cssi/SciSciGPT-SciSciNet huggingface dataset:
"The umbilical fat sign": an important and consistent landmark during single port/incision laparoscopic surgery and standard laparoscopy.

Introduction During single port laparoscopic surgery (SPLS), access is obtained through the umbilicus and the scar is hidden within the scar of the umbilicus for providing good cosmesis. It is essential that the incision be well planned so as to get the maximum exposure through the umbilical incision. The umbilical fat sign is an important landmark to achieve this. Purpose The aim of this study is to retrospectively review importance of the umbilical fat sign as a landmark for peritoneal access during SPLS in children. Method A retrospective chart review of 57 children (33 males and 24 females) who underwent single port access surgery at Texas Children's Hospital from April 2009 to December 2010 was conducted. The median age of the patients was 10.8 years, ranging from 4 to 17 years. Technique The limits of the umbilicus were marked using a marking pen. A vertical incision is made through the center of the umbilical scar. It is of vital importance to maintain the incision in the exact center of the scar tissue. Skiving away from the center makes the entry in the peritoneal cavity harder and prolongs peritoneal access time. During all the single port cases, we have done so far we have noted that if we are in the center of the scar then we always see a blob of fat (”umbilical fat” sign) in the center. If we use a probe or grooved director through this fat direct access is obtained in the peritoneal cavity. Incision can then be extended on both sides and be kept to the limits of the umbilical ring. Peritoneal access can be obtained in 1 to 2 minutes using this approach. Umbilical reconstruction is the best performed with this approach. Results One child developed signs of wound infection and was treated successfully with antibiotics for 5 days. Scars healed well in all cases with no wound dehiscence. No umbilical scars were visible at follow-up (3 to 4 weeks postoperatively). Conclusion Umbilical fat sign is an important landmark for surgeons during SPLS for direct and quick peritoneal access and better reconstruction of the umbilicus.
Optical access couplers and a comparison of multiterminal fiber communication systems

Optical T and multiple T access couplers designed for tapped trunk line multiterminal communication systems that use bundles of multimode fibers as the transmission media have been investigated. The particular coupler designs tested used bent Pyrex rods for bifurcation and scrambling. Coupler throughput losses (not counting packing fraction losses) are 1.5-2.5 dB. The bent rod optical T and multiple T access couplers must be used with high N.A., low packing fraction loss fibers. To avoid the use of a repeater a multiple T or star configuration must be used in a system comprising ten or more terminals.
A new solution procedure for application of energy-conserving algorithms to general constitutive models in nonlinear elastodynamics

Abstract This paper develops a novel solution strategy for temporal discretization of initial value problems in nonlinear elastodynamics, enabling exact energy and momentum conservation for a spatially discretized problem. This new energy–momentum algorithm fits into the general framework established by Simo and Tarnow [Z. Angew Math. Phys. 43 (1992) 757]. However, in contrast to the presentation given in that reference, the current approach extends the critical stress update formula to encompass generic stored energy functions for the hyperelastic continuum, in a manner which also allows for quadratically convergent Newton–Raphson solution of the nonlinear algorithmic equations. Numerical examples using a Neo–Hookean material model are given to illustrate the excellent performance of the proposed scheme. Not only is the new algorithm guaranteed to be second-order accurate and unconditionally stable in the fully nonlinear regime (as are other energy–momentum strategies), but also the approach advocated is demonstrated to be more robust and versatile than its predecessors.
Patterns of informal care among Puerto Rican, African American, and white stroke survivors

Background. There has been an increase in the number of non-institutionalized stroke survivors over the past few decades leading to larger numbers of family caregivers. Less is known about the patterns of informal caregiving within racially and ethnically diverse families even though there is greater post-stroke morbidity and mortality for these groups. Research aims. The purpose of our research is to examine the informal caregiving networks of white, African American, and Puerto Rican caregivers. Methodology. We examine data collected from 118 stroke survivors and caregivers to explore the dynamics of caregiving. Data are drawn from a diverse group of whites, African Americans, and Puerto Ricans living on the US Mainland and Puerto Rico at three different time points over the course of 12 months. Analysis. We examine the size, stability, change, and family dynamics of informal caregiving networks. Findings and implications. We find that whites, African Americans, and Puerto Ricans each have differing car...
Molecular and electronic structure of benzeneselenenyl molecules and cations

Molecular and electronic structures of a select group of molecules and cations, including benzeneselenenyl chloride, benzeneselenenyl bromide, and benzeneselenol have been studied using ab initio calculations at the Hartree–Fock and MP2 levels of theory. Very few experimental data are available for this class of compounds. The properties and structures of these molecules are compared. © John Wiley & Sons, Inc.
The Training of Class Inclusion and English Language Skills in Young Latino Children.

Abstract Using a multiple baseline design, four 6-year-old Latino school children were trained on class inclusion and English language skills over approximately five months. Class inclusion tasks consisted of standard Piagetian two-subclass items as well as new and more challenging three- and four-subclass tasks pertaining to two superordinate categories. Counting, feedback and various verbal reinforcers were used as part of the class inclusion training. English language skills training served as an alternative form of instruction that was of benefit in its own right and also made a variant of the multiple baseline approach possible. Post-intervention gains on the two domains were significant and proved stable over at least four-and-a-half months.
Effect of Microbial Activity on Trace Element Release from Sewage Sludge

The microbial role in mobilization of trace elements from land-applied wastewater sludge is not well-defined. Our study examined the leachability of trace elements (Cd, Cr, Cu, Mo, Ni, P, Pb, S, and Zn) from dewatered sludge as affected by treatments designed to alter microbial activity. Different levels of microbial activity were achieved by incubating sludge columns at 4, 16, 28, and 37 °C and by the addition of AgNO3 biocide at each temperature. Columns (with inert glass bead support beds) were subjected to six consecutive incubation−leaching cycles, each consisting of 7.3-d incubation followed by 16-h leaching with synthetic acid rain. Glucose mineralization tests were used to assess overall microbial activity. Significant acidification and trace element leaching occurred when conditions favored microbial activity (16 and 28 °C). Extent of mobilization was element-specific with Zn, Ni, and Cu showing the greatest mobilization (99, 67, and 57%, respectively). Mobilization was reduced but still substant...
Association of Obesity With Inflammation and Pain After Total Hip Arthroplasty

Background The prevalence of obesity is increasing, and obesity often leads to degenerative joint disease requiring total hip arthroplasty (THA). Obesity is a proinflammatory state associated with an increase in chronic, low-grade inflammatory response. As such, it may augment the postoperative inflammatory response, which has been associated with postoperative pain and complications.
Hard copy output devices

Abstract This paper discusses the selection of devices for producing hard copy from interactive graphics systems. A brief description of the various copying techniques is given. The various types of equipment commercially available on the market will be categorized to assist in selection along criteria of equipment cost, running cost, speed and resolution.
Auger resonance decay process in Ar 2p shell excitation and ionization

The production and subsequent autoionization of the ${\mathrm{Ar}}^{+}{(}^{1}{D}_{2}{)6d}^{\ensuremath{'}}$ satellite state that is formed either by shake-up or recapture during the Auger decay of a $2p$ vacancy in Ar has been studied by photoelectron spectroscopy in the energy region from 243 to 256 eV. The creation of near zero energy electrons below and immediately above the $\mathrm{Ar} 2p$ ionization threshold is discussed. Some ambiguous points in previous studies are clarified.
The Myth of Gender Cultures: Similarities Outweigh Differences in Men's and Women's Provision of and Responses to Supportive Communication

Michaud and Warner (1997) and Basow and Rubenfeld (2003) recently reported studies of gender differences in “troubles talk” that allegedly provide support for the different cultures thesis, that is, the notion that men and women communicate in such different ways that they should be regarded as members of different communication cultures or speech communities. In this article, we identify several limitations in these two studies that, collectively, have the effect of casting doubt on their conclusions. We then report three studies that show that men and women provide and respond to supportive messages (“troubles talk”) in ways that are much more similar than different. The current findings, in conjunction with other recent findings, suggest that the different cultures thesis is a myth that should be discarded.
Novel guest-layer behavior of mercury titanium disulfide intercalates

Electron diffraction has been used to observe in situ HgxTiS2 (1.24 > x ≥ 0.00) guest-layer structural behavior as a function of temperature. At low temperature (−170 °C), Hg forms well-ordered inc...
MO-D-AUD A-01: Summarizing Our Knowledge of Normal Tissue Tolerances: The Progress and Future Directions of QUANTEC

AAPM and ASTRO are jointly funding an effort, called QUANTEC (QUAntitative Normal TissuE models in the Clinic), which aims to summarize our knowledge of dose volume dependencies of the normal tissue complications of external beam radiotherapy, and where possible, give quantitative guidance for clinical treatment planning and optimization. Following the initial QUANTEC meeting in Madison in October 2007, attended by approximately 75 physicists, MDs and bio‐statisticians, an upcoming special issue of the Red Journal is in preparation, which will include articles on complications in some 18 normal organs. For each of these organs, extensive literature reviews were undertaken, and clinically significant endpoints identified. Where possible, results were synthesized and compared, guided by the quality and levels of evidence of the studies. Criteria included prospective or retrospective nature, statistical power, presence and reliability of quantitative data on dose‐volume effects. Other clinical factors influencing complications were assessed, such as the influence of chemotherapy, fraction size and pre‐existing medical conditions. Special emphasis was placed on attempting to provide quantitative guidelines for clinical treatment planning. This talk will convey the mission, and give selected examples of the achievements of QUANTEC. It will outline the current state of our knowledge, and highlight areas where opportunities exist to improve our understanding. Educational Objectives: 1. To understand the current state of knowledge of dose volume dependencies of complication probabilities. 2. To understand the criteria and methods used by QUANTEC in selecting and summarizing this knowledge. 3. To understand the shortcomings of the clinical data as it currently exists. 4. To understand the possible strategies for overcoming these shortcomings.
A two-dimensional comprehensive hydrodynamic model for femtosecond laser pulse interaction with metals

Femtosecond laser–metal interaction in air and the resultant early plasma evolution are investigated by a two-dimensional comprehensive hydrodynamic model in this paper. The model comprises a two-temperature model and a hydrodynamic model supplemented with a quotidian equation of state model, considering the relevant multiphysical phenomena during the laser–metal interaction. The experimental measurements for plasma expansion were carried out to validate the simulation results, using a shadowgraph technique and direct fluorescence measurement. The evolution of both the early plasma and plume plasma is investigated by the model. The early plasma is proved to be generated by electron emission and ambient gas ionization and splits into several portions during its expansion due to different mechanisms. The plume plasma comes from the target material ejection. The photoelectric emission is revealed to be the dominant electron emission mechanism at high laser intensities, while thermal emission is more important at low laser intensities. The electron emission process and early stage plasma are critical to ultrashort laser–metal interaction, especially at high laser intensities. Without considering this, the electron temperature can be overestimated by as much as 70%.
The effects of amphetamine isomers on neuromuscular transmission.

Abstract The effects of (+)- and (−)-amphetamine on neuromuscular transmission were evaluated by monitoring twitch tension elicited by direct and/or indirect stimulation of the isolated rat phrenic nerve-diaphragm preparation. Low concentrations of these isomers (1.35−2.7 × 10−4 m ) facilitated twitch, while higher concentrations (4.05−8.1 × 10−4 m ) caused dose-dependent blockade in nerve-stimulated preparations. Tachyphylaxis developed to the facilitatory effects of (+)-amphetamine on twitch tension; a progressive enhancement in the rate and magnitude of depression was observed with successive doses. Tachyphylaxis to facilitated twitch did not occur with up to eight successive additions of (−)-amphetamine. Both amphetamine isomers (2.7−8.1 × 10−4 m ) enhanced twitch tension (14−74%) directly elicited in a dose-related manner. A reduction in bath temperature from 37 to 25° C slowed the rate of amphetamine blockade, as did a 1.6-fold increase in K+ (to 7.5 m m ). Amphetamine blockade was enhanced by the absence of Ca2+ or 3-fold elevations in the bath concentrations of K+ and Mg2+. (+)-Tubocurarine or succinylcholine in combination with amphetamine produced mutually enhanced blockade of twitch. These results suggest that amphetamine-induced muscle weakness in high doses and enhancement in physical endurance and in performance in moderate doses may result, at least in part, from a peripheral component. Amphetamine's actions on neuromuscular transmission are complex and may be the consequence of interactions with adrenergic and/or cholinergic systems.
Spread of barley yellow dwarf virus and relative importance of local aphid vectors in central Washington

SUMMARY Data from bioassays of field collected aphids, barley indicator plants exposed to natural conditions, and various types of aphid traps were used to describe the spread of barley yellow dwarf virus (BYDV) in wheat and barley near Prosser, Washington. Bioassays were also used to assess the relative importance of local vector species. Of alate aphids collected from grain in the 1982 and 1983 fall migration seasons, 3.4–14–5% transmitted BYDV. Data from concurrent and post-migration assays of resident aphids (apterae and nymphs) reflected an increase in the proportion of infected plants in the field. Maximum increase in the percentage of viruliferous aphids occurred in late November and December of 1982 and November of 1983. The 1982 increase occurred after aphid flights had ceased for the year, suggesting active secondary spread. Collections in pitfall traps and infected trap plants from November to February confirmed aphid activity and virus spread. Rhopalosiphum padi was the most important vector in central Washington in 1982 and 1983 because of its abundance and relative BYDV transmission efficiency. Metopolophium dirhodum was more winter-hardy than R. padi and equal to R. padi in its efficiency as a vector; however, it was not as abundant as R. padi except during the mild winter of 1982–83, when it was a major contributor to secondary spread. Sitobion avenae may be important in years when it is abundant, but it was only a quarter as efficient as R. padi. Rhopalosiphum maidis was a much less efficient vector than R. padi and it only reached high populations in late autumn barley.
Carbon Nanotube Linear Bearing Nanoswitches

We exploit the remarkable low-friction bearing capabilities of multiwalled carbon nanotubes (MWNTs) to realize nanoelectromechanical switches. Our switches consist of two open-ended MWNT segments separated by a nanometer-scale gap. Switching occurs through electrostatically actuated sliding of the inner nanotube shells to close the gap, producing a conducting ON state. For double-walled nanotubes in particular, a gate voltage can restore the insulating OFF state. Acting as a nonvolatile memory element capable of several switching cycles, our devices are straightforward to implement, self-aligned, and do not require complex fabrication or geometries, allowing for convenient scalability.
Natural convection heat transfer of nanofluids in a vertical cavity: Effects of non-uniform particle diameter and temperature on thermal conductivity

Abstract This paper analyzes the heat transfer and fluid flow of natural convection in a cavity filled with Al 2 O 3 /water nanofluid that operates under differentially heated walls. The Navier–Stokes and energy equations are solved numerically, coupling Xu’s model ( Xu et al., 2006 ) for calculating the effective thermal conductivity and Jang’s model ( Jang et al., 2007 ) for determining the effective dynamic viscosity, with the slip mechanism in nanofluids. The heat transfer rates are examined for parameters of non-uniform nanoparticle size, mean nanoparticle diameter, nanoparticle volume fraction, Prandtl number, and Grashof number. Enhanced and mitigated heat transfer effects due to the presence of nanoparticles are identified and highlighted. Based on these insights, we determine the impact of fluid temperature on the heat transfer of nanofluids. Decreasing the Prandtl number results in amplifying the effects of nanoparticles due to increased effective thermal diffusivity. The results highlight the range where the heat transfer uncertainties can be affected by the size of the nanoparticles.
PAH emissions from high-temperature oxidation of vaporized anthracene

Abstract The presence of polycyclic aromatic hydrocarbons/compounds (PAH/PAC) in the exhaust of combustion equipment as well as their growth to soot particles depends on the balance of formation and depletion reaction pathways. Detailed understanding of PAH oxidation is necessary for a correct quantitative description of combustion processes. This study focuses on the high-temperature oxidation of anthracene, a 3-ring PAH, by molecular oxygen. By reacting this already formed PAH, under non-sooting conditions, its oxidative depletion processes were isolated from its formation processes, as well as from soot formation pathways. Anthracene powder, fluidized in nitrogen, was introduced into a two-stage electrically heated laminar-flow drop-tube furnace. In the first stage, kept at 900 °C, anthracene was vaporized. Thereafter, upon mixing with preheated oxygen-containing gases in a venturi, gaseous anthracene was oxidized in the second furnace at oxygen mole fractions of 1–5% and gas temperatures of 950–1050 °C. Gas temperature and velocity profiles in the furnaces, as well as anthracene particle vaporization trajectories were obtained with a computational fluid dynamics code. Sampling, followed by chemical analysis, was conducted at three locations within the oxidizing furnace. Trends with residence time show increasing CO and CO2 yields in the furnace and gradually decreasing O2. CO increased with higher oxidizing temperatures and oxygen concentrations. Acetylene was the most abundant light hydrocarbon, followed by methane, ethylene, benzene, propylene and ethyl acetylene. Prevalent PAC included fluorene-9-one, 9,10-anthracenodione, biphenylene, dibenzofuran, fluorene, indene, naphthalene, anthrone, xanthone and 2-naphthalenecarboxaldehyde. Most species’ yields increased with rising oxidation temperatures. A global anthracene reaction rate with oxygen was deduced, and an activation energy of 71 kJ/mol was calculated. An anthracene oxidation reaction scheme was proposed.
Aggregation Dynamics for Two Particles during Electrophoretic Deposition under Steady Fields

The motion of particles deposited on an electrode by electrophoresis is governed by electrokinetics, electrohydrodynamics, and Brownian diffusion. Under a dc electric field, the particles attract e...
A miniaturized neuroprosthesis suitable for implantation into the brain

This paper presents current research on a miniaturized neuroprosthesis suitable for implantation into the brain. The prosthesis is a heterogeneous integration of a 100-element microelectromechanical system (MEMS) electrode array, front-end complementary metal-oxide-semiconductor (CMOS) integrated circuit for neural signal preamplification, filtering, multiplexing and analog-to-digital conversion, and a second CMOS integrated circuit for wireless transmission of neural data and conditioning of wireless power. The prosthesis is intended for applications where neural signals are processed and decoded to permit the control of artificial or paralyzed limbs. This research, if successful, will allow implantation of the electronics into the brain, or subcutaneously on the skull, and eliminate all external signal and power wiring. The neuroprosthetic system design has strict size and power constraints with each of the front-end preamplifier channels fitting within the 400 /spl times/ 400-/spl mu/m pitch of the 100-element MEMS electrode array and power dissipation resulting in less than a 1/spl deg/C temperature rise for the surrounding brain tissue. We describe the measured performance of initial micropower low-noise CMOS preamplifiers for the neuroprosthetic.
Effect of microstructure on the uniaxial tensile deformation behavior of Mg–4Y–3RE alloy

Abstract This paper reports microstructure–mechanical property correlations for a Mg–4Y–3RE (WE43) alloy. Friction stir (FS) processing was employed to modify the microstructure of hot-rolled (as-received) WE43 alloy. The grain size decreased from 10 to 300 µm in as-received condition to an average of 3.1±0.4 µm in FS processed condition. The alloy in AR condition contained globular, acicular, and rectangular (cuboidal) shaped precipitates located at twin boundaries, grain boundaries, and intragranular regions, along with fine scale honeycomb network of intragranular β1 precipitates. A very good combination of strength and ductility was observed for the alloy tested in FS processed condition. Detailed fractography was done to differentiate mode of fracture between as-received and FS processed conditions. Based on Schmid factor analysis, it was concluded that basal slip system controlled the yielding of the material in both the conditions. An empirical relationship was developed between work hardening rate and ductility. This can be applied to microstructural design of magnesium alloys used for applications where high uniform ductility is needed.
Local control of striatal dopamine release.

The mesolimbic and nigrostriatal dopamine (DA) systems play a key role in the physiology of reward seeking, motivation and motor control. Importantly, they are also involved in the pathophysiology of Parkinson’s and Huntington’s disease, schizophrenia and addiction. Control of DA release in the striatum is tightly linked to firing of DA neurons in the ventral tegmental area (VTA) and the substantia nigra (SN). However, local influences in the striatum affect release by exerting their action directly on axon terminals. For example, endogenous glutamatergic and cholinergic activity is sufficient to trigger striatal DA release independently of cell body firing. Recent developments involving genetic manipulation, pharmacological selectivity or selective stimulation have allowed for better characterization of these phenomena. Such termino-terminal forms of control of DA release transform considerably our understanding of the mesolimbic and nigrostriatal systems, and have strong implications as potential mechanisms to modify impaired control of DA release in the diseased brain. Here, we review these and related mechanisms and their implications in the physiology of ascending DA systems.
Genetic and antigenic analysis of the neuraminidase of influenza B viruses: association of neuraminidase in global spread and recycling of influenza B/Victoria/2/87-like viruses

Abstract After nearly a decade's absence in most parts of the world, influenza B/Victoria/2/87-lineage (Vic) viruses reappeared and rapidly spread globally in 2001. Genetic analysis of the hemagglutinin (HA) and the neuraminidase (NA) genes revealed that the majority of Vic-lineage viruses isolated since 2001 possessed an NA similar to that of a B/Yamagata/16/88(Yam)-lineage reference strain. This finding indicated that reassortment of the NA gene between two lineages of influenza B viruses was associated with the global spread of Vic-lineage viruses. We also found that a small proportion of recent Vic-lineage viruses inherited both their HA and NA genes from a Vic-lineage parental virus isolated in 1997. Although HAs of these viruses were similar to that of the parental virus, four amino acid (AA) substitutions were identified in their NAs. Therefore, mutations detected in the NAs of those recent influenza B viruses also may have played a role in the global spread of Vic-lineage, non-reassortant viruses.
Stabilized Finite Element Methods for Coupled Solid-Deformation/Fluid-Flow in Porous Geomaterials

We present a finite element formulation for saturated and partially saturated porous geomaterials undergoing elastoplastic deformations. The deforming body is treated as a multiphase continuum, and the governing mass and momentum balance equations are solved in a fully coupled manner. The constitutive behavior of the solid is based on a critical state plasticity model that explicitly accounts for the effect of capillary pressures on the geometry of the yield surface in the partially saturated regime. It is well known, however, that mixed formulations of the type examined here may lead to unstable approximations unless the spaces chosen for the pressure and displacement interpolations satisfy stringent stability restrictions. Failure to choose stable combinations typically leads to non-physical pressure oscillations and poor convergence behavior upon mesh refinement. Unfortunately, many seemingly natural combinations—including equal-order interpolations—do not satisfy the necessary requirements. In this work, we instead employ a stabilized formulation, based on a relatively minor modification of the variational equations, which allows us to circumvent these restrictions and employ equal-order mixed elements. We demonstrate the appealing features of this approach with several boundary value problems taken from geotechnical applications, including modeling strain localization and failure initiation in variably saturated slopes.Copyright © 2008 by ASME
Nature and nurture strike (out) again

This is a reply to the critique of the Scarr and Weinberg paper by Plomin. In addition, Munsinger's review of the adopted child literature is challenged as inaccurate and misleading. The need to discern mean effects in adoptions studies is highlighted by noting that mean scores show more malleability than rank order of individual scores, when the environments of adoptive families are well above the mean and when the variability with the group of families is restricted. Also discussed are alleged selective bias in the current pool of adoptees, the implicit assumptions in models that lead to heritability estimates, and the problems produced by the lack of a generally accepted model of environmental transmission.
Part II—What Parents Should Know and Do to Ensure Extracurricular Interscholastic Sport Opportunities for Their Children with Disabilities

Part II of the feature provides suggestions for parents to consider enacting with their local school district administration related to the inclusion of extracurricular sports on their child's individualized education program.
Minimum Weight Passive Insulation Requirements for Hypersonic Cruise Vehicles

Analytical solutions are derived for two representative cases of the transient heat conduction equation to determine the minimum weight requirements for passive insulation systems of hypersonic cruise vehicles. The cases discussed are the wet wall case with the interior wall temperature held to that of the boiling point of the fuel throughout the flight, and the dry wall case where the heat transferred through the insulation is absorbed by the interior structure whose temperature is allowed to rise.
“I know what you told me, but this is what I think:” Perceived risk of Alzheimer disease among individuals who accurately recall their genetics-based risk estimate

Purpose: This study evaluates the Alzheimer disease risk perceptions of individuals who accurately recall their genetics-based Alzheimer disease risk assessment. Methods: Two hundred forty-six unaffected first-degree relatives of patients with Alzheimer disease were enrolled in a multisite randomized controlled trial examining the effects of communicating APOE genotype and lifetime Alzheimer disease risk information. Results: Among the 158 participants who accurately recalled their Alzheimer disease risk assessment 6 weeks after risk disclosure, 75 (47.5%) believed their Alzheimer disease risk was more than 5% points different from the Alzheimer disease risk estimate they were given. Within this subgroup, 69.3% believed that their Alzheimer disease risk was higher than what they were told (discordant high), whereas 30.7% believed that their Alzheimer disease risk was lower (discordant low). Participants with a higher baseline risk perception were more likely to have a discordant-high risk perception (P < 0.05). Participants in the discordant-low group were more likely to be APOE e4 positive (P < 0.05) and to score higher on an Alzheimer disease controllability scale (P < 0.05). Conclusion: Our results indicate that even among individuals who accurately recall their Alzheimer disease risk assessment, many people do not take communicated risk estimates at face value. Further exploration of this clinically relevant response to risk information is warranted.
Sovereign Debt Defaults and Financing Needs

We construct a financial vulnerability indicator that is consistent with the theoretical literature on determinants of defaults. It is based on the amount of new foreign financing that is needed to avoid a default or an import adjustment, expressed as a proportion of the country`s sources of foreign currency. As the need for new foreign financing increases, so does a country`s financial vulnerability. The indicator has a higher correlation with default episodes than other indicators used in previous studies. In addition, the level at which it leads to a high probability of default is comparable across countries.
The steric requirements for sterol inhibition of tetrahymanol biosynthesis

Many naturally occurring sterols are accumulated and metabolized byTetrahymena pyriformis. In most cases, the sterols are desaturated to giveΔ5,7,22-derivatives. Compounds with an ethyl, but not with a methyl, substituent at C-24 are dealkylated. Exposure of the ciliates to the appropriate sterol sharply curtails the synthesis of the native pentacyclic triterpenoid alcohols, tetrahymanol and diplopterol. An analysis with modified sterols has revealed several additional features that are required for desaturation at C-7,8 and C-22,23 and for inhibition of tetrahymanol biosynthesis. The presence of atrans-17(20)-double bond, which eliminates free rotation at C-20 and fixes C-22 to the right of the nucleus, does not interfere with desaturation, while thecis- or left-handed isomer is not metabolized. Thecis-Δ17(20)-isomer is, however, an effective inhibitor of tetrahymanol biosynthesis, although less so that thetrans-counterpart. When a methyl or hydroxyl group at C-20 protrudes to the front of the molecule in the right-handed conformation, metabolism is reduced or abolished. Shortening (by one C-atom) or lengthening of the sterol side chain has little effect on the ability of the compounds to inhibit tetrahymanol biosynthesis or to support growth, as long as the overall length of the side chain does not exceed seven carbons from C-20. The presence of a 7α-, 7β-, 20α-, 20β-, or a 25-hydroxy group in the cholesterol molecule sharply inhibits desaturation and curtails the effectiveness of the compound as an inhibitor of tetrahymanol biosynthesis. The 7- or 22-keto derivatives seem to act in a fashion similar to the hydroxy derivatives, but these compounds show greater inhibition of growth. 20-Methylcholesterol, however, is a potent inhibitor of synthesis, which suggests that the polarity of the substituent of C-20 is more important than bulk. Many sterols can effectively replace tetrahymanol in the membranes of these ciliates. However, several of the compounds, which inhibit synthesis, appear to be physiologically inappropriate, and poor growth results. An example of the latter class is 20-methylcholesterol. Finally, a class of sterols, represented by 20α-hydroxycholesterol and 7-ketocholesterol, does not severly inhibit tetrahymanol synthesis but leads to growth inhibition and surface abnormalities. These sterols apparently lead to a disordered membrane, even in the presence of tetrahymanol.
The Effects of Gonadotropin-Releasing Hormone and Estradiol on Luteinizing Hormone Biosynthesis in Cultured Rat Anterior Pituitary Cells*

This study investigated the effects of physiological concentrations of GnRH and estradiol (E2) on LH biosynthesis and release using cultured anterior pituitary cells. Pituitaries from female rats were enzymatically dispersed and cultured for 48 h in steroid-free alpha-Modified Eagle's Medium, followed by a 24-h culture in medium with or without E2. The cells were then incubated for a 4-h (Exp 1 and 2) or 8-h (Exp 3) period in medium containing radiolabeled precursors with or without GnRH. Radioactive precursor incorporation into LH was determined by immunoprecipitation, while immunoreactive LH (iLH) content was quantified by RIA. In the first experiment, all concentrations of E2 (10(-11)-10(-8) M) enhanced iLH release in response to 1 nM GnRH, confirming previous reports. GnRH increased [3H]glucosamine (3H-Gln) incorporation into LH, but had no effect on [35S]methionine (35S-Met) incorporation. The higher concentrations of E2 enhanced GnRH-stimulated 3H-Gln LH production. In the second experiment, the effects of GnRH (10(-9) M) and E2 (5 X 10(-10) M) on the incorporation of [3H]galactose, [3H]mannose, [3H]fucose, or [35S]sulfate into LH were investigated. Although all precursors were incorporated into LH, no specific effect of GnRH and/or E2 on incorporation of any of the precursors into LH was noted. In Exp 3, pituitary cells were cultured with or without 0.5 nM E2 followed by an 8-h incubation with varying physiological concentrations of GnRH (10(-11)-10(-9) M) and radiolabeled precursors (3H-Gln and 35S-Met). GnRH stimulated iLH release in a dose-dependent manner, and this response was enhanced by E2. GnRH also increased the incorporation of both 3H-Gln and 35S-Met into LH, but the dose of GnRH required for this response was dependent upon the estrogen environment. In the absence of E2, only 10(-9) M GnRH increased 3H-Gln LH and 35S-Met LH production, whereas in cells exposed to E2, all concentrations of GnRH (10(-11)-10(-9) M) increased 3H-Gln LH and 35S-Met LH production. In all experiments, the specific activity of radiolabeled LH released under basal conditions was greatly reduced by stimulation with GnRH. These results suggest that GnRH regulates both LH glycosylation and LH polypeptide synthesis and that E2 lowers the physiological concentration of GnRH necessary to stimulate this biosynthetic response. Moreover, estrogen's enhancement of GnRH-stimulated LH release appears to be due to its action on mechanisms regulating the release of previously synthesized stored hormone as well as the release of newly synthesized LH.
Influence of changes in climate, sea level, and depositional systems on the fossil record of the Neoproterozoic-Early Cambrian metazoan radiation, Australia

On the Australian continent the fossil record of the initial appearance and radiation of higher metazoans is strongly influenced by the distribution of facies suitable for fossil preservation. The limited stratigraphic range of the [open quotes]Ediacaran[close quotes] fauna, the seemingly abrupt appearance and radiation of Cambrian-aspect traces, and the apparently late appearance of skeletogenous organisms are all functions of the spatial and temporal distributions of key habitats. The principal controls on the formation of these habitats appear to have been changes in climate and siliciclastic sediment supply coupled with cyclic changes in sea level. Aspects of the artifactual bias documented in Australia are recognized (but rarely documented) in Precambrian-Cambrian boundary sections worldwide. This bias may ultimately form a major stumbling block to detailed reconstruction of early metazoan evolution. 43 refs., 3 figs.
1D performance analysis and tracing of technical and Java applications on the Itanium2 processor

This paper presents a detailed workload characterization of important technical and Java/spl trade/ applications used in the industry, on the Itanium2 processor. We present a detailed performance study of four major classes of technical applications: 1- Crash finite element analysis (LS-Dyna3D). 2Structural analysis (Nastran). 3- Computational fluid dynamics (Star-CD). 4Other technical applications (GUPS). The performance of technical applications is compared to a commercial Java server benchmark (SPECjbb2000). The data indicate that the average IPC ratio of technical applications to that of the commercial Java application is from 1.23 to 2.36 (1.74 on average). We analyze the time varying behavior of the applications and collect instruction traces at both the kernel and user levels of representative sections of the code.
CONTACT AND FRACTURE ELEMENTS AS COMPONENTS OF THE RHEOLOGICAL MEMORY OF SOLID FOODS1

Most solid foods are rheologically nonlinear and their mechanical response may depend on their deformation history. Such behavior can be represented by modifying the conventional rheological models with discontinuous components. It is demonstrated that linear elastic and viscous elements combined with contact and fracture elements can form consistent models applicable under a wide range of deformation histories. This provides an explanation for the memory phenomena based on the physical aspects of the deformation mechanism.
Characterization of a mutator system in maize

Abstract • A mutator system is described in maize that results in an approximately 30-fold increase in the seedling mutation rate. This rate is found to be stable for at least two generations. • The transmission of the mutator characteristic does not follow a simple Mendelian pattern. In outcrosses, for which a one-gene model would predict that 50 percent of the progeny should not possess the mutator, nearly 100 percent of the offspring showed mutability. Several hypotheses are considered as explanations for the observed transmission pattern. Data bearing on a couple of these hypotheses are considered. To date, the evidence would seem to rule out only one of the alternatives.
Continuity of the conceptual system across species

In a recent neuroimaging study of macaque monkeys, Gil-da-Costa and colleagues reported that a distributed circuit of modality-specific properties represents macaques' conceptual knowledge of social situations. The circuit identified shows striking similarities to analogous circuits in humans that represent conceptual knowledge. This parallel suggests that a common architecture underlies the conceptual systems of different species, although with additional systems extending human conceptual abilities significantly.
Microwave Plasma Chemical Vapor Deposition of Nano-Structured Sn/C Composite Thin-Film Anodes for Li-ion Batteries

Microwave Plasma Chemical Vapor Deposition of Nano-Structured Sn/C Composite Thin-Film Anodes for Li-ion Batteries M. Marcinek, L. J. Hardwick, T. J. Richardson, X. Song and R. Kostecki ∗ Environmental Energy Technologies Division Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA Abstract In this paper we report results of a novel synthesis method of thin-film composite Sn/C anodes for lithium batteries. Thin layers of graphitic carbon decorated with uniformly distributed Sn nanoparticles were synthesized from a solid organic precursor Sn(IV) tert-butoxide by a one step microwave plasma chemical vapor deposition (MPCVD). The thin-film Sn/C electrodes were electrochemically tested in lithium half cells and produced a reversible capacity of 440 and 297 mAhg -1 at C/25 and 5C discharge rates, respectively. A long term cycling of the Sn/C nanocomposite anodes showed 40% capacity loss after 500 cycles at 1C rate. Keywords: Sn/C; Lithium Batteries; Anode; Plasma; Microwave Corresponding author. E-mail address: r_kostecki@lbl.gov, tel: 00 1 510 486 6002, fax: 00 1 510 486 7303
L-ascorbyl-2-monophosphate has equal antiscorbutic activity as L-ascorbic acid but L-ascorbyl-2-sulfate is inferior to L-ascorbic acid for channel catfish

Channel catfish (Ictalurus punctatus) fin- gerlings (13 g average initial weight) were fed semipu- rified diets supplemented with 0, 0.06, 0.12, 0.24 and 0.72 mmol/kg (0, II, 22,44 or 132 mg/kg) of ascorbic acid molar equivalent supplied by either L-ascorbic acid, L-ascorbyi-2-monophosphate (Mg salt) (AAP), or L-as- corbyI-2-suIfate (K satt) (AAS). After 14 wk, weight gains were equal for all fish fed diets containing L- ascorbic acid or AAP; however, growth rates were less for fish fed AAS at all dietary levels and for fish fed the ascorbic acid-free diet (control). There were no gross signs of vitamin C deficiency in any of the fish fed L- ascorbic add or AAP, whereas spinal deformities were found in the controls and in fish fed all but the highest concentration of AAS. The percentage of spinal defor mities decreased as dietary levels of AAS increased. Reduced bone collagen content and histopathology in liver and gill tissues also indicated ascorbic acid defi ciency in the controls and in fish fed all but the highest concentration of AAS. Limitedhistopathology was found in fish fed the lowest level of L-ascorbic acid but not in those fed the lowest level of AAP. Regression analysis of weight gain data showed that the vitamin activity of ascorbic acid from AAS was only 5.2% of that from L- ascorbic acid for growth. This study indicates that AAP has equimolar activity to L-ascorbic acid as a vitamin C source for channel catfish and that AAS has vitamin activity for this species but at a much lower level than the other compounds. J. Nutr. 121: 1622-1626, 1991.
The Susceptibility to Experimental Myasthenia Gravis of STAT6−/− and STAT4−/− BALB/c Mice Suggests a Pathogenic Role of Th1 Cells

Autoantibodies to the muscle acetylcholine receptor (AChR) cause the symptoms of human and experimental myasthenia gravis (EMG). AChR-specific CD4+ T cells permit development of these diseases, but the role(s) of the Th1 and Th2 subsets is unclear. The STAT4 and STAT6 proteins, which mediate intracellular cytokine signaling, are important for differentiation of Th1 and Th2 cells, respectively. Wild-type (WT) BALB/c mice, which are prone to develop Th2 rather than Th1 responses to Ag, are resistant to EMG. We have examined the role of Th1 and Th2 cells in EMG using STAT4 (STAT4-/-)- or STAT6 (STAT6-/-)-deficient BALB/c mice. After AChR immunization, STAT6-/- mice were susceptible to EMG: they developed more serum anti-AChR Ab, and had more complement-fixing anti-AChR IgG2a and 2b and less IgG1 than WT or STAT4-/- mice. The susceptibility to EMG of STAT6-/- mice is most likely related to the Th1 cell-induced synthesis of anti-AChR Ab, which trigger complement-mediated destruction of the neuromuscular junction. CD4+ T cells of the STAT6-/- mice had proliferative responses to the AChR comparable to those of WT and STAT4-/- mice, and recognized similar AChR epitopes. STAT6-/- mice had abundant AChR-specific Th1 cells, which were nearly absent in WT and STAT4-/- mice. Spleen and lymph nodes from STAT6-/- mice contained cells that secreted IL-4 when cultured with AChR: these are most likely STAT6-independent cells, stimulated in a non-Ag-specific manner by the cytokines secreted by AChR-specific Th1 cells.
Allometric Equations for Ashe Juniper (Juniperus ashei) of Small Diameter

Abstract Native species of juniper are encroaching on grasslands throughout the Great Plains. Prescribed fire is often used to treat or prevent the early stages of encroachment, but little information is available about the contribution of small junipers to overall fuel loads. I sampled 33 individuals of Ashe juniper (Juniperus ashei) from grasslands on Fort Hood Military Reservation, Texas. The relationship between size and above-ground biomass differed for small and larger trees. I focused most of my analyses on small trees (<15 cm in basal diameter), which are most likely to burn in a prescribed fire. Allometric equations based on basal diameter (BD) or basal diameter and height (BD2H) predicted total biomass better than equations using only tree height, canopy area, or canopy volume (r2 = 0.95–0.97 versus r2 = 0.71–0.77). Living and total biomass for smaller fuel-classes (<25 mm in diameter) were more accurately predicted than dead biomass and larger fuel-classes (r2 = 0.94–0.98 versus r2 = 0.75–0.87)...
Effects of Acute Stanozolol Treatment on Puberty in Female Rats

The effects of anabolic-androgenic steroid (AAS) abuse on the onset of puberty in female adolescents are largely unknown. This study assessed the acute effects of one AAS, stanozolol, on pubertal onset in the female rat. A single injection of stanozolol (5 mg/kg) on Postnatal Day (PN) 21 advanced vaginal opening but did not alter the onset of vaginal estrus. Higher doses of stanozolol treatment (10 and 25 mg/kg) also advanced vaginal opening but had no effect on vaginal estrus. The advancement of vaginal opening by stanozolol (5 mg/kg) was prevented by the concomitant administration of the pure antiestrogen ICI 182,780 (1 mg/kg) on PN20‐22. Administration of the androgen receptor antagonist flutamide (10 mg/kg twice daily) on PN20‐ 22 had no effect on the advancement of vaginal opening by stanozolol. Stanozolol treatment also advanced vaginal opening in ovariectomized rats. Perivaginal injections of a low dose of stanozolol (0.05 mg) on PN21 and PN23 also advanced vaginal opening. These results suggest that stanozolol is acting directly at estrogen receptors in the vaginal epithelium to advance vaginal opening and that prepubertal stanozolol treatment does not induce true precocious puberty. androgen receptor, estradiol receptor, hormone action, puberty, vagina
Heart Rate and Physical Activity of Children During Dental Treatment

Body movements and heart rate were measured during dental treatment in 58 children 3 to 12 years of age. The heart rate increased in 85% of the 34 children who moved during intraoral injection. The heart rate decreased in 71% of the children with no overt body movement during intraoral injection.