214 research outputs found

    Kinetic Resolution in Asymmetric Epoxidation using Iminium Salt Catalysis

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    The first reported examples of kinetic resolution in epoxidation reactions using iminium salt catalysis are described, providing up to 99% ee in the epoxidation of racemic cis-chromenes

    OBEDIÊNCIA INCIVIL (UNCIVIL OBEDIENCE)

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    [1] Tradução do inglês por Bruno Meneses Lorenzetto e Jorge Rafael Matos.Resumo:Acadêmicos e ativistas há muito estão interessados na prática consciente da transgressão da lei como meio de dissenso. O desobediente civil viola a lei em um apelo para realçar sua ilegitimidade e motivar sua reforma. Uma forma menos proclamada de ação social, contudo, envolve aproximadamente a aproximação oposta. Como uma ampla gama de exemplos atesta, dissidentes podem também buscar a perturbação de regimes legais pela aderência hiperbólica, literal, ou imprevista de suas regras formais.Este artigo questiona como fazer sentido destes protestos paradoxais, envolvendo não a transgressão explícita da lei mas, ao invés, formas extremadas de cumprimento da lei. Nós buscamos identificar, elucidar e chamar atenção para o fenômeno da obediência incivil. Depois de definir a obediência incivil e descrever suas variedades e mecanismos básicos, nós exploramos instrumentos que emergiram para limitar o seu uso. Nós explicamos que o direito privado desenvolveu defesas mais robustas contra a obediência incivil do que o direito público, especialmente nas jurisdições de civil law. Nós argumentamos que os desafios que a obediência incivil estabeleceu para os valores do direito público são tão substantivos quanto os estabelecidos pela desobediência civil. E nós sugerimos que a obediência incivil pode ser uma tática particularmente atrativa para indivíduos ideologicamente conservadores no Partido Republicano. Por estas razões e outras, o artigo busca mostrar que a obediência incivil merece muito mais do tipo de atenção crítica do que a que foi dirigida para a desobediência civil

    A theory on reports of constructive (real) and illusory posttraumatic growth

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    It has been suggested that self-reported posttraumatic growth could sometimes be considered as a way for people to protect themselves from the distress of trauma. In this case, reports of posttraumatic growth could be illusory. We suggest a theory on self-reported constructive (real) posttraumatic growth and illusory posttraumatic growth by using Rogers’s (1959) theory and the work by Vaillant (1995). Through this theoretical framework we attempt to explain when reports of posttraumatic growth are likely to be constructive and real and when such reports are likely to represent aspects of illusions. We will also consider the implications for research practice

    “Janus” Calixarenes: Double-Sided Molecular Linkers for Facile, Multianchor Point, Multifunctional, Surface Modification

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    We herein report the synthesis of novel “Janus” calix[4]arenes bearing four “molecular tethering” functional groups on either the upper or lower rims of the calixarene. These enable facile multipoint covalent attachment to electrode surfaces with monolayer coverage. The other rim of the calixarenes bear either four azide or four ethynyl functional groups, which are easily modified by the copper(I)-catalyzed azide–alkyne cycloaddition reaction (CuAAC), either pre- or postsurface modification, enabling these conical, nanocavity reactor sites to be decorated with a wide range of substrates to impart desired chemical properties. Redox active species decorating the peripheral rim are shown to be electrically connected by the calixarene to the electrode surface in either “up” or “down” orientations of the calixarene

    Ground Testing a Nuclear Thermal Rocket: Design of a Sub-scale Demonstration Experiment

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    In 2008, the NASA Mars Architecture Team found that the Nuclear Thermal Rocket (NTR) was the preferred propulsion system out of all the combinations of chemical propulsion, solar electric, nuclear electric, aerobrake, and NTR studied. Recently, the National Research Council committee reviewing the NASA Technology Roadmaps recommended the NTR as one of the top 16 technologies that should be pursued by NASA. One of the main issues with developing a NTR for future missions is the ability to economically test the full system on the ground. In the late 1990s, the Sub-surface Active Filtering of Exhaust (SAFE) concept was first proposed by Howe as a method to test NTRs at full power and full duration. The concept relied on firing the NTR into one of the test holes at the Nevada Test Site which had been constructed to test nuclear weapons. In 2011, the cost of testing a NTR and the cost of performing a proof of concept experiment were evaluated

    Exome Sequencing as a Diagnostic Tool for Pediatric-Onset Ataxia

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    Ataxia demonstrates substantial phenotypic and genetic heterogeneity. We set out to determine the diagnostic yield of exome sequencing in pediatric patients with ataxia without a molecular diagnosis after standard-of-care assessment in Canada. FORGE (Finding Of Rare disease GEnes) Canada is a nation-wide project focused on identifying novel disease genes for rare pediatric diseases using whole-exome sequencing. We retrospectively selected all FORGE Canada projects that included cerebellar ataxia as a feature. We identified 28 such families and a molecular diagnosis was made in 13; a success rate of 46%. In 11 families, we identified mutations in genes associated with known neurological syndromes and in two we identified novel disease genes. Exome analysis of sib pairs and/or patients born to consanguineous parents was more likely to be successful (9/13) than simplex cases (4/15). Our data suggest that exome sequencing is an effective first line test for pediatric patients with ataxia where a specific single gene is not immediately suspected to be causative. © 2013 The Authors. *Human Mutation published by Wiley Periodicals, Inc

    BAFopathies\u27 DNA methylation epi-signatures demonstrate diagnostic utility and functional continuum of Coffin-Siris and Nicolaides-Baraitser syndromes.

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    Coffin-Siris and Nicolaides-Baraitser syndromes (CSS and NCBRS) are Mendelian disorders caused by mutations in subunits of the BAF chromatin remodeling complex. We report overlapping peripheral blood DNA methylation epi-signatures in individuals with various subtypes of CSS (ARID1B, SMARCB1, and SMARCA4) and NCBRS (SMARCA2). We demonstrate that the degree of similarity in the epi-signatures of some CSS subtypes and NCBRS can be greater than that within CSS, indicating a link in the functional basis of the two syndromes. We show that chromosome 6q25 microdeletion syndrome, harboring ARID1B deletions, exhibits a similar CSS/NCBRS methylation profile. Specificity of this epi-signature was confirmed across a wide range of neurodevelopmental conditions including other chromatin remodeling and epigenetic machinery disorders. We demonstrate that a machine-learning model trained on this DNA methylation profile can resolve ambiguous clinical cases, reclassify those with variants of unknown significance, and identify previously undiagnosed subjects through targeted population screening
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