19 resultados para cross-lagged panel method


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The synthesis of a novel heterocyclic–telechelic polymer, α,ω-oxetanyl-telechelic poly(3-nitratomethyl-3-methyl oxetane), is described. Infrared spectroscopy (IR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy have been used to confirm the successful synthesis, demonstrating the presence of the telechelic-oxetanyl moieties. Synthesis of the terminal functionalities has been achieved via displacement of nitrato groups, in a manner similar to that employed with other leaving groups such as azido, bromo, and nitro, initiated by nucleophiles. In the present case, displacement occurs on the ends of a nitrato-functionalized polymer driven by the formation of sodium nitrate, which is supported by the polar aprotic solvent N,N-dimethyl formamide. The formation of an alkoxide at the polymer chain ends is favored and allows internal back-biting to the nearest carbon bearing the nitrato group, intrinsically in an SN2(i) reaction, leading to α,ω-oxetanyl functionalization. The telechelic-oxetanyl moieties have the potential to be cross-linked by chemical (e.g., acidic) or radiative (e.g., ultraviolet) curing methods without the use of high temperatures, usually below 100°C. This type of material was designed for future use as a contraband simulant, whereby it would form the predominant constituent of elastomeric composites comprising rubbery polymer with small quantities of solids, typically crystals of contraband substances, such as explosives or narcotics. This method also provides an alternative approach to ring closure and synthesis of heterocycles.

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There are conflicting predictions in the literature about the relationship between FDI and entrepreneurship. This paper explores how foreign direct investment (FDI) inflows, measured by lagged cross-border mergers and acquisitions (M&A), affect entrepreneurial entry in the host economy. We have constructed a micro-panel of more than two thousand individuals in each of seventy countries, 2000–2009, linked to FDI by matching sectors. We find the relationship between FDI inflows and domestic entrepreneurship to be negative across all economies. This negative effect is much more pronounced in developed than developing economies and is also identified within industries, notably in manufacturing. Policies to encourage FDI via M&A need to consider how to counteract the prevailing adverse effect on domestic entrepreneurship.

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BACKGROUND: No studies to date have investigated cumulative anticholinergic exposure and its effects in adults with intellectual disabilities. AIMS: To determine the cumulative exposure to anticholinergics and the factors associated with high exposure. METHOD: A modified Anticholinergic Cognitive Burden (ACB) scale score was calculated for a representative cohort of 736 people over 40 years old with intellectual disabilities, and associations with demographic and clinical factors assessed. RESULTS: Age over 65 years was associated with higher exposure (ACB 1-4 odds ratio (OR) = 3.28, 95% CI 1.49-7.28, ACB 5+ OR = 3.08, 95% CI 1.20-7.63), as was a mental health condition (ACB 1-4 OR = 9.79, 95% CI 5.63-17.02, ACB 5+ OR = 23.74, 95% CI 12.29-45.83). Daytime drowsiness was associated with higher ACB (P<0.001) and chronic constipation reported more frequently (26.6% ACB 5+ v. 7.5% ACB 0, P<0.001). CONCLUSIONS: Older people with intellectual disabilities and with mental health conditions were exposed to high anticholinergic burden. This was associated with daytime dozing and constipation.

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This cross-country report shares first insights from the World's Largest Panel Study of Social Enterprises, which covers seven European Countries (Germany, Hungary, Portugal, Romania, Spain, Sweden, the United Kingdom), China and Russia. It captures the behavior and characteristics of representative samples of social enterprises in these countries who are employers. The report covers a range of topics from profiling social enterprise directors and their social enterprises, to innovation activities and barriers, their entrepreneurial orientation, social missions, social impact metrics to summarizing policy recommendations that social entrepreneurs would like to see being implemented in their countries. Who should read this report? The report is written for social enterprises, social enterprises support organisations and policy makers who want to get an overview of social enterprise in the UK. Thank you to all the social entrepreneurs who made this report possible by participating in our study!