cssi/SciSciGPT-SciSciNet huggingface dataset:
Interstellar flight by particle beam

Abstract Two difficulties with the use of laser-propelled lightsails for interstellar propulsion are the extremely low energy efficiency, and the extremely large lenses required. The energy efficiency can be greatly increased and the required lens size may be greatly decreased by use of a particle beam, rather than a light beam. The particle beam is reflected by a magnetic field on the spacecraft, for example, by a magnetic sail or a mini-magnetosphere inflated by a plasma current. This results in a net force on the sail with no expenditure of propellant, allowing missions of extremely high delta-V, such as an interstellar probe, to be accomplished. Compared to other beam-pushed propulsion systems, the particle-beam pushed sail has the advantages of light weight, high target area, high thermally limited acceleration, high momentum to energy ratio, high beam energy efficiency, and low beam divergence.
Surveillance after curative colon cancer resection: practice patterns of surgical subspecialists.

Background: In the literature, suggested strategies for the follow-up of colon cancer patients after potentially curative resections vary widely. The optimal regimen to monitor for recurrences and new primary tumors remains unknown. The nationwide cost impact of wide practice variation is also unknown.
Unifying the controlling mechanisms for the critical heat flux and quenching : the ability of liquid to contact the hot surface

We investigated the hypothesis that the critical heat flux (CHF) occurs when some point on a heated surface reaches a temperature high enough that liquid can no longer maintain contact at that point, resulting in a gradual but continuous increase in the overall surface temperature for most power-controlled systems. This hypothesis unifies the occurrence of the CHF with the quenching of hot surfaces by relating them to the same concept: the ability of a liquid to contact a hot surface, generally defined as some fraction of the liquid's homogeneous nucleation temperature, depending on the contact angle. The proposed hypothesis about the occurrence of the CHF is investigated through a study of the boiling mechanism of the second transition region of nucleate pool boiling of water on copper. An idealized two-dimensional transient conduction heat transfer model was developed to investigate the heat transfer mechanism. The initial macrolayer thickness on the dry portion of the heater, in the second transition region, was found to be bounded between 0 and 11 [mu]m. The radius of the dry patch varied from 15 to 23 mm (60 and 92 percent of the heater radius, respectively) for initial macrolayer thicknesses of 0 and 11 tim, respectively.more » The results indicated that the critical liquid-solid contact temperature at the onset of CHF (the surface temperature at the center of the dry patch) must be lower than the homogeneous nucleation temperature of the liquid for the pool boiling of water on a clean horizontal surface. The liquid-solid contact Temperature was dependent on the initial dry patch liquid macrolayer thickness, varying from 180[degrees]C to 157[degrees]C for initial macrolayer thicknesses of 0 and 11 [mu]m, respectively. Independent assessment of these values shows good agreement with extrapolated contact temperature data at the onset of film boiling.« less
Indications and Outcomes of Double Free Flaps in Head and Neck Reconstruction

Methods: A retrospective review at two tertiary referral centers was performed. Patient demographics, cancer characteristics, methods of reconstruction, and postoperative course were recorded. All patients were assessed for diet, speech, esthetics, socialization, and satisfaction using specific evaluation scales. Results: A total of 30 patients underwent double free flap reconstruction between 2001 and 2007. There were 19 men and 11 women, mean age of 62 years (range, 42-79). Comorbidities were present in 67%, and 70% smoked. Most frequently the cancer was squamous cell carcinoma (90%), in advanced stage (87%), and recurrent (67%), affecting the oral cavity (43%), larynx (23%) or pharynx (20%). The fibula osteoseptocutaneous/ radial forearm fasciocutaneous flap combination was most commonly used (n=13), followed by the jejunum-radial forearm flap (n=10). Three flaps required early anastomosis revision and only two partial flap losses were observed. In 11 cases, there was a severe recipient site complication: wound dehiscence (n=3), oral incompetence (n=4), fistula (n=2), and stenosis (n=2). Two patients died in the postoperative period due to medical problems (7%). The mean follow up was 15.3 months. Patient satisfaction was poor to moderate and the overall functional evaluation score was low.
Multi-core demands multi-interfaces

The challenge for the microarchitect has always been (with very few notable domain-specific exceptions) how to translate the continually increasing processing power provided by Moore's Law into increased performance, or more recently into similar performance at lower cost in energy. The mechanisms in the past (almost entirely) kept the interface intact and used the increase in transistor count to improve the performance of the microarchitecture of the uniprocessor. When that became too hard, we went to larger and larger on-chip caches. Both are consistent with the notion that "abstractions are good." At some point, we got overwhelmed with too many transistors; predictably, multi-core was born. As the transistor count continues to skyrocket, we are faced with two questions: what should be on the chip, and how should the software interface to it. If we expect to continue to take advantage of what process technology is providing, I think we need to do several things, starting with rethinking the notion of abstraction and providing multiple interfaces for the programmer.
Performance Attribution of US Institutional Investors

Institutional investors play a prominent role in today's markets. Quarterly reported portfolio holdings make it possible to evaluate the risk-adjusted equity investment performance of all institutional investors in the United States during 1981–2002. The results indicate that institutional investors have been successful in managing client assets; they have added significant value by generating excess returns after controlling for underlying portfolio risk factors. Style choice is the main factor in determining overall portfolio performance, but institutional investors also displayed significant stock selection skills during the period. The stocks they choose for their portfolios have outperformed the stocks they exclude.
Critical factors in chemical characterization for the evaluation of decontamination in solids using advanced oxidation

Advanced oxidation technologies (AOT) have been applied to the treatment of numerous organic pollutants embedded in solid matrices (e.g., soil, sediments, sludge, etc.). Given potentially strong matrix-analyte interactions in solids, chemical characterization of both the target contaminants and their oxidation products is critical for the evaluation of any decontamination method. The success of AOT applications has been evaluated either directly (based on the removal of original contaminants, extent of mineralization, and/or formation of by-products), or indirectly, e.g., based on toxicity or chemical oxygen demand. Since indirect methods do not provide comprehensive understanding of the pollutants' fate, direct analytical approaches are covered in this review while focusing on sample preparation and detailed chromatographic characterization, assessing the strengths and weaknesses of these methods. The significance of sample preparation, in particular extraction, is discussed with respect to the nature of matrix-analyte interactions, as those may also affect the selection of the remediation method. The ultimate goal of this review is the presentation of methods employed to achieve mass balance closure, which is essential to ensure the full understanding of degradation pathways.
Transaction costs and tradable mobility credits

Abstract Artificial markets for mobility credits have been proposed as an alternative to conventional congestion pricing schemes. This paper examines the effects of transaction costs on two types of markets: an auction market and a negotiated market. In an auction market, users purchase all of the needed mobility credits through a competitive bidding process. In a negotiated market, the users initially receive certain amount of mobility credits from the government and trade with each other through negotiation to fulfill their needs. We assume that a brokerage service is built in both markets to facilitate transactions and accordingly, the users have to pay a commission fee proportional to the value of trade. The users are also given the option to purchase credits from the government if for some reasons they cannot use or wish to avoid the markets. Our analyses suggest that the auction market can achieve the desired equilibrium allocation of mobility credits as long as the government sets its price properly and the unit transaction cost is lower than the price that the market would reach in absence of transaction costs. However, in the negotiated market, transaction costs could divert the system from the desired equilibrium regardless of their magnitude. More importantly, the initial allocation of mobility credits may affect the final equilibrium even when marginal transaction costs are constant.
Dynamic Equivalence of Control Systems via Infinite Prolongations

In this paper, we put the issue of dynamic equivalence of control systems in the context of pullbacks of coframings on infinite jet bundles over the state manifolds. While much attention has been given to differentially flat systems, i.e. systems dynamically equivalent to linear control systems, the advantage of this approach is that it allowed us to consider control affine systems as well. Through this context we are able to classify all control affine systems of three states and two controls under dynamic equivalence of the type (x,u) |-> y(x,u).
On the mass of M31

Recent work by several groups has established the properties of the dwarf satellites to M31. We reexamine the reported kinematics of this group employing a fresh technique we have developed previously. By calculating the distribution of a χ statistic (which we define in the paper) for the M31 system, we conclude that the total mass (disc plus halo) of the primary is unlikely to be as great as that of our own Milky Way. In fact the χ distribution for M31 indicates that, like NGC 3992, it does not have a massive halo. In contrast, the analysis of the satellites of NGC 1961 and NGC 5084 provides strong evidence for massive haloes surrounding both spiral galaxies.
Experience with the Hubble Space Telescope: 20 years of an archetype

The Hubble Space Telescope's mission is summarized, with special emphasis placed on the Space Telescope Science Institute's unique experience with Hubble's behavior as an astronomical telescope in the environment of low earth orbit for over two decades. Historical context and background are given, and the project's early scientific expectations are described. A general overview of the spacecraft is followed by a more detailed look at the optical design, both as intended and as built. Basic characteristics of the complete complement of science instruments are also summarized. Experience with the telescope on-orbit is reviewed, starting with the major initial problems, solutions, human servicing missions, and the associated expansion of the observatory's capabilities over this time. Specific attention is then given to understanding Hubble's optical quality and pointing/jitter performance, two fundamental characteristics of a telescope. Experience with-and the important mitigation of-radiation damage and contamination is also related. Beyond the telescope itself, the advances in data reduction, calibration, and observing techniques are briefly discussed, as well as the subsequent emergence of highly accessible high-level archival science products. Hubble's scientific impact concludes the discussion.
Contracting with Third Parties

assume that third parties are not available. Given this assumption, the equi librium outcome is not first-best efficient if contracts can be renegotiated. To be more specific, suppose an architect and a builder must cooperate to build a build ing. The quality of the building will depend on three things: the quality of the architect's design, the builder's skill, and a stochastic shock. We will refer to these three variables as the state of the world. The architect and the builder know the true state but no one else does. Thus, the state is "observable but not verifiable." (An outsider may be able to judge the quality of the building after it is built, but he cannot disentangle the various contributions to it.) Suppose the contract specifies ex post transfers as a function of announcements made by the architect and the builder (a "message game"). If both report the state truthfully, the transfers will reflect the contributions of each party and provide correct incentives to invest in the transac tion. In order to support an equilibrium where both tell the truth, however, it may be
8D display: a relightable glasses-free 3D display

magine a display that behaves like a window. Glancing through it, viewers perceive a virtual 3D scene with correct parallax, without the need to wear glasses or track the user. Light that passes through the display correctly illuminates the virtual scene. While researchers have considered such displays, or prototyped subsets of these capabilities, we contribute a new, interactive, relightable, glasses-free 3D display. By simultaneously capturing a 4D light field, and displaying a 4D light field, we are able to realistically modulate the incident light on rendered content. We present our optical design, and GPU pipeline. Beyond mimicking the physical appearance of objects under natural lighting, an 8D display can create arbitrary directional illumination patterns and record their interaction with physical objects. Our hardware points the way towards novel 3D interfaces, in which users interact with digital content using light widgets, physical objects, and gesture.
Hydrogen-mediated aldol reductive coupling of vinyl ketones catalyzed by rhodium: high syn-selectivity through the effect of tri-2-furylphosphine.

Catalytic hydrogenation of methyl vinyl ketone (MVK) and ethyl vinyl ketone (EVK) in the presence of diverse aldehydes at ambient temperature and pressure using tri-2-furylphosphine-ligated rhodium catalysts enables formation of aldol products with high levels of syn-diastereoselectivity. A progressive increase in diastereoselectivity is observed upon sequential replacement of phenyl residues for 2-furyl residues (Ph3P, FurPh2P, Fur2PhP, Fur3P). Hydrogen-labile functional groups, including alkynes, alkenes, benzylic ethers, and nitroarenes, remain intact under the coupling conditions.
Period computations for covers of elliptic curves

In this article, we construct algebraic equations for a curve C and a map f to an elliptic curve E, with pre-specified branching data. We do this by determining certain relations that the periods of C and E must satisfy and use these relations to approximate the coefficients to high precision. We then conjecture which algebraic numbers the coefficients are, and then we prove this conjecture to be correct.
Unsteady stator response to upstream rotor wakes

The results are presented of an investigation of the unsteady pressures generated on a stator due to its interaction with the wakes shed by an upstream rotor. The influence of stator solidity, incidence flow angle, and rotor-stator spacing are discussed. The results show a major influence due to stator solidity at large values of incidence angle where it is suspected that stall occurred. Comparisons of the measured data with an existing unsteady cascade analysis show similar trends in the chordwise variation of the predicted and measured unsteady pressure difference across the blades. Comparisons with an isolated airfoil analysis indicate the influence of solidity and unsteady blade-to-blade interaction. All comparisons were conducted for an incompressibl e flow with a reduced frequency of approximately 5.0. BPF c CN
Empirical modeling of the quiet time nightside magnetosphere

Empirical modeling of plasma pressure and magnetic field for the quiet time nightside magnetosphere is investigated. Two models are constructed for this study. One model, referred to here as T89R, is basically the magnetic field model of Tsyganenko (1989) but is modified by the addition of an inner eastward ring current at a radial distance of approximately 3 RE as suggested by observation. The other is a combination of the T89R model and the long version of the magnetic field model of Tsyganenko (1987) such that the former dominates the magnetic field in the inner magnetosphere while the latter prevails in the distant tail. The distribution of plasma pressure which is required to balance the magnetic force for each of these two field models is computed along the tail axis in the midnight meridian. The occurrence of pressure anisotropy in the inner magnetospheric region is also taken into account by determining an empirical fit to the observed plasma pressure anisotropy. This represents the first effort to obtain the plasma pressure distribution in force equilibrium with magnetic stresses from an empirical field model with the inclusion of pressure anisotropy. The inclusion of pressure anisotropy alters the plasma pressure by as much as a factor of approximately 3 in the inner magnetosphere. The deduced plasma pressure profile along the tail axis is found to be in good agreement with the observed quiet time plasma pressure for geocentric distances between approximately 2 and approximately 35 RE.
The Role of Fast Magnetosonic Waves in the Release and Conversion via Reconnection of Energy Stored by a Current Sheet

Using a simple two-dimensional, zero-? model, we explore the manner by which reconnection at a current sheet releases and dissipates free magnetic energy. We find that only a small fraction (3%-11% depending on current-sheet size) of the energy is stored close enough to the current sheet to be dissipated abruptly by the reconnection process. The remaining energy, stored in the larger-scale field, is converted to kinetic energy in a fast magnetosonic disturbance propagating away from the reconnection site, carrying the initial current and generating reconnection-associated flows (inflow and outflow). Some of this reflects from the lower boundary (the photosphere) and refracts back to the X-point reconnection site. Most of this inward wave energy is reflected back again and continues to bounce between X-point and photosphere until it is gradually dissipated, over many transits. This phase of the energy dissipation process is thus global and lasts far longer than the initial purely local phase. In the process, a significant fraction of the energy (25%-60%) remains as undissipated fast magnetosonic waves propagating away from the reconnection site, primarily upward. This flare-generated wave is initiated by unbalanced Lorentz forces in the reconnection-disrupted current sheet, rather than by dissipation-generated pressure, as some previous models have assumed. Depending on the orientation of the initial current sheet, the wave front is either a rarefaction, with backward-directed flow, or a compression, with forward-directed flow.
A Decomposition Theorem for Higher Rank Coxeter Groups

In this paper, we show that any Coxeter graph which defines a higher rank Coxeter group must have disjoint induced subgraphs each of which defines a hyperbolic or higher rank Coxeter group where the groups in question do not necessarily act cocompactly or cofinitely. We then use this result to demonstrate several classes of Coxeter graphs which define hyperbolic Coxeter groups and to produce structure theorems for hyperbolic Coxeter groups.
Extending the parking space

The action of the symmetric group S"n on the set Park"n of parking functions of size n has received a great deal of attention in algebraic combinatorics. We prove that the action of S"n on Park"n extends to an action of S"n"+"1. More precisely, we construct a graded S"n"+"1-module V"n such that the restriction of V"n to S"n is isomorphic to Park"n. We describe the S"n-Frobenius characters of the module V"n in all degrees and describe the S"n"+"1-Frobenius characters of V"n in extreme degrees. We give a bivariate generalization V"n^(^@?^,^m^) of our module V"n whose representation theory is governed by a bivariate generalization of Dyck paths. A Fuss generalization of our results is a special case of this bivariate generalization.
Tracking of Moving Fused Auditory Images by Children

Recent investigations (Cranford, Boose, & Moore, 1990a,b; Moore, Cranford, & Rahn, 1990) studied the ability of normal adult subjects to localize sounds under conditions that elicit the Precedence ...
Automated optical navigation with application to Galileo

This paper presents an overview of an automated optical navigation (AON) system, a lower-cost, faster, earth-based stepping stone to onboard systems. AON provides estimation (orbit determination) and maneuver subsystems which are automatically linked to provide the fast response required by the Galileo mission, AON's first user. A real-time interactive executive schedules the subsystems to run concurrently or sequentially and enables interactive computer-graphics displays designed to speed evaluation and certification of navigation solutions. A compact trajectory integrator provides a favorable combination of speed and accuracy. Resident on a low-cost minicomputer and coded primarily in HAL/S, the NASA standard language for flight software, AON approaches a prototype for autonomous onboard navigation systems of the future.
Higher elliptic genera

We show that elliptic classes introduced in \cite{annals} for spaces with infinite fundamental groups yield Novikov's type higher elliptic genera which are invariants of K-equivalence. This include, as a special case, the birational invariance of higher Todd classes studied recently by J.Rosenberg and J.Block-S.Weinberger. We also prove the modular properties of these genera, show that they satisfy a McKay correspondence, and consider their twist by discrete torsion.
Towards computationally sound symbolic analysis of key exchange protocols

We present a cryptographically sound formal method for proving correctness of key exchange protocols. Our main tool is a fragment of a symbolic protocol logic. We demonstrate that proofs of key agreement and key secrecy in this logic imply simulatability in Shoup's secure multi-party framework for key exchange. As part of the logic, we present cryptographically sound abstractions of CMA-secure digital signatures and a restricted form of Diffie-Hellman exponentiation, which is a technical result of independent interest. We illustrate our method by constructing a proof of security for a simple authenticated Diffie-Hellman protocol.
Freely suspended cellular "backpacks" lead to cell aggregate self-assembly.

Cellular “backpacks” are a new type of anisotropic, nanoscale thickness microparticle that may be attached to the surface of living cells creating a “bio-hybrid” material. Previous work has shown t...
Distinct Organization and Regulation of the Outer Kinetochore KMN Network Downstream of CENP-C and CENP-T

The kinetochore provides a vital connection between chromosomes and spindle microtubules [1, 2]. Defining the molecular architecture of the core kinetochore components is critical for understanding the mechanisms by which the kinetochore directs chromosome segregation. The KNL1/Mis12 complex/Ndc80 complex (KMN) network acts as the primary microtubule-binding interface at kinetochores [3] and provides a platform to recruit regulatory proteins [4]. Recent work found that the inner kinetochore components CENP-C and CENP-T act in parallel to recruit the KMN network to kinetochores [5-8]. However, due to the presence of these dual pathways, it has not been possible to distinguish differences in the nature of kinetochore assembly downstream of CENP-C or CENP-T. Here, we separated these pathways by targeting CENP-C and CENP-T independently to an ectopic chromosomal locus in human cells. Our work reveals that the organization of the KMN network components downstream of CENP-C and CENP-T is distinct. CENP-C recruits the Ndc80 complex through its interactions with KNL1 and the Mis12 complex. In contrast, CENP-T directly interacts with Ndc80, which in turn promotes KNL1/Mis12 complex recruitment through a separate region on CENP-T, resulting in functional relationships for KMN network localization that are inverted relative to the CENP-C pathway. We also find that distinct regulatory paradigms control the assembly of these pathways, with Aurora B kinase promoting KMN network recruitment to CENP-C and cyclin-dependent kinase (CDK) regulating KMN network recruitment to CENP-T. This work reveals unexpected complexity for the architecture and regulation of the core components of the kinetochore-microtubule interface.
Is it isomerization of cobalamins or simple hydrolysis of a propionamide side chain

Abstract Literature is replete with references to b-, d-, and e-monocarboxylic acids of cobalamin, supposedly resulting from hydrolysis of a propionamide side chain. Out work indicates that these species are not monocarboxylic acids but isomers of cobalamins. The ease of isomerization under mild conditions, its reversibility, the formation of intermediate(s), large interconversions between the new isomers, b-, d-, and e-B12′ and the observation using high resolution mass spectrometry that the molecular mass of protonated d-B12′ is identical to B12, all attest to genuine isomerization. Significant changes, in the puckering of the corrin ring, and in other parts of the molecule are clearly revealed by our earlier Mossbauer, proton and phosphorus nuclear magnetic resonance investigations, and as well as by the more recent carbon-13 and crystal structure studies reported in the literature.
IPO Research in Management and Entrepreneurship: Moving the Agenda Forward

Building on research from multiple fields, management and entrepreneurship scholars have shown increasing interest in the causes and consequences of initial public offerings (IPOs). The authors summarize this emerging literature and categorize research on IPOs into four broad themes: corporate governance, upper echelons, social influence, and innovation. They also review the various measures used by scholars to assess IPO performance. Based on this review, the authors develop an agenda for future research. This agenda provides both topics and research questions for future research and recommendations regarding IPO performance measurement.
Clinical utility of a colorimetric end-tidal CO2 detector in cardiopulmonary resuscitation and emergency intubation.

The purposes of this study were to evaluate the clinical utility of a colorimetric end-tidal CO2 (ETCO2) detector in confirming proper endotracheal intubation in patients requiring emergency intubation, to determine if this new device can be used as an adjunct to judge the effectiveness of cardiopulmonary resuscitation (CPR), and to determine whether the device can predict successful resuscitation from cardiopulmonary arrest. We studied prospectively 110 patients requiring emergency intubation for either respiratory distress (53 patients) or cardiopulmonary arrest (57 patients) by recording the color range of the indicator after the initial intubation. In patients who suffered a cardiopulmonary arrest, the color range was also recorded during CPR after the endotracheal tube was confirmed to be in the tracheal position and perfusion optimized, and at the moment CPR was stopped. The ETCO2 detector was 100% specific for correct endotracheal intubation in all patients. It was also highly sensitive (0.98) for correct endotracheal intubation in patients with respiratory distress. However, it was not sensitive (0.62) in patients with cardiopulmonary arrest and low perfusion. The sensitivity improved (0.88) when we used the ETCO2 range obtained after attempts to increase perfusion. A low ETCO2 color range in 19 patients undergoing CPR was interpreted as low cardiac output and prompted the physicians to attempt to increase perfusion. Of the patients who underwent CPR, no patient whose ETCO2 level remained less than 2% was successfully resuscitated. Those patients who had an ETCO2 level ≥2% had a significantly higher incidence of successful resuscitation. We conclude that the colorimetric ETCO2 detector is reliable and provides reassurance of correct endotracheal tube placement in patients requiring emergency intubation for respiratory distress. This device helps identify patients with low perfusion during CPR and is a useful prognostic indicator of successful short-term resuscitation.
Polymer–Fullerene Composite Solar Cells

Fossil fuel alternatives, such as solar energy, are moving to the forefront in a variety of research fields. Polymer-based organic photovoltaic systems hold the promise for a cost-effective, lightweight solar energy conversion platform, which could benefit from simple solution processing of the active layer. The function of such excitonic solar cells is based on photoinduced electron transfer from a donor to an acceptor. Fullerenes have become the ubiquitous acceptors because of their high electron affinity and ability to transport charge effectively. The most effective solar cells have been made from bicontinuous polymer–fullerene composites, or so-called bulk heterojunctions. The best solar cells currently achieve an efficiency of about 5 %, thus significant advances in the fundamental understanding of the complex interplay between the active layer morphology and electronic properties are required if this technology is to find viable application.
Dimension n Representations of the Braid Group on n Strings

Abstract In 1996, E. Formanek classified all the irreducible complex representations of Bn of dimension at most n − 1, where Bn is the Artin braid group on n strings. In this paper we extend this classification to the representations of dimension n, for n ≥ 9. We prove that all such representations are equivalent to the tensor product of a one-dimensional representation and a specialization of a certain one-parameter family of n-dimensional representations which was first discovered in 1996 by Tong, Yang, and Ma. In order to do this, we classify all the irreducible complex representations ρ of Bn for which rank(ρ(σi) − 1) = 2, where the σi are the standard generators.
Decentralized Control of Discrete Event Systems Using Prioritized Composition With Exclusion

A necessary and sufficient condition for decentralized control of discrete event systems via prioritized composition with exclusion (PCX) is provided. PCX was extended from prioritized synchronous composition (PSC) in order to model various Boolean modes of decision fusion by allowing the exclusivity of participation in system interactions . A notion of PCX-coobservability is introduced that captures the nature of PCX-based decision fusion, and a testing algorithm with polynomial complexity in the states of plant and specification is presented. The result is extended for multiple supervisors with multiple exclusivity sets based on an extended PCX definition.
Radiative Instabilities in Simulations of Spherically Symmetric Supernova Blast Waves

High-resolution simulations of the cooling regions of spherically symmetric supernova remnants demonstrate a strong radiative instability. This instability, whose presence is dependent on the shock velocity, causes large-amplitude fluctuations in the shock velocity. The fluctuations begin almost immediately after the radiative phase begins (upon shell formation) if the shock velocity lies in the unstable range; they last until the shock slows to speeds less than approximately 130 km s-1. We find that shock-velocity fluctuations from the reverberations of waves within the remnant are small compared to those that are due to the instability. Further, we find (in plane-parallel simulations) that advected inhomogeneities from the external medium do not interfere with the qualitative nature of the instability-driven fluctuations. Large-amplitude inhomogeneities may alter the phases of shock-velocity fluctuations but do not substantially reduce their amplitudes.
High-performance, high-capacity single-chip microcomputers

The MC6801 Single-Chip Microcomputer has long been recognized as a highperformance microcomputer. This paper provides a brief look at the complete M6801 family and then discusses the enhancements made to the Timer and Serial Communications Interface circuitry of the basic MC6801 to develop the new MC6801U4 microcomputer.The MC6801U4 strengthens the M6801 family position in the high-performance single-chip microcomputer marketplace.
Preparation of Vinyl Silyl Ethers and Disiloxanes via the Silyl-Heck Reaction of Silyl Ditriflates

Vinyl silyl ethers and disiloxanes can now be prepared from aryl-substituted alkenes and related substrates using a silyl-Heck reaction. The reaction employs a commercially available catalyst system and mild conditions. This work represents a highly practical means of accessing diverse classes of vinyl silyl ether substrates in an efficient and direct manner with complete regiomeric and geometric selectivity.
The Redox Chemistry of Manganese(III) and -(IV) Complexes

The oxidation-reduction thermodynamics for the manganese(III), -(IV), and -(II) ions, and their various complexes, are reviewed for both aqueous and aprotic media. In aqueous solutions the reduction potential for the manganese(III)/(II) couple has values that range from +1.51 V vs. NHE (hydrate at pH 0) to −0.95 V (glucarate complex at pH 13.5). The Mn(IV)/(III) couple has values that range from +1.0 V (solid MnIVO3 at pH 0) to −0.04 V (tris gluconate complex at pH 13.5). With anhydrous media the propensity for the Mn(III) ion to disproportionate to solid MnIVO2 and Mn(II) ion is avoided. For aprotic systems the range of redox potentials for various manganese complexes is from +2.01 V and +1.30 for the Mn(IV)/(III) and Mn(III)/(II) couples (bis terpyridyl tri-N-oxide complex in MeCN), respectively, to −0.96 V for the Mn(IV)/(III) couple (tris 3,5,-di-tert-butylcatecholate complex in Me2SO). The redox reactions between manganese complexes and dioxygen species (O2, O2, and H2O2) also are reviewed.
Nano-layered microneedles for transcutaneous delivery of polymer nanoparticles and plasmid DNA.

Current vaccine and therapeutic delivery is largely needle-based, [1] but a number of inherent risks and disadvantages to needle-based delivery have been recognized, such as the need for cold storage of liquid formulations, [1, 2] the requirement of trained personnel for administration, and reduced safety due to needle re-use and needle-based injuries. [3] To address these limitations, vaccination and therapeutics administration through the skin represents a promising alternative strategy, [4-6] and technologies promoting efficient transcutaneous delivery of a variety of drugs and vaccines has become a significant focus of recent research (reviewed in [7]). Recent work in this area has demonstrated the utility of microneedle arrays for efficient and pain-free disruption of the stratum corneum (SC), promoting transcutaneous delivery of a variety of bio-active materials. [8, 9] Microneedle delivery is often achieved by coating dried water-soluble drug formulations directly on the surfaces of solid microneedles. Parallel studies in the area of polyelectrolyte multilayer (PEM) engineering have demonstrated the potential for simple and versatile materials encapsulation into conformal thin films, providing robust control over materials release, solid-state stabilization of environmentally-sensitive encapsulated materials, and nanometer-scale control over film structure and composition. [10-16] We recently reported the construction of PEM films loaded with vaccine components prepared on flexible substrates for transcutaneous vaccine delivery. [10] However, these planar multilayer patches require prior SC disruption to permit entry of released cargos from the PEM films into the epidermis. We hypothesized that combining the flexible and highly tunable nature of PEM thin film coatings with microneedle substrates enabling direct entry of films into the viable epidermis could provide a versatile platform for single-step transcutaneous delivery of a broad range of drugs and drug carriers that is effective, generally applicable, inherently safe and pain-free, and potentially cost effective.
The transformational effects of technology on operations management

Over the years, advances in technology have transformed key aspects of operations management. New tools and technologies have been incorporated into the design and operation of service and production systems. Textbooks play an integral role in documenting the transformational effects of technology in specific fields. In this paper, the evolution of technology, its transformational effects, and influence on operations management is studied. Samples of the textbooks published within the last 35 years are searched and the results concluded.
PROTON-NEUTRON MASS DIFFERENCE

Incorporating the methods of the preceding paper we examine the electromagnetic contributions to the masses of the nucleons in terms of the graviton-nucleon vertex. Using the methods of sidewise dispersion relations, we consider this vertex as a function of the mass of one of the external nucleons, which enables us to express the contributions to $\ensuremath{\delta}M={M}_{p}\ensuremath{-}{M}_{n}$ in terms of integrals over scattering amplitudes. Applying the hypothesis of threshold dominance, we find that a simple explanation for the observed mass difference $\ensuremath{\delta}M=\ensuremath{-}1.3$ MeV emerges. In the low-energy region to which we restrict our attention, the only contributing states are the intermediate $N\ensuremath{\gamma}$ and $N\ensuremath{\pi}$ states. For the photon contributions we find the usual unsuccessful result $\ensuremath{\delta}{M}^{\ensuremath{\gamma}}\ensuremath{\sim}+0.5$ MeV as a consequence of the dominance of the Coulomb over the magnetic energy in the threshold region. However, in calculating the contribution of the nucleon mass shift back on itself from the $N\ensuremath{\pi}$ states of energy $W$, there is a term under the dispersion integral proportional to the difference of nucleon pole terms ${({W}^{2}\ensuremath{-}{M}_{n})}^{\ensuremath{-}1}\ensuremath{-}{({W}^{2}\ensuremath{-}{{M}_{p}}^{2})}^{\ensuremath{-}1}\ensuremath{\simeq}2M\ensuremath{\delta}M{({W}^{2}\ensuremath{-}{M}^{2})}^{\ensuremath{-}2}$, implying a large contribution due to the enhancement at threshold ${W}^{2}\ensuremath{\rightarrow}{M}^{2}$. Including this contribution we have $\ensuremath{\delta}M=+0.5 \mathrm{MeV}+1.3\ensuremath{\delta}M$ or $\ensuremath{\delta}M\ensuremath{\simeq}\ensuremath{-}1.7$ MeV, which suggests how the nucleon mass difference emerges in spite of the sign of the photon contribution.
Backward Uniqueness for the Heat Equation in Cones

It was shown in [4, 14] that a bounded solution of the heat equation in a half-space which becomes zero at some time must be identically zero, even though no assumptions are made on the boundary va...
Does endothelin-1 affect human spermatozoa function ?

PROBLEM: It has been reported that massive amounts of immunoreactive endothelins (ETS) exist in human seminal plasma. However, the physiological role of ETS in seminal plasma remains to be determined. We speculated that ETS might affect sperm function. METHOD: The present study was designed to investigate the effect of endothelium-1 (ET-1) on: (a) sperm motion parameters, (b) hyperactivated motility, (c) sperm-zona pellucida-binding capacity, (d) sperm-oocyte penetration capacity, (e) acrosome reaction and its prerequisite, an increase in intracellular Ca2+ concentration ([Ca2+]i), and to examine (f) the presence of binding sites for ET-1 in human sperm. Forty-six semen ejaculates from 14 fertile men were assessed under capacitating conditions after separation of the motile sperm fraction by wash and swim-up. RESULTS: ET-1 (1 (μm) exhibited significant stimulatory effects on sperm velocity at 30 min (P = 0.01), amplitude of lateral head displacement (ALH)max (P = 0.05), and ALHmean at 60 min (P = 0.04) in some samples (n = 10). However, these effects were not observed in experiments using a larger number of samples (n = 39). ET-1 had no effect on hyperactivated motility of sperm at 30 min to 24 h. Neither ET-3 nor IRL 1620, a selective ETB receptor agonist, affected sperm motion parameters or hyperactivated motility. ET-1 did not affect sperm-zona-binding capacity, sperm-oocyte penetration capacity, acrosome reaction, or [Ca2+]i of sperm. Specific binding sites for ET-1 were not detected on the cell surface of human sperm. CONCLUSIONS: Although ET-1 is present in massive amounts in human seminal plasma and may have the capacity to alter the quality of motile sperm in some samples, a physiological role of ET-1 in the modulation of the function of mature, ejaculated sperm still remains unknown.
Gas phase structures of the isomers of benzene, V. (dewar-benzene) by electron diffraction

Abstract The parent hydrocarbon, Dewar-benzene, has been studied by gas phase electron diffraction analysis. Assignment of C2v symmetry gave excellent agreement between the experimental and theoretical data. The structural parameters obtained were in good agreement with previous electron diffraction structures of substituted derivatives of the Dewar-benzene series. The structural parameters with error limits are (cf. Fig. 2): r(C3-C6) = 1.574 ± 0.005 A r(C2-C3) = 1.524 ± 0.002 A, r(C1-C2) = 1.345 ± 0.001 A, r(C3-C9) = 1.134 ± 0.004 A, r(C1-C7) = 1.124 ± 0.004 A, ∠C1C6C5 = 116.7 ± 0.6°, ∠C3C6C1 = 85.7 ± 0.2°, ∠C6C3C9 = 108.0 ± 3.0°, ∠C3C2C8 = 126.7 ± 2.5°, and α = 117.25 ± 0.6°. The angle γ was assumed to be 0°.
Harmonic splittings of surfaces

Abstract We give a harmonic maps proof of a theorem of Morgan-Otal and Skora, conjectured by Shalen: any minimal, small action of a higher-genus surface group on a real tree is dual to the lift of a measured foliation.
Covering minimum spanning trees of random subgraphs

We consider the problem of finding a sparse set of edges containing the minimum spanning tree (MST) of a random subgraph of G with high probability. The two random models that we consider are subgraphs induced by a random subset of vertices, each vertex included independently with probability p, and subgraphs generated as a random subset of edges, each edge with probability p.Let n denote the number of vertices, choose p ∈ (0, 1) possibly depending on n, and let b = 1/(1 - p). We show that in both random models, for any weighted graph G, there is a set of edges Q of cardinality O(n logbn) that contains the minimum spanning tree of a random subgraph of G with high probability. This result is asymptotically optimal. As a consequence, we also give a bound of O(kn) on the size of the union of all minimum spanning trees of G with some k vertices (or edges) removed. More generally, we show a bound of O(n logbn) on the size of a covering set in a matroid of rank n, which contains the minimum-weight basis of a random subset with high probability. Also, we give a randomized algorithm that calls an MST subroutine only a polylogarithmic number of times and finds the covering set with high probability. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2006
Modeling and Computer Simulation of a Microwave-to-DC Energy Conversion Element

A microwave-to-dc energv conversion element consisting of a dipole antenna, a low-pass filter, a Schottky-barrier diode, and a dc filter has been modeled using a distributed transmission-line modeling technique that includes skin-effect losses. Computer simulation has shown 80-percent conversion efficiency and has indicated that the diode generates significant power at higher harmonics due to a resonance effect.
Interpreting microarray expression data using text annotating the genes

Microarray expression data is being generated by the gigabyte all over the world with undoubted exponential increases to come. Annotated genomic data is also rapidly pouring into public databases. Our goal is to develop automated ways of combining these two sources of information to produce insight into the operation of cells under various conditions. Our approach is to use machine-learning techniques to identify characteristics of genes that are up-regulated or down-regulated in a particular micro-array experiment. We seek models that are (a) accurate. (b) easy to interpret, and (c) stable to small variations in the training data. This paper explores the effectiveness of two standard machine-learning algorithms for this task: Naive Bayes (based on probability) and PFOIL (based on building rules). Although we do not anticipate using our learned models to predict expression levels of genes, we cast the task in a predictive framework, and evaluate the quality of the models in terms of their predictive power on genes held out from the training. The paper reports on experiments using actual E. coli microarray data, discussing the strengths and weaknesses of the two algorithms and demonstrating the trade-offs between accuracy, comprehensibility, and stability.
The problem of the frontal lobe: A reinterpretation

The frontal lobe, despite decades of intensive research by physiologists, anatomists and clinicians, has remained the most mystifying of the major subdivisions of the cerebral cortex. Unlike any other of the great cerebral promontories, the frontal lobe appears not to contain a single sub-field that could be identified with any particular sensory modality, and its entire expanse must accordingly be considered association cortex. It should, perhaps, not be surprising in view of this circumstance alone that loss of frontal cortex, in primate forms in particular, leads to a complex functional deficit, the fundamental nature of which continues to elude laboratory investigators and clinicians alike. The purpose of this paper is, to review some aspects of this deficit in animals and man, and to inquire to what extent the consequences of frontal-lobe lesion can be evaluated in neurological terms.
LIFTS AND VERTEX PAIRS IN SOLVABLE GROUPS

Suppose G is a p -solvable group, where p is odd. We explore the connection between lifts of Brauer characters of G and certain local objects in G , called vertex pairs. We show that if χ is a lift, then the vertex pairs of χ form a single conjugacy class. We use this to prove a sufficient condition for a given pair to be a vertex pair of a lift and to study the behaviour of lifts with respect to normal subgroups.
Development of a general, enantioselective organocatalytic Mukaiyama–Michael reaction with α,β-unsaturated aldehydes

LUMO-lowering organocatalysis has been extended to promote the conjugate addition of S-alkyl and 1-pyrrolyl silylketene acetals to α,β-unsaturated aldehydes, yielding both, syn and anti Mukaiyama–Michael products with high levels of enantioselectivity. This strategy allows for the generation of chemically useful 1,5-dicarbonyl systems and again highlights the utility of organocatalysis.