cssi/SciSciGPT-SciSciNet huggingface dataset:
Abundance of condensable species at planetary cold traps: The role of moist convection

The interplay of moist convection and particle growth in the tropopause region of the atmospheres of earth, Uranus, and Neptune has been investigated. It is found that the downward flux of aerosols is not sufficient to dehydrate the earth's stratosphere by chemical dessication, and that the source of Neptune's oversaturated stratosphere is convective penetration of the tropopause by moist convective columns of methane. It is shown that conditions in the troposphere of Uranus are not conducive to the initiation of moist convection.
Synthetic studies relating to the C1–C9 “Eastern” Half of Rosaramicin

Abstract A pyranodisic homologation approach to the “eastern half” of rosaramicin is described. The synthetic plan calls for two one-carbon chain extensions, but these occur at “off-template” sites where asymmetric centers are neither destroyed nor created. However, these one-carbon displacements pose special unexpected difficulties and procedures for overcoming these are described.
Speed sensorless vector torque control of induction machines using a two-time-scale approach

Conditions for observability of a linearized smooth-airgap induction machine model are examined, and limitations of any speed-sensorless observer scheme based on such a model are discussed. An approach for speed-sensorless flux estimation based on singular perturbation theory is developed. This approach relies on the natural time-scale separation between the electrical and mechanical dynamics of the induction machine. A full-order observer of an induction machine is presented, incorporating a correction term which has an intuitive explanation when one considers steady-state stator currents. Using singular perturbation theory, convergence of the observer is shown for all open-loop stable operating points of the induction machine, with the exception of DC excitation. Sensitivity of the observer to parameter deviations is discussed. Experimental results are presented confirming the validity of the above approach.
Characterization of diastereomers by 31P{1H} NMR spectroscopy

Abstract Many of the more efficient transition-metal catalysts for enantioselective synthesis of organic compounds contain chiral organophosphorus ligands. Phosphorus-31 nuclear magnetic resonance spectroscopic data are given in this review for several representative types of diastereomers that have been of aid in the determination of optical purity and in the study of reaction mechanisms.
Extending the mathematics in qualitative process theory

Reasoning about physical systems requires the integration of a range of knowledge and reasoning techniques. P. Hayes has named the enterprise of identifying and formalizing the common-sense knowledge people use for this task “naive physics.” Qualitative Process theory by K. Forbus proposes a structure and some of the content of naive theories about dynamics, (i.e., the way things change in a physical situation). Any physical theory, however, rests on an underlying mathematics. QP theory assumes a qualitative mathematics which captures only simple topological relationships between values of continuous parameters. While the results are impressive, this mathematics is unable to support the full range of deduction needed for a complete naive physics reasoner. A more complete naive mathematics must be capable of representing measure information about parameter values as well as shape and strength characterizations of the partial derivatives relating these values. This article proposes a naive mathematics meeting these requirements, and shows that it considerably expands the scope and power of deductions which QP theory can perform. © 1989 Wiley Periodicals, Inc.
Sphere Packings, II

An earlier paper describes a program to prove the Kepler conjecture on sphere packings. This paper carries out the second step of that program. A sphere packing leads to a decomposition of ℝ3 into polyhedra. The polyhedra are divided into two classes. The first class of polyhedra, called quasi-regular tetrahedra, have density at most that of a regular tetrahedron. The polyhedra in the remaining class have density at most that of a regular octahedron (about 0.7209).
Forging the Solution to the Energy Challenge: The Role of Materials Science and Materials Scientists

The energy challenge is central to the most important strategic problems facing the United States and the world. It is increasingly clear that even large-scale deployments of the best technologies available today cannot meet the rising energy demands of a growing world population. Achieving a secure and sustainable energy future will require full utilization of, and substantial improvements in, a comprehensive portfolio of energy systems and technologies. This goal is complicated by several factors. First, energy strategies are inextricably linked to national security and health issues. Second, in developing and deploying energy technologies, it is vital to consider not only environmental issues, such as global climate change, but also economic considerations, which strongly influence both public and political views on energy policy. Third, a significant and sustained effort in basic and applied research and development (R&D) will be required to deliver the innovations needed to ensure a desirable energy future. Innovations in materials science and engineering are especially needed to overcome the limits of essentially all energy technologies. A wealth of historical evidence demonstrates that such innovations are also the key to economic prosperity. From the development of the earliest cities around flint-trading centers, to the Industrial Revolution, to today’s silicon-based global economy, the advantage goes to those who lead in exploiting materials. I view our challenge by considering the rate of innovation and the transition of discovery to the marketplace as the relationship among R&D investment, a skilled and talented workforce, business innovations, and the activities of competitors. Most disturbing in analyzing this relationship is the need for trained workers in science, technology, engineering, and mathematics (STEM). To develop the STEM workforce needed for innovation, we need sustainable, positive change in STEM education at all levels from preschool through postgraduate. Materials sciences can be a significant magnet in attracting students to STEM areas, and a focused effort is needed to ensure that it is included in STEM programs. From this effort will come the next generation of materials scientists and the innovations that will enable us to overcome the energy challenge.
Toward a quantitative near-bottom seismic profiler

Abstract This paper describes the development and application of a system for quantitative near-bottom seismic profiling at 4 kHz. Developed as part of the Deep Tow Instrumentation System of the Marine Physical Laboratory, this system represents a capability which is relatively unique in terms of lateral resolution. This capability was developed in order to observe small-scale horizontal variations in acoustic reflectivity of the sea floor as well as similar properties for shallow, layered structures in bottom sediments. The system provides real time computer processing and quantitative displays of processed data in several forms. These displays include a high resolution grey scale display of equivalent plane wave pressure (compensating for Fish altitude), a three-dimensional contourogram display of equivalent intensity, and a plot of integrated equivalent energy for travel-time sections (typically corresponding to 0–5 and 5–55 m into the bottom). These quantitative displays provide a real-time capability for mapping reflectivity of the sea floor and sub-bottom reflectors within a survey area and for estimating acoustic attenuation in marine sediments from observations of layer reflectivity as a function of depth of burial. Such determinations of attenuation can be made directly from the composite computer display which is produced on a facsimile recorder. The data from this system suggest that small scale variations are common to many areas of the sea floor, with poorly explained variations of up to 10 dB over lateral distances of less than 50 m. Values of effective attenuation determined by this system show good agreement with values measured directly in the San Diego Trough, and suggest unusually low values for highly calcareous sediments on the Carnegie Ridge.
The Dynamic Impact of Macro Shocks on Insurance Premiums

We develop a model that investigates the relation between insurance premiums and macroeconomic variables, including oil price, interest rate, aggregate supply, and aggregate demand. We then use a multivariate structural vector error correction model to distinguish the effects arising from permanent and transitory components of insurance premiums. Changes in the transitory component indicate that our model captures key historical events. Although real shocks originating from oil price and aggregate supply explain the behavior of insurance premiums well, we show that financial market shocks are the main driving force behind the recent increasing volatility in insurance premiums in the U.S. market.
Epilepsy and respiratory chain defects in children with mitochondrial encephalopathies.

Objective: The purpose of this study was to determine the relationship between epilepsy and respiratory chain defects in children with mitochondrial encephalopathies (ME). Study Design: We conducted a retrospective review of the medical records of children referred for evaluation of an ME. Only patients assigned a definite diagnosis of ME using modified Walker criteria and with a respiratory chain defect were included. Clinical data pertaining to the ME and epilepsy type were collected. Mitochondria were isolated by subcellular fractionation from a vastus lateralis muscle biopsy and studies were performed using polarographic and spectroscopic techniques for the quantitative determination of NADH and cytochrome components of the respiratory chain. Results: A total of 38 children with ME were identified. Seizures were present in 61%. Sixteen of 23 children with epilepsy (70%) had refractory epilepsy associated with a progressive encephalopathy. Children with epilepsy had a significantly higher incidence of complex I defects than children without epilepsy (p<0.01). Complex III and IV defects were significantly higher in patients without epilepsy (p<0.01 and p<0.05, respectively) than in those with epilepsy. Conclusions: Epilepsy is an important component of ME. The higher incidence of complex I defects in patients with epilepsy suggests a possible relationship between mitochondrial oxidative stress dysfunction and epileptogenic process.
Stereoselective Isoxazolidine Synthesis Via Copper-Catalyzed Alkene Aminooxygenation

Isoxazolidines are useful in organic synthesis, drug discovery, and chemical biology endeavors. A new stereoselective synthesis of methyleneoxy-substituted isoxazolidines is disclosed. The method involves copper-catalyzed aminooxygenation/cyclization of N-sulfonyl-O-butenyl hydroxylamines in the presence of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl radical (TEMPO) and O2 and provides substituted isoxazolidines in excellent yields and diastereoselectivities. We also demonstrate selective mono N–O reduction followed by oxidation of the remaining N–O bond to reveal a 2-amino-γ-lactone. Reduction of the γ-lactone reveals the corresponding aminodiol.
Effects Of Coherence In Radiometry

Radiometry evolved over a long period of time around rather in-coherent sources of thermal nature. Only during the last few years have the effects of coherence begun to be taken into account in radiometric considerations of light sources. In this review article the fundamental concepts of conventional radiometry and of the theory of partial coherence will be first briefly recalled. The basic radiometric quantities, namely the radiance, the radiant emittance, and the radiant intensity, associated with a planar source of any state of coherence will then be introduced. It will be pointed out that the radiant intensity, representing the primary measurable quantity, obeys in all circumstances the usual postulates of conventional radiometry, whereas the radiance and the ra-diant emittance turn out to be much more elusive concepts. The radiometric characteristics of light from incoherent and coherent sources as well as from a certain type of partially coherent source, viz., the so-called quasihomogeneous source, will be analyzed. Quasihomogeneous sources are useful models for radiation sources that are usually found in nature. Lambertian sources will be discussed as examples.
Building on experience: lessons from a distance education M.S.W program

SUMMARY Using data from interviews with students completing the first half of an entire M.S.W. degree program delivered through distance education and a comparable group of students on the main campus, this paper focuses on many of the key issues asked about electronically mediated graduate education in social work: positive and negative aspects of the program; costs and benefits of participation; and overall perspectives on students' experiences.
Measuring the Galaxy Cluster Bulk Flow from WMAP data

We have looked for bulk motions of galaxy clusters in the Wilkinson Microwave Anisotropy Probe (WMAP) seven-year data. We isolate the kinetic Sunyaev-Zeldovich (SZ) signal by filtering the WMAP Q-, V-, and W-band maps with multi-frequency matched filters that utilize the spatial properties of the kinetic SZ signal to optimize detection. We try two filters: a filter that has no spectral dependence, and a filter that utilizes the spectral properties of the kinetic and thermal SZ signals to remove the thermal SZ bias. We measure the monopole and dipole spherical harmonic coefficients of the kinetic SZ signal, as well as the l = 2-5 modes, at the locations of 736 ROSAT observed galaxy clusters. We find no significant power in the kinetic SZ signal at these multipoles with either filter, consistent with the {Lambda}CDM prediction. Our limits are a factor of {approx}3 more sensitive than the claimed bulk flow detection of Kashlinsky et al. Using simulations we estimate that in maps filtered by our matched filter with no spectral dependence there is a thermal SZ dipole that would be mistakenly measured as a bulk motion of {approx}2000-4000 km s{sup -1}. For the WMAP data, the signal-to-noise ratio obtained with themore » unbiased filter is almost an order of magnitude lower.« less
ORFEUS II and IUE Spectroscopy of EX Hydrae

Using five high-resolution (λ/Δλ ≈ 3000) FUV (910-1210 A) spectra acquired in 1996 December during the flight of the ORFEUS-SPAS II mission, 47 archival IUE short-wavelength UV (1150-1950 A) spectra, and archival EUVE deep survey photometry (70-200 A), we present a detailed picture of the behavior of the magnetic cataclysmic variable EX Hydrae in the vacuum ultraviolet. Like Hopkins Ultraviolet Telescope spectra of this source, these far-ultraviolet (FUV) and UV spectra reveal broad emission lines of He II, C II-CIV, N III and N V, O VI, Si III-S IV, and Al III superposed on a continuum that is blue in the UV and nearly flat in the FUV. Like ORFEUS spectra of AM Her, the O VI λλ1032, 1038 doublet is resolved into broad (FWHM ≈ 2000 km s-1) and narrow (FWHM ≈ 200 km s-1) emission components. Consistent with its behavior in the optical, and hence consistent with the accretion curtain model of this source, the FUV and UV continuum flux densities, the FUV and UV broad emission-line fluxes, and the radial velocity of the O VI broad emission component all vary on the spin phase of the white dwarf, with the maximum of the FUV and UV continuum and broad emission line flux light curves coincident with maximum blueshift of the broad O VI emission component. On the binary phase, the strong eclipse of the EUV flux by the bulge on the edge of the accretion disk is accompanied by narrow and relatively weak absorption components of the FUV emission lines and 30%-40% eclipses of all the UV emission lines except He II λ1640, while the UV continuum is largely unaffected. Furthermore, both the flux and radial velocities of the O VI narrow emission component vary with binary phase. The relative phasing of the FUV and UV continuum light curves and the FUV emission-line radial velocities implicate the accretion funnel as the source of the FUV and UV continuum and the O VI broad emission component and implicate the white dwarf as the source of the O VI narrow emission component. Various lines of evidence imply that the density of both the broad- and narrow-line regions is n 1011 cm-3, but the O VI line ratios imply that the narrow-line region is optically thick, while the broad-line region is more likely optically thin.
Topographic Mapping of the Moon

Contour maps of the moon have been compiled by photogrammetric methods that use stereoscopic combinations of all available metric photographs from the Apollo 15, 16, and 17 missions. The maps utilize the same format as the existing NASA shaded-relief Lunar Planning Charts (LOC-1, -2, -3, and -4), which have a scale of 1:2,750,000. The map contour interval is 500 m. A control net derived from Apollo photographs by Doyle and others was used for the compilation. Contour lines and elevations are referred to the new topographic datum of the moon, which is defined in terms of spherical harmonics from the lunar gravity field. Compilation of all four LOC charts was completed on analytical plotters from 566 stereo models of Apollo metric photographs that cover approximately 20 percent of the moon. This is the first step toward compiling a global topographic map of the moon at a scale of 1:5,000,000.
Recent Advances in Chemical Synthesis, Self‐Assembly, and Applications of FePt Nanoparticles

This paper reviews recent advances in chemical synthesis, self-assembly, and potential applications of monodisperse binary FePt nanoparticles. After a brief introduction to nanomagnetism and conventional processes of fabricating FePt nanoparticles, the paper focuses on recent developments in solution-phase syntheses of monodisperse FePt nanoparticles and their self-assembly into nanoparticle superlattices. The paper further outlines the surface, structural, and magnetic properties of the FePt nanoparticles and gives examples of three potential applications in data storage, permanent magnetic nanocomposites, and biomedicine.
Local orbital debris flux study in the geostationary ring

Abstract A local orbital debris flux analysis is performed in the geostationary (GEO) ring to investigate how frequently near-miss events occur for each longitude slot in the GEO ring. The current resident space object (RSO) environment at GEO is evaluated, and publicly-available two-line element (TLE) data are utilized in tandem with a geostationary torus configuration to simulate near-miss events incurred by the trackable RSO population at GEO. Methodology for determining near-miss events with this formulation is introduced, and the results of the analysis for a one-year time frame are provided to illustrate the need for active GEO remediation.
Exporting, capital investment and financial constraints

Many firms cite financial constraints as some of the most important impediments to their investment and growth. Using a unique data set from the Czech Republic this paper investigates the importance of financing constraints in the context of exporters. It finds that exporters are less financially constrained than non-exporters. However, after carefully correcting for possible endogeneity and selection issues, the evidence points to less constrained firms self-selecting into exporting rather than exporting alleviating firms’ financial constraints.
Judicial checks on corruption in the United States

Judicial oversight provides an important check on executive and legislative power. Two components of judicial oversight have been identified in the literature: judicial independence and constitutional review. Recent research using country-level data indicates that the effectiveness of constitutional review is largely determined by the rigidity of the constitution. In this paper, I use state-level data to test whether judicial independence and constitutional rigidity are related to a specific type of abuse of power by government officials: corruption in office. Specifically, I fit negative binomial regressions in which the dependent variable is the number of officials convicted for corrupt acts and the independent variables are (i) measures of judicial independence, such as judges’ remuneration, method of appointment, and term length, along with various controls or (ii) measures of constitutional rigidity, such as legislative majorities required to propose constitutional amendments and provisions for constitutional conventions or constitutional initiatives, along with various controls. I find that, in general, states with higher levels of judicial independence and more rigid constitutions have lower levels of corruption per capita than states with the opposite characteristics.
Superpotentials for Quiver Gauge Theories

We compute superpotentials for quiver gauge theories arising from marginal D-Brane decay on collapsed del Pezzo cycles S in a Calabi-Yau X. This is done using the machinery of A{sub {infinity}} products in the derived category of coherent sheaves of X, which in turn is related to the derived category of S and quiver path algebras. We confirm that the superpotential is what one might have guessed from analyzing the moduli space, i.e., it is linear in the fields corresponding to the Exts of the quiver and that each such Ext multiplies a polynomial in Exts equal to precisely the relation represented by the Ext.
A capstone course for a computer information systems major

This paper describes the current form and organization of Humboldt State University's CIS 492: Systems Design and Implementation, the capstone course for the Computer Information Systems (CIS) major. Since Spring 1998, this course has combined a team programming experience on a large-scale database project with discussions of a software engineering classic, Frederick Brooks Jr.'s “The Mythical Man Month”[1]. Students seem to find this combination valuable, and it is hoped that this paper can impart some useful ideas to others in designing a CIS/MIS capstone course.
Tracking the Sputnik Economy

In his 2011 State of the Union address, President Obama stressed investment in infrastructure, education and clean energy in the U.S. economy to "win the future." Edward Barbier of the University of Wyoming argues that to track the progress of such an investment strategy will require replacing GDP per capita as the main economic indicator with a Net Domestic Product (NDP) measure that is "adjusted" for real depreciation or appreciation in the reproducible, human and natural capital stock.
Automated pattern detection: an algorithm for constructing optimally synchronizing multi-regular language filters

In the computational-mechanics structural analysis of one-dimensional cellular automata the following automata-theoretic analogue of the change-point problem from time series analysis arises: Given a string σ and a collection {Di} offinite automata, identify the regions of σ that belong to each Di and, in particular, the boundaries separating them. We present two methods for solving this multi-regular language filtering problem. The first, although providing the ideal solution, requires a stack, has a worst-case compute time that grows quadratically in σ's length and conditions its output at any point on arbitrarily long windows of future input. The second method is to algorithmically construct a finite transducer that approximates the first algorithm. In contrast to the stack-based algorithm, however, the transducer requires only a finite amount of memory, runs in linear time, and gives immediate output for each letter read; it is, moreover, the best possible finite-state approximation with these three features.
Branes on the brane

Abstract We show that four-dimensional N=2 ungauged Einstein–Maxwell supergravity can be embedded on the Randall–Sundrum 3-brane, as a consistent Kaluza–Klein reduction of five-dimensional N=4 gauged supergravity. In particular, this allows us to describe four-dimensional Reissner–Nordstrom black holes within the Randall–Sundrum scenario. Using earlier results on the embedding of five-dimensional N=4 gauged supergravity in ten dimensions, we can then describe the four-dimensional Einstein–Maxwell supergravity on the 3-brane, and its solutions, from a type IIB viewpoint. We also show that the minimal ungauged supergravities in D=5 and D=6 can be consistently embedded in the half-maximally supersymmetric gauged supergravities in D=6 and D=7 , respectively. These allow us to construct solutions including BPS black holes and strings living in “Randall–Sundrum 4-branes”, and BPS self-dual strings living in “Randall–Sundrum 5-branes”. We can also lift the embeddings to ten-dimensional massive type IIA and D=11 supergravity respectively. In particular, we obtain a solution describing the self-dual string living in the world-volume of an M5-brane, which can be viewed as an open membrane ending on the M5-brane.
Comparison of Hydraulic Fracture Design Methods to Observed Field Results

The fracture models developed by Khristianovich and Zheltov, and Perkins, Kern, and Nordgren are compared to field, fracturing treatment data. It was found that the Khristianovich-Zheltov model agrees with the field data as adequately as the Perkins-Kern-Nordgren model, and that both models need to take changing instantaneous shut in pressure into account. A method for on-the-job fluid loss coefficient measurement is developed based on measurements of increasing instantaneous shut in pressure. Examples illustrating the fluid loss coefficient measurement method are discussed. Finally, examples are presented which show the excellent agreement between field data and production estimates based on Khristianovich- Zheltov fracture parameters. 24 references.
Nonlinear growth of singular-vector-based perturbations

The nonlinearity of singular-vector-based (SV-based) perturbation growth is examined within the context of a global atmospheric forecast model. The characteristics of these nonlinearities and their impact on the utility of SV-based diagnostics are assessed both qualitatively and quantitatively. Nonlinearities are quantified by examining the symmetry of evolving positive and negative ‘twin’ perturbations. Perturbations initially scaled to be consistent with estimates of analysis uncertainty become significantly nonlinear by 12 h. However, the relative magnitude of the nonlinearities is a strong function of scale and metric. Small scales become nonlinear very quickly while synoptic scales can remain significantly linear out to three days. Phase differences between the positive and negative perturbation patterns relative to each other can result in significant nonlinearities even when the basic anomaly patterns are quite similar. Thus, SVs may be qualitatively useful even when nonlinearities are large. Post-time forecast corrections using SV-based pseudo-inverse perturbations show that, despite significant nonlinear perturbation growth, the nonlinear forecast corrections are similar to the expected linear corrections, even at 72 h. When the nonlinear correction does differ significantly from the expected linear correction, the nonlinear correction is usually better, indicating that in some cases the pseudo-inverse correction effectively suppresses error growth outside the subspace defined by the leading (dry) SVs. Because a significant portion of the nonlinear growth occurs outside of the dry SV subspace, an a priori relative nonlinearity index based on the full perturbations is not a good predictor of when pseudo-inverse-based corrections will be ineffective. However, one can construct a reasonable predictor of pseudo-inverse ineffectiveness by considering the nonlinearities in the synoptic scales or in the SV subspace only. Copyright © 2003 Royal Meteorological Society
Toric ideals of lattice path matroids and polymatroids

Abstract White has conjectured that the toric ideal of a matroid is generated by quadric binomials corresponding to symmetric basis exchanges. We prove a stronger version of this conjecture for lattice path polymatroids by constructing a monomial order under which these sets of quadrics form Grobner bases. We then introduce a larger class of polymatroids for which an analogous theorem holds. Finally, we obtain the same result for lattice path matroids as a corollary.
Do rules of evidence apply (Only) in the courtroom? Deceptive interrogation in the United States and Germany

Scholars who compare common law and civil law countries have long argued that civil law legal systems like Germany do not employ formal rules of evidence comparable to those which govern American courtrooms. The complex and restrictive nature of American evidentiary rules is said to be an artifact of the adversarial process and lay juries, which the legal system does not trust to evaluate evidence dispassionately. Civil law systems that commit factfinding to mixed panels of lay and professional judges are said to have less need for formal rules of evidence that withhold information from decision-makers. My essay challenges this widely held view. Existing scholarship overlooks a rich source of evidentiary norms in the criminal process of civil law countries like Germany. Scholars have failed to recognize the dual ways in which evidentiary rules can function: they can restrict the presentation of evidence at trial; and they can shape its acquisition during pretrial investigation. German regulation of police interrogation—particularly its treatment of deceptive stratagems— provides a striking example of how investigative rules can limit and guide the acquisition of evidence. Germany forbids tricks and ruses common in American interrogations of the accused. Interrogation rules that prohibit the police from asking suspects leading questions or from assuming facts not in evidence greatly resemble the evidentiary principles that govern American trials. I will argue that German interrogation norms, like American evidentiary rules, shape the factual record on which the legal system assesses guilt or innocence—though unlike American evidentiary rules, interrogation norms are motivated not by distrust of the fact-finder but by the desire to protect criminal suspects from unfair manipulation. I will also show that American interrogation rules impose no comparable limits on investigative conduct. My essay examines both the institutional presuppositions and the implications of regulating the flow of evidence during acquisition in pretrial investigation rather than during presentation at trial. Filtering the flow of information at so early a stage in the criminal process benefits all criminal defendants, while American evidentiary rules matter to only that small minority of defendants who exercise their right to a trial (rather than negotiate a guilty plea.) Rules that regulate how police may ask questions shift responsibility for applying evidentiary rules from litigators to investigators. This presupposes a greater degree of investigative transparency along with a different system of pretrial discovery from that which governs the more adversarial pretrial process in common law countries. In the end, judicial skepticism about the possibility of constraining investigative practices may be one reason why the American criminal justice system filters evidence primarily at trial, where legal professionals pose questions publicly and under judicial supervision. 1 Professor of Law, University of Illinois College of Law.
Enhanced Dynkin diagrams and Weyl orbits

The root system Σ of a complex semisimple Lie algebra is uniquely determined by its basis (also called a simple root system). It is natural to ask whether all homomorphisms of root systems come from homomorphisms of their bases. Since the Dynkin diagram of Σ is, in general, not large enough to contain the diagrams of all subsystems of Σ, the answer to this question is negative. In this paper we introduce a canonical enlargement of a basis (called an enhanced basis) for which the stated question has a positive answer. We use the name an enhanced Dynkin diagram for a diagram representing an enhanced basis. These diagrams in combination with other new tools (mosets, core groups) allow us to obtain a transparent picture of the natural partial order between Weyl orbits of subsystems in Σ. In this paper we consider onlyADEroot systems (i.e., systems represented by simply laced Dynkin diagrams). The general case will be the subject of the next publication.
The Standard Model in its other phase

Abstract The Standard Model of particle physics is analyzed for the case of a Higgs potential not favoring spontaneous electroweak symmetry breaking to gain insight into the physics of the Standard Model. Electroweak breaking still takes place, and quarks and leptons still acquire masses but through bosonic technicolor. This “other” phase of the Standard Model exhibits interesting phenomena.
The microstructural, mechanical, and fracture properties of austenitic stainless steel alloyed with gallium

The mechanical and fracture properties of austenitic stainless steels (SSs) alloyed with gallium require assessment in order to determine the likelihood of premature storage-container failure following Ga uptake. AISI 304 L SS was cast with 1, 3, 6, 9, and 12 wt pct Ga. Increased Ga concentration promoted duplex microstructure formation with the ferritic phase having a nearly identical composition to the austenitic phase. Room-temperature tests indicated that small additions of Ga (less than 3 wt pct) were beneficial to the mechanical behavior of 304 L SS but that 12 wt pct Ga resulted in a 95 pct loss in ductility. Small additions of Ga are beneficial to the cracking resistance of stainless steel. Elastic-plastic fracture mechanics analysis indicated that 3 wt pct Ga alloys showed the greatest resistance to crack initiation and propagation as measured by fatigue crack growth rate, fracture toughness, and tearing modulus. The 12 wt pct Ga alloys were least resistant to crack initiation and propagation and these alloys primarily failed by transgranular cleavage. It is hypothesized that Ga metal embrittlement is partially responsible for increased embrittlement.
INTERACTION OF DISLOCATIONS WITH ELECTRONS AND WITH PHONONS

The interaction parameter of moving dislocations with electrons and with phonons was determined in aluminum, in the temperature range 10 to 250\ifmmode^\circ\else\textdegree\fi{}K. A new technique, involving a "dynamic bias stress", was developed for measuring ultrasonic-attenuation changes $\ensuremath{\Delta}\ensuremath{\alpha}$. The numerical values of the interaction parameter were obtained from the measured $\ensuremath{\Delta}\ensuremath{\alpha}$ by means of an analysis which does not require any knowledge of the dislocation density or of other inaccurately known features of the dislocation network. The results indicate that the dislocation interaction with electrons is temperature independent and the interaction with phonons increases with increasing temperature. These results are consistent with theoretical predictions.
Fractional-Order Complementary Filters for Small Unmanned Aerial System Navigation

Orientation estimation is very important for development of unmanned aerial systems (UASs), and is performed by combining data from several sources and sensors. Kalman filters are widely used for this task, however they typically assume linearity and Gaussian noise statistics. While these assumptions work well for high-quality, high-cost sensors, it does not work as well for low-cost, low-quality sensors. For low-cost sensors, complementary filters can be used since no assumptions are made with regards to linearity and noise statistics. In this article, the history and basics of complementary filters are included with examples, the concepts of filtering based on fractional-order calculus are applied to the complementary filter, and the efficacy of non-integer-order filtering on systems with non-Gaussian noise is explored with good success.
EXPERIMENTAL STUDIES OF INTENT INFORMATION ON COCKPIT TRAFFIC DISPLAYS

Intent information provides knowledge of another aircraft's current and future trajectory states. Prototype traffic displays were designed for four different levels of intent: No Intent, Rate, Commanded State, and Flight Management System (FMS)-Path. The TCAS Display was used as a baseline and represents the No Intent Level. The Rate, Commanded State, and FMS-Path Displays show increasing levels of intent information using TCAS-like symbology in addition to incorporating a conflict probe and profile view display. An experiment was run on the MIT Part Task Flight Simulator in which eight airline pilots flew five traffic scenarios with each of the four displays. Results show that pilots had fewer separation violations and maneuvered earlier with the three intent displays. Separation violations were reduced when pilots maneuvered earlier. A second experiment was run to compare performance between displaying intent information directly and incorporating it into a conflict probe. A different set of eight airline pilots flew four traffic scenarios with the TCAS and Commanded State Displays with and without the conflict probe. Conflict probes with two minute and long range look-ahead times were tested. Displaying conflict bands or showing intent information directly both led to fewer separation violations and earlier avoidance maneuvers than the base TCAS Display. Performance was similar between the two minute and long range look-ahead conflict probes. Pilots preferred all intent displays over the TCAS Display.
Applications of imaging radar data in Earth science investigations

Synthetic aperture radar (SAR) data provide unique information about the Earth's surface and biodiversity, including critical data for natural hazards and resource assessments. The ability to calculate the cross-section of a scatterer for any transmit and receive polarisation combination provides detailed information about vegetation for assessing changes in land cover, biomass and forest regrowth. Unique SAR interferometric measurements, predominantly large-scale surface change at fine resolution, are used to generate topographic data sets, monitor surface topographic change, and measure glacier ice velocity. The LightSAR mission, planned for launch in 2002 will be optimised for polarimetric and interferometric data acquisition in order to provide long-term observations of the Earth's changing conditions.
Aggregate Risk of Cardiovascular Disease Among Adolescents Perinatally Infected With the Human Immunodeficiency Virus

Background—Perinatally HIV-infected adolescents may be susceptible to aggregate atherosclerotic cardiovascular disease risk, as measured by the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) coronary arteries and abdominal aorta risk scores, as a result of prolonged exposure to HIV and antiretroviral therapy. Methods and Results—Coronary arteries and abdominal aorta PDAY scores were calculated for 165 perinatally HIV-infected adolescents, using a weighted combination of modifiable risk factors: dyslipidemia, cigarette smoking, hypertension, obesity, and hyperglycemia. Demographic and HIV-specific predictors of scores ≥1 were identified, and trends in scores over time were assessed. Forty-eight percent and 24% of the perinatally HIV-infected adolescents had coronary arteries and abdominal aorta scores ≥1, representing increased cardiovascular disease risk factor burden. Significant predictors of coronary arteries scores ≥1 included male sex, history of an AIDS-defining condition, longer du...
An Overview of Photovoltaic Power Systems

The United States is supporting a very aggressive research and development program in the field of photovoltaics. The goals of this program are to reduce the cost of solar cell arrays to a capital cost of 50¢/peak watt by the year 1986. The long-term goals are to achieve 10 to 30¢/peak watt by 1990 or 2000. The photovoltaic community is optimistic that the 1986 goals will be met with the use of silicon solar cells. The longer term goal may require the development of new thin film photovoltaic devices. As the price of solar cell arrays continues to decrease; the number of applications that are economically justified increases. The present production rates of photovoltaic arrays are close to 1 MW of production per year. The maximum expected efficiencies of 20 to 25 percent have already been achieved. Thus, cost reduction must come about through producing cells per unit area more cheaply. A separate alternative for producing low cost electricity from solar cells is to concentrate sunlight onto the cell, thus reducing the area of the cell per unit electrical output. Concentration systems also make available the option of using multiple cells to increase the overall conversion of sunlight to electricity. One two-cell concentration system has already demonstrated 28.5 percent efficiency.Copyright © 1979 by ASME
The Use of Spatial Cognitive Abilities in Geographical Information Systems: The Map Overlay Operation

Spatial cognitive abilities play an important role in the use of GIS, although they have yet to be examined in a controlled experimental setting. This study aimed to develop an experimental design which measures spatial cognitive abilities in the use of GIS, specifically the map overlay operation. Subjects (n = 134) received three map overlay tests in which they were given two of the following: input map layers, logical operator(s), or output map layer(s). Subjects were required to select the correct logical operator for Test 1, to select the correct output map layer for Test 2, and to select the correct input map layers for Test 3. Each test contained a total of 16 questions, based on a 4 (‘and’, ‘or’, ‘xor’, ‘not’ operators) × 2 (one or two polygons per map layer) × 2 (three or five polygon edges) factorial design. Results indicated a significant main effect of logical operators and number of polygons on performance; however, there was no effect of the number of polygon edges on performance. Significant two-way interactions revealed an effect of the number of polygon edges and the number of polygons using various logical operators on performance. In addition, performance was not significantly different between males and females or between GIS users and non-users. Overall, results show that map overlays in which a visual correspondence can be made between the same polygons in the input and output map layers are cognitively less demanding than map overlays in which the shape of the polygons have been radically transformed between the input and output map layers. This study helps further develop our understanding of the spatial cognitive abilities which are required in the use of GIS, and whether certain sub-populations differ in these cognitive abilities. These results may contribute to more effective and efficient GIS teaching and interface design by taking into account individual spatial cognitive abilities.
Diffraction in hadron-hadron interactions

Abstract Results on soft and hard diffraction in pp and p p collisions are reviewed with emphasis on factorization and scaling properties of differential cross sections. While conventional factorization breaks down at high energies, a scaling behavior emerges, which leads to a universal description of diffractive processes in terms of a (re)normalized rapidity gap probability distribution.
Racemic and diastereoselective synthesis of alkyl(1,3-butadien-2-yl)methanols via a novel homoallenylboration of aldehydes with diisopropyl 2,3-butadien-1-ylboronate

Abstract Diisopropyl 2,3-butadien-1-ylboronate has been prepared by a simple method and its utility as a novel homoallenylborating reagent has been demonstrated with a series of aldehydes. Also, a high diastereoselectivity of this reagent in its reaction with an α-chiral aldehyde has been established.
Baeyer−Villiger Oxidation Promoted by Reaction of Peracids with Cyclic Oxocarbenium Ions Generated in Situ from Internal Hemiketals

Reactive cyclic oxocarbenium ions, generated in situ from internal hemiketals, undergo Baeyer−Villiger oxidation upon exposure to m-chloroperbenzoic acid leading, after hydrolysis of the resultant lactones, to acyclic fragments for use in natural product synthesis.
Resolution of the long-standing overprediction of the resonance to intercombination line-intensity ratio in mid- Z neonlike ions

The Ne-like resonance 2p{sup 6} {sup 1}S-2p{sup 5}3d {sup 1}P (3C) to intercombination 2p{sup 6} {sup 1}S-2p{sup 5}3d {sup 3}D (3D) line-intensity ratio, R(3C/3D), has been extensively studied through high-accuracy measurements and calculations of atomic structure and collision cross sections. However, even state-of-the-art relativistic multiconfiguration atomic-physics codes generally predict values of R(3C/3D) that are significantly larger than those observed in coronal-density experiments. In this paper, predictions of R(3C/3D) across the Ne-like isoelectronic sequence from chromium to silver are brought into agreement with coronal-density experimental measurements in two steps: first by including a semiempirical correction in the collisional atomic data due to configuration-interaction effects, and next by including the effects of cascades on the upper level populations. The configuration-interaction correction is inspired by the observation that nearly all data-production codes fail to predict R(3C/3D) correctly and is justified theoretically by a careful analysis of configuration-interaction contributions to level energies. The dependence of R(3C/3D) with electron density and its agreement with moderate-density measurements are shown. A brief description of the application of our technique to line ratios in He- and Ni-like x-ray spectra is also given.
Synchrony and Periodicity in Excitable Neural Networks with Multiple Subpopulations

We consider a cascading model of excitable neural dynamics and show that over a wide variety of parameter regimes, these systems admit unique attractors. For large coupling strengths, this attractor is a limit cycle, and for small coupling strengths, it is a fixed point. We also show that the cascading model considered here is a mean-field limit of an existing stochastic model.
Spectroscopic Confirmation of the Cl 1604 Supercluster at z ~ 0.9

We present spectroscopic confirmation of the Cl 1604 supercluster at z ~ 0.9. The supercluster was originally detected as two individual clusters, Cl 1604+4304 at z = 0.90 and Cl 1604+4321 at z = 0.92, which are closely separated in both redshift and sky position. Subsequent imaging revealed a complex of red galaxies bridging the two clusters, suggesting that the region contained a large-scale structure. We have carried out extensive multiobject spectroscopy, which, combined with previous measurements, provides ~600 redshifts in this area, including 230 confirmed supercluster members. We detect two additional clusters that are part of this structure, Cl 1604+4314 at z = 0.87 and Cl 1604+4316 at z = 0.94. All four have properties typical of local clusters, with line-of-sight velocity dispersions between 489 and 962 km s-1. The structure is significantly extended in redshift space, which, if interpreted as a true elongation in real space, implies a depth of 93 h Mpc. We examine the spatial and redshift distribution of the supercluster members.