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Background: Manitoba saw the highest number of new HIV diagnoses in the province's history in 2021 and is the only Canadian province not meeting any of the previous UNAIDS 90-90-90 targets. Our goal was to describe sex differences and syndemic conditions within an incident HIV cohort in Manitoba, and the HIV treatment initiation and undetectable viral load outcomes. Methods: This was a retrospective cohort study of all people 18 years and older newly diagnosed with HIV in Manitoba, Canada between January 1st, 2018 and December 31st, 2021. Data was collected as follows: before HIV diagnosis: chlamydia, gonorrhoea, syphilis, and/or hepatitis C antibodies. At the time of HIV diagnosis: age, sex, gender, race/ethnicity, sexual orientation. During follow-up: CD4 counts, viral load, HIV treatment, hospitalizations, and number of visits to HIV care. Main exposures evaluated: methamphetamine use, injection drug use, houselessness, and mental health conditions. Outcomes: started antiretroviral treatment and achieved an undetectable viral load. A descriptive statistical analysis was used. Findings: There were 404 new HIV diagnoses in Manitoba from 2018 to 2021; 44.8% were female, 55.2% male; 76.% self-identified as Indigenous, 13.4% white/European, 4.7% African/black; 86.6% cis-gender; 60.9% heterosexual, 13.4% gay, bisexual and men who have sex with men, and 1.7% lesbian. Injection drug use was reported by 71.8% and 43.5% of females and males respectively. Methamphetamine was the most frequently injected drug (62.4%). Amongst females, 81.8% experienced at least one of the following: houselessness (43.1%), mental health comorbidities (46.4%), and injection drug use (71.8%). Only 64.9% of all individuals had an undetectable viral load (61.1% females and 67.9% males), 56.5% among people experiencing houselessness, 59% among young people (≤29 years), and 60.1% among people who inject drugs. Interpretation: People newly diagnosed with HIV in Manitoba are disproportionately experiencing houselessness, mental illness, and injection drug use (mostly methamphetamine). This pattern is more pronounced for female individuals. These findings highlight the need for syndemic and gender-specific approaches, simultaneously addressing social and health conditions, to treat HIV. Funding: This work was supported by the Canadian Institutes of Health Research, The Manitoba Medical Service Foundation, The James Farley Memorial Fund and the Canada Research Chairs Program.
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The Gigii-Bapiimin study explored the impacts of the COVID-19 pandemic on the health and wellbeing of First Nations, Inuit, and Métis people living with HIV in Manitoba and Saskatchewan, two provinces in Canada with alarmingly high rates of HIV infections. Participants (n = 28 in Manitoba and n = 23 in Saskatchewan) were recruited using various methods, including flyers, community organizations, peers, and social media. The qualitative interviews focused on the pandemic's impact on health, access to services, and ceremonies. The data were analyzed using inductive thematic analysis. The study identified three key themes: (a) resilience and coping; (b) negative impacts on health and substance use; (c) decreased access to health services, HIV care and harm reduction. The participants shared their experiences of social isolation and the loss of community support, which had deleterious effects on their mental health and substance use. The impacts on access to HIV care were exacerbated by poverty, homelessness, and distress over inadvertent disclosure of HIV status. Participants mitigated these impacts by relying on Indigenous knowledges, ceremonies, and resilience within their communities. Service providers must address the impacts of the COVID-19 pandemic on Indigenous people living with HIV and their access to HIV services and ceremonies.
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Adaptación Psicológica , COVID-19 , Infecciones por VIH , Accesibilidad a los Servicios de Salud , Resiliencia Psicológica , SARS-CoV-2 , Humanos , COVID-19/psicología , COVID-19/epidemiología , Saskatchewan/epidemiología , Infecciones por VIH/psicología , Infecciones por VIH/etnología , Masculino , Femenino , Manitoba/epidemiología , Adulto , Persona de Mediana Edad , Investigación Cualitativa , Pueblos Indígenas/psicología , Indígena Canadiense/psicología , Trastornos Relacionados con Sustancias/psicología , Trastornos Relacionados con Sustancias/epidemiología , Pandemias , Salud Mental , Aislamiento Social/psicologíaRESUMEN
BACKGROUND: The stigma associated with human immunodeficiency virus (HIV) is a significant global public health concern. Health care providers and policy makers continue to struggle with understanding and implementing strategies to reduce HIV-related stigma in particular contexts and at the intersections of additional oppressions. Perspectives and direction from people living with HIV are imperative. METHODS: In this project we amplified the voices of people living with HIV about their experiences of HIV-related stigma in Manitoba, Canada. We used an arts-based qualitative case study research design using photovoice and narrative interviews. Adults living with HIV participated by taking pictures that represented their stigma experiences. The photos were a catalyst for conversations about HIV and stigma during follow-up individual narrative interviews. Journaling provided opportunities for participants to reflect on their experiences of, and resistance to, stigma. Interviews were audio recorded and transcribed. Photos, journals, and transcribed interviews were analyzed using inductive qualitative methods RESULTS: Through pictures and dialogue, participants (N = 11; 64% women) expressed the emotional and social impacts of stigmas that were created and supported by oppressive structures and interpersonal attitudes and behaviours. These experiences were compounded by intersecting forms of oppression including racism, sexism, and homophobia. Participants also relayed stories of their personal strategies and transitions toward confronting stigma. Strategies were themed as caring for oneself, caring for children and pets, reconstituting social support networks, and resisting and disrupting stigma. Participants made important recommendations for system and policy change. CONCLUSIONS: These stories of oppression and resistance can inspire action to reduce HIV-related stigma. People living with HIV can consider the strategies to confront stigma that were shared in these stories. Health care providers and policy makers can take concerted actions to support peoples' transitions to resisting stigmas. They can facilitate supportive and anti-oppressive health and social service systems that address medical care as well as basic needs for food, shelter, income, and positive social and community connections.
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Infecciones por VIH , Racismo , Adulto , Niño , Humanos , Femenino , Masculino , VIH , Infecciones por VIH/psicología , Estigma Social , Canadá , Investigación CualitativaRESUMEN
Charge transport properties in single-walled carbon nanotubes (SWCNTs) can be significantly modified through doping, tuning their electrical and thermoelectric properties. In our study, we used more than 40 nitrogen-bearing compounds as dopants and determined their impact on the material's electrical conductivity. The application of nitrogen compounds of diverse structures and electronic configurations enabled us to determine how the dopant nature affects the SWCNTs. The results reveal that the impact of these dopants can often be anticipated by considering their Hammett's constants and pKa values. Furthermore, the empirical observations supported by first-principles calculations indicate that the doping level can be tuned not only by changing the type and the concentration of dopants but also by varying the orientation of nitrogen compounds around SWCNTs.
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Carbon nanotubes (CNTs) are materials with exceptional electrical, thermal, mechanical, and optical properties. Ever since it was demonstrated that they also possess interesting thermoelectric properties, they have been considered a promising solution for thermal energy harvesting. In this study, we present a simple method to enhance their performance. For this purpose, thin films obtained from high-quality single-walled CNTs (SWCNTs) were doped with a spectrum of inorganic and organic halide compounds. We studied how incorporating various halide species affects the electrical conductivity, the Seebeck coefficient, and the Power Factor. Since thermoelectric devices operate under non-ambient conditions, we also evaluated these materials' performance at elevated temperatures. Our research shows that appropriate dopant selection can result in almost fivefold improvement to the Power Factor compared to the pristine material. We also demonstrate that the chemical potential of the starting CNT network determines its properties, which is important for deciphering the true impact of chemical and physical functionalization of such ensembles.
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This paper investigates coupling between electromagnetic surface waves on parallel wires. Finite-element method (FEM)-based and analytic models are developed for single- and double-wire Sommerfeld and Goubau lines. Models are validated via measurements for Goubau lines and a comparison between the analytic and the FEM-based computations for coupled Sommerfeld- and Goubau-type lines is carried out. The measurements and calculations show remarkable agreement. The FEM-based and analytic models match remarkably well too. The results exhibit new favourable effects for surface waves propagation over multiple conductors. The short-range behaviour of the coupled wires and, consequently, the existence of an optimum separation of coupled wires is one of the most significant findings of this paper. We comment on the relevance of our results, particularly in relation to applications of high bandwidth demands and cross-coupling effects.
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Planar Goubau lines show promise as high frequency, low-loss waveguides on a substrate. However, to date only numerical simulations and experimental measurements have been performed. This paper analytically investigates the surface wave mode propagating along a planar Goubau line consisting of a perfectly conducting circular wire on top of a dielectric substrate of finite thickness but infinite width. An approximate equation for the propagation constant is derived and solved through numerical integration. The dependence of the propagation constant on various system parameters is calculated and the results agree well with full numerical simulations. In addition, the spatial distribution of the longitudinal electric field is reported and excellent agreement with a numerical simulation and previous studies is found. Moreover, validation against experimental phase velocity measurements is also reported. Finally, insights gained from the model are considered for a Goubau line with a rectangular conductor. The analytic model reveals that the propagating mode of a planar Goubau line is hybrid in contrast to the transverse magnetic mode of a classic Goubau line.
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The fundamental colloidal properties of pristine graphene flakes remain incompletely understood, with conflicting reports about their chemical character, hindering potential applications that could exploit the extraordinary electronic, thermal, and mechanical properties of graphene. Here, the true amphipathic nature of pristine graphene flakes is demonstrated through wet-chemistry testing, optical microscopy, electron microscopy, and density functional theory, molecular dynamics, and Monte Carlo calculations, and it is shown how this fact paves the way for the formation of ultrastable water/oil emulsions. In contrast to commonly used graphene oxide flakes, pristine graphene flakes possess well-defined hydrophobic and hydrophilic regions: the basal plane and edges, respectively, the interplay of which allows small flakes to be utilized as stabilizers with an amphipathic strength that depends on the edge-to-surface ratio. The interactions between flakes can be also controlled by varying the oil-to-water ratio. In addition, it is predicted that graphene flakes can be efficiently used as a new-generation stabilizer that is active under high pressure, high temperature, and in saline solutions, greatly enhancing the efficiency and functionality of applications based on this material.
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First-principles electronic structure calculations are now accessible to a very large community of users across many disciplines, thanks to many successful software packages, some of which are described in this special issue. The traditional coding paradigm for such packages is monolithic, i.e., regardless of how modular its internal structure may be, the code is built independently from others, essentially from the compiler up, possibly with the exception of linear-algebra and message-passing libraries. This model has endured and been quite successful for decades. The successful evolution of the electronic structure methodology itself, however, has resulted in an increasing complexity and an ever longer list of features expected within all software packages, which implies a growing amount of replication between different packages, not only in the initial coding but, more importantly, every time a code needs to be re-engineered to adapt to the evolution of computer hardware architecture. The Electronic Structure Library (ESL) was initiated by CECAM (the European Centre for Atomic and Molecular Calculations) to catalyze a paradigm shift away from the monolithic model and promote modularization, with the ambition to extract common tasks from electronic structure codes and redesign them as open-source libraries available to everybody. Such libraries include "heavy-duty" ones that have the potential for a high degree of parallelization and adaptation to novel hardware within them, thereby separating the sophisticated computer science aspects of performance optimization and re-engineering from the computational science done by, e.g., physicists and chemists when implementing new ideas. We envisage that this modular paradigm will improve overall coding efficiency and enable specialists (whether they be computer scientists or computational scientists) to use their skills more effectively and will lead to a more dynamic evolution of software in the community as well as lower barriers to entry for new developers. The model comes with new challenges, though. The building and compilation of a code based on many interdependent libraries (and their versions) is a much more complex task than that of a code delivered in a single self-contained package. Here, we describe the state of the ESL, the different libraries it now contains, the short- and mid-term plans for further libraries, and the way the new challenges are faced. The ESL is a community initiative into which several pre-existing codes and their developers have contributed with their software and efforts, from which several codes are already benefiting, and which remains open to the community.
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We investigate a model which shows how the introduction of a perturbing dielectric close to an electromagnetic surface wave leads to radiation away from the surface through the dielectric. This resembles a surface waveguide passing through a wall or being deployed underground. Our theory, which is based on the mode-matching technique, allows quantitative determination of losses from a bound surface wave mode up to the point of its complete extinction. For a surface wave supported by a coated, conducting sheet the attenuation due to the perturbing dielectric is calculated for a number of frequencies, permittivities of the perturbation and separations between the sheet and the perturbing dielectric. The accuracy of our results is verified by simulation of the system with a full-wave numerical solution. Finally, we report experimental data of perturbed surface waves on a cable, which are in qualitative agreement with our model.
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We present an overview of the onetep program for linear-scaling density functional theory (DFT) calculations with large basis set (plane-wave) accuracy on parallel computers. The DFT energy is computed from the density matrix, which is constructed from spatially localized orbitals we call Non-orthogonal Generalized Wannier Functions (NGWFs), expressed in terms of periodic sinc (psinc) functions. During the calculation, both the density matrix and the NGWFs are optimized with localization constraints. By taking advantage of localization, onetep is able to perform calculations including thousands of atoms with computational effort, which scales linearly with the number or atoms. The code has a large and diverse range of capabilities, explored in this paper, including different boundary conditions, various exchange-correlation functionals (with and without exact exchange), finite electronic temperature methods for metallic systems, methods for strongly correlated systems, molecular dynamics, vibrational calculations, time-dependent DFT, electronic transport, core loss spectroscopy, implicit solvation, quantum mechanical (QM)/molecular mechanical and QM-in-QM embedding, density of states calculations, distributed multipole analysis, and methods for partitioning charges and interactions between fragments. Calculations with onetep provide unique insights into large and complex systems that require an accurate atomic-level description, ranging from biomolecular to chemical, to materials, and to physical problems, as we show with a small selection of illustrative examples. onetep has always aimed to be at the cutting edge of method and software developments, and it serves as a platform for developing new methods of electronic structure simulation. We therefore conclude by describing some of the challenges and directions for its future developments and applications.
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OBJECTIVE: To examine the outcomes of a Medicare population who participated in a program combining digital health with human coaching for diabetes risk reduction. METHOD: People at risk for diabetes enrolled in a program combining digital health with human coaching. Participation and health outcomes were examined at 16 weeks and 6 and 12 months. RESULTS: A total of 501 participants enrolled; 92% completed at least nine of 16 core lessons. Participants averaged 19 of 31 possible opportunities for weekly program engagement. At 12 months, participants lost 7.5% ( SD = 7.8%) of initial body weight; among participants with clinical data, glucose control improved (glycosylated hemoglobin [HbA1c] change = -0.14%, p = .001) and total cholesterol decreased (-7.08 mg/dL, p = .008). Self-reported well-being, depression, and self-care improved ( p < .0001). DISCUSSION: This Medicare population demonstrated sustained program engagement and improved weight, health, and well-being. The findings support digital programs with human coaching for reducing chronic disease risk among older adults.
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Diabetes Mellitus Tipo 2 , Servicios Preventivos de Salud , Conducta de Reducción del Riesgo , Autocuidado , Anciano , Diabetes Mellitus Tipo 2/prevención & control , Diabetes Mellitus Tipo 2/psicología , Femenino , Hemoglobina Glucada/análisis , Promoción de la Salud/métodos , Humanos , Masculino , Medicare/estadística & datos numéricos , Persona de Mediana Edad , Servicios Preventivos de Salud/métodos , Servicios Preventivos de Salud/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud , Autocuidado/métodos , Autocuidado/psicología , Telemedicina/métodos , Estados Unidos/epidemiologíaRESUMEN
Indigenous peoples (First Nations, Inuit, and Métis) are currently overrepresented in the HIV epidemic in Canada and are infected at a younger age than those who are not Indigenous. This article presents our findings on the stigma and discrimination (as well as related themes such as disclosure) experienced by Indigenous people who contracted HIV in their youth and live in urban and non-urban settings in Manitoba, Canada. The findings were derived from a qualitative study that sought to understand the experiences and needs of Indigenous people living with HIV (including AIDS). We situate such experiences within a social ecological framework towards developing a better structural understanding of the impacts of stigma and discrimination on the lives of Indigenous people who are HIV positive. Stigma and discrimination caused barriers for Indigenous people living with HIV through inhibiting their ease of access to supports including family, peers, community, and long- and short-term health services. Creative forms of outreach and education that are culturally appropriate and/or rooted in culture were considered to be possibly impactful ways of reducing stigma and discrimination at the community level. Learning from communities who are successfully managing stigma also showed promise for developing new programming.
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Grupos de Población/psicología , Medio Social , Adolescente , Adulto , Femenino , Infecciones por VIH/epidemiología , Humanos , Masculino , Manitoba/epidemiología , Manitoba/etnología , Grupos de Población/etnología , Investigación Cualitativa , Racismo/etnología , Estigma SocialRESUMEN
BACKGROUND: Indigenous young people are currently highly overrepresented in the HIV epidemic in Canada, especially in the Prairie Provinces, such as Manitoba. Understanding HIV-vulnerability in Indigenous peoples must begin with understanding that social determinants are intersectional and linked to the historical legacy of European colonization. In this paper findings that detail the influence of the intersectional social determinants on Indigenous people who become infected with HIV in their youth are presented. METHODS: The qualitative research design of phenomenology was used as it afforded the opportunity to understand Indigenous young people from their frames of reference and experiences of reality, resulting in a phenomenological understanding of their perspectives and experiences of the early years of living with HIV. A total of 21 Indigenous young people took part open-ended interviews. RESULTS: The stories that the Indigenous young people shared revealed their deeply interconnected social worlds, and how social determinants including abuse, trauma, being part of the child welfare system, and housing and food security were connected throughout various stages of their lives. Such stages included childhood, adolescence and young adulthood (the time of HIV infection), and later adulthood for older participants with the social determinants having multiple influences on their health trajectories. CONCLUSIONS: The findings highlight the need for policies and programs that are broadly focused, addressing multiple social determinants together. Overall, there needs to be more emphasis on the multiple social determinants in the life situations of all Indigenous youth. Reducing the health and social disparities in Indigenous youth is key to reducing the number of young Indigenous people diagnosed with HIV. The findings also shed light on the importance of listening to young Indigenous people who have experienced HIV diagnosis and life following diagnosis.
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Epidemias , Infecciones por VIH/epidemiología , Disparidades en el Estado de Salud , Grupos de Población/estadística & datos numéricos , Determinantes Sociales de la Salud , Adolescente , Adulto , Canadá/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Adulto JovenRESUMEN
Background. The feasibility of digital health programs to prevent and manage diabetes in low-income patients has not been adequately explored. Methods. Researchers collaborated with a digital health company to adapt a diabetes prevention program for low-income prediabetes patients at a large safety net clinic. We conducted focus groups to assess patient perspectives, revised lessons for improved readability and cultural relevance to low-income and Hispanic patients, conducted a feasibility study of the adapted program in English and Spanish speaking cohorts, and implemented real-time adaptations to the program for commercial use and for a larger trial of in multiple safety net clinics. Results. The majority of focus group participants were receptive to the program. We modified the curriculum to a 5th-grade reading level and adapted content based on patient feedback. In the feasibility study, 54% of eligible contacted patients expressed interest in enrolling (n = 23). Although some participants' computer access and literacy made registration challenging, they were highly satisfied and engaged (80% logged in at least once/week). Conclusions. Underserved prediabetic patients displayed high engagement and satisfaction with a digital diabetes prevention program despite lower digital literacy skills. The collaboration between researchers and a digital health company enabled iterative improvements in technology implementation to address challenges in low-income populations.
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Diabetes Mellitus Tipo 2/prevención & control , Promoción de la Salud , Adolescente , Adulto , Anciano , Estudios de Factibilidad , Femenino , Grupos Focales , Hispánicos o Latinos , Humanos , Masculino , Persona de Mediana Edad , Satisfacción Personal , Pobreza , Evaluación de Programas y Proyectos de Salud , Adulto JovenRESUMEN
BACKGROUND: Type 2 diabetes and cardiovascular disease impose substantial clinical and economic burdens for seniors (age 65 and above) and the Medicare program. Intensive Behavioral Counseling (IBC) interventions like the National Diabetes Prevention Program (NDPP), have demonstrated effectiveness in reducing excess body weight and lowering or delaying morbidity onset. This paper estimated the potential health implications and medical savings of a digital version of IBC modeled after the NDPP. METHODS AND FINDINGS: Participants in this digital IBC intervention, the Omada program, include 1,121 overweight or obese seniors with additional risk factors for diabetes or heart disease. Weight changes were objectively measured via participant use of a networked weight scale. Participants averaged 6.8% reduction in body weight within 26 weeks, and 89% of participants completed 9 or more of the 16 core phase lessons. We used a Markov-based microsimulation model to simulate the impact of weight loss on future health states and medical expenditures over 10 years. Cumulative per capita medical expenditure savings over 3, 5 and 10 years ranged from $1,720 to 1,770 (3 years), $3,840 to $4,240 (5 years) and $11,550 to $14,200 (10 years). The range reflects assumptions of weight re-gain similar to that seen in the DPP clinical trial (lower bound) or minimal weight re-gain aligned with age-adjusted national averages (upper bound). The estimated net economic benefit after IBC costs is $10,250 to $12,840 cumulative over 10 years. Simulation outcomes suggest reduced incidence of diabetes by 27-41% for participants with prediabetes, and stroke by approximately 15% over 5 years. CONCLUSIONS: A digital, remotely-delivered IBC program can help seniors at risk for diabetes and cardiovascular disease achieve significant weight loss, reduces risk for diabetes and cardiovascular disease, and achieve meaningful medical cost savings. These findings affirm recommendations for IBC coverage by the U.S. Preventive Services Task Force.
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Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/prevención & control , Consulta Remota/métodos , Programas de Reducción de Peso/métodos , Anciano , Anciano de 80 o más Años , Enfermedades Cardiovasculares/economía , Análisis Costo-Beneficio , Consejo , Diabetes Mellitus Tipo 2/economía , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Masculino , Cadenas de Markov , Medicare , Modelos Teóricos , Factores de Riesgo , Estados UnidosRESUMEN
Molecular mechanics force fields, which are commonly used in biomolecular modeling and computer-aided drug design, typically treat nonbonded interactions using a limited library of empirical parameters that are developed for small molecules. This approach does not account for polarization in larger molecules or proteins, and the parametrization process is labor-intensive. Using linear-scaling density functional theory and atoms-in-molecule electron density partitioning, environment-specific charges and Lennard-Jones parameters are derived directly from quantum mechanical calculations for use in biomolecular modeling of organic and biomolecular systems. The proposed methods significantly reduce the number of empirical parameters needed to construct molecular mechanics force fields, naturally include polarization effects in charge and Lennard-Jones parameters, and scale well to systems comprised of thousands of atoms, including proteins. The feasibility and benefits of this approach are demonstrated by computing free energies of hydration, properties of pure liquids, and the relative binding free energies of indole and benzofuran to the L99A mutant of T4 lysozyme.