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Current switch bolt inspection on rail systems is a labor intensive and sometimes unreliable approach to maintaining the switch integrity. Recent rail accidents in the United Kingdom (Potters Bar in 2002 and Grayrigg in 2007) underscore the need for routine inspections of the switch mechanisms. From the Grayrigg report of 23 February 2007 the main causes of the accident were found to be the loosening and, as a result, the initiation and growth of cracks, and, eventually, rupture of the bolts of the switch bars, especially the one maintaining the switch rails at a correct distance apart. Such findings also resulted from the 2002 crash report but unfortunately frequent visual inspections were not forthcoming. In this paper, an effective method for monitoring the loosening of the switch bolts is described. As the loosening of the bolts further causes the crack formation in the bolted joints, it seems valid to say that the early detection of loosening of bolted joints in railroad switches will be of great importance in eliminating the need for frequent visual inspection by totally automating inspection of the switches’ mechanical condition. The first part of the present paper focuses on the use of smart materials and structures for the health monitoring of bolted joints in railroad switches. It is shown that using the piezoelectric transducers and the impedance-based structural health monitoring technique, the loosening of the bolted joints are detectable. The accuracy in loosening detection is as high as 25 ft-lbs which corresponds to merely 1/10th of a bolt turn. Being able to detect the loosening of the bolted joints in railroad switches, the concept of self-healing bolted joints is applied in the next part in order to automatically retighten the loosened bolts to their prescribed functional conditions.Copyright © 2009 by ASME

Two recent analyses found that exposure to protease inhibitors (PIs) in the context of antiretroviral (ARV) therapy increased the risk for distal sensory polyneuropathy (DSPN) in subjects with human immunodeficiency virus (HIV) infection. These findings were supported by an in vitro model in which PI exposure produced neurite retraction and process loss in dorsal root ganglion sensory neurons. Confirmation of peripheral nerve toxicity with PIs could substantially limit their long-term use in highly active ARV therapy.We evaluated current and past exposure to PIs as a risk factor for DSPN in 1,159 HIV-infected individuals enrolled in a large, prospective, observational, multicenter study. Signs of DSPN were ascertained by neurological examination. Subjects were grouped into categories according to past and current exposure to any ARV and to PIs. We included disease indicators such as nadir CD4, plasma viral load, and duration of HIV infection, as well as advancing age and exposure to dideoxynucleoside ARVs in multivariate models.In univariate analyses, both past and current PI exposure significantly increased the risk for DSPN. However, after adjusting for previously validated concomitant risk factors in multivariate models, none of the PI exposure groups was more likely to have DSPN than ARV naive subjects. A secondary evaluation of duration of PI use and exposure to individual PI drugs was similarly nonsignificant in multivariate models, except for small effects of amprenavir and lopinavir.Evaluation of concomitant risks for HIV DSPN suggests that the independent risk attributable to PIs, if any, is small. This risk must be weighed against the important role of PIs in modern ARV therapy regimens.

International e-Miage International (IEM) is a program for Miage distant teaching. This Information System Engineering curriculum (to a professional end) now gathers 20 national sites which deliver fdegrees recognized by 22 universities. The IME consortium, issued from the “French Digital Campuses” proposals, regroups 18 universities. What IME program aims at is offering an e-learning version of the Miage curriculum for working computer scientists in continue training, students unable to attend face-to-face training and foreign students.

Background : Patients with idiopathic dilated cardiomyopathy (DCM) receiving an ICD often improve their left ventricular dysfunction in the year following implantation due to reverse remodelling and/or optimization of concomitant drug therapy. We examined whether this improvement impacts the benefit of ICD in terms of appropriate therapy. Methods : The study comprised 93 consecutive DCM patients with LVEF 200 bpm or Results : Overall the mean LVEF increased by 7.2 % from 24.6±7% at baseline to 31.8±12% at revaluation. Two patterns were observed: 23 patients had a >14% LVEF increase (group 1) whereas 70 others had an increase Conclusions : In DCM, rhythmic risk is dynamic and inversely related to the improvement in LVEF. Reverse remodelling under optimal therapy is associated with a late favourable outcome, but 17% of these patients however benefit from ICD therapy in the early period.

The aim of the current study was to develop and validate demographically adjusted normative standards for the HIV Dementia Scale (HDS). Given the association between demographic variables and the HDS summary score, demographically adjusted normative standards may enhance the classification accuracy of the HDS. Demographically adjusted normative standards were derived from a sample of 182 seronegative healthy participants and were subsequently applied to a sample of 135 HIV-1 seropositive individuals with multidisciplinary case conference diagnoses of HIV-1-associated neurocognitive disorders (e.g., HIV-1-associated dementia and minor-cognitive/motor disorder) in proportions consistent with published epidemiologic reports. In the normative sample, age and education (and their interaction) emerged as the only demographic factors significantly associated with the HDS. In comparison to the traditional HDS cut score (raw score totalor=10), use of the demographically adjusted normative standards significantly improved the sensitivity (from 17.2% to 70.7%, respectively) and overall classification accuracy (increasing the odds ratio from 3 to approximately 6) of the HDS for identifying participants with HIV-1-associated neurocognitive disorders. The application of demographically adjusted normative standards on the HDS improves the clinical applicability and accuracy of this cognitive screening measure in the detection of HIV-1-associated neurocognitive disorders.

The main objective of this study was to investigate the association between human CSF leptin levels and neuropsychological (NP) performance in the setting of HIV infection. We hypothesized that human CSF leptin levels positively correlate with NP performance. Leptin is an adipocyte-derived hormone that influences brain development and function, particularly learning and memory, in the mouse model. The extent to which leptin contributes to neurocognitive functioning in humans is less clear. A cross-sectional evaluation of CSF leptin and NP performance was performed. Leptin levels in CSF and serum samples from 59 HIV-positive men were measured by ELISA. Comprehensive, standardized NP testing was used to determine impairment status in global and specific domains. Lower CSF leptin levels and reduced leptin uptake into the central nervous system (CNS) correlated with impaired learning and memory performance in both univariate and multivariate analyses. In multivariate analyses, lower CSF leptin levels and reduced CNS leptin uptake were associated with worse NP performance in learning and memory, adjusting for CD4 nadir, antiretroviral treatment exposure, and HIV RNA levels in CSF. Low CSF leptin levels are associated with poorer performance in learning and memory among HIV-infected men adjusting for usual predictors of HIV-associated neurocognitive impairment. This association is consistent with prior in vitro and animal data suggesting leptin has a trophic or facilitatory role in the hippocampus, above and beyond its role in hypothalamic regulation.

Valproic acid (VPA) reduces latent human immunodeficiency virus (HIV) reservoirs by activating resting CD4+ cells. This retrospective case-control study (n = 30) examined effects of VPA on markers of HIV progression. VPA was not associated with changes in cerebrospinal fluid viral loads (VL), plasma VL, or neuropsychological performance. VPA patients had a trend towards lower CD4+ cells (P = .08) at follow-up. Concurrent antiretrovirals did not alter these relationships. VPA does not induce viremia or promote disease progression and may be safe for clinical intervention.

Available on : http://oatao.univ-toulouse.fr/776/2/Ansart_776.pdf; International audience; In this study, the formation and characterization of conversion coatings modified by a sol-gel TiO2 deposit were investigated as a way to develop a new photocatalyst for water and air depollution. The conversion coating, characterised by strong interfacial adhesion, high roughness and high surface area facilitates the sol-gel deposition of titania and enhances its adhesion to the substrate. The conversion treatment is carried out in an acid solution. Observation by Scanning Electron Microscopy (SEM) reveals a rough surface with pores and cavities. According to SIMS measurements, the thickness of the initial conversion layer is evaluated at about 1.5 μm. On this pre-functionalised support, the titanium dioxide was deposited by the sol-gel method. The roughness measurements coupled with SIMS analysis allowed a precise evaluation of the surface state of the final layers. The coating consists of two layers: a TiO2 outer layer and an inner layer containing iron chromium oxides. Characterization by X-ray diffraction (XRD) showed the existence of the TiO2 anatase structure as the main compound.

CCR2 is a minor coreceptor for human immune deficiency virus-1 (HIV-1) and its impact on HIV-1-related neuropsychological impairment (NPI) remains unknown. We studied the impact of CCR2-V64I polymorphisms on the development of NPI in 121 HIV-1 patients. The CCR2-64-I allele was associated with rate of progression to NPI when measured from the first study visit (Log Rank p=0.01) or from the estimated time of seroconversion (p=0.02). CCR2-V64I was not associated with plasma or CSF HIV-1 RNA load, suggesting that the impact of CCR2 on neuropathogenesis may involve alterations in inflammatory responses within the CNS rather than a direct impact on viral entry or replication.

The goal of this study was to examine a large, varied occupational French cohort for possible relationships between various dimensions of occupational stress, on the one hand, and the occupational status and socio-demographic characteristics of workers on the other.Data was taken from the first, cross-sectional phase of the VISAT study (aging, health, and work), which took place in 1996. Participants were randomly drawn from the patient lists of about one hundred occupational physicians in three regions of southern France. The current study concerned 2,768 wage earners born in 1944, 1954, or 1964. The material consisted of 59 questions aimed at assessing a broad set of working conditions, some of which were proxy measures of the dimensions described in the Karasek and Siegrist models.From a principal component analysis, three main factors were extracted that accounted for 40% of the total variance. The first factor (a=0.79) included items that referred to the decision latitude in the Karasek model and items that referred to the reward dimension in the Siegrist model. The second factor (a=0.77) was made up of items tapping physical stressors, while the third factor (a=0.71) pooled items that corresponded fairly well to psychological demands in the Karasek model. Highly significant relationships (p10(-4)) were found between the mean factor scores and both occupational status and educational level, with a lower occupational status and educational level being associated with greater lack of job control and rewards, higher physical stress, but lower psychological demands. Less job control and fewer rewards were also found to be greater in older workers (p10(-3)) and females (p10(-4)).Our results thus confirm the existence of a strong association, in a French cohort, between occupational status and dimensions of job stress known to be associated with adverse health outcomes.

Pacemaker lead infection is a major complication of endovascular permanent pacing. The incidence is less than 1% but it is a frequent disease due to the high number of pacemaker implanted. The diagnosis is difficult due to the insidious symptoms. Pacemaker infection must be systematically considered in patients with a pacemaker and symptoms of infection. Several investigations are useful for the diagnosis particularly the transesophageal echocardiography, but all investigations have a low negative predictive value. All of the implanted material must be completely removed.

The study of an information system related to OSI management applications is described. An information system architecture suitable for the requirements of heterogeneous and distributed management information processing is specified. An ad hoc design approach is proposed for modeling the management information system by generic operational objects. A repository of registered generic definitions is obtained, providing a means to ensure interoperability between management systems. >

Femoral approach pacemaker lead extraction is described as a safe and efficacious procedure. When the lead can not be removed from its myocardial insertion, the "Needle's eye snare" has become available, and it allows a femoral approach traction associated with a countertraction. Between May 1998 and May 2000, 222 lead extraction procedures were performed in 99 patients using the femoral approach. This article reports the results of the 70 lead extractions requiring the use of the Needle's eye snare for femoral approach countertraction in 39 patients with a total of 82 leads. The indications were infection, accufix leads and lead dysfunction in 56, 1 and 6 leads, respectively. The age of the leads was 113 +/- 56 months. Sixty-one (87.2%) leads were successfully extracted, the extraction was incomplete in 3 (4.3%) cases and failed in 6 (8.5%) cases. The failures were due to leads totally excluded from the venous flow for four leads, the impossibility of advancing the 16 Fr long sheath through the right and left iliac veins for one lead and one traction induced a nontolerated ventricular arrhythmia. In these cases, an extraction by a simple upper traction had been attempted in another center several months before. The complications included two deaths and one transient ischemia of the right inferior limb. Despite the selection of a series of leads for which an extraction by a simple traction on the proximal end of the lead was impossible or unsuccessful, femoral countertraction seems to be a safe and efficacious procedure. The failure of this technique occurred in patients with damaged leads due to a previous extraction procedure performed in centers with limited experience in lead extraction.

Following an exhaustive aetiological investigation, 10 to 26% of syncopal attacks remain unexplained. In these cases the correlation between symptoms and rhythm is a deciding step for the aetiological diagnosis. We report our initial experience using an implantable electrocardiographic monitor, a new diagnostic tool in patients suffering from syncope and recurrent unexplained syncopal attacks.The study included 32 patients (average age 55 +/- 22 years; 23 males) suffering from syncope and/or recurrent syncopal attacks remaining unexplained following an exhaustive aetiological investigation. The average follow up was 10.2 +/- 2.5 months. No case of sudden death was registered, and the device was removed in only one patient due to poor tolerance. During follow up, 21 recordings were memorized and analysed in 15 patients (45%), giving an average of 1.4 recordings per patient. The average interval for recurrence of symptoms after implantation was from 84 +/- 104 days, 75% of the episodes coming in the first 2 months following implantation. An arrhythmia was detected on 10 occasions: a malignant ventricular arrhythmia in 2 patients, a non-sustained ventricular tachycardia in 1 patient, a junctional tachycardia in 1 patient, entry into paroxysmal atrial fibrillation in 4 patients, a sinus bradycardia in 1 patient, and a sinus pause for 19 seconds in 1 patient. In one patient ST segment depression was documented following anterior chest pain. The tracing was normal with sinus rhythm recorded on 10 occasions, representing the only documented information in 4 patients. In total, an aetiology was found in 11 of the 32 patients evaluated (34%). Once the aetiological diagnosis was established and a specific treatment initiated, all the patients became asymptomatic.Our preliminary results underline the significance of the implantable ECG monitor in the diagnostic approach to recurrent unexplained syncopal attacks. The exact place of this tool in the decisional algorithm for syncope remains to be defined with further studies.

Sand rats develop obesity, insulin-resistance, hyperlipidemia and prediabetes, when given a standard laboratory chow diet. We have used this model to demonstrate the beneficial action of olea europea var. oleaster leaves to regulate unbalanced metabolism. 32 sand rats fed on hypercaloric diet during 7 months, were divided into 3 groups: controls (n=10), treated by plant (n=13) and treated by simvastatin (Zoco); hypocholesterolemic drug. The plant decoction prepared at 10% was given orally at the rate of 1.5 ml/100g during 3 months. Results show that the plant presents a hypocholesterolemic effect (42%) related to decreases in LDL and VLDL cholesterol. In addition, hypoglycemic (16%) and antihyperglycemic (40%) effects were observed accompanied by a 27% decrease in insulin. Chronic treatment with Zocor reduced total cholesterol (32%), LDL and VLDL cholesterol. Both of treatments produced no significantly reduction in plasma levels of triglycerides and HDL cholesterol. No noxions effect of this plant have been observed in usual doses.