cssi/SciSciGPT-SciSciNet huggingface dataset:
Observed precursor of pulsed radio waves

as well as in a waveguide, indicate that the precursor or the very earlwavefront onset, slightly above the noise level, propagates with a speed equato the phase velocity. Since it is observable, it may be useful for radiomessages. Basic principles and experimental support are presented.1. INTRODUCTIONFor a monochromatic uniform TEM plane wave propagating in free space, thegroup velocity is equal to the phase velocity [1], [2]. Under the samecondition amplitude modulated signals can be characterized by means of a frontand a signal velocity [1], [3], [4]. When the direction of propagation of thewaves coincide with a direction in which an observer is interested, the phasevelocity and the front velocity is equal to the intrinsic velocity of the wavesin free space [3], [4]. When the observer is interested in a directiondifferent from the prefixed direction of propagation of the same wave, theconcept of apparent or phenomenal velocity becomes meaningful [5]-[8], [9],
Anti-CD30 antibody–based therapy

The increased expression of CD30 on some neoplasms versus its limited expression on normal tissue makes it an excellent target for antibody-based therapy. Recent studies have shown that anti-CD30 antibodies may serve as signaling molecules as well as mediators of interactions with the immune system.
Molecular Cloning and Expression Pattern of Porcine Myeloid DAP12-Associating Lectin-1

Abstract DAP12 is an ITAM-bearing membrane protein that is associated with activating receptors in natural killer cells, granulocytes, macrophages, and monocytes. Myeloid DAP12-associating lectin-1 (MDL-1) is a type II membrane protein that associates with DAP12. In this study, we report the molecular cloning of two isoforms of porcine MDL-1 cDNA from pulmonary alveolar macrophages. The porcine MDL-1 short form has 165 amino acids and 70% sequence identity with the mouse MDL-1 short form. The long form has 20 more amino acids in the stalk region and 71% sequence identity with human MDL-1 and 67% with the mouse MDL-1 long form. Porcine MDL-1 contains a conserved lysine in the transmembrane domain. There are six putative N-linked glycosylation sites in the MDL-1 long form. MDL-1 transcripts were detected exclusively in macrophages and monocytes by RT–PCR. When transfected into 293 cells, porcine MDL-1 is expressed on the cell surface associated with DAP12.
Expression of a peroxiredoxin-glutaredoxin by Haemophilus influenzae in biofilms and during human respiratory tract infection.

Evidence is mounting that nontypeable Haemophilus influenzae grows as a biofilm in the middle ear of children with otitis media and the airways of adults with chronic obstructive pulmonary disease. To begin to assess antigens expressed by H. influenzae in biofilms, cell envelopes of bacteria grown as a biofilm were compared to those grown planktonically. A ∼30 kDa peroxiredoxin–glutaredoxin was present in greater abundance during growth in biofilms. Mutants deficient in expression of peroxiredoxin–glutaredoxin were constructed by homologous recombination in four clinical isolates. The mutants showed a 25–50% reduction in biofilm formation compared to the corresponding parent strains. To study in vivo expression of peroxiredoxin–glutaredoxin during human respiratory tract infection, paired pre- and post-exacerbation serum from adults with chronic obstructive pulmonary disease and H. influenzae in sputum were assayed using an enzyme-linked immunosorbent assay and purified recombinant peroxiredoxin–glutaredoxin. Eight from 18 (44.4%) paired serum samples showed a significant increase in antibody to peroxiredoxin–glutaredoxin from pre- to post-infection. These results indicate that (1) peroxiredoxin–glutaredoxin is present in greater abundance in H. influenzae biofilms compared to planktonically grown bacteria; (2) peroxiredoxin–glutaredoxin is involved in biofilm formation by H. influenzae and the degree of involvement varies among strains; and (3) peroxiredoxin–glutaredoxin is expressed by H. influenzae during infection of the human respiratory tract and is recognized by the human immune system.
Spatiotemporal expression patterns of mammalian chordin during postgastrulation embryogenesis and in postnatal brain

Chordin is an antagonist of TGFβ-like bone morphogenetic proteins (BMPs) that plays roles in dorsoventral axis formation and in induction, maintenance and/or differentiation of neural tissue in early vertebrate embryogenesis. In contrast, little is known concerning possible roles for Chordin at later stages of vertebrate development and in the adult. To provide insights into possible postgastrulation roles for Chordin, we report the spatiotemporal expression patterns of Chordin in 8.5- to 15.5-dpc mouse embryos and in the postnatal mouse brain. Expression of Chordin in the primordia of most major organs from 10.5 dpc, including the brain, lung, heart, liver, kidney, thymus, and gut, suggests multiple functions for Chordin in organogenesis, potentially by means of interactions with TGFβ-like BMPs. The relatively high levels of Chordin expression in condensing and differentiating cartilage elements from 11.5 dpc indicates a generalized role for Chordin throughout embryonic skeletogenesis. In the postnatal mouse brain, we demonstrate that Chordin is coexpressed with other components of the TGFβ-like BMP signalling pathway in the cerebellum and hippocampus, sites of high synaptic plasticity, suggesting a role for Chordin in this process. Dev Den;217:449–456. © 2000 Wiley-Liss, Inc.
Epidemiology of particulate air pollution: exploiting observable exposure variability

Epidemiological studies of PM pollution and health have attempted to exploit observable sources of exposure variability to evaluate potential health consequences. These studies have become increasingly ingenious and rigorous in their ability to use natural exposure variability. Although a large majority of studies have evaluated only changes in short-term exposures, long-term, chronic exposure may be more important in terms of overall public health. This paper outlines the various dimensions of natural PM exposure variability that have been exploited in the epidemiology of PM literature, discuss how this exposure variablilty has or has not been utilized in recent epidemiology studies of PM exposure and human health, outline the inferences being drawn from the studies, and present the major limitations of these studies.Copyright © 1999 John Wiley & Sons, Ltd.
Effects of amiodarone on supraventricular tachycardia involving bypass tracts

This study evaluates whether the electrophysiologic effects of i.v. amiodarone in patients with reentrant supraventricular tachycardia (SVT) can predict the efficacy of long-term oral therapy with this drug. The effects of oral and i.v. amiodarone were studied in 27 patients with SVT. In 14 the SVT circuit involved a concealed atrioventricular bypass for retrograde conduction (Group I), and in 13 a concealed atrio-His bypass (Group II). Intravenous amiodarone induced significant prolongation of the AH interval, the refractory periods of the atrium, atrioventricular node, His-Purkinje system and ventricular myocardium. The ventriculoatrial interval was slightly prolonged in Group I patients and did not change in Group II patients after i.v. administration of the drug. In both groups, the effective refractory period (ERP) of the concealed bypass was prolonged by i.v. amiodarone. During control state, SVT could be induced in all patients; after i.v. administration of the drug, SVT was presented in 6 patients in Group I and in 8 patients in Group II. In all cases, in which i.v. amiodarone prolonged the ERP of the concealed bypass to more than 350 ms, the drug always prevented SVT even when given orally. All but 2 patients--1 from Group I and 1 from Group II--remained asymptomatic after oral amiodarone. In the patient from Group I, SVT had been prevented by i.v. amiodarone, whereas in the patient from Group II SVT could not be induced by ventricular stimulation during the control state, but appeared after i.v. administration of the drug.(ABSTRACT TRUNCATED AT 250 WORDS)
Gene–environment-wide association studies: emerging approaches

Despite the yield of recent genome-wide association (GWA) studies, the identified variants explain only a small proportion of the heritability of most complex diseases. This unexplained heritability could be partly due to gene--environment (G×E) interactions or more complex pathways involving multiple genes and exposures. This Review provides a tutorial on the available epidemiological designs and statistical analysis approaches for studying specific G×E interactions and choosing the most appropriate methods. I discuss the approaches that are being developed for studying entire pathways and available techniques for mining interactions in GWA data. I also explore methods for marrying hypothesis-driven pathway-based approaches with 'agnostic' GWA studies.
Acetylenyl-Linked, Porphyrin-Bridged, Donor−Acceptor Molecules: A Theoretical Analysis of the Molecular First Hyperpolarizability in Highly Conjugated Push−Pull Chromophore Structures

We describe the theoretical basis for the exceptionally large molecular first hyperpolarizabilities inherent to (5,15-diethynylporphinato)metal-bridged donor−acceptor (D−A) molecules. β values relevant for hyper-Rayleigh experiments are calculated at 1.064 and 0.830 μm for a complex with such a structure, [5-((4‘-(dimethylamino)phenyl)ethynyl)-15-((4‘‘-nitrophenyl)ethynyl)-10,20-diphenylporphinato]zinc(II), and are 472 × 10-30 and 8152 × 10-30 cm5/esu, respectively. The values are 1 order of magnitude larger than that calculated for any other porphyrin bridged donor−acceptor chromophore studied to date. The considerably enhanced hyperpolarizability arises from the significant excited-state electronic asymmetry manifest in such structures (derived from the strong bridge-mediated D−A coupling enabled by the largely porphyrin-based excited state) and the large bridge-centered oscillator strength in this new class of D−bridge−A molecules. Our analysis of NLO properties (based upon INDO/SCI calculations within...
Getting to the Heart of the Matter: Epidemiology of Cyanotic Heart Defects

Congenital heart defects (CHDs) are the most common type of birth defect, making significant contributions to infant morbidity and mortality, but not all CHDs contribute equally to such outcomes. Although cyanotic CHDs constitute some of the most serious CHDs, its epidemiology is poorly understood. We present a comprehensive systematic review of the literature on the epidemiology of cyanotic CHD, with emphasis on the most current knowledge on identified risk/etiologic factors. Literature for this review was identified by searching the PubMed database from the National Center for Biotechnology Information at the US National Library of Medicine as well as bibliographies of identified papers. The 100 reports that contributed to this review describe risk factors such as infant sex, race, and ethnicity, environmental exposures, and maternal and paternal age. Several studies reported differences in prevalence rates by race and ethnicity and elevated sex ratios, and they identified some risk factors, including advanced maternal age. Investigators have made significant progress in the effort to describe the etiology of cyanotic CHDs, but discrepancies, such as the variation in prevalence rates by race and ethnicity and the impact of environmental exposures, still need to be addressed.
Mars - Paleostratigraphic restoration of buried surfaces in Tharsis montes

Volcanism in the Tharsis province of Mars occurred in several different areas and was generally continuous without large time intervals between eruptive episodes. Major lava flow units are numerous and extensive, but relatively thin. In many places, impact craters on buried surfaces project above younger flows that overlie them. A new application of crater dating methods has been developed to aid in the identification of these buried surfaces and to determine their lateral extent. The technique is especially adaptable to the Tharsis region where the stratigraphic succession of major flow units has been established by detailed geologic mapping. Knowledge of the overall stratigraphy allows correlations to be made between known and unknown surfaces by comparing their crater frequencies at diameters large enough to insure their recognition on the buried unit. The method has been applied to aid in the restoration of buried rock units and to construct a series of paleostratigraphic maps showing the sequence of major eruptive events in the Tharsis region.
Kinetic amplification of enzyme discrimination.

Summary The dependance of the accuracy of enzymatic systems on the mechanism of the catalyzed reaction is investigated, using a probabilistic approach. Certain mechanisms of reaction, involving a delay in one of the steps act as kinetic amplifiers of molecular discriminations. The relationship between our scheme for a delayed reaction [1] and Hopfield's scheme [2] is discussed.
Quantum chemistry by random walk: Method of successive corrections

Abstract The random-walk method of solving the Schrodinger equation is reformulated to allow the direct calculation of the difference δ between a true wavefunction ψ and a trial wave-function ψ 0 . For a trial wavefunction from any source the difference δ may be calculated and used to correct the trial wavefunction. Successive calculations offer the possibility of further corrections and wavefunctions of unlimited accuracy. The calculation of δ is illustrated for the cases of the particle-in-a-box and the hydrogen atom. Energies are determined directly from the random-walk calculations and indirectly from computation of the expectation values for the corrected wavefunctions.
Cryptic receptors for chemotactic peptides in rabbit neutrophils.

Abstract Specific binding of chemotactic peptides to receptors in rabbit neutrophils was enhanced in the presence of aliphatic alcohols — especially n-propanol and n-butanol. The effect was concentration dependent with maximum increases in specific binding of 2.6 and 3.0 fold in the presence of 2.5% n-propanol and n-butanol respectively. The results indicate that up to 65% of the receptors are cryptic and unavailable for ligand interactions. It is suggested that minute to minute modulation of chemotactic responsiveness could occur by controlling at the membrane level the number of receptors exposed to chemotactic stimuli.
Sexual productivity and spring intramarsh distribution of a key salt-marsh microbial secondary producer

Phaeosphaeria spartinicola is known to be an important fungal (ascomycetous) secondary producer in the smooth-cordgrass (Spartina alterniflora) decomposition system of western Atlantic salt marshes, yet its degree of predominance among the ascomycete assemblages of salt marshes and the concentration of its sexual reproductive structures (ascomata) have been largely unknown. During May–June, we measured by direct microscopy the percent occupancy of leaf abaxial area and concentrations of ascomata in leaf blades of smooth cordgrass at three elevations in three drainage systems within the marshes of Sapelo Island, Georgia, United States. We also measured in water-saturation chambers the rates at which the ascomata expelled ascopoores (sexual propagules) out of decaying leaves from marsh sites containing or not containing shredder gastropods.P. spartinicola ascomata were found at averages of 36% to 93% of grid-circles (3-mm radius) on decaying leaf blades, with lower values at points directly adjacent to the leaf sheath, on leaves at earlier stages of decay, and at elevational subsites where shredder snails were more active. Marsh elevation had no effect of its own on percent occupation. No other species of ascomycetes were found at overall avarage frequencies greater than 3%. Average concentration of ascomata along the intervascular rows where they were located was 1 ascoma per 0.5 mm row (∼1000 cm−2 abaxial leaf surface, translating to production of 1.6×107 ascomata m−2 intermediate-height marsh per standing crop of living stems). The fraction of total fungal production allocated to ascomata is speculatively and crudely estimated at about 9%, without taking into account potential loss to invertebrate shredders. At sites with abundances of snails >-50 m−2 peaks of ascospore expulsion (about 50–75 spores cm−2 leaf h−1, 3–5× the overall average rate) observed at snail-free sites were absent. Our measured rate of ascospore expulsion (averaged over snail-free and high-snail sites, and possibly an underestimate) translated to 6.5×104 spores m−2 marsh h−1 for times of freshwater saturation of leaves, and one-third that value for times of saltwater wetting.
Toward protein imprinting with polymer brushes

The authors described an original approach for a surface protein imprinting employing grafting of polymer brushes. Protein molecules were first chemically bound to an ultrathin (1–3 nm) poly(glycidyl methacrylate) reactive polymer layer and later removed by protease treatment. Residual amino acids became grafted to the surface and to a certain extent imitated the surface chemical composition and shape of the template molecule on a nanolevel. The space surrounding the adsorbed biomolecules was modified with grafted poly(ethylene glycol) layer. This led to the formation of islands of spatial nanosized pockets complementary to the protein shape. The adsorbing protein recognized the surfaces imprinted and was anchored to the substrate.
Hydrogen location and diffusion in a two-dimensional metal: Proton magnetic resonance in metallic zirconium monohalide hydrides

Abstract Proton magnetic resonance has been studied in a new class of metal-hydrogen systems, ZrXH, based on the metallic double-layered monohalides of zirconium, ZrCl and ZrBr. The rigid lattice second moments of the proton resonance show that in the hemihydride phases hydrogen predominantly occupies alternate chains of tetrahedral sites within the double layer of close-packed Zr atoms. In the monohydrides all tetrahedral sites are occupied by hydrogen. Activation energies for hydrogen diffusion within the layers are derived from the temperature dependence of the resonance linewidth. A substantial anisotropy of the proton resonance shape is observed at high temperatures.
Effects of Dietary Energy: Protein Ratio and Stocking Density on Growth and Survival of the Common Snapping Turtle Chelydra serpentinal1

Although the common snapping turtle Chelydra serpentina is cultured commercially in the United States, little information is available on nutritional and culture requirements. This study was conducted to evaluate the effects of dietary energy: protein ratio and stocking density on survival, growth, feed consumption, feed conversion, liposomatic index, dress-out percentage, and productive protein value of cultured, common snapping turtles. Hatchling turtles were stocked at 29 and 58 animals/m2 and fed one of seven prepared diets. Six diets contained 30, 35, or 40% protein at two digestible energy (DE) levels (7 or 9 kcal DE/g protein); the seventh was a reference diet (66% protein and 5 kcal DE/g protein) formulated to equal or exceed the whole-body essential amino acid composition of wild, common snapping turtles. Turtles stocked at 58/m2 exhibited greater mortality, lower weight gain, higher feed consumption, less-efficient feed conversion, lower liposomatic index, and lower productive protein value than turtles stocked at 29/m2 (P < 0.05). The reference diet produced the greatest weight gain (P < 0.001). The superior performance of turtles fed the reference diet suggests that: 1) the protein (amino acid) content and/or energy: protein ratio of the reference diet was superior to that of the other diets tested; 2) improvements in growth parameters can be made with dietary manipulation; and 3) high levels of plant protein can be used in prepared, snapping turtle diets.
Parenting style and adolescent clinical severity: Findings from two substance abuse treatment studies

ABSTRACT The purpose of this study was to evaluate the association between authoritative, authoritarian, indulgent, and neglectful parenting, and clinical severity of adolescent substance abuse. Data were examined from 2 substance abuse treatment outcome studies: the Cannabis Youth Treatment (CYT) study and Project Iowa SCY. In both studies, authoritative parenting was associated with less parent-reported substance problem severity compared to neglectful parenting. In CYT, authoritative parenting was also associated with lower conduct disorder severity when compared to authoritarian and neglectful parenting. Findings were not replicated with adolescent-reported outcomes. Lower level of care recommendations are made for authoritatively parented youth when compared to those from authoritarian and neglectful homes. Additional research should rule out shared method variance explanations and investigate whether changes in parenting practices predict substance abuse treatment outcomes.
Infrared Photodiode Optimization For Higher Temperature Operation

The performance of infrared sensitive photodiodes may be improved at higher operating temperatures by a reduction of excess volume in which minority carriers are thermally gen-erated within a diffusion length of the junction. This technique requires surface recombi-nation velocities typically less than 100 cm/sec. Calculations for HgCdTe indicate a peak D* above 1.5 x 1011 cm Hz½/w may be obtained at 190 K for a 5.0 µm cut-off wavelength.© (1978) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A taxonomic monograph of Nearctic Scolytus Geoffroy (Coleoptera, Curculionidae, Scolytinae)

The Nearctic bark beetle genus Scolytus Geoffroy was revised based in part on a molecular and morphological phylogeny. Monophyly of the native species was tested using mitochondrial (COI) and nuclear (28S, CAD, ArgK) genes and 43 morphological characters in parsimony and Bayesian phylogenetic analyses. Parsimony analyses of molecular and combined datasets provided mixed results while Bayesian analysis recovered most nodes with posterior probabilities >90%. Native hardwood- and conifer-feeding Scolytus species were recovered as paraphyletic. Native Nearctic species were recovered as paraphyletic with hardwood-feeding species sister to Palearctic hardwood-feeding species rather than to native conifer-feeding species. The Nearctic conifer-feeding species were monophyletic. Twenty-five species were recognized. Four new synonyms were discovered: Scolytus praeceps LeConte, 1868 (= Scolytus abietis Blackman, 1934; = Scolytus opacus Blackman, 1934), Scolytus reflexus Blackman, 1934 (= Scolytus virgatus Bright, 1972; = Scolytus wickhami Blackman, 1934). Two species were reinstated: Scolytus fiskei Blackman, 1934 and Scolytus silvaticus Bright, 1972. A diagnosis, description, distribution, host records and images were provided for each species and a key is presented to all species.
Alterations in cerebral dopamine function caused by administration ofcis- ortrans-flupenthixol for up to 18 months

Rats received either cis-flupenthixol (0.8-1.2 mg/kg per day) or trans-flupenthixol (0.9-1.2 mg/kg per day) continuously in drinking water for periods up to 18 months. cis-Flupenthixol, but not trans-flupenthixol, initially inhibited apomorphine-induced stereotyped behaviour but by 6 months and thereafter the stereotyped response was enhanced compared to age-matched control animals. Striatal and mesolimbic homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations were elevated for up to 3 months after starting cis-, but not trans-flupenthixol intake, but thereafter levels generally fell below those for age-matched control animals. Dopamine concentrations were not altered by cis- or trans-flupenthixol administration. The number of striatal [3H]spiperone binding sites (Bmax) was decreased by 40% after 1 months' administration of cis-flupenthixol but this gradually reversed, such that by 18 months a 40% increase in Bmax was apparent. Administration of trans-flupenthixol decreased Bmax up to 3 months but thereafter values were not different from those found in age-matched control animals. The dissociation constant (KD) for [3H]spiperone binding in striatum was not altered by 6 months cis-flupenthixol intake, but then increased as drug administration continued. trans-Flupenthixol administration did not alter striatal KD values. Bmax for [3H]spiperone binding to mesolimbic preparations was not altered by up to 12 months cis-flupenthixol intake, but was decreased after 18 months drug administration. cis-Flupenthixol administration had no effect on mesolimbic KD values. Administration of trans-flupenthixol for up to 18 months did not alter mesolimbic Bmax or KD values for [3H]spiperone binding.(ABSTRACT TRUNCATED AT 250 WORDS)
High resolution solar physics from rockets

Abstract Explosive events are highly energetic phenomena that are frequently seen throughout the quiet and active sun, particularly in spectral lines formed at transition zone temperatures. Sufficient observational evidence has now been developed to conclusively demonstrate that some explosive events are caused by magnetic reconnection in emerging magnetic flux regions. It is also consistent with observations of photospheric magnetic flux cancellation to propose that all explosive events are the result of magnetic reconnection. By combining the observational facts concerning photospheric flux cancellation and transition zone explosive events it can be shown that reconnection in the quiet solar atmosphere proceeds in bursts at sites much smaller than the boundary between opposite polarity flux elements that are observed to cancel in magnetograph sequences.
Engrailed cooperates directly with Extradenticle and Homothorax on a distinct class of homeodomain binding sites to repress sloppy paired

Even skipped (Eve) and Engrailed (En) are homeodomain-containing transcriptional repressors with similar DNA binding specificities that are sequentially expressed in Drosophila embryos. The sloppy-paired (slp) locus is a target of repression by both Eve and En. At blastoderm, Eve is expressed in 7 stripes that restrict the posterior border of slp stripes, allowing engrailed (en) gene expression to be initiated in odd-numbered parasegments. En, in turn, prevents expansion of slp stripes after Eve is turned off. Prior studies showed that the two tandem slp transcription units are regulated by cis-regulatory modules (CRMs) with activities that overlap in space and time. An array of CRMs that generate 7 stripes at blastoderm, and later 14 stripes, surround slp1 (Fujioka and Jaynes, 2012). Surprisingly given their similarity in DNA binding specificity and function, responsiveness to ectopic Eve and En indicates that most of their direct target sites are either in distinct CRMs, or in different parts of coregulated CRMs. We localized cooperative binding sites for En, with the homeodomain-containing Hox cofactors Extradenticle (Exd) and Homothorax (Hth), within two CRMs that drive similar expression patterns. Functional analysis revealed two distinct, redundant sites within one CRM. The other CRM contains a single cooperative site that is both necessary and sufficient for repression in the en domain. Correlating in vivo and in vitro analysis suggests that cooperativity with Exd and Hth is a key ingredient in the mechanism of En-dependent repression, and that apparent affinity in vitro is an unreliable predictor of in vivo function.
Determination and genotoxicity of nitrogen heterocycles in a sediment from the black river

The genotoxicity of nitrogen heterocycles isolated from a sediment taken from the Black River near Loraine, Ohio, in an area that received effluents from the coking ovens of a steel plant was studied. These compounds were isolated by gel permeation chromatography and silicic acid adsorption chromatography from the moderately polar fraction of an organic extract of this sediment. Two complex mixtures of secondary and tertiary nitrogen heterocycles containing three to five aromatic rings were characterized using capillary column gas chromatography with selective detection. Both mixtures induced significant unscheduled DNA synthesis in primary rat hepatocytes and accounted for essentially all of the genotoxicity of the fraction from which they were isolated.
Current trials and future directions of the eastern cooperative oncology group breast cancer committee

The Eastern Cooperative Oncology Group (ECOG) continues a major commitment to clinical trials in breast cancer. Trials nearing completion address adjuvant therapy in patients with negative nodes and the interaction of hormonal and cytotoxic adjuvant therapies. ECOG is committed to the performance of intergroup trials that are coordinated among the other major cooperative clinical trials groups in order to accrue the large numbers of patients required for optimal definition of trial results in as few years as possible. Most adjuvant trials to begin the months and years ahead will involve such collaboration
Micropropagation of Astragalus holmgreniorum (Holmgren milkvetch), an endemic and endangered species

Astragalus holmgreniorum (Holmgren milkvetch) is a plant of the Fabaceae family endemic to northwestern Arizona and Washington County, Utah. The species is threatened by urban and recreational development and has been listed as endangered. Here we report a protocol for micropropagation of A. holmgreniorum that could provide a system for preservation of this species and for biotechnological applications. The best response for embryo formation and development of shoots from those embryos was obtained with Treatments 4 (1 mg/L BAP, 0 mg/L 2,4-D) and 6 (1 mg/L BAP, 7 mg/L 2,4-D). The response to these treatments is similar for both stem and leaf explants. The best response was observed when the leaf explants were placed with the abaxial side in contact with the media. After 1–3 weeks exposure of the explants to the media with growth regulators, the explants should be moved to media with no growth regulators to initiate the morphogenetic process. To the best of our knowledge, this is the first report of successful micropropagation of A. holmgreniorum.
THE CREATION OF MEDICARE AND MEDICAID: THE EMERGENCE OF INSURANCE AND MARKETS FOR MENTAL HEALTH SERVICES

Editor's Note: As a follow-up to the precedinarticle first published in the October 1965 issue (see page 461), Richard G. Frank, Ph.D., offers an analysis of the evolving Medicare and Medicaid programs and their impact on public mental health care. He shows that many of the themes raised at the 1965 APA conference on Medicare legislation for psychiatric disorders continue to dominate public debate .
Correlation of left atrial size with p-wave duration in interatrial block.

Background Interatrial block (IAB) [P-wave duration ≥ 110 ms] is associated with left atrial (LA) enlargement (LAE) and pathophysiologic derangements that result in atrial tachyarrhythmias, LA electromechanical dysfunction, and embolism. However, there has been no study addressing the direct correlation of P-wave duration in IAB and LAE. Methods One hundred eighty-one consecutive patients who were admitted to a tertiary care teaching hospital over 5 consecutive days were screened for past transthoracic echocardiogram evaluations and were then matched with ECGs done within 10 days of these echocardiographic investigations. ECGs were evaluated for presence of IAB, and patients were subsequently classified into two groups: control patients and patients with IAB. Patients were also matched for common comorbidities. Mean, SD of age, Pearson correlation coefficient ( r ), p values, and multivariate and linear regression analyses were analyzed for the investigated variables of LA size, left ventricular hypertrophy (LVH), posterior wall thickness, septal thickness, and P-wave duration. Results From the sample (n = 66; mean age ± SD, 71.3 ± 13.7; female gender, 48.5%), the mean LA size in the control group was 36.7 ± 4.01 mm and for the group of patients with IAB (n = 38) was 42.2 ± 7.25 mm (p = 0.004). Linear regression analysis revealed that P-wave duration was significantly correlated with LA size (p = 0.0002, r = 0.606). Conclusions Degree of conduction delay in IAB (P-wave duration) is an independent, direct correlate of LAE, and the regression equation (LA size [in millimeters] = 2.47 ± 0.29 × P-wave duration [in milliseconds]) could be used to estimate LAE.
Integration of Micromouse project with undergraduate curriculum: a large-scale student participation approach

This paper describes a successful integration of the Micromouse project with regular undergraduate courses at California State University, Fullerton. A micromouse is a computer controlled autonomous mobile robot which can find a predetermined destination when placed in an unknown maze. The goals of this paper are to report a complete design example suitable for large-scale student participation and to discuss the benefits of the program from an educator's view point. The Intel 8088 microprocessor was chosen to make the mouse compatible with the PC systems which are universally available. Two stepping motors and eight optical sensors are used to complete the system. Software is written in C and Assembly language with over 2000 lines. Seven micromice have been built since 1990 and several of these mice have won several awards in the IEEE Region Six Southern California competition. Integration of the project with the conventional curriculum has been very successful in motivating students and keeping their interest high. Students show greater enthusiasm for classroom activities and many continue to participate in the project after the semester is over. >
Phase-conjugate pump dithering for high-quality idler generation in a fiber optical parametric amplifier

We experimentally demonstrate a simple technique to cancel the idler broadening in a fiber optical parametric amplifier (OPA) by using two pumps phase-modulated 180/spl deg/ out of phase, one of them being obtained by four-wave mixing in an auxiliary fiber. The resulting OPA idler quality is comparable to that of the output signal.
C-space Subdivision and Integration in Feature-Sensitive Motion Planning

There are many randomized motion planning techniques, but it is often difficult to determine what planning method to apply to best solve a problem. Planners have their own strengths and weaknesses, and each one is best suited to a specific type of problem. In previous work, we proposed a meta-planner that, through analysis of the problem features, subdivides the instance into regions and determines which planner to apply in each region. The results obtained with our prototype system were very promising even though it utilized simplistic strategies for all components. Even so, we did determine that strategies for problem subdivision and for combination of partial regional solutions have a crucial impact on performance. In this paper, we propose new methods for these steps to improve the performance of the meta-planner. For problem subdivision, we propose two new methods: a method based on ‘ gaps’ and a method based on information theory. For combining partial solutions, we propose two new methods that concentrate on neighboring areas of the regional solutions. We present results that show the performance gain achieved by utilizing these new strategies.
Design and Characterization of High-Voltage Silicon Carbide Emitter Turn-off Thyristor

A novel MOS-controlled silicon carbide (SiC) thyristor device, the SiC emitter turn-off thyristor (ETO), as a promising technology for future high-voltage and high-frequency switching applications has been developed. The world's first 4.5-kV SiC p-type ETO prototype based on a 0.36 cm2 SiC p-type gate turn-off (GTO) shows a forward voltage drop of 4.6 V at a current density of 25 A/cm2 and a turn-off energy loss of 9.88 mJ. The low loss shows that the SiC ETO could operate at a 4-kHz frequency with a conventional thermal management system. This frequency capability is about four times higher than the 4.5-kV-class silicon power devices. The numerical simulations and theoretical analysis have been carried out to show the potentially improved performance of the high-voltage SiC ETOs. The results show that the high-voltage (10-kV) SiC n-type ETO has much better tradeoff performance than that of the p-type ETO due to a smaller current gain of the lower bipolar transistor in the SiC n-type GTO. Further improvement of the 10-kV SiC n-type ETO can be made with the optimum design of the drift layer carrier lifetime and buffer layer doping concentration of the 10-kV SiC GTO. The theoretical analysis and numerical simulation shows the SiC ETO also has the excellent reverse bias safe operating area. The experimental and theoretical studies show that the SiC ETO is a promising candidate for high-voltage (> 5 kV) power conversion applications.
Facilitating distributed time-triggered simulation of embedded systems and environments

The distributed time-triggered simulation (DTS) scheme is a new type of approach to real-time simulation based on parallel/distributed computing. It requires a global time base which provides consistent real-time information to application software running on distributed nodes. The exploitation of its full potential requires advanced computing platforms such as highly parallel computing platforms. Recent developments in the scientific foundation for DTS and the execution engines and programming tools supporting DTS are briefly reviewed.
Imaging the Evolution of Reactivation Pulmonary Tuberculosis in Mice Using 18F-FDG PET

Latent tuberculosis infection affects one third of the world’s population and can reactivate (relapse) decades later. However, current technologies, dependent on postmortem analyses, cannot follow the temporal evolution of disease. Methods: C3HeB/FeJ mice, which develop necrotic and hypoxic tuberculosis lesions, were aerosol-infected with Mycobacterium tuberculosis. PET and CT were used to serially image the same cohort of infected mice through pretreatment, tuberculosis treatment, and subsequent development of relapse. Results: A novel diffeomorphic registration was successfully used to monitor the spatial evolution of individual pulmonary lesions. Although most lesions during relapse developed in the same regions as those noted during pretreatment, several lesions also arose de novo within regions with no prior lesions. Conclusion: This study presents a novel model that simulates infection and reactivation disease as seen in humans and could prove valuable to study tuberculosis pathogenesis and evaluate novel therapeutics.
Would Achievement Testing of Students Solve the Problem of Incompetent Language Teachers

a significant time saving for the student of Russian at the computer. The central concept of PLATO is individualization of learning. Each student proceeds through the material in privacy at his own pace. He works through the program in his own way; fast or slow, with little or repeated branching, repeating sections if necessary, until not only the teacher's requirements are met, but the student himself is satisfied. His answers are judged immediately, followed by instant feed-back in the form of messages on the screen. The author provides sufficient meaningful drill with testing check points in order to insure mastery of the lessons. In case of serious misunderstanding on the part of the student, remedial branching is either suggested or required by the author. Since the changing display focuses his complete attention, each student is totally absorbed in his own work. The PLATO class period is a completely active one for the student. We have found that the student masters the translation of Russian prose at the computer efficiently and economically.7 7The authors wish to thank Professors Clayton L. Dawson, Steven P. Hill, and Rasio Dunatov of the Slavic Department of the University of Illinois for their contributions and cooperation in the development of the course. We are. indebted to Henry and Maria Zalucky, also of the Slavic Department, who advised us on modern Russian usage in the preparation of all material. Our efforts were at all times facilitated by Professor D. L. Bitzer, Director of the Computer-Based Education Research Laboratory and his staff. We especially appreciate the innovative programming techniques furnished by Mr. P. Tenczar and Mr. R. Blomme. We wish to thank Professor S. G. Smith of the Chemistry Department of the University of Illinois for the preparation of the figures used in this paper. Evaluative analysis of data was provided by Mr. R. A. Avner of the laboratory. The Computer-Based Education Research Laboratory is supported by the National Science Foundation under grants NSF GJ-974 and NSF GJ-81 and The State of Illinois. The laboratory was formerly supported also by ONR nonr 3985 (08), Advanced Research Projects Agency; U.S. Department of Health, Education and Welfare; and U.S. Navy, University of Southern California Sub-contract.
Vertical profiling of precipitation using passive microwave observations: The main impediment and a proposed solution

[1] Several methods have been proposed to train microwave radiometers to retrieve precipitation rates estimated by a radar that observed the same location at the same time. These radar-trained passive microwave algorithms differ in the quantities that are estimated; some estimate the vertically integrated liquid water, whereas others estimate the near-surface precipitation. Since it is no more or less credible to estimate the rain rate at the surface than it is to estimate the rain rate at any discrete altitude, it is particularly interesting to quantify to what extent it is indeed feasible to estimate vertical profiles of precipitation from a passive microwave radiometer, what the obstacles are, and what vertical resolution would be achievable. To that end, we selected five study regions and started by quantifying the vertical variability of rainfall as derived from the Tropical Rainfall Measuring Mission (TRMM) radar. Two cases emerged: a monsoon-like case where the first principal component of the vertical precipitation accounts for about 90% of the variability and a Mediterranean-like case where the first principal component accounts for about 80% of the variability. A Bayesian approach was applied to the TRMM Microwave Imager measurements colocated with the radar profiles. For the monsoon-like regions, it produced estimates of rain rates at 250-meter vertical increments, which compared well with the TRMM radar estimates. For the Mediterranean-like regions, the retrieval errors were very large. We therefore proceeded to identify the main reason for the failure of the straightforward training method. It turns out to be the unknown signature of the sea surface in the portion of the beam that does not contain precipitation. In the problematic Mediterranean case, our original straightforward approach can still be applied to measurements that do not suffer from this identifiable partial beam filling. For measurements that do, we derive a filtering approach to neutralize the variability of the partial surface signature and thus overcome the problem.
Assessing Grain-Size Correspondence Between Flow and Deposits of Controlled Floods In the Colorado River, U.S.A.

Abstract Flood-deposited sediment has been used to decipher environmental parameters such as variability in watershed sediment supply, paleoflood hydrology, and channel morphology. It is not well known, however, how accurately the deposits reflect sedimentary processes within the flow, and hence what sampling intensity is needed to decipher records of recent or long-past conditions. We examine these problems using deposits from dam-regulated floods in the Colorado River corridor through Marble Canyon–Grand Canyon, Arizona, U.S.A., in which steady-peaked floods represent a simple end-member case. For these simple floods, most deposits show inverse grading that reflects coarsening suspended sediment (a result of fine-sediment-supply limitation), but there is enough eddy-scale variability that some profiles show normal grading that did not reflect grain-size evolution in the flow as a whole. To infer systemwide grain-size evolution in modern or ancient depositional systems requires sampling enough deposit profiles that the standard error of the mean of grain-size-change measurements becomes small relative to the magnitude of observed changes. For simple, steady-peaked floods, 5–10 profiles or fewer may suffice to characterize grain-size trends robustly, but many more samples may be needed from deposits with greater variability in their grain-size evolution.
Determinants of Prostate Cancer–Specific Survival After Radiation Therapy for Patients With Clinically Localized Prostate Cancer

PURPOSE: Identifying pretreatment and posttreatment predictors of time to prostate cancer–specific death (PCSD) after external-beam radiation therapy (RT) was the subject of this study. PATIENTS AND METHODS: A Cox regression analysis was used to evaluate the ability of the pretreatment risk group to predict time to PCSD for 381 patients who underwent RT for clinically localized prostate cancer. Posttreatment factors analyzed for the 94 patients who experienced prostate-specific antigen (PSA) failure included the time to PSA failure, the posttreatment PSA doubling time (DT), and the timing of salvage hormonal therapy. RESULTS: Despite the median age of 73 years at diagnosis, 45% of patients with high-risk disease were estimated to die from prostate cancer within 10 years after RT compared with 0% (P = .004) and 6% (P = .05) for patients with low- or intermediate-risk disease, respectively. Predictors of time to PCSD after PSA failure included PSA DT (P = .01) and delayed use of hormonal therapy (P ≤ .002)....
Roles of trk family neurotrophin receptors in medullary thyroid carcinoma development and progression

Although initiating mutations in the ret protooncogene have been found in familial and sporadic medullary thyroid carcinoma (MTC), the molecular events underlying subsequent tumor progression stages are unknown. We now report that changes in trk family neurotrophin receptor expression appear to be involved in both preneoplastic thyroid C cell hyperplasia and later tumor progression. Only a subset of normal C cells expresses trk family receptors, but, in C cell hyperplasia, the affected cells consistently express trkB, with variable expression of trkA and trkC. In later stages of gross MTC tumors, trkB expression was substantially reduced, while trkC expression was increased and often intense. In a cell culture model of MTC, exogenous trkB expression resulted in severely impaired tumorigenicity and was associated with 11-fold lower levels of the angiogenesis factor vascular endothelial growth factor. These results suggest that trk family receptor genes participate in MTC development and progression, and, in particular, that trkB may limit MTC tumor growth by inhibition of angiogenesis.
Bitmap indexes for relational XML twig query processing

Due to an increasing volume of XML data, it is considered prudent to store XML data on an industry-strength database system instead of relying on a domain specific application or a file system. For shredded XML data stored in the relational tables, however, it may not be straightforward to apply existing algorithms for twig query processing, because most of the algorithms require XML data to be accessed in a form of streams of elements grouped by their tags and sorted in a particular order. In order to support XML query processing within the common framework of relational database systems, we first propose several bitmap indexes for supporting holistic twig joins on XML data stored in the relational tables. Since bitmap indexes are well supported in most of the commercial and open-source database systems, the proposed bitmap indexes and twig query processing algorithms can be incorporated into the relational query processing framework with more ease. The proposed query processing algorithms are efficient in terms of both time and space, since the compressed bitmap indexes stay compressed during query processing. In addition, we propose a hybrid index which computes twig query solutions with only bit-vectors, without accessing labeled XML elements stored in the relational tables.