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In formerly glaciated permafrost regions, extensive areas are still underlain by a considerable amount of glacier ice buried by glacigenic sediments. It is expected that large parts of glacier ice buried in the permafrost will melt in the near future, although the intensity and timing will depend on local terrain conditions and the magnitude and rate of future climate trends in different Arctic regions. The impact of these ice bodies on landscape evolution remains uncertain since the extent and volume of undisturbed relict glacier ice are unknown. These remnants of glacier ice buried and preserved in the permafrost contribute to the high spatial variability in ground ice condition of these landscapes, leading to the formation of lakes with diverse origins and morphometric and limnological properties. This study focuses on thermokarst lake initiation and development in response to varying ground ice conditions in a glacial valley on Bylot Island (Nunavut). We studied a lake-rich area using lake sediment cores, detailed bathymetric data, remotely sensed data and observations of buried glacier ice exposures. Our results suggest that initiation of thermokarst lakes in the valley was triggered from the melting of either buried glacier ice or intrasedimental ice and ice wedges. Over time, all lakes enlarged through thermal and mechanical shoreline erosion, as well as vertically through thaw consolidation and subsidence. Some of them coalesced with neighbouring water bodies to develop larger lakes. These glacial thermokarst lakes formed in buried glacier ice now evolve as “classic” thermokarst lakes that expand in area and volume as a result of the melting of intrasedimental ground ice in the surrounding material and the underlying glaciofluvial and till material. It is expected that the deepening of thaw bulbs (taliks) and the enlargement of Arctic lakes in response to global warming will reach undisturbed buried glacier ice where it is still present, which in turn will substantially alter lake bathymetry, geochemistry and greenhouse gas emissions from Arctic lowlands.

Over the past decades, observations of buried glacier ice exposed in coastal bluffs and headwalls of retrogressive thaw slumps of the Arctic have indicated that considerable amounts of late Pleistocene glacier ice survived the deglaciation and are still preserved in permafrost. In exposures, relict glacier ice and intrasedimental ice often coexist and look alike but their genesis is strikingly different. This paper aims to present a detailed description and infer the origin of a massive ice body preserved in the permafrost of Bylot Island (Nunavut). The massive ice exposure and core samples were described according to the cryostratigraphic approach, combining the analysis of permafrost cryofacies and cryostructures, ice crystallography, stable O-H isotopes and cation contents. The ice was clear to whitish in appearance with large crystals (cm) and small gas inclusions (mm) at crystal intersections, similar to observations of englacial ice facies commonly found on contemporary glaciers and ice sheets. However, the δ18O composition (-34.0±0.4 ‰) of the massive ice was markedly lower than contemporary glacier ice and was consistent with the late Pleistocene age ice in the Barnes Ice Cap. This ice predates the aggradation of the surrounding permafrost and can be used as an archive to infer palaeo-environmental conditions at the study site. As most of the glaciated Arctic landscapes are still strongly determined by their glacial legacy, the melting of these large ice bodies could lead to extensive slope failures and settlement of the ground surface, with significant impact on permafrost geosystem landscape dynamics, terrestrial and aquatic ecosystems and infrastructure.

A miniature atmospheric pressure glow discharge plasma torch was used to detach cells from a polystyrene Petri dish. The detached cells were successfully transplanted to a second dish and a proliferation assay showed the transplanted cells continued to grow. Propidium iodide diffused into the cells, suggesting that the cell membrane had been permeabilized, yet the cells remained viable 24?h after treatment. In separate experiments, hydrophobic, bacteriological grade polystyrene Petri dishes were functionalized. The plasma treatment reduced the contact angle from 93° to 35°, and promoted cell adhesion. Two different torch nozzles, 500?µm and 150?µm in internal diameter, were used in the surface functionalization experiments. The width of the tracks functionalized by the torch, as visualized by cell adhesion, was approximately twice the inside diameter of the nozzle. These results indicate that the miniature plasma torch could be used in biological micropatterning, as it does not use chemicals like the present photolithographic techniques. Due to its small size and manouvrability, the torch also has the ability to pattern complex 3D surfaces. [ABSTRACT FROM AUTHOR]

The performance of a nanosecond repetitively pulsed discharge for CH4 reforming is studied at atmospheric pressure for temperatures ranging from 300 to 700 K. The high-voltage pulser used is capable of producing a voltage pulse with an amplitude of 14 kV and a duration of 40 ns at a repetition frequency of 10 kHz. The discharge energy per pulse is varied in a range from 462 J to 2.47 mJ. The rotational temperature is estimated by fitting synthetic to experimental spectra. Experiments at pulsing frequency of 1 kHz led to temperature profiles that remain unchanged along the axial direction of the reactor. For pulse frequencies between 2–10 kHz, the average temperature of the filament rises from 507 to 777 K. Emission from C2(A–X) is compared to emission from CH(A–X) along the reactor axis and with respect to the energy input. It is found that as the energy input increases, so does the emission from C2(A–X), turning the discharges green rather than blue. Results from CH4 conversion show that the inlet gas temperature has negligible effect on reforming performance. Higher values of energy per pulse improve conversion and energy efficiency. However, increasing the pulse frequency leads to the best performance enhancement with a maximum slope of 0.53% and 0.24% per kJ · mol−1 for conversion and energy efficiency, respectively. The maximum conversion and energy efficiencies were 68.2% and 25.6%, respectively, measured in a CH4–air mixture. [ABSTRACT FROM AUTHOR]

The operation of a nanosecond repetitively pulsed discharge for partial oxidation of CH4 is characterized at atmospheric pressure and room temperature. Two regimes are observed: diffuse and filamentary. The first is a low power regime, characterized by low rotational temperatures around 400 K. The second is much more energetic with rotational temperatures close to 600 K. Both have vibrational temperatures of at least 10 times their rotational temperatures. The average electron number density was determined to be and cm−3, respectively, showing an increase in the ionization fraction in the more powerful filamentary regime. Results of CH4 conversion to H2, CO, CO2 and C2H6 are presented for the filamentary regime, while the diffuse regime shows no measurable conversion ability. As expected, oxidative mixtures show higher conversion ability than pure CH4. A maximum conversion efficiency of 26.3% and a maximum energy efficiency of 19.7% were reached for the oxidative mixtures. [ABSTRACT FROM AUTHOR]

Nanofluids—engineered colloidal suspensions in base liquids—have captivated the interest of researchers over the last two decades for various existing as well as emerging technological applications. The main impetus for the synthesis of such novel nanocomposite liquids is the potential to alter properties of the base liquid, such as its viscosity, thermal conductivity, and surface tension, and to introduce specific optical and magnetic properties. Numerous studies suggest trends and explanations for the effects associated with the addition of nanoparticles, and that deviation from the base liquid properties are dependent on nanoparticle concentration. However, there remains a certain ambiguity in the available literature. The wetting behavior and surface tension of nanofluids are particular examples where highly conflicting results exist. In this study, we used multi-walled carbon nanotubes (MWCNTs) functionalized by plasma treatment and dispersed in reverse osmosis water and 99% anhydrous ethanol. Our observations reveal that the surface tension and wetting behavior of the stable aqueous and ethanol-based nanofluids containing plasma functionalized MWCNTs are unaffected by the MWCNT loading up to 120 (0.012) and ∼210 (0.021) ppm (vol%), respectively. The ethanol-based MWCNT nanofluids allowed us to extend the study to higher loadings, and a linear increase of the surface tension past ∼200 ppm was observed. Conversely, nanofluids containing non-functionalized or surfactant-stabilized MWCNTs show drastically different contact angle values when compared to the base liquids even at very low concentrations (less than 100 ppm). We demonstrate that the stability of nanofluid and method of stabilization are crucial parameters in determining the wetting behavior of nanofluids. [ABSTRACT FROM AUTHOR]

This paper discusses the development and characteristics of a distributed nanosecond-pulsed glow-like discharge plasma in air at atmospheric pressure. The produced pulse is of 6.4 kV with duration at half maximum of less than 80 ns, and an average pulse repetition frequency of 150 Hz. The discharge operates in air in a concentric electrode configuration. Spectroscopic studies are presented in order to assess the thermal characteristics of the plasma as well as its spatial characteristics. Electrical diagnostics are presented along with time averaged ICCD imaging of the radially distributed plasma. Although variations occur, it is found that the plasma has uniform vibrational and rotational temperatures across the inter electrode gap illustrating a high degree of disequilibrium in the plasma. Band head intensity analysis proves the existence of a negative glow in the near cathode region. Finally, the sensitivity of individual vibrational bands to vibrational and rotational temperatures is presented as a means to most accurately evaluate the uncertainty of spectrally determined temperatures. [ABSTRACT FROM AUTHOR]

Titanium nitride has long been used for its favourable mechanical and chemical properties and it has been demonstrated that monocrystallinity in thin films enhances these properties. While the synthesis of monocrystalline thin films is well documented, common synthesis processes for titanium nitride nanoparticles yield only polycrystalline, spherically shaped powders. The process presented here allows for the synthesis of monocrystalline, cube-shaped nanoparticles by means of a dual plasma process. Pulsed electric arc erosion of a Ti cathode in a N-rich atmosphere produced by a radio-frequency discharge is used for the synthesis of the TiN nanoparticles. Electron microscopy revealed the cubic morphology of the synthesized powders and electron diffraction patterning confirmed the crystalline structure of the TiN nanoparticles. [ABSTRACT FROM AUTHOR]

LGBT2Q+ (lesbian, gay, bisexual, transgender, Two-Spirit, queer, plus) Canadians face minority stressors that lead to higher mental health inequalities such as worse self-reported mental health and increased risk of mental health issues when compared to their heterosexual/straight and cisgender counterparts. However, there are within-group (intracategorical) differences within a community as large as LGBT2Q+ peoples. Guided by the Andersen Model of Healthcare Utilization, we sought to explore intracategorical differences in LGBT2Q+ Canadian predisposing, enabling, and need factors in mental health service utilization within the past year. Using data from the 2020 LGBT2Q+ Health Survey (N = 1542), modified Poisson logistic regression found that more polysexual respondents and trans/gender-diverse respondents were more likely to have utilized mental health services within the past year than their gay, lesbian, and cis male counterparts. As well, compared to White respondents, Indigenous respondents were more likely to have utilized mental health services, while other racialized respondents were associated with less utilization. Backwards elimination of Andersen model of healthcare utilization factors predicting mental health service utilization retained two predisposing factors (ethnoracial groups and gender modality) and two need factors (self-reporting living with a mood disorder and self-reporting living with an anxiety disorder). Results suggest that polysexual, trans and gender-diverse, and racialized LGBT2Q+ peoples have an increased need for mental health services due to increased specific minority stressors that cisgender, White, monosexual peoples do not face. Implications for healthcare providers are discussed on how to improve service provision to LGBT2Q+ peoples., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: Mental health disparities in sexual orientation and/or gender identity and/or expression (SOGIE) minority groups are well-documented, with research consistently showing higher levels of suicidality, even in Canada, considered one of the world's most accepting countries of SOGIE minority groups. Adverse outcomes in these groups are often framed using minority stress theory, with social support frequently studied as an integral buffer to these outcomes. This analysis explores facets of minority stress and social support associated with past-year suicidal ideation and suicide attempts. Methods: A cross-sectional internet survey of SOGIE diverse people in Canada ( n  = 1542) was conducted. Binary logistic regression calculated bivariate and multivariate factors associated with past-year suicidal ideation and suicide attempts. Backward elimination (retaining sociodemographic factors and self-rated mental health) identified salient minority stress and social support (provisions) factors. Results: Over half (56.72%) of participants had ever thought of dying by suicide, with 24.84% having attempted suicide. During the past year, 26.80% had thought of dying by suicide, with 5.32% having attempted suicide. Victimization events, and guidance (e.g., someone to talk to about important decisions) and attachment (e.g., close relationships providing emotional security) social provision subscales remained salient after backward elimination procedures. Conclusion: Our findings emphasize that a fulsome, multilevel approach considering structural, community, and individual strategies to address overt discrimination, integrating social connections and guidance, is necessary to prevent dying by suicide.

Multiwalled carbon nanotubes find applications in many fields due to their extraordinary properties. However, depending on their synthesis method, they show no or a poor response to the presence of a magnetic field. This limits their usability in magnetic applications. In this study, the maximum induced magnetization of multiwalled carbon nanotubes was increased by deposition of magnetic nanoparticles, which were produced by nanosecond pulsed laser deposition under inert low-pressure conditions using iron (Fe), magnetite (Fe 3 O 4 ), cobalt (Co), and nickel (Ni) targets. Extensive chemical and physical characterization of the added nanoparticles was performed. It was found that for the same synthesis conditions, Fe and Fe 3 O 4 targets resulted in the formation of larger, asymmetrical magnetic Fe nanoparticles with a Fe 3 O 4 shell (Fe@Fe 3 O 4 ) (3.2-8.6 nm) and Fe 3 O 4 (6.0-12.4 nm) nanoparticles, respectively. Smaller, more spherical Co@CoO (2.1-5.0 nm) and Ni@NiO (1.4-3.5 nm) nanoparticles were obtained from the Co and Ni targets, respectively. The highest increase in maximum induced magnetization was observed for multiwalled carbon nanotubes with Fe@Fe 3 O 4 (5.37 ± 0.15 emu/g) or Co@CoO nanoparticles (4.29 ± 0.01) compared to pristine multiwalled carbon nanotubes (2.46 ± 0.08 emu/g) and nanotubes with Fe 3 O 4 (3.79 ± 0.38 emu/g) or Ni@NiO nanoparticles (2.85 ± 0.06 emu/g). Finally, superior adhesion of the Fe@Fe 3 O 4 and Fe 3 O 4 nanoparticles to multiwalled carbon nanotubes compared to the Ni@NiO and Co@CoO nanoparticles was identified., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Intersectoral collaborations are recommended as effective strategies to reduce health inequalities. People most affected by health inequalities, as are people living in poverty, remain generally absent from such intersectoral collaborations. Community-based participatory research (CBPR) projects can be leveraged to better understand how to involve people with lived experience to support both individual and community empowerment. In this paper, we offer a critical reflection on a CBPR project conducted in public housing in Québec, Canada, that aimed to develop intersectoral collaboration between tenants and senior executives from four sectors (housing, health, city and community organizations). This single qualitative case study design consisted of fieldwork documents, observations and semi-structured interviews. Using the Emancipatory Power Framework (EPF) and the Limiting Power Framework (LPF), we describe examples of types of power and resistance shown by the tenants, the intersectoral partners and the research team. The discussion presents lessons learned through the study, including the importance for research teams to reflect on their own power, especially when aiming to reduce health inequalities. The paper concludes by describing the limitations of the analyses conducted through the EPF-LPF frameworks and suggestions to increase the transformative power of future studies., (© The Author(s) 2024. Published by Oxford University Press.)

To explore workers' well-being during COVID-19, researchers have primarily utilized variable-centered approaches (e.g., regression) focusing on describing workers' general level of well-being. Given the diversity of factors that may have impacted workers' well-being during the pandemic, focusing on such well-being trends do not provide sufficient insight into the different lived well-being experiences during the pandemic. Moreover, positive well-being in workers' general lives and work has been understudied in such complex public health crises. To address these issues, we use latent profile analysis, a person-centered analysis, to explore the diverse well-being realities Canadian workers (employed before COVID-19 or working at the time of the survey) experienced at the beginning of COVID-19. Canadian workers ( N  = 510) were surveyed between May 20-27th, 2020, on positive (meaning in life, flourishing, thriving at work) and negative (distress, stress, impaired productivity, troublesome symptoms at work) well-being indicators, as well as on factors that may be associated with experiencing different well-being profiles. Five well-being profiles emerged: moderately prospering, prospering, moderately suffering, suffering, and mixed. Factors at the self- (gender, age, disability status, trait resilience), social- (marital status, family functioning, having children at home), workplace- (some employment statuses and work industries, financial strain, job security), and pandemic-related (perceived vulnerability to COVID-19, social distancing) ecological levels predicted profile membership. Recommendations for employers, policymakers, and mental health organizations are discussed., Competing Interests: Conflict of InterestOn behalf of all authors, the corresponding author states that there is no conflict of interests., (© The Author(s) 2023.)

It is well-known that trans and non-binary individuals experience worse health outcomes due to experiences of violence and discrimination. For this reason, accessible healthcare for trans and non-binary people is crucial. There is a lack of Canadian literature on the experiences of non-binary people within the healthcare system. This study sought to understand barriers to healthcare among non-binary people living in a mid-sized urban/rural region of Canada. Interviews were conducted between November 2019 to March 2020 with 12 non-binary individuals assigned female at birth, living in Waterloo Region, Ontario, Canada, as a part of a larger qualitative study exploring experiences within the community, healthcare and employment. Three broad themes were developed: erasure, barriers to access to healthcare, and assessing whether (or not) to come out. Sub-themes included institutional erasure, informational erasure, general healthcare barriers, medical transition healthcare barriers, anticipated discrimination, and assessing safety. Policy and institutional changes are needed to increase the safety and accessibility of healthcare services to non-binary individuals.

Context In Quebec, adult mental health (AMH) first-line teams are mandated to provide psychosocial services to people living with mental health difficulties, including anxiety and mood disorders. Following the establishment of new clinical guidelines in 2017, the duration of interventions was not to exceed 15 sessions, with some exceptions. Objectives The overall aim of the longitudinal component of the Shared Knowledge study was to evaluate the care experience of individuals with an anxiety or depressive disorder receiving a short-term intervention (<15 sessions) by first-line AMH teams, and the evolution of recovery over time. Specifically, the objectives were to: 1) determine the appreciation of short-term interventions by service users; and 2) assess the evolution over time of the symptomatology, functioning and quality of life and recovery of individuals receiving short-term interventions. Method A mixed method longitudinal design was used. Telephone interviews were conducted with participants, in which the following variables were quantitatively and qualitatively assessed: appreciation of services received, quality of relationship with the provider (INSPIRE), depressive symptoms (PHQ-9), anxiety symptoms (GAD-7), global functioning (WHODAS), quality of life (ReQOL), and personal recovery (ERTAD). Linear mixed model analyses were performed to examine changes over time on quantitative measures. Content analysis was performed on the qualitative data. Results A total of 63 individuals participated in an interview before the start of their intervention and 22 of them participated after the end of this intervention. Statistical analyses showed a significant improvement in anxiety symptoms, quality of life, and personal recovery, but no difference was observed in depressive symptoms and level of functioning. Nearly half (47.4%) of participants reported that the intervention they received had "completely" met the need that had led them to seek help, and 33.3% felt "completely" equipped or empowered in their recovery. The quality of the relationship with the caregiver, the opportunity to take part in decision-making, and the personalization of the intervention according to their needs and preferences were some of the elements that were particularly appreciated. Conclusion Short-term interventions seem to be appreciated and produce positive effects in many people suffering from anxiety or depressive disorders. However, they remain insufficient for a number of them. A personal recovery measure should be used in conjunction with symptomatology and functioning scales to monitor the progress of people using first-line mental health services.

HIV testing and diagnosis are the gateway into treatment and eventual viral suppression. With gay, bisexual, and other men who have sex with men (GBMSM) persistently over-representing new HIV diagnoses in Canada, combined with the evolving nature of community social connection, an exploration of factors associated with recent HIV testing is warranted. As most studies of GBMSM rely on samples obtained from larger metropolitan regions, examining HIV testing from an under-researched region is necessary. With data collected from an online survey of LGBTQ+ persons 16 or older living, working, or residing in the Region of Waterloo, Ontario, Canada, we used multinomial logistic regression to explore socio-demographic, behavioural, and psychosocial factors associated with recent HIV testing for GBMSM. In the final multivariate multinomial logistic regression model: sense of belonging was associated with more recently testing, as was having an increasing proportion of LGBT friends, app use to find sex partners in the past 12 months, access to the local AIDS service organization, and general sense of belonging to local community, among other. This analysis highlights the continued importance of enabling and need factors when accessing testing, and suggests areas for further testing promotion in physical and virtual spaces frequented by GBMSM.

Social media has become increasingly integrated into the lives of students for the past decade; however, the public health restrictions associated with the COVID-19 pandemic have led to a sharp increase in social media use in a short period of time. The purpose of this study was to investigate the effects of social media use on university students during the COVID-19 pandemic. Fifteen students from a mid-sized Canadian city were interviewed to share their experiences with social media during the COVID-19 pandemic. Purposive sampling was conducted to gather a diverse sample of participants, including individuals of various ages, gender and sexual identities, and ethnicities. Thematic analysis on the 15 interviews was completed using NVivo (version 12). Participants experienced both advantages and disadvantages associated with social media use. Ease of communication and stress relief were acknowledged as the strongest benefits. Social comparison, loneliness, development of bad habits, and lack of focus were cited as major disadvantages to social media use during the pandemic. Cost-benefit analysis of social media was common, and participants expressed the importance of using social media with moderation, balance, and awareness. Our study indicates that the focus on health with respect to the pandemic should not be solely based on physical health, rather the potential mental health risks associated with social media use during the pandemic should be recognized and addressed by healthcare providers., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)