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1.
Am J Primatol ; : e23615, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467477

RESUMO

Forest loss and degradation due to land cover changes imperil biodiversity worldwide. Subtropical and tropical ecosystems experience high deforestation rates, negatively affecting species like primates. Madagascar's endemic lemurs face exceptionally high risks of population declines and extirpation. We examined how short-term land cover changes within a fragmented landscape in southeastern Madagascar impacted the density of lemur species. Using line transects, we assessed density changes in nine lemur species across five forest fragments. Diurnal surveys were conducted monthly from 2015 to 2019 on 35 transects (total effort = 1268 km). Additionally, 21 transects were surveyed nocturnally in 2015 and 2016 (total effort = 107.5 km). To quantify forest cover changes, we generated land use/land cover (LULC) maps from Sentinel-2 imagery using supervised classification for each year. For the LULC maps, we overlayed species-specific buffers around all transects and calculated the proportion of land cover classes within them. We observed declines in the annual densities of four diurnal and cathemeral lemur species between 2015 and 2019, with species-specific declines of up to 80% (Varecia variegata). While the density of two nocturnal species decreased, one increased fivefold (Cheirogaleus major) between 2015 and 2016. By 2019, Grassland was the dominant land type (50%), while Paddy Fields had the smallest coverage (1.03%). Mature Agricultural Land increased the most (63.37%), while New Agricultural Land decreased the most (-66.36%). Unexpectedly, we did not find evidence that higher forest cover supported a higher lemur population density within sampled areas, but we found support for the negative impact of degraded land cover types on three lemur species. Our study underscores the urgent need to address land-use changes and their repercussions for primate populations in tropical ecosystems. The diverse responses of lemur species to modified habitats highlight the complexity of these impacts and emphasize the importance of targeted conservation efforts.

2.
Oecologia ; 201(4): 1123-1136, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37017733

RESUMO

Climate change represents a growing ecological challenge. The (sub) arctic and boreal regions of the world experience the most rapid warming, presenting an excellent model system for studying how climate change affects mammals. Moose (Alces alces) are a particularly relevant model species with their circumpolar range. Population declines across the southern edge of this range are linked to rising temperatures. Using a long-term dataset (1988-1997, 2017-2019), we examine the relative strength of direct (thermoregulatory costs) and indirect (food quality) pathways linking temperature, precipitation, and the quality of two important food items (birch and fireweed) to variation in moose calf mass in northern Sweden. The direct effects of temperature consistently showed stronger relationships to moose calf mass than did the indirect effects. The proportion of growing season days where the temperature exceeded a 20 °C threshold showed stronger direct negative relationships to moose calf mass than did mean temperature values. Finally, while annual forb (fireweed) quality was more strongly influenced by temperature and precipitation than were perennial (birch) leaves, this did not translate into a stronger relationship to moose calf weight. The only indirect path with supporting evidence suggested that mean growing season temperatures were positively associated with neutral detergent fiber, which was, in turn, negatively associated with calf mass. While indirect impacts of climate change deserve further investigation, it is important to recognize the large direct impacts of temperature on cold-adapted species.


Assuntos
Cervos , Animais , Estações do Ano , Temperatura , Mudança Climática , Regiões Árticas
3.
Can J Cardiol ; 39(6): 741-753, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37030518

RESUMO

Approximately 15% of adult Canadians with SARS-CoV-2 infection develop lingering symptoms beyond 12 weeks after acute infection, known as post-COVID condition or long COVID. Some of the commonly reported long COVID cardiovascular symptoms include fatigue, shortness of breath, chest pain, and palpitations. Suspected long-term cardiovascular complications of SARS-CoV-2 infection might present as a constellation of symptoms that can be challenging for clinicians to diagnose and treat. When assessing patients with these symptoms, clinicians need to keep in mind myalgic encephalomyelitis/chronic fatigue syndrome, postexertional malaise and postexertional symptom exacerbation, dysautonomia with cardiac manifestations such as inappropriate sinus tachycardia, and postural orthostatic tachycardia syndrome, and occasionally mast cell activation syndrome. In this review we summarize the globally evolving evidence around management of cardiac sequelae of long COVID. In addition, we include a Canadian perspective, consisting of a panel of expert opinions from people with lived experience and experienced clinicians across Canada who have been involved in management of long COVID. The objective of this review is to offer some practical guidance to cardiologists and generalist clinicians regarding diagnostic and treatment approaches for adult patients with suspected long COVID who continue to experience unexplained cardiac symptoms.


Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , Adulto , Humanos , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/terapia , Canadá/epidemiologia , SARS-CoV-2 , Coração
4.
Proc Natl Acad Sci U S A ; 119(42): e2121105119, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36215474

RESUMO

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use.


Assuntos
Evolução Biológica , Primatas , América , Animais , Cercopithecidae , Haplorrinos , Humanos , Madagáscar , Mamíferos , Árvores
5.
Can J Diabetes ; 46(8): 835-842.e1, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36088215

RESUMO

OBJECTIVES: One-third of adults in Canada are overweight and 26.8% experience obesity. Bariatric surgery confers effective weight loss and reduces obesity-related complications, including type 2 diabetes, but remains an underutilized treatment. Our objective in this study was to determine whether a gap exists in bariatric program referrals for patients with type 2 diabetes seen in endocrinology clinics at an ambulatory tertiary care hospital in Toronto, Canada. METHODS: A retrospective chart review was conducted of 843 consecutive patients with type 2 diabetes in endocrinology clinics between January 1, 2015 and December 31, 2020. Inclusion criteria were age ≥18 years, type 2 diabetes and body mass index (BMI)>35 kg/m2. Exclusion criteria were recent active cancer, uncontrolled psychiatric disease or active substance use disorder within 6 months of the initial visit. Referrals to bariatric surgery were assessed within a 5-year follow-up period and compared with baseline referral rates from the Ontario Bariatric Network (OBN). An online survey of 48 endocrinologists in Toronto, Ontario, was also conducted to assess physician-level barriers to referral. RESULTS: The proportion of patients with class II obesity (BMI>35 kg/m2) and type 2 diabetes meeting the eligibility criteria for bariatric referral was 4.6% (n=38). A documented discussion about bariatric surgery occurred with 7 (18.0%) of these eligible patients, and 1 patient (2.6%) was referred for surgery. Aside from surgical referrals, only 2.6% of eligible patients were referred to cognitive-behavioural therapy, 36.8% were initiated on obesity pharmacotherapy and 42.1% were referred to a dietitian. Baseline OBN data demonstrated that most surgical referrals (n=6,360) were from family physicians (65.0%) and only 8.8% were from a medical specialist. Eight percent of surveyed endocrinologists reported that they discussed bariatric surgery with at least half of their eligible patients. The most frequent barrier to discussing bariatric surgery during visits was time constraints. Physicians identified that simplifying the referral process and providing bariatric surgery handouts would be helpful interventions to improve referral rates. CONCLUSIONS: Our gap analysis demonstrated a low bariatric surgery referral rate by tertiary care endocrinologists. Our study also identified a large gap in the appropriate treatment of obesity with poor utilization of behavioural, lifestyle and pharmacotherapy practices. As obesity and diabetes rates increase, better education, training and knowledge translation will be necessary to overcome weight bias and prioritize obesity management.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Adolescente , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/cirurgia , Estudos Retrospectivos , Obesidade/complicações , Obesidade/epidemiologia , Obesidade/cirurgia , Ontário/epidemiologia , Encaminhamento e Consulta
6.
BMC Ecol Evol ; 21(1): 222, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34915861

RESUMO

BACKGROUND: Habitat disturbance affects the biology and health of animals globally. Understanding the factors that contribute to the differential responses of animals to habitat disturbance is critical for conservation. The gut microbiota represents a potential pathway through which host responses to habitat disturbance might be mediated. However, a lack of quantitative environmental data in many gut microbiome (GM) studies of wild animals limits our ability to pinpoint mechanisms through which habitat disturbance affects the GM. Here, we examine the impact of anthropogenic habitat disturbance on the diet and GM of the Critically Endangered black-and-white ruffed lemur (Varecia variegata editorum). We collected fecal samples and behavioral data from Varecia occupying habitats qualitatively categorized as primary forest, moderately disturbed forest, and heavily disturbed forest. RESULTS: Varecia diet and GM composition differed substantially across sites. Dietary richness predicted GM richness across sites, and overall GM composition was strongly correlated to diet composition. Additionally, the consumption of three specific food items positively correlated to the relative abundances of five microbial strains and one microbial genus across sites. However, diet did not explain all of the GM variation in our dataset, and differences in the GM were detected that were not correlated with diet, as measured. CONCLUSIONS: Our data suggest that diet is an important influence on the Varecia GM across habitats and thus could be leveraged in novel conservation efforts in the future. However, other factors such as contact with humans should also be accounted for. Overall, we demonstrate that quantitative data describing host habitats must be paired with GM data to better target the specific mechanisms through which environmental change affects the GM.


Assuntos
Microbioma Gastrointestinal , Lemur , Lemuridae , Animais , Dieta , Ecossistema , Humanos
7.
Biotropica ; 53(4): 994-1003, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34219750

RESUMO

Tropical ecosystems host a large proportion of global biodiversity and directly support the livelihoods of many of the world's poorest, and often marginalized, people through ecosystem goods and services and conservation employment. The coronavirus pandemic has challenged existing conservation structures and management but provides an opportunity to re-examine strategies and research approaches across the tropics to build resilience for future crises. Based on the personal experiences of conservation leaders, managers, and researchers from Madagascar during this period, we discuss the coping strategies of multiple biodiversity conservation organizations during the coronavirus pandemic. We highlight the vital role of local communities in building and maintaining resilient conservation practices that are robust to global disruptions such as the COVID-19 crisis. We argue that the integration of local experts and communities in conservation, research, and financial decision-making is essential to a strong foundation for biodiversity conservation in developing countries to stand up to future environmental, political, and health crises. This integration could be achieved through the support of training and capacity building of local researchers and community members and these actions would also enhance the development of strong, equitable long-term collaborations with international communities. Equipped with such capacity, conservationists and researchers from these regions could establish long-term biodiversity conservation strategies that are adapted to local context, and communities could flexibly balance biodiversity and livelihood needs as circumstances change, including weathering the isolation and financial challenges of local or global crises.

8.
Sci Rep ; 9(1): 16276, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700150

RESUMO

In recent decades Madagascar has experienced significant habitat loss and modification, with minimal understanding of how human land use practices have impacted the evolution of its flora and fauna. In light of ongoing and intensifying anthropogenic pressures, we seek new insight into mechanisms driving genetic variability on this island, using a Critically Endangered lemur species, the black-and-white ruffed lemur (Varecia variegata), as a test case. Here, we examine the relative influence of natural and anthropogenic landscape features that we predict will impose barriers to dispersal and promote genetic structuring across the species range. Using circuit theory, we model functional connectivity among 18 sampling localities using population-based genetic distance (FST). We optimized resistance surfaces using genetic algorithms and assessed their performance using maximum-likelihood population-effects mixed models. The best supported resistance model was a composite surface that included two anthropogenic features, habitat cover and distance to villages, suggesting that rapid land cover modification by humans has driven change in the genetic structure of wild lemurs. Primary conservation priority should be placed on mitigating further forest loss and connecting regions identified as having low dispersal potential to prevent further loss of genetic diversity and promote the survival of other moist forest specialists.


Assuntos
Espécies em Perigo de Extinção , Variação Genética , Genética Populacional , Lemur/genética , Seleção Genética , Animais , Genótipo , Geografia , Humanos , Madagáscar , Tecnologia de Sensoriamento Remoto
9.
Can Fam Physician ; 64(9): e380-e386, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30209111

RESUMO

OBJECTIVE: To explore the experiences, wishes, fears, and beliefs of people who requested and were eligible for medical assistance in dying (MAID) in Canada in the first year after legalization. DESIGN: Qualitative study using semistructured interviews. SETTING: A clinic in Vancouver, BC, that provides MAID. PARTICIPANTS: People requesting and eligible for MAID between February 6 and December 17, 2016. Family and friends who were identified as the patients' primary support people were also interviewed. METHODS: Semistructured interviews were conducted over the telephone, by e-mail, or in person. The interviews were audiorecorded and transcribed and then analyzed using thematic qualitative analysis. The investigators read the transcripts and created a coding scheme to identify themes in the patients' experiences. The identified themes were compiled and evaluated in the context of what is already known based on current literature. Basic demographic characteristics were recorded for context. MAIN FINDINGS: Of the 23 patients whose experiences were explored, most had a malignancy, a neurologic disorder, or organ failure. A main theme was that patients thought it was important to have autonomy and control over their own end-of-life decisions. Main reasons for requesting MAID were a self-perceived unacceptable quality of life, most commonly owing to loss of independence, mobility, ability to communicate, a sense of purpose, and participation in meaningful activity. Some people expressed fear of future suffering and future disability. Pain was seldom mentioned as a cause of suffering. Some participants believed they could discuss their decision with the people in their lives while others chose to keep it a private matter. Most people were not religious. CONCLUSION: The participants' reasons for choosing to pursue MAID were consistent with those of people in other jurisdictions that have been studied. They felt confident in their decision to pursue MAID and did not have fears about the process.


Assuntos
Qualidade de Vida/psicologia , Suicídio Assistido/psicologia , Idoso , Idoso de 80 Anos ou mais , Canadá , Tomada de Decisões , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Suicídio Assistido/legislação & jurisprudência
10.
Can Fam Physician ; 64(9): e387-e393, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30209112

RESUMO

OBJECTIVE: To explore the experience of family and close friends of patients seeking medical assistance in dying (MAID) in Canada. DESIGN: Qualitative study using semistructured interviews. SETTING: A clinic in Vancouver, BC, that provides MAID services. PARTICIPANTS: Eighteen support people for patients seeking MAID. METHODS: Clinic patients seeking MAID identified their primary support people during consultations for an assisted death evaluation. Identified support people were invited to participate in the study, and those who were interested were asked to contact the interviewers. Semistructured interviews were conducted, transcribed, coded, and subjected to content analysis to elucidate common themes. MAIN FINDINGS: All participants were supportive of their loved one's wish for assisted death and they provided emotional and practical support in preparation for MAID. Support persons talked about the journey they went through from their loved one's diagnosis to the MAID request to the actual death. Some were initially opposed but changed their minds after seeing the suffering their loved ones endured. The time before the assisted death involved saying goodbye and, for some, ceremonial rituals (celebration of life, poems, singing, etc). Those interviewed after their loved one's assisted death found the death peaceful and reported that it offered advantages compared with natural death in their loved one's individual circumstances. CONCLUSION: This study provides insight into experiences of support people coping with a loved one who is seeking or has sought MAID in the context of a country unfamiliar with the legal process of a planned and hastened death. Participants were supportive of their loved one's wishes for assistance in death to end suffering and found the process to be peaceful overall.


Assuntos
Adaptação Psicológica , Família/psicologia , Amigos/psicologia , Suicídio Assistido/legislação & jurisprudência , Atitude Frente a Morte , Canadá , Humanos , Entrevistas como Assunto , Pesquisa Qualitativa
11.
Can Fam Physician ; 64(9): e394-e399, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30209113

RESUMO

OBJECTIVE: To explore the experiences of the first cohort of physicians to offer medical assistance in dying (MAID) in British Columbia. DESIGN: Qualitative study using semistructured, one-on-one interviews. SETTING: British Columbia. PARTICIPANTS: Eight physicians who offered MAID in British Columbia in 2016. METHODS: The physicians were interviewed by telephone or by e-mail between 4 and 6 months after MAID was made legal in Canada, with follow-up in January 2017. Interviews were audiorecorded, transcribed, and analyzed through qualitative thematic analysis. MAIN FINDINGS: Participants believed that MAID was rewarding and satisfying work. They explained that some of the structural and emotional challenges related to providing MAID included the following: the refusal of faith-based institutions to provide information about MAID to patients, as well as their refusal to allow assessments or deaths to occur on site; having to deny MAID to patients who did not qualify for it; disagreements with colleagues who did not support the provision of MAID; dealing with the grief of family and friends who were present at the death; and feeling like they were always on call. While a few participants thought that the legislative restrictions of Bill C-14 were appropriate in the beginning when MAID was first available in Canada, most would like to see changes to the legislation to make it more aligned with the intent of the Carter decision, including broadening the eligibility criteria to include mature minors and people with advanced psychiatric diagnoses, having the ability to honour advance directives, and removing the requirement of death being in the reasonably foreseeable future for patients with grievous and irremediable conditions. CONCLUSION: Physicians in this study explained that providing MAID is rewarding work; however, there are many challenges that complicate their ability to offer MAID to patients. The current MAID legislation in Canada should be updated to better serve the needs of patients.


Assuntos
Atitude do Pessoal de Saúde , Médicos/psicologia , Suicídio Assistido/legislação & jurisprudência , Adulto , Colúmbia Britânica , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa
12.
Ecol Evol ; 4(13): 2675-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25077019

RESUMO

Lemurs are among the world's most threatened mammals. The critically endangered black-and-white ruffed lemur (Varecia variegata), in particular, has recently experienced rapid population declines due to habitat loss, ecological sensitivities to habitat degradation, and extensive human hunting pressure. Despite this, a recent study indicates that ruffed lemurs retain among the highest levels of genetic diversity for primates. Identifying how this diversity is apportioned and whether gene flow is maintained among remnant populations will help to diagnose and target conservation priorities. We sampled 209 individuals from 19 sites throughout the remaining V. variegata range. We used 10 polymorphic microsatellite loci and ∼550 bp of mtDNA sequence data to evaluate genetic structure and population dynamics, including dispersal patterns and recent population declines. Bayesian cluster analyses identified two distinct genetic clusters, which optimally partitioned data into populations occurring on either side of the Mangoro River. Localities north of the Mangoro were characterized by greater genetic diversity, greater gene flow (lower genetic differentiation) and higher mtDNA haplotype and nucleotide diversity than those in the south. Despite this, genetic differentiation across all sites was high, as indicated by high average F ST (0.247) and ΦST (0.544), and followed a pattern of isolation-by-distance. We use these results to suggest future conservation strategies that include an effort to maintain genetic diversity in the north and restore connectivity in the south. We also note the discordance between patterns of genetic differentiation and current subspecies taxonomy, and encourage a re-evaluation of conservation management units moving forward.

13.
J Radiol Prot ; 33(1): 163-74, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23295273

RESUMO

The aim of this work is to assess the possible radiological impact on the population of the United Kingdom (UK) from new nuclear power stations proposed for up to eight sites in England and Wales. The radiological impact was measured in terms of collective dose to the UK, European and world populations from a single year's discharge integrated to 500 and 100 000 years and the annual dose to an average member of the UK population (known as the per-caput dose). The doses were calculated for two reactor types, UK EPR™ and AP1000™, using the annual expected discharges estimated by the designers of the reactors and assuming two reactors per site. In addition, typical individual doses to adults living close to the sites were calculated on the basis of continuous discharges for 60 years (the assumed lifetime of the reactors). The dose to a representative person (previously known as the critical group) was not calculated, as this has been done elsewhere. The assessments were carried out using the software program PC-CREAM 08(®) which implements the updated European Commission methodology for assessing the radiological impact of routine releases of radionuclides to the environment. The collective dose truncated to 500 years to the UK population was estimated to be 0.5 manSv assuming UK EPR reactors on all sites and 0.6 manSv assuming AP1000s on three sites with UK EPRs on the other sites. The most significant contribution to the collective dose to the UK population is due to the global circulation of carbon-14 released to the atmosphere. The annual dose to an average member of the UK population from all sites was calculated to be around 10 nSv y(-1) and would therefore contribute little to an individual's total radiation dose. All the calculated doses to a typical adult living near the sites assuming continuous discharges for 60 years were found to be below 1 µSv y(-1).


Assuntos
Contaminação Radioativa do Ar/estatística & dados numéricos , Carga Corporal (Radioterapia) , Exposição Ambiental/estatística & dados numéricos , Centrais Nucleares/estatística & dados numéricos , Monitoramento de Radiação/estatística & dados numéricos , Resíduos Radioativos/estatística & dados numéricos , Radioisótopos/análise , Contaminação Radioativa do Ar/análise , Simulação por Computador , Inglaterra , Exposição Ambiental/análise , Modelos Teóricos , Doses de Radiação , Monitoramento de Radiação/métodos , Resíduos Radioativos/análise , Medição de Risco/métodos , País de Gales
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