cssi/SciSciGPT-SciSciNet huggingface dataset:
The Dependence of Galaxy Morphology and Structure on Environment and Stellar Mass

From the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5), we extract a sample of 4594 galaxies at redshifts 0.02 < z < 0.03, complete down to a stellar mass of M = 1010 M☉. We quantify their structure (Sersic index), morphology (Sersic index + "Bumpiness"), and local environment. We show that morphology and structure are intrinsically different galaxy properties, and we demonstrate that this is a physically relevant distinction by showing that these properties depend differently on galaxy mass and environment. Structure mainly depends on galaxy mass whereas morphology mainly depends on environment. This is driven by variations in star formation activity, as traced by color, which only weakly affects the structure of a galaxy but strongly affects its morphological appearance. The implication of our results is that the existence of the morphology-density relation is intrinsic and not just due to a combination of more fundamental, underlying relations. Our findings have consequences for high-redshift studies, which often use some measure of structure as a proxy for morphology. A direct comparison with local samples selected through visually classified morphologies may lead to biases in the inferred evolution of the morphological mix of the galaxy population, and misinterpretations in terms of how galaxy evolution depends on mass and environment.
From system F to typed assembly language

We motivate the design of typed assembly language (TAL) and present a type-preserving ttranslation from Systemn F to TAL. The typed assembly language we pressent is based on a conventional RISC assembly language, but its static type sytem provides support for enforcing high-level language abstratctions, such as closures, tuples, and user-defined abstract data types. The type system ensures that well-typed programs cannot violatet these abstractionsl In addition, the typing constructs admit many low-level compiler optimiztaions. Our translation to TAL is specified as a sequence of type-preserving transformations, including CPS and closure conversion phases; type-correct source programs are mapped to type-correct assembly language. A key contribution is an approach to polymorphic closure conversion that is considerably simpler than previous work. The compiler and typed assembly lanugage provide a fully automatic way to produce certified code, suitable for use in systems where unstrusted and potentially malicious code must be checked for safety before execution.
Nanoparticle surface charge mediates the cellular receptors used by protein-nanoparticle complexes.

Nanoparticles are increasingly important for biological applications ranging from drug delivery to cellular imaging. In the course of these applications, nanoparticles are exposed to a complex environment of extracellular proteins that can be adsorbed onto the surface of the nanoparticle, altering nanoparticle–cell interactions. We have investigated how proteins found in blood serum affect the binding of nanoparticles to the surface of cells. Using fluorescence microscopy, we find that the cellular binding of cationic nanoparticles is enhanced by the presence of serum proteins, while the binding of anionic nanoparticles is inhibited. We have determined that this difference in cellular binding is due to the use of distinct cellular receptors. Competition assays, quantified with flow cytometry, show that the protein–nanoparticle complex formed from the cationic nanoparticles binds to scavenger receptors on the cell surface. Interestingly, the protein–nanoparticle complex formed from anionic nanoparticles bi...
Advances in software engineering and their relations to pattern recognition and image processing

Abstract In recent years ‘software engineering’ has emerged as a discipline of programming. It includes the conceptualization, design, implementation, testing and modification of software systems. Related issues are languages, standards, distributed and parallel processing, and total programming environments. The fact that more than 80 percent of system development costs were in software rather than hardware helps one appreciate the importance of any effort to understand and enhance the software production process. Many pattern recognition projects involve fairly large software efforts. It makes sense not only for researchers to make use of the latest software tools and methologies but also to anticipate future changes.
Accretion Disk Models and Their X-Ray Reflection Signatures. I. Local Spectra

X-ray illumination of accretion disks is an invaluable diagnostic of the structure of these disks because of the associated iron Kα emission. Here we point out that the resulting reflected spectra depend very sensitively on the geometry of the X-ray source and that this fact can be efficiently used to test these models observationally. In particular, we discuss three different accretion disk geometries: the "lamppost model," accretion disks with magnetic flares, and the model with a full corona overlaying a cold thin disk. We show that in the case of the lamppost model, unless the X-ray luminosity of the central source is larger than that of the cold disk by a factor of 10 or more, a significant fraction of iron in the ionized skin of the disk is in the hydrogen and helium-like ions. Because these ions have large fluorescence yields, the resulting reflected spectra look strongly ionized, with equivalent width (EW) of the line increasing with X-ray luminosity LX up to the maximum of ~500 eV. This situation contrasts to the magnetic flare model, where the large X-ray flux near flares completely ionizes the skin of the disk and thus the resulting spectra appear to be that from a neutral material. The line EW in this model anticorrelates with X-ray luminosity and becomes arbitrarily small when LX is a good fraction of the Eddington luminosity. Finally, in the full corona case, due to the additional pressure and weight of the corona, the gas pressure (and its density) below the corona is always large enough to make the gas very cool and effectively neutral. No highly ionized skin forms in such a model. If the corona is Thomson thin, then EW of the line does not depend on the accretion disk or corona luminosities for the full corona model.
Atomistic deconstruction of current flow in graphene based hetero-junctions

We describe the numerical modeling of current flow in graphene heterojunctions, within the Keldysh Landauer Non-equilibrium Green's function (NEGF) formalism. By implementing a k-space approach along the transverse modes, coupled with partial matrix inversion using the Recursive Green's function Algorithm (RGFA), we can simulate on an atomistic scale current flow across devices approaching experimental dimensions. We use the numerical platform to deconstruct current flow in graphene, compare with experimental results on conductance, conductivity and quantum Hall, and deconstruct the physics of electron `optics' and pseudospintronics in graphene pn junctions. We also demonstrate how to impose exact open boundary conditions along the edges to minimize spurious edge reflections.
Radiation detectors: needs and prospects

Abstract Important applications for X- and γ-ray spectroscopy are found in prospecting, materials characterization, environmental monitoring, the life sciences, and nuclear physics. The specific requirements vary for each application with varying degrees of emphasis on either spectrometer resolution, detection efficiency, or both. Since no one spectrometer is ideally suited to this wide range of needs, compromises are usually required. Gas and scintillation spectrometers have reached a level of maturity, and recent interest has concentrated on semiconductor spectrometers. Germanium detectors are showing continuing refinement and are the spectrometers of choice for high resolution applications. The new high-Z semiconductors, such as CdTe and HgI2, have shown steady improvement but are limited in both resolution and size and will likely be used only in applications which require their unique properties.
A Collatz-type conjecture on the set of rational numbers

Abstract Let θ ( x ) = ( x − 1 ) / 3 if x ⩾ 1 , and θ ( x ) = 2 x / ( 1 − x ) if 0 ⩽ x 1 . We conjecture that the θ-orbit of every nonnegative rational number ends in 0. A weaker conjecture asserts that there are no positive rational fixed points for any map in the semigroup Λ generated by the maps 3 x + 1 and x / ( x + 2 ) . In this paper, we prove that the asymptotic density of the set of maps in Λ that have rational fixed points is zero. Moreover, we prove that certain types of elements in the semigroup Λ cannot have rational fixed points.
Automorphisms and Cohomology of Discrete Groups

Let G denote a discrete group of finite cohomological dimension. Calculating the cohomology of such groups is notoriously difficult, involving complicated geometric information attached to the group. For example, the cohomology of torsion-free arithmetic groups involves delicate questions about symmetric spaces and number theory. Perhaps the key difficulty lies in that there is no practical method for building up the Ž cohomology of G from that of its subgroups such as one can do for finite . groups . In this paper we outline a method for constructing non-trivial classes in U Ž . Ž . H G, F where F denotes a field with p elements based on the use of p p finite automorphism groups of G. Given an explicit presentation for G, Ž . Aut G can often be approached, and in particular its finite subgroups are sometimes accessible. Furthermore, it is an elementary observation that many interesting classes of groups admit numerous finite symmetries. An obvious but very important example is given by a normal torsion-free subgroup G in an arithmetic group U; any finite subgroup K : U will act on it via conjugation. Ž . Given G : Aut G , we can form the semidirect product G s G = G. w Let H : G denote a finite subgroup mapping onto G under the natural Ž . Ž . projection map. Then C H s C H l G : G and in the particular case G G Ž . < .4 when H s 1, x x g G , we have that
Effects of lamb rearing conditions on aggression and dominance relationships

Abstract The effects of rearing conditions on agonistic behavior were studied using lambs reared: (1) in a flock; (2) individually with a ewe; (3) with other lambs; (4) as individuals. The lambs were paired in a noncompetitive situation preweaning, and again postweaning, after 10 weeks of cohabitation in one group; competitive paired tests were also conducted postweaning. During the preweaning paired tests, the socially deprived lambs exhibited play and investigatory behavior while the flock reared lambs ignored the other lambs or were aggressive. Neither the postweaning noncompetitive nor the competitive paired tests revealed disparity in behavior among treatments.
Spallation Neutron Source and Other High Intensity Proton Sources

This lecture is an introduction to the design of a spallation neutron source and other high intensity proton sources. It discusses two different approaches: linac-based and synchrotron-based. The requirements and design concepts of each approach are presented. The advantages and disadvantages are compared. A brief review of existing machines and those under construction and proposed is also given. An R&D program is included in an appendix.
Programming with data frames for everyday data items

Processing everyday data items such as dollar amounts, time, dates, and account numbers constitutes a significant portion of real-world computer applications. Programmers involved with everyday data items confront the drudgery of writing routines to recognize, validate, transform, store, retrieve, manipulate, and display these items and also the challenge to develop user-friendly data-entry systems and insure data integrity. They usually meet these challenges using various and sundry ad hoc techniques.
On the Gabai-Eliashberg-Thurston Theorem

We present a new, completely three-dimensional proof of the fact, due to the combined work of Gabai and Eliashberg-Thurston, that every closed, oriented, connected, irreducible 3-manifold with nonzero second homology carries a universally tight contact structure.
Exploiting a transmission grating spectrometer

The availability of compact transmission grating spectrometers now allows an attractive and economical alternative to the more familiar Czerny–Turner configuration for many high-temperature plasma applications. Higher throughput is obtained with short focal length refractive optics and stigmatic imaging. Many more spectra can be obtained with a single spectrometer since smaller, more densely packed optical input fibers can be used. Multiple input slits, along with a bandpass filter, can be used to maximize the number of spectra per detector, providing further economy. Curved slits can correct for the strong image curvature of the short focal length optics. Presented here are the governing grating equations for both standard and high-dispersion transmission gratings, defining dispersion, image curvature, and desired slit curvature, that can be used in the design of improved plasma diagnostics.
The topology of quaternionic contact manifolds

We explore the consequences of curvature and torsion on the topology of quaternionic contact manifolds with integrable vertical distribution establishing a general Myers theorem for quaternionic contact manifolds of positive horizontal Ricci curvature. We introduce the category of almost Einstein quaternionic manifolds, characterized by the vanishing of one component of the torsion for the Biquard connection. Under the assumption of non-positive horizontal sectional curvatures, we show that the universal cover of any complete almost Einstein quaternionic contact manifold is either \(\mathbb {R}^{h+3}\) or \(\mathbb {R}^h \times \mathbb {S}^3\).
Relativistic quarkonia from anisotropic lattices

Abstract We report on new results for the spectrum of quarkonia using a fully relativistic approach on anisotropic lattices with quark masses in the range from strange to bottom. A fine temporal discretisation also enables us to resolve excitations high above the ground state. In particular we studied the mass dependence and scaling of hybrid states.
Former Audit Partners and Abnormal Accruals

Audit clients often employ a former partner of their present auditor as an officer or a director. This “revolving door” practice presents a potential threat to auditor independence. Using the Jones (1991) model to calculate abnormal accruals for firms in 1998 and 1999, we find that firms employing former partners as officers or directors report larger signed and unsigned abnormal accruals than other firms, after controlling for other factors that plausibly affect abnormal accruals. To ensure that the results are not driven by performance characteristics of the former partner firms, we construct a performance‐matched control sample and obtain consistent results. We also observe a disproportionately higher (lower) proportion of former partner firms than expected just meeting (missing) analysts' earnings forecasts.
Synthesis of fluorinated benzophenones, xanthones, acridones, and thioxanthones by iterative nucleophilic aromatic substitution.

Fluorination of fluorophores can substantially enhance their photostability and improve spectroscopic prop- erties. To facilitate access to fluorinated fluorophores, bis- (2,4,5-trifluorophenyl)methanone was synthesized by treatment of 2,4,5-trifluorobenzaldehyde with a Grignard reagent derived from 1-bromo-2,4,5-trifluorobenzene, followed by oxidation of the resulting benzyl alcohol. This hexafluorobenzophenone was subjected to sequential nucleophilic aromatic substitution reactions, first at one or both of the more reactive 4,4!-fluorines, and second by cyclization through substitution of the less reactive 2,2!-fluorines, using a variety of oxygen, nitrogen, and sulfur nucleophiles, including hydroxide, methoxide, amines, and sulfide. This method yields symmetrical and asymmetrical fluorinated benzophenones, xanthones, acridones, and thioxanthones and provides scalable access to known and novel precursors to fluorinated analogues of fluorescein, rhodamine, and other derivatives. Spectroscopic studies revealed that several of these precursors are highly fluorescent, with tunable absorption and emission spectra, depending on the substituents. This approach should allow access to a wide variety of novel fluorinated fluorophores and related compounds.
The Ginibre Ensemble of Real Random Matrices and its Scaling Limits

We give a closed form for the correlation functions of ensembles of a class of asymmetric real matrices in terms of the Pfaffian of an antisymmetric matrix formed from a 2 × 2 matrix kernel associated to the ensemble. We apply this result to the real Ginibre ensemble and compute the bulk and edge scaling limits of its correlation functions as the size of the matrices becomes large.
A hierarchical version of the de Finetti and Aldous-Hoover representations

We consider random arrays indexed by the leaves of an infinitary rooted tree of finite depth, with the distribution invariant under the rearrangements that preserve the tree structure. We call such arrays hierarchically exchangeable and prove that they satisfy an analogue of de Finetti’s theorem. We also prove a more general result for arrays indexed by several trees, which includes a hierarchical version of the Aldous-Hoover representation.
Kinetics of fluorine, chlorine and hydroxyl exchange in fluorapatite

Abstract A series of experiments were performed to obtain diffusion coefficients for the exchange of fluorine, chlorine and hydroxyl in natural fluorapatite at both 1 atm and 1 GPa. Gradients in chemical potential were generated in 1-atm experiments by juxtaposing powdered chlorapatite and the natural face (flux ∥ to a -axis) or a polished basal section (flux ∥ to c -axis) of gem-quality fluorapatite single crystals. Compositional contrast was generated in hydrothermal experiments at 1 GPa by encapsulating a fluorapatite crystal + H 2 O ± a crimped, but unwelded, inner capsule containing chlorapatite. Both configurations produced compositional profiles in fluorapatite arising from the loss of fluorine and the uptake or loss of chlorine ± hydroxyl. Electron microprobe and FT-IR analytical traverses were used to obtain composition vs. distance data in the fluorapatite and Boltzmann-Matano analysis and error-function inversion were used to calculate diffusion coefficients. In accordance with the requirement of charge neutrality, diffusion coefficients calculated using either chlorine or fluorine concentration profiles were found to be essentially identical and profiles for hydroxyl are in qualitative agreement with the latter D -values. Diffusion coefficients from 1-atm experiments showed a positive correlation with chlorine concentration, whereas values from experiments at 1 GPa exhibited no such variation. In 1-atm experiments, a decrease in the diffusion coefficient could be correlated with a drop in the bulk OH content of apatite as measured in the cores of runproducts. Diffusion coefficients measured in 1-GPa experiments showed no such variability and the OH contents of apatites, as well as measured diffusivities, were uniformly higher. Diffusion coefficients determined in 1-GPa experiments of different duration yielded similar values as did those measured in 1-atm experiments in which the bulk OH content of runproducts were the same. Diffusion coefficients measured in this study define the following Arrhenius relations: D(1 atm , ∥ c)=1.6·10 −4 ( +2.2·10 −3 −1.1·10 −5 ) m 2 s −1 exp −284±30 kJ mol −1 RT D(1 atm , ∥ a)=1.3·10 −9 m 2 s −1 exp −216 kJ mol −1 RT D(1 GPa , ∥ c=8.1·10 −8 ( +4.2·10 −7 −1.6·10 −8 ) m 2 s −1 exp −173±17 kJ mol −1 RT Results of this study indicate that, arising from changes in P , T or fluid/melt chemistry, apatite may rapidly develop measurable F-Cl-OH zoning profiles via diffusion ∥ to c with little or no gradients expected ∥ to the a -axis. Characterization of compositional gradients in apatite sections along the c -axis may therefore offer the best means of utilizing apatite to evaluate the most recent changes in the halogen chemistry of coexisting fluids or magmas. In addition, calculations using the diffusion data from this study suggest that only under conditions of rapid cooling, low initial temperatures or chemical isolation, will the halogen chemistry of apatite remain pristine. Caution is therefore suggested when interpreting apatite halogen chemistry unless other evidence for halogen retention are available.
Stock Splits, Broker Promotion, and Decimalization

Stock split ex-dates are associated with both an increased intensity of small investor buying and a positive abnormal return. The broker promotion hypothesis suggests that the increase in relative spread after a split induces brokers to promote splitting stocks to small investors. The trading inconvenience hypothesis ascribes the ex-split effects to inconveniences such as investors' aversion to dealing with due bills, which is unrelated to relative spreads. The reduction in the bid-ask spread due to decimalization allows us to disentangle these two hypotheses. During the 1/8th pricing period, we show that after the ex-date, the relative spread increases significantly. The average buy order size decreases and the frequency of small transactions increases after the split. After decimalization, these changes are smaller in magnitude. We observe significant positive abnormal returns around the ex-date during the 1/8th pricing period, but not in the decimal pricing period. These results support the broker promotion hypothesis.
Dueling Stakeholders and Dual-Hatted Systems Engineers: Engineering Challenges, Capabilities, and Skills in Government Infrastructure Technology Projects

Systems engineering projects that support government enterprises face substantial challenges due to demands from diverse stakeholders and rapidly changing technologies. In this paper, we present findings from the analysis of five case studies of systems engineering projects for large government enterprises. We focus on what can be learned from systems engineers, their essential role, and their engineering practices. As they work to establish interoperability across preexisting and new technologies, thereby evolving an infrastructure, the engineers commonly face “agonistic” tensions between groups of stakeholders. Temporal pacing conflicts are especially prevalent, such as those between some stakeholder groups concerned with fast-paced streams of innovation and others concerned with current operations. In response, many engineers are following an evolutionary approach, developing new capabilities for incremental modularization and re/integration of technologies and associated practices across organizational (stakeholder) boundaries. Additionally, engineers are leveraging their professional role and developing new skills of influence to support these capabilities for addressing stakeholder tensions. We close by discussing implications of our findings for the management of infrastructure technology projects, for organizational design and engineering of government enterprises, and for the changing role of systems engineers.
Moment feature variability in uncertain propagation channels

In this study, moments of a signal as features for classification in active sonar systems are considered. The authors analyse the impact of propagation effects on the moment features, including the effect of random variability in certain channel parameters, such as target distance. Since the propagation model includes frequency-dependent effects that induce non-stationarities in the propagating signal, the authors use a time-frequency based approximation technique to analyse the moments. The results show how particular random channel effects increase the variability in the moment features, and thus provide some insight on the possible degradation in classification performance of the moment features.
Bow Shock and magnetosheath waves at Mercury

Mariner 10 measurements at the Mercury bow shock provide examples where the magnetic field is approximately parallel or perpendicular to the bow shock normal. Upstream of a broad irregular parallel shock, left hand circularly polarized waves are observed which cut off very sharply at approximately 4 Hz. Upstream of a perpendicular shock, right hand circularly polarized waves are observed which persist up to the Nyquist frequency of 12 Ha. Determination of the wave propagation vector as a function of frequency helps conclusively identify the waves as whistler mode waves propagating from the shock. The magnetosheath downstream of the parallel shock is disturbed more than that downstream of the perpendicular shock particularly below 1 Hz. In the latter case regular left hand polarized waves observed slightly above the proton gyrofrequency are identified as ion cyclotron waves with wavelength approximately 300 km which are Doppler shifted up to their observed frequency.
The effects of patient characteristics on ADHD diagnosis and treatment: a factorial study of family physicians

Attention Deficit Hyperactivity Disorder (ADHD) is a costly and prevalent disorder in the U.S., especially among youth. However, significant disparities in diagnosis and treatment appear to be predicted by the race and insurance status of patients. This study employed a web-based factorial survey with four ADHD cases derived from an ADHD clinic, two diagnosed with ADHD in actual evaluation, and two not. Randomized measures included race and insurance status of the patients. Participants N = (187) included clinician members of regional and national practice-based research networks and the U.S. clinical membership of the Society of Teachers of Family Medicine. The main outcomes were decisions to 1) diagnose and 2) treat the cases, based upon the information presented, analyzed via binary logistic regression of the randomized factors and case indicators on diagnosis and treatment. ADHD-positive cases were 8 times more likely to be diagnosed and 12 times more likely to be treated, and the male ADHD positive case was more likely to be diagnosed and treated than the female ADHD positive case. Uninsured cases were significantly more likely to be treated overall, but male cases that were uninsured were about half as likely to be diagnosed and treated with ADHD. Additionally, African-American race appears to increase the likelihood of medicinal treatment for ADHD and being both African-American and uninsured appears to cut the odds of medicinal treatment in half, but not significantly. Family physicians were competent at discerning between near-threshold ADHD-negative and ADHD positive cases. However, insurance status and race, as well as gender, appear to affect the likelihood of diagnosis and treatment for ADHD in Family Medicine settings.
Direct observations of hydrogen enhanced crack propagation in iron

Investigation of hydrogen enhanced fracture of iron and steel has given rise to numerous theoretical explanations for the observed phenomena. Despite this effort, the basic parameters of the explanation, whether H affects the ''''cohesive energy'' of the solid, whether it affects the surface energy, whether it influences the plastic processes at the crack tip or some combination of these have not yet been clearly established. The paper presents the first direct observations of hydrogen related fracture using in situ fracture studies in H/sub 2/ gas in the environmental cell of a H.V.E.M.
Dynamic Kinetic Resolution via Dual-Function Catalysis of Modified Cinchona Alkaloids: Asymmetric Synthesis of α-Hydroxy Carboxylic Acids

A highly enantioselective catalytic transformation of racemic alpha-hydroxy acids to optically active alpha-hydroxy acids is reported. A new procedure was developed for the condensation of racemic alpha-hydroxy acids with trichloromethyl chloroformate (diphosgene) at room temperature in the presence of activated charcoal to form 5-substituted-1,3-dioxolane-2,4-diones in 90-100% yield. An efficient dynamic kinetic resolution of 5-aryl dioxolanediones was realized via a modified cinchona alkaloid-catalyzed alcoholytic opening of the dioxolanedione ring, generating a variety of optically active alpha-hydroxy esters in 91-96% ee and 61-85% chemical yield. In this dynamic kinetic resolution, the modified cinchona alkaloid was found to serve dual catalytic roles, mediating both the rapid racemization of the 5-aryl dioxolanediones and the enantioselective alcoholytic ring opening of the 5-aryl dioxolanediones. Consequently, both enantiomers of the 5-aryl dioxolanediones were converted to highly enantiomerically enriched aromatic alpha-hydroxy esters in yields (61-85%), far exceeding the maximum of 50% for a normal kinetic resolution. This development not only represents an expansion of the scope of asymmetric acyl-transfer catalysis of synthetic catalysts but also provides a new approach for the development of efficient chemical dynamic kinetic resolutions promoted by a single catalyst. 5-Alkyl dioxolanediones were resolved by a conventional but highly enantioselective kinetic resolution to provide alpha-hydroxy acids and esters in high optical purity and good yields.
Atomic-Scale Friction Measurements Using Friction Force Microscopy. Part 1. General Principles and New Measurement Techniques

Abstract : Friction force measurements using modified atomic force microscopy, called here Friction Force Microscopy (FFM), are becoming increasingly important in the understanding of fundamental mechanisms of friction, wear, and lubrication, and to study interfacial phenomena in micro- and nanostructures used in magnetic storage systems and Microelectromechanical Systems (MEMS). FFMs can be used to study engineering surfaces in dry or wet conditions. A review of existing designs of FFMs and methods of friction force measurements is presented. In terms of friction force measurements, there are important issues related to the basic operation and calibration of these instruments which have not been fully studied. A new method of measuring friction fore using a commercial FFM and a calibration Procedure for conversion of measured data to normal and friction forces are presented. Microscale friction data of selected materials are presented and discussed in light of macrofriction measurements.
Targeting tumor cell motility as a strategy against invasion and metastasis

Advances in diagnosis and treatment have rendered most solid tumors largely curable if they are diagnosed and treated before dissemination. However, once they spread beyond the initial primary location, these cancers are usually highly morbid, if not fatal. Thus, current efforts focus on both limiting initial dissemination and preventing secondary spread. There are two modes of tumor dissemination – invasion and metastasis – each leading to unique therapeutic challenges and likely to be driven by distinct mechanisms. However, these two forms of dissemination utilize some common strategies to accomplish movement from the primary tumor, establishment in an ectopic site, and survival therein. The adaptive behaviors of motile cancer cells provide an opening for therapeutic approaches if we understand the molecular, cellular, and tissue biology that underlie them. Herein, we review the signaling cascades and organ reactions that lead to dissemination, as these are non-genetic in nature, focusing on cell migration as the key to tumor progression. In this context, the cellular phenotype will also be discussed because the modes of migration are dictated by quantitative and physical aspects of the cell motility machinery.
Plausible clocks: constant size logical clocks for distributed systems

In a Distributed System with N sites, the precise detection of causal relationships between events can only be done with vector clocks of size N. This gives rise to scalability and efficiency problems for logical clocks that can be used to order events accurately. In this paper we propose a class of logical clocks called plausible clocks that can be implemented with a number of components not affected by the size of the system and yet they provide good ordering accuracy. We develop rules to combine plausible clocks to produce more accurate clocks. Several examples of plausible clocks and their combination are presented. Using a simulation model, we evaluate the performance of these clocks. We also present examples of applications where constant size clocks can be used.
Palladium-Catalyzed Decarboxylative sp3−sp3 Coupling of Nitrobenzene Acetic Esters

Allylic esters of nitrobenzene acetic acids undergo facile palladium-catalyzed decarboxylative coupling. Both mono- and dinitroarene substrates give high yields of the coupled products. Moreover, the rates of the reactions suggest that decarboxylation is rate-limiting and substrates that sterically disfavor attainment of the reactive conformation for decarboxylation are not viable. Finally, reduction of the product nitroarenes to the corresponding anilines provides access to a variety of heterocycles including quinolines and dihydroquinolones.
The isolation of undistorted sinusoids in real time

A single-input, multiple-output adaptive filter that takes a multisinusoidal input signal and produces the individual sinusoids at each of the outputs is described. The individual outputs have identical amplitudes and phases to the components of the original input signal. The filter can be adapted in real time using approximate Gauss-Newton updates without requiring any matrix operations or divisions. The filter is an extension of a cascade adaptive IIR (infinite impulse response) notch filter reported previously. The filter is very amenable to being realized using custom ICs or DSP (digital signal processing) ICs, as no divisions are required and most of the filter is composed of identical biquads (which are very insensitive to the errors caused by finite accuracy in fixed-point implementations). The structure is especially good at isolating small-amplitude sinusoids when in the proximity of much larger sinusoids of unknown frequencies. >
Motion Interpolation With G2 Composite Bézier Motions

This paper deals with smooth motion interpolation. It presents two geometric algorithms for synthesizing composite Bezier motions with second-order geometric continuity (G 2 ). The first one is a direct algorithm for constructing a G 2 spline motion that approximates a set ofdisplacements ; the second one is an inverse design algorithm for a G 2 spline motion that interpolates through a set of displacements. The results are useful for computer aided motion animation, and Cartesian trajectory generation for CNC machines and robot manipulators.
Copper mediated reactions in nucleoside synthesis

Abstract The regiospecific functionalization of the base moiety of purine nucleosides through copper-mediated nucleophilic reactions is described.
Social Criticism, Existentialism, and Tremendismo In Cela's La Familia De Pascual Duarte

(1966). Social Criticism, Existentialism, and Tremendismo In Cela's La Familia De Pascual Duarte. Kentucky Foreign Language Quarterly: Vol. 13, No. sup1, pp. 25-33.
Extending temporal logic to support high-level simulations

A high-level simulation language based on temporal logic is described. The language combines a large set of temporal tenses and a rich class of high-level modeling primitives. Also an implementation of the language interpreter is presented. Finally, a real-world case study is described that shows how a programmer can develop structured, reliable, and well-maintainable simulation programs using the language.
Synthesis of nitrogen heterocycles via palladium-catalyzed intramolecular cyclization

Abstract Catalytic amounts of Pd(OAc)2 in the presence of n -Bu4NCl, DMF and an appropriate base (Na2CO3, (NaOAc or Et3N) cyclize nitrogen-containing o -iodoaryl alkenes to indoles, indolines,3 oxindoles, quinolines, isoquinolines and isoquinolones in short reaction times, under mild temperatures, and in high yields.
Silver-Mediated Fluorination of Functionalized Aryl Stannanes

We report a regiospecific silver-mediated fluorination of aryl stannanes. The presented reaction can afford complex fluoroarenes from readily available phenols in three steps. The operational simplicity and the broad substrate scope of the fluorination should render this reaction a useful tool for the synthesis of milligram to gram quantities of functionalized aryl fluorides. Silver-mediated oxidative transformations of aryl nucleophiles that proceed via bimetallic redox processes are a new avenue to develop carbon-heteroatom bond formations.
Bioactive heterocyclic analogs of the antitumor drug, podophyllotoxin

3,4-Methylenedioxyphenol (sesamol) condenses with pyrrolidine and aromatic aldehydes to yield Mannich bases of type 4. The Mannich bases react readily with ketonic reagents to form pyrrolidinylbenzopyran derivatives which provide a simple route to antimitotic and bioactive heterocyclic analogs of the anti-cancer drug, podophyllotoxin.
The effect of public opinion on social policy generosity

Social scientists have explored the determinants of social policy generosity fairly extensively. But relatively few empirical studies, and virtually no comparative analyses, have assessed the influence of public opinion. There is reason to hypothesize such an effect in democratic countries, as policy makers are likely to respond, at least to some extent, to the policy preferences of the citizenry (Page and Shapiro, 1983; Shapiro and Young, 1989; Burstein, 1998). In a recent article and book, Brooks and Manza (2006, 2007) examine the impact of public support for social policy on social policy generosity. Brooks and Manza conclude that ‘mass policy preferences exert a significant influence over welfare state spending’ in affluent democratic countries (2006, p. 490). They reach this conclusion based on analysis of 43 observations of social policy preferences and social expenditures in 15 countries from the mid-1980s through the end of the 1990s. I suspect public opinion about social policy does indeed have some impact on social policy program details and expenditures. But as I suggest in this research note, I do not think this can be inferred from Brooks and Manza’s evidence.
Bioisosterism: A Rational Approach in Drug Design.

Years of cumulative research can result in the development of a clinically useful drug, providing either a cure for a particular disease or symptomatic relief from a physiological disorder. A lead compound with a desired pharmacological activity may have associated with it undesirable side effects, characteristics that limit its bioavailability, or structural features which adversely influence its metabolism and excretion from the body. Bioisosterism represents one approach used by the medicinal chemist for the rational modification of lead compounds into safer and more clinically effective agents. The concept of bioisosterism is often considered to be qualitative and intuitive.1 The prevalence of the use of bioisosteric replacements in drug design need not be emphasized. This topic has been reviewed in previous years.2-5 The objective of this review is to provide an overview of bioisosteres that incorporates sufficient detail to enable the reader to understand the concepts being delineated. While a few popular examples of the successful use of bioisosteres have been included, the George Patani graduated with a B.Pharm. in 1992 from the College of Pharmaceutical Sciences, Mangalore University at Manipal, India. In 1996, he received his M.S. in Pharmaceutical Science at Rutgers University under the direction of Professor Edmond J. LaVoie. He is presently pursuing graduate studies in pharmaceutics. His current research interests are focused on drug design and controlled drug delivery.
An Astrometric Companion to the Nearby Metal-Poor, Low-Mass Star LHS 1589* **

We report the discovery of a companion to the high proper motion star LHS 1589, a nearby high-velocity, low-mass subdwarf. The companion (LHS 1589B) is located 0.224'' ± 0.004'' to the southwest of the primary (LHS 1589A), and is 0.5 mag fainter than the primary in the Ks band. The pair was resolved with the IRCAL infrared camera at Lick Observatory, operating with the Laser Guide Star Adaptive Optics system. A low-resolution spectrum of the unresolved pair obtained at the MDM observatory shows the source to be consistent with a cool subdwarf of spectral subtype sdK7.5. A photometric distance estimate places the metal-poor system at a distance d = 81 ± 18 pc from the Sun. We also measure a radial velocity Vrad = 67 ± 8 km s-1, which, together with the proper motion and estimated distance, suggests that the pair is roaming the inner Galactic halo on a highly eccentric orbit. With a projected orbital separation s = 18.1 ± 4.8 AU, and a crude estimate of the system's total mass, we estimate the orbital period of the system to be in the range 75 yr < P < 500 yr. This suggests that the dynamical mass of the system could be derived astrometrically, after monitoring the orbital motion over a decade or so. The LHS 1589AB system could thus provide a much needed constraint to the mass-luminosity relationship of metal-poor, low-mass stars.
Performance of the LBL ECR ion source

Abstract The LBL Electron Cyclotron Resonance (ECR) ion source in test operation since January 1984 has produced a wide variety of high charge state ion beams suitable for injection into the 88-inch Cyclotron. Two recent developments have dramatically improved the capability of the ECR source. The first development was the production of metallic ions. The intensities of aluminum ions produced were 36, 22, 10, and 0.065 eμA for charge states 6, 7, 8, and 11, respectively. Calcium ion intensities were 36, 31, 4.6, and 0.20 eμA for charge states 8, 9, 12, and 14, respectively. The second development was the replacement of the sextupole magnet used in all other high charge state ECR sources with an octupole structure. This modification resulted in a dramatic improvement in the intensities of the high charge state beams and a significant upward shift in the charge state distribution (CSD). The ECR-octupole or “OCTIGUN” has produced 89, 52, 9, and 2.5 eμA. of Ar8,9,11,12+ and 21, 10, and 0.34 eμA of Kr10,14,18+, respectively. For the high charge states of argon and krypton the improvement gained by using the octupole is typically a factor of 5 to 10.
Emission from ferroelectric cathodes

We have recently initiated an investigation of electron emission from ferroelectric cathodes. Our experimental apparatus consisted of an electron diode and a 250 kV, 12 Ω, 70 ns pulsed high voltage power source. A planar triode modulator driven by a synthesized waveform generator initiates the polarization inversion and allows inversion pulse tailoring. The pulsed high voltage power source is capable of delivering two high voltage pulses within 50 μs of each other and is capable of operating at a sustained repetition rate of 5 Hz. Our initial measurements indicate that emission current densities above the Child-Langmuir space charge limit, JCL, are possible. We explain this effect to be based on a non-zero initial energy of the emitted electrons. We also determined that this effect is strongly coupled to relative timing between the inversion pulse and application of the main anode-cathode pulse. We also have initiated brightness measurements of the emitted beam and estimate a preliminary lower bound to be on the order of 109 A/m2rad2. As in our previous measurements at this Laboratory, we performed the measurement using a pepper pot technique. Beamlet profiles are recorded with a fast phosphor and gated cameras. We describe our apparatus and preliminary measurements.
Electrophilic Aromatic Substitution Reactions of 1,2-Dihydro-1,2-azaborines

The aromatic boron−nitrogen heterocycle 1,2-dihydro-1,2-azaborine undergoes classical electrophilic substitution. These reactions allow easy functionalization to provide a variety of 3- and 5-substituted derivatives.
Ultrafilters and Partial Products of Infinite Cyclic Groups

ABSTRACT We consider, for infinite cardinals κ and α ≤ κ+, the group ∏(κ, < α) of sequences of integers, of length κ, with nonzero entries in fewer than α positions. Our main result tells when ∏(κ, < α) can be embedded in ∏(λ, < β). The proof involves some set-theoretic results, one about families of finite sets and one about families of ultrafilters.
Determining the Absolute Astrometric Error in Chandra Source Catalog Positions

Although relative errors can readily be calculated, the absolute astrometric accuracy of the source positions in the Chandra Source Catalog (CSC), version 1.0, is a priori unknown. However, the cross-match with stellar objects from the Sloan Digital Sky Survey offers the opportunity to compare the apparent separations of the cross-matched pairs with the formally calculated errors. The analysis of these data allowed us to derive a value of 016 for the residual absolute astrometric error in CSC positions. This error will be added to the published position errors in the CSC from now on, starting with CSC, version 1.1.
A streamlined method for chiral fermions on the lattice

We discussed the use of renormalization counterterms to restore the chiral gauge symmetry in a lattice theory of Wilson fermions. We show that a large class of counterterms can be implemented automatically by making a simple modification to the fermion determinant.
Numerical Schubert Calculus

We develop numerical homotopy algorithms for solving systems of polynomial equations arising from the classical Schubert calculus. These homotopies are optimal in that generically no paths diverge. For problems defined by hypersurface Schubert conditions we give two algorithms based on extrinsic deformations of the Grassmannian: one is derived from a Grobner basis for the Plucker ideal of the Grassmannian and the other from a SAGBI basis for its projective coordinate ring. The more general case of special Schubert conditions is solved by delicate intrinsic deformations, called Pieri homotopies, which first arose in the study of enumerative geometry over the real numbers. Computational results are presented and applications to control theory are discussed.
Origin, development, and differentiation of cardiac fibroblasts

Abstract Cardiac fibroblasts are the most abundant cell in the mammalian heart. While they have been historically underappreciated in terms of their functional contributions to cardiac development and physiology, they and their activated form, myofibroblasts, are now known to play key roles in both development and disease through structural, paracrine, and electrical interactions with cardiomyocytes. The lack of specific markers for fibroblasts currently convolutes the study of this dynamic cell lineage, but advances in marker analysis and lineage mapping technologies are continuously being made. Understanding how to best utilize these tools, both individually and in combination, will help to elucidate the functional significance of fibroblast–cardiomyocyte interactions in vivo . Here we review what is currently known about the diverse roles played by cardiac fibroblasts and myofibroblasts throughout development and periods of injury with the intent of emphasizing the duality of their nature. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium ".