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Given the growing trend of using digital platforms for exporters' internationalization, the management of exporters' online internationalization has become a critical issue. However, academic research in this area remains sparse. Specifically, little is known about when and under what conditions exporters may consider discontinuing the use of a digital platform for exporting, i.e., online de-internationalization. This study develops and tests a theoretical framework for these determinants and the contingencies for exporters' online de-internationalization. Specifically, drawing on the de-internationalization literature, we identify sets of internal and external antecedents of exporters' intention to discontinue the use of digital platforms for exporting. Furthermore, we examine the moderating effect of technological opportunism. Based on a unique sample of Chinese exporters registered on Alibaba.com, the world's largest business-to-business platform, the empirical findings support our proposed determinants of online de-internalization. This article ultimately discusses the theoretical and managerial implications.
Persistent cognitive deficits and functional impairments are associated with bipolar disorder (BD), even during the euthymic phase. The dysfunction of default mode network (DMN) is critical for self-referential and emotional mental processes and is implicated in BD. The current study aims to explore the balance of excitatory and inhibitory neurotransmitters, i.e. glutamate and γ-aminobutyric acid (GABA), in hubs of the DMN during the euthymic patients with BD (euBD).
Method
Thirty-four euBD and 55 healthy controls (HC) were recruited to the study. Using proton magnetic resonance spectroscopy (1H-MRS), glutamate (with PRESS sequence) and GABA levels (with MEGAPRESS sequence) were measured in the medial prefrontal cortex/anterior cingulate cortex (mPFC/ACC) and the posterior cingulate gyrus (PCC). Measured concentrations of excitatory glutamate/glutamine (Glx) and inhibitory GABA were used to calculate the excitatory/inhibitory (E/I) ratio. Executive and attentional functions were respectively assessed using the Wisconsin card-sorting test and continuous performance test.
Results
euBD performed worse on attentional function than controls (p = 0.001). Compared to controls, euBD had higher E/I ratios in the PCC (p = 0.023), mainly driven by a higher Glx level in the PCC of euBD (p = 0.002). Only in the BD group, a marginally significant negative association between the mPFC E/I ratio (Glx/GABA) and executive function was observed (p = 0.068).
Conclusions
Disturbed E/I balance, particularly elevated Glx/GABA ratio in PCC is observed in euBD. The E/I balance in hubs of DMN may serve as potential biomarkers for euBD, which may also contribute to their poorer executive function.
Unmanned aerial vehicles (UAVs) have recently been widely applied in a comprehensive realm. By enhancing computer photography and artificial intelligence, UAVs can automatically discriminate against environmental objectives and detect events that occur in the real scene. The application of collaborative UAVs will offer diverse interpretations which support a multiperspective view of the scene. Due to the diverse interpretations of UAVs usually deviating, UAVs require a consensus interpretation for the scenario. This study presents an original consensus-based method to pilot multi-UAV systems for achieving consensus on their observation as well as constructing a group situation-based depiction of the scenario. Taylor series are used to describe the fuzzy nonlinear plant and derive the stability analysis using polynomial functions, which have the representations $V(x )={m_{\textrm{1} \le l \le N}}({{V_\textrm{l}}(x )} )$ and ${V_l}(x )={x^T}{P_l}(x )x$. Due to the fact that the ${\dot{P}_l}(x )$ in ${\dot{V}_l}(x )={\dot{x}^T}{P_l}(x )x + {x^T}{\dot{P}_l}(x )x + {x^T}{P_l}(x )\dot{x}$ will yield intricate terms to ensure a stability criterion, we aim to avoid these kinds of issues by proposing a polynomial homogeneous framework and using Euler's functions for homogeneous systems. First, this method permits each UAV to establish high-level conditions from the probed events via a fuzzy-based aggregation event. The evaluated consensus indicates how suitable is the scenario collective interpretation for every UAV perspective.
The Tuluanshan Formation of the eastern Coastal Range of Taiwan overlies an andesitic core complex presumed to be the source of hydrothermal fluids responsible for the Si- and Mg-rich mineralization of sepiolite and palygorskite (attapulgite) which are found in veins within fissures and in fracture zones of the volcanic rocks of the region. This study was undertaken in order to understand these relationships better by characterizing sepiolite and palygorskite in this Formation and by examining their occurrence and distribution in the Tungho (TH) and Chunjih (CJ) areas. Samples were analyzed using X-ray diffraction (XRD), thermal analysis, Fourier-transform infrared (FTIR) spectroscopy, and petrographic, scanning (SEM), and transmission (TEM) electron microscopic methods. Sepiolite and palygorskite are blocky and earthy-type materials that display fibrous characteristics when viewed using TEM and SEM and occurred alone or with chalcedony in veins. The fibers of blocky sepiolite are commonly intercalated with smectite but the earthy type of sepiolite and palygorskite observed in this study displayed precipitation from fluid enriched in Si, Al, Mg, and minor Fe and depleted in other ions at an earlier stage of offset of the andesitic veins. Continuation of reverse faulting and high shearing stress caused the precipitation of a significant quantity of interlaminated sepiolite. Sepiolite and palygorskite were formed at an earlier stage of fluid interaction relative to smectite in the Tuluanshan Formation.
National health insurance (NHI) Taiwan has provided additional markups on dental service fees for people with specific disabilities, and the expenditure has increased significantly from TWD473 million (USD15 million) in 2016 to TWD722 million (USD24 million) in 2022. The purpose of this study was to determine oral health risk and to develop a risk assessment model for capitation outpatient dental payments in children with Autism.
Methods
Based on the literature and expert opinion, we developed a level of oral health risk model from the claim records of 2019. The model uses oral outpatient claim data to analyze: (i) the degree of caries disease; (ii) the level of dental fear or cooperation; and (iii) the level of tooth structure. Each factor was given a score from zero to four and a total score was calculated. Low-, medium-, and high-risk groups were formed based on the total points. The oral health risk capitation models are estimated by ordinary least squares using an individual’s annual outpatient dental expenditure in 2019 as the dependent variable. For subgroups based on age group and level of disability, expenditures predicted by the models are compared with actual outpatient dental expenditures. Predictive R-squared and predictive ratios were used to evaluate the model’s predictability.
Results
The demographic variables, level of oral health risk, preventive dental care, and the type of dental health care predicted 30 percent of subsequent outpatient dental expenditure in children with autism. For subgroups (age group and disability level) of high-risk patients, the model substantially overpredicted the expenditure, whereas underprediction occurred in the low-risk group.
Conclusions
The risk-adjusted model based on principal oral health was more accurate in predicting an individual’s future expenditure than the relevant study in Taiwan. The finding provides insight into the important risk factor in the outpatient dental expenditure of children with autism and the fund planning of dental services for people with specific disabilities.
Evidence on the long-term comparative effectiveness of posttraumatic stress disorder (PTSD) psychotherapies in adults remains unknown. Therefore, we performed an extensive network meta-analysis of randomised controlled trials (RCTs) to determine the comparative effectiveness of psychotherapies for people diagnosed with PTSD.
Methods
A comprehensive search was conducted in Cochrane library, Embase, Medline-OVID, PubMed, Scopus, and Psych-Info until March 2021. Studies on the effectiveness of cognitive processing therapy (CPT), cognitive therapy (CT), eye movement desensitisation reprocessing (EMDR), narrative exposure therapy (NET), prolonged exposure (PE), cognitive behavioural therapy (CBT), present-centred therapy (PCT), brief eclectic psychotherapies (BEP), psychodynamic therapy (PDT) or combination therapies compared to no treatment (NT) or treatment as usual (TAU) in adults with PTSD were included. Frequentist and Bayesian approaches were used for analysis in R-software.
Results
We included 98 RCTs with 5567 participants from 18 897 studies. CPT, EMDR, CT, NET, PE, CBT, and PCT were significant to reduce PTSD symptoms (SMD range: −1.53 to −0.75; Certainty: very low to high) at immediate post-treatment and ranked accordingly. Longitudinal analysis found EMDR (1.02) and CPT (0.85) as the significant therapies with large effect size in short-term and long-term follow-up, respectively. NET and CPT showed higher proportion of loss of PTSD diagnosis (RR range: 5.51–3.45) while there were no significant psychotherapies for retention rate compared to NT.
Conclusions:
Our findings provide evidence for improving current guidelines and informing clinical decision-making for PTSD management. However, the best PTSD treatment plan should be tailored to patients' needs, characteristics, and clinician expertise.
Foundations of Gas Dynamics covers supersonic and subsonic flow phenomena where compressibility of the fluid cannot be ignored. It finds application in jet and rocket propulsion systems as well as handling industrial gas flow at high speeds. Students and engineers in the mechanical, aerospace, and chemical disciplines will find it useful. It begins with basic concepts such as isentropic flows, shock, and supersonic expansion waves in one dimension. These are followed by one-dimensional flows with friction and heat exchange. Two-dimensional theory with small perturbations is presented, with its applications illustrated by supersonic airfoils. Method of characteristics is used for flows with two independent variables, either with two spatial coordinates or with time variations in one dimension. In later chapters, acoustic wave propagation, supersonic flow combustion, and unsteady shock formation are treated thoroughly. The book ends with a chapter on basic hypersonic flow, with a discussion of similarity rules.