cssi/SciSciGPT-SciSciNet huggingface dataset:
Is Axillary Lymph Node Dissection Necessary After Sentinel Lymph Node Biopsy in Patients with Mastectomy and Pathological N1 Breast Cancer

The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial reported that axillary lymph node dissection (ALND) did not change the recurrence and overall survival (OS) rates in patients with lumpectomy and one to two positive nodes detected by sentinel lymph node biopsy (SLNB). The aim of this study was to determine whether patients with mastectomy and pathological N1 disease found by SLNB could forego ALND. This is a retrospective study of 214 patients diagnosed with primary invasive breast cancer who were treated by mastectomy and lymph node staging surgery (SLNB or ALND) at the Revlon/UCLA Breast Center between January 2002 and December 2010. Patients with pathological N1 disease were separated by their first nodal surgery into SLNB (subgroups: observation, radiation, and additional ALND with or without radiation) and ALND groups (subgroups: ALND with or without radiation). After a median follow-up of 43.6 months, the OS and systemic relapse-free survival (RFS) rate of the radiation group and additional ALND group were significantly better than the observation group (p = 0.031 and 0.046, respectively). Human epidermal growth factor receptor 2 (HER2) expression was found to predict OS and patients’ age, histological grade and HER2 expression predicted systemic recurrence. Compared with the SLNB group, pain (p = 0.021) and lymphedema (p = 0.043) occurred more frequently in the ALND group. Radiation was as effective as ALND in patients with mastectomy and N1 disease for OS and RFS rates, yet radiation after SLNB had fewer side effects than ALND. SLNB followed by radiation could replace ALND in patients with mastectomy and pathological N1 breast cancer identified by SLNB.
The optimum comb method of pitch period analysis of continuous digitized speech

A new method of tracking the fundamental frequency of voiced speech is described. The method is shown to be of similar accuracy as the Cepstrum technique. Since the method involves only additions, no multiplication, it is shown to be faster than the SIFT algorithm. The basis of the method is searching for a minimum in the magnitude of the difference between a speech segment and a delayed speech segment. This is shown to be equivalent to selecting the comb filter which best annihilates the input signal.
Does the number of houses a broker shows depend on a homeseeker's race?

Abstract Using audit data from the 2000 Housing Discrimination Study and a fixed-effects Poisson model, this paper examines discrimination in the number of houses shown to homeseekers. Unlike previous studies, it considers auditors' actual socioeconomic characteristics to minimize the estimation bias. The results indicate that blacks and Hispanics are shown 30 and 10 percent fewer units, respectively, than whites, whereas there is no similar discrimination against Asians and native Americans. Since 1989, discrimination against blacks has increased by 12 percentage points while discrimination against Hispanics has been unchanged. This paper also finds that brokers discriminate mainly because of white customers' prejudice.
Dynamics of Monatomic Liquids

We present a theory of the dynamics of monatomic liquids built on two basic ideas: (1) the potential surface of the liquid contains three classes of intersecting nearly harmonic valleys, one of which (the `random' class) dominates the potential surface and consists of valleys which all have the same depth and normal-mode spectrum; and (2) the motion of particles in the liquid can be decomposed into oscillations in a single many-body valley, and nearly instantaneous inter-valley transitions called transits. We review the thermodynamic data which led to the theory, and we discuss the results of molecular dynamics (MD) simulations of sodium and Lennard-Jones argon which support the theory in more detail. Then we apply the theory to problems in equilibrium and nonequilibrium statistical mechanics, and we compare the results to experimental data and MD simulations. We also discuss our work in comparison with the quenched normal-mode and instantaneous normal-mode research programmes and suggest directions for future research.
Preparation and Injection of Grout From Spent Shale for Stabilization of Abandoned In-Situ Oil Shale Retorts

A procedure has been developed for stabilizing abandoned in-situ oil shale retorts by means of high-temperature treatment of surface-processed shale, followed by grinding, mixing with water, and injection underground. Laboratory results indicate that abandoned in-situ retorts can be made strong enough to prevent subsidence and sufficiently impermeable to reduce groundwater flow greatly. The underground injection also reduces the amount of spent-shale disposal on the surface. 12 refs.
Preliminary experience with campath 1H (C1H) in intestinal and liver transplantation.

Background The aim of this research was to study the efficacy of campath 1H in combination with low-dose tacrolimus immunosuppression for intestinal, multivisceral, and liver transplantation. Methods Campath 1H (0.3 mg/kg) was administered in four doses: Preoperatively, at the completion of the transplant, and on postoperative days 3 and 7. Tacrolimus levels were maintained between 5 to 10 ng/dL. Suspected or mild rejections were treated with steroids. Moderate or severe rejections were treated with OKT3. Patients We studied three groups of patients: adult recipients of intestinal or multivisceral transplants, high-risk pediatric recipients of small-bowel or multivisceral grafts, and adult liver-transplant recipients. Results Twenty-one adult intestinal recipients received 24 grafts. With follow-up of 2.4 to 16 months, 14 patients are alive and 14 grafts are functioning. Eleven high-risk pediatric intestinal recipients received 12 grafts. There were four mortalities in this group, and after a follow up of 1 to 8.5 months, four patients have not experienced a rejection episode. Five adult liver recipients received five grafts. With a follow-up of 3 to 6.2 months, all five patients are alive. There were no rejection episodes in this group, and none of them required steroid therapy. Conclusions This immunosuppressive regimen allows for the avoidance of maintenance adjuvant-steroid treatment in the majority of our patients. Our preliminary data show a trend toward a reduction of the incidence and the severity of rejection episodes, although we need to follow-up larger numbers of patients to confirm these results.
Stability of ferritic MA/ODS alloys at high temperatures

Abstract The ultrafine scale microstructure of three MA/ODS ferritic alloys (12YWT, 14YWT and MA957) have been characterized by atom probe tomography in the as-received condition and after isothermal heat treatments at temperatures of up to 24 h at 1300 °C (∼85% T m ). Atom probe tomography revealed the presence of a high number density of 2–4 nm diameter titanium-, yttrium- and oxygen-enriched particles. These ultrafine particles were found to be extremely resistant to coarsening during isothermal aging at 1300 °C. Solute segregation of the alloying elements to dislocations and grain boundaries was also observed.
Bulk amorphous metallic alloys: Synthesis by fluxing techniques and properties

Bulk amorphous alloys having dimensions of at least 1 cm in diameter have been prepared in the Pd-Ni-P, Pd-Cu-P, Pd-Cu-Ni-P, and Pd-Ni-Fe-P systems using a fluxing and water-quenching technique. The compositions for bulk glass formation have been determined in these systems. For these bulk metallic glasses, the difference between the crystallization temperature (T x) and the glass transition temperature (T g, ΔT=T x−T g) ranges from 60 to 110 K. These large values of ΔT open the possibility for the fabrication of amorphous near-net-shaped components using techniques such as injection molding. The thermal, elastic, and magnetic properties of these alloys have been studied, and we have found that bulk amorphous Pd40Ni22.5Fe17.5P20 has spin glass behavior for temperatures below 30 K.
Forebody Tangential Slot Blowing on an Aircraft Geometry

The effect of forebody tangential slot blowing on the flowfield about an F/A-18 aircraft is investigated numerically using solutions of the Navier-Stokes equations. Computed solutions are obtained for an aircraft geometry which includes the fuselage, a wing with deflected leading-edge flap, empennage, and a faired-over engine inlet. The computational slot geometry corresponds to that used in full-scale wind-tunnel tests. Solutions are computed using flight test conditions and jet mass flow ratios equivalent to wind-tunnel test conditions. The effect of slot location is analyzed by computing two nontime-accurate solutions with a 16-in. slot located 3 in. and 11 in. aft of the nose of the aircraft. These computations resolve the trends observed in the full-scale wind-tunnel test data. The flow aft of the leading-edge extension vortex burst is unsteady. A time-accurate solution is obtained to investigate the flow characteristics aft of the vortex burst, including the effect of blowing on tail buffet.
Renyi entropy of the interacting Fermi liquid

Entanglement properties, including the Renyi $\ensuremath{\alpha}$ entropies and scaling laws, are becoming increasingly important in condensed-matter physics because they can be used to determine physical properties and the ``fingerprint'' of quantum phases. In this work we use variational quantum Monte Carlo to compute the Renyi $\ensuremath{\alpha}$ entropies, their scaling laws, and the relationship between different $\ensuremath{\alpha}$ entropies for one of the most important phases in condensed matter, the interacting Fermi liquid. We also investigate the relationship between the scaling laws and the discontinuity in the momentum distribution at the Fermi surface. Contrary to recent theoretical predictions, we find that interactions increase the prefactor for the $\ensuremath{\alpha}$-entropy scaling laws for all particle interaction strengths and forms. We also show that a theory of these scaling laws for the interacting systems may be developed by extending the free theory to incorporate properties of the momentum distribution.
Synthesis of [L-3-Deoxymimosine4]-angiotensin I as an approach to the preparation of selective protein-tyrosine kinase (PTK) inhibitors

Abstract tert-Boc-L-3-Deoxymimosine (13) and tert-Boc-D-Deoxymimosine (16) were prepared in two steps from tert-Boc-L-asparagine and tert-Boc-D-asparagine, respectively. Both 13 and 16 were determined to be optically pure by derivatization with Marphey's reagent. Activation and coupling of 16 to L-isoleucine methyl ester resulted in a diastereomeric mixture of products containing 96% of the DL diastereomer and 4% of the LL diastereomer. [L-3-Deoxymimosine4]-angiotensin I was synthesized from 13 as an approach to the design and synthesis of selective protein-tyrosine kinase (PTK) inhibitors.
Product-line selection, production decisions and allocation of common fixed costs

Abstract Product costs are determined in practice for the purpose of pricing, make-buy and product-line decisions. While many costs are directly assignable to individual products, common costs have historically presented a difficult conundrum. A variety of cost allocation methods are used in practice, or have been suggested in the literature, to attach these costs to individual products. While such procedures are theoretically unsupported, they may be able to mimic the “correct” decisions adequately. In this paper, we investigate the efficacy of certain cost allocation schemes in a competitive environment. The schemes are evaluated with reference to a scenario in which there is a single fixed cost incurred in manufacturing any subset of a set of products. Under idealized conditions, a Cournot-Nash model is developed that describes the number of entering firms and the equilibrium price and production levels. Using this as a point of reference, it is shown that by using gross contribution as an allocation basis, optimal product-line decisions are achieved, without distorting the selection of production levels. Moreover, competitive pressure sufficient to drive total net profits close to zero is sufficient to require that any allocation rule supporting optimal product-line decisions yields allocations nearly proportional to gross contributions. An analogy is drawn with the allocation of joint costs to coproducts in a competitive environment, and the corresponding allocation in proportion to net realizable value.
Restart Strategies and Internet Congestion

Abstract We recently presented a methodology to quantitatively reduce the average time and variance in the time required to execute electronic transactions in a network environment such as the Internet. In the language of portfolio theory, time to complete a transaction and its variance replace the expected return and risk associated with a security, whereas restart times replace combinations of securities. While such a strategy works well with single users, the question remains as to its usefulness when used by many. By using mean field arguments and agent-based simulations, we determine that a restart strategy remains advantageous even when everybody uses it.
A Pulse-Injection-Based Sensorless Position Estimation Method for a Switched Reluctance Machine Over a Wide Speed Range

In this paper, a pulse-injection-based method for determining the rotor position of a switched reluctance motor (SRM) over its entire speed range is presented. In this method, a single high-frequency pulse is injected in an idle phase to determine the rotor position at high speeds. The proposed method estimates the rotor position through analysis of the resultant current after voltage pulse injection. A low-speed sensorless method previously developed based on pulse injection has also been extended to improve robustness against varying operating conditions. The developed pulse injection with varying duty ratios provided uniform sensing thresholds over varying dc bus voltages. The low- and high-speed methods are integrated together to provide a robust wide-speed-range rotor position estimator for SRM.
The origin of deuterium

General nuclear constraints are used to show that deuterium is most likely of pregalactic origin. Big-bang nucleosynthesis is the most plausible source for significant amounts of this isotope, but other, more speculative, sources are not ruled out.
STELLAR POPULATIONS FROM SPECTROSCOPY OF A LARGE SAMPLE OF QUIESCENT GALAXIES AT Z > 1: MEASURING THE CONTRIBUTION OF PROGENITOR BIAS TO EARLY SIZE GROWTH

We analyze the stellar populations of a sample of 62 massive (log M_∗/M_⊙ > 10.7) galaxies in the redshift range 1 < z < 1.6, with the main goal of investigating the role of recent quenching in the size growth of quiescent galaxies over the redshift range 1.25 < z < 2 where the apparent growth is particularly rapid. We demonstrate that our sample is not biased toward bright, compact, or young galaxies, and thus is representative of the overall quiescent population. Our high signal-to-noise ratio Keck LRIS spectra probe the rest-frame Balmer break region which contains important absorption line diagnostics of recent star formation activity. We show that improved measures of the various stellar population parameters, including the star-formation timescale τ, age and dust extinction, can be determined by fitting templates jointly to both our spectroscopic and broad-band photometric data. These parameter fits allow us to backtrack the evolving trajectory of individual galaxies on the UV J color-color plane. In addition to identifying which quiescent galaxies were recently quenched, an effect often termed progenitor bias in studies of the evolution of this population, we discover important variations in the star formation history of quiescent galaxies indicating the likelihood of more than one quenching route. By using sizes measured in the previous paper of this series, we confirm that the largest galaxies are indeed among the youngest at a given redshift, an effect consistent with some contribution to the apparent growth from recent arrivals. However, we calculate that recently-quenched objects can only be responsible for about half of the increase in the average size of quiescent galaxies over a 1.5 Gyr period corresponding to the redshift interval 1.25 < z < 2. The remainder of the observed size evolution arises from a genuine growth of long-standing quiescent galaxies. We discuss the prospects of determining whether the combination of minor merging and progenitor bias can explain the remarkably fast apparent growth rate during this short period of cosmic history.
Isogeny classes of abelian varieties over function fields

We study finiteness problems for isogeny classes of abelian vari- eties over an algebraic function field K in one variable over the field of complex numbers. In particular, we construct explicitly a non-isotrivial absolutely sim- ple abelian fourfold X over a certain K such that the isogeny class of X× X contains infinitely many mutually non-isomorphic principally polarized abelian varieties. (Such examples do not exist when the ground field is finitely gener- ated over its prime subfield.) 2000 Mathematics Subject Classification 14K02 (primary), 14D07 (sec- ondary)
Discovery of the vanadium isotopes

Twenty-four vanadium isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
Resonant bound state production at e−e− colliders

Abstract Observation of a sequence of resonances at an e − e − collider would suggest bound states of strongly coupled constituents carrying lepton number. Obvious candidates for these exotic constituents are leptoquarks and leptogluons. We show that under reasonable assumptions, the existence of one leptogluon flavor of appropriate mass can give rise to sizable “leptoglueball” production rates and observable resonance peaks. In contrast, one needs two leptoquark flavors in order to produce the analogous “leptoquarkonium” states. Moreover, cross-generational leptoquark couplings are necessary to give observable event rates in many cases, and leptoquarkonium mass splittings are too small to resolve with realistic beam energy resolutions.
A LAGUERRE POLYNOMIAL ORTHOGONALITY AND THE HYDROGEN ATOM

The radial part of the wave function of an electron in a Coulomb potential is the product of a Laguerre polynomial and an exponential with the variable scaled by a factor depending on the degree. This note presents an elementary proof of the orthogonality of wave functions with differing energy levels. It is also shown that this is the only other natural orthogonality for Laguerre polynomials. By expanding in terms of the usual Laguerre polynomial basis, an analogous strange orthogonality is obtained for Meixner polynomials.
Homology of holomorphs of free groups

The holomorph of a free group Fn is the semidirect product Fn⋊Aut(Fn). Using the methods of Hatcher and Vogtmann in [J. London Math. Soc. (2) 58 (1998) 633–635 and Math. Res. Lett. 5 (1998) 759–780], we derive stability results and calculate the mod-p homology of these holomorphs for odd primes p in dimensions 1 and 2, and their rational homology in dimensions 1 through 5. Calculations of the twisted (where Aut(Fn) acts by first projecting to Gln(Z) and then including in Gln(Q)) homology H∗(Aut(Fn);Qn) follow in corresponding dimensions.
Statistical mechanics of base stacking and pairing in DNA melting

We propose a statistical mechanics model for DNA melting in which base stacking and pairing are explicitly introduced as distinct degrees of freedom. Unlike previous approaches, this model describes thermal denaturation of DNA secondary structure in the whole experimentally accessible temperature range. Base pairing is described through a zipper model, base stacking through an Ising model. We present experimental data on the unstacking transition, obtained exploiting the observation that at moderately low pH this transition is moved down to experimentally accessible temperatures. These measurements confirm that the Ising model approach is indeed a good description of base stacking. On the other hand, comparison with the experiments points to the limitations of the simple zipper model description of base pairing.
Hepatic Microsomal Induction in Rat Liver: Heterogeneity of Response

: The concept that urinary 6-hydroxycortisol excretion patterns reflect all microsomal enzyme activities remains a subject of controversy. Three different microsomal hydroxylase activities were therefore studied in rat liver after the animals were intoxicated with alcohol, phenobarbital, or a combination thereof. The activities of pentobarbital hydroxylase, aniline hydroxylase, and cortisol 6-hydroxylase (the enzyme metabolizing cortisol to 6-hydroxycortisol) were assayed simultaneously after each treatment. A heterogeneity of enzyme activities was noted. Cortisol 6-hydroxylase activity did not parallel the activity patterns of the two other hydroxylases. The data suggest that before urinary 6-hydroxycortisol excretion patterns can be utilized as an index of microsomal enzyme induction, the effect of the specific drug on individual cytochrome P-450 hydroxylases is required.
Hybrid diffractive-refractive telescope

Telescopes, microscopes, and similar compound systems often require achromats for objectives, since the longitudinal chromatic aberration from a singlet objective is so large that eyepieces cannot easily correct it. Such achromats can limit large-aperture systems because the curvatures required of their components are much stronger than the curvatures of singlets with the same net optical power. The hybrid diffractive-refractive telescope formed by combining a diffractive eyepiece with an unachromatized refractive objective is shown to eliminate the need for such bulky objectives, since a diffractive eyepiece is capable of correcting the large longitudinal chromatic aberrations of singlet refractive objectives. By splitting the holographic eyepiece into two elements, paraxial lateral color may also be corrected. First-order design considerations in these hybrid telescopes are presented, and a practical hybrid telescope layout is developed in which 1) primary chromatic aberration is eliminated, 2) paraxial lateral color is corrected, and 3) a useful eye relief is obtained.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A breathing circuit alarm system based on neural networks.

Objective. The objectives of our study were (1) to implement intelligent respiratory alarms with a neural network; and (2) to increase alarm specificity and decrease false-alarm rates compared with current alarms.Methods. We trained a neural network to recognize 13 faults in an anesthesia breathing circuit. The system extracted 30 breath-to-breath features from the airway CO2, flow, and pressure signals. We created training data for the network by introducing 13 faults repeatedly in 5 dogs (616 total faults). We used the data to train the neural network using the backward error propagation algorithm.Results. In animals, the trained network reported the alarms correctly for 95.0% of the faults when tested during controlled ventilation, and for 86.9% of the faults during spontaneous breathing. When tested in the operating room, the system found and correctly reported 54 of 57 faults that occurred during 43.6 hr of use. The alarm system produced a total of 74 false alarms during 43.6 hr of monitoring.Conclusion. Neural networks may be useful in creating intelligent anesthesia alarm systems.
Career education in business data processing teacher education

The career path for teachers of business data processing has virtually been non-existent in the State of Oklahoma. Higher education institutions, however, have offered some coursework in data processing since 1958. Most of these courses were designed for scientific applications oriented toward the physicist and engineer.
Apollo: Learning From the Past, For the Future

This paper shares an interesting and unique case study of knowledge capture by the National Aeronautics and Space Administration (NASA), an ongoing project to recapture and make available the lessons learned from the Apollo lunar landing project so that those working on future projects do not have to "reinvent the wheel". NASA's new Constellation program, the successor to the Space Shuttle program, proposes a return to the Moon using a new generation of vehicles. The Orion Crew Vehicle and the Altair Lunar Lander will use hardware, practices, and techniques descended and derived from Apollo, Shuttle and the International Space Station. However, the new generation of engineers and managers who will be working with Orion and Altair are largely from the decades following Apollo, and are likely not well aware of what was developed in the 1960s. In 2006 a project at NASA's Johnson Space Center was begun to find pertinent Apollo-era documentation and gather it, format it, and present it using modern tools for today's engineers and managers. This "Apollo Mission Familiarization for Constellation Personnel" project is accessible via the web from any NASA center for those interested in learning "how did we do this during Apollo?"
Tuning the polarization-induced free hole density in nanowires graded from GaN to AlN

We report a systematic study of p-type polarization-induced doping in graded AlGaN nanowire light emitting diodes grown on silicon wafers by plasma-assisted molecular beam epitaxy. The composition gradient in the p-type base is varied in a set of samples from 0.7%Al/nm to 4.95%Al/nm corresponding to negative bound polarization charge densities of 2.2 × 1018 cm−3 to 1.6 × 1019 cm−3. Capacitance measurements and energy band modeling reveal that for gradients greater than or equal to 1.30%Al/nm, the deep donor concentration is negligible and free hole concentrations roughly equal to the bound polarization charge density are achieved up to 1.6 × 1019 cm−3 at a gradient of 4.95%Al/nm. Accurate grading lengths in the p- and n-side of the pn-junction are extracted from scanning transmission electron microscopy images and are used to support energy band calculation and capacitance modeling. These results demonstrate the robust nature of p-type polarization doping in nanowires and put an upper bound on the magnitu...
Water Corrosion of YBa2Cu3O7−δ Superconductors

Solid-state sintering was used to make YBa2Cu3O7−δ superconducting bulk materials. Corrosion of the YBa2Cu3O7−δ superconductor material was investigated in a humid environment. The superconducting materials exhibited significant corrosion after 4 h at 80° and 100% relative humidity. A grain-boundary phase was formed, and the percent superconducting phase in the material decreased by approximately 60%. The transition temperature (Tc) decreased with corrosion time. After 2 h of corrosion, Tc decreased from 87 to 81 K.
Hot interstellar tunnels. I - Simulation of interacting supernova remnants

The theory required to build a numerical simulation of interacting supernova remnants is developed. The hot cavities within a population of remnants will become connected, with varying ease and speed, for a variety of assumed conditions in the outer shells of old remnants. Apparently neither radiative cooling nor thermal conduction in a large-scale galactic magnetic field can destroy hot cavity regions, if they grow, faster than they are reheated by supernova shock waves, but interstellar mass motions disrupt the contiguity of extensive cavities necessary for the dispersal of these shocks over a wide volume. Monte Carlo simulations show that a quasi-equilibrium is reached in the test space within 10 million yrs of the first supernova and is characterized by an average cavity filling fraction of the interstellar volume. Aspects of this equilibrium are discussed for a range of supernova rates. Two predictions are not confirmed within this range: critical growth of hot regions to encompass the entire medium, and the efficient quenching of a remnant's expansion by interaction with other cavities.
On the Electronic Structure and Chemical Bonding in the Tantalum Trimer Cluster

The electronic structure and chemical bonding in the Ta3- cluster are investigated using photoelectron spectroscopy and density functional theory calculations. Photoelectron spectra are obtained for Ta3- at four photon energies: 532, 355, 266 and 193 nm. While congested spectra are observed at high electron binding energies, several low-lying electronic transitions are well resolved and compared with the theoretical calculations. The electron affinity of Ta3 is determined to be 1.35±0.03 eV. Extensive density functional calculations are performed at the B3LYP/Stuttgart +2f1g level to locate the ground state and low-lying isomers for Ta3 and Ta3-. The ground state for the Ta3- anion is shown to be a quintet (5A1') with D3h symmetry, whereas two nearly isoenergetic states, C2v (4A1) and D3h (6A1'), are found to compete for the ground state for neutral Ta3. A detailed molecular orbital analysis is performed to elucidate the chemical boding in Ta3-, which is found to possess multiple d-orbital aromaticity, commensurate with its highly symmetric D3h structure.
A Meshalkin theorem for projective geometries

Let M be a family of sequences (a1,..., ap) where each ak is a flat in a projective geometry of rank n (dimension n- 1) and order q, and the sum of ranks, r(a1)+ ... + r(ap), equals the rank of the join a1 ∨ ... ∨ ap. We prove upper bounds on |M| and corresponding LYM inequalities assuming that (i) all joins are the whole geometry and for each k < p the set of all ak's of sequences in M contains no chain of length l, and that (ii) the joins are arbitrary and the chain condition holds for all k. These results are q-analogs of generalizations of Meshalkin's and Erdos's generalizations of Sperner's theorem and their LYM companions, and they generalize Rota and Harper's q-analog of Erdos's generalization.
Vibration Control in Rotating or Translating Elastic Systems

The reduction of vibration in rotating or translating elastic systems (e.g., shafts, circular saws, belts, handsaws) is an important engineering problem. This paper presents the characteristics of rotating or translating elastic system vibration problems which are significant for the design of active controllers. The effect of the rotation or translation velocity on the controller design, and the effects of observation and control spillover are discussed. Simulation results for two example problems, a rotating cantilever shaft and an axially moving string, are used to illustrate the design and performance of active vibration controllers for rotating or translating elastic systems.
Asymmetric Hydrogenation of Aryl Ketones Mediated by a Copper Catalyst

[reaction: see text] A novel asymmetric hydrogenation protocol using a copper catalyst is reported. A Cu(I) complex in the presence of nonracemic BDPP hydrogenates aryl ketones with moderate to high enantioselectivity.
On the Integrated Squared Error of the Linear Wavelet Density Estimator

Abstract The object of this paper is to study some asymptotic properties of the integrated squared error of a linear wavelet density estimator, ∥ f ^ n − f ∥ L 2 ( R ) 2 . We provide the exact almost sure rate of concentration about its mean, in fact a law of the iterated logarithm. Regarding the rate in probability, we obtain a polynomial upper bound for the rate of convergence in the central limit theorem of Zhang and Zheng (1999) .
The Maspar Mp-1 as a Computer Arithmetic Laboratory

This paper is a blueprint for the use of amassively parallel SIMD computer architec-ture for the simulation of various forms ofcomputer arithmetic. The particular systemused is a DEC/MasPar MP-1 with 4096processors in a square array. This architec-ture has many advantages for such simula-tions due largely to the simplicity of the in-dividual processors. Arithmetic operationscan be spread across the processor array tosimulate a hardware chip. Alternativelythey may be performed on individual pro-cessors to allow simulation of a massivelyparallel implementation of the arithmetic.Compromises between these extremespermit speed-area tradeoffs to be examined.The paper includes a description of thearchitecture and its features. It then sum-marizes some of the arithmetic systemswhich have been, or are to be, imple-mented. The implementation of the level-in-dex and symmetric level-index, LI and SLI,systems is described in some detail. An ex-tensive bibliography is included.Key words: computer arithmetic; fixed-point and floating-point arithmetic;logarith-mic and level-index arithmetic; residuenumber system arithmetic; serial and paral-lel simulation of computer arithmetic.Accepted: November 15, 1995
Reduction of BTZ spacetime to hypersurfaces of foliation

We reduce the BTZ spacetime to two kinds of hypersurfaces of foliation: one having a fixed radial coordinate and the other a fixed angular coordinate. The radial reduction leads to a Liouville type theory, and confirms, from the first principle, the expectation laid out in the literature. In the other endeavor, the angular reduction of the 3D gravity is carried out in two different ways; the first again yields a Liouville type theory (different from that of the radial reduction) and the second yields a 2D interacting quantum field theory with quartic potential. We discuss potential implications of our result for the Equivalence Principle and Purity of Hawking radiation.
Common threads: epigenetics, metabolism and the clock

Circadian rhythms govern a number of fundamental physiological functions in almost all organisms, from prokaryotes to humans. The circadian clocks are intrinsic time-tracking systems with which organisms can anticipate environmental changes and adapt to the appropriate time of day. Disruption of these rhythms can have a profound influence to human health and has been linked to depression, insomnia, jet lag, coronary heart disease, neurodegenerative disorders and cancer. At the heart of circadian regulatory pathways is the clock machinery, a remarkably coordinated transcription-translation system that utilizes also dynamic changes in chromatin transitions and epigenetic control. Recent findings indicate that regulation goes also the other way, since specific elements of the clock are able to sense changes in the cellular metabolism. Understanding in full detail the intimate links between cellular metabolism and the circadian clock machinery will provide not only critical insights into system physiology and endocrinology, but also novel avenues for pharmacological intervention towards metabolic disorders.
Trauma in Pregnancy: Predicting Pregnancy Outcome

The pregnant trauma victim presents a unique challenge to the resuscitating physician because two patients are being treated. Trauma is the most frequent nonobstetric cause of death in the gravid patient, occuring in about 7% of all pregnancies. As pregnancy progresses, gait instability secondary to pelvic ligamentous laxity, increasing abdominal protuberance, and shifting of the center of gravity contribute to an increased risk of trauma. This risk is well recognized and has prompted a systematic approach to the treatment of the injured pregnant patient.
Experimental study of a confined jet thrust vector control nozzle

An experimental study of a confined jet thrust vector control (CJTVC) nozzle is described. A CJTVC nozzle uses secondary injection for controlling and vectoring an overexpanded, supersonic jet within a confining chamber of the nozzle. This chamber consists of a diverging region and a region downstream that reconverges to an orifice at the exit. The pressure in the jet confining chamber can exceed ambient pressure. In this study, axial thrust is shown to depend on primary pressure, whereas side force and thrust vectoring are shown to depend on primary pressure, secondary injection pressure, and secondary port area. Only a small amount of secondary flow, compared with primary flow, is required for thrust vectoring. Unstable operation is found to occur under some conditions.
The Optimal Trading and Pricing of Securities with Asymmetric Capital Gains Taxes and Transaction Costs

This article explores the optimal trading and pricing of taxable securities with asymmetric capital gains taxes and transaction costs. In the long-term region, investors realize all gains below some critical cutoff level, which we derive analytically. In the short-term region, investors defer all gains and, depending upon the time remaining in the short-term region, may also defer small losses. Contrary to common intuition, deferral of short-term losses can be optimal even without transaction costs. The value of tax timing is considerably bigger under the optimal trading strategy than under alternative strategies previously analyzed. The impact of offset rules is also explored. Article published by Oxford University Press on behalf of the Society for Financial Studies in its journal, The Review of Financial Studies.
ZPC 1.0.1: A Parton cascade for ultrarelativistic heavy ion collisions

A Monte Carlo program solving the Boltzmann equation for partons via the cascade method is presented. At presented, only gluon-gluon elastic scattering is included. The scattering cross section is regulated by a medium generated screening mass. Three different geometric modes (3-dimensional expansion, 1-d expansion, and scattering inside a box) are provided for both the theoretical study of parton transport and the application of the cascade method. Space cell division is available to save the number of computer operations. This improves the speed of the calculation by a large factor and makes the code best optimized for simulation of parton cascade in ultrarelativistic heavy ion collisions.
MAGNETOHYDRODYNAMIC SHALLOW WATER WAVES: LINEAR ANALYSIS

We present a linear analysis of inviscid, incompressible, magnetohydrodynamic (MHD) shallow water systems. In spherical geometry, a generic property of such systems is the existence of five wave modes. Three of them (two magneto-Poincare modes and one magneto-Rossby mode) are previously known. The other two wave modes are strongly influenced by the magnetic field and rotation, and have substantially lower angular frequencies; as such, we term them "magnetostrophic modes." We obtain analytical functions for the velocity, height, and magnetic field perturbations in the limit that the magnitude of the MHD analogue of Lamb's parameter is large. On a sphere, the magnetostrophic modes reside near the poles, while the other modes are equatorially confined. Magnetostrophic modes may be an ingredient in explaining the frequency drifts observed in Type I X-ray bursts from neutron stars.
The Origins and Evolutionary Status of B Stars Found Far from the Galactic Plane. II. Kinematics and Full Sample Analysis

This paper continues the analysis of faint high-latitude B stars from Martin. Here we analyze the kinematics of the stars and combine them with the abundance information from the first paper to classify each one. The sample contains 31 Population I runaways, 15 old evolved stars (including 5 blue horizontal-branch [BHB] stars, 3 post-HB stars, 1 pulsating helium dwarf, and 6 stars of ambiguous classification), 1 F dwarf, and 2 stars that do not easily fit in one of the other categories. No star in the sample unambiguously shows the characteristics of a young massive star formed in situ in the halo. The two unclassified stars are probably extreme Population I runaways. The low binary frequency and rotational velocity distribution of the Population I runaways imply that most were ejected from dense star clusters by the dynamic ejection scenario. However, we remain puzzled by the lack of runaway Be stars. We also confirm that PB 166 and HIP 41979 are both nearby solar-metallicity BHB stars.
In-Plane Fracture of Laminated Fiber Reinforced Composites with Varying Fracture Resistance: Experimental Observations and Numerical Crack Propagation Simulations

A series of experimental results on the in-plane fracture of a laminated composite panel is analyzed using the variational multi-scale cohesive method (VMCM). The VMCM results demonstrate the influence of specimen geometry and load distribution on the propagation of large scale bridging cracks in laminated fiber reinforced composites. Experimentally observed variation in fracture resistance is substantiated numerically by comparing the experimental and VMCM load-displacement responses of geometrically scaled single edgenotch three point bend (SETB) specimens. The results elucidate the size dependence of the traction-separation relationship for this class of materials even in moderately large specimens, contrary to the conventional understanding of it being a material property. The existence of a “free bridging zone” (different from the conventional “full bridging zone”) is recognized, and its influence on the evolving fracture resistance is discussed. The numerical simulations and ensuing bridging zone evolution analysis demonstrates the versatility of VMCM in objectively simulating progressive crack propagation, compared against conventional numerical schemes like traditional cohesive zone modeling, which require a priori knowledge of the crack path.
Oxidation of bicyclic oxazolines: applications to glycomimetics and novel saccharide derivatives

A general procedure is reported for the oxidation of substituted oxazolines to α-acyloxyketoximes and the derived α-acyloxyketones. In the case of oxazolines derived from 2-acetamido-2-deoxyhexoses, the resulting 2-oximinoesters can be converted to 2-nitroglycals.
Millimeter and submillimeter wave absorption by atmospheric pollutants and constituents

Calculated absorption coefficients and rotational transition frequencies ara given for a number of polar molecules of interest to pollution and energy research. The results, which are presented in graphical form for microwave frequencies up to 1400 GHz, illustrate the increased absorption line intensities occurring in the submillimeter region. For most species, these absorption coefficients attain their maximum values in this region. Included in the calculations are SO2, H2CO, O3, H2O, H2S, OCS, CO, NO, OH, SO, NH3, and CS. A discussion of the techniques currently available for detection in the submillimeter region of these species is also given.
The Disk and Dark Halo Mass of the Barred Galaxy NGC 4123. I. Observations

The noncircular streaming motions in barred galaxies are sensitive to the mass of the bar and can be used to lift the degeneracy between disk and dark matter halo encountered when fitting axisymmetric rotation curves of disk galaxies. In this paper we present photometric and kinematic observations of NGC 4123, a barred galaxy of modest size (Vrot = 130 km s-1, L = 0.7L*), that reveal strong noncircular motions. The bar has straight dust lanes and an inner Lindblad resonance. The disk of NGC 4123 has no sign of truncation out to 10 scale lengths, and star-forming regions are found well outside R25. A Fabry-Perot Hα velocity field shows velocity jumps of greater than 100 km s-1 at the location of the dust lanes within the bar, indicating shocks in the gas flow. VLA observations yield the velocity field of the H I disk. Axisymmetric mass models yield good fits to the rotation curve outside the bar region for disk I-band M/L of 2.25 or less, and dark halos with either isothermal or power-law profiles can fit the data well. In a companion paper we model the full two-dimensional velocity field, including noncircular motions, to determine the stellar M/L and the mass of the dark halo.
Capture of bulk geodesics by brane-world black holes

In this letter we study bulk time-like geodesics in the presence of a brane-world black hole, where the brane-world is a two-brane moving in a (3+1)-dimensional asymptotically adS4 spacetime. We show that for a certain range of the parameters measuring the black hole mass and bulk cosmological constant, there exist stable time-like geodesics which orbit the black hole and remain bound close to the two-brane.
Inconsistencies between lifetime and polarizability measurements in Cs

Electric dipole matrix elements for , , , , transitions in cesium are calculated using a relativistic all-order method. The resulting matrix elements are used to evaluate lifetimes and polarizabilities. The data are compared with experimental lifetime and polarizability measurements made by different groups. Domination of the scalar polarizabilities by dipole matrix elements facilitates an exacting consistency check of lifetime and polarizability data. Values of matrix elements obtained from experimental lifetime data are found to be inconsistent with those inferred from polarizabilities derived from experimental Stark shift data. Our calculated polarizabilities agree well with experimental determinations.
Aspects and applications of patched grid calculations

Patched grid calculations within the framework of an implicit, flux-vector split upwind/relaxation algorithm for the Euler equations are presented. The effect of a metric-discontinuous interface on the convergence rate of the algorithm is discussed along with the spatial accuracy of the solution and the effect of curvature along an interface. Results are presented and discussed for the free-stream problem, shock reflection problem, supersonic inlet with a 5 degree ramp, aerodynamically choked inlet, and three-dimensional analytic forebody.
Chemical Erosion of Refractory-Metal Nozzle Inserts in Solid-Propellant Rocket Motors

An integrated theoretical/numerical framework is established and validated to study the chemical erosion of refractory-metal (tungsten, rhenium, and molybdenum) nozzle inserts in solid-rocket-motor environments, with a primary focus on tungsten. The formulation takes into account multicomponent thermofluid dynamics in the gas phase, heterogeneous reactions at the surface, energy transport in the solid phase, and nozzle material properties. Typical combustion species of nonmetallized ammonium-perchlorate/hydroxyl-terminated-polybutadiene propellants at practical motor operating conditions are considered. The erosion rates calculated by employing three different sets of chemical kinetics data available in the literature for the tungsten-steam reaction have been compared. The effect of considering either of two different tungsten oxides, WO2 or WO3, as the final product of surface reactions is also investigated. The predicted erosion rates compare well with experimental data. The oxidizing species of H2O proved more detrimental than CO2 in dictating the tungsten nozzle erosion. The material recessionrateiscontrolledbyheterogeneouschemicalkineticsbecausethediffusionlimitisnotreached.Theerosion rate increases with increasing chamber pressure, mainly due to higher convective heat transfer and enhanced heterogeneous surface reactions. The tungsten nozzle erodes much more slowly than graphite, but at a rate comparable with that of rhenium. The molybdenum nozzle exhibits the least erosion for flame temperatures lower than 2860 K. Its low melting temperature (2896 K), however, restricts applications for propellants with high flame temperatures.
Mars Lander Position Estimation in the Presence of Ephemeris Biases

The process of estimating the location of a spacecraft landed on the surface of Mars is investigated through the application of statistical estimation techniques to earth-based radio tracking data. The spacecraft location and the tracking geometry and schedule are consistent with Viking-type mission constraints. With mission control requirements in mind, the investigation is restricted to analysis of a short data arc (approximately 3 days). Statistics of the spacecraft location are obtained through analysis of (direct-link) tracking data for the landed spacecraft and through simultaneous analysis of tracking data for both a landed and an orbiting spacecraft. These estimates include the effects of model uncertainties in the ephemeris of Mars, tracking station locations, the Mars rotational period, the Mars gravity field, and the orientation of Mars axis of rotation. The most significant of these effects is shown to be due to the Mars ephemeris uncertainty. A dual spacecraft tracking technique is presented for substantially reducing these ephemeris effects.