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Thermophoretic collection of virus-laden (SARS-CoV-2) aerosols
Detecting the existence of SARS-CoV-2 in the indoor atmosphere is a practical solution to track the prevalence and prevent the spread of the virus. In this work, a thermophoretic approach is presented to collect the novel coronavirus-laden aerosols from the air and accumulate to high concentrations adequate for the sensitivity of viral RNA detection. Among the factors, the density and particle size have negligible effects on particle trajectory, while the vertical coordinates of particles increase with the rise in heating source temperature. When the heating temperature is higher than 355 K, all of the particles exit the channel from one outlet; thus, the collecting and accumulating of virus-laden aerosols can be realized. This study provides a potential approach to accelerate the detection of SARS-CoV-2 and avoid a false negative in the following RNA test. © 2021 Author(s)
Impact of stoichiometry and strain on Ge1−x Sn x alloys from first principles calculations
We calculate the electronic structure of germanium-tin (Ge1-x Sn x ) binary alloys for 0 ≤ x ≤ 1 using density functional theory (DFT). Relaxed alloys with semiconducting or semimetallic behaviour as a function of Sn composition x are identified, and the impact of epitaxial strain is investigated by constraining supercell lattice constants perpendicular to the [001] growth direction to the lattice constants of Ge, zinc telluride, or cadmium telluride substrates. It is found that application of 1% tensile strain reduces the Sn composition required to bring the (positive) direct band gap to zero by approximately 5% compared to a relaxed Ge1-x Sn x alloy having the same gap at Γ. On the other hand, compressive strain has comparatively less impact on the alloy band gap at Γ. Using DFT calculated alloy lattice and elastic constants, the critical thickness for Ge1-x Sn x thin films as a function of x and substrate lattice constant is estimated, and validated against supercell DFT calculations and experiment. The analysis correctly predicts the Sn composition range at which it becomes energetically favourable for Ge1-x Sn x /Ge to become amorphous. The influence of stoichiometry and strain is examined in relation to reducing the magnitude of the inverted ('negative') Γ7-Γ8+ band gap, which is characteristic of semimetallic alloy electronic structure. Based on our findings, strategies for engineering the semimetal-to-semiconductor transition via strain and quantum confinement in Ge1-x Sn x nanostructures are proposed. © 2021 IOP Publishing Ltd
Understanding and addressing the treatment gap in mental healthcare: economic perspectives and evidence from China
A common challenge faced by the healthcare systems in many low- and middle-income countries is the substantial unmet mental healthcare needs, or the large gap between the need for and the provision of mental healthcare treatment. This paper investigates the potential causes of this treatment gap from the perspective of economics. Specifically, we hypothesize that people with mental illness face 4 major hurdles in obtaining appropriate healthcare, namely the high nonmonetary cost due to stigma, the high out-of-pocket payment due to insufficient public funds devoted to mental health, the high time costs due to low mental healthcare resource availability, and the low treatment benefit due to slow technology diffusion. We use China as a study setting to show country-specific evidence. Our analysis supports the above theoretical argument on the 4 barriers to access, which in turn sheds light on the effective approaches to mitigate the treatment gap. Four policy options are then discussed, including an information campaign for mental health awareness, increasing public investment in primary mental healthcare resources, transforming the healthcare system towards an integrated people-centered system and capitalizing on e-health technologies
Beyond the scope of the deal: configuration of technology alliance portfolios and the introduction of management innovation
While firms invest in portfolios of technology alliances primarily seeking technological benefits (e.g. access to novel technological knowledge to develop product innovations), an adequate portfolio of technology alliances can also bring non-technological benefits, such as access to novel managerial knowledge, which can result in management innovation. However, it remains unclear under what conditions technology alliance portfolios yield such benefits. Drawing from the literature on knowledge utilization from alliance portfolios, we examine how the configuration of a firm’s technology alliance portfolio affects the likelihood of the firm introducing management innovation. Our panel data analyses of Spanish manufacturing firms for 2008–2016 reveal that a firm is more likely to introduce management innovation when its alliance portfolio shows diversity of partner types; however, this positive effect of diversity becomes less pronounced as the alliance portfolio becomes more oriented towards exploration (i.e. relatively greater presence of research focused partner types). Our study also provides recommendations for managers seeking to connect the technological and non-technological spheres of innovation: a technological alliance portfolio that brings together diverse partner types while avoiding excessive presence of research-focused partner types may offer greater opportunity for management innovation
Income-related health inequality among Chinese adults during the COVID-19 pandemic: evidence based on an online survey
Background: Partial- or full-lockdowns, among other interventions during the COVID-19 pandemic, may disproportionally affect people (their behaviors and health outcomes) with lower socioeconomic status (SES). This study examines income-related health inequalities and their main contributors in China during the pandemic.
Methods: The 2020 China COVID-19 Survey is an anonymous 74-item survey administered via social media in China. A national sample of 10,545 adults in all 31 provinces, municipalities, and autonomous regions in mainland China provided comprehensive data on sociodemographic characteristics, awareness and attitudes towards COVID19, lifestyle factors, and health outcomes during the lockdown. Of them, 8448 subjects provided data for this analysis. Concentration Index (CI) and Corrected CI (CCI) were used to measure income-related inequalities in mental health and self-reported health (SRH), respectively. Wagstaff-type decomposition analysis was used to identify contributors to health inequalities.
Results: Most participants reported their health status as “very good” (39.0%) or “excellent” (42.3%). CCI of SRH and mental health were − 0.09 (p < 0.01) and 0.04 (p < 0.01), respectively, indicating pro-poor inequality in ill SRH and pro-rich inequality in ill mental health. Income was the leading contributor to inequalities in SRH and mental health, accounting for 62.7% (p < 0.01) and 39.0% (p < 0.05) of income-related inequalities, respectively. The COVID-19 related variables, including self-reported family-member COVID-19 infection, job loss, experiences of food and medication shortage, engagement in physical activity, and five different-level pandemic regions of residence, explained substantial inequalities in ill SRH and ill mental health, accounting for 29.7% (p < 0.01) and 20.6% (p < 0.01), respectively. Self-reported family member COVID-19 infection, experiencing food and medication shortage, and engagement in physical activity explain 9.4% (p < 0.01), 2.6% (the summed contributions of experiencing food shortage (0.9%) and medication shortage (1.7%), p < 0.01), and 17.6% (p < 0.01) inequality in SRH, respectively (8.9% (p < 0.01), 24.1% (p < 0.01), and 15.1% (p < 0.01) for mental health).Conclusions: Per capita household income last year, experiences of food and medication shortage, self-reported family member COVID-19 infection, and physical activity are important contributors to health inequalities, especially mental health in China during the COVID-19 pandemic. Intervention programs should be implemented to support vulnerable groups
Methodology in EAP: still an overlooked issue?
In 2003 it was suggested that insufficient attention had been paid to methodology and pedagogy in EAP and that there had been an over-emphasis on the ‘what’ at the possible expense of the ‘how’. While conferences and other professional events have gone some way towards addressing this issue, in terms of EAP journal outputs, as a survey of the Journal of English for Academic Purposes (JEAP) shows, not very much seems to have changed. The pages of JEAP still suggest a dearth of research interest in issues related to EAP methodology. This reflective paper argues that much greater prominence needs to be given to pedagogical matters in EAP, not least because teaching still accounts for the bulk of what most EAP practitioners do. The paper further suggests that the transfer of methodology and pedagogy from General ELT to EAP should be considered more critically than has hitherto been the case
Establishing systems & processes for classroom observation of teaching in EAP
Classroom observation can boast a long and venerable history in English Language Teaching and is now an accepted feature of professional life. Such observation is either seen as being evaluative in nature, in which case it is typically linked with appraisal systems and carried out by a line manager, or it may be viewed more developmentally, in which case it is more commonly conducted on a peer-to-peer basis. While the mechanisms for both types of classroom observation in General ELT contexts are now quite well established, the same cannot always be said of observations in EAP, where approaches may be more idiosyncratic and based on the preferences of individual institutions. In the specific case of evaluative classroom observation, a further consideration is whether the observation should be focussing on the same kinds of features as those found in General ELT contexts or looking for evidence of something else. This reflective paper charts the evolution, establishment and delivery of one such EAP-specific approach to evaluative classroom observation, which was conducted at the University of Nottingham Ningbo China (UNNC) between 2009 and 2015
Iterative group-based and difference ranking method for online rating systems with spamming attacks
It is significant to assign reputation scores to users and identify spammers in the bipartite rating networks. In this paper, we propose an Iterative Group-based and Difference Ranking (IGDR) method, which is based on the original Iterative Group-based Ranking (IGR) method. The IGR method considers users grouping behaviors, but it ignores the characteristics of the individual ratings. It is discovered that individual rating characteristics could also contribute to the redistribution of reputation scores of users. The user with a smaller rating deviation will be given a higher reputation score. The proposed method outperforms IGR method ranging from 8% to 163% tested on three real datasets. It also can be applied to deal with big data in a short time
A decision support system for urban infrastructure inter-asset management employing domain ontologies and qualitative uncertainty-based reasoning
Urban infrastructure assets (e.g. roads, water pipes) perform critical functions to the health and well-being of society. Although it has been widely recognised that different infrastructure assets are highly interconnected, infrastructure management in practice such as planning, installation and maintenance are often undertaken by different stakeholders without considering these dependencies due to the lack of relevant data and cross-domain knowledge, which may cause unexpected cascading social, economic and environmental effects. In this paper, we present a knowledge based decision support system for urban infrastructure inter-asset management. By considering various infrastructure assets (e.g. road, ground, cable), triggers (e.g. pipe leaking) and potential consequences (e.g. tra c disruption) as a holistic system, we model each sub-domain using a modular ontology and encapsulate the interdependence between them using a set of rules. Moreover, qualitative likelihood is assigned to each rule by domain experts (e.g. civil engineers) to encode the uncertainty of knowledge, and an inference engine is applied to predict the potential consequences of a given trigger with location specific data and the encoded rules. A web-based prototype system has been developed based on the above concept and demonstrated to a wide range of stakeholders. The system can assist in the process of decision making by aiding data collation and integration, as well as presenting potential consequences of possible triggers, advising on whether additional information is needed or suggesting ways of obtaining such information. The work shows an intelligent approach to integrate and process multi-source data to pioneer a novel way to aid a complex decision process with a high social impact
The role of provincial government spending composition in growth and convergence in China
China’s development policy since 1978 has differed across regions. With rapid aggregate growth has come widening regional inequality. The fiscal decentralisation reforms in 1994 shifted political pressure onto provincial officials to boost local growth through local public investments. These investments affect regional convergence by counteracting regulatory frictions in factor accumulation, and can also determine steady-state growth. However, the effect of public spending allocations across physical and human capital on growth and convergence processes is empirically unexplored for Chinese provinces. We take provincial time-series data on public spending by category, finding local public spending and its components augment convergence rates differently across regions. Spending on education and health contributes significantly more to growth and convergence than capital spending, confirming that the public capital-spending bias is not a local growth-optimising strategy. We suggest a policy of aligning local government promotion incentives to human capital targets to correct local resource misallocation