cssi/SciSciGPT-SciSciNet huggingface dataset:
The Dynamics of Provincial Growth in China: A Nonparametric Approach

China's growth performance since the start of economic reforms in 1978 has been impressive, but the gains have not been distributed equally across provinces. We use a nonparametric approach to analyze the variation in labor productivity growth across China's provinces. This approach imposes less structure on the data than the standard growth accounting framework and allows for a breakdown of labor productivity into efficiency gains, technological progress, and capital deepening. We have the following results. First, we find that on average capital deepening accounts for about 75 percent of total labor productivity growth, while efficiency and technological improvements account for about 7 and 18 percent, respectively. Second, technical change is not neutral. Third, whereas improvement in efficiency contributes to convergence in labor productivity between provinces, technical change contributes to productivity disparity across provinces. Finally, we find that foreign direct investment has a positive and significant effect on efficiency growth and technical progress.
Interannual variability in upper ocean heat content, temperature, and thermosteric expansion on global scales

[1] Satellite altimetric height was combined with approximately 1,000,000 in situ temperature profiles to produce global estimates of upper ocean heat content, temperature, and thermosteric sea level variability on interannual timescales. Maps of these quantities from mid-1993 through mid-2003 were calculated using the technique developed by Willis et al. [2003]. The time series of globally averaged heat content contains a small amount of interannual variability and implies an oceanic warming rate of 0.86 ± 0.12 watts per square meter of ocean (0.29 ± 0.04 pW) from 1993 to 2003 for the upper 750 m of the water column. As a result of the warming, thermosteric sea level rose at a rate of 1.6 ± 0.3 mm/yr over the same time period. Maps of yearly heat content anomaly show patterns of warming commensurate with ENSO variability in the tropics, but also show that a large part of the trend in global, oceanic heat content is caused by regional warming at midlatitudes in the Southern Hemisphere. In addition to quantifying interannual variability on a global scale, this work illustrates the importance of maintaining continuously updated monitoring systems that provide global coverage of the world's oceans. Ongoing projects, such as the Jason/TOPEX series of satellite altimeters and the Argo float program, provide a critical foundation for characterizing variability on regional, basin, and global scales and quantifying the oceans' role as part of the climate system.
Convergence and the length spectrum

Abstract The author defines and analyzes the 1 / k length spectra, L 1 / k ( M ) , whose union, over all k ∈ N is the classical length spectrum. These new length spectra are shown to converge in the sense that lim k → ∞ K 1 / k ( M i ) ⊂ L 1 / k ( M ) ∪ { 0 } as M i → M in the Gromov–Hausdorff sense. Energy methods are introduced to estimate the shortest element of L 1 / k , as well as a concept called the minimizing index which may be used to estimate the length of the shortest closed geodesic of a simply connected manifold in any dimension. A number of gap theorems are proven, including one for manifolds, M n , with Ricci ⩾ ( n − 1 ) and volume close to Vol ( S n ) . Many results in this paper hold on compact length spaces in addition to Riemannian manifolds.
Phase Relationships and Low Temperature Heat Capacities of Alloys in the Y5Si4-Y5Ge4 Pseudo Binary System

Abstract Phase compositions and crystal structures of 10 Y5SixGe4−x alloys with x varying from 0 to 4 have been studied by means of X-ray powder diffraction, and their heat capacities at constant pressure have been measured from ∼4 to 350 K using semi-adiabatic calorimetry. The silicide, Y5Si4, belongs to the Gd5Si2Ge2-type crystal structure; the germanide, Y5Ge4, belongs to the Sm5Ge4-type crystal structure. Two solid solutions exist in the Y5SixGe4−x system: alloys with x varying from 4 to 3.5 have the monoclinic Gd5Si2Ge2-type structure, and alloys with x varying from 3.0 to 0 have the orthorhombic Sm5Ge4-type crystal structure. Low temperature heat capacity data indicate the absence of structural transitions below room temperature. The existence and terminations of the solid solution regions of the four structures which occur in the R5SixGe4−x systems, where R is a rare earth element, correlate with the radius ratio of the R metal divided by the weight average radius of the Si and Ge atoms in the given phase.
Iteration at the boundary of the space of rational maps

Let Ratd denote the space of holomorphic self-maps of P1 of degree d≥2, and let μf be the measure of maximal entropy for f∈Ratd. The map of measures f→μf is known to be continuous on Ratd, and it is shown here to extend continuously to the boundary of Ratd in Ratd≃PH0(P1×P1,O(d,1))≃P2d+1, except along a locus I(d) of codimension d+1. The set I(d) is also the indeterminacy locus of the iterate map f→fn for every n≥2. The limiting measures are given explicitly, away from I(d). The degenerations of rational maps are also described in terms of metrics of nonnegative curvature on the Riemann sphere; the limits are polyhedral
The correlation of VLF propagation variations with atmospheric planetary-scale waves

Abstract Variations in the received daytime phase of long distance, cesium-controlled, VLF transmissions are compared to the height variations of the 10 mb isobaric surface during the first 3 months of 1965 and 1969. The VLF phase values are also compared to height variations of constant electron densities in the E -region from Brown and Williams (1971) and to variations of ƒ- min from Deland and Friedman (1972) which have been shown to be well correlated with planetary-scale variations in the stratosphere by Deland and Cavalieri (1973). The VLF phase variations show good correlation with these previous ionospheric measurements and with the 10 mb surfaces. The VLF variations appear to lag the stratospheric variations in the same area by about 4 days during the 1965 period, but lead the latter by about 4 days during the 1969 period. The planetary scale waves in the stratosphere are shown to be travelling eastward on the average in 1965 and westward in 1969. The above correlations are interpreted as due to the propagation of travelling planetary scale waves with westward tilted wave fronts. Upward energy transport due to the vertical structure of those waves is also discussed. These correlations provide further evidence for the coupling between the lower ionosphere at about 70 km altitude (the day-time VLF reflection height) and the stratosphere, and they demonstrate the sensitivity and usefulness of VLF transmissions for studies of planetary wave phenomena.
A three-carbon (n+1+2) ring expansion method for the synthesis of macrocyclic enones. Application to muscone synthesis.

Abstract The three-carbon ring expansion methodology commences with the preparation of a cyclic allene (C9, C11, C13), readily available from the corresponding cycloalkene via dibromocarbene addition and subsequent treatment with methyllithium. Dichloroketene addition to the cyclic allene regioselectively provides the [2+2] cycloadduct, which is reductively dechlorinated with zinc in methanol. The resulting cyclobutanone is then catalytically hydrogenated; cyclobutanone ring opening is affected with trimethylsilyl iodide; immediate dehydroiodination of the resulting β-iodocycloalkanone with diazabicycloundecane (DBU) provides the corresponding macrocyclic enone. The 15-membered enone was converted to d , l -muscone with (CH 3 ) 2 CuLi.
New Strategies in Organic Catalysis: The First Enantioselective Organocatalytic Friedel−Crafts Alkylation

Our laboratory has been engaged in the design of broadly useful new strategies for enantioselective catalysis that utilize organic chemicals as reaction catalysts. In our recent study, we reported that the LUMO-lowering activation of α,β-unsaturated aldehydes using the reversible formation of iminium ions with chiral imidazolidinones 1 (eq 1) is a valuable platform for the development of enantioselective organocatalytic Diels−Alder reactions (eq 2). In this work, we reveal that this catalytic strategy is also amenable to [3 + 2] cycloadditions between nitrones and α,β-unsaturated aldehydes to provide isoxazolidines (eq 3), useful synthons for the construction of biologically important amino acids, β-lactams, amino carbohydrates, and alkaloids. To our knowledge, this is the first example of an organocatalytic 1,3-dipolar cycloaddition.3 Moreover, this study further documents that chiral amines can be employed as asymmetric catalysts for a range of transformations that traditionally utilize metal salts.
Stereocontrolled Synthesis of ent-Grindelic Acid. A Useful Example of Diastereofacial Guidance in an Oxonium Ion-Initiated Pinacolic Ring Expansion

An enantioselective synthesis of (+)-grindelic acid is described, confirming that the dextrorotatory enantiomer is antipodal to the natural diterpenoid. The optically pure bicyclic ketone 5 representing the AB ring system is constructed from the levorotatory Wieland−Miescher ketone and must therefore possess the absolute configuration shown. Coupling of 5 with the 5-lithio derivative of optically active 2,3-dihydrofuran 3 derived from (R)-(−)-linalool was effected for the purpose of realizing acid-catalyzed rearrangement with generation of the appropriate spirocyclic framework. This key step is highly stereocontrolled, leading predominantly to 7. Once the advanced intermediate 15 is available in this fashion, its subsequent exposure to oxidation and dehydration steps led to the target molecule. The synthesis demonstrates unequivocally that natural (−)-grindelic acid is a true labdane diterpenoid.
Advanced designs for non-imaging submillimeter-wave Winston cone concentrators

We describe the design and simulation of several non-imaging concentrators designed to couple submillimeter wavelength radiation from free space into highly overmoded, rectangular, WR-10 waveguide. Previous designs are altered to improve the uniformity of efficiency rather than the efficiency itself. The concentrators are intended for use as adapters between instruments using overmoded WR-10 waveguide as input or output and sources propagating through free space. Previous simulation and measurement have shown that the angular response is primarily determined by the Winston cone and is well predicted by geometric optics theory while the efficiencies are primarily determined by the transition section. Additionally, previous work has shown insensitivity to polarization, orientation and beam size. Several separate concentrator designs are studied, all of which use a Winston cone (also known as a compound parabolic concentrator) with an input diameter ranging from 4 mm to 16 mm, and “throat” diameters of less than 0.5 mm to 4 mm as the initial interface. The use of various length adiabatic circular-to-rectangular transition sections is investigated, along with the effect of an additional, 25 mm waveguide section designed to model the internal waveguide of the power meter. Adapters without a transition section and a rectangular Winston cone throat aperture and double cone configurations are also studied. Adapters are analyzed in simulation for consistent efficiency across the opening aperture.
LHC Predictions from a Tevatron Anomaly in the Top Quark Forward-Backward Asymmetry

We examine the implications of the recent CDF measurement of the top-quark forward-backward asymmetry, focusing on a scenario with a new color octet vector boson at 1-3 TeV. We study several models, as well as a general effective field theory, and determine the parameter space which provides the best simultaneous fit to the CDF asymmetry, the Tevatron top pair production cross section, and the exclusion regions from LHC dijet resonance and contact interaction searches. Flavor constraints on these models are more subtle and less severe than the literature indicates. We find a large region of allowed parameter space at high axigluon mass and a smaller region at low mass; we match the latter to an SU(3)1 × SU(3)2/SU(3) c coset model with a heavy vector-like fermion. Our scenario produces discoverable effects at the LHC with only 1–2 fb−1 of luminosity at $ \sqrt {s} = 7 - 8\;{\text{TeV}} $ . Lastly, we point out that a Tevatron measurement of the b-quark forward-backward asymmetry would be very helpful in characterizing the physics underlying the top-quark asymmetry.
Improving drug dosing in hospitalized patients: automated modeling of pharmacokinetics for individualization of drug dosage regimens.

Abstract Many clinically useful drugs have a narrow range of blood concentrations which are both safe and efficacious. Inter-individual and intra-individual variations in drug disposition are important factors causing blood concentrations of drug to fall outside of the therapeutic range. Modeling of the pharmacokinetics of the individual offers an effective approach to the problem of variation in drug disposition. Previous approaches for the modeling of individual pharmacokinetics have required either extensive computations or access to computer software and hardware in the clinical environment, and special expertise to interpret the results. This paper describes a prototype computer program. PK Monitor, which can, when connected with an appropriate interface, automatically monitor drug dosing and recommend changes that may be required to obtain blood concentrations in the therapeutic range. The software can also detect the occurrence of change in drug disposition which will lead to concentrations outside of the therapeutic range, identify potentially erroneous blood concentration measurements, and assess the need for further blood concentration measurements. This program will be an integral part of the MENTOR therapeutic monitoring system of programs. PK Monitor awaits a complete evaluation with the rest of the MENTOR system, but preliminary simulations suggest reasonable sensitivity and specificity in monitoring for unexpected data and change.
A penetration criterion for double-walled structures subject to meteoroid impact.

1 Hirschberg, M. H. and Mendleson, A., "Analysis of Stresses and Deflections in a Disk Subjected to Gyroscopic Forces," TN-4218, 1958, NACA. 2 Meirovitch, L., "Bending Vibrations of a Disk Subjected to Gyroscopic Forces," Journal of the Astronautical Sciences, Vol. 8, 1961, pp. 88-93. 3 Johnson, M. W., "On the Dynamics of Shallow Elastic Members," Proceedings of the Symposium on the Theory of Thin Elastic Shells (Delft), North-Holland, Amsterdam, 1960, pp. 281-300. 4 Schlack, A. L. and Kessel, P. G., "Gyroscopically Induced Vibrations of Plates and Membranes," AIAA Journal, Vol. 6, No. 12, Dec. 1968, pp. 2360-2363. 5 Timoshenko, S. and Woinowsky-Kreiger, S., Theory of Plates and Shells, McGraw-Hill, New York, 1959. Wah, T., "Vibration of Circular Plates," Journal of the Acoustical Society of America, Vol. 34, No. 3, 1962, pp. 275-281. 7 Weiner, R. S., "Forced Axisymmetric Motions of Circular Elastic Plates," Journal of Applied Mechanics, Vol. 4, 1965, pp. 893-898. 8 Stoker, J. J., Nonlinear Vibrations, Interscience, New York, 1950, Chap. VI. 9 McLachlan, N. W., Theory and Applications of Mathieu Functions, Dover, New York, 1964.
Convenient routes to symmetrical benzils and chiral 1,2-diaryl-1,2-diaminoethanes, useful controllers and probes for enantioselective synthesis

Abstract Pathways for the diastereoselective preparation of chiral 1,2-diaryl-1,2-diaminoethanes from ArCOOH, ArCHO or ArBr are described.
Electroreduction of 2-oxazolines

Abstract The cathodic behavior of 2-pheny1-4,4-dimethyl-2-oxazoline (4), 2,4,4-trimethyl-2-oxazoline (7) and 2-(1,1-dimethylethyl)-4,4-dimethyl-2-oxazoline (8) at Hg electrodes was investigated. A reduction peak for 4 at -2.49V(SCE), was observed by cyclic voltammetry (CV). Preparative reduction of 4 at a mercury pool yielded exclusively N-benzyl-2-amino-2-methylpropanol (6) in a high yield (91%). The electrolysis procedure was simple utilizing constant current and an undivided cell, and the pH remained neutral throughout the reaction. The 2-oxazolines 7 and 8 did not exhibit CV reduction peaks and were recovered after attempts of preparative electrolysis. CV and nmr measurements indicate that the reduction of 4 involves initial formation of the corresponding oxazolidine 5 followed by ring cleavage to the easily reducible tautomeric imine 5a which reacts to give 6.
Nutrition and Numbers in the Third World

The sixth annual W. O. Atwater Memorial Lecture, sponsored by the Agriculture Research Service, U. S. Department of Agriculture, was given 28 February 1974, at the 140th Annual Meeting of the American Association for the Advancement of Science. These lectures commemorate the life and work of W. O. Atwater, who established the science of modern human nutrition in the United States. Through the lectureship, ARS gives special recognition to individuals who have made outstanding contributions to fields of science broadly related to human nutrition, or advanced public understanding of the role of science in meeting world food needs. This lecture was originally published in Nutrition Reviews, Vol. 32, No. 2, p. 9 7-104, 1974.
On the non-relativistic limit of the quantum sine-Gordon model with integrable boundary condition

We show that the generalized Calogero-Moser model with a boundary potential of the Poschl-Teller type describes the non-relativistic limit of the quantum sine-Gordon model on a half-line with a Dirichlet boundary condition.
Sensitivity of TOMS aerosol index to boundary layer height: Implications for detection of mineral aerosol sources

[1] The TOMS aerosol index (AI) is proposed as a powerful tool in determining the sources of mineral aerosols. The sensitivity of the AI to the height of the aerosol layer has been noted previously, but the implications of this sensitivity for deducing sources has not been explicitly considered. Here, we present a methodology and sensitivity test to show the importance of spatial and temporal variations of the planetary boundary layer height to deducing sources using the AI. These results suggest that while dry topographic low sources may be large sources of desert dust, conclusions eliminating other sources may be premature, especially when these sources occur on the edges of deserts, where boundary layer heights are lower, and human influences potentially more important. The compounding problem of differentiating downwind transport and local sources suggests it may not currently be possible to use the AI to conclusively determine mineral aerosol source regions.
Some Aspects of Colloidal Nanoparticle Stability, Catalytic Activity, and Recycling Potential

In this review article, we examine many important aspects of the nanocatalysis field such as size and shape dependent nanocatalysis, the stability of nanoparticles during its catalytic function, and their recycling potential. We provide an overview of some of the work in the literature pertinent to these topics and also discuss some of our own work in these important areas. Some examples of how the catalytic activity is affected by the size of the nanoparticles are discussed as well as how the catalytic process affects the nanoparticle size after its catalytic function. The synthesis of platinum nanoparticles of different shapes is surveyed and the dependence of nanoparticle shape on the catalytic activity is discussed. In addition, changes in the nanoparticle shape and resulting changes in the catalytic activity are also discussed. The recycling potential of the metal nanocatalysts is also highlighted. In addition, a simple examination of the mechanism of nanocatalysis is discussed.
An Intervehicular Spacing Display for Improved Car-Following Performance

A driver's inability to detect small headway changes and small relative velocities is a primary reason for his poor car-following performance. This can be greatly improved if he is given information?headway and relative velocity?concerning the state of a lead car. This may be provided visually, tactually, or audibly. In the study reported, a control stick with a built-in kinesthetictactile display was tested in a car-following situation. Performances with this display were compared to those obtained when no aiding was used in a similar situation. Sizable reductions in velocity variance and headway variance were obtained for the aided case relative to the unaided case. These were obtained for headways of 23 feet at 30 mi/h and 33 feet at 40 mi/h. Thus, this display can be effectively used at short headways.
A digital system for on-line studies of dynamical systems

The study of dynamical systems with the aid of analog and digital computers has developed rapidly in the past two decades. Increased interest in systems described by differential equations which are nonlinear or have time-varying coefficients, has resulted in more reliance on techniques requiring on-line computation. Usually less is known a priori of how the solutions will develop or what parameter values or initial conditions should be used. The recent trend to using hybrid computers (combinations of digital and analog equipment) has been motivated by the desire to study complex dynamical systems with computer configurations which are designed with particular classes of problems in mind. Extensive use of display, plotting, and printing equipment as well as elaborate consoles attest the on-line capability of such computers.
Status of the Fermilab Antiproton source

Abstract The Fermilab antiproton source has been operated for two commissioning and running periods and has allowed the operation of the Tevatron Collider. The normal operating mode of the source is described, and the recent performance is compared with the design specifications. The reasons for “missing factors” are discussed.
An empirical analysis of the propensity of academics to engage in informal university technology transfer.

Formal university technology transfer mechanisms, through licensing agreements, research joint ventures, and university-based startups, have attracted considerable attention in the academic literature. Surprisingly, there has been little systematic empirical analysis of the propensity of academics to engage in informal technology transfer. This paper presents empirical evidence on the determinants of three types of informal technology transfer by faculty members: transfer of commercial technology, joint publications with industry scientists, and industrial consulting. We find that male, tenured and research-grant active faculty members are more likely to engage in all three forms of informal technology transfer.
A Bayesian approach to subvoxel tissue classification in NMR microscopic images of trabecular bone

NMR microscopy is currently being used as an investigational tool for the evaluation of micromorphometric parameters of trabecular bone as a possible means to assess its strength. Since, typically, the image voxel size is not significantly smaller than individual trabecular elements, partial volume blurring can be a major complication for accurate tissue classification. In this paper, a Bayesian segmentation technique is reported that achieves improved subvoxel tissue classification. Each voxel is subdivided either into eight subvoxels twice the original resolution, or up to four subvoxels along the transaxial direction and the subvoxels optimally classified as volume blurring, the likelihood for the number of marrow subvoxels in each voxel can be computed on the basis of its measured signal. To resolve the ambiguity of the location of the marrow subvoxels, a Gibbs distribution is introduced to model the interaction between the subvoxels. Neighboring subvoxel pairs with the same tissue label are encouraged, and pairs with distinct labels are penalized. The segmentation is achieved by maximizing the a posteriori probability of the label image using the block ICM (iterative conditional mode) algorithm. The potential of the proposed technique is demonstrated in real and synthetic NMR microscopic images.
A sliding interface method for unsteady unstructured flow simulations

The objective of this work is to develop a sliding interface method for simulations involving relative grid motion that is fast and efficient and involves no grid deformation, remeshing, or hole cutting. The method is implemented into a parallel, node-centred finite volume, unstructured viscous flow solver. The rotational motion is accomplished by rigidly rotating the subdomain representing the moving component. At the subdomain interface boundary, the faces along the interface are extruded into the adjacent subdomain to create new volume elements forming a one-cell overlap. These new volume elements are used to compute a flux across the subdomain interface. An interface flux is computed independently for each subdomain. The values of the solution variables and other quantities for the nodes created by the extrusion process are determined by linear interpolation. The extrusion is done so that the interpolation will maintain information as localized as possible. The grid on the interface surface is arbitrary. The boundary between the two subdomains is completely independent from one another; meaning that they do not have to connect in a one-to-one manner and no symmetry or pattern restrictions are placed on the grid. A variety of numerical simulations were performed on model problems and large-scale applications to examine conservation of the interface flux. Overall solution errors were found to be comparable to that for fully connected and fully conservative simulations. Excellent agreement is obtained with theoretical results and results from other solution methodologies. Copyright © 2006 John Wiley & Sons, Ltd.
A hybrid searching scheme in unstructured P2P networks

The existing searching schemes in peer-to-peer (P2P) networks are either forwarding-based or non-forwarding based. In forwarding-based schemes, queries are forwarded from the querying source to the query destination nodes. These schemes offer low state maintenance. However, querying sources do not entirely have control over query processing. In non-forwarding based methods, queries are not forwarded and the querying source directly probes its neighbors for the desired files. Non-forwarding searching provides querying sources flexible control over the searching process at the cost of high state maintenance. In this paper, we seek to combine the powers of both forwarding and non-forwarding searching schemes. We propose an approach where the querying source directly probes its own extended neighbors and forwards the query to a subset of its extended neighbors and guides these neighbors to probe their own extended neighbors on its behalf. Our approach can adapt query processing to the popularity of the sought files without having to maintain a large set of neighbors because its neighbors' neighbors are also in the searching scope due to the 1-hop forwarding inherent in our approach. It achieves a higher query efficiency than the forwarding scheme and a better success rate than the non-forwarding approach. To the best of our knowledge, the work in this paper is the first one to combine forwarding and non-forwarding P2P searching schemes. Experimental results demonstrate the effectiveness of our approach.
Subgroup-Based Adaptive (SUBA) Designs for Multi-arm Biomarker Trials

Targeted therapies based on biomarker profiling are becoming a mainstream direction of cancer research and treatment. Depending on the expression of specific prognostic biomarkers, targeted therapies assign different cancer drugs to subgroups of patients even if they are diagnosed with the same type of cancer by traditional means, such as tumor location. For example, Herceptin is only indicated for the subgroup of patients with HER2+ breast cancer, but not other types of breast cancer. However, subgroups like HER2+ breast cancer with effective targeted therapies are rare, and most cancer drugs are still being applied to large patient populations that include many patients who might not respond or benefit. Also, the response to targeted agents in humans is usually unpredictable. To address these issues, we propose subgroup-based adaptive (SUBA), designs that simultaneously search for prognostic subgroups and allocate patients adaptively to the best subgroup-specific treatments throughout the course of the trial. The main features of SUBA include the continuous reclassification of patient subgroups based on a random partition model and the adaptive allocation of patients to the best treatment arm based on posterior predictive probabilities. We compare the SUBA design with three alternative designs including equal randomization, outcome-adaptive randomization, and a design based on a probit regression. In simulation studies, we find that SUBA compares favorably against the alternatives.
CPT-symmetry studies with antihydrogen

Various approaches to physics beyond the Standard Model can lead to small violations of CPT invariance. Since CPT symmetry can be measured with ultra-high precision, CPT tests offer an interesting phenomenological avenue to search for underlying physics. We discuss this reasoning in more detail, comment on the connection between CPT and Lorentz invariance, and review how CPT breaking would affect the (anti)hydrogen spectrum.
The hierarchy of local minimums in polynomial optimization

This paper studies the hierarchy of local minimums of a polynomial in the vector space $$\mathbb {R}^n$$Rn. For this purpose, we first compute $$H$$H-minimums, for which the first and second order necessary optimality conditions are satisfied. To compute each $$H$$H-minimum, we construct a sequence of semidefinite relaxations, based on optimality conditions. We prove that each constructed sequence has finite convergence, under some generic conditions. A procedure for computing all local minimums is given. When there are equality constraints, we have similar results for computing the hierarchy of critical values and the hierarchy of local minimums.
Locally unknotted spines of Heegaard splittings

We show that under reasonable conditions, the spines of the handlebodies of a strongly irreducible Heegaard splitting will intersect a closed ball in a graph which is isotopic into the boundary of the ball. This is in some sense a generalization of the results by Scharlemann on how a strongly irreducible Heegaard splitting surface can intersect a ball. AMS Classification 57M27; 57Q10
CCD Photometry of the Globular Cluster NGC 4833 and Extinction Near the Galactic Plane

We present CCD photometry for the Galactic globular cluster NGC 4833. Our BVI color-magnitude diagrams extend from above the tip of the red giant branch to several magnitudes below the main-sequence turnoff. The principal sequences of the cluster show the effects of differential reddening. We have created a local extinction map, consistent with IRAS and COBE DIRBE dust maps of the region. We use our map to correct the colors and magnitudes of each star to the value at the cluster center. The cluster horizontal branch (HB) is predominately blueward of the instability strip with 13 confirmed RR Lyrae variables and five additional RR Lyrae candidates. Using the 11 confirmed RR Lyraes measured on our images and the differential reddening corrected photometry, we calculate V(HB) = 15.56 ± 0.063. We have used the simultaneous reddening and metallicity method of Sarajedini to find the mean reddening of the cluster E(B-V) = 0.32 ± 0.03, and the mean metallicity [Fe/H] = -1.83 ± 0.14. As for the age of NGC 4833, we find provisional evidence that NGC 4833 is 2 ± 1 Gyr older than the average of M92 and M5. A more definitive conclusion must await higher resolution imaging of the cluster core where the effects of differential reddening are minimized.
Fluid-Leakoff Delineation in High-Permeability Fracturing

Starting from the original concept proposed by Carter, Howard and Fast, this paper reviews the description of fracturing fluid leakoff in view of modeling flow in porous media. It is shown how various linear leakoff models have been developed and why a new, radial leakoff concept is necessary for high-permeability fracturing, where the injection time is commensurable to the response time of the reservoir. Using Laplace space methods, the new radial leakoff law is calculated and compared to linear leakoff. For comparison purposes a calibration test executed in high-permeability formation is interpreted using several approaches, namely: linear leakoff1bulk leakoff coefficient; filtercake resistance1linear flow in the formation and finally, filtercake resistance1radial flow in the formation.
Apparent Transition Behavior of Widely-Used Turbulence Models

The Spalart-Allmaras and the Menter SST k-omega turbulence models are shown to have the undesirable characteristic that, for fully turbulent computations, a transition region can occur whose extent varies with grid density. Extremely fine two-dimensional grids over the front portion of an airfoil are used to demonstrate the effect. As the grid density is increased, the laminar region near the nose becomes larger. In the Spalart-Allmaras model this behavior is due to convergence to a laminar-behavior fixed point that occurs in practice when freestream turbulence is below some threshold. It is the result of a feature purposefully added to the original model in conjunction with a special trip function. This degenerate fixed point can also cause non-uniqueness regarding where transition initiates on a given grid. Consistent fully turbulent results can easily be achieved by either using a higher freestream turbulence level or by making a simple change to one of the model constants. Two-equation k-omega models, including the SST model, exhibit strong sensitivity to numerical resolution near the area where turbulence initiates. Thus, inconsistent apparent transition behavior with grid refinement in this case does not appear to stem from the presence of a degenerate fixed point. Rather, it is a fundamental property of the k-omega model itself, and is not easily remedied.
Sequences of LCT-polytopes

To r ideals on a germ of smooth variety X one attaches a rational polytope in the r-dimensional Euclidean space (the LCT-polytope) that generalizes the notion of log canonical threshold in the case of one ideal. We study these polytopes, and prove a strong form of the Ascending Chain Condition in this setting: we show that if a sequence P_m of such LCT-polytopes converges to a compact subset Q in the Hausdorff metric, then Q is equal to the intersection of all but finitely many of the P_m. Furthermore, Q is an LCT-polytope.
X-Raying the Ultraluminous Infrared Starburst Galaxy and Broad Absorption Line QSO Markarian 231 with Chandra

With 40 ks of Clzandra ACIS-S3 exposure, new information on both the starburst and QSO components of the X-ray emission of Markarian 231, an ultraluminous infrared galaxy and broad absorption line QSO, has been obtained. The bulk of the X-ray luminosity is emitted from an unresolved nuclear point source, and the spectrum is remarkably hard, with the majority of the flux emitted above 2 keV. Most notably, significant nuclear variability (a decrease of -45% in approximately 6 hr) at energies above 2 keV indicates that Chuizdra has probed within light-hours of the central black hole. Although we concur with Maloney & Reynolds that the direct continuum is not observed, this variability coupled with the 188 eV upper limit on the equivalent width of the Fe K o emission line argues against the reflection-dominated model put forth by these authors based on their ASCA data. Instead, we favor a model in which a small, Compton-thick absorber blocks the direct X-rays, and only indirect, scattered X-rays from multiple lines of sight can reach the observer. Extended soft, thermal emission encompasses the optical extent of the galaxy and exhibits resolved structure. An off-nuclear X-ray source with a 0.35-8.0 keV luminosity of Lx = 7 x 10 sup39 ergs s sup -1 , consistent with the ultraluminous X-ray sources in other nearby starbursts, is detected. We also present an unpublished Faint Object Spectrograph spectrum from the Hirhhle Spuce Telescope archive showing the broad C IV absorption.
Black Holes and Solitons in String Theory

We review various aspects of classical solutions in string theories. Emphasis is placed on their supersymmetry properties, their special roles in string dualities and microscopic interpretations. Topics include black hole solutions in string theories on tori and N=2 supergravity theories; p-branes; microscopic interpretation of black hole entropy. We also review aspects of dualities and BPS states.
Reactions between dimanganese, dirhenium, and manganese–rhenium decacarbonyl and oxidants

Abstract The dimetal decacarbonyls M 2 (CO) 10 , where M 2 = Mn 2 , MnRe, and Re 2 , do not react with anionic strong oxidants such as Fe(CN) 6 3− or IrCl 6 2− in CH 3 CN solvent nor with neutral or cationic weak oxidants. Strong cationic oxidants such as NO + , Fe(phen) 3 3+ , and Cu 2+ rapidly oxidize M 2 (CO) 10 to 2M(CO) 5 (NCCH 3 ) + in acetonitrile solvent. The kinetics for the reaction suggest it proceeds according to a bimolecular outer sphere mechanism.
Laser focusing of atoms: a particle-optics approach

The use of a TEM01*-mode laser beam has been proposed as a means of focusing an atomic beam to nanometer- scale spot diameters. We have analyzed the classical trajectories of atoms through a TEM01*-mode laser beam, using methods developed for particle optics. The differential equation that describes the properties of the: first- order paraxial lens hi exactly the same form as the bell-shaped magnetic Newtonian lens that was first analyzed by Glaser for the focusing of electrons in an electron-microscope objective. We calculate the first-order properties of the lens, obtaining cardinal elements that are valid over the entire operating range of the lens including the thick and the immersion regimes. Contributions to the spot size are discussed, including four aberrations plus diffraction and atomic-beam-collimation effects. Explicit expressions for spherical chromatic, spontaneous-emission, and dipole-fluctuation aberrations are obtained. Examples are discussed for a sodium atomic beam, showing that subnanometer-diameter spots may be achieved with reasonable laser and atomic- beam parameters. Optimization of the lens is also discussed.
Public Policy, Private Preferences, and the Japanese Trade Pattern

As nontariff forms of trade protection proliferate it has become more difficult to analyze the impact of trade policy on trade flows. In a number of well-known papers researchers have attempted to infer the impact of trade policy indirectly by ascribing to trade policy the differences between actual and predicted trade flows. Much of the work has been applied to analysis of Japanese trade policy, and the conclusions of these studies have differed widely. Some previous research has also ascribed a role to the keiretsu, or networks of affiliated firms, in explaining Japan's apparently distinctive trade performance. This paper presents a model that integrates data on factor endowments, observable protection in traditional and nontraditional forms, and the keiretsu. It extends existing research in two principal ways. First, alternative cross-national models of comparative advantage are nested to permit the identification of critical modeling assumptions underlying the divergent conclusions of the previous stu...
Pulsar Parallaxes at 5 GHz with the Very Long Baseline Array

We present the first pulsar parallaxes measured with phase-referenced pulsar VLBI observations at 5 GHz. Because of the steep spectra of pulsars, previous astrometric measurements have been at lower frequencies. However, the strongest pulsars can be observed at 5 GHz, offering the benefit of lower combined ionospheric and tropospheric phase errors, which usually limit VLBI astrometric accuracy. The pulsars B0329+54, B0355+54, and B1929+10 were observed for seven epochs spread evenly over 2 years. For B0329+54, large systematic errors led to only an upper limit on the parallax (π < 1.5 mas). A new proper motion and parallax were measured for B0355+54 (π = 0.91 ± 0.16 mas), implying a distance of 1.04 kpc and a transverse velocity of 61 km s-1. The parallax and proper motion for B1929+10 were significantly improved (π = 2.77 ± 0.07 mas), yielding a distance of 361 pc and a transverse velocity of 177 km s-1. We demonstrate that the astrometric errors are correlated with the angular separation between the phase-reference calibrator and the target source, with significantly lower errors at 5 GHz as compared to 1.6 GHz. Finally, based on our new distance determinations for B1929+10 and B0355+54, we derive or constrain the luminosities of each pulsar at high energies. We show that, for thermal emission models, the emitting area for X-rays from PSR B1929+10 is roughly consistent with the canonical size for a heated polar cap and that the conversion of spin-down power to γ-ray luminosity in B0355+54 must be low. The new proper motion for B1929+10 also implies that its progenitor is unlikely to have been the binary companion of the runaway O star ζ Ophiuchi.
Alfven-wave particle interaction in finite-dimensional self-consistent field model

A low-dimensional Hamiltonian model is derived for the acceleration of ions in finite-amplitude Alfven waves in a finite-pressure plasma sheet. The reduced low-dimensional wave–particle Hamiltonian is useful for describing the reaction of the accelerated ions on the wave amplitudes and phases through the self-consistent fields within the envelope approximation. As an example, we show that for a single Alfven wave in the central plasma sheet of the Earth’s geotail, modeled by the linear pinch geometry called the Harris sheet, the time variation of the wave amplitude during the acceleration of fast protons.
AN ASSORTMENT OF NEGATIVELY CURVED ENDS

Motivated by recent groundbreaking work of Ontaneda, we describe a sizable class of closed manifolds such that the product of each manifold in the class with ℝ admits a complete metric of bounded negative sectional curvature which is an exponentially warped near one end and has finite volume near the other end.
Some factors in the regulation of central serotonergic synapses.

Abstract For a number of years release, reuptake, vesicular storage, and degradation via monoamine oxidase were the exclusive foci in chemical studies of the regulation of central serotonergic synapses. This brief review describes some other factors, including the brain levels of tryptophan and uptake processes in the nerve ending relevant to the substrate, the activity and amount of tryptophan hydroxylase in cell bodies and nerve endings, and a potential regulatable parasynaptic inactivation process, N-methylation. In chronic and acute drug studies some of these factors appear to function to compensate for acute perturbations in central serotonergic synaptic processes.
Comparison of the Nimbus-4 BUV ozone data with the Ames two-dimensional model

A comparison is made of the first two years of Nimbus-4 backscattered ultraviolet (BUV) ozone measurements with the predictions of the Ames two-dimensional model. The ozone observations used in this study consist of the mixing ratio on the 1-, 2-, 5-, and 10-mb pressure surfaces. These data are zone and time averaged to obtain seasonal means for 1970 and 1971 and are found to show strong and repeatable meridional and seasonal dependencies. The model used for comparison with the observations extends from 80°N to 80°S latitude and from altitudes of 0 to 60 km with 5° horizontal grid spacing and 2.5-km vertical grid spacing. The chemical reaction and photolysis rate constants used in the model are those recommended in the report of the NASA Panel for Data Evaluation (1979) Chemical reaction and photolysis rates are diurnally averaged, and the photodissociation rates are corrected for the effects of scattering.
A superquadratic infeasible-interior-point method for linear complementarity problems

We consider a modification of a path-following infeasible-interior-point algorithm described by Wright. In the new algorithm, we attempt to improve each major iterate by reusing the coefficient matrix factors from the latest step. We show that the modified algorithm has similar theoretical global convergence properties to those of the earlier algorithm while its asymptotic convergence rate can be made superquadratic by an appropriate parameter choice.
A short proof of the Arendt-Chernoff-Kato theorem

We give a short new proof of the Arendt-Chernoff-Kato theorem, which characterizes generators of positive C0 semigroups in order unit spaces. The proof avoids half-norms and subdifferentials and is based on a sufficient condition for an operator to have positive inverse, which is new even for matrices.
A unified framework for pro-poor growth analysis

Starting with a general impact indicator as an evaluation criterion, The author offers an integrative framework for a unified discussion of various concepts and measures of pro-poor growth emerging from the current literature. He shows that whether economic growth is considered pro-poor depends fundamentally on the choice of evaluative weights. In addition, the author's framework leads to a new indicator of the rate of pro-poor growth that can be interpreted as the equally distributed equivalent growth rate. This is a distribution-adjusted rate of growth that depends on the chosen level of inequality aversion. Illustrations based on data for Indonesia in the 1990s show a strong link between growth and poverty reduction in that country. A decomposition of the observed poverty outcomes reveals the extent to which changes in inequality have blunted the poverty impacts of both growth and contraction. Finally, the results also demonstrate that absolute and relative indicators of pro-poor growth can lead to conflicting conclusions from the same set of facts.
Optimal Design of Acoustical Foam Treatments

A finite element model for elastic porous materials is presented that allows for interfaces with adjacent acoustical media that are arbitrarily oriented with respect to the global coordinate system. The foam finite element is based on a complete elastic porous material theory that can account for all the three wave types known to be significant in foams. Example problems are used to illustrate the application of foam finite elements to the optimal design of a foam wedge terminating a waveguide. The wedge angle is used as a design parameter (while the wedge volume is held constant) and the performance measure is the frequency-averaged absorption coefficient.
CHIRALLY EXTENDED QUANTUM CHROMODYNAMICS

We propose an extended Quantum Chromodynamics (XQCD) Lagrangian in which the fermions are coupled to elementary scalar fields through a Yukawa coupling which preserves chiral invariance. Our principle motivation is to find a new lattice formulation for QCD which avoids the source of critical slowing down usually encountered as the bare quark mass is tuned to the chiral limit. The phase diagram and the weak coupling limit for XQCD are studied. They suggest a conjecture that the continuum limit of XQCD is the same as the continuum limit of conventional lattice formulation of QCD. As examples of such universality, we present the large N solutions of two prototype models for XQCD, in which the mass of the spurious pion and sigma resonance go to infinity with the cut-off. Even if the universality conjecture turns out to be false, we believe that XQCD will still be useful as a low energy effective action for QCD phenomenology on the lattice. Numerical simulations are recommended to further investigate the possible benefits of XQCD in extracting QCD predictions.