cssi/SciSciGPT-SciSciNet huggingface dataset:
Robotic production of 2-deoxy-2-[18F]fluoro-D-glucose: a routine method of synthesis using tetrabutylammonium [18F]fluoride.

Abstract Using existing robotic hardware and software programs developed for the synthesis of several positron-emitting radiopharmaceuticals for PET imaging [Brodack et al. (1988) Appl. Radiat. Isot.39, 689], the additional automated synthesis of 2-deoxy-2-[18F]fluoro- d -glucose (2-[18F]FDG) has been incorporated into our Zymate Laboratory Automation System. The robotic synthesis of 2-[18F]FDG took less than one week to implement, including the organization of software subroutines and construction of an additional heating station. The end of synthesis yield (12–17%) and radiochemical purity (96–99%) for the robotic preparation of 2-[18F]FDG is similar to that of the manual synthesis. This automated method uses anhydrous tetrabutylammonium [18F]fluoride as the reactive fluoride source in the labeling step. The procedure is a modification of the synthesis reported by Hamacher et al. [Hamacher et al. (1986) J. Nucl. Med.27, 235].
A comparison of methods for the analysis of event-related potentials in deception detection

We previously reported that a Bayesian-based event-related potential memory assessment procedure (Allen, Iacono, & Danielson, 1992, Psychophysiology, 29, 504-522) was highly accurate at identifying previously learned material, regardless of an individual's motivational incentive to conceal information. When a bootstrapping procedure (Farwell & Donchin, 1991, Psychophysiology, 28, 531-547) is applied to these same data, greater motivational incentives appear to increase the accuracy of the procedure. Receiver operating characteristic (ROC) curves were used to examine these two procedures and a new procedure. ROC curves indicated that all three methods produce extremely high rates of classification accuracy and that the sensitivity of the bootstrapping procedure to motivational incentive is due to the particular cut points selected. One or the other method may be preferred depending upon incentive to deceive, the cost of incorrect decisions, and the availability of extra psychophysiological data.
Inhibition of cell-free foot-and-mouth disease virus-ribonucleic acid synthesis by antibody

Abstract The cell-free synthesis of virus specific RNA by foot-and-mouth disease virus (FMDV) RNA polymerase was inhibited by antisera from infected guinea pigs and cattle, by γ-globulin fractions from sera of infected guinea pigs, and by antibody isolated from antibody-antigen precipitates. Deoxycholate, at a concentration of 0.5%, increased the inhibitory effect from 20% to 90%. Ribonucleic acid profiles of antibody-inhibited enzyme products showed a small peak corresponding to 20 S RNase-resistant material and no 37 S viral RNA peak as usually seen in the in vitro deoxycholate pattern. Antisera from animals vaccinated with inactivated virus, which differed from that obtained by infection in not possessing antibody to a third antigenic component, did not inhibit polymerase activity. This third antigenic component was previously found to be a nonviral constituent associated with infection. Preparations of antisera from infected animals from which antibody to this antigen had been removed in stepwise amounts, showed corresponding decreases in inhibition of polymerase activity. Polymerases from FMDV types A and O appeared to be immunologically related, whereas that from type SAT 2 did not. The evidence indicates that FMDV-RNA polymerase may be the third antigenic component.
Analysis and control of monolithic piezoelectric nano-actuator

This paper describes the analysis and control of a two degree-of-freedom (DOF) monolithic piezoelectric actuator. This actuator is part of a six-DOF manipulator capable of linear resolution to 2 nm and angular resolution to 1 arc-second. Design of this actuator differs from the existing ones in that it has a monolithic structure which enables a high bandwidth, low drift, and high force realization. A number of nonlinearities exist in the actuator, stemming from the geometry and material properties. For example, coupling of the actuator elements can be modeled as a soft spring which increases displacement/drive-voltage gain (scale factor) at high actuation levels. In this work, a combination of feedforward (amplitude-dependent command prefiltering/input shaping) and feedback control are applied to reduce the effects of 1) scale factor nonlinearities; 2) hysteresis; and 3) output oscillations.
Toward an ice‐free Arctic ocean

The strong salinity stratification of the Arctic Ocean prevents substantial ice-free conditions in winter by suppressing convection and reducing upward heat flux from the Atlantic Water. These conditions would be significantly altered in the sensitive southern Eurasian basin if suggested diversions of western Siberian rivers were accomplished.
Conformation of Prostaglandins

ALTHOUGH different prostaglandins* may have different pharmacological effects, in general the compounds have the same qualitative action on a given cell type. Investigation1,2 has revealed structure-activity correlations and the importance of the orientation of the 11 and 15 hydroxyl groups3 is recognized. Molecular model building together with structure-activity data have suggested that prostaglandins are one of a number of classes of drugs and hormones that seem to fit stereochemically into a pre-existing (for example, polypeptide-nucleotide) receptor site4,5. The restraints applied to the prostaglandin molecule to fix it as a stable conformational isomer, or conformer, are little understood and we now wish to indicate the significance of this conformation with respect to interaction with biological membranes.
The Alpha Project

One goal of systems biology is to understand how genome-encoded parts interact to produce quantitative phenotypes. The Alpha Project is a medium-scale, interdisciplinary systems biology effort that aims to achieve this goal by understanding fundamental quantitative behaviours of a prototypic signal transduction pathway, the yeast pheromone response system from Saccharomyces cerevisiae. The Alpha Project distinguishes itself from many other systems biology projects by studying a tightly bounded and well-characterised system that is easily modified by genetic means, and by focusing on deep understanding of a discrete number of important and accessible quantitative behaviours. During the project, the authors have developed tools to measure the appropriate data and develop models at appropriate levels of detail to study a number of these quantitative behaviours. The authors have also developed transportable experimental tools and conceptual frameworks for understanding other signalling systems. In particular, the authors have begun to interpret system behaviours and their underlying molecular mechanisms through the lens of information transmission, a principal function of signalling systems. The Alpha Project demonstrates that interdisciplinary studies that identify key quantitative behaviours and measure important quantities, in the context of well-articulated abstractions of system function and appropriate analytical frameworks, can lead to deeper biological understanding. The authors' experience may provide a productive template for systems biology investigations of other cellular systems.
Nanoparticle-loaded encapsulation materials for light-emitting diode applications

Nanoparticle-loaded encapsulants provide unique optical and material properties for the enhancement of light extraction efficiency in light-emitting diodes (LEDs). We report on the uniform dispersion of TiO2 nanoparticles with average diameter of 40 nm in epoxy, and the demonstration of a refractive index (n)of 1.68 at 400 nm wavelength, higher than that of pure epoxy (n = 1.53). It is found that proper chemical surfactants and nanoparticle preparation are critical to eliminate agglomeration of nanoparticles. Theoretical analysis of optical scattering in nanoparticle-loaded encapsulation materials reveals that although the size and loading factor of nanoparticles greatly influence scattering, specular transparency of the encapsulant film occurs if the thicknesses of the films are kept below the optical scattering length. Furthermore, the encapsulants benefit from an optimized scattering coefficient as demonstrated by three-dimensional ray-tracing simulations showing light extraction efficiency enhancements greater than 50%.
The PVT properties of water. V. The fluid to 1 kbar at 350-500°C and along the saturation line from 150 to 350°C

The density of water has been measured from low pressures to 1 kbar (1 bar = 10 5 Pa) at 25 K intervals from 350 to 500 °C and the density change on condensation has been measured from 150 to 350 °C by injecting water into a 35 cm 3 high-temperature vessel that can be completely filled in a single delivery from the screw injector used in earlier work. The thermal expansion of the vessel was determined by a gas-expansion method. The estimated uncertainty caused by the uncertainty of the volume of the vessel at low pressure is 0.02 kg m -3 at 150 °C and 0.08 kg m -3 at all other temperatures, and the uncertainty arising from the uncertainty in the compression of the vessel is 0.10 kg m -3 kbar -1 .
Human vasoactive hormone adrenomedullin and its binding protein rescue experimental animals from shock.

Abstract We recently discovered that vascular responsiveness to adrenomedullin (AM), a vasoactive hormone, decreases after hemorrhage, which is markedly improved by the addition of its binding protein AMBP-1. One obstacle hampering the development of AM/AMBP-1 as resuscitation agents in trauma victims is the potential immunogenicity of rat proteins in humans. Although less potent than rat AM, human AM has been shown to increase organ perfusion in rats. We therefore hypothesized that administration of human AM/AMBP-1 improves organ function and survival after severe blood loss in rats. To test this, male Sprague–Dawley rats were bled to and maintained at an MAP of 40 mmHg for 90 min. They were then resuscitated with an equal volume of shed blood in the form of Ringer's lactate (i.e., low-volume resuscitation) over 60 min. At 15 min after the beginning of resuscitation, human AM/AMBP-1 (12/40 or 48/160 μg/kg BW) were administered intravenously over 45 min. Various pathophysiological parameters were measured 4 h after resuscitation. In additional groups of animals, a 12-day survival study was conducted. Our result showed that tissue injury as evidenced by increased levels of transaminases, lactate, and creatinine, was present at 4 h after hemorrhage and resuscitation. Moreover, pro-inflammatory cytokines TNF-α and IL-6 were also significantly elevated. Administration of AM/AMBP-1 markedly attenuated tissue injury, reduced cytokine levels, and improved the survival rate from 29% (vehicle) to 62% (low-dose) or 70% (high-dose). However, neither human AM alone nor human AMBP-1 alone prevented the significant increase in ALT, AST, lactate and creatinine at 4 h after the completion of hemorrhage and resuscitation. Moreover, the half-life of human AM and human AMBP-1 in rats was 35.8 min and 1.68 h, respectively. Thus, administration of human AM/AMBP-1 may be a useful approach for attenuating organ injury, and reducing mortality after hemorrhagic shock.
Position 127 amino acid substitutions affect the formation of CRP:cAMP:lacP complexes but not CRP:cAMP:RNA polymerase complexes at lacP.

The lacP DNA binding and activation characteristics of CRP having amino acid substitutions at position 127 were investigated. Wild-type (WT) and T127C CRP footprinted lacP DNA in the presence of DNase I in a cAMP-dependent manner. The T127G, T127I, and T127S forms of CRP failed to footprint lacP both in the absence and in the presence of cAMP. Consistent with these data, WT and T127C CRP:cAMP complexes exhibited high affinity for the lacP CRP site whereas T127G, T127I, or T127S CRP:cAMP complexes exhibited low affinity for the lacP CRP site. CRP:cAMP:RNA polymerase (RNAP) complexes formed at lacP in reactions that contained WT, T127C, T127G, T127I, or T127S CRP. These results demonstrate that allosteric changes important for cAMP-mediated CRP activation are differentially affected by amino acid substitution at position 127. Proper cAMP-mediated reorientation of the DNA binding helices required either threonine or cysteine at position 127. However, cAMP-dependent interaction of CRP with RNAP was accomplish...
Distinct roles for Cav2.1-2.3 in activity-dependent synaptic dynamics.

Synaptic transmission throughout most of the CNS is steeply dependent on presynaptic calcium influx through the voltage-gated calcium channels Cav2.1–Cav2.3. In addition to triggering exocytosis, this calcium influx also recruits short-term synaptic plasticity. During the complex patterns of presynaptic activity that occur in vivo, several forms of plasticity combine to generate a synaptic output that is dynamic, in which the size of a given excitatory postsynaptic potential (EPSP) in response to a given spike depends on the short-term history of presynaptic activity. It remains unclear whether the different Cav2 channels play distinct roles in defining these synaptic dynamics and, if so, under what conditions different Cav2 family members most effectively determine synaptic output. We examined these questions by measuring the effects of calcium channel-selective toxins on synaptic transmission at the Schaffer collateral synapse in hippocampal slices from adult mice in response to both low-frequency stimulation and complex stimulus trains derived from in vivo recordings. Blockade of Cav2.1 had a greater inhibitory effect on synaptic transmission during low-frequency components of the stimulus train than on synaptic transmission during high-frequency components of the train, indicating that Cav2.1 had a greater fractional contribution to synaptic transmission at low frequencies than at high frequencies. Relative to Cav2.1, Cav2.2 had a disproportionately reduced contribution to synaptic transmission at frequencies >20 Hz, while Cav2.3 had a disproportionately increased contribution to synaptic transmission at frequencies >1 Hz. These activity-dependent effects of different Cav2 family members shape the filtering characteristics of GABAB receptor-mediated presynaptic inhibition. Thus different Cav2 channels vary in their coupling to synaptic transmission over different frequency ranges, with consequences for the frequency tuning of both synaptic dynamics and presynaptic neuromodulation.
Barriers to Flow: The Effects of Experimental Cage Structures on Water Velocities in High-energy Subtidal and Intertidal Environments

Abstract For decades, marine ecologists have used cages as biological enclosure or exclosure devices to manipulate movement, growth, and survival of organisms. The ability to control the densities of focal organisms makes these structures a powerful tool. However, cages can often produce artifacts that influence the outcome of experiments. Although a subset of these artifacts have been examined previously, the effects of cages on water motion have not been adequately addressed from a quantitative standpoint, especially in high-flow environments. We targeted this data gap by explicitly measuring the fractional degree of velocity reduction inside a variety of experimental cage structures across flow conditions spanning those typical of wave-swept shallow subtidal and intertidal zones. Cages decreased velocities inside by up to 47% and reduced high-energy impact forces by more than 40%. Associated cage controls, employed to mimic physical effects of cages without interfering with organism movement, often had effects on water flow similar to those of cages. However, the nearly half an order of magnitude change in velocities inside cages and their controls reveals the need to be vigilant in considering potential artifacts, especially those tied to secondary biological interactions. These artifacts may be reduced by maximizing mesh size, employing large plot sizes and low profile structures, using cage controls that best mimic effects of the full cage, and monitoring cage controls to avoid the establishment of high-density “consumer hotels” within them. Using such approaches, researchers can minimize experimental biases and simplify the explanation of experimental results.
Scaling pigeons' choice of feeds: bigger is better

Preferences of hungry pigeons among 10 grains and pellets were analyzed using a Thurstone scaling procedure. The recovered scales were positively correlated with size of the feed. The correlations improved when the Thurstonian assumption of equal-sized discriminal dispersions (Case V) was replaced with the assumption of proportional-sized dispersions (Case VI), as entailed by Weber's law. The correlations weakened when the experiments were conducted with the pigeons close to their free-feeding weights, where the probability of sampling alternative grains increased. In the final experiment, exposure to a large pellet shifted the preferences between two smaller pellets.
Hypoglycemia as a provocative test of prolactin release

Abstract Insulin-induced hypoglycemia has been traditionally used to test growth hormone (GH) and cortisol reserve. In order to determine its usefulness as a provocative test for prolactin (PRL) release, 31 healthy men and women, 38 patients with definite pituitary abnormalities (pituitary tumors, 17; hypopituitarism [other causes]—complete, 4, or partial, 17), and 17 patients with suspected pituitary dysfunction (delayed puberty, 5; short stature, 4; secondary amenorrhea, 6; empty sella, 2, received regular i.v. insulin (0.05–0.15 U/kg), and the plasma was assayed serially for PRL, GH, cortisol, and glucose. In the 31 healthy subjects, PRL increased from 16.3 ± 1.8 ng/ml (mean ± SEM) to 45.5 ± 7.9 (p
Calnexin Associates with Monomeric and Oligomeric (Disulfide-linked) CD3δ Proteins in Murine T Lymphocytes

The antigen-binding receptor expressed on most T lymphocytes consists of disulfide-linked clonotypic alphabeta heterodimers noncovalently associated with monomeric CD3gamma,delta,epsilon proteins and disulfide-linked zeta zeta homodimers, collectively referred to as the T cell antigen receptor (TCR) complex. Here, we examined and compared the disulfide linkage status of newly synthesized TCR proteins in murine CD4(+)CD8(+) thymocytes and splenic T cells. These studies demonstrate that CD3delta proteins exist as both monomeric and oligomeric (disulfide-linked) species that differentially assemble with CD3epsilon subunits in CD4(+)CD8(+) thymocytes and splenic T cells. Interestingly, unlike previous results on glucose trimming and TCR assembly of CD3delta proteins in splenic T cells (Van Leeuwen, J. E. M., and K. P. Kearse (1996) J. Biol. Chem. 271, 9660-9665), we found that glucose residues were not invariably removed from CD3delta glycoproteins prior to their assembly with CD3epsilon subunits in CD4(+)CD8(+) thymocytes. Finally, these studies show that calnexin associates with both monomeric and disulfide-linked CD3delta proteins in murine T cells. The data in the current report demonstrate that CD3delta proteins exist as both monomeric and disulfide-linked molecules in murine T cells that differentially associate with partner TCR chains in CD4(+)CD8(+) thymocytes and splenic T cells. These results are consistent with the concept that folding and assembly of CD3delta proteins is a function of their oxidation state.
Solution structure of a DNA duplex containing a guanine-difluorotoluene pair: a wobble pair without hydrogen bonding?

The incorporation of synthetic nucleoside analogues into DNA duplexes provides a unique opportunity to probe both structure and function of nucleic acids. We used 1H and 19F NMR and molecular dynamics calculations to determine the solution structures of two similar DNA decamer duplexes, one containing a central G-T mismatched or “wobble” base pair, and one in which the thymine in this base pair is replaced by difluorotoluene (a thymine isostere) creating a G-F pair. Here, we show that the non-hydrogen-bonding G-F pair stacks relatively well into the helix and that the distortions caused by each non-Watson−Crick G-T or G-F base pair are quite localized to a three base pair site around the mismatch. A detailed structural analysis reveals that the absence of hydrogen bonding introduces more dynamic motion into the G-F pair relative to G-T and permits the G-F pair to exhibit stacking and conformational features characteristic of both a Watson−Crick base pair (on the guanine containing strand) and a wobble bas...
A flexible loop in tyrosine hydroxylase controls coupling of amino acid hydroxylation to tetrahydropterin oxidation.

The role of a polypeptide loop in tyrosine hydroxylase (TyrH) whose homolog in phenylalanine hydroxylase (PheH) takes on a different conformation when substrates are bound has been studied using site-directed mutagenesis. The loop spans positions 177 to 191; alanine was introduced into those positions, introducing one alanine substitution per TyrH variant. Mutagenesis of residues in the center of the loop resulted in alterations in the KM values for substrates, the Vmax value for dihydroxyphenylalanine (DOPA) synthesis, and the coupling of tetrahydropterin oxidation to tyrosine hydroxylation. The variant with the most altered KM value for 6-methyltetrahydropterin was TyrH F184A. The variants with the most affected Ktyr values were those with substitutions in the center of the loop, TyrH K183A, F184A, D185A, P186A and D187A. These five variants also had the most reduced Vmax values for DOPA synthesis. Alanine substitution in positions 182–186 resulted in lowered ratios of tyrosine hydroxylation to tetrahydropterin oxidation. TyrH F184Y and PheH Y138F, variants with the residue at the center of the loop substituted with the residue present at the homologous position in the other hydroxylase, were also studied. The V/Ktyr to V/Kphe ratios for these variants were altered significantly, but the results did not suggest that F184 of TyrH or Y138 of PheH plays a dominant role in determining amino acid substrate specificity.
Perceived spatial frequency varies with stimulus duration.

A sinusoidal grating appears of higher spatial frequency when briefly flashed than when presented for longer durations. This effect is restricted to gratings of low spatial frequency (1 cycle/deg). Time-dependent changes in the response of spatial frequency channels are a likely cause.
Isotope Shift in λ5556 Å of Ytterbium i

Enriched isotopic samples were excited in a liquidnitrogen-cooled hoilow- cathode discharge tube, with neon as the carrier gas. Spectrograms were obtained with a Fabry-Perot interferometer mounted externally to a Hilger E-495 spectrograph. The center-of-gravity locations for the odd isotopes were inciuded. All values were iisted relative to the 174 isotope. The even isotopes showed an increasing shift as neutron pairs were subtracted. The two lightest isotopic pairs showed an appreciably larger shift than the two heavier isotopic pairs. (C.E.S.)
Future Requirements of Modeling Software for Integrated Optical Communication Systems

As silicon photonics processes mature and become available to an ever growing user base, the infrastructure needed to support large scale design needs to follow suit. We discuss here future requirements for modeling of integrated optical communication systems.
Northeast Pacific iron distributions in relation to phytoplankton productivity

Dissolved and particulate Fe concentrations, measured at three deep ocean stations on a 1600 km inshore-offshore VERTEX transect, were compared with those found at four shallow California continental margin stations. The three VERTEX profiles shared similar features: very low dissolved Fe levels (<0.1 nmol kg−1) in surface waters, increasing amounts with depth, and maxima (∼1.0–1.3 nmol kg−1) in association with the oxygen minimum. In contrast, concentrations as high as 9 nmol kg−1 of dissolved Fe were found at the shallow margin stations, in association with elevated levels of Mn (17 nmol kg−1) and Co (200 pmol kg−1). Inshore and offshore Fe distributions were evaluated in relation to the phytoplankton's requirement for this essential element. Local shelf diagenetic Fe input appears to be adequate for phytoplankton growth even in environments where increased demand results from the upwelling of major nutrients. However, the Fe laterally mixed out into the ocean's interior within the oxygen minimum and supplied to the surface via vertical mixing processes provides only a few percent of open ocean phytoplankton demand; the other 95% must be provided by atmospheric input. We also consider environments in which Fe supplies may be limiting phytoplankton growth; i.e. surface waters of the Subarctic and Antarctic, where major nutrients are never depleted. We postulate that atmospheric Fe input rates are not high enough to meet the elevated phytoplankton demand resulting from offshore major nutrient upwelling. As a result, major nutrient depletion occurs only along continental margins and ice edges, where Fe supplies should be adequate. Atmospheric dust concentrations were one to two orders of magnitude higher in glacial times than those in the present and last interglacial periods. The lower glacial atmospheric CO2 levels, which resulted from the increased biological utilization of major nutrients at high latitudes, may have been stimulated by the enhanced availability of atmospheric Fe.
The effect of growth retardants on anthocyanin production in carrot cell suspension cultures.

The effect of growth retardants on anthocyanin production was studied in wild carrot (Daucus carota) cell suspension cultures. Paclobutrazol [(2RS,3RS) — 1 — (4-chlorophenyl) — 4,4 —dimethyl-2-(1,2,4-triazol-1-yl) pentan-3-ol], uniconazole [(E)-1-(4-chlorophenyl-4,4 —) dimethyl-2-(1,2,4-triazol-1-yl)-1-penten-3-ol], tetcyclacis [5-(4-chloro-phenyl) -3,4,5,9,10-pentaaza-tetracyclo-5, 4, 102,6, O8,11 — dodeca-3, 9-diene], ancymidol [α-cyclopropyl — 4 — methoxy-α(pyrimidine-5-yl)benzyl alcohol] and CCC (2-chloro-ethyltrimethylammonium chloride) increased anthocyanin accumulation. AMO-1618 [(2-isopropyl-5-methyl-4-trimethyl-ammonium-chloride)-phenyl-1-piperidinium carboxylate] did not increase anthocyanin accumulation in the first passage but did increase it during the second passage on medium for improved anthocyanin accumulation. Prohexadione (3,5-dioxo-4-propionylcyclohexane carboxylic acid) decreased anthocyanin accumulation by 10%–12.5%.
Evaluation of the Performance Characteristics and Modeling of an Alkaline Fuel Cell

Alkaline fuel cells are one of the low cost types of fuel cells. In this contribution, the performance of an alkaline fuel cell was investigated by varying different operational parameters. The cell was tested under four different electrolyte concentrations and three different levels of anode flow rates. The results of the test revealed that the efficiency of the cell increases with the increase in electrolyte concentration. Anode flow rate was not found to have a considerable impact on the cell performance. Impedance spectroscopy has been conducted to validate the mathematical model and further investigate ohmic resistance, anode and cathode activation losses and mass transport losses. The optimal level of electrolyte concentration and anode flow rate for an alkaline fuel cell has been deduced through modeling & statistical analysis.Copyright © 2009 by ASME
Complications and outcomes after spinal cord tumor resection in the United States from 1993 to 2002.

Complications and outcomes after spinal cord tumor resection in the United States from 1993 to 2002
Properties and distribution of TRH receptors in normal and spastic mutant mouse brain and spinal cord.

Specific binding sites for thyrotropin-releasing hormone (TRH) were labelled with the potent analog, [(3)H] (3-Me-His(2))TRH, in the brain and spinal cord of the mutant mouse spastic and nonafflicted littermate controls. Equilibrium binding parameters determined from competition assays indicated dissociation constant (K(d)) of 4-5 nM in selected regions of the brain in both groups of animals. Detailed examination of the TRH receptor density at 1 nM [(3)]MeTRH concentration revealed a marked heterogeneous distribution (amygdala hippocampus = n. accumbens/striatum ? midbrain > spinal cord > pons/medulla = hypothalamus ? cerebellum) . An almost identical anatomical localization profile of TRH receptors was apparent in control and spastic mice. The pharmacological specificity of [(3)H]MeTRH binding sites in the spinal cord and amygdala of these animals was again closely similar and resembled that documented previously for other mammalian species. In conclusion, TRH receptors in spastic mutant mice exhibit similar properties and brain regional distribution as their normal counterparts.
Synthesis approach for bidirectional associative memories based on the perceptron training algorithm

Abstract Bidirectional associative memories are being used extensively for solving a variety of problems related to pattern recognition. In the present paper, a new synthesis approach is developed for bidirectional associative memories using feedback neural networks. The synthesis problem of bidirectional associative memories is formulated as a set of linear inequalities which can be solved using the perceptron training algorithm. To demonstrate the applicability of the present results, a specific example is considered.
DNA conformational kinetics.

A model for the time dependence of DNA conformational state probabilities is formulated in the form of first-order differential equations. This model is applied to investigate the renaturation and denaturation rates for T2 and T7 DNA as reported in the series of experiments by Record and Zimm. Qualitative agreement is found in denaturation and for series of renaturation experiments with the same initial condition. However, partial agreement with series of renaturation experiments having the same final condition is obtained only by including an initial bimolecular step with properly matched pairs of strands. Comparison of all experiments with the calculated rates yields 5 × 104 min−1 as the step rate for melting a single base pair.
Online visual tracking with histograms and articulating blocks

We propose an algorithm for accurate tracking of articulated objects using online update of appearance and shape. The challenge here is to model foreground appearance with histograms in a way that is both efficient and accurate. In this algorithm, the constantly changing foreground shape is modeled as a small number of rectangular blocks, whose positions within the tracking window are adaptively determined. Under the general assumption of stationary foreground appearance, we show that robust object tracking is possible by adaptively adjusting the locations of these blocks. Implemented in MATLAB without substantial optimization, our tracker runs already at 3.7 frames per second on a 3GHz machine. Experimental results have demonstrated that the algorithm is able to efficiently track articulated objects undergoing large variation in appearance and shape.
Social aspects of solid wastes development and management: Refuse, recovery, and reuse

The paper examines the ‘throwaway’ cultural heritage, expressed not only in the vast amounts of solid waste generated, but also in the public attitudes towards unwanted residues. An attempt is made to contrast cultural perceptions of solid waste management (juxtaposing the U.S. with other cultures) and the extent to which a network of values has been created with heavy dependence in the generation of waste. In examining larger social trends and emerging life styles a distinction is made between corrective solutions (disposal) and preventive approaches, i.e., materials flow and residuals management. This implies a new ethos where rather than continually trying to ‘bury’ waste, the culture and economy is re-directed towards a non-generation of waste and towards a transformation of individuals from ‘consumers’ to ‘users’ in some form of a closed system. The emphasis throughout the discussion remains that of viewing solid waste as part of a larger effort of comprehensive natural resources management. The last is examined in the context of a cultural system that recognizes not only interdependencies but also a pervasive life style and shared attitudes which relate social goals, technological capabilities, and environmental conservation.
Possible correlation between increased vigour and chitinase activity expression in tobacco

Nicotiana tabacum (tobacco) plants with several-fold increased chitinase enzyme activity levels were obtained through transformation with a Zea mays (maize) chitinase cDNA clone, Ch2, under the control of the CaMV 35S promoter. There was a linear correlation (r=0.74, P=0.009) between the endochitinase activity and the weight of homozygous seedlings grown in the greenhouse in some experiments. Progeny seedlings of self-pollinated regenerants (heterozygous for Ch2) grown for 18 d in Petri plates could be separated into vigorous and non-vigorous categories based on size, which were predicted to be 2n or 1n and null, respectively, for Ch2. Testing showed that the visually estimated vigour of these progeny co-segregating for Ch2 and nptII generally correlated with resistance to kanamycin and chitinase activity. There was also a correlation between growth and chitinase activity in suspension cultures derived from transgenic and wild-type when measured after 20 d. Twelve-day-old wild-type and transformed seedlings grown in soil under culture room conditions in closed plastic containers were visibly taller and had higher seedling weights than their counterparts grown under mist in the greenhouse. Likewise, the chitinase activity in the cell wall-bound proteins of the faster growing seedlings was more than double that of the greenhouse-grown seedlings. While these studies do not always demonstrate the correlation between vigour and chitinase activity, overall, they do support the hypothesis that chitinases have a role in plant growth.
A structured macro assembler for the Event Handler

A description is given of a portable macro cross-assembler that has been developed for the Event Handler using UNIX compiler construction tools. The assembler is implemented as separate code generation and preprocessor programs. Besides the basic Event Handler instructions, the code generator supports structured conditionals, structured loops, and high-level-language-like constant calculations. The preprocessor allows for symbolic text constants, symbolic numeric constants with computed values, messages, include files, macros, and conditional assembly. These features can either enhance the direct programming of the Event Handler or define minilanguages that hide programming details from the user. The assembler is not dependent on a particular data acquisition system and thus may be of interest to other Event Handler users. >
A Comprehensive Protocol for Manual Segmentation of the Medial Temporal Lobe Structures

The present paper describes a comprehensive protocol for manual tracing of the set of brain regions comprising the medial temporal lobe (MTL): amygdala, hippocampus, and the associated parahippocampal regions (perirhinal, entorhinal, and parahippocampal proper). Unlike most other tracing protocols available, typically focusing on certain MTL areas (e.g., amygdala and/or hippocampus), the integrative perspective adopted by the present tracing guidelines allows for clear localization of all MTL subregions. By integrating information from a variety of sources, including extant tracing protocols separately targeting various MTL structures, histological reports, and brain atlases, and with the complement of illustrative visual materials, the present protocol provides an accurate, intuitive, and convenient guide for understanding the MTL anatomy. The need for such tracing guidelines is also emphasized by illustrating possible differences between automatic and manual segmentation protocols. This knowledge can be applied toward research involving not only structural MRI investigations but also structural-functional colocalization and fMRI signal extraction from anatomically defined ROIs, in healthy and clinical groups alike.
A technique for estimating total spine numbers on golgi‐impregnated dendrites

The functional significance of dendritic spines and their morphological sensitivity to a wide spectrum of experimental manipulations and pathological states have led to a number of studies in which counts of dendritic spine number have been carried out. These studies have, for the most part, involved the enumeration of only those spines which protrude from the opaque shafts of Golgi-impregnated dendrites into the clear zones flanking the dendrite. Such counts, limited to only those spines which are visible, underrepresent the true total number of spines borne by the dendrites. The magnitude of underrepresentation correlates positively with dendritic shaft diameter and negatively with spine length. This seriously restricts the usefulness of comparisons of spine density between dendrites, or even between segments of the same dendrite. In the present report, a geometrically based method is presented whereby total dendritic spine numbers can be estimated with reasonable accuracy, taking into account factors such as dendrite diameter and spine length. The technique entails the following principal steps: a determination, for a given length of dendrite over which spines are to be enumerated, of the volume of the flanking zones in which spines are visible and can be counted; a determination of the volume of the entire zone which encircles the dendritic shaft and which contains all spines, both visible and not visible; and a proportional extrapolation from the number of visible spines to obtain an estimate of the true total spine number. Tests of the predictive accuracy of the technique using dendrites of known total spine number suggest that estimates which deviate from true total spine numbers by less than 10% can be achieved.
An Analysis of the Effectiveness of Telephone Intervention in Reducing Absences and Improving Grades of College Freshmen

A telephone intervention to reduce student absences was implemented during the 2000–2001 academic year in freshmen English classes at a southern university. A total of 345 students were included in 2 experimental studies. Students in the intervention group who obtained more absences than allotted by class professors received telephone intervention, whereas students with excessive absences in the control group did not receive telephone intervention. Results revealed that students in the intervention groups had significantly fewer absences and higher grades (p < .01) than students in the control groups during both semesters of the study. Also, more students in the intervention group were retained from the Spring 2001 semester to the Fall 2001 semester as compared to students in the control groups.
Can a Successful ESL Teacher Hold Deficit Beliefs of Her Students’ Home Languages and Cultures?

In this article the author explores the seeming contradictions between the successful teaching practices of an English as a Second Language teacher and the deficit beliefs she expressed toward her students’ home languages and cultures. This teacher believed her students were smart and capable, and she held herself accountable for her students achieving academic success.
A python graphics package for the first day and beyond

We demonstrate the use of a new Python graphics package named cs1graphics, while discussing its impact on pedagogy and showcasing the recent work of our students. Our package was originally developed with two goals in mind. First, we insisted that it be intuitive enough that students can sit down and make use of it from the very first day of an introductory class. Second, we wanted to provide seamless support for intermediate and advanced lessons as students progress. The resulting package is freely available at www.cs1graphics.org. We find its combination of simplicity and functionality unmatched by existing packages.
The Complex Cooling Core of A2029: Radio and X-Ray Interactions

We present an analysis of Chandra observations of the central regions of the cooling flow cluster A2029. We find a number of X-ray filaments in the central 40 kpc, some of which appear to be associated with the currently active central radio galaxy. The outer southern lobe of the steep-spectrum radio source appears to be surrounded by a region of cool gas and is at least partially surrounded by a bright X-ray rim similar to that seen around radio sources in the cores of other cooling flow clusters. Spectroscopic fits show that the overall cluster emission is best fitted by either a two-temperature gas (kThigh = 7.47 keV and kTlow = 0.11 keV) or a cooling flow model with gas cooling over the same temperature range. This large range of temperatures (over a factor of 50) is relatively unique to A2029 and may suggest that this system is a very young cooling flow in which the gas has only recently started cooling to low temperatures. The cooling flow model gives a mass deposition rate of = 56 M☉ yr-1. In general, the cluster emission is elongated along a position angle of 22° with an ellipticity of 0.26. The distribution of the X-ray emission in the central region of the cluster is asymmetric, however, with excess emission to the northeast and southeast compared with that to the southwest and northwest, respectively. Fitting and subtracting a smooth elliptical model from the X-ray data reveals a dipolar spiral excess extending in a clockwise direction from the cluster core to radii of ~150 kpc. We estimate a total mass of Mspr ~ 6 × 1012 M☉ in the spiral excess. The most likely origin of the excess is either stripping of gas from a galaxy group or from bare dark matter potential that has fallen into the cluster or sloshing motions in the cluster core induced by a past merger.
Resists and processes for 1 kV electron beam microcolumn lithography

Low‐voltage electron beamlithography has been considered for some time for high‐resolution lithography because of reduced proximity effects, increased resist sensitivities, and reduced substrate damage. An accelerating voltage of 1 kV is being considered for the operation of microcolumns that are being developed for use in an innovative, high‐speed, high‐resolution electron beamlithography system. The development of resists and processes for use at 1 kV then becomes one of the essential components in this developing technology. Since 1 keV electrons have a penetration depth of ∼60 nm in organic polymers, the resists used for electron beam exposures must be correspondingly thin. This makes the development of processes for pattern transfer a challenge. Here, we report on three resist and processing schemes for use at 1 kV which can be used to produce 50–100 nm wide structures. Structures as small as 50 nm wide with 3 to 1 aspect ratios, and trenches 300 nm deep and less than 100 nm wide have been successfully transferred into Si substrates. Despite the use of very thin resists, the transferred patterns do not suffer from noticeable defects.
( i,j ) competition graphs

Abstract If D is an acyclic digraph, its competition graph has the same vertex set as D and an edge between vertices x and y if and only if for some vertex u, there are arcs (x, u) and (y, u) in D. We study competition graphs of acyclic digraphs D when the indegrees and outdegrees of the vertices of D are restricted. Under degree restrictions, we characterize the competition graphs and are able to solve the important open problem of characterizing acyclic digraphs whose competition graphs are interval graphs. We also characterize the competition graphs which are interval graphs.
A Multimethod Examination of the Benefits and Detriments of Intragroup Conflict

I would like to thank Jennifer A. Chatman, Margaret Neale, Elizabeth Weldon, Dawn lacobucci, and Oswald Werner for comments on earlier drafts. I would also like to thank Linda Pike for her tremendous help, as well as Robert I. Sutton and three anonymous reviewers. This study examines the structure of 105 work groups and management teams to address the question of whether conflict can be beneficial. Multiple methods were used to examine the effects of conflict on both individualand group-level variables to provide a more refined model of intragroup conflict. Results show that whether conflict was beneficial depended on the type of conflict and the structure of the group in terms of task type, task interdependence, and group norms. Relationship and task conflicts were negatively associated with individuals' satisfaction, liking of other group members, and intent to remain in the group. In groups performing very routine tasks, disagreements about the task were detrimental to group functioning. In contrast, in groups performing nonroutine tasks, disagreements about the tasks did not have a detrimental effect, and in some cases, such disagreements were actually beneficial. Contrary to expectations, norms encouraging open discussion of conflict were not always advantageous. The results suggest that while such norms were associated with an increase in the number and intensity of relationship conflicts, they did not increase members' ability to deal with the conflicts constructively. The model developed here contributes to an integrated perspective on organizational conflict.'
Towards the development of a humanoid arm by minimizing interaction forces through minimum impedance control

We present the results from our work in the development of a robotic arm with minimal impedance. The development of such an arm is useful for gentle exploration of unknown objects in unstructured environments. Similar to a human, the robotic arm should minimize the contact forces in the event of unanticipated contact with unknown objects in the absence of visual feedback. To accomplish this, our strategy is to develop a good model of the robotic system so that we can use low gains which in turn will lead to low impedance and hence low contact forces in manipulation tasks in unstructured environments. The paper demonstrates how good modeling and feedforward compensation can result in low interaction forces without any external force sensing. We present experimental results to demonstrate the validity of our model and approach.
Lay Appraisal of Cognitive Impairment Symptoms and Related Prevention Beliefs in a Community-Dwelling Sample of Midlife and Older Adults:

This study explores how age and health-related quality of life (HRQoL) may be related to the identification and appraisal of cognitive impairment symptoms as well as associated prevention beliefs. Participants were 140 community-dwelling adults ranging in age from 49 to 90 years who completed a survey containing a vignette about an adult with cognitive impairment symptoms and questions about the illness symptoms, prevention beliefs, and HRQoL. Identification of symptoms as Alzheimer's disease or dementia was reported by 83% of respondents. Correlational analyses suggested age and education to be associated with perceived significance of symptoms as well as the recommendation to seek medical care. Multiple regression modeling indicated interactive effects that suggest advancing age and poor HRQoL may be associated with greater delay in seeking care for cognitive impairment symptoms and unrealistic optimism regarding prevention outcomes. Educational interventions to bolster the individuals' and caregivers' ...
Nonequilibrium Boundary-Layer Effects on the Aerodynamic Heating of Hypersonic Waverider Vehicles

The aerodynamic heating of hypersonic waverider vehicle configurations is examined in the high-altitude hypersonic flight regime where nonequilibrium dissociation-recombination in the boundary-layer and finite surface catalysis effects are both important. Analytical treatment of these effects is given for highly cooled surfaces in three important heating regions: 1) the nose, 2) the swept-wing leading-edge attachment line, and 3) the windward body center line. Relationships for the relative nonequilibrium effects are developed for each region that enable both computer code-prediction validation and cost-effective parametric engineering studies.