cssi/SciSciGPT-SciSciNet huggingface dataset:
Attitudinal and behavioral variables related to participation in union activities

A questionnaire was administered to 500 union members. A multiple regression equation was developed using a multi-faceted index of union participation as the criterion with 25 predictor variables: 14 factor scores developed through factor analysis, 9 demographic variables, and 2 measures of perceived control within local unions. There was little shrinkage in the multiple R after double cross-validation. Community-political activities, liberal political beliefs, pro-unionism philosophies, high standards of involvement with unions, and high general job satisfaction-involvement were the five best predictors of union participation. Active union members may view unions as part of a socio-political movement above and beyond their economic and protective functions.
The neutron-deuteron scattering lengths

Abstract New data on coherent and incoherent neutron-deuteron scattering permit re-evaluation of the doublet and quartet scattering lengths, with the results 4 a = 6.14 ± 0.06 fm , and 2 a = 0.11 ± 0.07 fm . These values imply σ free = 3.14 ± 0.06 b. A comparison has been made with the values obtained from extrapolations of the 4 S and 2 S phase shifts for n-d and p-d elastic scattering. Fot the n-d 2 S phase shifts it is found that the effective range expansion has a pole at a negative energy ( E lab ≅ −0.1 MeV).
Initial experience with the CDF layer 00 silicon detector

We report on initial experience with the CDF Layer 00 Detector. Layer 00 is an innovative, low-mass, silicon detector installed in CDF during the upgrade for Run 2A of the Tevatron. Noise pickup present during operation at CDF is discussed. An event-by-event pedestal correction implemented by CDF is presented. This off-line solution prevents L00 from being used in the current incarnation of the on-line displaced track trigger. Preliminary performance of Layer 00 is described.
Shadowing growth of biaxially textured nanostructured films

Microstructure of a nanostructured film is not only of fundamental scientific interest but also an important subject from the practical point of view. In this paper we will discuss the formation of biaxially textured film under extreme shadowing during growth. Biaxially textured films are not single crystals, but they possess both the out-of-plane and in-plane preferred orientations. We will also discuss our newly developed reflection high-energy electron diffraction (RHEED) surface pole figure technique and how we employ this technique to capture the evolution of growth front texture.
The effect of mental calculation on stabilization of posture in a dynamic virtual environment

We explored the trade-off between simultaneous demands of attention to a mental calculation task, visual motion, and postural stabilization. Six healthy adults (23 ± 0.97 yrs) performed a balance task and a secondary calculation task in a stationary or translating immersive virtual reality environment. Coupling of visual and base of support motion produced the greatest postural destabilization. Addition of the calculation task appeared to diminish rather than magnify postural instability. Thus, the effect of cognitive load and attention on balance may depend upon the characteristics of the particular cognitive task.
Viscosity and thermal conductivity of nanofluids containing multi-walled carbon nanotubes stabilized by chitosan

Thermal conductivity, viscosity, and stability of nanofluids containing multi-walled carbon nanotubes (MWCNTs) stabilized by cationic chitosan were studied. Chitosan with weight fraction of 0.1%, 0.2 wt%, and 0.5 wt% was used to disperse stably MWCNTs in water. The measured thermal conductivity showed an enhancement from 2.3% to 13% for nanofluids that contained from 0.5 wt% to 3 wt% MWCNTs (0.24 to 1.43 vol %). These values are significantly higher than those predicted using the Maxwell's theory. We also observed that the enhancements were independent of the base fluid viscosity. Thus, use of microconvection effect to explain the anomalous thermal conductivity enhancement should be reconsidered. MWCNTs can be used either to enhance or reduce the fluid base viscosity depending on the weight fractions. In the viscosity-reduction case, a reduction up to 20% was measured by this work. In the viscosity-enhancement case, the fluid behaved as a non-Newtonian shear-thinning fluid. By assuming that MWCNT nanofluids behave as a generalized second grade fluid where the viscosity coefficient depends upon the rate of deformation, a theoretical model has been developed. The model was found to describe the fluid behavior very well.
Method for reducing routing overhead for mobile Ad Hoc network

In this paper, we propose a method to reduce the routing overhead in DSDV (Destination-Sequenced Distance-Vector) networks. The proposed method benefits from the nature of DSDV, such as loop-free and shortest routing path, but alleviates the problem of control message flooding when the network topology changes. Given a destination node in a DSDV network, there exists a spanning tree using the destination node as its root and constructed by the paths from all nodes to this destination. Based on this concept, we develop a mechanism for each node in mobile environment to dynamically identify its role (internal node or leaf node) in each spanning tree. When receiving a routing message from a destination node, the node checks its role in a corresponding spanning tree and determines whether the message should be forwarded. The proposed method is especially suitable for mobile Ad Hoc network with high node density, where the scarce bandwidth resource is effectively saved by filtering out the redundant routing messages at leaf nodes.
Comparative analysis of cellulose preparation techniques for use with 13C, 14C, AND 18O isotopic measurements.

A number of operationally defined methods exist for pretreating plant tissues in order to measure C, N, and O isotopes. Because these isotope measurements are used to infer information about environmental conditions that existed at the time of tissue growth, it is important that these pretreatments remove compounds that may have exchanged isotopes or have been synthesized after the original formation of these tissues. In stable isotope studies, many pretreatment methods focus on isolating “cellulose” from the bulk tissue sample because cellulose does not exchange C and O isotopes after original synthesis. We investigated the efficacy of three commonly applied pretreatment methods, the Brendel method and two variants of the Brendel method, the Jayme−Wise method and successive acid/base/acid washes, for use on three tissue types (wood, leaves, roots). We then compared the effect of each method on C and O isotope composition (13C, 14C, 18O), C and N content, and chemical composition of the residue produced (...
Prediction of interior noise due to random acoustic or turbulent boundary layer excitation using statistical energy analysis

The feasibility of predicting interior noise due to random acoustic or turbulent boundary layer excitation was investigated in experiments in which a statistical energy analysis model (VAPEPS) was used to analyze measurements of the acceleration response and sound transmission of flat aluminum, lucite, and graphite/epoxy plates exposed to random acoustic or turbulent boundary layer excitation. The noise reduction of the plate, when backed by a shallow cavity and excited by a turbulent boundary layer, was predicted using a simplified theory based on the assumption of adiabatic compression of the fluid in the cavity. The predicted plate acceleration response was used as input in the noise reduction prediction. Reasonable agreement was found between the predictions and the measured noise reduction in the frequency range 315-1000 Hz.
Review of Observing System Simulation Experiments to evaluate the potential impact of lidar winds on weather prediction

Observing System Simulation Experiments (OSSEs) are an important tool for evaluating the potential impact of proposed new observing systems, as well as for evaluating trade-offs in observing system design, and in developing and assessing improved methodology for assimilating new observations. Extensive OSSEs have been conducted at NASA/GSFC and NOAA/AOML in collaboration with Simpson Weather Associates and operational data assimilation centers over the last 25 years. These OSSEs determined correctly the quantitative potential for several proposed satellite observing systems to improve weather prediction prior to their launch, and evaluated trade-offs in orbits, coverage, and accuracy for space-based wind lidars. In this paper, we summarize OSSE methodology and present results from OSSEs to assess the potential impact of lidar winds.
Quantitative Comparison of Five SERS Substrates: Sensitivity and Limit of Detection

Five surface-enhanced Raman scattering (SERS) substrates were quantitatively compared for ease of preparation, sensitivity, limit of detection (LOD), reproducibility, and stability. Specifically, vapordeposited Ag films, electrochemically roughened Ag electrodes, nitric acid-etched Ag foil, Tollens-produced Ag films, and photoreduced Ag films on TiO were examined. Of these substrates, post2 deposition-annealed Ag films exhibited the greatest sensitivity and lowest LOD, with 152 +/- 1 counts per femtomole and an LOD of 0.36 +/- 0.02 femtomoles of trans -1,2-bis(4-pyridyl)ethene (BPE). The substrate demonstrating the poorest sensitivity and highest LOD was Ag deposited from the Tollens reaction, with 0.38 +/- 0.01 counts per femtomole and an LOD of 270 +/- 20 femtomoles of BPE. The easiest substrate to prepare, nitric acid-etched Ag foils, exhibited a sensitivity of 0.485 +/- 0.008 counts per femtomole and an LOD of 200 +/- 10 femtomoles of BPE.
Laser micro- and nanofabrication of biomaterials

Over the past half century, rapid progress has been made in laser-based medical diagnosis and treatment as well as in laser-based medical device fabrication. Lasers have unique capabilities for coating, machining, melting, polymerizing, sintering, and welding materials that are used in implantable and transdermal medical devices. In this review, academic and industrial developments involving laser processing of materials for dental, orthopedic, neural, ophthalmic, cardiovascular, and transdermal applications are described. In addition, laser processing of nanoscale materials for medical applications is discussed. Finally, challenges associated with commercialization of laser biomaterials are considered. Due to the unique capabilities provided by laser-based processes, it is anticipated that the use of laser biomaterials in implantable and transdermal medical devices will markedly increase over the coming years.
Long-term prescribed burning increases nutrient uptake and growth of loblolly pine seedlings

Abstract Loblolly pine ( Pinus taeda L.) seedlings were grown from seed in a greenhouse on A1 horizon soil collected from field plots that have been burned each winter or maintained in an unburned condition for 33 years. Soils from burned and unburned plots were treated with phosphorus (P), P and calcium (Ca), or left untreated. After 32 weeks, height, biomass, and nitrogen (N) and P uptake were greater on soil from burned versus unburned plots, although application of P masked these effects. Addition of P increased plant biomass, seedling height, and uptake of N and P, but depressed levels of soil NH 4 N. These results suggest that long-term prescribed burning may have a positive effect on nutrient availability that will benefit seedlings of the next stand.
Intraductal Carcinoma of the Prostate Without Invasive Carcinoma on Needle Biopsy: Emphasis on Radical Prostatectomy Findings

Purpose: Limited information is available on radical prostatectomy findings in men with intraductal carcinoma of the prostate on needle core biopsy in the absence of invasive prostate cancer.Materials and Methods: From the consulting files of one of us we identified 83 men in whom biopsy showed only intraductal prostate cancer. Followup was available in 66 cases. We reviewed slides in 21 radical prostatectomy cases.Results: Treatment was radical prostatectomy in 23 men, radiation therapy in 15, hormone therapy in 8 and radiation plus hormone therapy in 15 while 5 underwent no treatment or repeat biopsy. Of the 21 radical prostatectomies available for review findings revealed pathological stage pT3a in 8 (38%), pT3b in 3 (13%), pT2 in 8 (38%) and intraductal carcinoma without identifiable invasive cancer in 2 (10%). One patient with pT3a had a positive lymph node at surgery. Average Gleason score was 7.9. Three patients (14%) experienced post-prostatectomy biochemical failure and another (5%) had bone meta...
Ion structure determinations and ion—molecule reactions by double quadrupole mass spectrometry

Abstract The QQ mass spectrometer is shown to be applicable to ion structure determination via collision-induced dissociations of mass-selected ions. The instrument can be scanned so as to record the products of dissociation as well as those of ion—molecule association reactions. The dissociations correspond to those observed at high kinetic energy in mass-analyzed ion kinetic energy spectrometers and the association reactions show parallels with reactions seen in ion cyclotron resonance spectroscopy and in high-pressure mass spectrometry
Densitometric assessment of regional left ventricular systolic function during graded ischemia in the dog by use of dual-energy digital subtraction ventriculography

Densitometric analysis of images obtained by digital subtraction angiography (DSA) allows for more reproducible and less operator-dependent quantitation of ventricular function. Conventional DSA uses temporal subtraction but is limited by misregistration artifacts. Dual-energy digital subtraction angiography (DE-DSA) is immune to such misregistration artifacts. The ability of DE-DSA to quantitate changes in regional ventricular volume resulting from ischemia was tested. Densitometric analysis of both phase-matched and ejection fraction DE-DSA images was used to quantitate regional left ventricular systolic function during four levels of ischemia ranging from mild to severe in open-chest dogs (n = 10). DE-DSA left ventriculograms were obtained by means of central venous injections of iodinated contrast medium. Ischemia was graded according to percentage of systolic wall thickening as measured by sonomicrometry. Phase-matched end-systolic images were obtained at each of four levels of ischemia by subtracting an end-systolic control image from each end-systolic ischemic image. Ejection fraction images were obtained at the control level and at each level of ischemia by subtracting an end-systolic image from an end-diastolic image of the same cardiac cycle. The resulting wall motion difference signals represent the changes in regional ventricular volumes and were quantitated by densitometry. Densitometry was able to detect the effect of all levels of ischemia on regional function, even the mildest. Densitometric analysis of both phase-matched and ejection fraction DE-DSA images provides a sensitive technique for detecting and quantitating the changes in regional left ventricular systolic volume that occur with ischemia.
SU‐E‐T‐414: 4D Vs 3D Dose Calculations for Non‐Small‐Lung‐Cancer: A Comparison Using Tumor Control Probability (TCP)

Purpose: To investigate the utility of four dimensional (4D) dose calculations for design and optimization of stereotactic lung radiotherapy treatment plans. Methods: Radiotherapy plans for stage I–IIlung cancer were created for 8 patients. Clinically acceptable treatment plans were created with dose calculated on the end‐exhale 4D‐CT phase, using a Monte Carlo algorithm. Dose was then projected onto the remaining 9 phases of 4D‐CT using the Monte Carlo algorithm and accumulated onto the end‐exhale phase using commercially available deformable registration software. The resulting DVHs of the gross tumor volume (GTV), planning tumor volume (PTV), and PTVsetup were compared according to target coverage and dose. The PTVsetup was defined as a volume including the GTV and a margin for setup uncertainties but not for respiratory motion. Tumor control probabilities (TCP) resulting from these DVHs were estimated using a wide range of alphas, betas, and tumor cell densities. Results: Differences of up to 5 Gy were observed in dosimetric indices related to the tumor between 3D and 4D calculations. When the TCP was calculated using the resulting DVHs for fractionation schedules typically used in stereotactic body radiation therapy (SBRT), the TCP differed at most by 5% between 4D and 3D cases, and in most cases differed less than 1%. Conclusion: In some cases moderate dosimetric differences may be obtained between 3D and 4D dose calculations. Even when dosimetric differences exist between 3D and 4D calculations, the resulting TCPs do not differ greatly for commonly‐used SBRT dose prescriptions.
Osteoporosis Health Beliefs of Women with Increased Risk of the Female Athlete Triad

Women with increased risk of the female athlete triad (Triad) are more susceptible to osteoporosis compared to other women. The study included 65 women with increased risk of the Triad who had their osteoporosis health beliefs measured to assess their concern for the disease. Participants were female collegiate cross-country runners at different levels of competition, including National Association of Intercollegiate Athletics (NAIA) and National Collegiate Athletic Association (NCAA) Divisions III, II, and I. Although these participants have an increased risk of the Triad and are more susceptible to osteoporosis, on a scale of 1 to 5, results showed that they had low to moderate perceived susceptibility to osteoporosis with a mean score as high as 2.81 and moderate perceived severity of osteoporosis with a mean score as high as 3.38. A statistically significant difference in perceived susceptibility to osteoporosis was found between female collegiate cross-country runners in the NAIA and those in the NCAA DIII. Reasons that could explain relatively low levels of concern for osteoporosis in female collegiate cross-country runners and reasons for significant differences in perceived susceptibility to osteoporosis are given, and recommendations for health education and intervention to help care for this population are provided.
Condensed-matter physics: Hidden is more

Physicists have puzzled over a hidden electronic order in a uranium-based material for decades. A new theory attributes it to not just a single but a double breaking of time-reversal symmetry. See Article p.621 At temperatures below 17.5 K, the heavy-fermion uranium compound URu2Si2 exists in a mysterious 'hidden-order' phase that has eluded characterization for 25 years. In this study the authors have used various pieces of experimental evidence to establish the nature of the spontaneous phase transition that takes place at 17.5 K, and conclude that both single and double time-reversal symmetry occur, resulting in mixing of itinerant conduction electrons and localized 'Ising' states in the 5f2 orbital of uranium atoms. This is a fundamentally new type of order, which the authors dub hastatic (from the Latin hasta, a spear), and which they say could be a phenomenon that applies to other systems in which mixing with f-orbital states takes place.
Application of Spectral Mixture Analysis and Image Fusion Techniques for Image Sharpening

Abstract Image fusion is used to merge images of different spatial and spectral resolutions to create a high spatial resolution multispectral combination. High spectral resolution allows identification of materials in the scene, while high spatial resolution locates those materials. Spectral mixing is an algorithm that estimates the percentage of each material (called endmembers) within each low resolution multi/hyperspectral pixel. In this article we extend the spectral mixing (unmixing) approach to use one or more higher resolution sharpening images, locating the endmembers to higher spatial accuracy. The approach starts with conventional unmixing to generate fraction images. Constrained optimization techniques spatially locate the endmembers to high resolution. Synthetic image generation (SIG) tools are used to generate test images. SIG controls all the image parameters, making it easier to analyze algorithm performance. The results show spectral mixing material maps can be successfully sharpened, increasing the effective resolution of the hyperspectral images. Accurate fusion algorithms integrate spectral and spatial information into a single image, presenting the most information to an analyst.
Muscarinic cholinergic stimulation of the nitric oxide-cyclic GMP signaling system in cultured rat sensory neurons.

Abstract Acetylcholine or carbachol stimulated cyclic GMP production in neuronal cultures from embryonic rat dorsal root ganglia but not in non-neuronal dorsal root ganglia cultures. Acetylcholine stimulation of cyclic GMP production was mediated by muscarinic receptors and required extracellular Ca 2+ . Basal cyclic GMP production and acetylcholine-evoked cyclic GMP production were attenuated by Methylene Blue, suggesting the involvement of soluble guanylate cyclase and nitric oxide synthase. l - N G -Monomethyl arginine attenuated basal, acetylcholine or carbachol-stimulated cyclic GMP production; this inhibition of acetylcholine and carbachol stimulation of cyclic GMP was reversed by l -arginine. These results suggest that a nitrosyl factor mediates basal, as well as acetylcholine- and carbachol-stimulated, cyclic GMP production. Selective destruction of small diameter neurons by capsaicin pretreatment of dorsal root ganglion neuronal cultures abolished acetylcholine and capsaicin stimulation of cyclic GMP, but did not affect sodium nitroprusside stimulation of cyclic GMP. These results suggest that acetylcholine evoked production of a nitrosyl factor in capsaicin-sensitive (small diameter) sensory neurons, which subsequently stimulated a soluble guanylate cyclase and cyclic GMP production in adjacent neuronal and/or non-neuronal cells. These results demonstrate that muscarinic agonists stimulate the nitric oxide-cyclic GMP signalling system in capsaicin-sensitive sensory neurons. Thus, the noxious character of acetylcholine when administered peripherally may be mediated by nitric oxide-cyclic GMP.
Preparation and characterization of sulfoxides of S-adenosyl-L-homocysteine and S-ribosyl-L-homocysteine.

Abstract The results of oxidation studies with S -adenosylhomocysteine and S -ribosylhomocysteine revealed that these compounds were not as readily oxidized with hydrogen peroxide as l -methionine. However, by increasing the molar ratio of H 2 O 2 to S-compound and prolonging the reaction time, oxidation to the sulfoxide stage went to completion. The sulfoxides could be crystallized from aqueous solutions. Results of chemical, elemental, and spectral analysis indicate the chemical structures of these compounds to be the sulfoxides of S -adenosyl- l -homocysteine and S -ribosyl- l -homocysteine. Elemental analysis and spectroscopic data presented are consistent with the previously assigned structure for S -ribosyl- l -homocysteine. Spectroscopic data indicate that this compound is a mixture of the epimeric hemiacetals. Improvements in the procedure for the preparation of S -adenosyl- l -homocysteine are also presented.
Prospects and challenges of touchless electrostatic detumbling of small bodies

Abstract The prospects of touchlessly detumbling a small, multiple meters in size, space object using electrostatic forces are intriguing. Physically capturing an object with a large rotation rate poses significant momentum transfer and collision risks. If the spin rate is reduced to less than 1 deg/s, relative motion sensing and control associated with mechanical docking becomes manageable. In particular, this paper surveys the prospects and challenges of detumbling large debris objects near Geostationary Earth Orbit for active debris remediation, and investigates if such electrostatic tractors are suitable for small asteroids being considered for asteroid retrieval missions. Active charge transfer is used to impart arresting electrostatic torques on such objects, given that they are sufficiently non-spherical. The concept of touchless electrostatic detumbling of space debris is outlined through analysis and experiments and is shown to hold great promise to arrest the rotation within days to weeks. However, even conservatively optimistic simulations of small asteroid detumbling scenarios indicate that such a method could take over a year to arrest the asteroid rotation. The numerical debris detumbling simulation includes a charge transfer model in a space environment, and illustrates how a conducting rocket body could be despun without physical contact.
Neurosurgery certification in member societies of the WFNS: Europe.

Objective To objectively compare the complexity and diversity of the certification process in Neurological Surgery in European member societies of the World Federation of Neurosurgical Societies. Materials and Methods The attention of this study centers on Europe. We provide here a subgroup analysis based on the responses provided to a 13-item survey. The data received were analyzed and three regional complexity scores (RCS) were designed. To compare national board experience as well as eligibility requirements to access the certification process and obligatory nature of the examinations, a RCS Organizational score was created (RCS-O, 20 points maximum). To analyze the complexity of the examination a RCS Components score was designed (RCS-C, 20 points maximum). The sum of both is presented in a Global RCS score (RCS-G). In addition, a descriptive summary of the certification process per responding society is also provided. Results and Conclusions Based on the data provided by our RCS system, the highest RCS-G was obtained by the United Kingdom (19/40 points) followed by European Association of Neurosurgical Societies, Poland, and Sweden (16/40 points each), Portugal (15/40 points), and Switzerland (14/40 points). The experience from these leading countries should be of value to all countries of the European Union. Peer-Review Article
GPU Accelerated Chemical Similarity Calculation for Compound Library Comparison

Chemical similarity calculation plays an important role in compound library design, virtual screening, and "lead" optimization. In this manuscript, we present a novel GPU-accelerated algorithm for all-vs-all Tanimoto matrix calculation and nearest neighbor search. By taking advantage of multicore GPU architecture and CUDA parallel programming technology, the algorithm is up to 39 times superior to the existing commercial software that runs on CPUs. Because of the utilization of intrinsic GPU instructions, this approach is nearly 10 times faster than existing GPU-accelerated sparse vector algorithm, when Unity fingerprints are used for Tanimoto calculation. The GPU program that implements this new method takes about 20 min to complete the calculation of Tanimoto coefficients between 32 M PubChem compounds and 10K Active Probes compounds, i.e., 324G Tanimoto coefficients, on a 128-CUDA-core GPU.
Enhancement of sterol synthesis by the monoterpene perillyl alcohol is unaffected by competitive 3-hydroxy-3-methylglutaryl-CoA reductase inhibition

Monoterpenes such as limonene and perillyl alcohol (PA) are currently under investigation for their chemotherapeutic properties which have been tied to their ability to affect protein isoprenylation. Because PA affects the synthesis of isoprenoids’ such as ubiquinone’ and cholesterol is the end product of the synthetic pathway from which this isoprenoid pathway branches’ we investigated the effects of this compound upon cholesterol metabolism in the colonic adenocarcinoma cell line SW480. PA (1 mM) inhibited incorporation of 14C-mevalonate into 21–26 kDa proteins by 25% in SW480 cells. Cholesterol (CH) biosynthesis was assessed by measuring the incorporation of 14C-acetate and 14C-mevalonate into 27-carbon-sterols. Cells treated with PA (1 mM) exhibited a fourfold increase in the incorporation of 14C-acetate but not 14C-mevalonate into cholesterol. Mevinolin (lovastatin)’ an inhibitor of 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase’ at 2 μM concentration’ inhibited CH synthesis from 14C-acetate by 80%. Surprisingly’ concurrent addition of mevinolin and PA did not significantly alter the stimulatory effects of PA. As observed differences in 14C-acetate and 14C-mevalonate precursor labeling could indicate PA affects early pathway events’ the effects of this monoterpene on HMG-CoA reductase activity were evaluated. Unexpectedly’ 1 mM PA did not stimulate activity of this enzyme. Consistent with its action as a reversibly bound inhibitor’ in washed microsomes’ 2 μM mevinolin pretreatment increased reductase protein expression causing a 12.7 (±2.4)-fold compensatory HMG-CoA reductase activity increase; concurrent treatment with 1 mM PA attenuated this to a 5.3 (±0.03)-fold increase. Gas chromatographic analysis confirmed CH was the major lipid present in the measured thin-layer chromatography spot. Since 14C-acetate incorporation into free fatty acid and phospholipid pools was not significantly affected by PA treatment’ nonspecific changes in whole acetate pool sizes were not indicated. Because increases in endogenous CH synthesis should result in compensatory changes in exogenous sterol utilization’ the effects of PA upon low density lipoprotein (LDL) receptor activity were evaluated. Consistent with the observed increases in CH synthesis’ 1 mM PA decreased 125I-LDL internalization to 50% of the fetal bovine serum control; concurrent addition of 2 μM mevinolin attenuated this effect to a reduction of 80% of the control value. Data suggest that in certain colonic tumor cells PA strongly affects cholesterol metabolism via a mechanism of action that is insensitive to the HMG-CoA reductase inhibitor mevinolin.
Dielectric tracking in liquid helium

Measurements of the breakdown field of typical magnet insulators of thickness < 0.7 mm, under conditions in which the breakdown is by surface tracking across the narrow dimension, yield values which are characteristic of helium gas at the saturated vapour pressure for temperatures above the lambda point. Below the λ point, the breakdown field rises again, but does not attain its 4.2 K value. Measurements also show that the tracking strength of a surface badly contaminated with metal particles is not appreciably less than that for a clean surface.
Carbon Atom, Dimer and Trimer Chemistry on Diamond Surfaces from Molecular Dynamics Simulations

Spectroscopic studies of various atmospheres appearing in diamond film synthesis suggest evidence for carbon atoms, dimers, or trimers. Molecular dynamics simulations with the Brenner hydrocarbon potential are being used to investigate the elementary reactions of these species on a hydrogen-terminated diamond (111) surface. In principle these types of simulations can be extended to simulations of growth morphologies, in the 1-2 monolayer regime presently.
DISC ELECTROPHORESIS ANALYSIS OF SIALIDASE FROM INFLUENZA VIRUS.

Summary Disc electrophoresis per se and in combination with immunodiffusion procedures facilitated the characterization of sialidase. Irrespective of the isolation procedures, sialidase of influenza virus (A2 Japan 305/57) appeared to be electrophoretically heterogeneous. This was indicated by disc electrophoresis and analysis of eluates in the “segmentation experiments” and by the “disc immunodiffusion” techniques. It was further noted that “purified” sialidase in phosphate buffer stored at 0 to 5°C. dissociated and simultaneously lost 90 per cent of its enzyme activity. The procedures described above proved valuable, particularly when analyzing limited quantities of material.
Effect of oxypurinol on cyclosporine toxicity in cultured EA, LLC-PK1 and MDCK cells

It has been proposed that cyclosporin (CsA) toxicity may in part be due to the action of oxygen-based free radicals. We compared the response of cultured endothelial (EA) and epithelial (LLC-PK1 and MDCK) cells to CsA, 250 or 1000 ng/mL for 24 or 72 h, with or without the xanthine oxidase inhibitor oxypurinol (Oxy), 10 mg/mL. CsA-induced alterations were seen on phase contrast and electron microscopy. In EA cells, swollen mitochondria and large cytoplasmic vacuoles surrounded by a thin membrane containing ribosomes were present at the periphery of the cell. In LLC-PK1 cells no vacuoles were present while in MDCK cells, the vacuoles were smaller and more centrally located. In both epithelial cell lines, mitochondria were distorted with loss of cristae. In all three cell lines, CsA depressed cell counts and decreased 3H-thymidine incorporation. Also, LDH release was accelerated. The addition of Oxy minimized the morphologic effect of CsA on all three cell lines with the effect more apparent in EA cells. The CsA-induced reduction of cell replication and increase in LDH release were also attenuated by Oxy. These results support the notion that the peroxidative properties of CsA may be responsible in part for CsA-induced nephrotoxicity.
The effect of imidoesters, fluorodinitrobenzene and trinitrobenzenesulfonate on ion transport in human erythrocytes

Abstract Several amino-reactive chemical probes which differ in hydrophobicity and charge and in their ability to penetrate the red cell membrane were tested for their ability to modify K + leak and inorganic phosphate (Pi) leak in intact human red cells. Methyl picolinimidate (MP), ethyl acetimidate (EA), methyl acetimidate (MA) are hydrophilic penetrating probes whereas isethionylacetimidate (IA) is a hydrophilic non-penetrating probe. The order of their effectiveness in inhibiting Pi leak was found to be MP>EA>MA>IA. This order is in decreasing hydrophobicity and suggests that some penetration into the bilayer or into hydrophobic domains of the anion transport protein is required to modify an amino group required for Pi permeability through the membrane. These imidoesters have little or no effect on K + leak in the red cell. Trinitrobenzenesulfonate (TNBS) a relatively non-penetrating hydrophobic anionic probe and fluorodinitrobenzene (FDNB) a penetrating hydrophobic neutral probe have markedly different effects on K + and Pi leak. TNBS has little effect on K + leak but markedly inhibits Pi leak. The effect of TNBS on Pi leak is not blocked by prior treatment with IA suggesting that these probes sense different populations of amino groups in the membrane. FDNB nearly completely blocks Pi leak and markedly increases K + leak. The results with TNBS and FDNB indicate an asymmetric arrangement of amino groups on the red cell membrane. Certain amino groups on the outer surface of the membrane regulate Pi permeability whereas certain amino groups on the inner surface of the membrane regulate K + permeabilty. The data also suggest that these amino groups are in a hydrophobic domain.
Editorial: gene–environment interplay in child psychology and psychiatry – challenges and ways forward

This special issue in the Journal of Child Psychology and Psychiatry presents several invited articles examining gene-environment interplay in child development and psychopathology. Models of gene-environment interplay have been exhaustively discussed in the literature, including an important contribution by Rutter, Moffitt and Caspi (2006) published in this journal.
Peer-Mediated Teaching and Students With Learning Disabilities

Peer-mediated instruction holds particular promise as an effective educational strategy for children with learning disabilities. When properly implemented, peer-mediated instructional approaches pe...
The effect of tanning agents on the permeability of the toad bladder to water and solutes

Previous studies with phloretin have shown that the movement of urea and other solutes across the toad bladder can be inhitited with no effect on osmotic water flow, active sodium transport, or the movement of ethanol and ethylene glycol. These findings have suggested that a vasopressin-sensitive carrier is involved in the transport of solutes such as urea across the luminal membrane of the epithelial cell. The present paper describes the effect of two agents other than phloretin: tannic acid and chromate, on water and solute movement across the bladder. The pattern of action of these two agents resembles that of phloretin, and supports our earlier findings of the independence of solute and water movement. The effect of chromate on urea movement is seen only in the presence of vasopressin, and only if chromate is added prior to vasopressin. Chromate also proves to be an irreversible inhibitor of urea movement. The implications of these findings are discussed. In view of the known interactions of both agents with proteins, it is suggested that carrier-mediated transport of urea proceeds across a protein component of the membrane.
δ-aminolevulinate synthase activity in the Harderian glands of male and female Golden Hamsters

Abstract 1. 1. δ-Aminolevulinate (AlA) synthase activity was determined in the Harderian glands of male and female Golden Hamsters. 2. 2. The enzyme activity was higher in the female gland than in the male gland. 3. 3. The data suggest that the higher enzyme activity is, at least partly, related to the higher porphyrin content in the female gland. 4. 4. This enzyme activity has not been reported in the male gland previously.
Negative effects of habitat drying and prior exploitation on the detritus resource in an ephemeral aquatic habitat.

Ephemeral aquatic habitats are characterized by cycles of drying and subsequent inundation, and by production of sequential non-overlapping cohorts of organisms. Both processes may alter the quantity or quality of resources, and may therefore affect survival and development of cohorts that subsequently colonize ephemeral habitats. We examined these effects of habitat drying and non-overlapping cohorts on experimental cohorts of the tree hole mosquito Aedes triseriatus, testing specifically whether the value of leaf litter as a food resource is altered by cycles of inundation and drying, or by exploitation by a prior non-overlapping cohort. We created four treatments of leaf litter: (1) no prior cohort, continuously wet; (2) no prior cohort, one␣wet/dry cycle; (3) prior cohort, continuously wet, and (4) prior cohort, one wet/dry cycle, and tested for effects on individual fitness components (survivorship, mean dry mass at, and median days to eclosion) and on population growth (estimated finite rate of increase –λ′). Both resource drying and the presence of a prior cohort negatively affected individual fitness components in tires, increasing days to eclosion, and decreasing mean dry mass at eclosion for both sexes. Resource drying also negatively affected estimated rates of increase (λ′) in tree holes. A prior cohort had no significant effects on λ′. These results indicate that intraspecific interactions among mosquito larvae may include amensalistic effects of earlier, non-overlapping cohorts, and that resource drying reduces resource quality. The latter effect indicates that enhanced production of A. triseriatus from recently filled containers is not due to resource drying per se, and may result from more complex community-level effects of habitat drying. Extreme cycles of drying and inundation seem likely to increase intraspecific resource competition among drought-adapted species like A. triseriatus.
INFLUENCE OF PLANT SIZE AND CLIMATIC VARIABILITY ON THE FLORAL BIOLOGY OF FOUQUIERIA SPLENDENS(OCOTILLO)

ABSTRACT The floral biology of Fouquieria splendens (Fouquieriaceae), a drought-deciduous shrub with wandlike branches, was studied in the northern Sonoran Desert. Two different measures of plant size, number of branches long enough to flower (>1 m in length) and actual number of reproductive branches, were used to examine the effect of plant size on reproductive output and floral display. Number of flowers and fruits increased with either measure of plant size. Annual flower production ranged from 190 to 6465 per plant and averaged 2553. Annual fruit production ranged from 9 to 1760 per plant and averaged 390. Because some branches long enough to flower did not do so, number of reproductive branches was a stronger predictor of flower production than number of branches > 1 m long. Inflorescence size (mean number of flowers per panicle) was not significantly related to plant size (number of flowering branches) in 2002 or 2003; in fact, the range in inflorescence size on certain individual plants was about ...
Endogenous particulate inhibitor of microtubule assembly in developing mammalian brain.

Abstract Microtubule assembly in vitro was inhibited by an endogenous particulate fraction of mouse brain. This inhibitory activity was isolated from the supernatant obtained when assembled microtubules were separated from soluble tubulin by centrifugation of crude brain extracts in glycerol medium at room temperature. The inhibitory fraction could be pelleted upon dilution of glycerol. The endogenous particulate fraction inhibited microtubule assembly in a concentration-dependent manner, and in a manner similar to soluble yeast RNA and other polyanions. The factor was sensitive to RNase and heat. The amount of this factor, relative to tubulin levels, varied with neonatal animal age in a manner which appears to explain our earlier observation ( J. A. Koehn, and R. W. Olsen, 1978 , Arch. Biochem. Biophys. , 186 , 114–120) of an age variation in tubulin assembly competence. Variations in the assembly properties of tubulin itself did not appear to explain these age differences. Whereas extracts obtained at room temperature in microtubule-stabilizing medium containing glycerol appeared to have a greater fraction of assembled tubulin in neonatal brain than in adult, soluble extracts obtained at 0 °C without glycerol showed no age-dependent differences in their overall assembly competency in vitro . The action of this RNA-containing, heat-sensitive particulate factor on microtubule assembly may reflect an in vivo regulatory mechanism.
Influence of Preswirl on Rotordynamic Characteristics of Labyrinth Seals

Labyrinth seals are widely used in turbomachines and can have a significant influence on the stability of the rotor bearing system. The working fluid usually has a circumferential velocity component before entering the seal. The average fluid circumferential velocity in the upstream region prior to the first tooth divided by the shaft synchronous surface velocity is defined as the preswirl rate. It has been observed that the preswirl rate is an important factor affecting the rotordynamic coefficients of labyrinth seals, thus affecting the stability of the rotor. Therefore, it is of interest to investigate the exact relationship between the preswirl rate and the seal's rotordynamic coefficients. In this article, the flow in a typical compressor eye seal is simulated in 3D models with eccentricity ranging from 0.1 to 0.7 using ANSYS-CFX. The rotordynamic coefficients of the seal at different preswirl rates and eccentricities are calculated. The case with no preswirl and eccentricity of 0.1 are compared to p...
Particulate and soluble hexavalent chromium are cytotoxic and genotoxic to human lung epithelial cells

Abstract Particulate hexavalent chromium (Cr(VI)) is a well-established human lung carcinogen. It is currently a major public health concern, there is widespread exposure to it in occupational settings and to the general public. However, despite the potential widespread exposure and the fact that the lung is its target organ, few studies have considered the toxic effects of particulate Cr(VI) in human lung cells. Accordingly, we used lead chromate as a model particulate Cr(VI) compound and determined its cytotoxicity and genotoxicity in cultured human bronchial epithelial cells, using BEP2D cells as a model cell line. We found that lead chromate induced concentration-dependent cytotoxicity in BEP2D cells after a 24 h exposure. Specifically, the relative survival was 78, 59, 53, 46 and 0% after exposure to 0.5, 1, 5, 10 and 50 μg/cm 2 lead chromate, respectively. Similarly, the amount of chromosome damage increased with concentration after 24 h exposure to lead chromate. Specifically, 0.5, 1, 5 and 10 μg/cm 2 damaged 10, 13, 20 and 28% of metaphase cells with the total amount of damage reaching 11, 15, 24 and 36 aberrations per 100 metaphases, respectively. Lead chromate (50 μg/cm 2 lead chromate) induced profound cell cycle delay and no metaphases were found. In addition we investigated the effects of soluble hexavalent chromium, sodium chromate, in this cell line. We found that 1, 2.5, 5 and 10 μM sodium chromate induced 66, 35, 0 and 0% relative survival, respectively. The amount of chromosome damage increased with concentration after 24 h exposure to sodium chromate. Specifically, 1, 2.5 and 5 μM damaged 25, 34 and 41% of metaphase cells with the total amount of damage reaching 33, 59 and 70 aberrations per 100 metaphases, respectively. Ten micromolar sodium chromate induced profound cell cycle delay and no metaphases were found. Overall the data clearly indicate that hexavalent Cr(VI) is cytotoxic and genotoxic to human lung epithelial cells.
Electrophoretic mobility and primary electroviscous effect of dilute "hard" prolate ellipsoids.

Abstract Electrophoretic mobilities and primary electroviscous coefficients are determined for “hard” prolate ellipsoids of axial ratio less than or equal to 4 in KCl, NaCl, and Tris–glycine salt solutions. Account is taken of the steady state distortion of the ion atmosphere around the ellipsoid by numerical solution of the coupled Poisson, low-Reynolds-number Navier–Stokes, and ion transport equations. This is accomplished by a boundary element procedure. Results are presented as ratios of mobilities and primary electroviscous coefficients of ellipsoids to those of corresponding spheres. It is shown that the electrophoretic mobility of an ellipsoid is very similar to that of a sphere under similar conditions of size, ionic strength, salt type, and zeta potential. Other factors being equal, shape has little effect on electrophoretic mobility. For the primary electroviscous coefficient, on the other hand, there is a substantial shape effect. It is argued that the complementary techniques of electrophoresis and viscosity together provide an effective means of studying the size, charge, and shape of macroions and colloidal particles.
Misunderstanding Prescription Labels: The Genie Is Out of the Bottle

The U.S. health care system largely operates under the assumption that all patients have high English-language literacy skills. In fact, many do not. In this issue, Davis and coworkers carefully sh...
Nursing workforce issues: an update, implications, and strategies for pediatric nurses.

HIS CHILD HEALTH Policy Columnarticle will present some of the preliminary findings from the 2000 National Sample Survey of Registered Nurses and a discussion of the implications of these findings as they pertain to the emerging nursing shortage in the United States. In addition, two new federal bills in the 107th Congress proposed to address the nation’s nursing workforce crisis, will also be presented. Strategies and recommendations for pediatric nurses to assist in the recruitment and retention of individuals into the nursing profession and in particular the specialty of pediatric nursing will be discussed.
Low-energy cross sections for 7Li(p, α)4He and 6Li(p, α)3He

Reaction cross sections for ^6Li(p, α)^3He and ^7Li(p, α)^4He were obtained using lithium beams and a CH^4 gas target at equivalent proton energies between 130keV and 560 keV. The Rutherford scattering of lithium on carbon was used as a cross-section standard. For ^6Li + p, an extrapolation of the cross section to the energy region of astrophysical interest is given.