cssi/SciSciGPT-SciSciNet huggingface dataset:
On maximum logical candor and extensionality

The phrase is Ryle's, but it goes without saying, does it not, that in our serious philosophical work, nothing less than "maximum logical candor" should suffice.x Of course no one wishes to be burdened with excessive and wearisome details which obfuscate rather than clarify. No one wishes to be a mere "purveyor of unprofitable subtleties".2 No one wishes, in Peirce's phrase, to be "captious about trifles and neglectful of weightier matters, condemning every inference really valuable and admitting only such as are really childish." 3 On the other hand, philosophers should surely be prepared to furnish any details which might be needed in some specific context to settle a logical point at issue, or to bring to a focus logical relationships somewhat obscure. For such purposes, a maximum logical analysis with commensurate candor is often indis pensable. The rules of logic are many and manifold. There is little agreement as to what, precisely, they are. From among the multiplicity of logics, there is no one which can be pointed out as providing the rules of logic. The various alternative logics clamor for attention, and their proponents are eloquent as to the special virtues of each. Unfortunately these virtues usually turn out to be purely mathematical. For this logic the Ent scheidungsproblem is solvable; that has such and such a completeness property; this other contains 256 different numbers all very closely akin to the natural number two. Important philosophical issues are at stake here, however, in the appraisal of the multiplicity of logics. Not all of them are philosophically above suspicion, and a strong argument can be made that the classical, two-valued logic of truth-functions, quantifiers, and perhaps identity (with logical syntax and semantics constructed on its basis), has a privileged status.4 The very meaning of'maximum logical candor' is to be found, then, it would seem, on the basis of this kind of logic and semantics.
Theoretical Analysis of Oxygen Adsorption on Pt-Based Clusters Alloyed with Co, Ni, or Cr Embedded in a Pt Matrix

A systematic evaluation of the oxygen molecule dissociation on metal and metal alloy surfaces is performed to determine optimal catalytic materials for oxygen dissociation. The study focuses on the physical, chemical, and electrical characteristics at the oxygen−metal interface where the effects of the oxygen molecule and the metal atoms in its neighborhood, as well as the effects of the extended and continuum nature of the catalyst, are considered through the use of molecular and extended ab initio procedures interconnected by a Green function formalism to account for the interfacial characteristics.
Columbia River volcanism - The question of mantle heterogeneity or crustal contamination

It is found that, although crystal fractionation played an important role in producing the chemical characteristics of Columbia River Province basalts displaying a wide range of chemical and isotopic compositions, the isotopic variability calls for the involvement of at least two isotopically distinct components. The major and trace element characteristics of the main volume of the basalts are not consistent with a metasomatized mantle source region, and the presence of a primordial mantel component is not supported by the chemical data. Models of simple binary mixing between a primary magma and Precambrian sialic crustal materials, while satisfying the observed Nd and Sr isotopic variations, fail to account for major trace element abundances. The combination of crustal assimilation and fractional crystalization is found to give a superior fit to the compositional data.
Decomposition-based design optimisation of electric vehicle powertrains using proper orthogonal decomposition

Effective powertrain design for the emerging electric vehicle market is a complex, multidisciplinary problem. As such, engineers may often use formal decomposition-based optimisation strategies to partition the problem into more manageable subproblems and then integrate their solutions to obtain an optimal system design. Sometimes, these strategies yield decision variables that consist of highly-discretised functional data which must be reduced to enable efficient, practical optimisation. Reduced representation methods such as Proper Orthogonal Decomposition (POD) can help achieve this goal, but the effectiveness of POD in terms of design solution accuracy and optimisation efficiency is dependent on its interaction with the optimisation strategy. Therefore, this paper investigates the impact of a tuning parameter within POD on solution accuracy and optimisation efficiency in the context of decomposition-based electric vehicle powertrain design.
Personality and Political Participation: Does Self-Ideal Discrepancy Make a Difference?:

Summary.-Rival accounts of the relation between personalicy adjustment, e.g., psychic fulfillment, self-actualizarion, and the like, and political participation are summarized, and the notion of self-ideal congruence introduced as an independent variable of relevance. The latter, as an aspect of self-actualization, was then investigated for its relationship to political participarion. Findings from a sample of 85 college students did not conform to expectations derived from "actualization" theory bur were not inconsistent with "compensation" perspectives, as no positive relationship was found between congruence and two measures of political participation. Recent research on the personality correlates of political participation has begun to crystallize into rwo schools of thought on the question of the relationship between political activism, on the one hand, and various dimensions or global assessments of psychological adjustment or positive mental health, on the other (Knutson, 1973). One school-which can be called the "actualization" camp--starts with the premise that higher rates of political participation call for greater investments of mental as well as physical energy on the part of participants. From this it is argued that individuals experiencing excessive anxieties borne of psychological conflict and persons who are preoccupied with unmet psychological needs will be less inclined, by virtue of the energy-deflating nature of these conflicts, anxieties and preoccupations, to participate with vigor . in political activities than will be other persons who are generally "more at home with themselves" psychologically.
Vectorgraph coding: efficient coding of line drawings

Abstract A method for the efficient coding of line drawings is discussed. The intent is to provide an extremely low bandwidth representation for images, preserving “intelligible” image content but not necessarily image quality. This has led to an image transformation involving edge enhancement, detection, line thinning, and polygonal splining which is termed the polygonal transformation . The graph-like image which results from this transformatiom is coded quite efficiently by using vectorgraph coding , which codes a series of vectors in a manner similar to that used in many computer graphics systems. This technique has been applied to a body of images of American Sign Language and the results are encouraging.
High precision valence bond potential curve for the Cl2 molecule

Abstract For the Cl2 molecule, complete configuration interaction calculations have been carried at six internuclear separations in terms of accurate Hartree-Fock atomic orbitals (HFAO's). The calculations were greatly simplified by computing all integrrals directly over the HFAO's. The calculated dissociation energy was 0.71 eV, compared to the molecular SCF value 0.87 eV, and the experimental value 2.48 eV.
5 Hz, >250 mJ optical parametric chirped-pulse amplifier at 1053 nm

A 250?mJ, 5?Hz repetition rate optical parametric chirped-pulse amplifier with near-Fourier-transform-limited, 430?fs pulses and a beam that can be focused to near the diffraction limit is demonstrated. A pump laser with engineered spatial and temporal profiles allows an overall pump-to-signal conversion efficiency of 34% to be achieved.
Energy storage techniques for hydraulic wind power systems

Hydraulic wind power transfer systems allow collecting of energy from multiple wind turbines into one generation unit. They bring the advantage of eliminating the gearbox as a heavy and costly component. The hydraulically connected wind turbines provide variety of energy storing capabilities to mitigate the intermittent nature of wind power. This paper presents an approach to make wind power become a more reliable source on both energy and capacity by using energy storage devices, and investigates methods for wind energy electrical energy storage. The survey elaborates on three different methods named “Battery-based Energy Storage”, Pumped Storage Method, and “Compressed Air Energy Storage (CAES)”.
Variance-Covariance Components Associated with Trimester Yields of Milk and Fat and Multiple Trait Sire Evaluation for Trimester Yields

Genotypic and phenotypic variances and covariances for milk and fat yields of three equally-spaced intervals in first lactation, days 1 to 90, 91 to 180, and 181 to 270, were estimated from 26,523 records of initial progeny-test daughters of 2,086 Holstein sires. Henderson's method 3 was used with a model that included fixed herd-years, fixed age-month of freshening, and random sire and residual effects. Heritabilities for milk yields were .21, .21, and .13 for the first, second, and third 90 days in lactation and for fat yields were .19, .16, and .10. Heritabilities for milk and fat yields over the entire 270 days postpartum were .22 and .22. Genetic correlations among partial yields were high and ranged from .74 to .99 for milk and .86 to .99 for fat. Genotypic and phenotypic variances were used to predict breeding values for trimester milk yield by multiple trait, mixed model procedures for 3,797 Holstein artificial insemination sires from 283,900 first-lactation milk records of their daughters during the first 90, second 90, and third 90 days in lactation. Correlations among proofs for the three trimesters ranged from .85 to .94. Correlation between the sum of three trimester multiple trait proofs and proof for milk yield for 270 days of lactation from single trait analysis was .99. Correlations among proofs indicate sires may rank differently for milk yield in the three periods.
Favoring heterotrimeric boroxine formation using an internal Lewis base: a computational study.

Heterotrimeric arylboroxines can be favorably formed by designing one of the arylboronic acid monomers to contain a pendant Lewis base. Using density functional theory (B3LYP//6-311+G*) calculations including Poisson−Boltzmann implicit solvent, we found that AB2 trimeric arylboroxines were thermodynamically favored over A2B, A3, or B3, where A and B are monomeric arylboronic acids with and without a pendant Lewis base, respectively. The most stable AB2 trimers were formed when the B monomer contained electron-withdrawing substituents, particularly halogens in the para-position or π-acceptors in the meta-position. On the other hand, adding different para-substituents to the A monomer did not significantly change the energetics. Our calculations also suggest that ABC trimers with three different monomers will not be significantly favored over AB2 trimers when making small electronic perturbations, by changing the substituents on each monomer.
Unanticipated Postoperative Ventricular Tachyarrhythmias

Eighteen (1.4%) of 1,251 patients who underwent cardiac operations during a three-year period had new sustained ventricular tachycardia (12 patients) or ventricular fibrillation (6 patients) not caused by but resulting in hemodynamic compromise. In 13 patients, the initial arrhythmia occurred in the first 48 hours postoperatively. Lidocaine was being administered to 10 of these patients for suppression of previously noted ventricular ectopy, but it did not prevent the occurrence of the arrhythmia. The initial episode was fatal for 5 patients. Two of these deaths were directly related to the adverse effects of the antiarrhythmic agents used to suppress ventricular tachycardia or fibrillation. Five of 10 survivors underwent electrophysiological studies after initial resuscitation. In all 5, programmed ventricular stimulation reproduced the clinical arrhythmia. There have been 2 late sudden deaths in patients who either did not undergo or remained uncontrolled at electrophysiological study during serial drug trials. Our experience suggests that a cardiac operation may unmask or induce potentially lethal arrhythmias that previously had not been apparent. Pharmacological suppression of ventricular ectopy does not necessarily prevent ventricular tachycardia or ventricular fibrillation in the early postoperative period. Electrophysiological study may be helpful in determining the appropriate prophylactic therapy in such patients.
Speech and pause characteristics in multiple sclerosis: a preliminary study of speakers with high and low neuropsychological test performance.

This preliminary study investigated how cognitive-linguistic status in multiple sclerosis (MS) is reflected in two speech tasks (i.e. oral reading, narrative) that differ in cognitive-linguistic demand. Twenty individuals with MS were selected to comprise High and Low performance groups based on clinical tests of executive function and information processing speed and efficiency. Ten healthy controls were included for comparison. Speech samples were audio-recorded and measures of global speech timing were obtained. Results indicated predicted differences in global speech timing (i.e. speech rate and pause characteristics) for speech tasks differing in cognitive-linguistic demand, but the magnitude of these task-related differences was similar for all speaker groups. Findings suggest that assumptions concerning the cognitive-linguistic demands of reading aloud as compared to spontaneous speech may need to be re-considered for individuals with cognitive impairment. Qualitative trends suggest that additional...
Total Dust, Respirable Dust, and Microflora Toxin Concentrations in Colorado Corn Storage Facilities

To aid in the process of characterizing corn dust exposures on farms and in elevators in northeastern Colorado, several parameters were examined. Total dust and respirable dust samples were collected and evaluated. Potentially dangerous dust components evaluated were respirable silica, endotoxin, and mycotoxin levels. Many of the total dust samples (58%) would have exceeded 8-hour time-weighted average (TWA) had sampling been conducted for 8 hours; on farms the operation takes between two and four hours. The same statement may be made for respirable dust samples collected for this project. Nearly 33 percent of the respirable dust samples collected would have exceeded the Occupational Safety and Health Administration (OSHA) TWA had sampling been conducted over an 8-hour period. Respirable silica standards were exceeded at 25 percent of the sampling locations. Presence of mycotoxins at all sites was confirmed by the use of ELISA kits. The most significant finding of this study was high levels of endotoxin a...
Post hoc decision to use a covariate

Abstract A computer simulation of ten thousand experiments showed that some methods of deciding between analysis of variance and analysis of covariance may distort the significance level. These results show that it is more desirable either to always use a logical covariate or to make this decision based on the significance of the slope of the covariate but not by testing for chance skewing of the covariate.
The South Channel Ocean Productivity EXperiment

Abstract The South Channel Ocean Productivity EXperiment (SCOPEX) was a multidisciplinary study of a whale-zooplankton predator-prey system in the southwestern Gulf of Maine, focusing on the oceanographic factors responsible for the development of dense patches of the copepod Calanus finmarchicus , which comprise the major prey resource for right whales ( Eubalaena glacialis ). Three non-mutually exclusive hypotheses underlay the study: patch development is due to (1) extremely high in situ primary and secondary productivity; (2) large numbers of Calanus advected into the region and concentrated by hydrographic processes; and/or (3) a behavioral tendency of the copepods themselves to aggregate. The results confirmed the cooccurrence of right whales with high density Calanus patches, and also demonstrated that right whales fed on patches with higher proportions of larger lifestages. The physical oceanographic studies supported the advection hypothesis, possibly augmented by a tendency of Calanus to aggregate, but there was little evidence to support the productivity hypothesis.
Isocrates and Plato on rhetoric and rhetorical education

(1991). Isocrates and Plato on rhetoric and rhetorical education. Rhetoric Society Quarterly: Vol. 21, No. 1, pp. 60-71.
Rewriting Citizenship? Civic Education in Costa Rica and Argentina.

To what degree are nations ‘rewriting’ citizenship by expanding discussions of human rights, diversity and cultural pluralism in modern civic education, and what explains variation between countries? This study addresses these issues by analysing the intended content of civic education in Costa Rica and Argentina. Over time, civic education in both countries has become more focused on rights and the empowerment of individuals. In addition, both countries embrace aspects of global citizenship through an affirmation of human rights. Citizenship thus expands outward and upward, incorporating more groups and people into the national polity while also broadening the concept of citizenship beyond the nation‐state. Nevertheless, Costa Rica and Argentina vary in the intensity of the adoption of global citizenship, most likely a result of divergent historical experiences with state sponsored violence.
Transduction of the chemotactic signal to the actin cytoskeleton of Dictyostelium discoideum

Abstract Dictyostelium discoideum amebae chemotax toward folate during vegetative growth and toward extracellular cAMP during the aggregation phase that follows starvation. Stimulation of starving amebae with extracellular cAMP leads to both actin polymerization and pseudopod extension (Hall et al., 1988, J. Cell. Biochem.37, 285–299). We have identified an actin nucleation activity (NA) from starving amebae that is regulated by cAMP receptors and controls actin polymerization (Hall et al., 1989, J. Cell Biol., in press). We show here that NA from vegetative cells is also regulated by chemotactic receptors for folate. Our studies indicate that NA is an essential effector in control of the actin cytoskeleton by chemotactic receptors. Guided by a recently proposed model for signal transduction from the cAMP receptor (Snaar-Jagalska et al., 1988, Dev. Genet.9, 215–225), we investigated which of three signaling pathways activates the NA effector. Treatment of whole cells with a commercial pertussis toxin preparation (PT) inhibited cAMP-stimulated NA. However, endotoxin contamination of the PT appears to account for this effect. The synag7 mutation and caffeine treatment do not inhibit activation of NA by cAMP. Thus, neither activation of adenylate cyclase nor a G protein sensitive to PT treatment of whole cells is necessary for the NA response. Actin nucleation activity stimulated with folate is normal in vegetative fgdA cells. However, cAMP suppresses rather than activates NA in starving fgdA cells. This indicates that the components of the actin nucleation effector are present and that a pathway regulating the inhibitor(s) of nucleation remains functional in starving fgdA cells. The locus of the fgdA defect, a G protein implicated in phospholipase C activation, is directly or indirectly responsible for transduction of the stimulatory chemotactic signal from cAMP receptors to the nucleation effector in Dictyostelium.
Decrease hepatic cytosolic glucocorticoid receptor binding upon treatment of rodents (mice and rats) with 2,3,7,8-tetrachlorodibenzo-dioxin

Abstract 2,3,7,8-Tetrachlorodibenzo- p -dioxin (TCDD) treatment of mice and rats significantly reduced hepatic cytosolic glucocorticoid (GRc) binding as measured by Scatchard analysis. Studies of the rat GRc using Western blot analysis demonstrated that the reduction of steroid binding following TCDD treatment was not accompanied by a corresponding decrease in immunodetectable receptor protein. This data suggests that TCDD may influence glucocorticoid binding by modifying post-translational events that regulate the steroid-binding capacity of the glucocorticoid receptor.
CC1-01: A Simulated Diabetes Learning Intervention Improves Provider Knowledge and Confidence in Managing Diabetes

Background/Aims Provider performance on diabetes measures is variable, and is at least partially due to differences in provider knowledge and confidence in managing patients with diabetes and multiple co-morbidities.
Fractionation of hydrogen and deuterium on Venus due to collisional ejection.

The fractionation factor ∫ is important for interpreting the current escape fluxes of H and D on Venus and how the D/H ratio has evolved. The escape flux is currently governed by the two processes of charge exchange and collisional ejection by fast oxygen atoms. Using a best-fit parameterized equation for the O-H scattering angle phase function, more accurate branching ratios for the oxygen ion dissociation and including the effects of the initial energy and momentum of the ions and electrons, as well as for the hydrogen and deuterium gas, we have reanalyzed the collisional ejection process. Our analysis produces improved values for the efficiency of H and D escape as a function of the ionospheric temperature. From our results we propose the reduction of the hydrogen flux for collisional ejection from 8 to 3.5 × 10^6 cm^(−2) s^(−1). Assuming that collisions leading to escape occur mostly in the region between 200 and 400 km, the revised D/H fractionation factor due to collisional ejection is 0.47, where previously the process had been considered completely discriminating against deuterium escape (or ∫ ∼ 0). The resulting deuterium flux is 3.1 × 10^4 cm^(−2) s^(−1), roughly 6 times the flux due to charge exchange, making collisional ejection the dominant escape mechanism for deuterium on Venus.
Suppression of long-range couplings in heteronuclear two-dimensional J spectroscopy. Effects of nonuniform one-bond couplings

Abstract If long-range J couplings between 13 C and distant 1 H spins are suppressed by the selective reversal of directly attached protons, heteronuclear 2-D NMR can be used for quick determinations of CH m multiplicity and one-bond coupling constants C 1 J CH ). Theoretical and experimental analysis show that nonuniform values of 1 J CH may give rise to spurious peaks, but the reliability of the results is not affected.
Dnmt3a is essential for hematopoietic stem cell differentiation.

Margaret Goodell, Wei Li and colleagues report conditional ablation of the Dnmt3a DNA methyltransferase in hematopoietic stem cells (HSCs) in mice. They show that Dnmt3a is critical for epigenetic silencing of HSC regulatory genes and for HSC differentiation.
History and Evolution of the Offshore Oil and Gas Industry in Southern Louisiana: Worker Perspectives

The history of the offshore oil and gas industry in the Gulf of Mexico is one of both progressive and punctuated development. New technologies, forms of work organization, and regulatory regimes have all combined over the past seventy years to influence the evolution of this industry. This paper reports early results of a multiyear, multi-team effort to document this history and its impacts on southern Louisiana. It focuses on the work of one team, applied anthropologists from the University of Arizona, to capture the history from the perspectives of the workers and local entrepreneurs who made this industry happen.Copyright © 2002 by ASME
Crystallization studies of lunar igneous rocks: crystal structure of synthetic armalcolite.

Crystals of armalcolite, Mg0.5Fe0.5Ti2O5, up to several millimeters in length have been grown from a glass initially having the composition of lunar rock 10017. A single-crystal x-ray study has confirmed that the crystals are isomorphous with pseudobrookite and has shown that the cations are strongly ordered, with the Ti4+ ions occupying the 8f sites and the Fe2+ and Mg2+ ions randomly distributed over the 4c sites. An examination of karrooite, MgTi2O5, has revealed a similar distribution of Mg2+ and Ti4+ ions. A reexamination of earlier x-ray and Mossbauer data for pseudobrookite, Fe2TiO5, has shown that it is more consistent with this type of ordering than with the inverse structure that has been generally assumed.
The effect of SDS on protein zone dispersion in polyacrylamide gel electrophoresis

Abstract The zone dispersions of the reduced subunit of β-lactoglobulin B and its derivative with sodium dodecyl sulfate (SDS) were measured during polyacrylamide gel electrophoresis (PAGE) using the apparatus for continuous optical scanning at 280 nm. The ratio of apparent diffusion coefficients (D′) of the reduced subunit of β-lactoglobulin B (1.71 × 10−6 cm2/s) and of its SDS-derivative (7.1 × 10−7 cm2/s) was found to be 2.4 under the conditions of PAGE (pH 10.4, 0.015 ionic strength, 1°C, 4 mA/cm2 current density, 50 μg protein load, 10% T gel) used. This is nearly twice the value of 1.3 predicted, under the assumption of sphericity for these protein molecules, on the basis of the binding of 1.4 g of SDS per gram of protein. It is postulated that the increment in zone sharpness (decrease in apparent diffusion coefficient) over that predicted by SDS binding alone is a general property of SDS-proteins providing gel electrophoresis in SDS-containing buffers with a resolving power larger than that obtained in the absence of the detergent.
Design of 2,5-dimethyl-3-(6-dimethyl-4-methylpyridin-3-yl)-7-dipropylaminopyrazolo[1,5-a]pyrimidine (NBI 30775/R121919) and structure--activity relationships of a series of potent and orally active corticotropin-releasing factor receptor antagonists.

We have previously shown that 3-phenylpyrazolo[1,5-a]pyrimidines exemplified by 8 were potent antagonists of the human corticotropin-releasing factor-1 receptor. A series of 3-pyridylpyrazolo[1,5-a]pyrimidines 15, 25−30, 34, and 35 containing a weakly basic pyridine ring at the 3-position of the bicyclic nucleus was designed to reduce lipophilicity from the initial leads such as 7. Here, we showed that these 3-pyridyl compounds exhibited potent antagonists at the human CRF1 receptor. Moreover, the hydrophilic and weakly basic pyridine moiety increased the water solubility of some analogues. Compound 26h exhibited good binding affinity at the human CRF1 receptor with a Ki value of 3.5 nM. As a functional antagonist, it dose-dependently inhibited CRF-stimulated cAMP production in cells expressing the CRF1 receptor (IC50 = 50 nM), and CRF-stimulated ACTH release from cultured rat pituitary cells (IC50 = 20 nM). 26h had a log P value of 4.9 and water solubility of greater than 10 mg/mL. Pharmacokinetic studie...
Head Pose Estimation From a 2D Face Image Using 3D Face Morphing With Depth Parameters

This paper presents estimation of head pose angles from a single 2D face image using a 3D face model morphed from a reference face model. A reference model refers to a 3D face of a person of the same ethnicity and gender as the query subject. The proposed scheme minimizes the disparity between the two sets of prominent facial features on the query face image and the corresponding points on the 3D face model to estimate the head pose angles. The 3D face model used is morphed from a reference model to be more specific to the query face in terms of the depth error at the feature points. The morphing process produces a 3D face model more specific to the query image when multiple 2D face images of the query subject are available for training. The proposed morphing process is computationally efficient since the depth of a 3D face model is adjusted by a scalar depth parameter at feature points. Optimal depth parameters are found by minimizing the disparity between the 2D features of the query face image and the corresponding features on the morphed 3D model projected onto 2D space. The proposed head pose estimation technique was evaluated on two benchmarking databases: 1) the USF Human-ID database for depth estimation and 2) the Pointing'04 database for head pose estimation. Experiment results demonstrate that head pose estimation errors in nodding and shaking angles are as low as 7.93° and 4.65° on average for a single 2D input face image.
Roles of dynamic and reversible histone acetylation in plant development and polyploidy

Transcriptional regulation in eukaryotes is not simply determined by the DNA sequence, but rather mediated through dynamic chromatin modifications and remodeling. Recent studies have shown that reversible and rapid changes in histone acetylation play an essential role in chromatin modification, induce genome-wide and specific changes in gene expression, and affect a variety of biological processes in response to internal and external signals, such as cell differentiation, growth, development, light, temperature, and abiotic and biotic stresses. Moreover, histone acetylation and deacetylation are associated with RNA interference and other chromatin modifications including DNA and histone methylation. The reversible changes in histone acetylation also contribute to cell cycle regulation and epigenetic silencing of rDNA and redundant genes in response to interspecific hybridization and polyploidy.
Epidermal growth factor-induced hydrolysis of phosphatidylcholine by phospholipase D and phospholipase C in human dermal fibroblasts.

The enzymatic pathways for formation of 1,2-diradylglyceride in response to epidermal growth factor in human dermal fibroblasts have been investigated. 1,2-Diradylglyceride mass was elevated 2-fold within one minute of addition of EGF. Maximal accumulation (4-fold) occurred at 5 minutes. Since both diacyl and ether-linked diglyceride species occur naturally and may accumulate following agonist activation, we developed a novel method to determine separately the alterations in diacyl and ether-linked diglycerides following stimulation of fibroblasts with EGF. Utilizing this method, it was found that approximately 80% of the total cellular 1,2-diradylglyceride was diacyl, the remaining 20% being ether-linked. Addition of EGF caused accumulation of 1,2-diacylglyceride with out alteration in the level of ether-linked diglyceride. Thus, the observed induction of 1,2-diradylglyceride by EGF was due exclusively to increased formation of 1,2-diacylglyceride. In cells labelled with [3H]choline, the water soluble phosphatidylcholine hydrolysis products, phosphorylcholine and choline, were increased 2-fold within 5 minutes of addition of EGF. No hydrolysis of phosphatidylethanolamine, phosphatidylserine, or phosphatidylinositol was observed. Quantitation by radiolabel and mass revealed equivalent elevations in phosphorylcholine and choline, suggesting stimulation of both phospholipase C and phospholipase D activities. To identify the presence of EGF-induced phospholipase D activity, cells were labelled with exogenous [3H]1-0-hexadecyl, 2-acyl phosphatidylcholine and its conversion to phosphatidic acid in response to EGF determined. Radiolabelled phosphatidic acid was detectable in 15 seconds after addition of EGF and was maximal (3-fold) at 30 seconds. Consistent with the presence of EGF-induced phospholipase D activity, treatment of cells with EGF, in the presence of [14C]ethanol, resulted in the rapid formation of [14C]phosphatidylethanol, the product of phospholipase D-catalyzed transphosphatidylation. The formation of phosphatidylethanol, which competes for the formation of phosphatidic acid by phospholipase D, did not diminish the induction of 1,2-diglyceride by EGF. These data suggest that the phosphatidic acid formed by phospholipase D-catalyzed hydrolysis of phosphatidylcholine is not a major precursor of the observed increased 1,2-diglyceride. Thus, the induction of 1,2-diacylglycerol by EGF may occur primarily via phospholipase C-catalyzed hydrolysis of phosphatidylcholine.
Autocorrelation Function and Power Spectrum of Two-State Random Processes Used in Neurite Guidance

During development neurons extend and retract cytoskeletal structures, chiefly microtubules and filopodia, to process informational cues from the extracellular environment and thereby guide growth cone migration toward an appropriate synaptic partner. This cytoskeleton-based exploration is achieved by stochastic switching, with microtubules and filopodia alternating between growing and shortening phases apparently at random. If stabilizing signals are not detected during the growth phase, then the structures switch to a shortening state, from which they can again return to a growth phase, and so forth. A useful means of characterizing these stochastic processes in a model-independent way is by autocorrelation and spectral analysis. Previously, we compared experiment to theory by performing Monte Carlo simulations and computing the autocorrelation function and power spectrum from the simulated dynamics, an approach that is computationally intensive and requires recalculation whenever model parameters are changed. Here we present analytical expressions for the autocorrelation function and power spectrum, which compactly characterize microtubule and filopodial dynamics based on the stochastic, two-state model. The model assumes that the phase times are of variable duration and gamma-distributed, consistent with experimental evidence for microtubules assembled in vitro from purified tubulin. The analytical expressions permit the precise quantitative characterization of changes in microtubule and filopodial searching behavior corresponding to changes in the shape of the gamma distribution.
Positron annihilation in n- and p-type, B- and P-doped silicon crystals of 100 and 111 orientations☆

Abstract Positron annihilation spectra are compared for oriented and doped silicon crystals. A critical three-component deconvolution analysis of the lifetime spectra resulted in a previously undetected lifetime of ∼60 psec and ∼25% relative intensity. The sensitivity of the lifetimes to the details of analysis is discussed.
Outsiders and strangers: an archaeology of liminality in West Africa

I am a Mesoamericanist, not an Africanist. I shall therefore not attempt to address the fine points of West African archaeology and history that form the general substance of this book. I am, howev...
Isotope fractionation by chemical diffusion between molten basalt and rhyolite

Abstract Experimental diffusion couples were used to study chemical diffusion between molten rhyolite and basalt with special emphasis on the associated fractionation of calcium and lithium isotopes. Diffusion couples were made by juxtaposing firmly packed powders of a natural basalt (SUNY MORB) and a natural rhyolite (Lake County Obsidian) and then annealing them in a piston cylinder apparatus for times ranging from 0.1 to 15.7 h, temperatures of 1350–1450°C, and pressures of 1.2–1.3 GPa. Profiles of the major elements and many trace elements were measured on the recovered quenched glasses. The diffusivities of all elements except lithium were found to be remarkably similar, while the diffusivity of lithium was two to three orders of magnitude larger than that of any of the other elements measured. Chemical diffusion of calcium from molten basalt into rhyolite was driven by a concentration ratio of ∼18 and produced a fractionation of 44Ca from 40Ca of about 6 ‰. Because of the relatively low concentration of lithium in the natural starting materials a small amount of spodumene (LiAlSi2O6) was added to the basalt in order to increase the concentration difference between basalt and rhyolite, which was expected to increase the magnitude of diffusive isotopic fractionation of lithium. The concentration ratio between Li-doped basalt and natural rhyolite was ∼15 and the resulting diffusion of lithium into the rhyolite fractionated 7Li from 6Li by about 40‰. We anticipate that several other major rock-forming elements such as magnesium, iron and potassium will also exhibit similarly larger isotopic fractionation whenever they diffuse between natural melts with sufficiently large differences in the abundance of these elements.
Effect of osmolarity on in vitro development of rabbit embryos in a chemically defined medium

Abstract Rabbit embryos were cultured from the 2- to 4-cell stage in a modified Ham's F-10 defined medium prepared so as to give calculated osmolarities of 230, 250, 270, 290, 310 and 330 mOsm. After 120 h in culture, the number of embryos reaching the blastocyst stage in the 270 mOsm medium was significantly (P
Field evaluation of a risk awareness and perception training program for younger drivers

This study is an evaluation of a Risk Awareness and Training Program (RAPT) designed for younger drivers. Our prior study demonstrated that a version of RAPT improved the risk perception of younger, novice drivers in a driving simulator as indicated by their eye-fixations in critical situations. The current evaluation was carried out in the field, comparing a group of younger drivers (18-21 years old) trained with RAPT with an untrained group of the same age-range. Each driver was fitted with a head-mounted portable eye-tracker that collected data during the drive (a pre-determined course of approximately 16 miles that had ten critical locations similar in concept to the scenarios in the training session). The drivers' eye-movement data, especially point of gaze, were analyzed at these ten locations. There was a significant improvement in risk perception (as indexed by fixations on pre-determined areas of potential risk) for drivers who had completed RAPT. This is the first study to show that training of any kind can have an effect on drivers' detection of risky areas in the field. Language: en
RAD51 as a candidate parathyroid tumour suppressor gene on chromosome 15q: absence of somatic mutations

OBJECTIVE Loss of heterozygosity (LOH) at chromosome 15q is frequent in parathyroid adenomas, but no tumour suppressor gene of importance to parathyroid tumour development has been isolated from this region. The RAD51 gene has been localized to chromosome 15q and possesses regulatory functions involving DNA stability and cell proliferation, suggesting its possible role in tumorigenesis. Additionally, mutations in the RAD51 gene cause reduced resistance to ionizing radiation, which is a major risk factor for primary hyperparathyroidism. RAD51 was therefore analysed as a candidate tumour suppressor gene in a group of parathyroid adenomas for which mutations in a 15q tumour suppressor should be most readily detectable. PATIENTS AND DESIGN From a total of 55 parathyroid adenomas, nine were selected based on their LOH pattern showing DNA loss at chromosome 15q in the vicinity of the RAD51 gene. RAD51 mRNA expression was investigated by reverse transcription–polymerase chain reaction (RT-PCR), and sequence analysis of the entire coding region of the RAD51 cDNA was performed in all nine adenomas. RESULTS RAD51 mRNA expression was substantiated in all parathyroid adenomas. Compared with the normal RAD51 cDNA sequence, no point mutations or microdeletions could be found in the parathyroid tumor cDNA. CONCLUSION These observations suggest that somatic inactivating mutations of the RAD51 gene are uncommonly, if ever, associated with parathyroid tumourigenesis.
Adenosis of the prostate: A dysplastic lesion that can be confused with prostate adenocarcinoma

A ten-year period, 1966 through 1975, provided 2842 prostate specimens at The Wesley Medical Center, These specimens were classified as (1) adenocarcinoma, (2) adenosis, or (3) hyperplasia. During a follow-up period of 5--15 years (average 7.7 years), prostate carcinoma developed in seven of 108 patients (6.5%) with adenosis. During the same follow-up period prostate carcinoma developed in at least 84 of 2263 patients (3.7%) with hyperplasia. Adenosis is considered to be a dysplastic lesion because patients with histologic lesions limited to adenosis have approximately the same likelihood of prostate carcinoma developing as patients with hyperplasia.
Development of a remotely sensed, historical land-cover change database for rural Chihuahua, Mexico

Abstract The purpose of this article is to describe the development of a remotely sensed, historical land-cover change database for the northwestern quarter of Chihuahua, Mexico, The database consists of multi-temporal land-cover classifications and change detection images. The database is developed to facilitate future investigations that examine urban–rural linkages as possible drivers of rural land-use and land-cover changes. To develop the needed land-cover change database, this study uses the North American Landsat Characterization (NALC) MSS triplicates because of their temporal depth and spatial breadth. Challenges exist, however, to effective classification and change detection using the NALC triplicates, including illumination differences across multiple scenes and periods caused by topographic and solar variations and the lack of ground reference data for historic periods. Therefore, creation of the database is a four step process. First, extensive pre-processing is performed to enhance comparability of multi-date images. Pre-processing includes topographic correction, mosaic creation and multi-date radiance normalization. Second, ancillary sources of land-cover data are combined with visual interpretations of enhanced images to define reference pixels used to classify the images using the maximum likelihood algorithm. Third, classification accuracy is assessed. Fourth, post-classification change detection is performed. Results indicate significant image improvements after pre-processing that permit very good overall classification (86.26% classified correctly) and change detection. To conclude, findings are presented that indicate significant changes to arid grasslands/shrublands and forest resources in mountainous regions.
Applying Usability Engineering Principles to the Design and Testing of Warning Messages

Very little has been published on methods for creating and testing text messages for product warnings. This paper describes how the three main principles of usability engineering (prototyping, empirical user testing, and iterative design) can be applied to the design and evaluation of warning text. Pre-prototype activities that help define the warning requirements are described, followed by a discussion of guidelines for creating and testing design prototypes. Finally, a methodology for formally testing the effectiveness of warning text is presented. The procedure described should be useful to human factors practitioners who are responsible for creating or evaluating textual warnings.
If You Want to Improve Your Company, Get Out

…of your office, that is. Here are some tips for reaching your employees, your sales force, your customers, and your industry peers.
Identifying, Removing Architectural Barriers.

Complying with federal regulations concerning equal ducational opportunities for the handicapped can be a complicated and expensive proposition. This author suggests that use of local school personnel and students is an economical approach to meeting such regulations.
Stochastic ensembles, conformationally adaptive teamwork, and enzymatic detoxification

It has been appreciated for a long time that enzymes exist as conformational ensembles throughout multiple stages of the reactions they catalyze, but there is renewed interest in the functional implications. The energy landscape that results from conformationlly diverse poteins is a complex surface with an energetic topography in multiple dimensions, even at the transition state(s) leading to product formation, and this represents a new paradigm. At the same time there has been renewed interest in conformational ensembles, a new paradigm concerning enzyme function has emerged, wherein catalytic promiscuity has clear biological advantages in some cases. "Useful", or biologically functional, promiscuity or the related behavior of "multifunctionality" can be found in the immune system, enzymatic detoxification, signal transduction, and the evolution of new function from an existing pool of folded protein scaffolds. Experimental evidence supports the widely held assumption that conformational heterogeneity promotes functional promiscuity. The common link between these coevolving paradigms is the inherent structural plasticity and conformational dynamics of proteins that, on one hand, lead to complex but evolutionarily selected energy landscapes and, on the other hand, promote functional promiscuity. Here we consider a logical extension of the overlap between these two nascent paradigms: functionally promiscuous and multifunctional enzymes such as detoxification enzymes are expected to have an ensemble landscape with more states accessible on multiple time scales than substrate specific enzymes. Two attributes of detoxification enzymes become important in the context of conformational ensembles: these enzymes metabolize multiple substrates, often in substrate mixtures, and they can form multiple products from a single substrate. These properties, combined with complex conformational landscapes, lead to the possibility of interesting time-dependent, or emergent, properties. Here we demonstrate these properties with kinetic simulations of nonequilibrium steady state (NESS) behavior resulting from energy landscapes expected for detoxification enzymes. Analogous scenarios with other promiscuous enzymes may be worthy of consideration.
Phase-sensitive particle separation using alternating longitudinal electric field

Particles with different charge-to-mass ratios can be separated in a phase-sensitive process with application of a simple alternating longitudinal electric field in the absence of other electric or magnetic fields. The method suggests that a given particle can either be isolated or eliminated from a beam of several charged particles, in contrast to the conventional mass spectrometry where a particular particle is isolated. The method, based on the principles underlying phase stability in particle accelerators, could be applied to mass spectrometry or selective ion sources for plasma generation, ion traps, sputtering, or other applications. It would be especially useful in instances where the incoming ions are timed in synchrony with the proper phase of the applied voltage.
Thermal conductivity of superlattices

The lattice thermal conductivity of superlattices is shown to depend on a new kind of umklapp scattering process, called a mini-umklapp, associated with the mini-Brillouin zone of the superlattice. Expressions for three-phonon mini-umklapp-scattering matrix elements are obtained for superlattices consisting of lattice-matched simple-cubic layers. The temperature dependence of the thermal conductivity is evaluated using an extension of Callaway's phenomenological model.
Updating the Determinants of Firm Performance: Estimation using the 1998 UK Workplace Employee Relations Survey

We examine the determinants of establishment performance in the UK, using cross-sectional data from the 1998 Workplace Employee Relations Survey to replicate research by Fernie and Metcalf (1995) who used data from the 1990 Workplace Employee Relations Survey; specifically, we test whether employee representation, contingent pay and efforts to boost employee participation affect a set of economic and industrial relations outcome indicators in the manner they suggest. We also re-estimate the influential WERS90-based study of Machin and Stewart (1996) on the links between union status and financial performance. In both cases we report very different results.