cssi/SciSciGPT-SciSciNet huggingface dataset:
Kinetic study of olefin polymerization with a supported metallocene catalyst. I. Ethylene/propylene copolymerization in gas phase

A kinetic study of ethylene homopolymerization and copolymerization is conducted with a supported metallocene catalyst in a gas-phase reactor. An experimental procedure is developed that minimizes the effect of impurities in the reactor and simultaneously yields consistent and reproducible reaction-rate data. The effects of operational parameters such as reaction temperature, pressure, and comonomer concentration on the kinetics of both homopolymerization and copolymerization are investigated. Online perturbation techniques are implemented to determine key kinetic parameters such as the activation energies for ethylene propagation and catalyst deactivation. A reaction-rate order close to 2 is obtained for ethylene homopolymerization from pressure perturbations, while near to first-order dependency is observed in the presence of propylene. To quantify the effects of the operational parameters, a one-site kinetic model for homopolymerization and a two-site kinetic model for copolymerization are proposed. The necessary kinetic parameters in the model are estimated using the POLYRED™ package. The resulting kinetic model represents the kinetic data over a wide range of conditions for this supported metallocene catalyst. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 81–114, 2001
Systematic development of hybrid cybernetic models: Application to recombinant yeast co‐consuming glucose and xylose

The hybrid cybernetic modeling approach of Kim et al. (Kim et al. [2008] Biotechnol. Prog., in press) views the substrate uptake flux in microorganisms as being distributed in a regulated way among different elementary modes (EMs) of a metabolic network, which intracellular fluxes related to the uptake rates by the pseudo-steady-state approximation on intracellular metabolites. While the conceptual development has been demonstrated by Kim et al. (Kim et al. [2008] Biotechnol. Prog., in press) using a rather simple example (i.e., Escherichia coli metabolizing a single substrate), its extension to a larger scale network involving multiple substrates results in serious overparameterization (which implies an excessive number of parameters relative to the measurements available to determine them). Through the case study of recombinant Saccharomyces yeast co-consuming glucose and xylose, we present a systematic way of formulating a minimal order hybrid cybernetic model (HCM) for a general metabolic network. The overparameterization problem mostly arising from a large number of EMs is avoided using a model reduction technique developed by Song and Ramkrishna (Song and Ramkrishna [2009a] Biotechnol. Bioeng. 102(2):554-568) where an original set of EMs is condensed to a much smaller subset. Detailed discussions follow on the issue of determining the minimal set of active modes needed for the description of the simultaneous consumption of multiple substrates. The developed HCM is compared with other metabolic models: macroscopic bioreaction models (Provost et al. [2006] Bioprocess Biosyt. Eng. 29(5-6):349-366), and dynamic flux balance analysis. It is shown that the HCM outperforms the other two as validated using various sets of fermentation data. The difference among the models is more dramatic in a situation such as the sequential utilization of glucose and xylose, which is observed under realistic fermentation conditions.
Inhibition of Protein-tyrosine Phosphatase Stimulates the Dynamin-dependent Endocytosis of ROMK1

We have previously shown that inhibiting protein-tyrosine kinase increased whereas inhibiting protein-tyrosine phosphatase (PTP) decreased renal outer medullary potassium channel 1 (ROMK1) channel activity (1). We have now used confocal microscopy, the patch clamp technique, and biotin labeling to further examine the role of tyrosine phosphorylation in regulating ROMK1 trafficking. Human embryonic kidney 293 cells were cotransfected with c-Src and green fluorescent protein-ROMK1, which has the same biophysical properties as those of ROMK1. Patch clamp studies have shown that phenylarsine oxide (PAO), an inhibitor of PTP, decreased the activity of ROMK1. Moreover, addition of PAO reduced the cell surface localization of green fluorescent protein-ROMK1 detected by confocal microscopy and diminished the surface ROMK1 density by 65% measured by biotin labeling. Also, PAO treatment significantly increased the phosphorylation of ROMK1. The notion that the effect of PAO is mediated by stimulating tyrosine phosphorylation-induced endocytosis of ROMK1 has also been supported by findings that mutating the tyrosine residue 337 of ROMK1 to alanine abolished the effect of PAO. Finally, the inhibitory effect of PAO on ROMK1 was completely blocked in the cells co-transfected with dominant negative dynamin (dynaminK44A). This indicates that the tyrosine phosphorylation-induced endocytosis of ROMK1 is dynamin-dependent. We conclude that inhibiting PTP increases ROMK1 phosphorylation and results in a dynamin-dependent internalization of the channel.
Reinforcing value of food in obese and non-obese women.

Food is a powerful reinforcer, and individual differences in the reinforcing efficacy of food may provide a mechanism to explain the excess intake and positive energy balance responsible for obesity. The present study tested the hypothesis that eating palatable food would be more reinforcing than engaging in sedentary activities (e.g. playing computer games) for obese in comparison to non-obese non-dietary restrained female college students. Subjects could choose to eat food or engage in sedentary activities based on their responding in a computer-generated concurrent schedules task. The reinforcement schedule associated with earning access to sedentary activities was held at variable ratio 2 (VR2) while the food reinforcement schedule was set at VR2 in the first trial of the choice task and doubled across the four subsequent trials from VR4 to VR32. Choice and consumption results indicated that eating was significantly more reinforcing than engaging in sedentary activities for obese subjects than non-obese subjects. Hedonics for the activities and foods were not correlated with total food reinforcers earned and did not differ between the groups. These results confirm the hypothesis that eating food is more reinforcing than selected alternative activities to a greater extent for obese than for non-obese young women.
On the Second Painleve Transcendent

Numerical and asymptotic approximations to the second Painleve transcendent, F ± ( z; a ), as determined by the solution of F" – zF ± 2 F 3 = 0 and F ~ a Ai ( z ) ( z ↑ ∞), are presented. The solution for F + is finite for all real z and 0 a 2 F - has at least one pole on the real axis if a 2 > 1. The asymptotic behaviour of F ± in the oscillatory regime ( – z ± 2F 2 > 0 ), which bears a qualitative resemblance to that of Ai ( z ), is determined for a 2 ≪ 1 and for ± ln (1 ± a 2 ) ≫ 1. The results are relevant for several recent investigations of nonlinear wave motion.
Nuclear magnetic resonance study of water adsorbed on cellulose

Abstract Nuclear magnetic resonance longitudinal and transverse NMR relaxation times are measured for water in frozen suspensions of cellulose as a function pf temperature. The nonexponential longitudinal relaxation observed is discussed in terms of a cross relaxation mechanism that accounts well for the data and which does not require that the water molecule lifetimes at the cellulose surface be long, i.e., on the order of tens of milliseconds as previously suggested. The temperature dependence of the proton relaxation data is similar to other liquid-solid interfacial systems. The slowly relaxing longitudinal 1H2O relaxation component may be fit to a log normal distribution of correlation times; however, the validity of this approach is seriously questioned in part because a significant contribution from anisotropic motion to relaxation events is demonstrated by observation of deuterium quadrupole splitting in the frozen suspension. An alternate hypothesis is presented to account qualitatively for the NMR relaxation data that does not involve a distribution of correlation times, but does include effects of anisotropic water molecule motion and intermolecular relaxation contributions.
Heart rate recorder

We describe the design of an instrument that can acquire and store the average heart rate of a subject over 256 time intervals of predetermined length (1 or 6 min) during normal daily activities. The instrument consists of two units: a portable recorder, worn by the patient, detects and counts heart beats, and stores their average in memory, and a display later retrieves the contents of that memory. C.M.O.S. technology and programmable operational amplifiers resulted in low power consumption (20 mW). The results obtained from this instrument were accurate to about 1 beat/min compared with Holter monitoring and telemetry.
Dark Matter Determinations from Chandra Observations of Quadruply Lensed Quasars

We present Chandra X-ray observations of 14 quadruply lensed quasars. The X-ray data reveal flux ratio anomalies which are more extreme than those seen at optical wavelengths, confirming the microlensing origin of the anomalies originally seen in the optical data. The reduction of the anomalies in the optical, as compared to X-ray, indicates that the sizes of the optical emitting regions of the quasars must be about 1/3 the size of the projected Einstein radii of the microlensing stars. The X-ray emitting regions are essentially point sources and therefore give a microlensing signal unencumbered by source size considerations. For each lensing galaxy, we determine the most likely ratio of smooth material (dark matter) to clumpy material (stars) to explain the X-ray flux ratios. The ensemble of Chandra-observed quads indicates that the amount of matter projected along the lines of sight to the images (at radial distances of several kpc from the centers of the lensing galaxies) is ~90% smooth dark matter and ~10% stars.
How automatic and representational is empathy, and why

The claim that empathy is both automatic and representational is criticized as follows: (a) five empathy-arousing processes ranging from conditioning and mimicry to prospective-taking show that empathy can be either automatic or representational, and only under certain circumstances, both; (b) although automaticity decreases, empathy increases with age and cognitive development; (c) observers' causal attributions can shift rapidly and produce more complex empathic responses than the theory allows.
THE OPTIMALITY OF THE “CUT ACROSS THE BOARD” RULE APPLIED TO AN INVENTORY MODEL

A common procedure in budget allocation is to let the different entities of an organization determine their optimal budgets. Once the individual requests are received, they are then cut by a common factor, as necessary, so that a global constraint is satisfied. We refer to this procedure as the “cut across the board” rule. In general, this method will not result in a globally optimal solution. In this paper we identify conditions that assure the global optimality of die “cut (or expand) across the board” rule. We specifically focus on a constrained multi-item inventory model and generalize results of Rosenblatt [10] and Plossl and Wight [8]. In addition, we briefly discuss applicability of the results to other areas.
Secure pairing of interface constrained devices

Secure initial pairing of electronic gadgets is a challenging problem because of the usual lack of a common security infrastructure and the threat of so-called Man-in-the-Middle (MiTM) attacks. A number of techniques have been proposed to address the problem, but many are not applicable to devices lacking required interfaces, such as displays or speakers. In this paper, we introduce a new secure device pairing concept that involves using the human body either as the communication medium for - or the source of - the common secret. We implement the concept as a suite of practical pairing protocols for interface constrained devices.
Adaptive approximation of solutions to problems with multiple layers by Chebyshev pseudo-spectral methods

We develop and analyze a family of mappings which enhance the accuracy of Chebyshev pseudo-spectral methods in approximating functions with multiple regions of localized rapid variation (layers). The mapping family depends on 3N {minus} 1 free parameters, where N is the number of layers. N parameters depend upon the locations of the layers and on the widths of the layers, while the other N {minus} 1 parameters depend on the resolution of each layer relative to the first layer. The parameters can be determined adaptively by minimizing a functional which measures the error of the approximation. Techniques to simplify the minimization process are developed. We further demonstrate that the appropriate choice of mappings can lead to a significant reduction in the condition number of matrices associated with Chebyshev pseudo-spectral differentation. We illustrate the effectiveness of the proposed mapping and adaptive procedure by examples in which we approximate (i) given functions exhibiting multiple layers and (ii) the solution of a system of partial differential equations modeling combustion in counterflowing jets so that two distinct flames occur. 24 refs., 8 figs., 5 tabs.
An application of equivalent modons to atmospheric blocking

Abstract Certain consistent features are demonstrated between a particular strong, vortex pair atmospheric blocking pattern over the eastern North Atlantic Ocean and Europe during January 1963 and an equivalent modon solution of the inviscid equivalent barotropic equation. Modons are uniformly translating, shape preserving, non-linear analytic solutions. The equivalent barotropic model for the atmosphere is derived as a lowest-order truncation of an expansion and projection of the quasigeostrophic equations with the empirical orthogonal pressure modes of the troposphere. The horizontal and vertical structure of the blocking pattern, as well as its intensity, are consistent with the modon dispersion relation. On the other hand, there remain some uncertainties about whether the pressure profile of the mean zonal wind is consistent with modon requirements and whether a stationary theoretical solution adequately reflects the essential dynamics of a fluctuating and regenerative blocking pattern.
Effects of restraint on electroencephalographic variables and monomethylhydrazine-induced seizures in the cat.

Abstract The toxic derivative of hydrazine, monomethylhydrazine, at a dosage of 10 mg/kg is a potent convulsant, producing tonic-clonic seizures in the cat. In this study the effects of enforced restraint on susceptibility to MMH-induced seizures was examined in naive animals and in cats prepared neurosurgically with indwelling polygraphic recording electrodes. Using a counterbalanced design, latency to seizure following the intraperitoneal administration of the drug (10 mg/kg) was measured twice in all animals, under restraint and in freely moving conditions. Susceptibility to seizures was significantly decreased under the condition of restraint. Additionally, polygraphic recordings showed that restraint was accompanied by an increased incidence of “synchronous” EEG patterns. These results were not explained by metabolic variables, duration of intertrial interval, or changes in weight. The relationship between observed polygraphic patterns and seizure response is discussed in terms of the physiological alterations attendant upon restraint.
Management strategies for patients with cytomegalovirus retinitis

Each of the available antiviral agents has significant advantages and disadvantages, and the choice of therapy must include consideration of the extent and location of the eye disease, the patient's lifestyle and medical history, and the potential for drug interactions with the many other medications that a patient with advanced AIDS may be receiving. Treatment of CMV retinitis requires the active participation of several dedicated health care providers: the primary care physician, the ophthalmologist, nurses, and social workers. All are integral parts of a clinical treatment team engaged in providing optimal therapy. Most important, it is critical for patients to be involved with their own health care. Patients should be taught to recognize early signs of decreased vision and should be involved in important decision-making steps for their own treatment.
Evaluation of 3-methylpyrazole-1-carboxamide as a soil nitrification inhibitor.

Laboratory studies to evaluate 3-methylpyrazole-1-carboxamide (MPC) as a soil nitrification inhibitor showed that it was comparable to nitrapyrin (N-Serve) for inhibiting nitrification of ammonium in soil, but was not as effective as etridiazole (Dwell) or 2-ethynylpyridine. They also showed that the effectiveness of MPC as a soil nitrification inhibitor is markedly affected by soil type and soil temperature, that MPC is more effective for inhibiting nitrification of ammonium-N than of urea-N, and that MPC has little, if any, effect on hydrolysis of urea or denitrification of nitrate in soil. These observations and other work discussed indicate that MPC is one of the most promising compounds so far proposed for inhibition of nitrification in soil.
Localization of Image State Electrons in the Sulfur Headgroup Region of Alkanethiol Self-Assembled Films

The experimental observation of electronic Raman scattering between image potential surface states is described and has been observed from roughened Au and Ag surfaces covered with long-chain alkanethiol self-assembled monolayers. To simulate the effect of surface roughness, interactions of the image state electron are modeled using a potential that incorporates two orthogonal metal surface planes, as would be expected near a step edge. Although the Raman spectra indicate that the image state electron exists within the film, modeling suggests more specifically that the electron is constrained to move within the sulfur headgroup layer. Although it is commonly accepted that the headgroup binding and structure on these surfaces is identical for both the short and the long chain alkanethiol homologues, these results highlight dramatic differences in the Au/S interfacial electronic structure between these two chain length regimes at room temperature.
Determination of ketoses by ultraviolet absorption following thermal hydrolysis

Abstract The hydrolysis of fructose, sorbose, tagatose, mannoheptulose and sedoheptulose in 4 N HCl at 80 °C results in the production of ultraviolet absorbing materials. This forms the basis of a sensitive method for the quantitative determination of these sugars. Optimum conditions for the determination of the individual ketoses were found. Aldohexoses, 6-deoxyhexoses, 2-deoxy- d -glucose, d -glucoheptose and sugar alcohols do not interfere with the method. Ribose produced significant interference.
α-Interferon therapy of chronic hepatitis B. Current status and recommendations

Antiviral therapy for chronic hepatitis B is still experimental. Recent studies suggest that a 3- to 6-month course of alpha-interferon in doses ranging from 5-10 million units (5 million units/m2) given daily or three times weekly will result in a clinical, biochemical and serological remission in 30-40% of patients with well compensated liver disease and with hepatitis B virus DNA and hepatitis B e antigen in serum. Features that predict a beneficial response to treatment include high initial serum aminotransferase activities and low levels of circulating viral DNA. Asian patients and children may be less likely to respond to treatment than Caucasian adults. Pre-treatment of patients with a 6-week course of high doses of prednisone may help to increase the response rate to alpha-interferon alone, but this approach should be used only in patients with mild disease and perhaps in patients who have previously failed to respond to alpha-interferon alone. The best approach to treatment of patients with complications of chronic hepatitis B and atypical serological patterns is still uncertain. The efficacy and the side effects of alpha-interferon therapy should be carefully balanced in the decision to treat patients with chronic hepatitis B. Future studies should focus upon the use of newer antiviral agents alone or in combination with alpha-interferon.
A parallel levenberg-marquardt algorithm

This paper describes a parallel Levenberg-Marquardt algorithm that has been implemented as part of a larger system to support the kinetic modeling of polymer chemistry. The Levenberg-Marquardt algorithm finds a local minimum of a function by varying parameters of the function. The modeling system uses the algorithm to optimize the values of constants that describe the rate at which reactions proceed in a model of the chemical reaction. We present a detailed description of the Levenberg-Marquardt algorithm, and describe three levels of parallelization enabled by our algorithm. The performance and precision of our algorithm is compared to that of the IMSL package's implementation of the algorithm, using two models developed by the polymer chemistry research group at Purdue. Our experimental results show increased precision of the final result relative to the IMSL implementation. We also show good scaling with increased numbers of processors, compared to both a sequential version of our algorithm and against the IMSL implementation.
Higgs triplets, decoupling, and precision measurements

Electroweak precision data has been extensively used to constrain models containing physics beyond that of the standard model. When the model contains Higgs scalars in representations other than SU(2) singlets or doublets, and hence {rho}{ne}1 at tree level, a correct renormalization scheme requires more inputs than the three needed for the standard model. We discuss the connection between the renormalization of models with Higgs triplets and the decoupling properties of the models as the mass scale for the scalar triplet field becomes much larger than the electroweak scale. The requirements of perturbativity of the couplings and agreement with electroweak data place strong restrictions on models with Higgs triplets. Our results have important implications for Little Higgs type models and other models with {rho}{ne}1 at tree level.
A Model-based Simulation Approach to Error Analysis of IT Services

Utility computing environments provide on-demand IT services to customers. Such environments are dynamic in nature and continuously adapt to changes in requirements and system state. Errors are an important category of environment state changes as such environments consist of a large number of components, and hence, are subject to errors. In this paper, we design and implement a model-based simulation framework that leverages information about existing service components and their interactions, and provides concrete service behavior in presence of a variety of errors. To evaluate the framework, experiments are conducted on a virtualized blade-server based environment. Results show that the framework is effective and practical in analyzing error impacts on IT services.
The RNA-binding protein Fus directs translation of localized mRNAs in APC-RNP granules

RNA localization pathways direct numerous mRNAs to distinct subcellular regions and affect many physiological processes. In one such pathway the tumor-suppressor protein adenomatous polyposis coli (APC) targets RNAs to cell protrusions, forming APC-containing ribonucleoprotein complexes (APC-RNPs). Here, we show that APC-RNPs associate with the RNA-binding protein Fus/TLS (fused in sarcoma/translocated in liposarcoma). Fus is not required for APC-RNP localization but is required for efficient translation of associated transcripts. Labeling of newly synthesized proteins revealed that Fus promotes translation preferentially within protrusions. Mutations in Fus cause amyotrophic lateral sclerosis (ALS) and the mutant protein forms inclusions that appear to correspond to stress granules. We show that overexpression or mutation of Fus results in formation of granules, which preferentially recruit APC-RNPs. Remarkably, these granules are not translationally silent. Instead, APC-RNP transcripts are translated within cytoplasmic Fus granules. These results unexpectedly show that translation can occur within stress-like granules. Importantly, they identify a new local function for cytoplasmic Fus with implications for ALS pathology.
American anti-feminist women: Comparing the rhetoric of opponents of the equal rights amendment with that of opponents of women's suffrage

Abstract This paper examines the rhetoric of American women opponents of the Suffrage Amendment 1890 to 1919 and of the Equal Rights Amendment 1970 to 1984. Basic to the rhetoric of those opponents is a belief that men and women are so different from each other that they must be treated differently under the law.
Ocean Wave Earth Diffraction Antenna (OWEDA)

The physical objective is to create, for a time span of about an hour, an antenna reflector with an equivalent aperture diameter of about 300 kilometers, as shown in the last part of the introduction. To do this with the convex ocean surface requires use of ocean surface waves. The oweda system determines the surface wave source for a given reflectivity (from a floor slide to ship wakes). The most useful part of the oweda system is coordination of highly data intensive post processing issues involved with transient structural analysis. Transient analysis automation tends to hide details and provide too much data. OWEDA performs calculations and accumulate statistics during the analysis of the data so that extra storage is not necessary. The owedaState.c report takes far less space than one time step of data, S(n) equals (Theta) (n) and the operations run in tandem, T(n) equals (Theta) (n). The time complexity analysis shows how loose bounds on some processes can be overcome by tight bounds on others for an overall tight time complexity bound on the algorithm.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Electrical degradation of fiberglass distribution line pole

This paper presents the results of experiments conducted on fiberglass distribution line pole. First, the critical flashover (CFO) voltage of the fiberglass distribution line pole and its combination with polymer and porcelain insulators is given. Then, the data obtained from the study performed on accelerated aging of fiberglass distribution line poles are presented, followed by a discussion of the results
On matrix cracking in fiber reinforced ceramics

Abstract This paper addresses critical stress at the propagation of a fiber-bridged matrix crack of arbitrary length in fiber-reinforced brittle matrix composites. The formulation of the problem follows the approach adopted earlier by Marshall, Cox and Evans, but a new shear-lag model that accounts for the matrix shear deformation above the slipping region is used here to derive the relationship between the crack opening displacement and the crack surface closure traction. The inclusion of the matrix shear deformation above the slipping region significantly affects the calculated crack tip stress intensity factor and the prediction of the critical stress at the propagation of the crack. Illustrative examples are cited using three available composite systems of SiC-borosilicate, C-borosilicate and Nicalon-lithium-aluminosilicate (LAS).
The selection and utilization of metabolic analogs for nucleic acid synthesis.

Abstract The kinetics of incorporation of uracil and its metabolic analog, 5-fluorouracil, into yeast RNA has been studied. Three separate selection processes have been observed. Accumulation into a water-soluble pool is competitive for the two compounds. A strong preference for exogenous uracil was found in the internal (nucleotide) pool. Transfer of material from this pool into RNA is associated with a third, weak selection for the natural compound. Distribution of the competitors was identical in the non-particulate and ribosomal RNA. Cells grown in 5-fluorouracil synthesize very little ribosomal RNA, while large quantities of non-sedimentable nucleic acid accumulate.
Technology and Applications of BlueGene Supercomputer and Cell Broadband Engine

This paper gives an overview of the technologies and applications of the BlueGene supercomputer and the Cell Broadband Engine. BlueGene/L consists of thousands of low power PowerPC-based ASICs and occupies the number one position in the top 500 supercomputer list with 360 Teraflops of peak performance using 65,536 compute nodes. The Cell Broadband Engine is 9 core processors, with one PowerPC core and 8 SPE cores. Each Cell BE attains over 200 Gigaflops of peak performance when running at 3.2 GHz. In contrast to complicated high-frequency unicore processors, BlueGene and Cell BE processor use multiprocessor approaches and attain high performance per Watt. These systems will clearly have influence on future microprocessor designs.
Structure of the genes encoding the CD19 antigen of human and mouse B lymphocytes.

CD19 is a B lymphocyte cell-surface marker that is expressed early during pre-B-cell differentiation with expression persisting until terminal differentiation into palsma cells. CD19 is a member of Ig gnee superfamily with two extreacellular Ig-like domains separated amino acid cytoplasmic domain. In this study, Southern blot analysis revelaed that the human and mouse CD19 genes were compact single copy genes. Both the human and mouse CD19 genes were isolated and the nucleotide sequences flanking each exon were determined. Both genes were composed of 15 exons and spanned ∼8 kilobases (kb) of DNA in human and ∼6 kb in mouse. The positions of exon-intron boundaries were identical between human and mouse and correlated with the putative functional domains of the CD19 protein. The 200 bp region 5′ of the putative translation initiation AUG codon as well conserved in sequence between human and mouse and contained potential trasncription regulatory elements. In addition, the 3′ untranslated regions (UT) of the CD19 genes following the termination codon were conservedf in sequence. The high level conservation of nucleotide sequences between species in all exons and 5′ and 3′ UT suggests that expression of the CD19 gene may be regulated in a similar fashion in human and mouse.
SPECTROSCOPIC AND SCATTERING INVESTIGATION OF ISOPOLY-MOLYBDATE AND TUNGSTATE SOLUTIONS

Detailed spectroscopic and scattering investigations of isopoly-molybdate and -tungstate solutions as a function of concentration and pH were made. From scattering results the apparent molecular weights were determined as a function of time and concentration. We find that the results agree with the aggregation scheme of simple + hepta + octa + (Mo,O,,A -8 + protonated polymeric species, for molybdate solutions. Tungstate solutions aggregate according to simple - Y-polytungstate - paratungstate-A - paratungstate-B - Ik-metatungstate. The molybdate solutions ex- hibited very rapid equilibration, but the tungstate solutions required several days to reach equilibrium. From the discrete changes in the Raman spectra of both systems we find that the formation of isopoly anions is not a continuous process and that only certain species are present in solution. Our results do not rule out the formation of significant quantities of the octamolybdate anion as suggested by previous investigators.
The monte carlo database system: Stochastic analysis close to the data

The application of stochastic models and analysis techniques to large datasets is now commonplace. Unfortunately, in practice this usually means extracting data from a database system into an external tool (such as SAS, R, Arena, or Matlab), and then running the analysis there. This extract-and-model paradigm is typically error-prone, slow, does not support fine-grained modeling, and discourages what-if and sensitivity analyses.In this article we describe MCDB, a database system that permits a wide spectrum of stochastic models to be used in conjunction with the data stored in a large database, without ever extracting the data. MCDB facilitates in-database execution of tasks such as risk assessment, prediction, and imputation of missing data, as well as management of errors due to data integration, information extraction, and privacy-preserving data anonymization. MCDB allows a user to define “random” relations whose contents are determined by stochastic models. The models can then be queried using standard SQL. Monte Carlo techniques are used to analyze the probability distribution of the result of an SQL query over random relations. Novel “tuple-bundle” processing techniques can effectively control the Monte Carlo overhead, as shown in our experiments.
Design and application of a versatile triple‐laser cell and chromosome sorter

A high-resolution triple-laser sorter was designed and constructed to provide flexible switchover and high-resolution sorting of cells or chromosomes with any combination of one, two, or three lasers. These features provide a central facility instrument that currently serves multiple users and analyzes different stain combinations with minimal switchover effort between experiments. Improved optics and mounts that focus the three laser beams independently are able to resolve beads and chromosomes better than our previously reported dual-laser sorter. An improved signal collection unit with electronically controlled reference positions can be focused more quickly and precisely for any signal combination. A removable dye laser extends the range of usable fluorochrome labels. A rapid sheath switchover permits sorting of sterile cells and sterile chromosomes sequentially without additional sterilization or reservoir sheath change. Improved dual-laser chromosome resolution is at least as good, analyzing 8,000 chromosomes/s, compared to the previous dual-laser bench at 2,000/s. Stimulated and unstimulated peripheral blood lymphocytes were analyzed according to simultaneous measurements of cell surface receptors labeled with a fluoresceinated neuropeptide and a Texas red-labeled antibody as well as DNA content during the cell cycle. These results demonstrate the broad range of potential applications of this triple-laser system.
Implementation of Marginal Bayesian Estimation with Four-Parameter Beta Prior Distributions:

Item parameter estimation for the threeparameter logistic model (3PLM) is sometimes problematic. The estimation algorithm of the 3PLM maximum likelihood estimation procedure often fails, which results in invalid parameter estimates. A procedure based on the marginal Bayesian estimation method introduced by Bock & Aitkin (1981), Swaminathan & Gifford (1985, 1986), and Mislevy & Bock (1990) is proposed here to improve the item parameter estimates for the 3PLM. Four-parameter beta distributions are used as prior distributions for estimating item parameters. A computer simulation study suggested that implementing the marginal Bayesian estimation algorithm with four-parameter beta prior distributions and then updating the priors with empirical means of the updated intermediate estimates can improve item parameter estimation when accurate prior information about the unknown parameters is not available.
A new method to predict unsteady aeroelastic behavior

A new method for predicting subsonic flutter and static deflections, including divergence, has been developed. The present method accounts for aspect ratio and, in the case of flutter, static deflections. The angle of attack is limited only by the occurrence of stall or vortex bursting near the wing. The innovation in the present method is to integrate simultaneously and interactively the equations of motion of the structure and the flowfield. The present approach employs an iterative scheme based on the predictor-corrector method. The general unsteady vortex-lattice method (UVLM) is used to predict the aerodynamic loads. Because the UVLM predicts the wakes as part of the solution, the history of the motion is taken into account; hysteresis is predicted. The deflection (for both bending and torsion) is expressed as an expansion in terms of the free-vibration modes. The time-dependent coefficients in these expansions serve as the generalized coordinates. Numerical examples illustrating the calculation of static deflections and transient dynamic responses above and below the flutter boundary are included.
Dog bites man: A defence of modal realism

(1989). Dog bites man: A defence of modal realism. Australasian Journal of Philosophy: Vol. 67, No. 4, pp. 476-478.
High-Bandwidth Solid-State Nanopore Sensors

Nanopores are attractive electrochemical sensors for their single-molecule sensitivity and simple experimental setup. Many of the electronic systems used for nanopore measurements are inherited from electrophysiology applications, and as a result they are primarily optimized for current levels of 50pA or less, at bandwidths below 10kHz. However, state-of-the-art solid-state nanopore sensors now commonly produce signals in the nanoampere range, for which common patch clamp amplifiers are no longer ideal. We present a new experimental platform which integrates a custom CMOS preamplifier with nanopores in thin silicon nitride membranes. The low parasitic capacitance of the integrated platform reduces noise at high frequencies, allowing nanopore measurements at finer temporal resolution than supported by popular instruments. We demonstrate the viability of this system with high-bandwidth electrical recordings of the passage of short DNA molecules through nanopores. This new platform will improve the signal-to-noise ratios of nanopore sensors, enabling further single-molecule studies of fast biophysical processes.
A hexane fraction of American ginseng suppresses mouse colitis and associated colon cancer: anti-inflammatory and proapoptotic mechanisms.

Ulcerative colitis is a chronic inflammatory condition associated with a high colon cancer risk. We have previously reported that American ginseng extract significantly reduced the inflammatory parameters of chemically induced colitis. The aim of this study was to further delineate the components of American ginseng that suppress colitis and prevent colon cancer. Among five different fractions of American ginseng (butanol, hexane, ethylacetate, dichloromethane, and water), a hexane fraction has particularly potent antioxidant and proapoptotic properties. The effects of this fraction were shown in a mouse macrophage cell line (ANA-1 cells), in a human lymphoblastoid cell line (TK6), and in an ex vivo model (CD4+/CD25− primary effector T cells). A key in vivo finding was that compared with the whole American ginseng extract, the hexane fraction of American ginseng was more potent in treating colitis in a dextran sodium sulfate (DSS) mouse model, as well as suppressing azoxymethane/DSS-induced colon cancer. Furthermore, terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling (TUNEL) labeling of inflammatory cells within the colonic mesenteric lymph nodes was elevated in mice consuming DSS + the hexane fraction of American ginseng. Results are consistent with our in vitro data and with the hypothesis that the hexane fraction of American ginseng has anti-inflammatory properties and drives inflammatory cell apoptosis in vivo , providing a mechanism by which this fraction protects from colitis in this DSS mouse model. This study moves us closer to understanding the molecular components of American ginseng that suppress colitis and prevent colon cancer associated with colitis. Cancer Prev Res; 5(4); 685–96. ©2012 AACR .
A Model For the Effects Of Point-Source Emission Of Aerosols On Groundwater Systems

The effect of natural aerosols on groundwater chemistry is widely accepted, but the effects of anthropogenic aerosol emissions have received relatively little study. This sensitivity analysis examines the factors most significantly influencing the concentration of aerosols in groundwater. Processes include aerosol dispersion from a point source, deposition on the land surface , transport through the unsaturated zone, and mixing with underlying groundwater. The composite simulation model integrates well-documented models for the atmospheric, unsaturated-zone, and saturated-zone systems; models were chosen which could use the most readily obtainable or estimated input parameters. The analysis indicates that point-source aerosol contaminants possess a significant potential to affect aquifer water quality adversely. Furthermore, aerosols may have an impact on background concentrations on a regional scale. The key parameters are the source concentration, net infiltration, transport-velocity distributions in the unsaturated zone, and depth of the water table. We surmise that instances where groundwater contaminant dispersal greatly exceeds predicted travel times could be the result of aerosol contamination and not underestimations of seepage velocities or hydrodynamic dispersion. Aerosol contamination of groundwater should not be dismissed a priori.
Immunohistochemical analysis of dermal mononuclear cell infiltrates in cutaneous lupus erythematosus, polymorphous light eruption, lymphocytic infiltration of Jessner, and cutaneous lymphoid hyperplasia: a comparative differential study.

Cutaneous lupus erythematosus (LE), polymorphous light-eruption (PMLE), lymphocytic infiltration of Jessner (LIJ), and cutaneous lymphoid hyperplasia (CLH) are often difficult to differentiate from ok- another by light microscopic examination. We conducted an immunohistochemical analysis of the mononuclear cell infiltrates in 13 LE, 12 PMLE, 10 LIJ, and 13 CLH with various antibodies. Antibodies L26, UCHL1, and S100 achieved statistically significant differences among the lour diseases, but because of the overlaps in the number of UCHL1 (+) T cells and S100 protein (+) cells in individual cases, these two antibodies were not useful. Only (11,11 could be distinguished from LE, PMLE, and LIJ by a greater number of CD20(+) B cells. The latter three' conditions could not be differentiated. Contrary to previous reports, plasmacyloid-monocytes were not found to be increased in LIJ for the differentiation of the latter from LE and PMLE. Our results support the conclusion that CLH is a reactive lymphoid hyperplastic process with proliferation of both ft and T cells, whereas the T cell was the predominant cell type in the infiltrates of LE, PMLE, and LIJ, indicating that they were related to T cell disorders. The histiocyte was only a minor component cell. The plasmacytoid monocyle in general was not significantly present in all four conditions, but relatively more plasmacytoid monocytes were present in CLH.
TGF-β1 pretreatment impairs the allostimulatory function of human bone marrow-derived antigen-presenting cells for both naive and primed T cells

Transforming growth factor-beta (TGF-beta) exhibits strong antiproliferative effects upon lymphocytes and inhibits many of the effector functions of activated immune cells. However, its influence on the inductive phase of immune responses, and in particular its effect on antigen-presenting cells (APC), has not been well studied. In this investigation, we examined the influence of human TGF-beta 1 on the antigen-presenting function of human bone marrow (BM)-derived APC propagated in liquid culture for 11-17 days in response to granulocyte/macrophage colony-stimulating factor (GM-CSF). These cells were predominantly macrophages, accompanied by a minor population of dendritic cells. TGF-beta 1 had no effect upon the allostimulatory function of vertebral body whole BM cells cultured for 3-5 days in GM-CSF. However, it markedly reduced the allostimulatory capacity of BM-derived APC exposed to the cytokine for the last 3 days of culture. This inhibitory action could not be ascribed to cytokine 'carry-over', or to any consistent changes in the expression of cell surface molecules implicated in antigen presentation (HLA-DR), intercellular adhesion (ICAM-1; CD54), or costimulatory activity (B7-1; CD80). Mechanisms that may underlie the inhibitory action of TGF-beta on APC function and the immunologic and possible clinical implications of the findings are discussed.
Single-center experience in pediatric renal transplantation using thymoglobulin induction and steroid minimization.

Our center has offered thymoglobulin induction with steroid minimization to our pediatric renal transplant patients for the last 10 yr. Steroid minimization or avoidance has shown favorable results in survival, kidney function, and growth in previous studies of pediatric patients. We report our experience with this protocol over the past 10 yr with respect to patient/graft survival, acute rejection episodes, renal function, linear growth, bone density, cardiovascular risk factors, and opportunistic infections. A retrospective chart review was performed for pediatric renal transplant patients on the steroid-minimized protocol between January 2002 and December 2011 on an intention to treat basis. Patient demographics, height, weight, serum creatinine, iGFR, biopsies, and survival data were collected. Height and weight z-scores were calculated with EpiInfo 7, using the CDC 2000 growth charts. Survival was calculated using Kaplan-Meier analysis. eGFR was calculated using the original and modified Schwartz equations. Forty-four pediatric patients were identified, aged 13 months to 19 yr. Five-yr survival was 95.5% for males and 94.4% for females. Only five patients had biopsy-proven ACR, two of which were at more than 12 months post-transplantation. Height delta z-scores from transplant to one, three, and five yr were 0.34, 0.38, and 0.79, respectively. Weight delta z-scores from transplant to one, three, and five yr were 0.87, 0.79, and 0.84, respectively. Mean original Schwartz eGFR was 84.3 ± 15.8 mL/min/1.73 m(2) , modified Schwartz eGFR was 59.3 ± 11.5 mL/min/1.73 m(2) , and iGFR was 64.2 ± 8.5 mL/min/1.73 m(2) at three yr. Of 18 subjects who had a bone density exam, none had a z-score less than -2 on DEXA exam at one-yr post-transplantation. Fifty-one percent of patients were on antihypertensives at the time of transplant compared with 43% at one-yr post-transplantation. Three yr post-transplantation, the average LDL was <100 mg/dL, and average total cholesterol was <200 mg/dL. There were no clinical episodes of EBV or CMV infection. A steroid-minimized protocol with thymoglobulin induction is safe and provides favorable improvement in linear growth, stable graft function, stable or improved cardiovascular risk factors, and normal bone density in pediatric renal transplant patients.
Design Of A Special-Purpose Computer For Locating Targets Within An Image

Starloc (Sandia TARget LOcation Computer) is a special-purpose computer designed for target location in an image. It is based on a generalized correlation filter algorithm. Correlation of the input image and a small number (10-20) of specially-designed filter kernels is performed in the Fourier domain. The correlation of the input image with the filter set produces an encoding at each input image pixel location; targets are located at pixels with specific codes. This target signature is not sensitive to target variations such as rotation, range, brightness, and angle of view. Starloc is now under development and when completed will process two 256 pixel by 256 pixel input images per second. Starloc's basic architecture consists of ten pipelined processing stages (eight for Fast Fourier Transform operations and two for pixel by pixel operations) arranged in a ring-like structure. Within each stage are a controller, image memory, address generator, and register file with parallel floating-point processors. Starloc is designed to be fault tolerant by including two hot standby stages that can be switched into the data path when other stages fail and by incorporating a comprehensive set of error checkers. Using currently available floating-point processors, Starloc will run at a sustained rate of 188 MFLOPS (million floating-point operations per second). At this rate, it is performing 36 complex 256 pixel by 256 pixel two-dimensional Fast Fourier Transforms per second.