805 research outputs found

    A Neuroimaging Web Interface for Data Acquisition, Processing and Visualization of Multimodal Brain Images

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    Structural and functional brain images are generated as essential modalities for medical experts to learn about the different functions of the brain. These images are typically visually inspected by experts. Many software packages are available to process medical images, but they are complex and difficult to use. The software packages are also hardware intensive. As a consequence, this dissertation proposes a novel Neuroimaging Web Services Interface (NWSI) as a series of processing pipelines for a common platform to store, process, visualize and share data. The NWSI system is made up of password-protected interconnected servers accessible through a web interface. The web-interface driving the NWSI is based on Drupal, a popular open source content management system. Drupal provides a user-based platform, in which the core code for the security and design tools are updated and patched frequently. New features can be added via modules, while maintaining the core software secure and intact. The webserver architecture allows for the visualization of results and the downloading of tabulated data. Several forms are ix available to capture clinical data. The processing pipeline starts with a FreeSurfer (FS) reconstruction of T1-weighted MRI images. Subsequently, PET, DTI, and fMRI images can be uploaded. The Webserver captures uploaded images and performs essential functionalities, while processing occurs in supporting servers. The computational platform is responsive and scalable. The current pipeline for PET processing calculates all regional Standardized Uptake Value ratios (SUVRs). The FS and SUVR calculations have been validated using Alzheimer\u27s Disease Neuroimaging Initiative (ADNI) results posted at Laboratory of Neuro Imaging (LONI). The NWSI system provides access to a calibration process through the centiloid scale, consolidating Florbetapir and Florbetaben tracers in amyloid PET images. The interface also offers onsite access to machine learning algorithms, and introduces new heat maps that augment expert visual rating of PET images. NWSI has been piloted using data and expertise from Mount Sinai Medical Center, the 1Florida Alzheimer’s Disease Research Center (ADRC), Baptist Health South Florida, Nicklaus Children\u27s Hospital, and the University of Miami. All results were obtained using our processing servers in order to maintain data validity, consistency, and minimal processing bias

    Extreme orbital evolution from hierarchical secular coupling of two giant planets

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    Observations of exoplanets over the last two decades have revealed a new class of Jupiter-size planets with orbital periods of a few days, the so-called "hot Jupiters". Recent measurements using the Rossiter-McLaughlin effect have shown that many (~ 50%) of these planets are misaligned; furthermore, some (~ 15%) are even retrograde with respect to the stellar spin axis. Motivated by these observations, we explore the possibility of forming retrograde orbits in hierarchical triple configurations consisting of a star-planet inner pair with another giant planet, or brown dwarf, in a much wider orbit. Recently Naoz et al. (2011) showed that in such a system, the inner planet's orbit can flip back and forth from prograde to retrograde, and can also reach extremely high eccentricities. Here we map a significant part of the parameter space of dynamical outcomes for these systems. We derive strong constraints on the orbital configurations for the outer perturber that could lead to the formation of hot Jupiters with misaligned or retrograde orbits. We focus only on the secular evolution, neglecting other dynamical effects such as mean-motion resonances, as well as all dissipative forces. For example, with an inner Jupiter-like planet initially on a nearly circular orbit at 5 AU, we show that a misaligned hot Jupiter is likely to be formed in the presence of a more massive planetary companion (> 2 MJ) within 140 AU of the inner system, with mutual inclination 50 degrees and eccentricity above 0.25. This is in striking contrast to the test-particle approximation, where an almost perpendicular configuration can still cause large eccentricity excitations, but flips of an inner Jupiter-like planet are much less likely to occur. The constraints we derive can be used to guide future observations, and, in particular, searches for more distant companions in systems containing a hot Jupiter.Comment: To appear in the Astrophysical Journa

    Uncovering a Role for SK2 in Angelman Syndrome

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    Angelman syndrome is a severe neurodevelopmental disorder caused by mutations in UBE3A. Sun et al. (2015) report SK2 as a UBE3A substrate and provide insight into the molecular mechanisms that might underlie impaired neuronal function in individuals affected by Angelman syndrome

    Site Fidelity and Residency of Tursiops truncatus off the Aragua Coast, Venezuela-First Records of Long Residency

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    This study represents the first comprehensive analysis of the residency patterns of a coastal population of bottlenose dolphin off the coast of Aragua, Venezuela, over a multi-year period. Using photo-identification, the most recent study (2019-2020) identified 56 individuals with the time between encounters from one to 344 days between the first and last sighting. Site Fidelity (SF) and Residence (RES) indices were calculated and Agglomerative Hierarchical Clustering (AHC) modeling was performed, with three patterns of residence obtained: resident (25%), semiresident (17.86%) and transient (57.14%). These results were contrasted with remodeled data from a previous study (2006-2007), showing similar patterns: resident (24.44%), semi-resident (28.89%) and transient (46.67%). Importantly, two individuals were found to have been resident over the extended period. A breeding female sighted for the first time in 2004 and again in 2020 (16 years) and the other from 2005 to 2020 (15 years). This region is an important area for marine mammals, known to support a resident reproductive population over many years, as well seabirds, sea turtles, whale sharks and fishermen. We recommend that consideration be given to designating the waters as a Marine Protected Area to safeguard the existing population and provide benefit to the surrounding marine environment

    A Method to Shorten Signals in SM-OFDM

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    Spatial modulation (SM) added to traditional OFDM communications has been intensively studied as a candidate transmission method to convey high-speed, low-delay, powerefficient and high-mobility 5G communications in a reliable basis. This approach implies the use of multiple antennas at the transmitter. Then, the fundamental aspect revised in this work takes into account that in a single-carrier SM system, the selection of the active transmit antenna according to (part of) the information bits makes it possible to use a single power amplifier (PA) that is switched among the available antennas. On the other hand, in a conventional SM-OFDM system, every antenna needs to be continuously active as the index information is typically different for each subcarrier. Consequently, we propose a transmission scheme that precodes the information symbols in frequency domain, such that the global symbol period is split into partitions that enable a sequential operation of antennas which can be fed by a single PA. In addition, it is possible to establish that the proposed approach tends to be more robust against disturbances observed in high mobility environments.Sociedad Argentina de Informática e Investigación Operativa (SADIO

    A Natural Alternative Treatment for Urinary Tract Infections: Itxasol©, the Importance of the Formulation

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    Genito-urinary tract infections have a high incidence in the general population, being more prevalent among women than men. These diseases are usually treated with antibiotics, but very frequently, they are recurrent and lead to the creation of resistance and are associated with increased morbidity and mortality. For this reason, it is necessary to develop new compounds for their treatment. In this work, our objective is to review the characteristics of the compounds of a new formulation called Itxasol© that is prescribed as an adjuvant for the treatment of UTIs and composed of β-arbutin, umbelliferon and n-acetyl cysteine. This formulation, based on biomimetic principles, makes Itxasol© a broad-spectrum antibiotic with bactericidal, bacteriostatic and antifungal properties that is capable of destroying the biofilm and stopping its formation. It also acts as an anti-inflammatory agent, without the adverse effects associated with the recurrent use of antibiotics that leads to renal nephrotoxicity and other side effects. All these characteristics make Itxasol© an ideal candidate for the treatment of UTIs since it behaves like an antibiotic and with better characteristics than other adjuvants, such as D-mannose and cranberry extracts

    A Method to Shorten Signals in SM-OFDM

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    Spatial modulation (SM) added to traditional OFDM communications has been intensively studied as a candidate transmission method to convey high-speed, low-delay, powerefficient and high-mobility 5G communications in a reliable basis. This approach implies the use of multiple antennas at the transmitter. Then, the fundamental aspect revised in this work takes into account that in a single-carrier SM system, the selection of the active transmit antenna according to (part of) the information bits makes it possible to use a single power amplifier (PA) that is switched among the available antennas. On the other hand, in a conventional SM-OFDM system, every antenna needs to be continuously active as the index information is typically different for each subcarrier. Consequently, we propose a transmission scheme that precodes the information symbols in frequency domain, such that the global symbol period is split into partitions that enable a sequential operation of antennas which can be fed by a single PA. In addition, it is possible to establish that the proposed approach tends to be more robust against disturbances observed in high mobility environments.Sociedad Argentina de Informática e Investigación Operativa (SADIO

    Interventions on the social dimension of people with chronic heart failure: a systematic review of randomized controlled trials

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    Aims The symptom burden of patients with chronic heart failure (CHF), together with social determinants and psychosocial factors, results in limitations to maintain adequate social life and roles, participate in social events and maintain relationships. This situation's impact on health outcomes makes it of utmost importance to develop meaningful social networks for these patients. The primary objective aimed to identify randomized controlled trials that impact the social dimension of people with CHF. The secondary objectives were to analyze the methodological quality of these interventions, establish their components, and synthesize their results. Methods and results A systematic review following PRISMA guidelines was conducted in Pubmed, Scopus, Cochrane CENTRAL, PsychINFO, and CINAHL databases between 2010 and February 2022. The Revised Cochrane risk-of-bias tool for randomized trials was used. The protocol was registered in PROSPERO. Eight randomized controlled trials were identified, among which two were at ‘high risk of bias.’ Interventions were synthesized according to the following categories: delivery format, providers and recipients, and the intervention content domains. Half of the studies showed statistical superiority in improving the intervention group's social support in people with CHF. Conclusion This review has highlighted the scarcity of interventions targeting the social dimension of people with CHF. Interventions have been heterogeneous, which limits the statistical combination of studies. Based on narrative review and vote counting, such interventions could potentially improve social support and self-care, which are important patient reported outcomes, thus warrant further research. Future studies should be co-created with patients and families to be adequately targeted

    Experiencing the possibility of near death on a daily basis: A phenomenological study of patients with chronic heart failure

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    Background: Chronic heart failure (CHF) is a syndrome that greatly impacts people’s lives. Due to the poor prognosis of CHF, together with the frequent exacerbations of symptoms, death is a topic that is very present in the lives of patients with CHF. Objective: To explore thoughts about death experienced by patients with chronic heart failure in their daily lives. Methods: A hermeneutic phenomenological study was carried out. Conversational interviews were conducted with 20 outpatients with chronic heart failure. Analysis of the responses was based on the method proposed by van Manen. Results: From the analysis, four main themes emerged: (1) Feeling afraid of the possibility of dying; (2) Acceptance of the possibility of death; (3) Desiring death for relief from suffering; and (4) Striving to continue living to enjoy family. Conclusions: This study presents, as a novel finding, that people with CHF experience the possibility of near death on a daily basis. This experience, which they must encounter on their own, makes them afraid. In addition, some of them, in view of the discomfort they are living, wish to die, with some even considering committing suicide
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