cssi/SciSciGPT-SciSciNet huggingface dataset:
Synthesis and photopolymerization of low shrinkage methacrylate monomers containing bulky substituent groups

Summary Objectives This study was conducted to determine whether novel photopolymerizable formulations based on dimethacrylate monomers with bulky substituent groups could provide low polymerization shrinkage without sacrifice to degree of conversion, and mechanical properties of the polymers. Methods Relatively high molecular weight dimethacrylate monomers were prepared from rigid bisphenol A core groups. Photopolymerization kinetics and shrinkage as well as flexural strength and glass transition temperatures were evaluated for various comonomer compositions. Results Copolymerization of the bulky monomers with TEGDMA show higher conversion but similar shrinkage compared with Bis-GMA/TEGDMA controls. The resulting polymers have suitable mechanical strength properties for potential dental restorative materials applications. When copolymerized with PEGDMA, the bulky monomers show lower shrinkage, comparable conversion, and more homogeneous polymeric network structures compared with Bis-EMA/PEGDMA systems. Significance The novel dimethacrylate monomers with reduced reactive group densities can decrease the polymerization shrinkage as anticipated, but there is no significant evidence that the bulky substituent groups have any additional effect on reducing shrinkage based on the physical interactions as polymer side chains. The bulky groups improve the double bond conversion and help maintain the mechanical properties of the resulting polymer, which would otherwise decrease rapidly due to the reduced crosslinking density. Further, it was found that bulky monomers help produce more homogeneous copolymer networks.
The hypersonic environment: Required operating conditions and design challenges

Hypersonic flight powered by airbreathing engines offers the potential for faster response time at long ranges, and reduced cost for access-to-space. In the present paper the operating environment of typical hypersonic vehicles are discussed, including results for the radiation equilibrium wall temperature of external vehicle surfaces and the flow properties through three sample engines spanning the range of hydrocarbon-fueled Mach 4-8 flight and hydrogen-fueled flight at speeds up to Mach 17. Flow conditions at several locations through the sample engines were calculated to provide indications of the required operating flow environment. Additional system consideration such a seals, joints, vehicle integration and in-service engineering are addressed.
Upper Triassic—Lower Jurassic salt basin southeast of the Grand Banks

Abstract A grid of multichannel seismic reflection (MCS) profiles has been used to delineate and map a large, apparently tectonically controlled basin and associated diapiric province beneath the continental slope and rise southeast of the Grand Banks of Newfoundland. The depocenter, for which we propose the name Salar basin, is defined both landward and seaward by pronounced hinges in acoustic basement. It is approximately 400 km long, 35–70 km wide, and covers an area of approximately 20,000 km 2 . The southern end of the basin is marked by the intersection of the Southeast Newfoundland Ridge with the South Bank High on the Grand Banks, and the northern end is bounded by the southwestern margin of Flemish Cap. The Salar basin generally parallels the much smaller Carson basin, which lies beneath the Grand Banks immediately to the west, and it merges with this basin north of 45°22′N. Based upon correlation with contiguous deposits sampled by drilling in the Carson basin, we infer piercements filling the Salar basin to be mobilized Late Triassic-Early Jurassic evaporites, probably predominantly halite. A consequent early Mesozoic age for the Salar basin implies a multi-stage rifting history for the Newfoundland Basin, as has been documented for the adjacent Grand Banks. Initial extension, which probably formed the Salar basin's bounding basement hinge zones, occurred in Late Triassic—Early Jurassic time, and was associated with rifting of North America from Africa and extension in western Europe. The presence of early Mesozoic evaporites in a basin southeast of the Grand Banks suggests development of a significant, but shallow and restricted, seaway between the Grand Banks and the Iberian peninsula, probably connected northward with coeval salt provinces of northwestern Europe. A second rift phase related to separation of Iberia and the Grand Banks affected the Grand Banks and Salar basin in Late Jurassic to Early Cretaceous time, after a period of epeirogenic subsidence during the Early and Middle Jurassic. Uplift associated with this extension led to the development of the widespread “U” (Avalon) unconformity across the Grand Banks, the Salar basin and the Newfoundland Basin out to the J-Anomaly and may have induced the first halokinesis in the Salar basin. The second rift phase culminated in the initiation of seafloor spreading in mid-Early Cretaceous (Aptian) time at a location now marked by the J-Anomaly.
New approximations to J/sub 0/ and J/sub 1/ Bessel functions

New approximate solutions to the 0th- and 1st order Bessel functions of the first kind are derived. The formulations are based upon using a new integral with no previously known solution. The new integral in the limiting case is identical to the 0th-order Bessel function integral. It is solved in closed form, and the solution is expressed as a simple even order polynomial with integer coefficients. The polynomial coefficients are all of integer value. The 1st-order Bessel function approximation can then be found through a simple derivative. Comparisons are made between the exact solution, classic solutions, and the new approximation. The new approximation proves to be much more accurate than the classic small argument approximation. It is also sufficiently accurate to bridge the gap between the classic large and small argument approximations and has potential applications in allowing one to analytically evaluate integrals containing Bessel functions. >
Secondary electron trajectories in a Faraday cup magnetic field

Abstract Trajectories of electrons with energies between 10 eV and 1 MeV have been studied in inhomogeneous magnetic fields to choose a deflecting magnet for the capture of secondary electrons generated in the mouth of a Faraday cup. The results show that a solenoidal field abets their escape, but the field of two repelling bar magnets completely stops electrons with energies less than about 1 keV. Additional information relevant to Faraday cup design is also presented.
Posterior Reversible Encephalopathy Syndrome Associated with Hemodynamic Augmentation in Aneurysmal Subarachnoid Hemorrhage

Background Cerebral vasospasm has become the most concerning complication in patients with aneurysmal subarachnoid hemorrhage (aSAH) seen in the neurosciences intensive care unit (NSICU). Hemodynamic augmentation is frequently used to treat cerebral ischemia from vasospasm. In the last 5 years, posterior reversible encephalopathy syndrome (PRES) has been reported in three single case reports as a complication of hemodynamic augmentation. We describe an additional three patients seen in our institution.
Electrophysiologic effects of atropine on human sinus node and atrium

Electrophysiologic studies were conducted in 17 patients without apparent sinus node disease before and after intravenous administration of 1 to 2 mg of atropine. Mean values in milliseconds (+/- standard error of the mean) before and after administration of atropine were as follows: sinus cycle length 846 +/- 26.4 versus 647 +/- 20.0 (P less than 0.001); sinus nodal recovery time 1,029 +/- 37 versus 774 +/- 36 (P less than 0.001); mean calculated sinoatrial (S-A) conduction time 103 +/- 5.7 versus 58 +/- 3.9 (P less than 0.001); mean P-A interval 34 +/- 1.5 msec versus 31 +/- 1.5 (P less than 0.05); mean atrial effective and functional refractory periods during sinus rhythm 285 +/- 11.3 versus 238 +/- 7.9 and 331 +/0 11.6 versus 280 +/- 8.6, respectively (P less than 0.001 for both); mean atrial effective and functional refractory periods measured at equivalent driven cycle length 239 +/- 7.7 versus 213 +/- 7.4 and 277 +/- 11.4 versus 245 +/- 9.5, respectively (P less than 0.001 for both). In conclusion, atropine shortened sinus cycle length, sinus nodal recovery time and calculated S-A conduction time. The shortening of atrial refractory periods with atropine implies that vagotonia prolongs atrial refractoriness in man.
The Sunburn-Protecting Effect of Para-Aminobenzoic Acid1

Sunburn is caused by a narrow range of ultraviolet rays in the region of 2900-3100A units (1). Effective protection against sunburn can be achieved by external application of solutions, lotions, pastes and ointments containing chemicals which greatly absorb or reflect the rays in this zone of ultraviolet radiation.
Axial Fan Blade Tone Cancellation Using Optimally Tuned Quarter Wavelength Resonators

Fan noise challenges noise control engineers in developing products ranging in scale from small ventilation systems to large turbomachines. The dominant noise source in many axial fans is the tonal noise due to rotor/stator interactions at the fundamental blade passing frequency. Flow-excited resonators have been used in the past for minimizing blade tone sound pressure levels (SPLs) generated by centrifugal fans through means of secondary source cancellation. The focus of this research is to extend that cancellation method to axial fans by attaching flow-driven quarter wavelength resonators fitted with optimal mouth perforations around the perimeter of the fan's shroud. A ducted-fan test facility was developed to measure upstream and downstream noise radiated from a test fan. Resonators were mounted at specific locations around the fan's shroud to obtain reductions in blade tone SPLs in both flow directions. They were driven into resonance via the unsteady pressure from the passing blades. An analytical model using transmission line theory was developed and validated experimentally to characterize the resonator's behavior under various flow conditions and mouth geometries. This model was used to predict the resonator's potential for reducing in-duct blade tones for specific flows and mouth perforation patterns. In a series of experiments to obtain the optimal resonator mouth perforations, it was observed that upstream and downstream SPL attenuations require different placement of the resonator mouth relative to the blade of the fan. With a single tuned resonator it was demonstrated that the fundamental blade tone SPLs can be reduced by as much as 20 dB in either the upstream or the downstream duct but not in both directions simultaneously. This behavior results when combining the resonator's monopolelike sound field with the dipolelike sound field of the fan's blades. Further studies are underway to extend the above method to higher pressure fans operating at speeds that generate higher order duct modes.
Photoperiodic response of sexual reproduction in the Daphnia pulex group is reversed in two distinct habitats

Two traditional species in the Daphnia pulex group (D. pulex and D. pulicaria) are not completely reproductively isolated. The microhabitats they dominate are distinct but overlap geographically, and migration between the microhabitats is not uncommon. Their species identity is not fully supported by a recent molecular study. A laboratory experiment shows that Daphnia clones isolated from two populations of each species switch to sexual reproduction in response to totally different photoperiodic cues, so that their mating seasons are expected to differ. This phenomenon is most likely due to local adaptation of the two species to their respective distinct microhabitats. The phenomenon, together with the peculiarity of the study system, is interpreted as an ongoing allochronic speciation process in aquatic systems.
Heteroleptic platinum(II) isocyanide complexes: convenient synthetic access, polymorphs, and vapoluminescence

A convenient synthetic scheme was developed to access a series of square-planar Pt(II) complexes of the form (TBA)[Pt(CN)3(CNR)] (TBA = tetra-n-butyl ammonium cation, R = CH3, c-C6H11, p-(C2H5)-C6H4). These heteroleptic complexes were characterized by combustion analyses, single-crystal X-ray structure determinations, HRFAB-MS, 1H NMR, ATR-IR, solution UV-Vis, and solid-state emission spectroscopies. Surprisingly, each of these complexes exhibit low energy room temperature solid-state luminescence in the absence of intermolecular Pt–Pt interactions. Additionally, the polymorphic behavior of (TBA)[Pt(CN)3(CN-c-C6H11)] was elucidated through a combination of single-crystal X-ray structure determinations, X-ray powder diffraction, and mass uptake experiments. Vapoluminescence and polymorphic transformations of (TBA)[Pt(CN)3(CN-c-C6H11)] were concomitant with water vapor absorption. A new double-salt complex [Pt(terpy)Cl] [Pt(CN)3(CNCH3)] (terpy = 2,2′,6′,2′′-terpyridine) was also synthesized and characterized by combustion analysis, ATR-IR, HRFAB-MS, and solid-state UV-Vis and emission spectroscopies. The vapoluminescent properties of this salt in response to water were examined by mass uptake experiments, ATR-IR, and solid-state emission spectroscopy. A principal component analysis (PCA) of the solid-state emission changes induced by water vapor confirmed the presence of an intermediate emissive species.
Expression of angiogenic and vasculogenic proteins in the lung in alveolar capillary dysplasia/misalignment of pulmonary veins: An immunohistochemical study

Abstract Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a rare, universally fatal developmental disorder of the lung affecting both the parenchyma and the vasculature. Its cause remains incompletely understood; the occurrence of familial cases has suggested a genetic abnormality. While several candidate genes have been studied previously, the affected pathway(s) have not yet been fully defined. The expression patterns of 8 gene products (endothelial nitric oxide synthase-3, fetal liver kinase-1, hypoxia inducible factor 1α, Von Hippel Lindau protein, 3 vascular endothelial growth factors [VEGF147, VEGFC1, and VEGFA20], and activin receptor-like kinase 1), all known to have a role in vascular development in the lung, were studied in 13 ACD/MPV and 17 control lungs by immunohistochemistry to further address the underlying molecular abnormality. Expression was graded with regard to degree and extent for multiple components of the lung parenchyma and pulmonary vasculature for e...
Constructivism: Does your practice match your conceptual framework?

Abstract Though constructivism has been an epistemology espoused by early childhood educators since the field's inception; defining, understanding, and implementing a constructivist philosophy is challenging. This article includes an overview of constructivism, including the role of the learner and the teacher and the conditions that enhance learning. Also discussed will be distinct challenges that exist in the implementation of constructivism in a higher education setting. Practical strategies that universities have found to overcome these challenges are included.
On the absence of sample size effects in the computation of cross-correlation functions in liquid water

Abstract A molecular dynamics simulation of liquid water using 864 molecules has confirmed the existence of a range of statistical cross correlation functions observed in earlier simulations with a much smaller sample size of 108 molecules. The amplitude and time dependence of the correlation functions are essentially identical from both simulations, indicating that there are no sample size effects and that the correlation functions themselves are real and characteristic of the molecular liquid state of matter.
Deep Tillage and Crop Rotation Effects on Cotton, Soybean, and Grain Sorghum on Clayey Soils

Deep tillage (subsoiling) of clayey soils in the fall when the profile is dry is a new concept that results in increased yields and net returns from soybean [Glycine max (L). Merr.] grown without irrigation. Crop rotation may also result in increased crop yields. Field studies were conducted on Tunica clay (clayey over loamy, smectitic, nonacid, thermic, Vertic Haplaquept) near Stoneville, MS (33°26' N lat) to determine the individual and combined effects of fall deep tillage and crop rotations on crop yields and net returns. Treatments included monocrop cotton [Gossypium hirsutum (L.)], soybean, and grain sorghum [Sorghum bicolor (L.) Moench], and biennial rotations of cotton with grain sorghum and soybean with grain sorghum grown without irrigation and in either a conventional-till (CT) or deep-till (DT) production system. Yields from all cotton and soybean crop sequences grown in the DT respectively averaged 541 kg ha -1 and 525 kg ha -1 greater than comparable cotton (2184 kg ha -1 ) and soybean (2983 kg ha -1 ) crop sequences grown in the CT. Net returns from monocrop cotton ($552 ha -1 ) and soybean ($462 ha -1 ) in the DT respectively averaged $392 ha -1 and $121 ha -1 more than similar crop sequences in the CT. Rotations increased cotton and soybean yields but not net returns because of the low value of the grain sorghum component. These data indicate that fall deep tillage should be incorporated into monocrop cotton and soybean crop sequences to maximize and stabilize net returns from these crops on Tunica clay.
Mechanism of Amylin Fibrillization Enhancement by Heparin

We characterized the interaction of amylin with heparin fragments of defined length, which model the glycosaminoglycan chains associated with amyloid deposits found in type 2 diabetes. Binding of heparin fragments to the positively charged N-terminal half of monomeric amylin depends on the concentration of negatively charged saccharides but is independent of oligosaccharide length. By contrast, amylin fibrillogenesis has a sigmoidal dependence on heparin fragment length, with an enhancement observed for oligosaccharides longer than four monomers and a leveling off of effects beyond 12 monomers. The length dependence suggests that the negatively charged helical structure of heparin electrostatically complements the positively charged surface of the fibrillar amylin cross-β structure. Fluorescence resonance energy transfer and total internal reflection fluorescence microscopy experiments indicate that heparin associates with amylin fibrils, rather than enhancing fibrillogenesis catalytically. Short heparin fragments containing two- or eight-saccharide monomers protect against amylin cytotoxicity toward a MIN6 mouse cell model of pancreatic β-cells.
A-V Nodal Reentrant Tachycardia vs Accelerated A-V Junctional Rhythm in Acute Inferior Myocardial Infarction

This report describes initiation of A-V nodal reentrant tachycardia in a patient with acute inferior myocardial infarction. The onset of tachycardia was preceded by an abortive A-V nodal Wenckebach periodicity. A-V nodal ischemia with or without vagotonia was implicated as the cause of induction of critical functional dissociation between the two A-V nodal conduction pathways. Since the tachycardia manifested its rate between 95–110 beats/min during the evolutionary phase of acute inferior myocardial infarction, it simulated, electrocardiographically, an accelerated A-V junctional rhythm. Analysis of the onset of tachycardia was of diagnostic importance.
Worst-case choice for the stable marriage problem

Abstract We present a worst-case choice for the stable marriage problem which takes the maximum number of stages for Gale and Shapely's algorithm (1962). We also analyze a coroutine solution recently suggested by Allison (1983) as well as a parallel algorithm for this problem.
Impact of building service life models on life cycle assessment

Life cycle assessments (LCAs) of buildings often use an operational lifetime of approximately 50 years, and have simplified descriptions of building operations and maintenance. The typical service life period is inappropriate for some materials given their exposure and use, and the simplified descriptions do not fully represent maintenance, repair and replacement cycles. Building service life prediction modelling is examined to improve the representation of service life in LCA and the evaluation of environmental impacts. A process is developed that incorporates service life, operational energy and LCA modelling which provides a means of examining the effects of materials and systems in building operation, maintenance, repair and replacement. This process advances the field of building LCA by representing a more complete and accurate building life cycle, and by highlighting the impact of building service life models on the LCA methodological assumptions. Nine building envelope combinations are modelled. Cu...
Reproducibility of QBS gated blood pool SPECT LV and RV functional calculations

Abstract Background: The most widely distributed program for computing ejection fraction (EF), end-diastolic volume (EDV) and end-systolic volume (ESV) for both the left ventricle (LV) and right ventricle (RV) from gated blood pool SPECT (GBPS) data is the surface gradient method QBS (Cedars-Sinai Medical Center, Los Angeles, CA). This investigation examined QBS reproducibility and the amount of variation among planar-GBP and QBS LVEF's. Methods: Three technologists independently reconstructed and reoriented GBPS data, from which they independently computed cardiac functional parameters by QBS, and LVEF's from planar-GBP data, for 35 patients (age=59±12 years; 83% male) referred for CAD evaluation (27 with CHF and 25 with prior MI). No technologist altered any automatically-generated QBS outlines for any calculations. Results: All variables were found to be normally distributed (Kolmogorov-Smirnov test). EF, EDV and ESV correlations were significant among all data pairs for the LV (0.98, 0.96 and 0.99) and for the RV (0.74, 0.97 and 0.96) (multiple linear regression). Mean differences were non-significant and 95%-confidence upper limits and lower limits were modest for LVEF's but fairly wide for the other measurements. (Bland-Altman analysis; see Table). Planar LVEF Gated blood pool SPECT LVEF LVEDV LVESV RVEF RVEDV RVESV Upper limit +7% +9% −35 ml −29 ml +14% +34 ml +31 ml Difference 0% −1% −2 ml −2 ml 0% +1 ml −1 ml Lower limit −7% −6% +31 ml +24 ml −14% −31 ml −33 ml Conclusion: QBS ventricular function measurements agree well with those of planar-GBP and are reproducible, with LVEF variance comparable to that of planar-GBP.
Amounts and Distribution of Minerals in Washington Forages

Samples of alfalfa hay and grass silage from Washington state were analyzed for crude protein, neutral and acid detergent fiber, ash, and mineral content. Subsequently, neutral and acid detergent fiber factions were analyzed for mineral elements. Calcium, magnesium, and copper in alfalfa were negatively correlated with percent neutral and acid detergent fiber and positively correlated with percent crude protein. For grass silage, phosphorus, potassium, magnesium, and zinc were positively correlated with percent crude protein. Percent of total mineral in alfalfa associated with neutral detergent fiber was calcium 24%, phosphorus 31%, potassium 1%, magnesium 5%, copper 29%, zinc 31%, and iron 77%. Percent of total minerals located in the acid detergent fiber was calcium 3%, phosphorus not detectable, potassium 3%, magnesium 2%, copper 43%, zinc 23%, and iron 19%. Percents were similar for grass silage. Additionally, copper and calcium in the neutral detergent fraction and calcium in the acid detergent fraction decreased with higher neutral and acid detergent fiber. A significant portion of calcium, phosphorus, iron, zinc, and copper are associated with the fibrous portion of alfalfa hay and grass silage.
Cosmochemistry: A breath of solar air

The abundance of different isotopes of oxygen provides clues to the origin of matter in the Solar System. Hence the importance of studies of oxygen atoms from the Sun trapped in metal grains on the Moon.
LOCAL PUBLIC FINANCE AND ECONOMIC DEVELOPMENT: The Indonesian Context*

Author(s): Quigley, John M. | Abstract: This paper considers the relative centralization or decentralization of public finance, and relates the equity and efficiency issues ot the special features of developing economies. The paper considers the centralization of taxation and service provision in Indonesia in relation to these theoretical prinicples and indicates ways in which we may expect decentralization to proceed in the Indonesian context.
Thermodynamics of nonlinear bolometers near equilibrium

We present the first thermodynamically correct calculation of the noise in a simple nonlinear resistive bolometer or calorimeter operated out of equilibrium. The solution is rigorous only for first- and second-order deviations from equilibrium, and for the linear and quadratic terms of dissipative elements. In contrast, existing models of noise in resistive bolometers are based on the application of equilibrium theories to a system that is often nonlinear and out of equilibrium. We derive solutions applicable both in and out of steady state. The noise has power spectral density different from the equilibrium theory, and it has higher-order correlations and non-Gaussian characteristics. The results do not apply to non-Markovian hidden variables in the bolometer.
INTERACTION OF CATECHOLAMINE AND AMINO ACID METABOLISM IN BRAIN: EFFECT OF PARGYLINE AND l‐DOPA

— The combination of l-DOPA and pargyline caused a decrease in level of aspartate and an increase in that of glutamine in vivo in cerebral cortex, cerebellum, brain stem, hypothalamus, neostriatum and cervical cord of rat. There was also a decreased incorporation of radioactivity from [1-14C]acetate into amino acids in vivo, most notably in cerebellum and brain stem. The labelling of glutamine was especially affected. In addition, cortical slices were prepared from guinea pigs which had been pretreated with pargyline. These slices were incubated with and without 1 mm l-DOPA in media containing [1-14C]acetate. Pargyline alone caused a stimulation of the labelling of glutamate and aspartate but not glutamine and GABA; the levels of aspartate and GABA were greater than in control slices. The addition of l-DOPA to slices from pargylinized animals caused a severe decrease in glutamine labelling but not in that of glutamate or aspartate; the level of glutamine was increased while that of glutamate was decreased. The results are discussed in terms of the known biochemical and morphological compartmentation of amino acids in brain. It is suggested that catecholamines, in the process of functioning as transmitters, may also function as metabolic regulators of other transmitters, e.g. amino acids, as well as of the energy required for balanced neuronal function.
One Species but Two Patterns: Populations of the Hudsonian Godwit (Limosa haemastica) Differ in Spring Migration Timing

ABSTRACT. Climate change can cause mismatches between the breeding phenology and peak abundance of food resources of migratory species. Moreover, asynchronously changing climate regimes across their ranges may constrain the ability of migratory species to adapt to all the regimes they encounter. To understand the potential effect of asynchronous changes, I examined the influences of both large- and local-scale weather and climate on the timing of arrival of two disjunct breeding populations of Hudsonian Godwits (Limosa haemastica). I used arrival data from two study sites—Beluga River, Alaska, and Churchill, Manitoba—combined with 37 years of weather and climate data from both winter and stopover sites and the breeding grounds. The Alaskan population now arrives ∼9 days earlier than it did in the early 1970s, and the Churchill population arrives >10 days later. A model-selection process using linear regression models suggested that these divergent trends result from different suites of environmental facto...
Cell surface‐mediated cellular interactions: Effects of B104 neuroblastoma surface determinants on C6 glioma cellular properties

To study the influence of cell surface-associated molecules on intercellular communication, C6 glioma cells were cultured both on plastic and on substrata of paraformaldehyde-fixed B104 neuroblastoma cells. By then comparing the phenotypic expression of these “cocultured” C6 cells with cells cultured on tissue culture plastic, the influence of the cellular substratum was determined. The beta-adrenergic-responsive cyclic AMP-generating system of C6 cells was compared on these various substrata. We found that fixed beds of dibutyryl cyclic AMP (dbcAMP)-treated B104 cells uncoupled beta-receptors from adenylate cyclase, whereas fixed beds of similarly treated C6 cells did not. However, other cellular properties were not affected by growth atop fixed dbcAMP-treated B104 cell beds including the rate of C6 cellular proliferation and their rate of protein synthesis. The cell surface-associated determinant on B104 cells capable of uncoupling the beta-responsive cyclase system of C6 cells is probably a protein, as judged by its susceptibility to protease treatment. Other properties of C6 cells were also affected by the various substrata including basal and hydrocortisone-induced levels of glycerol phosphate dehydrogenase (GPDH; an oligodendroglial marker) and the rate of RNA synthesis in these cells.
Dependencies of high-latitude plasma convection: Consideration of interplanetary magnetic field, seasonal, and universal time factors in statistical patterns

[1] The database of the nine radars of the Super Dual Auroral Radar Network (SuperDARN) in the northern hemisphere has been analyzed for information on factors that influence the convection of plasma in the high-latitude ionosphere. The velocity measurements were collected over the period 1998–2002. The data were first used to derive a new statistical model of convection that improves upon the earlier one-radar model of Ruohoniemi and Greenwald (1996) in its specification of the dependence of the convection pattern on the magnitude and direction of the IMF in the GSM Y-Z plane. We then derived average patterns for secondary sortings by season, year, and radar. Such dependencies as emerged were most clearly seen by contrasting the results for By+ and By−. The seasonal effect in the convection pattern is found to have similarities to that of the sign of By. In particular, the combination of By+/summer (By−/winter) reinforces the tendency of the By sign factor to sculpt the dusk and dawn cells into more round/crescent (crescent/round) shapes and to shift the crescent cell across the midnight MLT meridian. However, these combinations are associated with lower estimates of the total cross polar cap potential drop, ΦPC, while the nonreinforcing combinations produce elevated ΦPC, especially By−/summer. There is an overall tendency for ΦPC to increase from winter to summer, although the pure seasonal effect on the potential drop is weaker than that of the By−sign/season factor. We did not find pronounced differences among the patterns derived for the 5 individual years, which spanned the most recent interval of solar cycle maximum. Sorting by radar, we found few differences among the patterns for By+, but for By−, variations emerged that are consistent with a possible dependence on universal time (UT). The impacts of season and UT on convection in the high-latitude ionosphere thus depends on the IMF, especially the sign of By. We speculate that variability in the ionospheric conductivity has a greater effect on magnetosphere-ionosphere coupling under By− conditions.
Shining a light on the bottom of the ocean: An examination of the cost estimation techniques for Lockheed Martin's Mission Systems & Sensors division

Accurate cost estimation is integral to Lockheed Martin's Mission Systems and Sensors proposal generation process. Overestimation can result in a loss of a contract and underestimation can result in a loss of profits. The authors set out to examine and improve this imprecise and unique process. The team conducted both quantitative and qualitative analysis to produce a set of recommendations suggesting potential process improvements. Additionally the team produced a prototype structure to aid Lockheed Martin in improving data storage methods in the future.
Undergraduate perceptions of the reference collection and the reference librarian in an academic library

Many undergraduate students have no clear idea of the purpose and function of the reference collection and the services offered by the reference librarian. Uncertainty about these resources may cau...
Effect of Selenium and Lipotropic Factors on Liver Fat Accumulation in Laying Hens

Abstract Two experiments were conducted with Single Comb White Leghorn laying hens to determine the effect of dietary additions of selenium, choline, inositol, vitamin B12 and vitamin E on liver fat accumulation and other criteria. In Experiment 1, adding 1 p.p.m. selenium to corn-soybean meal rations, with and without added fat, significantly reduced total fat accumulation per liver. Adding a combination of choline, inositol, vitamin B12 and vitamin E to the corn-soy diet without added fat significantly reduced liver fat accumulation and percent fat of the liver. On the other hand, a wheat-pea-fat basal containing about half the selenium content of the corn-soy diets resulted in a liver fat accumulation significantly lower than that observed with the corn-soy basal diets. Adding selenium or the lipotropic mix to this diet failed to significantly affect fat accumulation. None of the dietary treatments significantly affected egg production, egg weight, and body weight changes. In the second experiment, individually supplementing a corn-soy-fat basal ration with vitamin E, inositol, vitamin B12, choline and selenium or combinations of these nutritional factors failed to significantly affect liver fat accumulation or other criteria measured. The fat accumulation tended to be lower with choline supplementation, but the effects were not statistically significant (P > .05).
Electrical modulation of ion concentration in dual-gated nanochannels

Coupled Poisson-Nernst-Planck and Stokes simulations demonstrate the operating principles of using electrical biases in dual-gated nano-fluidic channels to create localized and tunable solution zones of either depleted or accumulated ions. Scaling studies reveal that such ion modulations overcome the limit of counter-ion screening and remain effective even for channel widths greatly exceeding the Debye screening length. The underlying mechanism is attributed to the transport-induced de-screening of gating potentials.
The influence of the major ions of seawater on the adsorption of simple organic acids by goethite

The adsorption of oxalic, phthalic, salicylic, and lactic acids on goethite from 0.53 M NaCl and from synthetic major ion sea water is examined to determine the effect of Mg, Ca, and SO/sub 4/ on the adsorption behavior of the organic compounds. The comparison shows that organic acid adsorption is suppressed in sea water relative to the NaCl system. Successive additions of SO/sub 4/, Mg, and Ca in their natural ionic proportions found in sea water to 0.53 M NaCl indicate that sulfate suppresses the adsorption of all the organic acids, especially in the low pH range. The addition of Mg also suppresses the adsorption of oxalic and phthalic acids while the addition of Ca suppresses lactic acid adsorption. The effect of SO/sub 4/, Mg and Ca on the adsorption of the organic acids is due to competition for available binding sites and the formation of solution complexes which either do not absorb or weakly absorb.
Cardiovascular magnetic resonance assessment of ventricular function and myocardial scarring before and early after repair of anomalous left coronary artery from the pulmonary artery.

Background: In patients with anomalous left coronary artery from the pulmonary artery (ALCAPA) left ventricular (LV) dilatation and dysfunction evolves due to diminished myocardial perfusion caused by coronary steal phenomenon. Using late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) imaging, myocardial scarring has been shown in ALCAPA patients late after repair, however the incidence of scarring before surgery and its impact on postoperative course after surgical repair remained unknown. Methods: 8 ALCAPA-patients (mean age 10.0 ± 5.8 months) underwent CMR before and early after (mean 4.9 ± 2.5 months) coronary reimplantation procedures. CMR included functional analysis and LGE for detection of myocardial scars. Results: LV dilatation (mean LVEDVI 171 ± 94 ml/m 2 ) and dysfunction (mean LV-EF 22 ± 10 %) was present in all patients and improved significantly after surgery (mean LVEDV 68 ± 42 ml/m 2 , p = 0.02; mean LV-EF 58 ± 19 %, p<0.001). Preoperative CMR revealed myocardial scarring in 2 of the 8 patients and did not predict postoperative course. At follow-up CMR, one LGE-positive patient showed delayed recovery of LV function while myocardial scarring was still present in both patients. In two patients new-onset transmural scarring was found, although functional recovery after operation was sufficient. One of them showed a stenosis of the left coronary artery and required resurgery. Conclusions: Despite diminished myocardial perfusion and severely compromised LV function, myocardial scarring was preoperatively only infrequently present. Improvement of myocardial function was independent of new-onset scarring while the impact of preoperative scarring still needs to be defined.
Interactive display of large NURBS models

We present algorithms for interactive rendering of large-scale NURBS models. The algorithms convert the NURBS surfaces to Bezier surfaces, tessellate each Bezier surface into triangles, and render them using the triangle-rendering capabilities common to current graphics systems. We present algorithms for computing tight bounds on surface properties in order to generate high quality tessellation of Bezier surfaces. We introduce enhanced visibility determination techniques and present methods to make efficient use of coherence between successive frames. In addition, we also discuss issues in parallelization of these techniques. The algorithm also avoids polygonization anomalies like cracks. Our algorithms work well in practice and, on high-end graphics systems, are able to display models described using thousands of Bezier surfaces at interactive frame rates.
Glycogen Synthase Kinase-3β Inhibition Ameliorates Cardiac Parasympathetic Dysfunction in Type 1 Diabetic Akita Mice

Decreased heart rate variability (HRV) is a major risk factor for sudden death and cardiovascular disease. We previously demonstrated that parasympathetic dysfunction in the heart of the Akita type 1 diabetic mouse was due to a decrease in the level of the sterol response element–binding protein (SREBP-1). Here we demonstrate that hyperactivity of glycogen synthase kinase-3β (GSK3β) in the atrium of the Akita mouse results in decreased SREBP-1, attenuation of parasympathetic modulation of heart rate, measured as a decrease in the high-frequency (HF) fraction of HRV in the presence of propranolol, and a decrease in expression of the G-protein coupled inward rectifying K+ (GIRK4) subunit of the acetylcholine (ACh)-activated inward-rectifying K+ channel (IKACh), the ion channel that mediates the heart rate response to parasympathetic stimulation. Treatment of atrial myocytes with the GSK3β inhibitor Kenpaullone increased levels of SREBP-1 and expression of GIRK4 and IKACh, whereas a dominant-active GSK3β mutant decreased SREBP-1 and GIRK4 expression. In Akita mice treated with GSK3β inhibitors Li+ and/or CHIR-99021, Li+ increased IKACh, and Li+ and CHIR-99021 both partially reversed the decrease in HF fraction while increasing GIRK4 and SREBP-1 expression. These data support the conclusion that increased GSK3β activity in the type 1 diabetic heart plays a critical role in parasympathetic dysfunction through an effect on SREBP-1, supporting GSK3β as a new therapeutic target for diabetic autonomic neuropathy.
Multiple T Cell Subsets Control Francisella tularensis LVS Intracellular Growth Without Stimulation Through Macrophage Interferon γ Receptors

A variety of data suggest that in vivo production of interferon (IFN)-γ is necessary, but not sufficient, for expression of secondary protective immunity against intracellular pathogens. To discover specific IFN-γ–independent T cell mediated mechanisms, we took advantage of an in vitro culture system that models in vivo immune responses to the intracellular bacterium Francisella tularensis live vaccine strain (LVS). LVS-immune lymphocytes specifically controlled 99% of the growth of LVS in wild-type murine bone marrow–derived macrophages. Surprisingly, LVS-immune lymphocytes also inhibited LVS intracellular growth by as much as 95% in macrophages derived from IFN-γ receptor knockout (IFNγR KO) mice. CD8+ T cells, and to a lesser degree CD4+ T cells, controlled LVS intracellular growth in both wild-type and IFNγR KO macrophages. Further, a unique population of Thy1+αβ+CD4−CD8− cells that was previously suggested to operate during secondary immunity to LVS in vivo strongly controlled LVS intracellular growth in vitro. A large proportion of the inhibition of LVS intracellular growth in IFNγR KO macrophages by all three T cell subsets could be attributed to tumor necrosis factor (TNF) α. Thus, T cell mechanisms exist that control LVS intracellular growth without acting through the IFN-γ receptor; such control is due in large part to TNF-α, and is partially mediated by a unique double negative T cell subpopulation.
Wireless control of powered wheelchairs with tongue motion using tongue drive assistive technology

Tongue Drive system (TDS) is a tongue-operated unobtrusive wireless assistive technology, which can potentially provide people with severe disabilities with effective computer access and environment control. It translates users' intentions into control commands by detecting and classifying their voluntary tongue motion utilizing a small permanent magnet, secured on the tongue, and an array of magnetic sensors mounted on a headset outside the mouth or an orthodontic brace inside. We have developed customized interface circuitry and implemented four control strategies to drive a powered wheelchair (PWC) using an external TDS prototype. The system has been evaluated by five able-bodied human subjects. The results showed that all subjects could easily operate the PWC using their tongue movements, and different control strategies worked better depending on the users' familiarity with the TDS.
A 2Gbps RF-correlation-based impulse-radio UWB transceiver front-end in 130nm CMOS

The design of a carrier-less RF-correlation-based IR-UWB TRX front-end in 130nm CMOS is presented. Timing synchronization and coherent demodulation are implemented directly in the RF domain, enabling energy-efficient wireless communication at Gb/s data rates. A 25ps timing resolution is achieved by a two-step synchronizer. Occupying 6.4mm2 chip area, the TRX achieves a maximum data rate of 2Gbps and an RX sensitivity of −64dBm with a BER of 10−5, while requiring only 51.5pJ/pulse in the TX mode and 72.9pJ/pulse in the RX mode.
Scapegoating firm performance: Which CEOs get away with it?

This article examines research that focused on the phenomenon of chief executive officer (CEO) dismissal and the role of power influence in the dismissal process. The article discusses research conducted by Professor Warren Boeker of Columbia University about executive dismissal in the semiconductor industry. Boeker examined factors that lead to CEO dismissal and succession and discusses various actions that could be taken by a firm regarding management dismissal. The author discusses some of the research findings which indicated that there was a relationship between CEO power, lowered organizational performance and dismissal. The author also notes that in poor performing organizations where the CEO is powerful, members of management are likely to be scapegoat targets.
Neoplasms of the hepatobiliary system: clinical presentation, molecular pathways and diagnostics

Neoplasms of the hepatobiliary system include primary tumors, such as hepatocellular carcinoma and cholangiocarcinoma, and secondary lesions from the metastatic spread of a cancer of nonhepatobiliary origin. Surgical excision remains the mainstay of long-term survival for primary tumors whereas secondary lesions can be treated by multiple modalities, including resection, radiotherapy and radiofrequency ablation. However, diagnosis of hepatobiliary neoplasms often occurs late in the disease process. In this article we will focus on the diagnostic approaches and new molecular diagnostics of primary hepatobiliary cancers and we will discuss how these new developments may impact the detection and management of these recalcitrant cancers.
1s Sociolinguistics Lacking in Style

Althouglz the study of stylistic variation has been a feature of much sociolitlguistic inilestigation since the 1960fs, there is little agreement ahout the nature of this variation and the extent to which it can (or should) be ini9estigated systemntically. There are at least three problems: i) a tendeno. to treat stylistic i3ariation as unidimensional; ii) lack of clarity about the injiuence of the written language; and iii) a failure to examine the role of al1 the participants in interviews. Preoccupation with a narrow iiew of stylistic variation muy have constrained sociolinguistic ini.estigation and rendered it less useful thati it might have been. One of tlze most impressive features of Labov's pioneering work in Neiil York (Labois 1966) wJas its e.~tended description of the methodology he employed, which has proiided tlze model for much of the subsequent sociolinguistic ini3estigation of urban speech. However, as O'Connell (1 988) pointed out with respect to the historj of ps.ychology, there is a tendency for tlze suhtleties and limitations of earlier studies to he obscured in later citations. This paper is un examination of some of the evidence that I~as heen used in support of various approaches to the collection uf sociolinguistic data. Inevitably, this involves criticalb re-examining some studies tlzat haiqe been frequently cited in the literature but I belieiie there is a value in looking closely again at the evidence and the assumptions in these works so that future studies mq be hased on sound metlzodology. (Keywords: stylistic variation. sociolinguistic methodology, written language. speech accomrnodation. scottish dialect).
Electron tomography of RabA4b- and PI-4Kβ1-labeled trans Golgi network compartments in Arabidopsis.

The trans Golgi network (TGN) of plant cells sorts and packages Golgi products into secretory (SV) and clathrin-coated (CCV) vesicles. We have analyzed of TGN cisternae in Arabidopsis root meristem cells by cell fractionation and electron microscopy/tomography to establish reliable criteria for identifying TGN cisternae in plant cells, and to define their functional attributes. Transformation of a trans Golgi cisterna into a Golgi-associated TGN cisterna begins with cisternal peeling, the formation of SV buds outside the plane of the cisterna and a 30–35% reduction in cisternal membrane area. Free TGN compartments are defined as cisternae that have detached from the Golgi to become independent organelles. Golgi-associated and free TGN compartments, but not trans Golgi cisternae, bind anti-RabA4b and anti-phosphatidylinositol-4 kinase (PI-4K) antibodies. RabA4b and PI-4Kβ1 localize to budding SVs in the TGN and to SVs en route to the cell surface. SV and CCV release occurs simultaneously via cisternal fragmentation, which typically yields ∼30 vesicles and one to four residual cisternal fragments. Early endosomal markers, VHA-a1-green fluorescent protein (GFP) and SYP61-cyan fluorescent protein (CFP), colocalized with RabA4b in TGN cisternae, suggesting that the secretory and endocytic pathways converge at the TGN. pi4k1/pi4k2 knockout mutant plants produce SVs with highly variable sizes indicating that PI-4Kβ1/2 regulates SV size.