Sébastien Bouchard

Cognitive-Behavioral Therapy for Insomnia: Comparison of Individual Therapy, Group Therapy, and Telephone Consultations.

Forty-five adults with primary insomnia received cognitive-behavioral therapy (CBT) implemented in a group therapy format, in individual face-to-face therapy or through brief individual telephone consultations. The results indicate that CBT was effective in improving sleep parameters with all 3 methods of treatment implementation, and there was no significant difference across methods of implementation. All 3 treatment modalities produced improvements in sleep that were maintained for 6 months after treatment completion. These results suggest that group therapy and telephone consultations represent cost-effective alternatives to individual therapy for the management of insomnia.

Planar waveguide concentrator used with a seasonal tracker

Solar concentrators offer good promise for reducing the cost of solar power. Planar waveguides equipped with a microlens slab have already been proposed as an excellent approach to produce medium to high concentration levels. Instead, we suggest the use of a cylindrical microlens array to get useful concentration without tracking during the day. To use only a seasonal tracking system and get the highest possible concentration, cylindrical microlenses are placed in the east-west orientation. Our new design has an acceptance angle in the north-south direction of ±9° and ±54° in the east-west axis. Simulation of our optimized system achieves a 4.6× average concentration level from 8:30 to 16:30 with a maximum of 8.1× and 80% optical efficiency. The low-cost advantage of waveguide-based solar concentrators could support their use in roof-mounted solar panels and eliminate the need for an expensive and heavy active tracker.

Sexual Attitudes and Activities in Women with Borderline Personality Disorder Involved in Romantic Relationships

Women with Borderline Personality Disorder (BPD) are prone to have sexual relationship difficulties and dysfunctional attitudes toward sexuality. A sample of 34 heterosexual couples composed of women meeting BPD criteria was compared to a sample of dating or married women from the general population. A short form of the Sexual Activities and Attitudes Questionnaire (SAAQ) was used to measure six types of sexual attitudes. Women diagnosed with BPD did not differ from controls on the frequency of three types of sexual activities in the last year but their subjective sexual experiences differed: they showed stronger negative attitudes, felt sexually pressured by their partners, and expressed ambivalence toward sexuality. Regression analyses suggest that anxious attachment mediates the association between BPD and feeling pressured to engage in sex.

Molecular Method for Detection of Total Coliforms in Drinking Water Samples

ABSTRACT This work demonstrates the ability of a bacterial concentration and recovery procedure combined with three different PCR assays targeting the lacZ, wecG, and 16S rRNA genes, respectively, to detect the presence of total coliforms in 100-ml samples of potable water (presence/absence test). PCR assays were first compared to the culture-based Colilert and MI agar methods to determine their ability to detect 147 coliform strains representing 76 species of Enterobacteriaceae encountered in fecal and environmental settings. Results showed that 86 (58.5%) and 109 (74.1%) strains yielded a positive signal with Colilert and MI agar methods, respectively, whereas the lacZ, wecG, and 16S rRNA PCR assays detected 133 (90.5%), 111 (75.5%), and 146 (99.3%) of the 147 total coliform strains tested. These assays were then assessed by testing 122 well water samples collected in the Québec City region of Canada. Results showed that 97 (79.5%) of the samples tested by culture-based methods and 95 (77.9%), 82 (67.2%), and 98 (80.3%) of samples tested using PCR-based methods contained total coliforms, respectively. Consequently, despite the high genetic variability of the total coliform group, this study demonstrated that it is possible to use molecular assays to detect total coliforms in potable water: the 16S rRNA molecular assay was shown to be as efficient as recommended culture-based methods. This assay might be used in combination with an Escherichia coli molecular assay to assess drinking water quality.

GRIN planar waveguide concentrator used with a single axis tracker

It is generally accepted that small to medium level concentrators could be used as cost-competitive replacements for tracked solar panels. The objective is to design a system that can reach a good level of sun concentration with only one sun-tracking axis and is cheap to fabricate. As the most critical parameter for all concentrator designs, optical efficiency needed improvement to reduce the cost of power produced by our system. By using a graded-index planar waveguide with an index profile similar to SELFOC fiber, the rays path can be controlled. Also, the concentrator can be fabricated in a single block, which reduces Fresnel reflections. Overall, the optical efficiency can be improved by as much as 33% compared to the same system made with a homogeneous waveguide. Furthermore, the ability to cost-effectively fabricate the concentrator by molding can be preserved, making it possible to reduce the cost of the solar power produced.

Detection of Escherichia coli colonies on confluent plates of chromogenic media used in membrane filtration.

MI agar (MI), Chromocult® Coliform agar ES (Chromocult), and DC with BCIG agar (DC) are chromogenic membrane filtration culture-based methods used to assess microbiological water quality. In this study, their ability to detect Escherichia coli colonies on confluent growth plates was determined by testing water samples containing increasing concentrations of a non-E. coli growing bacterium, Citrobacter youngae. Then, their ability to inhibit the growth of non-coliform bacteria was determined by simultaneously testing 603 well water samples. Results were compared with those obtained with mFC and Colilert® methods. Results showed that the E. coli count was difficult to determine on mFC, Chromocult and DC when non-E. coli colonies reached levels of 10(4)colony forming units (CFU)/100 mL. However, the E. coli count did not interfere with Colilert until non-E. coli colonies reached concentrations of 10(7)CFU/100 mL. No inhibition was observed with MI as E. coli colonies could be easily detected in the presence of at least 10(7)CFU/100 mL of C. youngae. Using well water samples, confluent growth plates were observed for 144, 177, and 185 of the 603 well water samples tested with the MI, Chromocult and DC methods, respectively. Among these confluent growth plates, E. coli colonies were not detected for 10, 20, and 31 water samples. However, they were detected by the mFC and/or Colilert methods. Thus, among the three methods tested, the MI method presented the lowest grow rate of atypic colonies and was the only one that presents no interference in the E. coli count.

Comparison of four β-glucuronidase and β-galactosidase-based commercial culture methods used to detect Escherichia coli and total coliforms in water.

The MI agar, Colilert(®), Chromocult coliform(®) agar, and DC with BCIG agar chromogenic culture-based methods used to assess microbiological quality of drinking water were compared in terms of their ubiquity, sensitivity, ease of use, growth of atypical colonies and affordability. For ubiquity, 129 total coliform (representing 76 species) and 19 Escherichia coli strains were tested. Then, 635 1-L well water samples were divided into 100 mL subsamples for testing by all four methods. Test results showed that 70.5, 52.7, 36.4, and 23.3% of the non-E. coli total coliform strains and 94.7, 94.7, 89.5, and 89.5% of the 19 E. coli strains yielded a positive signal with the four methods, respectively. They also yielded a total coliform positive signal for 66.5, 51.7, 64.9, and 55.0% and an E. coli positive signal for 16.1, 14.8, 17.3, and 13.4% of the 635 well water samples tested, respectively. Results showed that Colilert(®) is the most expensive method tested in terms of reactants, yet it is the easiest to use. Large numbers of atypical colonies were also often observed on Chromocult coliform(®) and DC with BCIG, thereby challenging the target microorganism count. Thus, the MI agar method seems to be the best option for the assessment of drinking water quality.

Couples’ Negative Interaction Behaviors and Borderline Personality Disorder

Borderline personality disorder (BPD) is a severe mental health problem predisposing to dysfunctional interaction behaviors and negative couple outcomes. This study aimed to assess, through direct observation, the quality of relationships of couples in which women were diagnosed with BPD. The sample consisted of 28 couples in which the woman had BPD, and 82 community couples. Couples’ interactions were coded using three scales—withdrawal/ avoidance, dominance, and criticism/attack/conflict—from the Global Couple Interaction Coding System. Couples in which the women had BPD evidenced significantly more negative behaviors, particularly dominance behaviors, than community couples. Moreover, in BPD couples, women adopted Criticism/Attack/Conflict behaviors more frequently than men.

Influence of the injection current on the degradation of white high-brightness light emitting diodes

Since high-power LEDs show great potential in reducing energy consumption worldwide, a great deal of research has been performed to understand their degradation rate. As reported in many publications, temperature is of critical importance so lifetests are mainly based on the internal temperature of the junction (Tj). A common testing method is to overdrive the LED with high current in order to cause self-heating. However, by doing so, it is assumed that current does not produce self-degradation. This topic is of great importance nowadays because of the recent development of LEDs used to increase operating current. We have conducted a lifetest on LEDs to isolate the influence of current by using a thermally-controlled heatsink to keep the same Tj for different driving currents. This paper presents the experimental setup with the associated protocol used in the experiment. We also present preliminary results obtained from two high-power white LEDs. These were stressed at currents ranging from 350 mA to 1000 mA and at temperatures ranging from 75°C to 150°C. To our knowledge, this type of measurement has not been reported in the literature. In the future, we would like to use a Weibull statistical model to study the combined effects of temperature and current on the degradation of LEDs.

Graded-index planar waveguide solar concentrator

Planar waveguides are useful to transport, concentrate and distribute light uniformly over large dimensions. Their capacity to collect and gather light efficiently over a large distance is interesting for many applications, like backlighting and solar concentration. For these reasons, the possibility of making them even more efficient could be of considerable interest for the community. The observation of the ray path inside a graded-index (GRIN) fiber inspired the development of a similar technology inside planar waveguides. In this Letter, we show that it has the potential to dramatically increase the efficiency of planar waveguide-based solar concentrators or backlighting using GRIN planar waveguides.