cssi/SciSciGPT-SciSciNet huggingface dataset:
Amplifying Ribbon Extensometer for Measuring Film and Fabric Strain

Variations of a low-cost amplifying linear threshold extensometer are presented in detail for high or low strain applications. Derivations of scale relationships and extraction forces are included with experimental correlations and analyses given on performance, attachment problems, gain selection, gage and base material compatibility, and zero setting techniques. Flight applications of unamplified gages on parawing deployment tests are noted. The amplified gages perform accurately in laboratory tests and further experience is needed on performance under dynamic environments.
Spatial Structure of the Cooper Pair

The Cooper pair is generally analyzed in momentum space, but its real-space structure also follows directly from the Bardeen–Cooper–Schrieffer (BCS) theory. It is shown here that this leads to a spherically symmetrical quasi-atomic wavefunction, with an identical “onion-like" layered structure for each of the electrons constituting the Cooper pair, with charge layers ∼0.1 nm and radius ∼100 nm for a classic BCS superconductor. This charge modulation induces a corresponding charge modulation in the background ionic lattice, and the attractive interaction between these two opposite charge modulations produces the binding energy of the Cooper pair. This physically based interaction potential is similar to that in the simple BCS approximation. The implications of this real-space picture for understanding conventional and exotic superconductors are discussed.
Inflation and Stock Prices: No Illusion

Campbell and Vuolteenaho (2004) use VAR results to advocate inflation illusion as the explanation for the positive association between inflation and dividend yields. Using a structural approach, we find that a fully rational dynamic general equilibrium model can generate a positive correlation between dividend yields and inflation as observed in the data. The paper describes a channel by which the technology shock moves both inflation and dividend yields in the same direction, resulting in a positive correlation between the two.
Preparation of L-(phosphonodifluoromethyl)phenylalanine derivatives as non-hydrolyzable mimetics of O-phosphotyrosine

Abstract N-t-BOC-L-(Phosphonodifluoromethyl)phenylalanine benzyl ester ( 1 ) was prepared in 5 steps from N-t-BOC-L-tyrosine benzyl eser O-triflate ( 4 ). Compound 1 was further converted to derivatives 2 and 3 which are potentially suitable for peptide synthesis. Analogs 1 - 3 are non-hydrolyzable mimetics of O-phosphotyrosine.
Calogero–Moser spaces over algebraic curves

In these notes, we give a survey of the main results of [5] and [7]. Our aim is to generalize the geometric classification of (left) ideals of the first Weyl algebra \({A_{1}(\mathbb{C})}\) (see [8, 9]) to the ring \({\mathcal{D}}(X)\) of differential operators on an arbitrary complex smooth affine curve X. We approach this problem in two steps: first, we classify the ideals of \({\mathcal{D}}(X)\) up to stable isomorphism, in terms of the Picard group of X; then, we refine this classification by describing each stable isomorphism class as a disjoint union of (quotients of) generalized Calogero–Moser spaces \({\mathcal{C}}_{n}(X,{\mathcal{I}})\). The latter are defined as representation varieties of deformed preprojective algebras over a certain noncommutative extension of the ring of regular functions on X. As in the classical case, \({\mathcal{C}}_{n}(X,{\mathcal{I}})\) turn out to be smooth irreducible varieties of dimension 2n.
A semiconductor bulk material that emits direct white light.

A unique type of inorganic−organic hybrid semiconductor bulk material is capable of emitting direct white light. Their photoluminescence properties can be tuned precisely and systematically by modifying structures and composition. They could be used as a single-material light-emitting source in high efficiency white-light-emitting diodes.
Human factors evaluation of two data base query languages: square and sequel

Boyce et al. have recently described two data base query languages, SQUARE and SEQUEL, which are intended for use in an interactive mode by both programmers and professional non-programmers (e.g., accountants, lawyers, managers). The languages are comparable in the sense that the basic operators, underlying data structures and intended use are the same. They differ primarily in syntactic form, with a few additional differences in some of the specific features. Both of the languages are intended to be easily learned and used by people without specialized computer training.
Treating minority patients with depression and anxiety: what does the evidence tell us?

Objective: The purpose of this study is to examine the current state of knowledge regarding treating ethnic/racial minority patients with mood and anxiety disorders, emphasizing data-based studies whenever possible. Method: This article reviews the evidence on poorer access and quality of care for minorities, the biological and cultural differences between minority and majority populations that may impact care and outcomes, and recent studies that address minority treatment response and outcomes both alone and in comparison to majority groups. Results: Numerous impediments to appropriately treating anxious and depressed minority patients remain. Underutilization and poor quality of mental health care in minorities is due to less-than-favorable illness and treatment beliefs that affect adherence and outcome, stigma, clinician failure to engage the patient, poor patient activation and biological differences that may impact pharmacotherapy choice. However, though limited in number, some studies do indicate that when appropriate treatment is well-delivered to minorities, results are comparable to those seen among Caucasian patients. Conclusions: The clinician treating members of minority groups must consider differential personal elements, from the biological to the cultural, to achieve treatment success. The limited available data do suggest that minority patients can be successfully treated with available interventions. Of primary importance is for researchers to increase the number of carefully designed intervention studies that allow for ethnic/ racial minority-specific analyses.
Vancomycin, teicoplanin, and ramoplanin: synthetic and mechanistic studies.

Vancomycin, teicoplanin, and ramoplanin are potent glycopeptide antibiotics that act by inhibiting bacterial cell wall biosynthesis. The former are used clinically as the antibiotics of last resort for the treatment of methicillin-resistant Staphylococcus aureus and the latter is a promising new antibiotic that is not susceptible to the emerging bacterial resistance to vancomycin and teicoplanin. A summary of our recent total synthesis of the vancomycin aglycon, our first and second generation total syntheses of the teicoplanin aglycon, and our progress on the total synthesis of the ramoplanins is presented. This work lays the foundation for ongoing structure-function studies on the antibiotics that may clarify or define their site and mechanism of action leading to the development of improved or reengineered antibiotics.
Regimes of Traction in Concentrated Contact Lubrication

Experimental evidence is presented for the existence of three regimes of traction in concentrated contacts. Data are obtained in a rolling contact simulator by varying the lubricant, temperature, rolling speed, load and surface roughness at a fixed slide-to-roll ratio. At lower thicknesses the mixed regime is encountered, and traction is increased due to asperity interaction, while at higher film thicknesses, the lubricant pressure is distributed over a greater area than the Hertzian region, resulting in a lower average pressure and reduced traction.
Information technology and the rise of household bankruptcy

Abstract Several studies have attributed the rise of household bankruptcy in the past two decades to the decline of social stigma associated with default. Stigma explanations, however, cannot account for the large increase in the use of unsecured credit during this period. I explain the simultaneous increase in bankruptcy rates and unsecured credit as the result of improvements in credit-rating technologies. Using an environment where borrowers face heterogeneous default costs (unobservable by creditors), I show that such improvements will lead to agents with high default costs, i.e., “safe” borrowers, being able to borrow more. A quantitative example illustrates that this increased access to credit can be large enough to raise both equilibrium borrowing and default rates.
Stability of time reversed waves in changing media

We analyze the refocusing properties of time reversed waves that propagate in two different media during the forward and backward stages of a time-reversal experiment. We consider two regimes of wave propagation modeled by the paraxial wave equation with a smooth random refraction coefficient and the Ito-Schrodinger equation, respectively. In both regimes, we rigorously characterize the refocused signal in the high frequency limit and show that it is statistically stable, that is, independent of the realizations of the two media. The analysis is based on a characterization of the high frequency limit of the Wigner transform of two fields propagating in different media. The refocusing quality of the backpropagated signal is determined by the cross correlation of the two media. When the two media decorrelate, two distinct de-focusing effects are observed. The first one is a purely absorbing effect due to the loss of coherence at a fixed frequency. The second one is a phase modulation effect of the refocused signal at each frequency. This causes de-focusing of the backpropagated signal in the time domain.
Modifying lines-of-flight in the planning process for improved maintenance robustness

As a part of their planning process, airlines construct lines-of-flight (LOFs ) - daily repeating sequences of flights, each of which will be flown by a single aircraft. In the week leading up to the actual day-of-operations, these LOFs are then assigned to specific aircraft (tails), forming multi-day aircraft routings that in turn enable the scheduling of routine maintenance checks. Operational disruptions, however, can lead to deviations from these routings, which in turn disrupt the maintenance plan. The goal of our research is to improve the construction of LOFs so as to increase the likelihood of being able to recover from maintenance disruptions without costly over-the-day aircraft swaps. We present a new metric, maintenance reachability (MR), which measures the robustness of a planned set of LOFs, and develop a mathematical programming approach to improving the MR of a given set of LOFs. We provide computational results based on data from a major U.S. carrier demonstrating that significant improvements in MR can be achieved with only a small number of changes to the original set of LOFs. Finally, we conclude by showing that even under imperfect input data, MR can be improved relative to a planned set of LOFs.
New highly conjugated porphyrin chromophores: Synthesis of mono- and diphenanthroporphyrins

Abstract Porphyrins with one or two fused phenanthrene subunits have been prepared from phenanthro[9,10-c]pyrroles, which are in turn easily prepared from 9-nitrophenanthrene.
Stability of Binary Asteroids

The stability and final outcome of a strongly interacting binary asteroid system is considered. We discuss the implications of the system transferring energy and angular momentum between rotational and translational motion while conserving the total system energy and angular momentum. Using these results we can develop a set of sufficient conditions for stability against escape and impact. These allow us to delineate several classes of final outcomes for a binary asteroid system, each of which may have implications for asteroid observations. The effects of energy dissipation on an asteroid binary system are also considered and are shown to be able to change the stability of the system against escape and impact. An example computation for the near-Earth asteroid binary 1996 FG3 is given along with a series of numerical explorations of an evolving binary system consisting of an ellipsoid and a sphere of equal mass.
Collocative Integrity and Our Many Varied Subjects: What the Metric of Alignment between Classification Scheme and Indexer Tells Us About Langridge’s Theory of Indexing

As the universe of knowledge and subjects change over time, indexing languages like classification schemes, accommodate that change by restructuring. Restructuring indexing languages affects indexer and cataloguer work. Subjects may split or lump together. They may disappear only to reappear later. And new subjects may emerge that were assumed to be already present, but not clearly articulated (Miksa, 1998). In this context we have the complex relationship between the indexing language, the text being described, and the already described collection (Tennis, 2007). It is possible to imagine indexers placing a document into an outdated class, because it is the one they have already used for their collection. However, doing this erases the semantics in the present indexing language. Given this range of choice in the context of indexing language change, the question arises, what does this look like in practice? How often does this occur? Further, what does this phenomenon tell us about subjects in indexing languages? Does the practice we observe in the reaction to indexing language change provide us evidence of conceptual models of subjects and subject creation? If it is incomplete, but gets us close, what evidence do we still require?
First Determination of the True Mass of Coronal Mass Ejections: A Novel Approach to Using the Two STEREO Viewpoints

The twin Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) COR2 coronagraphs of the Solar Terrestrial Relations Observatory (STEREO) provide images of the solar corona from two viewpoints in the solar system. Since their launch in late 2006, the STEREO Ahead (A) and Behind (B) spacecraft have been slowly separating from Earth at a rate of 225 per year. By the end of 2007, the two spacecraft were separated by more than 40° from each other. At that time, we began to see large-scale differences in the morphology and total intensity between coronal mass ejections (CMEs) observed with SECCHI-COR2 on STEREO-A and B. Due to the effects of the Thomson scattering geometry, the intensity of an observed CME is dependent on the angle it makes with the observed plane of the sky. From the intensity images, we can calculate the integrated line-of-sight electron density and mass. We demonstrate that it is possible to simultaneously derive the direction and true total mass of the CME if we make the simple assumption that the same mass should be observed in COR2-A and B.
I get by with a little help from my cyber-friends: Sharing stories of good and bad times on the web

Although the use of the World Wide Web has expanded tremendously in the past few years, we still know very little about how users are working with this new medium, what they attempt to accomplish, what works, what doesn’ t. One way to answer such questions is to simply ask users for descriptions of their own activities. This paper presents an analysis of 133 stories of Web use contributed by users over a period of 40 months, since the Web Storybase began operation in December 1994. Usage of the Storybase is examined in general, and the stories are analyzed along several dimensions. The stories convey usage experiences that not only involve global information retrieval and person-to-person contact, but also the development of both good and bad interpersonal relationships, as well as extensive reflection on how the Web is changing our lives.
A Comparison of Experimental Rotordynamic Coefficients and Leakage Characteristics Between Hole-Pattern Gas Damper Seals and a Honeycomb Seal

Honeycomb annular seals are an attractive design alternative due to their superior static and dynamic performance. However, their implementation in industrial practice has been delayed by the following characteristics: a) manufacturing time can be appreciable, and b) they can seriously damage the shaft if rubbing occurs. To minimize these problems, hole-pattern gas damper seals, which are formed by simply drilling holes into an annular smooth seal, were manufactured and tested. The hole-pattern damper seal stator can be made of high-strength plastic materials which are less likely to damage a shaft during rubbing. The experimental results presented demonstrate that, compared to a honeycomb seal, a hole-pattern damper seal with 3.18 mm hole diameters and a high percentage of hole surface has achieved: (a) an average of 12 percent reduction in leakage rate, and (b) considerably higher effective damping, especially under high speeds and low inlet pressure ratio conditions.
Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary disease occurring in 1 in 200 to 1 in 1,000 individuals. ADPKD is characterized by cystic lesions in the kidneys and often by structural abnormalities in the gastrointestinal tract and cardiovascular system. The pathogenesis of the disorder appears to involve both cellular proliferation and altered extracellular matrix synthesis. Diagnosis can be established most readily by the sonographic demonstration of renal cysts or by gene linkage analysis. Renal manifestations of ADPKD include hypertension, infection, nephrolithiasis and malignancy. The prominent extrarenal manifestations include hepatic cysts, mitral valve prolapse and intracranial aneurysms. Although only 2% of nephrons appear to be involved in cyst formation, the renal function often slowly deteriorates. Presently, there is a 52% probability of an ADPKD subject’s being alive without renal replacement therapy at age 73. ADPKD patients with endstage renal disease respond to renal replacement therapy as well as other patient groups.
The Measurement and Control of Beta Change

Applied researchers have long been confronted with the complex statistical problems associated with the measurement of change. A method frequently used in such analyses is the pretest-posttest research design. This approach incorporates the often overlooked assumption that the pretest and posttest scores are comparable. However, for the scores to be comparable, a common metric must exist between them. Distinguishing between three types of change in test scores (alpha, beta, and gamma), we present an original statistical procedure for measuring and controlling the confounding influence of beta change — i.e., the problem of scale recalibration in the minds of respondents.
Palladium/BINAP(S)-catalyzed asymmetric allylic amination.

The enantioselective allylic amination of acyclic allylic carbonates catalyzed by a palladium/(S)-BINAP(S) system was investigated. Amination of several substrates proceeded with high ee. Crotyl carbonates show an unusually high regioselectivity for the branched isomer. The use of (S)-TolBINAP(S) and (S)-3,5-xylyl-BINAP(S) as ligands was found to increase the enantioselectivity of the aminations. A P,S binding mode of the BINAP(S) ligand was found in an X-ray crystallographic study.
Functional consequences of the somatopause and its treatment.

The decline in the function of the growth hormone-releasing hormone, growth hormone, insulin-like growth factor (GHRH-GH-IGF) axis has been termed the somatopause. Many of the catabolic sequelae seen in normal aging has been attributed to this decrease in circulating GH and IGF-I. In order to provide hormone replacement therapy for the somatopause, elderly subjects have been treated with GH, IGF-I, or both hormones together. Whereas numerous beneficial effects on body composition, strength, and quality of life have been reported in some studies, other studies have reported only marginal functional imporvements. Moreover, it is clear that both hormones can cause significant morbidity.
Inertial Particle Dynamics in a Hurricane

Abstract The motion of inertial (i.e., finite-size) particles is analyzed in a three-dimensional unsteady simulation of Hurricane Isabel. As established recently, the long-term dynamics of inertial particles in a fluid is governed by a reduced-order inertial equation, obtained as a small perturbation of passive fluid advection on a globally attracting slow manifold in the phase space of particle motions. Use of the inertial equation enables the visualization of three-dimensional inertial Lagrangian coherent structures (ILCS) on the slow manifold. These ILCS govern the asymptotic behavior of finite-size particles within a hurricane. A comparison of the attracting ILCS with conventional Eulerian fields reveals the Lagrangian footprint of the hurricane eyewall and of a large rainband. By contrast, repelling ILCS within the eye region admit a more complex geometry that cannot be compared directly with Eulerian features.
Geothermal resources assessment in Hawaii

Report prepared for Western States Cooperative Direct Heat Resource Assessment under grant No. DOE DE-ACO3-80SF10819, Feb. 1985.
Critical Ising on the Square Lattice Mixes in Polynomial Time

The Ising model is widely regarded as the most studied model of spin-systems in statistical physics. The focus of this paper is its dynamic (stochastic) version, the Glauber dynamics, introduced in 1963 and by now the most popular means of sampling the Ising measure. Intensive study throughout the last three decades has yielded a rigorous understanding of the spectral-gap of the dynamics on \({\mathbb{Z}^2}\) everywhere except at criticality. While the critical behavior of the Ising model has long been the focus for physicists, mathematicians have only recently developed an understanding of its critical geometry with the advent of SLE, CLE and new tools to study conformally invariant systems.
The use of phosphonitrilic dichloride cyclic trimer in oligopeptide synthesis. Synthesis of isoxazolyl-prodrugs of netropsin and distamycin

Phosphonitrilic dichloride cyclic trimer has been found to be an effective activating agent for the synthesis of oligopeptides containing N-terminal isoxazole-4-carboxamide groups
A probabilistic theory of random maps

Abstract We present a probabilistic theory of random maps with discrete time and continuous state. The forward and backward Kolmogorov equations as well as the FPK equation governing the evolution of the probability density function of the system are derived. The moment equations of arbitrary order are derived, and the reliability and first passage time problem are also studied. Examples are presented to demonstrate the application of the theoretical development. Numerical solutions including the time histories of moment evolution, steady state probability density function, reliability and first passage time probability density function for time discrete random maps are included. The present work compliments the existing theory of continuous time stochastic processes.
Dimensional Power Counting in Nuclei

Weinberg's dimensional power counting for nuclei is reprised in this primer. The role of QCD and chiral symmetry in constructing effective Lagrangians is discussed. The two-scale hypothesis of Manohar and Georgi is combined with power counting in amplitudes to shed light on the scales of nuclear kinetic and potential energies, the size of strong-interaction coupling constants, the size of meson-exchange currents, and the relative sizes of many-nucleon forces. Numerous examples are worked out and compared to conventional nuclear models.
Testing the generalizability of a career commitment measure and its impact on employee turnover.

Abstract Using a longitudinally tracked sample of 133 full-time bank tellers from a large bank, this study tested the generalizability of a career commitment measure and its impact on emplyee turnover. The results indicated that career commitment could be reliably operationalized and was distinct from job involvement and organizational commitment. Additional evidence for the convergent and discriminant validity of career commitment was also found. Career commitment was found to be significantly negatively related to turnover; however, this relationship was mediated by career withdrawal cognitions. Findings are discussed in terms of identifying the threshold level for operationalizing career commitment and the need for future research on career change.
Ring expansion of alkynyl cyclopropanes to highly substituted cyclobutenes via a N-sulfonyl-1,2,3-triazole intermediate

Regioselective ring expansion of alkynyl cyclopropanes to highly substituted cyclobutenes was developed. The reaction involves a copper-catalyzed cycloaddition of an alkyne with an arylsulfonyl azide and a silver-catalyzed carbene formation followed by ring expansion of a cyclopropyl carbene intermediate.
Rapid High Temperature Solar Thermal Biomass Gasification in a Prototype Cavity Reactor

High temperature biomass gasification has been performed in a prototype concentrated solar reactor. Gasification of biomass at high temperatures has many advantages compared with historical methods of producing fuels. Enhancements in overall conversion, product composition ratios, and tar reduction are achievable at temperatures greater than 1000°C. Furthermore, the utilization of concentrated solar energy to drive these reactions eliminates the need to consume a portion of the product stream for heating and some of the solar energy is stored as chemical energy in the product stream. Experiments to determine the effects of temperature, gas flow rate, and feed type were conducted at the high flux solar furnace at the National Renewable Energy Laboratory, Golden, CO. These experiments were conducted in a reflective cavity multitube prototype reactor. Biomass type was found to be the only significant factor within a 95% confidence interval. Biomass conversion as high as 68% was achieved on sun. Construction and design considerations of the prototype reactor are discussed as well as initial performance results.
A one-loop test of string duality

Abstract We test Type IIA-heterotic string duality in six dimensions by showing that the sigma model anomaly of the heterotic string is generated by a combination of a tree level and a string one-loop correction on the Type IIA side.
On the Apparent Orbital Inclination Change of the Extrasolar Transiting Planet TrES-2b

On 2009 June 15 UT the transit of TrES-2b was detected using the University of Arizona's 1.55 m Kuiper Telescope with 2.0-2.5 millimag rms accuracy in the I band. We find a central transit time of Tc = 2454997.76286 ± 0.00035 HJD, an orbital period of P = 2.4706127 ± 0.0000009 days, and an inclination angle of i = 8392 ± 0°.05, which is consistent with our re-fit of the original I-band light curve of O'Donovan et al. where we find i = 8384 ± 0°.05. We calculate an insignificant inclination change of Δi = –008 ± 0°.07 over the last three years, and as such, our observations rule out, at the ~11σ level, the apparent change of orbital inclination to i predicted = 8335 ± 0°.1 as predicted by Mislis & Schmitt and Mislis et al. for our epoch. Moreover, our analysis of a recently published Kepler Space Telescope light curve for TrES-2b finds an inclination of i = 8391 ± 003 for a similar epoch. These Kepler results definitively rule out change in i as a function of time. Indeed, we detect no significant changes in any of the orbital parameters of TrES-2b.
A short proof of rigidity of convex polytopes.

We present a much simplified proof of Dehn’s theorem on the infinitesimal rigidity of convex polytopes. Our approach is based on the ideas of Trushkina [1] and Schramm [2].
Resonance transition 795-nm rubidium laser using 3He buffer gas

Abstract We report a demonstration of a 795-nm rubidium optical resonance transition laser using a buffer gas consisting of pure 3 He. This follows our recent demonstration of a hydrocarbon-free 795-nm rubidium resonance laser which used naturally-occurring He as the buffer gas. Using He gas that is isotopically enriched with 3 He yields enhanced mixing of the Rb fine-structure levels. This enables efficient lasing at reduced He buffer gas pressure, improved thermal management in high average power Rb lasers and enhanced power scaling potential of such systems.
Time-optimal slewing of flexible spacecraft

The tune optimal slewing problem of flexible spacecraft is considered. The system is discretized by the assumed modes method, and the problem is solved for a linearized model in reduced state space by parameter optimization. Optimality is verified by the maximal principle. The linear solution is further used to obtain time optimal solutions for the non-linear problem.
Graphs Whose Edge Set Can Be Partitioned into Maximum Matchings

This paper provides structural characterization of simple graphs whose edge set can be partitioned into maximum matchings. We use Vizing's classification of simple graphs based on edge chromatic index.
An Inherited Efficiencies Model of Non-Genomic Evolution

Abstract A model for the evolution of biological systems in the absence of a nucleic acid-like genome is proposed and applied to model the earliest living organisms – protocells composed of membrane encapsulated peptides. Assuming that the peptides can make and break bonds between amino acids, and bonds in non-functional peptides are more likely to be destroyed than in functional peptides, it is demonstrated that the catalytic capabilities of the system as a whole can increase. This increase is defined to be non-genomic evolution. The relationship between the proposed mechanism for evolution and recent experiments on self-replicating peptides is discussed.
Operations control with an electronic computer

I consider it a great privilege to participate in the discussions of this conference. I can think of no more timely panel topic than the Role of Computers in Business. We are all familiar with the enormous impact that computers are having on industry today, and the promising future for computers that lies directly ahead. I believe we should face this dynamic situation with full realization of both the potentialities and the difficulties that confront us.
Coherent image fringe contrast measurement with sensing arrays

Two methods are described for measuring interferometric fringe contrast with sensing arrays. The absence of air turbulence allows contrast to be determined quickly by measuring the intensity of the fringe pattern at phases 90° apart. The presence of turbulence requires that the peak-to-peak fringe intensity be found by sampling the fringes as they are scanned across the array. An analysis is presented showing the relation between maximum error in fringe contrast measurement and the number of samples taken. Experimental results are presented which show the effect of turbulence on fringe contrast measurement.
Blocking for external graph searching

In this paper we consider the problem of using disk blocks efficiently in searching graphs that are too large to fit in internal memory. Our model allows a vertex to be represented any number of times on the disk in order to take advantage of redundancy. We give matching upper and lower bounds for completed-ary trees andd-dimensional grid graphs, as well as for classes of general graphs that intuitively speaking have a close to uniform number of neighbors around each vertex. We also show that, for the special case of grid graphs blocked with isothetic hypercubes, there is a provably better speed-up if even a small amount of redundancy is permitted.
Efficient job scheduling algorithms with multi-type contentions

In this paper, we consider an interesting generalization of the classic job scheduling problem in which each job needs to compete not only for machines but also for other types of resources. The contentions among jobs for machines and for resources could interfere with each other, which complicates the problem dramatically. We present a family of approximation algorithms for solving several variants of the problem by using a generic algorithmic framework. Our algorithms achieve a constant approximation ratio (i.e., 3) when there is only one type of resources or certain dependency relation exists among multiple types of resources. When the r resources are unrelated, the approximation ratio of our algorithm becomes k+2, where k≤ r is a constant depending on the problem instance. As an application, we also show that our techniques can be easily applied to optical burst switching (OBS) networks to design more efficient wavelength scheduling algorithms.
Characterizing Paretian preferences

A characterization of a property of binary relations is of type M if it can be stated in terms of ordered M-tuples of alternatives. A characterization of finite type provides an easy test of whether preferences over a large set of alternatives possesses the property characterized. Unfortunately, there is no characterization of finite type for Pareto representability in $${\Re }^{2}$$ . A partial result along the same lines is obtained for Pareto representability in $${\Re }^{k}$$ , k>2.
An alternative method for predicting size of femoral component of Oxford partial knee replacement

Abstract Background No direct intra-operative measurement to determine the ideal size of the femoral component of Oxford unicompartmental knee replacement (UKR) is currently present. The aim of this study is to assess the accuracy of patients' shoe size as a predictor of femoral component size. Methods A retrospective study was conducted to identify the correlation between patients' shoe size (British system) and the femoral component size. After excluding patients who died ( n = 2) and patients in whom the implanted femoral component size was inaccurate ( n = 13), the remaining cases (93 UKR in 88 patients) formed the study sample. Postoperative radiographs were reviewed to determine femoral component fit. Results We found positive correlation between shoe size and femoral component size. In females; a shoe size from 2.5 to 6 predicted a small femoral component and shoe size from 6.5 to 8.0 predicted a medium femoral component. In males, a shoe size from 6 to 9.5 predicted a medium femoral component and a shoe size from 10 to 13 predicted a large femoral component. This relation predicted the femoral component size accurately in 80% of cases. A subgroup analysis, after excluding patients who changed their shoe size during adulthood after foot surgery or pathology ( n = 20), showed an accuracy rate of 81%. Conclusion Shoe size is a simple method that predicts femoral component size more accurately than other methods currently used such as templating, tibial component size and height based on gender.
Regiospecific syntheses of functionalized diaryliodonium tosylates via [hydroxy(tosyloxy)iodo]arenes generated in situ from (diacetoxyiodo)arenes.

Ready access to 18F-labeled aryl synthons is required for preparing novel radiotracers for molecular imaging with positron emission tomography. Diaryliodonium salts react with cyclotron-produced no-carrier-added [18F]fluoride ion to produce [18F]aryl fluorides. We aimed to prepare functionalized diaryliodonium salts to serve as potential precursors for producing useful 18F-labeled aryl synthons, such as 18F-labeled halomethylbenzenes, benzaldehydes, and benzoic acid esters. Such salts were designed to have one functionalized aryl ring, one relatively electron-rich ring, such as 4-methoxyphenyl or 2-thienyl, and a nonfluorine containing weakly nucleophilic anion. Generation of a [hydroxy(tosyloxy)iodo]arene from a functionalized (diacetoxyiodo)arene in situ followed by treatment with an electron-rich arene, such as anisole or thiophene, or with a functionalized arylstannane gave expedient regiospecific access to a wide range of functionally diverse diaryliodonium tosylates in moderate to high yields (44–98...
Electronic states and geometries of small Be clusters

Ab initio calculations were carried out on all regular geometric configurations of beryllium clusters containing three through seven atoms. Restricted Hartree–Fock, unrestricted Hartree–Fock, and fourth‐order Mo/ller–Plesset perturbation theory (MP4) using a 6‐31G basis set were used to study singlet, triplet, and quintet spin states of each cluster. The septet state of the most stable nuclear configuration of Be7 was also examined using unrestricted Hartree–Fock theory. In addition, Be4 was examined as a prototype for larger clusters, for which accurate calculations may not be computationally feasible. The most stable symmetric nuclear configuration and electronic state of Be4 was determined at increasingly improved levels of approximation. Hartree–Fock, configuration interaction, and Mo/ller–Plesset perturbation theory calculations were carried out using 6‐31G, 6‐311G, 6‐31G*, and 6‐311G* basis sets. Binding energies for the most stable configuration of each cluster were improved by MP4 calculations in ...
Sensor-based exploration for convex bodies: a new roadmap for a convex-shaped robot

We present a new roadmap that can be used to guide a convex body to explore an unknown planar workspace, i.e., to map an unknown configuration space diffeomorphic to SE(2). This new roadmap is called the convex hierarchical generalized Voronoi graph (convex-HGVG). Since this roadmap is defined in terms of workspace distance information that is within line of sight of the convex body, we can use it to direct the robot to explore an unknown configuration space diffeomorphic to SE(2). The challenge in defining the roadmap is that SE(2), with holes removed from it, generally does not have a one-dimensional deformation retract. Therefore, we decompose the punctured SE (2) into contractible regions, in which we define convex generalized Voronoi graphs (convex-GVG), and then connect these graphs with additional structures called convex-R edges. We formally show that the convex-HGVG, which is the union of the convex-GVG edges and the convex-R edges, is indeed a roadmap.
p2-Cycles: p-Cycles with parasitic protection links☆

Abstract The p -cycle and its Failure Independent Path Protection (FIPP) extension are known to be efficient and agile protection strategies. The p -cycle is pre-configured such that if there is a failure, only the switches at two end nodes need to be reconfigured. In this paper, we extend the p -cycle by allowing cycles to have attached links, called Parasitic Protection Links (PPL), in order to protect paths whose source and destination nodes are not only located on the cycle but also connected by a PPL to the cycle. A p -cycle with PPL is named p 2 -cycle. We address the unicast service protection problem against single-link failures by using p 2 -cycle in mesh networks for both static and dynamic traffic scenarios. In the static case, the problem is formulated as an Integer Linear Program (ILP). We further propose two p 2 -cycle based heuristic algorithms, Strict Routing Protection (SRP) and Flexible Routing Protection (FRP), to address the dynamic traffic case. The numerical results show that the p 2 -cycle scheme provides better capacity efficiency than the FIPP p -cycle scheme in all the traffic scenarios considered and achieves only less than 1% extra total cost over the optimum in COST239, provided by Shared Backup Path Protection (SBPP) approach when the traffic load is high. We also study the failure recovery performance in terms of average number of switch reconfigurations (NOR), and show that the performance of the p 2 -cycle becomes much better than that of SBPP and gets close to FIPP as the traffic demand increases. In the dynamic case, both SRP and FRP outperform FIPP p -cycle schemes in terms of blocking probability in most scenarios considered. In general, the p 2 -cycle protection scheme outperforms the p -cycle based in terms of capacity efficiencies which being slightly slower in terms of traffic recovery speed.
The Responsiveness of Consumer Prices to Exchange Rates: A Synthesis Of Some New Open Economy Macro Models

General equilibrium optimizing models with sticky nominal prices allow us to revisit questions about optimal monetary policy in open economies. If nominal prices are set in producers’ currencies, appropriate monetary policy can reproduce the allocations under flexible prices. If nominal prices are set in consumers’ currencies, stable nominal exchange rates may be desirable. In this case, a nominal exchange rate fixed at the purchasing power parity level can have desirable consequences for risk sharing, and nominal exchange rate flexibility cannot deliver optimal relative price changes. However, evidence shows that pass–through may be greater to import prices than to consumer prices. If prices are fixed for consumers, but importer–distributors face pass–through, then monetary policy–makers face a trade–off that might require some control of nominal exchange rates, but not purely fixed rates.
Do as you say, say as you do: evidence on gender differences in actual and stated contributions to public goods

Abstract Recent work on public goods contributions has examined the relationship between gender and free-riding behavior in studies using laboratory public goods. This research furthers this line of inquiry by examining gender as a possible explanation of hypothetical bias, which occurs in valuation studies using real world public goods. Results show that gender differences exist in hypothetical valuation exercises, but not in real valuation exercises. Further, the results show that hypothetical bias is almost three times larger for males than for females, an important result for researchers investigating the source of, and solutions for, hypothetical bias.
Rank two vector bundles with canonical determinant

Denote by Bk2,K the locus of vector bundles of rank two that have canonical determinant and at least k sections. We show that for a generic curve of genus g,Bk2,K is non-empty and has a component of the expected dimension if g is sufficiently large. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
The spread of attention across features of a surface

Contrasting theories of visual attention have emphasized selection by spatial location, individual features, and whole objects. We used functional magnetic resonance imaging to ask whether and how attention to one feature of an object spreads to other features of the same object. Subjects viewed two spatially superimposed surfaces of random dots that were segregated by distinct color-motion conjunctions. The color and direction of motion of each surface changed smoothly and in a cyclical fashion. Subjects were required to track one feature (e.g., color) of one of the two surfaces and detect brief moments when the attended feature diverged from its smooth trajectory. To tease apart the effect of attention to individual features on the hemodynamic response, we used a frequency-tagging scheme. In this scheme, the stimulus features (color and direction of motion) are modulated periodically at distinct frequencies so that the contribution of each feature to the hemodynamics can be inferred from the harmonic response at the corresponding frequency. We found that attention to one feature (e.g., color) of one surface increased the response modulation not only to the attended feature but also to the other feature (e.g., motion) of the same surface. This attentional modulation was evident in multiple visual areas and was present as early as V1. The spread of attention to the behaviorally irrelevant features of a surface suggests that attention may automatically select all features of a single object. Thus object-based attention may be supported by an enhancement of feature-specific sensory signals in the visual cortex.
Quark masses using domain wall fermions

Abstract Due to the attractive features that domain wall fermions possess with respect to chiral symmetry, we continue our investigation of the light quark masses with this discretization. Achieving reliable results, especially for (mu + md/2, requires strict control of systematic uncertainties. Our present results were obtained on a quenched β = 6.0 lattice with spatial volume ≈ (1.5 fm)3. Consequently we remark on effects of finite volume as well as finite extent in the fictitious fifth dimension. We compute the renormalization factors nonperturbatively and compare to the one-loop perturbative result.
A practical synthesis of trans-iodoolefins

Abstract Trimethylsilyl iodide was found to react smoothly with the acetylenic ketones 3 and 6 to yield the trans-β-iodovinyl ketones 4 and 7 , respectively. Hydride reduction of 4 and 7 gave the trans-iodoolefins 5 and 8 , which correspond to the C.19–C.22 and C.1–C.7 portions of the marine natural product palytoxin.
Algorithmic integrability tests for nonlinear differential and lattice equations

Abstract Three symbolic algorithms for testing the integrability of polynomial systems of partial differential and differential-difference equations are presented. The first algorithm is the well-known Painleve test, which is applicable to polynomial systems of ordinary and partial differential equations. The second and third algorithms allow one to explicitly compute polynomial conserved densities and higher-order symmetries of nonlinear evolution and lattice equations. The first algorithm is implemented in the symbolic syntax of both Macsyma and Mathematica . The second and third algorithms are available in Mathematica . The codes can be used for computer-aided integrability testing of nonlinear differential and lattice equations as they occur in various branches of the sciences and engineering. Applied to systems with parameters, the codes can determine the conditions on the parameters so that the systems pass the Painleve test, or admit a sequence of conserved densities or higher-order symmetries.
Modeling and predicting the growth and death of membership-based websites

Driven by outstanding success stories of Internet startups such as Facebook and The Huffington Post, recent studies have thoroughly described their growth. These highly visible online success stories, however, overshadow an untold number of similar ventures that fail. The study of website popularity is ultimately incomplete without general mechanisms that can describe both successes and failures. In this work we present six years of the daily number of users (DAU) of twenty-two membership-based websites - encompassing online social networks, grassroots movements, online forums, and membership-only Internet stores - well balanced between successes and failures. We then propose a combination of reaction-diffusion-decay processes whose resulting equations seem not only to describe well the observed DAU time series but also provide means to roughly predict their evolution. This model allows an approximate automatic DAU-based classification of websites into self-sustainable v.s. unsustainable and whether the startup growth is mostly driven by marketing & media campaigns or word-of-mouth adoptions.