cssi/SciSciGPT-SciSciNet huggingface dataset:
Three-dimensional flow calculations for a projectile with standard and dome bases

Test firings of the 155-mm XM825 artillery projectile have shown that its flight performance was affected by configurational changes to the base cavity. This was an unexpected result, and a clear understanding of why these changes affected the flight behavior did not exist. A computational study has been made for the two different base-cavity configurations which were flight tested. Flowfield computations have been performed at 0.8 <M< 1.5 and a = 4.0 deg using a recently developed three-dimensional Navier-Stokes code. The computed results show the qualitative features of the base region flowfield for the two base cavities. The base changes are found to alter the recirculation patterns in the wake, which in turn affect the expansion at the base corner. These changes in the flow structure contribute to small changes in the base pressure. Aerodynamic force and moment coefficients have been obtained from the computed pressures and are presented as a function of Mach number. Computed results show small differences in normal force and pitching moment coefficients similar to that found in the range data.
Therapeutic ultrasound: Its application in drug delivery

Ultrasound is best known for its imaging capability in diagnostic medicine. However, there have been considerable efforts recently to develop therapeutic uses for it. The purpose of this review is to summarize some of the recent advances made in the area of therapeutic ultrasound as they relate to drug delivery. In particular, this review will focus on the applications of ultrasound to enhance the delivery and effect of three distinctive therapeutic drug classes: chemotherapeutic, thrombolytic, and gene-based drugs. In addition, ultrasound contrast agents have been recently developed for diagnostic ultrasound. New experimental evidence suggests that these contrast agents can be used as exogenous cavitation nuclei for enhancement of drug and gene delivery. Thus, brief review of this new class of agents and their roles in drug delivery will also be provided. By comparison to diagnostic ultrasound, progress in therapeutic use of ultrasound has been somewhat limited. The recent successes in ultrasound-related drug delivery research positions ultrasound as therapeutic tool for drug delivery in the future. © 2002 John Wiley & Sons, Inc. Med Res Rev, 22, No. 2, 204–223, 2002; DOI 10.1002/med.10004
Magnetic silica supported copper: a modular approach to aqueous Ullmann-type amination of aryl halides

One-pot synthesis of a magnetic silica supported copper catalyst has been described via in situ generated magnetic silica (Fe3O4@SiO2); the catalyst can be used for the efficacious amination of aryl halides in aqueous medium under microwave irradiation.
Distribution of particles which produces a desired radiation pattern

Abstract If A q ( β , α , k ) is the scattering amplitude, corresponding to a potential q ∈ L 2 ( D ) , where D ⊂ R 3 is a bounded domain, and e i k α · x is the incident plane wave, then we call the radiation pattern the function A ( β ) ≔ A q ( β , α , k ) , where the unit vector α , the incident direction, is fixed, and k > 0 , the wavenumber, is fixed. It is shown that any function f ( β ) ∈ L 2 ( S 2 ) , where S 2 is the unit sphere in R 3 and β is the scattering direction, can be approximated with any desired accuracy by a radiation pattern: ∥ f ( β ) - A ( β ) ∥ L 2 ( S 2 ) e , where e > 0 is an arbitrary small fixed number. The potential q, corresponding to A ( β ) , depends on f and e . There is a one-to-one correspondence between the above potential and the density of the number of small acoustically soft particles D m ⊂ D , 1 ⩽ m ⩽ M , distributed in an a priori given bounded domain D ⊂ R 3 . Acoustically soft means that the Dirichlet condition is satisfied on the boundary of D m . The geometrical shape of a small particle D m is arbitrary, the boundary S m of D m is Lipschitz uniformly with respect to m. The wave number k and the direction α of the incident upon D plane wave are fixed. It is shown that a suitable distribution of the above particles in D can produce the scattering amplitude A ( α ′ , α ) , α ′ , α ∈ S 2 , at a fixed k > 0 , arbitrarily close in the norm of L 2 ( S 2 × S 2 ) to an arbitrary given scattering amplitude f ( α ′ , α ) , corresponding to a real-valued potential q ∈ L 2 ( D ) , i.e., corresponding to an arbitrary given refraction coefficient in D.
The Value of Federal Sponsorship: The Case of Freddie Mac

The Federal Housing Enterprises Financial Safety and Soundness Act of 1992 attempts to limit the risk borne by the taxpayer due to federal sponsorship of the Federal Home Loan Mortgage Corporation (FHLMC) and the Federal National Mortgage Association by: (1) controlling their range of activities; (2) requiring a level of capital sufficient to absorb substantial losses; and (3) providing a mechanism for closure if capital is insufficient. This article estimates the impact of the capital standards on the value to the FHLMC of federal sponsorship. Although FHLMC's level of capital exceeds requirements, the federal government still bears a nontrivial portion of the FHLMC's risk.
Strongly coupled gauge theories: high and low temperature behavior of non-local observables

We explore the high and low temperature behavior of non-local observables in strongly coupled gauge theories that are dual to AdS. We develop a systematic expansion for equal time two-point correlation, spatial Wilson loops and entanglement entropy at finite temperature using the AdS/CFT correspondence, leading to analytic expressions for these observables at high and low temperature limits. This approach enables the identification of the contributions of different regions of the bulk geometry to these gauge theory observables.
Thiazoles in organic synthesis. Novel syntheses of menthanes and eremophilanes

Abstract Acetylcnic thiazoles of proper design have been shown to undergo an intramolecular Diels-Alder reaction leading to fused-ring thiophene derivatives. When appropriately substituted, these latter materials can be readily converted to terpenes of the menthane and eremophilane class by Raney-nickel desulfurization
High‐silica glass inclusions in olivine of Luna‐24 samples

Optical examination of nine polished grain mounts of Luna-24 drillcore material (0.09-0.50 mm size) revealed melt inclusions in olivine crystals. Two inclusions consist of clear glass with exceptionally high Si, yet contain no visible daughter minerals, and have had no reaction effects with the olivine walls. Their compositions (one has SiO2 93.8, Al2O3 1.51, FeO 2.32, MgO 1.61, CaO 0.06, Na2O <0.05, K2O 0.11, total 99.41%; the other is similar) are unique and quite unlike the high-Si, high-K melt of granitic composition that is found as inclusions in late-stage minerals of these (and the Apollo) samples, from silicate liquid immiscibility. The host olivines are Fo73 and Fo51. The origin of the melt in the inclusions and the lack of reaction effects are perplexing unsolved problems.
Mixed valent sites in biological electron transfer.

Many of the active sites involved in electron transfer (ET) in biology have more than one metal and are mixed valent in at least one redox state. These include CuA, and the polynuclear Fe–S clusters which vary in their extent of delocalization. In this tutorial review the relative contributions to delocalization are evaluated using S K-edge X-ray absorption, magnetic circular dichroism and other spectroscopic methods. The role of intra-site delocalization in ET is considered.
Analysis and visualization of heart motion

Inferring dynamic behavior of the heart from its image sequences is a very important research area in biomedical engineering. It provides an invaluable tool for noninvasive evaluation of myocardial functions. This paper presents estimation algorithms for the analysis of heart motion and deformation over a cardiac cycle, as well as the visualization techniques for the animation of moving heart evolution. The first part of the paper is devoted to the analysis of the heart motion and deformation. The research is based on the general belief that the human heart undergoes both global motion and local deformation, and is conducted on the angiographic data of the heart. The authors identify the global motion as the relative position and orientation change of the heart as a whole and estimate the motion parameters from the 3- D data of the bifurcation points. They also develop a recursive algorithm for estimating global motion and object shape in order to combat the biased distribution of the bifurcation points. Upon compensation for the global motion, a tensor analysis based approach is introduced to parameterize the deformation of localized region. The estimated stretch tensors give the directions and magnitudes of extreme deformation for each localized region. In the second part of the paper, several visualization techniques are presented to vividly examine the spatial and time varying nature of the heart. Animations of global motion compensation and local deformation evolution are generated using the original data and estimation results. Display showing the heart in slow motion is created by interpolating original and estimated data between image frames. Visualization operations such as camera and lighting manipulation, polygon outlining, color coding, and so on are applied to the data to reveal the complex nature of the beating heart.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Congenital hypomyelination neuropathy in a newborn infant: unusual cause of diaphragmatic and vocal cord paralyses

We report a case of congenital hypomyelination neuropathy presenting at birth. The infant had generalized hypotonia and weakness. There was decreased respiratory effort along with a right phrenic nerve and left vocal cord paralyses. Tongue fasciculations were present. Deep tendon reflexes were absent in the upper extremities and hypoactive (1+) in the lower extremities. Magnetic resonance imaging of the head revealed no intracranial abnormalities, including normal cerebral myelination. Nerve conduction study showed absence of motor and sensory action potentials in the hands when the nerves in the upper limbs were stimulated. A motor response could be elicited only in the proximal leg muscles. Needle electromyography study was normal in the proximal limb muscles, but showed active denervation in the distal muscles of the arm and leg. These findings were thought to be consistent with a length-dependent sensorimotor peripheral polyneuropathy of axonal type with greater denervation of the distal muscles. A biopsy of the quadriceps muscle showed mild variability in fiber diameter, but no group typing or group atrophy. The muscle fibers showed no intrinsic abnormalities. Biopsy of the sural nerve showed scattered axons with very thin myelin sheaths. There was also a nearly complete loss of large diameter myelinated fibers. No onion bulb formations were noted. These findings were thought to be consistent with congenital hypomyelination neuropathy with a component of axonopathy. DNA analysis for identification of previously characterized mutations in the genes MPZ, PMP22, and EGR2 was negative. Several attempts at extubation failed and the infant became increasingly ventilator-dependent with increasing episodes of desaturation and hypercapnea. He also developed increasing weakness and decreased movement of all extremities. He underwent surgery at 2 months of age for placement of a gastrostomy tube and a tracheostomy. He was discharged from the hospital on a ventilator at 6 months of age. The infant was 13 months old at the time of submission of this report. Although he appears cognitively normal, he remains profoundly hypotonic and is on a home ventilator. There was no evidence of progressive weakness. Congenital hypomyelination neuropathy is a rare form of neonatal neuropathy that should be considered in the differential diagnosis of a newborn with profound hypotonia and weakness. It appears to be a heterogeneous disorder with some of the cases being caused by specific genetic mutations.
White dwarf pulsations: A review

The DA white dwarfs are those which show only the Stark-broadened lines of hydrogen in thei r spectra. They comprise about 80% of the total white dwarf population. A subset of the DA dwarfs, the ZZ Ceti stars, form a highly homogeneous class of nonradially pulsating variable stars. In this paper we shall review the observations from which both the physical properties of the stars and the characteristics of the pulsations have been derived. Data obtained since the last review of these variables (Robinson 1979) is stressed, as these data are forcing a somewhat revised understanding of the ZZ Ceti stars and their relationship to investigations of white dwarfs and to pulsating variable stars, in general.
Interface effects with Ga0.47In0.53As layers on InP substrates prepared by organometallic chemical vapor deposition

Abstract Lattice-matched Ga0.47In0.53As was epitaxially grown on InP substrates by the reaction of triethylgallium, triethylindium and arsine. The mobility and carrier concentration in these layers were determined by sequential etch and Hall effect measurements made on the grown layers. These measurements show a considerable fall-off in mobility in the vicinity of the interface, accompanied by a rapid increase in electron concentration. In situ chloride etching of the substrate, prior to GaInAs growth, is shown to reduce significantly but not eliminate these interface effects. In this paper we outline possible reasons for these effects, based on measurements made on films grown with and without substrate etching and also on measurements of the effect of etching on the substrate itself.
Evaluation of Kalman filtering for network time keeping

Time information is critical for a variety of applications in distributed environments that facilitate pervasive computing and communication. This work describes and evaluates a novel Kalman filtering algorithm for end-to-end time synchronization between a client computer and a server of "true" time [e.g., a Global Positioning System (GPS) source] using messages transmitted over packet-switched networks, such as the Internet. The messages exchanged have the network time protocol (NTP) format, and the algorithm evaluated, is performed only at the client side. The Kalman filtering algorithm is compared to two other techniques widely used, based on linear programming and statistical averaging, and the experiments involve independent consecutive measurements (Gaussian case) or measurements exhibiting long-range dependence (self-similar case). Performance is evaluated according to the estimation error of frequency offset and time offset between client and server clock, the standard deviation of the estimates and the number of packets used for a specific estimation. The algorithms could exploit existing NTP infrastructure, and a specific example is presented.
The penalized profile sampler

The penalized profile sampler for semiparametric inference is an extension of the profile sampler method [B.L. Lee, M.R. Kosorok, J.P. Fine, The profile sampler, Journal of the American Statistical Association 100 (2005) 960-969] obtained by profiling a penalized log-likelihood. The idea is to base inference on the posterior distribution obtained by multiplying a profiled penalized log-likelihood by a prior for the parametric component, where the profiling and penalization are applied to the nuisance parameter. Because the prior is not applied to the full likelihood, the method is not strictly Bayesian. A benefit of this approximately Bayesian method is that it circumvents the need to put a prior on the possibly infinite-dimensional nuisance components of the model. We investigate the first and second order frequentist performance of the penalized profile sampler, and demonstrate that the accuracy of the procedure can be adjusted by the size of the assigned smoothing parameter. The theoretical validity of the procedure is illustrated for two examples: a partly linear model with normal error for current status data and a semiparametric logistic regression model. Simulation studies are used to verify the theoretical results.
Topological Disorder Operators in Three-Dimensional Conformal Field Theory

Many abelian gauge theories in three dimensions flow to interacting conformal field theories in the infrared. We define a new class of local operators in these conformal field theories which are not polynomial in the fundamental fields and create topological disorder. They can be regarded as higher-dimensional analogues of twist and winding-state operators in free 2d CFTs. We call them monopole operators for reasons explained in the text. The importance of monopole operators is that in the Higgs phase, they create Abrikosov-Nielsen-Olesen vortices. We study properties of these operators in three-dimensional QED using large N-f expansion. In particular, we show that monopole operators belong to representations of the conformal group whose primaries have dimension of order N-f. We also show that monopole operators transform non-trivially under the flavor symmetry group, with the precise representation depending on the value of the Chern-Simons coupling.
Effects of stream-associated fluctuations upon the radial variation of average solar-wind parameters

The effects of nonlinear fluctuations due to solar wind streams upon radial gradients of average solar wind parameters are computed, using a numerical MHD model for both spherically symmetric time dependent and corotating equatorial flow approximations. Significant effects of correlations are found between fluctuations upon the gradients of azimuthal magnetic fields, radial velocity, density and azimuthal velocity. Between 400 to 900 solar radii stream interactions have transferred the major portion of the angular momentum flux to the magnetic field; at even greater distances the plasma again carries the bulk of the angular momentum flux. The average azimuthal component of the magnetic field may decrease as much as 10% faster than the Archimedean spiral out to 6 AU due to stream interactions, but this result is dependent upon inner boundary conditions.
Geographic max-flow and min-cut under a circular disk failure model

Failures in fiber-optic networks may be caused by natural disasters, such as floods or earthquakes, as well as other events, such as an Electromagnetic Pulse (EMP) attack. These events occur in specific geographical locations, therefore the geography of the network determines the effect of failure events on the network's connectivity and capacity.In this paper we consider a generalization of the min-cut and max-flow problems under a geographic failure model. Specifically, we consider the problem of finding the minimum number of failures, modeled as circular disks, to disconnect a pair of nodes and the maximum number of failure disjoint paths between pairs of nodes. This model applies to the scenario where an adversary is attacking the network multiple times with intention to reduce its connectivity. We present a polynomial time algorithm to solve the geographic min-cut problem and develop an ILP formulation, an exact algorithm, and a heuristic algorithm for the geographic max-flow problem.
Risk-aware management of distributed energy resources

High wind energy penetration critically challenges the economic dispatch of current and future power systems. Supply and demand must be balanced at every bus of the grid, while respecting transmission line ratings and accounting for the stochastic nature of renewable energy sources. Aligned to that goal, a network-constrained economic dispatch is developed in this paper. To account for the uncertainty of renewable energy forecasts, wind farm schedules are determined so that they can be delivered over the transmission network with a prescribed probability. Given that the distribution of wind power forecasts is rarely known, and/or uncertainties may yield non-convex feasible sets for the power schedules, a scenario approximation technique using Monte Carlo sampling is pursued. Upon utilizing the structure of the DC optimum power flow (OPF), a distribution-free convex problem formulation is derived whose complexity scales well with the wind forecast sample size. The efficacy of this novel approach is evaluated over the IEEE 30-bus power grid benchmark after including real operation data from seven wind farms.
Unusual Arginine Formations in Protein Function and Assembly: Rings, Strings, and Stacks

Protein–protein interfaces are often stabilized by a small number of dominant contacts, exemplified by the overrepresentation of arginine residues at oligomerization interfaces. Positively charged arginines are most commonly involved in ion pairs of opposite charge; however, previous work of Scheraga and co-workers described the stable, close range interaction between guanidinium pairs in a solvated environment. To extend this work, we searched over 70 thousand protein structures and complexes for unusual formations of arginine residues supported by the electron density. Symmetry transformations were used to generate full assemblies. Clusters of four to eight arginine residues with Cζ–Cζ distances <5 A, organized as rings with four to eight members, stacks of two arginines, and strings of stacked arginines, are commonly located at the interfaces of oligomeric proteins. The positive charge is properly balanced by negatively charged counterions in about 90% of the cases. We also observed planar stacking of ...
On non-separating simple closed curves in a compact surface

Abstract We introduce a semi-algebraic structure on the set  of all isotopy classes of non-separating simple closed curves in any compact oriented surface and show that the structure is finitely generated. As a consequence, we produce a natural finite dimensional linear representation of the mapping class group of the surface. Applications to the Teichmuller space, Thurston's measured lamination space, the harmonic Beltrami differentials, and the first cohomology groups of the surface are discussed.
Aerobic and anaerobic storage of single-pass, chopped corn stover.

Corn stover has great potential as a biomass feedstock due its widespread availability. However, storage characteristics of moist corn stover harvested from single-pass harvesters have not been well quantified. In 2007, whole-plant corn stover at 19.1–40.3% (w.b.) moisture content was stored for 237 days in aerobic piles, one covered and one uncovered, as well an anaerobic silo bag. In 2008, two stover materials—whole plant and cob/husk from 31.7% to 58.1% (w.b.) moisture—were stored for 183 or 204 days in covered and uncovered anaerobic piles, ventilated bags, or anaerobic silo bags. Stover stored in uncovered piles was rehydrated by precipitation, which increased biological activity resulting in dry matter (DM) losses from 8.2% to 39.1% with an average of 21.5%. Stover in covered piles was successfully conserved when the average moisture was less than 25% (w.b.) with DM losses of 3.3%. Stover above 36% (w.b.) moisture and piled under a plastic cover had DM losses from 6.4% to 20.2% with an average of 11.9%. Localized heating occurred in the aerobic piles when moisture was above 45% (w.b.) which lead to temperatures where spontaneous combustion might be a concern (i.e., >70°C). Ambient air blown through a center tube in the ventilated storage bag dried stover near the tube to an average of 24.2% (w.b.), but the remainder of the bag averaged 46.8% (w.b.) at removal. Loss of DM ranged from 7.4% to 22.0% with an average of 11.8% with this storage method. Stover was most successfully conserved in the bags where anaerobic conditions were maintained. Under anaerobic conditions, DM losses ranged from 0.2% to 0.9%. When anaerobic conditions were not maintained in the silo bag, DM losses averaged 6.1% of DM. Anaerobic storage is the best solution for conserving the value of moist corn stover.
Quantum mechanics as quantum measure theory

The additivity of classical probabilities is only the first in a hierarchy of possible sum rules, each of which implies its successor. The first and most restrictive sum rule of the hierarchy yields measure theory in the Kolmogorov sense, which is appropriate physically for the description of stochastic processes such as Brownian motion. The next weaker sum rule defines a generalized measure theory which includes quantum mechanics as a special case. The fact that quantum probabilities can be expressed "as the squares of quantum amplitudes" is thus derived in a natural manner, and a series of natural generalizations of the quantum formalism is delineated. Conversely, the mathematical sense in which classical physics is a special case of quantum physics is clarified. The present paper presents these relationships in the context of a "realistic" interpretation of quantum mechanics.
A Theory of Vortex Merger

This paper discusses a 2D vortex merger for the particular case of a weak point vortex and an extended vortex of nearly circular cross section. A Hamiltonian analysis describes the interaction of the point vortex with surface waves on the extended vortex. Critical layers around the extended vortex are introduced where ``point vortex--surface wave'' resonances occur. Vortex merger occurs only when there is an overlap of neighboring critical layers. In this case the point vortex cascades through a sequence of resonances as it spirals in and merges with the extended vortex.
HIL-based finite-element design optimization process for the computational prototyping of electric motor drives

Summary form only given. An online hardware-in-the-loop finite-element (FE)-based design optimization procedure is developed for the computational prototyping of coupled electric motor-drive system. A design optimization case for development of permanent magnet (PM) machine drive is presented. The physical representation of the machine is achieved by modeling the machine as a current adjustable load. The mutual interaction of the machine and the existing drive is taken into account by physical connection of the drive to a current adjustable load. The current adjustable load can be automatically renewed due to the design parameter changes of the machine being designed in an optimization process. The optimal design of the PM machine example is realized using the proposed technique and both numerical and test results are discussed.
Optimization of antenna configuration for MIMO systems

In this letter, we investigate the issue of selecting the number of antennas at the base station and at the mobile to optimize ergodic capacity of a multiple-input/multiple-output system, when the costs of implementing antennas at the base station and at the mobile are unequal. Total system capacity, defined as a linear combination of the uplink and downlink ergodic capacity, is used as the objective function to be maximized. The asymptotic expression for the ergodic capacity is used as an approximation. The limiting case gives some insight on how the ratio of the number of antennas at the base station to the number of antennas at the mobile may change with signal-to-noise ratio and cost ratio when the total system capacity is maximized.
Detonating Failed Deflagration Model of Thermonuclear Supernovae. II. Comparison to Observations

We develop and demonstrate the methodology of testing multidimensional supernova models against observations by studying the properties of one example of the detonation from failed deflagration (DFD) explosion model of thermonuclear supernovae. Using time-dependent multidimensional radiative transfer calculations, we generate the synthetic broadband optical light curves, near-infrared light curves, color evolution curves, full spectral time series, and spectropolarization of the model, as seen from various viewing angles. All model observables are critically evaluated against examples of well-observed, standard Type Ia supernovae (SNe Ia). We explore the consequences of the intrinsic model asphericity by studying the dependence of the model emission on viewing angle, and by quantifying the resulting dispersion in (and internal correlations between) various model observables. These statistical properties of the model are also evaluated against those of the available observational sample of SNe Ia. On the whole, the DFD model shows good agreement with a broad range of SN Ia observations. Certain deficiencies are also apparent, and point to further developments within the basic theoretical framework. We also identify several intriguing orientation effects in the model that suggest ways in which the asphericity of SNe Ia may contribute to their photometric and spectroscopic diversity and, conversely, how the relative homogeneity of SNe Ia constrains the degree of asymmetry allowable in the models. The comprehensive methodology adopted in this work proves an essential component of developing and validating theoretical supernova models, and helps motivate and clearly define future directions in both the modeling and the observation of SNe Ia.
Adaptive mesh refinement in strain localization problems

An adaptive meshing method tailored to problems of strain localization is given. The adaption strategy consists of equi-distributing the variation of the velocity field over the elements of the mesh. A heuristic justification for the use of variations as indicators is advanced, and possible connections with interpolation error bounds are discussed. Meshes are constructed by Delaunay triangulation. It is shown how the Hu-Washizu principle determines a consistent transfer operator for the state variables. Examples of application are given which demonstrate the versatility of the method.
Highly Enantioselective Proton-Initiated Polycyclization of Polyenes

This report describes the synthesis of a range of chiral polycyclic molecules (tricyclic to pentacyclic) from achiral polyene precursors by enantioselective proton-initiated polycyclization promoted by the 1:1 complex of o,o'-dichloro-BINOL and SbCl(5). Excellent yields (ca. 90% per ring formed) and enantioselectivety (20:1 to 50:1) were obtained. The process is practical as well as efficient, because the chiral ligand is both readily prepared from R,R- or S,S-BINOL and easily recovered from the reaction mixture by extraction.
Modeling film-coolant flow characteristics at the exit of shower-head holes

Abstract The coolant flow characteristics at the hole exits of a film-cooled blade are derived from an earlier study where the hole pipes and coolant plenum were also discretized. The blade chosen is the VKI rotor with three staggered rows of shower-head holes. The present analysis applies these flow characteristics at the shower-head hole exits. A multi-block three-dimensional Navier–Stokes code with Wilcox's k – ω model is used to compute the heat transfer coefficient on the film-cooled turbine blade. A reasonably good comparison with the experimental data as well as with the more complete earlier analysis where the hole pipes and coolant plenum were also gridded is obtained. If the 1/7th power law is assumed for the coolant flow velocity and temperature distributions at the hole exits, considerable differences in the heat transfer coefficient on the blade surface, especially in the leading-edge region, are observed even though the span-averaged values of h match well with the experimental data. This calls for spatially-resolved experimental data near film-cooling holes on a blade for better validation of the code.
Defining the Scope of Your Evaluation

One challenge of conducting evaluations is finding the right questions to guide the work. A clear purpose for a study gives the evaluator a good sense of what information can answer the questions, and helps frame the scope of the project as a whole. Knowing the scope of the evaluation project provides a sense of the resources needed. A common pitfall for those getting started with evaluation is trying to carry out a project before thinking about the overall purpose of the evaluation. This article provides a brief overview of defining clear and concise evaluation questions and thinking about the overall scope of an evaluation project. Examples include questions and strategies used in small, medium, and large-scale studies.
Sensor data fusion for body state estimation in a hexapod robot with dynamical gaits

We report on a hybrid 12-dimensional full body state estimator for a hexapod robot executing a jogging gait in steady state on level terrain with regularly alternating ground contact and aerial phases of motion. We use a repeating sequence of continuous time dynamical models that are switched in and out of an extended Kalman filter to fuse measurements from a novel leg pose sensor and inertial sensors. Our inertial measurement unit supplements the traditionally paired three-axis rate gyro and three-axis accelerometer with a set of three additional three-axis accelerometer suites, thereby providing additional angular acceleration measurement, avoiding the need for localization of the accelerometer at the center of mass on the robot's body, and simplifying installation and calibration. We implement this estimation procedure offline, using data extracted from numerous repeated runs of the hexapod robot RHex (bearing the appropriate sensor suite) and evaluate its performance with reference to a visual ground-truth measurement system, comparing as well the relative performance of different fusion approaches implemented via different model sequences
Complete Optical Neurophysiology: Toward Optical Stimulation and Recording of Neural Tissue

Direct optical methods to stimulate and record neural activity provide artifact-free, noninvasive, and noncontact neurophysiological procedures. For stimulation, focused mid-infrared light alters membrane potential and activates individual neural processes. Simultaneous intrinsic scattered light parameters, including birefringence changes, can record neural activity with signals similar to potentiometric dyes. The simultaneous combination of optical stimulation and optical recording techniques provide the potential for powerful tools that may someday remove the need for invasive wires during electrophysiological recordings.
The Southern Ocean’s grip on the northward meridional flow

Abstract A ‘quasi-island’ approach for examining the meridional flux of warm and intermediate water from the Southern Ocean into the South Atlantic, the South Pacific and the Indian Ocean has recently been proposed ( Nof, 2000a , Nof, 2002 ). This approach considers the continents to be ‘pseudo islands’ in the sense that they are entirely surrounded by water, but have no circulation around them. The method employs an integration of the linearized momentum equations along a closed contour containing the continents. This allows the meridional transport into these oceans to be computed without having to find the detailed solution to the complete wind-thermohaline problem. The solution gives two results; one expected, the other unexpected. It shows that, as expected, about 9±5 Sv of upper and intermediate water enter the South Atlantic from the Southern Ocean. The unexpected result is that the Pacific–Indian Ocean system should contain a ‘shallow’ meridional overturning cell carrying 18±5 Sv. What is meant by shallow here is that the cell does not extend all the way to the bottom (as it does in the Atlantic) but is terminated at mid-depth. (This reflects the fact that there is no bottom water formation in the Pacific.) Both of these calculations rely on the observation that there is almost no flow through the Bering Strait and on the assumption that there is a negligible pressure torque on the Bering Strait’s sill. Here, we present a new and different approach, which does not rely on either of the above two conditions regarding the Bering Strait and yet gives essentially the same result. The approach does not involve any quasi-island calculation but rather employs an integration of the linearized zonal momentum equation along a closed open-water latitudinal belt connecting the tips of South Africa and South America. The integration relies on the existence of a belt (corridor) where the linearized general circulation equations are valid. It allows for a net northward mass flux through either the Sverdrup interior or the western boundary currents. It is found that the belt-corridor approach gives 29±5 Sv for the total meridional flux of surface and intermediate water from the Southern Ocean. This agrees very well with the quasi-island calculations, which give a total northward flux of 27±5 Sv. Given the spacing between the continents and the small variability of the southern winds with longitude, one may assume that 9 Sv of the total 29 Sv enters the Atlantic and the other 20 Sv enters the combined Pacific–Indian Ocean system, which is also in agreement with the quasi-island calculation. These agreements indicate that the assumptions made in the earlier studies regarding the Bering Strait are probably valid.
The birth of time

The formulation of the second law of thermodynamics in the frame of general relativity is reconsidered in the case of an istotropic homogeneous universe. We show that there appears then a direct link between the cosmological state of the universe, as expressed in terms of conformal coordinates, and quantities such as energy density, pressure, and entropy associated with the description of nature. In the early universe there appears a kind of phase transition due to transfer of gravitational energy to matter associated with the cosmological expansion if the universe starts with a non-Euclidian (space) state. As a result, we may envisage the possibility of a “cold big-bang model,” in which the universe would start at zero temperature and entropy. The temperature goes then through a maximum before entering the present area of cooling related to adiabatic expansion.
Finding a long directed cycle

Consider a digraph with n vertices. For any fixed value k, we present linear- and almost-linear-time algorithms to find a cycle of length ≥ k, if one exists. We also find a cycle that has length ≥ log n/log log n in polynomial time, if one exists. Under an appropriate complexity assumption it is known to be impossible to improve this guarantee by more than a log log n factor. Our approach is based on depth-first search.
Graph cohomology and Kontsevich cycles

Abstract We use the duality between compactly supported cohomology of the associative graph complex and the cohomology of the mapping class group to show that the duals of the Kontsevich cycles [Wλ] correspond to polynomials in the Miller–Morita–Mumford classes. We also compute the coefficients of the first two terms of this polynomial. This extends the results of (Combinatorial Miller–Morita–Mumford classes and Witten cycles, math.GT/0207042, 2002), giving a more detailed answer to a question of Kontsevich (Commun. Math. Phys. 147(1) (1992) 1) and verifying more of the conjectured formulas of Arbarello and Cornalba (J. Algebraic Geom. 5 (1996) 705).
The Law of Duress and the Economics of Credible Threats

Abstract This paper argues that enforcement of an agreement, reached under a threat to refrain from dealing, should be conditioned solely on the threat's credibility. When a credible threat exists, enforcement promotes social welfare and the threatened party's interests. If agreements backed by credible threats were not enforceable, the threatening party would not extort them and would instead refrain from dealing—to the threatened party's detriment. The doctrine of duress, which invalidates such agreements, hurts the coerced party. By denying enforcement when a credible threat exists, the duress doctrine precludes the threatened party from making the commitment necessary to reach agreement. Paradoxically, the duress doctrine renders performance less likely, thereby reducing incentives to invest. The paper suggests that courts should replace the duress methodology with a credibility inquiry. It discusses factors that would be relevant under such an inquiry. Finally, it demonstrates applications of this ap...
Selective Inhibition of Tumor Oncogenes by Disruption of Super-Enhancers

Chromatin regulators have become attractive targets for cancer therapy, but it is unclear why inhibition of these ubiquitous regulators should have gene-specific effects in tumor cells. Here, we investigate how inhibition of the widely expressed transcriptional coactivator BRD4 leads to selective inhibition of the MYC oncogene in multiple myeloma (MM). BRD4 and Mediator were found to co-occupy thousands of enhancers associated with active genes. They also co-occupied a small set of exceptionally large super-enhancers associated with genes that feature prominently in MM biology, including the MYC oncogene. Treatment of MM tumor cells with the BET-bromodomain inhibitor JQ1 led to preferential loss of BRD4 at super-enhancers and consequent transcription elongation defects that preferentially impacted genes with super-enhancers, including MYC. Super-enhancers were found at key oncogenic drivers in many other tumor cells. These observations have implications for the discovery of cancer therapeutics directed at components of super-enhancers in diverse tumor types.
Two dimensional twisted chiral fermions on the lattice

Abstract It is shown that the lattice overlap correctly reproduces the chiral determinat on a two dimensional torus in the presence of nontrivial background Polyakov loop variables.
Detección de enterovirus mediante transcripción reversa y reacción de polimerasa en cadena en líquido cefalorraquídeo de niños con meningitis aséptica

Los enterovirus causan cerca de 90% de las meningitis asepticas (MA). La ausencia de un buen metodo de diagnostico etiologico determina con frecuencia tratamientos innecesarios. En este estudio se comparo la deteccion de enterovirus en liquido cefalorraquideo (LCR) usando cultivos celulares e inmunofluorescencia indirecta (CC/IFI), con la reaccion de polimerasa en cadena (RT-PCR). Se estudiaron 22 muestras de LCR provenientes de ninos con MA (casos) y 17 de ninos con otras patologias (controles). Todos fueron atendidos en servicios pediatricos del Hospital Carlos van Buren de Valparaiso. Hubo 100% de concordancia entre ambos metodos en los 22 ninos con MA, encontrandose 21 casos positivos para enterovirus. Entre los 17 controles, 2 muestras resultaron positivas por RT-PCR y una de ellas lo fue tambien por CC-IFI. La RT-PCR resulto un metodo sensible y especifico. Considerando la rapidez con que se pueden tener los resultados es esperable que su uso rutinario sea beneficioso para los pacientes con MA.
Collaborative downloading in VANET using Network Coding

Data downloading on the fly is the base of commercial data services in vehicular networks, such as office-on-wheels and entertainment-on-wheels. Due to the sparse special distribution of roadside Base Stations (BS) along the road, downloading through Roadside-to-Vehicle (R2V) connections is intermittent. When multiple vehicles with geographical proximity have a common interest in certain objects to download, they can collaborate to significantly reduce their overall download time. In this paper, we investigate the application of Network Coding (NC) in collaborative downloading (CD). We focus on the R2V part of CD, and analytically derive probability distribution and the expected value of the amount of time necessary to deliver all of the information to the vehicles with and without NC. Our results show that using NC slightly improves the downloading time in addition to removing the need for having any sort of uplink communications from vehicles to the infrastructure.
Avalanche Localization and Its Effects in Proportional Counters

Avalanche development around the anode wire in a gas proportional counter is investigated. In the region of proportional gas amplification, the avalanche is found to be well localized on one side of the anode wire, where the electrons arrive along the field lines from the point of primary ionization. Induced signals on electrodes surrounding the anode wire are used to measure the azimuthal position of the avalanche on the anode wire. Practical applications of the phenomena such as left-right assignment in drift chambers and measurement of the angular direction of the primary ionization electrons drifting towards the anode wire are discussed.
Synthesis and structure of β-Ca3Ga2N4, a ternary nitride with two interpenetrating three dimensional nets

Abstract We report the structure of a second polymorph of the ternary calcium gallium nitride Ca 3 Ga 2 N 4 , synthesized as crystals from the elements in sealed niobium tubes at 760°C using a Na/Ca melt as the growth medium. The material is an almost colorless transparent insulator. β-Ca 3 Ga 2 N 4 crystallizes in I 4 1 /acd (No. 142) with a = b =11.210(1) A, c =15.914(2) A and Z =16. It contains a pair of identical, independent interpenetrating networks based on corner sharing GaN 4 tetrahedra, which may be designated 3 ∞ [[Ga 4 N 6 ]N 4/2 ] and are related to the 3 ∞ [[Si]N 4/2 ] framework in β-cristobalite.
The Role of Hatcheries in Ensuring Social and Economic Benefits of Fisheries in the United States

Fish and fishing are woven into the fabric of American culture and deliver numerous social and economic benefits. Natural fisheries are the foundation for providing fish and fishing benefits, but a...
FORMATION AND USE OF BORON SULFONATES

Abstract Boric acid reacts swiftly with p-toluenesulfonyl chloride idine-d 5 to form the unstable boron sulfonate which is observed IR. The utility of this reaction is discussed.
The thermal history of equilibrated ordinary chondrites and the relationship between textural maturity and temperature

The compositions and textures of phases in eleven equilibrated ordinary chondrites from the H, L, and LL groups spanning petrographic types 4–6 were studied and used to constrain the thermal histories of their parent bodies. Based on Fe–Mg exchange between olivine and spinel, average equilibration temperatures for type 4–6 chondrites encompass a small range, 586–777 °C, relative to what is commonly assumed for peak temperatures (600–950 °C). The maximum temperatures recorded by individual chondrites, which are minima relative to peak metamorphic temperatures, increase subtly but systematically with metamorphic type and are tightly clustered for H4-6 (733–754 °C) and LL4-6 (670–777 °C). For the Ls, Ausson (L5) records a higher maximum olivine–spinel temperature (761 °C) than does the L4 chondrite Saratov (673 °C) or the L6 chondrite Glatton (712 °C). Our data combined with olivine–spinel equilibration temperatures calculated for other equilibrated ordinary chondrites using mineral compositions from the literature demonstrate that, in general, type 4 chondrites within each chemical group record temperatures lower than or equal to those of types 5–6 chondrites. For H chondrites, the olivine–spinel closure temperature is a function of spinel grain size, such that larger grains, abundant in types 5–6 chondrites, record temperatures of ∼740 °C or more while smaller grains, rare in types 5–6 but abundant in type 4 chondrites, record lower temperatures. Olivine–spinel temperatures in the type 6 chondrites Guarena and Glatton are consistent with rapid (50–100 °C/Myr) cooling from high temperatures in the ordinary chondrite parent bodies. With one exception (∼500 °C/Myr), olivine–spinel data for St.-Severin (LL6) are consistent with similar cooling rates. Cooling rates of order 100 °C/Myr at ∼750 °C for type 6 chondrites are considerably higher than previously determined cooling rates for lower temperatures (⩽550 °C) based on metallography, fission tracks, and geochronology. For H chondrites, current thermal models of an “onion shell” parent body are inconsistent with a small range of peak temperatures based on olivine–spinel and two pyroxene thermometry combined with a wide dispersion of cooling rates at low temperatures. Equilibrated chondrites may have sampled regions near a major transition in physical properties such as near the base of a regolith pile.