2,786 research outputs found

    Asymmetric synthesis of tri- and tetrasubstituted trifluoromethyl dihydropyranones from alpha-aroyloxyaldehydes via NHC redox catalysis

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    We thank the Royal Society for a University Research Fellowship (A.D.S.), and the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) ERC Grant Agreement No. 279850 (A.T.D.).The asymmetric synthesis of tri- and tetrasubstituted trifluoromethyl dihydropyranones via an NHC-catalyzed redox process, introducing methyl, benzyl, and aryl substituents to the C(5) position, is presented. Their substrate-controlled derivatization into δ-lactones and cyclic hemiacetals containing stereogenic trifluoromethyl groups is also described.PostprintPeer reviewe

    Adaptation without natural selection

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    Document is itself an extended abstract

    Munchausen Syndrome by Proxy: Identification and Intervention

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    Munchausen Syndrome by Proxy (MSBP), also known as “factitious disorder by proxy,” is a mental illness in which a person lies about the physical or mental well-being of a person he/she is responsible for (The Cleveland Clinic, 2008). Most often the dynamic transpires between a mother and her child. The motivation behind MSBP is that the adult seeks the attention typically given to those who are sick, and attempts to get the attention by causing or lying about illness in his/her child. MSBP is a type of child abuse and can result in long-term physical and psychological effects or even death (Roesler & Jenny, 2009). ... The mental illness of MSBP is a label given to adults, and MSBP as well as its cousin Munchausen Syndrome (in which individuals feign disease, illness, or psychological trauma in themselves to draw sympathy) are both adult-onset disorders. However, children are affected severely by this disorder, as evidenced by the above case study. Children who are abused by MSBP often are chronically absent from school, are subjected to numerous, painful, unnecessary medical procedures, are physically and mentally abused by parents, and suffer long-term psychological damage if they survive the abuse (Sheridan, 2003)

    Galactic Archaeology with TESS: Prospects for Testing the Star Formation History in the Solar Neighbourhood

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    A period of quenching between the formation of the thick and thin disks of the Milky Way has been recently proposed to explain the observed age-[{\alpha}/Fe] distribution of stars in the solar neighbourhood. However, robust constraints on stellar ages are currently available for only a limited number of stars. The all-sky survey TESS (Transiting Exoplanet Survey Satellite) will observe the brightest stars in the sky and thus can be used to investigate the age distributions of stars in these components of the Galaxy via asteroseismology, where previously this has been difficult using other techniques. The aim of this preliminary study was to determine whether TESS will be able to provide evidence for quenching periods during the star formation history of the Milky Way. Using a population synthesis code, we produced populations based on various stellar formation history models and limited the analysis to red-giant-branch stars. We investigated the mass-Galactic-disk-height distributions, where stellar mass was used as an age proxy, to test for whether periods of quenching can be observed by TESS. We found that even with the addition of 15% noise to the inferred masses, it will be possible for TESS to find evidence for/against quenching periods suggested in the literature (e.g. between 7 and 9 Gyr ago), therefore providing stringent constraints on the formation and evolution of the Milky Way.Comment: 4 pages, 3 figures, proceedings of "Seismology of the Sun and the Distant Stars 2016", Mario J. P. F. G. Monteiro, Margarida S. Cunha, Joao Miguel T. Ferreira editor

    Enantioselective NHC-catalyzed redox [2+2] cycloadditions with perfluoroketones; a route to fluorinated oxetanes

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    The authors thank the Royal Society for a University Research Fellowship (A.D.S.), and the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) ERC grant agreement no. 279850 (A.T.D.).The N-heterocyclic carbene (NHC) catalyzed redox formal [2+2] cycloaddition between α-aroyloxyaldehydes and perfluoroketones, followed by ring-opening in situ delivers a variety of perfluorinated β-hydroxycarbonyl compounds in good yield, and excellent diastereo- and enantioselectivity. Through a reductive work-up and subsequent cyclization, this protocol offers access to highly substituted fluorinated oxetanes in two steps and in high ee.PostprintPeer reviewe

    Eating disorder symptoms and control-seeking behavior

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    OBJECTIVE: Eating disorders (EDs) are a heterogenous group of disorders characterized by disturbed eating patterns. Links have been made between ED symptoms and control-seeking behaviors, which may cause relief from distress. However, whether direct behavioral measures of control-seeking behavior correlate with ED symptoms has not been directly tested. Additionally, existing paradigms may conflate control-seeking behavior with uncertainty-reducing behavior. METHOD: A general population sample of 183 participants completed part in an online behavioral task, in which participants rolled a die in order to obtain/avoid a set of numbers. Prior to each roll, participants could choose to change arbitrary features of the task (such as the color of their die) or view additional information (such as the current trial number). Selecting these Control Options could cost participants points or not (Cost/No-Cost conditions). Each participant completed all four conditions, each with 15 trials, followed by a series of questionnaires, including the Eating Attitudes Test-26 (EAT-26), the Intolerance of Uncertainty Scale, and the Obsessive-Compulsive Inventory-Revised (OCI-R). RESULTS: A Spearman's rank test indicated no significant correlation between total EAT-26 score and total number of Control Options selected, with only elevated scores on a measure of obsessions and compulsivity (OCI-R) correlating with the total number of Control Options selected (rs  = .155, p = .036). DISCUSSION: In our novel paradigm, we find no relationship between EAT-26 score and control-seeking. However, we do find some evidence that this behavior may be present in other disorders that often coincide with ED diagnosis, which may indicate that transdiagnostic factors such as compulsivity are important to control-seeking

    Statistical Physics Approaches to Unique Games

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    We show how two techniques from statistical physics can be adapted to solve a variant of the notorious Unique Games problem, potentially opening new avenues towards the Unique Games Conjecture. The variant, which we call Count Unique Games, is a promise problem in which the "yes" case guarantees a certain number of highly satisfiable assignments to the Unique Games instance. In the standard Unique Games problem, the "yes" case only guarantees at least one such assignment. We exhibit efficient algorithms for Count Unique Games based on approximating a suitable partition function for the Unique Games instance via (i) a zero-free region and polynomial interpolation, and (ii) the cluster expansion. We also show that a modest improvement to the parameters for which we give results would be strong negative evidence for the truth of the Unique Games Conjecture

    Sarcasm and emoticons: comprehension and emotional impact

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    Most theorists agree that sarcasm serves some communicative function that would not be achieved by speaking directly, such as eliciting a particular emotional response in the recipient. One debate concerns whether this kind of language serves to enhance or mute the positive or negative nature of a message. The role of textual devices commonly used to accompany written sarcastic remarks is also unclear. The current research uses a rating task to investigate the influence of textual devices (emoticons and punctuation marks) on the comprehension of, and emotional responses to, sarcastic versus literal criticism and praise, for both unambiguous (Experiment 1) and ambiguous (Experiment 2) materials. Results showed that sarcastic criticism was rated as less negative than literal criticism, and sarcastic praise was rated as less positive than literal praise, suggesting that sarcasm serves to mute the positive or negative nature of the message. In terms of textual devices, results showed that emoticons had a larger influence on both comprehension and emotional impact than punctuation marks
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