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关键词： industrial ecology   material efficiency   material flow analysis (MFA)   modeling   steel   systems modeling  

摘要： Increased recycling and reuse rates are a central part of the objectives laid out by the COP21. Nonetheless, the practical implementation of what has been called the circular economy, as well as its true potential, are not easily established. This is because the impact and implementation time scales of any intervention depend on knowing the lifetime of products, which is frequently unknown. This is particularly true in construction, responsible for 39% of worldwide emissions, 11% of which are embodied. Most material flow analysis (MFA) models will simply assume a range of plausible life expectancies when bottom-up data are lacking. In this work, we propose a novel method of identification using the high quality but highly aggregated trade data available and use it to establish a "mortality curve" for buildings and other long-lasting products. This identification method is intended to provide more reliable inputs to existing MFA models. It is widely applicable because of the general availability of the underlying data. Using it on United Kingdom trade data, we identify product classes at 1 year for packaging/home scrap, 1 to around 10 years for vehicles/equipment, and around 50 years for construction. The identification approach was then validated by using classical approaches using bottom-up data for vehicles.

摘要： The article discusses the ways in which lexicalization of vertical motion takes place in two satellite-framed languages: Polish and Russian. In this typological category the manner of motion is typically rendered by the verb. The analysis of the descriptions of motion events by native speakers of these two genetically related languages shows that the lexicalization pattern of vertical motion differs from the horizontal one. First of all, when describing vertical relations, respondents less frequently code the manner of motion in the verb than when talking about motion along the horizontal plane. What is more, the results show that both Russian and Polish respondents use more motion verbs to describe vertical than horizontal relations, which points to the natural human tendency to code novel situations.

关键词： Technology   New products   Consumer research   Segmentation   Probit model  

摘要： Using the Technology Adoption Propensity (TAP) index, a psychometric scale that measures four dimensions of consumers' technological predispositions, we examine the relative influence of contributing (optimism and proficiency) and inhibiting (dependence and vulnerability) dispositional attitudes on the adoption of a varied range of 19 technologies. Our results indicate considerable differences in the relation between technology usage and the attitudes of respondents across the technologies. We show that individuals can be grouped into three technology clusters based on technological dispositions: high proficiency/low vulnerability;low proficiency & optimism/high vulnerability;high optimism/low vulnerability. Each cluster may indicate a need for a particular sales strategy given differences in consumer attitudes.

关键词： autoimmune diseases   arthritis   health services research  

摘要： Correspondence to Dr Sarah Stewart, Medicine, The University of Auckland, Auckland 1023, New Zealand; ***@*** Article placement order within journal issues has the potential to influence perceived research importance, with earlier listed articles being more visible and more likely to be downloaded and cited.1 2 In an analysis of serial rheumatology journals published between 2013 and 2018, we reported that certain rheumatic diseases were prioritised within journal issues.1 Articles about rheumatoid arthritis were preferentially ordered at the front of issues, while other diseases including connective tissue diseases, crystal arthritis, paediatric syndromes and pain syndromes were consistently ordered towards the back. Each article was coded into one of six disease categories: connective tissue disorders, crystal arthritis, osteoarthritis, rheumatoid arthritis, spondyloarthropathies and other rheumatic diseases with small numbers of articles (online supplemental table 1). Comparisons between issues with and without content grouped by disease demonstrated a significant difference in SAPI distributions; from January 2019, articles about rheumatoid arthritis were placed more towards the front of issues (p=0.004), and articles about connective tissue diseases, crystal arthritis, osteoarthritis and other diseases were placed towards the back of issues (all p<0.034) (figure 1).

关键词： Homotopy category   Compactly generated triangulated category   Cotorsion pair   Cover and envelope   Cotorsion flat resolution  

摘要： This paper aims at studying the homotopy category of cotorsion flat left modules K(CotF- R) over a ring R. We prove that if R is right coherent, then the homotopy categoryK(dg-CotF- R) of dg-cotorsion complexes of flat R-modules is compactly generated. This uses firstly the existence of cotorsion flat preenvelopes over such rings and, secondly, the existence of a complete cotorsion pair (Kp(Flat- R), K(dg-CotF- R)) in the homotopy category K(Flat- R) of complexes of flat R-modules, for arbitrary R. In the setting of quasi coherent sheaves over a Noetherian scheme, this cotorsion pair was discovered in the literature. However, we use a more elementary argument that gives this cotorsion pair for arbitrary R. Next we deal with cotorsion flat resolutions of complexes and define and study the notion of cotorsion flat dimension for complexes of flat R-modules. We also obtain an equivalence K(dg-CotF- R) approximate to K(Proj- R) of triangulated categories where K(Proj- R) is the homotopy category of projective R-modules. Combined with the aforementioned result, this recovers a result from Neeman, asserting the compact generation of K(Proj- R) over right coherent R. Also we get the unbounded derived category D( R) of R as a Verdier quotient of K(dg-CotF- R).

关键词： Occupation   Grip strength   Sociodemographic factors   Health-related factors  

摘要： Purpose This study explored the association between occupational categories and muscle strength using handgrip strength (HGS) while considering sociodemographic and health-related factors in Korean men using a national survey. Methods Using cross-sectional data of 8380 men (59.9 +/- 16.6 years of age), the occupational categories held the longest duration and HGS levels (normal vs. weak) were determined. Logistic regression was applied with adjustment for sociodemographic factors, work-related factors (working hours and schedule), and health-related factors (physical activity, sedentary time, resistance exercise, alcohol consumption, smoking status, chronic illness, subjective health status, weight category, metabolic syndrome, and protein intake). Results Weak HGS prevalence was lowest in male managerial or professional workers (1.5%) and highest in male skilled agricultural, forestry, fishery, or craft and the related trades workers (16.4%). Compared to male managerial or professional workers, the odds for weak HGS increased in male service/sales workers (OR 2.41;95% CI 1.45-3.99) and male manual workers [agricultural/forestry/fishery/craft and related trades workers, OR 2.94 (95% CI 1.78-4.83);equipment/machine operating/assembling workers, OR 1.68 (95% CI 1.05-2.71);and elementary workers, OR 3.43 (95% CI 1.95-6.05)] in the fully adjusted model. Regardless of age groups, income, working hours, strength exercise, and sedentary time levels, and chronic illness and metabolic syndrome status, male manual workers were more likely to have weak HGS compared to male non-manual workers. Conclusion Male manual workers may have a higher risk for weak muscle strength compared to male non-manual workers regardless of sociodemographic, work-related, and health-related factors.

关键词： V-category   V-group   Protomodular object   Metric and ultrametric group  

摘要： We consider compatible group structures on a V-category, where V is a quantale, and we study the topological and algebraic properties of such groups. Examples of such structures are preordered groups, metric and ultrametric groups, probabilistic (ultra)metric groups. In particular, we show that, when V is a frame, symmetric V-groups satisfy very strong categorical-algebraic properties, typical of the category of groups. In particular, symmetric V-groups form a protomodular category. (C) 2020 Elsevier B.V. All rights reserved.

关键词： COVID-19   Cluster   Pandemic   Viral infection  

摘要： Background: As a result of the high contagiousness and transmissibility of SARS-CoV-2, studying the location of the case clusters that will follow, will help understand the risk factors related to the disease transmission. In this study, we aim to identify the transmission cluster category and settings that can guide decision-makers which areas to be opened again. Methods: A thorough review of the literature and the media articles were performed. After data verification, we included cluster data from eight countries as of 16th May 2020. Clusters were further categorized into 10 categories and analysis was performed. The data was organized and presented in an easily accessible online sheet. Results: Among the eight included countries, we have found 3905 clusters and a total number of 1,907,944 patients. Indoor settings (mass accommodation and residential facilities) comprised the highest number of both number of clusters (3315/3905) and infected patients (1,837,019/1,907,944), while the outdoor ones comprised 590 clusters and 70,925 patients. Mass accommodation was associated with the highest number of cases in 5 of the 7 countries with data available. Social events and residential settings were responsible for the highest number of cases in the two remaining countries. In the USA, workplace facilities have reported 165 clusters of infection including 122 food production facilities. Conclusions: Lockdown could truly be a huge burden on a country's economy. However, with the proper knowledge concerning the transmissibility and the behaviour of the disease, better decisions could be made to guide the appropriate removal of lockdown across the different fields and regions. (c) 2021 Published by Elsevier Ltd on behalf of King Saud Bin Abdulaziz University for Health Sciences. This is an open access article under the CC BY-NC-ND license (http://***/licenses/bync-nd/4.0/).

关键词： 03B38   18C50   03G30  

摘要： We define and develop the infrastructure of homotopical inverse diagrams in categories with attributes. Specifically, given a category with attributes C and an ordered homotopical inverse category I, we construct the category with attributes C-I of homotopical diagrams of shape I in C and Reedy types over these;and we show how various logical structure (II-types, identity types, and so on) lifts from C to C-I. This may be seen as providing a general class of diagram models of type theory. In a companion paper "The homotopy theory of type theories" (Kapulkin, Lumsdaine, Advances in Mathematics, 2018), we apply the present results to construct semi-model structures on categories of contextual categories. (C) 2020 Elsevier B.V. All rights reserved.