3,743 research outputs found

    Computational wing optimization and comparisons with experiment for a semi-span wing model

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    A computational wing optimization procedure was developed and verified by an experimental investigation of a semi-span variable camber wing model in the NASA Ames Research Center 14 foot transonic wind tunnel. The Bailey-Ballhaus transonic potential flow analysis and Woodward-Carmichael linear theory codes were linked to Vanderplaats constrained minimization routine to optimize model configurations at several subsonic and transonic design points. The 35 deg swept wing is characterized by multi-segmented leading and trailing edge flaps whose hinge lines are swept relative to the leading and trailing edges of the wing. By varying deflection angles of the flap segments, camber and twist distribution can be optimized for different design conditions. Results indicate that numerical optimization can be both an effective and efficient design tool. The optimized configurations had as good or better lift to drag ratios at the design points as the best designs previously tested during an extensive parametric study

    Autism, Social Comprehension, and Cognitive Impenetrability

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    Autism is a neurodevelopmental disorder featuring severe social and communicative deficits. Cognitive impenetrability is the inability of systems to be affected by an individual’s beliefs and desires. Individuals with autism have delayed performance on mindreading tasks. Mindreading is the interpretation of others which enables successful social interactions. This task performance is not correlated with everyday social function in autism. These deficits are in contrast with general intelligence and reasoning abilities within the normal range, resistant to cognitive behavioral training, and partially attributable to atypical social predispositions. This suggests individuals with autism perform social tasks differently than typicals. I argue that this mindreading deficit is cognitively impenetrable, then position this deficit within a theoretical framework, enactivism, emphasizing cognitive embodiment and inseparability of social comprehension and action. This framework helps explain the cognitive impenetrability of these social deficits by locating failure to penetrate in individuals\u27 failure to properly interact with the environment

    Investigation of stress corrosion cracking of titanium alloys Semiannual progress report, 1 Jun. - 30 Nov. 1966

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    Stress corrosion cracking mechanisms in titanium alloy foil

    Cylindrical contact homology of 3-dimensional Brieskorn manifolds

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    Cylindrical contact homology is a comparatively simple incarnation of symplectic field theory whose existence and invariance under suitable hypotheses was recently established by Hutchings and Nelson. We study this invariant for a general Brieskorn 3-manifold Σ(a1,,an)\Sigma(a_1,\ldots, a_n), and give a complete description of the cylindrical contact homology for this 3-manifold equipped with its natural contact structure, for any aja_j satisfying 1a1++1an<n2\frac{1}{a_1} + \cdots + \frac{1}{a_n} < n-2

    Dramatic expansion of the black widow toxin arsenal uncovered by multi-tissue transcriptomics and venom proteomics.

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    BackgroundAnimal venoms attract enormous interest given their potential for pharmacological discovery and understanding the evolution of natural chemistries. Next-generation transcriptomics and proteomics provide unparalleled, but underexploited, capabilities for venom characterization. We combined multi-tissue RNA-Seq with mass spectrometry and bioinformatic analyses to determine venom gland specific transcripts and venom proteins from the Western black widow spider (Latrodectus hesperus) and investigated their evolution.ResultsWe estimated expression of 97,217 L. hesperus transcripts in venom glands relative to silk and cephalothorax tissues. We identified 695 venom gland specific transcripts (VSTs), many of which BLAST and GO term analyses indicate may function as toxins or their delivery agents. ~38% of VSTs had BLAST hits, including latrotoxins, inhibitor cystine knot toxins, CRISPs, hyaluronidases, chitinase, and proteases, and 59% of VSTs had predicted protein domains. Latrotoxins are venom toxins that cause massive neurotransmitter release from vertebrate or invertebrate neurons. We discovered ≥ 20 divergent latrotoxin paralogs expressed in L. hesperus venom glands, significantly increasing this biomedically important family. Mass spectrometry of L. hesperus venom identified 49 proteins from VSTs, 24 of which BLAST to toxins. Phylogenetic analyses showed venom gland specific gene family expansions and shifts in tissue expression.ConclusionsQuantitative expression analyses comparing multiple tissues are necessary to identify venom gland specific transcripts. We present a black widow venom specific exome that uncovers a trove of diverse toxins and associated proteins, suggesting a dynamic evolutionary history. This justifies a reevaluation of the functional activities of black widow venom in light of its emerging complexity

    The behaviour of tobacco varieties in Western Australia

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    With the advent of a number of new varieties into the district, several problems have arisen, and this article is being written in an endeavour to set down just what is known of the varieties being tested. In order to make definite recommendations regarding a certain variety of tobacco, it requires to be tested under a wide range of soil and climatic conditions. To cover as wide a range of weather conditions as possible, the variety needs to be grown for three years before any real recommendation is warranted. To cover a wide range of soil types, trials have been conducted in several areas over the past two years and results are being accumulated

    Safe From Subpoena? The Importance of Certificates of Confidentiality to the Viability and Ethics of Research

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    This Article addresses legal issues related to Certificates, recognizes that Certificates face an uncertain future if challenged in court—based on the statutory history and limited relevant case law—and proposes that changes should be made to ensure Certificates actually offer the protection they promise. Part II reviews the background of Certificates of Confidentiality. Part III explores how Certificates fulfill vital functions by encouraging research participation, satisfying ethical obligations of researchers to protect participant data, and promoting the accuracy of data provided by participants in research studies. Part IV observes that the case law relevant to Certificates of Confidentiality, though limited, presents cause for concern. Part V explores the potential threats to Certificates of Confidentiality. Part VI argues that, for legal and public policy reasons, courts and Congress should consider changes in the way they approach Certificates of Confidentiality in order to offer broad protection for participants involved in sensitive research studies. Additionally, this section provides recommendations for researchers to secure sensitive data

    Microfluidic stochastic confinement enhances analysis of rare cells by isolating cells and creating high density environments for control of diffusible signals

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    Rare cells can be difficult to analyze because they either occur in low numbers or coexist with a more abundant cell type, yet their detection is crucial for diagnosing disease and maintaining human health. In this tutorial review, we introduce the concept of microfluidic stochastic confinement for use in detection and analysis of rare cells. Stochastic confinement provides two advantages: (1) it separates rare single cells from the bulk mixture and (2) it allows signals to locally accumulate to a higher concentration around a single cell than in the bulk mixture. Microfluidics is an attractive method for implementing stochastic confinement because it provides simple handling of small volumes. We present technologies for microfluidic stochastic confinement that utilize both wells and droplets for the detection and analysis of single cells. We address how these microfluidic technologies have been used to observe new behavior, increase speed of detection, and enhance cultivation of rare cells. We discuss potential applications of microfluidic stochastic confinement to fields such as human diagnostics and environmental testing

    Symmetrically H-Bridged Dimer of 2-Carboxylatobenzenediazonium. The 1:1 Complex between 2-Carboxybenzenediazonium Chloride and Benzenediazonium-2-carboxylate

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    The two zwitterions in the H-bridged dimer of 2-carboxylatobenzenediazonim (1) are linked by a crystallographically symmetric O&ctdot;Hctdot;O hydrogen bond with an O&ctdot;O distance of 2.436 (3) Å. Comparison of the (1) with the other benzenediazonium salts shows that the phenyl ring distortions in (1) are determined primarily by the diazonium substituent with only modest additional effects by the carboxylato group. Intramolecular neighboring goup interactions between the N2 group and the orthoCOO(H) group are indicated and are discussed. The terminal N atom of the diazonium group is bent away from the neighboring carboxylato group. The N2 and the carboxylato group are on the opposite sides of the best plane of the aromatic ring. Importantly, the carboxylato group is not fully conjugated with the aromatic ring but instead is rotated 6.5 (2)° around the C-CO2 axis in a fashion that suggest minimization of intramolecular repulsion between Nα and the proximate O atom and optimization of the inter-molecular hydrogen bonding
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