356 research outputs found

    Informetria: explorando bases de dados como instrumentos de análise

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    O artigo aborda os programas de pesquisa do Centro de Estudos Informétricos de Copenhague. Descrevendo a informetria como subcampo da bibliometria, discute uma nova abordagem para a área, qual seja, a combinação de teorias e metodologias avançadas de recuperação da informação com o estudo científico dos fluxos da informação. O Centro objetiva aplicar métodos bibliométricos não somente em estudos cienciométricos e em avaliações da pesquisa científica e tecnológica, mas também na análise de suas relações sociais, econômicas etc., ampliando as análises bibliométricas tradicionais para abranger as comunidades não acadêmicas nas quais a informação é produzida, comunicada e usada. A autora também convoca os profissionais de biblioteconomia e ciência da informação para enfrentarem o desafio dessa nova área de estudos quantitativos, aprendendo a explorar as bases de dados também como um instrumento para desenvolver atividades de análise, enfatizando as possibilidades que esses profissionais têm para elevar o nível de suas posições hierárquicas, assim como para explorar as técnicas informétricas no gerenciamento de políticas e de tomadas de decisão

    The impact of exhibit type on behaviour of caged and free-ranging tamarins

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    The lack of appropriate stimuli associated with captive environments has been documented to cause several behavioural and physiological issues in captive species, including loss of natural behaviours, psychopathologies and decreased reproductive success. Providing free-ranging, naturalistic exhibits that replicate elements of a species’ natural environment is advocated as a means of promoting and preserving the natural behavioural repertoire in captive species. Exhibition of natural behaviour is considered beneficial to conservation in terms of animal health and welfare, reintroduction success, education and research. This study assessed differences in behaviour of emperor and pied tamarins housed in free-ranging and caged exhibits at Durrell Wildlife Park to determine the impact of exhibit type. Free-ranging tamarins were expected to exhibit a repertoire of behaviours more similar to that of wild tamarins based on their access to a more naturalistic and complex environment. Data was collected on a variety of behaviours, including activity, substrate use and communication, using instantaneous and one-zero sampling at 30 s intervals. Findings indicated that both free-ranging and caged tamarins exhibited natural behaviours; however, there were significant differences in mean rates of behaviours between conditions. Free-ranging tamarins exhibited significantly higher rates of locomotion (emperors: P < 0.001; pieds: P < 0.001), long calls (pieds: P = 0.019) and alarm calls (emperors: P = 0.012), and displayed competent use of the environment in terms of natural substrate use (emperors: P < 0.001; pieds: P = 0.007) and interspecific interactions. Caged tamarins exhibited significantly higher rates of affiliative (emperors: P = 0.001; pieds: P = 0.026) and agonistic (emperors: P = 0.003) intraspecific interactions and time spent in contact (emperors: P = 0.048; pieds: P = 0.043), which was largely attributed to spatial restrictions imposed by caged exhibits. This study, consistent with existing literature, indicated that the free-ranging exhibit was conducive to the expression of a behavioural repertoire more similar to that of wild tamarins. This was probably a result of the increased behavioural opportunities available in the free-ranging exhibit, highlighting their importance in promoting wild-type behaviours. However, some mean rates of behaviour were still noticeably less than those documented in wild counterparts. Methods to further promote natural behaviours in both exhibits are recommended to facilitate ex situ and in situ conservation efforts

    Predictors of dominance rank and agonistic interactions in captive Livingstone’s fruit bats

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    Male dominance hierarchies have been studied in many animals but rarely in bats (Chiroptera). The dominance rank of social animals may dictate access to resources and mates; therefore, it has important implications for an individual’s fitness and is crucial for successful captive management. Between January and December 2018, at both Bristol Zoo Gardens (Bristol, UK) and Jersey Zoo (Jersey, British Isles), we observed 19 male Livingstone’s fruit bats Pteropus livingstonii using focal follows for 345 h overall, noting the outcome of all agonistic interactions. We recorded instigators of interactions, along with winners and losers, and analyzed these data using the R-package “EloRating” to create Elo-rating temporal plots of dominance ranks. We used generalized linear mixed models and multiple linear regression to analyze interaction data and test hypotheses regarding predictors of dominance rank, frequency of agonistic interaction, and choice of interaction partner. Age was positively correlated with dominance rank up to around year 9, when an asymptote was attained. Highly ranked bats instigated the most agonistic interactions, and largely directed these interactions at bats with much lower rankings than themselves. Hierarchies were extremely stable throughout the data collection period at both sites. We conclude that Livingstone’s fruit bats have a stable linear dominance hierarchy, with high-ranking, typically older males instigating the most interactions with lowest ranking males to secure dominance rank. This study adds to the limited discourse on Pteropus social behaviors, indicating that some bat species may have social systems similar in complexity to some nonhuman primates.<br/

    Roman Concepts of the Afterlife in the Late Republic and Early Principate

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    The topic has not been covered in detail since Cumont's book of 1922. This thesis covers the proportion of Roman paganism from 100BCE to 14CE. The sources of contemporary information are the writings of educated, and presumably wealthy, Romans, and such epitaphs and funerary inscriptions as have survived weather and (other destructive effects. There was no theologian. The nearest would be philosophers, but relevant writings of only two have survived. Three major philosophical systems existed, all derived from Greece. Epicureans held that there was no afterlife, Stoics that there was, and Academicians that there probably was but this could not be proved. Lucretius wrote a long poem to commend Epicureanism under which, since death was final, there could be no posthumous punishment or reward. Cicero covered all three systems in detail later writings, purporting to be an Academician, finally to Stoicism. The other writers who considered death were poets, but we do not know whether any of them believed what they wrote. It was essentially written as literature and should be judged as such. All except one seem to have believed that there was a life of some sort after death, and they either followed some part of Book 6 of the Aeneid of Virgil or used the same sources. There are many epitaphs and inscriptions, but most are purely biographical. Only a small proportion give any hint about an afterlife. This thesis has extracted some which directly or implicitly support or deny its existence. It is not possible to make a meaningful statistical study since we do not know what proportion of original epitaphs have survived. The study has shown that there was no one concept which expresses the Roman view of the afterlife. Homer's gloomy picture would have been well known since his works were the basis of Roman education. How far the philosophers' ideas penetrated the thought of the majority of Romans impossible to determine, but the prospect of evil punished and virtue rewarded must have been attractive

    Synthesis and analysis of the anticancer activity of platinum(ii) complexes incorporating dipyridoquinoxaline variants

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    Eight platinum(ii) complexes with anticancer potential have been synthesised and characterised. These complexes are of the type [Pt(I)(A)], where I is either dipyrido[3,2-f:2′,3′-h]quinoxaline (dpq) or 2,3-dimethyl-dpq (23Medpq) and A is one of the R,R or S,S isomers of either 1,2-diaminocyclohexane (SS-dach or RR-dach) or 1,2-diaminocyclopentane (SS-dacp or RR-dacp). The CT-DNA binding of these complexes and a series of other complexes were assessed using fluorescent intercalator displacement assays, resulting in unexpected trends in DNA binding affinity. The cytotoxicity of the eight synthesised compounds was determined in the L1210 cell line; the most cytotoxic of these were [Pt(dpq)(SS-dach)]Cl and [Pt(dpq)(RR-dach)]Cl, with IC values of 0.19 and 0.80 μM, respectively. The X-ray crystal structure of the complex [Pt(dpq)(SS-dach)](ClO)·1.75HO is also reported. This journal i

    Infrared absorbance spectroscopy of aqueous proteins : comparison of transmission and ATR data collection and analysis for secondary structure fitting

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    Attenuated total reflectance (ATR) infrared absorbance spectroscopy of proteins in aqueous solution is much easier to perform than transmission spectroscopy, where short path‐length cells need to be assembled reproducibly. However, the shape of the resulting ATR infrared spectrum varies with the refractive index of the sample and the instrument configuration. Refractive index in turn depends on the absorbance of the sample. In this work, it is shown that a room temperature triglycine sulfate detector and a ZnSe ATR unit can be used to collect reproducible spectra of proteins. A simple method for transforming the protein ATR spectrum into the shape of the transmission spectrum is also given, which proceeds by approximating a Kramers‐Krönig–determined refractive index of water as a sum of four linear components across the amide I and II regions. The light intensity at the crystal surface (with 45° incidence) and its rate of decay away from the surface is determined as a function of the wave number–dependent refractive index as well as the decay of the evanescent wave from the surface. The result is a single correction factor at each wave number. The spectra were normalized to a maximum of 1 between 1600 cm−1 and 1700 cm−1 and a self‐organizing map secondary structure fitting algorithm, SOMSpec, applied using the BioTools reference set. The resulting secondary structure estimates are encouraging for the future of ATR spectroscopy for biopharmaceutical characterization and quality control applications

    A Manual of Poultry Diseases.

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