Body machine interfaces (BMIs) are used by people with severe motor disabilities to control external devices, but they also offer the opportunity to focus on rehabilitative goals. In this study we ...introduced in a clinical setting a BMI that was integrated by the therapists in the rehabilitative treatments of 2 spinal cord injured (SCI) subjects for 5 weeks. The BMI mapped the user's residual upper body mobility onto the two coordinates of a cursor on a screen. By controlling the cursor, the user engaged in playing computer games. The BMI allowed the mapping between body and cursor spaces to be modified, gradually challenging the user to exercise more impaired movements. With this approach, we were able to change our subjects' behavior, who initially used almost exclusively their proximal upper body-shoulders and arms - for using the BMI. By the end of training, cursor control was shifted toward more distal body regions - forearms instead of upper arms - with an increase of mobility and strength of all the degrees of freedom involved in the control. The clinical tests and the electromyographic signals from the main muscles of the upper body confirmed the positive effect of the training. Encouraging the subjects to explore different and sometimes unusual movement combinations was beneficial for recovering distal arm functions and for increasing their overall mobility.
This paper discusses the laboratory testing of wall-like reinforced concrete (RC) columns externally confined with glass fiber reinforced polymer (GFRP) laminates and subjected to pure axial load. ...Specimens were characterized by an overall length of 3.05 m (10 ft), cross-sectional dimensions of 356 by 1,041 mm (14 by 41 in). Three specimens were tested: one was unstrengthened (benchmark) and two were confined with GFRP laminates. Two different confining reinforcement ratios were considered. The experimental investigation aimed at characterizing: the confinement contribution in terms of axial strength and prevention of instability of longitudinal bars, and the sensitivity of any enhancement in performance to the confining reinforcement ratio. The experimental axial stress – axial strain curves are also discussed.
Abstract Injections of the excitatory amino acid l -glutamate ( l -glu) into the rostral ventrolateral medulla (RVLM) directly activate the sympathetic nervous system and increase mean arterial ...pressure (MAP). A previous study showed that lesions of the anteroventral third ventricle region in the forebrain reduced the pressor response to l -glu into the RVLM. In the present study we investigated the effects produced by injections of atropine (cholinergic antagonist) into the lateral ventricle (LV) on the pressor responses produced by l -glu into the RVLM. Male Holtzman rats (280–320 g, n = 5 to 12/group) with stainless steel cannulas implanted into the RVLM, LV or 4th ventricle (4th V) were used. MAP and heart rate (HR) were recorded in unanesthetized rats. After saline into the LV, injections of l -glu (5 nmol/100 nl) into the RVLM increased MAP (51 ± 4 mm Hg) without changes in HR. Atropine (4 nmol/1 μl) injected into the LV reduced the pressor responses to l -glu into the RVLM (36 ± 5 mm Hg). However, atropine at the same dose into the 4th V or directly into the RVLM did not modify the pressor responses to l -glu into the RVLM (45 ± 2 and 49 ± 4 mm Hg, respectively, vs. control: 50 ± 4 mm Hg). Central cholinergic blockade did not affect baro and chemoreflex nor the basal MAP and HR. The results suggest that cholinergic mechanisms probably from forebrain facilitate or modulate the pressor responses to l -glu into the RVLM. The mechanism is activated by acetylcholine in the forebrain, however, the neurotransmitter released in the RVLM to facilitate the effects of glutamate is not acetylcholine.
The aim of present study is to investigate different methodologies to retrofit photovoltaic modules (PV), in order to ensure a good cooling effect by adding a thermal plate in the back side of the PV ...panel to collect heat, thus obtaining a thermal photovoltaic module (PVT). The most promising perspective of this technology is to couple it with a heat pump, in order to obtain a photovoltaic thermal solar-assisted heat pump (PVT-SAHP) system. This work proposes an investigation of three different solutions to retrofit commercial PV panels. A thermography analyses has been performed in order to verify the cooling effect on the PV module. Results show that retrofitting of existing photovoltaic panels represents an interesting approach in order to employ very simple solutions to increase the overall efficiency of PV system, especially by coupling it with a heat pump. Finally, in order to study the effective potential of this technology, three different system configurations have been compared in terms of primary energy efficiency, namely a photovoltaic solar assisted heat pump (PVT-SAHP), a solar assisted heat pump (SAHP) and an air-to-water heat pump with a separate set of photovoltaic panels.
We present the first X-ray detection of the very young pulsar PSR J1357-6429 (characteristic age of 7.3 kyr) using data from the XMM-Newton and Chandra satellites. We find that the spectrum is well ...described by a power-law plus blackbody model, with photon index $\Gamma=1.4$ and blackbody temperature $k_{\rm B}T=160$ eV. For the estimated distance of 2.5 kpc, this corresponds to a 2–10 keV luminosity of ~1.2 $\times$ 1032 erg s-1, thus the fraction of the spin-down energy channeled by PSR J1357-6429 into X-ray emission is one of the lowest observed. The Chandra data confirm the positional coincidence with the radio pulsar and allow to set an upper limit of 3 $\times$ 1031 erg s-1 on the 2–10 keV luminosity of a compact pulsar wind nebula. We do not detect any pulsed emission from the source and determine an upper limit of 30% for the modulation amplitude of the X-ray emission at the radio frequency of the pulsar.
We present the results of a image230 ks long X-ray observation of the relativistic double-pulsar system PSR J0737-3039 obtained with the XMM- Newton satellite in 2006 October. We confirm the ...detection in X-rays of pulsed emission from PSR J0737-3039A (PSR A), mostly ascribed to a soft nonthermal power-law component with a 0.2-3 keV luminosity of image erg s super(-1) (assuming a distance of 500 pc). For the first time, pulsed X-ray emission from PSR J0737-3039B (PSR B) is also detected in part of the orbit. This emission, consistent with thermal radiation with temperature image eV and a bolometric luminosity of image10 super(32) erg s super(-1), is likely powered by heating of PSR B's surface caused by PSR A's wind. A hotter (image130 eV) and fainter (image erg s super(-1)) thermal component, probably originating from backfalling particles heating polar caps of either PSR A or PSR B, is also required by the data. No signs of X-ray emission from a bow shock between PSR A's wind and the interstellar medium or PSR B's magnetosphere are present. The upper limit on the luminosity of such a shock component (image10 super(29) erg s super(-1)) constrains the wind magnetization parameter image of PSR A to values greater than 1.
The incidence of postoperative nausea and vomiting (PONV) is high after laparoscopic surgery. A number of drugs have been used for prevention; in some studies a single dexamethasone dose before ...induction of anaesthesia has been effective.
To test the effectiveness of this therapy, we recruited 80 patients in a double-blind placebo-controlled study (dexamethasone 8 mg or placebo) scheduled for laparoscopic cholecystectomy. We measured nausea, vomiting, postoperative pain and length of stay.
Patients who received preoperative dexamethasone had a reduction of PONV, but experienced the same degree of postoperative pain and remained in the hospital for the same duration. No apparent side effects were observed.
Although only a small number of patients were tested, we confirm the efficacy of dexamethasone therapy for reduction of PONV. We suggest routine use of a single dose of dexamethasone for the prevention of PONV in laparoscopic cholecystectomy.
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