1,721,626 research outputs found
Latest results from Double Chooz
No full textDouble Chooz is a short-baseline neutrino disappearance experiment. It detects ν̄e produced in the power plant of Chooz, France, where is located. The main goal of the experiment is the measurement of θ13 mixing angle and in 2011 for the first time the experiment observed an indication for a non zero value of such an oscillation parameter. The mixing angle was successively measured using only the far detector finding the best fit value of sin2(2θ13) = 0.090−0.029+0.032. The near detector is under construction and will start data taking by the middle of 2014 allowing the reduction of the systematic errors. In this paper I make a review of the Double Chooz experiment, focusing in particular on the latest results of the measurement of the mixing angle θ13 relying on the neutron absorption on Gadolinium. I also present results proving the capability of Double Chooz to identify the ortho-positronium. This has been done in an event-by-event basis for the first time in a large liquid scintillator experiments, and can be an additional handle for the electron/positron discrimination in future detectors based on such technology
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
Glia-neuron interplay in health and disease: pharmacological evidence for this required teamwork
Full text linkGlia is a cell population highly present in the central nervous system (CNS) with the purpose, among other functions, to support neurons. In fact, many of these cells are closely in contact with neurons, actively participating to homeostatic support and synaptic transmission. For instance, astrocytes are considered integral part of the tripartite synapse. By this way, recent discoveries made possible to change perspective regarding the neuro-centric view of chronic neurodegenerative disorders, expanding the horizon to new players involved in the physiological and/or pathologic processes that take place in CNS. Better understanding the contribution of non-neuronal cells to these processes will be crucial for the development of new therapeutic approaches to counteract neurodegeneration.
Moving from these assumptions, my studies focused on evaluating the role of glial cells in inducing and triggering the inflammatory processes during neurodegeneration and, in particular, on the events that lead these cells to an activated state named reactive gliosis. Moreover, the consequences caused by these processes on neuronal survival, and in a macroscopic manner, on learning and memory, were evaluated.
To achieve such goals, I worked with different preclinical models of AD, both in vitro and in vivo, attempting to recreate at best the pathological hallmarks of pathology. In addition, since the crucial role of glial cells in the maintenance of brain homeostasis and their close connection with neuronal functioning and survival, the action of different molecules on neuroinflammation, as well as on neuronal survival, were tested
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
Design Challenges in the Development of a Hydrogen-Fueled Micro Gas Turbine Unit for Energy Generation †
No full textEnvironmental and social governance targets, as well as the global transition to cleaner renewable energy sources, push for advancements in hydrogen-based solutions for energy generators due to their high energy per unit mass (energy density) and lightweight nature. Hydrogen’s energy density and lightweight nature allow it to provide an extended range of uses without adding significant weight, potentially revolutionizing many applications. Moreover, a variety of sources, including renewable energy, can produce hydrogen, making it a potentially more sustainable option for energy storage despite its main limitations in production and transportation costs. In this framework we are proposing an innovative energy generator that might merge the benefits of batteries and hydrogen. The energy generator is based on a worldwide patented solution introduced by MIEEG s.r.l. regarding the shape of the chambers. This innovative solution can be used to design a 100% H2-fed microturbine with a high power/weight/volume ratio that works as a range extender of battery packs for a comprehensive, high-efficiency hybrid powertrain. In fact, it runs at 100,000 rpm and is designed to deliver about 100 kW in about 15 L of volume and 15 kg of weight (alternator excluded). The system is highly complex due to high firing temperatures, long life requirements, corrosion protection, mechanical and vibrational stresses, sealing, couplings, bearings, and the realization of tiny blades. This paper analyzes the main design challenges to face in the development of such complex generators, focusing on the hot gas path components, which are the most critical part of gas turbines. The contribution of additive manufacturing techniques, the adoption of special materials, and coatings have been evaluated for system improvement
Valutazione della topografia superficiale di impianti macchinati ed impianti sabbiati e mordenzati.
No full textValutazione della topografia superficiale di impianti macchinati e sabbiati e mordenzati / Atomic force microscope for implant surface study
No full textScopo del lavoro Il presente studio analizza mediante l’uso di un microscopio a forza atomica (AFM) la ruvidità di superficie di impianti macchinati messi a confronto con impianti sabbiati e mordenzati per meglio comprendere le reali condizioni fisiche osservabili sulla superficie e che influenzano l’osteointegrazione. Materiali e metodi L’AFM ricostruisce l’immagine della superficie di un campione attraverso una scansione per punti di un raggi laser consentendo di ottenere una immagine tridimensionale della superficie analizzata. Sono state realizzate scansioni a 3, 30 e 60 mm; il tipo di matrice utilizzata è stato di 256x256 per un totale di 65.536 scansioni. Risultati e conclusioni La ruvidità media di superficie risulta apprezzabilmente differente tra le due superfici implantari analizzate a netto vantaggio degli impianti sabbiati e mordenzati, ma sono necessari ulteriori studi per definire le proprietà biologiche e biomeccaniche ideali.Aim In this study surface roughness of machined implants is compared to sandblasted-acid etched implants by atomic force microscope analysis in order to understand the real physical conditions that is possible to observe on surface and that influence osseointegration. AFM reconstructs the surface image of a sample by scanning per point through laser beam and achieving a three-dimensional image. A total of 3, 30 and 60 mm scans were made and a 256x256 matrix was used for a totals of 65536 scans. Results and conclusions Mean surface roughness is different between the two analyzed surfaces is in favour of sandblasted-acid etched implants. However further studies are needed to define ideal biological and biomechanical properties
- …
