Stabilization of electric arc furnace dust by the use of cementitious materials: Ionic competition and long-term leachability

Ionic competition in stabilization of major heavy metals from electric arc furnace dust (EAFD) was investigated. The cementitious materials tested (ground granulated blast furnace slag (GGBFS) and ordinary Portland cement (OPC)) were put in contact with solutions made of various combinations of Cr(VI), Pb(II), Zn(II), Ni(II) and Mo(VI) ions. The presence of Ni, Zn or Mo did not influence the Cr fixation by GGBFS and OPC. The ionic competition phenomenon between Cr and Pb was observed for GGBFS in particular.Long-term leaching tests with OPC-EAFD and GGBFS-EAFD showed that OPC is more effective in fixing Cr at 7 days (4.7 mg/L in solution) than GGBFS (79.4 mg/L in solution). GGBFS becomes effective with time and offers a better performance from 56 to 365 days (under 1 mg/L in solution) than OPC (until 11 mg/L in solution). GGBFS and OPC decreased Zn, Pb and Ni concentrations in leaching solutions under 2.5 mg/L.     

Review of Les troubles liés aux événements traumatiques: Dépistage, évaluation et traitements.

Reviews the book, Les troubles liés aux événements traumatiques: Dépistage, évaluation et traitements by Stéphane Guay and André Marchand (2006). By the variety and the depth of the fields which it covers, there is no doubt that this volume will prove to be the reference work of choice of French language as regards knowledge on PTSD. This collection, under the direction of Stéphane Guay and André Marchand, made state of current knowledge on the post-traumatic state of stress (PTSD) and gathers the collaboration of various specialists in mental health all connected by their work in the field in of PTSD. It acts of the first work of this style, as much in the French language that English, which makes it possible to gather in a whole current knowledge on various aspects of the phenomenon of the psychological trauma while bringing a critical and exhaustive analysis there. Moreover, contrary to other works on the subject, particularly of English language, this one does not limit itself simply to a specific group of victims of the disorder of PTSD. By the diversity of its contents, this volume will be able to meet the needs for a variety of people as much university clinicians, researchers, professors and students like interesting speakers on the subject or working near the traumatic victims of events. This work gathers 14 chapters written in the form of critical reviews of the writings. The reader will appreciate at the same time the uniformity between the chapters in the presentation, the form and the style of writing and the absence of redundancy in the contents from one chapter to another in spite of the sometimes similar fields. The chapters are comprised of clearly identified sub-sections. Each chapter finishes by proposing therapeutic aims or recommendations and by suggesting tracks of future research. Like any review, each chapter is accompanied by a list by bibliographical references. The whole of the work is written in an open language and accessible which allows to the reader various levels of expertises to easily include/understand the concepts and the notions which are exposed there, and this by maintaining rigorously the character's scientific base of contents. The clearness and the concision of information are also accentuated by many tables. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Controlled growth of 1D and 2D ZnO nanostructures on 4H-SiC using Au catalyst

A perfect control of nanostructure growth is a prerequisite for the development of electronic and optoelectronic device/systems. In this article, we demonstrate the growth of various ZnO-derived nanostructures, including well-ordered arrays of high aspect ratio single crystalline nanowires with preferred growth direction along the [0001] axis, nanowalls, and hybrid nanowire-nanowall structures. The growths of the various ZnO nanostructures have been carried out on SiC substrates in a horizontal furnace, using Au thin film as catalyst. From experimental observations, we have ascribed the growth mechanisms of the different ZnO nanostructures to be a combination of catalytic-assisted and non-catalytic-assisted vapor–liquid-solid (VLS) processes. We have also found that the different ZnO nanoarchitectures'' material evolution is governed by a Zn cluster drift effects on the SiC surface mainly driven by growth temperature. Au thin film thickness, growth time, and temperature are the parameters to optimize in order to obtain the different ZnO nanoarchitectures.     

Bacterial community dynamics in an anaerobic plug-flow type bioreactor treating swine manure

A plug-flow type anaerobic reactor consisting of eight sequential compartments was used to study shifts in a bacterial community adapted to degrade swine manure at 25 °C. The investigation was carried out during the first 6 months of reactor operation. The reactor successfully separated the hydrolysis/acidogenesis stage from the methanogenesis stage. Bacterial 16S rDNA- and rRNA-based fingerprints obtained through amplicon length heterogeneity PCR (LH-PCR) were analyzed with a view to characterizing the bacterial community structure and the metabolically active community, respectively. Multivariate statistical tools showed that the rDNA-based fingerprints described a more temporal than compartmentalized distribution of similar bacterial communities. By contrast, the rRNA-based multivariate analyses described a distribution that was linked more to reactor performance parameters, especially during short time periods. Diversity indices calculated from fingerprint data were used to assess overall diversity shifts. The decrease in rRNA-based diversity observed through the reactor compartments was greater than the decrease in rDNA-based diversity. This finding indicates that the analysis of metabolically active bacteria diversity was more discriminative than the analysis based on the mere presence of bacteria. The observed decrease in diversity suggests that the bacterial community became specialized in degrading less diversified substrates through the compartments. All these findings suggest that rRNA-based analyses are more appropriate for monitoring reactor performance.     

Development and validation of a food frequency questionnaire.

Regular diet monitoring requires a tool validated in the target population. A 73-item, semiquantitative, self-administered food frequency questionnaire (FFQ), was adapted in French and English from the Block National Cancer Institute Health Habits and History Questionnaire. The FFQ was used to capture usual long-term food consumption among adults living in Quebec. A representative sample of adults aged 18 to 82 (57% female) was recruited by random digit dialling in the Montreal region. Approximately 64% of recruits completed and returned the instrument by mail (n=248). The FFQ was validated in a subsample (n=94, 61% female) using four nonconsecutive food records (FRs). Median energy intakes (in kcal) for men and women, respectively, were FFQ (total sample) 2,112 and 1,823, FFQ (subsample) 2,137 and 1,752, and FR (subsample) 2,510 and 1,830. Spearman correlation analyses between FFQ and FR nutrients were positive (with r ranging from 0.32 for folate to 0.58 for saturated fatty acids) and statistically significant (p<0.001), with better results among women. On average, cross-classification of energy and 24 nutrients from the FFQ and means of four FRs placed 39% into identical quartiles and 78% into identical and contiguous quartiles, with only 4% frankly misclassified. These results suggest that the FFQ is a relatively valid instrument for determining usual diet in Quebec adults.     

Validation de la traduction de l'Inventaire d'épuisement professionnel de Maslach et Jackson.

Studied the psychometric properties of a French translation of the MBI. Ss were 260 day-care workers (mean age 29 yrs) in Study 1 and 123 nurses (mean age 38 yrs) in Study 2. Study 1 evaluated the internal consistency, factorial validity, temporal stability, and predictive validity of the MBI. Study 2 analyzed the convergent validity of the MBI in relation to measures of depression, anxiety, psychological stress, and other psychological symptoms. The distribution of low, average, and high professional-burnout scores in these 2 samples was compared to American norms. Several French-language instruments were used, including French versions of the MBI (C. Maslach and S. Jackson, 1981), the Beck Depression Inventory, the State–Trait Anxiety Inventory, and the Brief Symptom Inventory (L. R. Derogatis, 1983). (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of home practice in the thermal biofeedback treatment of migraine headache.

Examined the role of home practice of hand warming in the thermal biofeedback treatment of migraine headache. 17 female migraine sufferers were randomly assigned to 1 of the following conditions: thermal biofeedback with regular home practice (HP) or thermal biofeedback without home practice (NHP). Biofeedback treatment consisted of 12 training sessions over a 6-wk period, and all Ss completed 5 wks of headache monitoring before and after treatment. Results indicated that Ss in the HP condition experienced decreases in headache activity and medication intake that were both statistically and clinically significant compared with the NHP condition. None of the outcome measures revealed significant improvement in the NHP condition. Thus, regular HP appears to enhance the efficacy of biofeedback in the treatment of migraine. (PsycINFO Database Record (c) 2010 APA, all rights reserved)