cssi/SciSciGPT-SciSciNet huggingface dataset:
Isolation and characterization of the nuclear matrix from Zajdela ascites hepatoma cells.

A procedure is reported for the isolation of Zajdela ascites hepatoma nuclei which avoids the use of harsh detergents and citric acid. Marker enzyme analysis, chemical composition, and electron microscopy all indicated a high degree of purity and intactness. The proteinaceous nucleoskeletal structure termed the “nuclear matrix” was isolated from the hepatoma nuclei. Structurally, the isolated hepatoma matrix consisted of a surrounding residual nuclear envelope, residual nucleoli, and an extensive internal matrix structure. The internal matrix structure, moreover, revealed a remarkable resemblance to structures observed in the interchromatinic regions of intact hepatoma nuclei. Chemically, the matrix contained 77.9% protein, 19.6% RNA, 1.0% DNA, and 1.5% phospholipid. Nearly identical ultrastructure and composition is found for the corresponding matrices isolated from normal and regenerating liver cells. Although many differences were initially found in the polypeptide profiles of hepatoma and liver matrices, isolation in the presence of the protease inhibitors phenylmethylsulfonyl fluoride and sodium tetrathionate revealed that these apparent differences were largely due to differential degradation of matrix polypeptides. In the presence of protease inhibitors, only one qualitative difference was detected, a polypeptide with a molecular weight of 100,000 unique to the hepatoma matrix. In addition, several prominent quantitative differences were detected. Comparison of regenerating and normal liver matrix polypeptide profiles revealed no significant qualitative or quantitative differences.
Toward large-scale shallow semantics for higher-quality NLP

Building on the successes of the past decade's work on statistical methods, there are signs that continued quality improvement for QA, summarization, information extraction, and possibly even machine translation require more-elaborate and possibly even (shallow) semantic representations of text meaning. But how can one define a large-scale shallow semantic representation system and contents adequate for NLP applications, and how can one create the corpus of shallow semantic representation structures that would be required to train machine learning algorithms? This talk addresses the components required (including a symbol definition ontology and a corpus of (shallow) meaning representations) and the resources and methods one needs to build them (including existing ontologies, human annotation procedures, and a verification methodology). To illustrate these aspects, several existing and recent projects and applicable resources are described, and a research programme for the near future is outlined. Should NLP be willing to face this challenge, we may in the not-too-distant future find ourselves working with a whole new order of knowledge, namely (shallow) and doing so in increasing collaboration (after a 40-years separation) with specialists from the Knowledge Representation and reasoning community.
GLS estimation and empirical bayes prediction for linear mixed models with Heteroskedasticity and sampling weights : a background study for the POVMAP project

This note adapts results by Huang and Hidiroglou (2003) on Generalized Least Squares estimation and Empirical Bayes prediction for linear mixed models with sampling weights. The objective is to incorporate these results into the poverty mapping approach put forward by Elbers et al. (2003). The estimators presented here have been implemented in version 2.5 of POVMAP, the custom-made poverty mapping software developed by the World Bank.
Gamma-ray Pulsars: Models and Predictions

Pulsed emission from gamma-ray pulsars originates inside the magnetosphere, from radiation by charged particles accelerated near the magnetic poles or in the outer gaps. In polar cap models, the high energy spectrum is cut off by magnetic pair production above an energy that is, dependent on the local magnetic field strength. While most young pulsars with surface fields in the range B = 10(exp 12) - 10(exp 13) G are expected to have high energy cutoffs around several GeV, the gamma-ray spectra of old pulsars having lower surface fields may extend to 50 GeV. Although the gamma-ray emission of older pulsars is weaker, detecting pulsed emission at high energies from nearby sources would be an important confirmation of polar cap models. Outer gap models predict more gradual high-energy turnovers of the primary curvature emission around 10 GeV, but also predict an inverse Compton component extending to TeV energies. Detection of pulsed TeV emission, which would not survive attenuation at the polar caps, is thus an important test of outer gap models. Next-generation gamma-ray telescopes sensitive to GeV-TeV emission will provide critical tests of pulsar acceleration and emission mechanisms.
Assays for Determination of Protein Concentration

Biochemical analysis of proteins relies on accurate quantification of protein concentration. Detailed in this appendix are some commonly used methods for protein analysis, e.g., Lowry, Bradford, bicinchoninic acid (BCA), UV spectroscopic, and 3-(4-carboxybenzoyl)quinoline-2-carboxaldehyde (CBQCA) assays. The primary focus of this report is assay selection, emphasizing sample and buffer compatibility. The fundamentals of generating protein assay standard curves and of data processing are considered, as are high-throughput adaptations of the more commonly used protein assays. Also included is a rapid, inexpensive, and reliable BCA assay of total protein in SDS-PAGE sample buffer that is used for equal loading of SDS-PAGE gels. © 2016 by John Wiley & Sons, Inc.
A Bayesian approach to learning Bayesian networks with local structure

Recently several researchers have investigated techniques for using data to learn Bayesian networks containing compact representations for the conditional probability distributions (CPDs) stored at each node. The majority of this work has concentrated on using decision-tree representations for the CPDs. In addition, researchers typically apply non-Bayesian (or asymptotically Bayesian) scoring functions such as MDL to evaluate the goodness-of-fit of networks to the data. In this paper we investigate a Bayesian approach to learning Bayesian networks that contain the more general decision-graph representations of the CPDs. First, we describe how to evaluate the posterior probability-- that is, the Bayesian score--of such a network, given a database of observed cases. Second, we describe various search spaces that can be used, in conjunction with a scoring function and a search procedure, to identify one or more high-scoring networks. Finally, we present an experimentd evaluation of the search spaces, using a greedy algorithm and a Bayesian scoring function.
The closure of a linear space in a product of lines

Given a linear space L in affine space $${\mathbb {A}}^n$$An, we study its closure $$\widetilde{L}$$L~ in the product of projective lines $$({\mathbb {P}}^1)^n$$(P1)n. We show that the degree, multigraded Betti numbers, defining equations, and universal Grobner basis of its defining ideal $$I(\widetilde{L})$$I(L~) are all combinatorially determined by the matroid M of L. We also prove that $$I(\widetilde{L})$$I(L~) and all of its initial ideals are Cohen---Macaulay with the same Betti numbers, and can be used to compute the h-vector of M. This variety $$\widetilde{L}$$L~ also gives rise to two new objects with interesting properties: the cocircuit polytope and the external activity complex of a matroid.
Chromosomal 3 and 8 Status Within Hepatic Metastasis of Uveal Melanoma

Abstract Context.—Several studies have evaluated clinical, histopathologic, cytogenetic, and molecular prognostic variables in uveal melanoma. However, it is not known whether the primary tumor cells maintain these aggressive attributes at the metastatic sites. Objective.—To determine the status of chromosomes 3 and 8q and c-myc amplification using fluorescence in situ hybridization on hepatic metastatic lesions of primary uveal melanoma. Design.—Ten patients with uveal melanoma with needle core biopsy–confirmed hepatic metastasis. Representative paraffin blocks were selected based on review of hematoxylin-eosin–stained sections. Fluorescence in situ hybridization was performed for detection of monosomy 3 and amplification at the 8q24 MYC locus using standard methods. The tricolor chromosome enumeration probe 8 (CEP8)/ IGH/MYC and the Urovysion probe consisting of CEP3, CEP7, CEP17, and 9P21 probes were used. A total of 200 interphase cells were scored. Results.—Hepatic metastasis was confirmed in each ca...
A Framework for Regulating Microfinance Institutions : The Experience in Ghana and the Philippines

An earlier Policy Research Working Paper (Hennie van Greuning, Joselito Gallardo, and Bikki Randhawa, "A Framework for Regulating Microfinance Institutions," WPS 2061, February 1999) presented a regulatory framework that identifies thresholds in financial intermediation activities that trigger a requirement for a microfinance institution to satisfy external or mandatory guidelines-a tiered approach to regulation and prudential supervision. The model focuses on risk-taking activities of microfinance institutions that must be managed and prudentially regulated. The author reports on the results of the field testing and assessment of the tiered approach, focusing on the experience of Ghana and the Philippines. The two countries both have a wide range of informal, semi-formal, and formal institutions providing financial services to the poor, but differ in how they regulate financial intermediation activities by microfinance providers. In his assessment and a comparative analysis, the author focuses on key issues in the regulatory and supervisory environment for microfinance-and in the legal system and judicial processes-being addressed by government authorities and microfinance stakeholders in both countries. He gives particular attention to the thresholds at which intermediation activities become subject to prudential regulation and regulatory standards for capitalization and capital adequacy, asset quality and provisioning for nonperforming loans, and liquidity management. seeks to identify the key elements and characteristics of the microfinance regulatory experience of Ghana and the Philippines and to draw the lessons that may be useful for other countries interested in establishing a regulatory environment conducive to the development of sustainable microfinance institutions. The experience of Ghana and the Philippines shows that a transparent, inclusive regulatory framework is indispensable for enabling microfinance institutions to maintain market specialization and to pursue institutional development that leads to sustainability. Clear pathways for institutional transformation facilitate the integration of microfinance institutions into the formal financial system.
Towards a coherent theory of physics and mathematics.

As an approach to a Theory of Everything a framework for developing a coherent theory of mathematics and physics together is described. The main characteristic of such a theory is discussed: the theory must be valid and and sufficiently strong, and it must maximally describe its own validity and sufficient strength. The mathematical logical definition of validity is used, and sufficient strength is seen to be a necessary and useful concept. The requirement of maximal description of its own validity and sufficient strength may be useful to reject candidate coherent theories for which the description is less than maximal. Other aspects of a coherent theory discussed include universal applicability, the relation to the anthropic principle, and possible uniqueness. It is suggested that the basic properties of the physical and mathematical universes are entwined with and emerge with a coherent theory. Support for this includes the indirect reality status of properties of very small or very large far away systems compared to moderate sized nearby systems. Discussion of the necessary physical nature of language includes physical models of language and a proof that the meaning content of expressions of any axiomatizable theory seems to be independent of the algorithmic complexity of the theory. Godel maps seem to be less useful for a coherent theory than for purely mathematical theories because all symbols and words of any language must have representations as states of physical systems already in the domain of a coherent theory.
How children talk about a conversation

This study investigates how children of different ages talk about a conversation that they have witnessed. 48 Turkish children, five, nine and thirteen years in age, saw a televised dialogue between two Sesame Street characters (Bert and Ernie). Afterward, they narrated what they had seen and heard. Their reports were analysed for the development of linguistic devices used to orient their listeners to the relevant properties of a conversational exchange. Each utterance in the child's narrative was analysed as to its conversational role: (1) whether the child used direct or indirect quotation frames; (2) whether the child marked the boundaries of conversational turns using speakers' names and (3) whether the child used a marker for pairing of utterances made by different speakers (agreement-disagreement, request-refusal, questioning-answering). Within pairings, children's use of (a) the temporal and evaluative connectivity markers and (b) the kind of verb of saying were identified. The data indicate that there is a developmental change in children's ability to use appropriate linguistic means to orient their listeners to the different properties of a conversation. The development and use of these linguistic means enable the child to establish different social roles in a narrative interaction. The findings are interpreted in terms of the child's social-communicative development from being a ‘character’ to becoming a ‘narrator’ and ‘author’ of the reported conversation in the narrative situation.
Postcards from the NSF

We provide an overview of the workings of the National Science Foundation and the proposal review process, as well as some guidance in writing proposals for funding.
The GATT's Contribution to Economic Recovery in Post-War Western Europe

Introduction The contrast between the decade of economic instability in Western Europe after World War I and the economic recovery established in the decade following World War II is nowhere more evident than in the area of international trade relations. Economic reconstruction following World War I lacked any institutional mechanism to facilitate the reduction of trade barriers that had arisen during the war and had become entrenched thereafter. The political weakness of European countries in trade policy was evident when a proposal for “equality of trade conditions” in a draft League of Nations charter was rejected in favor of a weaker provision for “equitable treatment.” The World Economic Conference in 1927 still found it necessary to call upon governments to remove wartime controls on trade, which included import quotas, licensing requirements, and foreign exchange controls. A decade after its formation, the League of Nations had yet to sponsor any negotiations on liberalizing world trade from high tariffs, and the onset of the depression vanquished any serious prospect of trade reform in Europe and elsewhere. Yet during World War II, even in advance of official US participation in the conflict, the United States and the United Kingdom already envisioned a post-war world trading system based on reducing all trade barriers and limiting discriminatory tariff preferences. Just two years after Germany's surrender, twenty-three countries established a General Agreement on Tariffs and Trade (GATT) that set rules to restrict national trade policies and even started to decrease tariffs in binding agreements.
6D F-theory models and elliptically fibered Calabi-Yau threefolds over semi-toric base surfaces

We carry out a systematic study of a class of 6D F-theory models and associated Calabi-Yau threefolds that are constructed using base surfaces with a generalization of toric structure. In particular, we determine all smooth surfaces with a structure invariant under a single C∗ action (sometimes called “T-varieties” in the mathematical literature) that can act as bases for an elliptic fibration with section of a Calabi-Yau threefold. We identify 162,404 distinct bases, which include as a subset the previously studied set of strictly toric bases. Calabi-Yau threefolds constructed in this fashion include examples with previously unknown Hodge numbers. There are also bases over which the generic elliptic fibration has a Mordell-Weil group of sections with nonzero rank, corresponding to non-Higgsable U(1) factors in the 6D supergravity model; this type of structure does not arise for generic elliptic fibrations in the purely toric context.
State financial institutions : mandates, governance, and beyond

There is no doubt that on average the performance of state financial institutions around the world has been below the lowest expectations. Lack of governance, management skills, regulation, and transparency, and misguided incentives have contributed to discredit these institutions for supporting the development of local financial markets. However, the pro-active role that some state financial institutions have played in the recent crisis in allocating credit to sectors cyclically not attractive for commercial banks has brought back the question of whether some state ownership in the banking system would be preferable. This paper analyzes the experience of four state financial institutions that have performed relatively well in the past: Canada's Business Development Bank, Chile's BancoEstado, South Africa's Development Bank of Southern Africa, and Finland's Finnvera plc. The author finds that these institutions have different checks and balances to mitigate eventual mismanagement of resources. The author also finds that little progress has been made in measuring the policy performance of these institutions.
El Niño–Southern Oscillation extrema in the Holocene and Last Glacial Maximum

[1] The El Nino–Southern Oscillation (ENSO) is the largest engine of interannual climate variability on the planet, yet its past behavior and potential for future change are poorly understood and vigorously contested. Reconstructions of past ENSO are indispensable for testing climate models tasked with predicting future ENSO activity in a warming world, but suitable geologic archives are scarce, especially for the last glacial period. Here we reconstruct mean climate and ENSO variability in the Holocene and Last Glacial Maximum (LGM) from oxygen isotopic ratios (δ18O) of individual foraminifera retrieved from deep-sea sediments. Our results document coordinated adjustments of the tropical Pacific/ENSO system between two diametrically opposite states: an “amplified ENSO” state in the LGM associated with a reduced zonal temperature gradient, and a “damped ENSO” state in the Mid-Holocene with enhanced gradient. Orbital precession provided the switch between these states and acted as the dominant external driver of the tropical Pacific/ENSO system in the past 25,000 years. The linked response of the mean state and variability to orbital forcing provides an integrated framework for testing ENSO theory and models.
The Structure of the American Economy

We explore the relationship between input-output accounts and the national revenue function. The generalized inverse of an economy’s technology matrix carries information relating changes in endowments with changes in outputs; its transpose relates output prices and factor prices. Our primary theoretical contribution is to derive an economy’s revenue function for an arbitrary Leontief technology. Our main empirical contribution is to compute the national revenue function for the American economy in 2003 and to describe its properties. We implement our ideas using two different models: one where all factors are mobile and another with capital specific to each sector in the economy.
Dynamic Scoring in a Romer-Style Economy

This article analyzes how changes in tax rates affect government revenue in a Romer-style endogenous growth model. Lower tax rates on financial income (returns to physical capital and intellectual property) are partially self-financing primarily because lower financial income taxes stimulate innovation and enhance labor productivity in the long run. In the baseline calibration, about half of a tax cut is self-financing in the long run, substantially more than in the Ramsey model. The dynamics of the economy's response to a tax cut are very sluggish and, for some variables, nonmonotonic.
Games of Capacity Manipulation in Hospital-Intern Markets

In this paper, we analyze capacity manipulation games in hospital-intern markets inspired by the real-life entry-level labor markets for young physicians who seek residencies at hospitals. In a hospital-intern market, the matching is determined by a centralized clearinghouse using the preferences revealed by interns and hospitals and the number of vacant positions revealed by hospitals. We consider a model in which preferences of hospitals and interns are common knowledge. Hospitals play a capacity-reporting game. We analyze the equilibria of the game-form under the two most widely used matching rules: hospital-optimal and intern-optimal stable rules. We show that (i) there may not be a pure strategy equilibrium in general; and (ii) when a pure strategy equilibrium exists, every hospital weakly prefers this equilibrium outcome to the outcome of any larger capacity profile. Finally, we present conditions on preferences to guarantee the existence of pure strategy equilibria.
Saturation for a General Class of Models

Implicit techniques for construction and representation of the reachability set of a high-level model have become quite efficient for certain types of models. In particular, previous work developed a "saturation" algorithm that exploits asynchronous behavior to efficiently construct the reachability set using multiway decision diagrams, but using a Kronecker product expression to represent each model event. For models whose events do not naturally fall into this category, use of the saturation algorithm requires adjusting the model by combining components or splitting events into subevents until a Kronecker product expression is possible. In practice, this can lead to additional overheads during reachability set construction. This paper presents a new version of the saturation algorithm that works for a general class of models: models whose events are not necessarily expressible as Kronecker products, models containing events with complex priority structures, and models whose state variables have unknown bounds. Experimental results are given for several examples
Substernal goiters and sternotomy.

Objective: To determine what factors predispose patients with retrosternal goiters to median sternotomy. Study Design: Retrospective review. Methods: Analysis of a single surgeon experience with 113 substernal goiters operated upon during a 10-year period. Results: 108 goiters were successfully removed through a cervical approach. Four patients required sternotomy, and it was concluded that one patient who did not receive sternotomy might have been better managed with sternotomy. Factors that led to sternotomy were malignancy, involvement of the posterior mediastinum, extensive substernal extension, and the presence of an ectopic nodule. The latter two were the most important factors. Revision surgery and tracheal compression did not influence the need for sternotomy. Conclusions: On the basis of preoperative imaging, it is possible to predict which patients with retrosternal goiters are likely to require median sternotomy. These factors are malignancy, extension into the posterior mediastinum, substernal extension inferior to the level of the aortic arch, and the lack of a solid attachment between the cervical and mediastinal components of the thyroid gland. Although previously reported, the latter factor has not received sufficient recognition in the management of retrosternal goiter. Laryngoscope, 2009
M(atrix)-theory in various dimensions

Abstract We demonstrate the precise numerical correspondence between long range scattering of supergravitons and membranes in supergravity in the infinite momentum frame and in M(atrix)-theory, both in 11 dimensions and for toroidal compactifications. We also identify wrapped membranes in terms of topological invariants of the vector bundles associated to the field theory description of compactified M(atrix)-theory. We use these results to check the realization of T-duality in M(atrix)-theory.
Economic forces shaping investment in office markets

Divides investors into two types: tax‐paying investors and tax‐exempt pension funds. Tax‐paying investors will worry about the expected after‐tax variance of return on real estate, while tax‐exempt pension funds will worry about the expected pre‐tax variance of return. States this is an important observation because the after‐tax variance of return is apt to be significantly less than the pre‐tax variance of return (particularly during the early 1980s when tax‐paying investors were able to use real estate losses to offset other income). The model developed by the author suggests this reduced expected after‐tax variance of return helps explain the seemingly irrational construction that took place in US office markets during the 1980s.
Fabrication of Mesoporous CdTe/ZnO@SiO2 Core/Shell Nanostructures with Tunable Dual Emission and Ultrasensitive Fluorescence Response to Metal Ions

In this paper, we demonstrated the encapsulation of CdTe quantum dots (QDs) and ZnO nanorods (NRs) with a layer of mesoporous SiO2 shell (pore size: 4.1 nm) for the purpose of integrating dual-emission property into one common nanostructure. Within the core−shell CdTe/ZnO@SiO2 nanocomposites, CdTe QDs and ZnO NRs provide visible emission and UV emission, respectively. The fluorescence intensity ratio of the dual emission can be tuned by altering the hydrolysis time of tetraethyl orthosilicate (TEOS). The core−shell CdTe/ZnO@SiO2 nanocomposites exhibit very interesting photoluminescent behaviors after interactions with heavy-metal ions such as Hg2+, Pb2+, and Cu2+. The visible emission contributed by CdTe QDs was abnormally enhanced in a range of 20−90% at the concentration of Hg2+ < 10−8 M, Pb2+ < 10−5 M, and Cu2+ < 10−6 M, whereas the intensity of UV emission by ZnO NRs was kept constant in all cases. Consequently, the UV emission may serve as a reference. The mechanism of the fluorescence enhancement is...
Alternative Evaluation of a ln tan Integral Arising in Quantum Field Theory

A certain dilogarithmic integral I 7 turns up in a number of contexts including Feynman diagram calculations, volumes of tetrahedra in hyperbolic geometry, knot theory, and conjectured relations in analytic number theory. We provide an alternative explicit evaluation of a parameterized family of integrals containing this particular case. By invoking the Bloch–Wigner form of the dilogarithm function, we produce an equivalent result, giving a third evaluation of I 7. We also alternatively formulate some conjectures which we pose in terms of values of the specific Clausen function Cl2.
Vertical Shearing Instabilities in Radially Shearing Disks: The Dustiest Layers of the Protoplanetary Nebula

Gravitational instability of a vertically thin, dusty sheet near the midplane of a protoplanetary disk has long been proposed as a way of forming planetesimals. Before Roche densities can be achieved, however, the dust-rich layer, sandwiched from above and below by more slowly rotating dust-poor gas, threatens to overturn and mix by the Kelvin-Helmholtz instability (KHI). Whether such a threat is real has never been demonstrated: the Richardson criterion for the KHI is derived for two-dimensional Cartesian shear flow and does not account for rotational forces. Here we present three-dimensional numerical simulations of gas-dust mixtures in a shearing box, accounting for the full suite of disk-related forces: the Coriolis and centrifugal forces, and radial tidal gravity. Dust particles are assumed small enough to be perfectly entrained in gas; the two fluids share the same velocity field but obey separate continuity equations. We find that the Richardson number Ri does not alone determine stability. The critical value of Ri below which the dust layer overturns and mixes depends on the height-integrated metallicity Σd/Σg (surface density ratio of dust to gas). Nevertheless, for Σd/Σg between 1 and 5 times solar, the critical Ri maintains a nearly constant value of ~0.1. Keplerian radial shear stabilizes those modes that would otherwise disrupt the layer at large Ri. If the height-integrated metallicity is at least ~5 times greater than the solar value of 0.01, then midplane dust densities can approach Roche densities. Such a metal-rich environment might be expected to produce gas giant planets having similarly supersolar metallicities.
String corrections to four point functions in the AdS / CFT correspondence

Abstract In a string calculation to order α ′ 3 , we compute an eight-derivative four-dilaton term in the type IIB effective action. Following the AdS prescription, we compute the order ( g YM 2 N c ) −3/2 correction to the four-point correlation function involving the operator tr F 2 in four dimensional N =4 super Yang-Mills using the string corrected type IIB action extending the work of Freedman et al. (hep-th/9808006). In the limit where two of the Yang-Mills operators approach each other, we find that our correction to the four-point correlation functions develops a logarithmic singularity. We discuss the possible cancellation of this logarithmic singularities by conjecturing new terms in the type IIB effective action.
Deterministic representation of chaos in classical dynamics

Chaos in an Anosov-type mechanical system is eliminated by referring the governing equations to a specially selected rapidly oscillating (non-inertial) frame of reference in which the stabilization effect is caused by inertia forces. The result is generalized to any orbitally unstable mechanical system.
Structured imagination: The role of category structure in exemplar generation.

Abstract College students imagined animals that might live on a planet somewhere else in the galaxy. In the first experiment, they provided drawings and descriptions of their initial imagined animal, another member of the same species, and a member of a different species. The majority of imagined creatures were structured by properties that are typical of animals on earth: bilateral symmetry, sensory receptors, and appendages. Subjects also allowed shape, appendages and sense receptors to vary often across species but rarely within species. In Experiment 2, subjects′ creations were influenced by correlated attributes; those told that the animal was feathered were more likely to produce creatures with wings and beaks, and those told it lived in water and had scales were more likely to produce creatures with fins and gills relative to subjects who were told the animal was furry or who were given no specific features. Experiments 3 and 4 revealed that many subjects approach the task by retrieving exemplars of known earth animals, but that instructions and task constraints can lead to greater use of broader knowledge frameworks. Experiment 5 revealed that the structuring found in college students′ imagined animals also holds for extraterrestrials developed by science fiction writers. The results are consistent with the idea that similar structures and processes underlie creative and noncreative aspects of cognition, and are discussed in terms of the concept of structured imagination . That is, when subjects create a new member of a known category for an imaginary setting, their imagination is structured by a particular set of properties that are characteristic of that category.
Study of the Crystal Structures and Nonstoichiometry in the System Cs3Sc2Cl9-CsScCl3

The phase Cs/sub 3/Sc/sub 2/Cl/sub 9/ has the Cs/sub 3/Tl/sub 2/Cl/sub 9/ type structure (R anti 3c, a = 12.707 (2) A, c = 18.117 (4) A) rather than the chromium(III) structure type common to the remainder of the 3d elements. The /sup 45/Sc NMR spectra of ScCl/sub 3/ and of Cs/sub 3/Sc/sub 2/Cl/sub 9/, which has been slowly cooled in comparison with that quenched from the melt and annealed, establish that the ternary compound melts somewhat incongruently. Reduction of the scandium(III) phase at elevated temperatures by metal gives CsScCl/sub 3/ which has the CsNiCl/sub 3/ structure (hexagonal perovskite, P6/sub 3//mmc, a = 7.350 (2) A, c = 6.045 (3) A). The close relationship between the two structures, strings of scandium pairs alternating with vacancies in Cs/sub 3/Sc/sub 2/Cl/sub 9/ and fully occupied strings of metal in the reduced limit, allows for an apparent region of nonstoichiometry between the two without x-ray evidence for superstructure ordering of vacancies. Values of R = 0.055 and R/sub w/ = 0.064 were obtained by least-squares refinement of 108 independent reflections from a single crystal with a refined average scandium occupancy of 0.79 (3). Limited refinement of anti 3m-symmetry diffraction data from the samemore » crystal reveals that the scandium atoms are probably unevenly distributed, namely, as fully occupied pairs with random fractional occupancy of the third site. Precise Guinier powder diffraction data suggest that all scandium sites become crystallographically equivalent above about 87 to 90% average occupancy. The blue CsScCl/sub 3/ is probably a semiconductor rather than a metallic compound. 4 figures, 3 tables.« less
AC‐Drive‐Enhanced Relaxor Characteristics and Domain Breakdown in Ferroelectrics Containing Quenched Impurities

The dielectric constant has been measured for various compositions in the (Pb1-3/2yLay)(Zr0.65Ti0.35)O3 solution as a function of AC-drive amplitude. These studies have shown the presence of strong nonlinearities and enhanced relaxor characteristics with increasing AC drive. Corresponding transmission electron microscopy investigations demonstrated an enhanced breakdown of ferroelectric domains. Polarization studies revealed linearity in the range of field strengths investigated, demonstrating that the dielectric nonlinearities are not due to intrinsic polarization switching, but rather to the dynamics of various domainlike states. In the disordered condition, evidence is then presented which demonstrates a mesoscale freeze-out of polar clusters.
SYNTHESIS OF 2-CYANOMETHYL-1-METHYLPIPERIDINE

Abstract An improved method for the synthesis of 2-cyanomethyl-1-methylpiperidine is reported.
Random Vectors in the Isotropic Position

Abstract Letybe a random vector in R n, satisfying E y⊗y=id. LetMbe a natural number and lety1, …, yMbe independent copies ofy. We study the question of approximation of the identity operator by finite sums of the tensorsyi⊗yi. We prove that for some absolute constantC E 1 M ∑ i=1 M y i ⊗y i −id ⩽C· log n M ·( E ‖y‖ log M ) 1/log M , provided that the last expression is smaller than 1. We apply this estimate to improve a result of Bourgain concerning the number of random points needed to bring a convex body into a nearly isotropic position.
Measurement of Turbine Blade-Tip Rotordynamic Excitation Forces

This paper presents results of a program to investigate the magnitude, origin, and parametric variations of destabilizing forces that arise in high power turbines due to blade-tip leakage effects. Five different unshrouded turbine configurations and one configuration shrouded with a labyrinth seal were tested with static offsets of the turbine shaft. The forces along and perpendicular to the offset were measured directly with a dynamometer and were also inferred from velocity triangles and pressure distributions obtained from detailed flow surveys. These two routes yielded values in fair agreement in all cases. For unshrouded turbines, the cross-forces are seen to originate mainly (∼ 2/3) from the classical Alford mechanism (nonuniform work extraction due to varying blade efficiency with tip gap) and about 1/3 from a slightly skewed hub pressure pattern. The direct forces arise mainly (3/4) from this pressure pattern, with the rest due to a slight skewness of the Alford mechanism. The pressure nonuniformity (lower pressures near the widest gap) is seen to arise from a large-scale redistribution of the flow as it approaches the eccentric turbine. The cross-fbrces are found to increase substantially when the gap is reduced from 3.0 to 1.9 percent of blade height, probably due to viscous blade-tip effects. The forces also increase when the hub gap between stator and rotor decreases. The force coefficient decreases with operating flow coefficient. In the case of the shrouded turbine, most of the forces arise from nonuniform seal pressures. This includes about 80 percent of the transverse forces. The rest appears to come from uneven work extraction (Alford mechanism). Their level is about 50 percent higher than in the unshrouded cases.
Multiline model for the e-beam pumped XeF(B-X) laser

A multivibronic- line, rate-equation model for prediction of e-beam pumped XeF laser performance is described. It self-consistently treats the temporal evolution of the gas and electron temperatures as well as the densities of atomic and molecular species, electrons, and several laser transitions. By correlating species density calculations with observed narrowband absorption data in Ne/Xe plasmas and by invoking certain physical considerations, it is shown that the strong narrowband (AX ~ 2 nm) absorption near 351 nm can be reasonably correlated with a neon excimer species. By judicious adjustment of selected rate constants within their range of uncertainty, it has been possible to obtain good agreement with experimental data on pressure- and mixdependent fluorescence efficiency and also temperature- and wavelength-dependent absorption and small signal gain over a wide range of medium operating conditions. Subsequent predictions of temperature dependent laser efficiency and spectra are found to be in good agreement with available data.
Spectral function and conductivity in the normal state of the cuprates: A spin fluctuation study

We study the spectral function Ak(v) and the optical conductivity s 1(v) for a system of fermions interacting with their collective spin fluctuations ~the spin-fermion model!, and apply the results to optimally doped cuprates in the normal state. We show that there is no qualitative distinction between hot and cold regions in the Brillouin zone—in both cases, there exists a wide range of frequencies where the width of the peak in Ak(v) scales linearly with v. We demonstrate that s 1(v) is inversely linear in v up to very high frequencies. We argue that the slopes of Ak(v) and s 1(v) agree quantitatively with the photoemission and optical data for Bi2212.
Smith normal forms of incidence matrices

A brief introduction is given to the topic of Smith normal forms of incidence matrices. A general discussion of techniques is illustrated by some classical examples. Some recent advances are described and the limits of our current understanding are indicated.
A Simple Synthesis of 1-Methylcyclobutene

Abstract Controlled thermal decomposition of the sodium salt of cyclopropyl methyl ketone tosylhydrazone gives 1-methylcyclobutene of excellent purity in good yield.
Borostannylation of alkynes and enynes. Scope and limitations of the reaction and utility of the adducts.

The utility of the hetero-bismetallating reagent 1,3-dimethyl-2-trimethylstannyl-2-bora-1,3-diazacyclopentane (1) has not been fully realized because of the hydrolytic instability of the products derived from catalyzed vicinal syn-additions to alkynes. The isolation of a variety of such adducts derived from alkynes (and also from hitherto unreported additions to 1,3-enynes) as stable boron pinacolates is reported. Examples of the applications of resulting products in tandem cross-coupling reactions and as dienes in Diels-Alder reactions are illustrated. While exploring the applications of hetero-bismetallative cyclization of R,ω-diynes using 1,3-dimethyl-2-trimethylstannyl-2-bora-1,3-diazacyclopentane 1 (eq 1) in the synthesis of highly functionalized dibenzocyclooctadienes, 1 it became apparent that except for low molecular weight adducts where the products can be isolated by distillation, or in rare cases where they are crystalline, the hydrolytic instability of the primary [BSn] adducts severely limits the utility of this otherwise useful reagent. 2 Further impetus for work in the area came from our recent recognition that, despite the extreme sensitivity to moisture and difficulties in its preparation, this reagent could have a much broader substrate scope and improved selectivity in its reactions as compared to the more well-known silylstannanes. 3 Even though both reagents undergo regio- and stereoselective 1,2-addition to terminal alkynes, giving products in which the stannyl residue is attached to the internal carbon, only the [BSn] reagent reacts with internal alkynes. In this paper, we provide examples of a simple protocol for the isolation of the borylstannyl alkenes derived from acetylene, mono- and disubstituted alkynes, and enynes. Also illustrated are examples of applications of the products derived from these reactions, including tandem Stille/Suzuki coupling reactions and the use of a highly
An empirical analysis of the role of China's exports on CO2 emissions

China is one of the world’s most rapidly growing countries and the largest consumer of energy in the world. As a result, China’s pollution emissions almost doubled from 2002 to 2007, and in 2006 it surpassed the United States to become the world’s top carbon dioxide emitter. Understanding the sources of emissions is essential towards designing policies aimed at curbing carbon emissions in China. The surge in China’s exports has been partially blamed for this increase in emissions. To understand the sources of emissions, this study uses a vector autoregression model to examine the relationship among exports, CO2 emissions, coal consumption and trade openness in China for the years 1970–2010. The study uses a modified version of Granger Causality developed by Toda and Yamamoto [56]. The main findings within the study indicate: (1) Granger Causality running from exports to emissions; (2) Granger Causality running from coal consumption to exports; and (3) GDP determines future variability in exports and CO2 emissions. Results suggest that governmental policies aimed at controlling coal consumption could affect CO2 emissions and exports. Results from this study should assist in formulating policies to mitigate both CO2 emissions and coal consumption.
NASA Glenn's Contributions to Aircraft Engine Noise Research

This report reviews all engine noise research conducted at the NASA Glenn Research Center over the past 70 years. This report includes a historical perspective of the Center and the facilities used to conduct the research. Major noise research programs are highlighted to show their impact on industry and on the development of aircraft noise reduction technology. Noise reduction trends are discussed, and future aircraft concepts are presented. Since the 1960s, research results show that the average perceived noise level has been reduced by about 20 decibels (dB). Studies also show that, depending on the size of the airport, the aircraft fleet mix, and the actual growth in air travel, another 15 to 17 dB reduction will be required to achieve NASA's long-term goal of providing technologies to limit objectionable noise to the boundaries of an average airport.
Non-supersymmetric deformations of the dual of a confining gauge theory

We introduce a computational technique for studying non-supersymmetric deformations of domain wall solutions of interest in AdS/CFT. We focus on the Klebanov-Strassler solution, which is dual to a confining gauge theory. From an analysis of asymptotics we find that there are three non-supersymmetric deformations that leave the ten-dimensional supergravity solution regular and preserve the global bosonic symmetries of the supersymmetric solution. Also, we show that there are no regular near-extremal deformations preserving the global symmetries, as one might expect from the existence of a gap in the gauge theory.
Argonaute-Bound Small RNAs from Promoter-Proximal RNA Polymerase II

Argonaute (Ago) proteins mediate posttranscriptional gene repression by binding guide miRNAs to regulate targeted RNAs. To confidently assess Ago-bound small RNAs, we adapted a mouse embryonic stem cell system to express a single epitope-tagged Ago protein family member in an inducible manner. Here, we report the small RNA profile of Ago-deficient cells and show that Ago-dependent stability is a common feature of mammalian miRNAs. Using this criteria and immunopurification, we identified an Ago-dependent class of noncanonical miRNAs derived from protein-coding gene promoters, which we name transcriptional start site miRNAs (TSS-miRNAs). A subset of promoter-proximal RNA polymerase II (RNAPII) complexes produces hairpin RNAs that are processed in a DiGeorge syndrome critical region gene 8 (Dgcr8)/Drosha-independent but Dicer-dependent manner. TSS-miRNA activity is detectable from endogenous levels and following overexpression of mRNA constructs. Finally, we present evidence of differential expression and conservation in humans, suggesting important roles in gene regulation.
Investigations into the plasma spray process

Abstract We have previously described a simple analytical model which was developed to examine momentum and thermal transfer from the plasma jet to the particles in a low pressure plasma spray deposition process. This model correctly predicted the experimentally observed maximum in particle acceleration at intermediate chamber pressures. The calculated results were in good agreement with experimentally measured particle velocities. In the present study, this model has been used to investigate the effects of particle size and mass density on particle velocity. The model has also been used to explore the effect of variations in selected process parameters on the thermal response of the particles. The analytical and experimental results for particle velocity are again in good agreement, with substantially lower acceleration rates and lower peak velocities for larger, more massive particles. The results of the thermal calculations indicate that particle melting is influenced by many parameters. Better particle melting is achieved at higher chamber pressures. Detailed thermal data which would verify the thermal model are not yet available; however, the predictions of the thermal model appear to be in qualitative agreement with empirically developed spray conditions for good particle melting. The model indicates that difficulties in melting refractory materials at very low chamber pressures are related to decreased plasma temperatures and plasma densities at low chamber pressures.
Closed strings from decaying D-branes

We compute the emission of closed string radiation from homogeneous rolling tachyons. For an unstable decaying Dp-brane the radiated energy is infinite to leading order for p ≤ 2 and finite for 2$>p > 2. The closed string state produced by a decaying brane is closely related to the state produced by D-instantons at a critical Euclidean distance from t = 0. In the case of a D0 brane one can cutoff this divergence so that we get a finite energy final state which would be the state that the brane decays into.
The Penrose Limit of AdS×S Space and Holography

In the Penrose limit, AdS×S space turns into a Cahen–Wallach (CW) space whose Killing vectors satisfy a Heisenberg algebra. This algebra is mapped onto the holographic screen on the boundary of AdS. We show that the Heisenberg algebra on the boundary of AdS may be obtained directly from the CW space by appropriately constraining the states defined on it. The transformations generated by the constraint are similar to gauge transformations. The "holographic screen" on the CW space is thus obtained as a "gauge-fixing" condition.