cssi/SciSciGPT-SciSciNet huggingface dataset:
Preparation and magnetic filtration of polyacrylamide gels containing covalently ommobilized proteins and a ferrofluid

Abstract Adenylate kinase, acetate kinase, and horseradish peroxidase have been immobilized covalently in good yields (20–90%) by free radical copolymerization of acrylamide, N,N'-methylenebisacrylamide, and N-acryloxysuccinimide, in a solution containing enzyme and enzyme-protecting reagents (substrates, DTT). To establish the sequence of events responsible for the formation of these enzyme-containing gels, rates for the reactions of N-acryloxysuccinimide and N-acetoxysuccinimide with oxygen-, nitrogen-, and sulfur- containing nucleophiles were determined. These data suggest that the rate of acylation of lysine ϵ-amino groups by N-hydroxysuccinimide-active esters is such that acylation and polyacrylamide gel formation are concurrent in the experiment procedures used. The yield of active, covalently-immobilized enzyme obtained by this procedure depends critically on active ester concentration and pH. To facilitate separation of these enzyme-containing gels from suspension, a ferrofluid — a surfactant-stabilized magnetite colloid — has been entrapped in them. The resulting magnetic gels can be manipulated using either conventional magnetic filtration and containment techniques, or more effective high-gradient procedures. Suspension polymerization can be used to produce spherical magnetic beads. The choice of suspending medium (a thixotropic carbon tetrachloride—n-heptane—silanized fumed silica mixture) and surface active agent (lecithin) are crucial to the success of this polymerization procedure.
UV photolysis, organic molecules in young disks, and the origin of meteoritic amino acids

Abstract The origin of complex organic molecules such as amino acids and their precursors found in meteorites and comets is unknown. Previous studies have accounted for the complex organic inventory of the Solar System by aqueous chemistry on warm meteoritic parent bodies, or by accretion of organics formed in the interstellar medium. This paper proposes a third possibility: that complex organics were created in situ by ultraviolet light from nearby O/B stars irradiating ices already in the Sun’s protoplanetary disk. If the Sun was born in a dense cluster near UV-bright stars, the flux hitting the disk from external stars could be many orders of magnitude higher than that from the Sun alone. Such photolysis of ices in the laboratory can rapidly produce amino acid precursors and other complex organic molecules. I present a simple model coupling grain growth and UV exposure in a young circumstellar disk. It is shown that the production may be sufficient to create the Solar System’s entire complex organic inventory within 106 yr. Subsequent aqueous alteration on meteoritic parent bodies is not ruled out.
Molecular dynamics simulation of ice XII

Abstract Molecular dynamics simulations have been performed on the newly discovered metastable ice XII. This new crystalline ice phase [C. Lobban, J.L. Finney, W.F. Kuhs, Nature (London) 391 (1998) 268] is proton-disordered. Thus 90 possible configurations of the unit cell can be constructed which differ only in the orientations of the water molecules. The simulation used the TIP4P potential model for water at constant temperature and density. About one-quarter of the initial configurations did not melt in the course of the simulation. This result is supportive of the experimental structure and also demonstrates the ability of this water model to study ice phases.
An assessment of international college student adjustment

International students have realistic expectations about their adjustment to college, however, they seem to experience a more difficult transition than U.S. students. Scores on the Student Adaptation to College Questionnaire for international and U.S. students are compared. The results indicated that international students scored significantly lower on the social and the institutional attachment and goal commitment subscales. The Student Adaptation to College Questionnaire may have applications in targeting international student needs.
SU‐E‐J‐199: Evaluation of Motion Tracking Effects On Stereotactic Body Radiotherapy of Abdominal Targets

Purpose: To evaluate the effects of respiratory motion on the delivered dose distribution of CyberKnife motion tracking-based stereotactic body radiotherapy (SBRT) of abdominal targets. Methods: Four patients (two pancreas and two liver, and all with 4DCT scans) were retrospectively evaluated. A plan (3D plan) using CyberKnife Synchrony was optimized on the end-exhale phase in the CyberKnife's MultiPlan treatment planning system (TPS), with 40Gy prescribed in 5 fractions. A 4D plan was then created following the 4D planning utility in the MultiPlan TPS, by recalculating dose from the 3D plan beams on all 4DCT phases, with the same prescribed isodose line. The other seven phases of the 4DCT were then deformably registered to the end-exhale phase for 4D dose summation. Doses to the target and organs at risk (OAR) were compared between 3D and 4D plans for each patient. The mean and maximum doses to duodenum, liver, spinal cord and kidneys, and doses to 5cc of duodenum, 700cc of liver, 0.25cc of spinal cord and 200cc of kidneys were used. Results: Target coverage in the 4D plans was about 1% higher for two patients and about 9% lower in the other two. OAR dose differences between 3D and 4D varied among structures, with doses as much as 8.26Gy lower or as much as 5.41Gy higher observed in the 4D plans. Conclusion: The delivered dose can be significantly different from the planned dose for both the target and OAR close to the target, which is caused by the relative geometry change while the beams chase the moving target. Studies will be performed on more patients in the future. The differences of motion tracking versus passive motion management with the use of internal target volumes will also be investigated.
Engineering plastics from lignin, 23. Network formation of lignin-based epoxy resins

The network-forming behavior, gelation, and vitrification of lignin-polyether-copolymer-epoxide/amine resins were determined using a recently described dynamic mechanical thermal analysis (DMTA)-based method. Six resins were studied which differed in lignin content, polyether arm length, and molecular weight. Glass transition temperature (Tg)-cure time master curves could be constructed for cure temperatures ranging from 90 to 200°C; and semiexperimental vitrification plots were derived for each system based on the knowledge of activation energy and cure time at a reference temperature. The point at which the cure process becomes diffusion-controlled (i.e., vitrification) happens at lower extents of conversion for lignin-rich fractions. Near vitrification, the cure events change from n-th- to second-order kinetics, and this indicates a reduction in polyether-arm mobility. This suggests that the crosslinking of lignin centers with polyether arms produces a network in which the reactant-carrying flexible arms do not have sufficient free volume to react. The greatest increase in Tg during crosslinking is about 100°C for all molecular weight fractions, and this suggests that high-Tg networks can only be achieved with high-Tg prepolymers.
Predicting currency exchange rates by genetic programming with trigonometric functions and high-order statistics

This paper describes an extension of the traditional application of Genetic Programming in the domain of the prediction of daily currency exchange rates. In combination with trigonometric operators, we introduce a new set of high-order statistical functions in a unique representation and analyze each system performance using daily returns of the British Pound and Japanese Yen. We will demonstrate that the introduction of high-order statistical functions in combination with trigonometric functions will outperform other traditional models such as Genetic Programming with the basic function set and ARMA models. Performance will be measured on hit percentage, average percentage change, and profit.
A Review of Recommended Social Competency Programs for Students with Autism Spectrum Disorders

Social competency deficits are a core feature of autism spectrum disorders (ASDs). During the past several decades, a number of social skill interventions for students with ASD have emerged. However, over the past five years, three converging issues have brought increased attention to the need for social competence programming: (1) increased ASD incidence rates, (2) inclusion and integration trends, and (3) recent No Child Left Behind Act requirement regarding use of evidence-based practices. This article discusses current best practices in enhancing the social competence of learners with ASD. To this end, a review of the literature was conducted to: (1) define key behaviors related to social competence targeted by common interventions and (2) identify the core components and targets that are essential for effective social competence interventions. Searches done by hand and electronically were conducted to identify empirical reviews or summaries of effective social competence interventions from preschool ...
Lipid Content and Oxidation in Soy Protein/Ground Beef Mixture

The effects of varying proportions of textured soy protein (mixed with ground beef) on the evap orative loss, cooking yield, lipid content, lipid oxidation, and overall acceptability were studied in cooked patties containing 0 to 40 percent soy protein. All analyses were made of patties cooked immediately after thawing. Lipid oxidation determina tions were also made after 48 and 72 hours of refrigeration. The results showed that when com pared to all beef patties the cooking yield was significantly (p<0.05) higher for those containing 30 and 40 percent soy, and the evaporative loss was lower (p<0.05) for the patties containing 40 percent soy. Total lipid content was significantly less (p<0.05) in all samples containing soy protein. Compared to 100 percent ground beef, there was less (p<0.05) fat oxidation in samples containing 30 percent soy which were refrigerated 48 and 72 hours, and in samples containing 40 percent soy refrigerated 48 hours. Overall acceptability was lower for all soy protein/beef patties as compared to those made of 100 percent beef (p<0.05).
Geometrical analysis of inclusions in rat liver cells as seen in electronmicrograms.

It is being shown by the application of statistico-geometrical criteria that: 1. The double lines seen in electronmicrograms of rat liver cells are sections of bands 400 A thick, 8000 A wide and of extreme length. 2. The spherical mitochondria in rat liver cells range: in diameter between 0·8 μ, and 2·0 μ in surface between 2·0 μ2 and 12/6 μ2 in volume between 0·27 μ3 and 4.19 μ3
Localized wave transmission physics and engineering

1407_41Several exact, nonseparable, space-time solutions of the scalar wave and Maxwell's equations have been found recently. These localized wave (LW) solutions contain very broad-bandwidth components and can be optimized to exhibit enhanced localization properties. Moreover, by driving an array with these LW solutions, one can generate beams that also exhibit these LW characteristics. A new type of array is required to try to realize these localized wave effects -- one that has independently addressable elements. The enhanced localization effects are intimately coupled to the proper spatial distribution of broad-bandwidth signals driving the array; i.e., by shading not only the amplitudes, but also the frequency spectra of the pulses driving the array. A LW pulse-driven array generates a moving localized, interference pattern, i.e., a set of pulses whose shapes are reconstituted as they propagate by the frequency components arriving at different times from the various aperture sources. Analytical bounds on the characteristics of beams generated by an arbitrary pulse-driven array have been derived and are supported by numerical and experimental values. These bounds extend the meaning of near-field distances or diffraction lengths to the situation where the array driving functions can be broad-bandwidth signals. It has been demonstrated theoretically and experimentally that an acoustic array driven with a designed set of localized wave (LW) solutions of the scalar wave equation generates a robust, well-behaved, transient pencil-beam of ultrasound in water that outperforms the beams generated by related continuous wave excitations of the same array. Numerical models predict similar results for an electromagnetic LW pulse-driven array.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Optimization of converging-beam grating monochromators.

Design principles for the optimization of a version of the Monk–Gillieson grating monochromator are developed. Third-order aberrations for coma and astigmatism are both compensated for one wavelength, which can be chosen as wanted. The general relations for the orientations of the imaging mirror and the plane grating, with respect to each other and to the light-bundle axis for correct compensation of imaging errors, are developed. Expressions are given for the residual aberrations at other than the compensated wavelength. The results are applied to a typical mirror–grating combination.
Effect of Oxygen Breathing on Pacing-Induced Angina Pectoris and other Manifestations of Coronary Insufficiency

Eleven patients with arteriographically confirmed coronary artery disease and normal arterial oxygen saturation were studied. The angina threshold was determined first by successive elevation of heart rate at increments of 10 and 5 beats/min by right atrial pacing while the patients were breathing air via a close-fitting mask. The mask was then connected to an oxygen tank without the patient's knowledge. After 5 min of oxygen breathing, the heart rate was again raised to the previously determined threshold level. In nine of 11 patients angina did not recur. The absence of angina was associated with improvement in myocardial lactate extraction from -17 ± 15 to +18 ± 10% (P < 0.025), in S-T abnormalities in six of seven patients, and in pulsus alternans in three of five patients. The pacing rate was then raised at increments of 5 beats/min until angina recurred. With oxygen breathing, angina developed at higher pacing rates (129 ± 7 beats/min with air and 137 ± 6 beats/min with oxygen, on the average; P < 0...
Unobtrusively tracking mammographers' eye gaze direction and pupil diameter

We developed techniques to unobtrusively track direction and pupil diameter of radiologists reading a wide variety of films. This study concentrated on mammography since the use of mammograms is important for successful treatment of breast cancer, and we wished to determine how previous studies of eye gaze with lung films relate to the specialized field of mammography. Our objective was to identify eye gaze patterns in mammographic experts as they observe features, such as masses and microcalcification clusters: identification of these patterns could lead to improving the rate of early detection of breast cancer. Our near IR light system successfully tracked eye gaze direction and pupil diameter of mammographic experts evaluating films. The association of long eye gaze dwells with diagnostic accuracy varied with the type of object being viewed. In films with masses, false positive diagnoses were associated with long dwells: this is similar to published results of observing lung nodule diagnosis. In mammograms with microcalcifications, true positive diagnoses were associated with long dwells. The association of prolonged dwells with true positive diagnoses of microcalcifications is a new observation.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Plasmonic coupling interference: a new approach for cancer diagnostics using SERS detection

We have developed a novel label-free approach referred to as plasmonic coupling interference (PCI) nanoprobes for nucleic acid detection using surface-enhanced Raman scattering (SERS). To induce a strong plasmonic coupling effect and SERS signal, a nano-network of silver nanoparticles having the Raman label located between adjacent nanoparticles is assembled by Raman-labeled nucleic acid duplexes. The PCI method then utilizes specific nucleic acid sequences of interest as competitor elements of the Raman-labeled DNA probes to interfere the formation of the nucleic acid-crosslinked nano-networks in a competitive binding process, resulting in a reduced SERS signal. We illustrate the potential of the PCI technique for biomedical applications by detecting single-nucleotide polymorphism (SNP) and microRNA sequences involved in breast cancers. The results of this study could lead to the development of nucleic acid diagnostic tools for biomedical diagnostics and biosensing applications using SERS detection.
NOVEL ROLE OF HUMAN CD4 MOLECULE IDENTIFIED IN NEURODEGENERATION

The human CD4 molecule (hCD4) is expressed on T lymphocytes and macrophages and acts as a key component of the cellular receptor for HIV. At baseline, hCD4 transgenic mice expressed hCD4 on microglia, the resident mononuclear phagocytes of the brain, and showed no neuronal damage. Activation of brain microglia by peripheral immune challenges elicited neurodegeneration in hCD4 mice but not in nontransgenic controls. In post-mortem brain tissues from AIDS patients with opportunistic infections, but without typical HIV encephalitis, hCD4 expression correlated with neurodegeneration. We conclude that hCD4 may function as an important mediator of indirect neuronal damage in infectious and immune-mediated diseases of the central nervous system.
An animal model for the measurement of acute tolerance to ethanol.

Abstract An apparatus is described for the measurement of acute tolerance to ethanol in small animals. Male, Sprague-Dawley rats were trained on the apparatus to leap to a descending platform to avoid being shocked. After an i.p. injection of 2 g/kg ethanol, the rats were tested repeatedly on the apparatus, and the plasma ethanol concentration was measured after each trial. The results demonstrated that the jumping ability of the rats was significantly more impaired during the ascending portion of the plasma ethanol curve than during the descending portion of the curve. Furthermore, it was demonstrated that the improvement in jumping ability during the descending portion of the curve was not dependent on a lowered plasma ethanol concentration. In a second experiment, the possibility of practice effects was eliminated by measuring the jumping ability and plasma ethanol concentration in one group of rats on the ascending portion of the plasma ethanol curve and in another group on the descending portion of the curve. A significant improvement in jumping ability was again observed during the descending portion of the curve, even though the plasma ethanol concentrations of the two groups were comparable. The development of acute tolerance to ethanol was thus demonstrated in both experiments.
Abstract PR-4: Genetic heterogeneity in colorectal cancer associations in African Americans

Background: Genome-wide association studies of colorectal cancer (CRC) have identified risk variants in 10 genomic regions. None of these studies included African Americans, who have the highest incidence and mortality from CRC in the U.S. For the 10 genomic regions, we performed an association study in African and European Americans. Methods: We genotyped 22 single nucleotide polymorphisms (SNPs) in DNA samples from 1194 patients with CRC (795 African Americans and 399 European Americans) and 1352 controls (985 African Americans and 367 European Americans). At chromosome 8q24.21 region 3, we analyzed five additional SNPs from 1000 African American cases and 1393 controls. Association testing was done using multivariate logistic regression controlling for ancestry, age, and sex. Results: Whereas effects sizes and directions of association for all SNPs tested in European Americans were consistent with previously published studies, the associations ran in the opposite direction for 9 of 22 SNPs tested in African Americans. Among African Americans, the SNP rs6983267 at 8q24.21 was not associated with CRC (OR=1.18; P=0.12); instead, the 8q24.21 SNP rs7014346 (OR=1.15; p=0.03) was associated with CRC in this population. On chromosome 15q13.3, rs10318 was associated with CRC in both populations. On chromosome 10p14, the opposite allele of rs10795668 was associated with CRC in African Americans (OR=1.35; P=0.04). On chromosome 11 q23.1, rs3802842 was significantly associated with rectal cancer risk only among African Americans (OR 1.34; P=0.01); a similar observation was made in previous studies of Europeans. Among European Americans, SNPs on chromosomes 8q24.21,11 q23.1, and 16q22.1 were associated with CRC, in agreement with previous reports. Conclusion: There is genetic heterogeneity in CRC associations in Americans of African vs. European descent. Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):PR-4.
SEROLOGICALLY DEFINED AND LYMPHOCYTE-DEFINED COMPONENTS OF THE MAJOR HISTOCOMPATIBILITY COMPLEX IN THE MOUSE

The mixed leukocyte culture (MLC) test is an in vitro model of the recognition phase of the homograft response. For the most part, activation in MLC is dependent on differences of the major histocompatibility complex (MHC). Our present studies in the mouse suggest that activation is primarily associated with differences of genetic regions of the MHC other than those which control the serologically defined (H-2) antigens. These differences do not lead to cytotoxic or agglutinating antibody formation despite extensive immunization; we have called these differences lymphocyte-defined (LD) differences. The strongest stimulation in MLC is associated with differences of the Ir region. It is possible that the Ir product is the T cell receptor and that it is this same molecule which can act as the stimulatory agent in MLC. Other possibilities are discussed.
Temperature and pH optima of extremely halophilic archaea: a mini-review

Archaeal microorganisms that grow optimally at Na+ concentrations of 1.7 M, or the equivalent of 10% (w/v) NaCl, and greater are considered to be extreme halophiles. This review encompasses extremely halophilic archaea and their growth characteristics with respect to the correlation between the extent of alkaline pH and elevated temperature optima and the extent of salt tolerance. The focus is on poly-extremophiles, i.e., taxa growing optimally at a Na+ concentration at or above 1.7 M (approximately 10% w/v NaCl); alkaline pH, at or above 8.5; and elevated temperature optima, at or above 50°C. So far, only a very few extreme halophiles that are able to grow optimally under alkaline conditions as well as at elevated temperatures have been isolated. The distribution of extremely halophilic archaea growing optimally at 3.4 M Na+ (approximately 20% w/v NaCl) is bifurcated with respect to pH optima, either they are neutrophilic, with a pHopt of approximately 7, or strongly alkaliphilic, with pHopt at or above 8.5. Amongst these extreme halophiles which have elevated pH optima, only four taxa have an optimum temperature above 50°C: Haloarcula quadrata (52°C), Haloferax elongans (53°C), Haloferax mediterranei (51°C) and Natronolimnobius‘aegyptiacus’ (55°C).
Deciphering the message in protein sequences: tolerance to amino acid substitutions

An amino acid sequence encodes a message that determines the shape and function of a protein. This message is highly degenerate in that many different sequences can code for proteins with essentially the same structure and activity. Comparison of different sequences with similar messages can reveal key features of the code and improve understanding of how a protein folds and how it performs its function.
Quantum jumps in the PEMFC science and technology from the 1960s to the year 2000 Part I. Fundamental scientific aspects

Abstract Proton exchange membrane fuel cells are at present in the forefront of all types of fuel cells because of the ‘quantum jumps’ in its technology since its application in the 1960s in NASAs Gemini space flights as an auxiliary power source. PEMFC technology since the 1960s highlights the ‘quantum jumps’ both in the fundamental areas of research (Part I) and in the engineering and technology and developmental (Part II), which are leading to the era of promising applications. This part of the review is on the ‘quantum jumps’ in the fundamental areas of research, which have enabled the rapid advances in the technology development, i.e. (i) transition from polystyrene sulfonic acid to perfluorosulfonic acid membranes; (ii) a 10- to 100-fold reduction in the platinum loading in electrode by using nanosize electrocatalyst particles supported on high surface area carbon and impregnation of the proton conducting electrolyte into the active layer of the electrode; (iii) optimization of structure of electrode and of membrane and electrode assembly to enhance power densities to 0.5–0.7 W cm −2 at desirable efficiencies; (iv) using perfluorosulfonic acid membranes for DMFCs instead of liquid electrolytes to attain reasonably good efficiencies and power densities. The vital scientific challenges needing resolution for further advances in the technology are also summarized.
Evolution of gene position: Chromosomal arrangement and sequence comparison of the Drosophila melanogaster and Drosophila virilis sina and Rh4 genes

Abstract The seven in absentia (sina) gene of Drosophila encodes a nuclear protein required for normal eye development. In Drosophila melanogaster, the sina gene is located within an intron of the Rh4 opsin gene. We examine here the nucleotide sequences and chromosomal arrangements of these genes in Drosophila virilis. An interspecies comparison between D. melanogaster and D. virilis reveals that the protein-coding sequences of the sina and Rh4 genes are highly conserved, but the relative chromosomal position and structural arrangement of these genes differ between the two species. In particular, the sina and Rh4 genes are widely separated in D. virilis, and there is no intron in the Rh4 gene. Our results suggest that the Rh4 gene was translocated to another chromosomal location by a retrotransposition event.
Real-Time Measurement of Multi-Component Velocity Vectors Within Abdominal Aortic Aneurysms Using Echo PIV: Comparison of In Vitro and Computational Results

Abdominal aortic aneurysms (AAAs) are localized balloon-shaped expansions commonly found in the infrarenal segment of the abdominal aorta, between the renal arteries and the iliac bifurcation. Abdominal aortic aneurysm rupture has been estimated to occur in as much as 3%–9% of the population, and represents the 13th leading cause of death in the United States, producing more than 10,000 deaths annually [1]. Thus, determining the significant factors for aneurysm growth and rupture has become an important clinical goal. From a biomechanical standpoint, AAA rupture risk is related to certain mechanical and hemodynamic factors such as localized flow fields and velocity patterns, and flow-induced stresses within the fluid and in the aneurysm structure [2]. Disturbed flow patterns at different levels have also been found to trigger responses within medial and adventitial layers by altering intercellular communication mechanisms. Thus, localized hemodynamics proximal, within and distal to AAA formations play an important role in modulating the disease process, and non-invasive and easy-to-implement methods to characterize and quantify these complex hemodynamics would be tremendously useful.Copyright © 2007 by ASME
Singularity spectrum of intermittent seismic tremor at Kilauea Volcano, Hawaii

Fractal singularity analysis (FSA) is used to study a 22-year record of deep seismic tremor (30–60 km depth) for regions below Kilauea Volcano on the assumption that magma transport and fracture can be treated as a system of coupled nonlinear oscillators. Tremor episodes range from 1 to 100 min (cumulative duration = 1.60×104 min; yearly average = 727 min yr−1; mean gradient = 24.2 min yr−1 km−1). Partitioning of probabilities, pi, in the phase space of normalized durations, xi, are expressed in terms of a function f(α), where α is a variable exponent of a length scale, l. Plots of f(α) vs. α are called multifractal singularity spectra. The spectrum for deep tremor durations is bounded by α values of about 0.4 and 1.9 at f = 0; fmax ≃ 1.0 for α ≃ 1. Results for tremor are similar to those found for systems transitional between complete mode locking and chaos.
Complex role of protein phosphorylation in gene activation by hypoxia.

Complex role of protein phosphorylation in gene activation by hypoxia. Mammalian cells are able to sense decreased oxygen tension in their environment and turn-on the expression of specific hypoxia responsive genes. The best studied of these hypoxia regulated genes is the one that encodes for erythropoietin, the glycoprotein hormone that regulates red cell production [1]. The response of the erythropoietin gene to hypoxia is mediated by an enhancer sequence located at the 3′ flanking region of the gene [2–4]. A hypoxia inducible DNA-binding protein complex, termed HIF-1, regulates the transcriptional function of the erythropoietin enhancer [5]. Most interestingly, identical HIF-1 complexes also control the responses of other hypoxia regulated genes, in what appears to be a general mechanism of oxygen sensing and response [6, 7]. These other hypoxia regulated genes include vascular endothelial growth factor, glycolytic enzymes such as pyruvate kinase and aldolase A, glucose transporter 1 and endothelin, among others. All these genes are transcriptionally activated by hypoxia and also by transition metals such as cobalt (Co) and by iron chelators such as desferrioxamine (Dfx) [reviewed in 8].
Application of the peroxidase anti-peroxidase system as an universal reagent for the two-site binding enzyme immunoassay

Abstract An indirect two-site binding enzyme immunoassay (EIA) is described, in which horse-radish peroxidase (HRP) is bound immunologically to anti-HRP IgG in the form of peroxidase anti-peroxidase complexes (PAP-complex). In this EIA both purified HRP and crude HRP had the same sensitivity due to the selective reaction of the monospecific anti-HRP IgG with the highly active HRP isoenzymes in both preparations. To obtain similar results the amount of crude HRP needed is 18 times higher than that of purified HRP. A comparison of differently composed PAP-complexes showed that only those formed in an excess of HRP yielded a highly sensitive EIA. Urea splitting of the PAP-complexes did not raise the specific activity of the enzyme. The PAP-complexes were used in an assay for quantification of the pregnancy-associated α 2 -glycoprotein and compared with an indirect two-site binding EIA, in which purified HRP was covalently bound to IgG. Both test variants resulted in the same sensitivity and showed similar precision.
Sudden cardiac death caused by migration of a TrapEase inferior vena cava filter: case report and review of the literature.

Case A 43-year-old female presented with sudden onset of palpitations, chest pain, and shortness of breath associated with hypoxemia. A helical computed tomography (CT) scan of the chest revealed a large saddle pulmonary embolism. Intravenous tPA relieved the shortness of breath and improved the hypoxemia. Inferior vena cava (IVC) filter (TrapEase, Cordis Corp., Miami, FL, USA) was placed. On day 6 of her hospitalization, she went into cardiopulmonary arrest while walking back from the rest room. The patient died despite a prolonged attempt at cardiopulmonary resuscitation. At that time, ventricular tachycardia and then ventricular fibrillation were recorded. Autopsy of the heart showed the IVC filter entrapped within the tricuspid valve. Discussion The incidence of IVC filter migration ranges from 0.3 to 6% with rare migration to the heart or lung (0.1–1.25%). Sudden cardiac death from migration of IVC filter is extremely rare. We report the first case of sudden cardiac death caused by migration of the TrapEase filter to the heart. There are two reports in the literature of death from migrating Greenfield and Antheor filters. Conclusion An IVC filter migration to the heart, although rare, can cause serious arrhythmia and sudden cardiac death. Copyright © 2008 Wiley Periodicals, Inc.
Restructuring Policy for America's Schools

It's time to restructure our change strategy, according to this writer, who argues that public education must be given the power to succeed.
Methods of defect-engineering shallow junctions formed by B+-implantation in Si

Control of dopant diffusion during high-temperature cycling is critical in forming shallow electrical junctions in silicon as needed in integrated-circuit manufacturing. However, junctions formed by implantation can be anomalously deep due to a transiency associated with ion-induced defects which greatly enhances dopant diffusion. The purpose of this work was to investigate methods of defect engineering the implantation process to control or eliminate transient-enhanced diffusion (TED). TED of boron has been attributed to excess interstitials introduced into the lattice during implantation, known as the plus-one model. Effects of pre-amorphization (i.e., amorphization prior to dopant implantation using isoelectric ions) on TED of boron, and particularly, the role of the end-of-range (EOR) defects at the amorphous-crystalline interface, are discussed. These EOR defects were varied by altering the implantation conditions during pre-amorphization. Also, other means of controlling the transiency are discussed, in particular, the use of high-energy ions to introduce excess vacancies into the lattice where dopant diffusion occurs. These vacancies are shown to interact with the excess interstitials introduced during dopant implantation to suppress TED.
C- and Z-shaped coordination compounds. synthesis, structure, and spectroelectrochemistry of cis- and trans-[Re(CO)3(L)]2-2,2'-bisbenzimidizolate with L = 4-phenylpyridine, 2,4'-bipyridine, or pyridine.

A series of C- and Z-shaped complexes of the form cis- and trans-[Re(CO)3(L)]2BiBzlm, where L = 4-phenylpyridine, 2,4'-bipyridine, or pyridine and BiBzlm = 2,2'-bisbenzimidizolate, have been synthesized by the reaction of[Re(CO) 4 ] 2 BiBzlm with a slight excess of L in refluxing tetrahydrofuran. Five of the six compounds have been isolated and crystallographically and electrochemically characterized. Formation of the sixth, the cis form of the [Re(CO)3(4-phenylpyridine)]2BiBzlm, is evidently inhibited by the torsional steric demands of proximal 4-phenylpyridines. The compounds are acyclic analogues of recently studied tetrarhenium molecular rectangles and are of interest, in part, because of their potential to form ligand-centered mixed-valence (LCMV) compounds upon reduction by one electron. Spectroelectrochemical measurements corroborated the formation of a LCMV version of cis-[Re(CO) 3 (L)] 2 BiBzlm but failed to uncover a ligand-based intervalence transition. Electrochemical measurements revealed isomer-dependent L/L electrostatic effects, resulting in greater mixed-valence ion comproportionation for C-shaped assemblies versus Z-shaped assemblies.
Perfringolysin O Association with Ordered Lipid Domains: Implications for Transmembrane Protein Raft Affinity

Upon interaction with cholesterol, perfringolysin O (PFO) inserts into membranes and forms a rigid transmembrane (TM) β-barrel. PFO is believed to interact with liquid ordered lipid domains (lipid rafts). Because the origin of TM protein affinity for rafts is poorly understood, we investigated PFO raft affinity in vesicles having coexisting ordered and disordered lipid domains. Fluorescence resonance energy transfer (FRET) from PFO Trp to domain-localized acceptors indicated that PFO generally has a raft affinity between that of LW peptide (low raft affinity) and cholera toxin B (high raft affinity) in vesicles containing ordered domains rich in brain sphingomyelin or distearoylphosphatidylcholine. FRET also showed that ceramide, which increases exposure of cholesterol to water and thus displaces it from rafts, does not displace PFO from ordered domains. This can be explained by shielding of PFO-bound cholesterol from water. Finally, FRET showed that PFO affinity for ordered domains was higher in its non-TM (prepore) form than in its TM form, demonstrating that the TM portion of PFO interacts unfavorably with rafts. Microscopy studies in giant unilamellar vesicles confirmed that PFO exhibits intermediate raft affinity, and showed that TM PFO (but not non-TM PFO) concentrated at the edges of liquid ordered domains. These studies suggest that a combination of binding to raft-associating molecules and having a rigid TM structure that is unable to pack well in a highly ordered lipid environment can control TM protein domain localization. To accommodate these constraints, raft-associated TM proteins in cells may tend to locate within liquid disordered shells encapsulated within ordered domains.
Fifty Years of Exchange Rate Research and Policy at the International Monetary Fund

This paper reviews the development over the past fifty years in the IMF of research on, and policy attitudes toward, exchange rate matters. Three successive phases are noted. In the first ten to fifteen years, within the confines of the par value system, research was mainly focused on achieving a better understanding of the working of exchange rates. From the early 1960s to the mid-1980s, the focus shifted toward discovering and, if possible, enforcing “correct” exchange rates. More recently, the limitations of that approach have led to increased attention to the merits of alternative exchange rate regimes, both among the industrial countries and for developing countries.
Sketching Sampled Data Streams

Sampling is used as a universal method to reduce the running time of computations -- the computation is performed on a much smaller sample and then the result is scaled to compensate for the difference in size. Sketches are a popular approximation method for data streams and they proved to be useful for estimating frequency moments and aggregates over joins. A possibility to further improve the time performance of sketches is to compute the sketch over a sample of the stream rather than the entire data stream.In this paper we analyze the behavior of the sketch estimator when computed over a sample of the stream, not the entire data stream, for the size of join and the self-join size problems. Our analysis is developed for a generic sampling process. We instantiate the results of the analysis for all three major types of sampling -- Bernoulli sampling which is used for load shedding, sampling with replacement which is used to generate i.i.d. samples from a distribution, and sampling without replacement which is used by online aggregation engines -- and compare these particular results with the results of the basic sketch estimator. Our experimental results show that the accuracy of the sketch computed over a small sample of the data is, in general, close to the accuracy of the sketch estimator computed over the entire data even when the sample size is only $10\%$ or less of the dataset size. This is equivalent to a speed-up factor of at least $10$ when updating the sketch.
Morphological artifacts induced in intracellularly stained neurons by dehydration: circumvention using rapid dimethyl sulfoxide clearing.

Abstract In order to observe the fine details of intracellularly stained neurons in brain slices the slices must be cleared of opaque matter. This clearing process involves dehydration of the slice, which typically results in significant shrinkage of the cleared tissue. However, how this shrinkage affects neuronal morphology has not been demonstrated to date. In this paper we detail the artifacts induced in the morphology of stained neurons by this clearing process. During dehydration-induced shrinkage of the brain slices, neurons stained with the water-soluble dye, Lucifer yellow, demonstrated a dramatic decrease in size to less than two-thirds of their original dimensions. In contrast neurons stained with the horseradish peroxidase/diaminobenzidine reaction-product did not shrink with the slice; instead the dendrites bent and curled during dehydration with no loss in cell-soma size. We have managed to circumvent these artifacts by using as a clearing agent the solvent dimethyl sulfoxide, which is miscible in both aqueous and organic phases. This solvent will clear tissue slices without inducing the concomitant artifacts caused by tissue shrinkage occurring with the alcohol-dehydration process.
Awareness is not enough: Commitment and performance implications of supply chain integration

Purpose – Given the tension between the rationale for and resistance to supply chain integration (SCI), the authors aim to provide an update on the rhetoric and reality of SCI and extend theory related to adoption and efficacy of integration strategies.Design/methodology/approach – The authors employ a multi‐method – survey and interview – replication approach to gauge the extent to which companies are increasing their engagement in SCI and assess integration's influence on firm performance.Findings – Despite managerial awareness of SCI's potential benefits, levels of integration have remained relatively unchanged over time. Integration is positively related to operational performance and firm performance – primarily through its influence on productivity and customer service. The interviews indicate some firms are beginning to manage value co‐creation initiatives across multiple tiers of the supply chain. They also reveal awareness of integration's competitive potential is insufficient to mobilize resourc...
AN ENTERPRISE DECISION MODEL FOR OPTIMAL VEHICLE DESIGN AND TECHNOLOGY VALUATION

Design optimization traditionally has dealt with engineering design decisions. Yet it is well understood that optimal product decisions must be based on engineering as well as marketing and production considerations. An enterprise decision model attempts to link these aspects of the product development enterprise so that the value of the designed product to the enterprise can be assessed. The model also values new product technology in accordance with the enterprise’s current operations to increase the likelihood of commercialization success before committing to a new strategy. The valuation technique uses comprehensive engineering simulation to provide a preliminary understanding of the technology’s market and design potential. The model represents the enterprise in a mathematical formulation that simultaneously optimizes initial product design, product pricing, operating costs associated with capacity allocation and design decisions, and the value created by new products. The article demonstrates such a model for optimal vehicle design in a medium truck market experiencing hybrid penetration.Copyright © 2003 by ASME
Loss of π-junction behavior in an interacting impurity Josephson junction

Using a generalization of the noncrossing approximation which incorporates Andreev reflection, we study the properties of an infinite-$U$ Anderson impurity coupled to two superconducting leads. In the regime where $\ensuremath{\Delta}$ and ${T}_{K}$ are comparable, we find that the position of the subgap resonance in the impurity spectral function develops a strong anomalous phase dependence---its energy is a minimum when the phase difference between the superconductors is equal to $\ensuremath{\pi}.$ Calculating the Josephson current through the impurity, we find that $\ensuremath{\pi}$-junction behavior is lost as the position of the bound state moves above the Fermi energy.
Phencyclidine-induced stereotyped behavior and serotonergic syndrome in rat

Abstract Phencyclidine (50 mg/kg, i.p.) induced in rats a biphasic response consisting of serotonergic syndrome followed by stereotyped behavior. The initial serotonergic syndrome was significantly reduced by cinanserin (20 mg/kg, i.p.) and cyproheptadine (2.0 mg/kg, i.p.) but not influenced by haloperidol (0.5 mg/kg, i.p.). The later stereotyped behavior was significantly reduced by haloperidol (0.5 mg/kg, i.p.) but not influenced by cinanserin (20 mg/kg, i.p.) or cyproheptadine (2.0 mg/kg, i.p.). A lower dose of phencyclidine (5.0 mg/kg, i.p.) elicited only haloperidol-sensitive stereotyped behavior. These results indicate that serotonergic and dopaminergic mechanisms may mediate the behavioral effects of phencyclidine in rats.
Epidural analgesia - Experience of 5628 patients in a large teaching hospital derived through audit

Abstract A prospective audit of 5628 surgical patients was conducted to determine the success, failure and complication rates associated with postoperative epidural analgesia. The majority of patients received infusions of bupivacaine 0.1% with hydromorphone 20 μg/cm3. However, elderly and frail patients received plain bupivacaine 0.1% or bupivacaine 0.1% with fentanyl 2 μg/cm3. Postoperatively, epidural infusions were selected, adjusted or terminated as indicated. Termination of epidural analgesia was defined as either success, if the infusion was continued until there was no further need for epidural analgesia, or failure, if the infusion was discontinued prematurely due to problems with the catheter or treatment that could not be controlled through intervention. Twenty-two percent of patients had their epidural catheter removed prematurely due to either technical (catheter) or treatment (medication) problems that could not be resolved. Technical problems with the catheter caused 807 failures (14% of all patients). Almost 70% of the technical failures (N=554) were due to catheter dislodgement. Treatment problems resulted in 451 failures (8% of all patients). The majority of treatment failures were due to inadequate analgesia despite functioning catheters. This audit has proved useful in maintaining standards of care and in identifying problems with postoperative epidural therapy that still need improvement. It allows a balanced assessment of the value of this treatment in the setting of a large teaching hospital and is the largest reported series of postoperative epidural hydromorphone analgesia.
Does Head Rotation Contribute to Gaze Stability during Passive Translations

Active translations of human subjects are nearly perfectly compensated by a combined rotation of both the eyes and the head. Because vestibuloocular reflex (VOR) gain is less than perfect during pa...
Reasons for dropout from drug abuse treatment : Symptoms, personality, and motivation

Previous research has identified risk factors for early attrition from substance abuse treatment, but has not assessed reasons for dropout from the client's perspective. Interview and self-report assessment data were collected from 24 clients who prematurely terminated outpatient treatment to evaluate their subjective reasons for dropping out and the association of these reasons with demographic and clinical variables. Items from scales indicating problems with client motivation or conflicts with program staff were the most commonly endorsed. The severity of participant's symptoms and logistical problems interfering with appointments were less commonly reported as reasons for dropping out. Demographic, substance abuse, and motivational stage indicators were infrequently associated with subjective reasons for dropout. In contrast, indicators of maladaptive personality functioning were strongly associated with many reasons for dropping out, especially concerns about privacy and boundary issues within the program. Results from this preliminary evaluation will guide the development of an instrument and intervention focused on dropout risk factors and treatment reengagement.