Doppler Domain Decomposition of the Underwater Acoustic Channel Response

Most underwater applications are very sensitive to environmental perturbations like source/receiver motion and surface variations. In real conditions, the transmitted signal reaches the receiver through different paths where each path is affected by different environmental perturbations. Due to the interaction with these environmental variations different Doppler is induced in each path. By observing the Doppler for the whole signal it is not possible to determine the contribution of each environmental variation. The main goal of this paper is to isolate different paths and analyse the effects of the environmental variations on each path in terms of the induced Doppler. A new technique called Time Windowed Doppler Spectrum is proposed which has been found very effective in tracking the Doppler due to each path separately. By using this technique it can be shown that it is possible to distinguish between surface reflected and direct path by observing the Doppler variations associated with each path. The surface induced Doppler was observed using this technique by analysing the temporal evolution of the surface reflected path. The surface variability effects the Doppler in terms of stretching and shortening the path between the transmitter and receiver. The data processed in this paper was acquired during CALCOMM'10 Experiment which took place in June 2010 at the south coast of Portugal

The TV-APM interface: a web service for collaborative modeling

Current development of Internet access, together with available zero-cost Open Source applications (like, for instance, PHP, Python, etc.) can be integrated in order to minimize the constrains induced by the geographical separation of international centers, which collaborate in a given project. The advantage of such approach lies in the sharing of common analysis methods, without particular constrains to specific directions of analysis. The discussion presented in this paper describes the Time Variable Acoustic Propagation Model (TV-APM) web interface, which was created as a collaborative service of acoustic modeling for the participants of the PHITOM and UAN projects. This paper describes the general architecture of the interface, its current shortcomings and advantages, and presents a set of modeling results for short range acoustic propagation, which accounts for source–array and sea surface motion

Quantum dots based on spin properties of semiconductor heterostructures

The possibility of a novel type of semiconductor quantum dots obtained by spatially modulating the spin-orbit coupling intensity in III-V heterostructures is discussed. Using the effective mass model we predict confined one-electron states having peculiar spin properties. Furthermore, from mean field calculations (local-spin-density and Hartree-Fock) we find that even two electrons could form a bound state in these dots.Comment: 9 pages, 3 figures. Accepted in PRB (Brief Report) (2004

Combination of DROOL rules and Protégé knowledge bases in the ONTO-H annotation tool

ONTO-H is a semi-automatic collaborative tool for the semantic annotation of documents, built as a Protégé 3.0 tab plug-in. Among its multiple functionalities aimed at easing the document annotation process, ONTO-H uses a rule-based system to create cascading annotations out from a single drag and drop operation from a part of a document into an already existing concept or instance of the domain ontology being used for annotation. It also gives support to the detection of name conflicts and instance duplications in the creation of the annotations. The rule system runs on top of the open source rule engine DROOLS and is connected to the domain ontology used for annotation by means of an ad-hoc programmed Java proxy

Resolution improvement of brain PET images using prior information from MRI: clinical application on refractory epilepsy

An important counterpart of clinical Positron Emission Tomography (PET) for early diagnosis of neurological diseases is its low resolution. This is particularly important when evaluating diseases related to small hypometabolisms such as epilepsy. The last years, new hybrid systems combining PET with Magnetic Resonance (MR) has been increasingly used for several different clinical applications. One of the advantages of MR is the production of high spatial resolution images and a potential application of PET-MR imaging is the improvement of PET resolution using MR information. A potential advantage of resolution recovery of PET images is the enhancement of contrast delivering at the same time better detectability of small lesions or hypometabolic areas and more accurate quantification over these areas. Recently, Shidahara et al (2009) proposed a new method using wavelet transforms in order to produce PET images with higher resolution. We optimised Shidahara’s method (SFS-RR) to take into account possible shortcomings on the particular clinical datasets, and applied it to a group of patients diagnosed with refractory epilepsy. FDG-PET and MRI images were acquired sequentially and then co-registered using software tools. A complete evaluation of the PET/MR images was performed before and after the correction, including different parameters related with PET quantification, such as atlas-based metabolism asymmetry coefficients and Statistical Parametric Mapping results comparing to a database of 87 healthy subjects. Furthermore, an experienced physician analyzed the results of non-corrected and corrected images in order to evaluate improvements of detectability on a visual inspection. Clinical outcome was used as a gold standard. SFS-RR demonstrated to have a positive impact on clinical diagnosis of small hypometabolisms. New lesions were detected providing additional clinically relevant information on the visual inspection. SPM sensitivity for the detection of small lesions was increased from 70% to 90%

Modeling arrival scattering due to surface roughness

Signal scattering due to surface roughness constitutes one of the most important modeling problems in underwater acoustics when dealing with signal processing at large frequencies (i.e. above 1 kHz). Such modeling requires, in particular, realistic predictions of the ocean surface, which is usually perturbed by the propagation of swells and wind driven surface waves. Most of experimental studies had been dealing with short-range propagation, although it still remains unclear the separated impact of periodic vs. stochastic surface roughness on the arrival structure of received signals. The main purpose of the discussion presented in this paper is to clarify such issues through the calculation of impulse responses at high frequencies, at short and large ranges, using a ray tracing acustic propagation model. The results of the simulations are expected to improve strategies of signal processing when scattering affects the received signal

Underwater Acoustic simulations with a time variable acoustic propagation model

The Time Variable Acoustic Propagation Model (TV-APM) was developed to simulate underwater acoustic propagation in time-variable environments. Such environment variability induces a strong Doppler channel spread, which is an important factor to test and evaluate the performance of equalization algorithms. In current simulations, Doppler spread is usually included a posteriori in a stationary Acoustic Propagation Model (APM), and is designed for specific environmental parameters such as source-receiver range variability or surface motion. However, environmental variations affect Doppler spread in a complex manner, and an accurate TV-APM simulation for time varying channels, being performed at the same sampling rate as the transmitted signal, would require a large number of runs at high frequencies. A strategy in the current implementation of the TV-APM was developed to reduce the number of runs, while preserving the variable-channel Doppler spread. Simulations were done to draw a performance map for a given equalizer in a given environment and the results revealed that the TV-APM is a useful prediction tool of communication equalizers performance

Post-operative treatment in breast cancer diagnosed patient

[Resumen] El cáncer, que es la causa más frecuente de muerte prematura y evitable en la Unión Europea, constituye un problema importante de salud pública. Dentro del colectivo femenino, uno de los cánceres más frecuentes y que más preocupan a la población es el cáncer de mama. En Europa se estima que 8 de cada 100 mujeres desarrollarán está enfermedad antes de los 75 años. La cirugía y la radioterapia pueden provocar alteraciones postquirúrgicas que a la larga disminuyen la calidad de vida de estas pacientes. Con este artículo se pretende realizar una búsqueda bibliográfica que clarifique las alteraciones postquirúrgicas en este tipo de paciente y el tratamiento fisioterápico que se emplea para tratarlas. Todos los estudios analizados indican la aparición de alteraciones glenohumerales en estos pacientes y los beneficios que el tratamiento de fisioterapia les acarrea, ningún estudio atestigua resultados contrarios. Si bien es cierto que no existe ningún estudio con la suficiente muestra para aclarar que tipo de pacientes (edad, condición física, tipo de cirugía, radioterapia recibida) presentan una incidencia mayor de estas alteraciones.[Abstract] Cancer is the most frequent cause of premature and avoidable death in the European Union, constitutes an important problem of public health. Within the feminine group, one of the most frequent cancers is the breast cancer. In Europe esteem that 8 of each 100 women will develop is disease before the 75 years. Surgery and radiotherapy can cause postsurgical alterations that diminish the quality of life of these patients. With this article it is tried to make a bibliographical search that clarify the postsurgical alterations in this type of patient and the physical therapy treatment used to treat them. All the analyzed studies indicate the appearance of shoulder alterations in these patients and the benefits that the physical therapy treatment carries to them, no study testifies opposite results. Although it is certain that any study with the sufficient sample does not exist to clarify wich type of patients (age, physical training conditions, type of surgery, radiotherapy recieved) presents a greater incidence of these alterations

Synthesis of Catechol Derived Rosamine Dyes and Their Reactivity toward Biogenic Amines

Functional organic dyes play a key role in many fields, namely in biotechnology and medical diagnosis. Herein, we report two novel 2,3- and 3,4-dihydroxyphenyl substituted rosamines (3 and 4, respectively) that were successfully synthesized through a microwave-assisted protocol. The best reaction yields were obtained for rosamine 4, which also showed the most interesting photophysical properties, specially toward biogenic amines (BAs). Several amines including n- and t-butylamine, cadaverine, and putrescine cause spectral changes of 4, in UV–Vis and fluorescence spectra, which are indicative of their potential application as an effective tool to detect amines in acetonitrile solutions. In the gas phase, the probe response is more expressive for spermine and putrescine. Additionally, we found that methanolic solutions of rosamine 4 and n-butylamine undergo a pink to yellow color change over time, which has been attributed to the formation of a new compound. The latter was isolated and identified as 5 (9−aminopyronin), whose solutions exhibit a remarkable increase in fluorescence intensity together with a shift toward more energetic wavelengths. Other 9-aminopyronins 6a, 6b, 7a, and 7b were obtained from methanolic solutions of 4 with putrescine and cadaverine, demonstrating the potential of this new xanthene entity to react with primary amines.Financial support from PT national funds (FCT/MCTES, Fundação para a Ciência e a Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) through the project PTDC/QUI-QOR/29426/2017. The research team would like to thank the projects UIDB/50006/2020, PTDC/QUI-QIN/28142/2017 and Grant BU263P18 (from the Junta de Castilla y León, Consejería de Educación y Cultura y Fondo Social Europeo). F. M. -S. gratefully acknowledges FCT (Portugal’s Foundation for Science and Technology) within grant DFA/BD/9136/2020. A.M.G.S. and A.L. thank FCT for the program DL 57/2016 – Norma transitória

Dataset of the sperm proteome of stallions with different motility

This paper provides a detailed set of data on how the stal-lion sperm proteome differs among stallions with different sperm motilities, although within normal ranges. Findings distinguish proteins that may help to identify stallions of su-perior sperm motility. Sperm proteins were analyzed using a UHPLC/MS/MS system comprising of an Agilent 1290 in-finity series UHPLC coupled to an Agilent 6550 Q-TOF mass spectrometer (Agilent Technologies, Santa Clara, CA, USA). These data can be used to disclose potential targets to iden-tify good sperm samples and to study specific pathways in-volved in the regulation of sperm motility. This data article is linked to the paper "Proteins involved in mitochondrial metabolic functions and fertilization predominate in stallions with better motility Journal of Proteomics 247:104335 doi: 10.1016/j.jprot.2021.104335".(c) 2022 The Author(s). Published by Elsevier Inc.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/