cssi/SciSciGPT-SciSciNet huggingface dataset:
TU-AB-BRD-00: Task Group 100

Current quality assurance and quality management guidelines provided by various professional organizations are prescriptive in nature, focusing principally on performance characteristics of planning and delivery devices. However, published analyses of events in radiation therapy show that most events are often caused by flaws in clinical processes rather than by device failures. This suggests the need for the development of a quality management program that is based on integrated approaches to process and equipment quality assurance. Industrial engineers have developed various risk assessment tools that are used to identify and eliminate potential failures from a system or a process before a failure impacts a customer. These tools include, but are not limited to, process mapping, failure modes and effects analysis, fault tree analysis. Task Group 100 of the American Association of Physicists in Medicine has developed these tools and used them to formulate an example risk-based quality management program for intensity-modulated radiotherapy. This is a prospective risk assessment approach that analyzes potential error pathways inherent in a clinical process and then ranks them according to relative risk, typically before implementation, followed by the design of a new process or modification of the existing process. Appropriate controls are then put in place to ensure that failures are less likely to occur and, if they do, they will more likely be detected before they propagate through the process, compromising treatment outcome and causing harm to the patient. Such a prospective approach forms the basis of the work of Task Group 100 that has recently been approved by the AAPM. This session will be devoted to a discussion of these tools and practical examples of how these tools can be used in a given radiotherapy clinic to develop a risk based quality management program. Learning Objectives: 1. Learn how to design a process map for a radiotherapy process 2. Learn how to perform failure modes and effects analysis analysis for a given process 3. Learn what fault trees are all about 4. Learn how to design a quality management program based upon the information obtained from process mapping, failure modes and effects analysis and fault tree analysis. Dunscombe: Director, TreatSafely, LLC and Center for the Assessment of Radiological Sciences; Consultant to IAEA and Varian Thomadsen: President, Center for the Assessment of Radiological Sciences Palta: Vice President of the Center for the Assessment of Radiological Sciences
Convergence, Targeted Optimality and Safety in Multiagent Learning

In the previous chapter, we presented an algorithm LoE-AIM that models memory-bounded agents assuming that the memory size of these agents is known beforehand. In situations where such prior knowledge is unavailable, a possible solution can be to use a very large memory size that suffices to be a conservative upper-bound of the true unknown memory size.
Insider Trading Law (US)

Federal regulation of insider trading occurs through three main sources: Section 16 of the Securities Exchange Act of 1934, Securities and Exchange Commission (SEC) Rule 10b-5, and SEC Rule 14e-3. Keywords: insider trading law
Sulfation of chondroitin. Specificity, degree of sulfation, and detergent effects with 4-sulfating and 6-sulfating microsomal systems

Microsomal preparations from chondroitin 6-sulfate-producing chick embryo epiphyseal cartilage, and from chondroitin 4-sulfate-producing mouse mastocytoma cells, were incubated with UDP-[14C]glucuronic acid and UDP-N-acetylgalactosamine to form non-sulfated proteo[14C]chondroitin. Aliquots of the incubations were then incubated with 3'-phosphoadenylylphosphosulfate (PAPS) in the presence or absence of various detergents. In the absence of detergents, there was good sulfation of this endogenous proteo[14C]chondroitin by the original microsomes from both sources. Detergents, with the exception of Triton X-100, markedly inhibited sulfation in the mast cell system but not in the chick cartilage system. These results indicate that sulfation and polymerization are closely linked on cell membranes and that in some cases this organization can be disrupted by detergents. When aliquots of the original incubation were heat inactivated, and then reincubated with new microsomes from chick cartilage and/or mouse mastocytoma cells plus PAPS, there was no significant sulfation of this exogenous proteo[14C] chondroitin with either system unless Triton X-100 was added. Sulfation of exogenous chondroitin and chondroitin hexasaccharide was compared with sulfation of endogenous and exogenous proteo[14C]chondroitin. Sulfate incorporation into hexasaccharide and chondroitin decreased as their concentrations (based on uronic acid) approached that of the proteo[14C]chondroitin. At the same time, the degree of sulfation in percent of substituted hexosamine increased. However, the degree of sulfation did not reach that of the endogenous proteo[14C]chondroitin. Hexasaccharide and chondroitin sulfation were stimulated by the presence of Triton X-100. However, in contrast to the exogenous proteo[14C]chondroitin, there was some sulfation of hexasaccharide and chondroitin in the absence of this detergent. These results indicate that the intact microsomal system was not accessible to the larger substrates, and that even with detergents exogenous substrates were not sulfated as effectively as newly formed proteo[14C]chondroitin in an intact microsomal system. When the proteo[14C]chondroitin formed by the chick cartilage microsomal system was incubated together with the mast cell microsomal system and PAPS, sulfation only occurred at the 4-position. When the proteo[14C]chondroitin formed by the mouse mast cell microsomal system was incubated together with the chick cartilage microsomal system and PAPS, sulfation only occurred at the 6-position.(ABSTRACT TRUNCATED AT 400 WORDS)
Dirac magnetic-monopole pair production in relativistic nucleus-nucleus collisions

Dirac magnetic-monopole pair production is examined for very-high-energy nucleus-nucleus collisions. Comparisons are made, for various masses of the magnetic monopole, between the rate at which pairs are produced via the Drell-Yan mechanism and from thermalized quark-gluon matter. To do this the fireball model is used. It is pointed out that properties of the quark-gluon plasma can be determined by an accurate specification of the monopole mass. Specifically, lower limits on the energy density of the quark-gluon plasma as well as its temperature can be determined in this way in the kinematical regions where experiment will be able to verify the thermal production of magnetic-monopole pairs. It is pointed out that very-high-multiplicity gamma-ray events are a possible signature of monopole-antimonopole annihilation and a Monte Carlo simulation of this process is performed for various masses of the decaying pair to give the expected multigamma distributions, should this process occur, for a proposed 4π detector.
The Effects of Tip Leakage Flow on the Performance of Multistage Compressors Used in Small Core Engine Applications

Large rotor tip clearances and the associated tip leakage flows are known to have a significant effect on overall compressor performance. However, detailed experimental data reflecting these effects for a multistage compressor are limited in the open literature. As design trends lead to increased overall compressor pressure ratio for thermal efficiency benefits and increased bypass ratios for propulsive benefits, the rear stages of the high-pressure compressor will become physically small. Because rotor tip clearances cannot scale exactly with blade size due to the margin needed for thermal growth considerations, relatively large tip clearances will be a reality for these rear stages. Experimental data have been collected from a three-stage axial compressor to assess performance with three-tip clearance heights representative of current and future small core machines. Trends of overall pressure rise, stall margin, and efficiency are evaluated using clearance derivatives, and the summarized data presented here begin to narrow the margin of tip clearance sensitivities outlined by previous studies in an effort to inform future compressor designs. Furthermore, interstage measurements show stage matching changes and highlight specific differences in the performance of rotor 1 and stator 2 compared to other blade rows in the machine.
Online residence time distribution measurement of thermochemical biomass pretreatment reactors

Residence time is a critical parameter that strongly affects the product profile and overall yield achieved from thermochemical pretreatment of lignocellulosic biomass during production of liquid transportation fuels. The residence time distribution (RTD) is one important measure of reactor performance and provides a metric to use when evaluating changes in reactor design and operating parameters. An inexpensive and rapid RTD measurement technique was developed to measure the residence time characteristics in biomass pretreatment reactors and similar equipment processing wet-granular slurries. Sodium chloride was pulsed into the feed entering a 600 kg/d pilot-scale reactor operated at various conditions, and aqueous salt concentration was measured in the discharge using specially fabricated electrical conductivity instrumentation. This online conductivity method was superior in both measurement accuracy and resource requirements compared to offline analysis. Experimentally measured mean residence time values were longer than estimated by simple calculation and screw speed and throughput rate were investigated as contributing factors. In conclusion, a semi-empirical model was developed to predict the mean residence time as a function of operating parameters and enabled improved agreement.
Parametric Variations of Palladio's Villa Rotonda

A computational tool for the study of proportional balance is introduced as an apparatus for investigating Andrea Palladio's design of Villa Almerico, more familiarly known as Villa Rotonda, in the second book of his Quattro Libri dell'Architettura. The objective of this investigation of Villa Rotonda is to find a novel outcome from the morphological transformations of the villa, where the transformations are generated from parametric variations of the villa while maximizing its proportional balance. The outcome confirms Palladio's mastery of proportional treatments of his design of Villa Rotonda and shows various morphological descendants evolved from the original design. It suggests a new way of employing a parametric geometry in the formal study of a classical building and its stylistic evolution.
Heat Denaturation of β-Lactoglobulins A and B

Summary β -Lactoglobulin B was more rapidly denatured than β -lactoglobulin A by heat treatments of skimmilk or solutions of the isolated proteins at pH 6.7 in the temperature range of 67 to 75C. Three criteria of denaturation, solubility at pH 5.0, sulfhydryl group activity, and specific optical rotation, all demonstrated the difference in denaturability of the two proteins. They were found to differ in energy of activation and in entropy of activation. Both proteins undergo both the primary and secondary stages in heat denaturation.
Isolation, characterization, and structure of the folded interphase genome of Drosophila melanogaster

The intact interphase genome of Drosophila melanogaster has been isolated by sucrose gradient centrifugation after gentle lysis of tissue culture cells in 0.9 M NaCl-0.4% nonidet P40. The non-viscous folded DNA sediments as a single broad 5000S peak in a complex with RNA (a fraction of the nuclear nascent RNA) and protein (all of the four intranuclesome histones: H2A, H2B, H3, and H4). The folded DNA is supercoiled and can be relaxed to slower sedimenting forms either by intercalating ethidium or by nicking with DNAase I. Incomplete DNAase treatment gives partially relaxed complexes, indicating that each nick relaxes only a stretch of DNA (defined as a supercoiled DNA loop) without affecting the superhelical content of the rest of the genome. The concentration of superhelices in the Drosophila folded DNA is the same as in the E. coli and SV40 closed circular DNAs-that is, about one negative turn every 200 base pairs (bp) in 0.15 M NaCl at 26 degrees C. The estimated average size of the supercoiled DNA loops, about 85,000 bp, equals the size of the larger Drosophila chromomeres. Ethidium intercalation in 0.9 M NaCl both removes the negative superhelical turns and dissociates the four histones from the DNA. The four histones are dissociated in equimolar concentrations, and the relative proportion of histones displaced from the DNA is a function of ethidium concentration. The histones are completely dissociated from the folded DNA at the ethidium concentration. The histones are completely dissociated from the folded DNA at the ethidium concentration which removes all of the negative superhelices. Thus the data strongly suggest that the rotation of the Watson Crick helix which accompanies ethidium intercalation causes the loss of nucleosomes from the DNA. The results are interpreted in terms of a model for the folded Drosophila genome which has the DNA constrained (by both protein-DNA and RNA- DNA interactions) into independent supercoiled loops containing on the average 400 nucleosomes per loop. Each nucleosome is composed of a histone core with the DNA wound around it in a 360 degrees left-handed toroidal supercoil; each nucleosome toroidal supercoil plus its relaxed internucleosome DNA contains, on the average, 200 bp.
Dynamics of vortex rings in viscous fluids

As part of a long range study of vortex rings, their dynamics, interactions with boundaries and with each other, we present the results of experiments on thin core rings generated by a piston gun in water. We characterize the dynamics of these rings by means of the traditional equations for such rings in an inviscid fluid suitably modifying them to be applicable to a viscous fluid. We develop expressions for the radius, core size, circulation, and bubble dimensions of these rings.
Orbital motion, nucleus precession, and splitting of periodic Comet Brooks 2

Results of ten nongravitational orbital solutions are given for Comet Brooks 2, based on observations from the apparitions 1889-1980. The time history of the nongravitational parameters, including the transverse component A-sub-2, is vital for modeling the nucleus precession. The comet is obviously a fragment of a once larger object that split during a close encounter with Jupiter in 1886. Factors possibly responsible for the breakup are examined. A similarity between the orbital histories of P/Brooks 2 and P/Wild 2 is noted.
Complex coordinate calculations of resonances in N‐electron atoms

A discussion is presented of the functional dependences of the wave functions for bound, resonant, and scattering states on the radial coordinate rho and the rotation angle ..cap alpha.. in the complex coordinate method. It is concluded that for bound states and resonances, rho and ..cap alpha.. are constrained to appear in the wave functions only in the form rho exp (i..cap alpha..). On the other hand, this constraint is not obtained for the scattering states since the energy of the scattering states depends on ..cap alpha... In addition a partitioning of the resonant wave function into two parts--a boundlike or Q-space part and a scattering like or P-space part is suggested. With these concepts one can incorporate physical insight into the choice of configurations as one does in other methods and can apply the complex coordinate method to many electron systems with an expected rate of convergence similar to other techniques. Its advantages are that a single calculation yields the position and width of the resonance, only square integrable functions are used, only a solution of a straightforward eigenvalue problem is required unlike some methods, arbitrarily accurate target states are easily incorporated, and polarization terms can easily be explicitlymore » included. Variational calculations for the position and width of the lowest /sup 2/S resonance in the negative helium ion are reported using trial wave functions containing 39, 43, 55, 24, and 32 P-space configurations, respectively. Values of 19.387 eV and 12.13 MeV are obtained for the position and width, respectively, for the resonance over a range in the rotation angle of almost two orders of magnitude. One also finds that inclusion of free-particle-like basis functions improves the representation of the scattering states. 21 references.« less
Accumulation of nitrite in denitrifying barriers when phosphate is limiting

Permeable in situ denitrifying barriers can remove nitrate from groundwater. Barriers may be constructed by filling an excavated area with a porous mixture of sand, fine gravel, and substrate or by the injection ofa nonaqueous phase substrate into anaquifer. The substrate stimulates the development of a denitrifying microbial community by providing an electron donor. The objective of this study was to determine the ability of denitrifying barriers to function under low-phosphate conditions. Sand columns injected with a soybean oil emulsion were used as laboratory models of denitrifying barriers. When a natural groundwater containing 17 mg l 1 nitrate-N and 0.009 mg l 1 phosphate-P was pumped through the columns, only a small amount of nitrate was removed from the water and, in some effluent fractions, 52% to 88% of the influent nitrate had converted to nitrite. Nitrite also accumulated when the phosphate concentration of the groundwater was increased to 0.040 or 0.080 mg l 1 phosphate-P. Only when a 0.160 mg l 1 phosphate-P supplement was added to the groundwater was there a loss of nitrate without a large accumulation of nitrite. The addition of solid calcium phosphate or rock phosphate to the sand columns was found to provide adequate phosphate for denitrification in short-term studies. These studies point out the need to ensure that adequate phosphate is present in denitrifying barriers especially when such barriers are used beneath phosphate-binding soils. Published by Elsevier Science B.V.
LIQUID-LIQUID PHASE TRANSFORMATION IN CARBON

A first order phase transition is found in liquid carbon using atomistic simulation methods and Brenner{close_quote}s bond order potential. The phase line is terminated by a critical point at 8801thinspthinspK and 10.56thinspthinspGPa and by a triple point on the graphite melting line at 5133thinspthinspK and 1.88thinspthinspGPa. The phase change is associated with density and structural changes. The low-density liquid is predominantly sp bonded with little sp{sup 3} character. The high-density liquid is mostly sp{sup 3} bonded with little sp character. This is the first nonempirical evidence of a liquid-liquid transition between thermodynamically stable fluids. {copyright} {ital 1999} {ital The American Physical Society}
ON THE DURATION OF THE ISOVOLUMETRIC RELAXATION PERIOD (IVRP) IN DOG AND MAN.

Abstract The isovolumetric relaxation period (IVRP) was studied in 13 normal, anesthetized dogs and in 30 human subjects without hemodynamically significant abnormalities. In dogs, this period was measured for the left heart from the aortic component of the second sound to the crossing of left atrial and ventricular pressure curves. A correlation between this period and the heart rate was made. In human subjects, this period was measured on catheterization of the right side of the heart in 14 cases, on catheterization of the left side of the heart in 5 cases, and on catheterization of both the right and left sides in 9 cases. Measurements were made from the incisura of the pulmonary artery or aorta, respectively, and crossing of atrial and ventricular pressures of the respective side. In dogs, the IVRP increased when passing from severe tachycardia to normal rate. On the contrary, a trend toward decrease was noted in bradycardia. The averages varied from 37 to 74.3 msec. In human subjects the IVRP of the left heart was longer than that of the right heart in 7 cases, and shorter in 2 cases. No difference was found in the various age groups, and no correlation with heart rate, possibly because the rates varied within a limited range. In human subjects the average duration of the IVRP of the left heart was 81.6 msec., with a maximum of 120 and a minimum of 55. For the right heart, the average was 49.2, the maximum, 11.5, and the minimum, 35. Even though the IVRP of the right heart is shorter than that of the left, pulmonary incisura follows aortic incisura. Thus, the openings of the tricuspid and mitral valves may be simultaneous.
Generalizing witnesses to the non-normality of Nω1

Abstract We generalize A.H. Stoneʼs witnesses to the non-normality of N ω 1 and produce new strong witnesses to the non-normality with a pair of disjoint countable closed discrete sets that fail to have an open separation by open sets having disjoint closures. Our generalization of A.H. Stoneʼs witnesses yields among other things that all closed subsets of N ω 1 with non-Lindelof boundaries fail to have an open separation with a closed disjoint homeomorphic copy of themselves.
Biostratigraphic correlation within IGCP Project 148

Abstract Although embryonic, quantitative biostratigraphy is alive and hopefully well. The potential for future growth clearly is present and will be fostered by IGCP Project 148 which is charged with the development of algorithms as well as the evaluation of methods through rigorous case studies. Sequencing methods produce a dimensionless list of events. Such a list is effective for correlation but yields little information about environments or discontinuities between different faunal zones. Quantified assemblage zones provide information about environments and stratigraphy although the resulting correlations usually are less precise. Assemblage zones also point out the locations of faunal discontinuities. The information contained in an evolutionary sequence consists of a continuous or discontinuous spectrum of morphological or taxonomic changes in time and space, depending on the method of analysis and the evolutionary lineage or lineages under study.
Reachability, persistence, and constructive chemical reaction networks (part II): a formalism for species composition in chemical reaction network theory and application to persistence

Chemical Reaction Network Theory uses mathematics to study systems of reactions and infer their properties from their structure. At the onset is an abstract definition of a chemical reaction network which is very general and is pertinent beyond chemistry, e.g. in modeling interactions of microscopic and macroscopic living species. This allows the theory to provide widely applicable theorems. It also results in that the idea of chemical composition is mostly used implicitly in examples to illustrate theorems, not explicitly to establish new properties. In this paper we propose a formalism for species composition in a way that generalizes the idea of atomic composition—for instance, elementary species will extend the idea of atoms. We envision that this formalism could lead to more theorems on classes of networks that are of interest in biochemistry. Toward that prospect, we prove that if there is no isomerism among elementary species, and if a newly formalized and widely applicable reversibility condition holds, then a reaction network is vacuously persistent: no species will tend to extinction if all species are implicitly present at initial time. This paper is the second in a series of three articles. The first paper studies vacuous persistence and the third one probes a class of enzymatic networks.
An approach to community consultation prior to initiating an emergency research study incorporating a waiver of informed consent.

Objectives In November 1996, the Food and Drug Administration (FDA) and the Department of Health and Human Services (DHHS) enacted rules allowing a narrow exception to the requirement for prospective informed consent when enrolling critically ill patients in clinical research studies of emergency treatments. These rules require that, prior to initiation of the study, the applicable institutional review board (IRB) assess the acceptability of the proposed research study to members of the community in which the research will be conducted. Specifically, the IRB must perform community consultation-a process during which community members learn about the proposed research and communicate their opinions regarding its acceptability to investigators or IRB representatives. The FDA and DHHS rules do not define specific acceptable methods for performing this community consultation. The objective of this study is to demonstrate the feasibility and utility of one proposed method for performing such community consultation. Methods Parents of children being seen for minor traumatic injuries in three pediatric EDs were asked to participate in a study regarding informed consent. After consent, an instructor described to the parent a prospective, randomized, placebo-controlled trial of phenytoin for the prophylaxis of posttraumatic seizures in children with severe closed head trauma. All parents were then asked whether they would have consented for their own child's participation, if their child had suffered such head injury. The parents were further asked to explain the reason(s) for their responses. Results Parents of 227 children (children's mean +/- SD age 8.0 +/- 4.8 years, 57% male) were interviewed. Sixty-six percent of parents (149/227) stated they would give consent for their child's participation. Of the 149 consenting parents, 85% (126/149) cited potential benefit to their child, 72% (107/149) cited potential benefit to other children, and 60% (90/149) cited furthering medical knowledge. Of the 78 nonconsenting parents (34% of total), 54% (42/78) cited fear of adverse effects, 39% (30/78) did not want their child to be a research subject in general, 27% (21/78) believed they needed to discuss participation with family members who were unavailable, and 26% (20/78) stated they were unable to decide unless they were in the actual situation. Parental ethnicity and household income were found to influence the consent decision, while the parent's gender, religion, language, and educational level were not associated with the consent decision. Conclusions Community consultation regarding the acceptability of an emergency research protocol can be obtained via interview techniques in the ED. This methodology may allow investigators to obtain data on opinion from a targeted community for IRB consideration during the review of emergency research studies proposing a waiver of informed consent.
Magnetic form factor of6Li

By using the shell model for the nucleons and considering an harmonic-oscillator potential with hard core, we have calculated the magnetic form factor of6Li by taking only the contribution of the exterior nucleons to4He core into consideration. We use the linear combination of the radial wave functions, one is regular and the other is irregular atr=0. We obtain the magnetic form factor6Li in good agreement with the experimental values.
Histoplasmosis: Treatment of Two Cases with Beta-diethylaminoethyl Fencholate

The antifungal agent, Beta-diethylaminoethyl fencholate has been demonstrated to inhibit the cultural growth of various fungi including Histoplasma capsulatum. Animals of several species have been subjected to acute and chronic toxicity studies with results that implied adequate safety to warrant clinical trial.1 The purpose of this report is to relate our recent experience with Betadiethylaminoethyl fencholate in the treatment of two patients suffering from histoplasmosis. From Dr. Mackinnon Ellis, we first learned of this new drug, which he was employing in a case of histoplasmosis.2 There has also been a report of its clinical trial by Michael and Vogel3 who started the drug in their case several days after the development of clinical and radiographic improvement. They were unable to assess its usefulness. Because of the relative paucity of cases of active histoplasmosis coming under the observation of any investigator and because the natural course of the disease is unknown, the evaluation of the usefulness of any drug in the treatment of histoplasmosis is difficult. Nevertheless, it is hoped that this report will contribute to an appraisal of the suitability of Betadiethylaminoethyl fencholate in the treatment of histoplasmosis, and will stimulate further study by those who may encounter this uncommon disease. Chronic Pulmonary Histoplasmosis
A novel role for nuclear factor of activated T cells in receptor tyrosine kinase and G protein-coupled receptor agonist-induced vascular smooth muscle cell motility

In addition to their role in cytokine gene regulation in T cells, nuclear factors of activated T cells (NFATs) have been shown to be involved in cardiac development and hypertrophy. We have reported previously that NFATs play an important role in the regulation of vascular smooth muscle cell (VSMC) proliferation by receptor tyrosine kinase (RTK) and G protein-coupled receptor (GPCR) agonists, platelet-derived growth factor-BB (PDGF-BB) and thrombin, respectively. To understand the role of NFATs in vascular disease and development, we have now studied the role of these transcriptional factors in VSMC motility. PDGF-BB and thrombin induced VSMC motility in a dose-dependent manner. Blockade of NFAT activation resulted in substantial reduction in PDGF-BB- and thrombin-induced VSMC motility. PDGF-BB and thrombin also induced interleukin-6 (IL-6) expression in NFAT-dependent manner. Furthermore, IL-6 dose-dependently caused VSMC motility. A neutralizing anti-rat IL-6 antibody inhibited VSMC motility induced by IL-6, PDGF-BB, and thrombin. In addition, exogenous addition of IL-6 rescued both PDGF-BB- and thrombin-induced VSMC motility from inhibition by the blockade of NFAT activation. Together, these results for the first time demonstrate that NFATs mediate both RTK and GPCR agonist-induced VSMC motility via induction of expression of IL-6.
Phenolic Antioxidants of Soy Protein Hydrolyzates

Soy protein hydrolyzate (SPH) was investigated to identify the phenolic compounds responsible for antioxidant activity. Three isoflavones–genistein, daidzein, and glycitein–were found in SPH. These are the same isoflavones that have been identified in raw soybeans. No isoflavone glycosides were found in SPH. The phenolic acids found in SPH were caffeic, ferulic, p-coumaric, syringic, vanillic, gentisic, and p-hydroxybenzoic acids. The compounds were identified by TLC, GLC and UV spectra. The isoflavones were confirmed by their mass spectra.
Optical Double-Photon Absorption in CdS

Observations have been made of the two-photon excitation of an electron from the valence to the conduction band in CdS (${E}_{g}=2.5$ eV) using a pulsed ruby laser ($\ensuremath{\hbar}\ensuremath{\omega}=1.78$ eV). The radiative recombination emission from exciton and impurity levels subsequent to the simultaneous absorption of two quanta of $\ensuremath{\hbar}\ensuremath{\omega}=1.78$ eV was observed as a function of laser intensity and compared to the emission excited by single-quanta absorption for photons of $\ensuremath{\hbar}\ensuremath{\omega}g{E}_{g}$. It was found that the intensity of the recombination radiation is proportional to ${{I}_{0}}^{n}$ for single-quanta excitation and ${{I}_{0}}^{2n}$ for double-quanta excitation, where ${I}_{0}$ is the excitation intensity and $n$ is a constant which differs for different groups of emission lines. The observed cross section for double-quanta excitation is compared with theory utilizing the band parameters of CdS.
Even-Parity States of the Five-Nucleon System and Deuteron-Triton Photocapture

The non-normal-parity states for the five-nucleon system are obtained in the shell-model with particle-hole interactions. The residual force used is the separable smooth potential due to Tabakin. Coupling of the shell-model wave functions to deuteron and single-particle channels is calculated semiquantitatively, and the results are used in an $R$-matrix calculation of the cross section for photocapture of deuterons by tritons. A broad peak in the cross section at about 21-MeV excited energy due to capture through a ${\frac{5}{2}}^{+}$ state is predicted.
TCT-416 Renal Denervation for the Management of Resistant Hypertension: A Meta-Analysis

Renal denervation interrupts the sympathetic pathways to the kidneys and therefore may decrease blood pressure. This technique is increasingly being evaluated for the management of resistant hypertension. All the available electronic databases were queried for studies on renal denervation for
Reduced self-referential source memory performance is associated with interpersonal dysfunction in borderline personality disorder

Source memory is impaired in schizophrenia, and this deficit is related to symptoms of interpersonal antagonism such as suspiciousness and hostility. The present study evaluated source memory in borderline personality disorder (BPD) and its relation to interpersonal antagonism. Forty-one noninpatient adults with BPD according to the DSM-IV and 26 healthy control subjects performed a verbal source memory test requiring completion of sentences with and without emotional content (“Hot” vs. “Cold” sentences). Subjects also completed self-report measures of suspiciousness and interpersonal antagonism (Buss-Durkee Hostility Inventory) and depression (Beck Depression Inventory). The BPD group showed no significant difference from the control group in self-referential source memory, recognition memory, response bias, and performance enhancement for items with emotion content. However, in the BPD group, poorer self-referential source memory was significantly related to Hostility measures including suspiciousness, but not with Depression scores. In contrast, generic item recognition memory was unrelated to Hostility. Heterogeneity in source memory function may be specifically related to some of the hallmark interpersonal disturbances of BPD, independent of the effects of general negative affect or general memory impairment.
Immunomodulation by Bronchial Lavage Cells in Normal Individuals and Patients with Bronchogenic Carcinoma

ABSTRACT The ability of bronchoalveolar lavage cells to facilitate lymphoproliferation to mitogen in a system which allows assessment of pulmonary alveolar macrophage accessory cell function was investigated. Bronchoalveolar lavage cells were obtained from healthy nonsmokers and smokers and from patients undergoing diagnostic bronchoscopy. Lavaged cells were cultured with monocyte-depleted homologous blood lymphocytes obtained from healthy, young volunteers and stimulated with suboptimal (2 μg/ml) or optimal (20 μg/ml) concentrations of phytohemagglutinin. Mitogen responses of lymphocytes in all groups were related to the number of lavage cells added, increasing with 1:100 and 1:10 bronchoalveolar lavage cell to lymphocyte ratios and decreasing with 1:2 and 1:1 ratios. Lymphoproliferative responses observed in smoker and nonsmoker cultures were not different. In contrast, maximal proliferative responses of cell cultures from patients with epidermoid and small cell carcinoma were decreased compared with cultures from patients with adenocarcinoma or controls. These data show that pulmonary bronchial lavage cells from smokers and nonsmokers provide similar dose related augmentation and suppression of lymphocyte mitogenic responses. Furthermore, accessory cell function of lavage cell populations is normal in patients with adenocarcinoma, but depressed in patients with epidermoid or small cell carcinoma.
Fluorinated Polymer Films from Acylation of ATRP Surface-Initiated Poly(hydroxyethyl methacrylate)

We report a new strategy to prepare partially fluorinated polymer films by utilizing surface-initiated films of poly(2-hydroxyethyl methacrylate) (PHEMA) grown onto gold surfaces via atom transfer radical polymerization (ATRP). Hydroxyl side chains of PHEMA were reacted with perfluoroalkyl (C3F7 and C7F15) and perfluoroaryl (C6F5) acid chlorides to yield partially fluorinated surface-initiated polymer films with conversions ranging from ∼70 to 85%. The resulting fluorinated PHEMA films dramatically altered surface and barrier properties, particularly lowering the critical surface tension to as low as 9 mN/m and boosting film resistance by as much as 5 orders of magnitude compared to that of PHEMA. Film properties depend on the chemical composition and length of the fluorinated side chains. The longer C7F15 fluoroalkyl chain structured the film to a greater extent than the shorter C3F7 chain and yielded improved barrier properties and lower critical surface tension. The C7F15 groups are oriented nearly nor...
Extending the Dynamics of Reason

What I call the dynamics of reason is a post-Kuhnian approach to the history and philosophy of science articulating a relativized and historicized version of the Kantian conception of the rationality and objectivity of the modern physical sciences. I here discuss two extensions of this approach. I argue that, although the relativized standards of rationality in question change over time, the particular way in which they do this still preserves the trans-historical rationality of the entire process. I also make a beginning in extending my historical narrative from purely intellectual history (both philosophical and scientific) to the wider cultural context.
Kinetics of cellular permeability of phenoxazine and its dependence on P-glycoprotein expression

Abstract We present here the initial characterization of the mechanism of reversal of cellular resistance to Vinca alkaloids by phenoxazine (PZ). Changes in fluorescence upon cellular accumulation of PZ allowed measurement of the membrane transport kinetics in a sensitive KB-3-1 cell line and two multi-drug resistant (MDR) counterparts. The accumulation of PZ is characterized by two uptake routes, with pseudo-first order rate constants of 0.3 s−1 and 0.07 s−1, while efflux of PZ from cells revealed rate constants of 0.2 s−1. PZ rapidly reaches steady-state concentrations within cells, which may make it more clinically useful than modulators that accumulate more slowly (e.g. verapamil).
Angular resonances in the light emission from atoms near a grating

Abstract A two step light emission process becomes possible when atoms are placed near a metallic grating. The atoms can excite surface plasmons in the grating. The surface plasmons can then emit light. This light is emitted at certain angles determined by momentum conservation in the plane of the grating. Thus, the angles depend on the spacing of the grating. Our measurements on light from nitrogen atoms at distances, d, ranging from 10 to 100 nm from a silver grating are in agreement with a recent theory of Aravind, Hood and Metiu. We also report the effect of a nonsinusoidal grating profile and the emission of light at angles which can be predicted from a straightforward extension of the theory.
Ab initio simulation of defects in energetic materials. Part I. Molecular vacancy structure in RDX crystal

Abstract An attempt to simulate a point defect in energetic molecular solids and to find out its effect on the crystal electronic properties at the ab initio Hartree–Fock level using two different solid-state models was performed. As an example, we have considered a molecular vacancy in RDX crystal, in the periodic and in the molecular cluster model. Low formation energy characterizes this defect in the solid RDX indicating that a significant number of vacancies should be present in the crystal even at low temperatures. Narrowing of fundamental gap (about 1 eV) is caused by the presence of vacancies in the material. The obtained results demonstrate anisotropy of the RDX crystal with respect to the vacancy distribution. Trends received in periodic and molecular cluster models agree well.
Reaction of 5-40 eV ions with self-assembled monolayers.

The reaction of 5-40 eV O + and Ne + ions with alkanethiolate and semifluorinated alkanethiolate self-assembled monolayers (SAMs) is studied under ultrahigh vacuum (UHV) conditions. Whereas Ne + simply sputters fragments from the surface, O + can also abstract surface atoms and break C-C bonds in both the hydrocarbon and fluorocarbon SAM chains. Isotopic labeling experiments reveal that O + initially abstracts hydrogen atoms from the outermost two carbon atoms on an alkanethiolate SAM chain. However, the position of the isotopic label quickly becomes scrambled along the chain as the SAM is damaged through continuous ion bombardment. Scanning tunneling microscopy (STM) monitors changes in the SAM conformational structure at various stages during 5 eV ion bombardment. STM images indicate that O + reacts less efficiently with dodecanethiolate molecules packed internally within a structural domain than it does with molecules adsorbed at domain boundaries or near defect sites. STM images recorded after Ne + bombardment suggest that Ne + attacks the SAM exclusively near the domain boundaries. Taken collectively, these experiments advance our understanding of the degradation pathways suffered by polymeric satellite materials in the low-earth orbit (LEO) space environment.
An Experimental Study on the Coupling of Combustion Instability Mechanisms in a Lean Premixed Gas Turbine Combustor

An experimental study was conducted to characterize the combined effects of flame-vortex interactions and equivalence ratio fluctuations on self-excited combustion instabilities in a swirl-stabilized lean premixed gas turbine combustor. The combustor was designed so that the fuel injector location and the combustion chamber length could be independently varied. In addition, the fuel and air could be mixed upstream of the choked inlet to the combustor, thereby eliminating the possibility of equivalence ratio fluctuations. Experiments were performed over a broad range of operating conditions and at each condition both the combustor length and the fuel injection location were varied. Dynamic pressure in the combustor, acoustic pressure and velocity in the mixing section, and the overall rate of heat release were simultaneously measured at all operating conditions. Two distinct instability regimes were observed; one near 220 Hz and the other near 345 Hz. It was also found that the strength of the instability changed significantly as the fuel injection location was varied, while the phase of the acoustic pressure and velocity fluctuations in the mixing section did not change. A time series of pressure and CH* chemiluminescence signals confirmed constructive or destructive coupling of the two instability mechanisms; the flame-vortex interaction and the equivalence ratio fluctuation interact each other and determine the instability characteristics in partially premixed conditions.Copyright © 2009 by ASME
Optimizing design of two-stage experiments for transcriptional profiling

Gene expression microarrays are powerful tools for simultaneously screening the transcriptional profile for thousands of genes across different treatments. Despite their continually improving sensitivity and dynamic range, microarrays are commonly regarded as a first screening step, with a level of precision often deemed unacceptable to use as a standalone technology. This limitation has prompted genomics researchers to validate a statistically significant subset of their microarray results using a second technique, typically quantitative reverse transcription polymerase chain reaction (qRT-PCR). The problem of optimizing such two-stage transcriptional profiling experiments in order to maximize sensitivity, while controlling the false discovery rate (FDR), is addressed. This optimization is based on partitioning the set of available biological replicates into two groups, one for each of the microarray (Stage 1) and qRT-PCR (Stage 2) experiments. It is demonstrated how the significance level should be determined for Stage 2, after selecting a fixed percentage of the genes to validate from Stage 1, in order to maximize the sensitivity of detection of differentially expressed genes for a desired overall FDR. The results indicate that most of the available replicates (typically >60%) should be consumed in Stage 1. Even though the optimization scheme assumes independent genes and known variances, simulation results show that this approach is robust to moderate departures from those assumptions. A procedure to optimize a validation experiment, conditional upon an existing microarray assay that was not optimized for two-stage testing, is also introduced. The results indicate that generally liberal significance levels (i.e., alpha > 0.05) could be used for gene-specific Stage 2 tests in typical studies to properly control FDR.
Insights From Breast Cancer Survivors The Interplay Between Context, Epistemology, and Change

This study explored the processes by which a group of breast cancer survivors experienced positive learning and growth from their cancer experiences. The author argues that such learning and growth can be considered transformative learning, especially from ontological perspectives of the theory. The participants’ change process consisted of different types of experiences that can be classified as Crisis, Coping, and Engagement. These types of experiences illustrate a process of adaptation to a new context. The findings suggests that the specific context in which transformative learning occurs has a profound effect on the epistemology used to negotiate that learning and growth, and in turn shapes and informs the types of change that occur.
The microbial analysis of domestic cistern water in the U.S. Virgin Islands

A significant proportion of the water supply in the U.S. Virgin Islands comes from the rainfall which is stored in cisterns. Since cistern water is not part of the public distribution system, it is not covered by the Safe Drinking Water Act (Public Law 93-523). The objective of this study was to determine whether cistern water supplies pose a potential health hazard to their users. The cistern water supplies were studied to assess the types of heterotrophic bacteria, algae, and protozoa that may be present. The bacterial study was directed towards identifying those organisms capable of causing disease in water supplies. Total coliform, fecal streptococcus and Salmonella sp. were enumerated. The presence of coliform bacteria, fecal streptococcus and Salmonella sp. in most of the cistern water supplies suggested a potential health problem. Algae and protozoa were found in several cistern waters, which indicated a high level of microbial diversity. These complex ecosystems suggested a continuous input of carbon and energy sources into the cisterns. The pollution of these cistern water supplies seemed to be of extreme significance, which has been overlooked by those involved in ascertaining the microbial quality of all drinking water in the U.S. Virgin Islands.
An Improved Snare Catheter for Retrieving Embolized Fragments of Polyethylene Tubing

A modification of the doubled-over guide wire technique for retrieval of embolized catheter particles is described. Affixing the flexible end of an exchange guide wire to the outer proximal edge of a No. 6 or 7F cardiac catheter permits easier manipulation of longer catheters, and avoids adherence of the guide wire to the inner catheter lumen.