cssi/SciSciGPT-SciSciNet huggingface dataset:
Estimating crustal seismic anisotropy with a joint analysis of radial and transverse receiver function data

SUMMARY We developed an integrated technique for estimating crustal anisotropy with a horizontal axis using radial (R) and transverse (T) receiver functions. The technique includes computing three individual and one joint objective function (JOF) and a reliability analysis of the estimated anisotropy. The individual objective functions (IOFs) are designed to: (1) maximize the peak energy of the stacked R receiver function after a cosine moveout correction in the Ps arrival time; (2) to maximize the correlation of the radial receiver functions after a full correction of anisotropy or (3) to minimize the total energy of transverse receiver functions stacked after a removal of crustal anisotropy. The JOF was computed by a weighted average of the three IOFs, and the reliability analysis uses the principle that stacking coherent signals can lead to an increase of signal-to-noise ratio. We applied the technique to synthetic receiver functions generated with 30–60 per cent white noise from a variety of anisotropic and heterogeneous models. The synthetic tests indicate that the proposed technique has good capability to recover the input models. Despite the presence of random and other coherent noises, such as those caused by inhomogeneous structures, in the data, the technique can always provide accurate estimates of crustal anisotropy. We applied the technique to two permanent seismic stations in western China and found significant crustal anisotropy beneath one station located at the northern edge of the Tibetan plateau. The observed fast polarization direction at this station follows the direction of the maximum horizontal tensile stress, suggesting that the observed seismic anisotropy is likely caused by mineral alignment in the lower crust. The station situated in the Sichuan basin, on the other hand, shows little to no seismic anisotropy, which may suggest that the crust beneath the basin is nearly rigid with very little deformation. The developed technique can be applied to any broadband seismic stations that have a good backazimuthal coverage of teleseismic events.
Shareholders' Wealth-Maximizing Operating Decisions and Risk Management Practices in a Mixed Contracts Economy

This paper establishes a critically important positive role for operations management practices and financial hedging. We show that operations management decisions and financial hedging are intertwined, and we advance a framework that can identify their combined effects on investors' wealth. We show that: (a) firms (publicly traded corporations) will optimally hold adequate riskless working capital (e.g., cash) to minimize the cost of obtaining non-financial inputs, and the magnitude of this cash holding depends on operating details, and (b) operations management and financial hedging can lower firms' cash requirements, and boost productivity, defined as the wealth created in the firm per dollar of invested capital. Productivity-enhancing practices—by “freeing up” some of the firm's cash—can maximize the investors' wealth. We show that these results obtain because firms' contracts with many of the providers of non-financial inputs are not traded, and because investors can invest not just in public corporations but also in businesses “outside the markets” (e.g., proprietorships, partnerships, and private equity).
Height bounds on zeros of quadratic forms over \overline{\mathbb Q}

In this paper, we establish three results on small-height zeros of quadratic polynomials over \(\overline{\mathbb Q}\). For a single quadratic form in \(N \ge 2\) variables on a subspace of \(\overline{\mathbb Q}^N\), we prove an upper bound on the height of a smallest nontrivial zero outside of an algebraic set under the assumption that such a zero exists. For a system of k quadratic forms on an L-dimensional subspace of \(\overline{\mathbb Q}^N\), \(N \ge L \ge \frac{k(k+1)}{2}+1\), we prove existence of a nontrivial simultaneous small-height zero. For a system of one or two inhomogeneous quadratic and m linear polynomials in \(N \ge m+4\) variables, we obtain upper bounds on the height of a smallest simultaneous zero, if such a zero exists. Our investigation extends previous results on small zeros of quadratic forms, including Cassels’ theorem and its various generalizations and contributes to the literature of so-called “absolute” Diophantine results with respect to height. All bounds on height are explicit.
High-frequency and -field electron paramagnetic resonance of vanadium(IV, III, and II) complexes

Abstract In this review, we discuss the advantages of performing electron paramagnetic resonance (EPR) on coordination and metalloorganic complexes containing various oxidation states of vanadium, from +4 to +2, using the high-frequency and -field version of this technique, known as HFEPR. Thus, HFEPR is advantageous in investigating ( S = 1/2) V(IV) species due to its higher g -factor resolution over conventional EPR, albeit at the price of losing the hyperfine structure resolution due to g -strain. It is very much desirable in characterizing ( S = 3/2) V(II) complexes since it is capable of precisely and accurately measuring the zero-field splitting present in these species. Finally, HFEPR is indispensable in investigating ( S = 1) V(III) species, which in conventional conditions are often “EPR-silent” due to the combination of their large zero-field splitting and integer spin number. The use of HFEPR thus can provide additional information regarding the oxidation state of the metal and the coordination geometry.
Incompressible Limit for the Compressible Flow of Liquid Crystals

The connection between the compressible flow of liquid crystals with low Mach number and the incompressible flow of liquid crystals is studied in a bounded domain. In particular, the convergence of weak solutions of the compressible flow of liquid crystals to the weak solutions of the incompressible flow of liquid crystals is proved when the Mach number approaches zero; that is, the incompressible limit is justified for weak solutions in a bounded domain.
Indole-derived arynes and their Diels-Alder reactivity with furans.

Arynes derived from any position of the ubiquitous indole nucleus are unknown. We have now provided the first evidence for the formation and trapping of the 4,5-, 5,6-, and 6,7-indolynes. A series of o-dihalo indoles (Cl, Br, F) were synthesized and reacted under metal-halogen exchange conditions to give Diels−Alder cycloadducts in high yield with furan. The use of an excess of tert-butyllithium resulted in the rearrangement of the initially formed cycloadduct; however, employing only a slight excess of n-butyllithium cleanly gave cycloadducts with furan.
Isoperimetry of waists and local versus global asymptotic convex geometries

Existence of nicely bounded sections of two symmetric convex bodies K and L implies that the intersection of random rotations of K and L is nicely bounded. For L = subspace, this main result immediately yields the unexpected phenomenon: "If K has one nicely bounded section, then most sections of K are nicely bounded". This 'existence implies randomness' consequence was proved independently in [Giannopoulos, Milman and Tsolomitis]. The main result represents a new connection between the local asymptotic convex geometry (study of sections of convex bodies) and the global asymptotic convex geometry (study of convex bodies as a whole). The method relies on the new 'isoperimetry of waists' on the sphere due to Gromov.
The Discovery of a P Cygni Analog in M31

We present spectroscopy and discuss the photometric history of a previously obscure star in M31. The spectrum of the star is an extremely close match to that of P Cygni, one of the archetypes of luminous blue variables (LBVs). The star has not shown much variability over the past 40 years (<0.2 mag), although small-scale (0.05 mag) variations over a year appear to be real. Nevertheless, the presence of a subarcsecond extension around the star is indicative of a past outburst, and from the nebula's size (0.5 pc diameter) we estimate that the outburst took place roughly 2000 years ago. P Cygni itself exhibits a similar photometric behavior and has a similar nebula (0.2 pc diameter). We argue that this may be more typical behavior for LBVs than commonly assumed. The star's location in the H-R diagram offers substantial support for stellar evolutionary models that include the effects of rotation, as the star is just at a juncture in the evolutionary track of a 85 M☉ star. The star is likely in a transition from an O star to a late-type WN Wolf-Rayet star.
Monetary incentives versus class credit: Evidence from a large classroom trust experiment

This paper reports an experimental investigation of a trust game using either cash or class credit as incentives to participants. We recruit from two auditorium classes. In one class, each token has cash value; in the other, each token is worth extra-credit points added to the students’ overall average at the end of the semester. The results indicate that using extra-credit points to motivate participants generates qualitatively similar data on average as participants incentivized with cash. We do find a difference in behavior with second movers who expect a low grade, but those incentivized with class credit are closer to the game theoretic prediction.
Temporal Changes in Streptococcal M Protein Types and the Near-Disappearance of Acute Rheumatic Fever in the United States

BACKGROUND The explanation for the very substantial decrease in the incidence of acute rheumatic fever in the United States, particularly over the past 50 years, is unclear. It has been proposed that certain M types of group A streptococci (GAS) include strains that are particularly rheumatogenic and that others are nonrheumatogenic. METHODS We compared the M type distribution of GAS recovered from children from Chicago, Illinois, with acute pharyngitis during 1961-1968 to that of GAS recovered from Chicago children and children from across the United States in 2000-2004, with attention to changes in M types that previously were associated with rheumatogenic strains. RESULTS The rheumatogenic types 3, 5, 6, 14, 18, 19, and 29 comprised 49.7% of 468 pharyngeal isolates during 1961-1968 but only 10.6% of 450 Chicago isolates during 2000-2004 (P < .001) and 17.9% of 3969 isolates nationwide during 2000-2004 (P < .001). Significant decreases in types 3, 5, and 6 and virtual disappearance of types 14, 18, 19, and 29 occurred between the 2 study periods. No change in the proportion of type 1 isolates, a highly heterogeneous group that includes some rheumatogenic strains, was observed. The nonrheumatogenic GAS types 2, 4, 22, and 28 increased from 4.9% to approximately 28% of pharyngeal isolates in Chicago and nationwide between the 2 study periods (P < .001). CONCLUSIONS These data support the concept of rheumatogenic strains of GAS and indicate that the marked decrease in the incidence of acute rheumatic fever in the United States over the past 4 decades is correlated with the replacement of rheumatogenic types by nonrheumatogenic types in cases of acute streptococcal pharyngitis in children. The reasons underlying the observed change in distribution of M types remain to be elucidated.
On Breaking Cosmic Degeneracy

It has been argued that the power spectrum of the anisotropies in the cosmic microwave background may be effectively degenerate, namely, that the observable spectrum does not determine a unique set of cosmological parameters. We describe the physical origin of this degeneracy and show that at small angular scales it is broken by gravitational lensing: effectively degenerate spectra become distinguishable at l~3000 because lensing causes their damping tails to fall at different rates with increasing l. This effect also helps in distinguishing nearly degenerate power spectra such as those of mixed dark matter models. Forthcoming interferometer experiments should provide the means of measuring otherwise degenerate parameters at the 5%-25% level.
Surgical palliative care: recent trends and developments.

A 55-year-old woman with a history of stage III ovarian carcinoma, 1 year after totalabdominal hysterectomy, bilateral salpingo-oophorectomy and omentectomy, andseveral cycles of cisplatin-based chemotherapy, presents at a 350-bed regionalmedical center with increasing abdominal pain and distention, nausea, and vomiting.Shewastoldshewasstableatherlastoutpatientoncologyevaluation2monthsprevi-ously when she was complaining of abdominal pain, numbness in her feet, and loss ofappetite. She is receiving no regular medications except propoxyphene with acet-aminophen (Darvocet) as needed for abdominal pain. On physical examination sheis pale and cachectic. She has diminished breath sounds with dullness to percussionat each lung base, more so on the right. Her abdomen is distended with a remotemidline incision.Bowelsoundsarehighpitched.Shehasshiftingdullnesstopercussionandmultiplepalpable abdominal masses. She has no guarding. Plain abdominal radiographs areconsistent with a small-bowel obstruction. Bilateral moderate-sized pleural effusionsare noted on the chest radiograph. The surgeon tells her he thinks she has a bowelobstruction from her cancer and he would like to avoid operating if at all possible.A nasogastric (NG) tube is inserted and placed to continuous suction. She is not givenopioid analgesia because of the surgeon’s fear of masking peritoneal signs. After5 days of nonoperative therapy the patient is advised that her condition mandatessurgery because of persistent obstruction and fears of potential gangrenous bowel.She signs an operative consent for exploratory laparotomy, possible bowel resection,removal of tumor, possible formation of ostomy, and insertion of central venous cath-eter. Potential complications listed include failure to remove the entire tumor,
Government regulation of forestry practices on private forest land in the United States: An assessment of state government responsibilities and program performance

Abstract In 2003, a comprehensive assessment of state government, forest practice regulatory programs in the United States was undertaken. Involved was an extensive review of the literature and information gathering from program administrators in all 50 states. The assessment determined that regulatory programs focus on a wide range of forestry practices applied to private forests; state agencies regulating forestry practices are numerous and responsible for substantial investment in forest practice regulatory programs; 15 state governments have especially prominent regulatory programs; and past evaluations of regulatory program performance have produced mixed results. Program administrators suggest regulatory program design and administration would benefit from research focused on identifying forestry sectors requiring regulatory attention; design of regulatory programs and means for evaluating their performance; equity and distributional consequences of regulatory program enforcement; and the design of information management systems for monitoring regulatory programs.
Clinical estimation of fundamental frequency: The 3m plastiform magnetic tape viewer

Abstract A procedure and method is described to determine the frequency or pitch of tape-recorded voice samples, while keeping the cost of measurement within the reach of practicing clinicians. The method described reduces the uncertainty of pitch determination by comparison techniques and improves the accuracy of clinical estimation of fundamental vocal frequency and pitch. The accuracy, reliability, cost, and ease with which the method can be used makes it a viable tool to be used by the clinician.
Calculation of the dose in the build-up region for high energy photon beam. Treatment planning when beam spoilers are employed

Recoil electrons from a polystyrene sheet (beam spoiler) placed in a photon beam were used to modulate the dose in the build-up region. The effects of the beam spoiler on the dosimetry in simple phantoms were studied for both 6 MV and 15 MV photon beams at 100 cm source-to-surface distance (SSD) as a function of (1) the thickness of the spoiler, (2) the spoiler-to-surface distance (SD) and (3) the field size. A radiotherapy treatment planning (RTP) algorithm was used that employs pencil beam dose deposition kernels to evaluate the three-dimensional (3D) dose distribution due to photons and electrons in the build-up region. To determine the energy deposition kernels for the recoil electrons emanating from the spoiler, their energy spectrum needs to be known. Monte Carlo simulations were performed to derive the spectrum of electrons from the beam spoiler. The recoil electron spectrum was found to be nearly independent of field size, SD, and spoiler thickness. The pencil beam energy deposition kernel was calculated for the recoil electrons from the spoiler and inserted in the treatment planning algorithm. The dose calculation algorithm permits merging the photon and recoil electron dose components. In all cases the calculation agrees to within 3% of the measured results.
Calculation of Transonic Flow over Supercritical Airfoil Sections

Two numerical methods for calculating the transonic flow, including viscous effects over lifting airfoil sections and experimental data are compared for turbulent flow over a supercritical airfoil. In addition, results for a NACA 64A010 airfoil at nonzero angle of attack are compared to demonstrate the applicability of the numerical methods to classical, lifting airfoils. One numerical method is a solution to the time-averaged Navier-Stokes equations throughout the entire flow field. The other is a hybrid method that combines inviscid, boundary-layer, and Navier-Stokes equations in appropriate regions of the flow field. Both methods adequately predict the surface pressures and flow field about the 64A010 airfoil at M = 0.8 and alpha = 2 deg when an appropriate turbulence model is used. The methods are not as successful for the supercritical airfoil.
Spectroscopy of fermionic operators in AdS/CFT

We compute the spectrum of color-singlet fermionic operators in the = 2 gauge theory on intersecting D3 and D7-branes using the AdS/CFT correspondence. The operator spectrum is found analytically by solving the equations for the dual D7-brane fluctuations. For the fermionic part of the D7-brane action, we use the Dirac-like form found by Martucci et al. ([26]). We also consider the baryon spectrum of a large class of supersymmetric gauge theories using a phenomenological approach to the gauge/gravity duality.
Quasi-thermodynamic prediction of hydrogen reemission behavior from titanium films

Abstract A new approach is developed to describe hydrogen reemission behavior from a reactive metal film in which the implanted hydrogen concentration exceeds the dilute solution range. In this approach, conventional thermodynamic information for the metal-hydrogen system, namely, the phase diagram and the P-C-T (pressure-concentration-temperature) relation is used extensively to determine the reemitted hydrogen flux. As a specific case, this method has been applied to hydrogen reemission from a titanium film. The predicted reemission curves show characteristic discontinuities in time corresponding to phase changes in the solid titanium-hydrogen system as the system proceeds to a final stationary state. Such discontinuities have been found in existing experimental data on deuterium reemission from titanium oxide and carbide coatings but were neglected as being exceptional. The corresponding hydrogen concentration build-up in the titanium film does smoothly approach the stationary state value. The effects of temperature (300–800 K), titanium film thickness (10–3000 A), and incoming hydrogen flux ( 1.0 × 10 16 to 1.0 × 10 18 H atoms/cm 2 .s) on the hydrogen reemission behavior are investigated. The time required to reach a stationary state changes reasonably with incoming hydrogen flux and film thickness. This characteristic transient time minimizes at ~ 600 K and maximizes at ~ 700 K. The stationary state hydrogen concentration is found to be independent of film thickness. An F-C-T (flux-concentration-temperature) relation is derived and used to estimate the stationary state hydrogen concentration for a given flux and temperature.
Estimation and equalization of fading channels with random coefficients

Abstract The time-varying tap coefficients of frequency-selective fading channels are typically modeled as random processes with low-pass power spectra. However, traditional adaptive techniques usually make no assumption on the channel's time variations and hence do not exploit this information. In this paper, Kalman filtering methods are derived to track the channel by employing a multichannel autoregressive description of the time-varying taps in a decision-feedback equalization framework. Fitting a model to the variations of the channel's taps is a challenging task because the tap coefficients are not observed directly. Higher-order statistics are employed in this paper in order to estimate the model parameters from input/output data. Consistency of the proposed method is shown, and some illustrative simulations are presented.
Effects of leading-edge roughness on fluid flow and heat transfer in the transitional boundary layer over a flat plate

Abstract An experimental study was undertaken to gain insight into the physical mechanisms that affect the laminar-turbulent transition process downstream of the leading-edge roughness condition. Sandpaper strips and small cylinders were attached to the leading edge of a heated test surface to simulate leading edge roughness typical of gas turbine blades. The roughness Reynolds numbers ranged from 2 to 2840. For free-stream velocities less than 5 m s −1 , the maximum roughness height was the primary contributor to deviations from the undisturbed case, irrespective of the roughness geometry. At higher free-stream velocities (5–7 m s −1 ), three of the rough leading-edge conditions induced a dual-slope region between the laminar and turbulent Stanton number correlations. Boundary layer measurements indicated that the first segment of the dual-slope was laminar, but the wall heat transfer significantly deviates from the laminar correlation. The second segment was transitional. The dual-slope behaviour and a waviness in the Stanton number distribution observed at higher free-stream velocities are believed to have been caused by nonlinear amplification caused by the finite disturbances at the leading edge.
All-optical delay of images using slow light

Two-dimensional images are delayed in a cesium vapor cell. The transverse phase and amplitude profiles of the images are shown to be preserved, even at very low light levels.
Robust Statistics, Hypothesis Testing, and Confidence Intervals for Persistent Homology on Metric Measure Spaces

We study distributions of persistent homology barcodes associated to taking subsamples of a fixed size from metric measure spaces. We show that such distributions provide robust invariants of metric measure spaces and illustrate their use in hypothesis testing and providing confidence intervals for topological data analysis.
Transport of Photoelectrons in the Nightside Magnetosphere

Kinetic modeling results are analyzed to examine the transport of photoelectrons through the nightside inner magnetosphere. Two sources are considered, those on the dayside from direct solar illumination and those across the nightside from light scattered by the upper atmosphere and geocorona. A natural filter exists on the nightside for the dayside photoelectrons. Coulomb collisions erode the distribution at low energies and low L shells, and magnetospheric convection compresses the electrons as they drift toward dawn. It is shown that for low-activity levels a band of photoelectrons forms between L = 4 and 6 that extends throughout the nightside local times and into the morning sector. For the scattered light photoelectrons the trapped zone throughout the nightside is populated with electrons of E less than 30 eV. At high L shells near dawn, convective compression on the nightside yields an accelerated population with electrons at energies up to twice the ionospheric energy maximum (that is, roughly 1200 eV for dayside photoelectrons and 60 eV for scattered light electrons). Modeled energy and pitch angle distributions are presented to show the features of these populations.
A comparison between coherent and spontaneous Raman scattering for biological imaging

We compare imaging using coherent and spontaneous Raman scattering under biological imaging conditions. We perform spectral domain imaging of polystyrene beads and find comparable signal levels for both methods at excitation powers and concentrations most relevant for biological samples. The critical power at which the two methods provide equivalent signal levels is found to be ∼1.3 mW in 10 M polystyrene beads and ∼7 mW in 13 M 2-propanol. The low sample concentrations and low excitation power necessary for most biological imaging applications reduce the relative advantages offered by coherent Raman methods.
Separation of bulk and surface-losses in low-loss EELS measurements in STEM

Abstract To identify major features in low electron energy loss spectra, the different excitations (bulk plasmons, interband transitions, surface plasmons, Cherenkov and surface guided modes) must be delineated from each other. In this paper, this process is achieved by noting the linear thickness dependence of bulk processes contrasted with the constant thickness behavior of surface excitations. An alternative approach of analyzing bulk plasmon-loss is also introduced. Using a new algorithm, the parameters of plasma generation—plasmon energy E P , 0 , a damping parameter Δ E P and the coefficient of the dispersion relation γ were obtained from a single curve fitting on the example of Si. The ability to separate surface-losses from the rest of the data permitted identification of the fine structure of the surface-losses. The strong peak at 8.2 eV characteristic of non-radiative surface plasmon excitations was measured for Si. Analysis of surface excitations indicates that a 10 A SiO 2 surface coating layer is still present despite careful cleaning the specimen. Dielectric functions deduced from the EELS data prove to be considerably affected by the presence of the surface-losses for samples as thick as 800 A .
Pd-Catalyzed Intermolecular Amidation of Aryl Halides: The Discovery that Xantphos Can Be Trans-Chelating in a Palladium Complex

A general method for the intermolecular coupling of aryl halides and amides using a Xantphos/Pd catalyst is described. This system displays good functional group compatibility, and the desired C−N bond forming process proceeds in good to excellent yields with 1−4 mol % of the Pd catalyst. Additionally, the arylation of sulfonamides, oxazolidinones, and ureas is reported. The efficiency of these transformations was found to be highly dependent on reaction concentrations and catalyst loadings. A Pd complex resulting from oxidative addition of 4-bromobenzonitrile, (Xantphos)Pd(4-cyanophenyl)(Br) (II), was prepared in one step from Xantphos, Pd2(dba)3, and the aryl bromide. Complex II proved to be an active catalyst for the coupling between 4-bromobenzonitrile and benzamide. X-ray crystallographic analysis of II revealed a rare trans-chelating bisphosphine-Pd(II) structure with a large bite angle of 150.7°.
Supersymmetric biorthogonal quantum systems

We discuss supersymmetric biorthogonal systems, with emphasis given to the periodic solutions that occur at spectral singularities of PT symmetric models. For these periodic solutions, the dual functions are associated polynomials that obey inhomogeneous equations. We construct in detail some explicit examples for the supersymmetric pairs of potentials V±(z)=−U(z)2±z(d∕dz)U(z) where U(z)≡∑k>0υkzk. In particular, we consider the cases generated by U(z)=z and z∕(1−z). We also briefly consider the effects of magnetic vector potentials on the partition functions of these systems.
Conversational text input for modifying graphics facial images

This paper reports on a text interpretation program for a minicomputer with 8K memory to facilitate modifying line drawings of faces. An interactive language is described that allows conversational dialogues between the user and image modification routines. We present an implementation that retains context during a dialogue and makes possible relational adjustments of facial features. Imprecise feature judgements issued by the user are used to modify images. Ambiguities encountered by the program are resolved by interrogating short term memory buffers and hash table data. Language and hardware features are combined by data structures that interface display processor instructions and requests generated by the interpreted text. The updating of these structures is discussed in terms of relationships between structure elements.
A source reconstruction process based on an indirect variational boundary element formulation

The objective of the work presented in this paper is the development of a computational capability for recreating the vibration of a source from acoustic field data. The formulation is based on the indirect variational boundary element method (IVBEM). The vibration of the source is computed from transfer functions defined between the field points, where the acoustic pressure of the original field is prescribed, and the surface of the source. The IVBEM is employed for deriving the transfer functions. The capability to account for the presence of obstacles in the field adjacent to the vibrating sources is included in the source reconstruction process. Treatment of irregular frequencies is included in the IVBEM formulation employed in this work and the reconstruction of the source can be achieved for all radiation conditions. A singular value decomposition (SVD) solver is integrated with the IVBEM computations in order to evaluate the vibration of the source from the transfer functions and the acoustic field data. An algorithm that identifies the optimum field points where the acoustic pressure of the original field must be prescribed in order to accomplish the most efficient source reconstruction is also developed. The optimum field points are selected from a set of prescribed candidate points. The selection of the optimum points is based on the geometric characteristics of the source, the frequency of analysis, the locations of the candidate points, and the properties of the medium. There is no need to have information about the acoustic field in order to identify the optimum field points. Several validation and application cases are presented.
Inequivalent embeddings of SU(2) and instanton interactions

Abstract The fact that SU(2) allows inequivalent embeddings inside larger groups is shown to have some consequences for the interaction of instantons.
DIPYRRYL KETONES FROM DIPYRRYLMETHANES

Dipyrrylmethanes are smoothly and efficiently oxidized to dipyrryl ketones by ceric ammonium nitrate in water-tetrahydrofuran-acetic acid solvent at room temperature.
Coordinated load balancing, handoff/cell-site selection, and scheduling in multi-cell packet data systems

We investigate a wireless system of multiple cells, each having a downlink shared channel in support of high-speed packet data services. In practice, such a system consists of hierarchically organized entities including a central server, Base Stations (BSs), and Mobile Stations (MSs). Our goal is to improve global resource utilization and reduce regional congestion given asymmetric arrivals and departures of mobile users, a goal requiring load balancing among multiple cells. For this purpose, we propose a scalable cross-layer framework to coordinate packet-level scheduling, call-level cell-site selection and handoff, and system-level cell coverage based on load, throughput, and channel measurements. In this framework, an opportunistic scheduling algorithm--the weighted Alpha-Rule--exploits the gain of multiuser diversity in each cell independently, trading aggregate (mean) down-link throughput for fairness and minimum rate guarantees among MSs. Each MS adapts to its channel dynamics and the load fluctuations in neighboring cells, in accordance with MSs' mobility or their arrival and departure, by initiating load-aware handoff and cell-site selection. The central server adjusts schedulers of all cells to coordinate their coverage by prompting cell breathing or distributed MS handoffs. Across the whole system, BSs and MSs constantly monitor their load, throughput, or channel quality in order to facilitate the overall system coordination. Our specific contributions in such a framework are highlighted by the minimum-rate guaranteed weighted Alpha-Rule scheduling, the load-aware MS handoff/cell-site selection, and the Media Access Control (MAC)-layer cell breathing. Our evaluations show that the proposed framework can improve global resource utilization and load balancing, resulting in a smaller blocking rate of MS arrivals without extra resources while the aggregate throughput remains roughly the same or improved at the hot-spots. Our simulation tests also show that the coordinated system is robust to dynamic load fluctuations and is scalable to both the system dimension and the size of MS population.
Grid diagrams and shellability

We explore a somewhat unexpected connection between knot Floer homology and shellable posets, via grid diagrams. Given a grid presentation of a knot K inside S^3, we define a poset which has an associated chain complex whose homology is the knot Floer homology of K. We then prove that the closed intervals of this poset are shellable. This allows us to combinatorially associate a PL flow category to a grid diagram.
CdTe Films Grown on InSb Substrates by Organometallic Epitaxy

Cadmium telluride layers were grown on InSb substrates by organometallic vapor phase epitaxy and examined using secondary ion mass spectrometry (SIMS), photoluminescence (Pb) and double crystal x-ray diffraction (DCD). The substrate temperature and the nature of the surface prior to growth are shown to be the most important parameters which influence the quality of CdTe layers. Growth on diethyltelluride (DETe) stabilized InSb substrates resulted in CdTe growth with a misorientation of about 4 minutes of arc with respect to the substrates. On the other hand, the grown layers followed the orientation of the substrates when a dimethylcadmium (DMCd) stabilized InSb was used. Growth at 350°C resulted in the smallest x-ray rocking curve (DCRC) full width at half maximum (FWHM) of about 20 arc seconds.
An Analytical Investigation of Short-Period Flying Qualities

Longitudinal short-period flying qualities boundaries are defined in terms of parameters of the closed-loop pilot-airplane system. The parameters are varied to match analytical boundaries to several experimental "good" flying qualities boundaries. Parameter values which provide matching are compared to values assumed good in previous analyses of a similar nature. The analytical and experimental boundaries agree well and provide a means for experimentally determining good parameter values. It is concluded that there is an upper bound on short-period frequency for good flying qualities and that pilots accept lower values of closed-loop damping ratio than those previously assumed to be acceptable. Nomenclature AQ = numerator polynomial coefficient in pitch-elevato r transfer function g — acceleration due to gravity Gc = controlled element transfer function Gp = pilot linear transfer function i = imaginary unit ,(—!)* Kp = pilot gain Lx = variation of lift, Z,, with angle of attack, a MI = variation of pitching moment, M, with input or motion quantity, / q = pitching velocity s = Laplace transform variable T02 = pitch angle-elevator transfer function numerator time constant x, y = Cartesian coordinates in the complex plane, z = x -f iy Zw = variation of Z-direction force with vertical velocity, w a = angle of attack Se = elevator deflection £CL = closed-loop damping ratio /C,sp = damping ratio of short-period oscillation £, 7] = pole/zero cartesian coordinates in the complex plane, z=£ + iri 6 — pitch angle Ot = contribution of the /th pole or zero to argument of the rootlocus r = pilot pure time delay constant CL = closed-loop, undamped natural frequency coSp = undamped natural frequency of short-period oscillation
Neuromuscular effects of mivacurium in 2- to 12-yr-old children with burn injury.

Background: Burned patients are usually resistant to the neuromuscular effects of nondepolarizing relaxants, mostly because of receptor changes. The magnitude of the resistance is related to burn size and time after burn. Mivacurium is a muscle relaxant, degraded by plasma cholinesterase, whose enzyme activity is decreased in burns. The present study tested the hypothesis that burn-induced depressed plasma cholinesterase activity counteracts the receptor-mediated resistance, resulting in a lack of resistance to mivacurium. Methods: Burned patients (n = 23), aged 2-12 yr, subclassified into burns of 10-30% or > 30% of body surface, were studied at ≤ 6 days and again at 1-12 weeks after burn if possible. Thirteen additional patients served as controls. Neuromuscular variables monitored included onset and recovery following bolus dose, continuous infusion rates required to maintain 95 ± 4% paralysis, and recovery rates following infusion. Results: The onset times of maximal twitch suppression were not different between burns and controls, but recovery to 25% of baseline twitch height was prolonged in patients with > 30% burn irrespective of time after injury. The continuous infusion rates to maintain twitch suppression at 95 ± 4% were not different between groups. The recovery indices, including train-of-four to > 75%, 25-75%, or 5-95% in burned patients, were similar or prolonged compared with controls. The prolonged recovery in burned patients was inversely related to plasma cholinesterase activity (R 2 = 0.86, r = - 0.93, P < 0.001), and the decreased plasma cholinesterase activity was related to burn size and time after burn. Conclusions: A normal mivacurium dosage (0.2 mg/kg) effects good relaxation conditions in burned patients, with an onset time similar to that in controls. This finding contrasts with the response seen with other nondepolarizing drugs, higher doses of which are required to effect paralysis. The decreased metabolism of mivacurium, resulting from depressed plasma cholinesterase activity, probably counteracts the receptor-mediated potential for resistance. Because succinylcholine is contraindicated in burned patients, larger doses of nondepolarizing agents are advocated to effect rapid onset of paralysis. This generalization does not hold for mivacurium.
Measurements of Rotordynamic Coefficients of Hybrid Bearings With (a) a Plugged Orifice, and (b) a Worn Land Surface

Test results are presented for the rotordynamic coefficients of a hybrid bearing that is representative of bearings for liquid-rocket-engine turbopump applications. The bearing is tested in the following two degraded conditions: (a) one of five orifices plugged, and (b) a locally enlarged clearance to simulate a worn condition. Test data are presented at 24,600 rpm, with supply pressures of 4.0, 5.5, and 7.0 MPa, and eccentricity ratios from 0.1 to 0.5 in 0.1 increments. Overall, the results suggest that neither a single plugged orifice nor significant wear on the bearing land will disable a well-designed hybrid bearing. These results do not speak to multiple plugged orifices and are not an endorsement for operations without filters to prevent plugging orifices.
Combinatorial Lie bialgebras of curves on surfaces

Abstract Goldman (Invent. Math. 85(2) (1986) 263) and Turaev (Ann. Sci. Ecole Norm. Sup. (4) 24 (6) (1991) 635) found a Lie bialgebra structure on the vector space generated by non-trivial free homotopy classes of curves on a surface. When the surface has non-empty boundary, this vector space has a basis of cyclic reduced words in the generators of the fundamental group and their inverses. We give a combinatorial algorithm to compute this Lie bialgebra on this vector space of cyclic words. Using this presentation, we prove a variant of Goldman's result relating the bracket to disjointness of curve representatives when one of the classes is simple. We exhibit some examples we found by programming the algorithm which answer negatively Turaev's question about the characterization of simple curves in terms of the cobracket. Further computations suggest an alternative characterization of simple curves in terms of the bracket of a curve and its inverse. Turaev's question is still open in genus zero.
Diet and gender moderate clozapine-related weight gain

This study examined patients with schizophrenic disorders treated with clozapine in a state hospital setting. Gender and diet affected weight gain over a six-month period. Pre-treatment weight status also related to eventual weight gain. There were no significant effects of dosage. Weight gain was most pronounced in non-dieting women. This has implications for management of patients on clozapine.
An elusive fulvene 1,7,11,24-C60(CF3)4 and its unusual reactivity

The X-ray crystal structure of a trifluoromethylfullerene (TMF), 1,7,11,24-C60(CF3)4, is reported for the first time. This elusive intermediate, while highly air stable as a solid, exhibits highly regioselective reactivity towards molecular oxygen in polar solvents, and only when exposed to light.
Parallel Finite-Difference Migration

Finite-difference migration in the natural x-t coordinates, e.g. the 15-degree implicit wave- equation method, has been in common use for over a decade of geophysical data processing. As such, it predated the invention of large vector computers, such as the Cray-1S introduced in 1977, and so was organized and optimized to achieve the sensible objectives of reducing the number of computations and I/O operations as much as possible. Outboard array processors, employed to accelerate computations, changed the relative weights of computation and I/O but still fit comfortably into existing program designs. Since the mid 80's the author has revisited the implementation of 15-degree implicit finite-difference migration on vector and parallel computers now in common use and found that impressive performance gains can be achieved by completely reorganizing the computations. This report summarizes the highlights of these efforts and gives benchmark results for a variety of vector and parallel platforms.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A ‘greedy’ channel router

Abstract A ‘greedy’ channel-router is presented. It is quick, simple and effective. It always suceeds, usually using no more than one track more than required by channel density. It may be forced in rare cases to make a few connections ‘off the end’ of the channel, in order to succeed. It assumes that all pins and wirling lie on a common grid, and that vertical wires are on one layer, horizontal on another. The greedy router wires the channel left-to-right, column-by-column, wiring each column completely before starting the next. Within each column the router tries to maximize the utility of the wiring produced, using simple, ‘greedy’ heuristics. It may place a net on more than one track for a few columns, and collapse the net to a single track later on, using a vertical jog. It may also use a jog to move a net to a track closer to its pin in some future column. The router may occasionally add a new track to the channel, to avoid getting stuck.
Studies in the Dithienylbenzo[c]thiophene Series

A number of derivatives of 1,3-dithienylbenzo[c]thiophene have been synthesized. The mono- and dicarboxaldehydes have been elaborated to give new vinylenes and cyanovinylenes. β-Dodecyl- and hexyl-substituted analogues have been prepared. Results from cyclic voltammetric investigation as well as fluorescence studies are reported.
A fast multipole method for the evaluation of elastostatic fields in a half-space with zero normal stress

In this paper, we present a fast multipole method (FMM) for the half-space Green's function in a homogeneous elastic half-space subject to zero normal stress, for which an explicit solution was given by Mindlin (Physics 7, 195---202 1936). The image structure of this Green's function is unbounded, so that standard outgoing representations are not easily available. We introduce two such representations here, one involving an expansion in plane waves and one involving a modified multipole expansion. Both play a role in the FMM implementation.
Facile Synthesis of Substituted 2-Iminohydantoins

Abstract A practical method for the preparation of substituted 2-iminohydantoins by cyclization of N-alkoxycarbonyl-α-amino acyl cyanamides is described.
PROSPECTS FOR FURTHER IMPROVEMENT IN ENHANCED HEAT TRANSFER SURFACES.

Abstract The current state-of-the-art of commercial enhanced surfaces for thin film evaporation and condensation on vertical tubes is exemplified by fluted tubes having overall heat-transfer coefficients of 1300 to 2000 Btu/hr ft2 °F at atmospheric pressure. Experimental surfaces have been tested which gave overall coefficients up to 5000 Btu/hr ft2 °F. Oxidative fouling factors as small as 10-4 (Btu/hr ft2 °F)-1 have been reported for fluted enhanced surfaces. It is hypothesized that such small fouling factors occur because high shear forces developed in the thin-film region prevent formation of all except very thin oxide films. Limited data also suggest that the fouling resistance may decrease with increasing heat-transfer coefficient (i.e., with increased shear rate); if true this would provide an important incentive for development of improved enhanced heat transfer surfaces. Although the mechanism responsible for high performance on the condensing side of fluted or finned tubes seems relatively well understood and upper limits can be estimated, the mechanism on the evaporating side seems to be much more complicated. Consequently an upper limit for heat transfer rates on the evaporative side was estimated assuming that the upper limit occurred when the water film thickness was just sufficient to prevent dry spot formation. Assuming a metal wall resistance of 0.00004 and upper limits of 18,000 and 14,200 Btu/hr ft2 °F on the condensing and evaporative sides, respectively, gives an estimated upper limit on performance of enhanced surfaces of ∼6000 Btu/hr ft2 °F.