cssi/SciSciGPT-SciSciNet huggingface dataset:
An iterative combination scheme for multimodal visual feature detection

Abstract We address the problem of multimodal visual feature detection where several individual heterogeneous measures (i.e., feature detectors) are merged into a single saliency value. We survey a number of techniques for the normalization and integration steps used in existing combination methods. A new approach, the iterative combination scheme, is proposed to iteratively learn a classifier that infers a non-linear model to combine different feature detectors. We evaluate and compare the combination strategies presented using an objective methodology, the repeatability criterion, and a dataset with real images of 21 cluttered scenes of 3D objects. Initially, our evaluation tested the performance of individual feature detectors. Considering the overall performance for all 7 scenes in the testing dataset, the Difference of Gaussian detector achieved the best repeatability rate, 54.41%. In our evaluation, we tested the performance of combining all possible sets of feature detectors. Among all possible sets, the triplet composed of Laplacian of Gaussian, Hessian Matrix, and Gradient Magnitude achieved the best performance of 58.93% repeatability. We used this combination of detectors to initialize the iterative combination scheme which was able to improve the performance to 66.62%.
A Cu2-O2 Complex. Crystal Structure and Characterization of a Reversible Dioxygen Binding System

[(LCu) 2 (O 2 )][PF 6 ] 2 •5Et 2 O cristallise dans le systeme triclinique, groupe d'espace P1 et sa structure est affinee jusqu'a R=20,0581
Dependence of Soot Production on Fuel Blend Characteristics and Combustion Conditions

Experimental results are presented which concern soot formation characteristics of fuel blends and the impact of operating conditions on soot formation. The fuel blend evaluation considered a two-component mixture composed of a Group 1 and a Group 2 hydrocarbon. Operating characteristics which were evaluated included reactor mass loading (mass flow into the reactor) and inlet temperature. Results have been analyzed to develop useful correlations which are in general agreement with existing mechanistic concepts of the soot formation process. Paper No. 79-GT-155.
Error estimate of a fourth-order Runge-Kutta method with only one initial derivative evaluation

In the numerical solution of differential equations it is desirable to have estimates of the local discretization (or truncation) errors of solutions at each step. The estimate may be used not only to provide some idea of the errors, but also to indicate when to adjust the step size. If the magnitude of the estimate is greater than the preassigned upper bound, the step size is reduced to achieve smaller local errors. If the magnitude of the estimate is less than the preassigned lower bound, the step size is increased to save the computing time.
Recursive computational depth

In the 1980's, Bennett introduced computational depth as a formal measure of the amount of computational history that is evident in an object's structure. In particular, Bennett identified the classes of weakly deep and strongly deep sequences, and showed that the halting problem is strongly deep. Juedes, Lathrop, and Lutz subsequently extended this result by defining the class of weakly useful sequences, and proving that every weakly useful sequence is strongly deep.
FRC Simulations using the NIMROD Code

The Plasma Science and Innovation Center (PSI-Center) is benchmarking and refining the NIMROD code for simulations of field-reversed configurations (FRCs). The NIMROD code can resolve highly anisotropic heat conduction and viscosity (Sovinec et al., JCP 195:355, 2004). This combined with its ability to include two-fluid effects, allows us to capture more detailed physics than previous calculations. Recent modifications to the radial boundary conditions capture most of the effects of multiple discrete coils found in many FRC experiments. When the tangential electric field on the end boundaries (open field lines) is set to zero and the Hall term is included in the calculation, the open field-line plasma spins up due to end-shorting effects, which in turn couples to the main FRC plasma through shear viscosity. The spin-up rate is found to be sensitive to the open field-line plasma profile. We are also investigating recent observations (Guo et al., Phys. Rev. Lett. 95:175001, 2005] that imply that a small toroidal field could help stabilize the n = 2 rotational instability. We find that a combination of a relatively weak toroidal magnetic field and the inclusion of the Hall term in the calculation can lead to a change in the character of the mode and a dramatic reduction to its growth rate.
Interpolation of non-abelian lattice gauge fields

Abstract We propose a method for interpolating non-abelian lattice gauge fields to the continuum, or to a finer lattice, which satisfies the properties of (i) transverse continuity, (ii) (lattice) rotation and translation covariance, (iii) gauge covariance, and (iv) locality. These are the properties required for use in our earlier proposal for non-perturbative formulation and simulation of chiral gauge theories.
Pd(II)-catalyzed olefination of electron-deficient arenes using 2,6-dialkylpyridine ligands.

Pd(II)-catalyzed meta-olefination of highly electron-deficient arenes is achieved through the use of a rationally designed mutually repulsive ligand. The combination of directed and nondirected C−H functionalization of arenes provides a versatile route for the synthesis of highly sought after 1,2,4-trisubstituted arenes.
Radical cyclization approach to spirocyclohexadienones

Cyclization of an aryl radical at the ipso position of a p-O-aryl-substituted acetamide or benzamide generates oxindoles or quinolones bearing spirocyclohexadienone rings. This versatile reaction is applied to formal syntheses of the vasopressin inhibitor SR121463A and aza-galanthamine.
Creating successful entrepreneurial ventures in IT

Four factors that are vital for the critical success of entrepreneurs when seeking opportunities in the computing and information technology (IT) sectors are defined. They are: 1) the growth rate of the target market, 2) the timing of entry into the market, 3) the near-term revenue potential, and 4) the impact of cyclical nature of the industry. These factors are utilized to evaluate the future market in the emerging fields of ubiquitous computing, e-commerce, and information security. Practical guidelines for entrepreneurs to assess opportunities are offered, and it is concluded that there are bright prospects for entrepreneurs in these fields. (SRY)
Inner‐city networking: Models and opportunities

(1995). Inner‐city networking: Models and opportunities. Journal of Urban Technology: Vol. 3, No. 1, pp. 19-28.
A Modular Approach to Sustainability Assessment and Decision Support in Chemical Process Design

In chemical and allied industries, process design sustainability has gained public concern in academia, industry, government agencies, and social groups. Over the past decade, a variety of sustainability indicators have been introduced, but with various challenges in application. It becomes clear that the industries need urgently practical tools for conducting systematic sustainability assessment on existing processes and/or new designs and, further, for helping derive the most desirable design decisions. This paper presents a systematic, general approach for sustainability assessment and design selection through integrating hard (quantitative) economic and environmental indicators along with soft (qualitative) indicators for social criteria into design activities. The approach contains four modules: a process simulator module, an equipment and inventory acquisition module, a sustainability assessment module, and a decision support module. The modules fully utilize and extend the capabilities of the process simulator Aspen Plus, Aspen Simulation Workbook, and a spreadsheet, where case model development, data acquisition and analysis, team contribution assessment, and decision support are effectively integrated. The efficacy of the introduced approach is illustrated by the example of biodiesel process design, where insightful sustainability analysis and persuasive decision support show its superiority over commonly practiced technoeconomy evaluation approaches.
On Equilibrium Pricing under Parameter Uncertainty

Prior theoretical work on estimation risk generally has been restricted to single-period, returns-based models in which the investor must estimate the vector of expected returns but the covariance matrix is known. This paper extends the literature on parameter uncertainty in several ways. First, we analyze asymmetric parameter uncertainty in a model based on payoffs. Second, we explore the effects of both symmetric and asymmetric estimation risk on equilibrium asset prices when the covariance matrix for payoffs must also be estimated. Finally, we investigate the effects on equilibrium of asymmetric parameter uncertainty in a simple multiperiod model.
Subsets and modular features of standard APT

The APT (Automatically Programmed Tool) N/C language was developed in 1956 at M.I.T.'s Servomechanisms Laboratory by D. T. Ross. Since that time, the language has been widely used at N/C installations in the United States for all categories of N/C programming. Since 1961, further APT System development has been directed by the Illinois Institute of Technology Research Institute under Dr. S. Hori. Use of the APT Language became so universally accepted that in 1963, the American Standards Association (now the United States of America Standards Institute) initiated an activity to generate a United States standard for the APT Language.
Studies of yeast cell oxygenation and energetics by laser fluorometry of reduced nicotinamide adenine dinucleotide

It is of fundamental importance for biological scientists to assess cellular energetics. Under aerobic conditions, the tricarboxylic acid cycle (TCA cycle) is coupled with the mitochondrial electron cascade pathway to provide the cell with energy. The nicotinamide adenine dinucleotide-conjugated pair (NAD and NADH) is the coenzyme in numerous important biomedical reactions which include several important dehydrogenase reactions in the TCA cycle. Based on Le Chatelier's principle, NADH will accumulate when this energy production mechanism is impaired. The relative amounts of NAD and NADH in a cell are defined as the redox state of the cell (Williamson et.al. 1967) which provides a valuable index of cellular energetics. The sum of the amounts of NAD and NADH in a cell may be assumed to be constant during a finite time; therefore, a reliable means of measuring the NADH concentration would provide us with a useful indicator of tissue viability. Traditionally, the quantities of NADH and NAD may be measured by chemical assay methods. We can avoid these tediois analyses by exploiting the significant difference between the ultraviolet absorption spectra of this redox pair. However, because of the opacity of biological samples and the interference of other biochemicals that also absorb ultraviolet radiation, measurement of NADH and NAD+ concentrations in vivo by absorption spectroscopy is not feasible.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Vertebral compression fractures after spine irradiation using conventional fractionation in patients with metastatic colorectal cancer.

PURPOSE: To evaluate the risk of vertebral compression fracture (VCF) after conventional radiotherapy (RT) for colorectal cancer (CRC) with spine metastasis and to identify risk factors for VCF in metastatic and non-metastatic irradiated spines. MATERIALS AND METHODS: We retrospectively reviewed 68 spinal segments in 16 patients who received conventional RT between 2009 and 2012. Fracture was defined as a newly developed VCF or progression of an existing fracture. The target volume included all metastatic spinal segments and one additional non-metastatic vertebra adjacent to the tumor-involved spines. RESULTS: The median follow-up was 7.8 months. Among all 68 spinal segments, there were six fracture events (8.8%) including three new VCFs and three fracture progressions. Observed VCF rates in vertebral segments with prior irradiation or pre-existing compression fracture were 30.0% and 75.0% respectively, compared with 5.2% and 4.7% for segments without prior irradiation or pre-existing compression fracture, respectively (both p < 0.05). The 1-year fracture-free probability was 87.8% (95% CI, 78.2-97.4). On multivariate analysis, prior irradiation (HR, 7.30; 95% CI, 1.31-40.86) and pre-existing compression fracture (HR, 18.45; 95% CI, 3.42-99.52) were independent risk factors for VCF. CONCLUSION: The incidence of VCF following conventional RT to the spine is not particularly high, regardless of metastatic tumor involvement. Spines that received irradiation and/or have pre-existing compression fracture before RT have an increased risk of VCF and require close observation.
On the conflicts between biological and social evolution and between psychology and moral tradition.

Reports the APA Presidential address delivered at the Chicago convention, August 1975. Urban humanity is considered as a product of both biological and social evolution. Evolutionary genetics shows that when there is genetic competition among the cooperators (as for humans but not for the social insects), great limitations are placed upon the degree of socially useful, individually self-sacrificial altruism that biological evolution can produce. Human urban social complexity is a product of social evolution and has had to counter with inhibitory moral norms the biological selfishness which genetic competition has continually selected. Because the issues are so complex and the available data are so uncompelling, all of this should be interpreted more as a challenge to an important new area for psychological research than as established conclusions. It is emphasized, however, that these are important issues to which psychology should give much greater attention, and that scientific reasons exist for believing that there can be profound system wisdom in the belief systems our social tradition has provided us with. (31/2 p ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved)
Are Gamma-Ray Bursts in Star-Forming Regions?

The optical afterglow of the gamma-ray burst GRB 970508 (z=0.835) was a few hundred times more luminous than any supernova. Therefore, the name "hypernova" is proposed for the whole GRB/afterglow event. There is tentative evidence that the GRBs 970228, 970508, and 970828 were close to star-forming regions. If this case is strengthened with future afterglows, then the popular model in which GRBs are caused by merging neutron stars will have to be abandoned, and a model linking GRBs to cataclysmic deaths of massive stars will be favored. The presence of X-ray precursors, first detected with Ginga, is easier to understand within a framework of a "dirty" rather than a "clean" fireball. A very energetic explosion of a massive star is likely to create a dirty fireball rather than a clean one. A specific speculative example of such an explosion is proposed: a microquasar. Its geometrical structure is similar to the "failed supernova" of Woosley: the inner core of a massive, rapidly rotating star collapses into a ~10 M☉ Kerr black hole with ~5×1054 ergs of rotational energy, while the outer core forms a massive disk/torus. A superstrong ~1015 G magnetic field is needed to make the object operate as a microquasar similar to the Blandford & Znajek model. Such events must be vary rare, 104-105 times less common than ordinary supernovae, if they are to account for the observed GRBs.
Bruggeman approach for isotropic chiral mixtures revisited

Two interpretations of the Bruggeman approach for the homogenization of isotropic chiral mixtures are shown to lead to different results. Whereas the standard interpretation is shown to yield the average polarizability density approach, a recent interpretation turns out to deliver a null excess polarization approach. The difference between the two interpretations arises from differing treatments of the local field. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 524–527, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20685
Mach Wave Elimination in Supersonic Jets

Experimental results are presented on a method that eliminates Mach waves from the exhaust of supersonic jets and, hence, that removes a strong component of supersonic jet noise. Elimination is achieved by surrounding the jet with an annular stream at prescribed velocity and temperature so that all turbulent motions become intrinsically subsonic. No mechanical suppressors are used. Implementation of the technique in a typical turbofan engine is estimated to increase takeoff thrust with minimal impact on overall fuel consumption.
Spacecraft technology portfolio: Probabilistic modeling and implications for responsiveness and schedule slippage

Abstract Addressing the challenges of Responsive Space and mitigating the risk of schedule slippage in space programs require a thorough understanding of the various factors driving the development schedule of a space system. The present work contributes theoretical and practical results in this direction. A spacecraft is here conceived of as a technology portfolio. The characteristics of this portfolio are defined as its size (e.g., number of instruments), the technology maturity of each instrument and the resulting Technology Readiness Level (TRL) heterogeneity, and their effects on the delivery schedule of a spacecraft are investigated. Following a brief overview of the concept of R&D portfolio and its relevance to spacecraft design, a probabilistic model of the Time-to-Delivery of a spacecraft is formulated, which includes the development, Integration and Testing, and Shipping phases. The Mean-Time-To-Delivery (MTTD) of the spacecraft is quantified based on the portfolio characteristics, and it is shown that the Mean-Time-To-Delivery (MTTD) of the spacecraft and its schedule risk are significantly impacted by decreasing TRL and increasing portfolio size. Finally, the utility implications of varying the portfolio characteristics are investigated, and “portfolio maps” are provided as guides to help system designers identify appropriate portfolio characteristics when operating in a calendar-based design environment (which is the paradigm shift that space responsiveness introduces).
Old and Young X-Ray Point Source Populations in Nearby Galaxies

We have analyzed Chandra ACIS observations of 32 nearby spiral and elliptical galaxies and present the results of 1441 X-ray point sources that were detected in these galaxies. The total point-source X-ray (0.3-8.0 keV) luminosity LXP is well correlated with the B-band, K-band, and FIR+UV luminosities of spiral host galaxies and is well correlated with the B-band and K-band luminosities of elliptical galaxies. This suggests an intimate connection between LXP and both the old and young stellar populations, for which K and FIR+UV luminosities are reasonable proxies for the galaxy mass M and star formation rate SFR. We derive proportionality constants ? = 1.3 ? 1029 ergs s-1 M and ? = 0.7 ? 1039 ergs s-1 (M? yr-1)-1, which can be used to estimate the old and young components from M and SFR, respectively. The cumulative X-ray luminosity functions for the point sources have significantly different slopes. For the spiral and starburst galaxies, ? ? 0.6-0.8, and for the elliptical galaxies, ? ? 1.4. This implies that the most luminous point sources?those with LX 1038 ergs s-1?dominate LXP for the spiral and starburst galaxies. Most of the point sources have X-ray colors that are consistent with soft-spectrum (photon index ? ~ 1-2) low-mass X-ray binaries, accretion-powered black hole high-mass X-ray binaries (BH HMXBs), or ultraluminous X-ray sources (ULXs, also known as IXOs). We rule out hard-spectrum neutron star HMXBs (e.g., accretion-powered X-ray pulsars) as contributing much to LXP. Thus, for spirals, LXP is dominated by ULXs and BH HMXBs. We find no discernible difference between the X-ray colors of ULXs (LX ? 1039 ergs s-1) in spiral galaxies and point sources with LX ? 1038-1039 ergs s-1. We estimate that 20% of all ULXs found in spirals originate from the older (Population II) stellar populations, indicating that many of the ULXs that have been found in spiral galaxies are in fact Population II ULXs, like those in elliptical galaxies. We find that LXP depends linearly (within uncertainties) on both M and SFR for our sample galaxies (M 1011 M? and SFR 10 M? yr-1).
MODELING OF LASER-GENERATED RADIATIVE BLAST WAVES

We simulate experiments performed with the Falcon laser at Lawrence Livermore National Laboratory to generate strong, cylindrically diverging blast waves of relevance to astrophysics. In particular, we are interested in producing and modeling radiative shocks. We compare numerical simulations with the data and with an analytic approximation to blast-wave propagation with a radiative-loss term included. Our goal is to develop a laboratory setting for studying radiative shocks of relevance to supernova remnants, gamma-ray burst afterglows, and other high-energy astrophysics phenomena. We will show that a good degree of agreement exists between the experimental data and the numerical simulations, demonstrating that it is indeed possible to generate radiative shocks in the laboratory using tabletop femtosecond lasers. In addition, we show how we can determine the energy-loss rate from the blast-wave evolution. This analytic method is independent of the exact mechanism of radiative cooling and is scalable to both the laboratory and astrophysical radiative blast waves.
Indoor wayfinding: developing a functional interface for individuals with cognitive impairments.

Purpose. Assistive technology for wayfinding will significantly improve the quality of life for many individuals with cognitive impairments. The user interface of such a system is as crucial as the underlying implementation and localisation technology. We studied the user interface of an indoor navigation system for individuals with cognitive impairments.Method. We built a system using the Wizard-of-Oz technique that let us experiment with many guidance strategies and interface modalities. Through user studies, we evaluated various configurations of the user interface for accuracy of route completion, time to completion, and user preferences. We used a counter-balanced design that included different modalities (images, audio, and text) and different routes.Results. We found that although users were able to use all types of modalities to find their way indoors, they varied significantly in their preferred modalities. We also found that timing of directions requires careful attention, as does providing user...
Supersonic Inflatable Aerodynamic Decelerators for Use On Future Robotic Missions to Mars

The 2009 Mars science laboratory mission is being designed to place an 850 kg rover on the surface of Mars at an altitude of at least one kilometer. This is being accomplished using the largest aeroshell and supersonic parachute ever flown on a Mars mission. Future missions seeking to place more massive payloads on the surface will be constrained by aeroshell size and deployment limitations of supersonic parachutes. Inflatable aerodynamic decelerators (IADs) represent a technology path that can relax those constraints and provide a sizeable increase in landed mass. This mass increase results from improved aerodynamic characteristics that allow IADs to bedeployed at higher Mach numbers and dynamic pressures than can be achieved by current supersonic parachute technology.During the late 1960's and early 1970's preliminary development work on IADs was performed. This included initial theoretical shape and structural analysis for a variety of configurations as well as wind tunnel and atmospheric flight tests for a particular configuration, the attached inflatable decelerator (AID). More recently, the program to advance inflatable decelerators for atmospheric entry (PAI-DAE) has been working to mature a second configuration, the supersonic tension cone decelerator, for use during atmospheric entry.This paper presents an analysis of the potential advantages of using a supersonic IAD on a proposed 2016 Mars mission. Conclusions drawn are applicable to both the astrobiology field laboratory and Mars sample return mission concepts. Two IAD configurations, the AID and tension cone, are sized and traded against their system-level performance impact. Analysis includes preliminary aerodynamic drag estimates for the different configurations,trajectory advantages provided by the IADs, and preliminary geometric and mass estimates for the IAD subsystems. Entry systems utilizing IADs are compared against a traditional parachute system as well as a system employing an IAD in the supersonic regime and a parachute in the subsonic regime. Key sensitivities in IAD design are included to highlight areas of importance in future technology development programs.
Structure of Magnetic Tower Jets in Stratified Atmospheres

Based on a new approach on modeling the magnetically dominated outflows from AGNs (Li et al. 2006), we study the propagation of magnetic tower jets in gravitationally stratified atmospheres (such as a galaxy cluster environment) in large scales (> tens of kpc) by performing three-dimensional magnetohydrodynamic (MHD) simulations. We present the detailed analysis of the MHD waves, the cylindrical radial force balance, and the collimation of magnetic tower jets. As magnetic energy is injected into a small central volume over a finite amount of time, the magnetic fields expand down the backgroun d density gradient, forming a collimated jet and an expanded “lobe” due to the gradually decreasing background density and pressure. Both the jet and lobes are magnetically dominated. In addition, the injection and expansion produce a hydrodynamic shock wave that is moving ahead of and enclosing the magnetic tower jet. This shock can eventually break the hydrostatic equilibrium in the ambient medium and cause a global gravitational contraction. This contraction produces a strong compression at the head of the magnetic tower front and helps to collimate radially to produce a slendershaped jet. At the outer edge of the jet, the magnetic pressur e is balanced by the background (modified) gas pressure, without any significant contribution from the hoo p stress. On the other hand, along the central axis of the jet, hoop stress is the dominant force in shaping the cent ral collimation of the poloidal current. The system, which possesses a highly wound helical magnetic configurati on, never quite reaches a force-free equilibrium state though the evolution becomes much slower at late stages. The simulations were performed without any initial perturbations so the overall structures of the jet r emain mostly axisymmetric. Subject headings:magnetic fields — galaxies: active — galaxies: jets — methods : numerical — magnetohydrodynamics (MHD)
Reflection and Transmission Imaging of the Upper Crust Using Local Earthquake Seismograms

We utilize the characteristic features of primary P - and SH -wave coda and Sp waveforms from local microearthquake data and perform prestacking 1D migration in an attempt to image prominent reflectors in the upper crust of the New Madrid seismic zone (NMSZ). This methodology applies to data from broadband stations, PARM and PENM, of the Cooperative New Madrid Seismic Network (CNMSN). Nearby exploration well log acoustic data of the Wilson 2-14 and Dow Chemical/Wilson number 1 wells are used to constrain the upper 4 km of P -wave velocity model. Despite polarity differences among P , SH , and Sp waveforms, this technique demonstrates that consistent reflectors in the deep sedimentary section can be imaged commonly among the three wave types. There are excellent correlations associated with the base of the upper Cretaceous/Holocene Mississippi Embayment Supergroup and the base of Knox group, which were also reported in a study of nearby seismic-reflection profiles by Hamilton and Zoback (1982). The Bonne Terre formation seems to be a prominent seismic stratigraphic marker associated with an interface displayed in the profiling. We find that earthquake event S - P times must be ∼3 sec or more to resolve reflectors at about 4 km depth. Possible basement at about 4.0 to 4.5 km appears on the reflected P -wave image for PARM and SH -wave image for PENM. We conclude that the velocity structure of the upper 4 km crust beneath PARM can be represented by a constant velocity of ![Graphic][1] and ![Graphic][2] for the unconsolidated sediments and ![Graphic][3] and ![Graphic][4] for the Paleozoic sedimentary rocks. A constant velocity of ![Graphic][5] and ![Graphic][6] for the unconsolidated sediments and ![Graphic][7] and ![Graphic][8] for the Paleozoic sedimentary rocks can represent structure beneath PENM. [1]: /embed/inline-graphic-1.gif [2]: /embed/inline-graphic-2.gif [3]: /embed/inline-graphic-3.gif [4]: /embed/inline-graphic-4.gif [5]: /embed/inline-graphic-5.gif [6]: /embed/inline-graphic-6.gif [7]: /embed/inline-graphic-7.gif [8]: /embed/inline-graphic-8.gif
Postglacial rebound observed by lageos and the effective viscosity of the lower mantle

Sixty-four observations of the orbital node made by the Lageos satellite over a five year time interval reveal an acceleration of (-8.1 + or - 1.8) x 10 to the -8 power arcseconds day/2 due to a source which is not presently modeled in the GEODYN orbit determination computer program. This acceleration cannot be explained by the ocean tide with 18.6 year period, assuming it to be an equilibrium tide. Instead it seems to be due to postglacial rebound, which changes the J(2) coefficient in the spherical harmonic expansion of the earth's gravitational field at the rate of (-8.2 + or - 18) x 10 to the -19th power/s; this in turn accelerates the node. This rate does not agree with the -32 x 10 to the -19th power/s predicted by Wu and Peltier's (1982) L2 model, which has upper and lower mantle effective viscosities of 10 to the 21st and 22nd powers Pa's, respectively. It does agree well with their L1 model, which gives about 10 x 10 to the 19th power/s. Since the effective viscosity is 10 to the 21st power Pa s throughout the entire mantle in the L1 model, the results support the contentions that the efective viscosity is near 10 to the 21st power Pa s everyhere in the mantle, and this relatively low value for the effective viscosity may have permitted several degrees of polar wander due to glaciation during the Quaternary Ice Age. Previously announced in STAR as N84-13705
On balanced games and games with committee control

A generalization of flow games, namely, flow games with committee control is considered, to obtain a representation of non-negative balanced games. The committee control is modeled with the aid of simple games. Linear production games with committee control are also studied and results on the balancedness of such games are obtained.
Mid-Infrared Interband Cascade Lasers for Free-Space Laser Communication

We have fabricated high-speed Interband Cascade lasers and provided the first experimental evidence that these devices can be directly modulated at a frequency of 3.2 GHz and above. This work has demonstrated suitability of IC lasers as a mid-IR light source for multi-GHz free space optical communications links.
Electrocoagulation and curettage for carcinoma involving the skin of the face, nose, eyelids, and ears.

Electrocoagulation and curettage has been criticized as inadequate therapy for skin carcinoma. This series of patients demonstrates the effectiveness of electrocoagulation and curettage in the treatment of carcinoma involving the skin of the head and face. From 1964 through 1968, 90 private patients with 128 skin cancers of the head and face were treated by electrocoagulation and curettage. Approximately 50% of these patients were more than 70 years old; 93% of the lesions were basal cell carcinomas and 39% involved the skin of the nose, eyelids, or ears. Forty-four per cent were at least 1 cm or greater in transverse diameter. Only one patient required hospitalization for this therapy, and all lesions were destroyed under local anesthesia. The average healing time was 5.1 weeks. There was neither morbidity nor mortality related to this therapy. All patients were personally followed from 2-7 years. Complete cure was observed in 93% of these lesions. The recurrence rate for 123 primary (previously untreated) skin cancers was 6.5%. Recurrence is first noticed on the scar created by the initial coagulation and is easily recoagulated. These data emphasize the simplicity and adequacy of this treatment modality. In addition, electrocoagulation and curettage is convenient, expeditious, and economical, important assets in these times of burgeoning hospital costs. It is well tolerated by cartilage, and cartilage necrosis has not been observed. Electrocoagulation is tissue-sparing—of great importance in the nose, eye, and ear areas. It avoids anesthetic risks, extensive surgical procedures, prolonged hospitalization, and multiple treatment visits. These considerations justify its use as the preferred therapy of skin cancer of the head and face.
Non-LTE and gradient effects in K-shell oxygen emission laser-produced plasma

Abstract A recent effort [1] to develop a high-resolution spectroscopy capability for He-like and H-like ions to study far wing shapes from a laser-produced plasma experiment at the Lawrence Livermore National Laboratory found unexpected structure in the observed emission from a Mylar target. In this paper we propose that the observed features are due to exotic inner-shell transitions in mid-ionized oxygen, suggesting that the observed emission arises from two plasma regions: a hotter, less dense outer region gives rise to the observed He-like and H-like resonance lines, while a cooler, more dense plasma region closer to the target surface and in a region surrounding the laser spot generates the dielectronic satellites and the exotic inner-shell lines. Calculations using the Los Alamos suite of atomic physics codes and the plasma kinetics code ATOMIC are used to support this assertion.
POLYGONAL APPROXIMATION AND ENERGY OF SMOOTH KNOTS

We establish a fundamental connection between smooth and polygonal knot energies, showing that the Minimum Distance Energy for polygons inscribed in a smooth knot converges to the Mobius Energy of the smooth knot as the polygons converge to the smooth knot. For this to work, the polygons must converge in a "nice" way, and the energies must be correctly regularized. We determine an explicit error bound for the convergence.
Microstructure and Dielectric Characteristics of (PbxBa0.5−xSr0.5)TiO3 Ceramics

Microstructural and dielectric properties of the PbxBa0.5_x—Sr0.5TiO3 system have been studied. It is found that this system forms a solid solution in the entire composition range (0.0≤x≤0.5) and is cubic for the x= 0, 0.1, and 0.2 compositions and tetragonal for other compositions. Measurements of the dielectric constant as a function of temperature reveal that this material is ferroelectric at room temperature for the x > 0.2 compositions and has a broad paraelectric-ferroelectric transition region. No shift in the dielectric maxima was noted; however, there is a slight spread in the dielectric constant with frequency for the x= 0.4 composition. A quantitative model to mathematically analyze the effect of composition fluctuations on the dielectric broadening for a ternary system is presented. Transmission electron microscopic studies reveal the presence of 90° ferroelectric domains oriented along the {01} planes for the x= 0.3 and 0.4 compositions.
Molecular Clouds in the Galaxy

Millimeter-wave observations of the CO molecule have proved, over the past decade, to be the most important probe of molecular hydrogen and star-forming regions in the Galaxy. Molecular hydrogen, H2, has no dipole moment or radio transitions and is largely unobservable except in those regions that are shock heated (to temperatures > 1000K) to produce quadrupole vibrational-rotational emission. Observations of H2 absorption lines in the ultraviolet are necessarily limited to clouds with very small extinction and thus small H2 column densities. For these reasons, information on the physics, kinematics, Galactic distribution, and even the existence of massive star-forming clouds must come from emission lines of minor constituents, especially, but not exclusively, CO and its isotopic variants.
Determinantal probability measures

Determinantal point processes have arisen in diverse settings in recent years and have been investigated intensively. We study basic combinatorial and probabilistic aspects in the discrete case. Our main results concern relationships with matroids, stochastic domination, negative association, completeness for infinite matroids, tail triviality, and a method for extension of results from orthogonal projections to positive contractions. We also present several new avenues for further investigation, involving Hilbert spaces, combinatorics, homology, and group representations, among other areas.
A new determination of Jupiter's radio rotation period

The result of a measurement of the period of rotation of Jupiter's inner magnetosphere with unprecendented precision is presented. The measurement was made from the University of Florida database of 35 apparitions of Jovian decametric observations at frequencies of 18, 20, and 22 MHz between 1957 and 1994. The mean of our 24 independent measurements was 9h55m29s.685, and the standard deviation of the mean was 0s.0034. The System III (1965) Jovian rotation period value that is currently accepted by the International Astronomical Union is greater than our value by 7.4 times our standard deviation; it appears to be in need of revision. We set an upper limit of 27 milliseconds per year on a possible drift of the rotation period as measured by our method.
Hydrodynamics of the Stream-Disk Impact in Interacting Binaries

We use hydrodynamic simulations to provide quantitative estimates of the effects of the impact of the accretion stream on disks in interacting binaries. For low accretion rates, efficient radiative cooling of the hotspot region can occur, and the primary consequence of the stream impact is stream overflow toward smaller disk radii. The stream is well described by a ballistic trajectory, but larger masses of gas are swept up and overflow at smaller, but still highly supersonic, velocities. If cooling is inefficient, overflow still occurs, but there is no coherent stream inward of the disk rim. Qualitatively, the resulting structure appears as a bulge extending downstream along the disk rim. We calculate the mass fraction and velocity of the overflowing component as a function of the important system parameters, and discuss the implications of the results for X-ray observations and Doppler tomography of cataclysmic variables, low-mass X-ray binaries, and supersoft X-ray sources.
Koszulity and the Hilbert series of preprojective algebras

The goal of this paper is to prove that if Q is a connected non-Dynkin quiver then the preprojective algebra of Q over any field k is Koszul, and has Hilbert series 1/(1-Ct+t^2), where C is the adjacency matrix of the double of Q. (This result, in somewhat less general formulations, was previously obtained by Martinez-Villa and Malkin-Ostrik-Vybornov). We also prove a similar result for the partial preprojective algebra of any connected quiver Q, associated to a subset J of the set I of vertices of Q (by definition, this is the quotient of the path algebra of the double by the preprojective algebra relations imposed only at vertices not contained in J). Namely, we show that if J is not empty then this algebra is Koszul, and its Hilbert series is 1/(1-Ct+D_Jt^2), where D_J is the diagonal matrix with (D_J)_{ii}=0 if i is in J and (D_J)_{ii}=1 otherwise. Finally, we show that both results are valid in a slightly more general framework of modified preprojective algebras.
Teacher and students’ joint production of a reversible fraction conception

Abstract Within a constructivist perspective, I conducted a teaching experiment with two fourth graders to study how a teacher and students can jointly produce the reversible fraction conception. Ongoing and retrospective analysis of the data revealed the non-trivial process by which students can abstract multiplicative reasoning about fractions. The study articulates a conception in a developmental sequence of iteration-based fraction conceptions and the teacher’s role in fostering such a conception in students.
High-level ab initio thermochemical data for halides of chromium, manganese, and iron.

The thermochemistry of the transition-metal fluorides and chlorides MF{sub n} and MCl{sub n} (M = Cr, Mn, Fe; n = 1, 2) has been characterized by high-level ab initio electronic structure methods. Geometries and harmonic vibrational frequencies were computed at the B3LYP level of theory using triple-{zeta} basis sets including diffuse and polarization functions. Heats of formation were computed from isogyric reaction energies at the CCSD(T) level using high-quality basis sets, including corrections for core-valence correlation and scalar relativistic effects. To investigate the possible linearity of the ground states of CrCl{sub 2} and CrF{sub 2}, we performed geometry optimizations for these species at the CCSD(T) level using large basis sets. In both cases, a bent ({sup 5}B{sub 2}) minimum structure was located, but the bent structure is only slightly below the linear form, which was found to be a transition state. For all of the investigated halides, polynomial fits were carried out for the heat capacity and the standard enthalpy and entropy in the 300-3000 K temperature range.
Evolutionary psychology and consumer behavior: A constructive critique

We examine the theoretical basis for the evolutionary narrative common to the target papers by Saad (this issue) and by Griskevicius and Kenrick (this issue) and identify areas of controversy that have sparked debate about evolutionary psychology [EP] among biologists and behavioral ecologists. The two main areas of disagreement are over (1) the role of genetic adaptations resulting from natural selection in ancient times compared to other forces leading to current behavior; and (2) the likelihood that evolution resulted in a set of highly specialized mental modules or information-processing circuits thought to be instrumental in determining present-day behavior. We review the EP research discussed by the authors of the target papers as a means of evaluating the evidence in support of the theory and of suggesting future directions of research.
Aeroacoustics of Axisymmetric Single- and Dual-Flow Exhaust Nozzles

A systematic approach to the prediction of jet noise has been developed for conical, conventional bypass, and inverted-flow bypass nozzles. The prediction involves computation of the mean velocity, temperature, and relevant turbulence properties throughout the jet. Each turbulent eddy volume in the jet is treated as a statistically independent radiator of sound embedded in the mean-flowfield. The acoustic/mean-flow interaction is computed from high-frequency asymptotic solutions to Lilley's wave equation. Extensive theory-data comparisons indicate that acoustic/mean-flow interaction plays an important role, and that the prediction method can account for most of the observed characteristics of single- and dual-flow jets.
Accounting-Based Stock Price Anomalies: Separating Market Inefficiencies from Risk*

Abstract. We examine six accounting-based stock price anomalies using two sets of tests to determine the extent to which the anomalies (1) represent market mispricing or (2) reflect premia for unidentified risks. Market mispricing is indicated if the anomalous returns are concentrated around subsequent earnings announcements in patterns suggesting that the earnings information causes traders to re-examine their prior (incorrect) beliefs. Mispricing is also indicated if anomalous returns on zero-investment portfolios are positive, period after period. Our results indicate that an anomaly based on earnings momentum probably reflects market mispricing, but that two value-glamour anomalies (based on the book-market ratio and the earnings-price ratio), and two anomalies based on computerized fundamental analyses (from Ou and Penman 1989 and Holthausen and Larcker 1992) are more likely to reflect risk premia than indicated by prior research. Evidence on a sixth anomaly, based on price momentum, is mixed.
Study of Very Short Gamma-Ray Bursts

We have carried out a detailed study of the morphology of gamma-ray bursts (GRBs) with time duration less than 100 ms that includes the following: (1) a fast-Fourier spectrum analysis, (2) a comparison with the Stern analysis of longer bursts, (3) an inner comparison of the properties of the short bursts, and (4) a comparison of the short burst properties with the bulk of the GRBs from the Burst and Transient Source Experiment (BATSE) 4B catalog. We have used the time tagged event (TTE) BATSE 3B data, which is available to the public, for part of the analysis. We show that these bursts are very different from the rest of the GRB events. The short bursts appear to be nearly identical, suggesting a separate class of GRBs. We also show that the short bursts have a Euclidean spacetime distribution, in sharp contrast to the longer bursts with τduration >100 ms that implies that these sources are likely local. Finally we compare the bursts with a model of primordial black hole (PBH) evaporation at the quark-gluon (Q-G) phase transition temperature and other shock wave models.
B physics at CDF - the Beauty of hadron collisions

The CDF experiment at the Tevatron p{bar p} collider established that extensive and detailed exploration of the b-quark dynamics is possible in hadron collisions, with results competitive and supplementary to those from e{sup +}e{sup -} colliders. This provides an unique, rich, and highly rewarding program that is currently reaching full maturity. I report a few recent world-leading results on rare decays, CP-violation in B{sub s}{sup 0} mixing, and b {yields} s penguin decays.
A New Water-Soluble Near-Neutral Ratiometric Fluorescent pH Indicator

We report a new near-neutral pH indicator whose pKa of ~7.0 was determined by both absorption and fluorescence methods. It has a distinctive isoemissive point, good dispersion in cell cytosol, and low cytotoxicity.
Transparency, Efficiency and the Distribution of Economic Welfare in Pass-Through Investment Trust Games *

We design an experiment to examine behavior and welfare in a multi-level trust game representing a pass through investment in an intermediated market. In a repeated game, an investor invests via an intermediary who lends to a borrower. A pre-experiment one-shot version of the game serves as a baseline and to type each subject. We alter the transparency of exchanges between non-adjacent parties. We find transparency of the exchanges between the investor and intermediary does not significantly affect welfare. However, transparency regarding exchanges between the intermediary and borrower promotes trust on the part of the investor, increasing welfare. Further, this has asymmetric effects: borrowers and intermediaries achieve greater welfare benefits than investors. We discuss implications for what specific aspects of financial market transparency may facilitate more efficiency.