2,154 research outputs found

    Exploration of cortical effect of PAS

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    Context: Transcranial Magnetic stimulation (TMS) is a non-invasive stimulation technique of the brain, which allows the investigation of the neuronal plasticity and cortical circuits in humans. This method is based on the generation of an impulse by using an electromagnetic induction (1). Paired associative stimulation (PAS) is a non-invasive technique used to induce and to study the plasticity in the human motor cortex. Essentially, it is the repeated pairing of a peripheral stimulation with a cortical stimulation (2). PAS induces an LTP-like effect with an inter-stimulus interval of 25ms. The latencies of afferent signals from the median nerve stimulation at the wrist to reach the motor cortex (M1) after 20-25ms in order to produce synchronous pre- and postsynaptic activation (3). This change of excitability in the motor cortex induced by PAS is quantified by recording motor evoked potentials (MEP) before and after the intervention. Another way to study alterations in the motor cortex with TMS is to record the long interval intra-cortical inhibition (LICI) before and after PAS. It is very important to know that the PAS response is characterized by a high inter/intra-subject variability (4). This variability could be partially explained by the fact that every subject has a different level of excitability before the PAS. So, a reason to investigate the effect of PAS on MEP and LICI is to understand if PAS could be a method to set every subject at the same level of excitability before studying his plasticity in order to have more comparable results. Objectives: This study is part of a larger project that investigates potential interactions between different techniques exploring focal dystonia in patients with the Complex Regional Pain Syndrome (CRPS). This study explores and compares two protocols of PAS, the conventional low frequency PAS (0.2 Hz) with a high frequency (5Hz) PAS. Method: In our study, we will investigate the plasticity of the motor cortex and inhibition in 15 healthy subjects. The PAS protocol is a 2 stimuli sequence separated by a specific interval (25ms). We will deliver an electric stimulus on the median nerve followed by a TMS pulse at the level of the motor cortex with an 8-shaped magnetic coil. we record the MEP from the abductor digiti minimi muscle (ADM), Dorsal interossei of the hand (FDI). The paired-pulse TMS paradigm (ppTMS) resides in the combination of a subthreshold conditioning stimulus with a suprathreshold test stimulus at different intervals. LICI will be recorded by ppTMS using 100ms as interval with two suprathreshold stimulus. Conclusions: Both 5Hz and 0.2Hz PAS protocols have comparable effects on motor cortex, about ¾ of the subjects show lpong-term potentiation. There were no side effects, but some subjects found 5Hz unpleasant

    EXPERIMENTAL ANALYSIS OF A HEAT PUMP ASSISTED RECUPERATIVE AIR DEHUMIDIFIER

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    This paper describes the experimental analysis of a heat pump assisted recuperative air dehumidifier. The system consisted of an air-to-air vapor compression heat pump, coupled to the air ducting. Dehumidification was generated by reduction of the air temperature through the evaporator below the dew point, and thus promoting the condensation of the water vapor. Moist air was then warmed up in the condenser, resulting in a lowtemperature low-humidity air stream. Low energy consumption values are achieved in such systems as the latent heat of the water vapor acts as the heat pump own heat source. Occasionally, the compressor heat is also recoverable. The innovative feature of the present analysis was the introduction of an air-to-air plate recuperator, to further promote dehumidification, yet at the expense of greater compressor energy consumption. An experimental apparatus was constructed to perform comparative tests of the dehumidifier operating with and without the recuperator. A closed air circuit was employed, with the air mass flow rate as the controlling parameter of the experiment. Tests were also carried out with an open circuit

    Fat area and lipid droplet morphology of porcine oocytes during in vitro maturation with trans-10, cis-12 conjugated linoleic acid and forskolin

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    Lipid droplets (LD) in porcine oocytes form a dark mass reaching almost all cytoplasm. Herein we investigated changes in fat areas, cytoplasmic tone and LD morphology during in vitro maturation (IVM) of porcine oocytes cultured with 100mM trans-10, cis-12 conjugated linoleic acid (t10,c12 CLA) or 10mM forskolin at different time periods. Four groups were constituted: control, excipient, t10,c12 CLA and forskolin, with drugs being supplemented during 44 to 48h and the initial 22 to 24h in Experiments 1 and 2, respectively. In Experiment 3, forskolin was supplemented for the first 2 h. Matured oocytes were inseminated with frozen-thawed boar semen and cleavage rate recorded. Before and during IVM, samples of oocytes were evaluated for LD, total and fat areas and fat gray value or for meiotic progression. Results showed that forskolin supplementation during 44 to 48 h or 22 to 24 h inhibits oocyte maturation (exp. 1: forskolin = 5.1±8.0%, control = 72.6±5.0%; exp. 2: forskolin =24.3±7.4%, control =71.6±5.6%) and cleavage (exp. 1: forskolin=0.0±0.0%, control=55.4±4.1%; exp. 2: forskolin=8.3±3.3%, control=54.5±3.0%). Forskolin also reduced oocyte and fat areas. In Experiment 3, forskolin negative effect on oocyte maturation and cleavage disappeared, although minor (P<0.03) LD and oocyte fat areas were identified at 22 to 24 h of IVM. Oocytes supplemented with t10,c12 CLA during 44 to 48h presented a lighter (P<0.04) colour tone cytoplasm than those of control and forskolin. In conclusion, t10,c12 CLA and forskolin were capable of modifying the distribution and morphology of cytoplasmic LD during porcine oocyte maturation, thus reducing its lipid content in a time-dependent manner

    BioRePortAP, an electronic clinical record coupled with a database : an example of its use in a single

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    Aims: To evaluate the efficacy and safety of the treatment of psoriatic arthritis (PsA) patients with tumor necrosis factor (TNF) antagonists in the Rheumatology Department of Hospital de Santa Maria using the BioRePortAP. Methods: The Portuguese Society of Rheumatology (SPR) developed an electronic medical chart coupled with a database for the follow up of PsA patients, the BioRePortAP, which was launched in May 2009. This evaluation was based on all the PsA patients that were on active treatment with TNF antagonists in September 2009 and were registered in the BioRePortAP. All the previous data on these patients were introduced in BioRePortAP using the prospective paper based follow up protocol that this Department was using since 1999. Only patients with more than 9 months of treatment were analyzed. Results: Forty-two patients with PsA, actively treated with anti-TNF agents in September 2009, for at least 9 months, were analyzed in BioRePortAP. Twenty-three patients were male (55%) and nineteen were female (45%). The average age of these patients was 49.8±10.9 years old, the average disease duration was of 10.7±5.6 years and the mean duration of biological therapy was of 37.8±27.8 months. For the 81% of patients with peripheral joint disease there was a mean reduction of more than 80% in the swollen and tender joint counts, and almost 50% in the health assessment questionnaire (HAQ) value. In the 19% of the patients with axial involvement the reduction of BASDAI and BASFI was not statistically significative. On top of that, PASI score suffered a reduction of 64%. Fourteen patients (33.3%) had to switch their TNF antagonist treatment. 58.8% of the switches were due to adverse effects and 41.2% due to therapy failure. Regarding the 56 adverse reactions registered, only one was a severe reaction. The remaining adverse reactions were not severe and 67% of them were due to infections. Discussion: The results of this first report of the use of the BioRePortAP in clinical practice confirm the efficacy and safety of TNF antagonist treatment in PsA. The results shown here elucidate the potential applications of BioRePortAP as a tool for efficacy and safety assessment of PsA patients treated with biotechnological drugs

    Impact of a Virtual Reality-Based Simulation on Empathy and Attitudes Toward Schizophrenia

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    Virtual Reality (VR) has been identified as one of the most promising resources for developing empathy towards stigmatized groups as it allows individuals to experience a situation close to reality from another person’s perspective. This quasi-experimental study aimed to examine the impact on empathy, knowledge, and attitudes towards people with schizophrenia of a VR simulation that reproduces the experience of psychotic symptoms while performing a cognitive task compared with watching a 2D video and, thus, how these experiences could reduce stigma towards people diagnosed with schizophrenia. The sample comprised of 102 higher education health students, distributed by the experimental and control groups. The impact of the program was measured by completing multiple questionnaires on levels of empathy, attitudes, and mental health knowledge. Both methods (VR and 2D video) were, to a certain extent, effective. However, VR was more effective at eliciting attitudes and knowledge change compared to the control group. These findings suggest that not only VR but also 2D videos could be interesting strategies to enhance empathy and improve attitudes towards people with schizophrenia in higher education health students

    Lesão de Dieulafoy: Papel do Mapeamento por Ecoendoscopia

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    info:eu-repo/semantics/publishedVersio

    On the far-infrared metallicity diagnostics: applications to high-redshift galaxies

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    In an earlier paper we modeled the far-infrared emission from a star-forming galaxy using the photoionisation code CLOUDY and presented metallicity sensitive diagnostics based on far-infrared fine structure line ratios. Here, we focus on the applicability of the [OIII]88/[NII]122 microns line ratio as a gas phase metallicity indicator in high redshift submillimetre luminous galaxies. The [OIII]88/[NII]122 microns ratio is strongly dependent on the ionization parameter (which is related to the total number of ionizing photons) as well as the gas electron density. We demonstrate how the ratio of 88/$122 continuum flux measurements can provide a reasonable estimate of the ionization parameter while the availability of the [NII]205 microns line can constrain the electron density. Using the [OIII]88/[NII]122 microns line ratios from a sample of nearby normal and star-forming galaxies we measure their gas phase metallicities and find that their mass metallicity relation is consistent with the one derived using optical emission lines. Using new, previously unpublished, Herschel spectroscopic observations of key far-infrared fine structure lines of the z~3 galaxy HLSW-01 and additional published measurements of far-infrared fine structure lines of high-z submillimetre luminous galaxies we derive gas phase metallicities using their [OIII]88/[NII]122 microns line ratio. We find that the metallicities of these z~3 submm luminous galaxies are consistent with solar metallicities and that they appear to follow the mass-metallicity relation expected for z~3 systems.Comment: 10 pages, 7 figures, MNRAS in pres

    A influência da presença de ferro endógeno na remediação de diesel via reagente de Fenton modificado.

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    Este trabalho avaliou a eficiência catalítica do ferro endógeno na reação de Fenton para a remediação de diferentes solos tropicais contaminados com o óleo diesel com diferentes teores das seguintes formas de ferro endógenos: amorfo, pedogenético, biodisponível e total. Em 70% de degradação do óleo diesel. Íons férricos encontrados, naturalmente, nos solos brasileiros também catalisam a decomposição do H2O2 para geração de radicais hidroxilas. Contudo, foi observado que a taxa de remediação é dependente das formas de ferro encontradas nos solos
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