cssi/SciSciGPT-SciSciNet huggingface dataset:
Negative Effect of Item Heterogeneity on Split-Half Reliability Estimates: An Empirical Demonstration

ard psychometrically sound test so that both had the same mean value for all the interitem correlations yet they differed in terms of the variance among the interitem correlations. The two groups were then treated as separate tests, and all possible split-half correlations were computed for each "tesc." The more heterogeneous group resulted in a wider spread of split-half correlations. Furthermore, both groups of correlations showed a significant skew in the negative direcrion. It was concluded that an odd-even split and coefficient alpha significantly underestimate a test's true split-half reliability, as defined by the reliability coefficient generated by using the two most analogous forms of a test. It has been shown that, where items are extremely heterogeneous as in stimuli (e.g., cards) of many projective tests, exhaustive distributions of splithalf combinations for a given variable tend to be rectilinear (Wagner, Alexander, Roos, & Prospero, 1985; Wagner, Alexander, Roos, & Adair, 1986). In such cases, both an odd-even split and Cronbach's alpha (1951) can substantially underestimate the reliability of a test. The question arises as to whether even psychometrically sound tests might be vulnerable to the same weakness, i.e., a total range of split-half estimates too broad to justify settling for an average or an estimate of convenience such as an odd-even split. The rationale underlying split-half reliability is that the two halves of the test are analogous to two forms of a test which are equal in all possible respecrs. As such, the split-half reliability should theoretically be a maximized estimate. The only defensible rationale, aside from convenience, for computing a nonmaximized split-half, such as odd-even, is that the distribution of all possible split-half combinations is customarily so tightly packed, i.e., leptokurtic, that any random juxtaposition of two halves of a test would be just about as good as any other. It has often been tacitly assumed that most psychometric instruments, particularly those which measure a single factor such as "verbal ability," would produce similar split-half reliabilities regardless of how the test is split. But is this really the case, especially with heterogeneous items? The present study attempts to examine this question by selecting, from a well standardized psychometric test, two sets of items differing only in terms of heterogeneity and then using these items to generate respective distributions of all possible split-half combinations. While such an undertaking would be impossible for a test of normal length, say 75 items, it is quite feasible, with the aid of computerization, for smaller item subsets. It was hypothesized that
Polar and Nonpolar Interactions in Adhesion

Abstract Equations for polar and nonpolar interactions across the interface are developed by using energy additivity concept in a semi-continuum model. Interfacial and surface tensions of molten polymers are measured directly and used to test the resulting equations: The first expression may be called the harmonic-mean equation preferred for low energy systems such as organic liquids, water, polymers, and organic pigments. The second may be called the geometric-harmonic-mean equation preferred for high energy systems such as mercury, glass, metal oxides and graphite. The third may be called the geometric mean equation which is found unsatisfactory. The harmonic-mean equation is used to obtain the “optimum” wettability condition for adhesion. The importance of polar interactions and matching of the polarity are analyzed and emphasized.
Gandalf: an embodied humanoid capable of real-time multimodal dialogue with people

Gandalf is a fully autonomous, humanoid agent that perceives a user's multimodal actsNspeech, prosody, manual gesture, body language, gazeNand generates appropriate multimodal responses to these in real-time (speech, gaze, facial & manual gesture & head movement). Gandalf has knowledge about the solar system and can travel to and tell users about the planets and moons with speech and gesture. Gandalf demonstrates a coherent framework for psychosoical dialogue skills which enables the production of concurrent reactive and reflective behaviors and planning of communicative acts, with response cycles analogous to those found in human face-to-face dialogue, from 1/6th of a second and up. Gandalf has been tested in interaction with humans and shown to be capable of supporting and sustaining multimodal, situated, real-time dialogue. Content Areas: Interaction between people and agents, face-to-face communication, action selection and planning, real-time performance, synthetic agents.
Relations between demographic parameters

The mean life-expectancy describes the average prospective life-time of an individual aged zero. This parameter can be explicitly described in terms of the survivorship distribution of the population. The Malthusian parameter r represents the asymptotic growth rate of a population. This parameter can be implicitly expressed in terms of the net-maternity distribution. The parameters and r incompletely incorporate the age-specific fertility and mortality pattern of a population; distinct populations may have the same growth rate but different net-maternity functions; distinct populations may be characterized by the same mean life expectation but may have different survivorship distributions. This article analyzes a class of parameters called the entropy of a population (Demetrius, 1974a) which distinguishes between net-maternity functions with the same growth rate and also mortality distributions with the same mean life expectation. This class of parameters measures the convexity of the fertility and mortality distributions. This paper analyzes the relations between the entropy parameter and the standard demographic parameters.
Curriculum and Course Design: A New Approach Using Quality Function Deployment

In this article, the authors describe a method for assuring the quality of curriculum design based on techniques that have been used in industrial settings for over 30 years. Quality Function Deployment assures that the needs of the customer are considered at all levels of product design and a graphical matrix called the House of Quality serves as an aid in achieving its objectives. We provide an example showing how to apply these principles and techniques to business curriculum and course design in the academic domain of Management Information Systems. The resulting curricula will be more likely to address the needs of the employers of business school graduates and the resulting documentation will be valuable in guiding subsequent curriculum redesigns as the needs of business evolve.
Double-tip scanning tunneling microscope for surface analysis

We explore the possibility of using a double-tip scanning tunneling microscope to probe the single-electron Green function of a sample surface, and describe a few important applications: (1) probing constant energy surfaces in k space by ballistic transport; (2) measuring scattering phase shifts of defects; (3) observing the transition from ballistic to diffusive transport to localization; and (4) measuring inelastic mean free paths.
A Comparison of Several Bandwidth and Profile Reduction Algorithms

Abstract : This paper compares and analyzes six algorithms which have been suggested recently for use in reducing, by permutations, the bandwidth and profile of sparse matrices. This problem arises in many different areas of scientific computation such as in the finite element method for approximating solutions of partial differential equations and in analyzing large-scale power transmission systems.
The effects of expected inflation on real returns in the argentine indexed bond market

Abstract A relatively unrestricted market in goverment indexed bonds operated in the high-inflation Argentine economy from 1975 through 1982. The indexed bond yields from this period provide an interesting opportunity to examine the relation between real interest rates and expected inflation. The test results support the hypothesis that expected inflation is a significant source of variation in real interest rates, depressing the real yields on indexed bonds.
Myocardial contraction fraction: a volumetric index of myocardial shortening by freehand three-dimensional echocardiography.

Abstract Objectives This study sought to evaluate myocardial contraction fraction (MCF) as an index of myocardial shortening by comparison to conventional shortening indices in patients with hypertensive hypertrophy, athletes with physiologic hypertrophy and sedentary normal adult subjects. Background A significant percentage of patients with hypertensive hypertrophy have “normal” or “preserved” left ventricular (LV) systolic function by conventional echocardiographic measures whereas their systolic function is depressed when measured by the two-dimensional echocardiographic mid-wall shortening fraction (MWSF). A three-dimensional echocardiographic measure of myocardial shortening analogous to MWSF has been lacking. We describe a volumetric measure of myocardial shortening, the MCF, as the ratio of stroke volume (SV) to myocardial volume (MV), and hypothesize that it may be useful to compare myocardial performance in patients with different degrees and types of hypertrophy. Methods We compared the MCF using freehand three-dimensional echocardiographic reconstruction of the LV to conventional measures of LV function (ejection fraction [EF], endocardial shortening fraction [SF] and MWSF) in subjects with pathologic hypertensive hypertrophy, heart failure symptoms and preserved EF (n = 17), athletes with physiologic hypertrophy (n = 41) and normal sedentary adults (n = 80). Results The EF was in the normal range for all three groups. The MCF was lower in hypertensive hypertrophy compared with normal subjects (0.33 ± 0.05 vs. 0.44 ± 0.07, p Conclusions The MCF, a volumetric measure of myocardial shortening, demonstrates that myocardial shortening is decreased in hypertensive hypertrophy and increased in physiologic hypertrophy. The MCF may be useful in assessing differences in myocardial performance in patients with similar degrees of hypertrophy.
Ultrastructure of the Ovary of the Hagfish Eptatretus stouti

Ultrastructure of the ovary of the Pacific hagfish was studied. Attention was paid to the mesovarium, small oocytes, oocytes of intermediate size, large oocytes, postovulatory follicles shortly after ovulation, postovulatory follicles considerably after ovulation, and preovulatory atretic follicles. The progressive changes of thecal and granulosa layers in the course of egg development and degeneration are described. No cells showing the ultrastructural characteristics associated with steroidogenesis were found.
Expanding the biocultural synthesis toward a biology of poverty

Les AA. presentent et discutent brievement la demarche des contributions a ce numero dont l'objectif est d'explorer les nouvelles approches bioculturelles qui integrent l'analyse sociale, economique, et politique en biologie humaine, et qui centrent l'analyse sur les consequences biologiques de la pauvrete et des inegalites. Les articles presentes sont issus de deux symposiums tenus en 1994 par l'American Association of Physical Anthropologists et l'American Anthropological Association dont les intitules etaient respectivement : Perspectives sociales et d'economie politique en anthropologie biologique, et La biologie de la pauvrete. Les AA. soutiennent notamment que l'anthropologie biologique occupe une position particuliere dans le champ de l'anthropologie. L'integration des perspectives socioeconomiques et politiques de l'anthropologie sociale et culturelle aux perspectives sur l'ecologie et les processus d'adaptation de l'anthropologie biologique, met en evidence que la biologie humaine est affectee, au moins a court terme, par le controle, la production, et la repartition des ressources materielles, l'ideologie, et le pouvoir.
Fixation of deleterious alleles, evolution and human aging

Human aging, like everything else in biology, only makes sense in the context of evolution. There is substantial agreement among evolutionary geneticists regarding the evolutionary underpinnings of one of the main questions of human aging i.e. 'Why do we age?', which involves the higher rate of fixation of alleles that cause deleterious post-reproductive phenotypes vs. alleles that cause deleterious pre-reproductive phenotypes. Even higher rates of fixation of deleterious mutations are predicted to occur on population genetic grounds in two non-recombinant genomes in humans i.e. the Y chromosome, and the mitochondrial genome. The added burden of deleterious mutations on the Y may explain the reduced average lifespan of males vs. females. A high predicted fixation rate of the mitochondrial genome may explain its fast rate of evolution, and the high frequency of mitochondrial disease in relationship to this genomes' small size, and may underlie the transfer of mitochondrial genes over evolutionary time to the nucleus. Thus a molecular evolutionary model of aging which focuses on increased fixation rates of (1) nuclear alleles which only have deleterious effects post-reproduction, (2) deleterious genes on the Y chromosome, and (3) deleterious genes on the mitochondrial genome, makes multiple testable predictions about the causes and mechanisms of aging.
Spectroscopic constraints on the properties of dust in active galactic nuclei

The optical properties of graphite, silicate, and SiC grains over the wavelength range 1000 microns - 1 A are calculated for grains in the 0.005-10-micron size range. Both graphite + silicate (MRN) and graphite + SiC grain mixtures are considered, with various grain size distributions. A detailed radiative transfer calculation is performed to obtain constraints on the emission properties of dust in AGN in either 'optically thin' or optically thick configurations. Warm graphite + silicate or graphite + SiC dust (T is greater than 200 K) with the MRN size distribution and a column density less than about 10 exp 23/sq cm produces a strong silicate or SiC emission feature. Such dust cannot be responsible for the observed IR emission from AGN. MRN dust with a high optical depth at 10 microns produces an emission feature with an amplitude of about 57 percent, in excess of the typical observational limit for most objects. Reddening of the broad emission lines and continuum is unlikely to be common.
The characterization of a proposed model GaAs/anodic oxide interface

The n-GaAs/anodic oxide interface has been characterized using capacitance-voltage (C-V) measurements on MOS capacitors and current-voltage (I-V) measurements on Schottky barriers. A simple interface state model cannot explain the observed behavior. Schottky barrier measurements made on surfaces which were previously anodized with the oxide layer subsequently removed by etching show evidence for the presence of a compensated layer in the anodized semiconductor surface region. This leads to a maximum in the conduction band energy near the surface, and based on these observations a quantitative model is formulated which can partially explain some aspects of the GaAs/anodic oxide interface, including the accumulation mode capacitance dispersion observed by many authors. Further studies were made in which the oxides were grown to difference thickness and then etched to the same thickness. Measurements on these oxides show that the C-V dispersion is related to the current density during growth and to the thickness of the oxide. There is also a correlation between the temperature during oxide growth and the interface properties. Oxides grown at 65°C show significantly more dispersion than oxides grown at 0°C. The temperature during anodization is also found to influence the anodization constant.
CA125/MUC16 Is Dispensable for Mouse Development and Reproduction

Cancer antigen 125 (CA125) is a blood biomarker that is routinely used to monitor the progression of human epithelial ovarian cancer (EOC) and is encoded by MUC16, a member of the mucin gene family. The biological function of CA125/MUC16 and its potential role in EOC are poorly understood. Here we report the targeted disruption of the of the Muc16 gene in the mouse. To generate Muc16 knockout mice, 6.0 kb was deleted that included the majority of exon 3 and a portion of intron 3 and replaced with a lacZ reporter cassette. Loss of Muc16 protein expression suggests that Muc16 homozygous mutant mice are null mutants. Muc16 homozygous mutant mice are viable, fertile, and develop normally. Histological analysis shows that Muc16 homozygous mutant tissues are normal. By the age of 1 year, Muc16 homozygous mutant mice appear normal. Downregulation of transcripts from another mucin gene (Muc1) was detected in the Muc16 homozygous mutant uterus. Lack of any prominent abnormal phenotype in these Muc16 knockout mice suggests that CA125/MUC16 is not required for normal development or reproduction. These knockout mice provide a unique platform for future studies to identify the role of CA125/MUC16 in organ homeostasis and ovarian cancer.
Can allosteric regulation be predicted from structure

During the last decade, the classical view of a protein existing in equilibrium between discrete conformational states has undergone a radical transformation. Experimental observations, particularly those obtained from NMR-detected hydrogen/deuterium exchange, indicate that even under native conditions proteins need to be considered as complex statistical ensembles (see for example refs. 1–13). In the view pioneered by Englander and coworkers (1, 2, 4, 7, 8, 14) proteins undergo local unfolding reactions scattered throughout their entire structures. These unfolding reactions occur independently of each other, may involve only a few amino acids, and give rise to a large number of states in which each state is defined by the presence of one or several locally unfolded regions. This collection of states defines the native-state ensemble. The immediate, and perhaps most relevant, consequence of these observations is that the Gibbs energy of stabilization of a protein is not uniformly distributed throughout its three-dimensional structure. There are regions with high stability constants and regions with low stability constants (13, 15). Furthermore, under native conditions cooperativity appears to be local or regional rather than global. The implications of these findings have been mostly discussed in relation to the protein folding problem; however, their biological implications are tremendous because the native state is the functionally relevant state. If cooperativity is local or regional rather than global, how do distal sites communicate with each other? How do regulatory allosteric interactions take place? How are the functional properties of a protein related to the distribution of states within the native ensemble, and how does ligand binding affect this distribution and modulate function? Is the location of stable and unstable regions a random event or it is dictated by functional considerations? How are protein function and stability related?
STABILITY OF FAMOTIDINE IN POLYPROPYLENE SYRINGES USING A STABILITY-INDICATING HPLC ASSAY

Famotidine syringes (2 mg/mL) were prepared under sterile conditions in accordance with United States Pharmacopeia (USP). To test the stability, syringes were kept for 30 d under three different temperature conditions: room temperature (22–25°C), refrigerated (2–6°C), and frozen (−20°C). Three samples from each temperature were withdrawn and were assessed for stability on days 0, 7, 15, 22, and 30 as per the USP guidelines. Physical stability was assessed by visual examination and pH values. The assay of famotidine was examined by a stability-indicating HPLC method and a significant loss of stability was defined as 10% or greater decrease in famotidine content over time. Physical stability results illustrated that no precipitation, cloudiness, or color change was observed in famotidine syringes at all the temperatures studied. Results from the assay content by HPLC showed that famotidine injections retain greater than 90% of the initial concentrations for 30 d when stored at room temperature and frozen; a...
Relative Contributions of the Atrial Systole-Ventricular Systole Interval and of Patterns of Ventricular Activation to Ventricular Function during Electrical Pacing of the Dog Heart

In areflexic canine right heart bypass preparations, little difference in ventricular function was observed as a result of atrial pacing, sequential atrioventricular pacing, or atrial-His bundle pacing at an appropriate atrial systole-ventricular systole (As-Vs) interval. Ventricular function was depressed during ventricular pacing and during atrioventricular pacing with an inappropriate As-Vs interval. In areflexic isovolumic left ventricle preparations, ventricular function was depressed during ventricular pacing compared to atrial pacing, and changes in the As-Vs interval during atrioventricular pacing were accompanied by changes in ventricular function only in association with changing patterns of ventricular activation. In animals with heart block under conditions of right heart bypass, wherein changes in the pattern of ventricular activation were precluded during atrioventricular pacing, ventricular function deteriorated pari passu with shortening of the As-Vs interval. These data indicate that both the temporal relation between atrial and ventricular contraction and the pattern of ventricular activation importantly influence ventricular function during cardiac pacing. The marked changes in ventricular function observed as a function of the As-Vs interval, for any given pattern of electrical activation, suggest that the As-Vs interval is the more important determinant of ventricular function during cardiac pacing.
Social novelty enhances brain cell proliferation, cell survival, and chirp production in an electric fish, Apteronotus leptorhynchus

For many animals, enriched environments and social interaction promote adult neurogenesis. However, in some cases, the effect is transient, and long-term environmental stimuli have little benefit for neurogenesis. In electric fish, Apteronotus leptorhynchus, fish housed in pairs for 7 days show higher density of newborn brain cells (cell addition) than isolated fish, but fish paired for 14 days have rates of cell addition similar to isolated controls. We examined whether introduction of social novelty can sustain elevated levels of cell addition and prevent long-term habituation to social interaction. We also monitored electrocommunication signals (“chirps”) as a measure of the behavioral response to social novelty. We paired fish for 14 days with one continuous partner (no social novelty), two sequential partners changed after 7 days (low novelty) or seven sequential partners changed every 2 days (high novelty). On Day 11, we injected fish with BrdU, sacrificed fish 3 days later and quantified BrdU labeling in the diencephalic periventricular zone. Fish exposed to no novelty had BrdU labeling similar to isolated fish. Fish with low novelty showed small increases in BrdU labeling and those with high novelty had much greater BrdU labeling. Similarly, chirp rates were greater in fish with low novelty than with no novelty and greatest yet in fish with high novelty. By varying the timing of novelty relative to BrdU injection, we showed that social novelty promoted both proliferation and survival of newborn cells. These results indicated that brain cell proliferation and survival is influenced more by social change than simply the presence of social stimuli. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2013
Imaging as-grown single-walled carbon nanotubes originated from isolated catalytic nanoparticles

Discrete catalytic nanoparticles with diameters in the range of 1–3 nm are obtained by placing controllable numbers of metal atoms into the cores of apoferritin. With nanoparticles placed on transmission electron microscope (TEM) grids coated with ultra-thin alumina membranes, isolated single-walled carbon nanotubes are grown by chemical vapor deposition and directly examined by TEM. The characterizations, carried out at single-tube and single-particle level, obtain clear evidence that the diameters of the nanotubes are determined by the diameters of catalytic nanoparticles. For the first time, both ends of an as-grown single-walled nanotube are imaged by TEM, leading to a microscopic picture of the nanotube-growth mechanism.
Concentrations and vertical fluxes of zooplankton fecal pellets on a continental shelf

The contribution of fecal pellets to the benthos of the southeastern shelf of the USA is investigated through an analytic model which considers pellet production by different stage groups of the genus Paracalanus. Model results indicate that the concentration and vertical flux of pellets is a function of producer size and consumer size and abundance. Nauplii and adults, respectively, produce daily on the average 50 and 13% of total pellet mass, yet contribute 4 and 63%, respectively, to the daily pellet flux. Most of the pellets produced are consumed or degraded in the water column, with only 0.2% of the average daily primary production reaching the seafloor (35 m) as fecal pellets. This contributes to an impoverished benthos, such as that found on the southeastern continental shelf.
OSCILLATING FLOW PAST A RIGID CIRCULAR CYLINDER: A FINITE-DIFFERENCE CALCULATION

A finite-difference study of the sinusoidally oscillating flow past a fixed circular cylinder is made using vorticity and stream function as the dependent variables. Calculations are performed for conditions which lead to both a symmetric wake and an unsymmetric wake. The Reynolds number ranges from 100 to 3000 and the Keulegan-Carpenter number ranges from 1 to 12. A hybrid differencing scheme is introduced to provide a stable for large values of the parameters. Good comparison to flow visualisation results and calculated force coefficients is found. The results are given a physical interpretation for the various vortex patterns observed.
Making the Mundane Sacred Through Technology: Mediating Identity, Ecology and Commodity Fetishism

This article explores the sanctifying power of technology and digital imagery, and its use for local political action. Drawing on fieldwork undertaken in northeastern Thailand, the author examines how a photograph of a tree and its presentation on a laptop computer were used to save the tree from being cut down. He shows how a unique combination of rhetorical strategy and commodity fetishism, when coupled with the digital image, rendered the tree sacred and therefore untouchable; this was possible due to the cultural identity of rural villagers, who imagine themselves simultaneously as both rural and national.
A suite of computer-based tools for teaching mechanics of materials

In this article we describe an integrated suite of multimedia and simulation software developed to support the teaching of mechanics of materials. The materials are designed to support both classroom presentation and student-directed learning, provide direct manipulation and visualization, and foster exploration and experimentation. © 1996 John Wiley & Sons, Inc.
Optochemical dissection of T-box gene-dependent medial floor plate development.

In addition to their cell-autonomous roles in mesoderm development, the zebrafish T-box transcription factors no tail a (ntla) and spadetail (spt/tbx16) are required for medial floor plate (MFP) formation. Posterior MFP cells are completely absent in zebrafish embryos lacking both Ntla and Spt function, and genetic mosaic analyses have shown that the two T-box genes promote MFP development in a non-cell-autonomous manner. On the basis of these observations, it has been proposed that Ntla/Spt-dependent mesoderm-derived signals are required for the induction of posterior but not anterior MFP cells. To investigate the mechanisms by which Ntla and Spt regulate MFP development, we have used photoactivatable caged morpholinos (cMOs) to silence these T-box genes with spatiotemporal control. We find that posterior MFP formation requires Ntla or Spt activity during early gastrulation, specifically in lateral margin-derived cells that converge toward the midline during epiboly and somitogenesis. Nodal signaling-dep...
Ada tasking and parallel processors

This paper describes the creation of a shared memory multiprocessor runtime that uses the Ada language tasking model as the basis for CPU allocation. The modifications to an Ada runtime targeted to a single MIL-STD-1750A processor to create a multiprocessor Ada runtime are described. Some performance information is given.
DNA-sequence specificity of mutations at the human thymidine kinase locus.

Abstract We have established a system for the study of DNA-sequence specificity at a functionally heterozygous thymidine kinase ( tk ) locus in a human lymphoblastoid cell line (TK6). Characterization of the parental locus demonstrated that the 2 tk alleles were fortuitously distinguished by differential gene expression. One round of PCR amplification yielded a specific tk cDNA product only for the functional parental allele. Analysis of cDNA from newly mutated alleles which retain substantial levels of expression is thus simplified. Amplification and sequencing of tk genomic sequences was used for analysis of low expression mutants, and in order to distinguish and characterize deletion and splicing mutations. DNA-sequence analysis of the parental locus identified a frameshift in tk exon 4 of the non-functional parental allele, and surprisingly, an exon 7 frameshift mutation in the functional tk allele. This exon 7 frameshift results in a predicted alteration of the final 21 amino acids of the TK protein, and a C-terminal extension of 131 additional amino acids. Since TK6 is phenotypically TK + , we can infer that this major C-terminal modification does not eliminate enzymatic activity. The system was utilized for the analysis of 36 spontaneous TK − mutants. Loss of heterozygosity accounted for 58% of the mutations, 11% were attributable to intragenic deletions, and the remainder involved point mutations, primarily G:C to A:T transitions.
Hematological response of hemorrhaged Japanese quail after blood volume replacement with saline.

Abstract 1. 1. Hematological responses to hemorrhage by phlebotomy with and without replacement of blood volume with saline were measured in juvenile and adult male Coturnix coturnix japonica . 2. 2. Recovery of total peripheral erythrocyte numbers and total peripheral leukocyte numbers occurred within 72 hr postphlebotomy in both treatment groups. 3. 3. Saline replacement of blood volume following hemorrhage increased the total numbers and differential percentages of circulating reticulocytes at 72 hr postphlebotomy above the reticulocyte values of phlebotomized quail receiving no saline in both adult and juvenile Japanese quail.
The Association of Race/Ethnicity with Objectively Measured Sleep Characteristics in Older Men

This study examined the association between race/ethnicity and objectively measured sleep characteristics in a large sample of older men. Black men had significantly shorter total sleep time (6.1 hr vs. 6.4 hr), longer sleep latency (28.7 min vs. 21.9 min), lower sleep efficiency (80.6% vs. 83.4%), and less slow-wave sleep (4.9% vs. 8.8%) than White men, even after controlling for social status, comorbidities, body mass index, and sleep-disordered breathing. Hispanic men slept longer (6.7 hr) at night than Black (6.1 hr) and Asian American men (6.1 hr). This study supports significant variations in sleep characteristics in older men by race/ethnicity.
Studies on the synthesis of (+/-)-stenine: a combined intramolecular [4 + 2]-cycloaddition/rearrangement cascade.

Several cyclic 2-(methylthio)-5-amidofurans containing tethered unsaturation were prepared via the reaction of dimethyl(methylthio)sulfonium tetrafluoroborate (DMSTF) with β-alkoxy-γ-dithiane lactams. Thermolysis of these furans resulted in an intramolecular Diels−Alder reaction (IMDAF). The resulting oxa-bridge cycloadducts underwent a subsequent 1,2-methylthio shift to form tricyclic lactams in high yield. Furan 9, annealed to an azepine ring, underwent the IMDAF reaction at or below room temperature. Conformational effects imposed by the placement of a carbonyl group within the tether, combined with a rotational bias about the C(2)−N bond, enhances the rate of the IMDAF reaction of the seven-ring system so that it occurs readily at 25 °C. The feasibility of using the cascade sequence in the context of a total synthesis of the Stemona alkaloid (±)-stenine was explored. The eventual synthesis of (±)-stenine was carried out by an intramolecular Diels−Alder reaction of a 2-amido-5-methylthio-substituted fu...
Protein-protein diffusional encounter

Protein-protein association is clearly a very important process in biology, including events such as signal transduction, immune response, and transcription. Protein-protein association rates are in the range of 103 to 109 M-l S-1, with those in the diffusion-limited regime having rates of .106 M-1 s. One well-characterized protein-protein system, barnase-barstar, associates at a rate of _ 108 M-1 sl, falling well into the diffusion-limited regime (Schreiber and Fersht, 1996, and references therein). There are other factors that help to identify a system as being diffusion limited, which are that the association rates are influenced by solvent viscosity, ionic strength, temperature, and diffusional environment. The barnasebarstar system has such a high rate of association because of the contribution of electrostatics (Schreiber and Fersht, 1996). Wild-type barnase has a net charge, at pH 8, of +2, and that of barstar is -6. In this issue, Gabdoulline and Wade (1997) describe the application of their effective charge method (Gabdoulline and Wade, 1996) in a simulation of the diffusional encounter of barnase and barstar. Protein-protein association still represents a significant challenge for computational chemistry, even though substantial advances have been made in the development of theory for these problems. Molecular dynamics methods are generally too time consuming and demanding, especially if explicit solvent is included. Most computational work on protein-protein as-
Jonathan Barry, Witchcraft and demonology in South-West England, 1640-1789

The voices of the poor and the dispossessed are rarely listened to in any age. They are too rough, too uncomfortable, and too discordant to sit comfortably within the confines of learned discourse,...
Optical potential for 12C + 28Si scattering

Abstract 12 C + 28 Si elastic scattering angular distributions are smooth functions, relatively easily fit by optical potential predictions, at laboratory bombarding energies, E 1 ab , within ≈ 10 MeV of the Coulomb barrier (i.e. up to E 1 ab ≈ 27 MeV). Between E 1 ab = 27 and 36 MeV the angular distributions show pronounced oscillatory structure which is not easily fit with an optical potential. No optical potential has been found to give a very good account of all the angular distributions simultaneously; the best simultaneous fit to all the data was achieved with a surface-transparent potential whose real and imaginary well depths are energy dependent.
Patterns of Statewide Test Participation for Students With Significant Cognitive Disabilities

Students with significant cognitive disabilities are eligible to participate in two statewide testing options for accountability: alternate assessments or general assessments with appropriate accommodations. Participation guidelines are generally quite vague, leading to students “switching” test participation between years. In this study, we tracked test participation for two cohorts of students with a documented disability over 3 years. Results suggested approximately 25% of students who initially took the alternate assessment switched test type at least once, although patterns of switching were not consistent across disabilities. Students on the performance “bubble” were more likely to switch test participation. Test switching poses challenges for monitoring students’ academic growth within accountability frameworks.
Supervised Bayesian latent class models for high-dimensional data

High-grade gliomas are the most common primary brain tumors in adults and are typically diagnosed using histopathology. However, these diagnostic categories are highly heterogeneous and do not always correlate well with survival. In an attempt to refine these diagnoses, we make several immunohistochemical measurements of YKL-40, a gene previously shown to be differentially expressed between diagnostic groups. We propose two latent class models for classification and variable selection in the presence of high-dimensional binary data, fit by using Bayesian Markov chain Monte Carlo techniques. Penalization and model selection are incorporated in this setting via prior distributions on the unknown parameters. The methods provide valid parameter estimates under conditions in which standard supervised latent class models do not, and outperform two-stage approaches to variable selection and parameter estimation in a variety of settings. We study the properties of these methods in simulations, and apply these methodologies to the glioma study for which identifiable three-class parameter estimates cannot be obtained without penalization. With penalization, the resulting latent classes correlate well with clinical tumor grade and offer additional information on survival prognosis that is not captured by clinical diagnosis alone. The inclusion of YKL-40 features also increases the precision of survival estimates. Fitting models with and without YKL-40 highlights a subgroup of patients who have glioblastoma (GBM) diagnosis but appear to have better prognosis than the typical GBM patient.
ULTRASONIC IMAGING VELOCIMETRY OF TRANSIENT LIQUEFACTION OF COHESIONLESS PARTICULATE MEDIA

Abstract The loss of shear strength of a water-saturated cohesionless particle bed, known as liquefaction, was imaged in real time using clinical ultrasound back-scattering in an effort to distinguish liquefied from settled states in transient events. In the ultrasonic movies, the liquefied regions were found to be readily identifiable by their characteristic small-scale random fluctuations, which are consistent with the known phenomenon of particle diffusion in suspensions. The time sequences were analyzed and found to display an upward propagating interface separating settled from suspended regions, similar to the kinematic waves that arise in batch sedimentation, although their speeds were measured to be up to an order of magnitude greater than the terminal velocity of an isolated particle. On the basis of this similarity, the solidification process that follows liquefaction was modeled using drift flux theory and the Richardson-Zaki correlation, which was found to give a good match with the high measured solidification wave speeds.
Spectroelectrochemistry of tetracyanoquinodimethane modified electrodes

Abstract Thin films of a tetracyanoquinodimethane (TCNQ) oligomer adsorbed on optically transparent platinum electrodes have been studied using spectroelectrochemical techniques. In contact with aqueous electrolytes the electron aceptor sites in these modified electrodes are reduced to mixtures of the radical aion, TCNQ ⨪ , the dimer radical anion, TCNQ 2− 2 , the dimer dianion, TCNQ 2 2− , and the dianion, TCNQ 2∮ . Electrolyte effects on the reduction process and the stability of the reduced films were studied. Both monovalent and divalent ions exhibited Nernstian potential dependence, and in the presence of Ca 2+ ions the dianion state was stabilized. Counterion effects are suggested as the origin of variations in the wave shape in multcycle voltammograms.
Picosecond laser studies of anomalous ultrasonic sound damping in optical filter glasses

We used picosecond degenerate four-wave mixing technique to study acoustic properties of the laser induced ultrasonic sound wave in optical filter glasses. Ultrasonic velocity and absorption were measured over the frequency range of (100 MHz -20 GHz) we found the frequency dependence of the acoustic absorption in these filter glass are in quantitative disagreement with the prediction of the two-level system relaxation model. In additional to sound velocity and absorption coefficients various of photoelastic and thermal optical constants of the optical glass materials can be determined accurately by this method.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Measurements in turbulent liquid flow through a vertical concentric annular channel

Mesure du champ des vitesses dans un ecoulement turbulent de liquide dans un espace annulaire vertical non chauffe. Mesure du champ des temperatures et du profil des vitesses moyennes dans l'ecoulement d'un liquide dans le meme espace annulaire dont la paroi interne est chauffee et la paroi externe est isolee
A study of bentonite flocculation test for measurement of type-specific streptococcal antibodies.

SummaryA flocculation test for detection and measurement of type-specific antibody to Group A streptococci has been evaluated. A single strain of each of 3 serological types of streptococcus was employed. When a suspension of bentonite particles between 1.0 and 1.5 μ in size was exposed to an unad-sorbed homologous rabbit antiserum after being coated with partially purified M protein antigen, flocculation was obtained. The highest homologous flocculation titer encountered was 1-32. A weak non-reciprocal cross-reaction between types 36 and 14 M antigens was found: while M antigen of strain S-94 (type 36) did not react with anti-S-23 (type 14) antisera, M protein of strain S-23 exhibited some cross-reactivity with anti-S-94 antisera. The test antigen could be stored at 4°C for at least 6 weeks without loss of potency. No group-specific or type-specific flocculation occurred when the test antigen was prepared by exposing the bentonite particles to a crude antigen mixture, obtained by hot HCl extraction of st...
3s--3p, 3p--3d, and 3d--4f transitions of sodiumlike ions

New measurements have been made for wavelengths of the 3s–3p, 3p–3d, and 3d–4f transitions of the sodiumlike ions Cu18+, Zn19+, Ga20+, Ge21+, As22+, Se23+, Br24+, Kr25+, Y28+, Zr29+, Nb30+, Mo31+, Ru33+, Rh34+, Pd35+, Ag36+, and Sn39+. The measurements were made by photographing laser-produced plasmas and tokamak plasmas with grazing-incidence spectrographs. The energies of the transitions were also calculated with Dirac–Fock computer codes. By fitting the differences between the observed and calculated wave numbers to simple formulas, least-squares-fitted wavelengths for all sodiumlike ions from Ar7+ to Xe43+ were determined. The estimated uncertainty of the fitted wavelengths is ±0.007 A, which makes them useful as reference values. The wavelengths range from 9 to 713 A.
THE EFFECTIVENESS OF EDUCATING PEDESTRIANS ABOUT THEIR OWN NIGHTTIME VISIBILITY

Pedestrians consistently overestimate their visibility at night. This paper examines the effectiveness of several strategies of educating pedestrians about their own nighttime visibility. 48 participants were assigned to one of four groups: lecture, demo, combo, or control. Prior to data collection, participants in the lecture and combo groups heard a lecture on applied visual physiology. Immediately before data collection, participants in the demo and combo groups sat in a car and watched nighttime pedestrian visibility demonstration. Under various clothing and illumination configurations, all participants walked towards a stationary car until they believed they were recognizable as a pedestrian. The lecture significantly reduced estimated visibility distances. This result is encouraging since it suggests public education efforts may be useful. The demonstration did not produce significant changes when participants wore either white or black clothing, but significantly increased estimates when wearing retroreflective strips.
RFID-based localization system for mobile robot with Markov Chain Monte Carlo

This paper proposes a robust and precise localization system for mobile robots with the aid of Radio Frequency Identification (RFID) technology and the Markov Chain Monte Carlo (MCMC) optimization algorithm. By integrating the RFID module, RFID tags, a mobile robot and an off-board computer together, the localization system uses MCMC to analyze RFID signal information and get optimized mobile robot's location information. This paper focuses on explaining the development of RFID sensor model and the processes of building the MCMC algorithm. For sensor model development, the effects of orientation between the RFID reader and RFID tag and the velocity of the mobile robot are investigated. For the MCMC method, a sequential Monte Carlo method is adopted to optimize the result. Finally, the initial experiment results indicate that the proposed localization system has low error and could be used to effectively locate mobile robots.
Effect of chronic cardiac denervation on arrhythmias after coronary artery ligation.

Extrinsic cardiac denervation protects animals from fatal arrhythmias after coronary artery ligation and no change in heart rate or blood pressure is noted. Adequate time must elapse after surgical denervation for myocardial catecholamine depletion or arrhythmias will occur. Reserpine pre-treatment plus cervical vagotomy reduces the incidence of ventricular fibrillation. The relationship between myocardial catecholamines and arrhythmias is discussed.
Improving maintenance of physical activity in older, knee osteoarthritis patients trial-pilot (IMPACT-P): Design and methods

Abstract Promoting increased physical activity participation is now consistently advocated in the medical management of knee osteoarthritis (OA). Unfortunately, physical activity interventions targeting older knee OA patients are plagued by high attrition rates and poor long-term adherence. Consequently, identifying effective approaches for promoting maintenance of physical activity participation is integral for the successful behavioral management of knee OA. The present study, the Improving Maintenance of Physical Activity in Knee Osteoarthritis Pilot Trial (IMPACT-P), was a single-blind two-arm, randomized controlled pilot study designed to contrast the effects of a group-mediated cognitive behavioral (GMCB) exercise intervention with those of traditional center-based exercise therapy approach (TRAD) in older, knee OA patients. A total of 80 older adults with symptomatic knee OA were randomly assigned to GMCB or TRAD interventions. The primary outcome of the IMPACT-P study was changed in self-reported (CHAMPS questionnaire) and objectively assessed (LIFECORDER EX Plus) physical activity participation of moderate intensity or greater. Secondary outcomes include physical function, quality of life, and social cognitive variables. Outcomes were obtained at baseline, 3 month, and 12 month assessments by trial personnel blinded to participants' randomization assignment. Discussion. Determining the comparable efficacy of the GMCB and TRAD exercise interventions in producing meaningful improvements in physical activity and OA outcomes could enhance the efficacy of implementing physical activity participation in the behavioral management of symptomatic knee OA.