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1.
Mol Ecol ; 33(3): e17230, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38078558

RESUMO

Urbanization is a persistent and widespread driver of global environmental change, potentially shaping evolutionary processes due to genetic drift and reduced gene flow in cities induced by habitat fragmentation and small population sizes. We tested this prediction for the eastern grey squirrel (Sciurus carolinensis), a common and conspicuous forest-dwelling rodent, by obtaining 44K SNPs using reduced representation sequencing (ddRAD) for 403 individuals sampled across the species' native range in eastern North America. We observed moderate levels of genetic diversity, low levels of inbreeding, and only a modest signal of isolation-by-distance. Clustering and migration analyses show that estimated levels of migration and genetic connectivity were higher than expected across cities and forested areas, specifically within the eastern portion of the species' range dominated by urbanization, and genetic connectivity was less than expected within the western range where the landscape is fragmented by agriculture. Landscape genetic methods revealed greater gene flow among individual squirrels in forested regions, which likely provide abundant food and shelter for squirrels. Although gene flow appears to be higher in areas with more tree cover, only slight discontinuities in gene flow suggest eastern grey squirrels have maintained connected populations across urban areas in all but the most heavily fragmented agricultural landscapes. Our results suggest urbanization shapes biological evolution in wildlife species depending strongly on the composition and habitability of the landscape matrix surrounding urban areas.


Assuntos
Animais Selvagens , Metagenômica , Animais , Humanos , População Urbana , Ecossistema , Sciuridae/genética
2.
Biol Lett ; 19(3): 20220555, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36987612

RESUMO

Diel patterns in foraging activity are dictated by a combination of abiotic, biotic and endogenous limits. Understanding these limits is important for insects because ectotherm taxa will respond more pronouncedly to ongoing climatic change, potentially affecting crucial ecosystem services. We leverage an experimental macrocosm, the Montreal Insectarium Grand Vivarium, to test the importance of endogenous mechanisms in determining temporal patterns in foraging activity of butterflies. Specifically, we assessed the degree of temporal niche partitioning among 24 butterfly species originating from the Earth's tropics within controlled environmental conditions. We found strong niche overlap, with the frequency of foraging events peaking around solar noon for 96% of the species assessed. Our models suggest that this result was not due to the extent of cloud cover, which affects radiational heating and thus limits body temperature in butterflies. Together, these findings suggest that an endogenous mechanism evolved to regulate the timing of butterfly foraging activity within suitable environmental conditions. Understanding similar mechanisms will be crucial to forecast the effects of climate change on insects, and thus on the many ecosystem services they provide.


Assuntos
Borboletas , Ecossistema , Animais , Borboletas/fisiologia , Mudança Climática
3.
Can J Psychiatry ; 63(3): 182-196, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29513631

RESUMO

This paper has been substantially revised by the Canadian Psychiatric Association's Research Committee and approved for republication by the CPA's Board of Directors on May 3, 2017. The original policy paper1 was developed by the Scientific and Research Affairs Standing Committee and approved by the Board of Directors on November 10, 2008.


Assuntos
Guias como Assunto/normas , Meios de Comunicação de Massa/normas , Psiquiatria/normas , Sociedades Médicas/normas , Suicídio , Canadá , Humanos
7.
BMC Med Ethics ; 14: 6, 2013 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-23402260

RESUMO

BACKGROUND: In 2009, Dr. Paolo Zamboni proposed chronic cerebrospinal venous insufficiency (CCSVI) as a possible cause of multiple sclerosis (MS). Although his theory and the associated treatment ("liberation therapy") received little more than passing interest in the international scientific and medical communities, his ideas became the source of tremendous public and political tension in Canada. The story moved rapidly from mainstream media to social networking sites. CCSVI and liberation therapy swiftly garnered support among patients and triggered remarkable and relentless advocacy efforts. Policy makers have responded in a variety of ways to the public's call for action. DISCUSSION: We present three different perspectives on this evolving story, that of a health journalist who played a key role in the media coverage of this issue, that of a health law and policy scholar who has closely observed the unfolding public policy developments across the country, and that of a medical ethicist who sits on an expert panel convened by the MS Society of Canada and the Canadian Institutes of Health Research to assess the evidence as it emerges. SUMMARY: This story raises important questions about resource allocation and priority setting in scientific research and science policy. The growing power of social media represents a new level of citizen engagement and advocacy, and emphasizes the importance of open debate about the basis on which such policy choices are made. It also highlights the different ways evidence may be understood, valued and utilized by various stakeholders and further emphasizes calls to improve science communication so as to support balanced and informed decision-making.


Assuntos
Medicina Baseada em Evidências , Alocação de Recursos para a Atenção à Saúde , Política de Saúde , Esclerose Múltipla/etiologia , Esclerose Múltipla/terapia , Defesa do Paciente , Formulação de Políticas , Política , Mídias Sociais , Insuficiência Venosa/complicações , Angioplastia com Balão/efeitos adversos , Encéfalo/irrigação sanguínea , Canadá , Ensaios Clínicos como Assunto/economia , Ensaios Clínicos como Assunto/ética , Tomada de Decisões , Humanos , Apoio à Pesquisa como Assunto , Saskatchewan , Coluna Vertebral/irrigação sanguínea , Stents/efeitos adversos
8.
Sci Data ; 9(1): 109, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35347145

RESUMO

Mass media plays an important role in the construction and circulation of risk perception associated with animals. Widely feared groups such as spiders frequently end up in the spotlight of traditional and social media. We compiled an expert-curated global database on the online newspaper coverage of human-spider encounters over the past ten years (2010-2020). This database includes information about the location of each human-spider encounter reported in the news article and a quantitative characterisation of the content-location, presence of photographs of spiders and bites, number and type of errors, consultation of experts, and a subjective assessment of sensationalism. In total, we collected 5348 unique news articles from 81 countries in 40 languages. The database refers to 211 identified and unidentified spider species and 2644 unique human-spider encounters (1121 bites and 147 as deadly bites). To facilitate data reuse, we explain the main caveats that need to be made when analysing this database and discuss research ideas and questions that can be explored with it.


Assuntos
Picada de Aranha , Venenos de Aranha , Aranhas , Animais , Bases de Dados Factuais , Humanos , Idioma , Jornais como Assunto
9.
Curr Biol ; 32(16): R871-R873, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35998593

RESUMO

In the internet era, the digital architecture that keeps us connected and informed may also amplify the spread of misinformation. This problem is gaining global attention, as evidence accumulates that misinformation may interfere with democratic processes and undermine collective responses to environmental and health crises1,2. In an increasingly polluted information ecosystem, understanding the factors underlying the generation and spread of misinformation is becoming a pressing scientific and societal challenge3. Here, we studied the global spread of (mis-)information on spiders using a high-resolution global database of online newspaper articles on spider-human interactions, covering stories of spider-human encounters and biting events published from 2010-20204. We found that 47% of articles contained errors and 43% were sensationalist. Moreover, we show that the flow of spider-related news occurs within a highly interconnected global network and provide evidence that sensationalism is a key factor underlying the spread of misinformation.


Assuntos
Mídias Sociais , Aranhas , Animais , Comunicação , Ecossistema , Humanos , Aranhas/fisiologia
10.
Paediatr Child Health ; 21(5): 237-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441013
11.
Insects ; 12(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34680690

RESUMO

In general, insects and arthropods polarizing: they either fascinate people, disgust people, or both, and they generate lots of questions. Museums are perceived as reliable sources of information and, as such, a go-to destination for the public to receive answers. Since its opening in 1990, the Montreal Insectarium has offered an entomological information service, allowing the public to send questions, photographs, and specimens for identification. All requests are answered by entomologists. Spatiotemporal variations in taxonomic, geographic, and thematic profiles of the 4163 requests received in 2010-2011 and 2017-2018 were analyzed. Requests came from 35 countries, and most of those requests came from Canada. The majority of requests were identification requests. Representing 25% of identification requests, the five most frequent species were the eastern dobsonfly Corydalus cornutus, the masked hunter Reduvius personatus, the giant water bug Lethocerus americanus, the western conifer-seed bug Leptoglossus occidentalis, and the Japanese beetle Popillia japonica. A comparison with the data from the citizen science platform iNaturalist shows that the EIS can be a valuable tool for invasive species detection. Frequent subjects included school projects, entomophagy (eating insects), and wasp and bee nests. Finally, we discuss the role of entomologists in providing scientific information but also in addressing common concerns regarding cohabitation with arthropods.

13.
Can J Public Health ; 107(3): e330-e332, 2016 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-27763851

RESUMO

Media reporting on suicide may have harmful and/or protective effects on deaths by suicide, depending on the nature of the coverage. Canada's first forum on this important issue was held in Toronto on November 6, 2015. Participating in the forum were public health policy-makers, mental health and suicide prevention experts and senior media representatives. This commentary summarizes the content of the forum and highlights the need for ongoing collaboration between suicide prevention experts and media professionals aimed at safe and respectful reporting that maintains the public's need to be informed.


Assuntos
Meios de Comunicação de Massa , Prevenção do Suicídio , Canadá , Congressos como Assunto , Humanos
14.
Int J Health Serv ; 35(3): 603-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16119578

RESUMO

Gary Schwitzer, former medical correspondent at CNN and now a professor of journalism, listed "10 troublesome trends in TV health news," making the important point that most people today get their health information from the media, and from TV in particular. In this article, the author presents Schwitzer's list and expands it with 10 more troublesome trends. Good health reporting should provide a straightforward, balanced, comprehensible summary of health issues that provides context to information-hungry consumers; it should rarely be sensational, but always skeptical. And there should be a lot more of it.


Assuntos
Jornalismo Médico/normas , Meios de Comunicação de Massa/normas , Editoração/normas , Televisão/normas , Humanos , Política , Viés de Publicação , Reino Unido , Estados Unidos
15.
Dev Growth Differ ; 24(2): 155-162, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-37281590

RESUMO

The drugs, fluphenazine, chlorpromazine, dibucaine, propranolol, vinblastine and W7[N-(6-arninohexyl)-5 chloro-1-napthalene-sulfonamide], which have been shown to prevent formation of the ternary activated complex of Ca++ -calmodulin with several soluble or membrane proteins, inhibit the cortical reaction induced by fertilization, by ionophore A 23187 or by the microinjection of Ca++ buffers when applied from outside to sea urchin eggs. In contrast, direct intracellular microinjection of these drugs, even at concentrations much exceeding their I50 for external application, does not suppress elevation of the fertilization membrane, although it prevents cleavage after fertilization. The implication is that intracellular calmodulin is not the receptor of Ca++ in the Ca++ -dependent exocytosis of cortical granules induced by fertilization, by ionophore, or by the micro-injection of calcium buffers.

16.
Dev Growth Differ ; 30(2): 197-207, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37282239

RESUMO

In starfish, the activity of a major Ca2+ -and cyclic nuleotide-independent protein kinase has been shown to fluctuate in phase with that of MPF along meiotic and mitotic cell cycle (23, 25). Microinjection of α-naphthylphosphate (α-NP), a potent phosphatase inhibitor, increased considerably (from 15 to 546 picomoles/min/mg protein) the activity of this major cycling kinase in homogenates. Although this result supported the view that kinase phosphorylation might induce its own activation, this hypothesis was eliminated because injection of cytoplasm from hormone-stimulated enucleated oocytes, which contained the fully activated kinase but no MPF, failed to trigger kinase activation in recipient oocytes. In contrast, kinase activation was induced in recipient oocytes injected with either cytoplasm taken from nucleated maturing oocytes, which contained high MPF and kinase activities, or cytoplasm taken later from hormone-stimulated and ATP-γ-S-injected oocytes which contained high MPF but low kinase activites. These results indicate that inhibiting dephosphorylation of some regulatory protein activates the M-phase-specific protein kinase. The possibility that the M-phase or maturation-promoting factor (MPF) might be this regulatory protein is discussed.

17.
Dev Growth Differ ; 27(3): 251-262, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-37281094

RESUMO

Single nuclei (germinal vesicles) manually isolated from large oocytes of the starfish Echinaster sepositus, as well as the complementary anucleated oocytes, were used to investigate the early changes of protein phosphorylation which occur from 1-MeAde addition to germinal vesicle breakdown (GVBD). Stimulation of protein phosphorylation was already evident in the nucleus shortly after 1-MeAde addition (18 min, thus about 0.40x the time required for GVBD), although it began first in the cytoplasm. No translocation of phosphoprotein across the nuclear envelope was detected before GVBD. Presence of the nucleus is not required for the hormone to stimulate protein phosphorylation in the remaining part of the oocytetin:fact the patterns of protein phosphorylation in enucleated oocytes were found to be identical, whether enucleation was performed after or before hormonal treatment. Cytoplasm taken at the time of GVBD from maturing Echinaster oocytes induces meiotic maturation when transferred in stage VI immature oocytes of the amphibian Xenopus laevis.

18.
Dev Growth Differ ; 29(1): 93-103, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37281399

RESUMO

Many studies suggest that MPF activation depends on protein phosphorylation or that MPF is itself a protein kinase. In the present report, cyclic variations of MPF activity have been correlated in vivo with changes in the extent of protein phosphorylation or in vitro with changes of a major protein kinase during the first cell cycles of fertilized starfish eggs. This cycling protein kinase neither requires cAMP nor Ca2+ . Neither colchicine nor aphidicoline, which inhibits cleavage and chromosome replication respectively, was found to suppress the synchronous and cyclic variations of both MPF and protein kinase activities. Protein synthesis was found to be required for both MPF and protein kinase activities to reappear after their simultaneous drop at the time of mitotic or meiotic cleavages. Production of either MPF or protein kinase activities is not the immediate result of protein synthesis since there is a delay at each cell cycle between the time when protein synthesis is required and the time when both MPF and protein kinase activities are produced. This suggests that both MPF and protein kinase activities might involve some post-translational modification of a precursor protein synthesized during the preceeding cell cycle.

19.
Toxicol Sci ; 73(1): 141-8, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12700411

RESUMO

Methoxychlor, lindane, and dieldrin are organochlorine pesticides that have been described as altering different reproductive functions in mammals and in invertebrates. However, few data have been published concerning the effects these pesticides have on oocyte maturation and fertilization. The aim of this study was to determine whether these compounds could affect maturation of mouse and starfish oocytes. We observed that germinal vesicle breakdown (GVBD) in starfish oocytes was significantly inhibited by the pesticides. Furthermore, formation of the first meiotic spindle and extrusion of the first polar body were also altered in mouse as well as in starfish. Our results suggest that the three pesticides act on common intracellular targets in invertebrates as well as in vertebrates.


Assuntos
Inseticidas/toxicidade , Oócitos/crescimento & desenvolvimento , Estrelas-do-Mar/crescimento & desenvolvimento , Animais , Dieldrin/toxicidade , Feminino , Imunofluorescência , Hexaclorocicloexano/toxicidade , Técnicas In Vitro , Meiose/efeitos dos fármacos , Metoxicloro/toxicidade , Camundongos , Oócitos/efeitos dos fármacos , Fuso Acromático/efeitos dos fármacos , Fixação de Tecidos
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