8,439 research outputs found
Data for Superlattice by charged block copolymer self-assembly
No full textThe file includes the X-ray scattering data, determination of reactivity ratios, polymerization kinetics, NMR, SEC, Bjerrum length, and probability distribution profile data for all reported figures. The readme file further describes the individual data.These files contain data along with the associated output from instrumentation supporting all results reported in "Superlattice by charged block copolymer self-assembly" by Shim et. al. We report the discovery of an intriguing superlattice morphology from compositionally symmetric charged block copolymers, poly[(oligo(ethylene glycol) methyl ether methacrylate–co–oligo(ethylene glycol) propyl sodium sulfonate methacrylate)]–b–polystyrene (POEGMA–PS). These materials are conveniently prepared by sequential reversible addition–fragmentation chain transfer (RAFT) polymerization, followed by introduction of charged groups, in a manner that allows for systematic variation of the molecular structure in general, and the charge content in particular. POEGMA–PS self-assembles into a superlattice lamellar morphology, a previously unknown class of diblock nanostructures, but strikingly similar to oxygen-deficient perovskite derivatives, when the fraction of charged groups in the POEGMA block is about 5–25%. The charge fraction in the POEGMA block, and the tethering of the ionic groups, both play critical roles in driving the formation of the superlattice. This study highlights the accessibility of novel morphologies by introducing charges in a controlled manner.The Office of Basic Energy Science (BES) of the U.S. Department of Energy (DoE), under Contract DE-FOA-0001664.Shim, Jimin; Bates, Frank S; Lodge, Timothy P. (2019). Data for Superlattice by charged block copolymer self-assembly. Retrieved from the University Digital Conservancy, https://doi.org/10.13020/qsa6-qg08
Congenital heart block associated with Sjögren syndrome: case report
No full textBackground: Congenital heart block is a rare complication of pregnancy associated with Sjögren Syndrome that may result in the death of the foetus or infant, or the need for pacing in the newborn or at a later stage.Case report: The case is presented of a 64-year-old patient with primary Sjögren Syndrome and a history of having given birth to two sons with congenital heart block, both of whom required pacing several years later.Conclusion: The literature relating to this association is discussed including the suggested mechanism, long-term outcome of mothers of children with congenital heart block and preventive treatment strategies
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Supporting data for Core−Shell Gyroid in ABC Bottlebrush Block Terpolymers
No full textThe data folder contains all small-angle X-ray scattering (SAXS) data, as well as proton nuclear magnetic resonance (1H NMR), size exclusion chromatography (SEC), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM) data. The nomenclature is consistent with that used in the manuscript. See the readme.txt file for further details.These files contain primary data supporting all results reported in Cui et al. "Core−shell gyroid in ABC bottlebrush block terpolymers." A series of bottlebrush block polymers containing 24 PEP-PS diblock copolymers and 109 PEP-PS-PEO triblock terpolymers were synthesized by ring-opening metathesis polymerization (ROMP) of norbornene-functionalized poly(ethylene-alt-propylene) (PEP), poly(styrene) (PS), and poly(ethylene oxide) (PEO) macromonomers. The molecular weights of the three macromonomers were around 1 kg/mol. The relatively modest total backbone degrees of polymerization ranged from ca. 20 to 40. Morphologies of these bottlebrush block polymers were characterized by small-angle X-ray scattering (SAXS). The PEP-PS diblocks exhibited only cylindrical (HEX) and lamellar (LAM) morphologies; the desired network phases did not appear in these materials, consistent with previous experimental studies. However, adding variable-length bottlebrush PEO blocks to diblocks containing 30% to 50% PS led to a substantial core-shell double gyroid (GYR) phase window in the ternary phase portrait. Encouragingly, the GYR unit cell dimensions increased almost linearly with the backbone degree of polymerization, portending the ability to access larger network dimensions than previously obtained with linear block polymers. This finding demonstrates a periodic network phase in bottlebrush block polymers for the first time and highlights extraordinary opportunities associated with applying facile ROMP chemistry to multiblock bottlebrush polymers.National Science Foundation, DMR-2011401U.S. Department of Energy Office of Science, DE-AC02-06CH11357Cui, Shuquan; Zhang, Bo; Shen, Liyang; Bates, Frank S; Lodge, Timothy P. (2023). Supporting data for Core−Shell Gyroid in ABC Bottlebrush Block Terpolymers. Retrieved from the University Digital Conservancy, https://doi.org/10.13020/reqb-y062
Poly(3-hexylthiophene)-block-poly(pyridinium phenylene)s: Block Polymers of p- and n-Type Semiconductors
No full textConjugated crystalline−crystalline donor−acceptor−donor block copolymer semiconductors, with regioregular poly(3-hexylthiophene) as a donor (p-type) block and poly(pyridinium pheneylene) as an acceptor (n-type) block within the backbone, were produced by sequential Grignard metathesis synthesis of poly(3-hexylthiophene), a Yamamoto-type cross-coupling polymerization−cyclization sequence. These conjugated block copolymers are soluble in organic solvents and display broad optical absorption bands extending close to the near-infrared region. They show reversible ambipolar redox properties with high electron affinities of 3.8−4.0 eV as well as useful ionization potentials of 5.1 eV that are characteristic of the respective blocks. Block copolymers from p- and n-type organic semiconductors are of interest for the formation of nanostructured bulk heterojunctions in photovoltaic devices.National Science Foundation (DMR-1005810)Toray Industries Inc
Money piece by Timothy P. Agnew, chief executive officer of the Finance Author
No full textMoney piece by Timothy P. Agnew, chief executive officer of the Finance Authority of Maine, about the increased availability of credit for Maine\u27s small businesses
Modularity and consciousness
No full textPartial contents Stream of consciousness -- Consciousness, science, and methodology -- The psychology of neuropsychology of consciousness -- Consciousness and content -- Function of consciousness -- Metaphysics of consciousness -- Subjectivity and explanatory gap -- The knowledge argument -- Qualia -- Higher-order monitoring conceptions of consciousness
Design of experiments with mixed effects and discrete responses plus related topics
No full textFor certain types of experiment, the response cannot be adequately modelled using a normal distribution. When this is the case, it is common to use a Generalised Linear Model (GLM) to analyse the data. Such models allow us to fit a wide range of response distributions including Bernoulli and Poisson.If responses in the same block are correlated, it may be appropriate to model the impact of blocking using random effects. The GLM can be extended in several ways to include random effects; both Generalised Linear Mixed Models (GLMMs) and Hierarchical Generalised Linear Models (HGLMs) are common examples of such extensions. Another example is a random intercept model for a binary response bioassay study with repeated measurements on heterogeneous individuals. The latter model is related to a GLMM but not strictly within that class.Obtaining designs for non-normal models with random effects is complicated by the fact that the information matrix, on which most optimality criteria are based, is computationally expensive to evaluate. Indeed, if one computes naively, the search for a typical optimal GLMM design is likely to take several months.When estimating GLMMs, it is common to use analytical approximations such as marginal quasi-likelihood (MQL) and penalised quasi-likelihood (PQL) in place of full maximum likelihood estimation. In Chapters 2 and 3, we consider the use of such computationally cheap approximations to construct surrogates for the information matrix when producing optimal designs. These reduce the computational burden substantially, enabling us to obtain designs within a practical time frame. The accuracy of the analytical approximations is explored through the use of a detailed computational approximation, which enables us to compute the optimal maximum likelihood design in the case where there are at most two points per block. It is found that one of the analytical approximations appears to perform consistently better than the others for the purposes of producing designs.In Chapters 4 and 5, designs for an individual variation bioassay model are obtained in the cases where (i) there is a single observation, or (ii) there are multiple observations, per individual. In the former case, designs on the basis of both maximum likelihood and analytical approximations are found and compared. In the multiple observation case, a restriction on the design space enables optimal designs to be computed using a computational approximation related to that for GLMMs. This involves extensive precomputation of numerical integrals.In Chapter 6 designs for HGLMs are studied using a computationally inexpensive asymptotic approximation to the variance-covariance matrix of the parameter estimators. This allows us to derive designs which are also efficient for the estimation of the random effects.Throughout, the dependence of the optimal design on the unknown values of the model parameters is addressed through the use of Bayesian methods, which codify uncertainty about the parameter values using a prior distribution. We often assess the performance of the designs obtained from the optimisation of a Bayesian objective function in terms of the distribution on the local efficiencies which is induced by the prior distribution.When the parameter space contains degenerate values, there is a problem with potential non-convergence of the Bayesian objective function used to select designs. This issue is explored in depth in Chapter 7, and results are obtained for a number of standard models
Timothy Meyer serves as a contributing author for UN report
No full textAssistant Professor Timothy Meyer served as a contributing author for the United Nations Industrial Development Organization\u27s report titled Networks for Prosperity: Connecting Development Knowledge Beyond 2015. The document, which was released during November, analyzes the nexus between the global connectedness of a country and its economic success, sustainability and government effectiveness. Meyer was one of only approximately 20 academic and practical experts from around the world selected to serve as a contributor after a global call for proposals.
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Selected Contributions of Sister Mary Berenice Beck, O.S.F. to Nursing in the United States, 1923-1956
No full textby Sister M. Timothy Costello.Typescript.Thesis (M.S.N.)--Catholic University of America.Bibliography: leaves 44-47.Also available in microfilm
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