Purpose-The overload effects associated with the use of mobile information and communication technologies (MICTs) in the workplace have become increasingly prevalent. The purpose of this paper is to examine the overload effects of using MICTs at work on employees' job satisfaction, and explore the corresponding coping strategies. Design/methodology/approach-The study is grounded on the cognitive load theory and the coping model of user adaptation. The overload antecedents and coping strategies are integrated into one model. Theoretical hypotheses are tested with survey data collected from a sample of 178 employees at work in China. Findings-The results indicate that information overload significantly reduces job satisfaction, while the influence of interruption overload on job satisfaction is not significant. Two coping strategies (information processing timeliness and job control assistant support) can significantly improve job satisfaction. Information processing timeliness significantly moderates the relationships between two types of overload effects and job satisfaction. Job control assistant support also significantly moderates the relationship between interruption overload and job satisfaction. Practical implications-This study suggests that information overload and interruption overload could constitute an important index to indicate employees' overload level when using MICTs at work. The two coping strategies provide managers with effective ways to improve employees' job satisfaction. By taking advantage of the moderation effects of coping strategies, managers could lower employees' evaluation of overload to an appropriate level. Originality/value-This study provides a comprehensive model to examine how the overload resulting from using MICTs in the workplace affects employees' work status, and how to cope with it. Two types of overload are conceptualized and corresponding coping strategies are identified. The measurements of principal constructs are developed and empirically validated. The results provide theoretical and practical insights on human resource management and human-computer interaction.

Abstract-As tenants take networked virtual machines (VMs) as their requirements, effective placement of VMs is needed to reduce the network cost in cloud data centers. The cost is one of the major concerns for the cloud providers. In addition to the cost caused by network traffics (N-cost), the cost caused by the utilization of physical machines (PM-cost) is also non-negligible. In this paper, we focus on the optimized placement of VMs to minimize the cost, the combination of N-cost and PM-cost. We define N-cost by various functions, according to different communication models. We formulate the placement problem, and prove it to be NP-hard. We investigate the problem from two aspects. Firstly, we put a special emphasis on minimizing the Ncost with fixed PM-cost. For the case that tenants request the same amount of VMs, we present optimal algorithms under various definitions of N-cost. For the case that tenants require different numbers of VMs, we propose an approximation algorithm. Also, a greedy algorithm is implemented as the baseline to evaluate the performance. Secondly, we study the general case of the VM placement problem, in which both N-cost and PM-cost are taken into account. We present an effective binary-searchbased algorithm to determine how many PMs should be used, which makes a tradeoff between PM-cost and N-cost. For all of the algorithms, we conduct theoretical analysis and extensive simulations to evaluate their performance and efficiency.

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Aeromonas species are indigenous in diverse aquatic environments and play important roles in environmental remediation. However, the pollutant transformation mechanisms of these bacteria remain elusive, and their potential in pollution control is largely unexploited so far. In this work, we report an efficient and simple genome regulation tool to edit Aeromonas hydrophila and identify its biomolecular pathways for pollutant transformation. The genome regulation system, which is based on the type II clustered regularly interspaced short palindromic repeat interference (CRISPRi) system from Streptococcus pyogenes, can serve as a reversible and multiplexible platform for gene knockdown in A. hydrophila. A single-plasmid CRISPRi system harboring both dCas9 and the sgRNA was constructed in A. hydrophila and used to silence diverse genes with varied sizes and expression levels. With this system, up to 467-fold repression of gfp expression was achieved, and the function of the essential gene-ftsZ was identified quickly and accurately. Furthermore, simultaneous transcriptional repression of multiple targeted genes was realized. We discovered that the ars operon played an essential role in arsenic detoxification, and the extracellular electron transfer (EET) pathway was involved in methyl orange reduction, but not in vanadium reduction by A. hydrophila. Our method allows better insights and effective genetic manipulation of the pollutant transformation processes in Aeromonas, which might facilitate more efficient utilization of the Aeromonas species and other microbial species for environmental remediation applications.

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Plastics–microorganism interactions have aroused growing environmental and ecological concerns. However, previous studies concentrated mainly on the direct interactions and paid little attention to the ecotoxicology effects of phthalates (PAEs), a common plastic additive that is continuously released and accumulates in the environment. Here, we provide insights into the impacts of PAEs on the dissemination of antibiotic resistance genes (ARGs) among environmental microorganisms. Dimethyl phthalate (DMP, a model PAE) at environmentally relevant concentrations (2–50 μg/L) significantly boosted the plasmid-mediated conjugation transfer of ARGs among intrageneric, intergeneric, and wastewater microbiota by up to 3.82, 4.96, and 4.77 times, respectively. The experimental and molecular dynamics simulation results unveil a strong interaction between the DMP molecules and phosphatidylcholine bilayer of the cell membrane, which lowers the membrane lipid fluidity and increases the membrane permeability to favor transfer of ARGs. In addition, the increased reactive oxygen species generation and conjugation-associated gene overexpression under DMP stress also contribute to the increased gene transfer. This study provides fundamental knowledge of the PAE–bacteria interactions to broaden our understanding of the environmental and ecological risks of plastics, especially in niches with colonized microbes, and to guide the control of ARG environmental spreading.