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To provide high-energy, high-power beams at short wavelengths for inertial-confinement fusion experiments, we routinely convert the 1.05-micrometer output of the Nova, Nd:phosphate-glass, laser system to its second- or third-harmonic wavelength. We describe the design and performance of the 3 x 3 arrays of potassium dihydrogen phosphate crystal plates used for type-II-type-II phase-matched harmonic conversion of the Nova 0.74-m diameter beams. We also describe an alternate type-I-type-II phase-matching configuration that improves third-harmonic conversion efficiency. These arrays provide conversion of a Nova beam of up to 75% to the second harmonic and of up to 70% to the third harmonic.

High-powered glass-laser systems with multiple beams, frequency-conversion capabilities, and pulse-shaping flexibility have made numerous contributions to the understanding of inertial confinement fusion and related laser-plasma interactions. The Nova laser at Lawrence Livermore National Laboratory is the largest such laser facility. We have made improvements to the Nova amplifier system that permit increased power and energy output. We summarize the nonlinear effects that now limit Nova's performance and discuss power and energy produced at 1.05-, 0.53-, and 0.35 micrometer wavelengths, including the results with pulses temporally shaped to improve inertial confinement fusion target performance.

We demonstrate temporal shaping of 0.35-[mu]m-wavelength pulses produced by a third-harmonic conversion of the output from the Nova Nd:phosphate glass-laser amplifier system for use in inertial confinement fusion experiments. We describe the computer models used to calculate the pulse shape that is required as the input to the amplifier system, the experimental apparatus used to produce these pulses, and the high-power 0.35-[mu]m shaped pulses produced in recent experiments.

Background: People living with human immunodeficiency virus (HIV) are living longer with health-related disability associated with ageing, including complex conditions. However, health systems in Canada have not adapted to meet these comprehensive care needs., Methods: We convened three citizen panels and a national stakeholder dialogue. The panels were informed by a plain-language citizen brief that outlined data and evidence about the challenge/problem, elements of an approach for addressing it and implementation considerations. The national dialogue was informed by a more detailed version of the same brief that included a thematic analysis of the findings from the panels., Results: The 31 citizen panel participants emphasized the need for more prevention, testing and social supports, increased public education to address stigma and access to more timely data to inform system changes. The 21 system leaders emphasized the need to enhance person-centred care and for implementing learning and improvement across provinces, territories and Indigenous communities. Citizens and system leaders highlighted that policy actions need to acknowledge that HIV remains unique among conditions faced by Canadians., Conclusions: Action will require a national learning collaborative to support spread and scale of successful prevention, care and support initiatives. Such a collaborative should be grounded in a rapid-learning and improvement approach that is anchored on the needs, perspectives and aspirations of people living with HIV; driven by timely data and evidence; supported by appropriate decision supports and aligned governance, financial and delivery arrangements; and enabled with a culture of and competencies for rapid learning and improvement., (© 2024. The Author(s).)

Purpose: The LHIV-Manitoba cohort was developed as a way to provide a comprehensive source of HIV-related health information in the central Canadian Prairie province of Manitoba. The cohort will provide important information as we aim to better understand local HIV epidemiology and address key knowledge and practice gaps in HIV prevention, treatment and care programming in the province., Participants: In total, 890 individuals, aged 18 or older and living or receiving HIV care in Manitoba are enrolled in the cohort. A complete clinical dataset exists for 725 participants, which includes variables on sociodemographic characteristics, comorbidities and co-infections, self-reported HIV exposure categories and HIV clinical indicators. A limited clinical dataset exists for an additional 165 individuals who were enrolled posthumously. 97.5% of cohort participants' clinical records are linked to provincial administrative health datasets., Findings to Date: The average age of cohort participants is 49.7 years. Approximately three-quarters of participants are male, 42% self-identified as white and 42% as Indigenous. The majority of participants (64%) reported condomless vaginal sex as a risk exposure for HIV. Nearly one-fifth (18%) of participants have an active hepatitis C virus infection and the cohort's median CD4 count increased from 316 cells/mm 3 to 518 cells/mm 3 between time of entry into care and end of the first quarter in 2019., Future Plans: The LHIV-Manitoba cohort is an open cohort, and as such, participant enrolment, data collection and analyses will be continually ongoing. Future analyses will focus on the impact of provincial drug plans on clinical outcomes, determinants of mortality among cohort participants and deriving estimates for a local HIV care cascade., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background. Electronic consultation (eConsultation) is a potential strategy to improve access to specialist expertise and facilitate collaborative care models. The Champlain BASE eConsult service allows for asynchronous communication between primary care providers (PCP) and specialists on a secure, web-based system. HIV experts accessible include HIV physician specialists, HIV pharmacists, and social workers with expertise in HIV. Objective. This study aims to describe the use, value, and utility of this eConsultation service in the care of people living with HIV and to characterize the common question types and clinical topics asked by PCPs. Methods. We analyzed the data from eConsults sent to the HIV specialty group in Ontario's Champlain Local Health Integration Network between February 2015 and December 2017. Usage data and close-out survey responses were analyzed using descriptive statistics, eConsults were classified using a predefined list of validated taxonomy, and a thematic analysis was performed on the consultation logs to identify common clinical themes. Results. Among the 46 eConsults, the most common question type related to drug treatment (58.7%, n = 27) and management (19.6%, n = 9). The main clinical themes involved the care of significant complexities in people living with HIV, such as comorbidities and drug interactions, and suggestions of coordinated patient care. As well, eConsult was used for advice regarding pre-exposure prophylaxis for HIV-negative patients at risk of HIV infection. PCPs highly valued the eConsult service (average rating 4.8/5). Conclusion. Overall, this study demonstrates that eConsult provides an efficient and valuable service to PCPs caring for patients living with or at risk for HIV by improving access to HIV specialists and facilitating the delivery of team-based comprehensive care., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

In 2013, the Living with HIV (LHIV) Innovation team established clinical cohorts of people living with HIV in Manitoba and Newfoundland and Labrador, and they linked the data to provincial health administrative databases. Access to these data enabled researchers to conduct studies across provincial borders; contribute to a national dialogue on HIV health system performance; and give recommendations for evidence-based healthcare, health policy and public health. However, research funding is episodic; maintaining cohorts requires stable funding. We support the establishment of a cross-jurisdictional approach to facilitate streamlined data collection and linkage without interruption and to allow for meaningful analysis in order to inform national policies., (Copyright © 2019 Longwoods Publishing.)

With the advent of continuous antiretroviral therapy, HIV has become a complex chronic, rather than acute, condition. The Chronic Care Model (CCM) provides an integrated approach to the delivery of care for people with chronic conditions that could therefore be applied to the delivery of care for people living with HIV. Our objective was to assess the alignment of HIV care settings with the CCM. We conducted a mixed methods study to explore structures, organization and care processes of Canadian HIV care settings. The quantitative results of phase one are published elsewhere. For phase two, we conducted semi-structured interviews with key informants from 12 HIV care settings across Canada. Irrespective of composition of the care setting or its location, HIV care in Canada is well aligned with several components of the CCM, most prominently in the areas of linkage to community resources and delivery system design with inter-professional team-based care. We propose the need for improvements in the availability of electronic clinical information systems and self-management support services to support better care delivery and health outcomes among people living with HIV in Canada., Competing Interests: The authors have declared that no competing interests exist.

Purpose: For people living with HIV (PLWH) using continuous antiretroviral therapy, HIV is now a complex chronic condition often managed in primary care settings. The patient-centered medical home (PCMH) is a model to deliver comprehensive, coordinated, and integrated primary care that promotes collaboration between primary and specialist care and allied services. The study assessed how both Canadian primary and specialist HIV care settings align with the PCMH., Methods: Mixed-methods surveys and interviews with providers in Canadian HIV care settings., Results: Twenty-two settings completed the survey, 12 of which participated in follow-up interviews. Settings had a mean PCMH score of 8.06/12 (SD = 1.53), indicating the basic elements of each PCMH domain have been implemented. We found no significant differences between HIV primary care and specialist care settings. Continuous team-based healing relationships had the highest score (mean = 9.2; SD = 2.15), and quality improvement strategy had the lowest score (mean = 7.19; SD = 2.26). The themes that arose from the interviews were 1) endorsement of the domains of the PCMH by all settings, 2) organizational structures of settings located in hospitals facilitating the implementation of the PCMH through existing technology, patient advisory boards, and accessible services, and 3) dissonance between complex care needs and existing organizational structures in some settings, including limited clinic hours, lack of electronic medical records, and limited mental health services., Conclusions: HIV care in Canada is reasonably well aligned with the PCMH, irrespective of structure of settings. We propose the need for improvements in the use of electronic medical records, quality improvement strategies, and integration of mental health services to achieve better care delivery and health outcomes among PLWH in Canada., Competing Interests: Conflict of interest: none declared., (© Copyright 2019 by the American Board of Family Medicine.)

HIV treatment in Canada has rapidly progressed with the advent of new drug therapies and approaches to care. With this evolution, there is increasing interest in Canada in understanding the current delivery of HIV care, specifically where care is delivered, how, and by whom, to inform the design of care models required to meet the evolving needs of the population. We conducted a cross-sectional survey of Canadian care settings identified as delivering HIV care between June 2015 and January 2016. Given known potential differences in delivery approaches, we stratified settings as primary care or specialist settings, and described their structure, geographic location, populations served, health human resources, technological resources, and available clinical services. We received responses from 22 of 43 contacted care settings located in seven Canadian provinces (51.2% response rate). The total number of patients and HIV patients served by the participating settings was 38,060 and 17,678, respectively (mean number of HIV patients in primary care settings = 1,005, mean number of HIV patients in specialist care settings = 562). Settings were urban for 20 of the 22 (90.9%) clinics and 14 (63.6%) were entirely HIV focused. Primary care settings were more likely to offer preventative services (e.g., cervical smear, needle exchange, IUD insertion, chronic disease self-management program) than specialist settings. The study illustrates diversity in Canadian HIV care settings. All settings were team based, but primary care settings offered a broader range of preventative services and comprehensive access to mental health services, including addictions and peer support., Competing Interests: The authors have declared that no competing interests exist.

Purpose: To evaluate the safety, tolerability, and efficacy of supported standing in a small sample of boys with Duchenne muscular dystrophy (DMD)., Methods: Four 12- to 15-year-old boys with DMD engaged in a home-based supported standing program for 6 to 12 months. A single-subject design was employed to examine muscle length. Bone mineral density was assessed at 4-month intervals using dual-energy x-ray absorptiometry., Results: Upright, sustained supported standing was tolerated in 3 of the 4 boys. Mean weekly stand times ranged from 1.3 to 3.3 hours. Improved hip or knee flexor muscle length was seen in 3 of the 4 boys. No boys showed improved plantar flexor muscle length or increased lumbar bone mineral density., Conclusions: Findings offer preliminary empirical evidence addressing the safety, tolerability, and efficacy of standing in boys with DMD. Additional research with an emphasis on better program adherence is indicated.

The stimulated Raman-scattering (SRS) gain coefficient has been measured quantitatively for the first time to our knowledge in Yb:Sr(5)(PO(4))(3)F to be 1.23 ? 0.12 cm/GW at 1053 nm. These data, along with surface and bulk losses, feedback that is due to surface reflections, gain saturation, and bandwidth, have been applied to a quantitative model that predicts the effects of SRS within a laser amplifier system where the laser gain media show SRS gain. Limitations and impact to the laser amplifier performance are discussed, along with possible techniques to reduce SRS loss.

We report on the experimental measurement of the saturated gain of Yb(3+):Sr(5)(PO(4))(3)F at the 1047-nm laser line as a function of pump fluence and probe energy. The emission line was accurately modeled as a single homogeneous extraction, yielding values of 6.2 x 10(-20) cm(2) for the emission cross section and 3.3 J/cm(2) for the saturation fluence.

Sequence comparisons of small subunit ribosomal RNA coding regions from 12 chlorophylls a + c-containing algae were used to infer phylogenetic relationships within the Chromophyta. Three chromophyte lines of descent, delineated by the Bacillariophyceae, the Phaeophyceae/Xanthophyceae, and the Chrysophyceae/Eustigmatophyceae/Synurophyceae are members of a complex evolutionary assemblage, which also includes representatives of the Oomycota ("lower" fungi). Maximum parsimony and distance matrix methods demonstrate a common evolutionary history for these lineages but their relative branching order could not be determined. Other algal species with chlorophylls a + c, including dinoflagellates and prymnesiophytes, are not members of this complex assemblage. Dinoflagellates are specifically related to apicomplexans and ciliates, and the prymnesiophyte, Emiliania huxleyi, represents an independent photosynthetic lineage that separated from other eukaryotes during the nearly simultaneous divergence of plants, animals, fungi, and a number of other protist lineages. The small subunit rRNA phylogenies of chromophytes/oomycetes were compared to those derived from comparisons of ultrastructural characters. Only tubular, tripartite mastigonemes (flagellar hairs) characterized all studied taxa of chromophytes/oomycetes as a monophyletic assemblage., (© 1992 The Society for the Study of Evolution.)