cssi/SciSciGPT-SciSciNet huggingface dataset:
A Low Phase Noise Quadrature LC VCO Using Capacitive Common-Source Coupling

A low phase noise quadrature LC VCO with inherent tail-current shaping is presented. Two identical differential LC VCOs are locked in quadrature with a capacitor connected between their common-source nodes. This capacitor further drives the oscillators into a tail-current shaping mode, which increases their oscillation amplitude and reduces their phase noise. A multi-band 1.9 GHz differential nMOS quadrature LC VCO prototype has been fabricated in a 0.25 ?m BiCMOS process. The measured phase noise is -124.4 dBc/Hz at a 1 MHz offset from a 2.07 GHz carrier while the circuit dissipates only 3 mW from a 1.5 V supply. The quadrature VCO is tunable from 1.75 GHz to 2.1 GHz and the VCO core only occupies 0.625mm2.
Characterizing variability and reducing uncertainty in estimates of solar land use energy intensity

Abstract Estimates of the amount of land used for a defined amount of utility-scale electricity generation in the solar power industry, referred to here as solar land use energy intensity (LUEI), are important to decision makers for evaluating the environmental impact of energy technology choices. However, these estimates for solar LUEI are calculated using three difficult-to-compare metrics and vary by as much as 4 orders of magnitude (0.042–64 m2/MWh) across the available literature. This study reduces, characterizes, and explicates the uncertainty in these values for photovoltaic (PV) and concentrated solar power (CSP) technologies through a harmonization process. In this harmonization process, a common metric is identified and data existing in other forms are converted to the metric, where possible; standard algorithms for calculating solar LUEI are developed; gaps and deficiencies in the literature calculations are identified and remedied; and differences among the resulting estimates are characterized and analyzed. The resulting range of harmonized solar LUEI estimates is reduced to 2 orders of magnitude [5–55 (m2y)/MWh]. Due to variables such as technology and location, there is a significant amount of irreducible variability in general solar LUEI estimates. However, this variability does not necessarily represent uncertainty, as most of it can be explained by choices in calculation input parameters. This study finds that key solar technology- and location-dependent parameters such as insolation, packing factor, system efficiency, and capacity factor all vary widely across studies, and thus all share in the overall variability of solar LUEI. Only land use at the site of solar electricity generation facilities is considered because lifecycle land use beyond the site (for manufacturing, disposal, etc.) is not widely accounted for in the existing literature. This study provides a basis for moving forward with standardized and comparable solar land use studies and for filling gaps in lifecycle solar LUEI.
High-Performance Liquid Chromatography with Electrochemical Detection for the Determination of Nicotine in Plasma

Nicotine in plasma can be determined by high-performance liquid Chromatography with electrochemical detection to upper picogram levels. A simple one-step extraction, which requires only 0.1 mL of plasma and is able to recover>85% of nicotine in plasma, is described. The precision and nicotine recovery of the method, and the application of this assay in nicotine-infused animal studies, are presented.
Response of Electrorheological Fluid-Filled Laminate Composites to Forced Vibration:

Laminate composite beams consisting of metal or polystyrene outer strips and an electrorheological (ER) fluid (corn starch in corn oil) filler were constructed and tested using the standard Oberst test for viscoelastic materials. Application of an electric field of 2 kV/mm increased both the frequency of the various resonance modes and the loss factor associated with each. The apparent elastic modulus and loss factor of the composite beam and those of the ER fluid alone were calculated employing standard ASTM equa tions. Both modulus and loss factors of the composite beams decreased with resonance mode or frequency. The calculated shear modulus of the ER fluid increased with fre quency and the loss factor decreased, their magnitudes being in reasonable accord with those measured directly on the fluid employing a rheometer. However, the calculated mag nitude of the increase (GPa) of the apparent modulus of the metal/ER fluid composite beams with electric field and the fact that it decreases with frequency ...
Brachistochrones in potential flow and the connection to Darwin's theorem

We establish the existence and the asymptotic properties of a path of minimum travel time for a line of particles starting upstream of a sphere or cylinder in potential flow. A connection is made between this brachistochrone path and Darwin's proposition which relates the added mass with the drift volume dragged by a body moving an infinite distance in the fluid. We compute an asymptotic correction to the drift volume for finite distances and show how the brachistochrone path is connected to the reflux volume. We present accurate numerical calculations for the brachistochrone position, point of zero horizontal Lagrangian displacement, reflux and partial drift volumes. These calculations are seen to agree well with the asymptotic predictions even for moderate values of the parameters. In the small Reynolds number regimes, we show that while for the case of Stokes flow past a sphere no brachistochrones exist at finite distances from the sphere, the Oseen correction is sufficient to restore such least-time trajectories. Lastly, the application to a sphere falling in a stratified fluid is discussed using the new drift volume correction formula.
Capital cost of small-scale tidal power plants

A generic methodology is devised for estimating the capital costs of small-scale tidal power plants (1-100 MW rated power). In addition to the general dimensions determining the size of the tidal pond resource (surface area and tidal range) two site-specific dimensions (depth and length of closure structure) are required for this estimate. Dimensionless parameters and variables describing the power plant performance are used in the cost analysis to specify the relative sizes of the power plant components (turbine-generator, power house, sluice gates, cofferdam, and barrage). The generic cost estimates are compared with those used in several site-specific studies. Unit total capital cost (cost per unit of average power produced) is calculated as a function of the size of the tidal pond resource, the latter being measured in terms of the ideal tidal pond power. A range of closure depths and lengths was used in these generic cost estimates. The minimum unit capital cost is shown to depend upon the size of the tidal pond as well as the site-specific dimensions. An optimum turbogenerator size can be determined to minimize the capital cost.
The role of alkali metal cations in Lux-Flood acid-base reactions in fused salt media

Abstract Several inorganic chlorides were prepared from their respective oxides and or oxyanions by chlorination in an aluminum chloride-sodium chloride eutectic system, the aluminum chloride serving as the Lux-Flood acid. The yield of chlorinated product appears to be a function of both bond dissociation energies and geometry. Compounds with central elements unable to assume a configuration other than triangular or tetrahedral did not undergo chlorination in this eutectic system. Yields increased as the size of the central element tended toward that required for octahedral geometry. The more unstable arrangement, with respect to triangular and tetrahedral, allows easier chloride replacement of an oxygen atom.
MRSST a new method to evaluate thermal stability of electrolytes for lithium ion batteries

Abstract The use of the Modified Reactive System Screening Tool (MRSST) to study the thermal stability of electrolytes for lithium ion batteries was demonstrated. Important data for the understanding of the thermal behavior of lithium ion batteries (vapor liquid equilibrium data, heat capacity, heats of vaporization, reaction rates, and heats of reaction) can be obtained with the MRSST. The technique also allows sampling of the system (gas phase or liquid phase) at any time. The thermal stability of EMC and EC was analyzed using the MRSST. The results indicated that EMC is thermally stable until 320 °C, while the EC decomposes at 263 °C generating gases such as CO 2 , O 2 , and H 2 . The effect of O 2 on the thermal stability of EMC was also studied. It was found that EMC thermally decomposes in the presence of O 2 between 220 and 235 °C generating non-condensable gases such as CO 2 .
Tissue-specific Heterogeneity in α-Dystroglycan Sialoglycosylation SKELETAL MUSCLE α-DYSTROGLYCAN IS A LATENT RECEPTOR FORVICIA VILLOSA AGGLUTININ B4 MASKED BY SIALIC ACID MODIFICATION

Because the polypeptide core of α-dystroglycan is encoded by a single gene, the difference in apparent molecular mass between α-dystroglycans expressed in various tissues is presumably due to differential glycosylation. However, little is presently known about the tissue-specific differences in α-dystroglycan glycosylation and whether these modifications may confer functional variability to α-dystroglycan. We recently observed that laminin-1 binding to skeletal muscle α-dystroglycan was dramatically inhibited by heparin, whereas the binding of commercial merosin to skeletal muscle α-dystroglycan was only marginally inhibited (Pall, E. A., Bolton, K. M., and Ervasti, J. M. (1996) J. Biol. Chem. 3817–3821). In contrast to 156-kDa skeletal muscle α-dystroglycan, both laminin-1 and merosin binding to 120-kDa brain α-dystroglycan were sensitive to heparin. We have now examined the laminin binding properties of 140-kDa α-dystroglycan purified from cardiac muscle and observed that like skeletal muscle α-dystroglycan, heparin inhibited cardiac α-dystroglycan binding to laminin-1, but not to merosin. On the other hand, cardiac and brain α-dystroglycans could be distinguished from skeletal muscle α-dystroglycan by their reactivity with the terminal GalNAc-specific lectin Vicia villosa agglutinin. Interestingly, skeletal muscle α-dystroglycan became reactive with V. villosa agglutinin upon digestion with sialidase from Clostridium perfringens,Arthrobacter neurofaciens, or Streptococcus, but not Vibrio cholerae or Newcastle disease virus sialidase. While none of the sialidase treatments affected the laminin binding properties of α-dystroglycan, the sum of our results suggests that skeletal muscle α-dystroglycan contains a novel sialic acid residue linked α2–6 to GalNAc. These properties are also consistent with the cellular characteristics of a GalNAc-terminated glycoconjugate recently implicated in neuromuscular synaptogenesis. Thus, variations in α-dystroglycan sialoglycosylation may prove as useful markers to further elucidate the role of α-dystroglycan glycoforms in different tissues and perhaps within a single cell type.
Nitric oxide protects the skeletal muscle Ca2+ release channel from oxidation induced activation

Reactive oxygen intermediates and nitric oxide modulate the contractile function of skeletal muscle fibers, possibly via direct interaction with the Ca2+ release channel. Oxidants produce disulfide bonds between subunits of the Ca2+ release channel tetramer, and this is accompanied by an increase in channel activity. The sulfhydryl alkylating agent N-ethylmaleimide has three distinct effects on Ca2+ release channel activity: first, channel activity is decreased (phase 1); then with continued exposure the activity is dramatically increased (phase 2); and finally, the channel is again inhibited (phase 3) (Aghdasi, B., Zhang, J. Z., Wu, Y., Reid, M. B., and Hamilton, S. L., (1997) J. Biol. Chem. 272, 3739-3749). Both H2O2 and nitric oxide (NO) block the phase 1 inhibitory effect of N-ethylmaleimide. NO donors, at concentrations that have no detectable effect on channel activity, block intersubunit cross-linking and prevent activation of the channel by the disulfide inducing agent, diamide. These findings support a model in which NO modulates the activity of the Ca2+ release channel by preventing oxidation of regulatory sulfhydryls. However, higher concentrations of NO donors activate the channel and produce intersubunit cross-links, supporting a bifunctional effect of NO on channel activity. Low NO concentrations prevent oxidation of the Ca2+ release channel whereas higher concentrations oxidize it.
Synthesis and assembly of 11S globulins

Summary The 11S globulins are seed proteins found in many grain legumes. After synthesis on endoplasmic reticulum, the globulins are assembled during a series of steps that involve post-translational events and transport of precursors through several intracellular compartments. As an aid in dissecting this process, an in vitro synthesis and assembly system was developed that results in the formation of trimers equivalent in size to oligomers found in endoplasmic reticulum. Assembly of proglycinin trimers in vitro is dependent upon ATP. This observation, together with other evidence, is consistent with the hypothesis that molecular chaperones are involved in the assembly of proglobulin trimers. The 11S proglobulin sub-units in trimers are cleaved post-translationally at an ASN-GLY bond that has been conserved during evolution. Evidence from studies carried out both in vivo and in vitro establish that cleavage of this bond is prerequisite for further assembly of trimers into hexamers. Proteolytic activity has been detected in developing seeds that is capable of cleaving the conserved ASN-GLY. The preponderance of this proteolytic activity in developing seeds is due to glycosylated proteins (Scott et al., 1992), although a small amount of the total activity appears associated with a non-glycosylated peptide. To study the specificity of the prot eases that are glycosylated, mutant pro globulin subunits or peptides were constructed in which amino acids around the conserved ASN-GLY bond were modified, and then the modified subunits were assembled into trimers and subjected to proteolysis. Deletion of the asparagine on the P1 side of the cleaved peptide bond, or substitution of aspartate or glutamine for the asparagine, eliminated cleavage of the subunit precursor. Conservative changes of the amino acids on the COOH-terminal side of the cleavage site (P1' to P7' positions) seemed not to hinder cleavage of proglobulin into mature acidic and basic polypeptides. In contrast to the normal proglycinin subunits found in trimers, nmodified monomers, unfolded or misfolded normal 11S proglobulins, fusions of legumin polypeptides with CAT, and several high methionine mutants of proglycinin, are cleaved into small peptide fragments by the purified, glycosylated protease. Our results demonstrate that cleavage sites other than the conserved ASN-GL Y bond found in unmodified pro globulin subunits are inaccessible to the protease when they are contained in trimers.
The Pentagon Papers: A Critical Evaluation

The Pentagon's study, United States-Vietnam Relations 1945-1967, provides such a mass of significant data as to ensure its enduring usefulness to anyone with a serious interest in the United States' long involvement in Indochina. This enormous collection of documents and commentary undoubtedly deepens our understanding of the political premises and strategic objectives that have underlain the Indochina, and especially the Vietnam, policies of four American administrations. And, on the military level at least, these papers marshal a large body of important documentation and analysis bearing on discussions and decisions within the several administrations concerning U.S. efforts to achieve these objectives. Since an account of these aspects of the three printed versions of the Papers and a breakdown of their coverage is being published in a companion review article, I shall focus largely on other matters, confining myself primarily to a discussion of some of the Pentagon study's major shortcomings. Neither the original nor the published versions of the Papers provide a comprehensive or balanced account of U.S. involvement in Indochina. Much significant documentation has been left out, particularly that relating to the political side of American intervention, and in a number of important instances coverage of the covert level of U.S. operations-military as well as political-is absent. The narrative and analyses in some of the sections are unbalanced and occasionally rest on faulty scholarship. In commenting on these matters I will be giving the closest scrutiny to those sections of the Papers dealing with the period from 1954 through 1960, the ones for which I have had access to the complete text and footnotes of the original study. (They were given to me by the court in connection with testimony I was preparing for the Russo-Ellsberg trial.) Before embarking on such a critical evaluation, however, I
Microstructure of 100 nm damascene copper overburden and lines

A detailed understanding of the crystallography of metallic conductors in modern interconnect systems is essential if we are to understand the influence of processing parameters on performance and reliability. In particular we must be able to evaluate the grain size, crystallographic orientation and residual elastic stress for interconnect lines having widths of tens of nm. Transmission electron microscopy might be the obvious choice, but sample preparation and small sample size make this technique unattractive. On the other hand, electron backscatter diffraction, EBSD, in a scanning electron microscope provides a very attractive tool. Sample preparation can be relatively simple, especially if one investigates the structures immediately after CMP; whole wafers may be measured if desired. One limitation to EBSD is that good diffraction patterns are obtained only from free surfaces and from a limited depth, say a few hundred nm in copper. Here EBSD will be used to compare structures for the pads and 100-nm lines in two variants of a commercial copper damascene interconnect structure. EBSD data collection will be discussed as optimized for characterizing differences in the texture, which were attributed to differences in the processing. By a unique approach to EBSD mapping we found that neither the texture nor the grain size of the overburden, as represented by the contact pads, propagated into the 100 nm lines, though they did propagate into some wider lines.
Correction of chemical-shift artifacts in multislice F-19 imaging with perfluorooctyl bromide.

Chemical-shift artifact correction methods for multislice F-19 imaging with perfluorooctyl bromide are described and results obtained with physical phantoms presented. Utilization of the two long-T2 spectral peaks of PFOB in multislice imaging enhances the imaging efficiency considerably. Simultaneous imaging of the adjacent slices is achieved by appropriately adjusting the slice selection gradient amplitude, the bandwidth, and the slice position offset frequency of the selective RF pulses in relation to the frequency separation between the two peaks. © 1992 Academic Press, Inc.
Surface chemistry of SiO2 and TiO2–SiO2 glasses as determined by titration of soot particles

Abstract Surface charge is a critical issue for various types of glass processing including surface finishing (polishing) and cleaning. Unlike monomeric silicic acid with a pKa of 9.8, glass surfaces can have variable pKa values as determined by extent of Si–O–Si bonding, composition, and structure. The purpose of this study was to determine the surface charge, point of zero charge, and pKas for high purity fused SiO2 and TiO2–SiO2 (∼7 wt% TiO2) glasses. To achieve necessary surface areas for titration, colloidal soot particles were used in this study rather than glass monolith. Soot particles have the same inherent physical and chemical properties as the product glasses that are made by the same chemical vapor flame hydrolysis deposition process. Titration experiments performed in 10−1–10−5 M NaCl solutions revealed dissociation constants (i.e., intrinsic pKa1 and pKa2 values) of 0.0±0.2 and 7.0±0.1, respectively for the fused SiO2 particles, and 0.0±0.1 and 5.0±0.2 , respectively for the TiO2–SiO2 particles. Points of zero charge for each material were calculated as 3.5±0.1 and 2.5±0.1 for the fused SiO2 and TiO2–SiO2 particles, respectively. The role of TiO2 in lowering point of zero charge and pKa2 values is hypothesized to be the result of four-fold coordination as compared to the six-fold coordinated TiO2 used in surface chemistry studies reviewed by this paper.
Characterization of European forage maize lines for stover composition and associations with polymorphisms within O-methyltransferase genes.

Abstract Cell wall components, such as lignin, cellulose, and hemicelluloses, play an important role in the conversion efficiency of corn stover into ethanol. Understanding the molecular basis of cell wall formation is fundamental for marker assisted selection to develop lines more suitable for ethanol production. In this study, we evaluated a set of 40 European forage maize lines for cellulose, lignin, total hemicellulose, glucuronoarabinoxylan (GAX), and monosaccharides, such as arabinose (ara), xylose (xyl), and glucuronic acid (GlcA). The most significant correlations were observed between hemicelluloses and GAX (0.9), and hemicelluloses and cellulose (−0.81). Cell wall digestibility (CWD, estimated by digestible neutral detergent fiber, DNDF) was negatively correlated with Xyl (−0.34). The association analysis between the evaluated traits and polymorphisms within ten “lignin” genes revealed significant associations between polymorphisms within CCoAOMT1, CCoAOMT2, 4CL2 and C4H, and cellulose/xyl, cellulose, cellulose, and GclA, respectively. None of the QTPs identified in this study corresponded to previously reported CWD QTPs.
High temperature rate coefficient measurements of CO + O chemiluminescence

Abstract Spectral intensities from the chemiluminescent reaction CO + O → CO2 + hv have been measured in the range 2600–7000 A from reacting mixtures of H2O2COCO2argon, shock heated in a shock tube to temperatures of 1300 and 2700K. Intergrals of the photon production rate yield an overall rate coefficient I0 = 6.8 (±0.6) × 105, exp(− 1960/T) cm3 mole−1 s−1. Extrapolated to 300K, this rate coefficient is in excellent agreement with the room temperature measurements of Pravilov.
Highlighting anatomical sub-structures in rat brain tissue using lipid imaging

Cell membranes are made up of a mixture of glycerolipids, sphingolipids, gangliosides and cholesterol. Lipids play important roles in a cell's life. However many of their functions have still to be discovered. In the present work, we describe an efficient, easy and rapid methodology to accurately localize phosphatidylcholines and sphingomyelins from a single coronal rat brain section in the cerebrum area. Matrix assisted laser desorption/ionization (MALDI) mass spectrometry was used to profile and image lipids. The best resolved structure was 25–50 μm in the hippocampus.
Series‐parallel graphs: A logical approach

The notions “series-parallel” and “nonseparable” are shown to be logical converses of each other when formulated in a particular dual-like fashion. Self-dual circuit/cutset characterizations are given of series-parallel and of series-parallel nonseparable graphs.
An assessment of the impact of pollution on global cloud albedo

Increased pollution leads to increasing particulate concentrations. Since some particles nucleatedrop formation, clouds will contain, with increasing pollution, more drops per unit volume, andhence will tend to be optically thicker and more reflecting. An opposite effect is also present, inthat increasing absorption also attends increasing pollution. Measurements suggest that theformer (brightening) effect is the dominant one for global climate and that the climatic effect isquite comparable to that of increased carbon dioxide, and acts in the opposite direction. DOI: 10.1111/j.1600-0889.1984.tb00254.x
An automated neutron activation procedure for screening PCB content of oil

An analytical procedure for rapidly screening large numbers of oils for polychlorinated biphenyl (PCB) content has been developed and is now in routine use. Pontential levels of PCBs are inferred from chlorine concentrations as determined using the automated neutron activation analysis (NAA) facility at the Los Alamos National Laboratory Omega West Reactor. The technique is designed to screen up to 200 oil samples per eight hour working day, using a sample volume of approximately 1 milliliter. Because of the automated nature of the analysis, elements in addition to chlorine are determined, when present. These include fluorine, bromine, iodine and sulfur. U.S. National Bureau of Standards (NBS) and U. S. Environmental Protection Agency (EPA) Standard Reference Materials are routinely analyzed for quality assurance purposes. The results of our analyses of these materials for certified elements is discussed as well as results for other non-certified elements observed in the standard materials.
Dielectric anomalies in BaMnF4 at low temperatures

Abstract Static dielectric constant anomalies are observed in BaMnF4 starting (on cooling) at ∼ 30°K for measurements along the a-axis and at ∼ 70°K for measurements along the b-axis. These new effects occur at the Neel temperature and at the two-dimensional ordering temperature, respectively, thus suggesting that they are a consequence of spin ordering.
Urea decomposition facilitated by a urease model complex: a theoretical investigation

Density functional theory calculations were used to examine the role of the urease model complex [Ni2(bdptz)(µ-OH)(µ-H2O)(H2O)2](OTs)3 (A) (bdptz = 1,4-bis(2,2′-dipyridylmethyl)-phthalazine; OTs = tosylate) in the degradation of urea. An elimination mechanism that converts urea to ammonium cyanate was investigated in detail. The lowest energy pathway involves urea coordination through the oxygen atom to a Ni center followed by protonation of a urea NH2 group by the bridging water ligand. Subsequent rotation of the protonated urea, followed by deprotonation of the NH2 by a bridging OH ligand generates the bound, disproportionated urea substrate, HNCONH3, from which ammonium cyanate was produced.
Pressure dependence and thermal quenching of chromium photoluminescence in Cs2NaYCl6:Cr3+

Abstract Photoluminescence spectra of the chromium-doped elpasolite Cs 2 NaYCl 6 :Cr 3+ were measured at ambient and near liquid nitrogen temperatures as a function of pressure in a diamond anvil cell. A pressure-induced blue shift of the broad 4 T 2g → 4 A 2g fluorescence band was observed, culminating in a crossing of the 4 T 2g and 2 E g excited states as evidenced by the appearance of a structured 2 E g → 4 A 2g phosphorescence spectrum. Resolved vibronic structure of the latter permitted determination of vibration frequencies at high pressure. Evidence of a phase transition was observed near the highest pressures attained, ≈ 11 GPa. The pressure dependence of the peak energy of the broad band was interpreted in terms of a pressure-dependent local compressibility. Measurements of photoluminescence lifetimes as functions of pressure and temperature established that the activation energy for thermal fluorescence quenching increases linearly at the rate of 1668 ± 52 cm −1 GPa . A semi-empirical, two-accepting mode, linear- and quadratic-coupling model, calibrated at ambient pressure, predicts a rate of 1758 cm −1 GPa , in substantial agreement with experiment.
Empirical Urban Theory for Archaeologists

I review several bodies of empirical urban theory relevant to the archaeological analysis of ancient cities. Empirical theory is a type of “middle-range theory” (following Robert Merton): sets of concepts and methods that are less abstract, and have greater empirical content, than high-level social theory. The categories of theory reviewed here include environment-behavior theory, architectural communication theory, space syntax, urban morphology, reception theory, generative planning theory, normative theory, and city size theory. Most of these approaches originated in the fields of architecture, planning, and geography, and they directly link the urban-built environment to the actions of people within cities.
Reactive transport of EDTA-complexed cobalt in the presence of ferrihydrite

Abstract Many low-level radioactive wastes, historically disposed in shallow land trenches, are illdefined mixtures of radionuclides and organic chelating agents. The observed migration of nuclides, such as 60 Co, away from burial sites has been attributed, in part, to the formation of aqueous complexes with ethylenediaminetetraacetic acid (EDTA). The stability of Co-EDTA complexes, and thus the fate and transport: of 60 Co in the subsurface, is strongly dependent on the oxidation state of cobalt (log K co(II)EDTA = 18.3; log K Co(III)EDTA = 43.9). The factors that control the oxidation of Co(II) to Co(III) in subsurface environments are not well understood. We conducted a series of column flow experiments to provide an improved understanding of the geochemical processes that control the reactive transport of cobalt in the subsurface. A solution of 0.2 mM Co(II)EDTA 2− in 5 mM CaCl 2 was passed through saturated columns that were packed with ferrihydrite (Fe(OH) 3 )-coated Si0 2 . During transport through the column, a portion of the Co (II) EDTA 2− was oxidized to Co (III) EDTA − ; the amount of oxidation reached a steady-state under oxic conditions. Transport of the oxidized species, Co(III)EDTA − , was substantially more rapid than the transport of Co(II) EDTA 2− . The retardation of both Co-EDTA species and the extent of cobalt oxidation increased as the pH decreased. These results are consistent with the hypothesis that the association of Co(H)EDTA 2− with the ferrihydrite surface is essential for the charge-transfer involved in the oxidation reaction. Co(III)EDTA- exhibited less retardation because this monovalent anion had a lower affinity for the surface than the divalent Co(II)EDTA 2− . At faster flow rate, the retardation of Co(II)EDTA 2− decreased whereas Co (III) EDTA — breakthrough occurred later; the amount of Co(III)EDTA − formed decreased with increasing flow rate. Under anoxic conditions, the oxidation of Co(II)EDTA 2− was decreased, but was not eliminated, suggesting that ferric iron may serve as an oxidant in the system. The loss of oxidative sites under continuous exposure to Co(II)EDTP 2− and the blocking of oxidative sites by ions residing on the ferrihydrite surface resulted in a slow decline in the amount of oxidation under anoxic conditions. The oxidation of Co(II)EDTA 2− effectively competed with other geochemical reactions such as the Fe(III)-induced dissociation of Co(II)EDTA 2− complexes under oxic and anoxic conditions. These results indicate that an iron mineral can be more important for the formation of Co(III)EDTA 2− in the subsurface than the mineral is important for the dissociation of Co(II)EDTA − and the concomitant formation of Fe(III)EDTA − . The results suggest that conditions of pH and flow rate that inhibit the formation of the very stable Co(III)EDTA − also promote the undesirable rapid transport of Co(II)EDTA 2− posing a challenge to the selection of future waste sites and the development of remedial strategies for existing sites impacted by EDTA-complexed 60 Co.
Unsteady non-viscometric flows in tubes driven by rotational boundary waves—I: Longitudinal field

Abstract The unsteady non-viscometric motion of a memory integral fluid of order three in a rigid, circular, straight tube has been investigated. The motion is driven by a constant longitudinal pressure gradient and a periodic forcing from the boundary made up of superposed sinusoidal, rotational boundary waves. A regular perturbation is used to study the time-periodic longitudinal field for a range of viscoelastic liquids and driving parameters. Qualitative results obtained are independent of the explicit forms of the constitutive functions, the kernels of the memory integral fluid of order three, which are needed only for quantitative predictions. It is shown that anomalous steady longitudinal viscometric flows may exist due to frequency cancellation. The elastic and shear rate dependent viscosity characteristics of the fluid play important parts in setting up the oscillatory velocity field. In particular, shear-thinning in periodic shear is the dominant mechanism in smoothing out the effects of elasticity, and in increasing the velocities. A parametric study of the longitudinal oscillatory velocity field is presented for a range of liquids and driving conditions. The integral fluid shows drastic longitudinal steady velocity increases due to the interaction of the oscillatory, zero mean time average, transversal shear field with the longitudinal simple steady shear. A parametric study of the change in mass transport is also presented for a range of liquids to show that contrary to what is sometimes assumed, both elasticity and shear-thinning in oscillatory shear play important roles in defining the enhancement. In particular, nonlinear-elastic properties of the integral fluid of order three act to decrease the enhancement driven by orthogonal waves.
Statistical design and analysis of computer experiments for the generation of parsimonious metamodels

We review the use of statistical design and analysis of computer experiments (DACE) for the generation of parsimonious, surrogate models, also known as metamodels. Such metamodels are used to replace cpu- or memory-intensive, discretized approximations that often arise in MEMS and MOEMS. Emphasis is placed on optimal designs.
Comparison of Plasma Concentrations of Warfarin Measured by Both Simple Extraction and TLC Methods

Human volunteers received 25-mg. single oral doses of sodium warfarin. Ninety-three plasma samples were independently assayed by: (a) a simple extraction method, and (b) a TLC method using a UV instead of a fluorescent end-point. Both assays employed 7.5-cm. pathlength cells and the Cary 14 UV spectrophotometer. The assays were concluded to be equivalent and to measure only unchanged warfarin after single doses, since: (a) the least-squares line forced through the origin when assays by the extraction method were plotted against assays by the TLC method had a slope of 1.00; (b) of the differences (TLC — extraction), 44 were positive, 2 were zero, and 47 were negative; and (c) average elimination half-lives of warfarin estimated from terminal plasma concentrations measured by the two methods were not significantly different. The absolute value of the differences averaged 0.17 mcg./ml. with a SD of 0.14 mcg./ml. One may assume that each assay had an average deviation of 0.085 mcg./ml. from the “true” warfarin concentration and that the deviation was independent of the plasma concentration in the range studied (0.1–4.5 mcg./ml.).
MOSFET Gate Oxide Reliability: Anode Hole Injection Model and its Applications

We review the development of the anode hole injection (AHI) model for reliability projection of the silicon dioxide gate dielectric. The experimental and theoretical foundation of the AHI model is presented. Recent development and implications for the reliability of ultra-thin oxides are discussed. AHI is used to illuminate the questions of E versus 1/E models and field-driven versus voltage-driven models. Building on the concept of effective thinning, the AHI model is applied for the interpretation of defect-induced breakdown data and for optimizing oxide screening conditions. Circuit level reliability projection as a function of operating time, temperature, and power supply voltage is also illustrated.
Dormancy in southwestern cotton boll weevils : a comparative physiological study of Anthonomus grandis in wild and domesticated cotton bolls

Abstract Thurberia weevils ( Anthonomus grandis Var. thurberia Pierce) remaining dormant in bolls of the wild cotton shrub, Gossypium thurberi Todaro, show little change in glycogen from January to August ranging from 7.0 to 11.6 μg/mg wet wt. Cotton boll weevils ( Anthonomus grandis Boheman) in bolls of domesticated cotton ( G. hirsutum L.) showed a steady decline in glycogen levels from December to May falling from 5.8 ± 1.5 to 1.7 ± 0.2 μg/mg wet wt. Trehalose levels in the thurberia weevil remain relatively constant from January to July ranging from 8.8 to 10.8 μg/mg wet wt and only sharply decline in August to 3.8 ± 1.8 μg/mg wet wt. Cotton boll weevils also maintain high trehalose levels from January to May ranging from 6.7 ± 1.1 to 9.5 ± 0.8 μg/mg wet wt. Temperatures of crystallization followed a gradual exponential increase in both the thurberia and cotton boll weevils: −17.4°C ± 0.3 (Feb.) to −15.3°C ± 1.3 (June) and −18.5°C ± 0.5 (Dec.) to −14.4°C ± 1.1 (June), respectively. The data indicate that these insects survive the period of adverse conditions in a metabolically arrested state characteristic of oligopause.
Algebra for (m, p) switching nets

This paper describes the manner in which the (m, p) switching-network configurations combine. It is shown that this logic (algebra) is isomorphic to the many-valued logic of Post. Application of this logic in designing error-free logic systems is indicated.
Graded Casting: Process Control for Producing Tailored Profiles

The concept of a graded casting for processing composite materials having a smooth through-the-thickness transition in composition is further developed and refined. An empirical model is presented that uses data from the casting of constant composition slips to predict casting rates for slips of changing composition. The model was tested by producing Al{sub 2}O{sub 3}-ZrO{sub 2} composites having tailored composition profiles. Both linear- and nonlinear-graded compositions were processed, and it was shown that the model could correctly predict the changes necessary during casting to produce the selected contours. Analysis of the composites by EDS and SEM revealed a smooth transition in composition through the thickness of sintered bodies and a relatively good distribution of the phases.
Premature Beats Elicit a Phase Reversal of Mechanoelectrical Alternans in Cat Ventricular Myocytes A Possible Mechanism for Reentrant Arrhythmias

Background Alternans of the ST segment of the ECG is an important risk factor for sudden cardiac death. Premature beats during alternans and the development of discordant alternans are associated with the onset of ventricular tachycardia and ventricular fibrillation. Moreover, premature beats can switch the pattern of alternans from discordant to concordant alternans. The mechanisms of how a premature beat can elicit a pattern shift in alternans and develop malignant ventricular arrhythmias are not clear. The purpose of this cellular study was to determine the electrical and mechanical restitution properties during cycle length–induced alternans and to determine how premature and delayed beats affect the resultant phase of alternans. Methods and Results A perforated patch recording method and video-based edge detector were used to record action potentials and contractions, respectively, from single ventricular myocytes enzymatically isolated from the cat heart. Electrical and mechanical restitution curves...
Picosecond Image Converter Streak Cameras for Laser Diagnostics

The requirements and techniques for time resolved (<1 nsec) diagnostics of laser pulses are reviewed. The advantages and limitations of applying gated image converter streak cameras to the problem of laser pulse diagnostics are discussed. The design and operation of a unique 10-psec time resolution streak camera is described. The compact size of the camera results primarily from the use of a micro-channel tube for image intensification. Optically triggered avalanche transistor circuits provide reliable, low jitter electronic operation of the streak tube. The S-1 photocathode response allows direct measurement of neodymium laser pulses. Examples of the uses of streak cameras for laser diagnostics and the data obtained are presented. Comments on additional applications and the development of streak cameras with extended capabilities are included.
Frequency stabilized mode locked laser with 1000 finesse intracavity etalon

A low noise, frequency stabilized, semiconductor based, 10.287 GHz mode-locked laser with 1000 finesse intracavity etalon is demonstrated with a timing jitter (1Hz – 100MHz) of 10.9 fs and optical frequency fluctuations less than 150 kHz.
Multiparty authorization framework for data sharing in online social networks

Online social networks (OSNs) have experienced tremendous growth in recent years and become a de facto portal for hundreds of millions of Internet users. These OSNs offer attractive means for digital social interactions and information sharing, but also raise a number of security and privacy issues. While OSNs allow users to restrict access to shared data, they currently do not provide effective mechanisms to enforce privacy concerns over data associated with multiple users. In this paper, we propose a multiparty authorization framework that enables collaborative management of shared data in OSNs. An access control model is formulated to capture the essence of multiparty authorization requirements. We also demonstrate the applicability of our approach by implementing a proof-of-concept prototype hosted in Facebook.
Arizona: A History

Hailed as a model state history thanks to Thomas E. Sheridan's thoughtful analysis and lively interpretation of the people and events shaping the Grand Canyon State, "Arizona" has become a standard in the field. Now, just in time for Arizona's centennial, Sheridan has revised and expanded this already top-tier state history to incorporate events and changes that have taken place in recent years. Addressing contemporary issues like land use, water rights, dramatic population increases, suburban sprawl, and the US-Mexico border, the new material makes the book more essential than ever. It successfully places the forty-eighth state's history within the context of national and global events. No other book on Arizona history is as integrative or comprehensive. From stone spear points more than 10,000 years old to the boom and bust of the housing market in the first decade of this century, "Arizona: A History "explores the ways in which Native Americans, Hispanics, African Americans, Asians, and Anglos have inhabited and exploited Arizona. Sheridan, a life-long resident of the state, puts forth new ideas about what a history should be, embracing a holistic view of the region and shattering the artificial line between prehistory and history. Other works on Arizona's history focus on government, business, or natural resources, but this is the only book to meld the ethnic and cultural complexities of the state's history into the main flow of the story. A must read for anyone interested in Arizona's past or present, this extensive revision of the classic work will appeal to students, scholars, and general readers alike.
Characterization of virulent isolates of vesicular stomatitis virus in relation to interference by defective particles

To investigate the role that defective interfering (DI) particles might conceivably play in the epizootiology of vesicular stomatitis, two virulent New Jersey (NJ) isolates from the 1982-1983 epizootic in the United States (US) were compared with three laboratory adapted strains of vesicular stomatitis virus (VSV): NJ Hazelhurst, NJ Ogden and Indiana San Juan. Successive undiluted passages showed that the virulent isolates did not readily exhibit 'autointerference' because they did not readily generate and amplify DI particles. Viral RNA synthesis of isolates that were exposed to homotypic or heterotypic DI particles generated from the laboratory strains showed that the isolates were totally resistant to the heterotypic DI particle and partially resistant to the homotypic DI particle. In contrast, Indiana San Juan and NJ Ogden were inhibited by hetero- or homotypic DI particles. NJ Hazelhurst more closely resembled the isolates. This demonstrates that virulence of VSV in its natural setting may be related to a number of factors, including the slower generation and amplification of endogenous DI particles, as well as the increased resistance of the virus to some pre-existing DI particles.
Does the market value racial and ethnic concordance in physician-patient relationships?

Objective To determine if the market-determined earnings per hour of physicians is sensitive to the degree of area-level racial/ethnic concordance (ALREC) in the local physician labor market.
Petropolis and Environmental Protest in Cross-National Perspective: Beaumont–Port Arthur, Texas, versus Minatitlan-Coatzacoalcos, Veracruz

Driving into Port Arthur or Beaumont, Texas, at night, you encounter a horizon ablaze with the lights of the strange cityscape that is the modern oil refinery. Near the mouth of the Neches River, the refinery’s clumped and turreted towers, erected by some of the nation’s largest corporations—Gulf, Texaco, and Mobil—have punctuated the skyline for over half a century. American historians now know much about the boomtowns that rapidly grew around early oil fields and also about the immense impacts of gasoline on twentieth-century American lives, but they sometimes fail to recall that refineries, too— the oil industry’s version of the factory—have cast a long historical shadow. Cracking and fractionating incoming streams of crude oil into saleable commodities, larger refineries such as those in Beaumont and Port Arthur have quietly spawned their own distinctive environmental transformations. Drawing neighborhoods of petrochemical plants their way and nourishing new residences and commerce, the long-term local impact of refineries in this corner of Texas suggests the phenomenon of petropolis. Petrorefers to an industrial specialization in oil refineries and petrochemical plants, drawing on technologies that inevitably resembled one another no matter where they arose. The term -polis suggests another commonality: the buildup of not just a downtown but also a metropolitan area, uniting core cities with satellite towns via a regional economy dominated by nonrural jobs and land uses. More familiar to most Americans than the industry’s factory towns are its impacts on the natural environment. The recent furor over the 2010 BP oil spill in the Gulf of Mexico serves as only the latest reminder of how, since the 1960s, discharge and damage from the oil business have catalyzed America’s environmental conscience. Yet historians of environ mental protest long assumed its roots were to be found far beyond any petropolis, in wilder places such as national parks, where nature was easy to notice and romanticize. Beaumont– Port Arthur offers a revealing counterpoint, for over the last century it too begat a native stirring of environmental concerns, as did petropolises in other parts of the world. 1