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The present study aimed to identify a way for educators to improve the accuracy of their praise and reprimand reflections to ultimately improve their ability to set, monitor, and evaluate their use of praise and reprimand. To do this, teachers’ natural use of praise and reprimand (in the absence of intervention) were compared with their perceived use. A 20-min direct observation was collected from 66 middle and high school teachers to obtain praise and reprimand rates. Following the observation, teachers reported their perceived use of praise and reprimand. A t test and analysis of variance (ANOVA) were used to determine differences between praise and reprimand types. Correlations were used to determine the relation between perceived and actual praise and reprimand use. Statistical results indicated teachers used more general praise (GP) than behavior-specific praise and more mild reprimand than any other reprimand type. Teachers’ actual and perceived use of GP were positively correlated, as were teachers’ actual and perceived use of mild, gestural, and total reprimand. Furthermore, teachers with a greater difference between their actual and perceived praise also had a greater difference between their actual and perceived reprimand use. Future research and implications of these findings are discussed.

Few studies have examined teachers’ natural use of praise and reprimand in the absence of training, possibly due to the challenges of live data collection. This study sought to determine the feasib...

We present in situ secondary ion mass spectrometry (SIMS) and electron microprobe analyses of coexisting garnet, omphacite, phengite, amphibole, and apatite, combined with pyrohydrolysis bulk-rock analyses to constrain the distribution, abundance, and behavior of halogens (F and Cl) in six MORB-like eclogites from the Raspas Complex (Southern Ecuador). In all cases concerning lattice-hosted halogens, F compatibility decreases from apatite (1.47–3.25 wt%), to amphibole (563–4727 μg/g), phengite (610–1822 μg/g), omphacite (6.5–54.1 μg/g), and garnet (1.7–8.9 μg/g). The relative compatibility of Cl in the assemblage is greatest for apatite (192–515 μg/g), followed by amphibole (0.64–82.7 μg/g), phengite (1.2–2.1 μg/g), omphacite (

Lithium and chlorine concentrations and isotopic compositions of well-characterized metasedimentary suites from the Schistes Lustres and Lago di Cignana (Western Alps) and the Catalina Schist (southern California, USA) were compared to determine Li and Cl behavior during prograde subduction-zone metamorphism. New data were obtained for Cl from both suites and for Li from the Western Alps. The Catalina Schist contains lawsonite-albite to amphibolite grade rocks recording peak temperatures of 200 to 750 °C and depths of 15 to 45 km, with the higher-grade units representing relatively warm subduction P-T paths. Bulk Cl concentrations decrease from ~100–500 μg/g to ~10–25 μg/g across metamorphic grades, largely due to Cl loss from chlorite and white mica, with most of this loss occurring at the lower grades. This loss mirrors the previously documented decreases in N, B, Cs, As, and Sb concentrations, with relatively little loss at higher metamorphic grade, and contrasts with the behavior of Li showing only modest loss and change in δ7Li values across all grades. Metapelitic rocks from the Western Alps representing a relatively “cool” geothermal gradient of ~8 °C/km, record peak temperatures of 350 to 550 °C and depths of up to 90 km. In this suite, both Cl and Li concentrations are uniform across grade, showing no obvious change in concentration. Lithium concentrations range to somewhat higher values compared to those previously measured in the Catalina Schist. Chlorine isotope compositions of the Schistes Lustres overlap with those measured in the Catalina Schist, whereas Li isotope compositions of the Schistes Lustres samples range to somewhat higher values than those from the Catalina Schist. Both suites show significant isotopic heterogeneity within single metamorphic grades and no systematic change in δ37Cl or δ7Li values with increasing grade. These heterogeneities are interpreted to be inherited from the protolith. Lithium isotope compositions correlate well with the chemical index of alteration (CIA), an observation also supporting minimal metamorphic alteration of the isotopic composition reflecting the protolith. These data demonstrate that, although some Cl is retained to great depths during subduction, most Cl is lost from metasedimentary rocks at shallow depths, similar behavior to that of B, Cs, As, and Sb. In contrast, Li loss is minimal across the full range of grade, more similar in behavior to Rb, Ba, and K.

Resume Cet article propose une revue de la litterature recente sur la notion de stress et de burnout scolaire. Issu du concept de burnout professionnel, le burnout scolaire, est une notion relativement recente. Apres avoir defini le concept initial de burnout professionnel, une analyse des liens entre le stress scolaire, en constante augmentation depuis plusieurs annees, et le developpement d’un burnout scolaire chez les eleves est presentee. Ensuite, de nombreux facteurs de risque predisposant au stress et au burnout scolaire, tels que les facteurs individuels et contextuels (scolaires et familiaux), sont discutes et mis en perspective avec certains facteurs de protection, dans une logique plus preventive que curative. Les differents outils d’evaluation du burnout scolaire seront egalement presentes. Enfin, du fait de la grande prevalence du burnout scolaire chez les eleves, certains pays etrangers ont developpe des programmes de prevention du bien-etre scolaire, afin de pallier les consequences deleteres du burnout sur la sante physique et mentale des enfants et adolescents scolarises.

Beaudoin, CM, Cox, Z, Dundore, T, Thomas, T, Kim, J, and Pillivant, D. Effect of bench press load knowledge on repetitions, rating of perceived exertion, and attentional focus. J Strength Cond Res 32(2): 514-519, 2018-Few studies have examined the role of the teleoanticipation during resistance training. The purpose of this study was to examine the effect of bench press (BP) load knowledge on repetitions completed, ratings of perceived exertion (RPEs), and attentional focus (% associative). Thirty-six recreationally active resistance-trained men (n = 25) and women (n = 11) participated in this study (age = 20.97 ± 1.87 years; ht = 174.12 ± 9.41 cm; and mass = 80.14 ± 14.03 kg). All subjects completed 3 testing sessions: (a) 1 repetition maximum (1RM) BP determination; (b) submaximal BP repetitions to fatigue known load (KL); and (c) submaximal BP repetitions to fatigue unknown load (UL). Known load and UL sessions were randomized and counterbalanced and both completed at 70% 1RM. An estimated weight ratio was computed using the subject's estimate of the UL weight relative to the KL weight. An independent samples t-test revealed no significant testing order difference for the estimated weight ratio. Two-way repeated-measures analysis of variances revealed no significant differences in the number of repetitions (p = 0.63), RPE (p = 0.18), or attentional focus (% associative) (p = 0.93) between the KL and UL conditions. Pearson correlations found a moderate positive association between KL repetitions completed and % associative focus when the UL was completed before the KL. Load knowledge did not influence the number of repetitions, RPE, or attentional focus while completing the BP. Further research examining the use of pacing strategies, RPE, and attentional focus during KL and UL conditions are warranted.

This article presents the results of a survey of student and faculty perspectives within a university-level instructional physical activity (PA) program. The results revealed that students enrolled in the courses primarily for enjoyment and to stay fit. A majority of students ranked the quality of instruction as excellent, were interested in new activity offerings such as SCUBA and training for road races, and would be likely or very likely to continue pursuing the activity in the future. Faculty responses included challenges in teaching instructional PA courses (e.g., varying skill levels, equipment access), the benefits of teaching including improved student skills and student enjoyment, and an interest in professional development opportunities. An ongoing evaluation of student and instructor perspectives within instructional PA programs is recommended and necessary, but responsiveness to this information is paramount for ensuring high-quality, engaging programs.

Background: Psychological stress – when an individual perceives that the environment exceeds their ability to meet the demands placed on them - is common in college students and exercise, and specifically instructional physical activity courses, is frequently cited as a one method of stress reduction. Objective: Determine any relationship between exercise empowerment and perceived life stress for those participating in instructional physical activity courses (IPAC). Methods: All undergraduate students (n = 3388) enrolled in IPAC in 15-week IPAC at a large university were surveyed on perceived life stress (PSS), empowerment in exercise (EES), and specific demographic variables. Results: 944 of 3388 enrolled students (Nov. 2015, April 2016) completed the survey. The data revealed GPA (p < 0.002), sex (p < 0.000), and EES (p < 0.001) showed differences for PSS. It was determined that EES, sex, and GPA predicted PSS differently for students according to their year in college. Conclusions: For freshman and seniors, sex and lower GPA were a stronger predictor of PSS with no mitigating effect of exercise empowerment. For sophomores and juniors the level of life stress was lower at higher levels of exercise empowerment. These findings support a complex relationship between exercise empowerment and life stress. While exercise is cited as a method for stress reduction the relationship between exercise empowerment and life stress for college-aged students is not as straightforward as it may seem.

We critically examine how two processing steps commonly applied in the preparation of cadmium telluride (CdTe)-based solar cells, i.e., the cadmium chloride treatment and the subsequent stepwise bromine/methanol wet etching process, impact the structural and optical properties of polycrystalline CdTe thin-films. In particular, drawing upon a conjuncture of photothermal deflection spectroscopy and spectroscopic ellipsometry experimental results, we determine the spectral dependence of the optical absorption coefficient, α(E), over the photon energy range from 1.1 to 2.0 eV for samples of rf sputtered (RFS) and close space sublimation (CSS) CdTe. The impact of these processing steps on shaping the grazing incidence x-ray diffraction pattern is also examined. We extend the analysis to devices through interpretation of the spectral dependence of the external quantum efficiency associated with two cadmium chloride treated CdTe-based solar cells. The cells are comparably prepared with the exception of the absorber, one by RFS and the other by CSS. Through the use of our results for the thin-film CdTe optical functions and a model for the solar cell multilayer structure, we simulate the resultant external quantum efficiency spectrum. Through a critical contrast with the corresponding solar cell acquired experimental results, we glean insights into the carrier trapping and recombination processes that occur within the two types of CdTe absorbers.

Background Return to work (RTW) is a major objective in the rehabilitation of individuals with severe traumatic brain injury (TBI). Implications for long-term occupational integration (beyond 5 years) have rarely been studied. Objective The objective was to assess long-term RTW and the associated factors after severe TBI. Material and methods Retrospective analysis of a cohort of individuals 16 to 60 years old admitted to hospital after severe TBI from 2005 to 2009 and followed prospectively. Medical and occupational data were collected from medical files and by systematic telephone interview to assess outcome at a minimum of 6 years post-trauma. Factors associated with RTW were investigated by multivariable regression analysis, estimating prevalence ratios (PRs) and 95% confidence intervals (CIs). A proportional hazards model was used to study RTW delay, estimating hazard ratios (HRs). Results Among the 91 individuals included (mean [SD] age 28.5 [11.3] years; 79% male), 63.7% returned to work after a mean of about 20 months, and 57.1% were still working at the time of the survey. Factors significantly associated with RTW on multivariable analysis were higher educational level (adjusted PR, 1.53; 95% CI, 1.15 to 2.03), absence of motor disability (adjusted PR, 1.82; 1.12 to 2.95) and behavioural disorder (adjusted PR, 1.26; 1.01 to 1.60), as well as disabled worker status (adjusted PR, 1.26; 1.01 to 1.60) (likelihood of the multivariate analysis model 53.1). Delayed RTW was associated with health insurance payments (adjusted HR, 0.40; 95% CI, 0.22 to 0.71), motor disability (adjusted HR, 0.34; 0.15 to 0.76), low educational level (adjusted HR, 2.20; 1.06 to 4.56) and moderate disability on the Extended Glasgow Outcome Scale (adjusted HR, 0.49; 0.27 to 0.91) (likelihood of the multivariate analysis model 335.5). Conclusion Individuals with the most severe TBI are able to RTW and remain in work. This study highlights the multiple determinants involved in RTW and the role of socioenvironmental factors.

An improved tool for operative vaginal delivery can reduce maternal and fetal trauma during the delivery and recovery processes. When a delivery cannot be completed naturally due to maternal exhaustion or fetal distress, physicians must perform an operative vaginal delivery (OVD), with forceps or a vacuum, or a Cesarean section (C-section). Although C-sections are more prevalent in the United States than OVDs, they require longer maternal hospital stays and recovery time and increase risk of maternal infection and fetal breathing problems [1]. In 2015, the American College of Obstetrics and Gynecology pushed to increase the number of OVDs to limit C-section associated delivery risks [2]. However, the current tools for OVD either have steep learning curves, are unable to be used for all fetal head presentations, or have associated maternal and fetal risks [3][4]. There is a need for an easy to use, safe, and reliable tool for operative vaginal delivery.

The bandedge optical properties of GaAsBi films, as thick as 470 nm, with Bi content varying from 0.7% Bi to 2.8% Bi grown by molecular beam epitaxy on GaAs substrates are measured by photoluminescence (PL) and photothermal deflection spectroscopy (PDS). The PDS spectra were fit with a modified Fernelius model which takes into account multiple reflections within the GaAsBi layer and GaAs substrate. Three undoped samples and two samples that are degenerately doped with silicon are studied. The undoped samples show a clear Urbach absorption edge with a composition dependent bandgap that decreases by 56 meV/% Bi and a composition independent Urbach slope parameter of 25 meV due to absorption by Bi cluster states near the valence band. The doped samples show a long absorption tail possibly due to absorption by gap states and free carriers in addition to a Burstein–Moss bandgap shift. PL of the undoped samples shows a lower energy emission peak due to defects not observed in the usually available thin samples (50 nm or less) grown under similar conditions.

We examine the dependence of the crystalline volume fraction on the mean crystallite size for hydrogenated nanocrystalline silicon based photovoltaic solar cells; this work builds upon an earlier study by Schmidt et al. (Mater. Res. Soc. Symp. Proc. 1536 (2013)). For each photovoltaic solar cell considered, the X-ray diffraction and Raman spectra are measured. Through the application of Scherrer’s equation, the X-ray diffraction results are used to determine the corresponding mean crystallite sizes. Through peak decomposition, the Raman results are used to estimate the corresponding crystalline volume fraction. Plotting the crystalline volume fraction as a function of the mean crystallite size, it is found that larger mean crystallite sizes tend to favor reduced crystalline volume fractions. The ability to randomly pack smaller crystallites with a greater packing fraction than their larger counterparts was suggested as a possible explanation for this observation.

We have performed an analysis on three hydrogenated nanocrystalline silicon (nc-Si:H) based solar cells. In order to determine the impact that impurities play in shaping the material properties, the XRD and Raman spectra corresponding to all three samples were measured. The XRD results, which displayed a number of crystalline silicon-based peaks, were used in order to approximate the mean crystallite sizes through Scherrer's equation. Through a peak decomposition process, the Raman results were used to estimate the corresponding crystalline volume fraction. It was noted that small crystallite sizes appear to favor larger crystalline volume fractions. This dependence seems to be related to the oxygen impurity concentration level within the intrinsic nc-Si:H layers.

Purpose – Little is known about health‐related advertising on university environments. Given the power of advertising and its potential effect on health behaviors, the purpose of this paper is to assess the health‐related advertisement environment and policies on university campuses.Design/methodology/approach – In total, ten geographically and ethnically diverse US university campuses that were trained in using the health‐related advertisement survey tool participated in the study. Inter‐rater reliability with data collectors at each university was established before data commencement began in Spring 2011. The survey tool assessed the types, locations, and prevalence of health‐related advertisements and messages (e.g. nutrition, alcohol, tobacco) on campus, and included both advertisements and messages related to any aspect of health by any sponsor. Current campus health‐related policies from each institution were collected as well.Findings – The largest proportion of advertisements on all campuses were ...

The use of an indwelling urinary catheter comes with associated risks. At a hospital in southern California, nurses on the acute rehabilitation unit suspected their patients were arriving from acute care with undiagnosed urinary tract infections (UTIs). This descriptive research study quantified the incidence of UTI on admission to a rehabilitation unit and correlations with catheter use. During the study period, 132 patients were admitted to acute rehabilitation from an acute care setting, and 123 met criteria to participate in the study. Among participants, 12% had a UTI upon admission. Questionnaires examined nursing attitudes toward appropriate urinary catheter use and proactive catheter removal. The data revealed that nurses want to be involved in decisions about urinary catheter use and that medical/surgical and rehabilitation nurses agree strongly about advocating for patients with indwelling urinary catheters.

Objective To examine the relationship between stores selling calorie-dense food near schools and student obesity risk, with the hypothesis that high availability predicts increased risk. Methods Mail surveys determined height, weight, and calorie-dense food consumption for 552 students at 11 Maine high schools. Driving distance from all food stores within 2 km (1.24 miles) of schools (or the closest store) was computed, and the impact of food store density and proximity to schools on student body mass index was determined by logistic regression. Results Ten schools had ≥ 1 store selling soda, and 8 schools had ≥1 fast-food restaurant within 1 km (0.62 miles). There were no significant relationships between the proximity or density of food stores around schools and student obesity risk. Students obtained sugar-sweetened beverages in many locations including at school. Conclusions and Implications Unhealthful food choices are ubiquitous. Consequently, stores selling these food items near schools have no significant affect on student obesity.

We conducted a case–control study to describe the clinical and epidemiologic characteristics of an outbreak of pandemic (H1N1) 2009 at a Canadian military cadet training center. We found that asthma and obesity confer greater risk for infection. Viral shedding was detected by PCR up to 18 days after symptom onset.

The optical absorption of GaAsN films grown by molecular beam epitaxy on GaAs substrates is measured using the mirage effect photothermal deflection spectroscopy (PDS). The PDS spectra were fitted with a modified Fernelius model, which takes into account multiple reflections within the GaAsN layer and GaAs substrate. This allowed the extraction of bandedge parameters for a series of GaAsN films with N content varying from 0.24% to 1.4% N. All films show a clear Urbach absorption edge with a composition-dependent bandgap consistent with literature and Urbach slope parameters roughly 3 times larger than GaAs values.

Objective To examine change in high school students' beverage consumption patterns pre- and post-intervention of reduced availability of sugar-sweetened beverages (SSB) and diet soda in school food venues. Design A prospective, quasi-experimental, nonrandomized study design. Setting Public high schools. Participants A convenience sample from control (n = 221) and intervention (n = 235) high schools. Intervention Schools aimed to reduce (n = 4) or not change (n = 3) availability of SSB and diet soda in food venues for 1 school year. Main Outcome Measures Subjects' beverage servings/day was determined from a food frequency questionnaire pre- and post-intervention. Analysis Two-by-two mixed analysis of variance model compared pre- to post-intervention servings/day between control and intervention subjects, stratified by gender. Results Consumption of SSB decreased in both intervention and control boys (F = 53.69, P P P Conclusion and Implications Reducing availability of SSB in schools did not result in a greater decrease in SSB consumption by intervention as compared to control subjects. The impact of reducing availability of SSB at school may be limited. A better understanding of beverage consumption patterns may be needed to determine the efficacy of school food policies on those youth susceptible to obesity.

The prevalence of childhood "overweight" and "at risk for overweight" has become a major public health concern. School food environments can affect key nutritional risk factors, especially in high schools where foods of poor nutrient value are pervasive in à la carte and vending programs. This study examines à la carte and vending programs in Maine public high schools at baseline and following implementation of low-fat (defined as itemsor=30% of total calories from fat), low-sugar (defined as itemsor=35% of sugar by weight), and portion-controlled (LFLS) guidelines.Four high schools implemented LFLS guidelines and 3 made no changes to à la carte and vending programs for a period of 1 school year.Findings revealed no significant change in food and beverage offerings in control schools. Whereas, in intervention schools, the proportion of items meeting the LFLS nutrient criteria increased from 32.8% to 81.8% in à la carte items, increased from 22.5% to 84.0% in snack vending, and increased from 48.0% to 98.9% in beverage vending from baseline to follow-up. However, these increases were mitigated when LFLS portion size criteria were applied.These findings demonstrate the successful implementation of LFLS guidelines similar to recommendations recently proposed by numerous organizations. School food service personnel were identified as key stakeholders in the successful implementation of the LFLS guidelines. Furthermore, these findings emphasize an important role the food and beverage industry will have in providing foods and beverages that meet proposed nutrient and portion guidelines.

Children need opportunities to have physical activity (PA). Using exergames could be a feasible and acceptable way to boost PA in middle schools. Our goal was to increase PA by 40 minutes per week and to determine how much time, if any, was spent in moderate-to-vigorous PA (MVPA).Eighty-four middle school youth were in a pilot study for 20 weeks: half in the Generation Fit (GenFit) intervention group and half in the control group. The GenFit group played the exergame for the first 10 weeks (Session 1), and the control group joined from 10 to 20 weeks (Session 2). The main outcome was exergaming time per student per week.Fifty-eight students completed the pilot after 26 youth at School C were excluded for administrative reasons. Of those remaining, 40 students at School A and 18 students at School B, the average age of the sample was 13.7 years (SD=0.6), and average body mass index percentile was close to 70. During Session 1, the average dance time per child was 49 minutes per week, versus 54 minutes per week in Session 2. Mean body mass index percentile decreased by 5.6 for children who participated in GenFit, compared with 0.2 for children in the control group. At end point, accelerometers showed over half of the dance time was spent in MVPA. Qualitative data showed that most children found the exergame acceptable.A dance exergame in middle schools offered opportunities for PA. About half of the exergame time was spent in MVPA. Exergames may be feasible and acceptable in middle schools to boost PA, and access could provide a way for schools to support the health of students.

CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme-1 with respective IC50 values of 22, 2, and 55 nM. We characterized the safety profile and toxicity of escalating doses of CGS 35601 over a 20-day period in chronically instrumented, unrestrained, conscious, male, spontaneously hypertensive rats (SHR). Once instrumented with an arterial catheter, the SHR were placed in metabolic cages allowing daily assessment of hemodynamics and blood sampling for biochemical and hematological measurements. After a 7-day stabilization period, the SHR were divided into 2 groups: Gr. 1, (n = 13 to 18) receiving CGS 35601 at 0.01, 0.1, 1 and 5 mg kg(-1) day(-1) (continuous i.a. infusion) for 5 consecutive days/dose, followed by a 5-day washout; and Gr. 2, (n = 10) receiving vehicle (saline). The highest dose of CGS 35601 dose-dependently reduced MABP from 156 +/- 4 up to 94 +/- 5 mm Hg, whereas heart rate, metabolic, electrolytic, and hematological profiles, growth, diuresis, and renal activity were unaffected, and no hepatic or liver toxicities were observed. These results suggest that this novel triple VPI presents no safety concerns at this stage and may become of interest for the treatment of hypertension and other cardiovascular disorders. Long-term chronic experiments are needed to assess possible angioedema and increases in vascular permeability.

We study the effects of multilevel mixing of the 1s and 2s states of the E1-HH1 and E2-HH1 excitons in the emission spectra of an undoped quantum well. This is done by investigating the E1-HH1 exciton emission spectra in the presence of an intense CO/sub 2/ laser near resonance with the transition between El and E2. Our results show that, depending on the frequency of the CO/sub 2/ laser, these spectra are quenched peculiarly. We explain these phenomena based on the frequency dependence of the mixing configurations of the exciton states and infrared enhancement of the nonradiative decay rates of E1-HH1 excitons. We also study the effect of the nonparabolicity of the hole subband (HH1) in the infrared mixing of the E1-HH1 and E2-HH1 excitons.

TI he industrial revolution represents a tremendous turning point in human history. As such, it has generated a vast collection of studies on its nature, causes, and consequences. These run the gamut from grand theories on industrialization's diffusion to detailed local studies of its varied impacts (1). This article strives to bring some order to this assortment by grouping the literature into four categories: definition and characteristics; context and causation; impacts and scope; and global implications. The first three of these categories focus primarily upon the Western experience because it has served as an example for both those seeking to copy it and scholars who have studied industrialization outside the West

The low temperature optical absorption spectra of fully coherent strain-compensated InAsxP1−x/GayIn1−yP (0.15⩽x⩽0.27; 0.09⩽y⩽0.13) multilayers grown on InP(001) by organometallic vapor phase epitaxy were measured using a Fourier transform infrared interferometer. All spectra show well-resolved excitonic transitions. The analysis with a solution to the Schrodinger equation in the envelope function formalism using the Bastard–Marzin model allows to determine accurately that the strained conduction band offset δEc equals (776±4)x meV, or 77%±2% of the total strained band gap difference. The heterojunction alignment is of type I for both heavy- and light-hole bands but the light-hole confinement is very shallow. The heavy- and light-hole exciton binding energies obtained from the analysis are ≃9 and 6–7 meV, respectively.

Objective: To develop a self-report instrument to assess diagnostic criteria and associated features of pathological gambling in order to learn more about the characteristics of individuals who seek treatment for gambling problems in a Canadian setting. Method: Fifty-seven adults seeking treatment for gambling problems at the Addictions Foundation of Manitoba were assessed. Results: There was substantial variation in the endorsement of Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) symptoms. Lying to family members or friends and “chasing” previous gambling losses were frequently reported, while more serious consequences (for example, relationship breakup, job losses) were less frequent. DSM-IV ratings were correlated (r = 0.59) with the South Oaks Gambling Screen. Many individuals reported gambling as a way to alleviate dysphoric mood, and 30% reported receiving mental health services in the past. Approximately 50% reported suicidal ideation, although recent suicide attempts were not common. Conclusion: These preliminary results of Canadian adults seeking treatment for gambling problems suggest a somewhat different profile from many United States studies, which often rely on older male pathological gamblers. More systematic investigation of the presence of major depression and other psychiatric disorders is warranted. Consistent with demographic data collected at the Addictions Foundation of Manitoba, it appears that video lottery terminals play a major role in the type of problem gambling experience seen in Canadian settings.

Two databases of complex dielectric constants, for InGaAs and InAlAs, near-lattice matched to InP, and around temperatures of 500°C, have been fit using a transfer function model with temperature and composition-dependent coefficients. The parameters of the model are determined with a least-squares algorithm with recursive “whitening” of the error, which shows fast convergence to a near-optimal solution, even when handling a large number of parameters. The model can be inverted by a simple algorithm to retrieve temperature and composition information from optical measurements obtained by spectroscopic ellipsometry. The level of accuracy achieved makes this method adequate for temperature, composition, and thickness determination during MBE growth.

The α-particle energy loss method (AEL) has been implemented in situ to monitor film thickness and composition during growth of GaAs, InP and LaF 3 based materials by molecular beam epitaxy (MBE). In the AEL method, a 228 Th source is used to recoil implant a 5 mm diameter region of the surface of the wafers with the α-emitter daughter isotope 224 Ra prior to growth. The implanted nuclei decay with a half life of 3.7 days through a sequence of daughters which emit alpha particles at different energies. Deposition on the surface causes the emission lines to be shifted to lower energies due to energy loss in the film. For substrates marked with a low activity (∼ 30 kBq; similar to activity of smoke detectors) we are able to measure film thickness with ± 6 nm uncertainty and growth rate with ± 0.01 nm/s uncertainty in real time. By measuring the relative growth rates of the different materials, AEL also allows us to infer the composition of a ternary laver film as well as the sticking coefficients rates directly at different growth temperatures.

Precise control of layer thickness and alloy compositions are very critical for the successful growth of vertical cavity surface emitting lasers (VCSEL) and resonant cavity enhanced photodetectors (RCEPD). In traditional MBE, the growth of these devices requires extensive calibrations. Recently, spectroscopic ellipsometry (SE) was shown to be an accurate method for determining the composition and thicknesses of III–V semiconductor layers in situ during growth. This paper reports the growth of AlAs/GaAs/InGaAs RCEPDs using SE control with no a priori calibration curves. The experimentally measured cavity resonance of the reflectivity spectrum and the photoresponse peak of the fabricated photodiode lie within 3 nm of the target design value of 990 nm. These results show that feedback control during MBE allows quicker and more reproducible growth of RCEPDs with precise control of layer thickness and alloy composition than calibration-based control.

The temperature dependence of the diffusion of lead in GaAs is determined by measuring the modification to the energy spectrum of emitted alpha particles from the decay chain of implanted 212Pb atoms. Diffusion rates are measured for temperatures up to 900 °C. Higher rates are observed for the diffusion in silicon-doped GaAs than in semi-insulating GaAs. An upper limit for the diffusion of radium in GaAs is similarly obtained from the decay of the 224Ra isotope. Implications for the use of implanted alpha sources for thickness monitoring during epitaxial film growth by the alpha-particle energy loss method are discussed.

Management of the limited fresh water resources on small oceanic islands has become critical with increasing population and development in coastal areas. Canals, dredged for waterfront property and boat access, penetrate water-bearing material and accelerate the natural discharge from fresh water lenses. Big Pine Key, located in the southern portion of the Florida Keys, is a heterogeneous, two-layer island with several canal networks. The island is approximately 3 km wide and 10 km long. The upper hydros-tratigraphic unit (Miami Oolite Limestone) has a hydraulic conductivity of 100 meters per day (m/day). The lower unit (Key Largo Limestone) has a hydraulic conductivity of 1200 m/day. To quantify the effects of canals on the fresh water lens of Big Pine Key, a numerical model was developed using the Dupuit and Ghyben-Herzberg assumptions. The thickness of the fresh water lens is sensitive to the location of the boundary between the upper and lower hydros-tratigraphic layers. A simulation of present-day Big Pine Key, including canals, compared with predevel-opment conditions shows that the total volume of the lens has decreased by 20% in response to the dredging of canals. As dredging of canals will certainly continue in the future, the numerical model was also used to investigate the types of canals that are most detrimental to a fresh water lens. For an island 3 km wide and 10 km long, a canal that penetrates 2 km lengthwise into the island reduces the volume of the fresh water lens by 6.5%. For the same island dimensions, a canal that penetrates 2 km through the mid-section of the island reduces the volume of the fresh water lens by 7.1 %. Several short canals, with a combined total length of 2 km decrease the volume of the fresh water lens by 4.0 %. The deeper the penetration of the canal into the lens, the greater the influence of the canal. Therefore, several short canals are preferred over one long canal because shorter canals have less of an effect on the total volume of the fresh water lens. Canals also focus ground water discharge. The three configurations of 2000 m long canals each discharge 13 to 15% of the total recharge to the island.

Using the pump-probe technique, we have observed time-resolved differential reflection in InAsxP1−x/InP (x⩽0.35) strained-multiple-quantum wells. The experimental results show that barrier height, interface roughness and well width influence strongly the differential reflection dynamics. For samples with the same interface quality and almost the same well width, the delay time of the differential reflection decreases with increasing barrier height, while for the sample with rough interface and narrower wells, the delay time of the differential reflection is much slower, although it has a larger barrier height. To understand the experimental results, we have performed a simulation study of temporal and spatial evolutions of photoexcited carriers in the samples, and the influence of various physics processes on the photoexcited carrier dynamics has been discussed. From the calculated and the measured results, we conclude that carrier diffusion in the cap layer and the barriers plays a dominant role in deter...