cssi/SciSciGPT-SciSciNet huggingface dataset:
A rapid method for quantitating lymphocyte receptor capping: capping defect in AIDS patients.

Abstract Capping of concanavalin A (Con A) and anti-Leu-8 (L8) receptors on human peripheral blood mononuclear (PBM) membranes was studied utilizing fluorochromeconjugated ligands and flow cytometric analysis. Histogram profiles of fluorescent intensities consistently revealed a time-dependent decrease in numbers of brightly fluorescing events concurrent with an increase in numbers of dimly fluorescing events when capping occurs. Differences in fluorescence profiles were detectable by flow cytometric analysis as early as 5 min after capping conditions were initiated. A pronounced defect in receptor capping of PBM cells from AIDS patients was observed. This technique represents a rapid and reproducible means for detecting early changes in cell membrane receptor mobility.
Impedance methods for surface state electrons

A numerical procedure is given to determine the static charge configuration and electrical impedance of a circular pool of electrons on the surface of liquid helium. The response for an ac Corbino probe is obtained for arbitrary frequency. By fitting the results to audiofrequency capacitance-conductance data the local charge density and electric field configuration are found for arbitrary confining potentials. The locations of2D plasma modes are also in excellent agreement with those obtained numerically. Analytic forms are derived for uniform charge density configurations.
GLUCONEOGENIC AND BRANCH CHAIN AMINO ACID STUDIES IN HYPOPITUITARISM

Gluconeogenic amino acid and branch chain amino acid studies were performed on 8 growth hormone deficient patients without spontaneous hypoglycemia compared to constitutional short children. New information on alanine, glycine, glutamine and leucine was obtained comparing fasting versus 30 minute response to S.C. Glucagon 30 ug/kg. Comparable fasting and gluconeogenic hypoaminoacidemic responses to Glucagon occurred in all study groups, i.e., controls, pre-hGH therapy, post-hGH therapy, Anavar, and hGH plus Anavar. However, plasma branch chain amino acid leucine delta (Δ) absolute reduction in response to Glucagon was enhanced in hGH deficient children on Anavar alone or in combination with hGH. Plasma leucine absolute change (Δ) pre-hGH -18±4uM S.E.M., on Anavar −27±4 S.E.M. (p <0.05) and hGH plus Anavar −34±3 S.E.M. (<0.01). Thus branch chain but not gluconeogenic amino acid was affected by the anabolic nature of Anavar and growth hormone. Lower fasting glucose and insulin values with blunted responses to Glucagon were noted in hGH deficient children. Asymptomatic hGH deficient patients failed to show fasting hypoalaninemia or abnormal (Δ) response to Glucagon, suggesting that hGH deficiency alone does not lead to gluconeogenic substrate-limited disorder. Whereas an additional ketotic hypoglycemic patient studied with both hGH and ACTH deficiency did show blunted hypoalaninemic response to Glucagon, i.e., Δ-10μM pre-therapy; Δ-20μM on hGH and Δ-130μM on cortisone. hGH support by the National Hormone and Pituitary Program.
Analysis of thiolester bond cleavage-dependent conformational changes in binary α2-macroglobulin-proteinase complexes

Abstract The structures of the two proteinase-binding sites in human α 2 -macroglobulin (α 2 M) were probed by treatment of α 2 M with the serine proteinases thrombin and plasmin. Each proteinase forms an equimolar complex with α 2 M (a binary α 2 M-proteinase complex) which results in the activation and cleavage of two internal thiolester bonds in α 2 M. Binary α 2 M-proteinase complexes demonstrated an incomplete conformational change as determined by nondenaturing polyacrylamide gel electrophoresis and incomplete receptor recognition site exposure as determined by in vivo plasma elimination studies. Treatment of binary α 2 M-proteinase complexes with CH 3 NH 2 , trypsin, or elastase resulted in cleavage of an additional one or two thiolester bonds in α 2 M and complete receptor recognition site exposure, demonstrating that a limited conformational change had occurred. Treatment of the α 2 M-thrombin complex with elastase resulted in the incorporation of approximately 0.5 mol proteinase/mol α 2 M and completion of the conformational change in the complex. Similar treatment of the α 2 M-plasmin complex resulted in the incorporation of less than 0.1 mol proteinase/mol α 2 M. Unlike the α 2 M-thrombin complex, the α 2 M-plasmin complex did not undergo a complete conformational change following treatment with CH 3 NH 2 or trypsin. Incubation of this complex with elastase resulted in proteolysis of the kringle 1–4 region of the α 2 M-bound plasmin heavy chain, and following this treatment the α 2 M-plasmin complex underwent a complete conformational change. The results of this investigation demonstrate that binary α 2 M-proteinase complexes retain a relatively intact proteinase-binding site. In the case of the α 2 M-plasmin complex, however, the heavy chain of α 2 M-bound plasmin protrudes from the proteinase-binding site and prevents a complete conformational change in the complex despite additional thiolester bond cleavage.
Nonmethane hydrocarbons and ozone in three rural southeast United States national parks: A model sensitivity analysis and comparison to measurements

[1] A detailed modeling analysis is conducted focusing on nonmethane hydrocarbons and ozone in three southeast United States national parks for a 15-day time period (14–29 July 1995) characterized by high O3 surface concentrations. The three national parks are Smoky Mountains National Park (GRSM), Mammoth Cave National Park (MACA), and Shenandoah National Park (SHEN), Big Meadows. A base emission scenario and eight variant predictions are analyzed, and predictions are compared with data observed at the three locations for the same time period. Model-predicted concentrations are higher than observed values for O3 (with a cutoff of 40 ppbv) by 3.0% at GRSM, 19.1% at MACA, and 9.0% at SHEN (mean normalized bias error). They are very similar to observations for overall mean ozone concentrations at GRSM and SHEN. They generally agree (the same order of magnitude) with observed values for lumped paraffin compounds but are an order of magnitude lower for other species (isoprene, ethene, surrogate olefin, surrogate toluene, and surrogate xylene). Model sensitivity analyses here indicate that each location differs in terms of volatile organic compound (VOC) capacity to produce O3, but a maximum VOC capacity point (MVCP) exists at all locations that changes the influence of VOCs on O3 from net production to production suppression. Analysis of individual model processes shows that more than 50% of daytime O3 concentrations at the high-elevation rural locations (GRSM and SHEN) are transported from other areas; local chemistry is the second largest O3 contributor. At the low-elevation location (MACA), about 80% of daytime O3 is produced by local chemistry and 20% is transported from other areas. Local emissions (67–95%) are predominantly responsible for VOCs at all locations, the rest coming from transport. Chemistry processes are responsible for about 50% removal of VOCs for all locations; less than 10% are lost to surface deposition and the rest are exported to other areas. Metrics, such as VOC potential for O3 production (VPOP), which links the chemistry processes of both O3 and VOCs and MVCP, are devised to measure the different characteristics of O3 production and VOCs. The values of the defined metrics are mapped for the entire modeling domain. Implications of this model exercise in understanding O3 production are analyzed and discussed. Even though this study was focused on three United States national parks, the research results and conclusions may be applicable to other or to similar rural environments in the southeast United States.
Managing legal liability of the Net: a ten step guide for IT managers

The exploding use of the Internet for everyday communication is bringing new threats to companies – revelation of trade secrets, discrimination, harassment, copyright infringement, negligence, libel, and slander, etc. The threat to companies is real. Lawyers can seek information in electronic records, including e‐mail, on litigation or criminal cases. This paper gives an overview of where the risks lie, and what the IT managers should do to minimize the risk.
Strategic management and economics

This essay examines the relationship between strategic management and economics. It introduces the special issue on this same topic by providing a guide to the eight papers contained in the special issue, and it offers the guest editors viewpoints on the contributions of each discipline to the other. The essay notes the major contribution from economics has been primarily from the industrial organization literature, with promises of important gains to be made from the ‘new’ economics as it breaks away from the neoclassical theory of the firm. Contributions from strategic management to economics are noted. Areas for further research utilizing the relationship between strategic management and economics are also indicated.
Radiative transport in a planar medium exposed to azimuthally unsymmetric incident radiation

An analytical solution is developed for the radiation field engendered by illuminating an absorbing/anisotropically scattering planar medium with an azimuthally unsymmetric incident flux. The boundaries of the medium are allowed to possess both specular and diffuse reflection characteristics. The problem is mathematically reduced to solving a system of azimuthally independent equations which may be analyzed by many existing techniques. A solution scheme is formulated in terms of singular eigenfunctions and solved using a modified FN method. Computations are performed for the azimuthally symmetric case of irradiation by parallel rays at oblique incidence. Several different phase functions are considered and results are presented for the discrete eigenvalues, the heat flux distributions within the medium, the reflectance and transmittance of the slab and the angular distribution of the intensities at the boundaries.
Maximum tearing energy computation for 3D rubber fracture

Abstract This paper presents a finite element procedure for computing tearing energy for any arbitrarily shaped 3D crack front in rubber solids using the virtual crack extension method. The magnitude and direction of maximum tearing energy can be evaluated from the specified virtual crack extensions in three dimensions defined by spherical coordinates for any type of crack front. This finite element procedure was applied to a double pure shear fracture specimen. The results obtained for tearing energy are in good agreement with those calculated with the J -integral as well as with the experimental data. It is shown that a sinusoidal tearing energy distribution occurs within the crack front normal plane for a double pure shear fracture specimen.
Atomic beam preparation for hydrogen maser operation with unpolarized atoms

The conventional atomic beam preparation technique for hydrogen maser operation consists of a six pole magnetic field focussing in combination with adiabatically changing magnetic fields in the transition region between focusser and maser cavity, which results in a state selected, polarized ensemble of hydrogen atoms. Hydrogen maser operation with state selected, but unpolarized atoms has the advantage to reduce considerably the sensitivity of hydrogen maser frequency on coherently excited, low frequency,ΔmF=±1 Zeeman transitions. The influence of the magnetic field pattern in the transition region on the energy level population probabilities for the focussed hydrogen beam has been analysed. Atomic beam preparation techniques using non-adiabatically changing magnetic field configurations in the transition region are described. The dependence of hydrogen maser oscillation on the energy level population within the atomic beam is theoretically investigated and the results are used for the analysis of the experimentally achieved atomic beam populations. It has been shown that a pulsed magnetic spin guidance field in the transition region, which switches between adiabatically changing magnetic field configurations and a sudden magnetic field reversal, results in an ensemble of hydrogen atoms with vanishing time averaged polarization, which does not deteriorate the conventionally achieved maser oscillation amplitude.
THOMAS, GARY. How to Do Your Case Study: A Guide for Students and Researchers. Thousand Oaks, CA: Sage Publications, 2011. Pp. xi, 231. $45.00, paper. ISBN 978–0–85702–563–0.

The article review the book "How to Do Your Case Study: A Guide for Students and Researchers" by Gary Thomas.
The Benefit of Adjuvant Chemotherapy in Elderly Patients with Stage III Colorectal Cancer is Independent of Age and Comorbidity

Objectives To determine the combined effect of age and comorbidity on receipt of chemotherapy and its impact on survival in elderly patients with stage III colorectal cancer (CRC).
Implications of the Colonic Deposition of Free Hemoglobin-α Chain: A Previously Unknown Tissue By-product in Inflammatory Bowel Disease

Purpose We analyzed inflamed mucosal/submucosal layers of ulcerative colitis (UC=63) and Crohn’s colitis (CC=50) and unexpectedly we unveiled a pool of free-hemoglobin-alpha (Hb-α) chain. Patients with colitides have increased ROS, DNA-oxidation products, free-iron in mucosa, in pre-neoplastic, and in colitis-cancers and increased risks of developing colorectal-cancer (CRC). All IBD-related-CRC lesions are found in segments with colitis. Linking this information we investigated whether free-Hb-α is key transformational stepping that increases colitis-related-CRC vulnerability.
Experimental approaches to chronic wounds

The pathogenesis of most chronic wounds is unknown. In this report, we summarize several areas of investigation which appear ready for further progress and which were discussed at a recent National Institutes of Health workshop on this subject. Of note were presentations of research on the role of fibrosis in wound healing, interaction of cytokines, hypoxia, extracellular matrix formation, keratinocyte migration, and involvement of proteases and neuropeptides in chronic wounds.
Lessons from crisis recovery in schools: how hurricanes impacted schools, families and the community

This article examines school and school district-level efforts to reopen schools after significant damage from hurricanes. Through an empirical, qualitative research design, four themes emerged as critical to the hurricane recovery process: the importance of communication, resolving tension, coordinating with other services and learning from the past. School administrators must proactively plan for catastrophic events and balance the need for open communication within and outside the school district; to resolve tensions; and to coordinate with other public and private efforts to restore the community. Finally, they should use each experience as a learning opportunity.
Conditional mesenchymal disruption of pkd1 results in osteopenia and polycystic kidney disease.

Conditional deletion of Pkd1 in osteoblasts using either Osteocalcin(Oc)-Cre or Dmp1-Cre results in defective osteoblast-mediated postnatal bone formation and osteopenia. Pkd1 is also expressed in undifferentiated mesenchyme that gives rise to the osteoblast lineage. To examine the effects of Pkd1 on prenatal osteoblast development, we crossed Pkd1flox/flox and Col1a1(3.6)-Cre mice, which has been used to achieve selective inactivation of Pkd1 earlier in the osteoblast lineage. Control Pkd1flox/flox and Pkd1flox/+, heterozygous Col1a1(3.6)-Cre;Pkd1flox/+ and Pkd1flox/null, and homozygous Col1a1(3.6)-Cre;Pkd1flox/flox and Col1a1(3.6)-Cre;Pkd1flox/null mice were analyzed at ages ranging from E14.5 to 8-weeks-old. Newborn Col1a1(3.6)-Cre;Pkd1flox/null mice exhibited defective skeletogenesis in association with a greater reduction in Pkd1 expression in bone. Conditional Col1a1(3.6)-Cre;Pkd1flox/+ and Col1a1(3.6)-Cre;Pkd1flox/flox mice displayed a gene dose-dependent decrease in bone formation and increase in marrow fat at 6 weeks of age. Bone marrow stromal cell and primary osteoblast cultures from homozygous Col1a1(3.6)-Cre;Pkd1flox/flox mice showed increased proliferation, impaired osteoblast development and enhanced adipogenesis ex vivo. Unexpectedly, we found evidence for Col1a1(3.6)-Cre mediated deletion of Pkd1 in extraskeletal tissues in Col1a1(3.6)-Cre;Pkd1flox/flox mice. Deletion of Pkd1 in mesenchymal precursors resulted in pancreatic and renal, but not hepatic, cyst formation. The non-lethality of Col1a1(3.6)-Cre;Pkd1flox/flox mice establishes a new model to study abnormalities in bone development and cyst formation in pancreas and kidney caused by Pkd1 gene inactivation.
Discharge inception in high-voltage three-electrode systems

A criterion is developed for calculating the discharge inception voltage in three-electrode systems, i.e. inception voltage from free particles existing in a uniform field gap in air. The criterion is a formulation of the conditions necessary for a self-sustained corona discharge. These conditions are identical to those of the uniform field. As the individual processes and events involved in this formulation are field dependent, the electric field is calculated using the charge simulation technique and the method of images to account for the distortion of the applied uniform field by the particle as well as the space charge developed in the gap. The calculated field values normalised to the applied-field value agreed very well with the analytical solution for spherical particles. Also, the calculated inception voltages agreed well with those measured experimentally for spherical and spheroidal particles.
Selective Exposure and Reinforcement of Attitudes and Partisanship Before a Presidential Election

Right before the 2008 U.S. presidential election, this 2-session online field study examined consequences of selective exposure to political messages on accessibility of attitudes and of partisanship. In the first session, participants indicated attitudes toward political issues and their partisanship, which allowed measuring accessibility of attitudes and of partisanship. In the second session, participants browsed articles. Four issues were covered by 8 articles, with 2 articles featuring opposing perspectives. Selective exposure was unobtrusively logged. Finally, participants completed measures for attitudes and partisanship again. Selective exposure to attitude-consistent articles was linked to greater attitude accessibility. The indirect impact of selective exposure on partisanship accessibility through attitude accessibility was significant.
Lessons from the National Alliance of Business Compact Project: Business and Public Education Reform

This paper reports on some of the key outcomes of the National Alliance of Business's Compact Project, a 12-city demonstration project intended to establish collaborations among businesses, public schools, and government. Factors related to problem recognition, definition and crystallization, the macroenvironmental context, and the emergence of a systemic orientation toward school improvement are associated with more and less successful outcomes. Reframing processes pervade development of a vision about education, the ways in which institutions relate to each other, as well as their orientation toward solving educational problems. More successful cities in the project adopted a systemic approach rather than more limited programmatic efforts to change the schools.
On the spiral growth of Pb-Sn eutectic alloys

Abstract Directionally solidified Pb-Sn eutectic alloys have been observed to display four different crystallographic relationships. The present study determined that only one of these crystallographies exhibits the spiral growth phenomenon. The rate of spiralling was shown to increase strongly with solidification rate; its dependence upon temperature gradient was not reproducible, but it was found that the spiral rate did not decrease with increasing gradient as previous investigators had postulated.
Noise trading and prime and score premiums

Abstract This paper documents that a common element drives the time-series variation of the premium pricing of Primes and Scores. I argue that this common element is noise trading. The noise trading model of Delong, Shleifer, Summers and Waldmann (1990) predicts that returns on assets that are predominantly traded by noise traders will be correlated, since the misperceptions of noise traders are cross-sectionally correlated. Consistent with the noise trading hypothesis, changes in the average premium of Primes and Scores, which are predominantly traded by individual investors, are correlated with both changes in average discounts of closed-end funds and small firms returns. These empirical facts provide additional evidence that noise traders can affect security prices.
ATP Hydrolysis Stimulates Large Length Fluctuations in Single Actin Filaments

Polymerization dynamics of single actin filaments is investigated theoretically using a stochastic model that takes into account the hydrolysis of ATP-actin subunits, the geometry of actin filament tips, and the lateral interactions between the monomers as well as the processes at both ends of the polymer. Exact analytical expressions are obtained for the mean growth velocity, for the dispersion in the length fluctuations, and the nucleotide composition of the actin filaments. It is found that the ATP hydrolysis has a strong effect on dynamic properties of single actin filaments. At high concentrations of free actin monomers, the mean size of the unhydrolyzed ATP-cap is very large, and the dynamics is governed by association/dissociation of ATP-actin subunits. However, at low concentrations the size of the cap becomes finite, and the dissociation of ADP-actin subunits makes a significant contribution to overall dynamics. Actin filament length fluctuations reach a sharp maximum at the boundary between two dynamic regimes, and this boundary is always larger than the critical concentration for the actin filament's growth at the barbed end, assuming the sequential release of phosphate. Random and sequential mechanisms of hydrolysis are compared, and it is found that they predict qualitatively similar dynamic properties at low and high concentrations of free actin monomers with some deviations near the critical concentration. The possibility of attachment and detachment of oligomers in actin filament's growth is also discussed. Our theoretical approach is successfully applied to analyze the latest experiments on the growth and length fluctuations of individual actin filaments.
Microbial infection and inflammation in the development of chronic lung disease of prematurity

Bronchopulmonary dysplasia or chronic lung disease of prematurity is a prolonged respiratory failure with multifactorial etiology in very low birth-weight neonates. This review summarizes current knowledge about the molecular mechanisms of different infections and inflammatory responses that are involved in the development of chronic lung disease of prematurity.
The Manhattan Project

The Manhattan Project was the United States Army’s program to develop and deploy nuclear weapons during World War II. In these devices, which are known popularly as ‘atomic bombs’, energy is released not by a chemical explosion but by the much more violent process of fission of nuclei of heavy elements via a neutron-mediated chain-reaction. Three years after taking on this project in mid-1942, the Army’s Manhattan Engineer District produced three nuclear bombs of two different designs. Two of these devices were fueled with the 239 isotope of the synthetic element plutonium, while the third employed the rare 235 isotope of uranium. One of the plutonium devices, code-named Trinity, was detonated in a test in southern New Mexico on 16 July 1945; this was the world’s first nuclear explosion. Three weeks later, on 6 August, the uranium bomb, Little Boy, was dropped on the Japanese city of Hiroshima. On 9 August the second plutonium device, Fat Man, was dropped on Nagasaki. Together, the two bombings killed over 100 000 people and were at least partially responsible for the Japanese government’s 14 August decision to surrender. This article surveys, at an undergraduate level, the science and history of the Manhattan Project.
Virtual excitation type surface polaritons on anisotropic media

Abstract We discuss the nature of a new type of surface polariton which occurs on anisotropic media, involving a photon coupled to a surface virtual excitation. Dispersion curves are calculated for α-quartz, where both real excitation type and virtual excitation type surface polaritons are predicted. The dispersion curves for virtual excitation surface polaritons are found to remain at small wavevector, and the endpoints of the dispersion curves terminate on the bulk polariton dispersion curves in the two media. The virtual excitation surface polaritons which occur on gyromagnetic and gyrodielectric media are also noted.
Stability of vertical miscible displacements with developing density and viscosity gradients

Viscous fingering and gravity tonguing are the consequences of an unstable miscible displacement. Chang and Slattery (1986) performed a linear stability analysis for a miscible displacement considering only the effect of viscosity. Here the effect of gravity is included as well for either a step change or a graduated change in concentration at the injection face during a downward, vertical displacement. If both the mobility ratio and the density ratio are favorable (the viscosity of the displacing fluid is greater than the viscosity of the displaced fluid and, for a downward vertical displacement, the density of the displacing fluid is less than the density of the displaced fluid), the displacement will be stable. If either the mobility ratio or the density ratio is unfavorable, instabilities can form at the injection boundary as the result of infinitesimal perturbations. But if the concentration is changed sufficiently slowly with time at the entrance to the system, the displacement can be stabilized, even if both the mobility ratio and the density ratio are unfavorable. A displacement is more likely to be stable as the aspect ratio (ratio of thickness to width, which is assumed to be less than one) is increased. Commonly the laboratory tests supporting a field trial use nearly the same fluids, porous media, and displacement rates as the field trial they are intended to support. For the laboratory test, the aspect ratio may be the order of one; for the field trial, it may be two orders of magnitude smaller. This means that a laboratory test could indicate that a displacement was stable, while an unstable displacement may be observed in the field.
Experimental Study on the Stabilization of the No-Motion State in the Rayleigh-Benard Convection Problem

We demonstrate experimentally that through the use of proportional-differential control, it is possible to stabilize the no-motion state of a fluid layer heated from below, cooled from above, and confined in an upright, circular cylinder (the Rayleigh-Benard problem). An array of 24 independently controlled heaters (thermal actuators), microfabricated on a silicon wafer, constitutes the bottom boundary of the test cell. A cooling system maintains the top boundary at a constant temperature. Silicon diodes located at the mid-height of the cell, above the actuators, measure the fluid's temperature. The multi-input, multi-output controller adjusts the heaters' power in proportion to the deviation of the fluid's temperatures, as recorded by the diodes, from preset values associated with the no-motion, conductive state. First, a set of experiments was conducted in the absence of a controller to determine the uncontrolled, reference state. Advantage is taken of the linear dependence of the mid-height temperature on the power input in the no-motion state. The preset temperatures are determined by extrapolating the mid-height temperatures to the desired input power values. A proportional controller is then engaged. We show that as the controller's gain increases so does the critical Rayleigh number for the onset of convection. The proportional controller allows us to increase the critical Rayleigh number by as much as a factor of 1.4. When the controller's gain is larger than a critical value, the system becomes time-wise oscillatory (Hopf bifurcation) and the controller's performance deteriorates. The oscillatory convection can be significantly damped out by engaging a proportional-differential (PD) controller. The PD controller allows us to further increase the critical Rayleigh number for the onset of convection to as much as a factor or 1.7 compared to the uncontrolled case. Further increases in the critical Rayleigh number were not possible due to the actuators' saturation. We also compared the supercritical flow patterns at the mid-height of the test cell in the presence of the controller with the flow patterns in the absence of a controller. The proportional controller modified the flow pattern from a single convective cell with ascending fluid in one half of the cell and descending in the other half, to fluid ascending at the center of the cell and descending at near the lateral wall. Our work represents an improvement over previous experimental investigations on the stabilization of Rayleigh-Benard convection in which the critical Rayleigh number was increased by only a factor of 1.2. Almost uniform temperature distribution at the mid-height is obtained through the combined action of proportional and derivative controllers. The Rayleigh-Benard convection is suppressed under conditions when, in the absence of a controller, flow would persist.Copyright © 2006 by ASME
Does Abdominal Breathing Affect Regional Gas Exchange

Does the use of the abdomen during inspiration alter gas exchange to the bases of the lungs? Most previous investigators have concluded that this technique does not affect regional ventilation. However, if gas concentrations are used as an index of gas exchange, if the subject has normal lungs, is seated and performs the maneuver with the assistance of a physiotherapist, the answer is an unequivocal yes. This study does not pinpoint the exact mechanism by which this alteration is accomplished, but suggests that changes in thoracoabdominal shape influence regional blood flow. It does not indicate whether this effect is beneficial or detrimental. Whether the large number of patients with obstructive lung disease who attempt this maneuver in an unsupervised manner alter gas exchange in any way is uncertain. However, the data do suggest that some patients might be affecting their lung function, and we should learn more about the precise mechanisms.
PARTICIPATION MOTIVES AND LEARNING OUTCOMES AMONG OLDER LEARNERS

Although older students are participating in formal educational programs at increasingly higher rates, few studies have examined learning outcomes or the relationship between motivational factors for participation and outcomes. This research project surveyed 560 older students attending Elderhostel programs. The purpose of the study was to examine self‐reported learning outcomes and study the predictive relationships between reasons for participation and outcomes. Students reported moderate levels of growth on two outcomes factors: humanities/critical thinking and human relations/personal development. Multiple regression analysis revealed that the best predictors of learning outcomes among older participants in Elderhostel programs were setting clear goals for learning and the specific nature of the courses and institutions attended.
Cyclic nucleotide phosphodiesterase activities of pig coronary arteries.

Abstract Most (85% or more) of the cyclic nucleotide phosphodiesterase (3′:5′-cyclic-AMP 5′-nucleotidohydrolase, EC 3.1.4.17) activity of pig coronary arteries was found in the 40 000 × g supernatant fraction of homogenates of the intima plus media layer. Chromatography of the soluble fraction of this layer on DEAE-cellulose resolved two phosphodiesterase activities and a heat stable, non-dializable activator. Peak I activity had apparent K m values of 2–4 μM for cyclic GMP and 40–100 μM for cyclic AMP. Peak II activity was relatively specific for cyclic AMP and exhibited apparent negatively cooperative behavior. Peak I but not peak II activity could be stimulated 3–8-fold by the addition of the boiled activator fraction or a boiled crude supernatant fraction. Cyclic AMP hydrolysis by peak I or peak II was more rapid in the presence of Mn 2+ than Mg 2+ , but the latter promoted hydrolysis of cyclic GMP by peak I more effectively than did Mn 2+ in the presence of activator. In the absence of added metals, ethylene bis(oxyethylenenitrilo)tetra-acetic acid (EGTA) and EDTA both inhibited hydrolysis of cyclic AMP and cyclic GMP by phosphodiesterase activities in the supernatant fraction and in peak I, but EDTA produced more complete inhibition at lower concentrations than did EGTA. Imidazole (1 μM to 10 mM) had virtually no effect on the hydrolysis of cyclic AMP or cyclic GMP catalyzed by either of the two separated peaks or by total phosphodiesterase activities in crude supernatant or particulate fractions.
Extremozymes: Expanding the Limits of Biocatalysis

The study of enzymes isolated from organisms inhabiting unconventional ecosystems has led to the realization that biocatalysis need not be constrained to mild conditions and can be considered at pH's, temperatures, pressures, ionic and solvent environments long thought to be destructive to biomolecules. Parallel to this, it has been demonstrated that even conventional enzymes will catalyze reactions in solvents other than water. However, the intrinsic basis for biological function under extreme conditions is only starting to be addressed, as are associated applications. This was the focus of a recent NSF/NIST-sponsored workshop on extremozymes. Given the information acquired from the study of extremozymes, modification of enzymes to improve their ranges of stability and activity remains a possibility. Ultimately, by expanding the range of conditions suitable for enzyme function, new opportunities to use biocatalysis will be created.
Pink Shrimp Feeding Experiments with Wheat Bran1

Other investigators have suggested that detritus enriched by the micro-organisms that degrade it is a major component of the natural diet of penaeid shrimp. This paper describes pink shrimp (Penaeus duorarum) feeding experiments in earthen ponds and concrete tanks, with wheat bran used to produce an artificial detritus food for the shrimp. Wheat bran and other foods are compared, and the effects of food type, feeding methods, and certain aspects of water quality on growth, survival and yield of pink shrimp are evaluated. The artificial detritus method of feeding in the culture of shrimp is much simpler than the feeding of pelleted or other diets directly to shrimp, since the former does not depend upon monitoring of growth rates and population densities to determine feeding rates. Wheat bran is added to unaerated tanks or ponds at constant rates that do not cause oxygen depletion. We have added wheat bran to ponds at daily rates up to 35 kg per ha without causing obvious problems. With wheat bran feeding, it seems possible to rear postlarval pink shrimp in ponds or tanks to about 4 g (live bait size) in 3 months and at stocking densities as high as 100,000 per ha, and with survival as high as 90%. Our investigations of the artificial detritus feeding method will continue with the goal of developing methods for producing food shrimp profitably.
The calculation of Sobolev's ϕ function of radiative transfer via numerical inversion of Laplace transforms

The linear integral equation of convolution type of Sobolev's function ϕ is solved computationally using a new method for the numerical inversion of Laplace transforms.
An Unusual Form of Vitamin D-Dependent Rickets in a Child: Alopecia and Marked End-Organ Hyposensitivity to Biologically Active Vitamin D

A 12-yr-old female patient with an unusual form of vitamin D dependency and alopecia is described. She was a product of consanguineous mating and developed signs and symptoms suggesting vitamin D dependency early in life. Neither 150 μg/day (6 μg/kg·day) 1α-hydroxyvitamin D3) nor 5 μg/day (0.2 μg/kg·day) 1,25-dihydroxyvitamin D3 proved to have an effect on her abnormal serum chemistry. Seven million international units per day (about 2 × 105 IU/kg·day) of native vitamin D restored her serum chemistry to normal and brought about marked improvement on skeletal radiographs, when her serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and 24,25-di-hydroxyvitamin D were 4250, 4.8, and 35 ng/ml, respectively. Even with the high serum levels of vitamin D metabolites, her intestinal 47Ca absorption rate remained in the lower normal range and urinary calcium excretion was decidedly low. Association of hypoparathyroidism was ruled out. These results suggest that this patient has extreme end-organ (intestine) hypose...
Do Poverty Attitudes of Social Service Agency Directors Influence Organizational Behavior

This article explores why people are poor and on welfare, according to social service agency directors who administer programs that serve current and former welfare recipients. Based on data from 2...
Numerical Modeling of Extrusion Welding in Magnesium Alloys

Solid-state welding takes place during the extrusion of hollow shapes and tubes made from selected metals such as aluminum and magnesium and their alloys. DEFORMTM is one of the most frequently used FEM software packages to analyze the metal flow in deformation processes. However, it has some limitations while applied to study the extrusion welding. The 2D and 3D versions of DEFORMTM cannot determine if extrusion welding takes place in a port-hole die. This limitation is a result of a lack of ability to transfer the localized deformation conditions to a judgment about a good or poor weld. In this work, a new modeling method has been proposed to obtain the localized information at the extrusion welding seam. A so-called pressure plate was virtually inserted in the position of the extrusion welding seam, which plays a role of a sensor and has recorded all the information at the given seam during the entire extrusion process. Analytical methods have been utilized to study the data collected from this sensor to evaluate the probability of the formation of the sound extrusion welding seam. The generated results have been used to verify Plata & Piwnik extrusion welding criterion and can be implemented into existing extrusion models to achieve better prediction of weld integrity.
Hepatic bile pigment excretion and erythrocyte turnover in various species.

Summary Endogenous bile pigment excretory rates have now been recorded in fifteen species, and the following review briefly compares the excretion per unit of body weight in animals of varying sizes, attempts to determine if any correlation exists between bile flow and endogenous pigment excretion and discusses bile pigment excretion in relation to mean erythrocyte survival time and metabolic rate. Graphs and one table illustrating pigment metabolism and erythrocyte replacement are presented. Differences between animals excreting primarily biliverdin as opposed to bilirubin are discussed, with special attention being given throughout the article to mammals and their individual differences. Accepted theory concludes that the rate of endogenous bile pigment excretion is primarily dependent upon hemoglobin cata-bolism. However, further studies will be necessary to clarify basic physiological mechanisms in order to substantiate any theory concerning the correlation of erythrocyte turnover with metabolic rates.
Using fixed-time schedules to maintain behavior: a preliminary investigation.

The purpose of this study was to evaluate the potential of fixed-time (FT) schedules to maintain behavior. Two children who had been diagnosed with autism were taught a functional task. Subsequently, three different FT schedules (i.e., yoked, thin, dense) were compared to determine their capacity to maintain task responding. Results suggested that FT schedules may be used to maintain previously acquired behavior.
Nanotribology of carbon nanotubes

Carbon nanotubes (CNTs) have remarkable mechanical and electrical properties which make them attractive for a large number of applications. Attempts have been made to develop reinforced composites, super-strong fibers and sheets, nanoprobes, chemical and biological sensors, nanoscale electromechanical devices and molecular electronics. Nanotube arrays are being developed for field-emitter-based screens and thermal management. The mechanical strength of many of these devices critically relies on the nanotribology and nanomechanics of CNTs. Various investigations of adhesion, friction, wear and mechanics of MWNTs, SWNTs and MWNT arrays have been carried out. This paper provides an overview.
Elephant in the Break Room: The use of Modified Operational Sequence Diagrams for the Determination of Zoo Exhibit Inefficiencies

Although human factors has been applied to situations involving animals, it has not been formally used in zoo exhibit design. Zoo exhibits with their varied, and possibly conflicting, goals of three distinct user groups present a unique opportunity to apply human factors to improve the design process. Treating zoo staff, visitors, and animals as co-workers, each with input into the exhibit system, allows the design process to be optimized in order to maximize efficient use of time and better meet the needs of all users. Ideally, well designed exhibits will maximize animal welfare while increasing the efficiency and safety of zoo staff. Additionally, exhibits should enhance the visitor experience, allowing them to connect with the exhibit and learn from it, ideally by viewing species-typical behavior. The current paper uses a novel approach, a modified Operational Sequence Diagrams, to examine the needs of the zoo system. This methodology is used because of its flexibility and ease of understanding for zoo...
Challenges of the information age: the impact of false discovery on pathway identification

Pathways with members that have known relevance to a disease are used to support hypotheses generated from analyses of gene expression and proteomic studies. Using cancer as an example, the pitfalls of searching pathways databases as support for genes and proteins that could represent false discoveries are explored. The frequency with which networks could be generated from 100 instances each of randomly selected five and ten genes sets as input to MetaCore, a commercial pathways database, was measured. A PubMed search enumerated cancer-related literature published for any gene in the networks. Using three, two, and one maximum intervening step between input genes to populate the network, networks were generated with frequencies of 97%, 77%, and 7% using ten gene sets and 73%, 27%, and 1% using five gene sets. PubMed reported an average of 4225 cancer-related articles per network gene. This can be attributed to the richly populated pathways databases and the interest in the molecular basis of cancer. As information sources become enriched, they are more likely to generate plausible mechanisms for false discoveries.
Removal of Phytate from Great Northern Beans (Phaseolus vulgaris L.) and Its Combined Density Fraction

The effect of pH on the dissociation of phytate complexes and subsequent removal of phytate from Great Northern bean (GNB) flour and its combined density fraction (CDF) was investigated. The largest amount of phytate removed was from GNB flour and CDF dispersions adjusted to pH 7.0 during dialysis. Dialyzed, unadjusted GNB flour and CDF respectively contained 55.4% and 59% of phytate in water-soluble form. The results indicate that phytic acid is present in GNB as a water soluble salt with a M.W. less than 1,000 daltons, water soluble complex with M.W. more than 1,000 daltons, and water insoluble complex. The presence of phytate in the CDF did not affect in vitro digestibility of CDF proteins.
An antenna mismatch immuned CMOS power amplifier

A 2.4 GHz reconfigurable CMOS power amplifier to minimize antenna mismatch effects is presented. The PA is implemented by using a 0.18-μm RF CMOS process, and the supply voltage is 3.3 V. The proposed PA is compared to a conventional PA with a fixed matching network. By utilizing the proposed reconfigurable matching network, both the efficiency and the output power are improved under an antenna mismatch condition while satisfying the linearity specifications. For example, the maximum linear power and PAE are increased from 11.1-dBm to 16.1-dBm and from 8.1% to 19% at a Γ=0.3ζ45 condition, respectively. To our knowledge, this is the first fully-integrated CMOS PA with a reconfigurable matching network that improves the robustness to the antenna mismatch.
Mobile Networks: Visualizing the Global Refugee Regime

This article identifies conceptual issues surrounding the visualization of refugee movement in relation to state borders. It argues that social-network-analysis software provides a tool for the creation of visualizations of human movement that are removed from geolocation. Such a method disassociates forced migration from preconceived notions about the importance of geographical proximity and the fixity of state borders. This article provides some brief examples of ways that these methods might be utilized to graph and visualize aspects of the global refugee regime. The global-scale, transnational conceptualization and new visualizations show networks of movement centered on new inter-state communities and highlights the role of non-state actors.
SEQUENTIAL SENSITIVITY ANALYSIS FOR SAME-DIFFERENT TESTS : SOME FURTHER INSIGHTS

A Sequential Sensitivity Analysis was performed for same–different tests using low-concentration threshold NaCl solutions versus purified water. The order of favorability for the sequence pairs (W-S, W-W, S-S, S-W) was different from the order obtained in previous studies (W-S, S-W, W-W, S-W). In the current study, the order depended on the judge's ability to recognize perceptual changes; this could be said to involve a decision rule or cognitive strategy that used a τ criterion. In previous studies, the orders depended on the judges’ ability to recognize individual stimuli; this could be said to involve a decision rule that used a β criterion. Further insights into the interpretation of these orders were discussed. PRACTICAL APPLICATIONS Sequential Sensitivity Analysis provides a simple first-order ordinal model for predicting the sensitivity of difference tests, once suitable preliminary data have been obtained. This article provides new data that allow a fuller understanding of the sensory mechanisms involved in the model, which will improve the validity of predictions being made regarding difference test sensitivity.
The Factor Tau in the Black-Litterman Model

This paper considers the factor tau (τ) in the Black-Litterman model. τ is one of the more confusing aspects of the model, as authors provide contradictory information regarding its use and calibration. We will consider the origin of the mixed-estimation model used in the Black-Litterman Model so that we can develop a richer understanding of τ and its place in the model. We will discuss the various models which use the name Black-Litterman and how they do or do not use τ. Finally, we will show several ways to calibrate τ when using the canonical Black-Litterman model.