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Chronic spinal cord injury (SCI) is a devastating medical condition. In the acute phase after injury, there is cell loss resulting in chronic axonal damage and loss of sensory and motor function including loss of oligodendrocytes that results in demyelination of axons and further dysfunction. In the chronic phase, the inhibitory environment within the lesion including the glial scar can arrest axonal growth and regeneration and can also potentially affect transplanted cells. We hypothesized that glial scar ablation (GSA) along with cell transplantation may be required as a combinatorial therapy to achieve functional recovery, and therefore we proposed to examine the survival and fate of human induced pluripotent stem cell (iPSC) derived pre-oligodendrocyte progenitor cells (pre-OPCs) transplanted in a model of chronic SCI, whether this was affected by GSA, and whether this combination of treatments would result in functional recovery. In this study, chronically injured athymic nude (ATN) rats were allocated to one of three treatment groups: GSA only, pre-OPCs only, or GSA+pre-OPCs. We found that human iPSC derived pre-OPCs were multi-potent and retained the ability to differentiate into mainly oligodendrocytes or neurons when transplanted into the chronically injured spinal cords of rats. Twelve weeks after cell transplantation, we observed that more of the transplanted cells differentiated into oligodendrocytes when the glial scar was ablated compared with no GSA. Further, we also observed that a higher percentage of transplanted cells differentiated into V2a interneurons and motor neurons in the pre-OPCs only group when compared with GSA+pre-OPCs. This suggests that the local environment created by ablation of the glial scar may have a significant effect on the fate of cells transplanted into the injury site.

BackgroundRegenerating islet-derived protein 3α (REG3α) is an antimicrobial peptide secreted by intestinal Paneth cells. Circulating REG3α has been identified as a gut damage marker in inflammatory bowel diseases. People living with human immunodeficiency virus (PWH) on antiretroviral therapy (ART) present with an abnormal intestinal landscape leading to microbial translocation, persistent inflammation, and development of non-AIDS comorbidities. Herein, we assessed REG3α as a marker of gut damage in PWH.MethodsPlasma from 169 adult PWH, including 30 elite controllers (ECs), and 30 human immunodeficiency virus (HIV)–uninfected controls were assessed. REG3α plasma levels were compared with HIV disease progression, epithelial gut damage, microbial translocation, and immune activation markers.ResultsCross-sectionally, REG3α levels were elevated in untreated and ART-treated PWH compared with controls. ECs also had elevated REG3α levels compared to controls. Longitudinally, REG3α levels increased in PWH without ART and decreased in those who initiated ART. REG3α levels were inversely associated with CD4 T-cell count and CD4:CD8 ratio, while positively correlated with HIV viral load in untreated participants, and with fungal product translocation and inflammatory markers in all PWH.ConclusionsPlasma REG3α levels were elevated in PWH, including ECs. The gut inflammatory marker REG3α may be used to evaluate therapeutic interventions and predict non-AIDS comorbidity risks in PWH.

Neutrophil extracellular traps (NETs) are composed of nuclear DNA in a web-like structure extruded from neutrophils in response to either bacterial infection or inflammation. We previously reported the expression of angiopoietin Tie2 receptor on human neutrophils and the capacity of both angiopoietins (Ang1 and Ang2) to induce proinflammatory activities, such as synthesis and release of platelet-activating factor, upregulation of β2 integrin complex (CD11/CD18), and neutrophil chemotaxis. In contrast, only Ang1 but not Ang2 is capable of promoting translational and transcriptional activities in neutrophils. In this article, we addressed whether Ang1 and/or Ang2 could modulate the release of NETs and if they contribute to angiopoietin-mediated proinflammatory activities. We observed that Ang1 and Ang2, alone or combined (10 nM, 3 h), increase NET synthesis and release by ≈2.5-fold as compared with PBS-treated neutrophils. The release of NETs is Tie2 dependent and requires downstream intracellular participation of PI3K, p38, and p42/44 MAPK pathways; reactive oxygen species production; intracellular calcium store depletion; and protein arginine deiminase 4 activation. These isolated NETs induced neutrophil and endothelial cell activation, leading to neutrophil adhesion onto human extracellular matrix and HUVEC and in vitro formation of capillary-like tubes by endothelial cells. Our study reports the capacity of Ang1 and Ang2 to promote the release of NETs and that these NETs contribute to angiopoietin-mediated in vitro proinflammatory and proangiogenic activities.

The XXL survey currently covers two 25 sq. deg. patches with XMM observations of ~10ks. We summarise the scientific results associated with the first release of the XXL data set, that occurred mid 2016. We review several arguments for increasing the survey depth to 40 ks during the next decade of XMM operations. X-ray (z 1 cluster density. It will eventually constitute a reference study and an ideal calibration field for the upcoming eROSITA and Euclid missions.

C-reactive protein (CRP) is recognized as a biomarker of chronic, low-grade inflammation associated with vascular disorders. Lately, the role of neutrophils and neutrophil extracellular traps (NETs) has been investigated as a potential source of chronic inflammation and cardiovascular complications. This study investigated NETs as a marker of inflammation in patients with symptomatic heart failure (HF) with or without type 2 diabetes (T2DM) and examined the correlation between NETs and CRP. We performed a noninterventional study including patients with HF with or without T2DM, T2DM, and a healthy control (HC) group. NETs and other inflammatory markers in serum were measured by ELISA. The release of NETs (NETosis) in vitro under various stimuli was measured by confocal microscopy. The levels of NETs in the serum of HF patients were significantly higher compared with HC (112%). Serum CRP concentrations were significantly increased in HF and HF plus T2DM patients compared with HC, and a positive correlation was observed between serum CRP and NETs levels. Neutrophils from HF and HF plus T2DM patients underwent in vitro NETs release faster than T2DM and HC without any stimuli. In vitro, serum collected from the HF and the HF plus T2DM group induced NETosis in healthy neutrophils significantly more when compared with HC and T2DM, which was prevented by depletion from CRP. We confirmed in vitro that CRP induces a concentration-dependent NETs synthesis. This study proposes a mechanism by which CRP increases the risk of future cardiovascular events and supports mounting evidences on the role of neutrophils in chronic low-grade inflammation associated with HF.

Background. CD8 T-cell counts remain elevated in human immunodeficiency virus (HIV) infection even after long-term antiretroviral therapy (ART), which is associated with an increased risk of non–AIDS-related events. We assessed the impact of ART initiation in early versus chronic HIV infection on trajectories of CD8 cell counts over time. Methods. Of 280 individuals enrolled during primary HIV infection (PHI), 251 were followed up for 24 months; 84 started ART before 6 months of infection (eART), 49 started between 6 and 24 months, and 118 remained untreated. Plasma HIV viral load (VL), CD4 and CD8 cell counts were assessed at each study visit. CD8 counts were also examined in 182 age-matched HIV-infected individuals who started ART during chronic infection and maintained undetectable plasma VL for ≥5 years. Results. At PHI baseline, higher CD8 cell counts were associated with more recent infection (P = .02), higher CD4 cell counts (P < .001), and higher VL (P < .001). The CD8 count in the eART group decreased from 797 to 588 cells/µL over 24 months (P < .001), to a level lower than that in untreated PHI (834 cells/µL; P = .004) or in long-term–treated patients with chronic HIV infection (743 cells/µL; P = .047). More prominent CD4 T-cell recovery was observed in the eART group than in the delayed ART group. Conclusions. ART initiated in early HIV infection is associated with improved resolution of CD8 T-cell elevation compared with long-term ART initiated in chronic infection. Early ART may help reduce the risk of non–AIDS-related events by alleviating this elevation.

There are no effective therapies available currently to ameliorate loss of function for patients with spinal cord injuries (SCIs). In addition, proposed treatments that demonstrated functional recovery in animal models of acute SCI have failed almost invariably when applied to chronic injury models. Glial scar formation in chronic injury is a likely contributor to limitation on regeneration. We have removed existing scar tissue in chronically contused rat spinal cord using a rose Bengal-based photo ablation approach. In this study, we compared two chemically modified rose bengal derivatives to unmodified rose bengal, both confirming and expanding on our previously published report. Rats were treated with unmodified rose bengal (RB1) or rose bengal modified with hydrocarbon (RB2) or polyethylene glycol (RB3), to determine the effects on scar components and spared tissue post-treatment. Our results showed that RB1 was more efficacious than RB2, while still maintaining minimal collateral effects on spared tissue. RB3 was not taken up by the cells, likely because of its size, and therefore had no effect. Treatment with RB1 also resulted in an increase in serotonin eight days post-treatment in chronically injured spinal cords. Thus, we suggest that unmodified rose Bengal is a potent candidate agent for the development of a therapeutic strategy for scar ablation in chronic SCI.

Neural regeneration devices interface with the nervous system and can provide flexibility in material choice, implantation without the need for additional surgeries, and the ability to serve as guides augmented with physical, biological (e.g., cellular), and biochemical functionalities. Given the complexity and challenges associated with neural regeneration, a 3D printing approach to the design and manufacturing of neural devices could provide next-generation opportunities for advanced neural regeneration via the production of anatomically accurate geometries, spatial distributions of cellular components, and incorporation of therapeutic biomolecules. A 3D printing-based approach offers compatibility with 3D scanning, computer modeling, choice of input material, and increasing control over hierarchical integration. Therefore, a 3D printed implantable platform could ultimately be used to prepare novel biomimetic scaffolds and model complex tissue architectures for clinical implants in order to treat neurological diseases and injuries. Further, the flexibility and specificity offered by 3D printed in vitro platforms have the potential to be a significant foundational breakthrough with broad research implications in cell signaling and drug screening for personalized healthcare. This progress report examines recent advances in 3D printing strategies for neural regeneration as well as insight into how these approaches can be improved in future studies.

Introduction: Our principal aim was to document the feasibility of the systematic measurement of the inter-arm blood pressure difference (IABPD) during an episode of transient ischemic attack (TIA) or mild stroke diagnosed in the Emergency Department (ED). As secondary goal was to compare the systolic blood pressure (BP) at triage with the systolic BPs measured during the IABPD. Methods: This is a single center pilot study. Patients presenting in the ED for a diagnosis of TIA were recruited. Once patient has been triaged and diagnosed of TIA, a research assistant made sure that the patient lay on a stretcher for at least 5 minutes. Two automated sphygmomanometers were applied, on each arm. No specific device or device calibration were required. Three consecutive simultaneous BP readings were performed, inverting cuffs arm to arm between each reading. Only the last two set of readings were used to calculate the mean IABPD. This method enables to minimize the error coming from the potential sphygmomanometers’ inaccuracies. Results: 32 patients were recruited from June to September 2017 and all had a successful IABPD measurement. Four patients had an IABPD >10 mmHg, varying from 1.5 to 13 mmHg when the left arm was higher and from 1 to 61 mmHg when the right arm was higher. Of the 22 patients where the triage BP arm side selection was recorded, only 11 were congruent with the arm presenting the highest BP during the IABPD measurement. Selecting of the arm with the highest BP value may better reflect cerebrovascular risk exposition. The mean systolic BP at triage was 159.3 mmHg (95%CI: 144.9-173.7) compared to144.8 mmHg (95%CI: 132.9-156.7) if the arm with the highest value during the IABPD measurement is selected and 142.4 mmHg (95%CI: 130.8-154.0) if the same arm as triage is selected. The p-value for these differences were 0.003 and 0.001 respectively. The patient which presented the IABPD of 61 mmHg, had a stroke 3 days after its ED visit which subsequently led to her death 10 days later. Conclusion: Our results show that the systematic IABPD measurement using a pragmatic approach in the ED is feasible and is ready to investigate its use in the context of a new TIA or mild stroke. This information may contribute to a better discrimination of the short-term risk of stroke and may help to diagnose acute aortic dissection, monitor more accurately BP during hyperacute stroke or estimate intracerebral hemorrhage risk if systemic thrombolysis is considered.

The growth of brightest cluster galaxies is closely related to the properties of their host cluster. We present evidence for dry mergers as the dominant source of BCG mass growth at $z\lesssim1$ in the XXL 100 brightest cluster sample. We use the global red sequence, H$\alpha$ emission and mean star formation history to show that BCGs in the sample possess star formation levels comparable to field ellipticals of similar stellar mass and redshift. XXL 100 brightest clusters are less massive on average than those in other X-ray selected samples such as LoCuSS or HIFLUGCS. Few clusters in the sample display high central gas concentration, rendering inefficient the growth of BCGs via star formation resulting from the accretion of cool gas. Using measures of the relaxation state of their host clusters, we show that BCGs grow as relaxation proceeds. We find that the BCG stellar mass corresponds to a relatively constant fraction 1\%\ of the total cluster mass in relaxed systems. We also show that, following a cluster scale merger event, the BCG stellar mass lags behind the expected value from the M$_{cluster}$ - M$_{BCG}$ relation but subsequently accretes stellar mass via dry mergers as the BCG and cluster evolve towards a relaxed state., Comment: 16 pages, 13 figues

Traditionally, galaxy clusters have been expected to retain all the material accreted since their formation epoch. For this reason, their matter content should be representative of the Universe as a whole, and thus their baryon fraction should be close to the Universal baryon fraction. We make use of the sample of the 100 brightest galaxy clusters discovered in the XXL Survey to investigate the fraction of baryons in the form of hot gas and stars in the cluster population. We measure the gas masses of the detected halos and use a mass--temperature relation directly calibrated using weak-lensing measurements for a subset of XXL clusters to estimate the halo mass. We find that the weak-lensing calibrated gas fraction of XXL-100-GC clusters is substantially lower than was found in previous studies using hydrostatic masses. Our best-fit relation between gas fraction and mass reads $f_{\rm gas,500}=0.055_{-0.006}^{+0.007}\left(M_{\rm 500}/10^{14}M_\odot\right)^{0.21_{-0.10}^{+0.11}}$. The baryon budget of galaxy clusters therefore falls short of the Universal baryon fraction by about a factor of two at $r_{\rm 500}$. Our measurements require a hydrostatic bias $1-b=M_X/M_{\rm WL}=0.72_{-0.07}^{+0.08}$ to match the gas fraction obtained using lensing and hydrostatic equilibrium. Comparing our gas fraction measurements with the expectations from numerical simulations, our results favour an extreme feedback scheme in which a significant fraction of the baryons are expelled from the cores of halos. This model is, however, in contrast with the thermodynamical properties of observed halos, which might suggest that weak-lensing masses are overestimated. We note that a mass bias $1-b=0.58$ as required to reconcile Planck CMB and cluster counts should translate into an even lower baryon fraction, which poses a major challenge to our current understanding of galaxy clusters. [Abridged], Comment: 13th paper in the XXL series, A&A in press

The XXL Survey is the largest homogeneous and contiguous survey carried out with XMM-Newton. Covering an area of 50 square degrees distributed over two fields, it primarily investigates the large-scale structures of the Universe using the distribution of galaxy clusters and active galactic nuclei as tracers of the matter distribution. Given its depth and sky coverage, XXL is particularly suited to systematically unveiling the clustering of X-ray clusters and to identifying superstructures in a homogeneous X-ray sample down to the typical mass scale of a local massive cluster. A friends-of-friends algorithm in three-dimensional physical space was run to identify large-scale structures. In this paper we report the discovery of the highest redshift supercluster of galaxies found in the XXL Survey. We describe the X-ray properties of the clusters members of the structure and the optical follow-up. The newly discovered supercluster is composed of six clusters of galaxies at a median redshift z around 0.43 and distributed across approximately 30 by 15 arc minutes (10 by 5 Mpc on sky) on the sky. This structure is very compact with all the clusters residing in one XMM pointing; for this reason this is the first supercluster discovered with the XXL Survey. Spectroscopic follow-up with WHT (William Herschel Telescope) and NTT (New Technology Telescope) confirmed a median redshift of z = 0.43. An estimate of the X-ray mass and luminosity of this supercluster and of its total gas mass put XLSSC-e at the average mass range of superclusters; its appearance, with two members of equal size, is quite unusual with respect to other superclusters and provides a unique view of the formation process of a massive structure., A&A, accepted; special XXL issue

We present the XXL Survey, the largest XMM programme totaling some 6.9 Ms to date and involving an international consortium of roughly 100 members. The XXL Survey covers two extragalactic areas of 25 deg2 each at a point-source sensitivity of ~ 5E-15 erg/sec/cm2 in the [0.5-2] keV band (completeness limit). The survey's main goals are to provide constraints on the dark energy equation of state from the space-time distribution of clusters of galaxies and to serve as a pathfinder for future, wide-area X-ray missions. We review science objectives, including cluster studies, AGN evolution, and large-scale structure, that are being conducted with the support of approximately 30 follow-up programmes. We describe the 542 XMM observations along with the associated multi-lambda and numerical simulation programmes. We give a detailed account of the X-ray processing steps and describe innovative tools being developed for the cosmological analysis. The paper provides a thorough evaluation of the X-ray data, including quality controls, photon statistics, exposure and background maps, and sky coverage. Source catalogue construction and multi-lambda associations are briefly described. This material will be the basis for the calculation of the cluster and AGN selection functions, critical elements of the cosmological and science analyses. The XXL multi-lambda data set will have a unique lasting legacy value for cosmological and extragalactic studies and will serve as a calibration resource for future dark energy studies with clusters and other X-ray selected sources. With the present article, we release the XMM XXL photon and smoothed images along with the corresponding exposure maps. The XMM XXL observation list (Table B.1) is available in electronic form at the CDS. The present paper is the first in a series reporting results of the XXL-XMM survey., Comment: 17 pages, accepted in A&A

We present the K-band luminosity-halo mass relation, $L_{K,500}-M_{500,WL}$, for a subsample of 20 of the 100 brightest clusters in the XXL Survey observed with WIRCam at the Canada-France-Hawaii Telescope (CFHT). For the first time, we have measured this relation via weak-lensing analysis down to $M_{500,WL} =3.5 \times 10^{13}\,M_\odot$. This allows us to investigate whether the slope of the $L_K-M$ relation is different for groups and clusters, as seen in other works. The clusters in our sample span a wide range in mass, $M_{500,WL} =0.35-12.10 \times 10^{14}\,M_\odot$, at $0, Comment: A&A, in press

Imaging Fourier transform spectroscopy (iFTS) is a promising, although technically very challenging, option for wide-field hyperspectral imagery. We present in this paper an introduction to the iFTS concept and its advantages and drawbacks, as well as examples of data obtained with a prototype iFTS, SpIOMM, attached to the 1.6 m telescope of the Observatoire du Mont-Mégantic: emission line ratios in the spiral galaxy NGC 628 and absorption line indices in the giant elliptical M87. We conclude by introducing SpIOMM's successor, SITELLE, which will be installed at the Canada-France-Hawaii Telescope in 2014.

Phenomenological research indicates that disturbance of the basic sense of self may be a core phenotypic marker of schizophrenia spectrum disorders. Basic self-disturbance refers to disruption of the sense of ownership of experience and agency of action and is associated with a variety of anomalous subjective experiences. Little is known about the neurocognitive underpinnings of basic self-disturbance. In these two theoretical papers (of which this is Part 2), we review some recent phenomenological and neurocognitive research and point to a convergence of these approaches around the concept of self-disturbance. Specifically, we propose that subjective anomalies associated with basic self-disturbance may be associated with: 1. source monitoring deficits, which may contribute particularly to disturbances of "ownership" and "mineness" (the phenomenological notion of presence or self-affection) and 2. aberrant salience, and associated disturbances of memory, prediction and attention processes, which may contribute to hyper-reflexivity, disturbed "grip" or "hold" on perceptual and conceptual fields, and disturbances of intuitive social understanding ("common sense"). In this paper (Part 2) we focus on aberrant salience. Part 1 (this issue) addressed source monitoring deficits. Empirical studies are required in a variety of populations in order to test these proposed associations between phenomenological and neurocognitive aspects of self-disturbance in schizophrenia. An integration of findings across the phenomenological and neurocognitive "levels" would represent a significant advance in the understanding of schizophrenia and possibly enhance early identification and intervention strategies.

Introduction The Clinical and Laboratory Standards Institute recently published M53-A, Criteria for Laboratory Testing and Diagnosis of Human Immunodeficiency Virus ( HIV ) Infection ; Approved Guideline (2011), which includes a state of the art algorithm for identifying HIV-1 acute and HIV-2 infections. To assess the ability of Canadian laboratories to detect these sample types and the impact of M53-A, the National Laboratory for HIV Reference Services distributed a special proficiency testing panel. Methods HIVS425-2012Nov22 was sent to 42 laboratories across Canada. It contained one HIV negative sample (B), two HIV-1 positive samples (A and E), one HIV-2 positive sample (C) and one HIV-1/2 antibody negative-HIV-1 antigen positive sample (D). Data was collected and analyzed using DigitalPT; a standardized on-line tool. Results Forty-one laboratories returned results. Sample B (HIV negative) was identified by 95% of laboratories (39/41) and samples A and E (HIV-1 positive) by 98% (40/41). No laboratory identified sample C as HIV-2 positive, although 85% (35/41) detected reactivity prompting a referral for further testing. The remaining laboratories identified sample C as HIV-1 positive (4), indeterminate (1) or gave no final status (1). Sample D (HIV antibody negative-antigen positive) was correctly identified by two laboratories as HIV-1 antigen positive while 78% (32/41) detected reactivity, recommending further testing. One laboratory did not provide a final status. Alarmingly, six laboratories called this sample HIV negative. Conclusion Although there is a high quality of HIV testing across Canada, introduction of the M53-A guideline would further improve the ability of laboratories to diagnose HIV-1 acute and HIV-2 infection.

The XXL survey is the largest survey carried out by XMM-Newton. Covering an area of 50deg$^2$, the survey contains $\sim450$ galaxy clusters out to a redshift $\sim$2 and to an X-ray flux limit of $\sim5\times10^{-15}erg\,s^{-1}cm^{-2}$. This paper is part of the first release of XXL results focussed on the bright cluster sample. We investigate the scaling relation between weak-lensing mass and X-ray temperature for the brightest clusters in XXL. The scaling relation is used to estimate the mass of all 100 clusters in XXL-100-GC. Based on a subsample of 38 objects that lie within the intersection of the northern XXL field and the publicly available CFHTLenS catalog, we derive the $M_{WL}$ of each system with careful considerations of the systematics. The clusters lie at $0.1, Comment: to be published in A&A

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field. © 2012 Landes Bioscience.

This paper presents a new 6-DOF serial manipulator with five revolute joints and one prismatic joint, designed to operate equipment inside Hydro-Quebec underground distribution vaults. The manipulator is an upgraded model developed after field testing a 6-DOF wrist-partitioned serial manipulator prototype. The new manipulator architecture is intended to solve space constraint problems in some vaults. This paper covers the geometrical model of the new manipulator, an analytical solution for the inverse kinematic equations, the dynamic model used to compute torques/forces at the actuators, and simulations performed with MATLAB and CATIA. The manipulator is the only robot application in the world designed to operate equipment on underground distribution power lines.

This video summarizes the R&D phases of the first robot prototype designed to operate and maintain equipment in vaults for Hydro-Quebec's underground distribution lines, carried out between 2003 and 2009. Detailed segments discuss project's context, proof of concept, simulations, description and design of robotic platform subsystems, prototype testing at IREQ in the lab and in an outdoor vault, field testing in Montreal on a Joslyn switch in a de-energized vault, and the future of the project.

This paper presents a new robot prototype for the construction of Hydro-Quebec's overhead distribution lines. It details the main sub-systems of the robot, such as the climbing system (for climbing poles), the crossarm manipulation system (which handles crossarms and selects tools for drilling holes and inserting bolts), and the bolting system (for fixing crossarms and braces on poles). The robot is made to ascend and descend a pole by teleoperation, and the installation of a pre-assembled crossarm (with brace, pins, insulators and clamps) at the top of a 40-foot pole is performed in full automatic mode. Tests have demonstrated the efficiency of this robotized construction method in installing the line hardware of a three-phase distribution line on a 40-foot pole in 25 minutes.

This paper describes a R&D project at Hydro-Quebec's Research Institute (IREQ) regarding the development of a mobile robot for underground distribution lines. It discusses the advantages of a robotic system for the operation and maintenance of power distribution lines. The tasks to be performed on a Joslyn load break switch located in an underground vault are given, and the prototype of the robot system with its main sub-systems is presented. Field tests with this robot system at IREQ's vault and at a de-energized vault of the distribution network in Montreal are commented.

This paper discusses the work accomplished for the development of a new mobile robotic platform for the Hydro-Quebecpsilas underground power distribution lines. After an overview of few past robotic systems elaborated for the distribution networks, this article details the systems of the mobile robotic platform which seems to be the first in the literature dedicated to the underground distribution lines. We present the vehicle with an articulated chassis selected for this research project to reach the site of an underground vault of the Hydro-Quebecpsilas distribution network. Then, we describe a five-degree-of-freedom hydraulic arm that is assembled on the vehicle and designed to go down in an underground vault. We present the specific tools made for the operation and maintenance of an underground switch. The different tools are handled by a six-degree-of-freedom electric manipulator with integrated electronics especially designed for this project. We discuss the geometrical architecture, the mechanical design, and the kinematic and dynamic simulations of this manipulator. The first experimental tests were successfully performed in November and December 2007 at the Hydro-Quebecpsilas Research Institute site in a simulated vault where the tasks on the underground switch were done in an automatic mode (no teleoperation) supervised by the operator.

The safe control of walking over different terrains requires appropriate adaptations in the dynamic and kinematic limb patterns. To date, the study of locomotor dynamics in the cat has been confined to level, unobstructed walking. The present study extends the work of Lavoie et al. by applying linked segment analyses to estimate muscle contributions to torque and mechanical power at the hindlimb joints of two female cats during both unobstructed walking and obstacle avoidance. Data during obstacle avoidance were analyzed both when the hindlimb led in clearance and was farthest from the obstacle, and when it trailed in clearance and was closest or near to the obstacle. It was found that, in both the Far and Near obstructed conditions, the cats cleared the obstacles primarily by increasing the knee flexor torque already used during unobstructed gait. Contributions from the hip and ankle muscle groups were more variable. There was more emphasis on the hip extensors in mid to late stance, and the hip flexors generated a small amount of energy at paw-lift in the Far condition. In the Near condition, the hip extensors were employed to control hip flexion. We suggest that hip flexor generation power in mid-swing contributes to the clearance of the upcoming obstacle in the Far condition while, in the Near condition, hip flexion advances the already extended limb ahead of the obstacle. The ankle was actively dorsiflexed in the Near condition but was maintained in extension in the Far condition. The emphasis on active knee flexor control by the cat to avoid obstacles, as well as the dependence of ankle control on obstacle proximity, is similar to strategies seen for humans. However, the knee flexor strategy is innate to the cat’s normal level walking control, whereas in humans active knee flexion at toe-off requires a reorganization from level, non-obstructed gait.

A controlled trial of cyclosporine in patients diagnosed with progressive membranous nephropathy (MGN) was carried out to determine whether cyclosporine (D) would be more effective than placebo (P) in reducing the rate of deterioration in renal function. Patients (N = 64) with MGN were placed on a restricted protein diet (or = 0.9 g/kg) and followed closely for 12 months (Part 1). Patients at high risk of progression based on an absolute loss in creatinine clearance (CCr) ofor = 8 ml/min and persistent nephrotic range proteinuria (Pr) were selected and randomly assigned to either (D) (N = 9) or (P) (N = 8) for 12 months (Part 2). No differences in the two groups were noted at entry. After 12 months, the improvement in CCr slope in ml/min/month was significantly greater in the D patients (D + 2.1 vs. P + 0.5, mean difference 1.6; 95% CI 0.3 to 3.0, P0.02). This improvement was maintained in six of eight D (75%) over a mean follow-up period of 21 months. Daily Pr also improved with D (by month 3, D - 4.5 g/day vs. P + 0.7 g/day, P = 0.02) and was sustained in six of eight (75%) D patients. When Pr was expressed as a function of their concurrent CCr, the D versus P patients' time to halving was faster (P = 0.02) and absolute number higher (4/9 D vs 0/8 P). In the D group a trend towards worse hypertension and an increase in the number of transient rises in serum creatinine were noted.(ABSTRACT TRUNCATED AT 250 WORDS)

A 31-year-old, obese woman with extrameningeal cryptococcal disease was admitted to the Medical College of Virginia for antifungal therapy. Various physiologic variables influence flucytosine pharmacokinetics, and there are no guidelines for dosing the agent in obese patients. This patient received a dosage based on her ideal body weight, and serum drug concentrations were monitored. She recovered without sequelae.

The ethos of the neuroimaging field is quickly moving towards the open sharing of resources, including both imaging databases and processing tools. As a neuroimaging database represents a large volume of datasets and as neuroimaging processing pipelines are composed of heterogeneous, computationally intensive tools, such open sharing raises specific computational challenges. This motivates the design of novel dedicated computing infrastructures. This paper describes an interface between PSOM, a code-oriented pipeline development framework, and CBRAIN, a web-oriented platform for grid computing. This interface was used to integrate a PSOM-compliant pipeline for preprocessing of structural and functional magnetic resonance imaging into CBRAIN. We further tested the capacity of our infrastructure to handle a real large-scale project. A neuroimaging database including close to 1000 subjects was preprocessed using our interface and publicly released to help the participants of the ADHD-200 international competition. This successful experiment demonstrated that our integrated grid-computing platform is a powerful solution for high-throughput pipeline analysis in the field of neuroimaging.

Background It was estimated in 2005 that 13% of men who have sex with men (MSM) in Montreal were HIV-positive, and that 23% of these were not aware of their diagnosis. Clinique l9Actuel introduced a pilot rapid HIV testing program using the MedMira kit in 2008. The objective of this study was to describe the sensitivity and specificity of rapid HIV tests in a community based, high HIV risk setting. Methods An advertising campaign encouraged MSM and others at risk for HIV to undergo testing through dedicated clinics offering rapid HIV tests. Patients calling for testing deemed at high risk were given appointments within 2 weeks, where they filled out a short questionnaire, received medical consultation routine STI screening, pre- and post- test counselling and their HIV test results within the hour. Those consenting received with a MedMira or and INSTI rapid test and regular HIV screening. Any positive result was confirmed by Western blot. Results 2500 individuals were tested: 98% men with a median age of 34 (IQR: 26–41). For the MedMira test there were 43 true positives, 2295 true negatives, 13 false positives and four false negatives. 145 patients received the finger-prick INSTI test giving two true positives and 143 true negatives. For MedMira, sensitivity was 91.5% and specificity 99.5% while both figures were 100% for INSTI. The four false negatives were also negative by standard ELISA but positive for P24 antigen. Patients testing positive for HIV had significantly more history of previous STI than those testing negative (p=0.041). Conclusion In this setting sensitivity and specificity of the rapid tests used was comparable to standard testing. Acute seroconversion likely explains the four false negatives. As with conventional testing, rapid testing requires adequate counselling about the possibilities of a false negative test. In high-risk populations, routine STI screening should always be performed together with HIV screening.

Background In Quebec it is estimated that 1/3 of those infected do not know their HIV status, that HIV is diagnosed late in 41%, and that sex during primary infection is an important driver of the epidemic. In late 2008 Clinique l9Actuel launched a testing campaign tailored to MSM in Montreal using free rapid tests with the goal of increasing early diagnosis of HIV. In this study we evaluated the feasibility of and potential impact of facilitated access to rapid HIV-testing. Methods Rapid HIV-tests offered through dedicated clinics were widely advertised in Montreal9s MSM community. Patients calling for testing deemed at high risk were given appointments within 2 weeks, where they filled out a short questionnaire, received medical consultation routine STI screening, pre- and post-test counselling and their HIV test results within the hour. Ongoing support, care, and treatment were offered to those testing positive. Results Over 9 months 2500 received HIV testing. 98% were men and median age was 34 (IQR=26–41). Of these patients, 42% were new to the clinic, 10% had never been tested previously, and 29% had not been tested within the past 2 years. 93% reported they were more likely to undergo repeat screening because of rapid testing. 2% were found to be HIV positive. Of these, 60% cited the rapid test as the primary reason for undergoing screening. 33% of those testing positive were in primary infection, as compared to 18% the previous year at Clinique l9Actuel (p=0.062) and 11% in Quebec. Conclusion Facilitated access to rapid HIV testing can increase uptake in high-risk patients. This may increase early HIV diagnosis and intervention to decrease transmission.

Methods A retrospective analysis of the clients who attend the “Gay Screening Clinic” (GSC) at Clinique medical l9Actuel (Montreal, Canada) between May 2009 and April 2010 was conducted. Results Among the 1010 patients included in the analyses we found five cases of new HCV infection which seems to be acquired by sexual transmission. All of them were male and MSM, none of the cases had previous history of IDU, but three reported having had sexual relation with IDU partners. All of them were previously vaccinated for Hepatitis A and B and screened for HIV. None of them were coinfected with HIV, but one was coinfected with Syphilis and one with Gonorrhoea. Patients infected with HCV were older than non HCV patients (37 years vs 32 years) and had a higher number of sexual partners during the last 12 months (16 part. vs 9 for the non HCV patients). One of the HCV cases reported not having anal intercourse, two reported having had occasional unprotected anal intercourse and two reported always using condom for anal intercourse. Conclusions As in other urban centers, cases of sexually transmitted HCV had also been found in Montreal. This prevalence of 0.5% is very low compared to our HIV population in which the prevalence of sexually transmitted HCV is 3%. The particularity of MSM with recently acquired HCV by sexual transmission seems to be related to their engagement in sexual relation with high number of concurrent partners.

A multi-channel surround sound system and method is described that allows automatic and independent calibration and adjustment of the frequency, amplitude and time response of each channel of the surround sound system. The disclosed auto-calibrating surround sound (ACSS) system includes a processor that generates a test signal represented by a temporal maximum length sequence (MLS) and supplies the test signal as part of an electric input signal to a loudspeaker. A microphone coupled to the processor receives the signal in a listening environment. The processor correlates the received sound signal with the test signal in the time domain and determines from the correlated signals a whitened response of the audio channel in the listening environment.

A simple apparatus for inducing vibrations in strings is presented. The apparatus can be used to excite linear vibrations as well as parametric oscillations in a string under tension. The apparatus consists of an inductive transducer which can be arranged to induce transverse vibrations or to modulate the tension in the string which causes parametrically excited waves. Resonance phenomena in the drive transducer can also be demonstrated.

We identified on the membrane of mouse spleen cells a polypeptide of Mr 190,000 (S190), with binding affinity for the mouse third component of the complement system (C3). S190, purified by affinity chromatography on C3-Sepharose, has properties resembling those of the human C3 receptor type 1 (CR1). Thus, S190, like CR1, served as a cofactor for the C3b inactivator (I)-mediated cleavage of fluid-phase C3b into iC3b, and had cofactor activity comparable to that of serum factor H (H). S190 also acted as a cofactor for the cleavages of membrane-bound C3b or membrane-bound iC3b into C3c (Mr 140,000) and C3dg (Mr 40,000) by serum factor I. As is the case with CR1, the specific activity of S190 for the cleavages leading to C3c-C3dg formation was approximately 100-fold greater than that of H. We therefore conclude that S190 and CR1 are analogous proteins.

sixty-one new continuous ambulatory peritoneal dialysis (CAPD) patients were allocated to a Y connector disinfectant (Amuchina, Italy) and 63 to standard systems (Baxter Systems II & III) in a randomized clinical trial addressing peritonitis rates in 8 CAPD programs in 6 Canadian cities. In the Y connector-disinfectant group, 15 patients experienced 21 episodes of peritonitis in 452 patient-months or 1 per 21.53 patient-months. In the standard systems group, 30 patients experienced 47 episodes of peritonitis in 467 patient-months or 1 per 9.93 patient-months ( p = 0.009). The peritonitis risk reduction was 61% (95% confidence limits 27–79%). Exit-site infections occurred in 36% of each group. Prior to the development of exit -site infection, the monthly risk for peritonitis was 3.12% for the Y connector disinfectant system and 7.37% for the standard system. After an exit -site infection, these probabilities increased to 6.15% and 15.47%, respectively. Skin organisms were responsible for peritonitis in 8/21 (38%) in the Y connector-disinfectant group and 30/47 (64%) in the standard group. There were 75 days hospitalized for peritonitis in the Y connector-disinfectant group compared to 257 days for the standard group. The Y connector disinfectant system decreases the peritonitis rate through its effect on skin organisms. Exit -site infections are a major source of organisms responsible for peritonitis.

Oculopharyngeal muscular dystrophy (OPMD) is an autosomal dominant transmitted condition seen mainly in the French Canadian population. Twenty-one patients with an established diagnosis of this rare disease underwent inferior constrictor myotomy. All patients were evaluated clinically and 12 of them underwent pharyngoesophageal manometric evaluation both preoperatively and postoperatively. All patients presented with severe oropharyngeal dysphagia and frequent aspiration together with pharyngooral and pharyngonasal regurgitation. Our results showed that all symptoms were significantly improved after inferior constrictor myotomy. Manometric assessment showed significant differences in pressure, duration and frequency of pharyngeal contraction when compared with a control group. After surgery pharyngeal contraction frequency was significantly lowered toward the normal level but other parameters of pharyngeal function remained unchanged. At the level of the upper esophageal sphincter, resting and closing pressure, relaxation time, relaxation and coordination were studied. There was no significant difference between control subjects and OPMD patients for these variables. Surgery significantly lowered the resting and closing pressure of the sphincter but did not modify significantly the other parameters.

Twenty-three patients with progressive systemic sclerosis (PSS) were studied by radionuclide esophageal transit (RT) and esophageal manometry. Twenty-two patients had abnormal manometry ranging from lower esophageal sphincter incompetence to aperistaltism. Of these 22 patients, twenty (91%) had abnormal RT with prolongation of transit time. A characteristic RT pattern showing stagnation of the radionuclide in the distal and middle segments of the esophagus was demonstrated in 82% of the patients with advanced sclerodermatous involvement of the esophagus. Fifteen of the 19 controls (79%) studied had a normal RT. Four showed prolongation of transit time without stagnation. We conclude that RT is a safe, noninvasive, highly sensitive method which might be used as an alternative to esophageal manometry. However, it may lack specificity.

We identified on the membrane of mouse spleen cells a polypeptide of Mr 190,000 (S190), with binding affinity for the mouse third component of the complement system (C3). S190, purified by affinity chromatography on C3-Sepharose, has properties resembling those of the human C3 receptor type 1 (CR1). Thus, S190, like CR1, served as a cofactor for the C3b inactivator (I)-mediated cleavage of fluid-phase C3b into iC3b, and had cofactor activity comparable to that of serum factor H (H). S190 also acted as a cofactor for the cleavages of membrane-bound C3b or membrane-bound iC3b into C3c (Mr 140,000) and C3dg (Mr 40,000) by serum factor I. As is the case with CR1, the specific activity of S190 for the cleavages leading to C3c-C3dg formation was approximately 100-fold greater than that of H. We therefore conclude that S190 and CR1 are analogous proteins.