cssi/SciSciGPT-SciSciNet huggingface dataset:
Dispersion-managed mode locking

The pulse shape and spectrum of ultrashort-pulse Ti:sapphire mode-locked lasers are explained by a model akin to dispersion-managed pulse propagation of optical communications. The pulse is characterized as a nonlinear Bloch wave in a periodic structure. The ultimate spectral width is limited by dispersion and mirror bandwidth and less strongly by gain filtering. The main role of Kerr-lens mode locking is to provide stability against noise buildup. One-dimensional computer simulations are sufficient to explain the major pulse-shaping dynamics. Results are compared with experiment.
The Impact of Desegregation on Cognition among Older African Americans.

One of the single most influential factors on current and future cognitive functioning is educational attainment. We examined the influence of educational desegregation on cognitive performance usi...
Semiconductor quantum dot mixture as a lossless negative dielectric constant optical material

Prospects for a lossless negative dielectric constant material for optical devices are studied. Simulations show that, with sufficient gain, a mixture of two semiconductor quantum dots can produce an isotropic effective dielectric constant that is lossless and negative. Both analytical homogenizations based on the work of Maxwell Garnett and frequency-dependent dielectric constants from inversion of numerical computations of scattered fields are used to establish the dielectric constants of a mixture of gain and loss dots. Over length scales where homogenization is meaningful, this material could be used to achieve lossless ``metal-insulator'' optical waveguides and hence a small optical mode volume.
Optical features associated with thermohaline structures

A subset of the Optical Dynamics Experiment (ODEX) data set taken from the R/P FLIP in the eastern North Pacific on November 8, 1982 is used to examine the relatiohips among physical and bio-optical parameters. Rapid profiling was done with a CTD equipped with a beam transmissometer and an in situ fluorometer. Intense thermohaline structures are observed to vary on time scales as short as 15 min. Interestingly, the temporal and vertical spatial variability in the physical parameters are often well-correlated with the corresponding variability in the optical parameters. In addition, the extent and intensity of the fluorescence maximum region appears to be modulated by a low frequency internal wave.
Protoporphyrin IX Fluorescence Imaging of Glioma Tumor Growth in the Murine Brain

Aminolevulinic acid induced Protoporphyrin IX fluorescence accumulates preferentially in brain tumor tissue. Microscopic and macroscopic studies are contrasted to determine the utility as a diagnostic measure of tumor extent in vivo for tracking therapeutic response.
Cerebral Venous Thrombosis Complicated by Hemorrhagic Infarction: Factors Affecting the Initiation and Safety of Anticoagulation

Background and Purpose: Anticoagulation (AC) may improve outcome in cerebral venous thrombosis (CVT), even when complicated by pretreatment hemorrhagic infarction (HI). The HI chara
Measurement of the Dynamic Association/Dissociation of Membrane Biomolecules to Different Lipid Membrane Phases

Separation of distinct lipid membrane domains in cell membranes has been suggested to play important roles in many cellular processes by providing microenvironments to cluster or to isolate membrane biomolecules. One important class of membrane domain is called a lipid raft and some signaling proteins and glycolipids have high affinity for these domains. However, many experimental determinations of biomolecule residency in rafts occur at equilibrium or fixed conditions, precluding measurement of dynamic information. We report a new method for measuring the partitioning kinetics of membrane biomolecules to different lipid phases using a patterned supported lipid bilayer platform composed of liquid-ordered (lipid raft) and liquid-disordered (unsaturated lipid-rich) coexistent phases. Laminar flow inside a microfluidic channel patterns bilayers with coexistent phases in predetermined locations, eliminating the need for additional components to label the phases. Using a hydrodynamic force provided by the bulk flow in the microchannel, membrane-bound species can be transported in the bilayers. The pre-defined location of stably coexistent phases, in addition to the controllable movement of the target species, allow us to establish when and where the target molecules approach or leave different lipid phases. Using this approach with appropriate experimental designs, we obtain the association and dissociation kinetic parameters for three membrane-bound species, including the glycolipid, GM1, an important cell signaling molecule. We examine two different analogs of GM1 and conclude that structural differences between them impact the kinetics of association of these molecules to raft-like phases. One possible extension is measuring the partitioning kinetics of other glycolipids or lipid-linked proteins with posttranslational modifications to provide insight into how structural factors, membrane compositions, and environmental factors influence dynamic partitioning. We also discuss the possibilities and limitations for this method.
A model for multidisciplinary graduate education in modelling and simulation

Modelling and Simulation (M&S) is increasingly important in numerous disciplines. M&S also has gained acceptance as a discipline in its own right. There is growing demand for at least two different approaches to M&S graduate education, one path for users and another for developers of M&S. Thus, the traditional department-focused approach is no longer adequate for M&S education. This paper outlines the development of a multidisciplinary approach to M&S graduate education at Old Dominion University. The approach encourages development of a number of M&S programmes, coordinated by university-level oversight, in which all academic colleges participate.
Fascism and attitudes toward mandatory sterilization: the development of an attitude scale.

Summary In the first part of a two-part study, 150 undergraduate and graduate college students of both sexes participated in the development of a Likert type attitude scale measuring attitudes toward mandatory sterilization. In the second part of the investigation, 58 male and 48 female undergraduate college students with a mean age of 24.2 years, participated in a study assessing the reliability of the scale, and the relationship between attitudes toward sterilization and fascism. The final scale consists of 36 items selected by the criterion of internal consistency. The scale has high internal reliability and relates moderately to fascist attitudes. It is suggested that positive attitudes toward mandatory sterilization and fascism have common ideological roots in the predominant emphasis on the nature rather than the nurture of human behavior.
Limited expression of a diverged β-tubulin gene during soybean (Glycine max [L.] Merr.) development

We examined the developmental expression of a diverged soybean β-tubulin gene (designated sb-1), which had been cloned and sequenced previously. A probe specific for the sb-1 gene was constructed from the 3′ transcribed untranslated sequence. As a control, a more general probe for β-tubulin genes and their transcripts was constructed from a highly conserved region of the third exon of another soybean β-tubulin gene, sb-2. Poly(A)+ RNA, extracted from various soybean tissues and organs, was probed alternatively with the sb-1 gene-specific probe and with the generic β-tubulin probe. Levels of β-tubulin transcripts recognized by the generic probe differed by a factor of approximately 3 in the different tissues and organs and varied with the state of organ development. Highest levels were found in young, unexpanded leaves and they decreased as leaf maturation occurred. In contrast, transcripts of sb-1 were nearly undetectable in young leaves, and they increased as leaf maturation occurred. Levels of sb-1 transcript were low in all organs of the light-grown plant examined, except the hypocotyl, where they were approximately 10-fold higher. However, the highest levels of sb-1 transcripts were observed in elongating hypocotyls of etiolated seedlings. Exposure of six-day-old etiolated seedlings to light for 12 hours halted further hypocotyl elongation and brought about a dramatic, nearly 100-fold, decrease in the steady-state level of sb-1 transcripts.
A beam intensity monitor for the Loma Linda cancer therapy proton accelerator.

A beam intensity monitor was tested in a 230-MeV proton beam at the Loma Linda Proton Therapy Accelerator during its commissioning at Fermi National Accelerator Laboratory. The intensity monitor was designed to regulate the beam intensity extracted from the proton synchrotron. The proton beam is tunable between 70 and 250 MeV with an adjustable intensity between 10{sup 10} and 10{sup 11} protons per spill. A beam spill is typically 1 s long with a 2-s repetition period. The intensity monitor must be radiation hard, expose minimum mass to the beam, and measure intensity to 1% in 1-ms time intervals. To this end, a 5-cm-thick xenon gas scintillator optically coupled to a photomultiplier tube (PMT) was tested to measure its response to the proton beam. The gas cell was operated at 1.2 atm of pressure and has 12.7-{mu}m-thick titanium entrance and exit foils. The total mass exposed to the beam is 0.14 g/cm{sup 2} and is dominated by the titanium windows. This mass corresponds to a range attenuation equal to 1.4 mm of water. The energy lost to the xenon gas is about 70 keV per proton. Each passing proton will produce approximately 2000 photons. With a detection efficiency on themore » order of 0.05% for this UV light, one would anticipate over 10{sup 10} photoelectrons per second. In a 1-ms time bin there will be approximately 10{sup 7} photoelectrons. This yields a resolution limited by systematics. For unregulated 0.4-s proton spills, we observe a response bandwidth in excess of 10{sup 4} Hz. While signal-to-noise and linearity were not easily measured, we estimate as few as 10{sup 3} protons can be observed suggesting a dynamic range in excess of 10{sup 5} is available.« less
Ablative photodecomposition of polymer films by pulsed far‐ultraviolet (193 nm) laser radiation: Dependence of etch depth on experimental conditions

Photodecomposition ablative de polyimide, polyterephtalate d'ethylene et polycarbonate et du PMMA par des impulsions laser a 193 nm
Neuroma of the common bile duct

Two cases of neuroma of the common bile duct (CBD) associated with jaundice and cholangitis both 15 years after cholecystectomy are presented. The surgical treatment, excision of the diseased CBD, followed by Roux-en-Y biliary drainage in one case and excision of the tumor with T-tube drainage in the other, was curative. A review of the world literature revealed 20 prior cases of CBD neuromas, 19 associated with jaundice. None was diagnosed prior to operation or autopsy. Mortality of treatment was 15% and all deaths were associated with a failure to excise the neuroma.
ATPase activities in peroxisome-proliferating yeast.

Preliminary studies on yeast peroxisomes have suggested that the membrane of these organelles may contain a proton-pumping ATPase. It has been reported that peroxisome-associated activity is similar to the F0-F1 mitochondrial type ATPase in its sensitivity to azide at pH 9.0, but characteristics of the plasma membrane type ATPase are also evident in peroxisomal preparations in that they exhibit pH 6.5 activity that is sensitive to vanadate. A comparative study of the prominent organellar ATPase activities was undertaken as a probe into the existence of an enzyme that is unique to the peroxisome, and biochemical properties of yeast mitochondrial, plasma membrane, together with peroxisomally-associated H +-ATPase are presented. Enzyme marker analysis of sucrose gradient fractions revealed a high degree of correlation between the amount of azide-sensitive pH 9.0 ATPase activity and that of the mitochondrial membrane marker, cytochrome c oxidase, in peroxisomal preparations. Purified mitochondrial and peroxisomally-associated activities were highly sensitive to the presence of sodium azide, N,N′-dicyclohexylcarbodiimide (DCCD) and venturicidin when measured at pH 9.0. Comparisons of peroxisomal activities with those of the purified plasma membrane at pH 6.0 in the presence of azide showed similar sensitivity profiles with respect to inhibitors of yeast plasma membrane ATPases such as vanadate and p-chloromercuriphenyl-sulfonic acid (CMP). Purified peroxisomal membranes, furthermore, reacted with antibody to the mitochondrial F1 subunit (as revealed by Western blot analysis), and [35S]methionine-labeled, glucose-grown cells processed with unlabeled methanol-grown cells, yielded sucrose gradient fractions that were radioactive in bands that were also recognized by F1 antibody. Isolated fractions in these experiments had similar ratios of cpm:pH 9.0 ATPase activities, suggesting that this activity is mitochondrial in origin. The data presented for the characteristics of the peroxisomally-associated activity strongly suggest that the majority of the ATPase activity found in peroxisomal preparations is derived from other organelles.
Protein Kinase C Activation Mimics but Does Not Mediate Thyrotropin-Induced Desensitization of Adenylyl Cyclase in Cultured Dog Thyroid Cells*

The mechanism and site(s) of the defect responsible for desensitization to hormone stimulation of adenylyl cyclase (AC) vary with cell type. Plasma membrane preparations were assayed after treatment of primary cultured dog thyroid cells to determine the role of the TSH receptor, stimulatory and inhibitory guanine nucleotide binding proteins (G8 and Gi), and catalytic unit in AC desensitization. Exposure of cells to TSH or the phorbol ester, 12-0-tetradecanoyl-phorbol-13-acetate (TPA), caused time dependent decreases in TSH-stimulated AC and [125I]TSH binding with approximately 50% decreases seen after 18 h; Bt2cAMP was unable to reproduce the TSH effect. Whereas TSH treatment caused concomitant decreases (-25%) in both cyclase activity and [125I]TSH binding after 2 h, TPA treatment decreased AC activity after 6 h and binding only after 18 h. The protein kinase C inhibitor, H-7, prevented TPAinduced but not TSH-induced effects on AC and hormone binding. Membrane AC activation by cholera toxin or forskolin ...
Changes in the geographical distributions of global emissions of NOx and SOx from fossil-fuel combustion between 1966 and 1980

Abstract The amount of a fossil-fuel related pollutant released in a region must be functionally dependent on the amount of fuel consumed. Appealing to this general principle we obtained regression relationships between fuel consumption and NO x and SO x generated in the combustion of these fuels-for countries where emission data are available. The statistical relationships were then used to estimate NO x and SO x emissions in other countries. In this manner statistically consistent geographical maps of emissions can be produced for each year for which fuel consumption estimates are available. We illustrate the usefulness of the method by presenting global emissions for 1966 and 1980 on a latitude-longitude grid appropriate for general circulation models of the atmosphere. The results show that, although the greatest rates of emission occur in the northern mid-latitudes, the greatest increases from 1966 to 1980 have taken place in the tropics.
Kinetic Study of the Copolymerization of Methyl Methacrylate and Methyl Acrylate Using Quantum Chemistry

Copolymerization of methyl methacrylate and methyl acrylate was studied using quantum chemistry and transition state theory to estimate the kinetic parameters for propagation (kp, A, Ea). A terminal model and penultimate effect models were studied explicitly by examining 28 different addition reactions involving monomeric, dimeric, and trimeric radicals and monomers for both self- and cross-propagation. Reactant and product conformations were optimized using a combination of a conventional optimization algorithm and relaxed potential energy scans for individual single-bond rotors using unrestricted B3LYP/6-31G(d). The electronic energy was then calculated using MPWB1K/6-31G(d,p). Low frequencies were treated using a one-dimensional internal rotor model. A and Ea were regressed based on a plot of ln kp vs 1/T over a temperature range of 296.15−800 K. Reactivity ratios (r) characterizing the terminal model were calculated based on the monomeric, dimeric, and trimeric radical addition reactions, and ratios f...
Applications Of A Bicubic B-Spline Data Reduction Algorithm

A square root information filter (SRIF) data reduction method with a bicubic B-spline estimator is used to reduce optical data taken at points on a rectangular strip. It is shown that some difficulties encountered when using Zernike or Fourier estimators are avoided by using B-splines. Standard statistical measures of the data trend as they relate to instrument noise are easily found as a by-product of the SRIF bicubic B-spline data reduction process.
Treatment of the child with chemical diabetes mellitus.

Abstract Tolbutamide has been administered chronically to eight children with asymptomatic, chemical diabetes mellitus. Observations have continued over 3 yr. In each, glucose tolerance converted to normal in association with tolbutamide therapy, and insulin response to glucose improved but did not become normal. Hyperinsulinism remained characteristic of these subjects. None have progressed to overt diabetes during the period of observation, but it was necessary to stop tolbutamide in two children because of hypoglycemia.
Management of Active and Programmable Networks

Information comes in two general flavors: non-executable (a string of bits with predefined meaning and already in their final form) and executable (bits of program code, intended to be executed, and whose result after execution is of primary interest). Our understanding of non-executable information is relatively deep and well known. Characteristics and behavior of executable information, on the contrary, is far from known: no one can say in general when the smallest program that performs a task has been generated—no one can predict the impact of changes to the bits of program code—no one can determine in general when or if a program will end; most practitioners steer clear of applying it within the network and even fewer researchers explore algorithmic information theory with respect to managing a network. Active networks [1‐3] provide a framework enabling the previously discussed flavors of information to co-exist within, and modify the behavior of, communication networks. Executable code and non-executable data reside within network packets such that injected code can modify behavior of lowlevel network layers. Programmable networks allow customization of dataplane and control-plane services (e.g., using network processor methods in high-speed routers or software radio methods in wireless networks). These networks raise new management issues regarding the relation and tradeoffs among communication and computation, configuration, fault, security, performance, and accounting management. Ad hoc wireless networks and software radios are being facilitated by the advancement of active networks; however, they add another level of complexity to active and programmable network management.
Respiratory distress during panic attacks associated with agoraphobia.

59 patients with agoraphobia and panic attacks completed check lists of physical and cognitive panic-related symptoms to estimate the extent to which respiratory distress is associated with panic. Over half of the patients reported experiencing difficulty breathing during most or all panic attacks, but respiratory difficulty was not consistently associated with panic. Further research is needed using alternative methods of assessment, but these findings suggest that biologically oriented explanations of panic which ascribe a precipitative role to respiratory dysfunction cannot account for many of the panic attacks experienced by agoraphobics.
High-frequency acoustic inversion using a military mine-hunting sonar

Summary form only given. Because the AQS-20's Volume Search Sonar (VSS) contains multiple beams at a number of grazing angles, the NRL Sediment Mapping System can be used to invert the backscattered acoustic signal for seafloor sediment parameters. Backscattering strength is computed for each beam and averaged over several pings. A physical backscatter model that predicts backscattering strength as a function of grazing angle is used with a simulated annealing inversion to find the model parameters. This paper discusses the inversion results using VSS data from a test off the coast of Panama City, Florida. The analysis results include sediment-water density ratio, bottom relief spectral strength (roughness parameter), and a volume interaction parameter. From these model parameters, we estimate mean grain size and root-mean square interface roughness. The sediment-water density ratios from the inversion are compared with the solutions from another NRL bottom classification system using a normal incidence impedance-based inversion technique.
Kinetic evaluation of tin‐POMS catalyst for urethane reactions

We report the activity for a new tin-polyhedral oligomeric metal silsesquioxane (POMS) catalyst in 1-butanol and 2-butanol model reactions with 4,4'-methylenebis(cyclohexylisocyanate) (H 12 MDI) in toluene and N,N-dimethylformamide (DMF). Kinetic rate constants for varying levels of tin-POMS ranging between 100 ppm and 1000 ppm tin are reported. We observed urethane reactions in toluene to follow second order reaction kinetics, whereas similar reactions in DMF followed first order reaction kinetics. We determined tin-POMS is an efficient catalyst system for urethane reactions and found the new catalyst to be easy to handle, soluble, and very effective for catalyzing urethane reactions. By direct comparison of a model reaction between tin-POMS and dibutyltin dilaurate (DBTDL), tin-POMS was found to be quite similar to DBTDL for urethane catalytic activity. In addition, we show the efficacy for tin-POMS to be an excellent polyurethane reaction catalyst through a model reaction of H 12 MDI with 2000 g/mol poly(e-caprolactone) diol.
Use of a cylindrical Langmuir probe for the characterization of charged particle populations in a planar, diode glow discharge device

Abstract The application of the single Langmuir probe techniques to the measurement of electron temperature, electron number density, positive ion number density, average electron energy and electron energy distribution functions in the negative glow region of a planar diode argon glow discharge device is described. These charged particle properties were determined as a function of axial distance from a copper cathode surface at various discharge conditions. The effect of source pressure was determined in both constant current and constant voltage modes. The general range of the charged particle properties are electron temperature 0.20–0.35 eV; electron/ion densities on the order of 1011 cm−3; and average electron energy 0.7–1.0 eV. The electron energy distribution functions show non-Maxwellian distributions, with depletion of high energy electrons.
Validation of Criterion-Referenced Standards for the Mile Run and Progressive Aerobic Cardiovascular Endurance Tests

The purpose of this study was to validate criterion-referenced standards for cardiovascular endurance tests using the criterion-groups validation model. Adolescent boys and girls assigned to either untrained or trained groups were administered the mile run and Progressive Aerobic Cardiovascular Endurance Run (PACER) tests. Selection of optimal criterion standards was based on finding a cutting score that minimized the probability of misclassification errors and maximized the probability of making correct decisions based on participation in physical activity. The results of this study suggest that recent changes in FITNESSGRAM standards are appropriate, especially for the PACER test. While modifications of standards have corrected somewhat for disparities in passing rates between the mile run and the PACER, especially for girls, further study of standards is necessary.
Optimization of short channel CMOS LNAs by geometric programming

Geometric programming is a method used to produce globally optimal circuit parameters with high computational efficiency. This method is applied to a short channel (90 nm and 180 nm) CMOS Low Noise Amplifier (LNA) design with common source inductive degeneration to obtain optimal design parameters for minimizing the noise figure. Geometric programming (GP) compatible functions have been determined to calculate the noise figure of short channel CMOS devices by taking into consideration channel length modulation and velocity saturation effects. Optimal design parameters (i.e., channel width and noise figure) from GP optimization are validated by comparing them with simulations obtained from Agilent's Advanced Design Systems (ADS) software. Furthermore, tradeoff analyses have been performed to examine the influence of various design parameters such as quality factor and drain current on the design optimization. With the continuous downscaling of CMOS technologies, GP optimization offers high performance advantages in the optimal design of short channel CMOS LNAs.
Impedance spectroscopy of single and polycrystalline olivine: Evidence for grain boundary transport

The impedance spectra of single and polycrystalline olivine display two and three impedance arcs, respectively. Impedance spectra of single crystal olivine, polycrystalline olivine compacts, and natural dunite are compared to deduce the causes of the different impedance arcs. Variation of sample dimensions and use of three- and four-electrode configurations aid in the interpretation. The resistance of the two highest frequency mechanisms varies directly with the length to area ratio (l/A) of the sample. Experiments using the four-electrode configuration confirm that the lowest frequency impedance arc is caused by processes at the sample-electrode interface. In both single and polycrystalline samples the highest frequency mechanism is interpreted as bulk (grain interior) conduction, and the lowest frequency mechanism is attributed to sample-electrode interface effects. In the polycrystalline samples, the intermediate frequency mechanism is interpreted as the grain boundary conduction mechanism. The resistances of the grain interior and grain boundary mechanisms add in a series manner.
Measurements of radon emanation from Apollo 11, 12, and 14 fines

Less than 0.13% of all222Rn atoms produced in Apollo 11 fines 10084 emante from this material at temperatures ranging from about 25–35°C and a pressure of about 10−2 torr. The value for Apollo 12 fines 12007 is < 0.73% or < 0.57%, depending on the adopted U content. For the combined Apollo 14 fines 14003 + 14259 we find a minimum value of 0.23%, and a maximum value of 0.55%. Emanation of220Rn has been observed in the case of the Apollo 14 fines. The relatively small emanation rates could be due to the absence of interstitial air and water on the lunar surface as has been suggested by Lindstrom et al. [5]. However, it seems also possible that U and Th are principally contained in the lunar fines within minerals which are intrinsically poor radon emanators, such as zircons. The small emanation rates require 100%222Rn escape from a regolith thickness of about 10 m (U ∼ 4 ppm) to explain the observed210Po activity in Mare Tranquillitatis by Turkevich et al. [3]. However, this problem cannot be settled satisfactorily until emanation measurements have been made at temperatures of about 120°C.
Curve Fit: a pixel-level raster regression tool for mapping spatial patterns

Summary 1. Despite the fact that pixels (i.e. picture elements) are the basic sampling units of maps, we are aware of no software package or tool that allows users to model changes that may occur at such fine spatial resolutions over broad geographic extents. 2. Curve Fit is an extension to the application ArcMap that allows users to conduct linear or nonlinear regression analysis on the range of values found within input ras ter data sets (geo-referenced images), independently for each pixel. 3. Outputs consist of raster surfaces of regression model parameter estimates, standard errors, goodness-of-fit estimates and multimodel inference measures. 4. Curve fit outputs characterize continuous spatial or temporal change across a series of raster data sets.
Regular rings and distributive lattices

We show that a finite lattice is isomorphic to the lattice of ideals in a regular ring if and only if it is distributive. We also study the countable case.
Preclassic Maya Pottery at Cuello, Belize

Preclassic Maya Pottery at Cuello, Belize. Laura J. Kosakowsky. Anthropological Papers of the University of Arizonza, Number 47. Tuscon: The University of Arizona Press, 1987. vil. 101 pp. $29.95 (paper). ISBN 0-8165-1017-2
Pre-emptive dynorphin and N-methyl-d-aspartate glutamate receptor antagonism alters spinal immunocytochemistry but not allodynia following complete peripheral nerve injury

Abstract The development of chronically painful states following peripheral nerve injury may involve different mechanisms depending on the nature and extent of the nerve lesion. The altered spinal neurochemistry of two substances, the excitatory amino acid glutamate operating via the N -methyl- d -aspartate receptor and the endogenous opioid peptide dynorphin, have been implicated in behavioral sequelae that follow partial peripheral nerve injury. In addition, dynorphin has nonopioid functions which may involve the N -methyl- d -aspartate receptor. We investigated two hypotheses: that the development of mechanical allodynia following complete nerve injury is not greatly influenced by the N -methyl- d -aspartate receptor, and that spinal dynorphin and glutamate expression is interdependent. These studies employed sciatic cryoneurolysis, a complete but transient peripheral nerve injury that results in a delayed mechanical allodynia beginning 21–28 days after injury. Rats were administered dizocipline maleate (MK-801) at 0.25 mg/kg twice per day intraperitoneally from days 0–7 or from days 0–21 post-lesion to pre-emptively block the N -methyl- d -aspartate receptor. In a separate group of rats, an antibody to dynorphin was administered intraperitoneally at 16.6 mg/kg twice per day from days 14 to 21 post-lesion. For all groups, the outcome of allodynia behavior was assessed using von Frey filaments at 42 days post-lesion and the resulting dynorphin and glutamate immunoreactivity in the substantia gelatinosa was measured using proportional area stained and relative optical density, respectively. Only the 0–7 day MK-801 treatment increased the resulting mechanical thresholds significantly (mean ± S.E.M. 7.0 ± 1.2 g) when compared to saline-injected animals (3.9 ± 0.6 g). However, this effect did not prevent allodynia since baseline thresholds were 12 or 15 g for each group. With regard to resulting spinal immunoreactivity, anti-dynorphin antibody treatment significantly increased glutamate immunoreactivity when compared to saline-treated animals (mean relative optical density ± S.E.M. = 807.2 ± 3.6 versus 779.6 ± 8.3, respectively; P =0.01) at 42 days post-lesion. We conclude that the development of allodynia following sciatic cryoneurolysis peripheral nerve injury involved a minimal contribution from N -methyl- d -aspartate receptor activity. In addition, this study demonstrated that decreasing available dynorphin using antiserum had a significant and lasting effect on spinal glutamate expression without altering the outcome of allodynia. These conclusions suggest that etiological mechanisms leading to pain behaviors are not equal for all nerve injuries, and that altering κ opioid levels can affect glutaminergic pathways at a substantially later time.
Child care instability from 6 to 36 months and the social adjustment of children in prekindergarten

Abstract Most children in the United States experience nonparental child care during early childhood, and many children experience changes in their care during this period. Changes in care, or child care instability, have been argued to disrupt children's emerging relationships with others and may impede children's social-emotional development, particularly when changes occur during infancy and toddlerhood. Data for this study were drawn from the Family Life Project, a longitudinal study representative of families living in rural low-wealth areas. With a sample of 1292 children who were followed from six months to prekindergarten, this study examined the associations between cumulative child provider instability (measured as overall changes or changes across or within settings) from 6 to 36 months and children's social adjustment at prekindergarten. A number of factors were included to control for family selection into child care. Results suggested that more overall child care provider instability was negatively associated with teacher ratings of social adjustment at prekindergarten. This association was driven by provider instability across but not within settings, though effect sizes were small. These findings point to an increased need to understand how early child care instability may be related to children's subsequent development.
Least-Squares Analysis of the Film-Substrate Problem in Ellipsometry*†

We have found that the thickness and refractive indices for the film–substrate problem in ellipsometry can frequently be calculated with a least-squares technique. It is shown that one algorithm can be used with a variety of data to solve problems that were formerly solved with step-by-step searches through parameter space. Moreover, the least-squares technique leads to a statistically meaningful estimate of the variances of the parameters. It is shown that the variances obtained from a correct error analysis can be at least one hundred times as large as those obtained from a naive analysis. It is also shown how the error analysis can provide information that is helpful in deciding if a given experiment is worthwhile.
Light scattering measurements of energy partitioning in laser air sparks

Laser light scattering provides a powerful diagnostic of plasmas and fluids in the form of Thomson and Rayleigh scattering1. In this work, we present time and space resolved collective Thomson scattering measurements of T e and n e in the plasma core of atmospheric pressure air sparks generated with a 10ns pulse, 1064nm Nd:YAG laser. In the shockwave region, a combination of Rayleigh scattering and Filtered Rayleigh scattering are used to spatially and temporally resolve temperature, radial velocity and density. Filtered Rayleigh scattering is a technique whereby scattered light is spectrally filtered by an atomic or molecular gas to indirectly extract line shape information. These measurements cover a laser energy range of 30mJ to 100mJ and a temporal duration of 1–5µs after spark formation.
Predicting Reliability of LSI Printed Circuit Carriers

The arrival of Large Scale Integration (LSI) devices forced the development of products which could reliably package these high density chip carriers. Until LSI, printed circuit technology designers were only moderately challenged to make high density products. This change occurred in the early 1970s at IBM with the printed circuit packaging for the IBM 4300 models. This was the first system application of LSI chip carriers. Since then, numerous LSI printed circuit carrier designs have been used in IBM systems. The methods to predict reliability of the LSI printed circuit carriers have not kept up with the hardware technology. This paper will describe an enhanced method of prediction which more closely represents the performance of today's LSI printed circuit cards and mother boards. Computer processed algorithms will be used to estimate the failure rates of a particular printed circuit carrier and the effects of this estimate on the complete system will be discussed. The estimation algorithms are contained in programmes resident on floppy diskettes and run on an IBM Personal Computer. The flexibility and ease of use of the PC allows the user to make any necessary additions or changes to the algorithms quickly. The algorithms are derived from standard Weibull reliability techniques but include internally derived factors which enhance the accuracy of the Weibull predictions. Data from extensive field reporting of any defects and detailed failure analysis are used to enhance the accuracy of the algorithms. Using the enhanced algorithms, one can generate new estimates easily. Quick access and fast turnaround times result in a convenient and cost effective technique to provide these estimates to system users on a timely basis. Design changes to the carrier which could affect the reliability are quickly modelled in the algorithms and new reliability estimates are provided allowing the final user to make the required system trade‐offs easily. These design changes and new reliability projections can be presented to management in a timely manner and allow them to make the cost/performance decisions which result in the optimum marketable product.
Valuation and Accounting for Inflation and Foreign Exchange

Inflation and foreign exchange raise new issues with respect to accounting representations of equity value. For example, inflation creates an earnings illusion as an artifact of the mismatching of expenses based on allocations of historical costs with current revenues in determining earnings. This mismatching distorts mappings of aggregate earnings and book values into equity value such that value-relevant information is lost. In this article we consider the consequences of inflation and foreign exchange accounting policies, including those contained in accounting standards, on the value relevance of bottom-line accounting numbers. Policies are identified that achieve efficient accounting in the sense that aggregate (comprehensive) earnings and book values are sufficient for an accounting representation of equity value. The linear relations that emerge provide predictions on capitalization coefficients that help explain results of empirical inquiries. As well, our analysis provides a theoretical foundation for policies contained in accounting standards that contributes to the resolution of controversies such as that concerning foreign exchange accounting.
Comparative studies of antilymphocyte, antipolynucleotide, and antiviral antibodies among families of patients with systemic lupus erythematosus

Antilymphocyte, antipolynucleotide, and antiviral antibodies in 15 Soviet systemic lupus erythematosus (SLE) probands and their 41 relatives were compared with those in 57 members of 15 control Russian families. Seventy-eight and three-tenths percent of SLE relatives were positive for antilymphocyte antibody versus 26.3% positive reactions in controls. Antipolynucleotide antibody closely paralleled antilymphocyte antibody in both groups. Antiviral antibody was significantly increased in SLE relatives as compared to control family members. No correlation was noted between quantitative IgG, IgA, or IgM levels and various antibodies studied.
Synthesis and cellular effects of cycloterpenals: cyclohexadienal-based activators of neurite outgrowth.

Abstract An unusual class of diterpenoid natural products, ‘cycloterpenals’ (with a central cyclohexadienal core), that arise in nature by condensation of retinoids and other isoprenes, have been isolated from a variety of organisms including marine sponges as well as from the human eye. A milk whey protein has also demonstrated the formation of a cycloterpenal derived from β-ionylidineacetaldehyde. Here, we generate a synthetic library of these molecules where we detail reaction conditions required to effect cross condensation of α,β-unsaturated aldehydes as opposed to homodimerization. The ability of this class of molecules to activate neurite outgrowth activity is reported.
Complications following endoscopic intracranial procedures in children

Background The significant technological improvement of endoscopic instrumentation has allowed, in the last 10 years, a widespread diffusion of neuroendoscopic procedures. Nevertheless, severe, sometimes life-threatening, complications may occur during neuroendoscopic surgery, and the incidence and age specificity of complications in children have been underdescribed so far.
Protein-Mediated Antagonism between HIV Reverse Transcriptase Ligands Nevirapine and MgATP

Nonnucleoside reverse transcriptase inhibitors (NNRTIs) play a central role in the treatment of AIDS, but their mechanisms of action are incompletely understood. The interaction of the NNRTI nevirapine (NVP) with HIV-1 reverse transcriptase (RT) is characterized by a preference for the open conformation of the fingers/thumb subdomains, and a reported variation of three orders of magnitude between the binding affinity of NVP for RT in the presence or absence of primer/template DNA. To investigate the relationship between conformation and ligand binding, we evaluated the use of methionine NMR probes positioned near the tip of the fingers or thumb subdomains. Such probes would be expected to be sensitive to changes in the local environment depending on the fractions of open and closed RT. Comparisons of the NMR spectra of three conservative mutations, I63M, L74M, and L289M, indicated that M63 showed the greatest shift sensitivity to the addition of NVP. The exchange kinetics of the M63 resonance are fast on the chemical shift timescale, but become slow in the presence of NVP due to the slow binding of RT with the inhibitor. The simplest model consistent with this behavior involves a rapid open/closed equilibrium coupled with a slow interaction of the inhibitor with the open conformation. Studies of RT in the presence of both NVP and MgATP indicate a strong negative cooperativity. Binding of MgATP reduces the fraction of RT bound to NVP, as indicated by the intensity of the NVP-perturbed M230 resonance, and enhances the dissociation rate constant of the NVP, resulting in an increase of the open/closed interconversion rate, so that the M63 resonance moves into the fast/intermediate-exchange regime. Protein-mediated interactions appear to explain most of the affinity variation of NVP for RT.
Dietary pyridoxine interaction with tryptophan or histidine on brain serotonin and histamine metabolism

Abstract We studied the metabolic effects of high dietary intakes of pyridoxine and of the substrate-cofactor interaction between dietary histidine or tryptophan and pyridoxine in rat brain. In the substrate-cofactor interaction study, histamine and serotonin levels were determined in rats fed elevated or requirement levels of substrate (histidine: 0.3% and 0.8%, tryptophan: 0.15% and 0.6%) and excess or requirement levels of pyrodoxine HCl (7 mg vs. 3,000 mg/kg). Excess pyridoxine intake caused a differential effect on brain histamine concentration—inhibitory with the requirement level of histidine (−29%), and stimulatory (+21%) with the elevated level of histidine. When dietary tryptophan was fed at the requirement level, excess pyridoxine caused essentially no changes in hypothalamic serotonin and 5HIAA (−2%, −2%). With elevated tryptophan intake, excess pyridoxine significantly increased serotonin and 5HIAA (+32%, +20%) in the hypothalamus. These results indicate a clear interaction between substrate and coenzyme precursor which influences brain metabolism of histamine and serotonin.
An Epidemiological Study of Hirschsprung's Disease

All newly diagnosed cases of Hirschsprung's Disease among children born in Baltimore City and County, Maryland and diagnosed within the Baltimore Standard Metropolitan Area during 1969 through 1977 were identified. Using hospital records and death certificates, 33 cases were ascertained. An overall incidence rate of 18.6 per 100 000 livebirths was found, similar to that reported by others. A high male to female ratio (4.32:1) was found; the ratio for non-whites to whites was 1.67:1. Non-white males had the highest rate, 37.6 per 100 000 livebirths. These findings plus the fact that 9% of these children were also diagnosed as having Down's Syndrome, were evidence that the aetiology of Hirschsprung's Disease may be partially genetic. Among environmental factors studied, there was no time trend and no relationship with socioeconomic status found. Among whites, there was a larger percentage of children who were the first births of mothers aged 30 and above, a result previously reported for children with neural tube defects. Very little is known about micro-environmental factors in relation to Hirschsprung's Disease and this would seem to be the area for future emphasis in research.
Cholinergic modulation of multivesicular release regulates striatal synaptic potency and integration

In the striatum, acetylcholine modulates glutamate release via muscarinic receptors. The authors examine individual synapses in rat striatum and find that glutamatergic afferents show multivesicular release and low postsynpatic receptor saturation. Acetylcholine decreases both the probability of release and the amount of glutamate in the cleft, thereby suppressing the activation of nonlinearities in dendrites. The pleiotropic actions of neuromodulators on pre- and postsynaptic targets make disentangling the mechanisms underlying regulation of synaptic transmission challenging. In the striatum, acetylcholine modulates glutamate release via activation of muscarinic receptors (mAchRs), although the consequences for postsynaptic signaling are unclear. Using two-photon microscopy and glutamate uncaging to examine individual synapses in the rat striatum, we found that glutamatergic afferents have a high degree of multivesicular release (MVR) in the absence of postsynaptic receptor saturation. We found that mAchR activation decreased both the probability of release and the concentration of glutamate in the synaptic cleft. The corresponding decrease in synaptic potency reduced the duration of synaptic potentials and limited temporal summation of afferent inputs. These findings reveal a mechanism by which a combination of basal MVR and low receptor saturation allow the presynaptic actions of a neuromodulator to control the engagement of postsynaptic nonlinearities and regulate synaptic integration.
International Cooperation to Protect the Marine Environment: The Case of Radioactive Waste Disposal

Since 1958 a number of international controls have been developed for dumping of radioactive wastes at sea. Increased dumping, discharge of reprocessing effluents, and potential ocean emplacement of high level wastes call for improved organizational and technical measures.
Model order-reduction of RC(L) interconnect including variational analysis

As interconnect feature sizes continue to scale to smaller dimensions, long interconnect can dominate the IC timing performance, but the interconnect parameter variations make it difficult to predict these dominant delay extremes. This paper presents a model order-reduction technique for RLC interconnect circuits that includes variational analysis to capture manufacturing variations. Matrix perturbation theory is combined with dominant-pole-analysis and Krylov-subspace-analysis methods to produce reduced-order models with direct inclusion of statistically independent manufacturing variations. The accuracy of the resulting variational reduced-order models is demonstrated on several industrial examples.