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Cu-based catalysts with abundant oxygen vacancies have attracted great attention for the reverse water–gas shift (RWGS) reaction because of their enhanced activity for CO2adsorption and activation. However, the effect of the oxygen vacancy origin on the reaction and mechanism of RWGS are still unclear. Herein, various Cu/CeyZr1–yOxcatalysts with different Ce/Zr ratios were designed and used for RWGS, and the results showed that the Cu/Ce0.9Zr0.1Oxcatalyst exhibited the highest CO2conversion (57.5%) and 100% CO selectivity. The characterization showed that Cu/Ce0.9Zr0.1Oxpossessed highly dispersed Cu, abundant oxygen vacancies, and optimized basic sites, and the synergistic effect of the three factors led to the highest activity and stability. Both formate and carbonate pathways have been confirmed for Cu/CeyZr1–yOx, while the dominant reaction path is different between Cu/ZrO2and Cu/CeO2.

Aim: High screen time and smartphone multitasking are ever-increasing phenomena among children and adolescents, which cause growing concern regarding potential impacts on mental health. The purpose of this study was to examine the relationship between weekday/weekend screen time, smartphone multitasking, and mental health. Subject and methods: A total of 4024 students free of certain physical disease and mental disorders (aged 11–23 years) participated in this cross-sectional study. The Brief Instrument on Psychological Health of Youths (BIOPHY) was administered to assess psychological health. Apart from screen time, college students were requested to complete questionnaires on smartphone multitasking. Logistic regression analyses were used to examine the relationship between screen time/different types of smartphone multitasking activities and mental health. Results: Of the participants, 29.52% and 66.40% were classified as high screen time (>2 h/d) on weekdays and weekends, respectively, and 14.34% exhibited mental health problems. High screen time (versus ≤2 h/d) was significantly associated with higher odds of having mental health problems after adjusting for confounders. Furthermore, the effects were larger for weekdays (OR= 1.71; 95% CI1.36–2.15) compared to weekends (OR= 1.32; 95% CI1.07–1.61). There was also a trend toward significance for more frequent smartphone multitasking (including nonmedia, cross-media, and single-device multitasking) to be associated with a higher prevalence of mental health problems for college students. Conclusion: Arranging screen time reasonably and understanding smartphone multitasking correctly may be important for preventing psychological health problems for children and adolescents.

Vortex electromagnetic radar can achieve high-resolution imaging according to the approximate dual relationship between orbital angular momentum (OAM) mode variable and target azimuth variable. The azimuth resolution is determined by the number of OAM modes, which is limited in radar systems. In addition, the inconsistent pointing of the vortex beam carrying different OAM modes limits the echo energy, further influencing the azimuth resolution. However, existing research has not comprehensively considered the impact of the number of OAM modes and beam pointing on imaging performance, making it difficult to obtain high-resolution images using a few suitable OAM modes and hard to allocate radar resources for multitarget imaging reasonably. To solve the above problems, a new vortex electromagnetic radar imaging and adaptive resource scheduling method based on uniform concentric circular arrays (UCCA) is proposed in this article. First, a 2-D sparse imaging method based on UCCA with stepped frequency chirp signal (SFCS) is proposed, where the joint selection of array number and OAM modes is accomplished with the beam pointing modulated by different array radii. By this method, target imaging can be achieved with a small number of OAM modes and SFCS sub-pulses. On this basis, according to the prior target feature information, an adaptive resource scheduling optimization model is established for multitarget imaging, and a corresponding two-step solution method is proposed. As a result, array, OAM mode, and frequency resources can be reasonably allocated among targets, and high-resolution images can be obtained. The effectiveness of the proposed method is demonstrated by simulations.

Dry powder inhaler (DPI) products are commonly formulated as a mixture of micronized drug particles and large carrier particles, with or without additional fine particle excipients, followed by final powder filling into dose containment systems such as capsules, blisters, or reservoirs. DPI product manufacturing consists of a series of unit operations, including particle size reduction, blending, and filling. This review provides an overview of the relevant critical process parameters used for jet milling, high-shear blending, and dosator/drum capsule filling operations across commonly utilized instruments. Further, this review describes the recent achievements regarding the application of empirical and mechanistic models, especially discrete element method (DEM) simulation, in DPI process development. Although to date only limited modeling/simulation work has been accomplished, in the authors’ perspective, process design and development are destined to be more modeling/simulation driven with the emphasis on evaluating the impact of material attributes/process parameters on process performance. The advancement of computational power is expected to enable modeling/simulation approaches to tackle more complex problems with better accuracy when dealing with real-world DPI process operations.

The advances and challenges of power-to-methane, especially the methanation process, including operation parameters, catalyst categories and roles, and reaction/deactivation mechanisms, are discussed in detail.

Due to its higher data density, longevity, energy efficiency, and ease of generating copies, DNA is considered a promising technology for satisfying future storage needs. However, a diverse set of errors including deletions, insertions, duplications, and substitutions may arise in DNA at different stages of data storage and retrieval. The current paper constructs error-correcting codes for simultaneously correcting short (tandem) duplications and at most $p$ edits, where a short duplication generates a copy of a substring with length $\leq 3$ and inserts the copy following the original substring, and an edit is a substitution, deletion, or insertion. Compared to the state-of-the-art codes for duplications only, the proposed codes correct up to $p$ edits (in addition to duplications) at the additional cost of roughly $8p(\log _{q} n) (1+o(1))$ symbols of redundancy, thus achieving the same asymptotic rate, where $q\ge 4$ is the alphabet size and $p$ is a constant. Furthermore, the time complexities of both the encoding and decoding processes are polynomial when $p$ is a constant with respect to the code length.

In the tasks of image aesthetic quality assessment, it is difficult to reach both the high score area and low score area due to the normal distribution of aesthetic datasets. To reduce the error in labelling and solve the problem of normal data distribution, we propose a new aesthetic mixed dataset with classification and regression called AMD-CR, and we train a meta reweighting network to reweight the loss of training data differently. In addition, we provide a training strategy according to different stages based on pseudo labels, and then we use it for aesthetic training according to different stages in classification and regression tasks. In the construction of the network structure, we construct an aesthetic adaptive block (AAB) structure that can adapt to any size of the input images. Besides, we also use the efficient channel attention (ECA) to strengthen the feature extracting ability of each task. The experimental result shows that our method improves 0.1112 compared with the conventional method in SROCC. The method can also help to find best aesthetic path planning for unmanned aerial vehicles (UAV) and vehicles.

This study investigates antecedents to and outcomes of two stress reactions, telework distress (detrimental stress), and telework eustress (beneficial stress) using a model derived from an integration of the transactional model of stress with the job-demands and resources model. The model includes a person antecedent (resilience), and three environment antecedents (work-family conflict, work overload, and autonomy). These factors should influence experienced distress and eustress, which, in turn, affect telework outcomes (telework satisfaction, exhaustion, perceived performance, and perceived productivity. The model is evaluated using a sample of 329 Chinese teleworkers. This study findings indicate that resilience, work-family conflict, and work overload affect experienced distress, while resilience and autonomy affect experienced eustress. Experienced distress influenced satisfaction, exhaustion, and perceived performance; eustress had effects on all four outcomes. Interestingly, resilience had the largest total effect sizes on telework outcomes.

There are many tasks on image aesthetic assessment, such as aesthetic classification, scoring, score distribution prediction, and captions. Due to the distribution of the aesthetic score is unbalanced, the assessment models always output scores near the mean score. In this paper, we propose a fine-grained regression method for aesthetics score regression and combine position and channel attention mechanisms to enhance the aesthetic feature fusion. And by training the regression network separately from the classification network, we make the classification task a complement to the regression task. Besides, the researchers are used to using Mean Square Error (MSE) as the main evaluation metric which is inadequate in measuring the error of each interval. In order to fully consider the images of the various aesthetic score segments, instead of focusing on the intermediate aesthetic score segments because of the imbalance of the aesthetic datasets, we propose a new evaluation metric called Segmented Mean Square Errors (SMSE) to prove the advantages of the model. We divide the entire AADB dataset into 10 equal parts based on the aesthetic scores and the experiments were carried out on each of the segmented AADB datasets. In this way, images for each aesthetic score segment are fairly considered. The experimental results reveal that our method outperforms all the state-of-the-art methods on both MSE and SMSE. The dual attention modules of position and channel also make the activation maps more reasonable. Our methods make the aesthetic scoring go beyond laboratories to real life applications. Because computational visual aesthetics is a very interesting and challenging task in the field of computer vision, and computer vision is also one of the key areas of focus of this journal, the method proposed in this paper is closely related to the field covered by the journal.

This study aimed to investigate the diffusivities of lysozyme (LYS), ovalbumin (OVA), and hyaluronic acid (HA) in buffered solvents using dynamic light scattering (DLS). For protein/solvent and HA/solvent binary systems, the diffusion coefficients of protein or HA were obtained from autocorrelation function (ACF) curve fitting. Whereas, for protein/HA/solvent ternary systems, the two eigenvalues of the mutual diffusion coefficient matrix were obtained from ACF curve fitting. The results of binary systems showed that at low ionic strength, the diffusion coefficients of protein and HA increased linearly with concentration; at high ionic strength, the diffusion coefficients of OVA and LYS were independent on protein concentration; for HA, the positive linear relationship between diffusion coefficient and concentration existed at high and low ionic strengths, but the slope at high ionic strength was smaller compared to that at low ionic strength. For OVA/HA/solvent ternary systems, the sum of two eigenvalues (D1DLS+ D2DLS) was slightly smaller compared to (DOVA+ DHA), where DOVAand DHAwere the diffusion coefficients in their binary systems. On the contrary, for LYS/HA/solvent ternary systems, (D1DLS+ D2DLS) were significantly smaller than (DLYS+ DHA) and the diffusion coefficients in binary and ternary systems exhibited an opposite trend with respect to ionic strength change. The DLS and MD simulation results indicated strong attractive intermolecular interaction existed between LYS and HA molecules, especially at low ionic strength. By using DLS, it was possible to characterize the diffusion coefficients of diluted protein/HA binary and ternary systems.

ABSTRACT Groupware technologies have become an important part of the business computing and communicating infrastructure in many organizations. However, literature suggests that many groupware applications, especially those requiring significant collaboration […]

This case study reports findings on user acceptance of an electronic mail system in a business college setting. It builds on earlier research of computer-mediated communication systems by Hiltz and Johnson (1989). Although the use of the electronic mail system is mandatory in this organization, the overall results are parallel to earlier findings in terms of usage, satisfaction with, and perceived outcomes of the system. In contrast to a contention of earlier research, the current results suggest that mandatory use of electronic mail can be an appropriate strategy for implementing such systems in organizations.

To better understand how humor is used in today's multicultural virtual environment, this study investigates the humor styles of Hispanic Americans in a virtual community. Based on the four humor styles, the current study builds a theoretical framework to explain why cultural norms, gender role, acculturation, and education influence the humor styles of Hispanic Americans in computer-mediated communication. Two research questions and five hypotheses are developed in the research framework. The statistical analysis is based on content analysis of 400 Hispanic Facebook users, 93 of whom use humor in most recent News Feed. The results provide preliminary evidence of the influences of cultural norms, gender role, acculturation, and education on Hispanic humor styles.

The combined influence of Mg and Ca treatment on the properties of heat-affected zone (HAZ) of low-carbon steel after high heat input welding was systematically studied. Experimental steels deoxidized with different elements were prepared, i.e., C–Mn steel with Al, Ti–Ca steel with Ti and Ca, Ti–Mg–Ca steel with Ti, Mg and Ca. Results showed that the inclusions in C–Mn steel were mainly Al2O3and MnS with low density and large size. However, the average size was refined to only ~ 0.34 μm in Ti–Mg–Ca steel and the amount increased remarkably. Microstructure of simulated HAZ for 200 kJ/cm changed from ferrite side plates or upper bainite to acicular ferrite after treatment with Ti, Mg and Ca. Ca addition decreased the strain field around inclusions and enhanced the ability of acicular ferrite nucleation. In situ observation of Ti–Mg–Ca steel showed that the movement of austenite grain boundaries was retarded and nucleation sites of acicular ferrite were greater than Ti–Ca steel because of Mg addition. Impact energy of HAZ at − 40 °C was increased from 7 to 232 J and showed excellent stability because of Ti–Mg–Ca treatment. High volume fraction of acicular ferrite acted as obstacles toward cleavage cracks.

Molecular dynamics simulations were employed to investigate the interaction between Fe(III) and an iron-binding site composed of THR259, ASP252, and GLU261 on the Fc domain of an IgG1. The goal was to provide microscopic mechanistic information for the photochemical, iron-dependent site-specific oxidative fragmentation of IgG1 at THR259 reported in our previous paper. The distance between Fe(III) and residues of interest as well as the binding pocket size was examined for both protonated and deprotonated THR259. The Fe(III) binding free energy (ΔG) was estimated by using an umbrella sampling approach. The pKashift of the THR259 hydroxyl group caused by the presence of nearby Fe(III) was estimated based on a thermodynamic cycle. The simulation results show that Fe(III) resides inside the proposed binding pocket and profoundly changes the pocket configuration. The ΔGvalues indicate that the pocket possesses a strong binding affinity for Fe(III). Furthermore, Fe(III) profoundly lowers the pKavalue of the THR259 hydroxyl group by 5.4 pKaunits.

Ozone-assisted combustion is an advanced combustion technology that is considered a promising means for the active control of combustion. Ozone addition can enhance combustion processes and extend the experimental parameters to extreme conditions. In this work, ozone-assisted low temperature oxidation of methanol and ethanol in a jet-stirred reactor (JSR) was carried out at atmospheric pressure, with a fuel initial mole fraction of 0.005, an equivalence ratio of 0.28, and in the temperature range of 330–800 K. Significant conversions of methanol and ethanol were observed in the low temperature region when ozone was added. Numerous intermediate species were analyzed and quantified by synchrotron vacuum ultraviolet photoionization mass spectrometry and gas chromatography, which are crucially important for unraveling the low temperature oxidation reaction network. The kinetic model of NUIGMech1.1 is tentatively updated to better explain the measured results, although the improvements of the C1–C2core mechanisms are difficult. Ozone addition enhances the action of the reaction channel of related radicals. Model analysis shows that the kinetics of Ö/ȮH/HȮ2atoms/radicals are crucial for the overall reaction progress, as well as the reaction of HȮ2radicals with ozone, which mainly contributes to the formation of ȮH radicals during the initial reaction stage. Inconsistency between measurements and model predictions highlights the considerable uncertainty in the C1-C2alcohols subchemistry at lower temperatures. The experimental results obtained in this work and model development will motivate further study of the low temperature oxidation chemistry of methanol and ethanol.

Background: The daily cycling of plant physiological processes is speculated to arise from the coordinated rhythms of gene expression. However, the dynamics of diurnal 3D genome architecture and their potential functions underlying the rhythmic gene expression remain unclear. Results: Here, we reveal the genome-wide rhythmic occupancy of RNA polymerase II (RNAPII), which precedes mRNA accumulation by approximately 2 h. Rhythmic RNAPII binding dynamically correlates with RNAPII-mediated chromatin architecture remodeling at the genomic level of chromatin interactions, spatial clusters, and chromatin connectivity maps, which are associated with the circadian rhythm of gene expression. Rhythmically expressed genes within the same peak phases of expression are preferentially tethered by RNAPII for coordinated transcription. RNAPII-associated chromatin spatial clusters (CSCs) show high plasticity during the circadian cycle, and rhythmically expressed genes in the morning phase and non-rhythmically expressed genes in the evening phase tend to be enriched in RNAPII-associated CSCs to orchestrate expression. Core circadian clock genes are associated with RNAPII-mediated highly connected chromatin connectivity networks in the morning in contrast to the scattered, sporadic spatial chromatin connectivity in the evening; this indicates that they are transcribed within physical proximity to each other during the AM circadian window and are located in discrete “transcriptional factory” foci in the evening, linking chromatin architecture to coordinated transcription outputs. Conclusion: Our findings uncover fundamental diurnal genome folding principles in plants and reveal a distinct higher-order chromosome organization that is crucial for coordinating diurnal dynamics of transcriptional regulation.

A reliable in vitro system can support and guide the development of subcutaneous (SC) drug products. Although several in vitro systems have been developed, they have some limitations, which may hinder them from getting more engaged in SC drug product development. This study sought to develop a novel in vitro system, namely, Emulator of SubCutaneous Absorption and Release (ESCAR), to better emulate the in vivo SC environment and predict the fate of drugs in SC delivery. ESCAR was designed using computer-aided design (CAD) software and fabricated using the three-dimensional (3D) printing technique. ESCAR has a design of two acceptor chambers representing the blood uptake pathway and the lymphatic uptake pathway, respectively, although only the blood uptake pathway was investigated for small molecules in this study. Via conducting a DoE factor screening study using acetaminophen solution, the relationship of the output (drug release from the “SC” chamber to the “blood circulation” chamber) and the input parameters could be modeled using a variety of methods, including polynomial equations, machine learning methods, and Monte Carlo simulation-based methods. The results suggested that the hyaluronic acid (HA) concentration was a critical parameter, whereas the influence of the injection volume and injection position was not substantial. An in vitro–in vivo correlation (IVIVC) study was developed using griseofulvin suspension to explore the feasibility of applying ESCAR in formulation development and bioequivalence studies. The developed LEVEL A IVIVC model demonstrated that the in vivo PK profile could be correlated with the in vitro release profile. Therefore, using this model, for new formulations, only in vitro studies need to be conducted in ESCAR, and in vivo studies might be waived. In conclusion, ESCAR had important implications for research and development and quality control of SC drug products. Future work would be focused on further optimizing ESCAR and expanding its applications via assessing more types of molecules and formulations.

n this paper, a generalized conforming thick/thin plate element based on the quadrilateral area coordinate system called AATF-PQ4 is developed. Based on the governing equations of Mindlin-Reissner plate theory, the fundamental analytical solutions are first derived, then using this trial functions to formulate element AATF-PQ4. In the case of thin plate, this thick/thin plate element is degraded into corresponding thin plate element automatically and is free from shear locking. Numerical examples show that the proposed element, AATF-PQ4, has a good precision for thick and thin plate.

Heat shock protein 70 (HSP70) is an important member of the heat shock protein family. It plays a key role in the process of protecting cells by facilitating the folding of nascent peptides as well as the cellular stress response. We isolated and sequenced a full-length HSP70 cDNA from planarian Dugesia japonica (designated Djhsp70) using rapid amplification of cDNA ends (RACE). Djhsp70 cDNA is highly homologous to other reported hsp70 family genes, and the deduced amino acid sequence shares several eukaryotic HSP70 family motifs. The length of the Djhsp70 ORF from planarian genomic DNA and cDNA was identical, which indicated the absence of introns in the Djhsp70 gene. Semi-quantitative RT-PCR was employed to detect the expression levels of Djhsp70 in response to stressors. Our results indicated that Djhsp70 was an inducible gene, expressed in response to temperature changes, amputation and starvation. Interestingly, the phylogenetic analysis of DjHSP70 supports the idea that planarians belong to a new phylogenetic position — Lophotrochozoans. This is the first molecular analysis of a heat shock protein gene in planarians.

Understanding the factors influencing users’ adoption and use of emerging information technologies is a critical issue for researchers and practitioners. This research aims to deepen our understanding of the underlying phenomena of technology adoption and use by examining whether there are gender differences in the importance of the perceived innovation characteristics on communication technologies use intentions. Specifically, we investigate whether gender moderates the influence of perceived relative advantage, compatibility, ease of use, visibility, result demonstrability and critical mass on intentions to use a communication technology: instant messaging. Results suggest a strong moderation effect of gender between perceptions of relative advantage, ease of use, visibility, result demonstrability, critical mass and use intentions. Contributions and future directions for research are presented.

Today’s business schools are looking for effective approaches to leverage technology to facilitate distributed learning and support collaborative group projects. Faculty need tools, methods, and best practices that can be adapted to support various learning models and learning objectives across academic disciplines. The application of groupware technology, Lotus Domino discussion databases, to support collaborative project-based learning is explored. From the instructor’s perspective, a variety of uses for discussion databases are described, including supporting course logistics, supporting student teams, and extending learning beyond the classroom. Recommendations for effective implementation include technical support issues, use of team databases, maintaining contact with remote students, and faculty time commitments.