392 research outputs found
The Leninist State under Threat? The Politics of Economic Reform in China
Summary Summary This article examines the political origins, content and impact of China's post?Mao economic reforms and argues that while they may well lead towards a more ‘pluralistic’ political process along corporatist ‘lines’, we cannot assume that they will lead automatically to more wide?ranging political democratisation. Resumen Resumen ¿El estado leninista bajo amenaza? La política de las reformas económicas en China Este artículo examina los orígenes políticos, el contenido y el impacto de las reformas económicas posteriores a Mao y sostiene que aun cuando ellas bien pueden derivar en un proceso político más ‘pluralista’ junto a ‘líneas’ corporatistas, no se puede suponer que conducirán automáticamente a una democratización de más vasto alcance
Optically induced forces and torques:Interactions between nanoparticles in a laser beam
Distinctive optical forces and torques arise between nanoparticles irradiated by intense laser radiation. These forces, associated with a pairwise process of stimulated scattering, prove to enable the possibility of producing significant modifications to both the form and magnitude of interparticle forces, with additional contributions arising in the case of dipolar materials. Moreover, such forces have the capacity to generate unusual patterns of nanoscale response, entirely controlled by the input beam characteristics- principally the optical frequency, intensity, and polarization. Based on quantum electrodynamical theory, a general result is secured for the laser-induced force under arbitrary conditions, incorporating both static and dynamic coupling mechanisms. Specific features of the results are identified for pairs of particles with prolate cylindrical symmetry, e.g., carbon nanotubes, where it is shown that the laser-induced forces and torques are sensitive functions of the pair spacing and orientation, and the laser beam geometry; significantly, they can be either repulsive or attractive according to conditions. For nanoparticles trapped in a Laguerre-Gaussian laser beam the results also reveal additional and highly distinctive torques that suggest further possibilities for nanomanipulation with light. The paper concludes with a discussion on several potential applications of such forces. © 2005 The American Physical Society
Crystal Structure of Orthorhombic {bis-[(pyridin-2-yl)methyl](3,5,5,5-tetrachloropentyl)amine-κ\u3csup\u3e3\u3c/sup\u3e\u3cem\u3eN,N\u27,N\u27\u27\u3c/em\u3e}chloridocopper(II) Perchlorate
In the title compound, [CuCl(C17H19Cl4N3)]ClO4, the CuII ion adopts a distorted square-planar geometry defined by one chloride ligand and the three nitrogen atoms from the bis[(pyridin-2-yl)methyl](3,5,5,5-tetrachloropentyl)amine ligand. The perchlorate counter-ion is disordered over three sets of sites with refined occupancies 0.0634 (17), 0.221 (16) and 0.145 (7). In addition, the hetero-scorpionate arm of the bis[(pyridin-2-yl)methyl](3,5,5,5-tetrachloropentyl)amine ligand is disordered over two sets of sites with refined occupancies 0.839 (2) and 0.161 (2). In the crystal, weak Cu⋯Cl interactions between symmetry-related molecules create a dimerization with a chloride occupying the apical position of the square-pyramidal geometry typical of many copper(II) chloride hetero-scorpionate complexes
Cycling and disability: A call for further research
© 2017 Cycling can offer health benefits, and these benefits are relevant for disabled people. Few disabled people cycle, and disability is under-researched in cycling studies. This paper (i) reviews current research into disabled cycling, and provides a critique of inclusive cycle design guidance; and (ii) reports on a recent study which highlights some of the significant issues faced by disabled cyclists in accessing cycle infrastructure and using designated cycle networks. A semi-structured focus group was conducted with eight inclusive cycle scheme users, seven care providers supporting the majority of the cyclists, and the scheme organiser. We conclude that the needs of disabled cyclists are increasingly being taken into consideration in infrastructure design guidance, but there are many issues to be resolved before cycling is accessible to and usable by disabled people. There is little research on understanding the experiences of disabled cyclists, and hence there is a knowledge gap concerning the efficacy of current design guidance. The data presented in this paper provide a useful first insight into the experiences of a group of disabled cyclists, but these data are limited to the specific context of that group. Further research is needed
Male circumcision and penile cancer: a systematic review and meta-analysis
OBJECTIVE: We systematically reviewed the evidence of an association between male circumcision and penile cancer. METHODS: Databases were searched using keywords and text terms for the epidemiology of penile cancer. Random effects meta-analyses were used to calculate summary odds ratios (ORs) and 95% confidence intervals (CI). RESULTS: We identified eight papers which evaluated the association of circumcision with penile cancer, of which seven were case-control studies. There was a strong protective effect of childhood/adolescent circumcision on invasive penile cancer (OR = 0.33; 95% CI 0.13-0.83; 3 studies). In two studies, the protective effect of childhood/adolescent circumcision on invasive cancer no longer persisted when analyses were restricted to boys with no history of phimosis. In contrast, there was some evidence that circumcision in adulthood was associated with an increased risk of invasive penile cancer (summary OR = 2.71; 95% CI 0.93-7.94; 3 studies). There was little evidence for an association of penile intra-epithelial neoplasia and in situ penile cancer with circumcision performed at any age. CONCLUSIONS: Men circumcised in childhood/adolescence are at substantially reduced risk of invasive penile cancer, and this effect could be mediated partly through an effect on phimosis. Expansion of circumcision services in sub-Saharan Africa as an HIV prevention strategy may additionally reduce penile cancer risk
The prognostic significance of micrometastases in node-negative squamous cell carcinoma of the vulva
Nodal involvement is one of the most significant prognostic factors in squamous cell carcinoma (SCC) of the vulva. We conducted a retrospective analysis of 31 women with histologically node-negative SCC from a population-based cohort of Grampian women. Median follow-up was 42 months after radical vulvectomy with groin node dissection. In total, 13 women (42%) were found to have micrometastases on immunohistochemistry. The risk of recurrence was almost 20-fold higher in those with micrometastases compared to those without (hazard ratio=19.6 (95% CI 2.3–171)
Fractionating Human Intelligence
What makes one person more intellectually able than another? Can the entire distribution of human intelligence be accounted for by just one general factor? Is intelligence supported by a single neural system? Here, we provide a perspective on human intelligence that takes into account how general abilities or ‘‘factors’’ reflect the functional organiza- tion of the brain. By comparing factor models of individual differences in performance with factor models of brain functional organization, we demon- strate that different components of intelligence have their analogs in distinct brain networks. Using simulations based on neuroimaging data, we show that the higher-order factor ‘‘g’’ is accounted for by cognitive tasks corecruiting multiple networks. Finally, we confirm the independence of these com- ponents of intelligence by dissociating them using questionnaire variables. We propose that intelli- gence is an emergent property of anatomically distinct cognitive systems, each of which has its own capacity
An investigation into the performance of the Adjuvant! Online prognostic programme in early breast cancer for a cohort of patients in the United Kingdom
BACKGROUND: Adjuvant! Online is an internet-based computer programme providing 10-year prognosis predictions for early breast cancer patients. It was developed in the United States, has been successfully validated in Canada, and is used in the United Kingdom and elsewhere. This study investigates the performance of Adjuvant! in a cohort of patients from the United Kingdom. METHODS: Data on the prognostic factors and management of 1065 women with early breast cancer diagnosed consecutively at the Churchill Hospital in Oxford between 1986 and 1996 were entered into Adjuvant! to generate predictions of overall survival (OS), breast cancer-specific survival (BCSS), and event-free survival (EFS) at 10 years. Such predictions were compared with the observed 10-year outcomes of these patients. RESULTS: For the whole cohort, Adjuvant! significantly overestimated OS (by 5.54%, P<0.001), BCSS (by 4.53%, P<0.001), and EFS (by 3.51%, P=0.001). For OS and BCSS, overestimation persisted across most demographic, pathologic, and treatment subgroups investigated. Differences between Adjuvant! predicted and observed EFS appeared smaller, and were significant for far fewer subgroups, only 5 out of the 28. The likely explanation for such discordance is that US breast cancer mortality rates (upon which Adjuvant! is based) appear to be systematically lower than breast cancer mortality rates in the United Kingdom. Differences in survival after recurrence would seem to be one contributory factor, with data suggesting that prognosis after relapse appears poorer in the United Kingdom. This may reflect the fact that new and more effective cancer drugs are often only approved for use in the United Kingdom many years after their adoption in the United States. CONCLUSION: The use of Adjuvant! by clinicians within the UK National Health Service is increasing, under the assumption that the programme is transferrable to the United Kingdom. At least for women treated for breast cancer at the Churchill Hospital in Oxford, however, Adjuvant!'s predictions were on the whole overoptimistic. If the findings reported here could be shown to be generalisable to other areas of the United Kingdom, then thought should perhaps be given to the development of a UK-specific version of the programme
- …