cssi/SciSciGPT-SciSciNet huggingface dataset:
Grain and grain boundary effects on the frequency and temperature dependent dielectric properties of cobalt ferrite–hafnium composites

Abstract We report on the frequency (f=20 Hz–1 MHz) and temperature (T=300–973 K) dependent dielectric properties of hafnium (Hf) incorporated cobalt ferrite (CoF2−xHfxO4 (CFO–Hf); x=0.00–0.20). The dielectric constant (e') of CFO–Hf is T-independent at T 450 K) variation. Correspondingly, electrical responses in impedance formalism are attributed to the grain and grain-boundary effects which also accounts for the observed two dielectric-relaxations. The results demonstrate that the dielectric phenomena in CFO–Hf can be tailored by tuning Hf-concentration.
The effect of enzymatically degradable IPN coatings on peri-implant bone formation and implant fixation.

Short-term osseointegration of orthopedic implants is critical for the long-term stability of the implant–bone interface. To improve initial implant stability, one strategy under consideration involves the presentation of adhesion ligands on the implant surface to stimulate bone regeneration in the peri-implant region. To assess the relative effects of implant surface chemistry and topography on osseointegration within the rat femoral ablation implant model, a nonfouling, enzymatically degradable interpenetrating polymer network (edIPN) of poly(AAm-co-EG/AAc) amenable to presenting the cell signaling domain Arg-Gly-Asp (RGD), was developed. Moderate enhancement of peri-implant bone formation was found after 28 days using the edIPN without peptide modification (p = 0.032). However, no data supported a benefit of peptide modification, as bone–implant contact, normalized bone volume and normalized fixation strength was equivalent or poorer than dual acid-etched (DAE) treated implants after 28 days. Surface topography was determined to be the dominant factor in modulating osseointegration, as DAE implants produced equivalent roughness-normalized fixation strength versus previously reported data on plasma-sprayed hydroxyapatite/tricalcium phosphate-coated implants (Barber et al., J Biomed Mater Res A, forthcoming). An ideal osseointegrated implant will require optimization of all three aforementioned parameters, and may take the form of biomolecule delivery from thin degradable polymer networks. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Structures of ascaroside aglycones.

Abstract Free and derivatized aglycones and parent ascarosides of Ascaris lumbricoides and A. columnaris (Nematoda) were isolated by thin-layer and gas chromatography and analyzed by mass spectrometry and polarimetry. Results for monol aglycones confirmed previous chain-length assignments and the location of the l -hydroxyl group at C-2. The major monols of even carbon number possessed a methyl branch on the penultimate carbon (ω − 1). Diol alycones were entirely unbranched homologues, mainly 31 and 33 carbons long, and had hydroxyl groups on C-2 and C-(ω − 1). These aglycones were truly symmetrical, for they were optically inactive with the center bearing the glycone in diol ascaroside (C-2), being mostly or entirely the l configuration. Three major features of ascaroside structure—chain length composition of the aglycones, molecular weight of the unusual glycone (a dideoxyhexose), the kind and position of acyl groups—were clearly discernible in the spectra of intact ascarosides.
Motion and color processing in school‐age children and adults: an ERP study

Stimuli designed to selectively elicit motion or color processing were used in a developmental event-related potential study with adults and children aged 6, 7 and 8. A positivity at posterior site INZ (P-INZ) was greater to motion stimuli only in adults. The P1 and N1 were larger to color stimuli in both adults and children, but earlier to motion stimuli only in adults. Finally, the P2 was larger to color stimuli in adults but larger to motion stimuli in children, and earlier to motion stimuli only in children. The findings across components indicate development from middle childhood to adulthood in aspects of both the motion and color processing systems indexed by this paradigm, but are consistent with an hypothesis of a more protracted time course of development for the motion as compared to the color processing system.
Correlation Functions as Hydrodynamic Green's Functions

A formal solution for the thermodynamic variables describing a system in a nonequilibrium state is given in terms of space- and time-dependent correlation functions. The solution during the hydrodynamic stage is also given by the Green's function solution to the hydrodynamic equations. The correlation functions contain information, not contained in the Green's functions, about the initial relaxation of the system to the hydrodynamic stage. Comparison of the two solutions shows that the correlation functions are the propagators for the physically specified initial data, while the Green's functions are the propagators for a different set of initial data. General connective equations are obtained for the two sets of data by comparing the Green's function solution to the correlation function solution. Initial conditions for the hydrodynamic equations are not, in general, equal to the physical initial conditions because of the short initial "ageing" period during which the differential equations do not apply.
I-Cell disease: isoelectric focusing, concanavalin A-Sepharose 4B binding and kinetic properties of human liver acid beta-D-galactosidases.

Isoelectric focusing of the acid beta-D-galactosidases (beta-D-galactoside galactohydrolase, EC 3.2.1.23) in normal crude liver supernatant fluids demonstrated multiple isoelectric forms in the pH range 4.58-5.15, while corresponding I-cell disease samples showed an absence of isoelectric forms in the pH range 4.99-5.15. Concanavalin A-Sepharose 4B chromatography of the I-cell disease mutant C.A. demonstrated a 31% and 37% decrease in the binding of 4-methyl-umbelliferyl-beta-D-galactosidase and GM1 beta-D-galactosidase activities, respectively, when compared to normal samples. Isoelectric focusing profiles of the concanavalin A-Sepharose 4B alpha-methyl-D-mannoside effluents containing normal and I-cell disease acid beta-D-galactosidase were generally similar, but the unadsorbed I-cell disease enzyme from concanavalin A-Sepharose 4B demonstrated more activity in the pH range 4.21-4.49 than normals. Normal and I-cell disease acid beta-D-galactosidase "A" and "B", separated by gel column chromatography were found to have similar properties with respect to apparent molecular weights pH vs. activity profiles and apparent Km values for the 4 methylumbelliferyl-beta-D-galactopyranoside, GM1-ganglioside and asialofetuin (ASF) substrates. However, the apparent V values for the ICD samples were consistently reduced when compared to the results obtained with the corresponding normal fractions. The greatest decreases in apparent V were obtained for acid beta-D-galactosidase activities in I-cell disease crude supernatant fluids, and for the separated I-cell disease "B" enzyme. The differences in the isoelectric focusing profiles, the altered binding to concanavalin A-Sepharose 4B, and the reduced V values with natural and synthetic substrates may be related to changes in carbohydrate composition of I-cell disease acid beta-D-galactosidase.
The X-ray spectrum of SN 1006

The supernova (SN) of A.D. 1006 represents the brightest in recorded history. The X-ray observations of its remnant appear to be full of puzzles. The present paper has the objective to reevaluate published X-ray data on SN 1006, using detailed nonequilibrium spectral computations and a self-consistent hydrodynamic SNR model. In a summary of the main conclusions, it is pointed out that an observed power-law continuum can be understood as mainly free-free emission from a reverse shock into SN ejecta with an initially uniform density profile. The spectral index is correctly predicted by such a model. Most of the continuum is produced by fully ionized gas in the dense outer layers of ejecta. The X-ray spectrum is not consistent with a solar composition or a uniform composition but is consistent with a layered composition of ejecta containing carbon on the outside, and processed heavy elements on the inside. There is no difficulty in including a large mass of iron.
Institutional Quality and Perceptions of Representation in Advanced Industrial Democracies

This study examines how well publics feel represented by their parliaments and governments in advanced industrial democracies. I argue that these perceptions are to a significant degree shaped by how well arbitrating institutions—bureaucracies and judiciaries—administer policies and adjudicate conflicts. A core premise is that the personal and salient character of contacts with these institutions informs citizens about how effectively other parts of a regime represent them. The results support the argument: When national administrative and judicial institutions work well, citizens are also more likely to believe that parliaments and governments account for their interests, net of economic factors. The main rival hypothesis receives surprisingly little support—a nation’s regime type exerts little influence on representational judgments.
Understanding Twitter data with TweetXplorer

In the era of big data it is increasingly difficult for an analyst to extract meaningful knowledge from a sea of information. We present TweetXplorer, a system for analysts with little information about an event to gain knowledge through the use of effective visualization techniques. Using tweets collected during Hurricane Sandy as an example, we will lead the reader through a workflow that exhibits the functionality of the system.
How to do resonant nuclear experiments with synchrotron radiation

The use of synchrotron radiation to excite low-lying nuclear resonances is a rapidly developing field showing great promise for hyperfine spectroscopy, phonon spectroscopy and kinetic studies, crystallography, and fundamental physics experiments. Recent technical advances in synchrotron sources, optics, and fast detectors have drastically increased signal rates and expanded the range of samples that can be studied. A typical experiment today uses a high-brightness synchrotron source having X-ray pulses well-separated in time, a meV-bandpass monochromator using perfect crystals of silicon or germanium, a sample containing resonant nuclei, and an avalanche photodiode timing detector. Both coherent and incoherent scattering can be observed; the coherent scattering is used for hyperfine spectroscopy and studies of diffraction interference phenomena, and the incoherent-scattering signal promises to be very useful for phonon spectroscopy and other studies of excitations in condensed systems. At this point seven nuclear isotopes have been used to resonantly scatter synchrotron radiation, but the number is rapidly increasing.
Mechanism of action of α-naphthoflavone as an Ah receptor antagonist in MCF-7 human breast cancer cells

alpha-Naphthoflavone (alpha NF) and 6-methyl-1,3,8-trichlorodibenzofuran (MCDF) inhibited 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced CYP1A1 gene expression in MCF-7 human breast cancer cells and also decreased the accumulation of the nuclear [3H]TCDD-aryl hydrocarbon (Ah) receptor complex. Nuclear extracts from cells treated with 10(-6) M alpha NF and incubated with a dioxin responsive element (DRE, 26-mer) did not form a retarded band in a gel mobility shift assay. In contrast, incubation of nuclear extracts from cells treated with 10(-6) M MCDF and DRE gave a retarded band and this is consistent with the antiestrogenic and Ah receptor agonist activity of MCDF in human breast cancer cells. alpha NF was further investigated as an Ah receptor antagonist by determining the inhibition by alpha NF of TCDD-induced antiestrogenicity in MCF-7 cells. TCDD (10(-9) M) inhibited the 17 beta-estradiol-induced proliferation of MCF-7 cells and the secretion of the 52-kDa protein. In cotreatment studies, alpha NF (10(-8) to 10(-6) M) caused a concentration-dependent decrease in the antiestrogenic responses elicited by TCDD. In addition, alpha NF inhibited the TCDD-induced down-regulation of nuclear estrogen receptor levels in MCF-7 cells. alpha NF (10(-6) M) alone was inactive as an estrogen or antiestrogen and in cotreatment studies did not affect 17 beta-estradiol-induced responses in MCF-7 cells. Tamoxifen (10(-7) M), an antiestrogen which acts through the estrogen receptor, also inhibited 17 beta-estradiol-induced cell proliferation and alpha NF did not affect the tamoxifen-mediated antiproliferative response. Thus, alpha NF antagonized TCDD-induced CYP1A1 gene expression in MCF-7 cells and also acted as an anti-antiestrogen for TCDD-mediated antiestrogenicity in these cells. These results were consistent with the low levels of DRE binding observed with nuclear extracts from cells treated with 10(-9) M TCDD plus alpha NF (10(-8) to 10(-6) M) or 10(-6) M alpha NF alone. Thus, alpha NF appears to act as an Ah receptor antagonist in MCF-7 cells by decreasing the levels of transcriptionally active nuclear Ah receptor complexes.
NiFe films deposited by sputter gun and applications to bubble devices

Abstract The sputter gun system has a unique feature which is that the substrate holder is electrically isolated from and physically outside the cathode and anode gun assembly. As a result the substrate surface temperature can be maintained at a lower level than that for the conventional diode sputtering system. This feature is particularly useful for metallization by the lift-off process. NiFe films with excellent physical and magnetic properties have been obtained. The application to overlay patterns for single-level masking bubble devices is presented.
Disinhibition of aggression through diffusion of responsibility and dehumanization of victims

The present study tested derivations from social learning theory on the disinhibition of aggression through processes that weaken self-deterring consequences to injurious conduct. Subjects were provided with opportunities to behave punitively under diffused or personalized responsibility toward groups that were characterized in either humanized, neutral, or dehumanized terms. Both dehumanization and lessened personal responsibility enhanced aggressiveness, with dehumanization serving as the more potent disinhibitor. Escalation of aggression under conditions of dehumanization was especially marked when punitiveness was dysfunctional in effecting desired changes. The uniformly low level of aggression directed toward humanized groups, regardless of variations in responsibility and instrumentality of the conduct, attested to the power of humanization to counteract punitiveness. Results of supplementary measures are consistent with the postulated relationship between self-disinhibiting processes and punitiveness. Dehumanization fostered self-absolving justifications that were in turn associated with increased punitiveness. Findings on the internal concomitants of behavior performed under different levels of responsibility suggest that reducing personal responsibility heightens aggressiveness more through social than personal sources of disinhibition.
Multi-utilization of Chicken Litter as a Biomass Source. Part II. Pyrolysis

To determine optimum conditions for producing activated carbon and carbon black from biomass waste (i.e., chicken litter), studies have been performed on the thermal decomposition changes of chicken litter under a nitrogen atmosphere by evolved gas analysis (EGA) including thermogravimetric mass spectrometry (TG-MS), TG-fourier transform infrared (TG-FTIR), and pyrolysis-GC/MS. Samples were prepared by milling and sieving the as-collected chicken litter to obtain three kinds of samples differing in particle size distribution (sample A, above 140 mesh; sample B, 140−325 mesh; sample C, below 325 mesh). Samples A and C were found to show the two extremes in volatile matter to ash content ratios of 54/25% and 35/54%. Thus, to obtain carbon byproducts at a higher yield, decomposition of sample A in nitrogen was studied in particular, and it was found that the process can be roughly divided in four stages. The activation energy, E, was also obtained by kinetic analysis for each of the stages: (I) release of a...
Functional relation between stimulus intensity and photically evoked cerebral responses in man.

Stimulus intensity and photically evoked cerebral response as possible objective index of brightness perception for man
Point transformations and scattering by a hard core

The scattering of a particle by a hard-core potential is considered from the point of view of co-ordinate transformations. A transformation that deforms the radial co-ordinate leads to a regular velocity-dependent potential and a modified static potential. The arbitrary function involved may be chosen to reduce the core to arbitrarily small size for the transformed Hamiltonian or to remove it completely. If the deformation extends over all space the phase shifts described by the new Hamiltonian are displaced by thes-wave contribution. If the deformation tends to zero at large distances, all the scattering is contained in the Hamiltonian. The transformation serves to generate a family of Hermitian, velocity-dependent potentials with the correct zero-energy scattering behaviour.
Transferability in XAFS

Abstract The transferability concept is central to all practical applications of XAFS for structure determination, both experimental and theoretical. In this paper the question of transferability in EXAFS is re-examines. Physical arguments ndicate that transferability is much less accurate for multiple scattering than for single scattering. Therefore caution must be used when using multiple scattering to obtain structural information. The effect of bond length on central atom absorption is briefly discussed.
The quality of social roles as predictors of morbidity and mortality

Abstract This study uses a longitudinal design to examine the health effects of the quality of social roles among a cohort of women and men. The specific roles of interest are the spouse role, the parent role, and the worker role. The cumulative and interactive effects of role characteristics and role satisfactions and stresses are also examined. The study population was randomly selected from among members of a large HMO and were part of a household interview conducted in 1970-71. Medical records for the 2 years prior to the interview and for 15 years after the interview for the cohort members are linked with the survey data. The findings show that for women, particular qualities of the marital and work roles are predictive of subsequent morbidity and mortality. For married women, equality in decision making and companionship in marriage are protective against death. None of the marriage characteristics are predictive of health outcomes among men. Work support is protective against death, malignancy, and stroke among employed women, and work stress increases the risk of ischemic heart disease among employed men. None of the parental role characteristics were significant predictors of health outcomes for men or women. No interaction were found.
Using parallel complex permeability for ferrite characterization

The authors address topics related to the characterization of linear ferrite materials using real and imaginary components of parallel permeability. Significant advantages are found in using the parallel rather than the usual series form of complex permeability to represent the performance of high-permeability ferrite cores. The findings include independence of the number of turns, a new equation for core loss density, a more direct examination of ferrite properties, and a reinterpretation of Snoek's limit. It is concluded that the parallel components of complex permeability provide direct measures of the inherent ferrite material properties. >
Observation of the 14 MeV resonance in 12C(p, p)12C with molecular ion beams

The lowest T = 32 state in ^(13)N has been observed using H_2^+ and H_3^+ molecular ion beams incident on ^(12)C. The dependence of the shape of the observed anomaly on the molecular-ion species and the target thickness is accounted for using the parameters of the molecular ions and a standard resonance shape determined using a proton beam. In addition to explaining the interaction of molecular ion beams with a thin target, these results provide a technique for extending precise energy-calibration standards to significantly higher energies.
Cognitive development in Silver‐Russell syndrome: a sibling‐controlled study

This study examined cognitive development in Silver-Russell syndrome (SRS), a condition with intrauterine growth retardation, persisting short stature, and specific stigmata. Neuropsychological function and cognitive abilities were assessed in a sample of 36 children with SRS (21 males, 15 females; mean age 7 years 6 months, SD 2 years 8 months; age range 3 to 12 years) and 25 normally developing siblings (mean age 8 years 6 months, SD 2 years 7 months; age range 3 to 12 years) using the Kaufman Assessment Battery for Children. Special measures were taken to control for confounding factors and sample bias. Mean overall IQ score in the total SRS sample (95.7, SD 10.63), as measured by the Mental Processing Composite Scale, was significantly reduced (p=0.021) compared with test norms (IQ 100, SD 15), indicating a moderate cognitive impairment. Subscale analysis revealed some specific deficiencies. However, these cannot be attributed to an established category of specific learning disorder. The mean score in the Achievement Scale (91.25, SD 14.92), which is more sensitive to educational influences, showed stronger deficits (p=0.001). The sibling control group achieved a slightly better mean IQ score (104.20, SD 12.32) than test norms (p=0.10). Direct analysis of paired differences between the subsample of children with SRS and a sibling among the control group (n=25) revealed a significant mean difference of 8.08 IQ points (p=0.011). Risk factor analysis revealed that cognitive development is not associated with birth length (p=0.404), birthweight (p=0.820), growth hormone therapy (p=0.810), phenotypic severity (p=0.828), or sex (p=0.880). Two children with maternal uniparental disomy for the entire chromosome 7 had markedly lower IQ scores (81 and 84 respectively). In contrast to the few previous findings, children with SRS show only moderate, but significant, impairments in cognitive outcome, which are more striking in our sample when compared with siblings than with test norms.
Optimization by ghost image processes in neural networks

Abstract We identify processes for structuring neural networks by reference to two classes of interacting mappings, one generating provisional outcomes (“trial solutions”) and the other generating idealized representations, which we call ghost images. These mappings create an evolution both of the provisional outcomes and ghost images, which in turn influence a parallel evolution of the mappings themselves. The ghost image models may be conceived as a generalization of the self-organizing neural network models of Kohonen. Alternatively, they may be viewed as a generalization of certain relaxation/restriction procedures of mathematical optimization. Hence indirectly they also generalize aspects of penalty based neural models, such as those proposed by Hopfield and Tank. Both avenues of generalization are “context free”, without reliance on specialized theory, such as models of perception or mathematical duality. From a neural network standpoint, the ghost image framework makes it possible to extend previous Kohonen-based optimization approaches to incorporate components beyond a visually oriented frame of reference. This added level of abstraction yields a basis for solving optimization problems expressed entirely in symbolic (“non-visual”) mathematical formulations. At the same time it allows penalty function ideas in neural networks to be extended to encompass other concepts springing from a mathematical optimization perspective, including parametric deformations and surrogate contractions . This paper demonstrates the efficacy of ghost image processes as a foundation for creating new optimization approaches by providing specific examples of such methods for covering, packing, generalized covering, fixed charge and multidimensional knapsack problems. Preliminary computational results for multidimensional knapsack problems are also presented.
Deriving private information from randomized data

Randomization has emerged as a useful technique for data disguising in privacy-preserving data mining. Its privacy properties have been studied in a number of papers. Kargupta et al. challenged the randomization schemes, and they pointed out that randomization might not be able to preserve privacy. However, it is still unclear what factors cause such a security breach, how they affect the privacy preserving property of the randomization, and what kinds of data have higher risk of disclosing their private contents even though they are randomized.We believe that the key factor is the correlations among attributes. We propose two data reconstruction methods that are based on data correlations. One method uses the Principal Component Analysis (PCA) technique, and the other method uses the Bayes Estimate (BE) technique. We have conducted theoretical and experimental analysis on the relationship between data correlations and the amount of private information that can be disclosed based our proposed data reconstructions schemes. Our studies have shown that when the correlations are high, the original data can be reconstructed more accurately, i.e., more private information can be disclosed.To improve privacy, we propose a modified randomization scheme, in which we let the correlation of random noises "similar" to the original data. Our results have shown that the reconstruction accuracy of both PCA-based and BE-based schemes become worse as the similarity increases.
TH-A-BRA-07: Optimization of Gamma Parameters for EPID-Based Pretreatment Detection of Delivery Errors in IMRT Fields

Purpose: Gamma analysis is widely used for intensity modulated radiation therapy(IMRT)quality assurance. However, when calculated on a discrete grid with conventional dose/distance criteria of f_dose = 3%/f_dist = 3mm, gamma exhibits poor correlation with dose errors and poor specificity/sensitivity for detecting fluence deviations. This work shows how gamma criteria may be optimized for error detection, and uses repeat images of 11 clinical IMRT fields to quantify delivery errors that can be reliably detected via optimal analysis of electronic portal (EPID)images.Methods: Multiple EPIDimages were acquired of 11 clinical IMRT fields. For each field, images were aligned and averaged, generating a reference image. Gamma was computed for individual images relative to reference using two methods: discrete grid (0.37mm2 pixel size) and continuous (interpolation‐ free). Rectangular errors were inserted into measured images, and receiver operating characteristic (ROC) studies determined parameters that yield maximum image classification accuracy. Classification was deemed reliable if =95% of images were correctly classified. Results: Key parameters are f_grad=0.37xf_dose/f_dist and the gamma distribution tail cutoffs used to classify images as errored or error‐free. f_grad controls the ‘looseness’ of the distance‐to‐agreement (DTA) search. Classification is optimal when f_grad is loose enough to ignore normal image‐to‐image variations, but tight enough to detect delivery errors. Conventional 3%/3mm criteria give sub‐ optimal error detection. Even with optimal parameters, calculation on a discrete grid introduces sufficient sampling errors as to seriously degrade error detection. If continuous gamma calculation is employed with optimal parameters, one can reliably detect small errors, e.g., dose deviations of 5‐ 10% over areas of 3×3 pixels (∼1mm2) at isocenter. Conclusions: Optimal detection of IMRTdelivery errors using EPIDimages is achieved with continuous gamma, and optimal criteria (f_dose, f_dist and classification cutoffs). Caution must be exercised when gamma is calculated on a discrete grid using conventional 3%/3mm criteria. Research funding from Varian Medical Systems.
Differential effects of pharmacological agents acting on monoaminergic systems on drug-induced anorexia

Abstract 1. 1. The mechanism of action of anorexigenic drugs has been clarified in recent years mainly as the result of drug interaction studies employing pharmacological agents that rather selectively affect monoaminergic neurotransmitter processes. 2. 2. A subdivision of anorectic drugs has emerged with compounds being classified as either amphetamine-like, acting via a catecholaminergic mechanism, or fenfluramine-like, exerting their anorectic effect primarily through endogenous neuronal serotonin or directly on receptors for serotonin. Amphetamine, mazindol, diethylpropion and phentermine fall in the first group, while the second category includes fenfluramine, m-chlorophenylpiperazine, quipazine and MK-212 (6-chloro-2-[1-piperazinyl]-pyrazine). 3. 3. The most consistent evidence supporting the subdivision of anorexigens comes from studies with pharmacological antagonists. Blockers of receptors for catecholamines, e.g. haloperidol, antagonize the anorectic effect of amphetamine and related substances without causing a similar inhibition of fenfluramine and other fenfluramine-like anorexigens. Conversely, methergoline, an antagonist of serotonin, causes a clear inhibition of drugs in the fenfluramine-like category, but not those in the amphetamine-like group. 4. 4. Supporting evidence, while not always consistent from laboratory to laboratory, derives from investigations using inhibitors of monoamine synthesis, neurotoxins such as 6-hydroxydopamine and 5,6-dihydroxytryptamine and inhibitors of the monoaminergic uptake processes.
Towards a valid measurement of monitored knowledge

This paper provides a number of reflections on the difficulties involved in measuring monitored knowledge of second language grammar, and describes the construction and validation of a prototype test for measuring this knowl edge. It is argued that a fill-in-the-blanks format is to be preferred over multi ple choice, grammaticality judgement or error correction tasks. Problems in defining the structures to be tested are discussed, and a pragmatic solution is proposed. The psychometric characteristics of three versions of the prototype test are described, based on the results obtained for 62 learners of French as a second language in their last year of high school in Dutch-speaking Belgium.
Sequential bond energies of Pt(CO)x + (x = 1 -4) determined by collision-induced dissociation

The sequential bond energies of Pt(CO)x+ (x = 1−4) are determined by collision-induced dissociation with Xe using guided-ion beam tandem mass spectrometry. Analysis of the kinetic energy dependent cross sections yields 0 K bond energies in eV (kJ/mol) of 2.20 ± 0.10 (212 ± 10), 2.00 ± 0.10 (193 ± 10), 1.02 ± 0.05 (98 ± 5), and 0.55 ± 0.05 (53 ± 5) for (CO)x-1Pt+−CO with x = 1−4, respectively. These values are in reasonable agreement with results of density functional ab initio calculations in the literature. D0(Pt+−Xe) is determined as 0.86 ± 0.30 eV (83 ± 29 kJ/mol) from analysis of the ligand exchange reaction with PtCO+. The trend in these bond energies is compared with those of nickel and sodium carbonyl cations and discussed in terms of sdσ hybridization, electrostatic interactions, and ligand−ligand steric interactions.
Synthesis, characterization, and Fischer-Tropsch studies of iron-containing zeolites

Iron has been incorporated into several zeolites with adsorption, ion-exchange, and anionic complexation procedures. These samples have been reduced in flowing hydrogen at temperatures between 300 and 500 °C. Particle size measurements using X-ray powder diffraction and electron microscopy techniques reveal that all of the iron phases of the reduced samples are between 50 and 150 A. Changes in the catalysts due to their interactions with 10% COH2 at temperatures ranging from 260 to 400 °C were determined by Mossbauer spectroscopy using an in situ cell. Catalytic activity was monitored by a gas chromatograph and quantitative analysis of the product distribution was done in a separate differential reactor which was interfaced to a mass spectrometer. Alloy formation was not observed.
Analysis of picogram quantities of protein in subnanoliter-size samples

The ability to measure protein concentration in subnanoliter volumes would be helpful in many biological studies. A microassay for measuring nanogram protein quantities in nanoliter-size samples and an ultramicroassay for measuring picogram quantities in picoliter samples were developed to measure lymphatic protein concentration. Aliquots of a sample solution were mixed with an o-phthalaldehyde mercaptoethanol reagent using micropipetting techniques. Reaction product fluorescence was measured using a modified Leitz MPV-1 microscope as a microfluorometer. Fluorescence varied linearly with albumin concentrations between 1 and 8 g/100 ml. A typical microassay measuring albumin standards at 0.0, 1.0, 2.0, and 4.0 g/100 ml yielded a linear regression of y = 207x + 60 (r = 0.99). Minimum detectable protein concentration was 0.125 g/100 ml. The SE for the albumin standards varied from 0.02 to 0.17 g/100 ml. An ultramicroassay measuring similar standards yielded a linear regression of y = 1180x + 109 (r = 0.96). Minimum detectable protein concentration was 0.028 g/100 ml. The SE for the standards varied from 0.01 to 0.32 g/100 ml.
Constraints on Circumstellar Disk Parameters from Multiwavelength Observations: T Tauri and SU Aurigae

We present circumstellar disk models for two pre-main-sequence objects, T Tau and SU Aur. The models are based on interferometric data from infrared and millimeter wavelengths and infrared photometry from the literature. The physical properties of the disk are examined by calculating parameter probabilities based on a passive, flat-disk model. The model adequately fits the data for SU Aur but not for T Tau. We find that there are significant differences in the physical parameters suggested by the individual data sets. The size of the inner disk radius as implied by the infrared interferometry data (~tenths of AU) is larger than expected for a flat-disk model. This discrepancy is discussed in consideration of more complex disk models that include the presence of a hot, inner region or wall in the disk.
Compression injury in the mouse spinal cord elicits a specific proliferative response and distinct cell fate acquisition along rostro-caudal and dorso-ventral axes

Harnessing the regenerative capabilities of endogenous precursor cells in the spinal cord may be a useful tool for clinical treatments aimed at replacing cells lost as a consequence of disease or trauma. To better understand the proliferative properties and differentiation potential of the adult spinal cord after injury, we used a mouse model of compression spinal cord injury (SCI). After injury, adult mice were administered BrdU to label mitotic cells and sacrificed at different time-points for immunohistochemical analysis. Our data show that the rate of proliferation increased in all regions of the spinal cord 1day after injury, peaked after 3days, and remained elevated for at least 14days after injury. Proliferation was greater at the injury epicenter than in rostral and caudal adjacent spinal segments. The number of proliferative cells and rate of proliferation varied between dorsal and ventral regions of the spinal cord and between the gray and white matter. Newly generated cells expressed markers for progenitor cells (Nestin and Olig2), oligodendrocytes (Sox10), astrocytes (S100b and glial fibrillary acidic protein), and microglia (Iba1), but not neuronal markers (Map2 and NeuN). Marker expression varied with regard to the dorso-ventral region, rostro-caudal proximity to the injury epicenter, and time after injury. At early time-points after injury, BrdU(+) cells mainly expressed microglial/macrophage and astrocytic markers, while at these same time-points in the control spinal cord the mitotic cells predominately expressed oligodendrocyte and oligodendrocyte progenitor cell markers. The profile of proliferation and cell fate marker expression indicates that after moderate compression, the spinal cord has the capacity to generate a variety of glial cells but not neurons, and that this pattern is space and time specific. Future studies should focus on ways to control proliferation and cell fate after injury to aid the development of cell replacement treatments for SCI.
Nice decompositions of R n entirely into nice sets are mostly impossible

While there are several interesting examples of partitions of R 3 into elements which individually are geometrically ‘nice’ — circles or segments — the partitions themselves fail to be ‘nice’, in the sense of forming continuous or upper semicontinuous decompositions. We show that this is no accident: R 3 has no continuous decomposition into circles, and no open subset of R n has an upper semicontinuous decomposition into convex compact nonsingleton sets.
Near-infrared spectrometric determination of di- and tripeptides synthesized by a combinatorial solid-phase method.

A new method based on near-infrared (NIR) spectrometry and partial least-squares analysis has been developed for the noninvasive and nondestructive determination of the identity and sequences of amino acid residues in di- and tripeptides. The di- and tripeptides were synthesized from six amino acids with similar structures (Gly, Ala, Leu, Met, Phe, Val) on two different polymer beads (bead with and without a linker) using the solid-phase peptide synthetic method. The developed NIR method is capable of determining the identity of sequences of these di- and tripeptides (with and without the Fmoc protecting group) directly on the polymer beads. It can distinguish not only dipeptides from tripeptides but also peptides with very similar structures (e.g., bead-Gly-Ala-Ala, bead-Gly-Ala-Phe, bead-Gly-Ala-Leu, bead-Gly-Ala-Val, and bead-Gly-Ala-Met). More importantly, the method is capable of distinguishing di- and tripeptides with the same amino acid residues but different sequences (e.g., bead-Gly-Leu-Val from ...
The distinction by light and electron microscopy of two types of cone containing colorless oil droplets in the retina of the turtle

Abstract In turtle retina the spectral types of cones can be distinguished by the characteristic colors of their oil droplets. Blue cones until recently were thought to be identified by their colorless oil droplets. Now it has been shown that the cones containing colorless oil droplets can be subclassified into two types: one type in which the oil droplet fluoresces under ultraviolet stimulation and the other type in which it does not. We have attempted to recognize these two subclasses of cones with colorless oil droplets by the following anatomical techniques. (1) Light microscopy of fresh retina, (2) light microscopy of isolated cells in tissue culture and (3) light and electron microscopy of photoreceptors stained with horseradish peroxidase in whole-mount. The cone type with the colorless fluorescent oil droplet (FC cone) has an oil droplet size intermediate between those contained in the green single cones and the cone with the clear colorless oil droplet (CC cone); it typically has a short (15μm long) oblique axon and it forms approximately 13% of the cones in the retina. The CC cone, on the other hand, is recognized by having the smallest oil droplet of all cone types which is nonfluorescent; it has a very long (30 μm long) oblique axon and forms 5% of the cones in the retina. We discuss the similarity of the FC cone morphology and distribution to blue cones in other vertebrate retinas.
Biochemical effects of repeated administration of P,p'-DDT on the squirrel monkey.

Abstract p,p′ -DDT was administered po in peanut oil to 5 groups of 6 squirrel monkeys at doses of 50, 5, 0.5, 0.05, and 0 mg/kg/day. Blood samples were taken weekly from each animal; several hematologic parameters were determined, and plasma amylase, aldolase, glutamic-pyruvic transaminase, and isocitric dehydrogenase were measured. Two monkeys from each group were killed after 2, 4, and 6 mo and in vitro liver homogenate enzyme activity was measured using p -nitroanisole and ethyl p -nitrophenyl phenylphosphonothioate as substrates. No discernible effects on hematologic values or plasma enzyme levels were observed. The stimulation of the 2 liver homogenate mixed-function oxidases was maximal after 2 mo treatment. There were no significant differences in the levels of homogenate enzyme activity at the 3 sacrifice periods. The monkeys given 50 mg/kg/day all died within 14 wk of starting treatment; deaths did not occur at the other doses.
DNA-Mediated Electron Transfer: A Sensitive Probe of DNA-Protein Interactions

The ability of the π-stacked array of heterocyclic DNA bases to behave as an efficient conduit for charge migration has been explored using a wide array of experimental approaches. Spectroscopic studies and biochemical assays show that charge transfer through well-stacked DNA can be extremely facile, although sensitive to structural distortions within the DNA base stack. The efficiency of these long-range reactions depends upon the coupling of the electron donor, acceptor and intervening base pairs within the base stack. As a result, base mismatches and stacking disruptions associated with protein binding to the helix can significantly perturb long range charge transfer. DNA-protein interactions which result in the base flipping of a nucleotide out of the DNA π-stack, in particular, dramatically inhibit long-range charge transfer through DNA. Whether these reactions that can occur over large molecular distances, be applied in sensing DNA damage, and be modulated by DNA-binding proteins, are exploited within the cell remains to be determined.
Local shear and mass transfer on individual coral colonies: Computations in unidirectional and wave-driven flows

Flows through single coral colonies were simulated with an implementation of the Immersed Boundary (IB) method in Large-Eddy Simulation (LES). The method was first validated with magnetic velocimetry experiments, which demonstrated that computational results were within approximately 7% of flow measurements. The algorithm was then applied to simulate unidirectional and wave-driven flow conditions through two morphologically distinct coral colonies that naturally grow in very different hydrodynamic environments, with detailed analysis on spatial hydrodynamic and mass transfer variability. When the hydrodynamics of each coral's native environment was simulated, the dynamics in the interior of both branching species appeared to converge, in spite of vast differences between the hydrodynamic conditions and morphologies. A correlation between local surface shear and mass transfer was derived from simulated data. The results suggest that the corals grew in such a way that mass transfer characteristics are similar despite of vast differences in their physical shapes and hydrodynamic conditions.
Distribution effects and the business demand for money

Abstract This paper examines whether and how changes in an industry's firm-size distribution affect the per-firm demand for money. The size distribution of an industry potentially affects the demand for money through several channels. We examine four of those channels: 1) economies of scale; 2) decentralization in cash management; 3) cost of credit; and 4) compensating balances. We conclude that increasing the size inequality increases the industry's per-firm demand for money.
Interaction Between Nickel and Iron in the Rat

The interaction between nickel and iron was confirmed in rat metabolism. In a fully-crossed, two-way, three by four, factorially designed experiment, female weanling rats were fed a basal diet supplemented with iron at 0, 25, 50, and 100 μg/g and with nickel at 0, 5, and 50 μg/g. The basal diet contained about 10 ng of nickel and 2.3 μg of iron/g. After nine weeks, dietary iron affected growth, hematocrit, hemoglobin, plasma cholesterol, and in liver affected total lipids, phospholipids, and the contents of copper, iron, manganese, and zinc. By manipulating the iron content of the diet, effects of dietary nickel were shown in rats that were not from dams fed a nickel-deprived diet. Nickel affected growth, hematocrit, hemoglobin, plasma alkaline phosphatase activity, plasma total lipids, and in liver affected total lipids, and the contents of copper, manganese, and nickel. The interaction between nickel and iron affected hematocrit, hemoglobin, plasma alkaline phosphatase activity, and plasma phospholipids, and in liver affected size, content of copper, and perhaps of manganese and nickel. In severely iron-deficient rats, the high level of dietary nickel partially alleviated the drastic depression of hematocrit and hemoglobin, and the elevation of copper in liver. Simultaneously, high dietary nickel did not increase the iron level in liver and was detrimental to growth and appearance of severely iron-deficient rats. In nickel-deprived rats fed the borderline iron-deficient diet (25 μg/g) hematocrit and hemoglobin also were depressed. However, 5 μg Ni/g of diet were just as effective as 50 μg Ni/g of diet in preventing those signs of nickel deprivation. The findings in the present study suggested that nickel and iron interact with each other at more than one locus.
Computationally Linking Molecular Features of Conjugated Polymers and Fullerene Derivatives to Bulk Heterojunction Morphology

The efficiency of bulk heterojunction solar cells depends strongly on the morphology of the electron donors (conjugated polymers) and electron acceptors (fullerene derivatives) in the active layer. The features of the donor–acceptor morphology (e.g., domain shapes, crystalline/amorphous domains, and donor–acceptor interface) can in principle be tuned by choosing the chemistry and architecture of the conjugated polymer, fullerene functional group, solvents, and processing conditions (e.g., annealing temperature). Here, we present a high-throughput coarse-grained simulation study that links molecular-level design parameters to features in the assembled morphology in neat polymers and donor–acceptor blends. These models reproduce neat polymer morphologies observed in experiments, such as lamellae, hexagonally packed cylinders, and acceptor intercalation among donor side chains. Furthermore, for blends of conjugated polymers and fullerene derivatives, this study shows how conjugated polymer architecture and a...
Splicing of an anti-sense alu sequence generates a coding sequence variant for the α-3 subunit of a neuronal acetylcholine receptor

Abstract In this report we demonstrate that an α-3 acetylcholine receptor subunit transcriptional variant originates through alternative splicing of a complementary sequence of the right arm of an Alu element. This element is located within the 5.1Kb intron found between axons 5 and 6 of the α-3 acetylcholine receptor subunit gene. The transcriptional variant originates from the normal splicing process and carries an in-frame stop codon. If translated, it should encode for a peptide lacking the 4th transmembrane domain of the normal subunit.