cssi/SciSciGPT-SciSciNet huggingface dataset:
Progression of asymptomatic carotid stenosis: a natural history study in 1004 patients.

Abstract Purpose: The purpose of this study was to delineate the natural history of the progression of asymptomatic carotid stenosis. Methods: In a 10-year period, 1701 carotid arteries in 1004 patients who were asymptomatic were studied with serial duplex scans (mean follow-up period, 28 months; mean number of scans, 2.9/patient). At each visit, stenoses of the internal carotid artery (ICA) and the external carotid artery (ECA) were categorized as none (0 to 14%), mild (15% to 49%), moderate (50% to 79%), severe (80% to 99%), preocclusive, or occluded. Progression was defined as an increase in ICA stenosis to ≥50% for carotid arteries with a baseline of Results: The risk of progression of ICA stenosis increased steadily with time (annualized risk of progression, 9.3%). With multivariate modeling, the four most important variables that affected the progression ( P P Conclusion: In contrast to recently published studies, we found that the risk of progression of carotid stenosis is substantial and increases steadily with time. Baseline ICA stenosis was the most important predictor of the progression, but baseline ECA stenosis also was identified as an important independent predictor. Contralateral ICA stenosis and systolic hypertension were additional significant predictors. We found further that the progression of ICA stenosis correlated with ischemic neurologic events but not baseline stenosis. The data provide justification for the use of serial duplex scans to follow carotid stenosis and suggest that different follow-up intervals may be appropriate for different patient subgroups. (J Vasc Surg 1999;29:208-16.)
Spectral convergence of self-adjoint operators and generalized wave operators

Abstract It is well known that if the difference of self-adjoint operators A and B is of trace class, then the generalized wave operators W ± ( B , A ) = s -lim t → ± ∞ exp( itB ) exp(− itA ) P ac ( A ) exist. We give a sufficient condition for s -lim n → ∞ W ± ( B n , A n ) = W ± ( B , A ) when sequences of operators are considered. The condition involves the convergence of the spectral density of A n . Examples of operators with this property are given. This investigation is also related to the absolute continuity of self-adjoint Operators.
Polydisperse polymers: Relations among molecular weight distribution, stress relaxation, and distribution of relaxation times

Relaxation times in polydisperse polymers were calculated on the basis of more realistic viscosity mixing rules than have previously been used. These relaxation times and mixing rules are in turn used to calculate viscoelastic functions such as stress relaxation following sudden straining or steady shearing. Inversion of these functions provides an accurate way to estimate the molecular weight distribution. This method is useful for insoluble or otherwise intractable polymers.
Dynamic changes in microtubule configuration correlate with nuclear migration in the preblastoderm Drosophila embryo

Drosophila embryogenesis is initiated by a series of syncytial mitotic divisions. The first nine of these divisions are internal, and are accompanied by two temporally distinct nuclear movements that lead to the formation of a syncytial blastoderm with a uniform monolayer of cortical nuclei. The first of these movements, which we term axial expansion, occurs during division cycles 4-6 and distributes nuclei in a hollow ellipsoid underlying the cortex. This is followed by cortical migration, during cycles 7-10, which places the nuclei in a uniform monolayer at the cortex. Here we report that these two movements differ in their geometry, velocity, cell-cycle dependence, and protein synthesis requirement. We therefore conclude that axial expansion and cortical migration are mechanistically distinct, amplifying a similar conclusion based on pharmacological data (Zalokar and Erk, 1976). We have examined microtubule organization during cortical migration and find that a network of interdigitating microtubules connects the migrating nuclei. These anti-parallel microtubule arrays are observed between migrating nuclei and yolk nuclei located deeper in the embryo. These arrays are present during nuclear movement but break down when the nuclei are not moving. We propose that cortical migration is driven by microtubule-dependent forces that repel adjacent nuclei, leading to an expansion of the nuclear ellipsoid established by axial expansion.
The ontological foundation of Russell's theory of modality

Prominent thinkers such as Kripke and Rescher hold that Russell has no modal logic, even that Russell was indisposed toward modal logic. In Part I, I show that Russell had a modal logic which he repeatedly described and that Russell repeatedly endorsed Leibniz's multiplicity of possible worlds. In Part II, I describe Russell's theory as having three ontological levels. In Part III, I describe six Parmenidean theories of being Russell held, including: literal in 1903; universal in 1912; timeless in 1914; transcendental in 1918–1948. The transcendental theory underlies the primary level of Russell's modal logic. In Part IV, I examine Rescher's view that Russell and modal logic did not mix.
Does variable step size ruin a symplectic integrator

Abstract There exist methods that preserve the symplectic invariants of Hamiltonian systems when fixed step size is used. It is proved that the most simple-minded version of this property is lost if the step size is varied.
A dual-probe recognition memory task for use during sustained operations

Although memory has been shown to be greatly affected by sleep loss, there is an absence of data on the effect of sustained work on recognition memory. This is unfortunate because recognition, unlike free recall, can be analyzed to separate effects on memory sensitivity from effects on report bias. Based upon work with single-probe recognition memory tasks, we developed a clual-probe recognition task for practical use in sustained work paradigms. The task requires 20 min to complete and yields an array of performance variables that can be used to conduct signal detection analyses, to assess serial-position effects, and to evaluate speed-accuracy functions.
Runtime organization for the Ada language system programs

The runtime organization provides the execution environment for generated code of a source program. The runtime organization includes the primitive data elements, such as scalar and composite data objects; system data elements, such as stack and heaps; and a runtime system to provide functionality not supported in the target computer. In effect the runtime organization provides an abstract or virtual machine.This paper is a brief overview of the runtime organization that is the execution environment for the code generated by the Ada compiler in the Army Ada Language System. Since this compiler translates the full Ada language, the runtime organization must provide support not normally found in other languages, such as exception handling and tasking. As retargetability is a major goal of the Ada Language System, the runtime organization must also exist on many targets, both with or without an operating system support. While this paper specifically describes the runtime organization for the VAX/VMS 11/780, it does explore the design flexibility that enables the design to support generated code over a variety of targets.
The neuron classification problem

A systematic account of neuron cell types is a basic prerequisite for determining the vertebrate nervous system global wiring diagram. With comprehensive lineage and phylogenetic information unavailable, a general ontology based on structure-function taxonomy is proposed and implemented in a knowledge management system, and a prototype analysis of select regions (including retina, cerebellum, and hypothalamus) presented. The supporting Brain Architecture Knowledge Management System (BAMS) Neuron ontology is online and its user interface allows queries about terms and their definitions, classification criteria based on the original literature and "Petilla Convention" guidelines, hierarchies, and relations-with annotations documenting each ontology entry. Combined with three BAMS modules for neural regions, connections between regions and neuron types, and molecules, the Neuron ontology provides a general framework for physical descriptions and computational modeling of neural systems. The knowledge management system interacts with other web resources, is accessible in both XML and RDF/OWL, is extendible to the whole body, and awaits large-scale data population requiring community participation for timely implementation.
Simulation of double layers in a model auroral circuit with nonlinear impedance

A reduced circuit description of the U-shaped potential structure of a discrete auroral arc, consisting of the flank transmission line plus parallel-electric-field region, is used to provide the boundary condition for one-dimensional simulations of the double-layer evolution. The model yields asymptotic scalings of the double-layer potential, as a function of an anomalous transport coefficient alpha and of the perpendicular length scale l(a) of the arc. The arc potential phi(DL) scales approximately linearly with alpha, and for alpha fixed phi (DL) about l(a) to the z power. Using parameters appropriate to the auroral zone acceleration region, potentials of phi (DPL) 10 kV scale to projected ionospheric dimensions of about 1 km, with power flows of the order of magnitude of substorm dissipation rates.
Bayesian reconstruction of P(r) directly from two-dimensional detector images via a Markov chain Monte Carlo method

The interatomic distance distribution, P(r), is a valuable tool for evaluating the structure of a molecule in solution and represents the maximum structural information that can be derived from solution scattering data without further assumptions. Most current instrumentation for scattering experiments (typically CCD detectors) generates a finely pixelated two-dimensional image. In contin­uation of the standard practice with earlier one-dimensional detectors, these images are typically reduced to a one-dimensional profile of scattering inten­sities, I(q), by circular averaging of the two-dimensional image. Indirect Fourier transformation methods are then used to reconstruct P(r) from I(q). Substantial advantages in data analysis, however, could be achieved by directly estimating the P(r) curve from the two-dimensional images. This article describes a Bayesian framework, using a Markov chain Monte Carlo method, for estimating the parameters of the indirect transform, and thus P(r), directly from the two-dimensional images. Using simulated detector images, it is demonstrated that this method yields P(r) curves nearly identical to the reference P(r). Furthermore, an approach for evaluating spatially correlated errors (such as those that arise from a detector point spread function) is evaluated. Accounting for these errors further improves the precision of the P(r) estimation. Experimental scattering data, where no ground truth reference P(r) is available, are used to demonstrate that this method yields a scattering and detector model that more closely reflects the two-dimensional data, as judged by smaller residuals in cross-validation, than P(r) obtained by indirect transformation of a one-dimensional profile. Finally, the method allows concurrent estimation of the beam center and D max, the longest interatomic distance in P(r), as part of the Bayesian Markov chain Monte Carlo method, reducing experimental effort and providing a well defined protocol for these parameters while also allowing estimation of the covariance among all parameters. This method provides parameter estimates of greater precision from the experimental data. The observed improvement in precision for the traditionally problematic D max is particularly noticeable.
A Single Nucleotide Linked to a Switch in Metal Ion Reactivity Preference in the HDV Ribozymes

The two ribozymes of hepatitis delta virus (HDV) cleave faster in divalent metal ions than in monovalent cations, and a variety of divalent metal ions can act as catalysts in supporting these higher rates. Although the ribozymes are closely related in sequence and structure, they display a different metal ion preference; the genomic form cleaves moderately faster in Mg2+ than in Ca2+ while the reverse is true for the antigenomic ribozyme. This difference raises questions about understanding the catalytic role of the metal ion in the reaction. We found that the metal ion reactivity preference correlated with the identity of a single nucleotide 5‘ of the cleavage site (−1 position). It is a U in the genomic sequence and a C in the antigenomic sequence. With both ribozymes, the reactivity preference for Mg2+ and Ca2+ could be reversed with a change at this position (C to U or U to C). Moreover, with an A at position −1, there was a relative increase in cleavage rates in low concentrations of Mn2+ for both ri...
Contextualizing Archaeology’s “Locals”: A Scalar Approach from El Tajín, Mexico

In this article, I build on critiques of the “local” trope in archaeology by suggesting that the scalar dimensions of the “local“ are worth considering in terms of recent thinking on scale in human geography, particularly in the work of Richard Howitt. Employing Howitt’s conception of scale as size, level, and relation, I develop a case study centered on the archaeological site of El Tajin. A scale-sensitive analysis yields federal administration, local intervention, and archaeological practice as topics for study, and I trace their developments and contestations over the course of the 20th century with reference to Howitt’s categories. I conclude by arguing for closer attention to scale in locally oriented archaeology.
The retinofugal fibers and their terminal nuclei in Galago crassicaudatus (primates).

Control and experimental brains of Galago were used to study the subcortical optic nuclei and their retinal input. Weil, Nissl and Fink-Heimer methods were employed. The pregeniculate nucleus receives predominantly contralateral retinal input. Terminal degeneration is found only in its pars grisea, but not in its pars fibrosa. The lateral geniculate nucleus exhibits seven demonstrable laminae. Laminae 0, 2, 3 and 4 receive ipsilateral retinal input, whereas laminae 1, 5 and 6 receive contralateral input without overlap. In Fink-Heimer preparations only the ipsilateral lamina 4 and the contralateral lamina 5 show clusters of argyrophilic spherules which probably indicate axo-dendritic termination of retinofugal fibers. The nucleus praetectalis posterior and nucleus tractus optici receive predominantly contralateral retinal input. In all likelihood, only the stratum griseum superficiale of the superior colliculus receives retionfugal fibers. On the basis of the very remarkable pattern of terminal degeneration, we divide this stratum into substrata A, B and C. The ipsilateral superior colliculus receives retinal input to its substratum B and the contralateral superior colliculus receives retinal input to its substratum A only. Substratum C receives probably no retinal input.
The influence of temperature on egg size and variation in Drosophila melanogaster.

1. Fliegen (Drosophila melanogaster) wurden fur Generationen unter kontrollierten Bedingungen bei einer Temperatur von 23‡ C gezogen; die Eier, die von einpaarigen Zuchten abgelegt wurden, wurden bis zum Tode der Mutterfliegen gemessen. Die biometrischen Konstanten der Eilange zeigten:
Comment on “New Insights in the Electrocatalytic Proton Reduction and Hydrogen Oxidation by Bioinspired Catalysts: A DFT Investigation”

In the title paper, Vetere et al. reported a computational investigation of the mechanism of H2 oxidation/proton reduction using a model of nickel-based electrocatalysts that incorporates pendant amines in cyclic phosphorus ligands. These catalysts are attracting considerable attention owing to their high turnover rates and relatively low overpotentials. These authors interpreted the results of their calculations as evidence for a symmetric bond cleavage of H2 leading directly to two protonated amines in concert with a two-electron reduction of the Ni(II) site to form a Ni(0) diproton state. Proton reduction would involve a reverse symmetric bond formation. We report here an analysis that refutes the interpretation by these authors. We give, for the same model system, the structure of a heterolytic cleavage transition state consistent with the presence of the Ni(II) center acting as a Lewis acid and the pendant amines acting as Lewis bases. We present the associated intrinsic reaction coordinate (IRC) pat...
P38 Activation Mediates Amyloid-β Cytotoxicity

Amyloid-β is a leading candidate factor in the development of Alzheimer disease (AD), however the mechanisms involved are unclear. As such, there has been considerable interest in evidence showing that the neuronal damage caused by amyloid-β is mediated by oxidative stress. Notably, oxidative stress leads to activation of stress-activated protein kinases, which we and others have shown are also involved in AD pathogenesis. One SAPK in particular, p38, appears to be crucial in AD and therefore, in the current study, we investigated the role of p38 activation in amyloid-β cytotoxicity. Our data showed p38 activation was induced by amyloid-β in a concentration-dependent manner in M17 human neuroblastoma cells. Notably, amyloid-β toxicity was significantly decreased by inhibition of p38 activity by overexpressing dominant negative p38. Consistent with this, in primary cortical neurons amyloid-β also induced p38 activation and amyloid-β toxicity was significantly diminished when p38 was inhibited by its specific inhibitor, SB203580. Taken together, these data suggest that p38 is a key downstream effector of amyloid-β-induced neuronal death and blocking this pathway may be of therapeutic value.
Dog Bites Boy: Judgments of Blame and Shame

Separate samples of undergraduates read matched stories about a dog or a boy actor biting a child; others read about a dog or a boy playing with a child. Rating scales were used to obtain evaluatio...
Aspects of risk-aversion in foraging white-crowned sparrows

Abstract Two series of aviary experiments with white-crowned sparrows (Zonotrichia leucophrys) are reported. The first series attempts to mimic foraging choices between microhabitats. The second series examines foraging choices made within a single artificial patch, a design intended to resemble dietary selection. In all experiments subjects chose between a constant food reward and a variable reward, the mean of which equalled the constant reward. Each experiment allowed the bird to feed at an overall rate greater than that minimally required for daily energy balance. In both series of experiments, the birds usually preferred the constant reward. Results of the first series do not differ significantly from previously reported preferences of dark-eyed juncos (Junco hyemalis), birds weighing 10 g less than the white-crowned sparrows.
Discrete-phase simulation of single bubble rise behavior at elevated pressures in a bubble column

Abstract Numerical simulation is performed on the flow behavior of a bubble rising in a liquid medium at high pressures. In the numerical scheme, a computational fluid dynamics (CFD) method is used to account for the flow characteristics of the continuous liquid phase and the gas phase inside the bubble. The volume tracking based on the volume-of-fluid (VOF) method is used to describe the free surface motion of gas bubble, and the deformational bubble shapes. Simulations are performed simultaneously for both liquid and gas phases by considering the volume-fraction-weighted averaged properties on the interface. The behavior of a single gas bubble rising in Paratherm NF heat transfer liquid at pressures of 0.1 and 19.4 MPa is simulated and compared with the experimental results obtained in this study. The comparison is satisfactory. The results of the simulation indicate that as the pressure increases, the maximum stable bubble size decreases, which is in conformity with the experimental findings.
Macroeconomic Volatility: The Role of the Informal Economy

Many countries have a large informal economy that is poorly measured in the national accounts. I develop a two-sector small open economy business cycle model where one sector is formal and the other is informal, and explore the effect that the informal sector has on measured business cycles. I show that if the informal economy is poorly measured, the model can generate a volatility of measured consumption that is higher than that of output, as observed in many developing countries and some developed countries, even though actual consumption is not nearly as volatile. My results illustrate the importance of the informal sector and its mis-measurement in understanding measured cyclical fluctuations.
Variability of the Volume of Isoflow

Twenty healthy hospital workers produced maximal expiratory flow-volume curves before and after three vital capacity inhalations of an 80 percent helium and 20 percent oxygen mixture (HE+O 2 ) in the morning and afternoon for four days during one week. Ten healthy trade union apprentices underwent the same tests, twice on one day and again one month later. Measurements made from curves (and their mean coefficients of variation) were: Viso V ˙ (105 percent), FVC (3 percent), FEF50% (6 percent), FEF75% (8 percent), the ratio of FEF50% breathing He+O 2 to FEF50% breathing air (6 percent), and the ratio of FEF75% breathing He+O 2 to FEF75% breathing air (9 percent). Differences among separate observers contributed significantly to the high variability of the Viso V ˙ . Diurnal changes and training effects over the week of study were not significant In conclusion, Viso V ˙ is poorly reproducible compared with the FVC and expiratory flow rates at low lung volumes breathing air and He+O 2 . This should be considered when interpreting results in a given individual.
Responses to sucrose and glutamine by soybean embryos grown in vitro

Immature soybean (Glycine max [L.] Merr. cv. Ransom) embryos were grown in vitro in the presence of different concentrations of sucrose and glutamine to examine how availability of carbohydrate and nitrogen affects dry matter accumulation and embryo composition. Embryos were transferred to fresh medium every 4 days to maintain sucrose and glutamine concentrations of the culture medium. In all experiments, accumulation of dry matter and protein content increased when the sucrose concentration of the culture medium was increased from 1.5 to 150 mM: however, a relatively greater enhancement of dry matter than of protein accumulation resulted in a lower protein concentration at 150 than at 1.5 mM sucrose. Both content and concentration of protein were increased by the increases in glutamine supply to concentrations exceeding 68% protein at 120 mM glutamine. In combination with 150 mM sucrose, however, oil increased as glutamine supply was increased from 0.6 to 6 mM and then decreased as glutamine supply was increased from 6 lo 120 mM. Varying the concentration of sucrose available during seed development also affected embryo composition. Decreased availability of sucrose during either the early or late portion of the culture period resulted in lower accumulation of dry mailer as well as oil. Protein concentration was actually higher for embryos transferred from 150 to 1.5 nM sucrose than for those remaining in 150 mM throughout the culture period: however, the greater percentage of protein was due lo a decrease in accumulation of dry weight. In addition, embryo composition was affected by altering the availability of glutamine during culture, indicating that variation in the level of nitrogen assimilate delivered during seed development can change embryo composition. Decreasing the glutamine concentration of the medium lowered both protein and oil content. In contrast, increasing the glutamine concentration of the medium from 0.6 to 6 mM 8 days after initiation of culture increased the protein content and concentration of the embryo while oil content was not affected.
Dimensions of Intervention for Student Development

(1982). Dimensions of Intervention for Student Development. The Journal of Higher Education: Vol. 53, No. 5, pp. 600-603.
Characterization of the Stat5 protease.

Immature myeloid cells have been shown to transduce signals through a carboxyl-terminally truncated isoform of Stat5. This functionally distinct signal transducer and activator of transcription isoform is generated through a unique protein-processing event. Evaluation of numerous cell lines has determined that there is a direct correlation between the expression of truncated Stat5 and protease activity. Moreover, protease activity is found only in the myeloid and not in lymphoid progenitors. To further characterize the protease small quantities have been purified to near homogeneity. Studies on this purified material indicate that the protease has an apparent molecular mass of approximately 25 kDa and is active over a wide range of pH values. The protease will also cleave both activated (i.e. tyrosine-phosphorylated) and inactivate Stat5. Although this activity is sensitive to phenylmethylsulfonyl fluoride, it is notably not sensitive to several other serine protease inhibitors. Additional studies have led to the identification of the unique site where the protease cleaves Stat5. Mutagenesis of this site renders Stat5 resistant to cleavage. Consistent with the model that Stat5 cleavage is important for early myeloid development, introduction of a "non-cleavable" isoform of Stat5 into FDC-P1 cells (a myeloid progenitor line) leads to significant phenotypic changes.
Correlates of concurrent energy drink and alcohol use among socially active adults.

Background: Research indicates that energy drink consumption and the combined use of energy drinks and alcohol are popular among young adults, although this research has typically focused on college students. Because of the potential for harms associated with this combination, it is critical to understand use among adults in nightlife scenes who may be most at risk for harms associated with combined energy drink and alcohol consumption. Objectives: By focusing our sample on individuals in a range of nightlife scenes, we aim to gain a deeper understanding of the demographic factors associated with energy drink use and combined energy drink and alcohol consumption to benefit the targeting of intervention and prevention efforts beyond college campuses. Methods: Using a field-based survey in New York City to survey adults active in various nightlife scenes, this study reports on the survey results of 1476 venue patrons at venues in five nightlife scenes in addition to college bar scenes. Results: Men, younger...
An Insect Respirometer.

In the course of some studies on house flies, it became desirable to determine the respiratory exchange of individuals. Since the metabolism of such insects is low, a fairly sensitive apparatus was required. Existing micro-respirometers were not well adapted for use with whole active insects, consequently the apparatus described herein was constructed.
Field-induced migration of sodium in soda silicate glasses during scanning electron microscopy

The changes in chemical composition to soda silicate glass during scanning electron microscopy have been investigated. The loss of sodium from the irradiated region was measured using x-ray wavelength spectroscopy and subsequently modelled assuming field-assisted ionic migration. There is excellent agreement for both 20 keV and 10 keV electrons, although a radiolytic effect must probably be included to fully describe the depletion phenomenon.
Performance analysis of CR-honeynet to prevent jamming attack through stochastic modeling

Abstract Cognitive Radio Network (CRN) has to stall its packet transmission periodically to sense the spectrum for Primary User’s (PU’s) transmission. The limited and dynamically available spectrum and fixed periodic schedule of transmission interruption makes it harder to model the performance of a CRNs. Again, an open and dynamic spectrum access model brings forth a serious challenge of sustenance among the CRN and makes them more susceptible to jamming-based denial of service (DoS) attacks. Inspired by honeypot in the network security, we propose a honeynet based defense mechanism called CR-honeynet. CR-honeynet aims to avoid attacks on legitimate communications by dedicating a Secondary User (SU) as a honeynode, to deter the attacker from attacking legitimate SUs and attack the honeynode instead. Dedicating an SU as honeynode, on account of its permanent idleness, is wasteful of an entire node as a resource. We seek to resolve the dilemma by dynamically selecting the honeynode for each transmission period. The contribution of the current paper is two-fold. Initially, we develop the first comprehensive queuing model for CRNs, which pose unique modeling challenges, due to their fixed periodic sensing and transmission cycles. In the second step, we introduce a series of strategies for honeynode selection to combat these attacks while keeping the CRN’s performance optimal for different traffic scenarios. We build a simulation of a CRN under jamming attack and analyze its performance with different honeynode selection strategies. We find that the predictions, of our mathematical model, track closely with the results of our simulation experiments.
An approach for temporal analysis of email data based on segmentation

Many kinds of information are hidden in email data, such as the information being exchanged, the time of exchange, and the user IDs participating in the exchange. Analyzing the email data can reveal valuable information about the social networks of a single user or multiple users, the topics being discussed, and so on. In this paper, we describe a novel approach for temporally analyzing the communication patterns embedded in email data based on time series segmentation. The approach computes egocentric communication patterns of a single user, as well as sociocentric communication patterns involving multiple users. Time series segmentation is used to uncover patterns that may span multiple time points and to study how these patterns change over time. To find egocentric patterns, the email communication of a user is represented as an item-set time series. An optimal segmentation of the item-set time series is constructed, from which patterns are extracted. To find sociocentric patterns, the email data is represented as an item-setgroup time series. Patterns involving multiple users are then extracted from an optimal segmentation of the item-setgroup time series. The proposed approach is applied to the Enron email data set, which produced very promising results.
Immunohistochemical detection of p53 protein accumulation in head and neck cancer: correlation with p53 gene alterations

The genetic and functional status of the p53 gene may be an important factor in guiding therapeutic strategies for patients with cancer. The purpose of this study was to determine whether p53 immunohistochemistry (IHC) accurately reflects the mutational status of the p53 gene and to determine whether p53 IHC independently predicts tumor responsiveness to radiation therapy for patients with HNSCC. p53 IHC was performed using the monoclonal antibody DO7 on tumors from 85 patients with HNSCC treated with primary or adjuvant radiation. The p53 status in all of these tumors was previously assessed by direct sequence analysis of exons 5 through 9: 49 tumors were p53 wild-type, and 36 harbored p53 gene mutations. All patients were well characterized with respect to locoregional recurrence, distant spread, and survival. Positive p53 staining was observed in 53 of the 85 cases (62%). Only 27 (51%) of these 53 IHC-positive cases harbored gene mutations in exons 5 through 9; 23 (72%) of the 32 IHC-negative cases did not harbor mutations. The overall correlation rate between IHC and sequencing was 59% (P < .04, chi2). Discordant results were observed for 35 (41%) cases, including 26 IHC-positive cases and 9 IHC-negative cases. In 7 of 9 cases, false-negative staining was due to a nonsense or splice-site mutation. p53 IHC was not predictive of overall survival (P = .37) or disease-free survival (P = .95). In a sizable number of cases, p53 IHC does not reflect the mutational status of the p53 gene. Specific types of alterations (eg, truncating mutations) and other factors may contribute to this poor correlation. Moreover, p53 IHC does not appear to be an independent predictor of tumor responsiveness to radiation in patients with HNSCC.
Acute and chronic ethanol exposure alters the function of hippocampal kainate receptors expressed in Xenopus oocytes.

The effects of acute and extended ethanol exposure on N-methyl-D-aspartate- and kainate-induced currents were examined electrophysiologically in Xenopus oocytes expressing rat hippocampal mRNA. Ethanol inhibited responses stimulated by low and high concentrations of N-methyl-D-aspartate to a similar degree. However, responses produced by low or high concentrations of kainate were differentially inhibited by ethanol. Low kainate concentration responses were much more sensitive to ethanol than high kainate concentrations (e.g., 50 mM ethanol inhibited 12.5 microM kainate responses by 45% compared to 15% inhibition of 400 microM kainate responses). In oocytes cultured in 100 mM ethanol for 1-5 days, the ethanol inhibition of maximum N-methyl-D-aspartate and kainate responses was not different from that in non-ethanol-exposed oocytes. Ethanol treatment, however, selectively decreased the ethanol sensitivity of low kainate concentration responses. Currents stimulated by N-methyl-D-aspartate or kainate were not different between control and ethanol-treated oocytes, indicating that ethanol exposure did not interfere with channel expression. The selective actions of acute and extended ethanol exposure on low kainate responses may indicate selective actions of ethanol on subtypes of kainate receptors expressed in oocytes.
The effects of strength and power training on single-step balance recovery in older adults: a preliminary study

Improving muscle strength and power may mitigate the effects of sarcopenia, but it is unknown if this improves an older adult's ability to recover from a large postural perturbation. Forward tripping is prevalent in older adults and lateral falls are important due to risk of hip fracture. We used a forward and a lateral single-step balance recovery task to examine the effects of strength training (ST) or power (PT) training on single-step balance recovery in older adults. Twenty older adults (70.8±4.4 years, eleven male) were randomly assigned to either a 6-week (three times/week) lower extremity ST or PT intervention. Maximum forward (FLeanmax) and lateral (LLeanmax) lean angle and strength and power in knee extension and leg press were assessed at baseline and follow-up. Fifteen participants completed the study (ST =7, PT =8). Least squares means (95% CI) for ΔFLeanmax (ST: +4.1° [0.7, 7.5]; PT: +0.6° [-2.5, 3.8]) and ΔLLeanmax (ST: +2.2° [0.4, 4.1]; PT: +2.6° [0.9, 4.4]) indicated no differences between groups following training. In exploratory post hoc analyses collapsed by group, ΔFLeanmax was +2.4° (0.1, 4.7) and ΔLLeanmax was +2.4° (1.2, 3.6). These improvements on the balance recovery tasks ranged from ~15%-30%. The results of this preliminary study suggest that resistance training may improve balance recovery performance, and that, in this small sample, PT did not lead to larger improvements in single-step balance recovery compared to ST. Language: en
Gross Structure of the Fat Globule Membrane of Cow's Milk. II. Distribution of Amino Acids, Hexosamines, Ribonucleic Acid, Copper and Iron

Abstract Washed cream was stirred at 25C and centrifuged to separate the cream and aqueous layers. Water was added each time as the process was repeated until the cream phase inverted. The butter was melted and the aqueous portion isolated. All aqueous portions were centrifuged at 50,000× g for 90min at 4C. Each supernatant pH was adjusted to aggregate the lipoproteins. The outer layer of the membrane desorbed from the cream consisted of reddish-brown pellets high in protein, low in lipid, and a supernatant aggregate low in protein, high in lipid. The inner layer consisted of a pellet high in protein, low in lipid and a supernatant aggregate low in protein, high in lipid. An interfacial portion was high in protein, low in lipid. Amino acid compositions of the membrane fractions were uniform and indicated soluble and insoluble proteins in all fractions. Hexosamines were distributed throughout the membrane fractions, indicating glycoproteins in all fractions. Ribonucleic acid was distributed throughout the membrane, with the highest level in the inner layer supernatant aggregate. Iron was highest in the outer membrane layers, while copper was more evenly distributed.
Item Presentaton as an Influence on Questionnaire Validity: a Field Experiment

This study was concerned with the effects of questionnaire format on convergent and discriminant validity. Two types of formats were examined: the first with items measuring the same dimensions grouped together and the second with items measuring the same dimensions distributed randomly throughout the questionnaire. Sixty subjects completed questionnaires containing items from the Leader Behavior Description Questionnaire (Stogdill, 1963) and the Michigan Four-Factor Leadership Questionnaire (Taylor and Bowers, 1972); there were thirty subjects in each of the conditions (grouped and random). The random relative to the grouped condition showed superior convergent and discriminant validity, as assessed by both multitrait-multimethod and analysis of variance procedures. Implications for questionnaire validity are discussed.
Do we really know why chloroplast membranes stack

Abstract Although recent discoveries regarding the phosphorylation of a major light-harvesting protein in the chloroplast membrane have helped to explain the mechanism of membrane stacking, they have failed to explain the underlying reason for the phenomenon. It is suggested that the regulation of excitation energy distribution may not be the reason for membrane adhesion, but rather an adaptive response to stacked membrane organization.
Photic driving in the early premature infant.

Abstract Thirty-two infants born at gestational ages of 27–32 weeks were subjected to isolated flashes and intermittent photic stimulation. Their gestational age (GA) was assessed by maternal dates, physical examination and, when possible, examination of lens vasculature. The babies were selected for being of less than 33 weeks GA and being normal for GA on examination. Responses to isolated flashes were present in 63% and photic driving at 2–10 f/sec was present in 66% of the babies. Apparent discrepancies of these findings with previous reports about photic driving in prematures are discussed.
Numerical Modeling of the Atmosphere with an Isentropic Vertical Coordinate

A theta-coordinate model simulating the nonlinear evolution of a baroclinic wave is presented. In the model, vertical discretization maintains important integral constraints such as conservation of the angular momentum and total energy. A massless-layer approach is used in the treatment of the intersections of coordinate surfaces with the lower boundary. This formally eliminates the intersection problem, but raises other computational problems. Horizontal discretization of the continuity and momentum equations in the model are designed to overcome these problems. Selected results from a 10-day integration with the 25-layer, beta-plane version of the model are presented. It is concluded that the model can simulate the nonlinear evolution of a baroclinic wave and associated dynamical processes without major computational difficulties.
Building Framework for Nursing Scholarship: Guidelines for Appointment and Promotion

As nursing academia responds to shifts in nursing education—the emergence of clinically focused doctoral degrees and an emphasis on evidence-based practice, comparative effectiveness, and translational research, nursing scholarship is undergoing transformation. This article outlines guidelines for appointment and promotion that incorporate the academic tripartite and are relevant for all faculty. A clear and equitable pathway for professorial advancement for the both the clinician and research faculty is delineated. Without such clarity and equity, the unique contributions of clinical and research scholars and the synergy that results from these distinctions will not be garnered. Although there is significant overlap in the criteria, there are also distinguishing scholarly activities and outcomes. For each standard at each rank, unique sample criteria of clinical and research scholarship are outlined and the shared scholarly activities that demonstrate the standard. Using an adaptation of Boyer's model, the guidelines incorporate a broadened view of nursing scholarship and offer a framework for nursing academia that recognizes new ways of knowledge. Although recognizing the coexistence of science and practice, these guidelines offer a clear trajectory for advancement in the professorial role that applies an expanded perspective of and provide a framework for nursing scholarship.
EXTENSIONS OF OPERATOR ALGEBRAS I

Abstract We transcribe a portion of the theory of extensions of C ∗ -algebras to general operator algebras. We also include several new general facts about approximately unital ideals in operator algebras and the C ∗ -algebras which they generate.
Regional differences in the density and subtype specificity of endothelin receptors in rabbit urinary tract

We investigated the binding characteristics of endothelin (ET) receptors in rabbit ureter, bladder dome, bladder base, and urethra and compared the observed receptor properties with those of cloned human ETA and ETB receptors expressed in Chinese hamster ovary K-1 (CHO) cells. Receptor binding experiments with [125I]ET-1 revealed the presence of a single class of specific, saturable, high affinity [125I]ET-1 binding sites in all of the regions of the studied urinary tract. The rank order of the densities (Borax values) of [125I]ET-1 binding sites was: ureter ≫bladder dome > bladder base = urethra. ET-1 and ET-2 inhibited [125I]ET-1 binding to the membrane particulates from the various regions of the urinary tract with single high affinity constants. A selective ETA receptor antagonist, BQ 123, and selective ETB agonists, ET-3 and sarafotoxin S6c (STXc), inhibited [125I] ET-1 binding to bladder dome, bladder base, and urethra with high and low affinity constants indicating the presence of both ETA and ETB receptor subtypes in these tissues. The subtype specificity of ET receptors in the rabbit tissues is confirmed with inhibition data obtained from similar binding studies in cloned human ETA and ETB receptors. The proportions of high affinity binding sites for ET-3, representing ETB receptors, were approximately 25%, 27%, and 46% in bladder dome, bladder base, and urethra, respectively. Corresponding values for STXc were approximately 17%, 28%, and 43% in bladder dome, bladder base, and urethra, respectively. In contrast to the findings for ET-3 and STXc, the proportions of high affinity binding sites for BQ 123, representing ETA receptors, in bladder dome, bladder base, and urethra were approximately 84%, 74%, and 60%, respectively. In ureter, these selective compounds inhibited [125I]ET-1 binding with either a low (ET-3 and STXc) or a high binding affinity (BQ 123), suggesting the presence of only a single receptor subtype (ETA) in this tissue. These data indicate that there are regional differences in the density and subtype specificity of ET receptors in the rabbit urinary tract.
The Triumph and Failure of Albert Speer's Administrative Genius: Implications for Current Management Theory and Practice

In this article the authors explore Albert Speer's (Hitler's Minister of Armaments and War) theories of organizational change "with the specific purpose of framing and accentuating the anomaly that organizational change agents such as Albert Speer represent in technological societies. On the one hand, Speer was an exponent of some of the most advanced, participative, and 'humanistic'... management theories being endorsed today. At the same time, however, he utilized these theories and practices to promote the goals of one of the most inhumane societies in the history of mankind.. The crimes of the Third Reich are essentially modern crimes, made possible by 20th century technology, which holds within it both great promise and great danger for human values." The authors discuss the limitations of present forms of organizational change and suggest new directions and perspectives for an emerging theoretical base.
A Dimeric Mechanism for Contextual Target Recognition by MutY Glycosylase

MutY, an adenine glycosylase, initiates the critical repair of an adenine:8-oxo-guanine base pair in DNA arising from polymerase error at the oxidatively damaged guanine. Here we demonstrate for the first time, using presteady-state active site titrations, that MutY assembles into a dimer upon binding substrate DNA and that the dimer is the functionally active form of the enzyme. Additionally, we observed allosteric inhibition of glycosylase activity in the dimer by the concurrent binding of two lesion mispairs. Active site titration results were independently verified by gel mobility shift assays and quantitative DNA footprint titrations. A model is proposed for the potential functional role of the observed polysteric and allosteric regulation in recruiting and coordinating interactions with the methyl-directed mismatch repair system.
Changes in the fine structure of the parietal yolk sac of the rat placenta with increasing gestational age.

The fine structure of the portion of the parietal yolk sac which extends across the fetal surface of the rat placenta (which is the only portion of the parietal yolk sac which persists after the sixteenth day of pregnancy) was examined sequentially on the even numbered days during the second half of gestation. The placental parietal yolk sac was seen to consist of two cellular layers, trophoblast and endodermal epithelium, which were separated by a thick, amorphous membrane (of Reichert). The trophoblast attenuated with increasing gestational age and, on day 18, became perforated by fenestrations which were closed by diaphragmata. By day 22, the attenuated trophoblast was patently perforate, and maternal blood was exposed to Reichert's membrane. Since throughout gestation, the cells of the parietal endoderm formed a discontinuous layer, at all stages Reichert's membrane was exposed to the vitelline cavity. When ferritin and thorotrast were injected i.v., both separately and together, the former passed readily from maternal blood through Reichert's membrane and was phagocytosed by cells of the parietal endoderm. Thorotrast, however, did not cross Reichert's membrane. Since the rodent yolk-sac complex is known to serve as a placental route, selective permeability of Reichert's membrane may help regulate maternofetal exchange.
Tube vibration in a half-scale sector model of a helical tube steam generator

Abstract This paper presents the experimental technique and results of tests on a half-scale sector model of a steam generator helical coil tube bank. A series of tests was performed: (1) bench tests of a single helical tube in air; (2) tests of the sector model in air; (3) tests of the sector model in stationary water to determine natural frequencies and damping; (4) tests in flow. The experimental results reveal the general characteristics of the sector model and provide the information for the design evaluation of a helical tube array to avoid detrimental fluidelastic instability.
Comparative measurements of cochlear apparatus.

Micromeasurements of horizontal midmodiolar sections of temporal bones were performed to obtain the dimensions of the different cochlear partitions in the squirrel monkey, the cat, and the rat. The...