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Spherulitic concretions are very rare among carbonate concretions that generally consist of micritic carbonate. The occurrence of spherulitic concretions in Cambro-Ordovician black shales of unknown stratigraphic age on a mid-channel island in the St Lawrence Estuary in Quebec is a new example in addition to only three hitherto reported occurrences of spherulitic carbonate concretions. Their origin is still poorly understood. These concretions occur in close association with, and show various transitions to, cone-in-cone structure. The spherules, measuring 0.5 to 12 mm in diameter, consist of intergrown fine fibres of ferroan calcite and quartzine, pointing to the formation of the concretions below the sulfate-reduction zone. A phenomenological theory of spherulitic crystallization relates the thickness δ of an impurity-rich layer in front of impurity-rejecting growing crystals to the impurity-diffusion coefficient D and the growth velocity G of the crystal by δ = D/G. In spherulite-forming environments, extremely small values of δ (in the order of <10−4 cm) in conjunction with cellulation lead to spherulitic fibre growth. The theory of spherulitic crystallization is here applied to sedimentary deposits for the first time. The intimate association of calcite and quartzine in the concretions requires a chemical change from alkaline to acidic conditions, which occurs below the carbonate-reduction zone owing to the dissolution of sponge spicules or radiolarians. The transition from spherulite to the silica-free cone-in-cone structure occurs when the silica reservoir that acted as an impurity is exhausted in the crystallization process.
Most hospital payment systems based on diagnosis-related groups (DRGs) provide payments for newly approved technologies. In Germany, they are negotiated between individual hospitals and health insurances. The aim of our study is to assess the functioning of temporary reimbursement mechanisms. We used multilevel logistic regression to examine factors at the hospital and state levels that are associated with agreeing innovation payments. Dependent variable was whether or not a hospital had successfully negotiated innovation payments in 2013 (n = 1532). Using agreement data of the yearly budget negotiations between each German hospital and representatives of the health insurances, the study comprises all German acute hospitals and innovation payments on all diagnoses. In total, 32.9% of the hospitals successfully negotiated innovation payments in 2013. We found that the chance of receiving innovation payments increased if the hospital was located in areas with a high degree of competition and if they were large, had university status and were private for-profit entities. Our study shows an implicit self-controlled selection of hospitals receiving innovation payments. While implicitly encouraging safety of patient care, policy makers should favour a more direct and transparent process of distributing innovation payments in prospective payment systems.
Achieving high fracture toughness and maintaining high strength at the same time are main goals in materials science. In this work, scale-bridging fracture experiments on ultrafine-grained chromium (UFG, Cr) are performed at different length scales, starting from the macroscale over the microscale (in situ SEM) down to the nanoscale (in situ TEM). A quantitative assessment of the fracture toughness yields values of ∼3 MPa m1/2 in the frame of linear elastic fracture mechanics (LEFM) for the macrosamples. The in situ TEM tests reveal explicitly the occurrence of dislocation emission processes involved in energy dissipation and crack tip blunting serving as toughening mechanisms before intercrystalline fracture in UFG body-centered cubic (bcc) metals. In relation to coarse-grained Cr, in situ TEM tests, in this work, demonstrate the importance of strengthening grain boundaries as promising strategy in promoting further ductility and toughening in UFG bcc metals.
Preventing suicide and self-harm is a global health priority. Although there is a growing evidence base for the effectiveness of psychoanalytic and psychodynamic psychotherapies for a range of disorders, to date there has been no systematic review of its effectiveness in reducing suicidal and self-harming behaviours.
To systematically review randomised controlled trials of psychoanalytic and psychodynamic psychotherapies for suicidal attempts and self-harm.
We searched PubMed, PsycINFO, Psycharticles, CINAHL, EMBASE and the Cochrane Central Register of Controlled Trials for randomise controlled trials of psychoanalytic and psychodynamic psychotherapies for reducing suicide attempts and self-harm.
Twelve trials (17 articles) were included in the meta-analyses. Psychoanalytic and psychodynamic therapies were effective in reducing the number of patients attempting suicide (pooled odds ratio, 0.469; 95% CI 0.274–0.804). We found some evidence for significantly reduced repetition of self-harm at 6-month but not 12-month follow-up. Significant treatment effects were also found for improvements in psychosocial functioning and reduction in number of hospital admissions.
Psychoanalytic and psychodynamic psychotherapies are indicated to be effective in reducing suicidal behaviour and to have short-term effectiveness in reducing self-harm. They can also be beneficial in improving psychosocial well-being. However, the small number of trials and moderate quality of the evidence means further high-quality trials are needed to confirm our findings and to identity which specific components of the psychotherapies are effective.
Once or twice a year, an enthusiastic student will launch herself breathlessly through a door to inform one or other of us that she has discovered our names in the preface to Ngũgĩ's Decolonising the Mind. It's always amusing that such students seem to think they are telling us something we don't know, but also a pleasure to be reminded of how our lives became intertwined with Ngũgĩ's, especially between 1982, when the writer was forced into exile, and 1993, when he took up a permanent academic position at New York University. When a writer achieves the kind of status Ngũgĩ now enjoys, it's easy to forget how tenuous their intellectual and personal survival once may have seemed. Those struggles and the people and institutions that provided assistance, help shape a writer's work. As Ngũgĩ's generous acknowledgements in the preface to Decolonising the Mind remind us, ‘any work, even a literary creative work, is not the result of individual genius but the result of collective effort. There are so many inputs in the actual formation of an image, an idea. The very words we use are a product of a collective history’ (x–xi). In mapping the moments when our lives intersected with Ngũgĩ's during his years of exile, we hope to provide some insight into how those scattered encounters enriched us all.
Reinhard's friendship with Ngũgĩ dates back to the early 1970s, when Ngũgĩ spent a year at Northwestern University. Between 1967 and 1969, while Ngũgĩ was a lecturer in English at the University of Kenya at Nairobi, he had proposed the abolition of Nairobi's English Department, and in 1970 the University changed its name and scope from the Department of English to the Department of African Literature and Languages. By 1969, however, Ngũgĩ had resigned from the university in protest over violations of academic freedom (see Sander and Lindfors xix). At that point, he had published three novels – Weep Not, Child (1964), The River Between (1965) and A Grain of Wheat (1967) – and had established an international reputation in Africa, Britain and the British Commonwealth. A 1969–70 fellowship at Makerere and a 1970–71 visiting appointment at Northwestern University in Illinois provided him with funding and space to write at a moment of significant professional vulnerability.