Three‐Dimensional Time‐Lapse Geoelectrical Monitoring of Water Infiltration in an Experimental Mine Waste Rock Pile

Open-pit mines often generate large quantities of waste rocks that are usually stored in waste rock piles (WRPs). When the waste rocks contain reactive minerals (mainly sulfides), water and air circulation can lead to the generation of contaminated drainage. An experimental WRP was built at the Lac Tio mine (Canada) to validate a new disposal method that aims to limit water infiltration into reactive waste rocks. More specifically, a flow control layer was placed on top of the pile, which represents a typical bench level, to divert water toward the outer edge. Hydrogeological sensors and geophysical electrodes were installed for monitoring moisture distribution in the pile during infiltration events. A three-dimensional (3D) time-lapse hydrogeophysical monitoring program was conducted to assess water infiltration and movement. Readings from the 192 circular electrodes buried in the WRP were used to reconstruct the 3D bulk electrical resistivity (ER) variations over time. A significant effort was devoted to assessing the spatiotemporal evolution of water ER because the bulk ER is strongly affected by water quality (and content). The water ER was used as a tracer to monitor the infiltration and flow of resistive and conductive waters. The results indicate that the inclined surface layer efficiently diverts a large part of the added water away from the core of the pile. Local and global models of water infiltration explaining both bulk and water ER variations are proposed. The results shown here are consistent with hydrogeological data and provide additional insights to characterize the behavior of the pile

Comment protéger la santé des travailleurs dans un système qui ne repose pas sur les notions d’aptitude et d’inaptitude ?

Au Québec, en santé au travail, l’approche de santé publique a été privilégiée à l’approche médicale individuelle, parce qu’elle est conséquente aux objectifs de la loi, à savoir la prise en charge par le milieu de ses problèmes et la diminution, voire l’élimination des dangers. Quant aux activités médicales individuelles, elles ne sont réalisées que lorsqu’elles sont légitimes, c’est-à-dire lorsque leur pertinence et leur efficacité sur le plan de la prévention ont été démontrées. Quelques évaluations l’ont confirmé, l’approche par programme des services de santé publique québécois fonctionne en général très bien et elle est efficace. Mieux que l’examen médical de chaque sujet, elle permet de centrer les énergies sur les expositions professionnelles et les composantes de l’organisation du travail susceptibles de provoquer des problèmes. Malgré toutes ses qualités, le système de santé au travail québécois se heurte à de sérieuses résistances institutionnelles et politiques qui ont compromis son développement et mènent progressivement à son essoufflement.In Québec, in occupational health, the public health approach has been favoured over the individual medical approach because it is consistent with the objectives of the law, namely this community taking charge of its problems, and the reduction and even elimination of risk factors. Individual medical activities are limited to cases where the relevance and effectiveness of preventive benefits have been demonstrated. Some evaluative studies have shown that this Québec public health program approach works well in general, and is effective. Compared with the medical examination of each subject, it has a better potential for focusing energies on occupational exposures and on work organizational factors that could cause problems. Despite all its advantages, the Québec occupational health system is facing serious institutional and political resistance that has compromised its development and is gradually leading it to its dysfunction.En Quebec, en salud laboral, el enfoque de salud pública ha favorecido el enfoque médico individual, porque éste es consecuente con los objetivos de la Ley, a saberse : la asunción por parte del medio de sus problemas y la disminución o eliminación de los riesgos. En cuanto a las actividades médicas individuales, estas no son realizadas sino una vez que son legitimas, le que quiere decir que se realizan cuando es demostrada su pertinencia y eficacia en el plano de la prevención. Algunas evaluaciones han confirmado que el enfoque por programa de servicios de salud pública en Quebec funciona muy bien y es eficaz. Mejor que el examen médico individual, este programa permite concentrar las energías en las exposiciones profesionales y en los componentes de la organización de trabajo que podrían provocar problemas. A pesar de todas sus cualidades, el sistema de salud laboral de Quebec, afronta serias oposiciones institucionales y políticas que han comprometido su desarrollo y conducen progresivamente a su estancamiento

Development and inter-rater reliability of a tool assessing hypnotic communication behaviours adopted by nurses caring for children with cancer : The Sainte-Justine Hypnotic Communication Assessment Scale

Background Several studies in pediatric oncology have shown the successful effects of using hypnotic communication techniques (HCTech) during painful medical procedures. Since no studies assessed the precise use of these techniques with a validated tool, it is unsure that the observed relationships involve the use of HCTech. Objectives To develop a scale evaluating healthcare professionals’ behaviours when using HCTech and to evaluate its inter-rater reliability. Methods This study involved the preliminary steps of the Sainte-Justine Hypnotic Communication Assessment Scale (SJ-HCAS) development process. As part of a larger intervention study, the SJ-HCAS was developed in three steps by five experts and four lay raters using an iterative process applied to subsets of video-recorded nurse-patient interactions. The development aimed to maximize clarity and precision of items as well as minimize redundancy amongst items. Inter-rater reliability was assessed in a randomly selected sample of 1/3 of collected video-recorded interactions (n = 42). Results The final version of the scale is composed of 11 items categorized in two domains pertaining to Relationship and Technique. We found excellent inter-rater reliability for both subscores and total score in two independent inter-rater comparisons (median ICC = 0.879), with most items showing very good to perfect inter-rater reliability (median Kappa = 0.847). Conclusions The results support further work with the SJ-HCAS. The scale has the potential to help ensure the integrity of hypnotic communication training in children which could ultimately promote the dissemination of the practice of HCTech

Do professionals change their communication behaviours following a training in hypnosis-derived communication? : a feasibility study in pediatric oncology

Objectives The purpose of this study was to test the feasibility of a training in hypnotic communication techniques (HCTech) for pediatric nurses to prevent procedural pain and distress in children during venipunctures. Specifically, this study aimed to (1) assess nurses’ mastery of HCTech and (2) nurses’ experience regarding the training program. Methods Participants were 6 female pediatric nurses and 33 of their cancer patients. Nurses took part in a 4-day theoretical and practical training in HCTech. Venipuncture procedures were video-recorded and assessed to evaluate nurses’ mastery of HCTech using a standardized scale. Pre-training use of HCTech was compared with post-training and follow-up for the entire nurse sample and across nurses with the same patients (109 nurse-patient interactions). After the follow-up, nurses were questioned about their experience in regards to the training and activities (themes and practice). Results Results showed medium pre-post changes in hypnotic communication behaviours (pre-post d = 0.74), with changes maintaining at follow-up (pre-follow-up d = 0.97). Interviews transcripts’ analyses revealed moderate levels of motivation and satisfaction regarding the training content and format. Nurses suggested to emphasize on the practice of HCTech in a noisy outpatient clinic as well as offer more practical exercises. Conclusion A 4-day training in hypnotic communication techniques translated into the use of HCTech by nurses practicing in pediatric oncology when comparing the same dyads at baseline, post-training and follow-up. Results support further refinement and suggest nurses could be trained to prevent pain and distress with hypnosis-derived communication strategies

Does practising hypnosis-derived communication techniques by oncology nurses translate into reduced pain and distress in their patients? : an exploratory study

Objectives: To explore the effects of a hypnotic communication (HC) training for pediatric nurses in decreasing patients’ pain and distress during venipunctures. Methods: A 4- day theoretical and practical HC training was offered to 5 pediatric oncology nurses. The effects of HC were tested with 22 young cancer patients (13 girls, 9 boys, 10±4 years) over 4 timepoints, with 88 encounters being video-recorded and coded in stable professional-patient dyads. Patients’ pain and distress were rated by patients and parents with visual analogue scales and coded from recordings using the Faces, Legs, Activity, Cry and Consolability (FLACC) scale. Results: We observed a significant decrease in pre-post distress reported by parents (d=0.45, p=0.046). Two (out of 5) nurses with higher skills acquisition had larger reduction in patients’ self-reported pain (d=1.03, p=0.028), parents perceived pain (d=1.09, p=0.042), distress (d=1.05, p=0.043) as well as observed pain (d=1.22 p=0.025). Favorable results on pain and distress did not maintain at follow-up. Conclusion and clinical implications: Training nurses in HC may translate into improved pain and distress in patients, both self-rated and observed provided that skills are used in practice. HC training is a promising non-pharmacological intervention to address pain in pediatrics

Electric potential across epidermis and its role during wound healing can be studied by using an in vitro reconstructed human skin

Background : After human epidermis wounding, transepithelial potential (TEP) present in nonlesional epidermis decreases and induces an endogenous direct current epithelial electric field (EEF) that could be implicated in the wound re-epithelialization. Some studies suggest that exogenous electric stimulation of wounds can stimulate healing, although the mechanisms remain to be determined. The Problem : Little is known concerning the exact action of the EEF during healing. The mechanism responsible for TEP and EEF is unknown due to the lack of an in vitro model to study this phenomenon. Basic Science Advances : We carried out studies by using a wound created in a human tissue-engineered skin and determined that TEP undergoes ascending and decreasing phases during the epithelium formation. The in vitro TEP measurements over time in the wound were corroborated with histological changes and with in vivo TEP variations during porcine skin wound healing. The expression of a crucial element implicated in Na+ transport, Na+/K+ ATPase pumps, was also evaluated at the same time points during the re-epithelialization process. The ascending and decreasing TEP values were correlated with changes in the expression of these pumps. The distribution of Na+/K+ ATPase pumps also varied according to epidermal differentiation. Further, inhibition of the pump activity induced a significant decrease of the TEP and of the re-epithelization rate. Clinical Care Relevance : A better comprehension of the role of EEF could have important future medical applications regarding the treatment of chronic wound healing. Conclusion : This study brings a new perspective to understand the formation and restoration of TEP during the cutaneous wound healing process

Identification of functional microRNAs released through asymmetrical processing of HIV-1 TAR element†

The interaction between human immunodeficiency virus type 1 (HIV-1) and RNA silencing pathways is complex and multifaceted. Essential for efficient viral transcription and supporting Tat-mediated transactivation of viral gene expression, the trans-activation responsive (TAR) element is a structured RNA located at the 5′ end of all transcripts derived from HIV-1. Here, we report that this element is a source of microRNAs (miRNAs) in cultured HIV-1-infected cell lines and in HIV-1-infected human CD4+ T lymphocytes. Using primer extension and ribonuclease (RNase) protection assays, we delineated both strands of the TAR miRNA duplex deriving from a model HIV-1 transcript, namely miR-TAR-5p and miR-TAR-3p. In vitro RNase assays indicate that the lack of a free 3′ extremity at the base of TAR may contribute to its low processing reactivity in vivo. Both miR-TAR-5p and miR-TAR-3p down-regulated TAR miRNA sensor activity in a process that required an integral miRNA-guided RNA silencing machinery. miR-TAR-3p exerted superior gene downregulatory effects, probably due to its preferential release from HIV-1 TAR RNA by the RNase III Dicer. Our study suggests that the TAR element of HIV-1 transcripts releases functionally competent miRNAs upon asymmetrical processing by Dicer, thereby providing novel insights into viral miRNA biogenesis