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1.
Vet Clin North Am Food Anim Pract ; 40(2): 219-232, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38395704

RESUMO

The threat of foreign animal diseases is steadily increasing. Veterinary practitioners play a vital role in a community's preparedness for, response to, and recovery from a foreign animal disease outbreak. This article examines the steps a practitioner needs to take to become ready to have a role in disaster readiness and response. Resources exist to provide the practitioner with tools needed to transition their normal daily activities to a larger integrated response. The knowledge and skills used by practitioners in disaster management lead to a more effective and efficient response to a foreign animal disease.


Assuntos
Médicos Veterinários , Animais , Medicina Veterinária , Planejamento em Desastres , Surtos de Doenças/veterinária , Surtos de Doenças/prevenção & controle , Doenças dos Animais/prevenção & controle , Humanos
2.
Animals (Basel) ; 12(3)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35158590

RESUMO

Sensor technologies can identify modified animal activity indicating changes in health status. This study investigated sheep behavior before and after illness caused by mold-contaminated feed using tri-axial accelerometers. Ten ewes were fitted with HerdDogg biometric accelerometers. Five ewes were concurrently fitted with Axivity AX3 accelerometers. The flock was exposed to mold-contaminated feed following an unexpected ration change, and observed symptomatic ewes were treated with a veterinarian-directed protocol. Accelerometer data were evaluated 4 days before exposure (d -4 to -1); the day of ration change (d 0); and 4 days post exposure (d 1 to 4). Herddogg activity index correlated to the variability of minimum and standard deviation of motion intensity monitored by the Axivity accelerometer. Herddogg activity index was lower (p < 0.05) during the mornings (0800 to 1100 h) of days 2 to 4 and the evening of day 1 than days -4 to 0. Symptomatic ewes had lower activity levels in the morning and higher levels at night. After accounting for symptoms, activity levels during days 1 to 4 were lower (p < 0.05) than days -4 to 0 the morning after exposure. Results suggest real-time or near-real time accelerometers have potential to detect illness in ewes.

3.
Cladistics ; 37(4): 423-441, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34478190

RESUMO

Neotropical swarm-founding wasps are divided into 19 genera in the tribe Epiponini (Vespidae, Polistinae). They display extensive variation in several colony-level traits that make them an attractive model system for reconstructing the evolution of social phenotypes, including caste dimorphism and nest architecture. Epiponini has been upheld as a solid monophyletic group in most phylogenetic analyses carried out so far, supported by molecular, morphological and behavioural data. Recent molecular studies, however, propose different relationships among the genera of swarm-founding wasps. This study is based on the most comprehensive epiponine sampling so far and was analyzed by combining morphological, nesting and molecular data. The resulting phylogenetic hypothesis shows many of the traditional clades but still impacts the way certain behavioural characters, such as nest structure and castes, evolved, and thus requires some re-interpretations. Angiopolybia as sister to the remaining Epiponini implies that nest envelopes and a casteless system are plesiomorphic in the tribe. Molecular dating points to an early tribal diversification during the Eocene (c. 55-38 Ma), with the major differentiation of current genera concentrated in the Oligocene/Miocene boundary.


Assuntos
Ovário/fisiologia , Filogenia , Comportamento Social , Evolução Social , Vespas/anatomia & histologia , Vespas/fisiologia , Animais , Feminino , Geografia , Ovário/anatomia & histologia , Reprodução
4.
Rev Sci Instrum ; 92(12): 123903, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34972459

RESUMO

In this work, we describe the design and development of an in situ neutron reflectometry cell for high temperature investigations of structural changes occurring at the interface between inorganic salts, in their molten state up to 800 °C, and corrosion resistant alloys or other surfaces. In the cell, a molten salt is confined by an annular ring of single crystal sapphire constrained between the sample substrate and a sapphire plate using two gold O-rings, enclosing a liquid salt volume of 20 ml, along with a dynamic cell volume to accommodate expansion of the liquid with heating. As a test case for the cell, we report on an in situ neutron reflectometry measurement of the interface between a eutectic salt mixture of MgCl2-KCl (32:68 molar ratio) and a single crystal sapphire substrate at 450 °C, resulting in the formation of a 60 Å layer having a scattering length density of 1.72 × 10-6 Å-2. While the origin of this layer is uncertain, it is likely to have resulted from the salt reacting with an existing impurity layer on the sapphire substrate.

5.
Cladistics ; 36(4): 374-379, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-34618963

RESUMO

In the rush to understand the coronaviruses that threaten human health, authors of many prominent papers have not performed phylogenetic analyses to the standard of the field today. Errors include faulty placement of the root of the phylogeny, outdated methods of reconstruction, poor taxon sampling, inappropriate emphasis on selected functional elements, and inadequate consideration of ambiguity. As a result, certain conclusions regarding the origin of human infections are not supported soundly or are wrong.


Assuntos
COVID-19/prevenção & controle , Evolução Molecular , Genoma Viral/genética , Filogenia , SARS-CoV-2/genética , Animais , COVID-19/virologia , Quirópteros/virologia , Humanos , Pangolins/virologia , SARS-CoV-2/classificação , SARS-CoV-2/fisiologia , Viverridae/virologia
6.
Ibis, v. 163, n. 2, p. 380-389, nov. 2020
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3412

RESUMO

The Common Potoo Nyctibius griseus is abundant, charismatic and generally considered to be sedentary across its range. Using citizen science data from eBird and WikiAves, we demonstrate that the Common Potoo may be a partial migrant whose breeding populations depart southeastern Brazil, Uruguay and northern Argentina in May to August during the region’s austral winter. MaxEnt models revealed that spatio‐temporal shifts in Common Potoo distributions were driven by seasonal changes in temperature and precipitation. We examined potential seasonal detection biases by restricting our analysis to daytime observations and testing for seasonally dependent shifts in distribution for two nocturnal non‐migratory species. Our results provide the first evidence of migration for any member of the family Nyctibiidae. Our approach exposes the potential value that WikiAves data offer towards elucidating seasonal movements of South American birds.

7.
Ecol Appl ; 28(8): 2142-2152, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30198191

RESUMO

Environment and human land use both shape forest composition. Abiotic conditions sift tree species from a regional pool via functional traits that influence species' suitability to the local environment. In addition, human land use can modify species distributions and change functional diversity of forests. However, it is unclear how environment and land use simultaneously shape functional diversity of tree communities. Land-use legacies are especially prominent in temperate forest landscapes that have been extensively modified by humans in the last few centuries. Across a 900-ha temperate deciduous forest in the northeastern United States, comprising a mosaic of different-aged stands due to past human land use, we used four key functional traits-maximum height, rooting depth, wood density, and seed mass-to examine how multiple environmental and land-use variables influenced species distributions and functional diversity. We sampled ~40,000 trees >8 cm DBH within 485 plots totaling 137 ha. Species within plots were more functionally similar than expected by chance when we estimated functional diversity using all traits together (multi-trait), and to a lesser degree, with each trait separately. Multi-trait functional diversity was most strongly correlated with distance from the perennial stream, elevation, slope, and forest age. Environmental and land-use predictors varied in their correlation with functional diversities of the four individual traits. Landscape-wide change in abundances of individual species also correlated with both environment and land-use variables, but magnitudes of trait-environment interactions were generally stronger than trait interactions with land use. These findings can be applied for restoration and assisted regeneration of human-modified temperate forests by using traits to predict which tree species would establish well in relation to land-use history, topography, and soil conditions.


Assuntos
Biodiversidade , Meio Ambiente , Florestas , Árvores , Agricultura , Agricultura Florestal , Pennsylvania , Árvores/crescimento & desenvolvimento
8.
J Anim Ecol ; 87(1): 47-58, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28940239

RESUMO

Allee effects have important implications for many aspects of basic and applied ecology. The benefits of aggregation of conspecific individuals are central to Allee effects, which have led to the widely held assumption that social species are more prone to Allee effects. Robust evidence for this assumption, however, remains rare. Furthermore, previous research on Allee effects has failed to adequately address the consequences of the different levels of organisation within social species' populations. Here, we review available evidence of Allee effects and model the role of demographic and behavioural factors that may combine to dampen or strengthen Allee effects in social species. We use examples across various species with contrasting social structure, including carnivores, bats, primates and eusocial insects. Building on this, we provide a conceptual framework that allows for the integration of different Allee effects in social species. Social species are characterised by nested levels of organisation. The benefits of cooperation, measured by mean individual fitness, can be observed at both the population and group levels, giving rise to "population level" and "group level" Allee effects respectively. We also speculate on the possibility of a third level, reporting per capita benefits for different individuals within a group (e.g. castes in social insects). We show that group size heterogeneity and intergroup interactions affect the strength of population-level demographic Allee effects. Populations with higher group size heterogeneity and in which individual social groups cooperate demonstrate the weakest Allee effects and may thus provide an explanation for why extinctions due to Allee effects are rare in social species. More adequately accounting for Allee effects in social species will improve our understanding of the ecological and evolutionary implications of cooperation in social species.


Assuntos
Aptidão Genética , Insetos/fisiologia , Mamíferos/fisiologia , Animais , Evolução Biológica , Modelos Biológicos , Densidade Demográfica , Comportamento Social
10.
Anesthesiol Clin ; 34(2): 287-301, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27208711

RESUMO

Management of acute postoperative pain is important to decrease perioperative morbidity and improve patient satisfaction. Opioids are associated with potential adverse events that may lead to significant risk. Uncontrolled pain is a risk factor in the transformation of acute pain to chronic pain. Balancing these issues can be especially challenging in opioid-tolerant patients undergoing surgery, for whom rapidly escalating opioid doses in an effort to control pain can be associated with increased complications. In the perioperative surgical home model, anesthesiologists are positioned to coordinate a comprehensive perioperative analgesic plan that begins with the preoperative assessment and continues through discharge.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Analgésicos Opioides/efeitos adversos , Tolerância a Medicamentos , Humanos , Cuidados Intraoperatórios , Ketamina/uso terapêutico , Cuidados Pós-Operatórios , Cuidados Pré-Operatórios
11.
Ecology ; 96(3): 705-15, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26236867

RESUMO

Patterns of diversity and community composition in forests are controlled by a combination of environmental factors, historical events, and stochastic or neutral mechanisms. Each of these processes has been linked to forest community assembly, but their combined contributions to alpha and beta-diversity in forests has not been well explored. Here we use variance partitioning to analyze approximately 40,000 individual trees of 49 species, collected within 137 ha of sampling area spread across a 900-ha temperate deciduous forest reserve in Pennsylvania to ask (1) To what extent is site-to-site variation in species richness and community composition of a temperate forest explained by measured environmental gradients and by spatial descriptors (used here to estimate dispersal-assembly or unmeasured, spatially structured processes)? (2) How does the incorporation of land-use history information increase the importance attributed to deterministic community assembly? and (3) How do the distributions and abundances of individual species within the community correlate with these factors? Environmental variables (i.e., topography, soils, and distance to stream), spatial descriptors (i.e., spatial eigenvectors derived from Cartesian coordinates), and land-use history variables (i.e., land-use type and intensity, forest age, and distance to road), explained about half of the variation in both species richness and community composition. Spatial descriptors explained the most variation, followed by measured environmental variables and then by land- use history. Individual species revealed variable responses to each of these sets of predictor variables. Several species were associated with stream habitats, and others were strictly delimited across opposing north- and south-facing slopes. Several species were also associated with areas that experienced recent (i.e., <100 years) human land-use impacts. These results indicate that deterministic factors, including environmental and land-use history variables, are important drivers of community response. The large amount of "unexplained" variation seen here (about 50%) is commonly observed in other such studies attempting to explain distribution and abundance patterns of plant communities. Determining whether such large fractions of unaccounted for variation are caused by a lack of sufficient data, or are an indication of stochastic features of forest communities globally, will remain an important challenge for ecologists in the future.


Assuntos
Biodiversidade , Florestas , Árvores/fisiologia , Agricultura , Meio Ambiente , Agricultura Florestal , Mineração , Pennsylvania
12.
PLoS One ; 10(6): e0128161, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26046534

RESUMO

Anthropogenic disturbances often change ecological communities and provide opportunities for non-native species invasion. Understanding the impacts of disturbances on species invasion is therefore crucial for invasive species management. We used generalized linear mixed effects models to explore the influence of land-use history and distance to roads on the occurrence and abundance of two invasive plant species (Rosa multiflora and Berberis thunbergii) in a 900-ha deciduous forest in the eastern U.S.A., the Powdermill Nature Reserve. Although much of the reserve has been continuously forested since at least 1939, aerial photos revealed a variety of land-uses since then including agriculture, mining, logging, and development. By 2008, both R. multiflora and B. thunbergii were widespread throughout the reserve (occurring in 24% and 13% of 4417 10-m diameter regularly-placed vegetation plots, respectively) with occurrence and abundance of each varying significantly with land-use history. Rosa multiflora was more likely to occur in historically farmed, mined, logged or developed plots than in plots that remained forested, (log odds of 1.8 to 3.0); Berberis thunbergii was more likely to occur in plots with agricultural, mining, or logging history than in plots without disturbance (log odds of 1.4 to 2.1). Mining, logging, and agriculture increased the probability that R. multiflora had >10% cover while only past agriculture was related to cover of B. thunbergii. Proximity to roads was positively correlated with the occurrence of R. multiflora (a 0.26 increase in the log odds for every 1-m closer) but not B. thunbergii, and roads had no impact on the abundance of either species. Our results indicated that a wide variety of disturbances may aid the introduction of invasive species into new habitats, while high-impact disturbances such as agriculture and mining increase the likelihood of high abundance post-introduction.


Assuntos
Berberis/fisiologia , Rosa/fisiologia , Agricultura , Ecossistema , Espécies Introduzidas , Mineração , Estados Unidos
13.
Zootaxa ; 3682: 421-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25243297

RESUMO

Cely and Sarmiento (2011) took issue with the cladistic analysis of relationships among species of the genus Synoeca by Andena et al. (2009a), and presented a reanalysis. They claimed that intraspecific variation in the genus is meaningful, and proper consideration yields a conclusion different from that of Andena et al. Both their critique and reanalysis are vitiated by numerous errors, as is shown in the present paper.


Assuntos
Filogenia , Vespas/anatomia & histologia , Vespas/classificação , Animais , Feminino , Masculino , Comportamento de Nidação , Vespas/fisiologia
14.
Neotrop Entomol ; 39(4): 549-54, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20877990

RESUMO

Morphometric studies performed in several species of Neotropical social wasps from the tribe Epiponini showed that in some species there are marked differences between castes, while other species present highly distinct castes with differences only in ovarian development. This work analyzed females from six colonies of the social wasp Leipomeles dorsata (Fabricius) in which queens (egglayers) and workers showed differences in ovarian development and coloration. We propose that wasps with developed ovaries (egglayers) and coloration similar to those of workers are possibly intermediates that obtained the status of queens in the colony.


Assuntos
Comportamento Social , Vespas , Fatores Etários , Animais , Feminino , Vespas/anatomia & histologia
15.
Neotrop. entomol ; 39(4): 549-554, July-Aug. 2010. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-558840

RESUMO

Morphometric studies performed in several species of Neotropical social wasps from the tribe Epiponini showed that in some species there are marked differences between castes, while other species present highly distinct castes with differences only in ovarian development. This work analyzed females from six colonies of the social wasp Leipomeles dorsata (Fabricius) in which queens (egglayers) and workers showed differences in ovarian development and coloration. We propose that wasps with developed ovaries (egglayers) and coloration similar to those of workers are possibly intermediates that obtained the status of queens in the colony.


Assuntos
Animais , Feminino , Comportamento Social , Vespas , Fatores Etários , Vespas/anatomia & histologia
16.
Proc Natl Acad Sci U S A ; 106(13): 5229-34, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19289848

RESUMO

The evolutionary diversification of spiders is attributed to spectacular innovations in silk. Spiders are unique in synthesizing many different kinds of silk, and using silk for a variety of ecological functions throughout their lives, particularly to make prey-catching webs. Here, we construct a broad higher-level phylogeny of spiders combining molecular data with traditional morphological and behavioral characters. We use this phylogeny to test the hypothesis that the spider orb web evolved only once. We then examine spider diversification in relation to different web architectures and silk use. We find strong support for a single origin of orb webs, implying a major shift in the spinning of capture silk and repeated loss or transformation of orb webs. We show that abandonment of costly cribellate capture silk correlates with the 2 major diversification events in spiders (1). Replacement of cribellate silk by aqueous silk glue may explain the greater diversity of modern orb-weaving spiders (Araneoidea) compared with cribellate orb-weaving spiders (Deinopoidea) (2). Within the "RTA clade," which is the sister group to orb-weaving spiders and contains half of all spider diversity, >90% of species richness is associated with repeated loss of cribellate silk and abandonment of prey capture webs. Accompanying cribellum loss in both groups is a release from substrate-constrained webs, whether by aerially suspended webs, or by abandoning webs altogether. These behavioral shifts in silk and web production by spiders thus likely played a key role in the dramatic evolutionary success and ecological dominance of spiders as predators of insects.


Assuntos
Evolução Biológica , Seda/genética , Aranhas/genética , Animais , Biodiversidade , Filogenia , Comportamento Predatório
17.
Cladistics ; 24(4): 515-542, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34879633

RESUMO

Locust phase polyphenism is an extreme form of density-dependent phenotypic plasticity in which solitary and cryptic grasshoppers can transform into gregarious and conspicuous locusts in response to an increase in local population density. We investigated the evolution of this complex phenotypic plasticity in a phylogenetic framework using a morphological phylogeny of Cyrtacanthacridinae, which contains some of the most important locust species, and a comprehensive literature review on the biology and ecology of all known members of the subfamily. A phylogenetic analysis based on 71 morphological characters yielded a well-resolved tree and found that locust phase polyphenism evolved multiple times within the subfamily. The literature review demonstrated that many cyrtacanthacridine species, both locust and sedentary, are capable of expressing density-dependent color plasticity. When this color plasticity was divided into two smaller components, background coloration and development of black pigmentation, and when these plastic traits were optimized on to the phylogeny, we found that the physiological mechanisms underlying this plasticity were plesiomorphic for the subfamily. We also found that different locust species in Cyrtacanthacridinae express both similarities and differences in their locust phase polyphenism. Because locust phase polyphenism is a complex syndrome consisting of numerous plastic traits, we treat it as a composite character and dissected it into smaller components. The similarities among locust species could be attributed to shared ancestry and the differences could be attributed to the certain components of locust phase polyphenism evolving at different rates. © The Willi Hennig Society 2007.

18.
Rev. etol ; 8(1): 63-69, jun. 2006. ilus, graf
Artigo em Português | LILACS | ID: lil-447775

RESUMO

Muitos acreditam que com o seqüenciamento do DNA não será mais necessária qualquer outra informação, como a relativa ao comportamento, para inferir passos e origens evolutivas. Em nossa opinião, sempre precisaremos de caracteres mais complexos, como os caracteres comportamentais, para a realização de estudos evolutivos. Estudos evolutivos ou filogenias sem referência aos caracteres fenotípicos são necessariamente incompletos. Não há sentido em estudar-se o DNA sem referência ao fenótipo. Com o advento da genômica, o estudo do comportamento pode parecer estar em segundo plano. Entretanto, argumentos importantes em favor desse estudo podem ser levantados


Assuntos
Comportamento , Evolução Biológica , Genômica
19.
Rev. etol ; 8(1): 63-69, jun. 2006. ilus, graf
Artigo em Português | Index Psicologia - Periódicos | ID: psi-33093

RESUMO

Muitos acreditam que com o seqüenciamento do DNA não será mais necessária qualquer outra informação, como a relativa ao comportamento, para inferir passos e origens evolutivas. Em nossa opinião, sempre precisaremos de caracteres mais complexos, como os caracteres comportamentais, para a realização de estudos evolutivos. Estudos evolutivos ou filogenias sem referência aos caracteres fenotípicos são necessariamente incompletos. Não há sentido em estudar-se o DNA sem referência ao fenótipo. Com o advento da genômica, o estudo do comportamento pode parecer estar em segundo plano. Entretanto, argumentos importantes em favor desse estudo podem ser levantados (AU)


Assuntos
Comportamento , Evolução Biológica , Genômica
20.
Cladistics ; 22(4): 387-389, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34892865

RESUMO

A three-part series of workshops in phylogenetic methods was held at the Ohio State University in September and December 2005. The first two were sponsored by the OSU Mathematical Biosciences Institute (MBI), and focused on phylogeography and phylogenetic data, and phylogenetic analysis of large data sets respectively. These workshops highlighted theoretical and practical aspects of phylogeographic inferences using model-based approaches (e.g. likelihood and Bayesian MCMC), as well as current approaches to analyzing large datasets using both parsimony and model-based methods. The third workshop was sponsored by OSU systematics faculty, and was intended to provide practical training in current tools of phylogenetic analysis at the beginning and intermediate levels. The success of these workshops emphasizes the need for greater interaction between those involved in theoretical and empirical phylogenetic research. Further workshops, such as these, would serve to bring a practical understanding of these methods to as broad an audience as possible.

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