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Galaxies in the early Universe that are bright at submillimetre wavelengths (submillimetre-bright galaxies) are forming stars at a rate roughly 1,000 times higher than the Milky Way. A large fraction of the new stars form in the central kiloparsec of the galaxy1-3, a region that is comparable in size to the massive, quiescent galaxies found at the peak of cosmic star-formation history4 and the cores of present-day giant elliptical galaxies. The physical and kinematic properties inside these compact starburst cores are poorly understood because probing them at relevant spatial scales requires extremely high angular resolution. Here we report observations with a linear resolution of 550 parsecs of gas and dust in an unlensed, submillimetre-bright galaxy at a redshift of z = 4.3, when the Universe was less than two billion years old. We resolve the spatial and kinematic structure of the molecular gas inside the heavily dust-obscured core and show that the underlying gas disk is clumpy and rotationally supported (that is, its rotation velocity is larger than the velocity dispersion). Our analysis of the molecular gas mass per unit area suggests that the starburst disk is gravitationally unstable, which implies that the self-gravity of the gas is stronger than the differential rotation of the disk and the internal pressure due to stellar-radiation feedback. As a result of the gravitational instability in the disk, the molecular gas would be consumed by star formation on a timescale of 100 million years, which is comparable to gas depletion times in merging starburst galaxies5.
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The term 'insight' is generically defined in English language as the ability to perceive deeper truths about people and situations. In clinical practice, patient insight is known to have important implications in treatment compliance and clinical outcomes, and can be assessed clinically by looking for the presence of illness awareness, correct attribution of symptoms to underlying condition, and acceptance of treatment. In this article, we suggest that cultivating insight is actually a highly important, yet often overlooked, component of medical training, which may explain why some consistently learn well, communicate effectively, and quickly attain clinical competency, while others struggle throughout their clinical training and may even be difficult to remediate. We herein define 'insight' in the context of medical training as having an astute perception of personal cognitive processes, motivations, emotions, and ability (strengths, weaknesses, and limitations) that should drive self-improvement and effective behavioural regulation. We then describe the utility of cultivating 'insight' in medical training through three lenses of (i) promoting self-regulated, lifelong clinical learning, (ii) improving clinical competencies and person-centred care, and (iii) enhancing physician mental health and well-being. In addition, we review educational pedagogies that are helpful to create a medical eco-system that promotes the cultivation of insight among its trainees and practitioners. Finally, we highlight several tell-tale signs of poor insight and discuss psychological and non-psychological interventions that may help those severely lacking in insight to become more amenable to change and remediation.
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Educação Médica , Aprendizagem , Saúde Mental , Humanos , Competência Clínica , Assistência Centrada no PacienteRESUMO
Subspecialty consultations are becoming highly prevalent in hospital medicine, due to an ageing population with multimorbid conditions and increasingly complex care needs, as well as medicolegal fears that lead to widespread defensive medical practices. Although timely subspecialty consultations in the appropriate clinical context have been found to improve clinical outcomes, there remains a significant proportion of specialty referrals in hospital medicine which are inappropriate, excessive, or do not add value to patient care. In this article, we sought to provide an overview of the common problems pertaining to excessive quantity and suboptimal quality of inpatient subspecialty consultations made in real-world practice and highlight their implications for healthcare financing and patient care. In addition, we discuss the underlying contributing factors that predispose to inappropriate use of the specialist referral system. Finally, we offer a practical, multitiered approach to help rationalize subspecialty consultations, through (i) a systematic model ('WISE' template) for individual referral-making, (ii) development of standardized healthcare institutional referral guidelines with routine clinical audits for quality control, (iii) adopting an integrated generalist care model, and (iv) incorporating training on effective referral-making in medical education.
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Providing family updates is a common clinical task for medical trainees and practitioners working in hospital settings. Good clinical communication skills are essential in clinical care as it is associated with improved patient satisfaction, understanding of condition, treatment adherence, and better overall clinical outcomes. Moreover, poor communications are often the source of medical complaints. However, while patient-centred communication skills training has generally been incorporated into clinical education, there hitherto remains inadequate training on clinical communications with patients' families, which carry different nuances. In recent years, it is increasingly recognized that familial involvement in the care of hospitalized patients leads to better clinical and psychological outcomes. In fact, in Asian populations with more collectivistic cultures, families are generally highly involved in patient care and decision-making. Therefore, effective clinical communications and regular provision of family updates are essential to build therapeutic rapport, facilitate familial involvement in patient care, and also provide a more holistic understanding of the patient's background and psychosocial set-up. In this article, we herein describe a seven-step understand the clinical context, gather perspectives, deliver medical information, address questions, concerns and expectations, provide tentative plans, demonstrate empathy, postcommunication reflections model as a practical guide for medical trainees and practitioners in provision of structured and effective family updates in their clinical practice.
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Comunicação , Relações Profissional-Família , Humanos , Competência Clínica , Empatia , Família/psicologia , Relações Médico-PacienteRESUMO
Clinical reasoning is a crucial skill and defining characteristic of the medical profession, which relates to intricate cognitive and decision-making processes that are needed to solve real-world clinical problems. However, much of our current competency-based medical education systems have focused on imparting swathes of content knowledge and skills to our medical trainees, without an adequate emphasis on strengthening the cognitive schema and psychological processes that govern actual decision-making in clinical environments. Nonetheless, flawed clinical reasoning has serious repercussions on patient care, as it is associated with diagnostic errors, inappropriate investigations, and incongruent or suboptimal management plans that can result in significant morbidity and even mortality. In this article, we discuss the psychological constructs of clinical reasoning in the form of cognitive 'thought processing' models and real-world contextual or emotional influences on clinical decision-making. In addition, we propose practical strategies, including pedagogical development of a personal cognitive schema, mitigating strategies to combat cognitive bias and flawed reasoning, and emotional regulation and self-care techniques, which can be adopted in medical training to optimize physicians' clinical reasoning in real-world practice that effectively translates learnt knowledge and skill sets into good decisions and outcomes.
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During drought, plants allocate resources to aboveground biomass production and belowground carbohydrate reserves, often at the expense of production of defence traits. Additionally, drought has been shown to alter floral resources, with potential implications for plant-pollinator interactions. Although soil symbionts, such as arbuscular mycorrhizal (AM) fungi, can alleviate drought stress in plants, certain levels of drought may negatively impact this relationship, with potential cascading effects. Because of their importance to plant and animal community diversity, we examined effects of drought on biomass production, physical defence properties, nectar production, and associated AM fungal abundance of five common prairie forb species in a greenhouse study. Reduced soil moisture decreased vegetative biomass production. Production of trichomes and latex decreased under drought, relative to well-watered conditions. Ruellia humilis flowers produced less nectar under drought, relative to well-watered conditions. Intra-radical AM fungal colonization was not significantly affected by drought, although extra-radical AM fungal biomass associated with S. azurea decreased following drought. Overall, grassland forb productivity, defence, and nectar production were negatively impacted by moderate drought, with possible negative implications for biotic interactions. Reduced flower and nectar production may lead to fewer pollinator visitors, which may contribute to seed limitation in forb species. Reduced physical defences increase the likelihood of herbivory, further decreasing the ability to store energy for essential functions, such as reproduction. Together, these results suggest drought can potentially impact biotic interactions between plants and herbivores, pollinators, and soil symbionts, and highlights the need for direct assessments of these relationships under climate change scenarios.
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Micorrizas , Animais , Herbivoria , Néctar de Plantas , Pradaria , Secas , Água , SoloRESUMO
The fungicide benomyl was the most commonly used biocide for both field and greenhouse experiments in which arbuscular mycorrhizal fungal (AMF) suppression is desired. Unfortunately benomyl is no longer manufactured and therefore is not available for experimental use and no fungicide has been proposed as a successful alternative for experimentally suppressing mycorrhizal fungi. In this study we examined the potential for the fungicide Topsin M (topsin) to suppress mycorrhizal symbiosis in both field and greenhouse experiments. Topsin reduced AMF colonization of the obligately mycotrophic, warm-season grass Andropogon gerardii with a large and significant reduction in plant biomass production. Topsin reduced AMF colonization of the facultatively mycotrophic, cool-season grass Pascopyron smithii but did not significantly reduce biomass production. Fertilization with nitrogen and phosphorus was able to compensate for reductions in biomass due to the application of fungicide because biomass production of plants that received topsin fungicide was not significantly different from fertilized controls not receiving topsin. While we are not advocating that topsin fungicide is a universal mechanism for mycorrhizal-suppressed controls, in systems where benomyl was found to be successful topsin appears to be a useful, available and successful alternative.
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Benomilo/análogos & derivados , Benomilo/farmacologia , Fungicidas Industriais/farmacologia , Micorrizas/efeitos dos fármacos , Microbiologia do Solo , Biomassa , Micorrizas/fisiologia , Poaceae/efeitos dos fármacos , Poaceae/microbiologia , Poaceae/fisiologia , Simbiose/efeitos dos fármacosRESUMO
Microwave Kinetic Inductance Detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the development of feedhorn-coupled MKID detectors for the TolTEC millimeter-wave imaging polarimeter being constructed for the 50-meter Large Millimeter Telescope (LMT). Observations with TolTEC are planned to begin in early 2019. TolTEC will comprise â¼7,000 polarization sensitive MKIDs and will represent the first MKID arrays fabricated and deployed on monolithic 150 mm diameter silicon wafers - a critical step towards future large-scale experiments with over 105 detectors. TolTEC will operate in observational bands at 1.1, 1.4, and 2.0 mm and will use dichroic filters to define a physically independent focal plane for each passband, thus allowing the polarimeters to use simple, direct-absorption inductive structures that are impedance matched to incident radiation. This work is part of a larger program at NIST-Boulder to develop MKID-based detector technologies for use over a wide range of photon energies spanning millimeter-waves to X-rays. We present the detailed pixel layout and describe the methods, tools, and flexible design parameters that allow this solution to be optimized for use anywhere in the millimeter and sub-millimeter bands. We also present measurements of prototype devices operating in the 1.1 mm band and compare the observed optical performance to that predicted from models and simulations.
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The interaction of one of the two DNA methyltransferases encoded by the HgaI restriction and modification system, M.HgaI-2, with substrates and substrate analogues is described. Circular dichroism spectroscopy has been used to demonstrate that addition of the methyl donor, S-adenosyl-L-methionine and the inhibitory substrate analogue sinefungin, both induce conformational transitions in the protein in the absence of DNA. Moreover, the addition of DNA is shown to enhance the apparent secondary structure of M.HgaI-2 whilst addition of sinefungin or S-adenosyl-L-methionine reduces apparent secondary structure. The circular dichroism spectrum of the abortive complex between the enzyme, DNA and sinefungin is dominated by the conformational properties of the binary complex of enzyme and sinefungin alone. Addition of a specific oligodeoxynucleotide duplex in which the target cytosine is replaced by a pyrimidinone, leads to a further ligand induced conformational transition as determined by electrophoretic analysis. The addition of sinefungin, or S-adenosyl-L-methionine, to M.HgaI-2 bound to the reactive oligodeoxynucleotide duplex, leads to yet another conformational transition in the protein as determined by the differential susceptibility of ternary and binary complexes to proteolysis. These experiments identify at least six ligand-inducible conformational states of M.HgaI-2 and, in view of the sequence similarity amongst this class of enzymes, suggest that conformational flexibility is a general feature of C-5 cytosine-specific DNA methyltransferases. Moreover, the substitution of the target cytosine by a pyrimidinone mimics the effect of 5-azacytosine incorporation into DNA.
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DNA-Citosina Metilases/química , Estrutura Secundária de Proteína , Adenosina/análogos & derivados , Adenosina/farmacologia , Sequência de Aminoácidos , Sequência de Bases , Dicroísmo Circular , DNA/metabolismo , DNA-Citosina Metilases/efeitos dos fármacos , DNA-Citosina Metilases/genética , Ligantes , Dados de Sequência Molecular , S-Adenosilmetionina/farmacologiaRESUMO
Granular/vesicular transport is thought to be supported by microtubule-based force-generating adenosine triphosphatases such as kinesin. Kinesin is a motor molecule that has been well studied in brain and other neuronal tissues. Although vesicular transport is important for pancreatic beta-cell secretory activities, the role of kinesin in beta-cell function has not been investigated. It is hypothesized that kinesin functions as a translocator that associates with both microtubules and insulin-containing granules in beta-cells and transports the secretory granules from deep within the cytoplasm, where insulin is synthesized and processed, to the surface of beta-cells upon secretory stimulation. To test this hypothesis, a mouse beta-cell kinesin heavy chain complementary DNA was cloned and sequenced. Kinesin expression in primary cultures of mouse beta-cells then was selectively suppressed by antimouse beta-cell kinesin heavy chain antisense oligonucleotide treatment. Analysis of insulin secretion determined that the basal level of insulin secretion from the treated cells was decreased by 50%. Furthermore, glucose-stimulated insulin release from treated beta-cells was reduced by almost 70% after suppression of kinesin expression by antisense treatment. The findings from this study provide the first direct evidence that kinesin, a microtubule-based motor protein, plays an important role in insulin secretion.
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Expressão Gênica/efeitos dos fármacos , Insulina/metabolismo , Ilhotas Pancreáticas/enzimologia , Ilhotas Pancreáticas/metabolismo , Cinesinas/genética , Oligonucleotídeos Antissenso/farmacologia , Animais , Sequência de Bases , Células Cultivadas , DNA Complementar/isolamento & purificação , Glucose/farmacologia , Insulina/biossíntese , Secreção de Insulina , Ilhotas Pancreáticas/ultraestrutura , Camundongos , Microscopia Eletrônica , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Oligonucleotídeos Antissenso/metabolismoRESUMO
Symbiotic associations between plants and arbuscular mycorrhizal (AM) fungi are ubiquitous in many herbaceous plant communities and can have large effects on these communities and ecosystem processes. The extent of species-specificity between these plant and fungal symbionts in nature is poorly known, yet reciprocal effects of the composition of plant and soil microbe communities is an important assumption of recent theoretical models of plant community structure. In grassland ecosystems, host plant species may have an important role in determining development and sporulation of AM fungi and patterns of fungal species composition and diversity. In this study, the effects of five different host plant species [Poa pratensis L., Sporobolus heterolepis (A. Gray) A. Gray, Panicum virgatum L., Baptisia bracteata Muhl. ex Ell., Solidago missouriensis Nutt.] on spore communities of AM fungi in tallgrass prairie were examined. Spore abundances and species composition of fungal communities of soil samples collected from patches within tallgrass prairie were significantly influenced by the host plant species that dominated the patch. The AM fungal spore community associated with B. bracteata showed the highest species diversity and the fungi associated with Pa. virgatum showed the lowest diversity. Results from sorghum trap cultures using soil collected from under different host plant species showed differential sporulations of AM fungal species. In addition, a greenhouse study was conducted in which different host plant species were grown in similar tallgrass prairie soil. After 4 months of growth, AM fungal species composition was significantly different beneath each host species. These results strongly suggest that AM fungi show some degree of host-specificity and are not randomly distributed in tallgrass prairie. The demonstration that host plant species composition influences AM fungal species composition provides support for current feedback models predicting strong regulatory effects of soil communities on plant community structure. Differential responses of AM fungi to host plant species may also play an important role in the regulation of species composition and diversity in AM fungal communities.
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In tallgrass prairie, plant species interactions regulated by their associated mycorrhizal fungi may be important forces that influence species coexistence and community structure; however, the mechanisms and magnitude of these interactions remain unknown. The objective of this study was to determine how interspecific competition, mycorrhizal symbiosis, and their interactions influence plant community structure. We conducted a factorial experiment, which incorporated manipulations of abundance of dominant competitors, Andropogon gerardii and Sorghastrum nutans, and suppression of mycorrhizal symbiosis using the fungicide benomyl under two fire regimes (annual and 4-year burn intervals). Removal of the two dominant C4 grass species altered the community structure, increased plant species richness, diversity, and evenness, and increased abundance of subdominant graminoid and forb species. Suppression of mycorrhizal fungi resulted in smaller shifts in community structure, although plant species richness and diversity increased. Responses of individual plant species were associated with their degree of mycorrhizal responsiveness: highly mycorrhizal responsive species decreased in abundance and less mycorrhizal responsive species increased in abundance. The combination of dominant-grass removal and mycorrhizal suppression treatments interacted to increase synergistically the abundance of several species, indicating that both processes influence species interactions and community organization in tallgrass prairie. These results provide evidence that mycorrhizal fungi affect plant communities indirectly by influencing the pattern and strength of plant competitive interactions. Burning strongly influenced the outcome of these interactions, which suggests that plant species diversity in tallgrass prairie is influenced by a complex array of interacting processes, including both competition and mycorrhizal symbiosis.
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Greenhouse experiments were conducted to examine the impact of expanded clay (Turface) or porous ceramic (Isolite) amendments on germination, biomass production, plant Zn concentration, and Zn accumulation by Festuca arundinacea grown in mine tailings. Because previous studies have demonstrated that fertilization is essential for plant growth in these tailings, manure was also added to the tailings. Plant growth and germination were greatest if the expanded clay was added topically to the tailings. To a lesser extent, plant growth and germination was also stimulated by topical additions of porous ceramic. However, no benefit was observed if either amendment was mixed into the top 10 cm of the mine tailings. The concentration of Zn in F. arundinacea tissues was lowest if the expanded clay was added topically to the mine tailings. Roots growing in the layer of clay or ceramic amendment appeared to be smaller, finer, and more abundant than the large, coarse roots found throughout the tailings-manure mixture. These results suggest that topical application of an expanded clay or porous ceramic product will increase seed germination and improve plant establishment and growth in contaminated minespoils.
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Biomass production of Andropogon gerardii and Festuca arundinacea was assessed in mine tailings (chat), a material containing high levels of zinc. The effects of organic and inorganic fertilizer amendments, the addition of an expanded clay material, and mycorrhizal fungi on the revegetation of chat were assessed. Plant growth in chat was best with mycorrhizal inoculation combined with nitrogen (either organic or inorganic) and phosphorus fertilization. Plant growth was also achieved if the chat material was amended with expanded clay and N and P fertilizer. However, the biomass produced in contaminated soil did not equal that of similarly fertilized uncontaminated soil. Regression analysis and canonical discriminate analysis revealed significant differences in the responses of the two plant species to the various chat amendments. Although F. arundinacea generally produced greater biomass than A. gerardii, it tended to accumulate more zinc in the shoots than A. gerardii. Therefore, if plant cover is to be used as forage or if wind-blown plant dry matter is of concern, A. gerardii may be more appropriate than F. arundinacea for revegetation of these toxic sites. Alternatively, if maximum plant cover is of primary importance to reduce wind or water erosion from contaminated soils, F. arundinacea may be the species of choice.
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The influence of exposure to exogenous estradiol on the interval from parturition to first ovulation, luteinizing hormone (LH) secretion and luteal function was examined in cows. Cows were assigned at parturition to one of three treatments. Cows received either a 3.0 (1-E; n = 30) or .75 cm (1/4-E; n = 28) implant containing 17 beta-estradiol or served as untreated control animals (C; n = 33). Implants were administered within 2 days following parturition and removed on day 40 postpartum (day 0 = day of parturition). Single blood samples were collected twice weekly and analyzed for progesterone to determine length of postpartum anestrus and duration of the initial increase in progesterone. Sequential blood samples were collected on day 35 +/- .1 postpartum (15 min intervals for 18 hrs) from 5 cows in each treatment and analyzed for LH. Concentrations of estradiol were higher (P less than .01) in the 1-E (5.3 +/- .24) than in C (3.9 +/- .23) or 1/4 E (3.9 +/- .25) cows on day 35 postpartum. The interval from parturition to the first estrous cycle of normal duration was similar for cows in the C and 1-E treatment (53 +/- 2.4 and 56 +/- 2.4 days, respectively). Cows in the 1/4-E treatment had a longer (P less than .05) interval (68 +/- 2.5 days). Secretion of LH was similar among treatments on day 35 postpartum. The first normal luteal phase after parturition was preceded by a transient rise in progesterone in 81, 64 and 85% of the cows in the C, 1-E and 1/4-E treatments, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anestro/efeitos dos fármacos , Bovinos/fisiologia , Estradiol/farmacologia , Estro/efeitos dos fármacos , Período Pós-Parto/efeitos dos fármacos , Animais , Corpo Lúteo/efeitos dos fármacos , Implantes de Medicamento , Estradiol/administração & dosagem , Estradiol/sangue , Feminino , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Gravidez , Distribuição AleatóriaRESUMO
The costs of warble fly in cattle have been estimated at 35 million pounds for Great Britain in 1985 and $85 million for Italy in 1982. Control measures within the European Community vary from one country to another and from the voluntary application of systemic products by individual farmers to comprehensive national eradication schemes backed by legislation. Of the countries opting for national eradication measures, Denmark has been successful and the Federal Republic of Germany, the Netherlands, the Republic of Ireland, Northern Ireland and Great Britain have reduced the incidence of the disease to very low levels. In Great Britain in 1978, 38 per cent of cattle were found to be affected in a survey of selected fatstock markets by the Meat and Livestock Commission. In 1985 the incidence had fallen to 0.01 per cent. Seven hundred and five affected herds were found in Great Britain when the disease was made notifiable in 1982, falling to 419 affected herds in 1985. Treatment of all cattle over 12 weeks old is required in affected herds. Since 1982 parts of Great Britain where the disease has persisted or where there is evidence of a recrudescence have been designated 'infected areas' in which all cattle over 12 weeks old have been required to be treated within specific dates. In addition to statutory measures the control measures in Great Britain include the inspection of cattle at auction markets and on farms. Work on the application to field conditions of an ELISA test is in progress, with encouraging results. It is considered that Great Britain is now well placed to eradicate warble fly.
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Doenças dos Bovinos/prevenção & controle , Dípteros , Hipodermose/veterinária , Controle de Insetos , Animais , Bovinos , Doenças dos Bovinos/parasitologia , União Europeia , Hipodermose/prevenção & controle , Reino UnidoRESUMO
The neurotropic disease of pigeons caused by a variant avian paramyxovirus type 1 virus was confirmed in 866 lofts in Great Britain during 1984, in comparison with 192 lofts during July to December 1983. The 1984 outbreaks were spread over 48 counties in England and Wales and three regions in Scotland. The main methods of spread of disease in the 1984 outbreaks appeared to be similar to 1983 with 574 of 866 probably resulting from contact with infected birds at, or travelling to, races or shows. In 791 of 866 (92.5 per cent) outbreaks in 1984 disease was seen only in unvaccinated birds. A further 61 (7 per cent) occurred in inadequately vaccinated birds or birds vaccinated after clinical signs appeared.
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Doenças das Aves/epidemiologia , Columbidae , Surtos de Doenças/veterinária , Infecções por Respirovirus/veterinária , Animais , Doenças das Aves/prevenção & controle , Galinhas , Paramyxoviridae/patogenicidade , Infecções por Respirovirus/epidemiologia , Infecções por Respirovirus/prevenção & controle , Estações do Ano , Reino Unido , Vacinação/veterináriaRESUMO
During July to December 1983 birds in 192 racing pigeon lofts were confirmed as infected with paramyxovirus type 1 virus on the basis of disease signs alone when contact with infected cases was known (10) or with supporting serology (130), virus isolation (eight) or both (44). These outbreaks were mainly concentrated in south Wales (89) and Dorset (40). In all, 29 counties of Great Britain were involved. In the majority of outbreaks (69 per cent) activities associated with racing were strongly implicated in the spread of the disease but trade in birds, stray bird contact, loft visits and contact at shows were also possible methods of spread. Although considerable variation was seen in the pathogenicity of the viruses isolated from affected birds there were no apparent epizootiological links between isolates of similar virulence.