1,721,242 research outputs found
Hydrodynamic Green functions: paradoxes in unsteady Stokes conditions and infinite propagation velocity in incompressible viscous models
No full textWe present a simple representation of the hydrodynamic Green functions grounded on the free propagation of a vector field without any constraints (such as incompressibility) coupled with a gradient gauge in order to enforce these constraints. This approach involves the solution of two scalar problems: a couple of Poisson equations in the case of the Stokes regime, and a system of diffusion/Poisson equations for unsteady Stokes flows. The explicit and closed-form expression of the Green function for unsteady Stokes flow is developed. The relevance of this approach resides in its conceptual simplicity and it enables us to focus on the intrinsic singularities (Stokesian paradoxes) associated with the propagation of the stresses in incompressible flows under unsteady Stokes conditions, determining the occurrence of power-law tails in the velocity profile arbitrarily far away from the location of the impulsive force
Generalized reflection method for the stokes equation in confined geometries. Applications to microfluidics and particle transport
Full text linkA generalized reflection method is proposed for determining the hydrodynamic resistance matrix of a rigid particle translating in a confined Stokesian fluid, by reducing its estimate to the solution of two simpler problems: (i) the singular expansion of the hydrodynamic variables due to the particle motion in the free space, represented by the Faxén operator associated with the particle geometry, and (ii) the determination of the Green function associated with the specific channel geometry. This approach extends the Stokeslet approximation to a Faxén approximation that is reliable to ratios of the particles characteristic length l to the characteristic distance d from the walls higher than the existing literature approximations, the error of which is order of O((l/d)4). Given the solution of the two above mentioned subproblems, the proposed method applies to any particle and channel geometry. The application to prolate spheroidal particles translating parallel to a plane is discussed and compared against numerical simulations
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Is it possible to optimize the use of targeted therapies in the treatment of renal cell carcinoma?
No full textPost-docetaxel therapy in castration resistant prostate cancer – the forest is growing in the desert
No full textIn Europe, prostate cancer is the most common cancer among men with 382.000 new cases and 89.000 deaths annually. Historically, androgen deprivation therapy and docetaxel based chemotherapy were the only treatments able to improve survival. Two studies have been published during last few months regarding the management of castration resistant prostate cancer (CRPC) progressed after docetaxel: for the first time second line therapies have been demonstrated to improve prognosis of these patients. The relevance of these trials is the reintroduction of chemotherapy and hormonal therapy in a disease once considered chemotherapy and castration resistant. All these data may change the traditional approach to CRPC but no evidences have came out from recently closed or ongoing clinical trials about the therapeutic algorithm. How to get oriented in this forest? We propose that patient's conditions, response and toxicities reported with previous treatments and, above all, dynamics and evolution of disease may influence the choice of subsequent therapies in docetaxel progressed CRPC. © 2012, SAGE Publications. All rights reserved
Study design and clinical evidence in mRCC: Can we save axitinib as a first-line therapy?
No full textGreen Banking in Italy: Current and Future Challenges
No full textIn the past decades, several streams of research have converged to identify the growing importance of sustainability and socio-ecological responsibility for the "nancial industry (Jeucken and Bouma 2001; Walker et!al. 2018),
devoting significant efforts to deepen our knowledge about a wide range of interlinks between "nance and the environment, sustainability, and social impact concepts, as well as their implications for a more sustainable financial syste
- …
