cssi/SciSciGPT-SciSciNet huggingface dataset:
Solving Diophantine Equations

Publisher Summary This chapter discusses diophantine equations. It is shown that every recursively enumerable set is diophantine and hence that there is no algorithm for telling whether an arbitrary diophantine equation has a solution. The set of solvable (in N) diophantine equations is recursively enumerable but not recursive, the problem is to find ways of proving equations are unsolvable and of characterizing classes of equations for which there is a decision method. By the usual fixed-point argument, other unsolvable equations from any given recursively enumerable set of unsolvable diophantine equations can be constructed. This method, at least, has no parallel in classical number theory.
Emergent Data Mining Tools for Social Network Analysis

This chapter identifies a number of the most common data mining toolkits and evaluates their utility in the extraction of data from heterogeneous online social networks. It introduces not only the complexities of scraping data from the diverse forms of data manifested in these sources, but also critically evaluates currently available tools. This analysis is followed by a presentation and discussion on the development of a hybrid system, which builds upon the work of the open-source Web-Harvest framework, for the collection of information from online social networks. This tool, VoyeurServer, attempts to address the weaknesses of tools identified in earlier sections, as well as prototype the implementation of key functionalities thought to be missing from commonly available data extraction toolkits. The authors conclude the chapter with a case study and subsequent evaluation of the VoyeurServer system itself. This evaluation presents future directions, remaining challenges, and additional extensions thought to be important to the effective development of data mining tools for the study of online social networks.
External anions and cations distinguish between AMPA and kainate receptor gating mechanisms

Experiments were designed to examine if ion-flow through alpha-amino-3-hydroxy-5-methyl-isoxazolepropionic acid (AMPA) or kainate receptors interferes with protein structures associated with the gating machinery. Gating was studied using ultra-fast drug perfusion of outside-out patches containing rat GluR-A or GluR6 subunits excised from transfected human embryonic kidney cells. Deactivation rates of GluR6 kainate receptors observed following brief L-glutamate (10 mM Glu, 1 ms) applications differed by two to threefold in high (405 mM symmetrical Na(+), tau(decay) = 2.7 ms at -100 mV) and low ionic strength (55 mM, tau(decay) = 1.1 ms) solutions. In comparison, GluR-A AMPA receptors were much less sensitive. Ion effects on GluR6 receptors did not reflect surface potential screening or ion-agonist competition at the agonist-binding site since deactivation rates were slower in high ionic strength solutions. Moreover, the apparent agonist affinity did not decrease with increasing ionic strength (e.g. 55 mM, EC(50) = 110 microM vs. 405 mM, EC(50) = 61 microM). GluR6 responses were strongly dependent on ions present on the external, but not the internal, side of the plasma membrane. Decay kinetics was regulated by the type of ion present suggesting that the chemical nature of the solution, not its ionic strength, governed channel behaviour. Both external anions and cations modulated the amplitude and decay kinetics of GluR6 responses in a concomitant manner. AMPA receptor responses recorded in identical ionic conditions did not exhibit this behaviour. These results identify a novel mechanism that distinguishes AMPA and kainate receptors. External ions regulate the gating machinery of kainate receptors through an allosteric mechanism that involves both anions and cations.
The Amytal interview: History and current uses

Abstract The Amytal interview's usefulness is limited and its use is not specific for any particular psychiatric condition. Used properly in particular cases, however, the technique may be of extraordinary value. The history of its use is reviewed and current indications and contraindications are summarized.
DEVS approximation of infiltration using genetic algorithm optimization of a fuzzy system

The infiltration process is generally described by a nonlinear differential equation, which can be solved by iteration methods such as a Newton-Raphson method. In this paper we propose a Discrete Event System Specification (DEVS) model for Green-Ampt infiltration. We show that this model can be approximated using Genetic Algorithm optimization of a fuzzy system. The fuzzy approximation is shown to be more accurate than the Taylor series approximation recently proposed.
Preliminary evidence that the feeding rates of generalist marine herbivores are limited by detoxification rates

Herbivores tend to increase feeding rate and fitness when consuming a mixed diet relative to a single diet. According to the detoxification limitation hypothesis (DLH), feeding choices and rates when confronted with chemically rich plants are determined by herbivore physiology, and specifically by the metabolic pathways that herbivores use to manipulate secondary metabolites. We tested two predictions of the DLH using two generalist herbivores, the urchin Arbacia punctulata and amphipod Ampithoe longimana. These herbivores have geographic ranges which overlap with brown seaweeds that produce diterpenes (Dictyota menstrualis, D. ciliolata) and a green seaweed that produces sesquiterpenes and diterpenes (Caulerpa sertularioides). As predicted by the DLH, herbivore consumption rates in no-choice feeding assays were limited by extract intake rates. This suggests an upper limit in the herbivores’ abilities to physiologically manipulate seaweed metabolites. Contrary to a second prediction of the DLH, urchins consumed equal amounts of foods coated with limiting concentrations of two seaweed extracts offered singly, as a mixture, or as a pairwise choice. This result suggests that secondary metabolites of these seaweeds are manipulated by a linked set of detoxification pathways. Improving our understanding of the mechanisms that underlie diet mixing depends on greater attention to the physiology of herbivore resistance to secondary metabolites.
THE AQUEOUS PERIODATE OXIDATION OF AROMATIC AND ALIPHATIC CARBOXYLIC ACID DISULFIDES

Abstract The water-soluble carboxylic acid-functionalized aromatic disulfides, 3,3′-dithiodibenzoic acid and 5,5′-dithiodiisophthalic acid (5,5′-dithiodi(1,3-benzenedicarboxylic acid)) were prepared and their rates of periodate oxidation to the sulfonic acids were determined. The reaction is first order in each of the reactants which indicates that the slow step is the initial oxidative cleavage step. These aromatic disulfides are oxidized to the sulfonic acids 4–8 times more slowly than a typical aliphatic disulfide. In all cases, water solubility of the disulfide is of prime importance. The periodate oxidation of two aliphatic carboxylic acid analogs were also examined, however, in these cases, the reactions were multiphasic and intermediate thiosulfinates were observed by 1H NMR along with the sulfonic acids.
Spin transfer in bilayer magnetic nanopillars at high fields as a function of free-layer thickness

Spin transfer in asymmetric Co-Cu-Co bilayer magnetic nanopillars junctions has been studied at low temperature as a function of free-layer thickness. The phase diagram for current-induced magnetic excitations has been determined for magnetic fields up to $7.5\phantom{\rule{0.3em}{0ex}}\mathrm{T}$ applied perpendicular to the junction surface and free-layers thicknesses from $2\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}5\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. The junction magnetoresistance is independent of thickness. The critical current for magnetic excitations decreases linearly with decreasing free-layer thickness, but extrapolates to a finite critical current in the limit of zero thickness. The limiting current is in quantitative agreement with that expected due to a spin-pumping contribution to the magnetization damping. It may also be indicative of a decrease in the spin-transfer torque efficiency in ultrathin magnetic layers.
Servants of the State: Managing Diversity and Democracy in the Federal Workforce, 1933-1953

Servants of the State traces the halting rise of a pluralistic attitude in hiring and promotion procedures within the federal government. Ranging from the Great Depression to World War II to the early days of both the civil rights movement and the Cold War, Margaret Rung reveals how circumstances in each of these eras shaped how federal managers conceptualized merit for female and African American workers. At the same time, Rung shows how labor relations, as practiced by the nation's most prominent employer, reflected and fostered broader social and cultural debates concerning American identity in a diverse and democratic society. Rung draws on an impressive array of sources, including previously unexamined archival materials, oral histories, and personnel manuals, as she tells how federal administrators and employees destabilized earlier patterns of discrimination based on white male privilege - only to confront new challenges engendered by personnel trends grounded in sociology and psychology. In the end, a renewed commitment to democracy and social justice in the 1930s and 1940s did not entail a complete restructuring of government labor relations policy or the merit system. By midcentury, labor segmentation based on race and gender within the federal civil service still existed, as did the tension between managers' desire to support individual initiative and their desire to remedy categorical discrimination against blacks and women. Questions of individual merit versus group rights remain central to our discussions about the relationship between equality and pluralism. Servants of the State highlights the fluid meaning of merit by focusing on this critical concept in the public-sector workplace. By covering an area frequently ignored by historians, it adds an important historical dimension to current affirmative action debates and other issues that touch on pluralism and individual opportunity.
Prolonged ambulatory monitoring of colonic motor activity in the pig.

Abstract The aim of this study was to develop a chronic model suitable for repeated, long-term studies of the interaction of behavior and colonic function in unrestrained pigs. Cecostomies were created in three 20–30 kg micropigs under general anesthesia. Fistulas were created by suturing the bowel to the abdominal wall. Recordings were made by passing a small (8F) solid-state pressure transducer through the fistula into the proximal bowel and connecting it to a battery-operated data logger worn in a vest on the pig's back. Cecostomies have remained patent and trouble-free for over 18 months. No serious infections have occurred. Preliminary data from a total of thirteen 24-h recording sessions showed 54% of all contractile activity to be in the 2–4 cpm frequency range. Increased motility was seen following meals and upon morning awakening. Motility was minimal during the night. Infrequent (10.31 ± 2.05/24 h; mean ± SD) propagated contractions were also noted. These contractions were generally of low amplitude (33.24 ± 3.81 mmHg). These techniques allow prolonged, intraluminal recordings to be made from the colon of the unrestrained pig.
Modelling and simulation of a novel multi-radial-flow CVD reactor

Abstract A high-capacity novel CVD reactor is proposed. A mathematical model has been formulated, solved numerically and simulations run to show the effects of design variables for the novel CVD reactor. The novel reactor configuration offers a dramatic increase in wafer capacity. A hydrodynamic model based on the classical treatment of the radial-flow catalytic reactor was used to analyze the gas distribution to wafers along the entire reactor axis. Film growth rates were obtained from a model based on chemical reaction engineering principles, using published kinetics for silicon deposition. The simulation results indicated that the reactor dimensions and operating conditions can be specified in such a way as to give good cross-wafer and susceptor-to-susceptor film uniformity.
Platelet serotonin uptake and paroxetine binding among allelic genotypes of the serotonin transporter in alcoholics.

Expression rates of long (L) and short (S) alleles of the serotonin (5-HT) transporter (5-HTT) gene have been shown to differ under various circumstances. We compared 5-HTT uptake (function) level and paroxetine binding (density) in platelets of alcoholics as indices of 5-HTT expression rate among LL, LS, and SS genotypes. Concentration curves of [3H]5-HT and [3H]paroxetine were used to quantify the equilibrium constant (Km) and maximum 5-HT uptake rate (Vmax) for 5-HTT uptake into intact platelets and the dissociation constant (Kd) and maximum specific binding density (Bmax) for paroxetine binding to platelet membranes, respectively. Genotypes were determined using electrophoresis with fluorescent markers. Vmax for 5-HTT uptake did not correlate with Bmax for paroxetine binding (r=−0.095, P=0.415). Means of Vmax and Bmax did not differ in a statistically significant manner among LL, LS, and SS genotypes in these alcoholic subjects. However, Vmax for LL and SS appeared to have a bimodal distribution, so the percentage of subjects with Vmax <200 fmol/min-107 platelets was statistically significantly higher in LL than in SS (51.5% vs. 22.7%, respectively), with an odds ratio of 3.6 (P<0.05). The percentage of Vmax <200 fmol/min-107 platelets for LS was 39.3% (not significant vs. LL or SS). Previous studies of healthy human controls have shown that 5-HTT density in raphe nuclei and 5-HTT uptake in platelets are higher in the LL genotype than in S carriers. Our findings in currently drinking alcoholics support the hypothesis that those with the LL genotype of the 5′-HTTLPR region of the 5-HTT gene have reduced 5-HTT function.
Models of hepatocarcinogenesis in the rat--contrasts and comparisons.

(1986). Models of Hepatocarcinogenesis in the Rat—Contrasts and Comparisons. CRC Critical Reviews in Toxicology: Vol. 17, No. 1, pp. 61-89.
Correcting Myths and Misconceptions about Allergies to Pets

(1990). Correcting Myths and Misconceptions about Allergies to Pets. Anthrozoos: Vol. 3, No. 4, pp. 230-233.
Selective detection of histologically aggressive prostate cancer: an Early Detection Research Network Prediction model to reduce unnecessary prostate biopsies with validation in the Prostate Cancer Prevention Trial.

BACKGROUND: Limited survival benefit and excess treatment because of prostate-specific antigen (PSA) screening in randomized trials suggests a need for more restricted selection of prostate biopsy candidates by discerning risk of histologically aggressive versus indolent cancer before biopsy. METHODS: Subjects undergoing first prostate biopsy enrolled in a multicenter, prospective cohort of the National Cancer Institute Early Detection Research Network (N ¼ 635) were analyzed to develop a model for predicting histologically aggressive prostate cancers. The control arm of the Prostate Cancer Prevention Trial (N ¼ 3833) was used to validate the generalization of the predictive model. RESULTS: The Early Detection Research Network cohort was comprised of men among whom 57% had no cancer, 14% had indolent cancer, and 29% had aggressive cancer. Age, body mass index, family history of prostate cancer, abnormal digital rectal examination (DRE), and PSA density (PSAD) were associated with aggressive cancer (all P 0.1 ng/mL/cc or abnormal DRE. When PSAD is <0.1 ng/mL/cc, family history or obesity can identify biopsy candidates. CONCLUSIONS: A predictive model incorporating age, family history, obesity, PSAD, and DRE elucidates criteria whereby 1=4 of prostate biopsies can be averted while retaining high sensitivity in detecting aggressive prostate cancer. Cancer 2012;118:2651-58. V C 2011 American Cancer Society.
Reconfigurable transmission line for a series-fed Ku-band phased array using a single feed

The paper presents a novel approach to realize a low-cost phased array using a simple feeding mechanism. Specifically, a single coplanar stripline (CPS) transmission line is used to feed the antenna array elements. By controlling the CPS's dielectric properties using a movable dielectric plunger, scanning is achieved. Due to its simplicity, single feed, and no phase shifters, this approach leads to a dramatic reduction in cost which does not scale for larger arrays.
Laboratory-Based Surveillance for Vancomycin-Resistant Enterococci: Utility of Screening Stool Specimens Submitted for Clostridium difficile Toxin Assay

OBJECTIVE: To study vancomycin-resistant enterococci (VRE) gastrointestinal colonization prevalence in high-risk hospitalized patients and to assess the cost and utility of this laboratory-based surveillance. SETTING: Large university teaching hospital. DESIGN: Quarterly prevalence culture survey of 50 stool specimens submitted for Clostridium difficile toxin A assay from October 1996 through June 1999 (n=526). Screening culture survey of all C difficile-positive stool specimens from July 1998 through June 1999 (n=140). PATIENTS: Specimens for analysis were collected from patients who were admitted to the hospital and who had C difficile toxin A testing ordered. Patient samples were excluded from analysis if they were obtained from patients not hospitalized at UCLA Medical Center, if the C difficile toxin assay result was indeterminate, or if the patient was known to have previous VRE colonization or infection. RESULTS: During quarterly surveillance, VRE was detected in 19.8%, C difficile toxin A in 9.5%, and both VRE and C difficile toxin A in 3.2% of stool specimens submitted for C difficile toxin assay. Patients whose stool specimens were positive for C difficile toxin A were significantly more likely than those whose specimens were negative to have VRE detected (odds ratio, 2.3; 95% confidence interval, 1.2-4.5). Based on these findings, in July 1998, we began routine screening of all C difficile-positive stool specimens for VRE. From July 1998 through June 1999, 58 (41.4%) of 140 patients with C difficile-positive specimens had VRE newly detected in the stool. The combined cost of the two laboratory-based surveillance strategies was approximately $62 per VRE-positive patient identified and $5,800 per year. CONCLUSION: Quarterly surveillance of stool submitted for C difficile assay combined with screening all C difficile-positive stools is a cost-effective and efficient strategy for detecting VRE stool colonization among high-risk hospitalized patients. Such a laboratory-based surveillance should be included as part of a comprehensive program to limit nosocomial VRE transmission.
The consistency of number theory via herbrand's theorem

In this sequel to [7] the method of the consistency proof presented there is extended to provide a proof of the ω -consistency of the systems of number theory which were there shown consistent. This proof yields sharp bounds on the ordinal recursions required to establish the κ -consistency of these systems. The main technical innovation of this proof is the extension of what are essentially the methods of Ackermann [1] for handling finite sets of critical formulae of the first and second kinds to apply as well to sets of critical formulae in which the rank ordering is transfinite. The notation, definitions, and results of [7] will be presupposed throughout; we suggest the reader keep a copy of that paper at hand.
The Chloroplast-Located Homolog of Bacterial DNA Recombinase

The cDNA for the chloroplast-located homolog of bacterial RecA protein, designated recA-AT, was placed in a plasmid appropriate for in vitro transcription and translation. Translation with 35S-labeled Met permitted demonstration of uptake of the protein product into isolated pea chloroplasts, and processing to a mature size. Preliminary evidence for the first amino acid was estimated from results using both 35S-Met and 3H-Leu for in vitro transcription and translation, followed by uptake into chloroplasts and processing. The labeled protein was subject to sequential amino acid hydrolyses, and radioactivity was measured in each round. Induction of gene transcription in leaves infiltrated with the DNA-damaging agent, methyl methane-sulfonate was shown by Northern blot analysis. Further constructs were made for over-expression of the gene in E. coli; and one out of many tried permitted production of some soluble protein. Extracts from transformed bacteria were shown to have RecA activity using the "POM" assay [Bertrand et al. (1993) Nucl. Acids Res. 21:3653] for DNA strand transfer. The protein was purified to close to homogeneity using methods developed for E. coli RecA isolation.
Meta-analysis of randomized controlled trials as a method of estimating rare complications of non-steroidal anti-inflammatory drug therapy.

Abstract The design of randomized controlled trials to assess the efficacy of pharmacological measures for the prevention of the gastrointestinal side-effects of anti-inflammatory drugs requires an accurate estimate of excess risk under controlled conditions. Photocopies of 952 randomized controlled trial publications were obtained after scanning titles and abstracts of a MEDLINE computer search, 427 were excluded for obvious reasons, and 525 were again photocopied after obliterating source and results. Selection criteria were: the presence of a non-anti-inflammatory drug control group; at least 4 days of therapy; at least 3 days without anti-inflammatory drugs before randomization; no complicating background drugs; mention of side-effects; and a clear differentiation of gastrointestinal complications. Observer error, with two independent readings, for inclusion suitability in the study was 19% for Methods and 9% for Results. For the 44 aspirin trials, the mean therapy duration was 357 days; the unweighted rate difference between therapy and control groups ( +/- 1 S.E.M.) for ulcer was 0.006 +/- 0.003, for gross haemorrhage 0.006 +/- 0.002 and for unspecified gastric symptoms 0.03 +/- 0.01. In 123 non-aspirin non-steroidal anti-inflammatory drug (NA-NSAID) trials, the mean duration was 67 days; the unweighted rate difference for ulcer was 0.0005 +/- 0.0003, for gross haemorrhage 0.007 +/- 0.004 and for unspecified gastric symptoms 0.02 +/- 0.005. Risk differences were also pooled using the DerSimonian and Laird method, which weights studies inversely according to variance. Using this method, only the unspecified gastric symptoms for non-aspirin non-steroidal anti-inflammatory drugs (NA-NSAIDs) and the haemorrhage for aspirin were found to be statistically significant. Longer studies have higher risk differences. Randomized control trials to determine prophylactic efficacy against haemorrhage (that is, to demonstrate a reduction of ulcer rate in the therapy group to the rate of controls) would require 190 patients in each group for NA-NSAIDs in studies of 2-6 months; 950 subjects would be needed to detect a 50% reduction. Randomized control trials to determine a reduction in ulcer rate to that of controls in patients on aspirin for more than 6 months would require 700 subjects in each group; 3346 subjects would be needed to detect a 50% reduction. Such studies are feasible.
Hyperosmolemic changes following experimental ethylene glycol intoxication in dogs.

SUMMARY Experimental ethylene glycol toxicosis in dogs produced a marked increase in serum osmolality. By comparing measured and calculated serum osmolality and relating this difference to plasma ethylene glycol, it was determined that ethylene glycol was primarily responsible for the hyperosmolemia. Osmometry may provide a useful adjunct to other diagnostic tests in identifying ethylene glycol intoxicated dogs during the early, most treatable, stage of toxicosis.
Mechanisms for the retardation of fatigue cracks following single tensile overloads: behavior in aluminum-lithium alloys

Abstract Mechanisms for the transient crack growth retardation of fatigue cracks following single tensile overloads are examined in a high-strength aluminium-lithium alloy 2090-T8E41, with specific emphasis on the role of fatigue crack closure. Mechanically, it is found that following the application of the overload, an immediate acceleration in fatigue crack growth is observed, which results from a reduction in (far-field) crack closure levels due to crack tip blunting. Subsequent crack growth retardation, as the crack penetrates the overload plastic zone, is associated with enhanced crack tip shielding prompted by compressive residual stresses ahead of the crack tip, crack deflection and consequent (near-tip) crack closure induced by asperity wedging in the immediate crack wake. Aluminum-lithium alloys, by virtue of their marked anisotropy and planar slip characteristics which promote meandering crack paths and hence high levels of shielding, are found to show large load interaction effects, and thus rank superior to other high strength aluminum alloys under tension-dominated variable amplitude loading spectra. However, under conditions where specimen surface layers are removed, or where cycling is performed at high (positive) load ratios, or involves compressive overload cycles (all processes which tend to limit the development of crack closure), the superior performance of aluminum-lithium alloys under variable amplitude fatigue loading may be compromised.
Sites of action for future therapy: an adenosine-dependent mechanism by which aspirin retains its antiinflammatory activity in cyclooxygenase-2 and NFκB knockout mice

Abstract The antiinflammatory action of aspirin is generally attributed to inhibition of cyclooxygenases 1 and 2, but additional mechanisms are at work. These include inhibition of NFκB translocation to the nucleus and the capacity of aspirin to promote accumulation of adenosine, a potent antiinflammatory autocoid. We tested these hypotheses in the murine air pouch model of acute inflammation in wild type mice and in cyclooxygenase 2 or NFκB knockouts. The antiinflammatory effects of aspirin, sodium salicylate and indomethacin did not correlate with inhibition of cyclooxygenase in either group. Indeed, aspirin retained its antiinflammatory properties even in COX-2 knockouts. Similarly, aspirin was no less antiinflammatory in mice rendered deficient for NFκB (p105) than in wild type controls. In contrast, dexamethasone lost its antiinflammatory capacity in NFκB knockouts. Aspirin and sodium salicylate dramatically increased concentrations of adenosine in exudates, a property shared with methotrexate and sulfasalazine. Removal of adenosine by adenosine deaminase or specific antagonism of adenosine at A 2 receptors completely reversed the antiinflammatory effects of aspirin and sodium salicylate, but not those of dexamethasone. This adenosine-dependent, antiinflammatory effect of aspirin points to another target of drug development.
Combinatorial approach to the edge delamination test for thin film reliability: concept and simulation

A high-throughput combinatorial approach to edge delamination test is proposed to map the failure of adhesion as a function of both temperature and film thickness in a single step. In this approach, a single specimen of a thin film bonded to a substrate with orthogonal thickness and temperature gradients is subdivided into separate samples. This approach can be adopted to measure the adhesion reliability for films with thicknesses in the nano regime by the addition of an overlayer. In addition, it can increase the pace of material innovations in nanoscale science and technology. The experimental requirements for a valid combinatorial test are analyzed using three-dimensional computational fracture mechanics. A simulation result is presented to demonstrate the feasibility of the combinatorial approach and to design the experimental protocol.
A fast-neutron spectrometer for reactor environments

Abstract A fast-neutron spectrometer which can operate in a reactor environment has been tested in the water shield of the Bulk Shielding Reactor I in gamma-ray fluxes as high as 10 6 R/h. Basically, the spectrometer consists of a very thin layer of 6 LiF between, but not in contact with, two silicon-gold diodes. Neutrons traversing the spectrometer collimator strike the 6 Li foil, and the alpha particle and triton emitted in the resulting 6 Li(n,α)T reaction ( Q = 4.78 MeV) are detected in coincidence in the two diodes. Shadow shielding in the collimator protects the diodes from direct reactor radiations. Background measurements are made by substituting a 7 LiF foil for the sensitive 6 LiF element. The measured spectra are in good agreement with calculated spectra, the measurements and calculations having been normalized to the same absolute neutron source intensity.
High performance metal-supported solid oxide fuel cells fabricated by thermal spray

Abstract Metal-supported solid oxide fuel cells (SOFCs) have been fabricated and characterized in this work. The cells consist of porous NiO–SDC as anode, thin SDC as electrolyte, and SSCo as cathode on porous stainless steel substrate. The anode and electrolyte layers were consecutively deposited onto porous metal substrate by thermal spray, using standard industrial thermal spray equipment, operated in an open-air atmosphere. The cathode materials were applied to the as-sprayed half-cells by screen-printing and heat-treated at 800 °C for 2 h. The cell components and performance were examined by scanning electron microscopy (SEM), X-ray diffraction, leakage test, ac impedance and electrochemical polarization at temperatures between 500 and 700 °C. The half-inch button cells exhibit a maximum power density in excess of 0.50 W cm −2 at 600 °C and 0.92 W cm −2 at 700 °C operated with humidified hydrogen fuel, respectively. The half-inch button cell was run at 0.5 A cm −2 at 603 °C for 100 h. The cell voltage decreased from 0.701 to 0.698 V, giving a cell degradation rate of 4.3% kh −1 . Impedance analysis indicated that the cell degradation included 4.5% contribution from ohmic loss and 1.4% contribution from electrode polarization. The 5 cm × 5 cm cells were also fabricated under the same conditions and showed a maximum power density of 0.26 W cm −2 at 600 °C and 0.56 W cm −2 at 700 °C with dry hydrogen as fuel, respectively. The impedance analysis showed that the ohmic resistance of the cells was the major polarization loss for all the cells, while both ohmic and electrode polarizations were significantly increased when the operating temperature decreased from 700 to 500 °C. This work demonstrated the feasibility for the fabrication of metal-supported SOFCs with relatively high performance using industrially available deposition techniques. Further optimization of the metal support, electrode materials and microstructure, and deposition process is ongoing.
Atmospheric transparency at Flagstaff, Arizona, 1972–1996: Baselines and Volcanic episodes compared

We present a summary of measurements of the atmospheric transparency over Flagstaff, Arizona, USA, made from 1972 to 1996. This period includes two major volcanic eruptions and two periods we believe are free from volcanic influence. The two eruptive periods show general similarity in history, although some differences are noted. Comparison of the two “clear” periods shows some deterioration in the tranparency over Lowell Observatory on a time scale of a decade.
A first-class approach to genericity

This paper describes how to add first-class generic types---including mixins---to strongly-typed OO languages with nominal subtyping such as Java and C#. A generic type system is "first-class" if generic types can appear in any context where conventional types can appear. In this context, a mixin is simply a generic class that extends one of its type parameters, e.g., a class C that extends T. Although mixins of this form are widely used in Cpp (via templates), they are clumsy and error-prone because Cpp treats mixins as macros, forcing each mixin instantiation to be separately compiled and type-checked. The abstraction embodied in a mixin is never separately analyzed.Our formulation of mixins using first-class genericity accommodates sound local (class-by-class) type checking. A mixin can be fully type-checked given symbol tables for each of the classes that it directly references---the same context in which Java performs incremental class compilation. To our knowledge, no previous formal analysis of first-class genericity in languages with nominal type systems has been conducted, which is surprising because nominal subtyping has become predominant in mainstream object-oriented programming languages.What makes our treatment of first-class genericity particularly interesting and important is the fact that it can be added to the existing Java language without any change to the underlying Java Virtual Machine. Moreover, the extension is backward compatible with legacy Java source and class files. Although our discussion of a practical implementation strategy focuses on Java, the same implementation techniques could be applied to other object-oriented languages such as C# or Eiffel that support incremental compilation, dynamic class loading, and nominal subtyping.
Beyond Home and Return: Negotiating Religious Identity across Time and Space through the Prism of the American Experience

To understand the social fields with which the children of immigrants actually identify, we interrogate the multiple sites and sources which Gujarati-origin Indian American Hindus and Muslims draw upon to construct their religious identities. We find that our respondents create religious selves by combining their imaginings of their parents’ religious upbringing with their own real and imagined experiences of religious life in the US, India, and other salient places around the world. They also incorporate real and perceived understandings of US religious traditions in four broad patterns which we call American-centric, Indian-centric, global-secular and global-religious. But while they adopt these various stances, they do so from their positions in the US. The circulation of religious ideas, practices and objects is filtered through uniquely American cultural structures and traverses uniquely American organizational channels.
Study on Edge Contact Area and Surface Integrity of Workpiece in Point Grinding Process

During cylindrical grinding process, the geometric configuration and size of the edge contact area between the grinding wheel and workpiece have the heavy effects on the workpiece surface integrity. In consideration of the differences between the point grinding and the conventional high speed cylindrical grinding, the geometric and mathematic models of the edge contact area in point grinding were established. Based on the models, the numerical simulation for the edge contact area was performed. By means of the point grinding experiment, the effect mechanism of the edge contact area on the ground surface integrity was investigated. These will offer the applied theoretic foundations for optimizing the point grinding angles, depth of cut, wheel and workpiece speed, geometrical configuration and size of CBN wheel and some other grinding parameters in point grinding process.
Relationships Among pH, Osmolality, and Concentration of Fixative Solutions

This report contains graphs that relate molarity with pH and osmolality (as measured by freezing point depression) for 5 buffer systems that are commonly used in preparing fixatives for electron microscopy, namely: cacodylate-HCl, s-collidine-HCl, Millonig's phosphate, Sorensen's phosphate, and veronal-acetate-HCl. In addition, osmolality is shown as a function of concentration for glutaraldehyde, OsO4, NaCl, glucose, sucrose, and CaCl2. These data provide simple guides for the design of buffered fixatives of any desired pH and tonicity. Osmolality cannot generally be calculated accurately from theory because of the partial ionization and aggregation of the concentrated solutions used. Commercially available glutaraldehyde often contains impurities which may increase its osmolality.
n-Type transition metal oxide as a hole extraction layer in PbS quantum dot solar cells.

The n-type transition metal oxides (TMO) consisting of molybdenum oxide (MoOx) and vanadium oxide (V2Ox) are used as an efficient hole extraction layer (HEL) in heterojunction ZnO/PbS quantum dot solar cells (QDSC). A 4.4% NREL-certified device based on the MoOx HEL is reported with Al as the back contact material, representing a more than 65% efficiency improvement compared with the case of Au contacting the PbS quantum dot (QD) layer directly. We find the acting mechanism of the hole extraction layer to be a dipole formed at the MoOx and PbS interface enhancing band bending to allow efficient hole extraction from the valence band of the PbS layer by MoOx. The carrier transport to the metal anode is likely enhanced through shallow gap states in the MoOx layer.
The Future of Research Methods in Africana Studies Graduate Curriculum

This study examines the state of research methods in Africana studies. In addition, the role that courses on research methods play in Africana Studies departments is also explored. Content analysis of departmental course offerings and descriptions reveal that half of graduate level degrees granting Africana Studies programs offer departmental courses on research methods. Moreover, the majority of the programs that offer courses on research methods focus primarily on qualitative methods of research. Correcting the quantitatively skewed content and general underrepresentation of research methods will help Africana Studies to produce more effective and well-prepared social engineers and scholar activists of the African experience.
Geochemical controls of elevated arsenic concentrations in groundwater, Ester Dome, Fairbanks district, Alaska

Abstract Ester Dome, an upland area near Fairbanks, Alaska, was chosen for a detailed hydrogeochemical study because of the previously reported elevated arsenic in groundwater, and the presence of a large set of wells amenable to detailed sampling. Ester Dome lies within the Fairbanks mining district, where gold-bearing quartz veins, typically containing 2–3 vol.% sulfide minerals (arsenopyrite, stibnite, and pyrite), have been mined both underground and in open cuts. Gold-bearing veins on Ester Dome occur in shear zones and the sulfide minerals in these veins have been crushed to fine-grained material by syn- or post-mineralization movement. Groundwater at Ester Dome is circumneutral, Ca–HCO 3 to Ca–SO 4 type, and ranges from dilute (specific conductance of 48 µS/cm) to more concentrated (specific conductance as high as 2070 µS/cm). In general, solute concentrations increase down hydrologic gradient. Redox species indicate that the groundwaters range from oxic to sub-oxic (low dissolved oxygen, Fe(III) reduction, no SO 4 reduction). Waters with the highest Fe concentrations, as high as 10.7 mg/L, are the most anoxic. Dissolved As concentrations range from 3 , Mo, F, or U) such that desorption of arsenic from clays or oxides also does not control arsenic mobility. Oxidation of arsenopyrite and dissolution of scorodite, in the near-surface environment appears to be the primary control of dissolved As in this upland area. More specifically, the elevated As concentrations are spatially associated with sulfidized shear zones and localities of gold-bearing quartz veins. Consistent with this interpretation, elevated dissolved Sb concentrations (as high as 59 µg/L), also correlated with occurrences of hypogene sulfide minerals, were measured in samples with high dissolved As concentrations.
Negative and Positive Factors Associated With the Well-Being of Lesbian, Gay, Bisexual, Transgender, Queer, and Questioning (LGBTQ) Youth

Factors associated with the well-being of lesbian, gay, bisexual, transgender, queer, and questioning (LGBTQ) youth were qualitatively examined to better understand how these factors are experienced from the youths' perspectives. Largely recruited from LGBTQ youth groups, 68 youth participated in focus groups (n = 63) or individual interviews (n = 5). The sample included 50% male, 47% female, and 3% transgender participants. Researchers used a consensual methods approach to identify negative and positive factors across 8 domains. Negative factors were associated with families, schools, religious institutions, and community or neighborhood; positive factors were associated with the youth's own identity development, peer networks, and involvement in the LGBTQ community. These findings suggest a pervasiveness of negative experiences in multiple contexts, and the importance of fostering a positive LGBTQ identity and supportive peer/community networks. Efforts should work towards reducing and eliminating the prejudicial sentiments often present in the institutions and situations that LGBTQ youth encounter.
Heat transfer investigations for in-bed and freeboard vertical U-tubes in a fluidized bed at moderate temperatures

Abstract The heat transfer coefficients for a single U-tube immersed vertically in fluidized beds of silica sands ( d p = 222, 488, and 778 μ m ) and for a bundle of six hair-pin shaped nested vertical tubes mounted in the freeboard have been measured as a function of fluidizing velocity at bed temperatures ranging from 365 to 535 K. Simultaneous measurements of bed voidage were also made in each case. The effects of bed temperature, fluidizing velocity and particle size on in-bed and freeboard heat transfer coefficients and voidage are examined and explained.
A System for Genetic Change in Apomictic Eastern Gamagrass

The ability of a species to undergo genetic change is a necessary component of its adaptive evolution, which can lead to the widening or narrowing of its genetic base. In diplosporous apomictic species, change through sexual or meiotic means is limited or omitted entirely. The objective of this study was to investigate the reproductive attributes of tetraploid apomictic eastern gamagrass, Tripsacum dactyloides var. dactyloides (L.) L. One-hundred progeny generated from an apomictic tetraploid eastern gamagrass accession were evaluated at a phenotypic, cytogenetic, and molecular level by means of random amplified polymorphic DNA (RAPD) procedures to detect their genetic relatedness to the maternal parent and to each other. Differences in phenotype and RAPD-PCR (polymerase chain reaction) banding profiles, followed by chromosome counts, revealed the generation of new tetraploid variants. The identification of genetic variation in tetraploid progeny would presumably indicate the production of hybrid individuals generated from the fertilization of a reduced egg cell by a sperm nuclei. However, this study indicates the complete omission of hybrid individuals generated from expected normal sexual behaviors and suggests the observed variation is generated by an incomplete or dysfunctional sexual process. The incidence of this behavior was 4%. The detection and generation of genetically variable but cytologically stable tetraploids, from an apomictic eastern gamagrass, suggests the presence of an additional mechanism whereby this species routinely may undergo genetic change without the introduction of new germplasm.
Making Decisions about Hazardous Waste Remediation When Even Considering a Remediation Technology Is Controversial

This paper investigates the circumstances under which proposed hazardous waste remediation technologies are socially acceptable, that is, considered seriously as options in a public arena. First, it summarizes a conceptual framework that guides investigation and interpretation of site-specific remediation decision-making. Second, it describes an initial application of that framework to the public participation venue of U.S. DOE Site-Specific Advisory Boards. Investigating the attributes of involved parties and of site context highlights technology acceptability as social decision-making that involves technical and technological issues rather than as a process driven by the technology itself.
Modeling Leakage With Mica-Based Compressive Seals for Solid Oxide Fuel Cells

Fuel cells represent a promising energy alternative to the traditional combustion of fossil fuels. In particular, solid oxide fuel cells (SOFCs) have been of interest due to their high energy densities and potential for stationary power applications. One of the key obstacles precluding the maturation and commercialization of planar SOFCs has been the lack of a robust sealant. This paper presents a computational model of leakage with the utilization of mica-based compressive seals. A finite element model is developed to ascertain the macroscopic stresses and deformations in the interface. In conjunction with the finite element model is a microscale contact mechanics model that accounts for the role of surface roughness in determining the mean interfacial gap at the interface. An averaged Reynolds equation derived from mixed lubrication theory is applied to model the leakage flow across the rough, annular interface. The composite model is applied as a predictive tool for assessing how certain physical parameters (i.e., seal material composition, compressive applied stress, surface finish, and interfacial conformity) affect seal leakage rates.Copyright © 2006 by ASME
Jet impingement drying of a moist porous solid

Abstract This paper investigates the thermal characteristics of a continuous industrial drying process for semi-porous textile composites. The conservation of mass, momentum and energy are written for a partially saturate porous fiber layer attached to a solid-backing layer. The numerical solution of the one-dimensional and transient conservation equations provides the temperature, volumetric saturation and gas phase pressure distributions in the moist porous solid and the temperature distribution in the solid-backing layer. During the wet region drying period, continuous liquid exists in the pore space, the moisture transport within the solid is described by the Darcy form of the momentum equation. The moisture transport in the sorption region is described by a bound liquid diffusion and gas phase transport. For the jet impingement type dryer, it is assumed that the penetration of the flow field into the porous solid is small (assumed valid due to the presence of the solid backing). The enhanced transport coefficients at the drying surface are estimated with the use of the Kolmogoroff theory of isotropic turbulence. This theory provides correlations for the heat and mass transfer coefficients from the fluid properties and the turbulent energy dissipation rate in the fluid. The model results of the continuous industrial drying process are compared to independent experimental temperature and global moisture content measurements taken in an operational industrial dryer. From the model analysis and experimental data, the heat flux conditions at the drying surface dictate the manner in which the solid is dried. The heat transfer coefficients considered are in the range of 20–130 W m−2K−1 and necessarily affect the manner in which moisture transport occurs within the solid. It is seen that the lower heat transfer coefficients more accurately represent the internal transport phenomena occurring during the drying process and the heating of the solid. The transport coefficients are compared to previously obtained empirical results.
Optimization of Tool Handle Shape for a Target User Population

One goal of Designing for Human Variability (DfHV) is to optimize the interaction between user and device. Often, this interaction is dictated by the spatial dimensions or shape of the artifacts with which people interact. A novel approach that applies DfHV principles including virtual fitting trials to optimize the shape of an artifact is presented and applied to the design of a tool handle. By breaking the problem apart into discrete blocks, called the hand model and tool model, application of standard optimization techniques is facilitated. The benefits of the approach include the ability to consider handles with variable cross-sections and to systematically consider the effects of multiple sizes. The methodology presented here is configurable for any given population and may be applied to other DfHV design problems.Copyright © 2009 by ASME