cssi/SciSciGPT-SciSciNet huggingface dataset:
Experimental study of the instability of unequal-strength counter-rotating vortex pairs

A rapidly growing instability is observed to develop between unequal-strength counter- rotating vortex pairs. The vortex pairs are generated in a towing tank in the wakes of wings with outboard triangular flaps. The vortices from the wing tip and the inboard tip of the flap form the counter-rotating vortex pair on each side of the wing. The flow fields are studied using flow visualization and particle image velocimetry. Both chord- based and circulation-based Reynolds numbers are of O(105). The circulation strength ratios of the flap- to tip-vortex pairs range from −0.4 to −0.7. The initial sinuous stage of the instability of the weaker flap vortex has a wavelength of order one wing span and becomes observable in about 15 wing spans downstream of the wing. The nearly straight vortex filaments first form loops around the stronger wing-tip vortices. The loops soon detach and form rings and move in the wake under self-induction. These vortex rings can move to the other side of the wake. The subsequent development of the instability makes the nearly quasi-steady and two-dimensional wakes unsteady and three-dimensional over a distance of 50 to 100 wing spans. A rectangular wing is also used to generate the classical wake vortex pair with the circulation ratio of −1.0, which serves as a reference flow. This counter-rotating vortex pair, under similar experimental conditions, takes over 200 spans to develop visible deformations. Velocity, vorticity and enstrophy measurements in a fixed plane, in conjuction with the flow observations, are used to quantify the behaviour of the vortex pairs. The vortices in a pair initially orbit around their vorticity centroid, which takes the pair out of the path of the wing. Once the three-dimensional interactions develop, two-dimensional kinetic energy and enstrophy drop, and enstrophy dispersion radius increases sharply. This rapid transformation of the wake into a highly three-dimensional one offers a possible way of alleviating the hazard posed by the vortex wake of transport aircraft.
Neighborhood Social Processes, Physical Conditions, and Disaster-Related Mortality: The Case of the 1995 Chicago Heat Wave

The authors draw on Klinenberg's (2002) ethnography and recent neighborhood theory to explain community-level variation in mortality during the July 1995 Chicago heat wave. They examine the impact of neighborhood structural disadvantage on heat wave mortality and consider three possible intervening mechanisms: social network interaction, collective efficacy, and commercial conditions. Combining Census and mortality data with the 1995 Project on Human Development in Chicago Neighborhoods Community Survey and Systematic Social Observation, the authors estimate hierarchical Poisson models of death rates both during the 1995 heat wave and comparable, temporally proximate July weeks (1990-94, 1996). They find that neighborhood affluence was negatively associated with heat wave mortality. Consistent with Klinenberg's ethnographic study of the Chicago heat wave, commercial decline was positively associated with heat wave mortality and explains the affluence effect. Where commercial decline was low, neighborhoods...
Whose Golden Age? Some Thoughts on Jewish-Christian Relations in Medieval Iberia

The medieval period in Spanish history has alternately been cast as a Golden Age of interfaith harmony and an example of the ultimate incompatibility of Muslim, Christian, and Jewish communities. In this essay, I suggest that a better way to understand interfaith relations in medieval Iberia is to think about these religious communities in less monolithic terms. With regard to Jewish-Christian relations in particular, factors such as wealth, social standing, and intellectual interests were as important as religious identity in shaping the complex bonds between Christians and Jews.
Practical problems in sliding scale autonomy : A case study

Sliding scale autonomy has been suggested as a practical way of organizing robot controls. In this paper, we investigate practical problems in sliding scale autonomy. We take a constructionist approach of building systems with sliding scale autonomy and identifying the challenges involved. We implement robot systems capable of operating semi-autonomously with user guidance. We describe the techniques used to construct the system, the problems discovered along the way, and the improvements achieved. We discuss key parts of two robotic systems we have constructed. We describe our user interface, obstacle avoidance, and localization as implemented on the robot systems.
Urban stress in China

The stress-distress model is examined in the context of a Chinese urban center, Tianjin. Conceptually, the relationship between stress (as reflected in life events) and distress (as reflected in depressed symptoms) is hypothesized to hold across societies. At the same time, the measures of stress must reflect the social reality of a particular community of society. In the case of urban China, the politically-imposed stratification system arranges individuals and family lives around work units. These work units dictate all aspects of the life of the worker and his or her family, ranging from housing, major purchases, access to local and distance facilities, schooling and employment for children, to retirement pension and funeral expenses. As a result, relationships in the work context are expected to produce stress-inducing conflicts. Results from a community survey of Tianjin residents in 1986 support both the generality of the stress-distress model and the specificity of the effects of work-related stressors.
Preoperative and Postoperative Echocardiographic Studies of Pulmonic Valvular Endocarditis

The echocardiographic manifestations of pulmonic valvular endocarditis in a patient with underlying heart disease consisting of a ventricular septal defect and infundibular stenosis are reported. The abnormal shaggy echoes observed on the pulmonic valve were confirmed to be vegetations based on surgical and pathologic findings. This was further proven by the disappearance of the shaggy echoes after surgical excision of the vegetations. We conclude that echocardiograms can detect the presence and disappearance of pulmonic valvular vegetations, which may be of aid in the diagnosis of pulmonic valvular endocarditis.
Hepatitis B vaccines

Abstract Hepatitis B is endemic in many African, Asian and Pacific countries causing much debilitation and death. The disease can lead to chronic cirrhosis and is closely associated with liver cell cancer. There are in the order of 200 million people that carry the virus and constitute a huge reservoir of infection. This latent infection and the combination of a long incubation period (20–180 days), together with the increasing volume and speed of international travel have contributed to make this disease a serious health problem in non-endemic areas. At particular risk are medical and para-medical staff in contract with human blood (especially those concerned with haemodialysis units), dentists, homosexuals, haemophiliacs, patients and staff in mental hospitals and recipients of blood transfusions or other blood products.
This is Definitely Specific: Specificity and Definiteness in Article Systems

This paper argues for the reality of specificity as noteworthiness, a concept built upon Fodor and Sag’s (1982) view of referentiality. Support for this view of specificity comes from the behavior of indefinite this in spoken English, as well as from specificity markers in Samoan, Hebrew, and Sissala. It is shown that the conditions on the use of this-indefinites cannot be accounted for by previous analyses of specificity. The relationship between definiteness and specificity in article systems crosslinguistically is examined, and a distinction between presuppositions and felicity conditions is argued for. Additional evidence for the reality of specificity comes from a study of article choice in the English of adult second language learners (whose L1s, Russian and Korean, lack articles). It is shown that the learners’ errors are tied to specificity: they consist largely of overuse of the in specific indefinite contexts, and overuse of a in non-specific definite contexts. It is concluded that specificity is a universal semantic distinction, which receives morphological expression crosslinguistically and is available to second language learners.
Wall Drag in Internal Mach-2 Flow with Cavity and Transpiration Injection

A drag-measurement facility was used to evaluate potential scramjet fuel-injection/wall-cooling cone gurations. Mach-2aire owcontainingatrainofweak,unsteady,ree ectingshockswassuppliedtotestplatesequippedwithforce and static-pressureinstrumentation. Anonporouse atplate,apartially porouse atplate,anda wallcavityplate (the latter two with mass injection ) were tested. The nonporous plate results were within 10% of both theoretical and numerical predictions. Theporousplateexhibited reduced drag (relative to thenonporous e at plate ), even without mass addition, caused by pressure equalization across the impinging shocks. Addition of mass decreased the drag 46%relativetothee at-platevalue.Therectangularwallcavityhadageometricaspectratio (lengthine owdirection to depth)of 5.0. The cavity plate produced thehighest drag of the cases tested. Without secondary injection cavityplate drag exceeded the instrumentation range, but was estimated as higher than the e at plate by approximately one order of magnitude. A minimum amount of secondary e ow injected into the cavity reduced the drag to a value 50% higher than the e at plate. Further cavity mass addition increased the drag. The porous e at plate provided drag reduction, whereas the cavity cone guration demonstrated drag penalties when compared to the e at plate.
Some Observations on Frequency of Respirator Fit Tests

Quantitative respirator fit tests were repeated with workers who had demonstrated adequate fit initially. As the interval between first and second tests increased, it was expected that the rate of failure (penetration of test aerosol greater than 1%) on the second test also would increase. No significant time relationship was demonstrated, but the results suggest that the opposite of our expectation occurred: failure rates decreased with longer time intervals. If confirmed, the results suggest a simple strategy for repeat fit testing.
Inpatient Diabetes Care: Strategies for Disease Management

Diabetes is a chronic condition with high morbidity, mortality, and prevalence rates that results in high human and financial costs. Coordinating diabetes care with a disease management approach th...
Studies on the mechanism of action of carbamate kinase.

Abstract A procedure for the preparation of a very active carbamate kinase is presented. The reproducibility of the purification procedure and some of the kinetic parameters of the enzymatic reaction have been studied. The preparations are essentially homogeneous in the ultracentrifuge, and have an s20,w of 3.92·10−13; if a molecular weight of 70 000 is assumed, the turnover number approaches 91000 at 38°. The purest preparations are essentially free of biotin, and are not inhibited by avidin. Exchange experiments with 32P-labeled carbamyl phosphate fail to reveal evidence of a phospho-enzyme intermediate. It is concluded that the mechanism of the reaction does not involve biotin or phospho-enzyme formation.
Random-amplified-polymorphic DNA markers in sorghum.

Conditions have been identified that allow reproducible amplification of RAPD markers in sorghum. High resolution of RAPD markers was accomplished by radiolabeling PCR-amplified DNAs followed by separation on denaturing 5% polyacrylamide gels. Reaction parameters including MgCl2 concentration and temperature significantly influenced yield and the type of amplification products synthesized. Unexplained amplified DNAs increased when more than 35 cycles of PCR amplification were used. Under standard conditions, approximately 80% of the primers tested amplified DNA, and most revealed 1–5 polymorphisms between BTx 623 and IS 3620C. Primers were used to amplify RAPDs in 32 genotypes of sorghum. In addition, 8 primers detected RAPDs in a population previously used to create an RFLP map for sorghum. These RAPDs were mapped successfully using a population of 50 F2 plants.
Signal detection and threshold measures to loud tones and radiant heat in chronic low back pain patients and cohort controls

Eleven chronic low back pain (CLBP) and 11 age- and sex-matched control subjects were tested during two separate sessions for the perception of radiant heat and uncomfortably loud tones. Following the determination of a subject's pain threshold (PT) for radiant heat, a standard signal detection methodology was used to present 26 trials each of 4 stimulus levels. The stimuli were rated on a 9-point scale ranging from 'nothing' to 'very strong pain.' A similar procedure was used for the tone stimuli with the 9-point scale ranging from 'nothing' to 'very strongly uncomfortable.' It was found that the CLBP group had both higher heat pain and tone discomfort thresholds than the control group. For radiant heat only, the CLBP group had poorer discrimination as determined by P(I). The results are discussed within the framework of the hypervigilance and adaptation theories of pain perception.
Generalizability theory analysis of balance error scoring system reliability in healthy young adults.

Abstract Context: An assessment of postural control is commonly included in the clinical concussion evaluation. Previous investigators have demonstrated learning effects that may mask concussion-in...
Percutaneous dilation tracheotomy in intensive care unit patients

Objectives In our department, we routinely use percutaneous dilation tracheotomy (PDT) in select intensive care unit (ICU) patients requiring prolonged intubation and mechanical ventilation. We present our experience with this technique and discuss the pros and cons of PDT in the intensive care setting. Study Design and Setting We conducted a retrospective study of consecutive PDTs performed in our institution between 2002 and 2004. Demographic information and procedural and postoperative complications were noted. Results Two hundred seventy-four PDTs were performed on intensive care unit patients during this time period. Complications included five cases of excessive intraoperative bleeding (1.8%), one postoperative hemorrhage (0.3%), one tracheoesophageal fistula (0.3%), one pneumothorax (0.3%), and four accidental decannulations (1.4%). No PDT-associated deaths occurred. Conclusions PDT is advantageous for the patient as it is performed at bedside in the ICU. It is our conclusion that this technique is suitable for many, but not all, critical care patients.
Fetal Heart Rate Monitoring for the Anesthesiologist

..~'ETAL HEART RATE monitoring (FHRM) has become a mainstay of current obstetric practice. After its development in the 1970s as a screening tool for severe intrapartum asphyxia resulting in neurological impairment or death, it was hoped that fetal and neonatal deaths due to intrapartum asphyxia would decrease drastically. Although many well-designed studies have not shown FHRM to be beneficial in reducing these outcomes, the technique is widely used. FHRM, in part, has been blamed for the increase in the rate of cesarean deliveries. The services of an anesthesiologist may be required to provide anesthesia for pregnant women in labor or for obstetric and nonobstetric surgery. In labor, operative vaginal or abdominal delivery may be performed for abnormalities of the fetal heart rate (FHR). Knowledge of FHRM will assist the anesthesiologist in providing optimum care without unnecessarily compromising mother or fetus.
Union negotiations and corporate policy: A study of labor concessions in the domestic steel industry during the 1980s☆

Abstract This paper studies managerial compensation, financial reporting, and dividend policies of the seven major domestic steel producers during requests for union concessions. Substantial layoffs, reported losses, and sacrifices by nonunion stakeholders buttressed managers' case for union concessions. From 1980 to 1988, sample firms reduced their work force by about 300,000 (almost two-thirds) and annual wage payments from $16.1 to $8.6 billion. Reported income is lower during union negotiations, controlling for cash flows, as is managerial pay, with average CEO salary plus bonus declining 18%. Dividend reductions and white-collar pay cuts are substantial, pervasive, and clustered during union negotiations.
Hydrogen selective gas sensor in humid environment based on polymer coated nanostructured-doped tin oxide

Abstract Nanocrystalline indium oxide-doped tin oxide thin film sensors have been synthesized using sol–gel dip-coating technique. The sensors were spin-coated with three different types of polymer namely polymethyl methacrylate (PMMA), poly-perfluorobutenyl vinyl ether (Cytop), fluoropolymer (Fluoropel). The room temperature sensor characteristics (response time, electrical response and recovery time) of the three sensors with different polymer coating were compared at hydrogen concentrations of 600, 1500, 6000 and 15,000 ppm and at two different humidity levels of 14% and 65%. It was found that the polymer coating preserves the selective sensing property of indium oxide-doped tin oxide even at high humidity. The response kinetics of the sensors with different coatings has been compared.
Titration of anthranilic acid with electrolytically generated bromine: Application to coulometric determination of copper

Abstract Anthranilic acid when brominated by electrolytically generated bromine requires 3 moles of bromine per mole. Amperometric detection of the equivalence point is utilised. Small amounts of copper (0.5–2 mg) can be determined by precipitating copper anthranilate, dissolving the precipitate and titrating the liberated anthranilic acid with electrolytically generated bromine.
Flow Field, Turbulent Quantities and Core Stability in Gas-Liquid Two-Phase Swirling Flow: Experiment and Modeling

Compact cyclonic separators are based on swirling flow field, whereby the phases are separated due to the centrifugal forces generated by the flow. This phenomenon is common in several compact separators used by the oil, process and aerospace industries. The objective of this paper is to study experimentally and to develop a model for the hydrodynamics of dispersed two-phase swirling flow, such as present in the lower part of the Gas-Liquid Cylindrical Cyclone (GLCC) or in the Liquid-Liquid Cylindrical Cyclone (LLCC) compact separators. Large amounts of cyclone local measurements of swirling flow data were acquired using an LDV. These data and other published in the literature were used to develop correlations for the swirling flow field and the associated turbulent quantities, based on the swirling intensity concept. The developed correlations can be used to analyze swirling two-phase flow in pipes and cyclonic separators. Finally, an analysis of the gas core stability in the swirling flow field is presented.Copyright © 2003 by ASME
Characteristic and Computational Fluid Dynamics Modeling of High-Pressure Gas Jet Injection

The topic of this paper is the computational modeling of the gas injection process in a large-bore natural gas fueled engine. At high injection pressures, the overall gas injection and mixing process includes compressible flow features such as rarefaction waves and shock formation. The injection geometries examined in the paper include both a two-dimensional slot and an axisymmetric nozzle. The computations examine the effect of the supply pressure/cylinder stagnation pressure ratio, with ratios ranging from 3 to 80, on the velocity and pressure profiles in the near field region. Computational fluid dynamics modeling was compared with results obtained from a two-dimensional analytical method of characteristics solution and experimental results. The comparison process evaluated factors such as pressure and Mach number profiles, jet boundary shape, and shock location.
Infrared Study of NO Adsorption and Reduction with C3H6 in the Presence of O2 over CuO/Al2O3

NO, NO/O2, NO2, and NO2/O2 adsorption on CuO/Al2O3 and selective catalytic reduction (SCR) of NO by C3H6 in the presence of 2% O2 were investigated by infrared spectroscopy coupled with mass spectroscopy to provide insight into the mechanism of NO adsorption and reduction. Adsorption studies show that NO/O2 adsorption at 298–723 K led to rapid formation of Cu2+ N and gradual formation of adsorbed (NO−3)2; NO2/O2 adsorption led to immediate formation of (NO−3)2 and gradual formation of Cu2+-OCu2+-O>N–O, Cu2+ N–O, and Cu2+ N; NO2 adsorption alone did not produce (NO−3)2. Temperature-programmed desorption shows that adsorbed (NO−3)2 decomposed to N2, N2O, and NO at 644 K. Pulsing C3H6 into NO/O2 over CuO/Al2O3 not only removed (NO−3)2 but also reduced Cu2+ to Cu+/Cu0, resulting in the formation of N2, N2O, CO2, and H2O. Steady-state NO/O2/C3H6 reaction on CuO/Al2O3 produced adsorbed C3H7–NO2, CH3COO−, Cu+–NCO, Cu0–CN, and Cu+–CO species, and N2, CO2, and H2O as products. Dynamic behavior of adsorbates under transient conditions suggests that the steady-state SCR reaction may proceed via adsorbed C3H7–NO2, Cu0–CN, and Cu+–NCO intermediates on Cu0/Cu+ surfaces. This study demonstrates that the pulse and steady-state SCR follows different reaction pathways toward N2 and CO2 products.
Band bending at the Si(1 1 1)–SiO2 interface induced by low-energy ion bombardment

Abstract Experiments employing photoreflectance spectroscopy have uncovered band bending due to electrically active defects at the Si(1 1 1)–SiO 2 interface after sub-keV Ar + ion bombardment. The band bending of about 0.5 eV resembles that for Si(1 0 0)–SiO 2 , and both interfaces exhibit two kinetic regimes for the evolution of band bending upon annealing due to defects healing. The healing takes place about an order of magnitude more quickly at the (1 1 1) interface, however, probably because of less fully saturated bonding and higher compressive stress.
Densification of powder rings constrained by dense cylindrical cores

Abstract Alumina rings were slip cast around dense alumina discs, dried and then heated with controlled heating rates to 1550°C. Most specimens developed hair-line, radial cracks that would span the ring due to either drying (differential shrinkage 0.97) at 1550°C as unconstrained rings subjected to an identical heating schedule. Parallel crack-like voids, normal to the tangential tensile stresses developed by constrained densification, and apparently associated with agglomerates, were observed in the constrained rings. Their opening displacement was proportional to the densification strain. Identical, 25 μm, spherical voids introduced into some cast specimens deformed to oblate spheroids consistent with the stress distribution associated with constrained densification. Crack-like voids were also associated with the deformed voids. Radial notches were required to induce macrocracking during constrained densification. Propagation of radial macrocracks initiated at a temperature (1300°C) near the maximum shrinkage strain rate exhibited by the powder compact. They extended with increasing temperature (or density) and their opening displacement was proportional to densification strain. Macrocracking phenomena were independent of heating rate. These results are discussed with relation to damage that might be produced in powder composites by constrained densification and the effect of this damage in reducing densification rates and resulting in end-point densities less than theoretical.
Quantitative Determination of Fluorotelomer Sulfonates in Groundwater by LC MS/MS

Aqueous film-forming foams (AFFF) are complex mixtures containing fluorocarbon- and hydrocarbon-based surfactants that are used to fight hydrocarbon-fueled fires. The military is the largest consumer of AFFF in the United States, and fire-training activities conducted at military bases have led to groundwater contamination by unspent fuels and AFFF chemicals. A direct-injection, liquid-chromatography tandem mass spectrometry (LC MS/MS) method was developed to quantify a suite of fluorotelomer sulfonate surfactants in groundwater collected from military bases where fire-training activities were conducted. The 4:2, 6:2, and 8:2 fluorotelomer sulfonates were detected and quantified in groundwater from two of the three military bases. The total fluorotelomer sulfonate concentrations observed at Wurtsmith AFB, MI, and Tyndall AFB, FL, ranged respectively from below quantitation (< or = 0.60) to 182 microg/L and from 1100 to 14,600 microg/L. Analyses of a fluorotelomer-based AFFF concentrate by negative ion fast atom bombardment/mass spectrometry and LC MS/MS analyses indicate that the AFFF concentrate contains only a small amount of fluorotelomer sulfonates and that fluoroalkylthioamido sulfonates are the main anionic fluorosurfactant in the mixtures. More research is needed to determine the fate of fluoroalkylthioamido sulfonates in the environment.
The Loss of Friends to Homicide and the Implications for the Identity Development of Urban African American Teen Girls

Homicide is the leading cause of death of African American youths in the United States. The loss of their friends to these deaths challenges the identity development of many urban African American teen girls. To understand the implications of such a loss on the psychosocial task of identity development of urban African American teen girls, 21 African American girls, 16–19 years old, living in a large Northeastern city in the United States, participated in a qualitative study. Semi-structured, in-depth interviews were conducted. A grounded theory, constant comparative approach, is used to analyze the narrative data. The findings show (a) the presence and pressure of psychosocial stress on the participants’ identity development process, (b) the adaptive functions of foreclosed religious identity commitments, (c) the potential for this event to inform, in complex ways, racial identity development examined through racial group orientation, and (d) natural avenues of resistance to marginalization and race devaluation that may be experienced from societal responses to this event. How the teens make meaning of this experience informs their identity development. The article promotes the inclusion of identity-informed psychosocial interventions in bereavement work with this population.
Bulge Defects Do Not Destabilize Negatively Supercoiled DNA

The conformational properties of DNA lesions such as extrahelical bulges are presumed to be essential for recognition of defects in DNA structure by a cell's genomic repair machinery. Efficient recognition and repair of lesions by DNA-repair systems occurs despite the wide range of normal heterogeneities in DNA structure, including features such as sequence-dependent bends. The effects of global negative supercoiling on the structure of DNA lesions have been largely unexplored. We have investigated the behavior of several plasmid DNAs containing bulge defects with up to five extrahelical adenine residues. Using two-dimensional agarose-gel electrophoresis, we show that there is no spontaneous cooperative unwinding of these bulge loci up to native levels of negative supercoiling (σ = −0.055) under our conditions.
Propagation of light in metallic nanowire arrays: Finite-difference time-domain studies of silver cylinders

Finite-difference time-domain studies of a variety of silver cylinder arrays with nanometer-scale diameters (nanowires) interacting with light are presented. We show how reasonable estimates of scattering and absorption cross sections for metallic nanoscale objects can be obtained from such calculations. We then study the explicit time-domain behavior of both simple linear chains of such cylinders, as well as more elaborate arrays. A funnel-like configuration is found to be one interesting possibility for achieving propagation of light through features confined in one dimension to less than 100 nm.
Vacancy defects in MgO at high pressure

First-principles calculations within the local density and pseudopotential approximations were performed to investigate the effects of pressure on the energetics and structural behavior of charged vacancy defects in MgO. The simulations were performed for a supercell containing 216 atoms with their positions being fully optimized. In particular, the formation and migration energies of cation and anion vacancies were shown to substantially increase over the pressure regime of the Earth’s mantle. Our results thus suggest that pressure should suppress intrinsic diffusion mediated by ionic vacancies in MgO over the mantle pressure regime. The calculated three-dimensional data sets for atomic displacements and electron charge density were explored in detail using an interactive visualization system. Although the atomic and electronic structures are highly distorted in the close vicinity of the defects (i.e., in the region covering up to the nearest and next-nearest atoms), the effects are not negligible at farther distances.
Quaternary and tertiary quinuclidine derivatives as inhibitors of choline uptake.

Abstract The uptake of choline into cholinergic neurons for acetylcholine (ACh) synthesis is by a specific, high-affinity, sodium- and temperature-dependent transport mechanism (HAChU). Of several quaternary quinuclidinol derivatives tested, the A/-allyl derivative proved to be most potent. Though the methyl, ethyl, and isopropyl derivatives were less potent at comparable concentrations, at higher concentrations they also maximally inhibited HAChU. The benzyl, hydroxyethyl, and methoxyethyl derivatives failed to inhibit HAChU by > 50% at concentrations up to 100 μ M. N -Allyl-3-quinuclidinol (NAQ) proved to be a specific inhibitor of HAChU (IC 50 = 0.9 / μ M) and a poor inhibitor of both sodium-independent transport (IC 50 = 680 /μM) and choline acetyltransferase activity (K, = 200 /μM). The NAQ exhibited noncompetitive type inhibition compared with N -methyl-3-quinuclidinol, a competitive inhibitor of HAChU. Thus, substitution at the N -functional group not only alters potency, but may change the mechanism by which inhibition is produced. The optical isomers of NAQ and several derivatives were prepared and employed to examine the stereochemical selectivity for inhibition of choline uptake. The S(+)-isomer of NAQ(IC 50 = 0.1 μ M) had ~ 100-fold greater inhibitory activity for HAChU than the corresponding (-isomer (ICso = 10 μ M). With all other quinuclidinols tested, the S(+)-isomers were also more potent than the corresponding R(-)-isomers. In an effort to obtain a tertiary inhibitor of HAChU that would be expected to cross the blood-brain barrier following peripheral administration, 3-biphenyl-3-quinuclidinol (BHQ) and 3-naphthyl-3-quinuclidinol (NHQ) were synthesized and evaluated. The BHQ was a fairly potent inhibitor of HAChU (ICso = μ M) which maximally inhibited HAChU at 100 μ M. Its methylated derivative demonstrated a similar profile; in contrast, NHQ only inhibited HAChU by 52% at 100 μ M.
Transcriptome Profiling Identifies HMGA2 as a Biomarker of Melanoma Progression and Prognosis

The genetic alterations contributing to melanoma pathogenesis are incompletely defined, and few independent prognostic features have been identified beyond the clinicopathological characteristics of the primary tumor. We used transcriptome profiling of 46 primary melanomas, 12 melanoma metastases, and 16 normal skin (N) samples to find genes associated with melanoma development and progression. Results were confirmed using immunohistochemistry and real-time PCR and replicated in an independent set of 330 melanomas using AQUA analysis of tissue microarray (TMA). Transcriptome profiling revealed that transcription factor HMGA2, previously unrecognized in melanoma pathogenesis, is significantly upregulated in primary melanoma and metastases (P-values=1.2 × 10−7 and 9 × 10−5) compared with N. HMGA2 overexpression is associated with BRAF/NRAS mutations (P=0.0002). Cox proportional hazard regression model and log-rank test showed that HMGA2 is independently associated with disease-free survival (hazard ratio (HR)=6.3, 95% confidence interval (CI)=1.8–22.3, P=0.004), overall survival (OS) (stratified log-rank P=0.008), and distant metastases–free survival (HR=6.4, 95% CI=1.4–29.7, P=0.018) after adjusting for American Joint Committee on Cancer (AJCC) stage and age at diagnosis. Survival analysis in an independent replication TMA of 330 melanomas confirmed the association of HMGA2 expression with OS (P=0.0211). Our study implicates HMGA2 in melanoma progression and demonstrates that HMGA2 overexpression can serve as an independent predictor of survival in melanoma.
Native and Non-Native Speakers in Online and Face-to-Face Discussions: Leveling the Playing Field.

This study investigated the role of native language in the context of online versus face-to-face learning environments. Findings from a mixed-methods analysis revealed that native language was a fa...
Rapid recognition of object outlines in reduced resolution images

Abstract In this paper we describe a procedure for rapid determination of object outlines from reduced resolution images. Local edges are determined in both the horizontal and vertical directions from the relative grey levels on either side of the edge. These local edges are connected in groups and the horizontal and vertical edge groups are then linked to form a closed curve. Pattern recognition of the object outline is performed on the curve of averaged successive angular deflection vs position along the outline. Applications of the procedure to robot vision are discussed.
Quantifying violations of destination-based forwarding on the internet

Initially, packet forwarding in the Internet was destination-based -- that is, a router would forward all packets with the same destination address to the same next hop. In this paper, we use active probing methods to quantify and characterize deviations from destination-based forwarding in today's Internet. From over a quarter million probes, we analyze the forwarding behavior of almost 40,000 intermediate routers. We find that, for 29% of the targeted routers, the router forwards traffic going to a single destination via different next hops, and 1.3% of the routers even select next hops in different ASes. Load balancers are unlikely to explain these AS-level variations, and in fact we uncover causes including routers inside MPLS tunnels that otherwise employ default routes. We also find that these violations can significantly affect the results of measurement tools that rely on destination-based forwarding, and we discuss some ideas for making these tools more robust against these violations.
Literacy, Capital, and Education: A View From Immigrant Youth

From conservative estimates, as many as 1 in every 5 schoolchildren is an immigrant. Through both sheer numbers and qualitatively different migration practices, these populations have productively created an opportunity and imperative for educational practice to redefine its assumptions, practices, and relevancy. In this article, the author present snapshots of young immigrants navigating schooling and society, and more specifically, elucidate how these snapshots can productively agitate how literacy educators understand and undertake their work. The article uses case studies of two recently arrived immigrant students to examine how classroom practices and educational policies position these students, how literacy pedagogy follows from that framing, and how those frames obscure the complicated ways that textual practices reflect and structure societal experiences for immigrant youth. It provides recommendations for how educators can revamp their work to create educational experiences considerate of and re...
The inhibition mechanism of guanidine hydrochloride on the catalytic activity of recombinant human protein disulfide isomerase.

Initial velocity enzyme kinetics was used to study the inhibition mechanism of guanidine hydrochloride (Gdm.Cl) on catalytic activity of recombinant human protein disulfide isomerase (rhPDI) in protein folding. Reduced C125A recombinant human interleukin 2 (C125A rhIL-2), the substrate, was dissolved in 8 M Gdm.Cl before it was diluted into the folding buffer to initiate the folding reactions. The final Gdm.Cl concentrations in the folding buffer were fixed at 0.2 M, 0.4 M, 0.6 M and 0.8 M. The reduced and native C125A rhIL-2 were resolved by reversed phase-high performance liquid chromatography (RP-HPLC). The simultaneous nonlinear fitting of the initial velocities of the native C125A rhIL-2 formation vs the reduced C125A rhIL-2 concentrations in the presence of different Gdm.Cl concentrations shows that the inhibition mechanism of Gdm.Cl on the catalytic activities of rhPDI is a mixed-type noncompetitive nonlinear inhibition.
Virtual histology of the human heart using optical coherence tomography

Optical coherence tomography OCT allows for the visu- alization of micron-scale structures within nontransparent biological tissues. For the first time, we demonstrate the use of OCT in identify- ing components of the cardiac conduction system and other structures in the explanted human heart. Reconstructions of cardiac structures up to 2m mbelow the tissue surface were achieved and validated with Masson Trichrome histology in atrial, ventricular, sinoatrial nodal, and atrioventricular nodal preparations. The high spatial reso- lution of OCT provides visualization of cardiac fibers within the myo- cardium, as well as elements of the cardiac conduction system; how- ever, a limiting factor remains its depth penetration, demonstrated to be 2m min cardiac tissues. Despite its currently limited imaging depth, the use of OCT to identify the structural determinants of both normal and abnormal function in the intact human heart is critical in its development as a potential aid to intracardiac arrhythmia diagnosis
Refining Biodiversity Conservation Priorities

Although there is widespread agreement about conservation priorities at large scales (i.e., biodi- versity hotspots), their boundaries remain too coarse for setting practical conservation goals. Refining hotspot conservation means identifying specific locations (individual habitat patches) of realistic size and scale for managers to protect and politicians to support. Because hotspots have lost most of their original habitat, species endemic to them rely on what remains. The issue now becomes identifying where this habitat is and these species are. We accomplished this by using straightforward remote sensing and GIS techniques, identifying specific locations in Brazil's Atlantic Forest hotspot important for bird conservation. Our method requires a regional map of current forest cover, so we explored six popular products for mapping and quantifying forest: MODIS continuous fields and a MODIS land cover (preclassified products), AVHRR, SPOT VGT, MODIS (satellite images), and a GeoCover Landsat thematic mapper mosaic ( jpg). We compared subsets of these forest covers against a forest map based on a Landsat enhanced thematic mapper. The SPOT VGT forest cover predicted forest area and location well, so we combined it with elevation data to refine coarse distribution maps for forest endemic birds. Stacking these species distribution maps enabled identification of the subregion richest in threatened birds—the lowland forests of Rio de Janeiro State. We highlighted eight priority fragments, fo- cusing on one with finer resolved imagery for detailed study. This method allows prioritization of areas for conservation from a region >1 million km 2 to forest fragments of tens of square kilometers. To set priorities for biodiversity conservation, coarse biological information is sufficient. Hence, our method is attractive for tropical and biologically rich locations, where species location information is sparse.
Engaging Probability Students in Playing and Analysing a Simple Card Game

Summary We present a simple card game whose payout depends on a player's strategy, as well as on chance. Solutions require the use of conditional analysis and the computation of expected values.
BiMn “spire” growths induced by a magnetic field

Abstract BiMn “spires” or columns of highly oriented ferromagnetic BiMn crystallites have been found to grow out of a mixture of molten Bi and particles of Mn metal. The growth direction is along an applied magnetic field and has occurred both perpendicular to and against the gravitational field. A first mechanism for formation postulates the enhancement of the nucleation probability at the tip of a spire by the high magnetic field present. The second mechanism requires the formation of ferromagnetic BiMn particles throughout the molten Bi volume. These particles are then pulled to the spire tip, where they are aligned and subsequently grow by size preference.
T Helper 1 Cells and Interferon γ Regulate Allergic Airway Inflammation and Mucus Production

CD4 T helper (Th) type 1 and Th2 cells have been identified in the airways of asthmatic patients. Th2 cells are believed to contribute to pathogenesis of the disease, but the role of Th1 cells is not well defined. In a mouse model, we previously reported that transferred T cell receptor–transgenic Th2 cells activated in the respiratory tract led to airway inflammation with many of the pathologic features of asthma, including airway eosinophilia and mucus production. Th1 cells caused inflammation with none of the pathology associated with asthma. In this report, we investigate the role of Th1 cells in regulating airway inflammation. When Th1 and Th2 cells are transferred together into recipient mice, there is a marked reduction in airway eosinophilia and mucus staining. To address the precise role of Th1 cells, we asked (i), Are Th2-induced responses inhibited by interferon (IFN)-γ? and (ii) Can Th1 cells induce eosinophilia and mucus in the absence of IFN-γ? In IFN-γ receptor−/− recipient mice exposed to inhaled antigen, the inhibitory effects of Th1 cells on both airway eosinophilia and mucus production were abolished. In the absence of IFN-γ receptor signaling, Th1 cells induced mucus but not eosinophilia. Thus, we have identified new regulatory pathways for mucus production; mucus can be induced by Th2 and non-Th2 inflammatory responses in the lung, both of which are inhibited by IFN-γ. The blockade of eosinophilia and mucus production by IFN-γ likely occurs through different inhibitory pathways that are activated downstream of Th2 cytokine secretion and require IFN-γ signaling in tissue of recipient mice.
Algebras with nondegenerate associative symmetric bilinear forms permitting composition, II

(1981). Algebras with nondegenerate associative symmetric bilinear forms permitting composition. Communications in Algebra: Vol. 9, No. 12, pp. 1233-1261.
Basis for Improved Permeability Barrier Homeostasis Induced by PPAR and LXR Activators: Liposensors Stimulate Lipid Synthesis, Lamellar Body Secretion, and Post-Secretory Lipid Processing

Previously, we demonstrated that topical applications of peroxisome proliferator-activated receptors (PPARs) and liver X receptor (LXR) activators improve permeability barrier homeostasis. We showed further that stimulation of epidermal differentiation provides one mechanism that could account for such improvement. Here, we studied the effects of these agents on the lipid matrix of the stratum corneum. Hairless mice were treated topically with activators of PPARα (WY14643), PPARδ (GW1514), PPARγ (ciglitazone), and LXR (22(R)-cholesterol or TO901317) or vehicle twice daily for 3 days. All activators significantly increased epidermal cholesterol, fatty acid, and sphingolipid synthesis, including the production of barrier-specific ceramide species. In addition, lamellar body (LB) formation, secretion, and post-secretory processing accelerated significantly following acute barrier disruption in PPAR/LXR-activator-treated animals. Finally, the activity of epidermal β-glucocerebrosidase, a key lipid-processing enzyme, increased in PPAR/LXR-activator-treated animals. Thus, topical PPAR and LXR activators stimulate epidermal lipid synthesis, increase LB secretion, and accelerate extracellular lipid processing, providing additional mechanisms that further account for their ability to improve epidermal permeability barrier homeostasis. Since the liposensors are activated by endogenous lipid metabolites, they may serve as unique regulators of barrier homeostasis.
Altering State Policy: Interest Group Effectiveness among State-Level Advocacy Groups

Because social policy making continues to devolve to the state level, social workers should understand how advocacy and policy making occur at that level. Interest groups active in the human services arena were surveyed and data were used to test a model of interest group effectiveness in four states. The independent variables were amount of resources invested, strategy used, relationships with key actors, use of coalitions, and policy positions taken. Results indicate that the model explains low to middling amounts of the variation in group effectiveness. Results also show that the model fits different states to different degrees, indicating that social workers need to approach advocacy in different ways to achieve maximum effectiveness in altering state policy. Implications for altering state policy are provided.
Cooptation and cooperation: institutional exemplars of democratic internet technology

This article examines how online political groups are co-opting internet technology from commercial interests to amplify various cooperative processes. After formulating a framework for praxis-based democratic theories of technology, I select four internet-based groups as institutional exemplars for analysis: Democratic Underground, Free Republic, Indymedia, and Move On. These groups implement distinct types of democratic applications of internet technology and embody specific strands of democratic theory. I conclude by commenting on the direction of internet-based democratic practices, their political efficacy in terms of strategy and tactics, and how they figure within US political culture.
AMOUR-generalized multicarrier CDMA irrespective of multipath

The suppression of multiuser interference (MUI) and mitigation of multipath effects constitute major challenges in the design of third-generation wireless mobile systems. Most wideband and multicarrier uplink CDMA schemes suppress MUI statistically in the presence of unknown multipath and impose restrictive and difficult to check conditions on the FIR channel nulls. Relying on symbol blocking, we design a mutually-orthogonal usercode-receiver (AMOUR) system for quasi-synchronous blind CDMA that eliminates MUI deterministically and mitigates fading irrespective of the unknown multipath and the adopted signal constellation. AMOUR converts a multiuser CDMA system into parallel single-user systems irrespective of multipath and guarantees identifiability of users' symbols. Simulations reveal the generality, flexibility, and superior performance of AMOUR over competing alternatives.