Characterization of digital dispersive spectrometers by low coherence interferometry

We propose a procedure to determine the spectral response of digital dispersive spectrometers without previous knowledge of any parameter of the system. The method consists of applying the Fourier transform spectroscopy technique to each pixel of the detection plane, a CCD camera, to obtain its individual spectral response. From this simple procedure, the system-point spread function and the effect of the finite pixel width are taken into account giving rise to a response matrix that fully characterizes the spectrometer. Using the response matrix information we find the resolving power of a given spectrometer, predict in advance its response to any virtual input spectrum and improve numerically the spectrometer's resolution. We consider that the presented approach could be useful in most spectroscopic branches such as in computational spectroscopy, optical coherence tomography, hyperspectral imaging, spectral interferometry and analytical chemistry, among others.Fil: Martínez Matos, Ó.. Universidad Complutense de Madrid; EspañaFil: Rickenstorff, C.. Universidad Complutense de Madrid; EspañaFil: Zamora, S.. Universidad Complutense de Madrid; EspañaFil: Izquierdo, J. G.. Universidad Complutense de Madrid; EspañaFil: Vaveliuk, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Ópticas. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones Ópticas. Universidad Nacional de La Plata. Centro de Investigaciones Ópticas; Argentin

Kink fluctuation asymptotics and zero modes

In this paper we propose a refinement of the heat kernel/zeta function treatment of kink quantum fluctuations in scalar field theory, further analyzing the existence and implications of a zero energy fluctuation mode. Improved understanding of the interplay between zero modes and the kink heat kernel expansion delivers asymptotic estimations of one-loop kink mass shifts with remarkably higher precision than previously obtained by means of the standard Gilkey-DeWitt heat kernel expansion.Comment: 21 pages, 8 figures, to be published in The European Physical Journal

T-duality and the Worldvolume Solitons of Five-Branes and KK-Monopoles

We show that the fluxes of the various six-dimensional "gauge" theories are associated to below threshold bound states of D-branes with the NS-5-branes and KK-monopoles which preserve half of bulk supersymmetry. We then present the supergravity solutions that correspond to these bound states. In addition using the worldvolume solitons of IIA and IIB NS-5-branes and KK-monopoles, we investigate the sectors of the "gauge" theories that preserve one quarter of bulk supersymmetry. This leads to a generalization a supergravity solution which has the interpretation of two intersecting NS-5-branes at a 3-brane and to the construction of some of the worldvolume solitons of IIA and M-theory KK-monopoles. Furthermore, using the IIA/IIB T-duality of the bulk theories, we give the T-duality transformations of the worldvolume solitons of NS-5-branes and KK-monopoles. We find that the worldvolume 0-brane, self-dual string and 2-brane solitons of NS-5-branes appear in the same T-duality chain.Comment: 20 pages, phyzzx, minor change

Post-training depletions of basolateral amygdala serotonin fail to disrupt discrimination, retention, or reversal learning.

In goal-directed pursuits, the basolateral amygdala (BLA) is critical in learning about changes in the value of rewards. BLA-lesioned rats show enhanced reversal learning, a task employed to measure the flexibility of response to changes in reward. Similarly, there is a trend for enhanced discrimination learning, suggesting that BLA may modulate formation of stimulus-reward associations. There is a parallel literature on the importance of serotonin (5HT) in new stimulus-reward and reversal learning. Recent postulations implicate 5HT in learning from punishment. Whereas, dopaminergic involvement is critical in behavioral activation and reinforcement, 5HT may be most critical for aversive processing and behavioral inhibition, complementary cognitive processes. Given these findings, a 5HT-mediated mechanism in BLA may mediate the facilitated learning observed previously. The present study investigated the effects of selective 5HT lesions in BLA using 5,7-dihydroxytryptamine (5,7-DHT) vs. infusions of saline (Sham) on discrimination, retention, and deterministic reversal learning. Rats were required to reach an 85% correct pairwise discrimination and single reversal criterion prior to surgery. Postoperatively, rats were then tested on the (1) retention of the pretreatment discrimination pair, (2) discrimination of a novel pair, and (3) reversal learning performance. We found statistically comparable preoperative learning rates between groups, intact postoperative retention, and unaltered novel discrimination and reversal learning in 5,7-DHT rats. These findings suggest that 5HT in BLA is not required for formation and flexible adjustment of new stimulus-reward associations when the strategy to efficiently solve the task has already been learned. Given the complementary role of orbitofrontal cortex in reward learning and its interconnectivity with BLA, these findings add to the list of dissociable mechanisms for BLA and orbitofrontal cortex in reward learning

A visualization of the damage in Lead Tungstate calorimeter crystals after exposure to high-energy hadrons

The anticipated performance of calorimeter crystals in the environment expected after the planned High-Luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN has to be well understood, before informed decisions can be made on the need for detector upgrades. Throughout the years of running at the HL-LHC, the detectors will be exposed to considerable fluences of fast hadrons, that have been shown to cause cumulative transparency losses in Lead Tungstate scintillating crystals. In this study, we present direct evidence of the main underlying damage mechanism. Results are shown from a test that yields a direct insight into the nature of the hadron-specific damage in Lead Tungstate calorimeter crystals exposed to 24 GeV/c protons.Comment: 8 pages, 6 figure

On domain walls in a Ginzburg-Landau non-linear S^2-sigma model

The domain wall solutions of a Ginzburg-Landau non-linear $S^2$-sigma hybrid model are unveiled. There are three types of basic topological walls and two types of degenerate families of composite - one topological, the other non-topological- walls. The domain wall solutions are identified as the finite action trajectories (in infinite time) of a related mechanical system that is Hamilton-Jacobi separable in sphero-conical coordinates. The physical and mathematical features of these domain walls are thoroughly discussed.Comment: 26 pages, 18 figure

Price, Wage and Employment Response to Shocks: Evidence from the WDN Survey

This paper analyses information from survey data collected in the framework of the Eurosystem's Wage Dynamics Network (WDN) on patterns of firm-level adjustment to shocks. We document that the relative intensity and the character of price vs. cost and wage vs. employment adjustments in response to cost-push shocks depend - in theoretically sensible ways - on the intensity of competition in firms' product markets, on the importance of collective wage bargaining and on other structural and institutional features of firms and of their environment. Focusing on the pass-through of cost shocks to prices, our results suggest that the pass-through is lower in highly competitive firms. Furthermore, a high degree of employment protection and collective wage agreements tend to make this pass-through stronger.Wage bargaining, Labour-market institutions, Survey data, European Union.

Virtual libraries of tissue and clinical samples: potential role of a 3-D microscope.

Our international innovative teaching group from different European Universities (De Montfort University, DMU, UK; and the Spanish University of Alcalá, University Miguel Hernández and University of San Pablo CEU), in conjunction with practicing biomedical scientists in the National Health Service (UK) and biomedical researchers, are developing two complete e-learning packages for teaching and learning medical parasitology, named DMU e-Parasitology (accessible at: http://parasitology.dmu.ac.uk), and biology and chemistry, named DMU e-Biology (accessible at: http://parasitology.dmu.ac.uk/ebiology/index.htm), respectively. Both packages will include a virtual microscope with a complete library of digitised tissue images, clinical slides and cell culture slides/mini-videos for enhancing the teaching and learning of a myriad of techniques applicable to health science undergraduate and postgraduate students. Thus, these packages include detecting human parasites, by becoming familiar with their infective structures and/or organs (e.g. eggs, cysts) and/or explore pathogenic tissues stained with traditional (e.g. haematoxylin & eosin) or more modern (e.g. immunohistochemistry) techniques. The Virtual Microscope (VM) module in the DMU e-Parasitology package is almost completed (accessible at: http://parasitology.dmu.ac.uk/learn/microscope.htm) and contains a section for the three major groups of human-pathogenic parasites (Peña-Fernández et al., 2018) [1]. Digitised slides are provided with the functionality of a microscope by using the gadget Zoomify®, and we consider that they can enhance learning, as previous studies reported in the literature have reported similar sensitivity and specificity rates for identification of parasites for both digitised and real slides. The DMU e-Biology’s VM, currently in development, will provide healthy and pathological tissue samples from a range of mammalian tissues and organs. This communication will provide a description of both virtual libraries and the process of developing them. In conjunction, we will use a three-dimensional (3D) super-resolution microscopy, 3D Cell Explorer (Nanolive, Lausanne, Switzerland), to incorporate potential 3D microscopic photographs/short videos of cells to provide students with information about the spatial arrangement and morphologies of cells that are essential for life