946 research outputs found

    Passenger car equivalent for heavy vehicles crossing turbo-roundabouts

    Get PDF
    Turbo-roundabouts represent an innovative scheme of modern roundabouts which provides a spiraling traffic flow and requires drivers to choose their direction before entering the intersection, since raised lane separators mark the lanes on the ring. The configuration of the turbo-roundabout makes that patterns of conflict at entries with one and two conflicting traffic streams can coexist. This paper presents research efforts aimed at measuring quantitatively the effect of heavy vehicles on operational conditions of a turbo-roundabout. The study starts from the initial belief that the greatest constraints to the vehicular trajectories imposed by the turbo-roundabout necessarily imply that the impact of heavy vehicles on the quality of traffic flow is more unfavorable than on other modern roundabouts. Microsimulation revealed as a useful tool when the variation of the traffic quality in turbo-roundabouts should be evaluated in presence of mixed fleets, each having different percentages of heavy vehicles; indeed, it allowed to isolate traffic conditions difficult to observe on field and replicate them to have a number of data as much as possible numerous. Entry capacity values for each entry lane of the turbo-roundabout were obtained by microsimulation, varying the percentage of heavy vehicles for entering flows. Nonlinear regression analysis of simulation data allowed to derive the behavioral parameters for heterogeneous populations of users and, ultimately, composed exclusively of heavy vehicles. The capacity functions thus obtained allowed us to determine how the passenger car equivalent (PCE) varies with the percentage of heavy vehicles and circulating flows for each entry lane of the turbo-roundabout. The results of this study indicate that there is a need to distinguish the impact of heavy vehicles when analyzing the capacity of a turbo-roundabout. When the traffic stream contains a significant number of heavy vehicles, a larger PCE effect would be expected. This effect should be accounted for in the estimation of the turbo-roundabout capacity. Lastly it should be emphasized that an important aspect of the research consists in having identified a methodology for assessing the impact of heavy vehicles on the quality of traffic flow, that can be applied to different patterns of intersection

    Usefulness of hybrid SPECT/CT for the 99mTc-HMPAO-labeled leukocyte scintigraphy in a case of cranial osteomyelitis

    Get PDF
    Cranial osteomyelitis is a potentially fatal lesion. White blood cell scanning (WBC) with 99mTc-hexamethylpropylene amine oxime (HMPAO) has proven highly sensitive and specific in the diagnosis and follow-up of patients with suspected osteomyelitis. In this report we show the usefulness of SPECT and transmission CT performed simultaneously using a hybrid imaging device for the functional anatomic mapping of soft tissue and cranial bone infections. 99mTc-HMPAO-labeled leukocytes scintigraphy was performed on an elderly diabetic man with an intracranial mass lesion and with suspected temporal bone infection. Planar scans were acquired 30 min, 4 h, and 24 h after injection. SPECT/CT was obtained 6 h after tracer injection, using a dual-head camera coupled with a low-power X-ray tube. The scintigraphic results were matched with the results of surgery and of clinical follow-up. The planar images alone were true-positives for abscess in this patient. SPECT/CT improves the accuracy of 99mTc-HMPAO scintigraphy especially in discriminating between soft-tissue and bone involvement. In fact, SPECT/CT also showed temporal bone osteomyelitis. This result indicates that SPECT/CT performed using a hybrid device can improve imaging with 99mTc-HMPAO-labeled leukocytes in patients with suspected osteomyelitis by providing accurate anatomic localization and precise definition of the extent of infection

    Effects of L-histidine on hydrogen peroxide-induced DNA damage and cytotoxicity in cultured mammalian cells.

    Get PDF
    L-Histidine markedly increased the growth- and DNA synthesis-inhibitory effects elicited by hydrogen peroxide in cultured Chinese hamster ovary cells. DNA single-strand breakage was also higher in the presence of the amino acid and, in addition, these breaks were characterized by a slower rate of repair, compared with that of the breaks generated by the oxidant alone. In the presence of L-histidine, hydrogen peroxide also produced DNA double-strand breakage, a lesion that cannot be detected in cells treated with even exceedingly high concentrations of the oxidant alone. Data reported herein suggest that the L-histidine-mediated increase of the cytotoxic response of cultured Chinese hamster ovary cells to hydrogen peroxide may be at least partially dependent on the formation of DNA double-strand break

    Botulinum toxin type A combined with neurodynamic mobilization for upper limb spasticity after stroke: a case report

    Get PDF
    Objective: The purpose of this study is to report a case in which combinatory therapy of botulinum toxin type A (BoNT-A) and neurodynamic mobilization (NM) was used as treatment for a patient with severe upper limb spasticity and pain after stroke. Clinical Features: A 76-year-old male patient had spastic muscles in the upper limb 10 months after an ischemic stroke. Intervention and Outcome: The patient underwent combined treatment with BoNT-A and NM of the upper limb in 6 monthly applications. Evaluation was performed pretreatment, 3 months after the first injection, 3 months after the second injection, and at a follow-up session 9 months after starting the treatment. The following outcomes were measured: pain by using a numeric rating scale, spasticity by the Modified Ashworth Scale for Grading Spasticity, acceptance and emotional reaction to the treatment by the Hospital Anxiety and Depression Scale, and functionality by ranges of motion. The patient improved in all outcomes after treatment, and results were maintained during the follow-up sessions. Conclusion: The combined NM and BoNT-A treatment appeared to decrease pain and improve joint ranges of motion during treatment for this patient. The patient showed decreased anxiety and depression during and after the treatment.Fil: Villafañe, Jorge Hugo. Universidad Rey Juan Carlos; EspañaFil: Silva, Guillermo Benjamin. Universidad Católica de Córdoba. Facultad de Ciencias Químicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Chiarotto, Alessandro. Universidad Rey Juan Carlos; EspañaFil: Ragusa, Orazio L. F.. No especifíca

    Isolation and preliminary characterization of a Chinese hamster ovary cell line with high-degree resistance to hydrogen peroxide.

    Get PDF
    We have isolated and conducted preliminary characterization of a cell line derived from the Chinese hamster ovary cell line AA8, which we have designated AG8 and which is highly resistant to the cytotoxic effects of H2O2 (approximately 17-fold when the H2O2 treatment was at 37 degrees; approximately 11-fold when the H2O2 treatment was at 4 degrees). AG8 cells were moderately (but significantly; P Be+) fast neutrons. As regards their biochemical status, AG8 and AA8 cells contain similar non-protein sulfhydryl levels per milligram of protein. Catalase activity (assessed by both spectrophotometry and polarography) was significantly higher in AG8 than in AA8 cells irrespective of whether enzyme activity was expressed per 10(6) cells (approximately 3.6-fold increase) or per milligram of protein (approximately 1.6-fold increase). AG8 cells also exhibited significantly greater glutathione reductase activity than wild-type cells when the data were expressed per 10(6) cells (approximately 2.9-fold) or per milligram of protein (approximately 1.3-fold). Glutathione peroxidase activity was immeasurably low in both cell lines. The susceptibility of the two cell lines to H2O2-mediated generation of DNA single-strand breaks (as measured by alkaline elution) indicated a slightly (approximately 1.5-fold) decreased yield in the resistant AG8 cell line. The two cell lines repaired these breaks with similar kinetics. In contrast, no measurable induction of DNA double-strand breaks (as measured by pulsed-field gel electrophoresis) was apparent in either cell line after survival-curve range concentrations of H2O2. On the basis of these data, it appears that the AG8 phenotype involves two previously identified resistance mechanisms, namely an adaptive component that may or may not involve increased antioxidant capacity, and a second component that does involve increased antioxidant (primarily catalase) capacity

    Second Opinion System for Intraoral Lesions

    Get PDF
    In this paper we present the prototype of a teledentistry system to perform the remote diagnosis of oral diseases. It makes use of a particular device called intra-oral (or dental) camera properly designed to shoot video and take pictures of the inner part of the mouth. The intra-oral cameras can be connected via USB to a common PC and they are very cheap, unlike the intra-oral photography kit for DSLR cameras. Usually this kind of devices are used in dentistry studies for local visualization by means of specialized software. The novelty of our system is that the real-time video produced by this device is canalized into a video streming by means of VideoLan client/server (VLC) and pictures can be sent by a current File Tranfer Protocol (FTP) service to realize a Second Opinion Syste

    Comparing treatment options for chronic inflammatory neuropathies and choosing the right treatment plan

    Get PDF
    Introduction: Chronic inflammatory neuropathies are disorders caused by an immune response to peripheral nerve. They include chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), multifocal motor neuropathy (MMN) and neuropathy associated with anti-MAG IgM monoclonal gammopathy and other less frequent neuropathies. Several immune therapies have been proven to be effective in these neuropathies even if the best therapeutic option is still unsettled. Areas covered: The authors reviewed the literature to compare the efficacy and safety of currently used immune therapies in these neuropathies. The authors also analyzed the effect of other immune suppressive agents and of biological agents including rituximab, eculizumab, natalizumab, alemtuzumab and fingolimod that were found effective in other autoimmune diseases. Expert commentary: Despite the reported efficacy of a number of new immune therapies in some patients with immune mediated neuropathies, their efficacy has not been so far confirmed in randomized controlled studies. High-dose intravenous immunoglobulin (IVIg) (and subcutaneous immunoglobulin [SCIg] for maintenance treatment), steroids and plasma exchange remain the only therapy of proven efficacy in CIDP, IVIg in MMN and, with certain limits, rituximab and, occasionally plasma exchange in neuropathy associated with anti-MAG antibodies. New biological agents are also on the horizon but their efficacy needs to be proved in controlled studies

    A triple GEM gamma camera for medical application

    Get PDF
    Abstract A Gamma Camera for medical applications 10 Ă— 10 cm 2 has been built using a triple GEM chamber prototype. The photon converters placed in front of the three GEM foils, has been realized with different technologies. The chamber, High Voltage supplied with a new active divider made in Frascati, is readout through 64 pads, 1 mm 2 wide, organized in a row of 8 cm long, with LHCb ASDQ chip. This Gamma Camera can be used both for X-ray movie and PET-SPECT imaging; this chamber prototype is placed in a scanner system, creating images of 8 Ă— 8 cm 2 . Several measurements have been performed using phantom and radioactive sources of Tc 99 m ( 140 keV ) and Na 22 ( 511 keV ) . Results on spatial resolution and image reconstruction are presented
    • …
    corecore