cssi/SciSciGPT-SciSciNet huggingface dataset:
DESILYLATION OF TBDMS ETHERS OF PHENOLS SUSCEPTIBLE TO POLYMERIZATION

A mild, efficient method for the desilylation of TBDMS groups of silyl ethers of acid- and base-sensitive p-hydroxybenzylidine and polyhydroxyphenols is described.
Computation in Sofic Quantum Dynamical Systems

We analyze how measured quantum dynamical systems store and process information, introducing sofic quantum dynamical systems. Using recently introduced information-theoretic measures for quantum processes, we quantify their information storage and processing in terms of entropy rate and excess entropy, giving closed-form expressions where possible. To illustrate the impact of measurement on information storage in quantum processes, we analyze two spin-1 sofic quantum systems that differ only in how they are measured.
Algebras Stratified for all Linear Orders

In this paper we describe several characterizations of basic finite-dimensional $\Bbbk$ -algebras A stratified for all linear orders, and classify their graded algebras as tensor algebras satisfying some extra property. We also discuss whether for a given linear order $\preccurlyeq$ , $\mathcal{F} (_{\preccurlyeq} \Delta)$ , the category of A-modules with $_{\preccurlyeq} \Delta$ -filtrations, is closed under cokernels of monomorphisms, and classify quasi-hereditary algebras satisfying this property.
Direct β-Alkylation of Aldehydes via Photoredox Organocatalysis

Direct β-alkylation of saturated aldehydes has been accomplished by synergistically combining photoredox catalysis and organocatalysis. Photon-induced enamine oxidation provides an activated β-enaminyl radical intermediate, which readily combines with a wide range of Michael acceptors to produce β-alkyl aldehydes in a highly efficient manner. Furthermore, this redox-neutral, atom-economical C–H functionalization protocol can be achieved both inter- and intramolecularly. Mechanistic studies by various spectroscopic methods suggest that a reductive quenching pathway is operable.
Bringing individuals back in: the effects of career experience on new firm founding

Because of methodological and theoretical obstacles, research on organizational foundings has largely focused on societal and population-level explanations. This paper takes the view that understanding firm foundings also requires linking to individual-level processes. We suggest that careers are an important mechanism linking individual-level processes to firm foundings. The firm-founding experience of potential founders impacts organizational foundings by influencing expectations of the liability of newness. We test our explanation on the set of inventions patented by the Massachusetts Institute of Technology over the period 1980--1996 by examining the effect of inventors' career experiences on the likelihood that an invention will be commercialized through the founding of a new organization. Copyright 2003, Oxford University Press.
Lack of response of an open-habitat ungulate to the presence of predator urine

La respuesta conductual de ungulados a la presencia de olores asociados a depredadores ha recibido algo de atencion, pero aun se sabe poco sobre cuan predominantemente los ungulados de habitat abiertos reaccionan a la presencia de olores de depredadores. Examinamos las respuestas conductuales del guanaco, Lama guanicoe, cuando estos animales estaban expuestos a orina de varios depredadores. Los guanacos solo reaccionaron a la presencia de la orina del puma en uno de los ensayos. La ausencia de respuesta registrada podria indicar que los guanacos utilizan mas la vision que el olfato para detectar a sus depredadores
Static hole in a critical antiferromagnet: field-theoretic renormalization group

We consider the quantum field theory of a single, immobile, spin S hole coupled to a two-dimensional antiferromagnet at a bulk quantum critical point between phases with and without magnetic long-range order. We present an alternative derivation of its two-loop β function; the results agree completely with earlier work [Phys. Rev. B 61 (2000) 15152], and also determine a new anomalous dimension of the hole creation operator.
Response of slightly damped gyroscopic systems

Abstract A second-order perturbation theory is developed for the response of slightly damped gyroscopic systems. The solution is based on the eigensolution for undamped gyroscopic systems and is expressed in terms of real quantities alone.
Normal state magnetism of the high Tc cuprate superconductors

Abstract Magnetic measurements of various types have played an essential role in establishing the novel normal state characteristics of high transition temperature (Tc) superconductors with Tc > 23 K. Among these materials, the highest Tc's (⩽ 125 K) are exhibited by the layered cuprates. In this paper, the normal state magnetic susceptibilities of the cuprates are reviewed and interpreted in the context of magnetic neutron scattering and other magnetic measurements, using the La2−xMxCuO4-type and YBa2Cu3O6+x-type materials as prototypical examples. The evolution of the magnetism upon doping the insulating antiferromagnetic “parent” compounds with x = 0 to form the high temperature superconductors is described. A recurrent property which differentiates these materials from conventional superconductors is the existence of strong antiferromagnetic correlations in the metallic state on the same sublattice of the structure in which the itinerant carriers reside.
Regioselective arylation of 2'-deoxyribonucleosides on amido or imino sites by copper(II)-mediated direct coupling with arylboronic acids

Abstract N 1 -Aryl derivatives of 2′-deoxyguanosine (dG) were synthesized by copper(II)-mediated coupling of dG with arylboronic acids. Analogous aryl derivatives of 2′-deoxyinosine (dIn), 2′-deoxyuridine (dU), thymidine (T), 2′-deoxyadenosine (dA), and 2′-deoxycytidine (dC) were also conveniently synthesized by this method. Arylation took place preferentially on the amido functions in dG and dIn and the imino functions in dU or T. Remarkably, the nucleosides themselves served as internal ligands as well as reactants.
Late-time Kerr tails: generic and non-generic initial data sets, 'up' modes, and superposition

Three interrelated questions concerning Kerr spacetime late-time scalar-field tails are considered numerically, specifically the evolutions of generic and non-generic initial data sets, the excitation of 'up' modes, and the resolution of an apparent paradox related to the superposition principle. We propose to generalize the Barack?Ori formula for the decay rate of any tail multipole given a generic initial data set, to the contribution of any initial multipole mode. Our proposal leads to a much simpler expression for the late-time power-law index. Specifically, we propose that the late-time decay rate of a kinematically allowed Y?m spherical harmonic multipole moment because of an initial multipole is independent of the azimuthal number m and is given by t?n, where n = ?' + ? + 1 for ? < ?' and n = ?' + ? + 3 for ? ? ?'. We also show explicitly that the angular symmetry group of a multipole does not determine its late-time decay rate.
Classical Lagrangian model of the Pauli principle

Abstract A classical Lagrangian model of the Pauli potential is introduced. It is shown that the kinematic kinetic energy ( Σ 1 2 mv 2 )in the model approximately reproduces the energy of a free Fermi gas at low temperatures and at densities relevant in nuclearcollisions with moderate beam energies. Differences between canonical and kinematic quantities are pointed out. The Paulipotential can be used in transport simulations.
The Increase in the Primary Cosmic-Ray Intensity at High Latitudes, and the Non-Existence of a Detectable Permanent Solar Magnetic Field

The primary cosmic-ray intensity at Churchill, Manitoba (geomagnetic latitude 69\ifmmode^\circ\else\textdegree\fi{} N) has been compared directly with that at Swarthmore, Pennsylvania (geomagnetic latitude 52\ifmmode^\circ\else\textdegree\fi{} N). The measurements, obtained with identical vertical quadruplecoincidence counter trains, have revealed an increase at the more northern station caused by the presence in the primary radiation of particles having energies below that which would have been permitted had the sun's magnetic field been effective to the extent previously assumed. The ratio of intensities is $\frac{{I}_{T}(0,69\ifmmode^\circ\else\textdegree\fi{})}{{I}_{T}(0,52\ifmmode^\circ\else\textdegree\fi{})}=1.46$. Intensity vs. altitude curves were obtained with several different thicknesses of absorber interposed in the counter trains.
Attosecond photoelectron spectroscopy of metal surfaces.

Recent attosecond-streaking spectroscopy experiments [A.L. Cavalieri et al., Nature (London) 449, 1029 (2007)] using copropagating extreme ultraviolet (XUV) and infrared (IR) pulses of variable relative delay have measured a delay of approximately 100 attoseconds between photoelectrons emitted by a single XUV photon from localized core states and delocalized conduction-band states of a tungsten surface. We analyze the underlying XUV-photoemission–IR-streaking mechanism by combining a perturbative description of the XUV-photoemission process and the subsequent nonperturbative IR streaking of the photoelectrons. Our calculated time-resolved photoelectron spectra agree with the experiments of Cavalieri et al. and demonstrate that the observed temporal shift is caused by the interference of core-level photoelectrons that originate in different layers of the solid.
Antiferromagnetic resonance linewidth in MnF2 near the transition temperature

Abstract The antiferromagnetic resonance (AFMR) linewidth of MnF2 was studied near the Neel temperature. In the presence of an applied magnetic field, the linewidth diverges approximately as |T−T N | − 5 6 . In the absence of an applied field, the line-width is larger and diverges approximately as |T−T N | − 4 3 . The linewidth is independent of the direction of the magnetic field and is the same for both branches of the AFMR spectrum. Though qualitative attempts to explain the temperature dependence both in the presence and absence of an applied magnetic field were made, a detailed theoretical explanation is still lacking. The independence of the linewidth on applied magnetic field direction and on AFMR mode are what we expect intuitively, although work by Mori and Kawasaki suggests that the linewidths for the two branches of the AFMR spectrum ought to be different. Above TN electron paramagnetic resonance (EPR) in MnF2 was observed. For H parallel to c, at temperatures near TN, the linewidth increases approximately as |T−T N | − 3 8 . A smaller increase occurs for H perpendicular to c. The EPR data are discussed relative to the work of Heller and Benedek and of Moriya.
Enhanced lithium ion conductivity in lithium lanthanum titanate solid electrolyte nanowires prepared by electrospinning

Abstract Solid electrolytes have great potential to address the safety issues of Li-ion batteries, but better synthesis methods are still required for ceramics such as lithium lanthanum titanate (LLTO) since current techniques require high-temperature calcination for long times. Here we report a new approach that utilizes electrospinning to prepare phase-pure polycrystalline LLTO nanowires with well-crystallized tetragonal structure after only 3 h calcination at 1000 °C. Pellets prepared from the electrospun LLTO nanowires had higher density, less void space, and higher Li + conductivity compared to those comprised of LLTO prepared with conventional sol–gel methods. This work demonstrates the potential that electrospinning can provide towards improving the properties of sol–gel derived ceramics.
Scientific progress on the Fenton Hill HDR project since 1983

Abstract The modern HDR concept originated at the Los Alamos National Laboratory and was first demonstrated at Fenton Hill, New Mexico (USA). Experience gained during the development of the deeper HDR reservoir at Fenton Hill clearly showed that HDR reservoirs are formed by opening pre-existing, but sealed, multiply-connected joint sets. Subsequent flow testing indicated that sustained operation of HDR systems under steady-state conditions is feasible. The most significant remaining HDR issues are related to economics and locational flexibility. Additional field test sites are needed to advance the understanding of HDR technology so that the vast potential of this resource can be economically realized around the world.
A Direct Way to Find the Right Key of a Semistandard Young Tableau

The right key of a semistandard Young tableau is a tool used to find Demazure characters for $${sl_n(\mathbb{C})}$$ . This paper gives methods to obtain the right and left keys by inspection of the semistandard Young tableau.
Efficient generation of shared RSA keys

We describe efficient techniques for a number of parties to jointly generate an RSA key. At the end of the protocol an RSA modulus N = pq is publicly known. None of the parties know the factorization of N. In addition a public encryption exponent is publicly known and each party holds a share of the private exponent that enables threshold decryption. Our protocols are efficient in computation and communication. All results are presented in the honest but curious scenario (passive adversary).
Effect of blood group determinants on binding of human salivary mucous glycoproteins to influenza virus.

Abstract We have demonstrated that the inhibitor of influenza B virus hemagglutination in human saliva is inactivated by neuraminidase and is associated with the mucous glycoprotein fraction (blood group substance) of this secretion. Inhibitory activity of saliva was found to be roughly proportional to its sialic acid content ( r = 0.456). However, the minimal quantity of salivary sialic acid, neutral sugar, or blood group antigen required to inhibit virus hemagglutinatino was greater of secretors of A and B than for secretors of H and Le a blood group substances. Removal of terminal galactose from blood group B substance with α-galactosidase markedly decreased blod group B activity but increased blood group H and virus hemagglutination inhibitory activities of this glycoprotein. These data suggest that terminal α-linked galactose and, probably, N -acetyl-galactosamine interfere with access of influenza virus to binding sites onn oligosaccharide chains of the mucous glycoprotein
REGULARITY AND RESOLUTIONS FOR MULTIGRADED MODULES

This paper is concerned with the relationships between two concepts, vanishing of cohomology groups and the structure of free resolutions. In particular, we study the connection between vanishing theorems for the local cohomology of multigraded modules and the structure of their free multigraded resolutions.
A comprehensive method for solving finite-state semi-Markov processes

Semi–Markov processes (SMPs) provide a rich framework for many real–world problems. However, owing to difficulty in implementing practical solutions they are rarely used with their full capability. The theory of SMPs is quite mature but was mainly developed at a time when computational resources were not widely available. With the exception of some of the simplest cases, solutions to SMPs are inherently numerical, and SMPs have been underutilised by practitioners because of difficulty in implementing the theory in applications. This paper demonstrates the theory and computational methods needed to implement SMP models in practical settings. Methods are illustrated with an application modelling the movement of coronary patients in a hospital. Our aim is to allow practitioners to use richer SMP models without being burdened with the rigorous mathematical theory.
Understanding and exploiting C–H bond activation

The selective transformation of ubiquitous but inert C–H bonds to other functional groups has far-reaching practical implications, ranging from more efficient strategies for fine chemical synthesis to the replacement of current petrochemical feedstocks by less expensive and more readily available alkanes. The past twenty years have seen many examples of C–H bond activation at transition-metal centres, often under remarkably mild conditions and with high selectivity. Although profitable practical applications have not yet been developed, our understanding of how these organometallic reactions occur, and what their inherent advantages and limitations for practical alkane conversion are, has progressed considerably. In fact, the recent development of promising catalytic systems highlights the potential of organometallic chemistry for useful C–H bond activation strategies that will ultimately allow us to exploit Earth's alkane resources more efficiently and cleanly.
Numerical Solution of the Azimuthal-Invariant Thin-Layer Navier-Stokes Equations

NUMERICAL solutions have been obtained for a twodimensional azimuthal- (or circumferentially) invariant form of the thin-layer Navier-Stokes equations. The governing equations which have been developed are generalized over the usual two-dimensional and axisymmetric formulation by allowing nonzero velocity components in the invariant direction. The equation formulation along with the solution method is described, and results for spinning and nonspinning bodies are presented. Contents The three-dimensional flow field equations are frequently simplified for flowfields which are invariant in one coordinate direction. In the usual axisymmetric approximation, the azimuthal velocity is assumed to be zero, and the momentum equation in that direction can be eliminated. Thus, only four equations are required to be solved for four unknowns. However, for a variety of interesting flowfields, the velocity component in the invariant direction (here taken as TJ) is not zero although the governing equations are still twodimensional. Examples include viscous flow about an infinitely swept wing, the viscous flow about a spinning axisymmetric body at 0-deg angle of attack, and axisymmetric swirl flows. Each of these flows can be solved as a twodimensional problem although all three momentum equations have to be retained, and source terms replace the derivative of the flux terms in the rj-direction. Azimuthal-invariant equations are obtained from the threedimensional equations1 by making use of two restrictions: 1) all body geometries are of axisymmetric types and 2) the state variables and the contravariant velocities do not vary in the azimuthal direction. Here, TJ is used for the azimuthal coordinate, and the terms azimuthal and rj-invariant will be used interchangeably. A sketch of a typical axisymmetric body is shown in Fig. la. In order to determine the circumferential variation of typical flow and geometric parameters, we first establish correspondence between the
Plane harmonic waves in an infinite piezoelectric plate with dissipation

In a previous paper, the three-dimensional equations of linear piezoelectricity with quasielectrostatic approximation were extended to include losses attributed to the mechanical damping in solid and the resistance in current conduction. These equations were used to investigate the plane wave propagation in an unbounded solid and forced thickness vibration of an infinite piezoelectric plate. In the present paper, these equations are used to obtain solutions of plane harmonic wave of arbitrary direction in an infinite and dissipative piezoelectric plate with general crystal symmetry. Dispersion curves are computed and plotted for real frequencies and complex wave numbers. All frequency branches are complex for dissipative plate. There are no longer any pure real or pure imaginary or complex conjugate frequency branches as those existing for nondissipative plates. Effects of dissipation on the wave propagation are examined in detail for AT-cut of quartz as well as barium titanate ceramic plate.
Does De Jure Judicial Independence Really Matter

AbstractThe relationship between de jure and de facto judicial independence is much debated in the literature on judicial politics. Some studies find no relationship between the formal rules governing the structure of the judiciary and de facto judicial independence, while others find a tight correlation. This article sets out to reassess the relationship between de jure and de facto judicial independence using a new theory and an expanded data set. De jure institutional protections, we argue, do not work in isolation but work conjunctively, so that particular combinations of protections are more likely to be effective than others. We find that rules governing the selection and removal of judges are the only de jure protections that actually enhance judicial independence in practice and that they work conjunctively. This effect is strongest in authoritarian regimes and in contexts with checks on executive authority.
Soliton gauge states and T-duality of closed bosonic string compatified on torus

We study soliton gauge states in the spectrum of bosonic string compatified on torus. The enhenced Kac-Moody gauge symmetry, and thus T-duality, is shown to be related to the existence of these soliton gauge states in some moduli points.
Bubbles or Convenience Yields? A Theoretical Explanation with Evidence from Technology Company Equity Carve-Outs

Abstract This paper offers an alternative explanation for what is typically referred to as an asset pricing bubble. We develop a model that formalizes the Cochrane (2002) convenience yield theory of technology company stocks to explain why a rational agent would buy an “overpriced” security. Agents have a desire to trade but short-sale restrictions and other frictions limit their trading strategies and enable prices of two similar securities to be different. Thus, divergent prices for similar securities can be sustained in a rational expectations equilibrium. The paper also provides empirical support for the model using a sample of 1996–2000 equity carve-outs.
Remarks on generalized toric codes

This note presents some new information on how the minimum distance of the generalized toric code corresponding to a fixed set of integer lattice points S ? R 2 varies with the base field. The main results show that in some cases, over sufficiently large fields, the minimum distance of the code corresponding to a set S will be the same as that of the code corresponding to the convex hull conv ( S ) . In an example, we will also discuss a 49 , 12 , 28 generalized toric code over F 8 , better than any previously known code according to M. Grassl's online tables, as of December 2012.
The Remarkable High Pressure of the Local Leo Cold Cloud

Using the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope, we have obtained high-resolution ultraviolet spectra of the C I absorption toward two stars behind the Local Leo Cold Cloud (LLCC). At a distance ( Almost-Equal-To 20 pc) that places it well inside the Local Bubble, the LLCC is the nearest example of the coldest known (T Almost-Equal-To 20 K) diffuse interstellar clouds. The STIS measurements of the C I fine-structure excitation toward HD 85259 and HD 83023 indicate that the thermal gas pressure of the LLCC is much greater than that of the warm clouds in the Local Bubble. The mean LLCC pressure measured toward these two stars (60,000 cm{sup -3} K) implies an H I density of Almost-Equal-To 3000 cm{sup -3} and a cloud thickness of Almost-Equal-To 200 AU at the 20 K cloud temperature. Such a thin, cold, dense structure could arise at the collision interface between converging flows of warm gas. However, the measured LLCC pressure is appreciably higher than that expected in the colliding-cloud interpretation given the velocity and column density constraints on warm clouds in the HD 85259 and HD 83023 sightlines. Additional STIS measurements of the Zn II, Ni II,more » and Cr II column densities toward HD 85259 indicate that the LLCC has a modest 'warm cloud' dust depletion pattern consistent with its low dust-to-gas ratio determined from H I 21 cm and 100 {mu}m observations. In support of the inferred sheet-like geometry for the LLCC, a multi-epoch comparison of the Na I absorption toward a high-proper-motion background star reveals a 40% column density variation indicative of LLCC Na I structure on a scale of Almost-Equal-To 50 AU.« less
The use of virtual microscopy and a wiki in pathology education: Tracking student use, involvement, and response

Background: The pathology laboratory course at the New York College of Podiatric Medicine involves the use of Virtual Microscopy. The students can scan the whole slide, section by section, and zoom in or out. Methods: Using the advantages of digital pathology, the students can, in addition, access the slide collections from other medical schools and put up normal histology (control) slides side-by-side with the pathology. They can cut and paste and preserve the region of interest that they find. They can edit and annotate their slides. A wiki was created ( http://pathlab2014.wikifoundry.com ) for the Class of 2014. The students saved, edited and uploaded their slides. In the wiki format, other students could comment, further edit, and even delete the slides. Results: The students studied Basic Mechanisms and System Pathology. During this time, they saved, edited, shared, and uploaded their slides to the wiki. These were available in one full presentation and were also grouped into 16 albums. They were available to all. Student access was followed by Google analytics. At the end of the course, a questionnaire was distributed, assessing their impression of the wiki format and soliciting strengths and weaknesses. Conclusions: The use of a wiki has a number of important advantages in pathology education. It trains the students in the more sophisticated skills that they will use as professional pathologists or as clinicians: (1) Telepathology-it enables them to share slides and discuss observations. (2) Archiving and retrieval - It models the challenge faced by hospitals, diagnostic labs and physicians in maintaining a collection of slides in a form that is easily accessible. (3) Image analysis-familiarity with the wiki format allows them to jump easily to capturing and storing images found in the literature or in a pathologist's report. Experience with the use of a wiki in pathology education has been quite satisfactory from both the faculty and the student's point of view.
SOLID-STATE CONFORMATIONS OF FIVE MEMBERED RING PHOSPHORUS HETEROCYCLES: X-RAY CRYSTAL STRUCTURES OF THREE 1,3,2-OXAZAPHOSPHOLANES

Abstract Single-crystal X-ray structural determinations have been made on (2S,4R,5R)-2-phenoxy-2-oxo-3,4- dimethyl-5-phenyl-l,3,2-oxazaphospholane, 1; (2S,4R,5R)-2-(dimethylamino)-2-oxo-3,4-dimethyl-5- phenyl-l,3,2-oxazaphospholane, 2; and (2S,4R,5S)-2-phenoxy-2-oxo-3,4-dimethyl-5-phenyl-l,3,2- oxazaphospholane, 3. The solid-state conformations adopted by these materials are P(2) half-chair, envelope C(4), and P(2) half-chair. respectively.
New chiral 1,1′-bis(phospholano)ferrocene ligands for asymmetric catalysis

Abstract The synthesis of two new 1,1′-bis(phospholano)ferrocene ligands are described. Preliminary catalytic studies showed that enantioselectivities as high as 83% ee could be achieved in the hydrogenation of several model olefin, ketone, and hydrazone substrates.
A new synthesis of (Z)-coniferyl alcohol, and characterization of its derived synthetic lignin

Abstract The (Z)-monolignols (hydroxycinnamyl alcohols) are found along with their predominant (E)-isomers in a number of plants. Their role in lignification is unknown. A new synthetic route to (Z)-coniferyl alcohol has been developed via Still and Gennari's modification of the Horner-Emmons olefination to produce (Z)-unsaturated esters. Although previous studies have shown that (Z)-coniferyl alcohol will polymerize by single-electron (radical) processes to produce synthetic lignins, the stereochemistry of units in the resulting structure had not been addressed. NMR analysis of a synthetic lignin from (Z)-coniferyl a alcohol indicates that unsaturated sidechains in the resulting lignin retain their (Z)-geometry. Other structures are altered in their relative proportions but retain the same stereochemistry. Assignment of structures in these synthetic lignins provides the necessary database for more careful examination of real plant lignins.
String theoretic bounds on Lorentz violating warped compactification

We consider warped compactifications that solve the 10 dimensional supergravity equations of motion at a point, stabilize the position of a D3-brane world, and admit a warp factor that violates Lorentz invariance along the brane. This gives a string embedding of ``asymmetrically warped'' models which we use to calculate stringy (α') corrections to standard model dispersion relations, paying attention to the maximum speeds for different particles. We find, from the dispersion relations, limits on gravitational Lorentz violation in these models, improving on current limits on the speed of graviton propagation, including those derived from field theoretic loops. We comment on the viability of models that use asymmetric warping for self-tuning of the brane cosmological constant.
Ecto-5'-nucleotidase (CD73)-mediated extracellular adenosine production plays a critical role in hepatic fibrosis.

In previous studies, we have demonstrated that adenosine and its receptors play a role in hepatic fibrosis. Here, we review evidence that toxin-induced increases in hepatic adenosine concentrations are generated from adenine nucleotides by the action of ecto-5′nucleotidase and thus that adenosine-mediated, toxin-induced hepatic fibrosis depends on extracellular conversion of adenine nucleotides to adenosine.
Computational Geometry Column 29

Past accomplishments of Computational Geometry are reviewed and future directions adumbrated.
Formation Flying Control of Multiple Spacecraft via Graphs, Matrix Inequalities, and Switching

Ideas from elementary graph theory and linear matrix inequalities are combined with logic-based switching to shed light on the various control strategies which are feasible in the leader-following framework for the formation flying of multiple spacecraft.
CONTRIBUTIONS OF THE SCHOOL NURSE IN A SCHOOL DENTAL PROGRAM

The school nurse as the pivot about which the dental program is organized and functions': A realistic approach to the school dental health program faces us with the fact that no matter how many people in and outside the school actually participate in the program, the school nurse is primarily the one to whom every one looks, in order to start things moving and to keep them moving. Few schools have a full-time dentist, which means that the school dentist relies heavily upon the nurse to interpret his findings and help people to secure the necessary dental care. While the nurse is the chief responsible agent to see that the dental program is carried on, she cannot do this without the cooperation of the administrator and the entire teaching staff. A successful dental health program is the result of good team work between all concerned, with the nurse at the helm sending out the necessary notices to parents, fully informing teachers and administrators of the dental defects noted by the dentist, and interpreting his findings in terms of what progress they may or may not reveal. A showing by percentages of the present situation and comparing it with past records, is a helpful means of interesting pupils
Photoluminescence detected doublet structure in the integer and fractional quantum Hall regime

We present here the results of polarized magneto-photoluminescence measurements on a high mobility single-heterojunction. The presence of a doublet structure over a large magnetic field range (2>v>l/6) is interpreted as possible evidence for the existence of a magneto-roton minima of the charged density waves. This is understood as an indication of strong electronic correlation even in the case of the IQHE limit.
Evolution of Type 2 Vaccine Derived Poliovirus Lineages. Evidence for Codon-Specific Positive Selection at Three Distinct Locations on Capsid Wall

Partial sequences of 110 type 2 poliovirus strains isolated from sewage in Slovakia in 2003-2005, and most probably originating from a single dose of oral poliovirus vaccine, were subjected to a detailed genetic analysis. Evolutionary patterns of these vaccine derived poliovirus strains (SVK-aVDPV2) were compared to those of type 1 and type 3 wild poliovirus (WPV) lineages considered to have a single seed strain origin, respectively. The 102 unique SVK-aVDPV VP1 sequences were monophyletic differing from that of the most likely parental poliovirus type 2/Sabin (PV2 Sabin) by 12.5-15.6%. Judging from this difference and from the rate of accumulation of synonymous transversions during the 22 month observation period, the relevant oral poliovirus vaccine dose had been administered to an unknown recipient more than 12 years earlier. The patterns of nucleotide substitution during the observation period differed from those found in the studied lineages of WPV1 or 3, including a lower transition/transversion (Ts/Tv) bias and strikingly lower Ts/Tv rate ratios at the 2(nd) codon position for both purines and pyrimidines. A relatively low preference of transitions at the 2(nd) codon position was also found in the large set of VP1 sequences of Nigerian circulating (c)VDPV2, as well as in the smaller sets from the Hispaniola cVDPV1 and Egypt cVDPV2 outbreaks, and among aVDPV1and aVDPV2 strains recently isolated from sewage in Finland. Codon-wise analysis of synonymous versus non-synonymous substitution rates in the VP1 sequences suggested that in five codons, those coding for amino acids at sites 24, 144, 147, 221 and 222, there may have been positive selection during the observation period. We conclude that pattern of poliovirus VP1 evolution in prolonged infection may differ from that found in WPV epidemics. Further studies on sufficiently large independent datasets are needed to confirm this suggestion and to reveal its potential significance.
Assessment of coronary plaque collagen with polarization sensitive optical coherence tomography (PS-OCT)

Abstract Introduction Current evidence indicates that most plaques classified as vulnerable or ruptured plaque do not lead to unstable angina or myocardial infarction. Improved methods are needed to risk stratify plaques to identify those which lead to most acute coronary syndromes. Collagen depletion in the intima overlying lipid collections appears to be a critical component of unstable plaques. In this study, we use polarization sensitive optical coherence tomography (PS-OCT) for the assessment of coronary plaque collagen. Collagen is birefringent, meaning that different polarization states travel through it at different velocities. Methods and results Changes in PS-OCT images are a measure of tissue birefringence. Twenty-two coronary artery segments were imaged with PS-OCT and analyzed by picrosirius staining (a measure of collagen intensity and fiber size) and trichrome blue. The regression plot between PS-OCT changes and measured collagen yielded a correlation coefficient value of 0.475 ( p Conclusion The capability of PS-OCT to assess plaque collagen content, in addition to its ability to generate high resolution structural assessments, make it a potentially powerful technology for identifying high risk plaques.
Efficient chemical synthesis of methyl β-glycosides of β-(1→6)-linked d-galacto-oligosaccharides by a stepwise and a blockwise approach

Bromoacetylation of methyl 2,3,4-tri-O-benzoyl-beta-D-galactopyranoside (1) followed by cleavage of the methoxyl group from the resulting 6-O-bromoacetyl derivative 2 with 1,1-dichloromethyl methyl ether gave 2,3,4-tri-O-benzoyl-6-O-bromoacetyl-alpha-D-galactopyranosyl chloride (3). Reaction of 3 with 1, promoted by silver trifluoromethanesulfonate, afforded methyl O-(2,3,4-tri-O-benzoyl-6-O-bromoacetyl-beta-D-galactopyranosyl)-(1----6) -2,3,4-tri-O-benzoyl-beta-D-galactopyranoside (12), bearing at O-6 of its non-reducing end-group the selectively removable bromoacetyl group. This was O-debromoacetylated and the disaccharide nucleophile 15 formed was again treated with 3, to give the analogous trisaccharide 18. This sequence of reactions was repeated to afford the analogous tetrasaccharide 20, showing the feasibility of stepwise construction of the title oligosaccharides. Similar reactions of 3 with 1,2,3,4-tetra-O-benzoyl-alpha- (7) and beta-D-galactopyranose (5) gave, respectively, O-(2,3,4-tri-O-benzoyl-6-O-bromoacetyl-beta-D-galactopyranosyl)-(1----6) -1,2,3,4-tetra-O-benzoyl-alpha- (14) and beta-D-galactopyranose (13). These could be separately converted into the same glycosyl halide, namely, alpha-(2,3,4-tri-O-benzoyl-6-O-bromoacetyl-beta-D-galactopyranosyl)-(1-- --6)-2,3,4-tri-O-benzoyl-alpha-D-galactopyranosyl chloride (16), by cleavage with 1,1-dichloromethyl methyl ether. The chloride 16 was treated with tri- and tetra-saccharide nucleophiles analogous to 15 to give, respectively, the corresponding pentasaccharide 23 and the hexasaccharide 25, demonstrating the possibility of the blockwise construction of higher beta-(1----6)-linked D-galacto-oligosaccharides. The disaccharide 12 was also obtained by the reaction of 1,2,3,4-tetra-O-benzoyl-6-O-bromoacetyl-beta-D-galactopryanose (6) with 1 in the presence of trimethylsilyl trifluoromethane-sulfonate. Similarly, the trisaccharide 18 and the tetrasaccharide 20 were obtained by the treatment of 13, respectively, with 1 and 15, showing that, as with their 1-O-acetyl counterparts, beta-1-benzoates of saccharides bearing at O-2 a group capable of neighboring-group participation can act under these conditions as glycosyl donors. Crystalline methyl beta-glycosides of (1----6)-beta-D-galacto-tetraose (22), -pentaose (24) and -hexaose (27) have been obtained for the first time, by deacylation (Zemplen) of their fully protected precursors.
Mercury dynamics in sulfide-rich sediments: Geochemical influence on contaminant mobilization within the Penobscot River estuary, Maine, USA

Abstract Research concerning the fate and biogeochemical cycling of mercury (Hg) within coastal ecosystems has suggested that microbially mediated diagenetic processes control Hg mobilization and that ligands with strong affinity for Hg, such as dissolved inorganic sulfide (S(-II)) and dissolved organic matter (DOM), control Hg partitioning between the dissolved and particulate phases. We have studied total Hg cycling in the sediments of the Penobscot River estuary using a combination of equilibrium porewater samplers and kinetic modeling. The Penobscot estuary has been subject to Hg contamination from multiple industries including a recently closed chlor-alkali production facility. The Hg concentration within the estuary surface sediments ranges from 1.25 to 27.5 nmol Hg g−1 sediment and displays an association with sediment organic matter and a concentration maximum within 3 cm of the sediment–water interface (SWI). Porewater profiles for the Penobscot estuary are divisible into three kinetically discrete intervals with respect to Hg dynamics. Beginning at depth in the sediment and moving upward toward the SWI we have defined: (1) a zone of net Hg solubilization at depth, with a zero-order net Hg production rate ( R net Hg T ) = 3.7 – 5.2 × 10 - 20 mol cm - 3 s - 1 , (2) a zone of net Hg consumption within the zone dominated by FeS(s) precipitation with R net Hg T = - 0.75 to - 1.4 × 10 - 20 mol cm - 3 s - 1 , and (3) a zone of net diffusive transfer within the vicinity of the SWI. Zone 1 is characterized by dissolved S(-II) concentrations ranging from 400 to 500 μM. Equilibrium modeling in this zone suggests that inorganic S(-II) plays the dominant role in both mobilization of sediment-bound Hg and complexation of dissolved Hg. In zone 2, FeS(s) precipitation occurs concomitant with Hg consumption. Net transfer within zone 3 is consistent with the potential for ligand-mediated Hg efflux across the SWI. S(-II)-mediated Hg mobilization at depth in Penobscot estuary sediments suggests a broadening of the depth interval over which biogeochemical Hg cycling must be examined. Our results also show that, while estuary sediments act as a net sink for particulate Hg inputs, they may also function for a considerable time interval as a source of dissolved Hg.
A TEMPERATURE AND ABUNDANCE RETRIEVAL METHOD FOR EXOPLANET ATMOSPHERES

We present a new method to retrieve molecular abundances and temperature profiles from exoplanet atmosphere photometry and spectroscopy. We run millions of one-dimensional (1D) atmosphere models in order to cover the large range of allowed parameter space. In order to run such a large number of models, we have developed a parametric pressure–temperature (P–T) profile coupled with line-by-line radiative transfer, hydrostatic equilibrium, and energy balance, along with prescriptions for non-equilibrium molecular composition and energy redistribution. The major difference from traditional 1D radiative transfer models is the parametric P–T profile, which essentially means adopting energy balance only at the top of the atmosphere and not in each layer. We see the parametric P–T model as a parallel approach to the traditional exoplanet atmosphere models that rely on several free parameters to encompass unknown absorbers and energy redistribution. The parametric P–T profile captures the basic physical features of temperature structures in planetary atmospheres (including temperature inversions), and fits a wide range of published P–T profiles, including those of solar system planets. We apply our temperature and abundance retrieval method to the atmospheres of two transiting exoplanets, HD 189733b and HD 209458b, which have the best Spitzer and Hubble Space Telescope data available. For HD 189733b, we find efficient day–night redistribution of energy in the atmosphere, and molecular abundance constraints confirming the presence of H2O, CO, CH4, and CO2. For HD 209458b, we confirm and constrain the dayside thermal inversion in an average 1D temperature profile. We also report independent detections of H2O, CO, CH4, and CO2 on the dayside of HD 209458b, based on six-channel Spitzer photometry. We report constraints for HD 189733b due to individual data sets separately; a few key observations are variable in different data sets at similar wavelengths. Moreover, a noticeably strong CO2 absorption in one data set is significantly weaker in another. We must, therefore, acknowledge the strong possibility that the atmosphere is variable, both in its energy redistribution state and in the chemical abundances.
DEACON: direct English access and control

The extensive syntactic ambiguity inherent in natural language has been convincingly shown by such systems as the Harvard syntactic analyzer. Furthermore, no semantic techniques are in prospect for satisfactory resolution of this ambiguity by computer. In contrast, well-developed semantic techniques exist for formal languages.
Evidence for shared cognitive processing of pitch in music and language.

Language and music epitomize the complex representational and computational capacities of the human mind. Strikingly similar in their structural and expressive features, a longstanding question is whether the perceptual and cognitive mechanisms underlying these abilities are shared or distinct – either from each other or from other mental processes. One prominent feature shared between language and music is signal encoding using pitch, conveying pragmatics and semantics in language and melody in music. We investigated how pitch processing is shared between language and music by measuring consistency in individual differences in pitch perception across language, music, and three control conditions intended to assess basic sensory and domain-general cognitive processes. Individuals’ pitch perception abilities in language and music were most strongly related, even after accounting for performance in all control conditions. These results provide behavioral evidence, based on patterns of individual differences, that is consistent with the hypothesis that cognitive mechanisms for pitch processing may be shared between language and music.
[3+2] Cycloaddition reactions of diethyl (E)-2-fluoromaleate

Abstract Diethyl E -2-fluoromaleate has been prepared in a pure state in 89% yield by a Horner–Wadsworth–Emmons Wittig procedure. The E configuration was determined by NMR spectroscopy. Diethyl E-2-fluoromaleate undergoes [3+2] cycloadditions with a series of aromatic α-iminoesters and aromatic nitrones. The yields of purified cyclic products ranged from 65 to 80%.
Exercising Market Power in Proprietary Aftermarkets

Over 20 recent antitrust cases have turned on whether competition in complex durable-equipment markets prevents manufacturers from exercising market power over proprietary aftermarket products and services. We show that the price in the aftermarket will exceed marginal cost despite competition in the equipment market. Absent perfectly contingent long-term contracts, firms will balance the advantages of marginal-cost pricing to future generations of consumers against the payoff from monopoly pricing for current, locked-in equipment owners. The result holds for undifferentiated Bertrand competition, differentiated duopoly, and monopoly equipment markets. We also examine the effects of market growth and equipment durability.
Coupled Interfacial Energy and Temperature Effects on Size-Dependent Yield Strength and Strain Hardening of Small Metallic Volumes

Plasticity in heterogeneous metallic materials with small volumes is governed by the interactions of dislocations at interfaces. In particular, interfaces of a material confined in a small volume can strongly affect the mechanical properties of micro and nanosystems. In this paper, the framework of higher-order strain gradient plasticity theory with interfacial energy effect is used to investigate the coupling of interfacial energy with temperature and how it affects the initial yield strength (i.e., onset of plasticity) and the strain hardening rates of confined small metallic volumes. It is postulated that the interfacial energy decreases as temperature increases such that size effect decreases as temperature increases. As an application, the size effect of thermal loading of a film-substrate system is investigated. It is shown that the temperature at which the film starts to yield plastically is size-dependent, which is attributed to the size-dependent yield strength. Furthermore, the flow stress is more temperature sensitive as the size decreases.
Relay Subset Selection in Wireless Networks Using Partial Decode-and-Forward Transmission

This paper considers the problem of selecting a subset of nodes in a two-hop wireless network to act as relays in aiding the communication between the source-destination pair. Optimal relay subset selection with the objective of maximizing the overall throughput is a difficult problem that depends on multiple factors, including node locations, queue lengths, and power consumption. A partial decode-and-forward strategy is applied in this paper to improve the tractability of the relay selection problem and the performance of the overall network. Note that the number of relays that are selected ultimately determines the performance of the network. This paper benchmarks this performance by determining the net diversity that is achieved using the relays that are selected and the partial decode-and-forward strategy. This framework is subsequently used to further transform relay selection into a simpler relay placement problem, and two proximity-based approximation algorithms are developed to determine the appropriate set of relays to be selected in the network. Other selection strategies, such as random relay selection and a greedy algorithm that relies on channel state information, are also presented. This paper concludes by showing that the proposed proximity-based relay selection strategies yield near-optimal expected rates for a small number of selected relays.
Bismuth (III) Acetate: A New Catalyst for Preparation of Azlactones via the Erlenmeyer Synthesis

Abstract Bismuth(III) acetate catalyzes the synthesis of azlactones from aromatic aldehydes in moderate to good yields via the Erlenmeyer synthesis. The relatively low toxicity and low cost of bismuth(III) acetate make this procedure particularly attractive.