cssi/SciSciGPT-SciSciNet huggingface dataset:
Locally Addressable Tunnel Barriers within a Carbon Nanotube

We report the realization and characterization of independently controllable, fabricated tunnel barriers within a carbon nanotube. The nanotubes are mechanically bent or kinked using an atomic force microscope, and top gates are subsequently placed near each kink. Transport measurements indicate that the kinks form gate-controlled tunnel barriers and that gates placed away from the kinks have little or no effect on conductance. The overall conductance of the nanotube can be controlled by tuning the transmissions through the kinks.
Scaled Boolean algebras

Scaled Boolean algebras are a category of mathematical objects that arose from attempts to understand why the conventional rules of probability should hold when probabilities are construed, not as frequencies or proportions or the like, but rather as degrees of belief in uncertain propositions. This paper separates the study of these objects from that not entirely mathematical problem that motivated them. That motivating problem is explicated in the first section, and the application of scaled Boolean algebras to it is explained in the last section. The intermediate sections deal only with the mathematics. It is hoped that this isolation of the mathematics from the motivating problem makes the mathematics clearer.
The Urysohn universal metric space is homeomorphic to a Hilbert space

Abstract The Urysohn universal metric space U is characterized up to isometry by the following properties: (1) U is complete and separable; (2) U contains an isometric copy of every separable metric space; (3) every isometry between two finite subsets of U can be extended to an isometry of U onto itself. We show that U is homeomorphic to the Hilbert space l2 (or to the countable power of the real line).
Ground-based detections of thermal emission from CoRoT-1b and WASP-12b

We report a new detection of the H-band thermal emission of CoRoT-1b and two confirmation detections of the Ks-band thermal emission of WASP-12b at secondary eclipses. The H-band measurement of CoRoT-1b shows an eclipse depth of 0.145% ± 0.049% with a 3σ percentile between 0.033% and 0.235%. This depth is consistent with the previous conclusions that the planet has an isothermal region with inefficient heat transport from day side to night side, and has a dayside thermal inversion layer at high altitude. The two Ks-band detections of WASP-12b show a joint eclipse depth of 0.299% ± 0.065%. This result agrees with the measurement of Croll & collaborators, providing independent confirmation of their measurement. The repeatability of the WASP-12b measurements also validates our data analysis method. Our measurements, in addition to a number of previous results made with other telescopes, demonstrate that ground-based observations are becoming widely available for characterization of atmospheres of hot Jupiters.
Polarization modulated solitary waves in an optical fiber

Abstract A family of solitary waves is found which satisfy the coupled nonlinear Schrodinger equations governing optical pulse propagation in an elliptical core optical fiber. These are polarization modulated pulses which are bound states of two solitons which when decoupled have constant and uniform orthogonal linear polarizations. The formation of these bound states is possible only above a minimum energy threshold determined by the ellipticity of the fiber.
Syntheses of the Saturated Analogues of 4-Nitrophenol and 4-Nitroaniline

Abstract Two syntheses for 4-nitrocyclohexanol and 4-nitrocyclohexanamine are presented. Both conveniently start from commercially available 4-aminocyclohexanol.
The currency denomination of external European Union imports after European Union expansion

Abstract Using a multiple market model I examine the impact of euro expansion on the optimal currency denomination of external EU imports. Results suggest euro invoicing will increase more in the EU-expansion country than in the original EU. Exporting firms from dollar bloc countries (the U.S. or countries with fixed exchange rates with the dollar) are more likely to invoice in the euro if price discrimination is already optimal. Firms from outside the dollar bloc are more likely to use the euro when the original EU market is relatively large or transaction costs of exchanging the euro are relatively small.
Three-dimensional boundary conditions in supersonic flow

Abstract A theoretical analysis of the flow pattern at a solid surface in three-dimensional supersonic flow is presented. The purpose of the study is to develop the additional information necessary to overcome the nonuniqueness associated with the body tangency condition in three dimensions. The analysis is based on the fact that three-dimensional waves propagate locally exactly as they do in axisymmetric flow when viewed in the osculating plane to streamline. The supersonic flow over an infinite swept corner is examined by both the classical solution and the three-dimensional solution in the osculating plane; the results are shown to be identical. A simple numerical algorithm is proposed which accounts for the three wave surfaces that interact at a solid boundary.
SETI field tests with the MCSA 1.0 prototype and plans for radio astronomical observations

Abstract In order to conduct a systematic microwave search for extraterrestrial intelligence (SETI), NASA is planning to use an advanced multichannel spectrum analyzer (MCSA) capable of resolving the input bandwidth into at least 10 million narrowband channels. To verify the digital architecture that NASA is proposing to use to construct such an instrument, a 74000 channel prototype, the MCSA 1.0, has been built and deployed in the field. This paper discusses the results of the field tests, implications for other components of an automated SETI observing system, and plans to use the MCSA 1.0 to carry out some more traditional radio astronomy observations.
A TIME COMPARISON STUDY OF THE NEW YORK STATE SAFETY BELT USE LAW UTILIZING HOSPITAL ADMISSION AND POLICE ACCIDENT REPORT INFORMATION

New York state enacted the first safety belt use law in the United States in 1984. We evaluated the effects of the law by reviewing all hospital admissions from motor vehicle crashes in Monroe County, New York. We compared admissions for the 18 months prior to the effective date of the law with those for the 18 months after the law became effective. Police accident reports and hospital records were coupled and intensively reviewed. Motorcyclists, pedestrians, and bicyclists (bicycle collisions with motor vehicles) became controls for the study. Seat belt usage was determined from police and hospital record information. Analysis of the data revealed that safety belt use among patients hospitalized because of motor vehicle accidents increased from 11.2% before the law became effective to 53% after the law became effective. Hospital admissions decreased 11.9% among motor vehicle occupants and increased 2.6% among controls. The ISS decreased from 16.01 to 14.55 for motor vehicle occupants and increased from 14.77 to 15.11 among controls. Among subjects all injuries decreased except injuries of the spine and abdomen, which increased in the postlaw period.
Synthesis and evaluation of hexahydrochrysene and tetrahydrobenzofluorene ligands for the estrogen receptor.

Abstract To prepare novel estrogen receptor (ER) ligands, we have developed a facile approach to substituted hexahydrochrysene and tetrahydrobenzo[ a ]fluorene systems. Substituents, including basic side chains, were added to these systems, and their binding affinity to ERα and ERβ, and in some cases their transcriptional activity were evaluated.
OPTIMIZATION OF SOLID ROCKET MOTOR IGNITER PERFORMANCE REQUIREMENTS

A numerical technique is presented for optimizing a set of solid rocket motor (SRM) ignition control variables to achieve a specific requirement or set of requirements to be used in preliminary design of an SRM igniter. The mathematical model of the igniter transients uses a simplified ignition simulation routine to calculate igniter and SRM performance. The object function to be optimized (minimized) is typically the summation of The absolute values of the differences between the desired and computed thrust values of the SRM at specified times during ignition. Constraints are imposed in the form of limiting values of igniter characteristics, flame-spreading speeds and/or maximum rate of pressure rise in the SRM. Optimization is obtained using a direct pattern search technique to determine the required values of the controlling variables. Examples are presented which illustrate the ability of the technique to meet practical design requirements. Computational results are shown to be consistent with the sta...
X-Ray Spectral Properties of Low-Mass X-Ray Binaries in Nearby Galaxies

We have investigated the X-ray spectral properties of a collection of low-mass X-ray binaries (LMXBs) within a sample of 15 nearby early-type galaxies using proprietary and archival data from the Chandra X-Ray Observatory. We find that the spectrum of the sum of the sources in a given galaxy is remarkably similar from galaxy to galaxy when only sources with X-ray luminosities less than 1039 ergs s-1 (0.3-10 keV) are considered. Fitting these lower luminosity sources in all galaxies simultaneously with a power-law model led to a best-fit power-law exponent of Γ = 1.56 ± 0.02 (90% confidence), and using a thermal bremsstrahlung model yielded kTbrem = 7.3 ± 0.3 keV. This is the tightest constraint to date on the spectral properties of LMXBs in external galaxies. The spectral properties of the LMXBs do not vary with galactic radius out to three effective radii. There is also no apparent difference between the spectral properties of LMXBs that reside within globular clusters and those that do not. We demonstrate how the uniformity of the spectral properties of LMXBs can lead to more accurate determinations of the temperature and metallicity of the hot gas in galaxies that have comparable amounts of X-ray emission from hot gas and LMXBs. Although few in number in any given galaxy, sources with luminosities of (1-2) × 1039 ergs s-1 are present in 10 of the galaxies. The spectra of these luminous sources are softer than the spectra of the rest of the sources and are consistent with the spectra of Galactic black hole X-ray binary candidates when they are in their very high state. The spatial distribution of these sources is much flatter than the optical light distribution, suggesting that a significant portion of them must reside within globular clusters. The simplest explanation of these sources is that they are ~10-15 M☉ black holes accreting near their Eddington limit. The spectra of these sources are very different from those of ultraluminous X-ray sources (ULXs) that have been found within spiral galaxies, suggesting that the two populations of X-ray-luminous objects have different formation mechanisms. The number of sources with apparent luminosities above 2 × 1039 ergs s-1 when determined using the distance of the galaxy is equal to the number of expected background active galactic nuclei and thus appears not to be associated with the galaxy, indicating that very luminous sources are absent or very rare in early-type galaxies. The lack of ULXs within elliptical galaxies strengthens the argument that ULXs are associated with recent star formation.
Standing Slow-Mode Waves in Hot Coronal Loops: Observations, Modeling, and Coronal Seismology

Strongly damped Doppler shift oscillations are observed frequently associated with flarelike events in hot coronal loops. In this paper, a review of the observed properties and the theoretical modeling is presented. Statistical measurements of physical parameters (period, decay time, and amplitude) have been obtained based on a large number of events observed by SOHO/SUMER and Yohkoh/BCS. Several pieces of evidence are found to support their interpretation in terms of the fundamental standing longitudinal slow mode. The high excitation rate of these oscillations in small- or micro-flares suggest that the slow mode waves are a natural response of the coronal plasma to impulsive heating in closed magnetic structure. The strong damping and the rapid excitation of the observed waves are two major aspects of the waves that are poorly understood, and are the main subject of theoretical modelling. The slow waves are found mainly damped by thermal conduction and viscosity in hot coronal loops. The mode coupling seems to play an important role in rapid excitation of the standing slow mode. Several seismology applications such as determination of the magnetic field, temperature, and density in coronal loops are demonstrated. Further, some open issues are discussed.
American Gastroenterological Association Technical Review on the Management of Hepatitis C

Jules L Dienstag,* John G Mchutchison** * Unidad Gastrointestinal (Servicios Medicos). Hospital General de Massachusetts, Departamento de Medicina y Oficina del Director de Educacion Medica, Escuela de Medicina de Harvard, Boston, Massachusetts. ** Instituto de Investigacion Clinica de Duke, Division de Gastroenterologia, Centro Medico de la Universidad de Duke. Durham, Carolina del Norte. Correspondence: Chair, Clinical Practice and Economics Committee, AGA National Office, c/o Membership Department, 4930 Del Ray Avenue, Bethesda, Maryland 20814. Fax: (301)654-5920.
Soft-edged magnet models for higher-order beam-optics map codes

Continuously varying surface and volume source-density distributions are used to model magnetic fields inside of cylindrical volumes. From these distributions, a package of subroutines computes on-axis generalized gradients and their derivatives at arbitrary points on the magnet axis for input to the numerical map-generating subroutines of the Lie-algebraic map code Marylie. In the present version of the package, the magnet menu includes: (1) cylindrical current-sheet or radially thick current distributions with either open boundaries or with a surrounding cylindrical boundary with normal field lines (which models high-permeability iron), (2) Halbach-type permanent multipole magnets, either as sheet magnets or as radially thick magnets, (3) modeling of arbitrary fields inside a cylinder by use of a fictitious current sheet. The subroutines provide on-axis gradients and their z derivatives to essentially arbitrary order, although in the present third- and fifth-order Marylie only the zeroth through sixth derivatives are needed. The formalism is especially useful in beam-optics applications, such as magnetic lenses, where realistic treatment of fringe-field effects is needed.
A WISE SURVEY OF CIRCUMSTELLAR DISKS IN TAURUS

We have compiled photometry at 3.4, 4.6, 12, and 22 μm from the all-sky survey performed by the Wide-field Infrared Survey Explorer (WISE) for all known members of the Taurus complex of dark clouds. Using these data and photometry from the Spitzer Space Telescope, we have identified members with infrared excess emission from circumstellar disks and have estimated the evolutionary stages of the detected disks, which include 31 new full disks and 16 new candidate transitional, evolved, evolved transitional, and debris disks. We have also used the WISE All-Sky Source Catalog to search for new disk-bearing members of Taurus based on their red infrared colors. Through optical and near-infrared spectroscopy, we have confirmed 26 new members with spectral types of M1-M7. The census of disk-bearing stars in Taurus should now be largely complete for spectral types earlier than ~M8 (M 0.03 M ☉).
Detecting Fraud: What Are Auditors' Responsibilities?

High-profile fraud cases have continued to make the news over the past few years. But exactly what are auditors' responsibilities when it comes to detecting fraud? The author of this article reveals that the auditing profession has come full circle-from being responsible to not being responsible for detecting fraud. But the volume and critical nature of fraud cases remain high, as do the number of auditing standards addressing this issue. The author explores this problem in depth, identifies situations where fraud may take place, and suggests various tools that auditors should use for fraud detection. © 2013 Wiley Periodicals, Inc.
A facile one-pot conversion of non-enolizable aldehydes to diazirines

Abstract A general route to monoalkyl diazirines from non-enolizable aldehydes through N -trimethylsilyl diaziridines is described.
Characterization of Thin Films using Micromechanical Structures

Micromechanical structures designed for material characterization through analysis of their nonlinear dynamic response are presented. The structures consist of a rigid movable mass supported by beams which are attached to the wafer substrate. The structures are designed so that they are geometrically constrained, which is the source of their nonlinearity. The nonlinearity is shown to be well modeled by Duffing’s equation for a stiffening spring and it is this model which is used to fit the test data to the desired mechanical properties, namely Young’s modulus, intrinsic stress and damping.
Extreme energetic particle decreases near geostationary orbit: A manifestation of current diversion within the inner plasma sheet

We consider a qualitative model of cross-tail current flow and suggest that when magnetic reconnection begins, the current effectively flows across the plasma sheet both earthward and tailward of the disruption region near the neutral line. We show that an enhanced cross-tail current earthward of this region would thin the plasma sheet substantially due to the magnetic pinch effect often studied in laboratory plasmas. This thinning would in turn affect the drift currents even closer toward the earth. In this way, a disruption and effective diversion of the cross-tail current throughout much of the inner portion of the plasma sheet could result and intense cross-tail current localized at the inner edge of the plasma sheet would lead to a very thin current-carrying region. This would explain the very taillike field and extreme particle dropouts often seen late in substorm growth phases. When the currents cannot be further enhanced within the inner plasma sheet (and when diffuse electron precipitation has sufficiently increased ionospheric conductivities) we expect an intense (≥106 A), very rapid increase of current flow through the auroral ionosphere. This latter phase would basically constitute the substorm expansion phase.
Dynamic impact of an elastically supported beam—large area contact

Abstract The dynamic contact problem of a rigid, smooth striker impacting an elastically supported beam is solved. Use is made of the superposition of an elastic layer solution together with an elementary beam theory solution that incorporates the dynamic effects. The problem is formulated in such a manner as to require the solution of a Volterra integral equation for each time increment. Numerical results are presented for various parameters.
Specialization and market development as engines of growth

Purpose – The purpose of this paper is to explain the following stylized facts. First, the share of household production in total output has fallen over time as the economy has grown. Second, services as a percent of GDP have risen at the same time.Design/methodology/approach – This paper constructs an original model of growth based on Adam Smith's notions of specialization and extent of the market. Growth depends on the specialization of labor in market production and learning‐by‐doing in transactions services. It is a model of sustained, but not infinite, growth.Findings – It is found that the model can replicate the above stylized facts for reasonable parameterizations.Originality/value – This paper shows that it is possible to build growth models that match the historic experience without relying in unbounded growth. Models like this may be very useful in understanding the processes that drive growth.
Variable-Rate Distributed Source Coding in the Presence of Byzantine Sensors

The distributed source coding problem is considered when the sensors, or encoders, are under Byzantine attack; that is, an unknown number of sensors have been reprogrammed by a malicious intruder to undermine the reconstruction at the fusion center. Three different forms of the problem are considered. The first is a variable-rate setup, in which the decoder adaptively chooses the rates at which the sensors transmit. An explicit characterization of the variable-rate minimum achievable sum rate is stated, given by the maximum entropy over the set of distributions indistinguishable from the true source distribution by the decoder. In addition, two forms of the fixed-rate problem are considered, one with deterministic coding and one with randomized coding. The achievable rate regions are given for both these problems, with a larger region achievable using randomized coding, though both are suboptimal compared to variable-rate coding.
A Brylinski filtration for affine Kac–Moody algebras

Abstract Braverman and Finkelberg have recently proposed a conjectural analogue of the geometric Satake isomorphism for untwisted affine Kac–Moody groups. As part of their model, they conjecture that (at dominant weights) Lusztig's q-analog of weight multiplicity is equal to the Poincare series of the principal nilpotent filtration of the weight space, as occurs in the finite-dimensional case. We show that the conjectured equality holds for all affine Kac–Moody algebras if the principal nilpotent filtration is replaced by the principal Heisenberg filtration. The main body of the proof is a Lie algebra cohomology vanishing result. We also give an example to show that the Poincare series of the principal nilpotent filtration is not always equal to the q-analog of weight multiplicity. Finally, we give some partial results for indefinite Kac–Moody algebras.
A Method for Representing the Configuration and Analyzing the Motion of Complex Cable-Pulley Systems

In this paper a systematic way of representing complex cable-pulley mechanism configurations and a method to analyze their motion is presented. This technique can also be used as an aid for synthesis. The cable-pulley system model that is being considered is planar and composed of three basic elements which are pulleys, blocks, and cables. A configuration table is used to identify the constraint equations by systematically defining the connections between the cables, pulleys, and blocks. The basic strategy is to use the constraint equations to generate the relationship between each variable and a subset of the variables identified as the inputs. A row reduction process on the system of constrainst equations identifies the number of inputs and ultimately generates the relationships of each variable to the input(s). Results with different input variables can be easily obtained by a simple column interchange process. Examples are given to illustrate the procedure.
Affine Weyl Groups in K-Theory and Representation Theory

We give an explicit combinatorial Chevalley-type formula for the equivariant K-theory of generalized flag varieties G/P which is a direct generalization of the classical Chevalley formula. Our formula implies a simple combinatorial model for the characters of the irreducible representations of G and, more generally, for the Demazure characters. This model can be viewed as a discrete counterpart of the Littelmann path model, and has several advantages. Our construction is given in terms of a certain R-matrix, that is, a collection of operators satisfying the Yang-Baxter equation. It reduces to combinatorics of decompositions in the affine Weyl group and enumeration of saturated chains in the Bruhat order on the (nonaffine) Weyl group. Our model easily implies several symmetries of the coefficients in the Chevalley-type formula. We also derive a simple formula for multiplying an arbitrary Schubert class by a divisor class, as well as a dual Chevalley-type formula. The paper contains other applications and examples.
Efficient entry to bicyclic lactones via van Halban-White cyclizations

The reactions of ketoalkynes with group 6 alkenylcarbene complexes give bicyclic lactones whose formation can be interpreted to be the result of a van Halban-White type double-cyclization of cross-conjugated ketenes of the type 6
Billiard-ball echo model

Photon echoes in gaseous media are explained with the use of a simple heuristic model in which the atoms behave like composite billiard balls. The laser providing the excitation pulses becomes an atom smasher which "splits" the atoms and then by judicious programming puts them back together again. The most general photon-echo reordering process is explained without recourse to formal analysis so that an intuitive feeling is obtained which works equally well for the ordinary two-pulse photon echo, the Raman echo, the trilevel echo, the grating echo, etc. A formal analysis of the billiard-ball echo model is presented in its support.
Brillouin scattering of exciton polaritons and additional boundary conditions

Abstract The importance of exciton damping, γ, on the Brillouin scattering efficiencies is pointed out. Brillouin scattering efficiencies have been calculated as a function of γ using two different additional boundary conditions (ABC). For γ larger than some value γ C , as assumed in an earlier calculation of Brenig, Zeyher and Birman, the dependence of the scattering efficiencies on incident photon energy is rather insensitive to the ABC used. However, for γ small compared with γ C the scattering efficiencies calculated with different ABC's show qualitative differences.
Hydrogen production at low temperature from methane on cerium and nickel based mixed oxides

Partial oxidation of methane (POM) to synthesis gas, CO þ H2, was investigated between 50 � C and 700 � C as a function of metal loading over cerium and nickel based CeNiXOY catalysts. At high temperature, 700 � C, a H2 yield of 100% is obtained. At 200 � C, an inter- esting yield of 34% is reached with a stable methane conversion of 70% and a H2 selectivity of 49%, only when the solid is previously in situ treated in H2 at 200 � C. Activated in H2 CeNixOY solids are hydrogen reservoirs. Different physico-chemical techniques were used to characterize the structural, dispersion and reduction properties of the solids. Depending on composition, a solid solution and/or a highly dispersed nickel oxide on ceria can be obtained. Ion sputtering followed by XPS analysis was very useful for estimating the size of small NiO crystallites present in the compounds. It is found that active nickel species belong to small clusters and/or to solid solution. Correlations among species present in solid and catalytic performances are discussed. An active site based on formation of anionic vacancies and a mechanism involving a heterolytic abstraction of a hydride species from methane are proposed. a 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.
THE OFF-NUCLEAR STARBURSTS IN NGC 4038/4039 (THE ANTENNAE GALAXIES)

Imaging of the Antennae galaxies (NGC 4038/4039) with the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope reveals large concentrations of star-forming activity away from both nuclei of the two merging galaxies. These images confirm earlier findings based on Infrared Space Observatory (ISO) data with lower angular resolution. The short-wavelength emission shows numerous compact sources identified as stellar clusters. At the longer wavelengths, bright, more amorphous and filamentary features correlate well with the known distributions of denser gas, warm dust, and H II regions. There are also fainter, more diffuse components at all wavelengths that permeate the entire region and extend into the two tidal tails. Nonstellar dust emission dominates the 5.8 and 8.0 μm images, accounting for as much as 79% of the light at 5.8 μm and 95% at 8 μm, averaged over the entire galaxy. Assuming that the nonstellar emission traces star formation, the IRAC data provide a view into the total underlying star-forming activities unaffected by obscuration. Using the flux ratio of nonstellar to stellar emission as a guide, we map the local star formation rate in the Antennae and compare that to similar measurements in both normal and infrared-luminous galaxies. This rate in the active regions is found to be as high as those seen in starburst and some ultraluminous infrared galaxies on a "per unit mass" basis. The two galactic centers actually have lower star-forming rates than the off-nuclear regions despite the presence of abundant dense gas and dust, suggesting that the latter is a necessary but not sufficient condition for ongoing star formation.
The interior structure of Jupiter: Consequences of Pioneer 10 data

Abstract Models of the Jovian interiors are based on theoretical equations of state of hydrogen and helium supported by a few experimental points and on observed parameters such as oblateness, gravitational coefficients, heat emission, magnetic fields, etc. The models fall into three categories: (1) those which assume a uniform and rather low H 2 /He ratio throughout the planet, (2) those in which this ratio is solar and thus higher, and (3) those which take into account the lack of complete miscibility of the two elements in the condensed state. Recent values of the observed parameters obtained by Pioneer 10 permit improvements of the first two models but also pose new questions: In the first category of models the new data indicate that the amount of hydrogen has to be increased while in the “solar” models which have a heavy core (made of SiO 2 , MgO, Fe, and Ni) the abundance of hydrogen has to be decreased, both changes pointing in the direction of incomplete miscibility present in the third category of models. It appears now also that within the limits of error the planet is in a hydrostatic equilibrium. The large heat emission and the need for an efficient source of internal heat is confirmed but the results do not indicate which one of the various possible mechanisms is favored although new evolutionary models suggest that the primordial heat may be insufficient. A new red spot has been discovered. Finally the presence of a highly eccentric and inclined magnetic field poses new problems, which are related to the pattern of internal convection and to the possibility of a north-south asymmetry of the interior. Further analysis of the available data may throw additional light on these questions.
Role of Ultrasound in Thyroid Disorders

Thyroid ultrasonography has established itself as a popular and useful tool in the evaluation and management of thyroid disorders, both malignant and benign. Although its use has traditionally been the domain of radiologists, surgeons and endocrinologists are increasingly integrating this technology into their daily clinical and operative practice. This article provides an overview of the relevant uses and indications for ultrasound in various thyroid diseases, describes characteristic ultrasound findings in these diseases, and reviews the relevant literature and guidelines concerning its uses.
Factors affecting job satisfaction of nurses who work in long-term care

A questionnaire developed by the authors was sent to 1000 nurses in various specialty areas. It was used to assess degree of job satisfaction, reasons for dissatisfaction, and the relationships of the work setting and sociodemographic data. Because the authors wanted to compare nurses who work primarily with older adults within and outside long-term care, the percentage of time spent caring for patients aged over 60 was also studied. The degree of job satisfaction between nurses working in long-term care was compared. A comparison of job satisfaction was also made between nurses working at least 75% of the time with older adults and nurses not working primarily with older adults. Factors causing job dissatisfaction in the long-term care group and the non-long-term care group were identified. Strategies to increase job satisfaction in long-term care were presented.
Extrinsic curvature dependence of Nielsen-Olesen strings

Abstract It is shown how to treat the degrees of freedom of Nielsen-Olesen vortices in the 3 + 1-dimensional U(1) Higgs model by a collective coordinate method. In the London limit, where the Higgs mass becomes infinite, the gauge and goldstone degrees of freedom are integrated out, resulting in the vortex world-sheet action. Introducing an ultraviolet cut-off mimics the effect of finite Higgs mass. This action is non-polynomial in derivatives and depends on the extrinsic curvature of the surface. Flat surfaces are stable if the coherence length is less than the penetration depth. It is argued that in the quantum abelian Higgs model, vortex world-sheets are dominated by branched polymers.
Discovery and Development of Folic-Acid-Based Receptor Targeting for Imaging and Therapy of Cancer and Inflammatory Diseases

In order to avoid the toxicities associated with prescription drug use today, we have explored novel methods for delivering drugs selectively to pathologic cells, thereby avoiding the collateral damage that accompanies their uptake by healthy cells. In this Account, we describe our quest for the ideal targeted therapeutic agent. This effort began with a search for ligands that would bind selectively to pathologic cells, displaying no affinity for healthy cells. After identification of an optimal targeting ligand, effort was focused on construction of linkers that would carry the attached drug to pathologic cells with receptors for the selected ligand. In the case of cancer, we exploited the well-characterized up-regulation of folate receptors on malignant cells to target folate-linked pharmaceuticals to cancer tissues in vivo. Drugs that have been linked to folic acid for tumor-selective drug delivery to date include (i) protein toxins, (ii) chemotherapeutic agents, (iii) gene therapy vectors, (iv) oligonucleotides (including small interfering RNA (siRNA)), (v) radioimaging agents, (vi) magnetic resonance imaging (MRI) contrast agents, (vii) liposomes with entrapped drugs, (viii) radiotherapeutic agents, (ix) immunotherapeutic agents, and (x) enzyme constructs for prodrug therapy. Current clinical trials of four folate-linked drugs demonstrate that folate receptor-targeting holds great promise for increasing the potency while reducing toxicity of many cancer therapies. In the course of developing folate-conjugated drugs for cancer, we discovered that folate receptors are also overexpressed on activated (but not resting or quiescent) macrophages. Recognizing that activated macrophages either cause or contribute to such diseases as rheumatoid arthritis, Crohn's disease, atherosclerosis, lupus, inflammatory osteoarthritis, diabetes, ischemia reperfusion injury, glomerulonephritis, sarcoidosis, psoriasis, Sjogren's disease, and vasculitis, we initiated studies aimed at developing folate-conjugated imaging and therapeutic agents for the diagnosis and treatment of such diseases. In very brief time, significant progress has been made towards identification of clinical candidates for targeted treatment of several inflammatory and autoimmune diseases. This Account summarizes the discovery and development of a variety of folate-targeted drugs for the diagnosis and therapy of cancers and inflammatory/autoimmune diseases.
Effects of current on vortex and transverse domain walls

By using the spin torque model in ferromagnets, we compare the response of vortex and transverse walls to the electrical current. For a defect-free sample and a small applied current, the steady-state wall mobility is independent of the wall structure. In the presence of defects, the minimum current required to overcome the wall pinning potential is much smaller for the vortex wall than for the transverse wall. During the wall motion, the vortex wall tends to transform to the transverse wall. We construct a phase diagram for the wall mobility and the wall transformation driven by the current.
Investigation of Radon-222 in Subsurface Waters as an Earthquake Predictor

Changes of radon-222 content of well waters in seismically active regions may provide earthquake precursor signals, according to reports of recent Chinese and Russian work. A high-precision ?-ray system for continuous monitoring of radon in wells and Springs has been developed at the Lawrence Berkeley Laboratory, where monitoring began in April 1975, and has been extended to other sites including the San Andreas fault zone.
A facile copper(I)-catalyzed homocoupling of terminal alkynes to 1,3-diynes with diaziridinone under mild conditions

A novel and efficient Cu(I)-catalyzed oxidative homocoupling of terminal alkynes with diaziridinone as an oxidant is described. Various terminal alkynes can be transformed into the corresponding 1,3-diynes in good yields. The reaction process is base-free, operationally simple, and amenable to the gram scale.
Visualizing classical and quantum probability densities for momentum using variations on familiar one-dimensional potentials

After briefly reviewing the definitions of classical probability densities for position, PCL(x), and for momentum, PCL(p), we present several examples of classical mechanical potential systems, mostly variations on such familiar cases as the infinite well and the uniformly accelerated particle for which the classical distributions can be easily derived and visualized. We focus especially on a simple potential which interpolates between the symmetric linear potential, V(x) = F|x|, and the infinite well, which can illustrate, in a mathematically straightforward way, how the divergent δ-function classical probability density for momentum for the infinite well can be seen to arise. Such examples can help students understand the quantum mechanical momentum-space wavefunction (and its corresponding probability density) in much the same way that other semiclassical techniques, such as the WKB approximation, can be used to visualize position-space wavefunctions.
Familial Hypercholesterolemia: Defective Binding of Lipoproteins to Cultured Fibroblasts Associated with Impaired Regulation of 3-Hydroxy-3-Methylglutaryl Coenzyme a Reductase Activity

Abstract Monolayers of cultured fibroblasts from normal human subjects bind 125I-labeled low-density lipoproteins with high affinity and specificity. High affinity binding of similar magnitude was not observed in cells from five unrelated subjects with the homozygous form of familial hypercholesterolemia. In normal cells incubated at 37°, the binding sites were saturated at a low-density lipoprotein concentration of 20 μg/ml. A maximum of approximately 250,000 molecules could be bound to each cell. Whole serum and very-low-density lipoproteins displaced 125I-labeled low-density lipoproteins from the binding sites, but high-density lipoproteins, the lipoprotein-deficient fraction of serum, and abetalipoproteinemic serum did not. This binding appears to be a required step in the process by which low-density lipoproteins normally suppress the synthesis of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, the rate-controlling enzyme in cholesterol biosynthesis. The demonstration of a defect in binding of low-density lipoproteins to cells from subjects with the homozygous form of familial hypercholesterolemia appears to explain the previously reported failure of lipoproteins to suppress the synthesis of this enzyme and hence may account for the overproduction of cholesterol that occurs in these cultured cells.
Fabrication and characterization of controllable grain boundary arrays in solution-processed small molecule organic semiconductor films

We have produced solution-processed thin films of 6,13-bis(tri-isopropyl-silylethynyl) pentacene with grain sizes from a few micrometers up to millimeter scale by lateral crystallization from a rectangular stylus. Grains are oriented along the crystallization direction, and the grain size transverse to the crystallization direction depends inversely on the writing speed, hence forming a regular array of oriented grain boundaries with controllable spacing. We utilize these controllable arrays to systematically study the role of large-angle grain boundaries in carrier transport and charge trapping in thin film transistors. The effective mobility scales with the grain size, leading to an estimate of the potential drop at individual large-angle grain boundaries of more than 1 volt. This result indicates that the structure of grain boundaries is not molecularly abrupt, which may be a general feature of solution-processed small molecule organic semiconductor thin films, where relatively high energy grain bounda...
DETERMINATIONS OF ANALOGUES OF GAUSS SUMS AND OTHER TRIGONOMETRIC SUMS

Explicit determinations of several classes of trigonometric sums are given. These sums can be viewed as analogues or generalizations of Gauss sums. In a previous paper, two of the present authors considered primarily sine sums associated with primitive odd characters. In this paper, we establish two general theorems involving both sines and cosines, with more attention given to cosine sums in the several examples that we provide.
Developmental facial abnormalities and the temporomandibular joint

An appreciation of normal and abnormal mandibular condyle growth, as summarized here, is an aid in the early recognition and proper treatment of developmental deformities of the face and TMJ.
Enhancing the catalytic performance of Pt/C catalysts using steam-etched carbon blacks as a catalyst support

XC72 carbon blacks were treated using a steam-etching technique. Pt catalysts using steam-etched carbon blacks (SECBs) as supports were developed for oxygen reduction reactions in polymer electrolyte fuel cells (PEFCs). The use of the steam-etched carbon blacks as a catalyst support can improve the dispersion uniformity of Pt nanoparticles on the surface of the support and can decrease the Pt particle size, as indicated by transmission electron microscopy (TEM) data. The overall catalytic performance of the catalysts using SECBs was better than that of the catalysts using non-SECBs. The mass activity of the Pt catalysts using SECBs etched for 1 h had the best catalytic performance for both the catalysts using SECBs and those using non-SECBs. In addition, the electrochemically active surface area of the Pt/SECBs significantly increased after etching. TEM results revealed that the center of the carbon black was more easily etched than the surface.
UP and the low and high hierarchies: A relativized separation

The low and high hierarchies within NP were introduced by Schoning in order to classify sets in NP. It is not known whether the low and high hierarchies include all sets in NP. In this paper, using the circuit lower-bound techniques of Hastad and Ko, we construct an oracle set relative to which UP contains a language that is not in any level of the low hierarchy and such that no language in UP is in any level of the high hierarchy. Thus, in order to prove that UP contains languages that are in the high hierarchy or that UP is contained in the low hierarchy, it is necessary to use nonrelativizable proof techniques. Since it is known that UPA is low for PPA for all setsA, our result also shows that the interaction between UP and PP is crucial for the lowness of UP for PP; changing the base class to any level of the polynomial-time hierarchy destroys the lowness of UP.
MARKOV QUANTUM FIELDS ON A MANIFOLD

We study scalar quantum field theory on a compact manifold. The free theory is defined in terms of functional integrals. For positive mass it is shown to have the Markov property in the sense of Nelson. This property is used to establish a reflection positivity result when the manifold has a reflection symmetry. In dimension d=2 we use the Markov property to establish a sewing operation for manifolds with boundary circles. Also in d=2 the Markov property is proved for interacting fields.
Synthesis of isoquinolines and pyridines by the palladium-catalyzed iminoannulation of internal alkynes.

A wide variety of substituted isoquinoline, tetrahydroisoquinoline, 5,6-dihydrobenz[f]isoquinoline, pyrindine, and pyridine heterocycles have been prepared in good to excellent yields via annulation of internal acetylenes with the tert-butylimines of o-iodobenzaldehydes and 3-halo-2-alkenals in the presence of a palladium catalyst. The best results are obtained by employing 5 mol % of Pd(OAc)2, an excess of the alkyne, 1 equiv of Na2CO3 as a base, and 10 mol % of PPh3 in DMF as the solvent. This annulation methodology is particularly effective for aryl- or alkenyl-substituted alkynes. When electron-rich imines are employed, this chemistry can be extended to alkyl-substituted alkynes. Trimethylsilyl-substituted alkynes also undergo this annulation process to afford monosubstituted heterocyclic products absent the silyl group.
Modeling in paleoceanography

The two last decades of research in paleoceanography are characterized by extensive data collection and by the development of numerous hypotheses based on these data. Both the nature of the thermohaline circulation and the nature of the surface circulation during past times are currently being debated. Physical models of the ocean circulation are beginning to play an important role in these debates. The models range from highly simplified mathematical representations intended to illustrate physical principles to three-dimensional time-dependent global models intended to simulate temperature, salinity and flow fields. At the very least such models can be applied to explore the limitations or appropriateness of various assumptions in paleoceanography. At the very best, paleoceanographic data may be used as a verification of simulations of past oceans.
A LESS RESTRICTIVE BRIANCON-SKODA THEOREM WITH COEFFICIENTS

The Briancon–Skoda theorem in its many versions has been studied by algebraists for several decades. In this paper, under some assumptions on an F-rational local ring (R,m), and an ideal I of R of analytic spread l and height g<l, we improve on two theorems by Aberbach and Huneke. Let J be a reduction of I. We first give results on when the integral closure of Il+w is contained in the product Jw+1I[l−1], for any integer w⩾0, where, given any primary decomposition of I, I[l−1] is the intersection of the primary components of I of height at most l−1. In the case that R is also Gorenstein, we give results on when the integral closure of Il−1 is contained in J.
Spintronics: A nanomagnet oscillator.

A direct electrical current can drive high-frequency oscillations of the magnetization of a nanomagnet. A current-tunable microwave oscillator has now been demonstrated that shows large-amplitude oscillations.
Two Remarks on Rectangular Mixed Finite Elements for Elasticity

The lowest order nonconforming rectangular element in three dimensions involves 54 degrees of freedom for the stress and 12 degrees of freedom for the displacement. With a modest increase in the number of degrees of freedom (24 for the stress), we obtain a conforming rectangular element for linear elasticity in three dimensions. Moreover, unlike the conforming plane rectangular or simplicial elements, this element does not involve any vertex degrees of freedom. Second, we remark that further low order elements can be constructed by approximating the displacement with rigid body motions. This results in a pair of conforming elements with 72 degrees of freedom for the stress and 6 degrees of freedom for the displacement.
Ruthenium-Catalyzed Tandem Olefin Migration/Aldol and Mannich-Type Reactions in Water and Protic Solvents

Cross-coupling between 3-buten-2-ol (2) and aldehyde in the presence of a catalytic amount of [RuCl2(PPh3)3] has been developed, through a tandem olefin migration/aldol reaction in a water/toluene mixture. The presence of In(OAc)3 promoted the aldol reaction with α-vinylbenzyl alcohol (4) and aldehyde, while treatment of 3-buten-2-ol (2) with imines generated Mannich-type reaction products; syn isomers were formed as the major diastereomers for the aldol products 3a−3g and 5a−5e and the Mannich products 7a−7g. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)