2,512 research outputs found

    Sheeple? The need for more research on sheep cognition

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    Marino & Merskin (2019) provide a comprehensive review of the cognitive abilities of sheep. If research with other animals is any guide, there may be justification for the view that the abilities of sheep have been underestimated, and their review will likely stimulate more research into sheep cognition

    Neural Correlates of Executive Control in the Avian Brain

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    Executive control, the ability to plan one's behaviour to achieve a goal, is a hallmark of frontal lobe function in humans and other primates. In the current study we report neural correlates of executive control in the avian nidopallium caudolaterale, a region analogous to the mammalian prefrontal cortex. Homing pigeons (Columba livia) performed a working memory task in which cues instructed them whether stimuli should be remembered or forgotten. When instructed to remember, many neurons showed sustained activation throughout the memory period. When instructed to forget, the sustained activation was abolished. Consistent with the neural data, the behavioural data showed that memory performance was high after instructions to remember, and dropped to chance after instructions to forget. Our findings indicate that neurons in the avian nidopallium caudolaterale participate in one of the core forms of executive control, the control of what should be remembered and what should be forgotten. This form of executive control is fundamental not only to working memory, but also to all cognition

    Introspection and anecdotes won’t prove what animals are thinking and feeling

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    We review Part Three, “Whines and Pet Peeves,” of Safina’s book Beyond Words: What Animals Think and Feel. Part Three is concerned mainly with the evidence for Theory of Mind in nonhuman animals. Like Safina, we believe that animals have a Theory of Mind, and like Safina, we question the utility of such concepts. There are many studies that Safina could have used to support his argument, and although some are mentioned, he prefers to make his point mainly by relying on anecdotes and introspection. The end result, we believe, is to devalue the scientific process

    What are the consequences of ignoring attributes in choice experiments? An application to ecosystem service values

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    This paper investigates the sensitivity of choice experiment values for ecosystem services to “attribute non-attendance”. We consider three cases of attendance, namely that people may always, sometimes or never pay attention to a given attribute in making their choices. This allows a series of models to be estimated which address the following questions: To what extent do respondents attend to attributes in choice experiments? What is the impact of alternative strategies for dealing with attribute non-attendance? Can respondents self-report non-attendance? Do respondents partially attend to attributes, and what are the implications of this for willingness to pay estimates? Our results show that allowing for the instance of “sometimes attending” to attributes in making choices offers advantages over methods employed thus far in the literature

    Study of C- and O-glycosylflavones in sugarcane extracts using liquid chromatography: exact mass measurement mass spectrometry

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    The flavonoids present in sugarcane (Saccharum officinarum) extracts were analyzed by liquid chromatography - mass spectrometry (LC-MS), and a study of the fragmentation patterns of selected flavonoids was conducted using orthogonal acceleration time-of-flight electrospray ionization mass spectrometry (ESI-oa-ToF MS). Seven C- and O-glycosylflavones were identified in the extracts, namely, schaftoside, isoschaftoside, luteolin-8-C-(rhamnosylglucoside), vitexin, orientin, tricin-7-O-neohesperidoside and tricin-7-O-glucoside. Of these, five were identified in the absence of direct comparison with their respective standards. The described method also permitted the differentiation of the 6-C and 8-C isomeric flavones, schaftoside and isoschaftoside. The combination of fragmentation data and exact mass measurement showed to be complimentary to the HPLC-UV-MS techniques previously utilized for isomers discrimination in sugarcane studies.Os flavonĂłides presentes nos extratos de cana-de-açĂșcar (Saccharum officinarum) foram analisados por cromatografia lĂ­quida acoplada Ă  espectrometria de massas (LC-MS), e o estudo da rota de fragmentação dos flavonĂłides selecionados foi realizado utilizando a espectrometria de massas com aceleração ortogonal por tempo de vĂŽo e ionização eletrospray (ESI-oa-ToF MS). Sete flavonas C- e O-glicosiladas foram identificadas nos extratos: schaftosĂ­deo, isoschaftosĂ­deo, luteolina-8-C-(ramnosilglicosĂ­deo), vitexina, orientina, tricina-7-O-neohesperidosĂ­deo e tricina-7-O-glicosĂ­deo. Destas, cinco foram identificadas sem comparação direta com seus respectivos padrĂ”es. O mĂ©todo descrito tambĂ©m permitiu a diferenciação das 6-C e 8-C flavonas isomĂ©ricas, schaftosĂ­deo e isoschaftosĂ­deo. A combinação dos dados de fragmentação e a medida de massa exata mostraram ser complementares Ă s tĂ©cnicas de HPLC-UV-MS previamente utilizadas para discriminação de isĂŽmeros nos estudos da cana-de-açĂșcar.FAPESPCNP

    Control of the Continuity Equation with a Non Local Flow

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    This paper focuses on the optimal control of weak (i.e. in general non smooth) solutions to the continuity equation with non local flow. Our driving examples are a supply chain model and an equation for the description of pedestrian flows. To this aim, we prove the well posedness of a class of equations comprising these models. In particular, we prove the differentiability of solutions with respect to the initial datum and characterize its derivative. A necessary condition for the optimality of suitable integral functionals then follows
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