cssi/SciSciGPT-SciSciNet huggingface dataset:
Serum IgE measurement and detection of food allergy in pediatric patients with eosinophilic esophagitis

Background Although associated allergies are common and the mechanism may include long-term exposure to allergens, measurement of serum specific IgE levels has not been studied in pediatric eosinophilic esophagitis (EE). Objective To compare the results of serum IgE testing, patch testing, and epicutaneous skin testing to measure allergic sensitization in pediatric patients with EE. Methods In a cross-sectional study of 53 pediatric patients with EE, relevant history was obtained by questionnaire, and patch testing to foods was performed. Food and inhalant sensitivities were also assessed using skin prick testing and serum specific IgE measurement. Streptavidin CAP was used to measure specific IgE to cross-reactive carbohydrate determinants and Helicobacter pylori . Results The overall prevalence of food and inhalant sensitization was 80%, with higher total IgE levels in sensitized vs nonsensitized patients (median, 150 vs 13 IU/mL; P P = .001). Patch test results were interpreted as positive in 39% of patients (rye, wheat, and soy were the most common). Conclusions Most, but not all, patients with EE are highly atopic individuals with frequent allergic sensitivities. Thus, serum IgE measurement of low-titer IgE antibody may be useful in identifying relevant food sensitivities and in distinguishing subgroups of patients with EE, making a more directed approach to food avoidance possible.
Reversible water-solubilization of single-walled carbon nanotubes by polymer wrapping

Abstract Single-walled carbon nanotubes (SWNTs) have been solubilized in water by non-covalently associating them with linear polymers, most successfully with polyvinyl pyrrolidone (PVP) and polystyrene sulfonate (PSS). This association is characterized by tight, uniform association of the polymers with the sides of the nanotubes. A general thermodynamic drive for this wrapping is discussed, wherein the polymer disrupts both the hydrophobic interface with water and the smooth tube–tube interactions in aggregates. The nanotubes can be unwrapped by changing the solvent system. This solubilization process opens the door to solution chemistry on pristine nanotubes, as well as their introduction into biologically relevant systems.
Propeller/wing interaction

The present experimental investigation of the steady-state and unsteady-state effects due to the interaction between a tractor propeller's wake and a wing employs, in the steady case, wind tunnel measurements at low subsonic speed; results are obtained which demonstrate wing performance response to variations in configuration geometry. Other steady-state results involve the propeller-hub lift and side-force due to the wing's influence on the propeller. The unsteady effects of interaction were studied through flow visualization of propeller-tip vortex distortion over a wing, again using a tractor-propeller configuration.
Cationic poly(VCL–AETA) hydrogels and ovalbumin (OVA) release in vitro

The objective of this research is to explore the synthesis of a new family of water soluble polycationic copolymeric precursors that could be photo-crosslinked into hydrogels. The in vitro control release of ovalbumin protein (OVA) from this family of hydrogels was also studied to assess the biomedical potential of this new family polycationic hydrogels. A series of novel poly(VCL-AETA) copolymer hydrogels was fabricated in an aqueous medium via photo-induced polymerization and crosslinking of hydrophobic N-vinylcaprolactam (VCL) and hydrophilic [2-(acryloxy)ethyl]trimethylammonium chloride (AETA) monomers over a wide range of VCL to AETA feed molar ratios of 2:1, 1:1, 1:2, 1:5. N,N'-methylene bisacrylamide (MBA) was used as a crosslinker. Ovalbumin (OVA), a model antigen, was preloaded into poly(VCL-AETA) hydrogel precursors and its release profiles in pH 7.4 PBS at 37 degrees C were investigated as a function of VCL to AETA monomer feed ratios over a period of 4 weeks. The in vitro results showed that OVA initial burst and subsequent sustained releases could be controlled by 3 material parameters: the hydrophobic VCL to hydrophilic AETA monomer feed ratios, crosslinking density and hydrogel degradation rate. Thus, the hydrophobic-hydrophilic VCL-AETA hydrogel network for controlled OVA release could offer advantages over organic solvent-based single component polymer system. However, these in vitro OVA release profiles may change in an in vivo environment.
The Local Politics and Partnerships of Successful Welfare Reform at Modesto Junior College.

In order for community colleges to fulfill their role in welfare reform, careful attention must be paid to internal and external constituencies. This chapter describes how Modesto Junior College built partnerships based on trust and mutual respect that led to success for welfare recipients.
Intra-Party Political Debates and Issue Learning.

This study examined issue learning outcomes in three intra‐party political debates during the 1984 campaign for the Democratic presidential nomination. The results indicated that intra‐party political debates produce significant viewer learning (1) about the issue positions of each participating candidate, (2) about most issues, and (3) among all categories of viewers. In addition, the study found that intra‐party political debates produce distinct outcomes, including: variation in learning between debates about candidate positions on particular issues; significant increases in learning about the positions of the Democratic candidates on the part of Democratic, Republican, and nonaffiliated viewers; and a negative effect on viewer knowledge about nonparticipating incumbent Ronald Reagan's positions on the issues.
E1-E2 Interactions in Ubiquitin and Nedd8 Ligation Pathways

Initial rates of E1-catalyzed E2 transthiolation have been used as a reporter function to probe the mechanism of 125I-ubiquitin transfer between activation and ligation half-reactions of ubiquitin conjugation. A functional survey of 11 representative human E2 paralogs reveals similar Km for binding to human Uba1 ternary complex (Km(ave) = 121 ± 72 nm) and kcat for ubiquitin transfer (kcat(ave) = 4.0 ± 1.2 s−1), suggesting that they possess a conserved binding site and transition state geometry and that they compete for charging through differences in intracellular concentration. Sequence analysis and mutagenesis localize this binding motif to three basic residues within Helix 1 of the E2 core domain, confirmed by transthiolation kinetics. Partial conservation of the motif among E2 paralogs not recognized by Uba1 suggests that another factor(s) account for the absolute specificity of cognate E2 binding. Truncation of the Uba1 carboxyl-terminal β-grasp domain reduces cognate Ubc2b binding by 31-fold and kcat by 3.5 × 104-fold, indicating contributions to E2 binding and transition state stabilization. Truncation of the paralogous domain from the Nedd8 activating enzyme has negligible effect on cognate Ubc12 transthiolation but abrogates E2 specificity toward non-cognate carrier proteins. Exchange of the β-grasp domains between ubiquitin and Nedd8 activating enzymes fails to reverse the effect of truncation. Thus, the conserved Helix 1 binding motif and the β-grasp domain direct general E2 binding, whereas the latter additionally serves as a specificity filter to exclude charging of non-cognate E2 paralogs in order to maintain the fidelity of downstream signaling.
Characterization of NiTiNOL for Smart Structural Systems using ACES Methodology

SMAs are engineering alloys that recover extensive amounts of deformation when subjected to a temperature change. The recovery of deformation is as result of a phase transformation from martensite to austenite. For example, for NiTiNOL, a very popular SMA, this transformation occurs at 60°C. Actuation is a type of shape memory process that utilizes deformation recovery that is used in smart structural systems. These systems are designed to detect and control structural deformations due to external time varying loads encountered during functional operation. In this paper, the actuating properties of NiTiNOL are characterized using an analytical, computational, and experimental solution (ACES) methodology. Analytical models are utilized to calculate the deformation under dynamic loads. Finite element method (FEM) is used for computational investigations. Optoelectronic holography (OEH) is the experimental method utilized to obtain temperature dependent behavior of NiTiNOL. As a result of the phase transformation, NiTiNOL undergoes a stiffness change indicated by a change in the modulus of elasticity from 33 GPa to 75 GPa. Deformations of NiTiNOL samples subjected to static loads at different temperatures were measured indicating recovery of 85% due to the phase transformation. In addition, amplitudes of vibration were measured as a function of excitation frequency and temperature to determine the effects of phase transformation. The results show effectiveness of NiTiNOL in development of smart structural systems
Phase behavior of aqueous two-polymer systems

Abstract In this work we consider the thermodynamic description of the liquid-liquid phase behavior of dextran-polyethylene glycol-water systems which are of interest for biological separations. In this effort, we use the Flory-Huggins and UNIQUAC models, and develop a new numerical procedure to estimate the interaction parameters. Also, when using interaction parameters for the Flory-Huggins model obtained from osmotic pressure and plait point data, qualitatively reasonable binodal curves were obtained. Due to the asymmetry in the experimental binodal curves for these polymer systems, there is a small difference between the calculated interaction parameters for each of the polymers with water. The location of a binodal curve is found to be sensitively dependent on the interactions between the unlike polymers. Multiple sets of interaction parameters were found for the UNIQUAC model which could describe liquid-liquid phase splitting in a reasonable manner. In particular, an intercorrelation was found in which any set of parameters in a broad range could predict the phase behavior equally well. Also, the volume and surface area parameters of the polymers were found to play an important role in determining phase behavior of these polymer systems. The shift of the binodal curve with molecular weight of the polymers was also investigated.
Influence of intravesicular pH drift and membrane binding on the liposomal release of a model amine-containing permeant

Accurate determination of intrinsic permeability coefficients is critical to the development of structure-permeability relationships and liposomal delivery systems. The apparent release rate of a drug from liposomes may reflect not only its intrinsic permeability coefficient and barrier properties but also a variety of underlying equilibria including drug ionization, membrane binding or complexation, and kinetic processes such as buffer exchange. Additionally, transport of ionizable drugs that are initially at high concentrations in liposomes can generate or dissipate pH gradients across the barrier causing deviations from classical pH-permeability profiles. In this study, the liposomal release of a model amine (tyramine) is determined as a function of drug loading, intravesicular pH, and buffer composition. Kinetic models are derived to study effects of such equilibria (e.g., ionization, membrane binding) and kinetic processes (e.g., pH drift and acid/base carriers). All equilibrium constants needed for the models were independently measured and used. The barrier properties of the lipid bilayers under the experimental conditions were assessed by monitoring the transport of mannitol and bretylium as a function of pH. A corrected intrinsic permeability coefficient of 0.04 cm/s was in close agreement with the value predicted from the barrier domain model for bilayer permeability, suggesting that all perturbing factors were properly addressed.
Effects of an inpatient geriatrics rotation on internal medicine residents' knowledge and attitudes

OBJECTIVE: The purpose of this study is to assess the effect of a geriatrics-focused acute medicine inpatient rotation and the presence or absence of a geriatrician as attending physician on knowledge about and attitudes toward older patients and the field of geriatrics.
The innervation and chemical sensitivity of single aesthetasc hairs

Each aesthetasc hair of the lateral antennule of the California spiny lobsterPanulirus interruptus (Randall) is shown by light and scanning electron microscopy to be innervated by a basally situated cluster of sensory neurons encased in a glial sheath which isolates each cluster from those of other hairs (Figs. 1, 3, 4). The dendrites of these neurons penetrate the aesthetasc hairs and their axons extend to the central nervous system. Extracellular recordings with suction electrodes from the axons of single neuronal clusters were used to determine the responsiveness of individual hairs to a spectrum of amino acids, amines, amides, carbohydrates, carboxylic acids, nucleotides, and a tripeptide (Tables 1, 2, Figs. 6, 8). Randomly selected hairs from the antennules of juvenile, and male and female adult lobsters were shown to be broadly sensitive to a variety of stimuli and are homogeneous in their breadth of responsiveness (Figs. 5, 7). Cluster analysis does not reveal distinct chemoreceptive hair types based on their response spectra, suggesting that the receptor populations of single hairs are uniformly competent to respond to diverse chemical stimuli (Figs. 6, 8). Further, the sensitivity profile of aesthetascs to these stimuli correlates well with behavioral responses ofPanulirus interruptus to these same stimuli (Tables 1, 2).
Structural investigation of helices II, III, and IV of B. megaterium 5S ribosomal RNA by molecular dynamics calculations.

The structures of the helices II-III region and the helix IV region of B. megaterium 5S rRNA have been examined by means of energy minimization and molecular dynamics calculations. Calculated distances between neighboring hydrogen-bonded imino protons in helices II, III, and IV were between 3.5 and 4.5 A. The overall axis for the helices II-III region is warped rather than straight. Formation of additional Watson-Crick base pairs in loop B and loop C was not evident from the atomic positions calculated by molecular dynamics. Bases in loop C are well stacked, showing no significant change during dynamics. Bulge migration in helix III does not seem to be possible; the helices II-III region prefers one conformation. Helix II is more stable than helix III. Five base pairs in helix IV were sufficiently stable to establish that helix IV is terminated by a hairpin loop of three nucleotides. U87 protrudes from loop D. Structures of the helices II-III segment and the helix IV segment of B. megaterium 5S rRNA obtained by molecular dynamics were generally consistent with the solution structure inferred from high-field proton nmr spectroscopy. © 1992 John Wiley & Sons, Inc.
Mechanism and speed of initial step of oxygen chemisorption-O2 on W

A direct first step in the mechanism for the initial oxidation of a polycrystalline tungsten surface, the catalyzed dissociation of O2 on it, or the formation of WO X by O2 at intermediate temperatures is shown to occur in ∼10−13 s. Molecular beam experiments demonstrated that the reactivity was greater than 90%, the unreacted O2 was substantially unaccommodated in translational energy to the surface temperature, and the reaction probability was nearly independent of surface temperature from 2800 to 415 K although there was a small increase at 415 K. The general conditions when no molecular surface precursor state contributes to the surface reactivity are discussed.
Development of a homogeneous immunoassay for the detection of fentanyl in urine

OBJECTIVE: Fentanyl is an extremely potent synthetic opioid that is widely used for chronic pain treatment; it is highly addictive and prone to abuse. The objective is to develop a high throughput homogeneous enzyme immunoassay (HEIA) for the rapid detection of fentanyl in human urine. METHODS: The HEIA is based on an immunoassay format in which both the antibody and enzyme-drug conjugate are in ready-to-use solution. In the absence of the target analyte in the specimen, enzyme-labeled drug conjugate binds to the antibody and results in a decrease of the enzyme (G6PDH) activity; hence there is lower absorbance at 340nm. If the target analyte is present in the specimen, it competes with the enzyme-labeled drug to bind to limited amount of specific antibody that result in more enzyme activity and yields an increased absorbance at 340nm. A polyclonal "in-house" antibody was selected that is capable of measuring fentanyl at low concentrations thus the assay detection limit was determined to be 1ng/mL. The assay was validated with clinical urine specimens that previously confirmed positively or negatively for fentanyl/norfentanyl by LC-MS/MS. RESULTS: The intra-day (n=20) and inter-day (n=100) precision of the assay was less than 1% CV. No interferences from structurally unrelated and commonly ingested drugs were observed at a concentration of 10,000ng/mL. A total of 209 LC-MS/MS confirmed urine specimens (149 positive and 57 negative samples) were analyzed by HEIA. The sensitivity, specificity, and accuracy values were 99%, 95%, and 98% respectively. CONCLUSION: This paper describes the development of a highly sensitive homogenous enzyme immunoassay for detecting fentanyl in urine at a cut-off concentration of 2ng/mL. Language: en
Sill to surface: Linking young off-axis volcanism with subsurface melt at the overlapping spreading center at 9°03′N East Pacific Rise

Abstract No young, off-axis, mid-ocean ridge lavas have yet been directly linked to underlying off-axis melt bodies. In this study, we present new measurements of 238 U– 230 Th– 226 Ra– 210 Pb isotope compositions for a suite of lavas from the overlapping spreading center (OSC) at 9°03′N on the East Pacific Rise (EPR). These lavas span a large range of compositions, from basalt to dacite, and include both axial and off-axis samples recovered from a prominent, axis-parallel pillow ridge and a flat-topped seamount that overlie the westernmost extent of a 4-km-wide melt lens ( Kent et al., 2000 ). We report 210 Pb excesses in axial basalts and basaltic andesites, which we suggest results from gas-magma fractionation of 222 Rn from 226 Ra beneath dacite magmas. In addition, our U-series ages agree with visual observations, indicating that while most recent volcanic activity occurs at the spreading axis, active volcanism also occurs away from the axis. Specifically, the off-axis pillow ridge and seamount samples overlying the off-axis subsurface melt body have eruption ages of less than 8 ka, and likely as young as 1 ka, despite being located on crust that has a spreading age of ~75 ka. The young ages of these lavas, combined with existing geological, geochemical and geophysical constraints, provide evidence for a genetic link between the pillow ridge and seamount lavas and the seismically imaged, underlying off-axis melt lens. This link demonstrates that off-axis volcanism does not necessarily come from a sub-axial magma body and can be sourced directly from off-axis magma bodies.
Randomized group testing for acoustic source localization

Undersea localization requires a computationally expensive partial differential equation simulation to test each candidate hypothesis location via matched filter. We propose a method of batch testing that effectively yields a test sequence output of random combinations of location-specific matched filter correlations, such that the computational run time varies with the number of tests instead of the number of locations. We show that by finding the most likely location that could have accounted for these batch test outputs, we are able to perform almost as well as if we had computed each location's matched filter. In particular, we show that we can reliably resolve the target's location up to the resolution of incoherence using only logarithmically many measurements when the number of candidate locations is less than the dimension of the matched filter. In this way, our random mask pattern not only performs substantially the same as cleverly designed deterministic masks in classical batch testing scenarios, but also naturally extends to other scenarios when the design of such deterministic masks may be less obvious.
Comparative ESR and Catalytic Studies of Ethylene Dimerization on Pd(II)-Exchanged Clinoptilolite, Mordenite, Ferrierite, and SUZ-4

Catalytic activity for ethylene dimerization is studied in four palladium-exchanged zeolites, PdH-clinoptilolite, PdH-mordenite, PdH-ferrierite, and PdHK-SUZ-4, with different channel systems. The formation and adsorbate interactions of Pd(I) are also investigated for a better understanding of the role of Pd(I) on the catalytic reaction in these zeolites using electron spin resonance (ESR) spectroscopy. Thermal and hydrogen reduction of Pd(II) in clinoptilolite, mordenite, ferrierite, and SUZ-4 produce isolated Pd(I) with somewhat different ESR parameters. The interaction of Pd(I) with various sizes of adsorbates shows some similarities in PdH-mordenite and PdH-ferrierite, indicating that Pd(I) is located in the main 12-ring and 10-ring channels of mordenite and ferrierite, respectively, where all the Pd(I) can coordinate with methanol and pyridine. However, SUZ-4 shows a noticeable difference in the way Pd(I) interacts with several adsorbates such as ammonia, methanol, and ethylene. These adsorbates redu...
Problems Before Solutions: Automated Problem Clarification at Scale

Automatic assessment reduces the need for individual feedback in massive courses, but often focuses only on scoring solutions, rather than assessing whether students correctly understand problems. We present an enriched approach to automatic assessment that explicitly assists students in understanding the detailed specification of technical problems that they are asked to solve, in addition to evaluating their solutions. Students are given a suite of solution test cases, but they must first unlock each test case by validating its behavior before they are allowed to apply it to their proposed solution. When provided with this automated feedback early in the problem-solving process, students ask fewer clarificatory questions and express less confusion about assessments. As a result, instructors spend less time explaining problems to students. In a 1300-person university course, we observed that the vast majority of students chose to validate their understanding of test cases before attempting to solve problems. These students reported that the validation process improved their understanding.
Vigilance on the move: video game-based measurement of sustained attention

Vigilance represents the capacity to sustain attention to any environmental source of information over prolonged periods on watch. Most stimuli used in vigilance research over the previous six decades have been relatively simple and often purport to represent important aspects of detection and discrimination tasks in real-world settings. Such displays are most frequently composed of single stimulus presentations in discrete trials against a uniform, often uncluttered background. The present experiment establishes a dynamic, first-person perspective vigilance task in motion using a video-game environment. ‘Vigilance on the move’ is thus a new paradigm for the study of sustained attention. We conclude that the stress of vigilance extends to the new paradigm, but whether the performance decrement emerges depends upon specific task parameters. The development of the task, the issues to be resolved and the pattern of performance, perceived workload and stress associated with performing such dynamic vigilance a...
Operational Lessons Learned from the Ares I-X Flight Test

The Ares I-X flight test, launched in 2009, is the first test of the Ares I crew launch vehicle. This development flight test evaluated the flight dynamics, roll control, and separation events, but also provided early insights into logistical, stacking, launch, and recovery operations for Ares I. Operational lessons will be especially important for NASA as the agency makes the transition from the Space Shuttle to the Constellation Program, which is designed to be less labor-intensive. The mission team itself comprised only 700 individuals over the life of the project compared to the thousands involved in Shuttle and Apollo missions; while missions to and beyond low-Earth orbit obviously will require additional personnel, this lean approach will serve as a model for future Constellation missions. To prepare for Ares I-X, vehicle stacking and launch infrastructure had to be modified at Kennedy Space Center's Vehicle Assembly Building (VAB) as well as Launch Complex (LC) 39B. In the VAB, several platforms and other structures designed for the Shuttle s configuration had to be removed to accommodate the in-line, much taller Ares I-X. Vehicle preparation activities resulted in delays, but also in lessons learned for ground operations personnel, including hardware deliveries, cable routing, transferred work and custodial paperwork. Ares I-X also proved to be a resource challenge, as individuals and ground service equipment (GSE) supporting the mission also were required for Shuttle or Atlas V operations at LC 40/41 at Cape Canaveral Air Force Station. At LC 39B, several Shuttle-specific access arms were removed and others were added to accommodate the in-line Ares vehicle. Ground command, control, and communication (GC3) hardware was incorporated into the Mobile Launcher Platform (MLP). The lightning protection system at LC 39B was replaced by a trio of 600-foot-tall towers connected by a catenary wire to account for the much greater height of the vehicle. Like Shuttle, Ares I-X will be stacked on a MLP and rolled out to the pad on a Saturn-era crawler-transporter. While Ares I-X was only held in place by the four hold-down posts on its aft skirt during rollout, a new vehicle stabilization system (VSS) attached to the vertical service structure kept the vehicle from undue swaying prior to launch at the pad, LC 39B. Following the launch, the flight test vehicle first stage was recovered with the aid of new parachutes resized to accommodate the five-segment-long first stage, which had a much greater length and mass than the Shuttle s reusable solid rocket boosters. After splashdown, recovery divers exercised extra care when handling the first stage to ensure that the flight data recorders in the fifth segment simulator were not damaged by exposure to sea water. The data recovered from the Ares I-X flight test will be very valuable in verifying the predicted environments and models used to design the vehicle. Lessons learned from Ares I-X will be shared with the Ares Projects through written and verbal reports and through integration of mission team members into the Project workforce.
Dynamic analysis of peg-in-hole insertion for manufacturing automation

Abstract Dynamic equilibrium and geometric compatibility conditions and constraints to successfully insert a slightly misaligned peg in a hole in assembly processes are discussed. A new, generalized inequality for no-wedging situations is obtained for small orientation of the peg with respect to the axis of the hole. Generalized inequalities for no-jamming in dynamic situations are also provided for the same conditions. An algorithm is also presented to successfully design motion trajectories for no-jamming or no-wedging occurring during assembly processes and during the insertion of a peg in a hole.
Modeling the Democratic Peace as a Kantian Selection Process

Computational modeling is used to improve our understanding of how the democratic peace unfolds as a historical process in time and space. Whereas most of the conventional literature interprets the phenomenon as a constant and universal law operating at the state level, the author follows Immanuel Kant and treats democratic cooperation as an emergent macroprocess. The current study explores three causal mechanisms. First, strategic tagging introduces a way for democracies to select out like-minded cooperators. Second, regime-sensitive alliances enable democratic states to defend the gains of cooperation. Third, liberal collective security complements the liberal alignments. Based on these processes, it is possible to “grow” cooperative outcomes in an inhospitable geopolitical environment. Because tagging alone is insufficient, alliances, and sometimes even collective security, are necessary to produce perpetual peace. Such outcomes are characterized by high levels of spatial clustering.
Single molecule studies of homologous recombination

Single molecule methods offer an unprecedented opportunity to examine complex macromolecular reactions that are obfuscated by ensemble averaging. The application of single molecule techniques to study DNA processing enzymes has revealed new mechanistic details that are unobtainable from bulk biochemical studies. Homologous DNA recombination is a multi-step pathway that is facilitated by numerous enzymes that must precisely and rapidly manipulate diverse DNA substrates to repair potentially lethal breaks in the DNA duplex. In this review, we present an overview of single molecule assays that have been developed to study key aspects of homologous recombination and discuss the unique information gleaned from these experiments.
Machine Learning Tools for Automatic Mapping of Martian Landforms

Automated or semiautomated tools for Martian data analysis can substantially broaden the scope of scientific inquiry. Recognizing this opportunity, we've undertaken research to apply pattern-recognition and machine-learning tools to automatic analysis and characterization of the Mars surface. This research includes machine surveys of specific Iandforms, such as impact craters and valley networks, and automatic generation of geomorphic maps. A geomorphic map is a thematic map of topographical expressions or landforms. Machine learning can play a vital role in automating this mapping process. A learning system can employ clustering techniques to fully automate the discovery of meaningful landform classes. A clustering tool based on unsupervised learning offers maximum automation for geomorphic mapping.
Critical care transport of patients who have acute neurological emergencies.

This article reviews the special questions and issues in critical care transport related specifically to the care of patients who have neurologic emergencies. It first considers potential indications for transport and reviews attempts to create a hierarchical stroke center system akin to that developed for trauma care. It then discusses therapeutic concerns relating to the transport environment and the use of specific interventions, including the effects of end-tidal CO 2 monitoring on intracranial pressure, patient outcomes after traumatic brain injury, and opportunities to initiate therapeutic hypothermia in comatose survivors of cardiac arrest during transport. Finally, the cost of critical care transport of patients who have neurologic emergencies is considered.
High-temperature sensing using surface relief fiber Bragg gratings

We present a new type of fiber Bragg grating (FBG) that can be used in high-temperature sensing applications. We use the flat side of a D-shaped optical fiber as a platform to etch the grating into the surface of the fiber. Because the grating becomes a physical feature of the fiber, it is not erased at high temperatures as are standard FBGs. These surface relief fiber Bragg gratings will operate up to high temperatures. We provide a brief explanation of the fabrication process and present our results for operation up to 1100/spl deg/C.
Implementation a hybrid MAS and SPA algorithm for broadband electromagnetic induction problems

The computational complexity/efficiency of the method of auxiliary sources (MAS) is significantly reduced at high frequency (high induction number >40) for electromagnetic induction problems. At the same time the small penetration-depth approximation (SPA) is very accurate at high frequency/induction numbers. A hybrid algorithm, combining the MAS with SPA, is efficiently implemented. Numerical experiments are performed for a highly conducting and permeable sphere and a prolate spheroid under a time varying primary magnetic field. Numerical experiments demonstrate that the proposed method is able to produce very accurate results with low computational requirements.
Repeated Exposure to Pornography and Arousal Levels of Subjects Varying in Guilt

The present research attempted to determine whether the negative relationship between level of guilt and tendency to respond sexually which is often found in the literature was due to the fact that guilt reduces sexual arousal as suggested by Galbraith (1968). Two studies were performed. In Study 1, 42 male undergraduates rated sexual arousal as well as a variety of other feelings after reading each of eight different pornographic passages. In Study 2, 40 subjects made similar ratings each time after reading the same page of pornography for eight trials. In both studies subjects high and low in sex guilt initially reported a moderate level of sexual arousal which then declined with repeated exposure. The minimal sexual responding of subjects high in guilt found in the literature may very likely be a function of inhibition and not, as Galbraith suggests, a function of a lower level of sexual arousal.
Methylation of FrzCD Defines a Discrete Step in the Developmental Program of Myxococcus xanthus

Myxococcus xanthus is a gram-negative soil bacterium which undergoes fruiting body formation during starvation. The frz signal transduction system has been found to play an important role in this process. FrzCD, a methyl-accepting taxis protein homologue, shows modulated methylation during cellular aggregation, which is thought to be part of an adaptation response to an aggregation signal. In this study, we assayed FrzCD methylation in many known and newly isolated mutants defective in fruiting body formation to determine a possible relationship between the methylation response and fruiting morphology. The results of our analysis indicated that the developmental mutants could be divided into two groups based on their ability to show normal FrzCD methylation during development. Many mutants blocked early in development, i.e., nonaggregating or abnormally aggregating mutants, showed poor FrzCD methylation. The well-characterized asg, bsg, csg, and esg mutants were found to be of this type. The defects in FrzCD methylation of these signaling mutants could be partially rescued by extracellular complementation with wild-type cells or addition of chemicals which restore their fruiting body formation. Mutants blocked in late development, i.e., translucent mounds, showed normal FrzCD methylation. Surprisingly, some mutants blocked in early development also exhibited a normal level of FrzCD methylation. The characterized mutants in this group were found to be defective in social motility. This indicates that FrzCD methylation defines a discrete step in the development of M. xanthus and that social motility mutants are not blocked in these early developmental steps.
Examining the Role of Tube Feeding After Liver Transplantation

The rates of morbidity and mortality after liver transplantation are related to the degree of malnutrition. Because malnutrition is prevalent among liver transplant recipients, nutrition care practitioners must be aggressive in providing nutrition support to these patients in the perioperative period. Postoperative tube feeding (TF) has been studied for its role in improving short-term posttransplant outcomes. This paper evaluates published research that studied postoperative TF in liver transplant recipients; the methodology and outcomes are reviewed and drawbacks of these studies are considered. Case studies of liver transplant patients who received postoperative TF illustrate the variability of patient profiles and posttransplant complications that influence the provision and duration of posttransplant TF.
Electrostatically balanced comb drive for controlled levitation

An experimental study of the levitation force, normal to the substrate, associated with interdigital capacitor electrostatic comb lateral actuators is reported. For compliant suspensions, normal displacements of over 2 mu m for a comb bias of 30 V were observed. This phenomenon is due to electrostatic repulsion by image charges mirrored in the ground plane beneath the suspended structure. By electrically isolating alternating drive-comb fingers and applying voltages of equal magnitude and opposite sign, levitation can be reduced by an order of magnitude while reducing the lateral drive force by less than a factor of two. >
The landscape of human proteins interacting with viruses and other pathogens.

Infectious diseases result in millions of deaths each year. Mechanisms of infection have been studied in detail for many pathogens. However, many questions are relatively unexplored. What are the properties of human proteins that interact with pathogens? Do pathogens interact with certain functional classes of human proteins? Which infection mechanisms and pathways are commonly triggered by multiple pathogens? In this paper, to our knowledge, we provide the first study of the landscape of human proteins interacting with pathogens. We integrate human–pathogen protein–protein interactions (PPIs) for 190 pathogen strains from seven public databases. Nearly all of the 10,477 human-pathogen PPIs are for viral systems (98.3%), with the majority belonging to the human–HIV system (77.9%). We find that both viral and bacterial pathogens tend to interact with hubs (proteins with many interacting partners) and bottlenecks (proteins that are central to many paths in the network) in the human PPI network. We construct separate sets of human proteins interacting with bacterial pathogens, viral pathogens, and those interacting with multiple bacteria and with multiple viruses. Gene Ontology functions enriched in these sets reveal a number of processes, such as cell cycle regulation, nuclear transport, and immune response that participate in interactions with different pathogens. Our results provide the first global view of strategies used by pathogens to subvert human cellular processes and infect human cells. Supplementary data accompanying this paper is available at http://staff.vbi.vt.edu/dyermd/publications/dyer2008a.html.
The Social Dimensions of Entrepreneurship

Schumpeter’s canonical depiction of the entrepreneur as an agent of social and economic change implies that entrepreneurs are especially sensitive to the social environment. We use an organizing framework based on institutional economics, in combination with lessons from cross-cultural psychology, to consider the social dimensions of entrepreneurship. The level and modes of entrepreneurial activity are affected by the surrounding culture and by legal rules. Entrepreneurs may partially overcome institutional deficiencies by relying on social networks that facilitate reputational bonding as a means for resource-sharing.
Synthesis and properties of reactively compatibilized polyester and polyamide blends

The functionalization of poly(butylene terephthalate) (PBT) has been accomplished in a twin screw extruder by grafting maleic anhydride (MA) using a free radical polymerization technique. The resulting PBT-g-MA was successfully used as a compatibilizer for the binary blends of polyester (PBT) and polyamide (PA66). Enhanced mechanical properties were achieved for the blend containing a small amount (as low as 2.5 %) of PBT-g-MA compared to the binary blend of unmodified PBT with PA66. Loss and storage moduli for blends containing compatibilizer were higher than those of uncompatibilized blends or their respective polymers. The grafting and compatibilization reactions were confirmed using FTIR and 13C NMR spectroscopy. The properties of these blends were studied in detail by varying the amount of compatibilizer, and the improved mechanical behaviour was correlated with the morphology with the help of scanning electron microscopy. Morphology studies also revealed the interfacial interaction in the blend containing grafted PBT. The improvement in the properties of these blends can be attributed to the effective interaction of grafted maleic anhydride groups with the amino group in PA66. The results indicate that PBT-g-MA acts as an effective compatibilizer for the immiscible blends of PBT and PA66. © 2000 Society of Chemical Industry
The gas-phase acidity of cyclopropene and simple alkyl derivatives: can they be measured?

Abstract The gas-phase acidity of 3-methylcyclopropene ( 5 ) at the allylic position was explored computationally and experimentally. G2+ calculations indicate that Δ H ° acid = 415.5 kcal/mol making 3-methyl-3-cyclopropenyl anion ( 6 ) an extremely strong base. This species is also predicted to be unstable with respect to electron loss (EA(3-methyl-3-cyclopropenyl radical) = −1.54 kcal/mol). A kinetic approach for determining the acidity of 5 using the hydroxide-induced desilylation of 3-methyl-3-trimethylsilylcyclopropene (the DePuy method) was employed but fails in this case because of an unanticipated rearrangement. This raises the question: Can the acidity of cyclopropene and its simple alkyl derivatives be measured? Positive and negative responses to this question are given and discussed.
Retraining industrial employees for a career in programming

The author describes how one American corporation (International Business Machines Corp.) took a group of its employees from varying and diverse backgrounds and re-educated them to become computer programmers. The generalities of the program are discussed. These include how the program was administered, what was the length of the program, and what were the restrictions of the program. The specific educational plan that each student was expected to undergo is reported. The bulk of the courses were computer science courses and each course is briefly described.
High-order surface relaxation versus the Ehrlich–Schwoebel effect

We consider a class of continuum models of epitaxial growth of thin films with two competing mechanisms: (1) the surface relaxation described by high-order gradients of the surface profile and (2) the Ehrlich–Schwoebel (ES) effect which is the asymmetry in the adatom attachment and detachment to and from atomic steps. Mathematically, these models are gradient-flows of some effective free-energy functionals for which large slopes are preferred for surfaces with low energy.We characterize the large-system asymptotics of the minimum energy and the magnitude of gradients of energy-minimizing surfaces. We also show that, in the large-system limit, the renormalized energy with an infinite ES barrier is the Γ-limit of those with a finite one, indicating the enhancement of the ES effect in a large system. Introducing λ-minimizers as energy minimizers among all candidates that are spatially λ-periodical, we show the existence of a sequence of such λ-minimizers that are in fact equilibriums. For the case of a finite ES effect, we prove the well-posedness of the initial-boundary-value problem of the continuum model and obtain bounds for the scaling laws of interface width, surface slope and energy, all of which characterize the surface coarsening during the film growth. We conclude with a discussion on the implications of our rigorous analysis.
Severe Depletion of CD4+ CD25+ Regulatory T Cells from the Intestinal Lamina Propria but Not Peripheral Blood or Lymph Nodes during Acute Simian Immunodeficiency Virus Infection

CD4+ CD25+ regulatory T cells (Tregs) suppress the activation and proliferation of effector lymphocytes. In human immunodeficiency virus type 1 (HIV-1) infection, Tregs play a significant role in controlling the apoptotic loss of uninfected CD4+ T cells resulting from high levels of generalized immune activation. During acute HIV-1 infection, more than 50% of CD4+ T cells are depleted from the gastrointestinal lamina propria. To elucidate the role of Tregs in HIV-1-induced depletion of CD4+ T cells in the gut-associated lymphoid tissue (GALT), we first determine the distribution of Tregs in a setting of acute infection using the simian immunodeficiency virus (SIV)/pigtailed macaque model of HIV-1 disease. CD4+ T cells from the GALT, lymph nodes, and peripheral blood were isolated from SIV-infected pigtailed macaques on days 4, 14, and 114 postinoculation. Quantitative real-time reverse transcription-PCR was used to quantitate FOXP3 copy numbers in SIV-infected and uninfected control macaques. Expression of FOXP3 in the ileal lamina propria was significantly decreased at all stages of infection compared to levels in uninfected control macaques. In addition, functional analysis of ileal CD4+ T cells from SIV-infected macaques revealed a lack of suppressive activity suggestive of the absence of Tregs in that compartment. These results indicate that Tregs are rapidly depleted in the GALT of SIV-infected macaques, defining a role for the loss of Treg-mediated suppression in early events in the pathogenesis of the disease.
Large Artery Stiffening With Weight Gain in Humans: Role of Visceral Fat Accumulation

We tested the hypothesis that weight gain would increase arterial stiffness in healthy nonobese adults. To address this, we overfed 14 nonobese men (age: 23+/-1 years) approximately 1000 kcal/d for 6 to 8 weeks until a 5-kg weight gain was achieved. Carotid diameters (high-resolution ultrasound) and pressures (applanation tonometry), body composition (dual energy x-ray absorptiometry), and abdominal fat distribution (computed tomography) were measured at baseline and following 4 weeks of weight stability at each individual's elevated body weight. Overfeeding increased body weight 5.1+/-0.1 kg and body fat 3.4+/-0.4 kg (both P<0.001) in 45+/-7 days. Total abdominal fat increased 46+/-7 cm(2) with weight gain due to increases in both subcutaneous (30+/-6 cm(2)) and visceral fat (15+/-4 cm(2); all P<0.01). As hypothesized, weight gain increased arterial stiffness 13+/-6% and decreased arterial compliance 21+/-4% (both P<0.05). Furthermore, those individuals above the median increase in abdominal visceral fat demonstrated a significantly greater increase in arterial stiffness (0.97+/-0.29 versus 0.06+/-0.36 U; P<0.05) compared with those below the median. Consistent with these observations, the only correlates of the changes in arterial stiffness with weight gain were the increases in total abdominal fat (r=0.794), abdominal visceral fat (r=0.651), and waist circumference (r=0.470; all P<0.05). Taken together, these findings suggest that modest weight gain is associated with increases arterial stiffness in nonobese men. The degree of large artery stiffening with weight gain seems to be determined, in part, by the amount of abdominal visceral fat gain. Importantly, this relation is independent of the amount of total body fat gained.
Monogamy on the fast track.

Social monogamy has evolved multiple times and is particularly common in birds. It is not well understood why some of these species are continuously and permanently paired while others occasionally ‘divorce’ (switch partners). Although several hypotheses have been considered, experimental tests are uncommon. Estrildid finches are thought to be permanently paired because being short-lived opportunistic breeders, they cannot afford the time to form a new pair relationship. Here it is shown through a controlled experimental manipulation that zebra finches (Taeniopygia guttata) allowed to remain with their partners to breed again are faster to initiate a clutch (by approx. 3 days) than birds separated from their mates that have to re-pair, supporting the hypothesis that continuous pairing speeds up initiation of reproduction, a benefit of long-term monogamy in a small, short-lived, gregarious species.