Electropolishing of nickel and cobalt in deep eutectic solvents

Electropolishing is a common method for decreasing surface roughness and removing surface irregularities. In this paper the electropolishing of nickel and cobalt are successfully demonstrated in a deep eutectic solvent, comprising a 2:1 molar mixture of ethylene glycol and choline chloride. Voltammetric and electrochemical impedance studies were used to characterise the polishing mechanism and show that film formation occurs prior to polishing. Scanning electron microscopy and atomic force microscopy were used to characterise the morphology before and after polishing and 3D optical microscopy was used in-situ to observe film formation during polishing. This study shows that the impact of film formation and subsequently mass transport are responsible for electropolishing of both metals in the choline chloride-based ionic liquid.     

Bidimensional measurement of acculturation in a multiethnic community sample of first-generation immigrants.

Despite the rapid growth of the acculturation research literature in recent years, few studies have examined acculturation among community samples of immigrants in Canada. The present study used a bidimensional approach to examine acculturation among Anglophone Caribbean (n = 109), Vietnamese (n = 97), and Filipino (n = 109) first-generation immigrant adults living in a diverse urban community in Montreal, Quebec, Canada. Heritage and mainstream cultural orientations were independently assessed in 3 domains of acculturation: loyalty, behaviour, and situated identity. Across the 3 domains and the 3 groups, the 2 cultural orientations were largely independent, though in the Vietnamese and Filipino samples heritage group loyalty was positively related to mainstream group loyalty. Overall, results support a bidimensional model of acculturation and suggest the value of separately assessing different acculturation domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A simple method for calculating winding temperature gradient in power transformers

This paper presents a new method for calculating winding temperature gradient in large power transformers. A general formulation of the problem is made using the electrical analogy. An expression for the thermal resistance of the solid insulation is found using analytical methods. Expressions for the thermal resistance of the oil boundary layer for natural and directed oil flow are then found through correlation of test results from actual transformers. A comparison of the results of the new method and previous methods is presented. The new method is found to be a significant improvement.     

Proving relative lower bounds for incremental algorithms

Summary A general method that permits simple proofs of relative lower bounds for incremental update algorithms is presented. This method is applied to classify functions by relative lower bounds. We demonstrate our technique by bounding a number of incremental algorithms drawn from various domains. The method described expands upon work by Paull, Berman, and Cheng [PCB] and generalizes a result of Even and Gazit [EG]. Our results have interesting implications with respect to the optimality of an incremental algorithm previously developed by Ryder in [R, RP2]. Perhaps most importantly, the proof method and function classification suggest which types of problems are likely to yield good incremental algorithms (i.e., of lower complexity) and which cannot be improved by an incremental approach.     

A critical analysis of incremental iterative data flow analysisalgorithms

A model of data flow analysis and fixed point iteration solution procedures is presented. The faulty incremental iterative algorithm is introduced. Examples of the imprecision of restarting iteration from the intraprocedural and interprocedural domains are given. Some incremental techniques which calculate precise data flow information are summarized     

Abnormal hemoglobins in a quarter million people

Hemolysates of erythrocytes from more than a quarter million people in Alabama were electrophoresed on cellulose acetate, pH 8.4, and those samples exhibiting an abnormality were also electrophoresed in citrate agar, pH 6.0. The globin chains of mutants other than Hb S and C were electrophoresed in urea-mercaptoethanol buffers at both pH 8.9 and pH 6.0, and 60 of them were also analyzed structurally. Of about 6000 samples from whites, only three contained abnormal hemoglobins--Hb D Los Angeles, Hb J Baltimore, and one unidentified. Of 249,000 samples from blacks, about 29,000 contained electrophoretically detectable abnormalities, most of them associated with Hb S or C, present in a frequency of about 9% and 3%, respectively. About 1000 samples resolved into patterns of potential clinical significance. Twenty other mutant hemoglobins were detected, in various genetic combinations in 164 kindreds; four of these-Hb Alabama, Montgomery, Titusville, and Mobile--were previously unknown. The methods used are rapid, economical, and well suited for large scale surveys. They provide highly specific characterizations of many mutant hemoglobins, and no discrepancies were found between the presumptive identifications based on these characterizations and the definitive identifications obtained from structural analyses.     

The pfort verifier

The PFORT Verifier is a program which checks a FORTRAN program (i.e. a main program and a set of subprograms) for adherence to a large, carefully defined, portable subset of American National Standard FORTRAN called PFORT. Unlike many FORTRAN implementations, the Verifier diagnoses errors in interprogram-unit communication through argument lists and COMMON. The Verifier is itself written in PFORT and has been installed on a variety of computers. This paper describes the development of PFORT and the Verifier. A detailed definition of PFORT noting its differences from ANS FORTRAN is included.     

Evaluation of acridine in Nafion as a fluorescence-lifetime-based pH sensor

We report a novel fluorescence-lifetime-based pH sensing method that utilizes acridine incorporated into Nafion (AcNaf) as the fluorescent indicator. The AcNaf sensor is excited using a 380 nm light emitting diode (LED) and the fluorescence lifetimes are measured at 450 and 500 nm. The fluorescence behavior of acridine as a function of pH in aqueous phosphate buffers and incorporated into the Nafion membrane has been investigated. The results show that incorporating acridine into Nafion changes the apparent ground-state pKa from -5.45 to -9, while the apparent excited-state pKa* is only slightly changed (approximately 9.4 in 0.1 M phosphate buffer). The AcNaf film shows a good pH response with a change in average lifetime of approximately 19 ns (at an emission wavelength of 450 nm) over the pH 8 to 10 range. We also show that excited-state protonation does not occur in the AcNaf sensor film and that chloride quenching cannot occur because of the permselective nature of Nafion. We also discuss how the unique structure of Nafion affects the fluorescence behavior of acridine at various pH values and examine the impact of buffer concentration on apparent pKa and pH sensing ability.     

Hierarchical Temporal Memory Continuous Learning Algorithms for Fire State Determination

Fire Technology - An ultimate goal of placing fire detection systems in buildings and structures is to allow for the rapid detection of fire and accurate faster than real time prediction of ensuing...     

Fluorescence excitation-emission matrix (EEM) spectroscopy for rapid identification and quality evaluation of cell culture media components

The application of fluorescence excitation-emission matrix (EEM) spectroscopy to the quantitative analysis of complex, aqueous solutions of cell culture media components was investigated. These components, yeastolate, phytone, recombinant human insulin, eRDF basal medium, and four different chemically defined (CD) media, are used for the formulation of basal and feed media employed in the production of recombinant proteins using a Chinese Hamster Ovary (CHO) cell based process. The comprehensive analysis (either identification or quality assessment) of these materials using chromatographic methods is time consuming and expensive and is not suitable for high-throughput quality control. The use of EEM in conjunction with multiway chemometric methods provided a rapid, nondestructive analytical method suitable for the screening of large numbers of samples. Here we used multiway robust principal component analysis (MROBPCA) in conjunction with n-way partial least squares discriminant analysis (NPLS-DA) to develop a robust routine for both the identification and quality evaluation of these important cell culture materials. These methods are applicable to a wide range of complex mixtures because they do not rely on any predetermined compositional or property information, thus making them potentially very useful for sample handling, tracking, and quality assessment in biopharmaceutical industries.