CT values. A three-dimensional reconstruction of the CT image was performed with Mimics 20 software to calculate the asphalt mixture's void characteristics. On this basis, the relationships between the change in void characteristics and splitting strength were analyzed. The results showed that the ideal calculated void fraction can be obtained by threshold segmentation of the image void/asphalt mortar interface with the local CT value Otsu method. Under the salt corrosion environment, the increase of open voids of an asphalt mixture is linearly correlated with the decrease of splitting strength, while salts' crystallization in the open voids produces crystallization pressure, accelerating the volume growth of open voids. The early damage of an asphalt mixture suffered from the salt may be mainly physical damage. These results can provide a useful reference for the performance of damage research on asphalt mixtures in salt enrichment areas.
To solve the problem of the poor abrasion resistance of concrete pavement surface mortar, this study substituted cement with equal amounts of styrene-butadiene rubber (SBR) latex and silica fume (SF) ...to investigate the effects of organic/inorganic material composite modification on the fluidity, drying shrinkage, mechanical properties, and abrasion resistance of cement mortar. Also in this study, the microstructure, product, and pore structure characteristics of the composite modified cement mortar were investigated using scanning electron microscope (SEM), X-Ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and the Brunauer-Emmett-Teller (BET) method. This research found that the sole substitution of SF negatively impacted the mortar's fluidity and drying shrinkage yet enhanced its mechanical strength and abrasion resistance; the incorporation of SBR latex improved fluidity, reduced shrinkage, and increased flexural strength but adversely affected the compressive strength of the mortar. Additionally, the enhancement of the mortar's abrasion resistance with SBR latex was significantly greater than that with SF. When SBR latex and SF were used together as substitutes, the latex struggled to offset the negative impact of SF on mortar fluidity but effectively reduced shrinkage; SF compensated for the detrimental effect of the latex on compressive strength. Moreover, the primary role in enhancing the mortar's abrasion resistance was played by the latex. Microscopic tests showed that SBR latex and SF could increase the content of calcium silicate hydrate (C-S-H) gel, inhibit the formation of ettringite (AFt) and reduce carbonation, refine the pore size of cement mortar, and effectively improve the microstructure of mortar.
The application of magnesium oxychloride cement (MOC) is promising, but its poor water resistance seriously hinders its development and application. In this paper, we describe a new type of MOC with ...excellent water resistance, prepared using fly ash and hexadecyltrimethoxysilane (HDTMS). SEM, XRD, FTIR, TG/DSC, and other microscopic-scale studies were conducted to investigate the mechanism underlying the water-resistance enhancement of the new MOC. It was found that adding 20% fly ash and 3% HDTMS can strengthen the water resistance of MOC while retaining high mechanical properties. In particular, the residual coefficient remained at 0.91 after 7 days of immersion. This is because these two additives, when used together, can increase the content of the gelling 5-phase of MOC, as well as optimize the pore structure of MOC.
Abstract
The risk of internal and external exposure to ionizing radiation (IR) has increased alongside the development and implementation of nuclear technology. Therefore, serious security issues ...have emerged globally, and there has been an increase in the number of studies focusing on radiological prevention and medical countermeasures. Radioprotective drugs are particularly important components of emergency medical preparedness strategies for the clinical management of IR‐induced injuries. However, a few drugs have been approved to date to treat such injuries, and the related mechanisms are not entirely understood. Thus, the aim of the present review was to provide a brief overview of the World Health Organization's updated list of essential medicines for 2023 for the proper management of national stockpiles and the treatment of radiological emergencies. This review also discusses the types of radiation‐induced health injuries and the related mechanisms, as well as the development of various radioprotective agents, including Chinese herbal medicines, for which significant survival benefits have been demonstrated in animal models of acute radiation syndrome.
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