cssi/SciSciGPT-SciSciNet huggingface dataset:
V1647 ORIONIS: KECK/NIRSPEC 2 μm ECHELLE OBSERVATIONS

We present new Keck II NIRSPEC high-spectral resolution 2 μm echelle observations of the young eruptive variable star V1647 Orionis. This star went into outburst in late 2003 and faded to its pre-outburst brightness after approximately 26 months. V1647 Orionis is the illuminating star of McNeil's Nebula and is located near M 78 in the Lynds 1630 dark cloud. Our spectra have a resolving power of approximately 18,000 and allow us to study in detail the weak absorption features present on the strong near-IR veiled continuum. An analysis of the echelle orders containing Mg I (2.1066 μm) and Al I (2.1099 μm), Brγ (2.1661 μm), the Na I doublet (2.206 and 2.209 μm), and the CO overtone bandhead (2.2935 μm) gives us considerable information on the physical and geometric characteristics of the regions producing these spectral features. We find that, at high spectral resolution, V1647 Orionis in quiescence resembles a significant number of FU Orionis type eruptive variables and does not appear similar to the quiescent EX Lupi variables observed. This correspondence is discussed and implications for the evolutionary state of the star are considered.
Network-oriented simulation of variable reluctance motor drive systems with PWM control

Mixed-technology systems defined as networks of interconnected components may be simulated by imposing conservation of flow at each node. Given a library of physical component models in a standard form and the means to embed software algorithms for control, this approach to simulation requires little more from the user than to specify what types of physical components are present and how these physical components are interconnected to each other and to the control algorithms. This paper summarizes the technical foundations for this user-friendly simulation philosophy and reports in some detail its application to variable reluctance motor drive systems. Novel features include the development of both switched and averaged models of the pulse-width modulated inverter, and the design and demonstration of high-performance position control algorithms.
Whole Body MRI: Local and Inserted Gradient Coils

The sections in this article are 1 Introduction 2 Safety 3 Design Considerations 4 Design Techniques 5 Example Coil Designs 6 Applications 7 Summary 8 Biographical Sketch Related Articles
Cholesterol--Making or Breaking the Synapse

Synapses are regions where neurons meet and communicate. But how is their formation regulated in the developing and adult brain? As [Smith and Barres][1] explain in their Perspective, the answer could not be simpler. It turns out that, at least in the culture dish, a type of glial cell called an astrocyte produces the molecule cholesterol, which is taken up by neurons and then directs formation of synapses perhaps by regulating vital signaling pathways ([ Mauch et al .][2]). [1]: http://www.sciencemag.org/cgi/content/full/294/5545/1296 [2]: http://www.sciencemag.org/cgi/content/short/294/5545/1354
Photo-Cybernetics: Fiber Optics Use in Motor Vehicle Electronic Controls and Monitors

The paper shows simplified wiring diagrams for an electro- optical multiplexing control system and describes how such a system can be fabricated, installed, and repaired. In addition, examples of fiber optics monitoring systems are illustrated and explained. /GMRL/
Effective Home-School- Community Relations for Secondary School Improvement

(1986). Effective Home-School-Community Relations for Secondary School Improvement. The Clearing House: A Journal of Educational Strategies, Issues and Ideas: Vol. 59, No. 7, pp. 312-315.
Identification of T-cell epitopes in Francisella tularensis using an ordered protein array of serological targets.

Francisella tularensis is a Gram-negative intracellular bacterium that is the causative agent of tularaemia. Concerns regarding its use as a bioterrorism agent have led to a renewed interest in the biology of infection, host response and pathogenesis. A robust T-cell response is critical to confer protection against F. tularensis. However, characterization of the cellular immune response has been hindered by the paucity of tools to examine the anti-Francisella immune response at the molecular level. We set out to combine recent advances of genomics with solid-phase antigen delivery coupled with a T-cell functional assay to identify T-cell epitopes. A subset of clones, encoding serological targets, was selected from an F. tularensis SchuS4 ordered genomic library and subcloned into a bacterial expression vector to test the feasibility of this approach. Proteins were expressed and purified individually employing the BioRobot 3000 in a semi-automated purification method. The purified proteins were coupled to beads, delivered to antigen-presenting cells for processing, and screened with Francisella-specific T-cell hybridomas of unknown specificity. We identified cellular reactivity against the pathogenicity protein IglB, and the chaperone proteins GroEL and DnaK. Further analyses using genetic deletions and synthetic peptides were performed to identify the minimal peptide epitopes. Priming with the peptide epitopes before infection with F. tularensis LVS increased the frequency of antigen-specific CD4 T cells as assessed by intracellular interferon-γ staining. These results illustrate the feasibility of screening an arrayed protein library that should be applicable to a variety of pathogens.
Learning about Stress through Interviews

(2001). Learning about Stress through Interviews. American Journal of Health Education: Vol. 32, Special Issue on Mental Health, pp. 313-314.
A Note on the Asymptotic Distribution of Berk—Jones Type Statistics under the Null Hypothesis

Proofs are given of the limiting null distributions of the statistics of Berk and Jones (1979) and of Einmahl and McKeague (2002).
Autoantibodies against 3‐hydroxy‐3‐methylglutaryl‐coenzyme A reductase in patients with statin‐associated autoimmune myopathy

Statins lower cholesterol levels by specifically inhibiting HMGCR, a key enzyme in the cholesterol biosynthetic pathway. These drugs significantly reduce cardiovascular endpoints and are among the most commonly prescribed medications, with almost 30 million people in the U.S. prescribed a statin in 2005 (1). Musculoskeletal symptoms are a well-known complication of statin use and range from myalgias and cramps, which occur in 9–20% of statin users (2–4) to life-threatening rhabdomyolysis, a rare event occurring at a rate of ~0.4 per 10,000 patient years (5). In most cases, statin-induced myopathic events are self-limited, with complete recovery in the weeks or months after the statin is discontinued (6). However, two recent studies have described 33 patients who developed an autoimmune myopathy following statin exposure, which did not abate after discontinuing statins (7, 8). Taking a different approach, we recently identified sixteen patients with a necrotizing myopathy who had a novel autoantibody recognizing ~200 and ~100 kDa proteins (9). Given that these patients had proximal muscle weakness, elevated CK levels, MHC I expression on non-necrotic muscle fibers, autoantibodies, and responded to immunosuppression, we concluded that these patients had an IMNM. Of the 12 anti-200/100 positive patients over the age of 50, 10 had prior statin exposure (83%). This was significantly higher than the frequency of statin exposure in age-matched controls with polymyositis (PM), dermatomyositis (DM), and inclusion body myositis (IBM). We reasoned that statin-associated autoimmune myopathy with anti-200/100 autoantibodies provides a model system for defining the mechanistic relationship between drug exposure and developing a specific autoimmune response. Identification of the autoantigen(s) targeted by the immune response is a critical first step. In this study, we demonstrated that statin exposure upregulates expression of the ~200 and ~100 kDa autoantigens. Given that statin exposure also increases expression of the ~97 kDa HMGCR (10, 11), we investigated whether this enzyme might be the ~100 kDa autoantigen. Serum from anti-200/100 positive patients specifically recognized the intracellular catalytic domain of HMGCR. Based on this finding, we developed an ELISA assay to rapidly screen patient sera for anti-HMGCR autoantibodies. We found that 45 of 750 patients with symptoms of muscle disease were anti-HMGCR positive (6%). Anti-HMGCR positive patients had an IMNM phenotype and greater than 90% of those over age 50 had prior statin exposure. Interestingly, HMGCR expression was upregulated in regenerating muscle fibers from anti-HMGCR positive patients. These studies suggest that statins trigger an autoimmune response against HMGCR by upregulating expression of this autoantigen. Even after discontinuing statins, the presence of high levels of HMGCR in regenerating muscle fibers may perpetuate the immune response.
Synchronization of ovulation in dairy cows using PGF2α and GnRH

This paper reports a new method for synchronizing the time of ovulation in cattle using GnRH and PGF(2alpha). In Experiments 1 and 2, lactating dairy cows (n=20) ranging from 36 to 280 d postpartum and dairy heifers (n=24) 14 to 16 mo old were treated with an intramuscular injection of 100 mug GnRH at a random stage of the estrous cycle. Seven d later the cattle received PGF(2alpha) to regress corpora lutea (CL). Lactating cows and heifers received a second injection of 100 mug GnRH 48 and 24 h later, respectively. Lactating cows were artificially inseminated 24 h after the second GnRH injection. Ovarian morphology was monitored daily by trans-rectal ultrasonography from 5 d prior to treatment until ovulation. In Experiment 3, the flexibility in the timing of hormonal injections with this synchronization protocol was evaluated by randomly assigning 66 lactating dairy cows to 3 different treatment groups. Lactating cows received the injection of PGF(2alpha) 48 (Group 1), 24 (Group 2), and 0 h (Group 3) prior to the second injection of GnRH, which was administered at the same time in each group to ensure the second injection of GnRH was given when follicles were at a similar stage of growth. In Experiments 1 and 2, the first injection of GnRH caused ovulation and formation of a new or accessory CL in 18 20 cows and 13 24 heifers. In addition, this injection of GnRH initiated or was coincident with initiation of a new follicular wave in 20 20 lactating cows and 18 24 heifers. Corpora lutea regressed after PGF(2alpha) in 20 20 cows and in 18 24 heifers. All cows and 18 24 heifers ovulated a newly formed dominant follicle between 24 and 32 h after the second injection of GnRH. Ten of 20 cows conceived to the timed artificial insemination. In Experiment 3, the conception rate in Groups 1 and 2 were greater than in Group 3, (55 and 46 % vs 11%, respectively). In summary, this protocol could have a major impact on managing reproduction in lactating dairy cows, because it allows for AI to occur at a known time of ovulation and eliminates the need for detection of estrus.
Geometry Optimization of a Flow-Based Device to Maximize Selectin-Mediated Hematopoietic Stem Cell Enrichment

Rare cell enrichment techniques must selectively capture and successfully retain cells that exist at < 5% in a suspension. We developed a device to capture hematopoietic stem and progenitor cells (HSPCs) from adult bone marrow using immobilized adhesion molecules called selectins in the presence of a flow field. While we continue to optimize the immobilized protein surface and improve the selectivity of the device for HSPCs, it appears to be at the expense of cell recovery. To address this issue, we used experimental and computational methods to identify the hydrodynamic factors that contribute to cell capture, and present new designs for the device that could improve HSPC recovery without affecting the selectivity. We tested KG1a cell recovery using four configurations of tubing — straight cylindrical, helical, flattened and axially pinched, and two cell loading conditions: static and continuous oscillatory. We utilized COMSOL 3.4 finite element modeling software to investigate the path of particles introduced into these geometries, the fluid velocities and local wall shear stresses, and the predicted recovery efficiency based on the number of particles that contact and stick to the walls of the geometries. We found that, experimentally, the highest number of cells were recovered using static cell loading in a straight cylindrical tubing, but we predict that a corrugated or pinched geometry could further increase recovery under desirable flow conditions.Copyright © 2008 by ASME
Role of active site water molecules and substrate hydroxyl groups in oxygen activation by cytochrome P450 158A2: a new mechanism of proton transfer.

From the x-ray crystal structure of CYP158A2 (Zhao, B., Guengerich, F. P., Bellamine, A., Lamb, D. C., Izumikawa, M., Lei, L., Podust, L. M., Sundaramoorthy, M., Reddy, L. M., Kelly, S. L., Kalaitzis, J. A., Stec, D., Voehler, M., Falck, J. R., Moore, B. S., Shimada, T., and Waterman, M. R. (2005) J. Biol. Chem. 280, 11599-11607), one of 18 cytochrome P450 (CYP) genes in the actinomycete Streptomyces coelicolor, ordered active site water molecules (WAT505, WAT600, and WAT640), and hydroxyl groups of the substrate flaviolin were proposed to participate in proton transfer and oxygen cleavage in this monooxygenase. To probe their roles in catalysis, we have studied the crystal structures of a substrate analogue (2-hydroxy-1,4-naphthoquinone) complex with ferric CYP158A2 (2.15 A) and the flaviolin ferrous dioxygen-bound CYP158A2 complex (1.8 A). Catalytic activity toward 2-hydroxy-1,4-naphthoquinone was ∼70-fold less than with flaviolin. In the ferrous dioxygen-bound flaviolin complex, the three water molecules in the ferric flaviolin complex still occupy the same positions and form hydrogen bonds to the distal dioxygen atom. These findings suggest that CYP158A2 utilizes substrate hydroxyl groups to stabilize active site water and further assist in the iron-linked dioxygen activation. A continuous hydrogen-bonded water network connecting the active site to the protein surface (bulk solvent) not present in the other two ferrous dioxygen-bound P450 structures (CYP101A1/P450cam and CYP107A1/P450eryF) is proposed to participate in the proton-delivery cascade, leading to dioxygen bond scission. This ferrous-dioxygen structure suggests two classes of P450s based on the pathway of proton transfer, one using the highly conserved threonine in the I-helix (CYP101A1) and the other requiring hydroxyl groups of the substrate molecules either directly transferring protons (CYP107A1) or stabilizing a water pathway for proton transfer (CYP158A2).
A provisional, annotated, list of the nominal taxa assigned to the genus Dasypoda Latreille, 1802, with the description of an additional species (Hymenoptera, Apoidea, Melittidae)

A provisional, annotated, list of the nominal species assigned to the Old-World (Palaearctic) genus Dasypoda Latreille, 1802, is given. Lectotypes are designated for Dasypoda panzeri Spinola, 1839, D. albipila Spinola, 1839, and D. comberi Cockerell, 1911. Dasypoda litigator sp. nov., is described from Iran.
Signal Decay through a Reverse Phosphorelay in the Arc Two-component Signal Transduction System

Escherichia coli senses and signals anoxic or low redox conditions in its growth environment by the Arc two-component system. Under those conditions, the tripartite sensor kinase ArcB undergoes autophosphorylation at the expense of ATP and subsequently transphosphorylates its cognate response regulator ArcA through a His → Asp → His → Asp phosphorelay pathway. In this study we used various combinations of wild-type and mutant ArcB domains to analyze in vitro the pathway for signal decay. The results indicate that ArcA-P dephosphorylation does not occur by direct hydrolysis but by transfer of the phosphoryl group to the secondary transmitter and subsequently to the receiver domain of ArcB. This reverse phosphorelay involves both the conserved His-717 of the secondary transmitter domain and the conserved Asp-576 of the receiver domain of ArcB but not the conserved His-292 of its primary transmitter domain. This novel pathway for signal decay may generally apply to signal transduction systems with tripartite sensor kinases.
Initial effects of deforestation on physical characteristics of a boreal river

Physical characteristics of the Piscataquis River, a fourth-order river in Maine, USA, were studied for one year prior to and one year following clearcut deforestation of the spruce-fir watershed. Results suggest that even the most careful, and apparently innocuous, timber harvest operation may alter the physical character of a river system. Significant changes in several factors, including thermal regime, benthic organic matter, substrate composition and suspended particulate matter were observed after logging. Changes were largely consistent with results of studies of smaller streams in deciduous forests, and with predictions of the River Continuum Concept. Post-logging conditions should favor a shift from heterotrophy to autotrophy in the trophic structure of the river community.
Radial head fractures: loss of cortical contact is associated with concomitant fracture or dislocation

Hypothesis Among radial head fractures displaced greater than 2 mm (Broberg and Morrey modified Mason type 2), separation (complete loss of cortical contact) of at least 1 radial head fracture fragment is associated with a complex injury pattern, meaning that there are other concomitant elbow fractures or ligament injuries. Materials and methods We identified 291 consecutive skeletally mature patients with 296 radial head fractures treated during a 6-year period. Of these, 121 consecutive fractures of part of the radial head displaced greater than 2 mm (type 2) were classified according to whether there was complete lack of cortical contact between a fracture fragment and the rest of the proximal radius. Predictors of isolated vs complex injury pattern were sought in bivariate and multivariable analyses. Results Of 121 fractures, 30 (25%) were classified as having cortical contact, and 91 (75%) were classified as not having cortical contact. Ten (33%) with cortical contact were part of a complex elbow injury, and 83 of 91 fractures (91%) without cortical contact were part of a complex elbow injury ( P Conclusions Among Mason type 2 fractures, complete loss of cortical contact of at least one fracture fragment is strongly predictive of a complex injury pattern. Level of evidence 4, Retrospective case series, Treatment study
Simultaneous effects of food limitation and inducible resistance on herbivore population dynamics

Many herbivore populations fluctuate temporally, but the causes of those fluctuations remain unclear. Plant inducible resistance can theoretically cause herbivore population fluctuations, because herbivory may induce plant changes that reduce the survival or reproduction of later-feeding herbivores. Herbivory can also simply reduce the quantity of food available for later feeders and this, too, can cause population fluctuations. Inducible resistance and food limitation often occur simultaneously, yet whether they jointly facilitate or suppress herbivore fluctuations remains largely unexplored. We present models that suggest that food limitation and inducible resistance may have synergistic effects on herbivore population dynamics. The population-level response of the food plant to herbivory and the details of how inducible resistance affects herbivore performance both influence the resulting herbivore dynamics. Our results identify some biological properties of plant-herbivore systems that might determine whether or not cycles occur, and suggest that future empirical and theoretical population dynamics studies should account for the effects of both food limitation and inducible resistance.
Affinity tests for the detection of community alteration in plankton: Evaluation with a distributional computer model

Abstract A general method is outlined for the evaluation of sampling and data reduction procedures of the sort often used in environmental monitoring projects. Using the example of marine macrophytoplankton under stress from a thermal effluent, a spatial distribution model of species within the phytoplankton community is constructed by computer. Stochastic temporal variation of the community is built into the model. Samples can then be generated and analysed by different data reduction techniques at low cost. The efficiency of the analytical tests can be evaluated by noting the degree to which they uncover the known characteristics of the artificial community. The usefulness of affinity testing in this sort of study is discussed, and two procedures (Fager's recurrent group analysis and Orloci's n-dimensional clustering) are evaluated using the phytoplankton model. The Fager procedure is found to be superior in a sampling scheme that is likely to be employed in actual field studies.
Accumulation of collagen in skeletal muscle, heart and liver of the chick embryo

Abstract 1. 1. The collagen content was determined in the leg musculature, the heart ventricles, and the liver of chick embryos from the 10th day of incubation to the 21st day after hatching. 2. 2. Previous to the 19th day of development, the constants for the rate of collagen accumulation in leg muscle was found to be highest (0.69), slower in the heart (0.48), and slowest in the liver (0.45). Following the 19th day the constants were found to be 0.079, 0.090, and 0.23 for leg muscle, heart, and liver, respectively. 3. 3. During limited periods of development, the NaOH-extracted tissues were found to give significantly lower collagen values than tissues extracted with urea.
Managing risk in agriculture through hedging and crop insurance: what does a national survey reveal?

Crop insurance and hedging are two risk management strategies used by farmers to manage risk. Using a discrete choice model and farm‐level data, this study investigates the factors influencing farmers’ use of hedging and crop insurance as risk management strategies. In the case of crop insurance, results indicate that level of education, participation in other risk management strategies (such as renting land, commodity programs, spreading sales over the year), and controlling debt are positively related to a farmer’s decision to purchase crop insurance. For the hedging model, results suggest education, off‐farm income, forward contracting sales of crops and livestock, and computer use are positively related to a farmer’s articipation in hedging/futures markets.
Retinoic Acid Inhibition of Cell Cycle Progression in MCF-7 Human Breast Cancer Cells

Cell cycle analysis indicates that retinoic acid (RA) inhibition of MCF-7 cell growth occurs through induction of G1 arrest with a concomitant reduction in the proportion of cells in S and G2 + M phases. RA did not affect cyclins D1, A, and E and cyclin-dependent kinase 2 (CDK2) expression, but significantly reduced cyclin D3 and CDK4 expression after 24 h. RA also inhibited cyclin B1 and CDC2 expression, possibly responsible for the reduction of the proportion of cells in G2 + M and S phases. RA did not induce p16 and p27 expression, but obviously reduced p21 level in MCF-7 cells. The retinoid markedly reduced pRB protein level and abrogated pRB phosphorylation after 48 h; it also reduced transcription factor E2F1 expression at both the mRNA and protein levels. E2F1 promoter activity was reduced by 60%, which is probably responsible, at least in part, for the reduction of E2F1 expression in RA-treated MCF-7 cells. These observations demonstrate a marked effect of RA on some of the key cell cycle regulatory proteins in MCF-7 cells. Cyclin D3 and CDK4 are likely the early targets of RA, followed by reduced pRB expression and phosphorylation, as well as by the inhibition of the E2F1 transcription factor which controls progression from G1 to S phase. Most of these events precede the observed reduction in MCF-7 cell growth, which begins at Day 3 of RA treatment.
STRUCTURE OF THE HUMAN WART VIRUS.

The several fractions of the human wart virus from the bands obtained by sucrose density gradient centrifugation have been studied electron microscopically by the negative contrast technique. The uppermost band consisted of amorphous debris and occasional phosphotungstate-penetrated particles. The next lower, very thin band was composed almost entirely of particles penetrated by the phosphotungstate and probably devoid of internal material. Band 3 consisted of intact particles of well-preserved structure. The hollow, tubular capsomeres that studded the surface of the particles in this band measured about 80 A in diameter and projected outward about 50–60 A. Bands 3 and 4 contained some bizarre elongated, enlarged, and dumbbell forms whose surface was composed of capsomeres typical of those covering the particulate form of the wart virus. Two types of particulate forms were demonstrated in preparations obtained by mercury spreading.
Hematuria and massive calycovenous reflux secondary to benign renal cyst

Abstract A case is reported in which massive calycovenous reflux adjacent to an upper pole mass was demonstrated on a retrograde pyelogram. Pathologic examination revealed that the underlying lesion was a simple cyst.
Imputing Values for Directly- Or Contractually-Transferred Feeder Pigs

The feeder pig industry is a significant part of the U.S. hog industry. A decade ago, roughly one-fourth of all market hogs slaughtered in the United States were bought as feeder pigs (Van Arsdall and Nelson). More recently, the hog industry has become increasingly industrialized with contract hog production becoming more prevalent, yet the feeder pig industry does not seem to have diminished in importance as specialization in feeder pig production is still common (Rhodes 1990, 1995). The pricing of feeder pigs takes place under a variety of market mechanisms. Roughly one-third are sold in traditional public auctions while another 8 percent are sold in electronic feeder pig auctions (Van Arsdall and Nelson). The remaining sales take place via direct transfer from pig producers to finishers with much of this direct transfer done under contract.
A Two Zone Turbulent Flow Reactor Facility for Studies of Staged Combustion of Simulated Hazardous Wastes

Abstract A two zone turbulent flow laboratory reactor has been constructed and validated for use in staged combustion studies. A premixed fuel/air feed enters the toroidal backmixed primary zone. The effluent mixes with additional injected oxidant and/or steam, and then enters the linear flow secondary zone. This sequence emulates many large scale combustors. Extracted gas samples from cooled probes located in each zone are subjected to several dedicated on-line gas analyzers, and separation/analyses by on-line/batch gas chromatography. Modeling of the combustor is performed with detailed reaction mechanisms and an idealized perfectly stirred reactor + plug flow reactor sequence. The experimental feed rates and measured temperatures are input to the model. Staged combustion for NO minimization has been demonstrated for an ethylene/monomethyl amine feed
Synthesis and Characterization of (Me3ECH2)2Ta(CHEMe3)Si(SiMe3)3 (E = C, Si). Kinetic and Mechanistic Studies of the Formation of a Silyl Alkylidene Complex through Preferential Silane Elimination

Silyl alkylidene complexes (Me3ECH2)2Ta(CHEMe3)Si(SiMe3)3 (E = C, 1; E = Si, 2), which are free of anionic π-ligands such as cyclopentadienyl (Cp), were prepared through the reactions of (Me3ECH2)3TaCl2 with 2 equiv of LiSi(SiMe3)3(THF)3. An unprecedented preferential elimination of silane HSi(SiMe3)3 leads to the formation of the alkylidene bonds in 1 and 2. An intermediate (Me3SiCH2)3Ta(Cl)Si(SiMe3)3 (9) was observed in the formation of 2. 9 was found to react with LiSi(SiMe3)3(THF)3 and LiCH2SiMe3 to form 2 and (Me3SiCH2)3TaCHSiMe3 (6), respectively. The reaction of 9 with LiSi(SiMe3)3(THF)3 to form the silyl alkylidene complex 2 follows a pathway different from the reaction of (Me3ECH2)4TaCl (E = C, Si) with LiCH2EMe3 to form alkyl alkylidene complexes (Me3ECH2)2TaCHEMe3. The decomposition of 9 was found to follow first-order kinetics, with ΔH⧧ = 17.2(1.0) kcal/mol and ΔS⧧ = −4(4) eu, and give an unstable dimeric alkylidene complex (Me3SiCH2)4(Cl)2Ta(CHSiMe3)2 (12). The reaction between 9 and LiSi(SiM...
Genetic Instability and the Etiology of Somatic PIG-A Mutations in Paroxysmal Nocturnal Hemoglobinuria

Abstract ABSTRACT: Paroxysmal nocturnal hemoglobinuria (PNH) is a hematologic disorder characterized by acquired PIG-A gene mutations that lead to defective bioassembly of glycosylphosphatidylinositol (GPI) anchors and the absence of GPI-linked surface proteins. As the etiology of these acquired PIG-A gene mutations is unknown, we hypothesized that patients with PNH have overall genetic instability and acquire somatic mutations throughout their genome. We first analyzed microsatellite sequences and found equivalent size variation using DNA from GPI-negative granulocytes compared with the DNA of paired GPI-positive B cell lines or normal granulocytes. We next quantitated the frequency of mutations at the hypoxanthine-guanine phosphoribosyl transferase ( hprt ) gene locus, and found 1 PNH patient with a large increase in hprt - mutant frequency (256.7 x 10 -6 vs. 27.8 ± 19.9 x 10 -6 for normal adults) that was confirmed on 4 independent blood samples. We also quantitated “illegitimate” VDJ genetic recombination events between the T cell receptor Vγ and J β gene loci, and found a second PNH patient with a large increase (43.5 events per μg of DNA vs. 1.3 ± 0.8 events per μg of DNA for normal adults), confirmed on 4 independent DNA samples. Both of these PNH patients are young females with no history of aplastic anemia. Our data show that PNH patients can have increased numbers of acquired somatic mutations in gene loci distinct from PIG-A. These data suggest that genetic instability may be associated with the development of PIG-A mutations that lead to the clinical picture of PNH.
Damping characteristics of composite materials and structures

This paper presents an overview of experimental and analytical approaches that have been used to characterize damping properties of composite materials and structures, with emphasis on polymer composites. A discussion of damping mechanisms operating in composites is followed by a review of several experimental methods for measuring damping. A summary of analytical models for predicting damping at both the micromechanical and macromechanical levels is presented and comments on ways of improving and optimizing damping in composites are offered.
Knowledge base refinement as improving an incorrect and incomplete domain theory

Abstract : The ODYSSEUS program automates knowledge base refinement by improving a domain theory. This paper describes the techniques used by ODYSSEUS to address three types of domain theory pathologies: incorrectness, inconsistency, and incompleteness. In ODYSSEUS, an incomplete domain theory is extended by the Metarule Chain Completion Method. This method exploits the use of an explicit meta-level representation of the strategy knowledge for a generic problem class (e.g., heuristic classification) that is separate from the domain theory (e.g., medicine) to be improved. Our work implements and compares the extension of an incompleted domain theory using case-based inductive learning and explanation- based apprenticeship learning; in the latter, learning occurs by completing failed explanations of observed human problem-solving actions. Extending an incomplete domain theory and correcting an incorrect domain theory both use the Confirmation Decision Procedure Method, which validates arbitrary instantiated tuples of the knowledge base by the use of an underlying domain theory. Lastly, the consistency of the knowledge base is improved by use of the Sociopathic Reduction Algorithm. (kr)
Toxic responses to defined chemical mixtures: Mathematical models and experimental designs

Abstract The problem and relevance of assessing biological responses to chemical mixtures is presented with reference to the literature on this problem and its possible solutions. This review is intended for a general audience as an introduction to, and comment on, assessing the interactions of defined mixtures of xenobiotics. The focus is on experimental toxicology, however, the methods are also applicable to pharmacology. Much of the literature on this topic is quite specialized in statistics, theory, or specific applications. This may deter a significant portion of the growing number of investigators in this field from using this literature, and may partially account for the persistent use of methods which have been shown to permit precarious conclusions. References are given for some of the most comprehensive and recent work and reviews on the subject. The reader is given some familiarity with this topic's basic problems and ideas, and the controversy on terminology. One example is presented of a popular experimental design and data analysis method which while applicable in some situations, has been shown to lead to precarious and even erroneous conclusions. Eight other methods of data analysis are briefly presented and some of their advantages, disadvantages, assumptions, and limitations are discussed. These methods were selected to illustrate similarities and differences in the various approaches taken in addressing this problem. Three basic types of experimental design appropriate to these kinds of studies are outlined. General considerations, suggested guidelines, and possible pitfalls in experimental design, and data analysis of biological responses to chemical mixtures are discussed.
Chemical reactions simulated by ground-water-quality models

: Recent literature concerning the modeling of chemical reactions during transport in ground water is examined with emphasis on sorption reactions. The theory of transport and reactions in porous media has been well documented. Numerous equations have been developed from this theory, to provide both continuous and sequential or multistep models, with the water phase considered for both mobile and immobile phases. Chemical reactions can be either equilibrium or non-equilibrium, and can be quantified in linear or non-linear mathematical forms. Non-equilibrium reactions can be separated into kinetic and diffusional rate-limiting mechanisms. Solutions to the equations are available by either analytical expressions or numerical techniques. Saturated and unsaturated batch, column, and field studies are discussed with one-dimensional, laboratory-column experiments predominating. A summary t able is presented that references the various kinds of models studied and their applications in predicting chemical concentrations in ground waters.
Local automorphism invariance: Gauge boson mass without a Higgs particle

The consequences of the assumption of invariance of a spinor theory under local automorphism transformations of the Clifford algebra basis elements are explored. This invariance is equivalent to allowing the orthonormal basis spinors of the spinor space to be chosen arbitrarily at each point in space–time and is analogous to the situation in general relativity where the orthonormal basis vectors of the tangent space are allowed to be chosen arbitrarily at each point in space–time. This invariance then dictates that the Clifford algebra generators be functions of space–time and is implemented by introducing new fields, the drehbeins (‘‘spin legs’’), which are somewhat akin to the vielbeins introduced in general relativity to invoke the concept of local Lorentz invariance. However, in contrast to general relativity, the covariant derivatives of the Clifford algebra generators do not vanish. The dynamical variables of the theory are then the spinors, the gauge fields of the automorphism group, and the drehbeins. The invariant Lagrangian density and the concomitant field equations for this theory are discussed. Interestingly, the ‘‘kinetic’’ Lagrangian density term for the drehbein fields induces a gauge invariant mass term for the gauge fields. This constitutes a new mass generation mechanism, of different character and complementary to the familiar Higgs mechanism. Although the idea of local automorphism invariance is a natural generalization of the principle of equivalence, herein attention is restricted to the case of nondynamic flat space–time.
Environmental Justice 2.0: new Latino environmentalism in Los Angeles

This paper presents the results of ethnographic research conducted with several environmental justice (EJ) organisations in Latino communities of Los Angeles, California. Traditional EJ politics revolves around research and advocacy to reduce discriminatory environmental exposures, risks, and impacts. However, I argue that in recent years there has been a qualitative change in EJ politics, characterised by four main elements: (1) a move away from the reaction to urban environmental “bads” (e.g. polluting industries) in the city towards a focus on the production of nature in the city; (2) strategies that are less dependent on the legal, bureaucratic, and technical “regulatory route”; (3) the formation of a distinctive “Latino environmental ethic” that offers a more complex consideration of the place of race in EJ organising; and (4) a spatial organisation of EJ politics that moves away from hyperlocal, vertical organisation towards diversified city-wide networks that include EJ organisations, mainstream en...
Eye and Head Movements in Peripheral Vision: Nature of Compensatory Eye Movements

Simultaneous recordings of both eye and head movements in response to a peripheral signal indicated that the backward compensatory eye movement was initiated during the constant velocity of the head rotation. This compensatory movement began before the eyes had actually reached the peripheral signal.
Diagnostic, treatment and aftercare approaches to cocaine abuse

Abstract The general public feels that cocaine is not particularly dangerous because it does not produce a well defined physical dependency and abstinence syndrome. However, when addiction is defined as compulsion, loss of control and continued use in spite of adverse consequences, cocaine drug hunger can be seen as an agent of addictive disease. Withdrawal from cocaine dependence usually involves depression, anxiety and lethargy. These usually clear within a week, leaving only the “drug hunger” to contend with. Medication is rarely needed. When cocaine is the primary addiction, after withdrawal the most effective treatment is group therapy with other recovering cocaine abusers. We incorporate the principles of recovery and define positive and constructive alternatives in dealing with cocaine hunger. Recovery programs should be flexible and involve individual and family education on recovery and the nature of addictive disease. Exercise that produces cardiopulmonary stimulation is a helpful means of reducing drug hunger and anxiety during recovery therapy.
Glycemic control, reported pain and leakage with a 4 mm × 32 G pen needle in obese and non-obese adults with diabetes: a post hoc analysis

AbstractObjective:The shortest pen needle (PN) for subcutaneous insulin therapy is 4 mm. Clinicians may hesitate to use it in obese patients. We report a post hoc analysis of a previously published study of the 4 mm × 32 G PN, evaluating responses in obese (≥30 kg/m2) and non-obese (<30 kg/m2).Methods:Subjects (BMI 20 to 49 kg/m2, 52% obese) with diabetes used 4 mm × 32 G PNs and either 5 mm or 8 mm PNs (both 31 G) in two, 3-week treatment periods in a randomized noninferiority cross-over trial. Percentage absolute change in fructosamine (%│Δ Fru│) was the primary endpoint. Equivalent glycemic control was defined as %│Δ Fru│ within 20% (including 95% CI). The impact of obesity on change in fructosamine, pain and reported insulin leakage from the skin is described.Clinical trial registration:Clinicaltrials.gov – identifier: NCT00928057.Limitations:This report is a post hoc analysis of two BMI subgroups resulting in smaller sample sizes.Results:Of 168 who completed the study, 163 were included in the fructo...
THE CDF SVX-II UPGRADE FOR THE TEVATRON RUN II

A microstrip silicon detector SVX II has been proposed for the upgrade of CDF to be installed in 1999 for Run II of the Tevatron. Three barrels of five layers of double-sided silicon microstrip detectors will cover the interaction region. A description of the project status will be presented. Emphasis will be given to the R&D program for silicon sensors which includes capacitance minimization, the study of coupling capacitor integrity, the operation of the detectors in conjunction with the SVXH and SVX2 readout chips in two beam tests and the determination of the detectors performance deterioration due to radiation damage.
Plasmon-enhanced water splitting on TiO2-passivated GaP photocatalysts

Integrating plasmon resonant nanostructures with photocatalytic semiconductors shows great promise for high efficiency photocatalytic water splitting. However, the electrochemical instability of most III–V semiconductors severely limits their applicability in photocatalysis. In this work, we passivate p-type GaP with a thin layer of n-type TiO2 using atomic layer deposition. The TiO2 passivation layer prevents corrosion of the GaP, as evidenced by atomic force microscopy and photoelectrochemical measurements. In addition, the TiO2 passivation layer provides an enhancement in photoconversion efficiency through the formation of a charge separating pn-region. Plasmonic Au nanoparticles deposited on top of the TiO2-passivated GaP further increases the photoconversion efficiency through local field enhancement. These two enhancement mechanisms are separated by systematically varying the thickness of the TiO2 layer. Because of the tradeoff between the quickly decaying plasmonic fields and the formation of the pn-charge separation region, an optimum performance is achieved for a TiO2 thickness of 0.5 nm. Finite difference time domain (FDTD) simulations of the electric field profiles in this photocatalytic heterostructure corroborate these results. The effects of plasmonic enhancement are distinguished from the natural catalytic properties of Au by evaluating similar photocatalytic TiO2/GaP structures with catalytic, non-plasmonic metals (i.e., Pt) instead of Au. This general approach of passivating narrower band gap semiconductors enables a wider range of materials to be considered for plasmon-enhanced photocatalysis for high efficiency water splitting.
Nonparaxial one-dimensional spatial solitons.

Scalar and vector nonlinear nonparaxial evolution equations are developed for propagation in two-dimensions. Using standard soliton scalings, it is found that nonparaxial propagation is accompanied by higher-order linear and nonlinear terms and an effective quintic nonlinear index. The presence of an intrinsic quintic nonlinearity arising from χ(5) must also be considered at the order of the analysis. These terms represent corrections to the well-known nonlinear Schrodinger equation. Exact and approximate solutions to these higher-order evolution equations are obtained and are shown to exhibit quasi-soliton behavior based on propagation and collision studies.
Immunoglobulin transport across polarized epithelial cells.

IgA, IgG and IgM are transported across epithelial cells in a receptor-mediated process known as transcytosis. In addition to neutralizing pathogens in the lumen of the gastrointestinal, respiratory and urogenital tracts, these antibody–receptor complexes are now known to mediate intracellular neutralization of pathogens and might also be important in immune activation and tolerance. Recent studies on the intracellular transport pathways of antibody–receptor complexes and antibody-stimulated receptor-mediated transcytosis are providing new insight into the nature and regulation of endocytic pathways.
Communications skills and moral principles in health care: Aspects of their relationship and implications for professional education

Abstract There are critical points of convergence between the major moral principles in health care and the requirements for effective communications skills. Developments in these fields have proceeded in relative isolation from each other, with the result that health professions' students often learn ethical principles in the abstract, without clear understanding of their implications for caring behaviors in the clinic. Similarly, communications skills instruction often lacks the firm intellectual foundations that ethics and humanities perspectives can provide. The moral principles that are discussed are beneficence and nonmaleficence, respect for persons, and justice . The overlap and mutual reinforcement between these principles and skills in clinical practice requires collaborative educational efforts by ethics and humanities faculty, communications experts, and clinicians.
Relationship of folate to colorectal and cervical cancer: review and recommendations for practitioners.

Abstract Evidence suggests that folate may play a role in cancer prevention. A plausible mechanism for prevention lies in the integral role that folate plays in deoxyribonucleic acid (DNA) synthesis and methylation. DNA methylation most likely regulates gene expression. Abnormal methylation, specifically hypomethylation, has been associated with tumorigenesis. The availability of methyl groups needed for adequate DNA methylation may be negatively influenced by low folate status, alcohol intake, or genetic polymorphisms that affect folate metabolism. Observational studies evaluating the association between folate and risk for colorectal and cervical cancers or precancerous conditions have produced conflicting results, and clinical trial data are needed to confirm a cause-and-effect relationship. However, several studies show interesting associations between cancer risk and factors that influence methyl group availability. Although data relating folate to cancer risk remain equivocal, when coupled with the other potential health benefits associated with folate, evidence supports recommending that people consume folate-rich foods such as fruits and vegetables. People consuming alcohol on a daily basis may especially benefit from additional folate in their diets. J Am Diet Assoc. 2002;102:1273–1282 .
Transamination reactions with multiple turnovers catalyzed by hydrophobic pyridoxamine cofactors in the presence of polyethylenimine polymers

Pyridoxamines carrying hydrophobic side chains reversibly bind into the hydrophobic core of polyethylenimines and transaminate ketoacids to amino acids with as much as a 725000-fold rate acceleration. Turnover catalysis was achieved by sacrificial oxidative decarboxylation of C-substituted amino acids, which reconverted the pyridoxals to pyridoxamines.
Intrafetal radiofrequency ablation for twin reversed arterial perfusion (TRAP): a single-center experience

Objective The objective of the study was to review perinatal outcomes in pregnancies treated with intrafetal radiofrequency ablation (RFA) for twin reversed arterial perfusion (TRAP) sequence. Study Design Perinatal outcome data from a quaternary care referral center were abstracted from a chart review of pregnancies with TRAP sequence treated in the midtrimester with umbilical cord RFA of the perfused twin. Results Twenty-one pregnancies with TRAP sequence were evaluated. Two women had a pump twin demise prior to therapy, 1 with trisomy 21 declined treatment. Four of 20 were treated successfully with RFA but remain undelivered, and 1 was treated with fetoscopic cord coagulation. Twelve of 13 pump twins treated with RFA (94%) survived to 30 days of life. Mean preoperative cardiac combined cardiac output was 588 mL/kg and pump/twin ratio was 0.7 (range 0.4 to 1.1). The effect of RFA on postoperative cardiac output was variable (6-85%). The average gestational age at birth was 37 weeks (range 26-39 weeks). Conclusion Primary therapy with RFA is a successful modality for pregnancies complicated by TRAP sequence.