Search results for "Citation"
showing 10 items of 1710 documents
Nonlinear Hanle effect in Cs vapor under strong laser excitation
2002
We report results of a theoretical and experimental study of the ground state nonlinear Hanle effect under strong laser excitation. It is shown that besides the well-known zero-magnetic field suppression of absorption on F g = F→F e = F - 1 transitions caused by population trapping, an optical pumping induced enhanced absorption occurs on F g = F→F e = F + 1 transitions for small B-fields. The latter effect becomes more pronounced for high F values. The experiment with atomic vapor of Cs (D2 line, F g = 4) confirms an increase of the spectrally unresolved fluorescence yield at zero magnetic field and 600 mW/cm2 laser intensity by 9% or 42%, when excitation occurs with linearly or circularly…
Reference density trends in the major disciplines
2018
Abstract The aim of this study was to determine whether different areas of knowledge presented different behaviour with regard to the number of references cited per journal document or if, conversely, they shared the same reference density practices. Bibliometric and bibliographic data were collected from 27,141 journals (indexed between 2001 and 2015 in the SCImago Journal & Country Rank (SJR)) and the growth rates in reference density and number of documents and journals in each category were calculated at different levels of aggregation. Our analysis identified that (a) mean reference density values in some Social Sciences and Arts and Humanities categories were equal to or higher than t…
Unsolved questions and preferred solution about living will
2018
Abstract Background Ethical problems about end-of-life medicine include a variety of issues approached in different ways by physicians and, more recently, special emphasis to this kind of ethical issues and possible answers has done by Italian National Ethical Committee in the issue named “Deep and continuous palliative sedation in the imminence of Death” (January, 2016). The debate is very critical in Intensive Care Units and Cancer Wards, where health care professionals face-off with terminally-ill patients is an outright routine; the Authors investigated their medical knowledge and ethical perception about patient critical and terminal condition to discuss the most relevant conclusions. …
Quantifying multidimensional control mechanisms of cardiovascular dynamics during multiple concurrent stressors
2021
Heartbeat regulation is achieved through different routes originating from central autonomic network sources, as well as peripheral control mechanisms. While previous studies successfully characterized cardiovascular regulatory mechanisms during a single stressor, to the best of our knowledge, a combination of multiple concurrent elicitations leading to the activation of different autonomic regulatory routes has not been investigated yet. Therefore, in this study, we propose a novel modeling framework for the quantification of heartbeat regulatory mechanisms driven by different neural routes. The framework is evaluated using two heartbeat datasets gathered from healthy subjects undergoing p…
Communication: Rotational excitation of interstellar heavy water by hydrogen molecules
2010
Cross sections and rate coefficients for low lying rotational transitions in D(2)O induced by para-H(2) collisions are presented for the first time. Calculations have been performed at the close-coupling level with the deuterated variant of the H(2)O-H(2) interaction potential of Valiron et al. [J. Chem. Phys. 129, 134306 (2008)]. Rate coefficients are presented for temperatures between 1 and 30 K and are compared to the corresponding rate coefficients for H(2)O. Significant differences caused by the isotopic substitution are observed and are attributed to both kinematics and intramolecular geometry effects. Astrophysical implications are briefly discussed in view of the very recent detecti…
Análisis del proceso de internacionalización de la investigación española en ciencia y tecnología (1980-2007)
2012
The process of scientific internationalization in Spain is based on an analysis of the growth of scientific publications and the evolution of international collaboration in Spanish scientific papers indexed in the Science Citation Index-Expanded database between 1980 and 2007. The article examines science policies in Spain together with the investments in economic and human resources devoted to research, and their effects on the internationalization process. Scholarly research in Spain has become increasingly international over the last three decades. The main features of this process have been a linear growth of productivity in terms of the number of papers published per year; a progressiv…
THE N* (1520) -> DELTA PI AMPLITUDES EXTRACTED FROM THE GAMMA P -> PI+ PI- P REACTION AND COMPARISON TO QUARK MODELS
1995
[EN] The ¿p ¿ ¿+¿¿p reaction, in combination with data from the ¿N ¿ ¿¿N reaction has been recently analyzed and allows one to obtain the s- and d-wave amplitudes for the decay into ¿¿ with absolute sign with respect to the helicity amplitudes. In addition one obtains the novel information on the momentum dependence of the amplitudes. In the present paper we show how this new information poses new constraints to quark models of hadron structure. In particular we show that the signs and the momentum dependence of these amplitudes coincide with those given by non relativistic constituent quark models. The absolute values provided by these models agree only qualitatively, and a discussion is d…
High Rate of Studies with Level 1 and 2 Evidence among the 100 Most Cited Articles in Lumbar Spinal Stenosis.
2021
Abstract Background To date, no study has used bibliometric analysis to review the most influential articles in lumbar spinal stenosis. The objective of this study was to identify and analyze the characteristics and the level of evidence of the 100 most cited articles on lumbar spinal stenosis Methods The Thomson Reuters Web of Science was accessed to find the 100 most cited articles on lumbar spinal stenosis. For each article, we recorded the number and density of citations, authors, country, journals and years, department, level of evidence, type of study, and if it was part of any multicenter studies. Results Until January 2017, the 100 most cited articles accumulated 11,136 citations (a…
Sperm activation and sperm-egg interaction
2006
Different steps of sperm activation such as acrosomal reaction and capacitation are described in details. The molecules involved in sperm-egg interaction are also reported.
Optical-sectioning improvement in two-color excitation scanning microscopy
2004
We present a new beam-shaping technique for two-color excitation fluorescence microscopy. We show that by simply inserting a properly designed shaded-ring filter in the illumination beam of smaller wavelength, it is possible to improve the effective optical sectioning capacity of such microscopes by 23%. Such an improvement is obtained at the expense of only a very small increasing of the overall energy in the point-spread-function sidelobes. The performance of this technique is illustrated by a numerical imaging simulation.