cssi/SciSciGPT-SciSciNet huggingface dataset:
Photonic–plasmonic-coupled nanoantennas for polarization-controlled multispectral nanofocusing

We report on the design and experimental demonstration of array-enhanced nanoantennas for polarization-controlled multispectral nanofocusing in the near-IR spectral range. We design plasmonic double bow-tie nanoantennas-coupled to multiple-periodic nanoparticle arrays to harvest radiation of designed wavelengths from a large spatial area and to focus it into a targeted nanoscale region. Near-field calculations were performed on a gold nanoantenna array using three-dimensional finite difference time domain simulations. Cross-shaped optical nanoantennas were fabricated on glass substrates using electron beam lithography. The optical characterization of the fabricated nanoantennas was performed using second harmonic excitation spectroscopy that demonstrates multiwavelength photonic coupling in good agreement with the antenna modeling. The nanoantenna structures introduced in this Letter provide the ability to focus optical energy into deep subwavelength areas and to address multiple spectral regions with polarization control. Such attributes are highly desirable in optical biosensing, enhanced Raman scattering, and for nonlinear plasmonic applications.
Excitation mechanisms of the e-beam-excited hydrogen laser

We have studied the e-beam--excited molecular-hydrogen laser and the effects of foreign gases, preionization, and cooling the gas. The pressure dependence up to 200 Torr of the laser output and the influence of the impurity gas are described in terms of the energy distribution of the plasma electrons produced in the gas breakdown due to the electric field induced by the fast- rising current pulse. Small additions of argon and nitrogen sharply reduce the laser output, unlike helium which has little effect. Preionization of the gas destroys the lasing action which fully recovers in a time of the order of a millisecond. High-repetition-rate three-level laser action should be possible. Magnetic neutralization of the induced electric field or destruction of inversion would both account for the loss of laser action. The optical gain is increased to more than 300% by liquid-nitrogen cooling. The gain depends on the reduction of Doppler broadening by cooling but must also be understood in terms of the thermal redistribution of the rotational populations. Arguments are given in favor of the direct electron excitation of lasing levels in contrast to excitation involving charged intermediate states. (AIP)
The Relation between Poison Concentration and Survival Time of Roaches injected with Sodium and Potassium Cyanides and Potassium Ferricyanide.

In preceding papers (3, 4, 5) the authors described and analyzed concentration-survival time curves pertaining to roaches injected with arsenicals. The present paper is a study of the relationship between concentration of poison and survival time of large nymphs of the American roach ( Periplaneta americana (L.)) injected quantitatively with sodium cyanide (NaCN) (experiments 1 A, IB, 1 C), potassium cyanide (KCN) (experiment 2), and potassium ferricyanide (K3Fe(CN)6) (experiment 3).
Morphological stability and compositional uniformity of alloy thin films

Abstract Alloy thin films differ from pure materials in two respects: the alloy components may be prone to phase separation and the lattice parameter of the film is generally a function of the alloy composition. Both of these characteristics affect the compositional uniformity of the film, which has implications for the film's mechanical and opto-electronic properties. To explore these phenomena, we present a linear stability analysis of alloy film growth, which accounts for the stresses generated by both film–substrate misfit and compositional nonuniformities. We find that, when compositional stresses are considered, an instability can be present and that this instability is generic to alloy crystal growth. This instability is due to the deposition process, along with compositionally generated stresses, and occurs even in the absence of a film–substrate misfit. We compare our predictions to other related models and to the experimental literature.
SU‐FF‐I‐120: Monte Carlo Simulation of Thin‐Film CdTe Detector Performance for Diagnostic Imaging Applications

Purpose: As a semiconductor material of high atomic number and density, cadmium telluride (CdTe) is highly suitable for direct radiation detection, producing electronic signal in response to incoming x‐rays. Development of thin‐film CdTe deposition techniques in recent years allows for manufacturing of low cost large‐area detectors with superior imaging capabilities and outstanding radiation hardness. We investigate performance on thin‐film CdTe based detector under a range of energies relevant to diagnostic imaging applications. Method and Materials: Our analysis is based on Monte Carlo modeling of the detector performance with MCNP5 package. In order to calculate input spectra for different tungstenanode voltages (kVp) of our clinical simulator unit, we performed series of output measurements required for spectra generation with TungstenAnode Spectral Modeling using Interpolating Polynomials (TASMIP) algorithm. In the next step these generated spectra were ran through a 20 cm water phantom, representing an imaged patient and resulting in a set of primary photon spectra used for detector characterization. Finally, x‐ray beam is set to fall normally at the detector surface through a narrow slit, following a typical setup for line spread function LSF(x) measurement. Results: We calculate frequency‐dependent pre‐sampling detective quantum efficiency DQE(f) for kVp voltages from 40 to 140 kV. Thickness of CdTe was varied from 10 to 1000 microns, covering the range of feasible thin‐film devices. Conclusion: Thin‐film CdTe based detector offers high performance and high spatial resolution due to low signal spreading inherent of direct detection design. In combination with low manufacturing cost of large‐area flat panel device, the detector is decidedly suitable for critical all the diagnostic imaging applications.
Scattering losses in fused silica and CaF 2 for DUV applications

Scattering losses for fused silica were measured over a wide wavelength range (193-800 nm) using different laser sources. The data indicate that scattering centers are smaller than ~ 12 nm, and scattering is consistent with Rayleigh type even at 193 nm. Scattering losses scale with wavelength as 1/λ 4 , and scattering loss at 193 nm was found to be (0.65±0.08)x10 -3 / cm absorption units or (0.15±0.02)% transmission per cm. CaF 2 measurements were completed in the visible wavelength range. The experimental approach for DUV wavelength measurements for CaF 2 is described. Estimated scattering losses at 193 nm are ~0.003% transmission per cm and ~0.006% transmission per cm at 157 nm. Data for CaF 2 indicate deviation from Rayleigh-type scatter.
Thermally Induced Seizure in Journal Bearings During Startup and Transient Flow Disturbance

This paper presents a finite element model that describes the thermomechanical interactions of a journal bearing undergoing thermally induced seizure (TIS). Two Categories of TIS are studied : rite first part deals with occurrence of seizure during the start-up period followed by an investigation of TIS due to a transient flow-disturbance. The paper outlines the finite element modeling and analysis procedure involved in simulating TIS. An extensive set of parametric simulations covering load, speed, shaft radius, operating clearance, bearing length, friction coefficient and thermal expansion coefficient are performed to gain insight into the phenomenon of TIS. A statistical procedure is applied to the simulated results and an empirical relationship is derived. Good agreement between the empirical and published results attests to the capability of the model and its potential for predicting thermally induced seizure during system start up and during flow disturbance.
Review of key trends in HgCdTe materials for IR focal plane arrays

The need for high-performance, low-cost IR focal plane arrays is a constant driver for materials technology improvement. Due to its high quantum efficiency and variable bandgap capability, HgCdTe is the preferred materials systems for a wide range of applications. HgCdTe crystal growth has evolved over the past fifteen years from relatively small (< 10 mm diameter) bulk multigrained ingots to large (approximately 75 mm diameter) epitaxial layers on composite substrates, but issues regarding material quality and producibility remain. Epitaxial techniques are now firmly established as the superior approaches for the growth of large-area, compositionally uniform material. Enabling this trend is the extensive progress in the size and crystalline quality of bulk lattice-matched CdZnTe substrates and the emergence of large-area heteroepitaxial substrates with CdTe and CdZnTe buffer layers on GaAs and Si. Because of the multiple interfaces, defect levels in the latter tend to be about 100 X larger than in bulk substrates; reducing these levels will be a challenge for the near future. In the meantime, bulk substrates will remain in demand for their lower dislocation densities.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Electric Vehicle and the Burden of History

In the late 1890s at the dawn of the automobile era, steam, gasoline and electric cars all competed to become the dominant automotive technology. By the early 1900s the battle was over and internal combustion had won. The author examines the relationship of technology, society and environment to system choice and economic growth in the history of American transportation. The author also discusses the current debates about the social and environmental impacts of the automobile, the introduction of new hybrid vehicles and the efforts to return to electric-powered vehicles.
Recombinant Human Relaxin (rhRLX) Modifies Systemic Arterial Properties in Conscious Rats Irrespective of Gender, but in a Biphasic Fashion

Chronic administration of recombinant human relaxin (rhRLX) to conscious female nonpregnant rats that reaches serum concentrations of 10-30 ng/mL increases cardiac output and reduces systemic arterial load comparable to levels observed in midterm pregnancy. Chronic administration of the hormone to male rats increases cardiac output and reduces systemic arterial load to a similar extent. Short-term or chronic administration of rhRLX to conscious female rats that reaches serum concentrations of approximately 80 ng/mL results in minimal and insignificant changes. We conclude that: (1) rhRLX increases cardiac output and reduces arterial load irrespective of gender, and (2)the rhRLX dose response is biphasic.
Amplification and Electrical Systems for a Double Beam Recording Infra-Red Spectrophotometer

A detection and amplification system for a recording infra-red spectrophotometer has been designed and built around a pin-type thermocouple, 13-cycle chopper, 13-cycle amplifier and synchronous rectifier. The subsequent circuits modulate the rectified output to 60 cycles for operation of a 2-phase servo balance motor and automatic suppression of the wave-length scanning speed whenever a pen servo error exists. An independent circuit employs a tapped potentiometer as an electrical cam to control the monochromator slit width to give relatively constant energy output at seven energy levels. A total of eighteen tubes are employed, with three of them in the 13-cycle amplifier. The first tube is operated at reduced voltage with a floating grid following a 300:1 gain transformer. Special construction of the preamplifier greatly reduces the susceptibility to 60-cycle pick-up over previous amplifiers.
Nominals, facts, and two conceptions of events

My starting point in this paper is some work of Zeno Vendler, who more than once has pointed to linguistic evidence that he claims justifies a philosophical distinction between facts events.' That the distinction is needed I agree, but I believe Vendler has mislocated it. For one thing, the set of grammatical structures he views as designating facts is too broad. Secondly, I shall argue, there are two altogether different ways of conceiving events. On one of these conceptions they are indeed designated by the structures Vendler views as event names. But on the other conception, which is in some ways the more fundamental of the two, the job of naming events is done using structures Vendler mistakes for fact designators. Neither of these ways of conceiving events will prove entirely unfamiliar, and distinguishing them paves the way for a number of valuable insights concerning time and the ontology of change. My chief purpose here, however, will be simply to show that a basis for the distinction in question can be found in the structural features of English. Vendler has also shown that his position on the grammatical constructions used to designate facts and events leads to important claims regarding causality, notably that causes are always facts.2 My conclusions will undermine this result, but I shall not be especially concerned with causes.
Detection of demyelination in multiple sclerosis by analysis of [Formula: see text] relaxation at 7 T.

Multiple sclerosis (MS) is a relatively common cause of inflammatory demyelinating lesions of the central nervous system. In an attempt to detect and characterize ongoing demyelination in MS patient brains, we used a novel magnetic resonance imaging (MRI) technique, involving the fitting of a three-component model to the T2* relaxation behavior at high-field (7 T). This model allowed estimation of the amount of myelin water (and thus indirectly myelin content), axonal water, and interstitial water. In this study, 25 relapsing–remitting MS patients underwent a 7 T MRI from which 12 gadolinium-enhancing lesions, 61 non-enhancing lesions, and their corresponding contralateral normal appearing white matter (NAWM) regions were analyzed. In both enhancing and non-enhancing lesions, the amplitude of myelin water was significantly decreased, and interstitial and axonal water were increased relative to the contralateral NAWM. Longer relaxation time T2* of interstitial and axonal water, and lower frequency shift of axonal water, were also observed in both enhancing and non-enhancing lesions when compared to the contralateral NAWM. No significant difference was found between enhancing lesions and non-enhancing lesions. These findings suggest that the fitting of a three-component model to the T2* decay curve in MS lesions may help to quantify myelin loss.
Research traditions in Malaysia and the West

This research raises a complex of questions about the relationship between the West and its former colonies. Many ex-colonised countries are now emerging as developing or developed economies, yet they are still using the Western accounting systems. We know from the African history that these nations already had in place their own accounting and auditing systems prior to the colonial era. In Africa, for instance, a huge number of merchants continue to use traditional African accounting and auditing methods. This paper seeks to restore the collective memory concerning African accounting for both African scholars and those in the West who are interested in discovering these accounting truths. The same experiences are also relevant for Asian countries.
Thoughts on Sydney Shoemaker’s Physical Realization

This paper discusses in broad terms the metaphysical projects of Sydney Shoemaker’s Physical Realization. Specifically, I examine the effectiveness of Shoemaker’s novel “subset” account of realization for defusing the problem of mental causation, and compare the “subset” account with the standard “second-order” account. Finally, I discuss the physicalist status of the metaphysical worldview presented in Shoemaker’s important new contribution to philosophy of mind and metaphysics.
Responsive electrolytes that inhibit electrochemical energy conversion at elevated temperatures

Energy storage has emerged as a critical challenge due to the increasing demand to utilize energy from intermittent, renewable resources. Furthermore, growing interest in decreasing our dependence on petroleum necessitates the development of safe and efficient energy storage for transportation. Li-ion batteries have emerged as the premier candidate to meet these demands; however, such systems are limited by thermal hazards (runaway reactions, fires, explosions), which become increasingly dangerous in large-format batteries. We have developed an electrolyte system comprising poly(ethylene oxide), an ionic liquid and lithium salt that exhibits an intrinsic mechanism for inhibiting device operation when the temperature increases beyond a given threshold, which is attributed to polymer–ionic liquid phase separation. In the following article, we describe how the thermally activated phase separation causes a decrease in ion conductivity, thereby affecting the concentration of ions at the electrode, in addition to an increase in charge transfer resistance from the formation of a polymer coating on the porous electrode. Such mixtures provide a transformative approach to regulating electrochemical processes, which is necessary to achieve inherently safe operation of large format Li-ion batteries.
TNF-α mediates chemokine and cytokine expression and renal injury in cisplatin nephrotoxicity

The purpose of these studies was to examine the role of cytokines in the pathogenesis of cisplatin nephrotoxicity. Injection of mice with cisplatin (20 mg/kg) led to severe renal failure. The expression of cytokines, chemokines, and ICAM-1 in kidney was measured by ribonuclease protection assays and RT-PCR. We found significant upregulation of TNF-alpha, TGF-beta, RANTES, MIP-2, MCP-1, TCA3, IL-1beta, and ICAM-1 in kidneys from cisplatin-treated animals. In addition, serum, kidney, and urine levels of TNF-alpha measured by ELISA were increased by cisplatin. Inhibitors of TNF-alpha production (GM6001, pentoxifylline) and TNF-alpha Ab's reduced serum and kidney TNF-alpha protein levels and also blunted the cisplatin-induced increases in TNF-alpha, TGF-beta, RANTES, MIP-2, MCP-1, and IL-1beta, but not ICAM-1, mRNA. In addition, the TNF-alpha inhibitors also ameliorated cisplatin-induced renal dysfunction and reduced cisplatin-induced structural damage. Likewise, TNF-alpha-deficient mice were resistant to cisplatin nephrotoxicity. These results indicate cisplatin nephrotoxicity is characterized by activation of proinflammatory cytokines and chemokines. TNF-alpha appears to play a central role in the activation of this cytokine response and also in the pathogenesis of cisplatin renal injury.
Small Spatial Scale Variation in Fish Assemblage Structure in the Vicinity of the Northwestern Gulf of Mexico Hypoxic Zone

Seasonal hypoxia [dissolved oxygen (DO) ≤ 2 mg l−1] occurs over large regions of the northwestern Gulf of Mexico continental shelf during the summer months (June–August) as a result of nutrient enrichment from the Mississippi–Atchafalaya River system. We characterized the community structure of mobile fishes and invertebrates (i.e., nekton) in and around the hypoxic zone using 3 years of bottom trawl and hydrographic data. Species richness and total abundance were lowest in anoxic waters (DO ≤ 1 mg l−1) and increased at intermediate DO levels (2–4 mg l−1). Species were primarily structured as a benthic assemblage dominated by Atlantic croaker (Micropogonias undulatus) and sand and silver seatrout (Cynoscion spp.), and a pelagic assemblage dominated by Atlantic bumper (Chloroscombrus chrysurus). Of the environmental variables examined, bottom DO and distance to the edge of the hypoxic zone were most strongly correlated with assemblage structure, while temperature and depth were important in some years. Hypoxia altered the spatial distribution of both assemblages, but these effects were more severe for the benthic assemblage than for the pelagic assemblage. Brown shrimp, the primary target of the commercial shrimp trawl fishery during the summer, occurred in both assemblages, but was more abundant within the benthic assemblage. Given the similarity of the demersal nekton community described here to that taken as bycatch in the shrimp fishery, our results suggest that hypoxia-induced changes in spatial dynamics have the potential to influence harvest and bycatch interactions in and around the Gulf hypoxic zone.
From Cell Growth to Leaf Growth: III. Kinetics of Leaf Expansion

Plant growth models have, in general, not considered the detailed aspects of cell expansion and cell division. A key benefit gained by considering growth from a cellular perspective is a more thorough understanding of the role of water relations and plant growth. The objective of this research was to simulate leaf expansion in monocots using a model that incorporates cell division and cell expansion. The core of the model is a module that couples cell division and cell expansion. Assumptions are made concerning the arrangement within the leaf of the cells produced by the cell growth module. Inputs to the model include the total water potential external to the cells and the temperature of the cells. The effects of varying these input parameters on the model outputs (leaf length, leaf area, cell number, elongation rate, and meristem dimensions) are studied. The output is fairly sensitive to the water potential inputs and somewhat less sensitive to the temperature input. These sensitivities are discussed in relation to leaf expansion in field-grown maize (Zea mays L.) plants under well-watered and water-limiting conditions. An extension to the model is described wherein a simple mass balance is calculated on the amount of C produced by the mature portion of the leaf and the amount of C used in the expanding portion
The concept of sickness behavior: a brief chronological account of four key discoveries.

Abstract Neurons do not have receptors to detect bacteria or viruses, yet the presence of these microorganisms can cause a sickness behavior syndrome that includes, e.g., fever, anorexia, and lethargy. Because the immune system has receptors capable of detecting these non-cognitive stimuli, how the immune system transmits a message to the brain has been studied to understand why behavior is altered in sick animals. The focus has been on several cytokines secreted by leukocytes; these include interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α). These cytokines are secreted by activated mononuclear phagocytic cells, and numerous studies show that both peripheral and central injection of IL-1β, IL-6, and TNF-α induce sickness behavior. Moreover, these cytokines and their receptors are present in the brain and inhibiting the secretion of cytokines or blocking their receptors in the brain blocks or abrogate the behavioral responses induced by inflammatory stimuli. Because the sickness behavior syndrome modulates the immune system and enhances recovery, the interplay between the immune system and central nervous system is an essential part of the overall host defense against pathogenic microorganisms. The purpose of this brief paper is to provide a chronological description of four critical advances that have led to the current understanding of how the immune system communicates with the brain to induce sickness behavior. Results from several key studies will be discussed, which showed that: (1) sickness behavior is a motivational state; (2) sickness behavior is a well-organized adaptive response to infection; (3) cytokines produced by activated leukocytes induce sickness behavior; and (4) cytokines transmit messages from the periphery to the brain using humoral and neural pathways.
A power law for connectedness of some random graphs at the critical point

We consider P(G is connected) when G is a graph with vertex set Z+ = {1,2, …}, and the edge between i and j is present with probability p(i, j) = min(λ h(i, j), 1) for certain functions h(i, j) homogeneous of degree -1. It is known that there is a critical value λc of λ such that . We show that the probability, at the critical point λc, that n1, and n2 are connected satisfies a power law, in the sense that for n2 ≧ nt ≧ 1 for any δ > 0 and certain constants c1 and c2.
User, robot and automation evaluations in high-throughput biological screening processes

This paper introduces high-throughput screening of biological samples in life sciences, as a domain for analysis of human-robot interaction (HRI) and development of usable human interface design principles. High-throughput screening (HTS) processes involve use of robotics and highly automated analytical measurement devices to transport and chemically evaluate biological compounds for potential use as drug derivatives. Humans act as supervisory controllers in HTS processes by performing test planning and device programming prior to experiments, systems monitoring, and real-time process intervention and error correction to maintain experiment safety and output. Process errors are infrequent but can be costly. Two forms of cognitive task analysis were applied to a highly automated HTS process to address different classes of errors, including goal-directed task analysis to describe critical operator decisions and information requirements and abstraction hierarchy modeling to represent HTS process devices and automation integrated in screening lines. The outcomes of the analyses were used as bases for generating supervisory control interface design recommendations to improve existing system usefulness and usability.
The immunochemistry of sandwich ELISAs—V. The capture antibody performance of polyclonal antibody-enriched fractions prepared by various methods☆

Studies compare the performance of antibody-enriched serum fractions prepared by various methods, when adsorbed on polystyrene microtiter wells as capture antibodies (CAbs) and tested against multivalent antigens. The criteria of performance in the RIA used included antigen capture capacity (AgCC) and the nmol of functional capture sites per microtiter well (CAbt). Affinity purified polyclonal (pAb) and monoclonal antibodies (mAb) were employed as reference CAbs. AgCC was highest for enriched fractions prepared using caprylic acid and a high-pressure SpG affinity column. The performance of capture antibodies is expressed by an equation which was empirically derived and experimentally tested; CAbt x AgCC/ng adsorbed IgG. In terms of this parameter, CAb-enriched fractions prepared with caprylic acid performed best. The data reported also provide insight into solid-phase ligand immunochemistry. Adsorbed polyclonal CAb performed with remarkable homogeneity in percent bound and in Scatchard plots. Values obtained for CAbt from Steward-Petty plots were directly correlated with the length of the LBR of log-log percent bound plots but indicated that less than 10% of the potential capture sites of polyclonal CAbs remained functional after adsorption; mAb showed a more serious loss of activity. The loss of CAbt was a general phenomenon for all preparations tested although relative to their antibody content, certain antibody-enriched fractions retained a higher proportion of CAbt than their affinity-purified counterparts. Comparative studies in which the activity of adsorbed mAb and pAb was compared to the same antibodies immobilized by a non-adsorptive procedure, indicated that adsorbed CAbs also express lower affinity. The studies we report offer a single parameter criterium for comparatively evaluating CAb performance while simultaneously revealing the need to develop immobilization procedures that can preserve CAbt and antibody affinity so that immunoassays with wide dynamic ranges and high AgCC can be developed without waste of antibody.
NT-3 and BDNF protect CNS neurons against metabolic/excitotoxic insults.

Abstract Neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) were recently shown to have biological activity in central neurons. In the present study, NT-3 and BDNF attenuated glucose deprivation-induced neuronal damage dose-dependently in rat hippocampal, septal and cortical cultures. Direct measurements of intraneuronal free calcium levels ([Ca2+]i) and manipulations of calcium inlux demonstrated that NT-3 and BDNF each prevented the elevation of [Ca2+]i that mediated glucose deprivation-induced injury. Studies in cultures depleted of glia indicateda direct action of NT-3 and BDNF on neurons. Neurons pretreated with NT-3 or BDNF for 24 hr were more resistant to glutamate neurotoxicity, and showed attenuated [Ca2+]i responses to glutamate. TrkB (BDNF receptor) and trkC (NT-3 receptor) proteins were present in hippocampal, cortical and septal cultures where they were localied to neuronal cell bodies and neurites. The data demonstrate that NT-3 and BDNF can protect neurons against metabolic and excitotoxic insults, and suggest that these neurotrophins may serve [Ca2+]i-stabilizing and neuroprotective functions in the brain.
Gas/Aerosol Distribution of Formic and Acetic Acids

Data and correlations for evaluating the gas/aerosol equilibrium of formic and acetic acids are developed. The species considered include HCOOH(g), CH3COOH(g), HCOOH(aq), CH3COOH(aq), HCOO−, CH3COO−, HCOONa(s), CH3COONa(s), HCOOK(s), (HCOO)2Ca(s), and (CH3COO)2Ca(s). Based on available thermodynamic data, we show that the gas /aerosol distribution of formic and acetic acids is strongly on the gas-phase side for typical sulfate/ nitrate / ammonium / sodium / chloride / water aerosols and that dissolved formate and acetate have negligible effect on the gas/aerosol equilibrium of the other components.
Heat transfer in particulate flows

Abstract A phenomenological model is developed for particulate flows in pipes. The gas-solid mixture is modeled as a variable density, variable heat capacity fluid with the solid phase contributing to fluctuations in the mean properties of the flow. The momentum and energy equations are developed for the steady-state flow of such a fluid, and when averaged, several new terms appear that emanate from the fluctuation products. Simple diffusivity theory is used to obtain closure equations for the last terms. Finally, the resulting ordinary differential equations are solved and results are obtained for the heat transfer coefficient of the gas-solid mixtures.
Hydrophobic Complexation of Poly(vinyl caprolactam) with Sodium Dodecyl Sulfate and Dodecyltrimethylammonium Bromide in Solution

The interaction of poly(vinyl caprolactam) (PVCAP) with sodium dodecyl sulfate (SDS) and dodecyltrimethylammonium bromide (DTAB) in aqueous solutions has been studied systematically by measuring the phase separation temperature, hydrodynamic radius, pyrene solubility, and surfactant binding isotherms. Both surfactants were observed to elevate the solution cloud point of PVCAP and cause the polymer to undergo a coil to globule transition. This transition occurs at a concentration about 1/10 of the critical micelle concentration (cmc) for SDS in the absence of polymer but at the cmc with DTAB. The results indicate that PVCAP interacts with SDS monomers but only with micelles in the case of DTAB. The phase behavior of the PVCAP/SDS/DTAB ternary system shows that the binding of SDS to PVCAP is reversible on changing the concentration of the free surfactant monomer in solution. Potentiometric titration of PVCAP and measurements of pyrene solubility in its mixtures with surfactants suggest that complexation of ...
High-Tc superconducting NbN films with low particulate density grown at 25 °C using pulsed laser deposition

The growth and characterization of high-Tc NbN films formed on room temperature substrates by pulsed laser deposition is described. The growth was performed at a high laser power density (>5 × 108 W/cm2), where the enhanced reactivity of species in the plume is proposed as the mechanism for increased nitrogen incorporation in films on unheated substrates. The Tcs were 16.2 K on MgO and 13 K on SiNx/Si substrates. In addition to electrical transport measurements, the films were characterized using RBS and x-ray diffraction. The particulate density on films grown at high power density was significantly reduced, which is correlated with the Nb target having a smoother morphology, characteristic of a quenched molten surface layer in the ablated area.
The elastic interaction between a screw dislocation and a spherical inclusion

Abstract Using an extension of a classical technique due to Kelvin, the general solution for the interaction between a spherical inclusion in an infinite medium and any self-equilibrated source of stress outside the inclusion is derived in the form of infinite series involving spherical surface harmonics. This solution is then applied to the special case of the interaction between a screw dislocation and a spherical inclusion. The main features of the interaction are illustrated by examining the Peach-Koehler force per unit length on the dislocation. Expressions for the net force and interaction energy are also found, and it is seen that truncation of these various expansions leads to expressions which agree with existing long-range interaction expressions. The long-range prediction of the net force and energy is seen to be in good agreement with the exact results when the dislocation is sufficiently far from the inclusion. Finally a comparison is made between the spherical inclusion-screw dislocation interaction problem and its two dimensional analogue involving a cylindrical inclusion, and it is shown that there is not good agreement between the distribution of force on the dislocation for these two problems.
Risk Perspectives on Rail Transport of Spent Nuclear Fuel

The US Nuclear Regulatory Commission (NRC) has completed a study of historical rail accidents (from 1975 to 2005) involving hazardous materials and long duration fires in the United States. The study was initiated to determine what types of accidents had actually occurred, and what type of impact those types of accidents could have on the rail transport of spent nuclear fuel. The NRC found that almost 21 billion miles of rail shipments has yielded only a small number of accidents involving hazardous materials, eight of which involved both hazardous materials and long duration fires. The NRC reviewed these eight accidents in detail to determine what types of effects these accidents might have on a spent fuel cask, should one have been involved. The staff determined that the fires witnessed in the accidents studied would not have provided a fully engulfing fire environment as described by the hypothetical accident condition fire in NRC regulations for radioactive material transport found in Title 10 of the Code of Federal Regulations, Part 71, Section 73. This paper will detail the NRC study of these accidents and conclusions regarding effects on transportation casks exposed to the fires that resulted from these accidents.Copyright © 2008 by ASME
Auxin-induced growth of Avena coleoptiles involves two mechanisms with different pH optima.

Although rapid auxin-induced growth of coleoptile sections can persist for at least 18 hours, acid-induced growth lasts for a much shorter period of time. Three theories have been proposed to explain this difference in persistence. To distinguish between these theories, the pH dependence for auxin-induced growth of oat (Avena sativa L.) coleoptiles has been determined early and late in the elongation process. Coleoptile sections from which the outer epidermis was removed to facilitate buffer entry were incubated, with or without 10 micromolar indoleacetic acid, in 20 millimolar buffers at pH 4.5 to 7.0 to maintain a fixed wall pH. During the first 1 to 2 hours after addition of auxin, elongation occurs by acid-induced extension (i.e. the pH optimum is <5 and the elongation varies inversely with the solution pH). Auxin causes no additional elongation because the buffers prevent further changes in wall pH. After 60 to 90 minutes, a second mechanism of auxin-induced growth, whose pH optimum is 5.5 to 6.0, predominates. It is proposed that rapid growth responses to changes in auxin concentration are mediated by auxin-induced changes in wall pH, whereas the prolonged, steady-state growth rate is controlled by a second, auxin-mediated process whose pH optimum is less acidic.
Water transport through plant tissue: the apoplasm and symplasm pathways.

Abstract A detailed quantitative analysis of water flow through the apoplasm and symplasm of plant tissue is presented. The analysis results in two coupled diffusion equations which describe water transport in the two pathways. Various parameters entering the analysis identify the physical properties of the tissue which control the transport process as the resistance to water flow per cell in the two parallel pathways, the resistance per cell between pathways, and the water capacity per cell in the two pathways. Values for the several resistances and water capacities are estimated from available data, and a model problem is solved wherein a sheet of tissue at an initial water potential of — δ bars is immersed in a container of water. The resulting solutions show that depending on the values assigned to the controlling parameters, local water potential equilibrium between each cell and its cell wall may or may not obtain. In the special case of local equilibrium (water potential in the symplasm and apoplasm pathways essentially equal), the transport process can be described by a single diffusion equation which is derived along with an expression for the tissue diffusivity. It is concluded that the weakest link in the analysis is the estimated value for the permeability of the plasmodesma membrane, and that a logical extension of the theory would be to include the effects of a diffusable solute.
Performance Study of PETT VI, a Positron Computed Tomograph with 288 Cesium Fluoride Detectors

The first positron computed tomography system with cesium fluoride scintillation detectors, PETT VI, has been developed. The system provides 7 slice images with 4 detector rings (57 cm). Performances of the system are discussed and clarified based on experimental data. Adoption of CsF detectors decrease the random coincidence rate by achieving a short coincidence timing resolution. The timing resolution of a pair of detector heads is 1.5 nsec FWHM and 3.0 nsec FWTM. After a preliminary timing alignment of 288 detectors, the coincidence window width (2?) of 11 nsec or wiider has yielded maximum coincidence sensitivity, and operation at 5.9 nsec has given 91% of maximum. The full sensitivity for a cyclindrical uniform phantom (20 cm dia × 13 cm) is 354 kcps/microCi/cc/7 slices in a low resolution mode (intrinsic resolution at center is 11.7 mm FWHM). In a high resolution mode (7.1 mm), it is 31% of the full sensitivity. Coincidence rates ratio, [random/(true + scattered)], in the low resolution mode, is 0.16 ? with 5.9 nsec window width inside the phantom images reconstructed without a random correction, where ? is activity density (microCi/cc). The ratio is 1/3 of that obtained when operating at 20 nsec. Scattered coincidence fraction at the center of the phantom images, without the random correction process, is 9% of the [true + scattered].
Dyadic Approximation of double Integrals with Respect to Symmetric Stable Processes

Abstract Recently, Rosinski and Woyczynski have given necessary and sufficient conditions for the existence of the double integral with respect to a symmetric stable process of index α in [1, 2). In their approach the double integral is defined as an iterated Ito-type integral. We show here that it can also be defined as the limit of integrals of step functions and that the two approaches are equivalent. For many purposes this result reduces the study of double integrals to that of quadratic forms in independent stable random variables.
Using amplitude-integrated EEG in neonatal intensive care

The implementation of amplitude-integrated electroencephalography (aEEG) has enhanced the neurological monitoring of critically ill infants. Limited channel leads are applied to the patient and data are displayed in a semilogarithmic, time-compressed scale. Several classifications are currently in use to describe patient tracings, incorporating voltage criteria, pattern recognition, cyclicity, and the presence or absence of seizures. In term neonates, aEEG has been used to determine the prognosis and treatment for those affected by hypoxic-ischemic encephalopathy, seizures, meningitis and even congenital heart disease. Its application as inclusion criteria for therapeutic hypothermia remains controversial. In preterm infants, normative values and patterns corresponding to gestational age are being established. As these standards emerge, the predictive value of aEEG increases, especially in the setting of preterm brain injury and intraventricular hemorrhage. The sensitivity and specificity of aEEG are enhanced by the display of a simultaneous raw EEG, which aids interpretation. Caution must be taken when using and interpreting this tool in conjunction with certain medications and in the setting of less experienced staff. Continuing efforts at developing software that can aid seizure detection and background classification will enhance the bedside utility of this tool.
Synaptic depression: a key player in the cortical balancing act

What regulates the balance between cortical excitation and inhibition? Galaretta and Hestrin show that prolonged firing induces a much stronger depression at excitatory synapses than at inhibitory ones, making the network more stable and less prone to runaway excitation.
Catalytic Hydrodechlorination of 1,1-Dichlorotetrafluoroethane by Pd/Al2O3

Palladium supported on {gamma}-alumina displays high activity for the hydrodechlorination of 1,1-dichlorotetrafluoroethane. High H{sub 2} partial pressures are needed to avoid deactivation, and steady state is obtained after {approximately}5 h time on stream. Under these conditions (H{sub 2}/CFC feed ratio = 20) the reaction is zero order in H{sub 2} partial pressure and positive (0.65) order in 1,1-dichlorotetrafluoroethane partial pressure. 1-chloro-1,2,2,2-tetrafluoroethane, and 1,1,1-trifluoroethane, with approximately 85% selectivity toward the desired CF{sub 3}CFH{sub 2}. The apparent activation energies associated with the formation of each product range from 52 to 68 kJ/mol. All three major products have a nonzero rate of formation in the limit of zero conversion, the implication of which is that all are primary products. The kinetics results are consistent with a reaction mechanism involving a carbene intermediate. Variation of the temperature at which the catalyst is prereduced from 300 to 600 C results in an increase in particle size from 11-53 nm and in an increase in the hydrodechlorination TOF from 2.3 to 5.0 s{sup {minus}1} 25 refs., 8 figs., 4 tabs.
High-speed digital photographic study of an inductively coupled plasma during laser ablation: comparison of dried solution aerosols from a microconcentric nebulizer and solid particles from laser ablation

High-speed photographs and videos of an ICP are used to examine the fates of solid particles produced by laser ablation (LA) in an inductively coupled plasma (ICP). The trajectories, lifetimes, and emission behavior of particles traversing the plasma are studied under a variety of conditions. Desolvated particles from a nebulized yttrium solution and particles ablated from a Y2O3 pellet are mixed and introduced simultaneously into an ICP. High-resolution digital photographs and video sequences are captured using shutter speeds of approximately 65 µs. The plasma behavior of particles generated by a quadrupled Nd:YAG laser (266 nm) and an ArF excimer laser (193 nm) are compared, and either argon or helium is used as the transport gas through the ablation cell. No red emission clouds from YO are visible in the ICP when a 20 µL min−1 nebulizer is used to spray a 2000 ppm aqueous Y solution, suggesting that the wet droplets from this nebulizer desolvate almost completely before entering the ICP. These desolvated particles from the nebulized solution atomize and ionize like the small dry particulates from laser ablation. However, many large ablated particulates are observed to fly through the plasma intact, possibly contributing to signal noise, deposition on the sampler and skimmer cones, and elemental fractionation.
Phenolics, Sugars, Antimicrobial and Free-Radical-Scavenging Activities of Melicoccus bijugatus Jacq. Fruits from the Dominican Republic and Florida

Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H2O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H2O-soluble compounds consistent with therapeutic uses.
On combustion around a porous blowing reactant sphere in a low reynolds number crossflow

Abstract The low Reynolds number limit of flow past a blowing reactant sphere serves to illustrate a powerful theoretical approximation for the conservation equations of combustion. For this approximation to work, the crossflow rate measured by the Reynolds number must be at least one order of magnitude smaller than the blowing Stefan flow rate from the porous sphere (droplet). This approximation, which retains in the equations only the irrotational component of the velocity field, enables analytical solutions to be derived for the mixture fraction and all other scalar variables. The mixture fraction solution permits predictions to be made for the flame including its shape and its position, and their dependence on both crossflow and radial sphere blowing. The porous sphere can also be treated as a transient, decaying fuel droplet in a quasi-steady gas. Using this simplification, an analytical droplet burning rate formula is derived and compared with an empirical correlation formula. Diffusion flame hole d...
System analysis of a short-range SAR repeater

Emerging wide-area synthetic aperture radar (SAR) system concepts call for a single data collection platform to orbit a large (e.g, 20 km) spot at a nominal range of 40 km. The large standoff distance and desire for fine resolution, coupled with a need for persistent real-time sensing, pose a significant challenge in terms of clutter-to-noise ratio (CNR) performance and data processing. Increased CNR and reduced processing load can be achieved by decreasing the range of the SAR system and the size of the area of interest. Employing multiple cooperating SAR systems allows the same overall coverage area to be maintained with a patchwork of SAR footprints. This paper analyzes a high-level system architecture, for multiple SAR systems, that provides uninterrupted coverage over a wide area. System analysis includes eclipsing diagrams, CNR performance and mutual interference issues.