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1.
ACS Omega ; 6(40): 25950-25963, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34660957

RESUMO

The fouling of AISI 316L stainless steel during themanufacture of polymeric methylene diphenyl diisocyanate (pMDI) has been investigated. Studies have been carried out using a laboratory-based rig that simulates the process chemistry of the production plant. A variety of solution concentrations and treatment times have been employed to represent different stages in the production process. Following exposure, steel coupons have been removed and studied by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The thickness of the fouling layer, determined by XPS, is found to vary inversely with exposure time and solution concentration. This is a result of the solubility of the different pMDI derivatives that have been formed at different stages, and a reaction scheme is developed to explain these inverse relationships. ToF-SIMS indicates the formation of metal chlorides as a result of the initial treatment of the steel in the reaction vessel with hydrogen chloride. Fragment ions characteristic of reacted and unreacted pMDI (at m/z = 106 and 132 au, respectively) were used as an indicator of the degree of reacted isocyanate groups within the fouling layer and show a decrease with increasing exposure time, as a result of the formation of intermediates such as amines, ureas, carbodiimides, and uretonimines. The ToF-SIMS data was also processed by principal component analysis (PCA). This generally reinforced the conclusions reached by XPS and ToF-SIMS but, in addition, gave confidence in the repeatability of the analyses with the repeat data (of four analyses) clustering very tightly in the PCA score plots.

2.
Elife ; 102021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34677128

RESUMO

Eurasian jays fail to take into account the point of view and desire of other jays when hiding food they can eat later.


Assuntos
Passeriformes , Aves Canoras , Animais , Comportamento Alimentar , Alimentos
4.
Front Psychol ; 8: 2100, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29238321

RESUMO

Inhibitory control refers to the ability to stop impulses in favor of more appropriate behavior, and it constitutes one of the underlying cognitive functions associated with cognitive flexibility. Much attention has been given to cross-species comparisons of inhibitory control; however, less is known about how and when these abilities develop. Mapping the ontogeny of inhibitory control in different species may therefore reveal foundational elements behind cognitive processes and their evolution. In this study, we tested the development of motor self-regulation in raven chicks (Corvus corax), using two detour tasks that required inhibition of motor impulses to directly reach for a visible reward behind a barrier. One task included a mesh barrier, which partly occluded the reward, and the other task used a completely transparent barrier, the cylinder task. The results suggest that the more visible a reward is, the more difficult it is to inhibit motor impulses toward it, and further, that this inhibitory challenge gradually decreases during development. The mesh barrier is reliably detoured before the animals pass the task with the wholly transparent cylinder. As the majority of the birds begun testing as nestlings, and as we provided them with experiences they normally would not receive in a nest, it is likely that they showed the earliest possible onset of these skills. A control subject, tested at a later age, showed that the mesh detours required no particular training, but that tasks including complete transparency likely require more specific experiences. Adult ravens without explicit training are highly proficient in inhibitory detour tasks, and, together with chimpanzees, they are the best performers of all tested species in the cylinder task. Our results suggest that their skills develop early in life, around their third month. Their developmental pattern of inhibitory skills for detours resembles that of children and rhesus macaques, albeit the pace of development is markedly faster in ravens. Investigating the development of cognition is crucial to understanding its foundations within and across species.

5.
Behav Brain Sci ; 40: e207, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29342661

RESUMO

The qualitative division between domain-general and domain-specific cognition is unsubstantiated. The distinction is instead better viewed as opposites on a gradual scale, which has more explanatory power and fits current empirical evidence better. We also argue that causal cognition may be more general than social learning, which it often involves.


Assuntos
Cognição , Inteligência
6.
Anim Cogn ; 19(6): 1249-1252, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27437926

RESUMO

New Caledonian crows (Corvus moneduloides) rely heavily on a range of tools to extract prey. They manufacture novel tools, save tools for later use, and have morphological features that facilitate tool use. We report six observations, in two individuals, of a novel tool-use mode not previously reported in non-human animals. Insert-and-transport tool use involves inserting a stick into an object and then moving away, thereby transporting both object and tool. All transported objects were non-food objects. One subject used a stick to transport an object that was too large to be handled by beak, which suggests the tool facilitated object control. The function in the other cases is unclear but seems to be an expression of play or exploration. Further studies should investigate whether it is adaptive in the wild and to what extent crows can flexibly apply the behaviour in experimental settings when purposive transportation of objects is advantageous.


Assuntos
Corvos , Comportamento de Utilização de Ferramentas , Animais
7.
Surgery ; 160(5): 1344-1357, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27316825

RESUMO

BACKGROUND: There is an increasing interest in patient-reported outcome measurement to evaluate hernia operations. Several hernia-specific quality of life (QoL) scales have been proposed, but none are constructed for preoperative assessment. METHODS: The European Registry for Abdominal Wall Hernias (EuraHS) proposed the short, 9-question EuraHS-QoL instrument for assessment pre- and postoperatively. The EuraHS-QoL was evaluated in a prospective, multicenter validation study alongside the Visual Analogue Scale, Verbal Rating Scale, and Carolina Comfort Scale (https://clinicaltrials.gov; NCT01936584). RESULTS: We included 101 patients undergoing unilateral laparoscopic inguinal hernia repair with ProGrip laparoscopic, self-fixating mesh. Clinical follow-up at 12 months was 87% complete. The EuraHS-QoL score shows good internal consistency (Cronbach's α ≥ .90), good test-retest reliability (Spearman correlation coefficient r ≥ 0.72), and high correlation for pain with the Visual Analogue Scale, the Verbal Rating Scale, the Carolina Comfort Scale pain scale (r between 0.64 and 0.86), and for restriction of activity with the Carolina Comfort Scale movement scale (r between 0.65 and 0.79). Our results show significant improvement in quality of life at 3 weeks compared with preoperative and further significant improvement at 12 months (P < .05). No late complications or recurrences were recorded. An operation was performed in day surgery (>75%) or with a <24-hour admission (>95%) in the majority of the patients. CONCLUSION: The EuraHS-QoL instrument is a short and valid patient-reported outcome measurement following groin hernia repair. Laparoscopic inguinal hernia repair with ProGrip laparoscopic, self-fixating mesh results in a favorable outcome and significant improvement of quality of life compared with the preoperative assessment.


Assuntos
Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Laparoscopia/métodos , Qualidade de Vida , Sistema de Registros , Telas Cirúrgicas/estatística & dados numéricos , Adulto , Europa (Continente) , Feminino , Seguimentos , Hérnia Inguinal/diagnóstico , Herniorrafia/psicologia , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/fisiopatologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Recidiva , Reprodutibilidade dos Testes , Medição de Risco , Autorrelato , Resultado do Tratamento
8.
J Comp Psychol ; 129(2): 89-120, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25984937

RESUMO

String pulling is one of the most widely used paradigms in comparative psychology. First documented 2 millennia ago, it has been a well-established scientific paradigm for a century. More than 160 bird and mammal species have been tested in over 200 studies with countless methodological variations. The paradigm can be used to address a wide variety of issues on animal cognition; for example, what animals understand about contact and connection as well as whether they rely on perceptual feedback, grasp the functionality of strings, generalize across conditions, apply their knowledge flexibly, and possess insight. Mammals are typically tested on a horizontal configuration, birds on a vertical one, making the studies difficult to compare; in particular, pulling a string vertically requires better coordination and attention. A species' performance on the paradigm is often influenced by its ecology, especially concerning whether limbs are used for foraging. Many other factors can be of importance and should be considered. The string-pulling paradigm is easy to administer, vary, and apply to investigate a wide array of cognitive abilities. Although it can be and has been used to compare species, divergent methods and unclear reporting have limited its comparative utility. With increasing research standards, the paradigm is expected to become an even more fundamental tool in comparative psychology.


Assuntos
Cognição , Psicologia Comparada/métodos , Animais , Atenção , Biorretroalimentação Psicológica , Aves , Compreensão , Mamíferos/psicologia , Desempenho Psicomotor , Comportamento de Utilização de Ferramentas
10.
Behav Processes ; 102: 25-32, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24333834

RESUMO

Food caching is a paramount model for studying relations between cognition, brain organisation and ecology in corvids. In contrast, behaviour towards inedible objects is poorly examined and understood. We review the literature on object caching in corvids and other birds, and describe an exploratory study on object caching in ravens, New Caledonian crows and jackdaws. The captive adult birds were presented with an identical set of novel objects adjacent to food. All three species cached objects, which shows the behaviour not to be restricted to juveniles, food cachers, tool-users or individuals deprived of cacheable food. The pattern of object interaction and caching did not mirror the incidence of food caching: the intensely food caching ravens indeed showed highest object caching incidence, but the rarely food caching jackdaws cached objects to similar extent as the moderate food caching New Caledonian crows. Ravens and jackdaws preferred objects with greater sphericity, but New Caledonian crows preferred stick-like objects (similar to tools). We suggest that the observed object caching might have been expressions of exploration or play, and deserves being studied in its own right because of its potential significance for tool-related behaviour and learning, rather than as an over-spill from food-caching research. This article is part of a Special Issue entitled: CO3 2013.


Assuntos
Comportamento Animal/fisiologia , Corvos/fisiologia , Comportamento Exploratório/fisiologia , Comportamento Alimentar/fisiologia , Animais , Feminino , Alimentos , Masculino
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