cssi/SciSciGPT-SciSciNet huggingface dataset:
ON ELIMINATION THROUGH THE MUCOSA OF THE URINARY BLADDER

In a previous communication (Journal of Exper. Medicine, XIV, 274, 1911), I stated that after intravenous injections of large amounts of dextrose the intestine contained on the average 1.2 per cent. of the injected amount of destrose and in nephrectomized animals the dextrose content of the intestine reached the average of 2.2 per cent. The question arose then whether in the presence of a strong hyperglycemia, and especially after double nephrectomy, all mucous membranes are slightly permeable to this substance. The presence of measurable quantities of dextrose in the gastro-intestinal canal is no evidence for the permeability of the mucosa as such, since the mucous membrane of this organ is studded with numerous glandular structures which may readily be instrumental in the removal from the blood of substances present there in excess. In the experiments I wish to communicate here, I selected, therefore, the bladder for the study of this problem since the mucous lining of this organ is practically the only...
Kazhdan's property T and C∗-algebras

Abstract Kazhdan's property T has recently been imported to the C ∗ -world by Bekka. Our objective is to extend a well-known fact to this realm; we show that a nuclear C ∗ -algebra with property T is finite-dimensional (for all intents and purposes). Though the result is not surprising, the proof is a bit more complicated than the group case.
Synthesis and photophysics of new types of fullerene-porphyrin dyads

Abstract The synthesis and photophysical properties of three types of porphyrin–fullerene (P-C 60 ) dyads are presented: (a) conformationally flexible dyads with polyether linkers, (b) rigid dyads with steroid linkers, and (c) a parachute-shaped dyad in which the flat porphyrin and spherical fullerene chromophores are in very close proximity. The course of events following photoexcitation of these dyads and (in some cases) corresponding porphyrin–zinc complexes has been probed through studies of fluorescence quenching, measurements of fluorescence lifetimes and quantum yields for singlet molecular oxygen formation, and transient absorption spectroscopy. These data provide insight into the dynamic competition between intramolecular energy transfer and electron transfer in these dyads, and, for the case of the parachute-shaped dyad, the kinetics of back-electron transfer.
The Identification of Quasars behind Elliptical Galaxies and Clusters of Galaxies

The detection of resonance absorption lines against known objects such as individual galaxies and clusters of galaxies is a powerful approach for studying the gas content of these systems. We describe an efficient method of identifying background quasars suitable for absorption-line studies. In this finding technique, we identify serendipitous X-ray sources, about one-eighth of which are suitably bright quasars at moderate redshift. We identify 16 new quasars and galaxies with active galactic nuclei (AGNs) and confirm five known quasars and AGNs, superposed behind elliptical galaxies and clusters of galaxies. We also present three QSO/AGN candidates with uncertain redshift identifications.
Molecular Tools and Approaches for Optogenetics

The mammalian brain poses a formidable challenge to the study and treatment of neuropsychiatric diseases, owing to the complex interaction of genetic, epigenetic, and circuit-level mechanisms underlying pathogenesis. Technologies that facilitate functional dissection of distinct brain circuits are necessary for systematic identification of disease origin and therapy. Recent developments in optogenetics technology have begun to address this challenge by enabling precise perturbation of distinct cell types based on molecular signatures, functional projections, and intracellular biochemical signaling pathways. With high temporal precision and reversible neuromodulation, optogenetics promises to improve existing disease models and advance our understanding of psychiatric conditions. In this review, we describe the current state of molecular optogenetic tools and future directions of development.
CP Conservation in the Presence of Pseudoparticles

We give an explanation of the $\mathrm{CP}$ conservation of strong interactions which includes the effects of pseudoparticles. We find it is a natural result for any theory where at least one flavor of fermion acquires its mass through a Yukawa coupling to a scalar field which has nonvanishing vacuum expectation value.
Markov Extensions for Dynamical Systems with Holes: An Application to Expanding Maps of the Interval

We introduce the Markov extension, represented schematically as a tower, to the study of dynamical systems with holes. For tower maps with small holes, we prove the existence of conditionally invariant probability measures which are absolutely continuous with respect to Lebesgue measure (abbreviated a.c.c.i.m.). We develop restrictions on the Lebesgue measure of the holes and simple conditions on the dynamics of the tower which ensure existence and uniqueness in a class of Holder continuous densities. We then use these results to study the existence and properties of a.c.c.i.m. forC1+α expanding maps of the interval with holes. We obtain the convergence of the a.c.c.i.m. to the SRB measure of the corresponding closed system as the measure of the hole shrinks to zero.
On the value of restrictive covenants: Empirical investigation of public bond issues

Abstract Are restrictive covenants effective mechanisms in mitigating agency problems? Is the magnitude of the increase in the cost of debt due to agency problems non-trivial? We tackle these questions using a large dataset of public bonds. Contrary to the view that restrictive covenants in public bond contracts are standard boilerplates that serve little purpose, we find significant benefits in terms of reduction in the cost of debt associated with covenants. Restrictions on investment activities or issuance of higher priority claims reduce the cost of debt by about 35–75 basis points. These findings suggest that investors view bond covenants as important instruments in mitigating agency problems, and an increase in the cost of debt due to agency problems could be substantial. Additionally, we find that high growth firms and firms with low probability of default are less likely to include covenants suggesting that the costs of covenants outweigh benefits for these types of firms.
Integrable narrow-band model with possible relevance to heavy-fermion systems.

A lattice model consisting of a single narrow band is introduced to describe some aspects of heavy electrons. The model excludes double occupancy of the sites and electrons on nearest-neighbor sites interact via a charge interaction and spin exchange. The model is integrable in one dimension for some special values of the coupling constants. These cases are related to the SU(3) invariance. The Bethe-ansatz equations are obtained and ground-state and thermodynamic properties are discussed and solved in some limiting cases.
The ionized nuclear environment in NGC 985 as seen by Chandra and BeppoSAX

We investigate the ionized environment of the Seyfert 1 galaxy NGC 985 with a new Chandra HETGS observation and an archival BeppoSAX observation. Both spectra exhibit strong residuals to a single-power-law model, indicating the presence of an ionized absorber and a soft excess. A detailed model over the Chandra data shows that the 0.6-8 keV intrinsic continuum can be well represented by a power law (Γ ≈ 1.6) plus a blackbody component (kT = 0.1 keV). Two absorption components are clearly required to fit the absorption features observed in the Chandra spectrum. The components have a difference of 29 in ionization parameter and 3 in column density. The presence of the low-ionization component is evidenced by an Fe M-shell unresolved transition array produced by charge states VII-XIII. The high-ionization phase is required by the presence of broad absorption features arising from several blends of Fe L-shell transitions (Fe XVII-XXII). A third highly ionized component might also be present, but the data do not allow us to constrain its properties. Although poorly constrained, the outflow velocities of the components (581 ± 206 km s-1 for the high-ionization phase and 197 ± 184 km s-1 for the low-ionization one) are consistent with each other and with the outflow velocities of the absorption components observed in the UV. In addition, the low-ionization component produces significant amounts of O VI, N V, and C IV, which suggests that a single outflow produces the UV and X-ray features. The broadband (0.1-100 keV) continuum in the BeppoSAX data can be parameterized by a power law (Γ ≈ 1.4), a blackbody (kT = 0.1 keV), and a high-energy cutoff (Ec ≈ 70 keV). An X-ray luminosity variation by a factor of 2.3 is observed between the BeppoSAX and Chandra observations (separated by almost 3 yr). Variability in the opacity of the absorbers is detected in response to the continuum variation, but while the colder component is consistent with a simple picture of photoionization equilibrium, the ionization state of the hotter component seems to increase, while the continuum flux drops. The most striking result in our analysis is that during both the Chandra and the BeppoSAX observations, the two absorbing components appear to have the same pressure. Thus, we suggest that the absorption arises from a multiphase wind. Such a scenario can explain the change in the opacity of both absorption components during the observations, but it requires that a third, hotter component be pressure-confining the two phases. Hence, our analysis points to a three-phase medium similar to the wind found in NGC 3783, and it further suggests that such a wind might be a common characteristic in active galactic nuclei. The pressure-confining scenario requires fragmentation of the confined phases into a large number of clouds.
Regiochemical Control by Remote Substituents – A Selective Synthesis of Angularly Fused Ring Systems

Diels–Alder reactions of quinones 4, 7, and 15 exhibit remarkable regioselectivity. In contrast, the Diels–Alder reaction of quinone 12 showed no regioselectivity, indicating that the regioselectivities are due to electronic interactions. The selectivity is nicely explained using molecular electrostatic potentials. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Condensed-matter research at the Los Alamos pulsed neutron source (WNR)

Abstract The experimental program at the WNR in condensed matter research at present is aimed principally at utilizing the high epithermal neutron flux available at a spallation neutron source. Interesting new results have been obtained in several areas including hydrogen vibrations in metals, chemical vibrational spectroscopy and the structure of liquids. For example, extensive vibrational spectra were obtained by hydrogen in Nb which could be described in terms of a three-dimensional localized anharmonic oscillator, deuterium substitution methods were used to determine the variation with O-O distance of the hydrogen bending mode frequency in extremely short intramolecular hydrogen bonds, and model-independent partial structure factors were determine for liquid water.
Chiral crystallization and the origin of chiral life on earth

The creation of chirality on Earth and the development of chiral life have been discussed in this highlight. Convincing evidence for the introduction of chirality on Earth is still fragmentary. We believe that by a combination of chiral crystallization and formation of helical polymers with preferred chiral conformational structure is the key to this question. This concept of macromolecular asymmetry has inspired ideas and resulted in possible rules for how chiral life as we know it, could have been introduced. These investigations needed the understanding of the requirements for chiral crystallization, for the stereochemistry of the initial formation of helical polymers, the measurements of optical activity of solids and their coordination with the fundamentals of chirality. Spacial modeling of the “oligo-crystallization” of sodium chlorate led to the conception of “isotactic” linear crystallization, which involves helical propagation. It seems to require unequal sizes of the cations and anions, which, by branching propagation leads to three-dimensional chiral crystal formation. Linear “isotactic” propagation of crystallization seems to be equivalent to stereo and conformational specific polymerization. One and a half turns of the helix seems to be required for stereo- and conformational specificity, that is, between the pentamer and hexamer in chloral polymerization (11/3 or nearly 4/1 helix) and between trimer and tetramer for the sodium chlorate crystal (2/1 helix). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Parameters that predict local control after definitive radiotherapy for squamous cell carcinoma of the head and neck.

Purpose. To analyze parameters that may influence the likelihood of local control after definitive radiotherapy for head and neck cancer. Methods. Between April 1980 and January 2000, 404 patients were treated with definitive RT alone (358 patients) or combined with adjuvant chemotherapy (46 patients) at our institution and were followed up for 0.25 to 20.25 years (median, 3.5 years.) All living patients were followed up for at least 2 years. All patients had the primary tumor volume calculated on pretreatment CT. End points were local control after RT and local control after RT without a severe late complication. Parameters evaluated in multivariate analyses of these end points included primary site, T stage, primary tumor volume, N stage, histologic differentiation, fractionation schedule, adjuvant chemotherapy, and gender. Results. The rates of local control and local control without a severe late complication after RT were significantly influenced by primary tumor volume for patients with cancer of the supraglottic larynx and true vocal cord. In contrast, the rates of local control and local control without severe complications for patients with tumors of the oropharynx and hypopharynx were less influenced by tumor volume. Multivariate analysis of the overall population revealed that the only parameter that was significantly related to the probability of local control after RT was T stage. Multivariate analyses stratified by primary site revealed that tumor volume significantly influenced local control for patients with cancers of the supraglottis (p = .0220) and glottis (p = .0042) but not for those with lesions of the tonsillar fossa/posterior tonsillar pillar (p = .0892), base of tongue (p = .9493), anterior tonsillar pillar/soft palate (p = .5909), and hypopharynx (p = .2282). Conclusions. The most important parameter that has an impact on local control after RT is T stage. Primary tumor volume also significantly influences the probability of local control in cancers of the supraglottis and glottis. © 2003 Wiley Periodicals, Inc. Head Neck 25: 535–542, 2003
CO2 Flow Patterns Under Multiphase Flow: Heterogeneous Field-Scale Conditions

A finite-difference, equation-of-state (EOS), compositional simulator has been used to study CO[sub 2] flooding. First, unstable first-contact-miscible (FCM) displacements were simulated with a fine mesh to investigate the transition from gravity override to viscous fingering. Next, a direct comparison was made for FCM and multiple-contact-miscible (MCM) displacements under the same conditions to investigate effects of phase behavior on the growth of viscous fingers. Then, the effects of gravity, physical dispersion, capillary pressure, phase behavior, and heterogeneity were combined and simulated for CO[sub 2] flooding on a field scale with stochastic permeability fields.
Biosynthetic medicinal chemistry of natural product drugs

Natural products are an unsurpassed source of lead structures for drug discovery. However, these molecules, many of which fall into the beyond-rule-of-5 chemical space, are often difficult to optimize by chemical means because of their complex structures. Biosynthetic engineering of the producing host organism offers an important tool for the modification of complex natural products, leading to analogues which are unattainable by chemical semisynthesis. This review describes the current role of natural products in lead generation and the principles behind biosynthetic medicinal chemistry. It then goes on to describe five distinct drugs – salinosporamide, geldanamycin, FK506, rapamycin and epothilone – to exemplify how biosynthetic engineering approaches have contributed to the advancement of natural product clinical candidates.
Naturally Weak CP Violation

Ab SU(5) GUT model is proposed in which the observed CP violation is due to spontaneous symmetry breakdown. The effective field theory below the GUT scale is simply the standard model. Matching conditions at the GUT scale give a non-zero contribution to θ at the one-loop level. This contribution is proportional to ratios of superheavy fermion masses over the GUT scale, which can be naturally small, in the sense of't Hooft.
Studies of zoanthamine alkaloids. Enantiocontrolled construction of the tetracyclic hemi-aminal core

Abstract A concise enantiocontrolled synthesis of the enamine-aminal heterocyclic core found in the zoanthamine alkaloids is presented. Conjugate addition of a chiral imine provides for excellent diastereofacial selectivity in the generation of the quaternary C 9 asymmetry of 4 .
Reproductive behavior of free-ranging Lemur catta at Beza Mahafaly Special Reserve, Madagascar

Observations of reproductive behavior in free-ranging Lemur catta were carried out during one annual cycle. Variability in the behavior of female ringtailed lemurs during parturition appears to be mainly a function of the female's parity and thus her experience. Females within a troop show estrous asynchrony and characteristically mate with more than one male. Females also exhibit proceptive behavior toward and mate with some males from other troops and with transferring males. The potential for a male to monopolize mating opportunities during a female's short estrous period is therefore limited. Male mating strategies in ringtailed lemurs can be seen as adaptations to female mate choice during a highly restricted breeding season. In this species the dominance hierarchy does not break down with regard to the order of mating. The highest ranking male (central male) mates first and shows precopulatory guarding and longer postejaculatory guarding, which may increase his chances of siring the offspring. Subsequent mating partners have developed various counterstrategies to mitigate mating order effects.
Critique of a pion exchange model for interquark forces

I describe four serious defects of a widely discussed pion exchange model for interquark forces: it does not solve the ''spin-orbit problem'' as advertised, it fails to describe the internal structure of baryon resonances, it leads to disastrous conclusions when extended to mesons, and it is not reasonably connected to the physics of heavy-light systems. While extensions of the original pion exchange model may be able to correct these defects, this catalogue of criticisms defines some of the most formidable problems such elaborations must address. (c) 2000 The American Physical Society.
Nonlinear Pricing and Oligopoly

We consider the general problem of price discrimination with nonlinear pricing in an oligopoly setting where firms are spatially differentiated. We characterize the nature of optimal pricing schedules, which in turn depends importantly upon the type of private inflation the customer possesses - either horizontal uncertainty regarding brand preference or vertical uncertainty regarding quality preference. We show that as competition increases, the resulting quality distortions decrease, as well as price and quality dispersions. Additionally, we indicate conditions under which price discrimination may raise social welfare by increasing consumer surplus through encouraging greater entry.
Entrepreneurial Geographies: Support Networks in Three High-Technology Industries

Using a unique database derived from prospectuses for U.S. initial public stock offerings, we examine the location of four actors (the firm's lawyers, the venture capitalists on the board of directors, the other members of the board of directors, and the lead investment banker) of the entrepreneurial support network for startup firms in three high-technology industries: semiconductors, telecommunica- tions equipment, and biotechnology. We demonstrate that the economic geog- raphy of the biotechnology support network differs significantly from the networks in semiconductors and telecommunications equipment. Biotechnology has a far- more-dispersed entrepreneurial support network structure than do the two elec- tronics-related industries. The case of biotechnology indicates that if the source of seeds for new firms is highly dispersed, then an industry may not experience the path-dependent clustering suggested by geographers. We argue that contrary to common belief, biotechnology and its support network do not exhibit as great a clus- tering as do semiconductors and telecommunications equipment and their support networks. This argument leads to an epistemological issue, namely, the lack. of interindustry comparative work. This is an odd omission, since nearly all authors agree that industries are based on particular knowledge bases, yet few consider that the knowledge and the sources of it may have an impact on spatial distributions.
Physicians, medical ethics, and execution by lethal injection.

In an opinion dissenting from a Supreme Court decision to deny review in a death penalty case, Supreme Court Justice Harry Blackmun famously wrote, “From this day forward, I no longer shall tinker with the machinery of death.”1 In the wake of the recent botched execution by lethal injection in Oklahoma, however, a group of eminent legal professionals known as the Death Penalty Committee of The Constitution Project has published a sweeping set of 39 recommendations that not only tinker with, but hope to fix, the multitude of problems that affect this method of capital punishment.2
Mitigating the sign problem for non-relativistic fermions on the lattice

We study the fermion sign problem in a theory of non-relativistic fermions with a spin-independent repulsive interaction. We work in polar co-ordinates in momentum space, which makes it straightforward to keep only the low-energy degrees of freedom close to the Fermi surface. This is sufficient for the purpose of calculating many physically important low-energy observables. We find indications that the sign problem in this effective theory will be weaker than in the full theory, so low-energy properties of the theory could be calculated by modifying the action to make it positive semi-definite and including reweighting factors in the observables. We discuss suitable modifications of the action, and describe a possible lattice realization of the polar momentum space formulation of the theory.
Preparation of the Binary Technetium Bromides: TcBr3 and TcBr4

TcBr3 (1) and TcBr4 (2) were synthesized by reaction of Tc metal with elemental bromine at 400 °C. Single crystal XRD measurements indicate that TcBr3 crystallizes in the orthorhombic space group Pmmn (a = 11.0656(2) A, b = 5.9717(1) A, c = 6.3870(1) A). The structure consists of infinite chains of face-sharing TcBr6 octahedra with a regular alternation of short and long Tc−Tc distances (2.8283(4) A, 3.1434(4) A). TcBr4 crystallizes in the orthorhombic space group Pbca (a = 6.3237(5) A, b = 12.1777(9) A, c = 14.7397(11) A). TcBr4 contains infinite chains of edge-sharing TcBr6 octahedra with no apparent metal−metal bond (Tc−Tc = 3.7914(4) A). Technetium tribromide is isomorphous with RuBr3 and MoBr3, while TcBr4 is isomorphous with PtBr4 and OsBr4.
Theory of the resistance minimum in dilute paramagnetic alloys

Abstract The observed anomalous temperature dependence of the resistivity of dilute paramagnetic alloys is attributed to s - d exchange scattering of conduction electrons by nearest neighbor pairs of ferromagnetically coupled solutions. Occurrence of a resistance minimum can be explained quantitatively only if the effective range of the s - d exchange potential is not too short; and only if the periodic structure of energy bands is taken into account. The size of the minimum is proportional to the square of the solute concentration in the limit of extreme dilution (less than 1 per cent). Deviations from this law at higher concentrations are explained satisfactorily.
Next-to-Leading-Order Staggered Chiral Perturbation Theory

We have extended staggered chiral perturbation theory (SχPT) to O ( a 2 p 2 ) , O ( a 4 ) , and O ( a 2 m ) , the orders necessary for a full next-to-leading order (NLO) calculation of pseudo-Goldstone boson (PGB) masses and decay constants including taste-symmetry violations. We present predictions relating S O ( 4 ) taste-breaking splittings in masses, pseudoscalar decay constants, and dispersion relations. These can be used to test the D e t 4 trick.
Synthesis, crystal structures, and physical properties of the new Zintl phases A21Zn4Pn18 (A=Ca, Eu; Pn=As, Sb)—Versatile arrangements of [ZnPn4] tetrahedra

Four new Zintl phases, Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18}, Eu{sub 21}Zn{sub 4}As{sub 18} and Eu{sub 21}Zn{sub 4}Sb{sub 18} have been synthesized by metal flux reactions. Their structures have been established from single-crystal X-ray diffraction. Despite the similar chemical makeup and the identical formulae, the structures of the four compounds are not the same—Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18} and Eu{sub 21}Zn{sub 4}As{sub 18} crystallize in the monoclinic space group C2/m (No. 12, Z=4) with the β-Ca{sub 21}Mn{sub 4}Sb{sub 18} structure type, while Eu{sub 21}Zn{sub 4}Sb{sub 18} adopts the Ba{sub 21}Cd{sub 4}Sb{sub 18} structure type with the orthorhombic space group Cmce (No. 64, Z=8). Both structures are based on ZnAs{sub 4} or ZnSb{sub 4} tetrahedra, linked in slightly different ways, and Ca{sup 2+} and Eu{sup 2+} cations that fill the space between them. The structural relationships between the title compounds and other known ternary phases with intricate structures are discussed. Electrical resistivity measurement on single-crystalline Eu{sub 21}Zn{sub 4}Sb{sub 18} suggests an intrinsic semiconductor behavior with a band gap of ca. 0.2 eV. The temperature dependent DC magnetization measurement on the same material indicates Curie–Weiss paramagnetism in the high-temperature regime, and a spontaneous antiferromagnetic ordering below 8more » K. The calculated effective moments of Eu confirm the divalent Eu{sup 2+} ground state, as expected from the Zintl–Klemm concept. - Graphical abstract: The four new Zintl phases—Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18}, Eu{sub 21}Zn{sub 4}As{sub 18}, and Eu{sub 21}Zn{sub 4}Sb{sub 18}—crystallize in two structure types, showing the versatility in the arrangements of ZnAs{sub 4} and ZnSb{sub 4} tetrahedra. - Highlights: • Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18}, Eu{sub 21}Zn{sub 4}As{sub 18}, and Eu{sub 21}Zn{sub 4}Sb{sub 18} are new compounds in the respective ternary phase diagrams. • They form with structure types, showing the versatility in the arrangements of ZnAs{sub 4} and ZnSb{sub 4} tetrahedra. • For both structures, the valence electron count follows the Zintl–Klemm rules.« less
Fermion bags in the massive Gross-Neveu model

Abstract As has long been known, it is energetically favorable for massive fermions to deform the homogeneous vacuum around them, giving rise to extended bag-like objects. We study this phenomenon non-perturbatively in a model field theory, the 1 + 1 dimensional Massive Gross-Neveu model, in the large N limit. We prove that the bags in this model are necessarily time dependent. We calculate their masses variationally and demonstrate their stability. We find a non-analytic behavior in these masses as we approach the standard massless Gross-Neveu model and argue that this behavior is caused by the kink-antikink threshold. This work extends our previous work to a non-integrable field theory.
Ionization Density Effects in Spark Chambers

During the course of an experiment on the decay properties of ?° particles we observed qualitatively an ionization effect. The sparks of the heavily ionizing proton were bright and had 100% gap efficiency. The sparks of the minimum ionizing pion are weak and have a low gap efficiency. These observations are studied quantitatively in this paper.
Radiation-perturbed flow fields of normal and oblique shock waves

Flow field perturbations due to radiative transfer behind normal and oblique shock waves are studied. For steady, two-dimensional flow, the perturbation equations of motion reduce to Poisson and wave equations for subsonic and supersonic flow, respectively, with source terms determined by the radiative transfer. Consideration of boundary conditions yields general solutions, which can include the effects of absorption ahead of the shock and external radiation sources such as emitting or reflecting boundaries. For a normal shock with radiant-energy transfer parallel to the shock front, the perturbed flow variables and shock curvature are determined. Introduction of an approximation for the radiative transfer term in the oblique shock (supersonic wedge) case, yields explicit solutions for the perturbed flow variables and shock curvature. These analyses are valid for either frozen or equilibrium flow, and the effects of self-absorption are included, with explicit results being obtained for a gray gas and a gas with nonoverlapping spectral lines described by collision-broadened profiles.
Understanding networks and their behaviors using sheaf theory

Many complicated network problems can be easily understood on small networks. Difficulties arise when small networks are combined into larger ones. Fortunately, the mathematical theory of sheaves was constructed to address just this kind of situation; it extends locally-defined structures to globally valid inferences by way of consistency relations. This paper exhibits examples in network monitoring and filter hardware where sheaves have useful descriptive power.
Interactions between child and parent temperament and child behavior problems

Abstract Objective Few studies of temperament have tested goodness-of-fit theories of child behavior problems. In this study, we test the hypothesis that interactions between child and parent temperament dimensions predict levels of child psychopathology after controlling for the effects of these dimensions individually. Methods Temperament and psychopathology were assessed in a total of 175 children (97 boys, 78 girls; mean age, 10.99 years; SD, 3.66 years) using composite scores from multiple informants of the Junior Temperament and Character Inventory and the Achenbach System of Empirically Based Assessment. Parent temperament was assessed using the adult version of the Temperament and Character Inventory. Statistical analyses included multiple regression procedures to assess the contribution of child-parent temperament interactions after controlling for demographic variables, other types of child psychopathology, and the individual Temperament and Character Inventory and Junior Temperament and Character Inventory dimensions. Results Interactions between child and parent temperament dimensions predicted higher levels of externalizing, internalizing, and attention problems over and above the effects of these dimensions alone. Among others, the combination of high child novelty seeking with high maternal novelty was associated with child attention problems, whereas the combination of high child harm avoidance and high father harm avoidance was associated with increased child internalizing problems. Many child temperament dimensions also exerted significant effects independently. Conclusions The association between a child temperament trait and psychopathology can be dependent upon the temperament of parents. These data lend support to previous theories of the importance of goodness-of-fit.
Synthesis of p-Quinquephenyl from E,E-1,4-Bis(4-bromophenyl)-1,3-butadiene

p-Quinquephenyl was synthesized in five steps from E,E-1,4-bis(4-bromophenyl)-1,3-butadiene in 34% overall yield. The butadiene was prepared in six steps from 4-bromobenzaldehyde in 35% overall yield.
Ram Pressure Stripping in Clusters and Groups

Ram pressure stripping is an important process in the evolution of both dwarf galaxies and large spirals. Large spirals are severely stripped in rich clusters and may be mildly stripped in groups. Dwarf galaxies can be severely stripped in both clusters and groups. A model is developed that describes the stripping of a satellite galaxy's outer H I disk and hot galactic halo. The model can be applied to a wide range of environments and satellite galaxy masses. Whether ram pressure stripping of the outer disk or hot galactic halo occurs is found to depend primarily on the ratio of the satellite galaxy mass to the mass of the host group or cluster. How the effectiveness of ram pressure stripping depends on the density of the intergroup gas, the dark matter halo concentrations, and the scale lengths and masses of the satellite components is explored. The predictions of the model are shown to be well matched to H I observations of spirals in a sample of nearby clusters. The model is used to predict the range of H I gas fractions that a satellite of mass Mv,sat can lose orbiting in a cluster of mass Mv,gr.
Simulations among multidimensional turing machines

Abstract For all d ⩾ 1 and all e >d, every deterministic multihead e-dimensional Turing machine of time complexity T(n) can be simulated on-line by a deterministic multihead d-dimensional Turing machine in time O(T(n)1+1⧸d−1⧸(log T(n))0(1)). This simulation almost achieves the known lower bound Ω(T(n) 1+1⧸ d−1⧸e) on the time required. The simulation is interpreted in terms of dynamic embeddings among arrays with local access.
From Macdonald polynomials to a charge statistic beyond type A

The charge is an intricate statistic on words, due to Lascoux and Schutzenberger, which gives positive combinatorial formulas for Lusztig@?s t-analogue of weight multiplicities and the energy function on affine crystals, both of type A. As these concepts are defined for all Lie types, it has been a long-standing problem to express them based on a generalization of charge. I present a method for addressing this problem in classical Lie types, based on the recent Ram-Yip formula for Macdonald polynomials and the quantum Bruhat order on the corresponding Weyl group. The details of the method are carried out in type A (where we recover the classical charge) and type C (where we define a new statistic).
The ACS Nearby Galaxy Survey Treasury. III. Cepheids in the Outer Disk of M81

The ACS Nearby Galaxy Survey Treasury (ANGST) has acquired deep ACS imaging of a field in the outer disk of the large spiral galaxy M81. These data were obtained over a total of 20 Hubble Space Telescope orbits, providing a baseline long enough to reliably identify Cepheid variable stars in the field. Fundamental mode and first overtone types have been distinguished through comparative fits with corresponding Cepheid light curve templates derived from principal component analysis of confirmed Cepheids in the Large Magellanic Cloud (LMC), Small Magellanic Cloud, and Milky Way. A distance modulus of 27.78 ± 0.05 r ± 0.14 s with a corresponding distance of 3.60 ± 0.23 Mpc has been calculated from a sample of 11 fundamental mode and two first overtone Cepheids (assuming an LMC distance modulus of μLMC = 18.41 ± 0.10 r ± 0.13 s ).
Experiments on spatio-temporal chaos

Abstract Under non-equilibrium conditions, a spatially-extended system will often undergo a transition from a uniform state to a state with spatial variation (a “pattern”). Patterns are of interest because their formation is associated with non-linear effects which can lead to qualitatively new phenomena that do not occur in linear systems. Among the most fascinating of these phenomena is spatio-temporal chaos (STC). This paper briefly reviews some of the experimental observations of and measurements on STC.
Effective viscosity of dilute bacterial suspensions: a two-dimensional model

Suspensions of self-propelled particles are studied in the framework of two-dimensional (2D) Stokesean hydrodynamics. A formula is obtained for the effective viscosity of such suspensions in the limit of small concentrations. This formula includes the two terms that are found in the 2D version of Einstein's classical result for passive suspensions. To this, the main result of the paper is added, an additional term due to self-propulsion which depends on the physical and geometric properties of the active suspension. This term explains the experimental observation of a decrease in effective viscosity in active suspensions.
Mill processability of cis-1,4-polybutadienes and deformational characteristics

Mill behavior was examined with gum rubbers and carbon black-filled compounds of different types of cis-1,4-polybutadiene. The rubbers were Ti-, Nd-, and Co-polymerized polymers. The Co-polymerized rubber contained crystalline particles of 1,2-polybutadiene. The carbon black was 50 phr N330. Photographs of the samples on the mill were taken after milling for 2 min. The mill behaviors were classified according to the four regions of Tokita and White. Behavior at loading, stickiness, and mill shrinkage were evaluated qualitatively to interpret mill behavior with aid of the deformational data of previous publications. The Ti-rubber, containing relatively short branches and exhibiting a strain-softening, was in Region III. The Nd-rubbers, containing relatively long branches and exhibiting a strain-hardening, tended to go to Region IV, because the degree of branching was low. The Co-rubbers containing crystalline particles were in Region II, even though they gave strain-softening since they had a high modulus because of the presence of the particles. An overriding effect on the mill behavior appeared to come from how high the modulus of the gum rubber was at the milling condition. Both the gum rubber and the corresponding compound were in the same region of the mill processability. The strain-induced crystallization occurred only when the compounds were under tension on the mill. i.e.. Region II.
The Busemann-Petty problem for arbitrary measures

The Busemann-Petty problem asks whether symmetric convex bodies in ℝ n with smaller (n−1)-dimensional volume of central hyperplane sections necessarily have smaller n-dimensional volume. The answer to this problem is affirmative for n≤4 and negative for n≥5. In this paper we generalize the Busemann-Petty problem to essentially arbitrary measure in place of the volume. We also present applications of the latter result by proving several inequalities concerning the measure of sections of convex symmetric bodies in ℝ n .
Blue companions of Cepheids

Twenty-one Cepheids, known or suspected to have blue companions, were studied with the International Ultraviolet Explorer satellite. For 13 of them, companions were indeed seen, though they were generally fainter in the UV than expected. For four Population I Cepheids, the suspected companions were not seen. For none of the Population II Cepheids could a companion be detected. The effective temperatures and luminosities of the companions which could be observed are discussed, and the positions of Cepheids and companions in the T(eff) luminosity diagrams are compared with positions expected from stellar evolution calculations.
Asynchronous Logic Circuits and Sheaf Obstructions

This article exhibits a particular encoding of logic circuits into a sheaf formalism. The central result of this article is that there exists strictly more information available to a circuit designer in this setting than exists in static truth tables, but less than exists in event-level simulation. This information is related to the timing behavior of the logic circuits, and thereby provides a ''bridge'' between static logic analysis and detailed simulation.
Prescription for experimental determination of the dynamics of a quantum black box

Abstract We give an explicit way to experimentally determine the evolution operators which completely describe the dynamics of a quantum-mechanical black box: an arbitrary open quantum system. We show necessary and sufficient conditions for this to be possible and illustrate the general theory by considering specifically one-and two-quantum-bit systems. These procedures may be useful in the comparative evaluation of experimental quantum measurement, communication and computation systems.
Effects of LWR Coolant Environments on Fatigue Lives of Austenitic Stainless Steels

Fatigue tests have been conducted on Types 304 and 316NG stainless steels to evaluate the effects of various material and loading variables, e.g., steel type, strain rate, dissolved oxygen (DO) in water, and strain range, on the fatigue lives of these steels. The results confirm significant decreases in fatigue life in water. Unlike the situation with ferritic steels, environmental effects on Types 304 and 316NG stainless steel are more pronounced in low-DO than in high-DO water. Experimental results have been compared with estimates of fatigue life based on a statistical model. The formation and growth of fatigue cracks in air and water environments are discussed.
An Introduction to Thermodynamics and Statistical Mechanics

Preface Part I. Introduction: 1. Introduction Part II. Small Systems: 2. Statistics for small systems 3. Systems with many elements Part III. Energy and the First Law: 4. Internal energy 5. Interactions between systems Part IV. States and the Second Law: 6. Internal energy and the number of accessible states 7. Entropy and the second law 8. Entropy and thermal interactions Part V. Constraints: 9. Natural constraints 10. Models 11. Choice of variables 12. Special processes 13. Engines 14. Diffusive interactions Part VI. Classical Statistics: 15. Probabilities and microscopic behaviours 16. Kinetic theory and transport processes in gases 17. Magnetic properties of materials 18. The partition function Part VII. Quantum Statistics: 19. Introduction to quantum statistics 20. Quantum gases 21. Blackbody radiation 22. The thermal properties of solids 23. The electrical properties of materials 24. Low temperatures and degenerate systems Appendices Further reading Problem solutions Index.
Hypervelocity Heat Protection- A Review of Laboratory Experiments

Hypervelocity heat protection, surface heat shielding, and internal temperature rise of Teflon, phenolic nylon, epoxy resin in glass honeycomb, and silicone elastomer
Drivers of variability in water use of native and non-native urban trees in the greater Los Angeles area

Trees in urban ecosystems are valued for shade and cooling effects, reduction of CO2 emissions and pollution, and aesthetics. However, in arid and semi-arid regions, urban trees must be maintained through supplemental irrigation, in competition with other water needs. Currently, a comprehensive understanding of the factors which influence water use of urban tree species is lacking. In order to study the drivers of whole tree water use of two common species in the Los Angeles Basin urban forest, four sites in Los Angeles and Orange County were instrumented with sap flow and meteorological sensors. These sites allowed comparisons of the water use of a native riparian (Platanus racemosa Nutt.; California sycamore) and non-native (Pinus canariensis C. Sm.; Canary Island pine) Mediterranean species, as well as the spatial variability in water use under different environmental and management conditions. We found higher rates of sapflux (J O ) in native California sycamore as compared to non-native Canary Island pine. Within each species, we found considerable site-to-site variability in the magnitude and seasonality of J O . For Canary Island pine, the majority of inter-site variability derived from differences in water availability: response to vapor pressure deficit was similar during a period without water limitations. In contrast, California sycamore did not appear to experience water limitation at any site; however, there was considerable spatial variability in water use, potentially linked to differences in nutrient availability. Whole tree transpiration (E) was similar for the two species when water was not limiting, but Canary Island pine was able to withstand unirrigated conditions with a very low E. These results add to the currently small pool of data on urban tree water use and ecophysiology, and contribute to establishing a more quantitative understanding of urban tree function.
Light Absorption in Strongly Irradiated Long Range Polar Electron Transfer Systems.

Light absorption of long range electron transfer (ET) complexes immersed in polar solvents is analyzed. At sufficiently high laser intensities absorption or emission of multiple photon quanta occurs. In addition, the equilibrium population of the two donor and acceptor electronic states is strongly perturbed from its field-off value. The combination of these two effects results in dramatic variations in the frequency dependence of the absorption cross section as a function of laser intensity. Certain bands in the absorption spectrum can be eliminated simply by changing the laser intensity. For commonly utilized mixed-valence transition metal ET complexes and polar solvents an applied electric field strength of {approx_equal}10{sup 7} V/cm should be sufficient to induce noticeable changes in the weak-field spectrum. {copyright} {ital 1996 The American Physical Society.}
Regional differences in the lung

Marked differences of ventilation, blood flow, gas exchange, alveolar size, intrapleural pressures and mechanical stresses exist within the human lung and some of these are of special interest to the anesthesiologist in the context of anesthesia and postoperative care.
Structure and diffusion time scales of disordered clusters

Abstract The eigenvalue spectra of the transition probability matrix for random walks traversing critically disordered clusters in three different types of percolation problems show that the random walker sees a developing Euclidean signature for short time scales as the local, full-coordination constraint is iteratively applied.
The Hagedorn thermostat

At variance with previous understanding, a system with a Hagedorn-like mass spectrum can sustain the unique temperature T encoded in the spectrum itself. imposes the same temperature to all emitted particles which are then in physical and chemical equilibrium with and with each other. Coexistence between hadronic and partonic phases is thus completely characterized. This may explain the recurring constant physical and chemical temperature observed in several experiments. The near indifference of to fragmentation or coalescence makes this approach relevant to heavy-ion and elementary-particle collisions alike. The equation of state for a gas of systems has been derived.
Dynamic Effort, Sustainability, Myopia, and 110% Effort

By definition, giving 100% effort all of the time is sustainable, but begs the question of how to define 100% effort. As a corollary, once a benchmark for defining 100% effort is chosen, it may be possible, even optimal, to give a greater amount of effort for a short period of time, while recognizing that this level of effort is not sustainable. This dynamic effort provision problem is analyzed in the context of effort and performance by National Basketball Association (NBA) players over the course of a season. Within this context, several benchmarks for sustainable effort are considered, but these are rejected by the data. Meanwhile, the data are consistent with the proposition that NBA players put forth optimal effort, even if such effort is not always sustainable.