1,148 research outputs found

    Normal and impaired reflexive orienting of attention after central nonpredictive cues

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    Recent studies suggest that stimuli with directional meaning can trigger lateral shifts of visuospatial attention when centrally presented as noninformative cues. We investigated covert orienting in healthy participants and in a group of 17 right braindamaged patients (9 with hemispatial neglect) comparing arrows, eye gaze, and digits as central nonpredictive cues in a detection task. Orienting effects elicited by arrows and eye gaze were overall consistent in healthy participants and in right brain-damaged patients, whereas digit cues were ineffective. Moreover, patients with neglect showed, at the shortest delay between cue and target, a disengage deficit for arrow cueing whose magnitude was predicted by neglect severity. We conclude that the peculiar form of attentional orienting triggered by the directional meaning of arrow cues presents some features previously thought to characterize only the stimulus-driven (exogenous) orienting to noninformative peripheral cues

    A Study on Learnability for Rigid Lambek Grammars

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    We present basic notions of Gold's "learnability in the limit" paradigm, first presented in 1967, a formalization of the cognitive process by which a native speaker gets to grasp the underlying grammar of his/her own native language by being exposed to well formed sentences generated by that grammar. Then we present Lambek grammars, a formalism issued from categorial grammars which, although not as expressive as needed for a full formalization of natural languages, is particularly suited to easily implement a natural interface between syntax and semantics. In the last part of this work, we present a learnability result for Rigid Lambek grammars from structured examples

    Handle Anywhere: A Mobile Robot Arm for Providing Bodily Support to Elderly Persons

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    Age-related loss of mobility and increased risk of falling remain important obstacles toward facilitating aging-in-place. Many elderly people lack the coordination and strength necessary to perform common movements around their home, such as getting out of bed or stepping into a bathtub. The traditional solution has been to install grab bars on various surfaces; however, these are often not placed in optimal locations due to feasibility constraints in room layout. In this paper, we present a mobile robot that provides an older adult with a handle anywhere in space - "handle anywhere". The robot consists of an omnidirectional mobile base attached to a repositionable handle. We analyze the postural changes in four activities of daily living and determine, in each, the body pose that requires the maximal muscle effort. Using a simple model of the human body, we develop a methodology to optimally place the handle to provide the maximum support for the elderly person at the point of most effort. Our model is validated with experimental trials. We discuss how the robotic device could be used to enhance patient mobility and reduce the incidence of falls.Comment: 8 pages, 10 figure

    Unrevealing Parasitic Trophic Interactions— A Molecular Approach for Fluid-Feeding Fishes

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    Fish diets have been traditionally studied through the direct visual identification of food items found in their stomachs. Stomach contents of Vandeliinae and Stegophilinae (family Trichomycteridae) parasite catfishes, however, cannot be identified by usual optical methods due to their mucophagic, lepidophagic, or hematophagic diets, in such a way that the trophic interactions and the dynamics of food webs in aquatic systems involving these catfishes are mostly unknown. The knowledge about trophic interactions, including difficult relation between parasites and hosts, are crucial to understand the whole working of food webs. In this way, molecular markers can be useful to determine the truly hosts of these catfishes, proving a preference in their feeding behavior for specific organisms and not a generalist. Sequences of cytochrome oxidase subunit 1 (COI) were successfully extracted and amplified from mucus or scales found in the stomach contents of two species of stegophilines, Homodiaetus anisitsi, and Pseudostegophilus maculatus, to identify the host species. The two species were found to be obligatory mucus-feeders and occasionally lepidophagic. Selection of host species is associated to host behavior, being constituted mainly by substrate-sifting benthivores. Characiformes are preferred hosts, but host choice depends on what characiform species are available in their environments, usually corresponding to the most abundant species. This is the first time that host species of parasitic fishes bearing mucophagous habits are identified, and demonstrates the effectiveness of the extraction and amplification of mitochondrial DNA from the ingested mucus in gut contents. The molecular markers effectively allowed determine parasite preferences and helps in better understanding the food web and trophic interaction on which fish species are involved. Despite, the methodology applied here can be used for an infinitive of organisms improving ecological trophic studies

    Determination of perfluoroalkyl acids in different tissues of graminaceous plants

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    A method for the determination of 12 perfluoroalkylacids (PFAA) in vegetal samples was proposed. The analytical procedure was developed to optimize the detention of short-chain PFAA (C<8) due to their higher potential to be translocated and bioaccumulated in plants than long-chain congeners. The method, based on ultrasonic extraction, clean-up and HPLC-MS/MS analysis, determined PFAA in the different plant tissues allowing to study the PFAA distribution and partition in vegetal compartments. The performance of this analytical procedure was validated by analysing samples (root, stem and leaf) of reed grass. The validated method was then applied to graminaceous plants from an agricultural area impacted by a fluorochemical plant discharge (Northern Italy). The PFAA congeners were detected in the most of samples with PFAA concentrations in whole plant ranging from < LOD to 10.4 ng g-1 ww and with a greater rate of PFAA accumulation in corn cob than corn kernel. The proposed approach is particularly relevant in edible plant investigation because PFAA levels recorded in the comestible fractions provide information for human risk assessment due to vegetable consumption. Furthermore data on the remaining not edible parts, intended for breeding forage, are also useful for the assessment of the PFAA transfer in the breeding trophic chain

    On the development of a façade-integrated solar water storage

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    The integration of active solar thermal technologies into building envelopes has recently received a rising attention, promoted within international projects as IEA Task 56 or Cost Action 1403. Although the façade integration of solar thermal collectors is a long debated topic, less attention is paid to the building integration of solar water storages. The scope of the paper is to highlight the main barriers experienced in the development of a façade-integrated solar water storage. This activity is a part of the SunRise project that aims to develop new unitized curtain wall element for tertiary office buildings. The façade element integrates a complete solar thermal system consisting of a solar collector, a hot water storage, a radiant panel and all the required operation components. A mock-up of the solar facade is manufactured to identify practical constructive issues. The thermal behaviour of the tank is analysed through FEM simulations and laboratory tests

    Totally percutaneous valve replacement for severe aortic regurgitation in a degenerating bioprosthesis

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    Recently, the feasibility and safety of percutaneous aortic valve replacement (PAVR) has been reported in the treatment of degenerative aortic valve stenosis in patients at high-risk for surgical aortic valve replacement (AVR).1 However, so far this therapy has been limited to patients with severe stenosis of the native valve. We report the case of a patient with severe aortic regurgitation owing to bioprosthesis dysfunction who was successfully treated by implantation of a CoreValve (CoreValve Inc, Irvine. Calif) prosthesis with a totally percutaneous approach

    A CONSCIENTIZAÇÃO DO TRABALHO INFANTIL: SOB A ÓPTICA DE UM PROJETO PETECA REALIZADO EM UMA ESCOLA MUNICIPAL

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    O presente artigo relata a história da exploração do trabalho infantil no Brasil desde a época dos colonizadores portugueses, bem como faz uma análise da legislação que regulamenta idade mínima e condições de trabalho. Ainda, visa demonstrar a possibilidade e eficácia dos instrumentos de proteção contra essa exploração, apontando a educação como mola propulsora da cultura e do desenvolvimento

    Early primary tumor response in metastatic RCC patients treated with immune checkpoint inhibitors-based combinations

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    Background: 25-30% of renal cell carcinoma presents with metastases (mRCC) at diagnosis. The activity of immune checkpoint inhibitor (ICI)-combinations on the primary tumor (PT) is debated. Patients andMethods: mRCC patients (pts) with PT who received first-line nivolumab plus ipilimumab (N/I) or pembrolizumab plus axitinib (P/A) were included. We investigated the early primary tumor response (EPTR) at the first radiological assessment. Results: 73 pts were included. The median early reduction of the PT longest diameter was 12.4% with P/A versus 6.2% with N/I (p = 0.42). We evaluated if the type of EPTR could affect the metastases response. Among pts with PT stable disease (SD), 8.3% had metastatic disease progression (PD) with P/A and 34.8% with N/I. Early PT partial response (PR) was associated with no metastatic PD with both N/I and P/A. The 2 pts with PT PD had also metastatic PD to P/A. Of the 3 PT with PD to N/I, 1 had metastatic SD and 2 PD. In the overall population, of the 94.1% without PT progression (PR+SD), 47.5% had metastatic PR, 35.6% SD, 16.9% PD. Conclusions: ICIs-combinations achieved an early PT PR in about 10-20%, without any complete responses. Only a small percentage of PT had an early PD, mainly associated with metastatic PD. However, among those PT without an early progression, metastatic PR can be achieved in approximately 50% of cases

    A highly endemic area of Echinococcus multilocularis identified through a comparative re-assessment of prevalence in the red fox (Vulpes vulpes), Alto Adige (Italy: 2019-2020)

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    Surveillance of Echinococcus multilocularis at the edge of its range is hindered by fragmented distributional patterns and low prevalence in definitive hosts. Thus, tests with adequate levels of sensitivity are especially important for discriminating between infected and non-infected areas. In this study we reassessed the prevalence of E. multilocularis at the southern border of its distribution in Province of Bolzano (Alto Adige, northeastern Alps, Italy), to improve surveillance in wildlife and provide more accurate estimates of exposure risk. We compared the diagnostic test currently implemented for surveillance based on coproscopy and multiplex PCR (CMPCR) to a real-time quantitative PCR (qPCR) in 235 fox faeces collected in 2019 and 2020. The performances of the two tests were estimated using a scraping technique (SFCT) applied to the small intestines of a subsample (n = 123) of the same foxes as the reference standard. True prevalence was calculated and the sample size required by each faecal test for the detection of the parasite was then estimated. True prevalence of E. multilocularis in foxes (14.3%) was markedly higher than reported in the last decade, which was never more than 5% from 2012 to 2018 in the same area. In addition, qPCR showed a much higher sensitivity (83%) compared to CMPCR (21%) and agreement with the reference standard was far higher for qPCR (0.816) than CMPCR (0.298) meaning that for the latter protocol, a smaller sample size would be required to detect the disease. Alto Adige should be considered a highly endemic area. Routine surveillance on definitive hosts at the edges of the E. multilocularis distribution should be applied to smaller geographic areas, and rapid, sensitive diagnostic tools using directly host faeces, such as qPCR, should be adopted
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