cssi/SciSciGPT-SciSciNet huggingface dataset:
Measurement of Acetate Concentrations in Marine Pore Waters by Using an Enzymatic Approach

Acetate concentrations in marine and freshwater matrices were measured by an enzymatic technique which coupled the synthesis of acetyl coenzyme A to AMP production. The resulting AMP was assayed by a sensitive and relatively rapid high-pressure liquid chromatography method, using an aqueous, isocratic mobile phase for elution. The method was insensitive to the presence of seawater salts and required no sample prepurification or distillation. Propionate caused a minor, but statistically insignificant, interference when equimolar with acetate; butyrate caused no interference, even at relatively high concentrations. Detection limits for acetate were approximately 100 nM with a precision of about 5%. Pore waters from two intertidal sediments contained approximately 1 to 12 muM acetate; the concentrations were linearly but inversely correlated with porewater sulfate.
Practical Considerations in the Synthesis of High Performance Digital Filters for Implementation on FPGAs

The quality of a hardware implementation of a digital filter should be measured in terms of both hardware measures such as hardware cost, throughput and latency, and quality of performance measures such as the degree to which the implemented filter's frequency response matches a stated ideal. Here, practical considerations for the implementation of high performance digital filters on field programmable gate arrays are outlined, and the effect of design and implementation decisions on both hardware and quality of performance measures are considered. A synthesis system for high performance digital filters is described. Results show that the synthesized filters are slightly smaller than and have twice the throughput of comparable filters synthesized with Altera's FIR Compiler Megacore Function.
Educational Leadership: a Focus on Teacher-Student Interaction

Real leaders know that if the schools they lead are to be successful, the teachers must be successful. And that goes beyond helping them hone their instructional skills, says this writer.
Hormone therapy for the prevention of bone loss in menopausal women with osteopenia: is it a viable option?

Osteopenia is a state of low bone mass, the appropriate clinical management of which is not always clear. The use of hormone therapy for postmenopausal bone loss has become controversial given recent data regarding the risks of therapy. Fragility fractures are common, and result in substantial morbidity and mortality. Although the fracture rate is higher among osteoporotic women, the substantially larger population of osteopenic women accounts for a higher absolute number of fractures. Osteopenia is defined solely according to the statistical properties of the distribution of bone mineral density (BMD) values, which limits its usefulness in clinical care. BMD, although inversely related to fracture risk, should not be used as the sole criterion for fracture risk. Limited data suggest that benefits of treatment seen in women with documented osteoporosis may not extend to osteopenic women. Although estrogen prevents postmenopausal bone loss, preservation of BMD does not necessarily translate into reduced fracture risk. In making decisions about whether to treat a woman with osteopenia, it is critical to estimate how treatments will affect the individual’s risk of fracture. Treatment decisions should be based on whether the net benefits of treatment outweigh the anticipated risks, which will depend on the age of the patient and her risk profile. In our opinion, there is insufficient evidence to support treatment for women with a BMD in the osteopenic range in the absence of fragility fracture. For osteopenic women with higher risk, the availability of other treatments with a more favourable risk-benefit profile eliminates the role of hormone therapy for fracture prevention.
Uncertainty propagation via multi-element grid

In this paper, a new method named multi-element grid (MEG) is proposed to solve the uncertainty propagation problem. The MEG can be used for arbitrary probability distributions. In addition, the number of points and accuracy can be flexibly controlled. The proposed method is compared with the Monte Carlo method, the Gauss-Hermite quadrature (GHQ), and the sparse-grid quadrature (SGQ) via the Lorenz problem. The simulation results show that the new proposed MEG method provides more accurate results than the GHQ and the SGQ, and is computationally more efficient than the Monte Carlo method.
Simultaneous quantification of nicotine, cotinine, trans-3'-hydroxycotinine, norcotinine and mecamylamine in human urine by liquid chromatography-tandem mass spectrometry.

Abstract Background Mecamylamine is a nicotine antagonist under investigation in combination with nicotine replacement for smoking treatment. Methods A simple, rapid and reliable liquid chromatography tandem mass spectrometry (LCMSMS) method was developed and validated for quantifying nicotine, cotinine, trans-3′-hydroxycotinine, norcotinine and mecamylamine in human urine. Chromatography was performed on a Synergi PolarRP column with a gradient of 0.1% formic acid and 0.1% formic acid in acetonitrile at 0.25 ml/min with an 8-min total runtime. Analytes were monitored by positive mode electrospray ionization and multiple reaction monitoring mass spectrometry. Results Linear dynamic ranges were 1–500 ng/ml for nicotine and norcotinine, 0.5–500 ng/ml for trans-3′-hydroxycotinine, 0.2–500 ng/ml for cotinine, and 0.1–100 ng/ml for mecamylamine; correlation coefficients were consistently greater than 0.99, and all calibrator concentrations were within 20% of target. Extensive endogenous and exogenous interferences were evaluated. At 3 concentrations spanning the linear dynamic range of the assay, mean extraction efficiencies from urine were 55.1–109.1% with analytical recovery (bias) 82.0–118.7% and total imprecision of 0.7–9.1%. Analytes were stable for 24 h at room temperature, 72 h at 4 °C, 72 h in autosampler at 15 °C and after three freeze/thaw cycles. Conclusion This method is useful for monitoring mecamylamine, nicotine and nicotine metabolites in smoking cessation and other clinical nicotine research.
Shoulder arthroplasty in morbidly obese patients.

Background The purpose of this study was to determine the results, complications, and failure rates of shoulder arthroplasty in morbidly obese patients. Methods Between 1994 and 2005, 45 shoulder arthroplasties were performed for osteoarthritis in patients with a BMI greater than 40. Forty-one shoulders were followed for a minimum of 2 years (mean, 55 months) or until revision. Results Shoulder arthroplasty in morbidly obese patients was associated with improvement in pain and range of motion (P ≤ .001). Average operative time was 220 minutes (range, 152-337). Four required anteromedial approaches. There was 1 intraoperative humeral shaft fracture and 2 small anterior deltoid avulsions. Five patients required overnight ICU monitoring. Average length of stay was 3.1 nights (range, 2-5). One shoulder developed a superficial infection while 1 patient had wound healing difficulty. Five shoulders underwent revision arthroplasty: 2 deep periprosthetic infections, 1 hemiarthroplasty for glenoid arthritis, 1 for posterior instability, and 1 for glenoid loosening. The Kaplan-Meier estimate for survival free of revision was 92.1% at 5 years. Conclusions Shoulder arthroplasty in the morbidly obese is associated with long-term improvement in pain and function. However, the intraoperative and postoperative care of these patients is more complex, and these patients seem to have a higher rate of unsatisfactory results. Level of evidence Level 4; Case series, treatment study.
Do ATP4− and Mg2+ bind stepwise to the F1-ATPase of Halobacterium saccharovorum ?

It is commonly believed that MgATP2− is the substrate of F1-ATPases and ATP4− acts as a competitive inhibitor. However, the velocity equation for such competitive inhibition is equivalent to that for a rapid equilibrium ordered binding mechanism in which ATP4− adds first and the binding of Mg2+ is dependent on the formation of the E ATP4− complex. According to this ordered-binding model, solution formed MgATP2− is not recognized by the ATPase as a direct substrate, and the high-affinity binding of Mg2+ to the E ATP4− complex is the key reaction towards the formation of the ternary complex. These models (and others) were tested with an F1- ATPase, isolated from Halobacterium saccharovorum, by evaluating the rate of ATP hydrolysis as a function of free [ATP4−] or free [Mg2+]. The rates were asymmetrical with respect to increasing [ATP4−] versus increasing [Mg2+]. For the ordered-binding alternative, a series of apparent dissociation constants were obtained for ATP4− (.cf2.K.cf2..cf1..esapp.rb.eiA.rb), which decreased as [Mg2+] increased. From this family of .cf2.K.cf2..cf1..esapp.rb.eiA.rb the true KA was retrieved by extrapolation to [Mg2+] = 0 and was found to be 0.2 mM. The dissociation constants for Mg2+, established from these experiments, were also apparent (.cf2.K.cf2..cf1..esapp.rb.eiB.rb) and dependent on [ATP4−] as well as on the pH. The actual KB was established from a series of .cf2.K.cf2..cf1..esapp.rb.eiB.rb by extrapolating to [ATP4−] = ∞ and to the absence of competing protons, and was found to be 0.0041 mM. The pKa of the protonable group for Mg2+ binding is 8.2. For the competitive inhibition alternative, rearrangement of the constants and fitting to the velocity equation gave an actual binding constant for MgATP2− (KEAB) of 0.0016 mM and for ATP4− (KEA) of 0.2 mM. Decision between the two models has far-reaching mechanistic implications. In the competitive inhibition model MgATP2− binds with high affinity, but Mg2+ cannot bind once the E ATP4− complex is formed, while in the ordered-binding model binding of Mg2+ requires that ATP4− adds first. The steric constraints evident in the diffraction structure of the ATP binding site in the bovine mitochondrial F-ATPase [Abrahams, J. P., Leslie, A. G. W., Lutter, R. & Walker, J. E. (1994) Nature 370, 621−628] tend to favor the ordered-binding model, but the final decision as to which kinetic model is valid has to be from further structural studies. If the ordered-binding model gains more experimental support, a revision of the current concepts of unisite catalysis and negative cooperativity of nucleotide binding will be necessary.
Application of artificial intelligence methods to intramolecular dynamics calculations

The application of artificial intelligence (AI) methods to the determination of intramolecular quantum dynamics for multidimensional systems is described. An AI method based on a physically motivated search algorithm and evaluation function is considered. In both the cases of quantum beats and energy “dissipation” the results for the intramolecular vibrational energy redistribution within an eleven-coordinate model system are shown to be accurate with a considerably reduced number of basis states.
HIGH INCIDENCE OF HYPERTENSION (HTN) DURING STATUS ASTHMATICUS (SA) IN CHILDREN. 2287

Incidence of HTN, a potential morbidity factor, among Asthmatics is unknown. An occasional observation of Systolic (SYS) HTN led us to evaluate the BP of 61 pts with SA (mean age 6.0 yrs) and 42 control (mean age of 5.0 yrs) hospitalized in PICU patients for 3 days. Value of 95% tile was used to define in HTN. All patients with SA received steriods B agonists inhalation and theophyllin. Number (%) with HTN in the 2 groups are compared(Table).
A Three-Layer Modeling for Cuttings Transport with Coiled Tubing Horizontal Drilling

A new approach of three-layer flow of two-phase (solid-liquid) fluid in annulus, i.e. a stationary bed of drilled cuttings at bottom; a moving bed layer above it: and a heterogeneous suspension layer at the top, is proposed to predict and interpret the cuttings transport mechanism. This new mathematical model is presented to overcome the limitation in the existing two-layer models. This enables efficient prediction of cuttings transport during horizontal drilling using coiled tubing. In particular, the model described in this paper formulates transport process and includes the relevant parameters such as rheological characteristics of the drilling fluid, cuttings size/sphericity/ concentration, wellbore geometry, eccentricity of the coiled tubing, and pumping rate of the drilling fluid. This paper presents the model development, solution. and simulation of the cutting transport process to illustrate the steps involved in determining the effect of each parameter during the drilling operation. Graphical charts and developed correlations between annular flow rate, rheology, wellbore geometry, eccentricity, cuttings size and concentration in each layer, and the carrying capacity are also presented. The simulation results show how to obtain a reasonable pumping velocity of drilling fluid with the possible lowest pressure gradient that might serve as an operational guideline during drilling. Furthermore, the effects of parameters affecting the efficiency of cutting transport are discussed. These results are compared with published experimental data. The observed agreement and discrepancies are discussed, and further improvements on the current model are proposed.
Hot tub legionellosis. Legionnaires' disease and Pontiac fever after a point-source exposure to Legionella pneumophila.

Legionella pneumophila is associated with outbreaks of either Pontiac fever, a self-limited influenzalike condition without pneumonia, or Legionnaires' disease, a severe pneumonic disease affecting elderly or immunocompromised individuals. An outbreak of both Legionnaires' disease and Pontiac fever after a point-source exposure to L pneumophila was studied. Our observations demonstrated the spectrum of illness that L pneumophila may cause and emphasized the importance of host factors in affecting the expression of infection. (Arch Intern Med. 1993;153:2597-2599)
Bistable storage in pulsed gate-controlled diodes

It is shown that all ordinary MOS gate-controlled diode can exhibit bistability if periodically pulsed via a resistor. The bistability is due to a regenerative interaction between the charge-pumping action and the source-voltage dependence of the gate capacitance. This extremely simple structure stores binary data in the form of charge across the source-substrate junction capacitance by compensating for the junction leakage current. No DC power is dissipated in any of the stable states. An analysis of the bistable operation is provided and its possible application to the bistabilization of dynamic RAM cells is discussed. >
Characterization of Two Protein Activities That Interact at the Promoter of the Trypanosomatid Spliced Leader RNA

Abstract All trypanosome mRNAs have a spliced leader (SL). The SL RNA gene in Leptomonas seymouri is a member of the small nuclear RNA gene family. However, the SL RNA is required in stoichiometric amounts for trans-splicing during mRNA formation. Expression of the SL RNA gene requires sequence elements at bp −60 to −70 and bp −30 to −40 upstream from the transcription initiation site. Using conventional and affinity chromatography, we have identified and characterized an ∼122-kDa protein, promoter-binding protein (PBP) −1, that binds to double-strand DNA. The PBP-1-binding site is within the bp −60 to −70 element determined by DNase I footprinting. Therefore, PBP-1 is the first characterized double-strand DNA binding activity that interacts with a trypanosome gene promoter. A second protein, PBP-2, interacts with the PBP-1:DNA complex and its DNase I footprint extends to include the second promoter element (bp −30 to −40). An alteration of the spacing between the two promoter elements or mutation of the second element decreases PBP-2/PBP-1:DNA stability. Taken together, these data suggest that PBP-1 and PBP-2 are components of a transcription initiation complex that assembles within the SL RNA gene promoter.
Core binding-energy shifts for free negative ions of oxygen: O0 to O2−

Abstract The free-ion 1 s binding-energy shifts for oxygen anions are investigated as a function of anionic charge. The ΔSCF method is used for calculation
Design and Testing of a Robotic System for mr Image-guided Interventions

The effective integration of robotics together with magnetic resonance (mr) technology is expected to facilitate the real-time guidance of various diagnostic and therapeutic interventions. Specially designed robotic manipulators are required for this purpose, the development of which is a challenging task given the strong magnetic fields and the space limitations that characterize the mr scanning environment. A prototype mr-compatible manipulator is presented, designed to operate inside cylindrical mr scanners. It was developed for the study of minimally invasive diagnostic and therapeutic interventions in the abdominal and thoracic area with real-time mr image guidance. Initial tests were performed inside a high-field clinical mr scanner and included mr-compatibility tests and phantom studies on image-guided targeting.
Immobilization of proteins on organic polymer beads

A new method is described for the immobilization of biologically active proteins onto several types of organic polymer beads. First, the soluble protein is modified by reaction with an excess of a hydrophobic imidoester, for example methyl 4-phenyl-butyrimidate, at ca. pH 9 and 0 degrees . Excess imidoester and side products resulting from imidoester hydrolysis are separated from the hydrophobic protein derivative by exclusion chromatography or dialysis. A suspension of polymer beads (e.g. Amberlite XAD-7) is then added to a solution of the modified protein at room temperature or below and stirred gently for 1-2 h. The polymer beads are allowed to settle, separated from the solution by decantation or filtration, washed, and resuspended in an appropriate buffer. Quantitative adsorption of protein to the polymer beads is observed under such conditions. The synthesis of seven hydrophobic imidoesters and their use for the immobilization of trypsin onto several types of porous polymer beads is described. The immobilizations of trypsin, yeast alcohol dehydrogenase, and E. coli asparaginase by this procedure with high recoveries of catalytic activity, suggests that it will be applicable to a large number of biologically active proteins.
Mathematical analysis of a model for a plant-herbivore system

The apple twig borer (Amphicerus bicaudatus) is an insect pest of the grape vine, causing considerable damage to the grape vine in early spring. A simple difference equation model is formulated and analysed for this plant-herbivore system based on two control strategies, cane removal and pesticide application. The system has two equilibria, one where the pest is present and one where the pest is absent. Regions are found in parameter space for global stability of the equilibria and in the absence of global stability it is shown that there exist periodic or quasiperiodic solutions.
H i Absorption toward Cooling Flows in Clusters of Galaxies

An H I survey of 14 cooling flow clusters and two noncooling flow clusters was conducted, and H I absorption features were detected against the nuclear radio continuum sources of two cooling flow dominant (CFD) galaxies, 2A 0335 + 096 and MKW3s. The absorption features are broad and redshifted with respect to the stellar absorption-line velocity of the CFDs by 90-225 km/s. This indicates that the H I is falling onto, and is probably gravitationally bound to, the CFDs. The kinematics of the H I clouds suggest a possible kinematic link between the warm and cold phases of the intracluster medium. The clouds are orders of magnitude smaller in radius and mass and larger in density than Galactic H I clouds. The detected CFDs have mass-accretion rates that are about 2.5 times larger than the CFDs that were not detected.
The development of resistance to carcinogen-induced cytotoxicity in hamster embryo cultures

Abstract This investigation was supported in part by USPHS Research Grants Nos. CAO4534 and CAO8936 from the National Cancer Institute and Research Grant No. E-89 1 from the American Cancer Society. Dr Brookes' contribution to this work was carried out in the laboratory of Prof. C. Heidelberger, McArdle Laboratory, University of Wisconsin, Madison, during the tenure of an Eleanor Roosevelt International Cancer Fellowship of the American Cancer Society awarded by the International Union Against Cancer. We acknowledge the excellent technical assistance of Miss R. McFall.
EYA1 and SIX1 drive the neuronal developmental program in cooperation with the SWI/SNF chromatin-remodeling complex and SOX2 in the mammalian inner ear

Inner ear neurogenesis depends upon the function of the proneural basic helix-loop-helix (bHLH) transcription factors NEUROG1 and NEUROD1. However, the transcriptional regulation of these factors is unknown. Here, using loss- and gain-of-function models, we show that EYA1 and SIX1 are crucial otic neuronal determination factors upstream of NEUROG1 and NEUROD1. Overexpression of both Eya1 and Six1 is sufficient to convert non-neuronal epithelial cells within the otocyst and cochlea as well as the 3T3 fibroblast cells into neurons. Strikingly, all the ectopic neurons express not only Neurog1 and Neurod1 but also mature neuronal markers such as neurofilament, indicating that Eya1 and Six1 function upstream of, and in the same pathway as, Neurog1 and Neurod1 to not only induce neuronal fate but also regulate their differentiation. We demonstrate that EYA1 and SIX1 interact directly with the SWI/SNF chromatin-remodeling subunits BRG1 and BAF170 to drive neurogenesis cooperatively in 3T3 cells and cochlear nonsensory epithelial cells, and that SOX2 cooperates with these factors to mediate neuronal differentiation. Importantly, we show that the ATPase BRG1 activity is required for not only EYA1- and SIX1-induced ectopic neurogenesis but also normal neurogenesis in the otocyst. These findings indicate that EYA1 and SIX1 are key transcription factors in initiating the neuronal developmental program, probably by recruiting and interacting with the SWI/SNF chromatin-remodeling complex to specifically mediate Neurog1 and Neurod1 transcription.
Paradise to parking lots: Creation versus maintenance of a public good

Abstract We offer further evidence that experiment framing significantly influences subject behavior. A Public Bad game strategically equivalent to the traditional Public Good game is designed. The Public Bad game is intended to simulate the decision to pollute or not pollute, a context that is likely to be more familiar to our subjects than those of previous studies. We find that subjects are more likely to take actions, at some cost to themselves, to create benefits for the group than they are to be inactive, at some cost to themselves, to create the same benefits for the group.
Evidence for Increased Bone Formation Following a Brief Endurance-Type Training Intervention in Adolescent Males

The effect of exercise training, particularly relatively brief periods, on bone turnover markers in adolescents has been poorly studied. Thirty-eight healthy males (16+/-0.7 years) participated in a 5-week summer school program in which 20 subjects were randomly assigned to a training group consisting of 2 h/day, 5 days/week of endurance exercise, and 18 subjects were assigned to a control group. Bone formation was assessed by measurements of circulating osteocalcin, bone-specific alkaline phosphatase (BSAP), and the C-terminal procollagen peptide (PICP). Bone resorption was assessed by urinary levels of free deoxypyridinoline cross-links (dPYR) and the C-(CTX) and N-terminal (NTX) telopeptide cross-links. Prior to training, there was a weak positive correlation between fitness and PICP (r = 0.27, p < 0.05), but no correlations were observed between fitness and either the other markers of bone formation or bone resorption. Training led to a significant increase in (1) osteocalcin (15+/-4%, p < 0.03), (2) BSAP (21+/-6%, p < 0.02), and (3) PICP (30+/-11%, p < 0.03) and to a significant decrease in NTX (-21 +/- 3%, p < 0.05). These bone turnover markers did not change in the control subjects (osteocalcin, 0+/-4%; BSAP, 2+/-4%; PICP, -4 +/- 6%; NTX, -6 +/- 4%). There was no change in urinary dPYR and CTX in either control or trained subjects. Fitness is only weakly, if at all, correlated with bone formation, but a relatively brief period of endurance training leads to a substantial increase in bone formation markers in adolescent males. School-based, short-term exercise training programs could play a role in enhancing bone formation in adolescents.
Formation and prevention of agglomerated deposits during the gasification of high-sodium lignite

A high-sodium lignite from the Freedom mine in North Dakota was tested in the transport gasifier at the Power Systems Development Facility (PSDF). During the first use of the high-sodium lignite in October 2003, agglomerated deposits formed at various locations in the transport gasifier system. An extensive laboratory testing program was carried out to characterize the deposits, understand the mechanism of the deposit formation, and test various methods of preventing or minimizing the agglomeration. The results of the deposit analysis and initial lab studies suggested that sodium released from the lignite was deposited on the surface of the sand bed material, resulting in the formation of sticky sodium silicates. Additional laboratory tests indicated that the agglomeration could be avoided or minimized by replacing the sand with a nonreactive bed material (e.g., coarse coal ash), operating at slightly reduced temperatures and using certain types of additives. By using these procedures, we completely elimi...
An effective Lagrangian for dynamically broken gauge theories

Abstract Dynamical symmetry breaking in non-abelian gauge theories is studied by computing an effective potential for composite operators. We obtain consistent solutions of chiral and gauge symmetry breaking which are, in some cases, compatible with a short distance behavior. The effective theory determined is in agreement with the tumbling hypothesis.
Mechanism of microsomal mixed-function oxidase inhibitor from the housefly Musca domestica L

Abstract An inhibitor of microsomal mixed-function oxidase activity from the head of the housefly, Musca domestica L., has been partially purified by chromatography on Sephadex G-25. Its chemical characteristics, in agreement with investigations from other laboratories, indicate that it is the eye pigment, xanthommatin. The inhibitory mechanism has been investigated using microsomal preparations from mouse liver and housefly abdomens as well as a purified microsomal NADPH-cytochrome c reductase from the housefly. Kinetic expriments on the rate of p-nitroanisole demethylation, NADPH oxidation, and cytochrome c reduction indicate that the inhibitor acts by accepting electrons at the reductase level thus impeding electron flow to cytochrome P-450. The inhibitor will accept electrons from the purified NADPH-cytochrome c reductase and also stimulate the reduction of cytochrome c by this enzyme. Spectral studies of cytochrome b5 and cytochrome P-450 show that the inhibitor can prevent the reduction of cytochrome b5, presumably by accepting electrons prior to the cytochrome level, but does not interact with cytochrome P-450 nor does it affect the binding of other substrates to this cytochrome.
Multiple Roles and Psychological Well-Being

Abstract Role theory generally views the performance of multiple roles as a source of psychological stress. Recently, however, the concept of role strain resulting from multiple roles has been criticized. Marks (1977) and Seiber (1974) argue that multiple roles may lead to positive personal well-being. The present research is a test of these recent ideas. Measures of subjective well-being are correlated with the quantity and quality of roles enacted. Five role spheres are specified: Spouse, parent, worker, friend, and church member. The findings offer some support for the proposition that involvement in multiple roles does not necessarily lead to role strain. Instead, well-being increases with the number of roles enacted, and satisfaction in one role can help to compensate for deprivation in another role sphere. Support is thus found for both Marks' (1977) “expansionist” theory and Seiber's (1974) role accumulation theory.
Infiltration of fiber preforms by a binary

In a previous article, [1] a theoretical analysis was developed to describe the infiltration of fiber preforms by a binary alloy, and its solution was given for unidirectional adiabatic infiltration under constant applied pressure. This article further develops the analysis by proposing a model to predict the permeability of fibrous preforms containing solidified primary metal, by deducing the final composite microstructure from processing parameters, and by addressing the influence of external cooling on macrosegregation within the composite. Experimental procedures estab- lished for the infiltration of fiber preforms by pure aluminum are modified to produce samples infiltrated under nearly adiabatic conditions. Samples of SAFFIL alumina fiber preforms infil- trated adiabatically under constant applied pressure with Al-4.5 wt pct Cu show longitudinal variations in copper concentration, which are well predicted by theory presented in Part I. [1] The microstructures in the infiltrated composite samples also agree with analysis: the grain size is small where solid and liquid matrix coexisted during infiltration, whereas it is large where remelting occurred, indicating that SAFFIL fibers do not promote nucleation of Al-Cu. The model proposed here for permeability of the preform in the presence of solidified metal yields infiltration rates in agreement with experimental data. Finally, samples produced under non- adiabatic conditions exhibit transverse macrosegregation; this is explained for simple limiting cases of heat transfer at the die wall.
Subleading corrections to the |Vub| determination from exclusive B decays

Abstract It has been proposed to determine the CKM matrix element |Vub| in a model-independent way from a combination of rare and semileptonic B and D decays near the zero recoil point. An essential ingredient in such a determination is a heavy quark symmetry relation connecting the form-factors appearing in B→K ∗ e + e − to semileptonic form factors relevant for B→ρeν. We estimate the leading corrections to this symmetry relation, of order αs(mb) and Λ/mb, pointing out that they can be as large as 20%, depending on the value of the matrix element of a dimension-4 operator. Dimensional analysis estimates of this matrix element give a corresponding uncertainty in |Vub| of the order of a few percent.
A Measure of Hope in Franchise Systems: Assessing Franchisees, Top Executives, and Franchisors

The current study examines the hope level of franchisees, top level executives, and franchisors to add to our understanding of the construct in improving overall motivation that could improve how franchises are managed. The concept of hope is a psychological construct that has been studied thoroughly in the academic and athletic areas, as well as in the psychological literature. It has not been studied in the context of franchising. The relationship between entrepreneurship, franchising, and organizational behavior is discussed and future studies explored.
Measurement and utilization of on-site soil moisture data

Programs for the on-site measurement of soil moisture in the USA are reviewed. These are regional and national measurement programs that may be useful for the verification of remotely sensed soil moisture estimates and for hydroclimatic studies. Location and type of measurement are described. A technique for the utilization of on-site data of soil moisture and discharge together with remotely sensed data of the surface soil moisture is proposed for the estimation of soil water content aggregated over large areas. The technique is based on large-scale conceptual hydrologic models and on state estimation techniques that allow explicit account to be taken of measurement uncertainty. The proposed approach is explored in an example formulation applied to a 40 year record of monthly data from a 4672 km2 natural catchment in Illinois. This study shows the ability of simple conceptual hydrologic models to simulate well both flow and soil water in humid areas and with monthly data. It is further shown that, even when the remotely sensed measurements of the surface soil moisture carry substantial measurement errors, inference of lower soil water and of total soil water is possible with an expected error that is smaller than that achieved without the use of the remotely sensed data.
The relationship between osmolality and electrolytes in rat gastric juice following histamine and insulin hypoglycaemia

Abstract In chronic gastric fistula rats hourly gastric juice collections were made before and after subcutaneous injections of histamine and insulin. Linear relationships were obtained between gastric juice osmolality and H + and Cl − ion concentrations. These relationships were independent of the type of the stimulant used. The osmotic effects of the individual gastric juice electrolytes were calculated. The contribution of the non-electrolyte component was greater than 50% of the total gastric juice osmolality. Apart from the first hour after stimulation, close correlation existed between the Na + and H + ion concentrations. Close correlation was apparent between the H + ion concentration and that of total and neutral chloride at all time periods.
WE‐D‐330A‐07: The Small‐Animal Radiation Research Platform (SARRP): Focused Pencil Beam Dosimetry

Purpose: A small animal radiation platform equipped with on‐board conebeam CT and conformal irradiation capabilities is being constructed for translational research. This work reports on the dosimetric characteristics of the x‐ray lens subsystem used for high‐resolution dose delivery. Method and Materials: A constant voltage 225 kVp x‐ray beam from a 0.4 mm focal spot is shaped and directed to enter a 1.5 cm long, 2 cm diameter cylindrical multi‐layer graphite x‐ray lens placed 16 cm downstream from the source. The lens emits a converging circular beam of 40–80 keV x‐rays which forms a narrow cylindrical beam centered at 33.5 cm downstream with a length of approximately 5 cm in air. The pencil beam disperses further downstream. We measured dosimetry of the beam in water equivalent plastic using Gaf‐chromic EBT films (<0.1 mm pixel size) over a SSD range of 30 to 33.5 cm in steps of 5 mm. For each SSD, 36 films were orientated orthogonal to the beam and at every 2 mm between slabs in the depth direction. We established the optical density‐to‐dose calibration with a 6 MV beam. Results: The beam has a highly peaked cross‐beam profile with a full width half maximum of about 1.5 mm in the focal zone. Irregular cylindrical symmetry is present due to imperfect lens construction. Dose deposition was defined as the average value over a circular area with a diameter of 1.5mm from the beam axis. Surface dose rates are 230 – 160 cGy/min over the 3.5 cm range of SSDs. The percent depth dose is approximately 34% at 2 cm depth for a beam at 33.5 cm SSD. Conclusion: Highly localized dose can be delivered with the focused pencil beam. Work is on‐going to improve dose uniformity by lens rotation, and to develop a pencil beam algorithm for planning purposes.
Mechanism of Dissimilar Metal Crevice Corrosion of Superferritic Stainless Steels

Abstract Superferritic stainless steels (SS) can suffer from dissimilar metal crevice (DMC) corrosion when part of a crevice with certain other stainless alloys. For example, UNS S44735 is attacked when part of a crevice with type 316 SS (UNS S31600) but not when part of a crevice with type 304 SS (UNS S30400). To understand this phenomenon better, solutions which form inside such crevices were collected and analyzed with ion chromatography and capillary electrophoresis for their metal ion content. These analyses provided the data required to design bulk solutions for electrochemical kinetics measurements. Electrochemical measurements in these simulated crevice solutions were compared to measurements made in simple hydrochloric acid (HCl) solutions. The simulated crevice solutions were much more aggressive toward the materials than the simple HCl solutions. The superferritic SS was depassivated more easily in the simulated crevice solutions and exhibited a much larger active-to-passive transition in these...
1009-50 Pseudo Atrioventricular and Ventriculoatrial Block Induced by Radiofrequency Ablation of Several Atrio-AV Nodal Connections

We determined the roles of the various atrial(A)-atrioventricular nodal (AVN) connections in AV and VA conduction by sequential radiofrequency (RF) ablation. In prior studies, RF ablation applied epicardially to the “fast” pathway (FP) induced A-His bundle (Hb) area delay ≥40 msec and the shift of retrograde A activation from the Hb area to the area of the coronary sinus (CS) ostium, “slow” pathway (SP). Subsequent SP ablation significantly increased the A-H interval, ≥70 msec, and caused VA block in g50%. Histology showed an intact AVN and ablation of its posterior input. In this study, 6 dogs, FP and SP were ablated by the same epicardial approach. Complete AV and VA block were observed in only 1 of 6 dogs. In another 9 dogs, a third lesion was placed endocardially from the fossa ovalis to the entrance of the inferior vena cava, in addition to FP and SP ablation, causing complete AV and VA block in 5 of 9 dogs. During block, a stable AV junctional escape rate (58 ± 10/min) appeared, indicating a supra-hisian pacemaker. In 1 case of “AV block”, pacing from the A close to the Hb showed 1: 1 A-Hb-V conduction up to a rate of 200/min. In addition, there was 1: 1 retrograde conduction to the high right (HR) A with marked conduction delay. In 2 other cases, there was 1: 1 V-HbA conduction during RV pacing, but HRA and CSA electrograms were dissociated. Postmortem, the AV junction showed that all radiofrequency lesions bordered the triangle of Koch. We conclude that there are multiple atrio-AVN connections which provide back-up mechanisms to prevent combined AV and VA block in the normal heart. Moreover, ablation of two or more A inputs can result in pseudo AV and VA block, since some A remains connected to a functional AVN and Hb.
Stochastic Network Models for Survival Analysis

Abstract We present methodology giving highly accurate approximations for Bayesian predictive densities and distribution functions of first passage times between states of a semi-Markov process with a finite number of states. When the states describe a degenerative disorder with an absorbing end state, such predictive distributions are the survival distributions of a patient. We illustrate these methods with a variety of examples, including data from the San Francisco AIDS study. We achieve our approximations using a three-step sequence. First, we introduce advanced concepts of flowgraph theory, which allow us to compute the moment generating function of the first passage time given the model parameters. Next, we use saddlepoint approximations to convert this into a density or distribution function conditional on the model parameter. Finally, we use Monte Carlo methods to remove dependence on the model parameter. These methods apply quite generally to all finite-state semi-Markov models in discrete or con...
Tri- to be Mono- for Bacterial mRNA Decay

Messing et al. (2009) report the homodimeric structure of the Bdellovibrio bacteriovorus RppH pyrophosphohydrolase, which hydrolyzes the mRNA 5′ triphosphate to initiate bacterial mRNA decay. These structures reveal insights into BdRppH substrate recognition and analogies to eukaryotic decapping enzymes.
Investigations into the minimization of electrical costs for traction-type elevators

This work examines the real-time utilization of energy in an operating elevator drive system with a goal, not of improving efficiency per se, but rather of reducing the cost paid by the system owner for the operation of the equipment. Several load-leveling and peak-shaving schemes using ultracapacitors are reviewed, including (1) off-peak energy storage for on-peak use, (2) energy storage to reduce the utility demand cost, (3) energy storage to reduce inrush peaks, and (4) energy storage to redirect regenerated energy. Each of these schemes is developed to demonstrate technical acceptability and then evaluated with respect to cost effectiveness.
Envenomation by the asp caterpillar (Megalopyge opercularis)

Background. The Asp Caterpillar, Megalopyge opercularis, is endemic to the southern United States and causes hundreds of human envenomations annually. Envenomation from the spines of the caterpillar causes severe pain, burning, swelling, nausea, abdominal distress, and headache. Despite the high prevalence of envenomations, little is known about the caterpillars, their geographical distribution, and the symptoms they engender. Methods. We collected and analyzed 188 case reports of asp caterpillar envenomations over a three-year period. Results. The geographical distribution of the caterpillars is confined to the southeast United States, largely in Texas, Louisiana, and Florida. Symptoms of envenomation vary, but typically include burning pain, swelling, nausea, and itching. The peak months of envenomation are July through November, with few cases reported at other times of year. Discussion. This study sheds light on the caterpillars' distribution and the range of symptoms caused in order to aid in diagnos...
Stereotactic Body Radiation Therapy (SBRT) for lung metastases.

The curative treatment of oligometastases with radiotherapy remains an area of active investigation. We hypothesise that treating oligometastases with SBRT can prolong life and potentially cure pat...
Image display and surgical visualization in interactive image-guided neurosurgery

Interactive image-guided surgery is the synchronous display of surgical position on medical images during surgery. We have developed a technique for the dynamic display of surgical position on up to three independent sets of tomographic images. Each of these image sets may be composed of square images of any size and are limited only by the size of the disk in the system. In addition to the raster images, a graphic display is provided for visualization of relative position and surgical trajectory, or real-time intraoperative images may be used. This device allows for improved 3-D surgical navigation and lesion margin definition.
Perception of aperiodicities in synthetically generated voices.

The purpose of this study was to investigate univariate relationships between perceived dysphonia and variation in pitch perturbation, amplitude perturbation, and additive noise. A time‐domain, pitch‐synchronous synthesis technique was used to generate sustained vowels varying in each of the three acoustic dimensions. A panel of trained listeners provided direct magnitude estimates of roughness in the case of the stimuli varying in pitch and amplitude perturbation, and breathiness in the case of the stimuli varying in additive noise. Very strong relationships were found between perceived roughness and either pitch or amplitude perturbation. However, unlike results reported previously for nonspeech stimuli, the subjective quality associated with pitch perturbation was quite different from that associated with amplitude perturbation. Results also showed that perceived roughness was affected not only by the amount of perturbation, but also by the degree of correlation between adjacent pitch or amplitude values. A strong relationship was found between perceived breathiness and signal‐to‐noise ratio. Contrary to previous findings, there was no interaction between signal‐to‐noise ratio and the amount of high‐frequency energy in the periodic component of the stimulus: Stimuli with similar signal‐to‐noise ratios received similar ratings, regardless of differences in the spectral slope of the periodic component.
West Nile Virus Genetic Diversity is Maintained during Transmission by Culex pipiens quinquefasciatus Mosquitoes

Due to error-prone replication, RNA viruses exist within hosts as a heterogeneous population of non-identical, but related viral variants. These populations may undergo bottlenecks during transmission that stochastically reduce variability leading to fitness declines. Such bottlenecks have been documented for several single-host RNA viruses, but their role in the population biology of obligate two-host viruses such as arthropod-borne viruses (arboviruses) in vivo is unclear, but of central importance in understanding arbovirus persistence and emergence. Therefore, we tracked the composition of West Nile virus (WNV; Flaviviridae, Flavivirus) populations during infection of the vector mosquito, Culex pipiens quinquefasciatus to determine whether WNV populations undergo bottlenecks during transmission by this host. Quantitative, qualitative and phylogenetic analyses of WNV sequences in mosquito midguts, hemolymph and saliva failed to document reductions in genetic diversity during mosquito infection. Further, migration analysis of individual viral variants revealed that while there was some evidence of compartmentalization, anatomical barriers do not impose genetic bottlenecks on WNV populations. Together, these data suggest that the complexity of WNV populations are not significantly diminished during the extrinsic incubation period of mosquitoes.
Variation in Pineal Melatonin Content during the Estrous Cycle of the Rat

AbstractPineal levels of melatonin exhibit a circadian rhythm in the rat. To determine if this rhythm varies during the estrous cycle, adult rats were sacrificed every 2 hr from 2000 hr (prior to lights off) until 0800 hr (2 hr after lights on) throughout each day of the 4-day estrous cycle. Pineal glands were assayed for melatonin by radioimmunoassay. A significant circadian rhythm in the pineal content of melatonin was evident each day of the cycle with peak levels exhibited during the dark phase. There were significant differences in titers of melatonin present at 0200, 0400, and 0600 hr between various stages of the cycle. In general, highest nighttime levels occurred during the evenings of metestrus and diestrus, with levels at a minimum on the evening of estrus. These data indicate that the circadian pineal melatonin rhythm is a function of estrous cycle stage in the rat, and, thus, important differences exist in the pineal biosynthetic dynamics of this species relative to those of seasonal breeders...
Potential Lessons from Public Health and Health Promotion for the Prevention of Child Abuse

SUMMARY Two successful public health efforts of the last third of the twentieth century-tobacco control and automobile injury controlare reviewed for relevance to the problem of child abuse. Potential lessons for child abuse prevention are identified and the following approaches are suggested: Investigate varied logic models or conceptual frameworks to identify new opportunities for effective intervention. Use a multi-disciplinary, multi-sector approach. Normalize desired behaviors and denormalize undesirable behaviors. Balance efficacy, feasibility, and cultural appropriateness. Develop strategies for effective policy advocacy based upon who benefits and who shoulders most of the burden.