59 research outputs found
Interference profiles with multiple spherical waves: general case
Characteristics of multiple-beam interference fringes, as in a Fabry–Perot interferometer with monochromatic light, are analyzed. The optical path and the optical-path difference between interfering beams are calculated for the most general case. Different refractive indices in the inner and outer media, and arbitrary locations of the light source and the point of observation, are taken into account. An expression for the impulse response of the system is given. The results obtained from experimental tests confirm the theoretical predictions
About Superluminal motions and Special Relativity: A Discussion of some recent Experiments, and the solution of the Causal Paradoxes
Some experiments, performed at Berkeley, Cologne, Florence, Vienna, Orsay,
Rennes, etc., led to the claim that something seems to travel with a group
velocity larger than the speed c of light in vacuum. Various other experimental
results seem to point in the same direction: For instance, localized wavelet-
type solutions to Maxwell equations have been found, both theoretically and
experimentally, that travel with superluminal speed. [Even muonic and
electronic neutrinos [it has been proposed] might be "tachyons", since their
square mass appears to be negative]. With regard to the first-mentioned
experiments, it was recently claimed by Guenter Nimtz that those results with
evanescent waves (or tunneling photons) imply superluminal signal and impulse
transmission, and therefore violate Einstein causality. In this note we want to
stress that, on the contrary, all such results do not place relativistic
causality in jeopardy, even if they referred to actual tachyonic motions: In
fact, Special Relativity can cope even with superluminal objects and waves. For
instance, it is possible (at least in microphysics) to solve also the known
causal paradoxes, devised for faster than light motion, although this is not
widely recognized yet. Here we show, in detail and rigorously, how to solve the
oldest causal paradox, originally proposed by Tolman, which is the kernel of
many further tachyon paradoxes (like J.Bell's, F.A.E.Pirani's, J.D.Edmonds' and
others'). The key to the solution is a careful application of tachyon
mechanics, as it unambiguously follows from special relativity. At Last, in one
of the two Appendices, we propose how to evaluate the group-velocity in the
case of evanescent waves. [PACS nos.: 03.30.+p; 03.50.De; 41.20.Jb; 73.40.Gk;
84.40.Az; 42.82.Et ]Comment: LaTeX file: 26 pages, with 5 Figures (and two Appendices). The
original version of this paper appeared in the Journal below
Adaptation of NS cells growth and differentiation to high-throughput screening-compatible plates
Peer reviewedPublisher PD
Application of Vertical Brackets in Orthodontial Treatments: A Laser Speckle Study
This paper reports the application of a laser speckle technique for orthodontial studies. The purpose of these studies is to certify the validity of a proposal related with a new type of apparatus, and the methodology to be used in orthodontial treatments.
(Párrafo extraído a modo de resumen)</em
Medida holográfica de deformaciones utilizando un registro interferométrico
Se presenta en esta comunicación una nueva técnica holográfica por doble exposición, para el estudio de deformaciones colocando un interferograma entre el objeto a analizar y un medio de registro fotográfico. Este novedoso método permite la obtención simultánea de los datos cuantitativos y de la estructura topográfica de la deformación. Se destaca su simplicidad, ya que no requiere más condiciones de estabilidad que las usadas en todo proceso holográfico, emplea un número mínimo de elementos ópticos y no necesita ser llevada a cabo en un laboratorio, pudiendo ser usada como herramienta de fácil manejo para el control de calidad, ofreciendo la ventaja de poder trabajar tanto a tiempo diferido como a tiempo real
ANO3 as a Cause of Early‐Onset Chorea Combined with Dystonia: Illustration of Phenotypic Evolution
Here, we signpost a case of a childhood-onset chorea-dominant phenotype later evolved into a dystonia-dominant phenotype during adulthood, in a subject carrying a missense pathogenic variant (c.1528 G > A; p.Glu510Lys)1 in the anoctamin 3 protein-coding gene (ANO3, DYT24, OMIM 610110).
Economic Evaluation of Different Organizational Models for the Management of Patients with Hepatitis C
BACKGROUND: Access to Directly Acting Antivirals (DAAs) for Hepatitis C Virus (HCV) treatment in Italy was initially restricted to severe patients. In 2017, AIFA expanded access to all patients, to achieve elimination by 2030.AIM: To investigate the impact of different hospitals’ organizational models on elimination timing, treatment capacity and direct costs.METHODS: Most Regional healthcare systems in Italy deploy a Center of Excellence (CoE) organizational model, where patients are referred to a single major hospital in the area, which is the only one that can prescribe and deliver DAAs. The study was conducted at Bergamo’s (Lombardy, Italy) Papa Giovanni XXIII hospital (PG-23), which deploys a Hub&Spoke model: the Hub (PG-23) prescribes and delivers DAAs while Spokes (four smaller hospitals) can only prescribe them. The study compares the two models (CoE vs. H&S). Patient journey and workloads were mapped and quantified through interviews with hospital stakeholders. Cost data were collected through the hospital’s IT system; the sample comprised 2,277 HCV patients, over one year.RESULTS: The study calculated the average cost to treat HCV patients (~ € 1,470 per patient). Key cost drivers are lab tests (60%) and specialist visits (30%). Over one year, H&S can treat 68% more patients than CoE. As deferred patients absorb up to 40% of total costs, the “Optimized” model was designed by streamlining specialists’ visits and involving general practitioners during follow-up. “Optimized” model increases treatment capacity and reduces costs of deferred patients by 72% vs CoE.CONCLUSION: The study demonstrates the importance of organizational models in efficiently achieving 2030 elimination
Application of Vertical Brackets in Orthodontic Treatments: A Laser Speckle Study
This paper reports the application of a laser speckle technique to orthodontic studies. The purpose of these studies is to certify the validity of a proposal related with a new type of apparatus, and the methodology to be used in orthodontic treatments.Trabajo publicado en Guimaraes, W. O. N.; Lin, Chhui-Tsu; Mooradian, A. (eds.). Lasers and Applications. Springer-Verlag Berlin Heidelberg, 1981. Springer Series in Optical Sciences (SSOS), vol. 26.Facultad de OdontologíaCentro de Investigaciones Óptica
Progressive right ventricular dysfunction and exercise impairment in patients with heart failure and diabetes mellitus: insights from the T.O.S.CA. Registry
Findings from the T.O.S.CA. Registry recently reported that patients with concomitant chronic heart failure (CHF) and impairment of insulin axis (either insulin resistance-IR or diabetes mellitus-T2D) display increased morbidity and mortality. However, little information is available on the relative impact of IR and T2D on cardiac structure and function, cardiopulmonary performance, and their longitudinal changes in CHF
Repensando el Estado como institución. Poder central, cultura local y relaciones centro-periferia en las interpretaciones de Juan Maiguashca y el debate Schwarz-Carvalho Franco.
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