cssi/SciSciGPT-SciSciNet huggingface dataset:
Detection of a Faint Fast-moving Near-Earth Asteroid Using the Synthetic Tracking Technique

We report a detection of a faint near-Earth asteroid (NEA) using our synthetic tracking technique and the CHIMERA instrument on the Palomar 200 inch telescope. With an apparent magnitude of 23 (H = 29, assuming detection at 20 lunar distances), the asteroid was moving at 6o.32 day^(–1) and was detected at a signal-to-noise ratio (S/N) of 15 using 30 s of data taken at a 16.7 Hz frame rate. The detection was confirmed by a second observation 77 minutes later at the same S/N. Because of its high proper motion, the NEA moved 7 arcsec over the 30 s of observation. Synthetic tracking avoided image degradation due to trailing loss that affects conventional techniques relying on 30 s exposures; the trailing loss would have degraded the surface brightness of the NEA image on the CCD down to an approximate magnitude of 25 making the object undetectable. This detection was a result of our 12 hr blind search conducted on the Palomar 200 inch telescope over two nights, scanning twice over six (5o.3 × 0o.046) fields. Detecting only one asteroid is consistent with Harris's estimates for the distribution of the asteroid population, which was used to predict a detection of 1.2 NEAs in the H-magnitude range 28-31 for the two nights. The experimental design, data analysis methods, and algorithms are presented. We also demonstrate milliarcsecond-level astrometry using observations of two known bright asteroids on the same system with synthetic tracking. We conclude by discussing strategies for scheduling observations to detect and characterize small and fast-moving NEAs using the new technique.
Best Practice Recommendations for the Use of Hepatitis C Viremic Donor Organs for Hepatitis C Virus Naïve Recipients.

The combination of the transplant organ deficit, the increase in HCV nucleic acid positive donors (HCV NAT+), and the development of direct-acting antiviral agents (DAAs) has resulted in a rapid increase in HCV NAT+ organ transplants into HCV naive recipients. Early clinical experience with HCV NAT+ donor organs has shown promising outcomes; however, best practices are lacking to guide transplant programs during all phases of patient care. Transplant programs developing protocols for the utilization of HCV NAT+ organs will need a multidisciplinary team to address all aspects of pre-transplant and post-transplant patient care. Reports of fibrosing cholestatic hepatitis in HCV NAT+ organ transplant recipients receiving delayed DAA initiation highlight the need for the transplant community to develop safe and effective protocols. A failure to do so will inevitably lead to the erosion of public trust from cases of missed or inadequately treated donor-derived HCV infections. Herein, we provide best practice guidelines for the utilization of HCV NAT+ organs into HCV-negative recipients based on literature review and expert opinion from the faculty of the ASTS Standards and Quality Committee.
Pseudomonas synergizes with fluconazole against Candida during treatment of polymicrobial infection

Polymicrobial infections are challenging to treat because we don9t fully understand how pathogens interact during infection and how these interactions affect drug efficacy. Candida albicans and Pseudomonas aeruginosa are opportunistic pathogens that can be found in similar sites of infection such as in burn wounds and most importantly in the lungs of CF and mechanically ventilated patients. C. albicans is particularly difficult to treat because of the paucity of antifungal agents, some of which lack fungicidal activity. In this study, we investigated the efficacy of anti-fungal treatment during C. albicans-P. aeruginosa co-culture in vitro and co-infection in the mucosal zebrafish infection model analogous to the lung. We find that P. aeruginosa enhances the activity of fluconazole (FLC), an anti-fungal drug that is fungistatic in vitro, to promote both clearance of C. albicans during co-infection in vivo and fungal killing in vitro. This synergy between FLC treatment and bacterial antagonism is partly due to iron piracy, as it is reduced upon iron supplementation and knockout of bacterial siderophores. Our work demonstrates that FLC has enhanced activity in clinically relevant contexts and highlights the need to understand antimicrobial effectiveness in the complex environment of the host with its associated microbial communities.
Global Responses of Bacteria to Oxygen Deprivation

This chapter highlights some of the advances on both the molecular mechanisms of oxygen (O2) sensing and the biological responses to O2 limitation. In the first part of the chapter, the major regulators that control expression of anaerobic respiratory pathways are described, with focus on the well studied examples from Escherichia coli K-12. Many facultative bacteria have anaerobic lifestyles that depend on pathways not found in enteric bacteria. A section reviews the master regulators of these anaerobic lifestyles, describing how their activity responds to O2 deprivation, highlighting commonalities and differences to the responses described for enterobacteria, and placing them into a metabolic context of the systems they control. A recurring theme in the review is that multiple transcription factors collaborate in a given organism to control gene expression in response to changes in O2. In E. coli, decreased expression of the genes encoding aerobic respiratory functions under anaerobic growth conditions is largely mediated by the aerobic respiration control (Arc) A and ArcB two-component system. Regulation of anaerobic respiration in the γ-proteobacterium Shewanella oneidensis has attracted great interest because of the broad diversity of electron acceptors (>14) that these bacteria can respire, including metal oxides. The use of cofactors such as flavins, heme, and [Fe-S] clusters generally sense O2 directly, using chemistry reflecting their well-described roles in biological reactions.
New Problems with Rate-Adaptive Pacing: Limitations, Adverse Effects, and Interference

The widespread use of rate-adaptive pulse generators has created new problems specifically related to the sensor or rate-adaptive function that regulates the pacing rate. Many sensor-driven devices are still investigational and some are not generally available in the United States. This chapter focuses on the limitations, adverse effects, and interference of rate-adaptive pacemakers available in the United States as of the end of 1991. Rate-adaptive pacemakers approved for general use in the United States by the Food and Drug Administration utilize sensor input from activity, minute ventilation volume, and temperature to modulate the pacing rate [1].
Pancreatic Cancer Resistance to TRAIL Therapy: Regulators of the Death Inducing Signaling Complex

Pancreatic cancer is the fourth leading cause of cancer deaths in the United States. It is generally a fatal cancer with poor prognosis. Once pancreatic cancer becomes metastatic, it is uniformly fatal with an overall average survival of typically 6 months. The only potentially curative therapy for pancreatic cancer is surgical resection. Unfortunately, the majority of pancreatic cancer patients have advanced and inoperable disease at the time of diagnosis. Studies from our group and others have supported that modulating tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis provides potential novel avenues for cancer therapy. However, resistance of pancreatic cancer to TRAIL therapy remains a large clinical hurdle. Thus, better understanding of the molecular events regulating pancreatic cancer cell apoptosis would facilitate the development of novel strategies to enhance the efficacy of TRAIL therapy.
Differential Regulation of Functional Gene Clusters in Overt Coronary Artery Disease in a Transgenic Atherosclerosis-hypertensive Rat Rodel

Human acute coronary syndrome refers to the spectrum of clinical manifestations of overt coronary artery (CAD) disease characterized by atherosclerotic plaque destabilization and resultant myocardial injury. Typically studied as distinct pathologies, emerging pathogenic paradigms implicate multiple processes beyond thrombosis and ischemic cell injury respectively, with significant pathway overlap involving inflammation, apoptosis, matrix degradation, and oxidative stress. However, all these pathways have also been implicated in still-quiescent coronary plaque progression, thus making it harder to pinpoint the turnkey events leading to overt-CAD. Analysis of transcription profiles could identify a working framework of pathogenesis distinguishing overt-CAD. We investigated the transcription profile associated with overt-coronary artery disease (CAD), in contrast to quiescent-CAD and attenuated, quiescent-CAD using the Tg53 transgenic atherosclerosis-hypertensive rat model, which exhibits end-stage coronary heart disease simulating human acute coronary syndromes. Using a rat-specific known-gene oligonucleotide array, twice corroborated transcription profiles from four individual Tg53 rats exhibiting overt-CAD were analyzed and contrasted to transcription profiles of age-matched Tg53 rats with quiescent-CAD (pooled n = 4) and attenuated, quiescent-CAD (pooled n = 4). Tg53 male rats with overt-CAD exhibited distinct transcription profiles compared with both quiescent-CAD control groups. Functional gene cluster analysis detects upregulation of genes involved in inflammation (interleukin-1, interleukin-18, FcγII receptor, thyrotropin releasing hormone), matrix balance (membrane type metalloproteinase, TIMP-1, lysyl oxidase), oxidized LDL entry (endothelial oxLDL receptor), which contrast deinduced gene clusters involved in angiogenesis, proliferation, metabolism, ion transport and adrenergic receptors. The data demonstrate that transcriptionally mediated events distinguish the onset of overt-CAD and identify a first list of putative “turnkey” genes. This altered molecular framework implies an altered “hardwiring” which a priori would require multifaceted, targeted intervention-currently not implemented to date. Although more studies are necessary, early concordance with current pathogenic paradigms of human coronary plaque destabilization and post-ischemic myocardial response provides translational significance to observations and hypotheses.
Regulation of quantal shape by Rab3A: evidence for a fusion pore-dependent mechanism

The function of Rab3A, a small GTPase located on synaptic vesicles, is not well understood. Studies in the Rab3A−/− mouse support a role in activity-dependent plasticity, but have not reported any effects on spontaneously occurring miniature synaptic currents, except that there is a decrease in resting frequency at the neuromuscular junction. Therefore we were surprised to find an increase in the occurrence of mEPCs with abnormally long half-widths at the neuromuscular junctions of Rab3A−/− mice. The abnormal miniature endplate currents (mEPCs), which have significantly greater charge than the average mEPCs for the same fibres, could arise from larger vesicles. However, the type of mEPC most increased in Rab3A−/− mice has a slow rise, which suggests it is not the result of full collapse fusion. To test if the slow mEPCs increased after loss of Rab3A could be due to malfunctioning fusion pores, we used carbon fibre amperometry to record pre-spike feet, which have been shown to correspond to the initial opening of a narrow fusion pore, in adrenal chromaffin cells of wild-type and Rab3A−/− mice. We found that small amplitude pre-spike feet with abnormally long durations were increased in Rab3A−/− cells. The correspondence between mEPC and amperometric data supports our interpretation that slow rising, long half-width mEPCs are caused by reduced diameter fusion pores that remain open longer. These data could be explained by a direct action of Rab3A on the fusion pore, or by Rab3A-dependent control of vesicles with unusual fusion pore characteristics.
Option Pricing Model for Autocorrelated Stock Returns

This paper develops an analytic option pricing model for the case of serially correlated asset returns. This model provides a valuable insight into dependence of option price on the return autocorrelation. A surprising relationship is found between asset price volatility, asset return volatility and asset return autocorrelation coefficient. The analytical solution obtained here reduces to the well known Black Scholes option pricing formula for the special case of no autocorrelation in asset returns. However, in the case of serially correlated asset returns, our model provides superior results by controlling for the difference between asset price volatility and asset return volatilities. Empirical tests obtain statistically and economically significant results demonstrating the superiority of our model when compared to the traditional Black Scholes formula. Additionally, a Monte Carlo method is developed to price option for assets with autocorrelated returns. Numerical comparison between these two methods demonstrate strikingly similarity, being equal to within the computational error. This serves to affirm the validity of our method.
Ultrafast "Fermat" photons migration in turbid media: the least mean square curvature of the most favorable paths

Summary form only given. To describe the photon migration in highly forward scattering turbid media on a femto-picosecond fine time scale, the idea of photon diffusion on the velocity sphere is introduced, which leads to a non-Euclidean diffusion equation (NED).
Phonological words and syntactic constituents in XiTsonga

The distinction between phonological and syntactic words, most evident in cases of discord between the domain of the Dokean phonological word and constituent structure, is considered. The integrity of the unit noun class prefix + stem, a central concept in Bantu morphosyntax, is questioned. It is argued that the class prefix is sister not to a following noun but to the whole of the NP (noun prefix). Support for this claim derives from limitations on High Tone Spread, a tonological process sensitive to syntactic brackening within an object NP. The analysis, offered in the framework of autosegmental phonology, also provides an explanation for the so-called ‘neutral tone’ prefixes of Tsonga, previously described by reference to dissimilation.
What Hath Nature Wrought

Down to Earth Nature9s Role in American History. Ted Steinberg. Oxford University Press, New York, 2002. 361 pp. $30. ISBN 0-19-514009-5. Steinberg presents an account of the influence of the environment-and human interactions with it-on U.S. history, our current circumstances, and our future prospects.
Bell-to-Bell Teaching: Making Every Minute Count!

Physical educators may not have control over the resources or the amount of time provided, but they can control the effort put forth every day in physical education classes by making every minute count. This article provides a number of strategies to minimize class-management and instruction time issues, while increasing the amount of time students are actively engaged in appropriate physical activity.
MONTE CARLO SIMULATION OF SHOCK-INDUCED LATTICE DAMAGE

We have developed a new technique, based on the Monte Carlo method, for simulation of the atomic-scale effects of shock loading upon model systems. Metastable atomic configurations resulting from strain rates which are fast or slow relative to congurational equilibration rates can be calculated. Using this technique to simulate uniaxial shock and quasi-static loading of 2-D argon, we find that the degree of defectiveness strongly depends upon the strain rate. This observation may help explain the observed difference in chemical reactivity under quasi-static and shock loading.
Statistical-band-model analysis and integrated intensity for the 21.8 micrometer bands of HNO3 vapor

A large number of low-resolution quantitative spectra were obtained for a band-model analysis of 21.8-micrometer bands. The experimental investigations were conducted with pure nitric-acid vapor at 40 C, taking into account pressures in the range from a few torr to a pressure which is close to the saturation pressure. It is pointed out that the obtained data, in addition to those from the 11.3-micrometer band, can be used for an independent determination of the nitric acid vertical distribution in the stratosphere.
The behavioral pharmacology of ingestive behavior

Publisher Summary This chapter describes the behavioral pharmacology of ingestive behavior. The use of drugs in the study of ingestion usually has one of two principal objectives: either to use a drug as a specific probe of a defined neurotransmitter/modulator/messenger system or as a screening procedure for potential clinical use. These two approaches are not mutually exclusive and many studies can be designed with a view to helping both of these objectives. Because most such studies are performed in nonhumans, the animal model must be chosen carefully to match the objectives. In short term tests, as might be chosen for study after acute administration of a short-acting drug, gravimetric, volumetric for a liquid diet, measurement of consumption is common. The simplest situation is to present a preweighed amount of food and to weigh the remainder after designated interval(s). This chapter describes some of the procedures and analyses that have proven useful in the examination of effects of drugs on food and fluid intake. It describes methods for studying food intake in animals and humans. The chapter also describes methods applicable to study of fluid intake including alcohol.
S-wave Quarkonium Spectral Functions Above Tc

The temperature-dependence of charmonium and bottomonium spectral functions is discussed in a nonrelativistic Green's function approach using different potentials. The results are compared to lattice data.
Cyclic AMP-Dependent Protein Kinase Isozymes of Pig Skin and Human Skin from Normal and Psoriatic Subjects

Cyclic AMP-dependent protein kinase isozymes of pig and human skin (epidermis) were separated by DEAE- cellulose column chromatography after micromodification for small biopsy samples. Clear-cut separations of type I and type II isozymes, winch were of about equal amounts, could be obtained only when the ischemia effect was avoided by in vivo freezing of skin and homogenization for less than 10 s. Intradermal injections of epinephrine caused dose-dependent activation of type I isozyme, but not of type 11. Injections of other skin adenylate cyclase stimulators such as histamine, adenosine, and prostaglandin E 2 elevated the local cyclic AMP levels to not more than 5 pmol/mg protein and also stimulated only the type I isozyme. Incubation of keratome-sliced pig skin under various conditions caused both activation by dissociation and inactivation by dissociation of the subunits, which appeared to be dependent on the cyclic AMP content. Epinephrine added to the incubation medium led to complete activation of both type I and type II isozymes (the intraepidermal cyclic AMP contents ranged from 20–50 pmol/mg protein). The isozymes of normal skin and involved skin of psoriatics showed identical peaks of type I and type II Isozymes of equal amounts. The data indicate that protein kinase in the involved skin is not in an activated (by cyclic AMP) state.
Between the devil and the deep blue sea: mercantilism and free trade

Taking the work of radical dependency theorist Clive Thomas as its starting point, this article examines the structural effects on Caribbean economies of capitalist globalisation, neoliberal `adjustment' programmes and the imposition of `free market' rules of trade. It looks at the interplay between the powerful corporations and nation states and asks whether the region's `underdevelopment' is a product of its comparatively small size or of its colonial history. Arguing that the latter was the principal factor, it analyses both the sugar and the banana industries in terms of their forced accommodation to the dictates of imperialism, to provide lessons for the present.
HIV Risk Reduction among Young Minority Adults in Broward County

We examined changes in perceptions of HIV risk, abstinence, condom use, and intentions to use condoms for disease protection among African American, Hispanic, Haitian, and Afro-Caribbean unmarried and married men and women living in Broward County, Florida. Data were collected through computer-assisted telephone interview sur- veys conducted during 2001, 2002, and 2003 with cross-sectional probability samples of 18-39 year old residents of 12 high AIDS incidence ZIP code areas. Perceptions of HIV risk increased over time for men, but not for women. Unmarried Haitian women 18-22 years old were most likely to report abstinence. Condom use during the last 12 months increased among sexually active respondents. Among residents reporting exposure to project interventions, condom use increased from 53.6% in 2001 to 64.7% in 2002 and 71.6% in 2003. HIV-prevention programs should (1) consider locally collected data; (2) take into account cultural, living situation, and other significant differences; and (3) be evaluated to assess differentiated impact.
Gate dielectric and contact effects in hydrogenated amorphous silicon‐silicon nitride thin‐film transistors

The characteristics of glow‐discharge hydrogenated amorphous silicon‐silicon nitride (a‐Si:H/a‐SiNx:H) thin‐film transistors (TFTs) are reported for various deposition conditions. TFTs incorporating a N‐rich nitride gate dielectric, a‐SiN1.6:H, are superior to a‐Si:H TFTs with a Si‐rich gate nitride, a‐SiN1.2:H. In particular, the N‐rich gate nitride TFTs show considerably less interface or near‐interface charging during operation, improved stability, and a higher field‐effect mobility. The average field‐effect mobility μFE is found to be 0.27 and 0.41 cm2/V s for the Si‐ and N‐rich gate nitride TFTs, respectively. A further improvement in mobility, μFE =0.61 cm2/V s, is achieved by increasing the N‐rich gate nitride deposition temperature from 250 to 450 °C. These results suggest that N‐rich a‐SiNx:H, deposited at elevated temperatures, yields a more abrupt or ‘‘cleaner’’ a‐SiNx:H/a‐Si:H interface. We also show, for the first time, that using n+ μc‐Si:H source‐drain contacts in place of n+ a‐Si:H improve...
Carbonate on Ag(110): a complex system clarified by STM

Abstract In the present work we have used scanning tunneling microscopy (STM) in conjunction with temperature programmed reaction spectroscopy (TPRS) to study the formation of surface carbonate on Ag(1 1 0) by the reaction of CO2 with atomic oxygen. Recently, we have found and reported that the STM images attributed previously to carbonate are actually due to chemisorbed CO2. STM images reported here reveal that the surface carbonate species on Ag(1 1 0) has a very different appearance from chemisorbed CO2. Chemisorbed CO2 appears as round protrusions, whereas carbonate forms thick rods along the [1 1 0] direction consisting of double or single chains. An adsorption structure model consistent with the STM observation and the (1×2) reconstruction is suggested. Images recorded at various oxygen coverages show that the carbonate rods form between the –Ag–O– rows and accumulate near step edges. In situ STM imaging during carbonate formation demonstrates that the reaction may initiate at the end or from the side of the –Ag–O– rows. The reaction progresses along the rows.
Frequency-dependent electrostatic actuation in microfluidic MEMS

Electrostatic actuators exhibit fast response times and are easily integrated into microsystems because they can be fabricated with standard IC micromachining processes and materials. Although electrostatic actuators have been used extensively in "dry" MEMS, they have received less attention in microfluidic systems probably because of challenges such as electrolysis, anodization, and electrode polarization. Here we demonstrate that ac drive signals can be used to prevent electrode polarization, and thus enable electrostatic actuation in many liquids, at potentials low enough to avoid electrochemistry. We measure the frequency response of an interdigitated silicon comb-drive actuator in liquids spanning a decade of dielectric permittivities and four decades of conductivity, and present a simple theory that predicts the characteristic actuation frequency. The analysis demonstrates the importance of the native oxide on silicon actuator response, and suggests that the actuation frequency can be shifted by controlling the thickness of the oxide. For native silicon devices, actuation is predicted at frequencies less than 10 MHz, in electrolytes of ionic strength up to 100 mmol/L, and thus electrostatic actuation may be feasible in many bioMEMS and other microfluidic applications.
Mental Causation and the Agent-Exclusion Problem

The hypothesis of the mental state-causation of behavior (the MSC hypothesis) asserts that the behaviors we classify as actions are caused by certain mental states. A principal reason often given for trying to secure the truth of the MSC hypothesis is that doing so is allegedly required to vindicate our belief in our own agency. I argue that the project of vindicating agency needs to be seriously reconceived, as does the relation between this project and the MSC hypothesis. Vindication requires addressing what I call the agent-exclusion problem: the prima facie incompatibility between the intentional content of agentive experience and certain metaphysical hypotheses often espoused in philosophy–metaphysical hypotheses like physical causal closure, determinism, and the MSC hypothesis itself. I describe several radically different approaches to the vindication project, one of which would repudiate the MSC hypothesis and embrace metaphysical libertarianism about freedom and determinism. I sketch the position I myself favor–a specific version of the generic approach asserting that the intentional content of agentive experience is compatible with the MSC hypothesis (and with physical causal closure, and with determinism). I describe how my favored approach can plausibly explain the temptation to embrace incompatibilism concerning the agent-exclusion problem.
The evaluation of culpability for rape: A model of legal decision making

Abstract An analogy was borrowed from the law to develop a legal model of the attribution of responsibility for rape. According to the model, judgments of physical and psychological causality of an alleged rapist are combined into overall evaluations of attacker responsibility. An experimental test of the model was conducted with college students. Results showed that witness identification information influenced judgments of physical causality (i.e., extent to which the situation was perceived as rape), and information about the relationship between the alleged attacker and victim influenced judgments of psychological causality (i.e., intention to rape). Judgments of physical and psychological causality interacted significantly with overall attributions of attacker responsibility.
Evaluation of AMG 076, a potent and selective MCHR1 antagonist, in rodent and primate obesity models

Melanin-concentrating hormone (MCH) regulates food intake through activation of the receptor, MCHR1. We have identified AMG 076 as an orally bioavailable potent and selective small molecule antagonist of MCHR1. In mouse models of obesity, AMG 076 caused a reduction in body weight gain in wild-type (MCHR1+/+) but not in knockout (MCHR1−/−) mice. The body weight reduction was associated with decreases in food intake and increases in energy expenditure. Importantly, we show that these MCHR1-dependent effects of AMG 076 were also reflected in improved metabolic phenotypes, increased glucose tolerance and insulin sensitivity. Preliminary data on effects of AMG 076 in obese cynomolgus monkeys are also presented.
Selecting the Number of Principal Components in Functional Data

Functional principal component analysis (FPCA) has become the most widely used dimension reduction tool for functional data analysis. We consider functional data measured at random, subject-specific time points, contaminated with measurement error, allowing for both sparse and dense functional data, and propose novel information criteria to select the number of principal component in such data. We propose a Bayesian information criterion based on marginal modeling that can consistently select the number of principal components for both sparse and dense functional data. For dense functional data, we also develop an Akaike information criterion based on the expected Kullback–Leibler information under a Gaussian assumption. In connecting with the time series literature, we also consider a class of information criteria proposed for factor analysis of multivariate time series and show that they are still consistent for dense functional data, if a prescribed undersmoothing scheme is undertaken in the FPCA algor...
The demonstration of angiogenic activity from ocular tissues. Preliminary report.

Abstract Human, bovine, and rabbit retinal extracts are shown to be capable of stimulating (1) proliferation and thymidine uptake of bovine vascular endothelial cells in culture and (2) neovascularization of the chick chorioallantoic membrane (CAM). Extracts of skeletal muscle, heart, and liver lack similar stimulatory activity. Vitreous aspirates from patients with proliferative diabetic retinopathy, in a preliminary study, were able to stimulate vascular endothelial cell thymidine uptake. Most vitreous samples from patients without intraocular neovascularization lacked similar stimulatory activity. Indirect evidence suggests the liberation of an angiogenic factor from the retina in several ocular disorders. The data contained in this report represent the first direct evidence of angiogenic activity from mammalian retina.
Specificity of Prion Assembly in Vivo [PSI+] AND [PIN+] FORM SEPARATE STRUCTURES IN YEAST

The yeast prions [PSI+] and [PIN+] are self-propagating amyloid aggregates of the Gln/Asn-rich proteins Sup35p and Rnq1p, respectively. Like the mammalian PrP prion "strains," [PSI+] and [PIN+] exist in different conformations called variants. Here, [PSI+] and [PIN+] variants were used to model in vivo interactions between co-existing heterologous amyloid aggregates. Two levels of structural organization, like those previously described for [PSI+], were demonstrated for [PIN+]. In cells with both [PSI+] and [PIN+] the two prions formed separate structures at both levels. Also, the destabilization of [PSI+] by certain [PIN+] variants was shown not to involve alterations in the [PSI+] prion size. Finally, when two variants of the same prion that have aggregates with distinct biochemical characteristics were combined in a single cell, only one aggregate type was propagated. These studies demonstrate the intracellular organization of yeast prions and provide insight into the principles of in vivo amyloid assembly.
Transfer of 3H-gossypol to neonatal rats via milk of nursing dams.

Abstract Gossypol is a naturally occuring toxin with potent antifertility action in both males and females. Transfer of gossypol via milk from lactating mother to neonates has not been documented. One theory for the lack of such a finding is that gossypol, once tightly bound to milk proteins, is not extractable by conventional extraction methods for HPLC analysis. This study was designed to examine the possibility and dynamics of transmammary transfer of radioactively-labelled gossypol to neonates through nursing. Nursing rats were dosed with fifty μCi of 3H-gossypol in 0.5 ml of dimethyl sulfoxide via oral intubation on Day 10 post-partum. Six hours after treatment, significant amounts of 3H-gossypol were detected in the coagulated milk collected from the stomachs of the neonates as well as in the blood, liver, lung, spleen and a number of other tissues of these pups. While most neonatal tissues showed a steady decline in 3H-gossypol retention over time regardless of neonatal gender, adrenal glands and gonads preferentially accumulated 3H-gossypol in a time- and sex-dependent manner during the 24-hour sampling period. The results demonstrate that 3H-gossypol is transferred via milk from the nursing dams to their neonates. Thus, the gossypol content of milk presents a conceivable threat to neonatal health, especially to the normal function of steroidogenic organs.
Simulation of diffusion-limited aggregation of pectin

Abstract End-to-end diffusion-limited aggregation of an ideal, monodisperse pectin species with variable probability of interrmolecular crosslinking has been simulated on a lattice. The aggregate was fixed on the lattice as a structure of segmented rods. The growth of averages of size, length, width, and radius of gyration followed a power law dependence on time as measured by number of random lattice movements of diffusing monomer. The structures exhibited multifractal properties that arise from both the diffusion process and the random generation of crosslinking sites. The growth of the average length of the structures was independent of probability of crosslinking under the condition of constant presence of diffusing monomer. The growth of the average size of the structures was directly related to the growth of the average number of crosslinks. Average length, width, and radius of gyration were related to growth of average size by power laws. Macintosh and IBM PC source code and executables are included on disk in this issue.
Inheritance of resistance in soybean PI 567516C to LY1 nematode population infecting cv. Hartwig.

Worldwide, cyst nematode (SCN) Heterodera glycines is the most destructive pathogen on cultivated soybean (Glycine max (L.) Merr.). In the USA yield losses in 2001 were estimated to be nearly 60 million dollars. Crop losses are primarily reduced by the use of resistant cultivars. Nematode populations are variable and have adapted to reproduce on resistant cultivars overtime because resistance primarily traces to two soybean accessions. Recently cv. Hartwig was released which has comprehensive resistance to most SCN populations. A virulent nematode population LY1 was recently selected for its reproduction on Hartwig. LY1 population originated from a mass mating of Race 2 (HG Type 1.2.5-) females with Race 5 (HG Type 1.2-) males. LY1 nematode population infects currently known sources of resistance except PI 567516C. The female indices obtained on PI 567516C and Hartwig were 7% (resistant) and 155% (susceptible), respectively. However, the genetic basis of LY1 resistance in soybean PI 567516C is not known. Resistant PI line 567516C was crossed to susceptible cultivar Hartwig to generate 105 F2:5 families. These families together with parents, seven indicator lines and a susceptible control cv. Lee-74 were evaluated for response to LY1 nematode population in the greenhouse. Chi-square analysis showed resistance in PI567516C to LY1 was conditioned by one dominant and two recessive genes (Rhg, rhg, rhg). Chi-square value was 0.15 and P = 0.70. This information will be useful to soybean researchers for developing resistant cultivars to nematode population that infects Hartwig.
Isotopic analysis of cometary organic matter

Carbon isotope ratios have been measured for CN in the coma of Comet Halley and for several CHON particles emitted by Halley. Of these, only the CHON-particle data may be reasonably related to organic matter in the cometary nucleus, but the true range of (C-13)/(C-12) values in those particles is quite uncertain. The D/H ratio in H2O in the Halley coma resembles that in Titan/Uranus.
Broad-band continuous-wave parametric wavelength conversion in silicon nanowaveguides

We demonstrate highly broad-band frequency conversion via four-wave mixing in silicon nanowaveguides. Through appropriate engineering of the waveguide dimensions, conversion bandwidths greater than 150 nm are achieved and peak conversion efficiencies of -9.6 dB are demonstrated. Furthermore, utilizing fourth-order dispersion, wave-length conversion across four telecommunication bands from 1477 nm (S-band) to 1672 nm (U-band) is demonstrated with an efficiency of -12 dB.
The referee role and norms of equity: A contribution toward a theory of sibling conflict.

A theory is offered which relates amount of conflict in the sibling relationship to norms of distributive justice, or equity, which exist within the family. The scope of the theory is limited to the parental referee role, and the consistency and congruity with which this role is enacted is hypothesized to directly influence the degree of sibling conflict, as well as the children's inclination to challenge parental norms and behavior. Less challenge and less conflict between sibs are both associated with referee behavior which is consistent and based on principles or rules which are verbally communicated to the children.
Focal adhesion kinase: an integrin-linked protein tyrosine kinase

Recent evidence has shown that binding of integrins to components of the extracellular matrix serves to initiate cellular signals, resulting in changes in cytoskeletal architecture and activation of intracellular signalling pathways. Here we review the evidence that protein tyrosine kinases, including focal-adhesion-associated kinases, play a central role in the generation of some of these molecular signals.
Reactions of 2,5-diphenyl-1,4 dithin sulfones with sodium azide

Abstract A number of unanticipated transformations were observed when various 2,5-diphenyl-1,4-dithiin sulfones were treated with sodium azide. These include a fragmentation to give 1,2-dicyano-1,2-diphenylethen, the formation of 2,5-dipehnyl-1,4-thiazine-1,1-dioxide, and the rearrangement of 3-bromo-2,5-diphenyl-1,4-dithiin-1,1-dioxide to its 2-bromo- isomer. Possible mechanism for these unusual reactions are discussed.
Characterizing the beam steering and distortion of focused Gaussian and Bessel beams in tissues

We evaluate the motion and distortion of low-NA focused Gaussian and Bessel beams in tissues with microscopic heterogeneities. Low-NA Bessel beams exhibit reduced beam steering and distortion compared to Gaussian beams, which could be advantageous for dual-axis confocal microscopy in tissues.
Improvement in Visual Sensitivity by Changes in Local Context: Parallel Studies in Human Observers and in V1 of Alert Monkeys

To explore the role of primary visual cortex in contour integration, we measured the contextual sensitivity of human contrast thresholds and of superficial layer complex cells in monkey V1. An observer's contrast detection was 40% improved by a second suprathreshold bar; the effect was decreased as the two bars were separated along their axis of orientation, were displaced from colinearity, and had their relative orientation changed. Recordings from V1 showed that 42% of complex cells demonstrated facilitation for a second bar outside their classical receptive fields with a similar dependency on relative location and orientation. Both effects were eliminated by an orthogonal line between the two iso-oriented lines. Multiple randomly placed and oriented lines in the receptive field surround often caused a reduction in a cell's response to an optimally oriented stimulus, but this inhibition could be eliminated by changing the orientation of a few of these elements to colinearity with the centrally located target.
Effects of Low Frequency Electromagnetic Field on the Solidification Structure of Al-4.5%Cu Alloy during Level Casting Process

On the basis of conventional level casting, low frequency electromagnetic field is applied during conventional level casting process. Effects of low frequency electromagnetic field on melt flow, macrostructure and microstructure have been studied. The experiment is performed on the Al-4.5% Cu alloy, and the experimental results show that with the application of the low frequency electromagnetic field, the macrostructure and microstructure are changed greatly. The reasons for the low frequency electromagnetic field changing the macrostructure and microstructure of the ingot were summarized.
The Electroencephalographic Response during a Driving Process: Normal Driving, Turning and Collision

The objective of this study is to estimate the driver's cognitive state under different situation and driving scenarios by analyzing EEG signal. The experiment was conducted on a high fidelity driving simulator. Three different scenarios were designed to investigate the driver's state during normally driving (braking and accelerating) and turning (left or right). In the daily-urban scenario, a deer collision occurred. During each driving trial, the EEG signal was recorded by a 32-lead system. The EEG dynamics were analyzed using power spectrum density (PSD), event-related potential (ERP), independent component analysis (ICA) and time-frequency analysis (TFA). In normally driving, the EEG responses are similar during the three different scenarios. The power concentrates on the frontal and back lobes. During turning, the EEG response is somehow different from that in normally driving (only braking and accelerating). In the deer-collision event, a rapid response is apparent in the ERP mapping.
Calibrated Models of Deicing Agent Solids, Pavement Texture, and Specific Conductivity of Highway Runoff

Field data and existing theory suggest that pavement texture governs the seasonal persistence of deicing agent solids and the storm scale variability of the specific conductivity of highway runoff. We measured precipitation, runoff, and specific conductivity for 50 storms over four deicing seasons at a highway drainage system in southeastern Massachusetts. An average pavement texture of 2.44 mm was measured and 5.17× 105 kg of calcium magnesium acetate, salt, and premix applications was reported as well. Catchments and a depression storage layer model the highway drainage system, which routes hyetographs and slowly dissolving deicing agent solids to storm scale hydrographs and specific conductivity pollutographs. We equate the average pavement texture to the depression storage layer depth, which receives applied deicing agent solids, controls their dissolution during a storm, and governs their seasonal scale persistence. The observed average pavement texture, precipitation, and deicing agent applications ...
Oxygen consumption in adult and aged C57BL/6J mice during acute treadmill exercise of different intensity

Submaximal and maximal oxygen consumption was determined in untrained adult and aged male C57BL/6J mice during treadmill running. Each of 12-month-old (ADULT) and 24-month-old (AGED) male mice was tested on a motor-driven treadmill once at different speeds. VO2 was measured before, during, and after exercise by means of indirect calorimetry in metabolic treadmill chambers. The resting VO2 averaged 3064.67 +/- 87.71 mL/kg/h for ADULT mice and 2472.95 +/- 69.41 mL/kg/h for AGED mice. During exercise, VO2 increased linearly with work intensity (running speed): ADULT mice--from 5908.06 +/- 422.35 mL/kg/h at 3 m/min to 10861.99 +/- 174.03 mL/kg/h at 25 m/min; AGED mice--from 5217.25 +/- 263.26 mL/kg/h at 3 m/min to 7817.32 +/- 290.28 mL/kg/h at 20 m/min. Further increase of the running speed resulted in a decline of VO2 in ADULT and refusal to run in AGED mice. The results of this study demonstrated that in untrained C57BL/6J mice VO2max and maximal exercise capacity declined with age. At the same absolute and relative workloads, VO2 was lower in AGED mice.
A Unified Mechanism for Abiotic Adenine and Purine Synthesis in Formamide

The synthesis of purines through dehydration and condensation of formamide is a potential abiotic source of nucleobases. It has been reported since the 1950s that heating formamide to near boiling generates purine in high yield (> 70%). The scope of this formamide condensation has been broadened by the identification of multiple biologically relevant products, including nucleobases and amino acid derivatives, from both neat andmineral-doped formamide. Mechanistic pathways to purines have been proposed, though there are significant variations between routes leading to related products. Herein, data is presented suggesting a common pathway for the abiotic syntheses of both purine and adenine from formamide; the proposed route is also highly reminiscent of the biosynthesis of purine nucleobases (Scheme 1). This is the first evidence suggesting that a glycine derivative is a critical intermediate in purine synthesis from formamide, and that this glycine backbone forms a scaffold for purine ring production in the same orientation as in purine ring biosynthesis. Parallels between nucleobase biosynthesis and plausible abiotic syntheses may allude to the origins of this metabolic pathway. Abiotic nucleobases and their analogues have been identified in meteorites, spark discharge experiments, and hydrogen cyanide (HCN) condensation reactions. Typical laboratory procedures call for one to 15m HCN in aqueous ammonia at 25–70 8C. Analyses of the nonphotochemical, mechanistic route fromHCN to adenine have been conducted by Or , Orgel, and Ferris. Briefly, diaminomaleonitrile (DAMN), a relatively stable HCN tetramer, has been identified as an important intermediate. It provides the ring junction scaffold that subsequently closes to an imidazole and then a bicyclic purine, through reaction with cyanide-derived formamidine (Scheme 2). In aqueous
A taxonomy of hosts visiting friends and relatives

Abstract Research on the visiting friends and relatives market, which has increased over the last decade, has focused on the demand side (tourists), ignoring the supply side (hosts). This study fills an apparent gap in the literature by analyzing local residents’ characteristics and behaviors. A taxonomy of hosts was developed to better understand their role and involvement in tourism. Random-dial, structured telephone interviews were undertaken to examine their patterns and behavior. Four types were revealed via cluster analysis based on hosting frequency and word-of-mouth behavior. Residents were further profiled using behavioral and demographic variables. Additionally, the economic impact of hosts’ “tourist-like” spending was calculated.
A model for porosity evolution during creep compaction of sandstones

Abstract A coupled creep-compaction and chemical-reaction model is developed to predict the porosity evolution for quartzose sandstones as a function of strain. The model also demonstrates the relative importance of grain-contact dissolution and cementation for both uniaxial and isotropic compaction. Theoretical analysis indicates that porosity reduction during compaction of sandstones is nonlinearly related to strain. In open systems, porosity loss is also related to grain packing, stress state, and pore-fluid saturation state. Grain-contact dissolution is the dominant mechanism for porosity loss in a closed system and, with increasing compaction, cementation becomes increasingly important. Compared to uniaxial compaction, isotropic compaction leads to more porosity loss due to grain-contact dissolution, but less porosity loss due to cementation. With compaction, pore-fluid saturation state has an increasing effect on porosity loss. Higher saturation state enhances porosity loss due to cementation.
Coding of olfactory information : topography of odorant receptor expression in the catfish olfactory epithelium

Discrimination among the vast array of odors requires that the brain discern which of the numerous odorant receptors have been activated. If individual olfactory neurons express only a subset of the odorant receptor repertoire, then the nature of a given odorant can be discerned by identifying which cells have been activated. We performed in situ hybridization experiments demonstrating that individual olfactory neurons express different complements of odorant receptors and are therefore functionally distinct. Thus, a topographic map, defining either the positions of specific neurons in the epithelium or the positions of their projections, may be employed to determine the quality of an olfactory stimulus. Neurons expressing specific receptors appear to be randomly distributed within the olfactory epithelium. These data are consistent with a model in which randomly dispersed olfactory neurons with common receptor specificities project to common glomeruli in the olfactory bulb.