Grace (Canada)

Neste trabalho, apresentamos os flocos de neve e suas características únicas. Com o auxílio do software GeoGebra, esses flocos podem ser usados como uma ferramenta valiosa no ensino de transformações geométricas, tais como rotação, translação, reflexão e homotetia. Para isso, elaboramos propostas de atividades destinadas aos estudantes do 7o ano e 8o ano do Ensino Fundamental.

BackgroundCardiovascular diseases (CVD) are the leading causes of death in the world, mainly occurring in low-and-middle income countries. The aim of this study was to estimate the prevalence of hypertension and other cardiovascular risk factors among university students at a National Polytechnic Institute in Côte d’Ivoire.MethodsA cross-sectional study was conducted among students of the National Polytechnic Institute of Côte d’Ivoire. Sample was selected using a non-probabilistic convenient sampling method. Anthropometric measurements, blood pressure and capillary blood glucose were measured. A logistic regression model allowed to determine factors associated with hypertension.ResultsA total of 2,030 students, 79.7% males and 20.3% females, with a median age of 20 years (IQR = [19–22]) participated in the study. On hypertension knowledge, 96.9% (n = 1,968) of students reported having heard of hypertension; salty foods were reported by more than a third as a cause of hypertension (n = 734; 37.3%), while 114 (5.8%) and 157 (8.0%) selected tobacco and alcohol as causes of hypertension, respectively. The overall prevalence of hypertension was 6.0%, higher in males (6.8%) compared to females (2.7%) (p < 0.001). As for CVD risk factors, 148 (7.3%) were overweight or obese; 44.0% of males and 36.6% of females reported alcohol consumption. In multivariate analysis, being a female (OR = 4.16; CI 95% = [1.96–9.09]; p<0.001), being 25 years old and older (OR = 3.34; CI 95% = [2.01–5.55]; p = 0.001), tobacco use (OR = 2.65; CI 95% = [1.41–4.96]; p = 0.002), being overweight or obese (OR = 3.75; CI 95% = [2.13–6.59]; p<0,001) and having abnormal waist circumference (OR = 6.24; CI 95% = [1.99–19.51]; p = 0.002) were significantly associated with high blood pressure.ConclusionCVD risk factors are prominent among young adults in Côte d’Ivoire. Appropriate behavioural health interventions promoting a healthy lifestyle for young adults should be urgently implemented for CVD burden reduction.

In most single-photon defect emitters, such as those in SiC and diamond, interaction with low-energy acoustic phonons determines the temperature dependence of the decoherence rate and the resulting broadening of the ZPL with the temperature obeys a power law. GaN hosts bright and stable single-photon emitters in the 600 nm to 700 nm wavelength range with strong ZPLs even at room temperature. In this work, we study the temperature dependence of the ZPL spectra of GaN SPEs integrated with solid immersion lenses with the goal of understanding the relevant decoherence mechanisms. At temperatures below ~50 K, the ZPL lineshape is found to be Gaussian and the ZPL linewidth is temperature independent and dominated by spectral diffusion. Above ~50 K, the linewidth increases monotonically with the temperature and the lineshape evolves into a Lorentzian. Quite remarkably, the temperature dependence of the linewidth does not follow a power law. We propose a model in which decoherence caused by absorption/emission of optical phonons in an elastic Raman process determines the temperature dependence of the lineshape and the linewidth. Our model explains the temperature dependence of the ZPL linewidth and lineshape in the entire 10 K to 270 K temperature range explored in this work. The ~19 meV optical phonon energy extracted by fitting the model to the data matches remarkably well the ~18 meV zone center energy of the lowest optical phonon band (E2(low)) in GaN. Our work sheds light on the mechanisms responsible for linewidth broadening in GaN SPEs. Since a low energy optical phonon band (E2(low)) is a feature of most group III-V nitrides with a wurtzite crystal structure, including hBN and AlN, we expect our proposed mechanism to play an important role in defect emitters in these materials as well.

Point defects in crystalline materials often occur in multiple charge states. Although many experimental methods to study and explore point defects are available, techniques to explore the non-equilibrium dynamics of the charge states of these defects at ultrafast (sub-nanosecond) time scales have not been discussed before. We present results from ultrafast optical-pump supercontinuum-probe spectroscopy measurements on $\beta$-Ga$_2$O$_3$. The study of point defects in $\beta$-Ga$_2$O$_3$ is essential for its establishment as a material platform for high-power electronics and deep-UV optoelectronics. Use of a supercontinuum probe allows us to obtain the time-resolved absorption spectra of material defects under non-equilibrium conditions with picosecond time resolution. The probe absorption spectra shows defect absorption peaks at two energies, $\sim$2.2 eV and $\sim$1.63 eV, within the 1.3-2.5 eV probe energy bandwidth. The strength of the absorption associated with each peak is time-dependent and the spectral weight shifts from the lower energy peak to the higher energy peak with pump-probe delay. Further, maximum defect absorption is seen for probe polarized along the crystal c-axis. The time-dependent probe absorption spectra and the observed dynamics for all probe wavelengths at all pump-probe delays can be fit with a set of rate equations for a single multi-level defect. Based on first-principles calculations within hybrid density functional theory we attribute the observed absorption features to optical transitions from the valence band to different charge states of Gallium vacancies. Our results demonstrate that broadband ultrafast supercontinuum spectroscopy can be a useful tool to explore charge states of defects and defect dynamics in semiconductors.

To examine: (1) the rate of clinical events precluding cardiac rehabilitation (CR) continuation, (2) CR attendance by component in those without events, and (3) the association between disease severity (eg, tobacco use, diabetes, and depression) and component attendance (eg, exercise, diet, stress management, and tobacco cessation). Retrospective analysis of electronic records of the CR program in London, Ontario, from 1999 to 2017. Patients in the supervised program are offered exercise sessions 2 times/wk with a minimum of 48 prescribed sessions tailored to patient need. Patients attending ≥1 session without major factors that would limit their exercise ability were included. Intervening events were recorded, as was component attendance. Of 5508 enrolled, supervised patients, 3696 did not have a condition that could preclude exercise. Of those enrolled, one-sixth (n = 912) had an intervening event; these patients were less likely to work, more likely to have medical risk factors, had more severe angina and depression, and lower functional capacity. The remaining cohort attended a mean of 26.5 ± 21.3 sessions overall (median = 27; 19% attending ≥48 sessions), including 20.5 ± 17.4 exercise sessions (median = 21). After exercise, the most common components attended were individual dietary and psychological counseling. Patients with more severe angina and depressive symptoms as well as tobacco users attended significantly fewer total sessions, but more of some specific components. In one-sixth of patients, CR attendance and completion are impacted by clinical factors beyond their control. Many patients are taking advantage of components specific to their risk factors, buttressing the value of individually tailored, menu-based programming.

In her article the author presents the opinions of students concerning their professional&#13;\ncareer opportunities.&#13;\nYoung people on the threshold of their professional careers have to face the necessity of&#13;\nnegotiating over their jobs - a task particularly difficult in the situation of a crisis on the labour&#13;\nmarket. Those negotiations are understood as a configuration of specific talks held by&#13;\ntwo sides:&#13;\n- an employer, purchasing particular goods such as labour,&#13;\n— an employee, offering his abilities and devotion.&#13;\nTheir mutual relations dictate supply and demand for labour, which undergoes business&#13;\ncycles.&#13;\nIn order to explain this market process, the author constructed and conducted two-staged&#13;\nresearch. In the first stage, a sample of students was presented with a description of the labour&#13;\nmarket and asked to discuss career opportunities on the described market. At the next&#13;\nstage they were requested to describe their preparations for undertaking professional activities&#13;\nand focused mainly on the strengths and weaknesses of actors on the labour market.&#13;\nThe analysis of the research results in the following article may help to understand fears and&#13;\nhopes of young people and to prepare an effective program which could facilitate finding a place&#13;\non the increasingly demending labour market.

The study aimed to gauge the perceptions of Canadians toward genital warts, related health behaviors, and treatment preferences. An online survey supported by an unrestricted grant from Graceway Canada was conducted in February 2011 by Leger Marketing. It included 9 demographic questions and 17 questions relating to genital wart perception (2 multiple-choice, 15 four-point rating from strongly agree to strongly disagree). The survey was completed by 1520 Canadian adults aged 18 to older than 75 years, of whom 52% (786/1520) were female. Fifty-two percent of respondents stated that they would monitor an unrecognized spot on their genitals, and only seek medical assistance if it did not go away. Only 43% (652/1520) said that they would stop having sex until the spots were gone. Although only 10% (158/1520) of respondents stated that they would not inform their partner, this was much higher among men (14%, 103/734) than women (7%, 55/786), with p ≤ .01. Concerns of being judged by friends/family were high (44%, 669/1520), especially among younger (18-34 y) Canadians (60%), with p ≤ .05. Regarding prevention, 32% (493/1520) of respondents believed that monogamy would protect against genital warts and 25% (373/1520) believed they are not at risk if they use a condom. Treatment preference was in favor of a cream rather than an "invasive" treatment (58%, 886/1520), particularly among younger (67%, 283/425, p ≤ .05) and male respondents (63%, 464/734, p ≤ .01). Sixty percent (921/1520) would worry that genital warts could not be resolved; and 44% (668/1520), that they would recur. Among Canadians, genital warts were associated with a fair degree of social stigma and potential negative impact on their psyche, especially for younger Canadians.

Graphene nanoribbon (GNR) field-effect transistors (FETs) with widths down to 12 nm have been fabricated by electron beam lithography using a wafer-scale chemical vapor deposition (CVD) process to form the graphene. The GNR FETs show drain-current modulation of approximately 10 at 300 K, increasing to nearly 106 at 4 K. The strong temperature dependence of the minimum current indicates the opening of a bandgap for CVD-grown GNR-FETs. The extracted bandgap is estimated to be around 0.1 eV by differential conductance methods. This work highlights the development of CVD-grown large-area graphene and demonstrates the opening of a bandgap in nanoribbon transistors.