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Phytoplankton is exposed to dramatic variations in light quality as it moves up and down the water column or encounters the presence of sediments in the water. We investigated the potential impact onOstreococcus,a key marine photosynthetic picoeukaryote, by analysing changes in its transcriptome, pigment content and photophysiology after acclimation to monochromatic red, green or blue light. The clade B species RCC809, isolated from the deep Atlantic Ocean, responded to blue light by accelerating cell division at the expense of storage reserves, and by increasing the relative level of blue-light absorbing pigments. In contrast, it responded to red and green light by increasing its potential for photoprotection. In contrast, the clade A species OTTH0595, which originates from a shallow water environment, showed no difference in photosynthetic properties and minor differences in carotenoid contents between light qualities. These results demonstrate that light quality can have a major influence on the physiology of eukaryotic phytoplankton, and suggest that different light quality environments can drive selection for diverse patterns of responsiveness and environmental niche partitioning.HighlightWe characterise the effects of light quality on the transcriptome and photophysiology ofOstreococcus, a photosynthetic picoeukaryote, and show that responses are distinct between two ecotypes originating from different environments.

The Canadian population is aging. With aging, biological and social changes occur increasing the risk of developing chronic conditions and functional loss leading to frailty. Older adults living with frailty are more vulnerable to minor stressors, take longer to recover from illness, and have difficulty participating in daily activities. The Canadian Frailty Network’s (CFN) mis-sion is to improve the lives of older adults living with frailty. In September 2019, CFN launched the Activity & Exercise, Vaccination, Optimization of medications, Interaction & Socialization, and Diet & Nutrition (AVOID) Frailty public health campaign to promote assessing and reducing risk fac-tors leading to the development of frailty. As part of the cam-paign, CFN held an Enabling Healthy Aging Symposium with 36 stakeholders from across Canada. Stakeholders identified individual and community-level opportunities and challenges for the enablement of healthy aging and frailty mitigation, as part of a focused consultative process. Stakeholders ranked the three most important challenges and opportunities at the individual and community levels for implementing AVOID Frailty recommendations. Concrete actions, further research areas, policy changes, and existing resources/programs to enhance the AVOID Frailty campaign were identified. The results will help inform future priorities and behaviour change strategies for healthy aging in Canada.

How oligotrophic marine cyanobacteria position themselves in the water column is currently unknown. The current paradigm is that these organisms avoid sinking due to their reduced size and passive drift within currents. Here, we show that one in four picocyanobacteria encode a type IV pilus which allows these organisms to increase drag and remain suspended at optimal positions in the water column, as well as evade predation by grazers. The evolution of this sophisticated floatation mechanism in these purely planktonic streamlined microorganisms has important implications for our current understanding of microbial distribution in the oceans and predator–prey interactions which ultimately will need incorporating into future models of marine carbon flux dynamics., It was thought that marine cyanobacteria drifted randomly in the water column. Here the authors show that one in four picocyanobacteria encode a type IV pilus which allows these organisms to increase drag and retain optimal positions in the water column, as well as evade predation by grazers.

IntroductionWith its legalisation and regulation in Canada in 2018, the proportion of Canadians reporting cannabis use in 2019 increased substantially over the previous year, with half of new users being aged 45+ years. While use in older adults has been low historically, as those born in the 1950s and 1960s continue to age, this demographic will progressively have more liberal attitudes, prior cannabis exposure and higher use rates. However, older adults experience slower metabolism, increased likelihood of polypharmacy, cognitive decline and chronic physical/mental health problems. There is a need to enhance knowledge of the effects of cannabis use in older adults. The following question will be addressed using a scoping review approach: what evidence exists regarding beneficial and harmful effects of medical and non-medical cannabis use in adults >50 years of age? Given that beneficial and harmful effects of cannabis may be mediated by patient-level (eg, age, sex and race) and cannabis-related factors (eg, natural vs synthetic, consumption method), subgroup effects related to these and additional factors will be explored.Methods and analysisMethods for scoping reviews outlined by Arksey & O’Malley and the Joanna Briggs Institute will be used. A librarian designed a systematic search of the literature from database inception to June 2019. Using the OVID platform, Ovid MEDLINE will be searched, including Epub Ahead of Print and In-Process and Other Non-Indexed Citations, Embase Classic+Embase, and PsycINFO for reviews, randomised trials, non-randomised trials and observational studies of cannabis use. The Cochrane Library on Wiley will also be searched. Eligibility criteria will be older adult participants, currently using cannabis (medical or non-medical), with studies required to report a cannabis-related health outcome to be eligible. Two reviewers will screen citations and full texts, with support from artificial intelligence. Two reviewers will chart data. Tables/graphics will be used to map evidence and identify evidence gaps.Ethics and disseminationThis research will enhance awareness of existing evidence addressing the health effects of medical and non-medical cannabis use in older adults. Findings will be disseminated through a peer-reviewed publication, conference presentations and a stakeholder meeting.Trial registration numberDOI 10.17605/OSF.IO/5JTAQ.

The Bridges to Care for Long-Term Care research project aimed to facilitate improvements in outcomes for long-term care residents through the provision of knowledge-to-practice and quality improvement resources by trained facilitators. Point-of-care staff reported improved communication and collaboration, improved use of scope of practice and implementation of best practice knowledge. Overall, participating long-term care homes demonstrated an enhanced capacity for common care issues of the elderly (pneumonia, falls, bacteriuria and behavioural and psychological symptoms of dementia) and the ability to effectively engage in quality improvement processes with efficient and effective use of healthcare resources. Language: en

In recent years, considerable advances have been made in the field of medical isotope metallomics, but numerous fundamental physiological processes remain to be investigated. Past studies report that blood serum Zn concentrations decrease by between about 10 and 25%, depending on the size of meal, approximately three hours postprandially (i.e. after eating), before returning to baseline values if no meals are consumed over the following four to five hours. Nine participants were recruited for this study to investigate whether this postprandial Zn concentration decrease is accompanied by a stable isotope response. A baseline serum sample was collected from participants in the morning after overnight fasting. A 576 kcal meal was then provided and additional serum samples were taken 90 and 180 minutes post-meal to coincide with the postprandial response. Serum Zn concentrations decreased postprandially by an average of 21 ± 9% (1SD), but this was not accompanied by a change in stable Zn isotope composition (mean Δ66Zn180-minute-baseline = 0.01 ± 0.09‰, 2SD). We propose that hemodilution and the rapid, efficient postprandial transfer of albumin-bound Zn from serum to the liver and pancreas is responsible for the lack of postprandial serum Zn isotopic response. These results indicate that studies examining solely the distribution of Zn isotopes in serum may obtain samples without considering timing of the most recent meal. However, future studies seeking to compare serum Zn concentrations with δ66Zn values should draw blood samples in the morning after overnight fasting.

Summary Marine bacterial viruses (bacteriophages) are abundant biological entities that are vital for shaping microbial diversity, impacting marine ecosystem function, and driving host evolution.1, 2, 3 The marine roseobacter clade (MRC) is a ubiquitous group of heterotrophic bacteria4,5 that are important in the elemental cycling of various nitrogen, sulfur, carbon, and phosphorus compounds.6, 7, 8, 9, 10 Bacteriophages infecting MRC (roseophages) have thus attracted much attention and more than 30 roseophages have been isolated,11, 12, 13 the majority of which belong to the N4-like group (Podoviridae family) or the Chi-like group (Siphoviridae family), although ssDNA-containing roseophages are also known.14 In our attempts to isolate lytic roseophages, we obtained two new phages (DSS3_VP1 and DSS3_PM1) infecting the model MRC strain Ruegeria pomeroyi DSS-3. Here, we show that not only do these phages have unusual substitution of deoxythymidine with deoxyuridine (dU) in their DNA, but they are also phylogenetically distinct from any currently known double-stranded DNA bacteriophages, supporting the establishment of a novel family (“Naomiviridae”). These dU-containing phages possess DNA that is resistant to the commonly used library preparation method for metagenome sequencing, which may have caused significant underestimation of their presence in the environment. Nevertheless, our analysis of Tara Ocean metagenome datasets suggests that these unusual bacteriophages are of global importance and more diverse than other well-known bacteriophages, e.g., the Podoviridae in the oceans, pointing to an overlooked role for these novel phages in the environment., Graphical abstract, Highlights • Two new roseophages isolated from the marine environment • They have an unusual deoxythymidine to deoxyuridine substitution in their genomes • These dU genomes are resistant to a common method of metagenome library preparation • These phages represent a new family and are globally distributed in the oceans, Rihtman et al. report the discovery of two novel roseophages containing deoxyuridine (dU) instead of the canonical nucleobase deoxythymidine. Such a substitution results in resistance to a commonly used method for metagenome library preparation, suggesting that the presence of this new family of phages may have been underestimated.

RJP was in receipt of a Natural Environment Research Council (NERC) PhD studentship and a Warwick University IAS Fellowship. This work was also supported in part by NERC grant NE/N003241/1 and Leverhulme Trust grant RPG-2014-354 to A.D.M., D.J.E., and D.J.S. Marine cyanobacteria are responsible for ~25% of the fixed carbon that enters the ocean biosphere. It is thought that abundant co-occurring viruses play an important role in regulating population dynamics of cyanobacteria and thus the cycling of carbon in the oceans. Despite this, little is known about how viral infections ‘play-out’ in the environment, particularly whether infections are resource or energy limited. Photoautotrophic organisms represent an ideal model to test this since available energy is modulated by the incoming light intensity through photophosphorylation. Therefore, we exploited phototrophy of the environmentally relevant marine cyanobacterium Synechococcus and monitored growth of a cyanobacterial virus (cyanophage). We found that light intensity has a marked effect on cyanophage infection dynamics, but that this is not manifest by a change in DNA synthesis. Instead, cyanophage development appears energy limited for the synthesis of proteins required during late infection. We posit that acquisition of auxiliary metabolic genes (AMGs) involved in light-dependent photosynthetic reactions acts to overcome this limitation. We show that cyanophages actively modulate expression of these AMGs in response to light intensity and provide evidence that such regulation may be facilitated by a novel mechanism involving light-dependent splicing of a group I intron in a photosynthetic AMG. Altogether, our data offers a mechanistic link between diurnal changes in irradiance and observed community level responses in metabolism, i.e., through an irradiance-dependent, viral-induced release of dissolved organic matter (DOM). Publisher PDF

R.J.P. was the recipient of a NERC studentship and Warwick University IAS fellowship. This work was supported in part by NERC grant NE/J02273X/1 and Leverhulme Trust grant RPG-2014-354 to A.D.M., D.J.E., and D.J.S. Summary. Marine picocyanobacteria of the genera Prochlorococcus and Synechococcus are the most numerous photosynthetic organisms on our planet [1, 2]. With a global population size of 3.6 × 1027 [3], they are responsible for approximately 10% of global primary production [3, 4]. Viruses that infect Prochlorococcus and Synechococcus (cyanophages) can be readily isolated from ocean waters [5–7] and frequently outnumber their cyanobacterial hosts [8]. Ultimately, cyanophage-induced lysis of infected cells results in the release of fixed carbon into the dissolved organic matter pool [9]. What is less well known is the functioning of photosynthesis during the relatively long latent periods of many cyanophages [10, 11]. Remarkably, the genomes of many cyanophage isolates contain genes involved in photosynthetic electron transport (PET) [12–18] as well as central carbon metabolism [14, 15, 19, 20], suggesting that cyanophages may play an active role in photosynthesis. However, cyanophage-encoded gene products are hypothesized to maintain or even supplement PET for energy generation while sacrificing wasteful CO2 fixation during infection [17, 18, 20]. Yet this paradigm has not been rigorously tested. Here, we measured the ability of viral-infected Synechococcus cells to fix CO2 as well as maintain PET. We compared two cyanophage isolates that share different complements of PET and central carbon metabolism genes. We demonstrate cyanophage-dependent inhibition of CO2 fixation early in the infection cycle. In contrast, PET is maintained throughout infection. Our data suggest a generalized strategy among marine cyanophages to redirect photosynthesis to support phage development, which has important implications for estimates of global primary production. Publisher PDF

Viruses of marine cyanobacteria frequently contain auxiliary metabolic genes (AMGs) that augment host metabolism during infection, but little is known about their adaptive significance. We analyzed the distribution and genomic context of 33 AMGs across 60 cyanomyovirus genomes. Similarity in AMG content among cyanomyoviruses was only weakly correlated with phylogenetic relatedness; however, AMG content was generally conserved within the same operational taxonomic unit (OTU). A virus' AMG repertoire was also correlated with its isolation host and environment (coastal versus open ocean). A new analytical method based on shared co-linear blocks revealed that variation in the genomic location of an AMG was negatively correlated with its frequency across the genomes. We propose that rare AMGs are more frequently gained or lost as a result of fluctuating selection pressures, whereas common AMGs are associated with stable selection pressures. Finally, we describe a unique cyanomyovirus (S-CAM7) that lacks many AMGs including the photosynthesis gene psbA.

Viruses infecting the environmentally important marine cyanobacteria Prochlorococcus and Synechococcus encode ‘auxiliary metabolic genes’ (AMGs) involved in the light and dark reactions of photosynthesis. Here, we discuss progress on the inventory of such AMGs in the ever-increasing number of viral genome sequences as well as in metagenomic datasets. We contextualise these gene acquisitions with reference to a hypothesised fitness gain to the phage. We also report new evidence with regard to the sequence and predicted structural properties of viral petE genes encoding the soluble electron carrier plastocyanin. Viral copies of PetE exhibit extensive modifications to the N-terminal signal peptide and possess several novel residues in a region responsible for interaction with redox partners. We also highlight potential knowledge gaps in this field and discuss future opportunities to discover novel phage–host interactions involved in the photosynthetic process.

As recognition of the need for interdisciplinary geriatric teams grows, new and varied training methods will be necessary to reach health and human service professionals in different contexts and settings. This article reports on the development and evaluation of one such model: an interprofessional educational institute sponsored by the Queen's University Gerontology Project in 1993. Data analyzed include information on participants’ backgrounds and teamwork experience and their assessment of session content and group work processes that made up the knowledge acquisition and skills attainment objectives of the program. Major implications of the institute that became evident include the need to develop a strong institutional foundation, the importance of targeted recruitment, the connection between theory and practice, and the need to present practical techniques, strategies, and modeling opportunities.

Caring for frail seniors requires health professionals with skills and knowledge in 3 core competencies: geriatrics, interprofessional practice, and interorganizational collaboration. Despite a growing population of frail seniors in all developed countries, significant gaps exist in preparation of health professionals in these skills. To help close these gaps, a knowledge-to-practice (KTP) process was undertaken to increase the capacity of newly created family health teams and longer standing Community Health Centers in the Province of Ontario, Canada.Each team identified a staff member to become its facilitator in the 3 core skill sets. Guided by a KTP framework, a set of training modules were created, compiled into a digital toolkit for transfer into practice, translated in a multimethods workshop, and implemented using a variety of strategies to optimize practice change.Staff from 82% of the targeted primary care teams learned to use the toolkit in a train-the-facilitator process that was highly valued, and prompted a range of changes in personal and team practice. A digital toolkit for primary care teams remains an enduring and often used resource.Closing the knowledge gap in the core competencies for frailty focused care is complex. A KTP framework helped guide a staged multimethod process that produced both individual and team practice change and on online toolkit that has a continuing influence.

The optimal development of educational initiatives in the health care of the elderly requires that universities, faculties, and health professionals collaborate on curriculum development. The structure and development of a coalition of five health science centers in Ontario, Canada, are described. The Ontario University Coalition for Education in Health Care of the Elderly seeks to create a collaborative network of educators across the province of Ontario who are committed to the mutual support and encouragement of curriculum developments and dissemination of information and expertise. Some of the strategies that the coalition adopted and the results of its first 5 years of operation are reported.

RÉSUMÉUn recensement auprès de 26 établissements de soins prolongés de la Région d'Ottawa-Carleton, pour un total de 3825 bénéficiaires, a été fait afin d'évaluer la prévalence de démence ou de diminution des capacités cognitives dans la population visée. Les personnes présentant de la démence ou des problèmes de mémoire (selon les critères du DSM III) ont été identifiées par leurs infirmières. Un échantillon «stratifié» et aléatoire a été utilisé pour la validation des données. Les établissements de soins prolongés ont été «stratifies» selon le niveau des soins dispensés et leur grandeur. Onze établissements de chacune des trois strates ont été choisis aléatoirement. Ensuite, un échantillon aléatoire de 10 pour cent avec remplacement (411 bénéficiaires) a été déterminé. L'étude de validation s'est faite par: entrevues avec bénéficiaires utilisant deux instruments de dépistage; entrevues avec infirmières utilisant deux outils de fonctionnement et une révision des dossiers. Le recensement démontre une prévalence de 67 pour cent de problèmes cognitifs pour l'échantillon retenu, comparativement à 52 pour cent dans la population totale des bénéficiaires. La sensibilité du recensement pour la démence est de 95 pour cent et sa spécificité, 83 pour cent. Les résultats indiquent qu'un recensement entrepris par du personnel bien informé et directement impliqué avec les bénéficiaires, selon des definitions standardisées, est une méthode raisonnablement efficace d'estimer la prévalence de démence dans les établissements de soins prolongés.

OBJECTIVES: To determine what treatment decisions physicians will make when faced with an incompetent elderly patient with life-threatening gastrointestinal bleeding and to identify the factors that affect their decisions. DESIGN: Survey. SETTING: Family practice, medical and geriatrics rounds in academic medical centres and community hospitals in seven countries. PARTICIPANTS: Physicians who regularly cared for incompetent elderly patients. OUTCOME MEASURE: A self-administered questionnaire containing three case vignettes. Each provided the same details on an incompetent elderly patient; however, one gave no information about the wishes of the patient and his family (no directive), the second provided a do-not-resuscitate (DNR) request, and the third included a detailed therapeutic and resuscitative effort chart (DTREC) requesting maximum therapeutic care without admission to the intensive care unit (ICU). The four treatment options were supportive care only, limited therapeutic care, maximum therapeutic care without admission to the ICU and maximum care with admission to the ICU. MAIN RESULTS: Treatment decisions varied and were systematically related to age, level of training and country (p less than 0.001). The older physicians and those in family medicine were less likely than the others to choose aggressive treatment options. Brazilian and US physicians were the most aggressive; Australian physicians were the most conservative. The DNR request resulted in a significant decrease in the number of physicians choosing aggressive options (p less than 0.001). The DTREC resulted in a move toward more aggressive treatment, as outlined in the directive (p less than 0.001). Overall, however, about 40% of the physicians chose a level of care different from what had been requested. Furthermore, over 10% would have tried cardiopulmonary resuscitation despite the DNR request. CONCLUSION: Treatment of incompetent elderly patients with life-threatening illness varies widely within and between countries. Uniform standards should be developed on the basis of societal values and be communicated to physicians.