1,587 research outputs found
Are we heading towards a reversal of the trend for ever-greater mobility?
In most industrialised countries, it can be seen that urban mobility and car traffic have stagnated since the early 2000s. In France, the report on traffic conducted by the National Transport Accounts Commission shows a similar break in the trend, which was confirmed by household travel surveys (EMDs) in most major cities, including Lille, Lyon and Strasbourg, and later by the National Transport and Travel Survey (ENTD), which shows that the trend can be attributed primarily to people living in large urban areas and provides an overall view of mobility: trips have become less frequent (with unbroken workdays) and less exclusively taken by car (as more young adults adopt multimodal behaviours), and car ownership is decreasing in the centre of greater Paris, as, for that matter, in the centre of London. Does this levelling-off of traffic suggest that the saturation point is near (with a decoupling of traffic and income trends in the most densely populated areas or above a certain standard of living) or, rather, a cancelling out of opposite trends (continued growth in rural and suburban areas and decline amongst residents of the most densely populated areas)? Is this a structural phenomenon (population ageing, etc.) or a cyclical one linked to rising and volatile fuel prices and the recession? We shall explore these issues in the light of data collected in France, supplemented by selected data from other developed countries, and then move on to a comparison with a number of Mexican cities in order to consider the extent to which, and in what timeframe, these trends could spread southward to the emerging economies
Integer generalized inverses of incidence matrices
AbstractGraphical procedures are used to characterize the integral {1}- and {1, 2}-inverses of the incidence matrix A of a digraph, and to obtain a basis for the space of matrices X such that AXA = 0. These graphical procedures also produce the Smith canonical form of A and a full rank factorization of A using matrices with entries from {-1, 0, 1}. It is also shown how the results on incidence matrices of oriented graphs can be used to find generalized inverses of matrices of unoriented bipartite graphs
Grounding Hypnosis in Science: The 'New' APA Division 30 definition of hypnosis as a step backwards.
Every decade or so, the Division 30 of the American Psychological Association (APA) has seen fit to redefine hypnosis (Elkins, Barabasz, Council, & Spiegel, 2015; Green, Barabasz, Barrett, & Montgomery, 2005; Kirsch, 1994). In the latest attempt, the Hypnosis Definition Committee (HDC) defined hypnosis as a 'state of consciousness involving focused attention and reduced peripheral awareness characterized by an enhanced capacity for response to suggestion' (Elkins et al., 2015, p. 6). One might justifiably wonder whether important discoveries or scientific breakthroughs or novel theoretical insights motivated the impetus to update the previous definition. In fact, the recently adopted definition is neither based on any apparent empirical foundation, noris it 'new.' Moreover, it has the potential to sow the seeds of conceptual and pragmatic confusion to an area sorely in need of greater clarification
No association between human herpesvirus 6 reactivation and cryptococcosis in human immunodeficiency virus-infected patients
Do acute elevations of serum creatinine in primary care engender an increased mortality risk?
Background: The significant impact Acute Kidney Injury (AKI) has on patient morbidity and mortality emphasizes the need for early recognition and effective treatment. AKI presenting to or occurring during hospitalisation has been widely studied but little is known about the incidence and outcomes of patients experiencing acute elevations in serum creatinine in the primary care setting where people are not subsequently admitted to hospital. The aim of this study was to define this incidence and explore its impact on mortality. Methods: The study cohort was identified by using hospital data bases over a six month period. Inclusion criteria: People with a serum creatinine request during the study period, 18 or over and not on renal replacement therapy. The patients were stratified by a rise in serum creatinine corresponding to the Acute Kidney Injury Network (AKIN) criteria for comparison purposes. Descriptive and survival data were then analysed. Ethical approval was granted from National Research Ethics Service (NRES) Committee South East Coast and from the National Information Governance Board. Results: The total study population was 61,432. 57,300 subjects with ‘no AKI’, mean age 64.The number (mean age) of acute serum creatinine rises overall were, ‘AKI 1’ 3,798 (72), ‘AKI 2’ 232 (73), and ‘AKI 3’ 102 (68) which equates to an overall incidence of 14,192 pmp/year (adult). Unadjusted 30 day survival was 99.9% in subjects with ‘no AKI’, compared to 98.6%, 90.1% and 82.3% in those with ‘AKI 1’, ‘AKI 2’ and ‘AKI 3’ respectively. After multivariable analysis adjusting for age, gender, baseline kidney function and co-morbidity the odds ratio of 30 day mortality was 5.3 (95% CI 3.6, 7.7), 36.8 (95% CI 21.6, 62.7) and 123 (95% CI 64.8, 235) respectively, compared to those without acute serum creatinine rises as defined. Conclusions: People who develop acute elevations of serum creatinine in primary care without being admitted to hospital have significantly worse outcomes than those with stable kidney function
Paleomagnetic Study of Mesozoic Continental Sediments Along the Northern Tien Shan (China) and Heterogeneous Strain in Central Asia
A paleomagnetic study of rocks from the northern foot of the Tien Shan and the southern border of the Dzungar Basin, east of Urumqi (44.2°N, 86.0°E), spanning ages from middle Jurassic to early Tertiary was carried out to constrain the tectonic evolution in central Asia since Mesozoic time. Five middle Jurassic sites reveal a remagnetized direction close to the present Earth field in geographic coordinates: D = 6.6°, I = 72.6° (α_(95) = 7.4°). Thirteen out of 17 upper Jurassic and lower Cretaceous sites yield a characteristic direction (stratigraphic coordinates) of D = 12.7°, I = 48.6° (α_(95) = 5.5°). Nine of 16 upper Cretaceous and lower Tertiary sites provide a characteristic direction of D = 12.5°, I = 51.3° (α_(95) = 6.9°). The latter two directions pass fold and reversal tests. The pole positions are close to each other and to the Besse and Courtillot [1989, 1990] Eurasian apparent polar wander path, for ages ranging from 130 to 70 Ma. However, the difference in paleolatitudes amounts to about 5.9° ± 3.7°, which could indicate significant continental shortening in the Altai Mountains and perhaps further north, subsequent to India-Asia collision. The pole positions from the Dzungar Basin are close to those found for the Tarim [Li et al., 1988a], leading to an insignificant paleolatitude difference (3.0° ± 6.9°), but showing a larger difference in declination (8.6° ± 8.7°). These paleomagnetic results are compatible with a model of heterogeneous deformation in the western part of the collision zone between India and Siberia. A significant shortening in the Altai, a slight counterclockwise rotation of the Dzungar block, the westward-increasing shortening in the Tien Shan with attendant clockwise rotation of the Tarim block are all consistent with this model, in which Tibet, the Tien Shan and the Altai undergo differential strain along strike in a relay fashion, with the total India-Siberia convergence remaining approximately constant
Development and clinical validation of the Genedrive point-of-care test for qualitative detection of hepatitis C virus
Objective: Recently approved direct acting antivirals provide transformative therapies for chronic hepatitis C virus (HCV) infection. The major clinical challenge remains to identify the undiagnosed patients worldwide, many of whom live in low-income and middle-income countries, where access to nucleic acid testing remains limited. The aim of this study was to develop and validate a point-of-care (PoC) assay for the qualitative detection of HCV RNA.
Design: We developed a PoC assay for the qualitative detection of HCV RNA on the PCR Genedrive instrument. We validated the Genedrive HCV assay through a case–control study comparing results with those obtained with the Abbott RealTime HCV test.
Results: The PoC assay identified all major HCV genotypes, with a limit of detection of 2362 IU/mL (95% CI 1966 to 2788). Using 422 patients chronically infected with HCV and 503 controls negative for anti-HCV and HCV RNA, the Genedrive HCV assay showed 98.6% sensitivity (95% CI 96.9% to 99.5%) and 100% specificity (95% CI 99.3% to 100%) to detect HCV. In addition, melting peak ratiometric analysis demonstrated proof-of-principle for semiquantification of HCV. The test was further validated in a real clinical setting in a resource-limited country.
Conclusion: We report a rapid, simple, portable and accurate PoC molecular test for HCV, with sensitivity and specificity that fulfils the recent FIND/WHO Target Product Profile for HCV decentralised testing in low-income and middle-income countries. This Genedrive HCV assay may positively impact the continuum of HCV care from screening to cure by supporting real-time treatment decisions
Taking It to the Extreme:The Effect of Coalition Cabinets on Foreign Policy
Institutional constraints have been offered by some scholars as an explanation for why multiparty coalitions should be more peaceful than single-party cabinets. Yet others see the same institutional setting as a prescription for more aggressive behavior. Recent research has investigated these conflicting expectations, but with mixed results. We examine the theoretical bases for these alternative expectations about the effects of coalition politics on foreign policy. We find that previous research is limited theoretically by confounding institutional effects with policy positions, and empirically by analyzing only international conflict data. We address these limitations by examining cases of foreign policy behavior using the World Event/Interaction Survey (WEIS) dataset. Consistent with our observation that institutional constraints have been confounded with policy positions, we find that coalitions are neither more aggressive nor more peaceful, but do engage in more extreme foreign policy behaviors. These findings are discussed with regard to various perspectives on the role of institutions in shaping foreign policy behavior.</p
Collective management of environmental commons with multiple usages: a guaranteed viability approach
In this paper we address the collective management of environmental commons
with multiple usages in the framework of the mathematical viability theory. We
consider that the stakeholders can derive from the study of their own
socioeconomic problem the variables describing their different usages of the
commons and its evolution, and a representation of the desirable states for the
commons. We then consider the guaranteed viability kernel, subset of the set of
desirable states where it is possible to maintain the state of the commons even
when its evolution is represented by several conflicting models. This approach
is illustrated on a problem of lake eutrophication.Comment: 22 pages, 4 figure
- …
