cssi/SciSciGPT-SciSciNet huggingface dataset:
Chemical kinetics parameters and model validation for the gasification of PCEA nuclear graphite

A series of gasification experiments, using two right cylinder specimens (� 12.7 � 25.4 mm and 25.4 � 25.4 mm) of PCEA nuclear graphite in ambient airflow, measured the total gasification flux at weight losses up to 41.5% and temperatures (893–1015 K) characteristics of those for in-pores gasification Mode (a) and in-pores diffusion-limited Mode (b). The chemical kinetics parameters for the gasification of PCEA graphite are determined using a multi-parameters optimization algorithm from the measurements of the total gasification rate and transient weight loss in experiments. These parameters are: (i) the pre-exponential rate coefficients and the Gaussian distributions and values of specific activation energies for adsorption of oxygen and desorption of CO gas; (ii) the specific activation energy and pre-exponential rate coefficient for the breakup of stable un-dissociated C(O2) oxygen radicals to form stable (CO) complexes; (iii) the specific activation energy and pre-exponential coefficient for desorption of CO2 gas and; (iv) the initial surface area of reactive free sites per unit mass. This area is consistently 13.5% higher than that for nuclear graphite grades of NBG-25 and IG-110 and decreases inversely proportional with the square root of the initial mass of the graphite specimens in the experiments. Experimental measurements successfully validate the chemical-reactions kinetics model that calculates continuous Arrhenius curves of the total gasification flux and the production rates of CO and CO2 gases. The model results at different total weight losses agree well with measurements and expand beyond the temperatures in the experiments to the diffusion-limited mode of gasification. Also calculated are the production rates of CO and CO2 gases and their relative contributions to the total gasification rate in the experiments as functions of temperature, for total weight losses of 5% and 10%. Published by Elsevier B.V.
The Michael Jackson Fly

Although most of us are more comfortable walking forward, in part because we can see where we are going, people also have the capacity to walk, and even run, in a backward direction. This skill comes in handy when we get stuck in tight dead-end spaces and is even a trendy exercise routine for some ( 1 ). Perhaps most famously, Michael Jackson immortalized the move in his iconic moonwalker dance. Not surprisingly, the capacity for backward locomotion is not limited to humans and now, thanks to elegant experiments carried out in the fruit fly by Bidaye et al. and reported on page 97 of this issue ( 2 ), we have some understanding of how animals choose between forward and backward locomotion.
Ion-Ion Mutual Neutralization Cross Sections Measured by a Superimposed Beam Technique. II. O 2 + + O 2 − , O 2 + + NO 2 − , and NO + + NO 2 −

Two-body ion-ion neutralization cross sections $Q$ have been measured for ${\mathrm{NO}}^{+}$ + ${\mathrm{NO}}_{2}^{\ensuremath{-}}$ and ${\mathrm{O}}_{2}^{+}$ + ${\mathrm{NO}}_{2}^{\ensuremath{-}}$ and remeasured for ${\mathrm{O}}_{2}^{+}$ + ${\mathrm{O}}_{2}^{\ensuremath{-}}$. Using a superimposed-beams method, a range of barycentric energies between 0. 15 and 200 eV was covered. The product ${v}_{r}Q$ behaved somewhat similarly for all reactants when plotted against the relative speed ${v}_{r}$. For relative energies above 3 eV, ${v}_{r}Q$ varies slowly and is of a magnitude of ${10}^{\ensuremath{-}7}$ ${\mathrm{cm}}^{3}$/sec or greater. Below about 3 eV, however, ${v}_{r}Q$ begins to increase rather rapidly with decreasing energy, approaching the expected ${v}_{r}^{\ensuremath{-}1}$ dependence. The low-energy data have been fitted to four-term polynomials in powers of ${v}_{r}$. In this form the data can be extrapolated to the thermal range and rate constants obtained. Reaction rates (300 \ifmmode^\circ\else\textdegree\fi{}K) are given for the above reactants, and also for ${\mathrm{H}}^{+}$ + ${\mathrm{H}}^{\ensuremath{-}}$, ${\mathrm{O}}^{+}$ + ${\mathrm{O}}^{\ensuremath{-}}$, ${\mathrm{N}}^{+}$ + ${\mathrm{O}}^{\ensuremath{-}}$, and ${\mathrm{N}}_{2}^{+}$ + ${\mathrm{O}}_{2}^{\ensuremath{-}}$, which were studied earlier.
Wavelet-based multi-scale coarse graining approach for DNA molecules

In this work, a coarse graining technique based on a multi-scale wavelet projection is proposed for modeling of DNA molecules. Based on the fine scale atomistic response and the Henderson's theorem, the distribution functions between centers of mass of two groups of atoms are employed to obtain the fine scale potential functions. These fine scale potential functions are then homogenized using the multi-scale wavelet projection to yield the coarse-scale effective potential functions between superatoms. Molecular dynamics simulation of DNA molecules under stretching process demonstrates that the results of fine scale model and the proposed coarse grained DNA model are in good agreement. The coarse grained simulation with a significant saving of computation time is shown to be in good agreement with the fine scale simulation. Due to the reduced spatial degrees of freedom and temporal discretization, a computational efficiency of three to four orders of magnitude is achieved in the proposed coarse grained model.
Positive-Grid Characteristics of Triodes

The total emission current in a vacuum tube can be expressed by the familiar space-charge equation. This paper shows theoretically that the ratio of plate current to total current should be a function only of the ratio of grid to plate voltage, and introduces experimental data to show that the function can be represented by a single exponential term. The exponential function is combined with the space-charge equation to obtain an empirical equation for the positive-grid plate-current characteristic. A simple, experimental method of obtaining the constants in this equation is described.
Impact of Parylene-A Encapsulation on ZnO Nanobridge Sensors and Sensitivity Enhancement via Continuous Ultraviolet Illumination

The impact of parylene-A encapsulation and the effect of continuous ultraviolet (UV) exposure on ZnO nanobridge sensor response are investigated. ZnO nanowire (NW) devices are fabricated using a novel method that involves selective growth of ZnO nanobridges between lithographically defined pads of carbonized photoresist (C-PR). We find that a thin coating of parylene-A effectively attenuates the response of NW devices to O2, H2O vapor, and UV illumination. The accessibility of the amine group on parylene-A for chemical functionalization is verified by transforming the amine groups on the surface of the parylene-A coating into aromatic imine groups, followed by UV–Vis absorption. Our results suggest that, in addition to modulating environmental sensitivity and providing protection of the ZnO NWs for liquid- and vapor-phase sensing, the parylene-A encapsulation may also serve as an activation layer for further specific functionalization targeting selective sensing. We also found that the sensitivity and response time of ZnO nanobridge devices to O2 are dramatically improved by continuously exposing the nanobridge devices to UV illumination. Finally, we show that the C-PR directed growth method can also be used to isolate free-standing NW carpet.
Shear migration and chaotic mixing of particle suspensions in a time-periodic lid-driven cavity

This work simulates segregation of noncolloidal particle suspensions in a two dimensional time-periodic flow. Two different mixing protocols having alternating moving boundaries in a cavity known to generate chaotic advection while maintaining a constant energy input rate are applied to each suspension. A diffusive flux model is used to capture the essence of shear-induced migration. In this system, fluid deformation drives both mixing and segregation where the local rheology is a function of particle volume fraction. The impact of migration strength, altered by varying the particle size and bulk volume fraction, and topology, altered by breaking symmetry in the flow when varying the period length, are investigated. As a result of the complex interplay between the flow topology and shear migration, the concentration profile ranges from that representing the underlying topology to that of steady flow in a lid-driven cavity and depends on the parameters mentioned above and the structure produced by the two ...
Alkylating chemotherapy may exert a uniquely deleterious effect upon neo-antigen-targeting anticancer vaccination

Alkylating chemotherapy exerts both antineoplastic and immunostimulatory effects. However, in addition to depleting regulatory T cells (Treg), alkylating agents also mediate a long lasting antiproliferative effect on responder lymphocytes. Our recent findings indicate that this antiproliferative effect profoundly impairs vaccination-induced immune responses, especially in the case of vaccines that target specific tumor-associated neo-antigens that do not require Treg depletion.
Grassmannians of 2-Sided Vector Spaces

Let k ⊂ K be an extension of fields, and let A ⊂ M n (K) be a k-algebra. We study parameter spaces of m-dimensional subspaces of K n which are invariant under A. The space  A (m, n), whose R-rational points are A-invariant, free rank m summands of R n , is well known. We construct a distinct parameter space,  A (m, n), which is a fiber product of a Grassmannian and the projectivization of a vector space. We then study the intersection  A (m, n) ∩  A (m, n), which we denote by  A (m, n). Under suitable hypotheses on A, we construct affine open subschemes of  A (m, n) and  A (m, n) which cover their K-rational points. We conclude by using  A (m, n),  A (m, n), and  A (m, n) to construct parameter spaces of 2-sided subspaces of 2-sided vector spaces.
Expression and induction of secretory phospholipase A2 group IB in brain.

Secretory phospholipases A2 (sPLA2) form a diverse family of enzymes involved in physiologicand pathologic processes. Common among all sPLA2 is the ability to cleave acyl groups of phospholipids at 2C of the glycerol backbone, thereby releasingfatty acid and a lysophospholipid. Several sPLA2 have been cloned and characterized in various tissues.Furthermore, receptors have been identified. In the nervous system sPLA2 groups IIA, IIE, IIF, V, and XII have been identified, and binding sites for sPLA2 group IB (sPLA2-IB) have been found. Here, we report sPLA2-IB in rat and human brain as well as in neurons in primary culture. The distribution of sPLA2-IB seems to be mainly neuronal, with the highest abundance occurring in the cerebral cortex and hippocampus. We also find that genes encoding sPLA2-IB are induced by kainic acid and by electroshock-induced convulsions.Based on the present results we suggest that sPLA2-IB may be a neuronal intercellular signalling modulator.
Separation sequence synthesis by a predictor based ordered search

A predictor based ordered search procedure is used to scan the graph representing all possible separation sequences for a given multicomponent separation process. The algorithmic procedure is expedited by utilizing an heuristic cost function to obtain lower bound estimates of the cost of separators not yet designed. Considerable reduction in search space occurs. Optimal and near optimal sequences are readily generated.
PREVALENCE AND SEVERITY OF UNDIAGNOSED URINARY INCONTINENCE IN WOMEN

BACKGROUND: Urinary incontinence is a highly prevalent condition in aging women that results in significant morbidity. Less than half of women who suffer from urinary incontinence seek treatment, resulting in a significant proportion of clinically relevant urinary incontinence remaining undiagnosed. Therefore, the purpose of this study was to quantify the prevalence of urinary incontinence in undiagnosed women in a managed care population. METHODS: There were 136,457 women aged 25-80 years enrolled in Kaiser Permanente Northwest who were free of genitourinary diagnoses, including urinary incontinence, who were included in this study. Of the 2118 women who were mailed questionnaires ascertaining information on demographic and urinary incontinence characteristics, 875 completed the survey. A chart review of the 234 women who reported moderate to severe urinary incontinence was performed. RESULTS: The prevalence of undiagnosed urinary incontinence was 53% in the preceding year, and 39% in the preceding week. The prevalence of undiagnosed stress, mixed, and urge incontinence was found to be 18.7%, 12.0%, and 6.8%, respectively. Quality of life was found to significantly decrease with increasing urinary incontinence severity. Of the 234 chart-reviewed women, 5% were found to have physician-documented urinary incontinence. CONCLUSIONS: These results suggest that a significant proportion of women in this managed care population are suffering from urinary incontinence that remains undiagnosed. Efforts should be made to encourage women and physicians to initiate conversations about urinary incontinence symptoms in order to decrease the unnecessary burden of this disease.
Decay of isotropic turbulence: Fixed points and solutions for nonconstant G∼Rλ palinstrophy

A Rλ scaling for the palinstrophy coefficient, G, has been observed in grid turbulence by Antonia et al. [J. Turbulence3, 1 (2002) ]. As a consequence it appears that there exist decay laws other than the self-preserving Taylor-microscale decay of Speziale and Bernard [J. Fluid Mech.241, 645 (1992) ], for which G is constant. Analytic solutions of Ristorcelli [Phys. Fluids15, 3248 (2003) ], for the self-similar Taylor microscale decay, are modified to apply to the G∼Rλ decay. The solution indicates an asymptotic k(t)∼t−1 and a Rt→Rt∞ behavior, as seen in the self-preserving Taylor microscale decay. There are two important differences between the two decays: (1) the fixed point Rt∞ and (2) its rate of approach are substantially smaller for the G∼Rλ decay. It appears that the observation of an asymptotic k(t)→t−1 decay with Rt→const is not a demonstration of Taylor microscale self-similarity, and is achieved, at a much later time, in a wider class of flows. This appears to explain the absence of observation...
Some remarks on the numerical evaluation of Fourier and Fourier-Bessel transforms

Abstract Numerous special techniques have been proposed for the numerical evaluation of Fourier transform integrals. Two of these techniques, a method proposed by Broyles based on the trapezoidal rule and one due to Filon, are compared. Also the efficacy of an algorithm proposed by Cooley and Tukey for doing Fourier sums rapidly is discussed and it is shown how this algorithm may be applied to the above Fourier transform techniques. Finally, the numerical evaluation of Fourier-Bessel transforms is discussed.
α6 Integrin Is Regulated with Lens Cell Differentiation by Linkage to the Cytoskeleton and Isoform Switching

Abstract The developing chicken embryo lens provides a unique model for examining the relationship between α6 integrin expression and cell differentiation, since multiple stages of differentiation are expressed concurrently at one stage of development. We demonstrate that α6 integrin is likely to mediate the inductive effects of laminin on lens differentiation as well as to function in a matrix-independent manner along the cell–cell interfaces of the differentiating cortical lens fiber cells. Both α6 isoform expression and its linkage to the cytoskeleton were regulated in a differentiation-specific manner. The association of α6 integrin with the Triton-insoluble cytoskeleton increased as the lens cells differentiated, reaching its highest levels in the cortical fiber region where the lens fiber cells are formed. In this region of the lens α6 integrin was uniquely localized along the cell–cell borders of the differentiating fiber cells, similar to β1. α6β4, the primary transmembrane protein of hemidesmosomes, is also expressed in the lens, but in the absence of hemidesmosomes. Differential expression of α6A and α6B isoforms with lens cell differentiation was seen at both the mRNA and the protein levels. RT-PCR studies demonstrated that α6B was the predominant isoform expressed both early in development, embryonic day 4, and in the epithelial regions of the day 10 embryonic lens. Isoform switching, with α6A now the predominant isoform, occurred in the fiber cell zones. Immunoprecipitation studies showed that α6B, which is characteristic of undifferentiated cells, was expressed by the lens epithelial cells but was dramatically reduced in the lens fiber zones. Expression of α6B began to drop as the cells initiated their differentiation and then dropped precipitously in the cortical fiber zone. In contrast, expression of the α6A isoform remained high until the cells became terminally differentiated. α6A was the predominant isoform expressed in the cortical fiber region. The down-regulation of α6B relative to α6A provides a developmental switch in the process of lens fiber cell differentiation.
Conceptualizing Anthropogenic Change in Fluvial Systems: Drainage Development on the Upper Embarras River, Illinois

While the geomorphic structure of many landscapes is materially molded, shaped and transformed by human practices, it is at the same time experienced and perceived through the mediation of cultural discourse and representation. The objective of this article is twofold: (1) to establish a conceptual framework for integrated analysis of human and geomorphic dimensions of landscape change; and (2) to illustrate the use of this framework in the assessment of a physical system severely affected by human agency. This perspective offers one way in which human agency can be synthesized and integrated into aspects of physical geography— specifically fluvial geomorphology— from both a conceptual and a pragmatic point of view. The upper Embarras River in east central Illinois, used as a case study, has been and continues to be physically affected by the cultural practice of agricultural drainage over the past century and a half.
2 Gb/s all-optical D/A converter

We experimentally demonstrate an all-optical DAC device operating in C-band. This device is based on gain saturation in SOA and converts electrical serial-digital inputs to optical parallel-digits and subsequently to analog-optical output.
Review: evidence for major benefits and harms of antidiabetic agents for diabetes with heart failure is limited.

Source Citation Eurich DT, McAlister FA, Blackburn DF, et al. Benefits and harms of antidiabetic agents in patients with diabetes and heart failure: systematic review. BMJ. 2007;335:458-9. 17761999
Modeling carbon monoxide dehydrogenase/acetyl-CoA synthase (CODH/ACS): a trinuclear nickel complex employing deprotonated amides and bridging thiolates

Carbon monoxide dehydrogenase/acetyl-CoA synthase (CODH/ACS) utilizes a unique Ni-M bime- tallic site in the biosynthesis of acetyl-CoA, where a square-planar Ni ion is coordinated to two thiolates and two deprotonated amides in a Cys-Gly-Cys motif. The identity of M is currently a matter of debate, although both Cu and Ni have been proposed. In an effort to model ACS's unusual active site and to provide insight into the mechanism of acetyl-CoA formation and the role of each of the metals ions, we have prepared and structurally characterized a number of Ni(II)-peptide mimic complexes. The mononuclear complexes Ni(II) N,N'-bis(2-mercaptoethyl)oxamide (1), Ni(II) N,N¢-eth- ylenebis(2-mercaptoacetamide) (2), and Ni(II) N,N¢- ethylenebis(2-mercaptopropionamide) (3) model the Ni(Cys-Gly-Cys) site and can be used as synthons for additional multinuclear complexes. Reaction of 2 with MeI resulted in the alkylation of the sulfur atoms and the formation of Ni(II) N,N¢-ethylenebis(2-methylmer- captoacetamide) (4), demonstrating the nucleophilicity of the terminal alkyl thiolates. Addition of Ni(OAc)2AE4- H2 Ot o3 resulted in the formation of a trinuclear species 5, while 2 crystallizes as an unusual paddlewheel com- plex (6) in the presence of nickel acetate. The difference in reactivity between the similar complexes 2 and 3 highlights the importance of ligand design when syn- thesizing models of ACS. Significantly, 5 maintains the key features observed in the active site of ACS, namely a square-planar Ni coordinated to two deprotonated amides and two thiolates, where the thiolates bridge to a second metal, suggesting that 5 is a reasonable structural model for this unique enzyme.
A variant of particle filtering using historic datasets for tracking complex geospatial phenomena

The paper presents an extension of the particle filtering algorithm that is applicable when an accurate state prediction model cannot be specified but a database of prior state evolution tracks is available. The conventional particle filtering algorithm represents the belief state as a collection of particles, where each particle is a sample from the state space. The particles are updated by applying the state space equations. In the proposed approach, each particle is an instance of a complete state trajectory, drawn from the database of historic state trajectories. An explicit state update model is not required as the trajectory represented by each particle is covers the entire modeling time period. When new observations become available, a proportion of the particles are replaced using trajectories from the database, selected based on distance from the observation. This tracking algorithm is applicable where the state evolves in a complex manner as in the eye of tropical cyclones. The proposed technique is evaluated by tracking selected cyclones from 2005 using a database of cyclone tracks from the previous 25 years.
The conversion of a pure state into a statistical mixture by the linear quantum channel

Abstract A free-space optical communication system is modeled as a linear quantum channel. It is shown that unless the transmitted (input) state is a Glauber coherent state, the received (output) state will be a statistical mixture of states.
From quasisymmetric expansions to Schur expansions via a modified inverse Kostka matrix

Every symmetric function f can be written uniquely as a linear combination of Schur functions, say f=@?"@lx"@ls"@l, and also as a linear combination of fundamental quasisymmetric functions, say f=@?"@ay"@aQ"@a. For many choices of f arising in the theory of Macdonald polynomials and related areas, one knows the quasisymmetric coefficients y"@a and wishes to compute the Schur coefficients x"@l. This paper gives a general combinatorial formula expressing each x"@l as a linear combination of the y"@a's, where each coefficient in this linear combination is +1, -1, or 0. This formula arises by suitably modifying Egecioglu and Remmel's combinatorial interpretation of the inverse Kostka matrix involving special rim-hook tableaux.
Using Animated Probability Plots to Explore the Suitability of Mixture Models with Two Component Distributions

Risk assessors often use different probability plots as a way to assess the fit of a particular distribution or model by comparing the plotted points to a straight line and to obtain estimates of the parameters in parametric distributions or models. When empirical data do not fall in a sufficiently straight line on a probability plot, and when no other single parametric distribution provides an acceptable (graphical) fit to the data, the risk assessor may consider a mixture model with two component distributions. Animated probability plots are a way to visualize the possible behaviors of mixture models with two component distributions. When no single parametric distribution provides an adequate fit to an empirical dataset, animated probability plots can help an analyst pick some plausible mixture models for the data based on their qualitative fit. After using animations during exploratory data analysis, the analyst must then use other statistical tools, including but not limited to: Maximum Likelihood Estimation (MLE) to find the optimal parameters, Goodness of Fit (GoF) tests, and a variety of diagnostic plots to check the adequacy of the fit. Using a specific example with two LogNormal components, we illustrate the use of animated probability plots as a tool for exploring the suitability of a mixture model with two component distributions. Animations work well with other types of probability plots, and they may be extended to analyze mixture models with three or more component distributions.
Designing randomized clinical trials in pediatric neurosurgery.

Objectives Randomized clinical trials provide the best evidence for making treatment decisions and their use in pediatric neurosurgery is increasing. In this paper, we review the basic principles of clinical trial design and discuss the unique challenges in trial design in pediatric neurosurgery.
A model of protein synthesis based on cryo-electron microscopy of the E. coli ribosome

The ribosome is formed by assembly of proteins and nucleic acids, and synthesizes proteins according to genetic instructions in all organisms. Many of the biochemical steps of this fundamental process are known, but a detailed understanding requires a well-defined structural model of the ribosome. Electron microscopy combined with image reconstruction of two-dimensional crystals or single ribosomes has been the most promising technique, but the resolution of the resulting models has been insufficient. Here we report a 25-A reconstruction of the ribosome from Escherichia coli, obtained by combining 4,300 projections of ice-embedded single particles. Our new reconstruction reveals a channel in the small ribosomal subunit and a bifurcating tunnel in the large subunit which may constitute pathways for the incoming message and the nascent polypeptide chain, respectively. Based on these new findings, a three-dimensional model of the basic framework of protein synthesis is presented.
Making Sense of a Globalizing World: Adolescents' Explanatory Frameworks for Poverty

Poverty, like other persistent social problems, has taken on new dimensions and scale due to globalization. This research examined 20 adolescents' explanatory frameworks for global poverty during their participation in an international studies program. International development theories were employed to analyze the range of their responses. The data showed that the students synthesized a range of information to make multifaceted explanations for poverty that included the role of globalization in structuring poverty. These findings suggest that adolescents can develop “synthesizing minds” although all students will not interpret the same information in the same way. Implications for the development of global citizenship in terms of the formation of ethical responsibilities to resolve social problems are also discussed.
Maximizing Investigation Effectiveness in Digital Forensic Cases

Forensic investigation refers to the use of science and technology in the process of investigating a crime scene so as to prove that the perpetrator has committed crime in a court of law. There is a need to collect and investigate evidences that are closely related to the nature of the crime in order to achieve the maximum overall effectiveness. There are two main approaches to crime scene investigation: Sequential and Parallel. In the former case, evidences are first collected from the crime scene and then sent to forensic laboratory for investigation while the latter approach deals with the simultaneous collection and investigation of evidences. In the previous work, sequential scenario involving a single investigator for time critical forensics cases has been solved. This paper deals with the sequential scenario involving multiple investigators. The problem of assigning the evidences to multiple investigators and finding their respective investigation times to maximize the overall effectiveness is formulated using a mixed integer linear programming (MILP) model. While the general problem is NP-hard, a heuristic algorithm is proposed to solve the general problem. Experimental results are shown to evaluate the effectiveness of the heuristic to find either optimal or near-optimal solutions. This paper concludes with a summary of findings and some suggestions for future research.
Beyond advocacy: A review of the active patient concept

In this paper we critically review the active patient concept and place it in a broader social and historical context. We argue that as a reflection of core, Western European values, the active patient concept has not been adequately scrutinized. Very little research has been done that explicitly tests the claims that have been advanced on behalf of this ideal model of the clinician-patient relationship. The research that is available is far from definitive and does not support many of the assertions made by advocates of this approach to patienthood. We urge investigators to substitute theory driven research programs for those motivated by advocacy of a particular ideological stance.
Uniquely strong electronic communication between [Mo2] units linked by dioxolene dianions.

Unprecedented strong electronic communication has been found in dimolybdenum pairs containing quadruply bonded Mo2(DAniF)3+ (DAniF = N,N‘-di-p-anisylformamidinate) units linked by dioxolene (C6X2O42-) anions. The neutral compounds [Mo2(DAniF)3]2(C6X2O4) (1, X = H; 2, X = Cl; 3, X = NO2) and the singly oxidized products {[Mo2(DAniF)3]2(C6X2O4)Mo2}PF6 (4, X = H; 5, X = Cl) have been synthesized and characterized by X-ray crystallography and spectroscopic methods. Unusually short Mo−O distances (∼2.05 A for 1 and 2, and ∼2.01 A for 4 and 5) are implicated in the remarkably strong interaction between [Mo2] units via the linkers. This leads to an extensive charge delocalization in the mixed-valence species, which is mediated by the dioxolene linker, as revealed by the large ΔE1/2 values (763, 795, and 816 mV for 1, 2, and 3, respectively). Additional evidence for the strong electronic coupling is provided by UV−vis, NIR, and EPR spectroscopies and DFT calculations.
Surface acoustic admittance of highly porous open‐cell, elastic foams

This work presents a comprehensive study of the surface acoustic admittance properties of graded sizes of open‐cell foams that are highly porous and elastic. The intrinsic admittance as well as properties of samples of finite depth were predicted and then measured for sound at normal incidence over a frequency range extending from about 35–3500 Hz. The agreement between theory and experiment for a range of mean pore size and volume porosity is excellent. The implications of fibrous structure on the admittance of open‐cell foams is quite evident from the results.
Secretory processes in lymphocyte function.

The secretion of immunoglobulin by plasma cells has been considered a classical example of the “non-regulated” pathway of protein secretion, in which newly synthesized protein is processed by the Golgi, packaged into small vesicles, and immediately secreted without intracellular storage. In the case of lymphokine secretion by T lymphocytes, it is generally not clear whether this non-regulated pathway is also being used, as opposed to the “regulated” pathway which has been proposed to operate in the cytotoxic lymphocyte mechanism. In this case, as in mast cells and endocrine cells, proteins are synthesized and then stored in cytoplasmic granules. The secretion is triggered (regulated) by a membrane receptor-ligand interaction, which for the cytotoxic lymphocytes is part of the target cell binding process. In cytotoxic T lymphocytes, this secretion process can be measured by following the appearance of a granule serine protease in the medium, and it has been shown to be triggered by target cells or by immobilized antibodies which bind the T celt receptor complex. In addition to cytotoxic lymphocytes, cloned T helper cells contain this serine protease in cytoplasmic granules with a low internal pH. Helper lymphocytes secrete this enzyme in response to (1) soluble antigen which has been processed by cells bearing the appropriate MHC antigens; (2) immobilized antibodies against the T cell receptor complex; (3) a combination of phorbol ester and calcium ionophore. Thus in both helper and cytotoxic lymphocytes, the regulated pathway of protein secretion clearly operates after triggering by the T cell antigen receptor.
Cellular and Matrix Contributions to Tissue Construct Stiffness Increase with Cellular Concentration.

The mechanics of bio-artificial tissue constructs result from active and passive contributions of cells and extracellular matrix (ECM). We delineated these for a fibroblast-populated matrix (FPM) consisting of chick embryo fibroblast cells in a type I collagen ECM through mechanical testing, mechanical modeling, and selective biochemical elimination of tissue components. From a series of relaxation tests, we found that contributions to overall tissue mechanics from both cells and ECM increase exponentially with the cell concentration. The force responses in these relaxation tests exhibited a logarithmic decay over the 3600 second test duration. The amplitudes of these responses were nearly linear with the amplitude of the applied stretch. The active component of cellular forces rose dramatically for FPMs containing higher cell concentrations.
ENO-Osher schemes for Euler equations

The combination of the Osher approximate Riemann solver for the Euler equations and various ENO schemes is discussed for one-dimensional flow. The three basic approaches, viz. the ENO scheme using primitive variable reconstruction, either with Cauchy-Kowalewski procedure for time integration or the TVD Runge-Kutta scheme, and the flux-ENO method are tested on different shock tube cases. The shock tube cases were chosen to present a serious challenge to the ENO schemes in order to test their ability to capture flow discontinuities, such as shocks. Also the effect of the ordering of the eigen values, viz. natural or reversed ordering, in the Osher scheme is investigated. The ENO schemes are tested up to fifth order accuracy in space and time. The ENO-Osher scheme using the Cauchy-Kowalewski procedure for time integration is found to be the most accurate and robust compared with the other methods and is also computationally efficient. The tests showed that the ENO schemes perform reasonably well, but have problems in cases where two discontinuities are close together. In that case there are not enough points in the smooth part of the flow to create a non-oscillatory interpolation.
Small-signal modeling of a push-pull current-fed converter

Small-signal models are developed for two circuit versions of the basic push-pull current-fed converter operating in the continuous-mmf modes. The model for each circuit version leads to different small-signal characteristics when the control led-switch duty cycle is above 50% and when it is less than 50%. The models are verified by comparisons with experimentally obtained results.
Untapped resources: can intellectual diversity promote cultural diversity in technology?

Recruiting and retaining a culturally diverse [1] workforce had been identified as a critical problem in technology, for academic, corporate and government organizations. The causes and effects of cultural homogeneity are being documented and becoming better understood, but successful solutions are still hard to find, implement, and measure. In his testimony before the Congressional Blue Ribbon Panel, "Building Engineering and Science Talent", Richard Tapia notes that "A non-supportive environment drives away women and minorities from science, engineering, mathematics at good universities. They migrate towards other majors." [2] Is it possible to "lure" women and minorities back into technical disciplines.A novel approach to this question may be to seek an alternate sense of workplace diversity, namely, intellectual diversity. Recruiting in research tends to focus on certain closely-related fields. If viable candidates can be recruited from non-traditional fields, will this intellectual diversity (i.e. diversity of academic interests) increase cultural diversity?.
Tandem Catalysis by Palladium Nanoclusters Encapsulated in Metal–Organic Frameworks

A bifunctional Zr-MOF catalyst containing palladium nanoclusters (NCs) has been developed. The formation of Pd NCs was confirmed by transmission electron microscopy (TEM) and extended X-ray absorption fine structure (EXAFS). Combining the oxidation activity of Pd NCs and the acetalization activity of the Lewis acid sites in UiO-66-NH2, this catalyst (Pd@UiO-66-NH2) exhibits excellent catalytic activity and selectivity in a one-pot tandem oxidation-acetalization reaction. This catalyst shows 99.9% selectivity to benzaldehyde ethylene acetal in the tandem reaction of benzyl alcohol and ethylene glycol at 99.9% conversion of benzyl alcohol. We also examined various substituted benzyl alcohols and found that alcohols with electron-donating groups showed better conversion and selectivity compared to those with electron-withdrawing groups. We further proved that there was no leaching of active catalytic species during the reaction and the catalyst can be recycled at least five times without significant deactiva...
Structure Prediction-Driven Genetics in Saccharomyces cerevisiae Identifies an Interface Between the t-RPA Proteins Stn1 and Ten1

In Saccharomyces cerevisiae, Cdc13, Stn1, and Ten1 are essential for both chromosome capping and telomere length homeostasis. These three proteins have been proposed to perform their roles at chromosome termini as a telomere-dedicated t-RPA complex, on the basis of several parallels with the conventional RPA complex. In this study, we have used several approaches to test whether a predicted α-helix in the N-terminal domain of the S. cerevisiae Stn1 protein is required for formation of the proposed t-RPA complex, in a manner analogous to the comparable helix in Rpa2. Analysis of a panel of Rpa2–OBStn1 chimeras indicates that whether a chimeric protein contains the Rpa2 or Stn1 version of this α-helix dictates its ability to function in place of Rpa2 or Stn1, respectively. In addition, mutations introduced into a hydrophobic surface of the predicted Stn1 α-helix eliminated association with Ten1. Strikingly, allele-specific suppression of a stn1 mutation in this helix (stn1–L164D) by a ten1 mutation (ten1–D138Y) resulted in a restored Stn1–Ten1 interaction, supporting the identification of a Stn1–Ten1 interface. We conclude that Stn1 interacts with Ten1 through an α-helix, in a manner analogous to the interaction between the comparable subunits of the RPA complex.
Use of cadaveric solvent-dehydrated fascia lata for cystocele repair--preliminary results.

Abstract Objectives. To present a surgical technique in which cadaveric fascia lata is used for cystocele repair. Methods. Twenty-one consecutive women (mean age 67 ± 10 years) with severe cystocele were prospectively enrolled. All patients underwent meticulous clinical and urodynamic preoperative evaluations. Solvent-dehydrated, Tutoplast-processed, cadaveric fascia lata was used for cystocele repair. The fascia was anchored transversally between the bilateral arcus tendineus and the cardinal and uterosacral ligaments. Standard endopelvic plication was performed thereafter as a second layer. Patients with overt or occult sphincteric incontinence underwent concomitant pubovaginal sling (PVS) surgery as well, using the same material. The main outcome measures included recurrent urogenital prolapse, persistent or de novo urinary incontinence (stress or urge), and dyspareunia. Results. Of the 21 patients, 19 underwent concomitant PVS, 3 concomitant vaginal hysterectomy, and 8 posterior colporrhaphy in addition to their cystocele repair. The mean follow-up was 20.1 ± 6.7 months (range 12 to 30). No postoperative complications related to the material or technique occurred. None of the patients developed a recurrent cystocele. Two patients (9%), one of whom underwent concomitant posterior colporrhaphy, developed mild recto-enterocele at 4 to 6 months postoperatively. Six patients underwent concomitant PVS for occult sphincteric incontinence. None developed postoperative stress incontinence. Thirteen other patients underwent concomitant PVS for overt sphincteric incontinence. All but two were stress-continent postoperatively. One half of the patients with preoperative urge or mixed incontinence had persistent urge incontinence postoperatively. None of the patients developed postoperative de novo urge incontinence or dyspareunia. Conclusions. The use of solvent-dehydrated cadaveric fascia lata for cystocele repair, as well as PVS, is associated with encouraging short and medium-term results. Long-term follow-up is needed to evaluate whether these results are durable.
Parasitic cowbirds may defeat host defense by causing rejecters to misimprint on cowbird eggs

Experiments suggest that some hosts that reject parasitic brown-headed cowbird (Molothrus ater) eggs develop egg recognition by imprinting on their own eggs, probably at the first nest naive birds attend. This raises the possibility that parasitism of naive individuals might cause them to mistakenly misimprint on, and accept, cowbird eggs. In an egg-learning experiment designed to cause misimprinting, hosts accepted cowbird eggs when they had laid only 1 egg even though most rejected cowbird eggs when nests had � 2 host eggs. These findings show that cowbirds can cause misimprinting by parasitizing naive hosts. If done oppor- tunistically, misimprinting should become more likely as cowbird abundance increases. In accord with this expectation, simulated brood parasitism showed that 3 host species that usually reject cowbird eggs were more tolerant of cowbird eggs in the Great Plains, where cowbirds reach maximal historic abundance, than in eastern North America where cowbirds are less common. This relation between parasite abundance and host responses is opposite to that found in cuckoo hosts. In addition, these 3 rejecter species had high rates (10.8-30.4%) of natural cowbird parasitism at an Illinois site where cowbirds are extremely, and histor- ically, abundant. These rejecters accepted most cases of researcher-detected parasitism, even though they rarely accept where cowbirds are less common. Despite the potentially high cost resulting from egg rejection, we demonstrate that parasitism of ''rejecters'' can be adaptive for cowbirds particularly when host egg recognition involves learning. Key words: brood parasitism, coevolution, cowbird, egg recognition, imprint, misimprint, Molothrus ater, parasite-host interactions. (Behav Ecol)
The Effects on Union Membership of Race and Immigration Status Focusing on Asian Americans

This study empirically examined the relationship between individuals' race and their union membership status, with particular emphasis on Asian Americans. Using a data set drawn from 14,178 respondents in the March 1996 Current Population Survey, the authors evaluated the predictions of three competing theoretical perspectives-the segmented labor market model, the assimilation model, and the self-protection model-on the union status of Asian Americans. Probit regression results showed that Asians are more likely to join unions than whites. Contrasted to the cases of blacks and whites, immigration-related variables (e.g., length of stay in the United States, naturalized citizens, and foreign nationals) were found to be more significant determinants of union status for Asians than the conventional explanatory variables of union status (e.g., earnings and age). These results are more compatible with the assimilation and the self-protection models than the segmented labor market model.
GPU based real-time instrument tracking with three dimensional ultrasound

Real-time 3D ultrasound can enable new image-guided surgical procedures, but high data rates prohibit the use of traditional tracking techniques. We present a new method based on the modified Radon transform that identifies the axis of instrument shafts as bright patterns in planar projections. Instrument rotation and tip location are then determined using fiducial markers. These techniques are amenable to rapid execution on the current generation of personal computer graphics processor units (GPU). Our GPU implementation detected a surgical instrument in 31 ms, sufficient for real-time tracking at the 26 volumes per second rate of the ultrasound machine. A water tank experiment found instrument tip position errors of less than 0.2 mm, and an in vivo study tracked an instrument inside a beating porcine heart. The tracking results showed good correspondence to the actual movements of the instrument.
Blaming the Victim: A Response to the Proposal that Criminal Law Recognize a General Defense of Contributory Responsibility

There is, perhaps, little that instills greater professional pride in academics than to watch former students go on to thriving careers within their disciplines. The success of one’s students within one’s own professional world seems proof that the pursuit of knowledge is a relay race in which the scholars of each generation pass the batons of the discipline to the next, with the promise that the strides of each will preserve the advances made by the strides of those who ran before. And so it is that I indulge a great deal of selfish pride in commenting upon the recent work of Professor Vera Bergelson, who, as a student of mine at the University of Pennsylvania Law School all too long ago, proved herself very adept at picking up and running with the batons she was handed by her admiring faculty members. The particularly slippery baton that Professor Bergelson so adeptly runs with in her provocative and insightful article, “Victims and Perpetrators: An Argument for Comparative Liability in Criminal Law,” is the chestnut puzzle concerning the criminal law’s refusal to recognize an explicit defense of “contributory responsibility,” as I shall call it, on the part of the victim. Consent is no defense to a crime, it is often said, nor is assumption of risk or contributory negligence. But are these mantras true? asks Professor Bergelson. And if they are true, why would this be? Can a refusal to take account of the victim’s own contributions to the harm for which the
Low Loss Photonic Crystal Waveguide by Elliptical Unit Cell Structure

We report a low loss one-line defect photonic crystal waveguide formed by elliptical unit cell structure. Comparing to its counterpart, circular unit cell photonic crystal waveguide, a loss reduction of 16% is obtained.
Particulate pyrite formation by the Fe3+/HS- reaction in aqueous solutions : effects of solution composition

Microsize particles of pyrite were synthesized by reaction of ferric ions with sulfide ions in aqueous solutions. The reaction products of the synthesis experiments were characterized by X-ray diffraction and electron-optical techniques. The formation of pyrite was affected strongly by the pH and redox potential (Eh) of the working solutions. Pyrite, with a mean particle diameter of 1.5 μm, formed in the pH range 3.6–5.7 at Eh values of ≈0 V (−0.05–0.01 V). The intermediate products of elemental sulfur and FeS (or Fe(HS)+) were identified as essential precursors for pyrite formation. Eh-pH diagrams for the SH2O and FeSH2O systems indicated that the solid species FeS (or the soluble complex Fe(HS)+) and elemental sulfur are both thermodynamically stable under the conditions where pyrite forms. The inability to form pyrite below ≈pH 3.6 is attributed to undersaturation of FeS or the absence of Fe(HS)+. In contrast, the inhibition of pyrite formation above pH ≈ 5.7 is ascribed to the corresponding Eh conditions which make FeS unstable relative to FeOOH. In addition, it was demonstrated that nanoparticles of pyrite could be obtained by lowering the concentrations of Fe3+ and HS− in the early stages of the reaction.