cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of a flow-streamlining implant at the distal anastomosis of a coronary artery bypass graft.

Intimal thickening in the coronary artery bypass graft (CABG) distal anastomosis has been implicated as the major cause of restenosis and long-term graft failure. Several studies point to the interplay between nonuniform hemodynamics including disturbed flows and recirculation zones, wall shear stress, and long particle residence time as possible etiologies. The hemodynamic features of two anatomic models of saphenous-vein CABGs were studied and compared. One simulated an anastomosis with both diameter and compliance mismatch and a curvature at the connection, analogous to the geometry observed in a conventional cardiothoracic procedure. The other, simulated an anastomosis with a flow stabilizing anastomotic implant connector which improves current cardiothoracic procedures by eliminating the distal vein bulging and curvature. Physiologic flow conditions were imposed on both models and qualitative analysis of the flow was performed with dye injection and a digital camera. Quantitative analysis was performed with laser Doppler velocimetry. Results showed that the presence of the bulge at the veno-arterial junction, contributed to the formation of accentuated secondary structures (helices), which progress into the flow divider and significantly affect radial velocity components at the host vessel up to four diameters downstream of the junction. The model with the implant, achieved more hemodynamically efficient conditions on the host vessel with higher mean and maximum axial velocities and lower radial velocities than the conventional model. The presence of the sinus may also affect the magnitude and shape of the shear stress at locations where intimal thickening occurs. Thus, the presence of the implant creates a more streamlined environment with more primary and less secondary flow components which may then inhibit the development of intimal thickening, restenosis, and ultimate failure of the saphenous vein graft. © 2002 Biomedical Engineering Society.
Properties of cryopreserved fetal liver stem/progenitor cells that exhibit long-term repopulation of the normal rat liver.

We have previously achieved a high level of long-term liver replacement by transplanting freshly isolated embryonic day (ED) 14 rat fetal liver stem/progenitor cells (FLSPCs). However, for most clinical applications, it will be necessary to use cryopreserved cells that can effectively repopulate the host organ. In the present study, we report the growth and gene expression properties in culture of rat FLSPCs cryopreserved for up to 20 months and the ability of cryopreserved FLSPCs to repopulate the normal adult rat liver. After thawing and placement in culture, cryopreserved FLSPCs exhibited a high proliferation rate: 49.7% Ki-67-positive on day 1 and 34.7% Ki-67-positive on day 5. The majority of cells were also positive for both α-fetoprotein and cytokeratin-19 (potentially bipotent) on day 5. More than 80% of cultured cells expressed albumin, the asialoglycoprotein receptor, and UDP-glucuronosyltransferase (unique hepatocyte-specific functions). Expression of glucose-6-phosphatase, carbamyl phosphate synthetase 1, hepatocyte nuclear factor 4α, tyrosine aminotransferase, and oncostatin M receptor mRNAs was initially negative, but all were expressed on day 5 in culture. After transplantation into the normal adult rat liver, cryopreserved FLSPCs proliferated continuously, regenerated both hepatocytes and bile ducts, and produced up to 15.1% (mean, 12.0% ± 2.0%) replacement of total liver mass at 6 months after cell transplantation. These results were obtained in a normal liver background under nonselective conditions. This study is the first to show a high level of long-term liver replacement with cryopreserved fetal liver cells, an essential requirement for future clinical applications.
Crosstalks between Cytokines and Sonic Hedgehog in Helicobacter pylori Infection: A Mathematical Model

Helicobacter pylori infection of gastric tissue results in an immune response dominated by Th1 cytokines and has also been linked with dysregulation of Sonic Hedgehog (SHH) signaling pathway in gastric tissue. However, since interactions between the cytokines and SHH during H. pylori infection are not well understood, any mechanistic understanding achieved through interpretation of the statistical analysis of experimental results in the context of currently known circuit must be carefully scrutinized. Here, we use mathematical modeling aided by restraints of experimental data to evaluate the consistency between experimental results and temporal behavior of H. pylori activated cytokine circuit model. Statistical analysis of qPCR data from uninfected and H. pylori infected wild-type and parietal cell-specific SHH knockout (PC-SHHKO) mice for day 7 and 180 indicate significant changes that suggest role of SHH in cytokine regulation. The experimentally observed changes are further investigated using a mathematical model that examines dynamic crosstalks among pro-inflammatory (IL1β, IL-12, IFNγ, MIP-2) cytokines, anti-inflammatory (IL-10) cytokines and SHH during H. pylori infection. Response analysis of the resulting model demonstrates that circuitry, as currently known, is inadequate for explaining of the experimental observations; suggesting the need for additional specific regulatory interactions. A key advantage of a computational model is the ability to propose putative circuit models for in-silico experimentation. We use this approach to propose a parsimonious model that incorporates crosstalks between NFĸB, SHH, IL-1β and IL-10, resulting in a feedback loop capable of exhibiting cyclic behavior. Separately, we show that analysis of an independent time-series GEO microarray data for IL-1β, IFNγ and IL-10 in mock and H. pylori infected mice further supports the proposed hypothesis that these cytokines may follow a cyclic trend. Predictions from the in-silico model provide useful insights for generating new hypothesis and design of subsequent experimental studies.
A comparison of two common clinical methods with high-pressure liquid chromatography for the measurement of creatinine concentrations in neonates.

The accurate measurement of low serum creatinine levels is necessary for estimating clinically useful creatinine clearances in the pediatric population. This study compares two routine clinical methods: the kinetic Jaffe with the newer Kodak enzymatic method against our reference method, high-pressure liquid chromatography, for the measurement of serum and urine creatinine levels in neonates. One hundred and twenty-five serum and 59 urine creatinines and 56 absolute creatinine clearances were measured in neonates ranging from 23 to 46 weeks (mean 32 weeks) post-conceptional age and weighing 480–4398 g (mean 1650 g). Urine creatinine levels, and serum creatinine levels greater than 0.8 mg/dl were equivalent for both clinical methods. However, the enzymatic method was much more accurate (P<0.001) than the kinetic Jaffe method for serum creatinine measurements of less than or equal to 0.8 mg/dl. We conclude that the enzymatic methodology is a better clinical choice for the accurate measurement of serum creatinine levels when using these values for the determination of neonatal renal function.
Comparison of Green-Kubo and nonequilibrium calculations of the self-diffusion constant of a Lennard-Jones fluid.

We apply the so-called ``synthetic'' nonequilibrium molecular-dynamics method to the calculation of the self-diffusion constant of a Lennard-Jones fluid at a number density of 0.85/${\ensuremath{\sigma}}^{3}$ and a temperature of 1.08\ensuremath{\varepsilon}/${k}_{B}$ (where \ensuremath{\varepsilon} and \ensuremath{\sigma} are the energy and length parameters of the potential and ${k}_{B}$ is the Boltzmann constant). By comparing with the Green-Kubo calculation for the same state of the system and for the same number of particles, N, we find the latter calculation to yield more precise values of the self-diffusion constant for a given number of molecular-dynamics time steps. Even at small values of the diffusion current, a nontrivial time is needed for the nonequilibrium calculation to reach the steady state. For larger values of the driving force, the steady-state flow appears to become unstable and evidence of a secondary flow pattern is presented. The presence of these instabilities acts as a limit to the range of the driving force for which the steady-state method can be applied. With increasing N the range of stable values of the diffusion current density decreases. For the Green-Kubo calculations, the N dependence of the self-diffusion constant is found to be anomalous for N=108, with the 1/N dependence only exhibited for at least 500 particles. The nonequilibrium results, while approximately independent of N for 108 and 500 particles, are found to have a similar anomalous N dependence when we extend the calculations to 1372 particles, thereby bringing the Green-Kubo and nonequilibrium results into agreement in the large-system limit.
Obligatory Intermolecular Electron-Transfer from FAD to FMN in Dimeric P450BM-3†

Cytochromes P450 typically catalyze the monooxygenation of hydrophobic compounds resulting in the insertion of one atom of dioxygen into the organic substrate and the reduction of the other oxygen atom to water. The two electrons required for the reaction are normally provided by another redox active protein, for example cytochrome P450 reductase (CPR) in mammalian endoplasmic reticulum membranes. P450BM-3 from Bacillus megaterium is a widely studied P450 cytochrome in which the P450 is fused naturally to a diflavin reductase homologous to CPR. From the original characterization of the enzyme by Fulco's laboratory, the enzyme was shown to have a nonlinear dependence of reaction rate on enzyme concentration. In recent experiments we observed enzyme inactivation upon dilution, and the presence of substrate can diminish this inactivation. We therefore carried out enzyme kinetics, cross-linking experiments, and molecular weight determinations that establish that the enzyme is capable of dimerizing in solution. The dimer is the predominant form at higher concentrations under most conditions and is the only form with significant activity. Further experiments selectively knocking out the activity of individual domains with site-directed mutagenesis and measuring enzyme activity in heterologous dimers establish that the electron-transfer pathway in P450BM-3 passes through both protein molecules in the dimer during a single turnover, traversing from the FAD domain of one molecule into the FMN domain of the other molecule before passing to the heme domain. Analysis of our results combined with other analyses in the literature suggests that the heme domain of either monomer may accept electrons from the reduced FMN domain.
The lower age boundaries of identity development.

ARCHER, SALLY L. The Lower Age Boundaries of Identity Development. CHILD DEVELOPMENT, 1982, 53, 1551-1556. Early and mid-adolescent males and females in the sixth, eighth, tenth, and twelfth grades were interviewed to document the lower age boundaries of ego identity development in the content areas of vocational choice, religious beliefs, political philosophies, and sex-role preferences. Frequency of the identity achievement status increased significantly with increase in grade level. The diffusion and foreclosure statuses were most evident at all grade levels. Frequency of identity status differed by content area with the majority of instances of identity achievement in the vocational choice and religious beliefs content areas, moratorium in vocational choice, foreclosure in sex-role preferences, and identity diffusion in political philosophies. Similar patterns of development were found for both sexes.
Do house prices impact business starts

Abstract At the national level, business starts and housing prices both fell dramatically over the 2007–2009 period. Using a proprietary database of business starts this paper quantitatively models the interaction between house price and business starts from 2005 to 2009. We identify the impact by exploiting the cross-sectional variation in house price changes during the period. Controlling for observable and unobservable city characteristics, we find the significance of a robust relationship between house prices and business starts depends on the size of the business starts; a robust link exists between house prices and very small business, whereas, no significant robust link is seen for large business starts.
PNS calculations for 3-D hypersonic corner flow with two turbulence models

A three-dimensional parabolized Navier-Stokes code has been used as a testbed to investigate two turbulence models, the McDonald Camarata and Bushnell Beckwith model, in the hypersonic regime. The Bushnell Beckwith form factor correction to the McDonald Camarata mixing length model has been extended to three-dimensional flow by use of an inverse averaging of the resultant length scale contributions from each wall. Two-dimensional calculations are compared with experiment for Mach 18 helium flow over a 4-deg wedge. Corner flow calculations have been performed at Mach 11.8 for a Reynolds number of .67 x 10 to the 6th, based on the duct half-width, and a freestream stagnation temperature of 1750-deg Rankine.
Laser-assisted photoemission from adsorbate-covered metal surfaces: Time-resolved core-hole relaxation dynamics from sideband profiles

Illumination of an adsorbate-covered metal surface with an xuv and a delayed ir laser pulse can result in sidebands in the photoelectron (PE) spectra. We present a theoretical model for the delay-dependent PE spectra and show how the relaxation dynamics of xuv-induced core-level holes in adsorbate atoms can be deduced from the temporal shift between sideband peaks in the spectra of secondary adsorbate (Auger) electrons and conduction-band PEs from the substrate. Furthermore, in comparison with gaseous targets, we find a characteristic sideband-intensity enhancement in the laser-assisted photoemission from the substrate core-level bands. This sideband enhancement effect can be tested in experiments with tunable xuv wavelength. Our calculated PE spectra support time-resolved experiments for Xe-covered Pt(111) surfaces, promoting the direct analysis in the time domain of surface dynamical processes.
Thrust augmentation options for the Beta 2 two-stage-to-orbit vehicle

NASA LeRC is continuing to study propulsion concepts for a horizontal takeoff and landing, fully reusable, two-stage-to-orbit vehicle. This will be capable of launching and returning a 10,000 pound payload to a 100 nautical mile polar orbit using low-risk technology. The vehicle, Beta 2, is a derivative of the USAF/Boeing Beta vehicle which was designed to deliver a 50,000 pound payload to a similar orbit. Beta 2 stages at Mach 6.5 and about 100,000 ft altitude. The propulsion system for the booster is an over/under turbine bypass engine/ramjet configuration. In this paper, several options for thrust augmentation were studied in order to improve the performance of this engine where there was a critical need. Options studies were turbine engine overspeed in the transonic region, water injection at a various turbine engine locations also during the transonic region, and water injection at the turbine engine face during high speed operation. The methodology, constraints, propulsion performance, and mission study results are presented.
Imaginary Companions in Children's Lives and Literature

(1984). Imaginary Companions in Children's Lives and Literature. Childhood Education: Vol. 60, No. 3, pp. 166-171.
User independent paging scheme for mobile IP

Multi-step paging has been widely proposed in personal communications services (PCS) systems to reduce the signaling overheads. Similar ideas can be applied to Mobile IP to provide IP paging services. However, current proposed multi-step paging schemes are user dependent under which the partition of paging areas and the selection of paging sequence are different for each user. The performance of a user dependent paging scheme for individual users may be affected by many factors. It is often difficult to achieve perfect performance for each user. In addition, when multiple users are paged at the same time, user dependent paging schemes may consume significant system resources. This paper introduces a user independent paging scheme where the paging criterion is not based on individual user information. The goal of user independent paging is to provide satisfactory overall performance of the whole system, when personalized optimal performance for each user is hard to obtain. The user independent paging scheme is proposed for IP mobility for its easy implementation and convenient combination with paging request aggregation. The paging criterion adopted is the mobility rate of each subnet determined by the aggregated movements of all mobile users. In order to implement the proposed scheme, a concept of "semi-idle state" is introduced and the detailed solution for obtaining mobility rate is presented. Analytical results show that when paging one user at a time, the performance of the proposed user independent paging scheme is comparable to that of the paging schemes based on perfect knowledge of user movement statistics. When paging multiple users simultaneously and when the knowledge on individual user behavior is not perfectly accurate, the proposed scheme has remarkable advantages in terms of reducing the overall paging cost.
Communications and business value: measuring the link

Purpose – This research examines the importance of measurement in the communications industry and business in general, the insufficiency of measurement in communications, how communications professionals' measurement needs are changing, obstacles to meeting measurement needs, and the potential benefits from understanding the link between intangibles and business value.Design/methodology/approach – Research methods used to link communications activities to business outcomes included statistical analysis (collecting, evaluating, and drawing conclusions from data) of intangible assets, or non‐accounting, non‐financial business drivers such as people, ideas and relationships. Measurement data was based on information companies already owned, including media content analysis data and employee survey results.Findings – Pilot studies have demonstrated that this model will provide greater insight into how intangibles such as communication activities contribute to business outcomes that matter to senior management...
Observational facilitation of response prevention.

Summary Facilitation of the extinction of avoidance behavior in rats were investigated by the use of prevention (flooding) and observational conditions. Rats were first trained to avoid an electric shock and then divided into 6 groups receiving various combinations of prevention (i.e. prevention vs no prevention) and observation of prevention (i.e. observation of prevention, observation of an empty shock compartment, and no observation). Treatment effects were assessed using response latency to an extinction criterion. The results indicated that response prevention is an effective facilitator of experimental extinction but is more effective when combined with observational learning.
Renormalization-group theory for the modified porous-medium equation.

We analyze the long-time behavior of the modified porous-medium equation ${\mathrm{\ensuremath{\partial}}}_{\mathit{t}}$u=D\ensuremath{\Delta}${\mathit{u}}^{1+\mathit{n}}$ in d dimensions, where n is arbitrary and D=1 for ${\mathrm{\ensuremath{\partial}}}_{\mathit{t}}$ug0 and D=1+\ensuremath{\epsilon} for ${\mathrm{\ensuremath{\partial}}}_{\mathit{t}}$u0. This equation describes inter alia the height of a groundwater mound during gravity-driven flow in porous media (d=2, n=1) and the propagation of strong thermal waves following an intense explosion (d=3, n=5). Using general renormalization-group (RG) arguments, we show that a radially symmetric mound exists of the form u(r,t)\ensuremath{\sim}${\mathit{t}}^{\mathrm{\ensuremath{-}}(\mathit{d}\mathrm{\ensuremath{\theta}}+\mathrm{\ensuremath{\alpha}})}$f(${\mathit{rt}}^{\mathrm{\ensuremath{-}}(\mathrm{\ensuremath{\theta}}+\mathrm{\ensuremath{\beta}})}$, \ensuremath{\epsilon}), where \ensuremath{\theta}==1/(2+nd) and \ensuremath{\alpha} and \ensuremath{\beta} are \ensuremath{\epsilon}-dependent anomalous dimensions, obeying the scaling law n\ensuremath{\theta}\ensuremath{\alpha}+(1-nd\ensuremath{\theta})\ensuremath{\beta}=0. We calculate \ensuremath{\alpha} and \ensuremath{\beta} to O(\ensuremath{\epsilon}), for general d and n, using a perturbative RG scheme. In the case of groundwater spreading, our results to O(${\mathrm{\ensuremath{\epsilon}}}^{2}$) are in good agreement with numerical calculations, with a relative error in the anomalous dimension \ensuremath{\alpha} of about 3% when \ensuremath{\epsilon} is 0.5.
Binding energies of λλ hypernuclei and the λλ interaction

Abstract The binding energies of the ΛΛ hypernuclei 10ΛΛBe and 6ΛΛHe are calculated variationally with a 2α + 2Λ and with an α + 2Λ model, respectively. For 10ΛΛBe the integrations were made with Monte Carlo techniques while for 6ΛΛHe direct numerical methods were used. A wide range of phenomenological ΛΛ potentials based on meson-exchange models was considered. An approximately universal linear relation between the calculated values of B ΛΛ ( 10 ΛΛ Be ) and of B ΛΛ ( 6 ΛΛ He ) is obtained. For the experimental value of B ΛΛ ( 10 ΛΛ Be ) = 17.7 ± 0.1 MeV this relation predicts a much too small value of B ΛΛ ( 6 ΛΛ He ) , well below the lower limit of the quoted experimental value of 10.9 ± 0.6 MeV. For ΛΛ potentials with repulsive cores the relations, for a given B ΛΛ ( 10 ΛΛ Be ) , between the low-energy ΛΛ scattering parameters a, r0 and the intrinsic range b are both approximately universal and independent of the detailed potential shape. For the experimental value of B ΛΛ ( 10 ΛΛ Be ) the preferred values are 2.5 ≲ −a ≲ 3.5 fm, 2.6 ≲ r0 ≲ 3.1 fm. The large and negative values of a correspond to conditions not too far from a bound 1S0 ΛΛ state and could indicate a 6-quark dibaryon state with the same quantum numbers and above the ΛΛ threshold.
The Genesis of Neurosurgery and the Evolution of the Neurosurgical Operative Environment: Part I—Prehistory to 2003

Despite its singular importance, little attention has been given to the neurosurgical operative environment in the scientific and medical literature. This article focuses attention on the development of neurosurgery and the parallel emergence of its operative setting. The operative environment has, to a large extent, defined the "state of the art and science" of neurosurgery, which is now undergoing rapid reinvention. During the course of its initial invention, major milestones in the development of neurosurgery have included the definition of anatomy, consolidation of a scientific basis, and incorporation of the practicalities of anesthesia and antisepsis and later operative technical adjuvants for further refinement of action and minimalism. The progress, previously long and laborious in emergence, is currently undergoing rapid evolution. Throughout its evolution, the discipline has assimilated the most effective tools of modernity into the operative environment, leading eventually to the entity known as the operating room. In the decades leading to the present, progressive minimalization of manipulation and the emergence of more refined operative definition with increasing precision are evident, with concurrent miniaturization of attendant computerized support systems, sensors, robotic interfaces, and imaging devices. These developments over time have led to the invention of neurosurgery and the establishment of the current state-of-the-art neurosurgical operating room as we understand it, and indeed, to a broader definition of the entity itself. To remain current, each neurosurgeon should periodically reconsider his or her personal operative environment and its functional design with reference to modernity of practice as currently defined.
Continuous Culture Studies on the Growth and Physiology of Streptococcus mutans

We examined the effects of nutritional limitations on the production of lactic acid by Streptococcus mutans grown at low growth rates in continuous culture. Lactic acid production was greater in nitrogen- and phosphate-limited continuous cultures than in glucose-limited conditions. These results are correlated with the release of calcium from enamel in cellfree broths from various fermentations.
Animal models for complement deficiencies

The complement system plays a key role in host defense and in the development of autoimmunity. Three types of animal models of complement-mediated disease have traditionally been used: they involve normal animals, animals with spontaneously arising genetic deficiency, and animals treated with complement-inactivating agents. All of these approaches have had partial success in our attempts to understand complement mechanisms. Most animal models of genetic deficiency have been studied relatively little, as the availability of such animals is limited. C4, C2, and partial C3 deficiency in the guinea pig are well characterized, although only C4 deficiency in the guinea pig has been exclusively studied. C3 deficiency in the dog and C6 deficiency in the rabbit are well described, although studies are limited in number. C6 deficiency in the rat has been described recently and C5 deficiency in inbred mice strains has been studied fairly extensively. Factor H deficiency in the Yorkshire pig has also been described. Relatively few agents that inhibit complement are in use. Most widely used in animal studies is cobra venom factor. This inactivates the alternative complement pathway in the fluid phase and thereby depletes complement protein levels. The antigenicity of this protein, purified from the venom of cobras, limits its duration of use in most animal models. Complement-inhibiting agents are rare and, as yet, not widely used. We recently described the use of intravenous immune globulin for inhibiting complement in animal studies and present data on its use in animals, including discordant xenograft rejection, and its potential use in human disease. New developments in molecular biology provide the potential for a vast new array of deficiency models. A limited number of laboratories are actively engaged in the production of animals with inactivated genes. For example, gene knockout mice with no C3, and with no factor B, have been generated. Several complement control proteins have been prepared by genetic molecular biological techniques. Most promising among these is CR1, which limits complement damage in several animal models. Transgenic animals, with complement regulatory proteins expressed on their cells, have been prepared. As complement control proteins tend to be more efficient at regulating complement of the same species type as the regulatory protein, these animals may be useful in such areas as xenograft transplantation. The various animal models are reviewed and their potential application to understanding of human disease is emphasized.
Proflavin mutagenesis of bacteria.

Abstract Once a permeability barrier is overcome, proflavin is highly mutagenic for Salmonella typhimurium and Escherichia coli. Mutagenesis of the his operon (in Salmonella) and lac operon (in E. coli) depends on derepression of the respective operons. No proflavin mutagenesis was detected in rec− strains. Over 100 proflavin-induced his mutants have been classified: 50% are base substitution types, 30% are stable (10% demonstrably multisite), and only 20% are probably frameshift mutations. None of the proflavin-induced frameshift mutations is of the type previously shown to be suppressed by frameshift suppressor mutations.
CLASS, GENDER, AND ARREST: AN INTERGENERATIONAL ANALYSIS OF WORKPLACE POWER AND CONTROL*

Power-control theory posits that parental workplace positions affect adolescent law violation. To date, however, no test of the theory has directly measured occupational power and control. This paper tests whether parental and adolescent workplace freedom and control affect criminal behavior and arrest as the theory predicts, using data from a prospective longitudinal survey of 1, 000 adolescents and their parents. The results suggest sex differentials in the effects of maternal authority position and parental freedom and control. In particular, daughters whose mothers hold authority positions are more likely to be arrested than are daughters whose mothers do not hold such positions. The effects of adolescent employment also differ by sex, with perceived workplace power and control reducing rates of arrest among females but increasing them among males.
Algorithms for determining equilibrium points in multistage voting games

Voting schemes are expressed as N person, single or multistage games in extensive form with ordinal preferences. Some of the voters can be indifferent to certain outcomes. The voters are not allowed to consult one another before arriving at the result. A majority rule with tie breaking is used. The voting schemes are labelled as binary or nonbinary depending on whether the number of alternatives in every ballot is two or more than two. We prove the principle of optimality for the voting problems and hence derive an algorithm for determining all the Nash strategies in which the voters restrict themselves to admissible strategies and the corresponding Nash values. In N stage binary games with strict preferences there is a unique Nash value which can be realized if a majority of the players vote according to the Nash strategy. Finally the Nash equilibrium strategies derived here have the important property that if the voters vote according to a Nash strategy, then they obtain an outcome which is often more favourable to the majority than an outcome obtained by other game strategies like the straightforward strategies. It is very rare that the Nash strategy will yield an outcome which is the least preferred outcome for any majority of voters.
General and Special Educators' Predictions of Student Success as a Function of Learner Characteristics and Teacher Experience:

This study compared the influence of teacher and learner characteristics on general and special educators' predictions of student success. Two groups of teachers, 384 general educators and 384 special educators, reported year of experience and responded to case studies describing a student for whom gender, reading achievement, social behavior, and attentiveness were manipulated experimentally. Results indicated (a) when predicting academic success, general educators make lower predictions than special educators as a function of students' reading achievement; (b) when predicting social success, teachers respond differently as a function of students' behaviors as they interact with reading achievement; and (c) compared to novice teachers, experienced teachers make more positive predictions of social success regarding both aggressive and friendly students. The authors discuss the complexity of the interactions of teachers' and students' characteristics and their implications for the classroom.
Infection of the conjunctiva by Rhinosporidium seeberi.

Abstract Rhinosporidiosis is an unusual fungal disease that rarely affects the eye. It was first described as a pathogen in humans at the turn of the century. The etiologic agent, Rhinosporidium seeberi , commonly produces granulomatous inflammation of the upper respiratory mucosa. Most reproted ocular infections have occurred in hot, dry climatic regions. We present a case of conjunctival rhinosporidiosis in an 11-year-old boy from western New York state, the first such report from the temperate zones of North America. The clinical characteristics, histopathologic features, and recommended therapeutic measures are discussed.
A Critical Evaluation of Gel Chromatography

Abstract Gel chromatography includes a number of related techniques for separating molecules by means of solvent-swollen gels. The gels consist of three-dimensional networks of cross-linked polymeric chains of controlled porosities which exclude molecules from the interior of the gel to a degree depending on relative dimensions of molecule and pore. Current theories relating the elution volume to a partition coefficient or to molecular properties are discussed. A general equation has not yet been proposed. Such an equation would necessarily include the three important mechanisms: exclusion, restricted diffusion, and adsorption.
NEW SPECTROSCOPIC TECHNIQUES FOR STUDYING THE ORIGIN OF MOLECULAR PHOSPHORESCENCE.

Abstract At temperature for which the electron spin-lattice relaxation times between the zero-field levels of the lowest triplet state are comparable to or longer than the phosphorescence lifetimes, the relative intensity of the different vibronic bands in the phosphorescence spectrum and the observed decays are sensitive to changes in temperature, application of magnetic fields, and saturation of the triplet state zero-field transitions with microwave radiation. From the changes in the spectrum and in the decays upon applying these perturbations, the zero-field level(s) responsible for the intensity of each vibronic band can be determined, as well as the complete description of the spin-orbit coupling scheme.
Early coronary graft thrombosis following surgery for Prinzmetal's angina: treatment with nifedipine and thrombolysis.

REFERENCES 1. McDonald A, Harris A, Jetterson K, Marshall J, McDonald L: Association of prolapse of posterior cusp of mitral valve and atrial septal defect. Br Heart J 33:383, 1971. 2. Pocock WA, Barlow JB: An association between billowing posterior mitral leaflet syndrome and congenital heart disease, particularly atrial septal defect. AM HEART J 81:720, 1971. 3. Jeresaty RM: Atrial septal defect and myxomatous mitralvalve prolapse. N Engl J Med 290:1088, 1974. 4. Leachman RD, Cokkinos DV, Cooley DA: Association of ostium secundum atrial septal defects with mitral valve prolapse. Am J Cardiol 38:167, 1976. 5. Rippe JM, Sloss LJ, Angoff G, Alpert JS: Mitral valve prolapse in adults with congenital heart disease. AM HEART J 97:561, 1979.
Penetration-depth anisotropy in unconventional superconductors.

We consider the superfluid density tensor in a three-dimensional superconductor, as a function of temperature and impurity concentration. We compare the results for two different order parameters: an anisotropic {ital s}-wave gap {Delta}{sub {ital s}}(@k{cflx R}), and a {ital d}-wave gap {Delta}{sub {ital d}}(@k{cflx R}) with {Delta}{sub {ital s}}(@k{cflx R})={vert_bar}{Delta}{sub {ital d}}(@k{cflx R}){vert_bar}. While the two order parameters yield identical {rho}(spec. char. missing) tensors in the pure limit, we find that the addition of impurities affects the two cases very differently. In particular, the behavior of the anisotropy distinguishes the two order parameters. Thus measurements of the anisotropy as a function of impurity concentration can be a key to identifying the order-parameter symmetry. We also discover a surprising result: the addition of impurities can increase one of the principal values of {rho}(spec. char. missing){sub {ital s}}, in the {ital s}-wave case.
Statistical estimation of resistance/conductance by electrical impedance tomography measurements

This paper is built upon the assumption that in electrical impedance tomography, vectors of voltages and currents are linearly dependent through a resistance matrix. This linear relationship was confirmed experimentally and may be derived analytically under certain assumptions regarding electrodes (Isaacson, 1991). Given measurement data consisting of voltages and currents, we treat this relationship as a linear statistical model. Thus, our goal is not to reconstruct the image but directly estimate its electromagnetic properties reflected in the resistance and/or conductance matrix using electrical impedance tomography (EIT) measurements of voltages and currents on the periphery of the body. Since no inverse problem is involved the algorithm for estimation merely reduces to one matrix inversion. We estimate the impedance resistance matrix using well established statistical inference techniques for linear regression models. We provide a comprehensive treatment for a two-dimensional homogeneous body of a circular shape, by which many concepts of electrical impedance tomography, such as width of electrodes, the difference between voltage-current and current-voltage systems are illustrated. Our theory may be applied to various tests including EIT hardware calibration and whether the medium is homogeneous. These tests are illustrated on phantom agar data.
Recent advances in the neuropsychology of Alzheimer's disease.

Abstract 1. Memory, language, and visuospatial impairments are prominent neuropsychological deficits in Alzheirner's disease. 2. The neuropsychological characteristics of Alzheimer's disease are unigue, and contrast with those of other brain diseases. 3. Neuropsychological study of patients with Alzheimer's disease may he useful in discovering the neuronal basis of cognitive processes, in differential diagnosis of dementia, and in evaluating treatment.
Magnesium-25 Hyperfine Confirmation of the Localized-Ground-State Model of the V − Center in MgO

The localized-hole model of the ${V}^{\ensuremath{-}}$ center in the alkaline earth oxides is represented as a positive hole trapped on one oxygen atom adjacent to a positive-ion vacancy (in the ground state and on the time scale of an ESR experiment). Upon trapping the hole, the oxygen atom is presumed to relax away from the vacancy, thus lowering the symmetry from octahedral to tetragonal. The validity of this model has recently been challenged on the basis that a proper description of the ground state is a molecular orbital representing a linear combination of states with the hole on either of the two oxygen atoms opposite one another about the vacancy. We present the analysis of some ESR spectra in which we observed the resolved hyperfine splitting due to a single $^{25}\mathrm{Mg}^{2+}$ ion adjacent to the trapped hole and on the axis of the defect. From the natural abundance of the $^{25}\mathrm{Mg}$ isotope one can calculate the expected hyperfine line intensities relative to that of the central line arising from ${V}^{\ensuremath{-}}$ centers having only $^{24}\mathrm{Mg}$ or $^{26}\mathrm{Mg}$ atoms in the axial positions, for the localized and for the delocalized models. The measured relative intensities agree with those calculated for the localized model. An analysis of the axial spectrum indicates the presence of an unusually intense forbidden line at $X$ band. This becomes relatively more intense at the $\mathrm{Ku}$ band, as expected. Shifts of line position and intensity relative to the lines of an allowed hyperfine sextet agree with those predicted. The values of the hyperfine parameters are found to be $A=+2.84$ MHz and $B=\ensuremath{-}0.86$ MHz. The quadrupole parameter is found to be +0.18 MHz. The sign of $A$ is anomalous in that a contact interaction is expected to give an isotropic parameter with the sign of the nuclear magnetic moment. This may result from exchange polarization. The magnitude of $B$ is interpreted as indicating a compact unpaired charge distribution. The ${V}^{\ensuremath{-}}$ centers studied here were generated by fast-neutron irradiation, and there is no confusion with impurity-associated hole centers; the former have a long-term stability in MgO, while the latter decay rapidly to negligible levels at room temperature.
Analysis of corpora of variations

IN THE EDITING of critical texts, there are three major steps that seem to lend themselves especially well to computer assistance: collation, analysis of the corpus of variations produced by collation, and the editing and proofreading of the various textual versions and of the final critical text. There has been a great amount of work done with the first step collation. Best known probably are Vinton A. Dearing's work with Dryden, George Petty and William Gibson's OCCULT programs, and R. L. Widmann's edition of Midsummer Night's Dream.' Such projects, though they required a great deal of work to perfect, have been generally thought to serve a very useful purpose and to save much time-consuming labor once they were perfected.
Androgen Abuse by Athletes

Introduction ANDROGEN abuse by athletes constitutes only a portion of the problem of androgen misuse by the general population (1) and only a minor aspect of the doping of athletes with drugs presumed to enhance athletic ability (2, 3). Indeed, of the drugs banned by the International Olympic Committee, steroids account only for about 15% (4). This particular form of drug abuse stems from the convergence of several separate misconceptions. The first was the recognition that the administration of androgens to hypogonadal males causes an increase in nitrogen retention and an increase in muscle mass and lean body weight (5). It followed that the differences in muscle mass between men and women are largely due to differences in testosterone levels, and it was assumed that the administration of androgens in supraphysiological amounts to normal men would do even more than the normal amount. The second misconception was that the anabolic (muscle promoting) and androgenic (virilizing) actions of the hormone are e...
Prophylactic β‐blocker therapy: Clinical implications of an aggregate analysis

Background. The value of beta-adrenergic-antagonist drug therapy for the prevention of initial episodes of gastrointestinal bleeding in patients with cirrhosis and esophageal varices is uncertain, both positive and negative study results having been reported. Methods. In this study, we analyzed data on individual patients from four randomized, controlled trials to assess the efficacy of this treatment. Of the 589 patients studied, 286 received a beta-adrenergic-antagonist drug (propranolol in 203 and nadolol in 83) and 303 received placebo. Results. After two years, the mean (± SE) percentage of patients who had had no upper gastrointestinal bleeding was 78 ± 3 percent in the beta-adrenergic-antagonist treatment group and 65 ± 3 percent in the control group (P = 0.002). The percentage of patients without fatal bleeding was 90 ± 2 percent in the treatment group and 82 ± 3 percent in the control group (P = 0.01). The percentage of patients surviving after two years was 71 ± 3 percent in the treatment group and 68 ± 3 percent in the control group (P = 0.34). After age and severity of cirrhosis were taken into account, the survival rate was better in the treatment group (P = 0.09). The percentage of surviving patients who had had no bleeding after two years was 62 ± 3 percent in the treatment group and 53 ± 3 percent in the control group (P = 0.04). Both propranolol and nadolol prevented a first episode of bleeding. Severe cirrhosis and especially the presence of ascites were associated with bleeding (P < 0.001) and death (P < 0.001) in both groups. The efficacy of beta-adrenergic-antagonist therapy in the prevention of bleeding (P < 0.001) and of fatal bleeding (P = 0.004) and in the prevention of bleeding or death (P = 0.005) was the same after adjustment for cause and severity of cirrhosis, ascites, and size of varices. Conclusions. Propranolol and nadolol are effective in preventing first bleeding and reducing the mortality rate associated with gastrointestinal bleeding in patients with cirrhosis, regardless of severity.
Facile, rapid, and large-area periodic patterning of semiconductor substrates with submicron inorganic structures.

The development of high-throughput and scalable techniques for patterning inorganic structures is useful for the improved function and efficiency of photonic and energy conversion devices. Here we demonstrate a facile and rapid electrochemical method for patterning periodic metallic and nonmetallic submicron structures over large areas. Si substrates have been patterned with arrays of periodically spaced lines, rings, squares, and terraces of main-group and transition-metal oxides. In addition to planar substrates, three-dimensional surfaces and their vertical sidewalls have been patterned. The features are 20(±1) nm high and 360(±15) nm wide, and their period is finely tunable in situ from 500 nm to 7 μm. These features exhibit <3% variation in period and are rapidly patterned in <2 min. We demonstrate the versatility of the technique by rapidly patterning an efficient water splitting catalyst, Co phosphate oxide (CoPi), and show that the integrated materials system performs water splitting with complete...
Cost-Benefit Analysis as a Statistical Hypothesis Test: An Example from Urban Transportation

A method to evaluate the estimated social benefits and costs of many urban transportation decisions is presented, based on the techniques of statistical hypothesis testing. After a slight critique of current practice in cost-benefit analyses, a general equilibrium model is formulated that includes many of the relevant variables and decisions which interact with an urban transportation system. The model is based on individual behavior assumptions (as opposed to macro-behavior) and uses the concept that commodities provide attributes. The significant omissions are mentioned and discussed. It is next shown that if the model is true, then hypotheses involving the Pareto-superiority (and Pareto-optimality) of various decisions with respect to transportation systems imply hypotheses restricting the values of parameters of a single linear equation. This allows the testing (i.e. falsification) of the original hypotheses by using the familiar T and F tests of regression analysis. These tests are based on a single-...
Translocations as a Tool for Restoring Populations of Bighorn Sheep

We analyzed factors that contributed to the success of 100 translocations of bighorn sheep within six western states between 1923 and 1997. We categorized the populations as unsuccessful (i.e., extirpated or remnant, , 29 animals), moderately successful (30‐99 animals), and successful (100‐350 animals) by the end of the study period in 1997. Thirty of the translocated populations were unsuccessful ( n 5 13 were extirpated and n 5 17 were remnant), 29 were moderately successful, and 41 were successful (21 6 1.3 [SE] years of information per translocation). Translocations were less successful when domestic sheep were located within 6 km of the known bighorn sheep use areas (logistic regression, p 5 0.052). Grazing of cattle on the same range also negatively influenced success ( p 5 0.004). Use of indigenous versus previously translocated source stocks increased success ( p 5 0.084). The translocation was twice as likely to be successful when indigenous herds were used as sources ( p 5 0.043), but mixing genetic stocks ( p 5 0.381) or later additional augmentations did not influence success ( p 5 0.095). Annual migrations by newly established translocated populations increased success ( p 5 0.014). We recommend translocations of founder groups of bighorn sheep from indigenous
Demonstration of Basic Geometric Rotations on Rare-Earth Atomic Ensemble

Two basic Bloch vector rotations on a rare-earth ensemble were demonstrated through geometric paths driven by composite laser pulses, which can be used to compose any single qubit gate. The operation fidelity was evaluated.
Utility of Screening for Chronic Granulomatous Disease in Patients with Inflammatory Bowel Disease

Chronic granulomatous disease (CGD), a genetically heterogeneous primary X-linked or autosomal recessive immunodeficiency, can manifest with gastrointestinal symptoms, including colitis or Crohn's disease. The frequency of CGD carriers among those with chronic colitis/inflammatory bowel disease is unknown. We underwent a pilot study examining the value of prospectively screening patients with chronic colitis/inflammatory bowel disease (IBD) for either CGD or the carrier state of CGD. No carriers of CGD or patients with CGD were detected among 120 patients. Three patients had inconclusive results and the assay was normal on repeat testing. We conclude that routine screening for CGD was not instructive in this cohort of chronic colitis or IBD patients.