1,218 research outputs found

    Schwannoma vestibular (neurinoma do acústico) imitando desordens temporomandibulares: um relato de caso

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    Aproximadamente 6 a 16% dos pacientes com sintomas de neuralgia trigeminal apresentam tumores intracranianos, sendo mais comum o schwannoma vestibular (neurinoma do acústico). Alguns sintomas relatados pelos pacientes são perda da audição, zumbido, dores de cabeça, vertigens e distúrbios trigeminais. Uma resposta muscular aumentada na musculatura associada da cabeça e do pescoço também pode ser observada, o que pode mimetizar sinais e sintomas de desordens temporomandibulares. Nestes casos é de grande valia o uso de imagem de ressonância magnética (IRM) para detecção de tumores. É importante, também, a diferenciação de dores miofasciais e neurálgicas, pois ambas podem apresentar características semelhantes, mas com origens e tratamentos diferentes. O objetivo desse trabalho foi demonstrar através de relato de caso clínico a associação entre sintomas de neuralgia trigeminal, tumores intracranianos e disfunção temporomandibular.Approximately 6 to 16% of patients with trigeminal neuralgia symptoms present intracranial tumors, the most common being the vestibular schwannoma (acoustic neuroma). Some symptoms reported by patients include hearing loss, tinnitus, headaches, vertigo and trigeminal disturbances. An increased muscle response in the surrounding head and neck musculature may also be observed, which mimics signs and symptoms of temporomandibular disorders. In these cases, magnetic resonance imaging (MRI) has proved to be a useful tool in tumor diagnosis. The differential diagnosis between myofascial and neuralgic pain is important, as both may present similar characteristics, while being of different origin, and demanding special treatment approaches. The purpose of this paper is to demonstrate the relationship among trigeminal neuralgia symptoms, intracranial tumors and temporomandibular dysfunction by presenting a clinical case

    A BGK model for reactive mixtures of polyatomic gases with continuous internal energy

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    Versão dos autores para esta publicação.In this paper we derive a BGK relaxation model for a mixture of polyatomic gases with a continuous structure of internal energies. The emphasis of the paper is on the case of a quaternary mixture undergoing a reversible chemically reaction of bimolecular type. For such a mixture we prove an H-theorem and characterize the equilibrium solutions with related mass action law of chemical kinetics. Further, a Chapman-Enskog asymptotic analysis is performed in view of computing the first-order non-equilibrium corrections to the distribution functions and investigating the transport properties of the reactive mixture. The chemical reaction rate is explicitly derived at the first-order and the balance equations for the constituent number densities are derived at the Euler level.The paper is partially supported by the Italian National Group GNFM of INdAM and by the Portuguese Funds FCT Project UID/MAT/00013/2013. One of the Authors (AJS) thanks the Italian institution for the financial support given in her visiting professor program in Italy.info:eu-repo/semantics/publishedVersio

    Experimental and numerical analysis of a CO2 dual-source heat pump with PVT evaporators for residential heating applications

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    Multi-source energy systems are a promising solution to lower the environmental impact of the heating and cooling sector and enhance the exploitation of renewable energy sources. In this context, dual-source solar-assisted heat pumps exploit solar energy and air as the low-temperature heat sources. However, the efficiency of solar-based systems is strictly related to weather conditions, location, and time. Therefore, there is a need for accurate models to be used in dynamic simulations of these systems and perform detailed performance analyses and study the involved energy flows. This paper presents an experimental and numerical investigation of a direct-expansion solar-assisted heat pump (DX-SAHP) operating with CO2 as the refrigerant. The heat pump prototype can work with an air-finned coil heat exchanger or photovoltaic-thermal (PVT) solar collectors as the evaporator. The solar-mode configuration allows the exploitation of the heat from solar radiation to evaporate the refrigerant and to improve the photovoltaic electricity production due to the cooling of the cells up to 8%. A numerical heat pump model, integrated with novel gas-cooler and PVT collectors models, has been developed and implemented as a TRNSYS type for dynamic simulations of the system. The model has been validated with continuous measurements during the heat pump operation in solar and air modes. The proposed model can be used for performing seasonal simulations of a heat pump operating with a transcritical CO2 cycle. Moreover, the outcomes of the analysis show how the configuration of a CO2 heat pump with a direct-expansion air-finned coil heat exchanger or PVT can be used to enhance the performance of the heat pump and increase the electrical efficiency of the photovoltaic cells

    The strong and the hungry: Bias in capture methods for mountain hares (Lepus timidus).

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    Estimating density, age and sex structure of wild populations is a key objective in wildlife management. Live trapping is frequently used to collect data on populations of small and medium-sized mammals. Ideally, sampling mammal populations by live capturing of individuals provides a random and representative sample of the target population. Trapping data may, however, be biased. We used live-capture data from mountain hares Lepus timidus in Scotland to assess sampling bias between two different capture methods.Wecaptured hares using baited cage traps and long nets on five study areas in the Scottish Highlands. After controlling for the effects of body size, individuals caught in traps were lighter than individuals caught using long nets, suggesting that the body condition of hares differed between the capture methods. This tendency may reflect an increased risk-taking of individuals in poorer body condition and less aversion to entering traps in order to benefit from eating bait. Overall, we caught more adult hares than juveniles and more female hares than males. Our results show that estimates of density and population structure of mountain hares using livecapture data could be affected by the capture method used. We suggest that live-capture studies employ more than one capture method and test for heterogeneity in capture probability to minimise potential bias and achieve reliable estimates of population parameters

    Role of endoscopy in lateral skull base approaches to the petrous apex

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    Objective: The aim of this article is to study the role and advantages of combined microscopic/endoscopic procedures or exclusive endoscopic approaches in the treatment of petrous apex pathologies. Methods: The study was designed as a retrospective case series analysis. We included patients affected by pathologies of the petrous apex, who underwent microscopic/endoscopic-assisted or exclusive endoscopic procedures. Patient and pathology characteristics and surgical data (focusing on the involvement of the internal carotid artery (ICA) and facial nerve by the disease) were collected. Residual disease, detected through the endoscopic check, and the feasibility of endoscopic residual tumor removal were also evaluated. Finally, facial nerve and hearing functions were assessed pre- and postoperatively. Results: The records of 75 patients undergoing lateral skull base surgery for petrous apex lesions, from May 2009 to March 2019, were collected. In 17 out of 75 patients, an exclusive endoscopic procedure was possible. The remaining 58 patients underwent a combined microscopic/endoscopic approach. In 15 cases, residual disease was found and removed endoscopically at the end of the microscopic procedure; in eight cases, the residual disease was medial and/or inferior to the horizontal segment of the ICA, while in two cases, it was located in the fundus of the internal auditory canal. In five cases, it involved the labyrinthine segment of the facial nerve. Conclusion: Petrous apex surgery remains a traditional microscopic-based surgery, but the recent advent of endoscopic surgery has permitted an improvement in radicality minimizing the manipulation of neurovascular structures

    Propagation of piper hispidum through leaf cuttings.

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    Made available in DSpace on 2018-10-11T00:33:56Z (GMT). No. of bitstreams: 1 2018IJDRPiperhispidum.pdf: 353394 bytes, checksum: 7cb89d851e5614e7d10c0e28b5a9d2a0 (MD5) Previous issue date: 2018-10-10bitstream/item/184171/1/2018-IJDR-Piper-hispidum.pd

    Tanaka Theorem for Inelastic Maxwell Models

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    We show that the Euclidean Wasserstein distance is contractive for inelastic homogeneous Boltzmann kinetic equations in the Maxwellian approximation and its associated Kac-like caricature. This property is as a generalization of the Tanaka theorem to inelastic interactions. Consequences are drawn on the asymptotic behavior of solutions in terms only of the Euclidean Wasserstein distance
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