cssi/SciSciGPT-SciSciNet huggingface dataset:
What Are the Real Rates of Postoperative Complications: Elucidating Inconsistencies Between Administrative and Clinical Data Sources

Background Comparison of quality outcomes generated from administrative and clinical datasets have shown inconsistencies. Understanding this is important because data designed to drive performance improvement are used for public reporting of performance. We examined administrative and clinical data and 2 clinical data sources in 4 surgical morbidity outcomes. Study Design Patients who underwent operations between January 2009 and May 2010 had outcomes compared for postoperative hemorrhage, respiratory failure, deep vein thrombosis (DVT), and sepsis. Three data sources were examined: administrative (Agency for Healthcare Research and Quality [AHRQ] Patient Safety Indicators [PSIs]), a national clinical registry (National Surgical Quality Improvement Program [NSQIP]), and an institutional clinical registry (Cardiovascular Information Registry [CVIR]). Cohen's Kappa (K) coefficient was used as a measure of agreement between data sources. Results For 4,583 patients common to AHRQ and NSQIP, concordance was poor for sepsis (K = 0.07) and hemorrhage (K = 0.14), moderate for respiratory failure (K = 0.30), and better concordance for DVT (K = 0.60). For 7,897 patients common to AHRQ and CVIR, concordance was poor for hemorrhage (K = 0.08), respiratory failure (K = 0.02), and sepsis (K = 0.16), and better for DVT (K = 0.55). For 886 patients common to NSQIP and CVIR, concordance was poor for sepsis (K = 0.054), moderate for hemorrhage (K = 0.27) and respiratory failure (K = 0.4), and better for DVT (K = 0.51). Conclusions We demonstrate considerable discordance between data sources measuring the same postoperative events. The main contributor was difference in definitions, with additional contribution from data collection and management methods. Although any of these sources can be used for their original intent of performance improvement, this study emphasizes the shortcomings of using these sources for grading performance without standardizing definitions, data collection, and management.
Structural trends in the lanthanide trihydroxides

Abstract The hydrous lanthanide oxides and hydroxides comprise a complex series of both amorphous and crystalline compounds. One important member of this system is the hexagonal form of M(OH)3 where M studied here are La, Nd, Sm, Gd, Tb, Dy, Ho, Y and Er. The lattice constants and structure for these nine isotypic compounds has been determined by three-dimensional X-ray diffraction. The space group is P63/m or P63 with two formula units per cell. The metal is 9-coordinate (tri-capped trigonal prism) with two independent metal-oxygen bond distances and three independent oxygenz.sbnd;oxygen bond distances. The metaloxygenoxygen bond distances both exhibit monotonic decreases proceeding from La to Er. The metal to oxygen distances range from 2.588(3) A to 2.403(3) A for MO2 and from 2.551(3) A to 2.439(3) A for MO1. At the low atomic number end of the series the MO1, bond distance is shorter than the MO2 bond distance. The two bond distances become the same at the spherically symmetric gadolinium and switch in relative magnitude as you proceed to erbium. The oxygenoxygen bond distances range from 3.033(5) A to 2.856(5) A for O1O2, 2.992(6) A to 2.826(7) A for O2O2 and 2.900(6) A to 2.710(6) A for the second O1O2 bond distance. Approximate positions for the hydrogen atoms have been found for the M(OH)3 compounds Gd, Dy, Ho, Y and Er. A set of crystal radii for the lanthanides La, Nd, Sm, Gd, Tb, Dy, Ho and Er has been derived.
Role of focal adhesion kinase in integrin signaling.

Abstract Integrins are the major cell surface receptors for extracellular matrix molecules, which play critical roles in a variety of biological processes. Focal adhesion kinase has recently been established as a key component of the signal transduction pathways triggerred by integrins. Aggregation of FAK with integrins and cytoskeletal proteins in focal contacts has been proposed to be responsible for FAK activation and autophosphorylation by integrins in cell adhesion. This may be achieved by FAK interaction with talin or other cytoskeletal proteins that in turn associate with the cytoplasmic domain of integrin β subunits. Autophosphorylation of FAK at Y397 leads to its association with Src, resulting in activation of both kinases. The activated FAK/Src complex acts on potential substrates tensin, paxillin and p130cas. Besides cytoskeletal regulation, FAK phosphorylation and/or binding to paxillin and p130cas may trigger downstream activation of MAP kinase by the adoptor protein Crk. Src association with FAK may also lead to its phosphorylation of other sites on FAK, including a binding site for Grb2. Cell adhesion-dependent association of FAK and Grb2 may provide a mechanism by which MAP kinase is activated in cell adhesion. PI 3-kinase has also been shown to bind FAK in a cell adhesion-dependent manner at the major autophosphorylation site Y397. This association could lead to activation of PI 3-kinase and its downstream effectors. Recent results from a number of different approaches have shown that integrin signaling through FAK leads to increased cell migration on fibronectin as well as potentially regulating cell proliferation and survival.
Knowledge, attitudes, cultural, social and spiritual beliefs on healthseeking behaviors of Gambian adults with HIV/AIDS

HIV/AIDS continues to grow exponentially in sub-Saharan Africa. Early HIV/AIDS care is essential for early interventions to increase quality of life and reduce mortality. The objectives of the study were: (1) to determine the relationship among attitudes, spiritual beliefs, cultural beliefs, social beliefs and knowledge on health-seeking behaviors (HSB) of Gambian adults living with HIV/AIDS; and (2) to provide preliminary data on psychometric characteristics of the newly developed HIV/AIDS Knowledge, Attitudes and Beliefs Patient Questionnaire. The descriptive design included 93 adults aged 21 to 65 years. Correlation and hierarchical regression analyses were used. Bivariate analyses demonstrated significant relationships between all five variables and HSB at p </=.03. Additionally, 11% of the variance in HSB was explained by the combined contribution of the five variables. Attitudes significantly contributed to the variance, F(1, 90) =4.865; p =.03; spiritual beliefs, though not statistically significant, had clinical significance. The unique contributions of this study are the separation of the variable attitudes from beliefs and knowledge, which independently explained HSB. Spiritual beliefs and attitudes are critical in developing appropriate HIV/AIDS interventions. Furthermore, the HIV/AIDS Knowledge, Attitudes, and Beliefs Patient Questionnaire provides a valid means for measuring attitudes, beliefs and knowledge of HIV/AIDS for use in future research.
Phase diagram and phase transitions of Krypton on graphite in the extended monolayer regime

We report high resolution x-ray diffraction studies of the structures and phase transitions of monolayer krypton, adsorbed on both powder and single crystal graphite substrates. A comprehensive series of powder diffraction profiles is used to construct the two dimensional phase diagram. The melting of the $$\sqrt 3 x\sqrt 3$$ commensurate solid is shown to be strongly first order throughout the region where tricritical behavior was previously thought to occur; fluid solid coexistence extends up to the termination of the commensurate phase at 130 K. A disordered weakly incommensurate phase is shown to be a reentrant fluid, a system which may be described as a disordered network of domain walls and which evolves continuously into a more conventional 2D fluid. This evolution is marked by the disappearance of satellite peaks which are caused by the modulation of the overlayer by the substrate. The freezing of the reentrant fluid into the commensurate phase is shown to be consistent with a chiral Potts transition, its freezing into the incommensurate solid consistent with a dislocation binding transition. Single crystal experiments reveal the orientation of the weakly incommensurate phase. The reentrant fluid is found to have no visible orientational fluctuations, manifesting isotropic diffraction peaks. This is attributed to the strong epitaxy of domain walls. The incommensurate solid is shown to undergo an aligned-rotated transition which is well described by zerotemperature calculations.
Diversity of exposure in television viewing: audience fragmentation and polarization in Guangzhou

Chinese television has gone through tremendous growth and change recently. The new media environment has the potential to reshape patterns of television consumption and, in turn, affect the democratic development of Chinese society. This study examines audience fragmentation and polarization, two measures of diversity of exposure, in Guangzhou by conducting a secondary analysis of people meter data. The results show that structural changes have increased the degree of audience fragmentation and polarization in Guangzhou. Most notably, the rapid development of both overseas and local television services has greatly diminished the audience for national, government operated channels in the market. Overall, though, patterns of audience fragmentation and polarization are more limited than analogous audience behaviors reported in the West. Guangzhou audiences still concentrate on popular programs with general appeals and show very little evidence of forming into “enclaves” that confine their television consumpt...
Retrospective voting: An experimental study

This essay reports on some experiments designed to study two candidate electoral competition when voters are ‘retrospective’ voters. The experiments consist of a sequence of elections in which subjects play the part of both voters and candidates. In each election the incumbent adopts a policy position in a one-dimensional policy space, and voters are paid (on the basis of single peaked utility function over that space) for the position adopted by the incumbent. Neither voters nor candidates are informed of the voter utility functions, and the only information received by the voter is the payoff he has received from the present and previous incumbent administrations. Despite the severely limited information of candidates and voters, we find that, generally, candidates converge toward the median voter ideal point.
Laparoscopic renal cryoablation: Acute and long-term clinical, radiographic, and pathologic effects in an animal model and application in a clinical trial

ABSTRACT Objectives: To evaluate renal cryosurgery by studying the feasibility of laparoscopic delivery and the radiographic characteristics and histopathologic effects in a porcine model using dif...
The orientation and motion of the predawn current sheet and Jupiter's magnetotail

From the observed times when Pioneer 10 and Voyager 1 observe particle flux maxima and minima and when the magnetic field strength is at minimum a geometric description of the current sheet in Jupiter's magnetosphere is derived. It lags the planetary rotation by an angle delta which varies as a function of radial distance as delta equals 22 deg + 0.80 (r - 16.3). The maximum latitude of the current sheet is roughly 10 deg inside of 60 Jovian radii and decreases beyond. Thus there is a hinge point near 60 Jovian radii. The position of the hinge point moves in response to the external solar wind pressure variation. The variation of delta(r) is discussed theoretically and how it is related to the magnetic field topology and plasma flow is shown. It is concluded that the distant field lines do not corotate with Jupiter and that the Alfven speed at 50 Jovian radii is of the order of 1500 km/s. The topology of the current sheet is affected by centrifugal forces, outward mass transport and solar wind-magnetosphere interaction. It is shown how these effects can be related to different current systems.
Review of Kim Paffenroth,Gospel of the Living Dead

Richard Walsh reviews Kim Paffenroth’s Gospel of the Living Dead: George Romero’s Visions of Hell on Earth . Waco, Texas: Baylor University Press; 2006.
Prophylaxis in dermatologic patients receiving immunosuppressive therapy

Despite substantial advances in developing more selective agents, immunosupressive therapy is still associated with serious complications. This article summarizes the preventive measures that can significantly reduce the incidence or severity of immunosupressive side effects.
Physiological Arousal and Attention in Veterans with Posttraumatic Stress Disorder

Psychophysiological reactivity has been well documented in WWII, Korean Conflict, and Vietnam veterans with posttraumatic stress disorder (PTSD). In addition, these individuals have demonstrated cognitive impairments within the domains of attention, concentration, new learning, and memory. However, there has been no research examining the impact of physiological arousal on attention in individuals with PTSD. This study documents the level of physiological arousal and associated disruption of attentional abilities in 28 Persian Gulf War veterans (18 without PTSD or other psychopathology and 10 with PTSD). This population represents a group of combat trauma victims who experienced a relatively acute onset of PTSD, thus providing a unique opportunity to compare prior psychophysiological and cognitive results with a group of veterans who manifested a recent onset of PTSD. Results indicated relatively comparable psychophysiological reactivity and arousal between Persian Gulf War veterans with PTSD and Persian Gulf War veterans without PTSD. Furthermore, attentional processes of veterans with PTSD were not more disrupted than in comparison soldiers. Results suggest that the intensity and chronicity of the disorder may impact physiological arousal and disruption of cognitive functioning. Following Persian Gulf War veterans with PTSD over time may reveal that psychophysiological arousal becomes more pronounced with chronicity, perhaps as memory networks become strengthened and/or neuroendocrine systems become increasingly disrupted.
Identifying population health faculty in U.S. medical schools.

Abstract Context: An Association of American Medical Colleges (AAMC) panel has proposed the components of a population health (PH) curriculum for U.S. medical schools. Do schools have the trained faculty to teach these subjects well? Objective: Determine the number and location of full-time medical school faculty formally trained in the population health sciences through an MPH degree, a public health (PH)–related doctoral degree, a residency in preventive medicine, or board certification in preventive medicine in 1990 and 1998. Design: This is a descriptive study based on the AAMC Faculty Roster System that includes information about all full-time U.S. medical school faculty. Results: In 1998, 2007 out of a total of 88,782 full-time medical school faculty had MPH degrees and 1214 had a PH-related doctoral degree. A total of 484 faculty had residency training in preventive medicine while 279 had passed the preventive medicine board examination. Faculty with these various degrees are distributed among multiple departments. Since 1990, most growth in new faculty formally trained in the population health sciences has been in family medicine, internal medicine, and pediatrics rather than preventive medicine. Conclusions: Full-time medical school faculty with MPH degrees and PH-related doctoral degrees have grown faster than total faculty since 1990. Faculty with residency training or board certification in preventive medicine have grown much more slowly. Faculty formally trained in the PH sciences are distributed among departments of preventive medicine, family medicine, internal medicine, and pediatrics, among others. Unfortunately, a significant number of medical schools have very few faculty formally trained in the PH sciences. The implications of this distribution for the education of medical students are discussed.
Skew Diagrams and Ordered Trees

We use a known combinatorial argument to prove that among all ordered trees the ratio of the total number of vertices to leaves is two. We introduce a new combinatorial bijection on the set of these trees that shows why this must be so. Ordered trees are then enumerated by number of leaves, total path length, and number of vertices to obtain q-analogs of Catalan numbers. The results on ordered trees are then readily transferred by the skew diagrams to help enumerate parallelogram polyominoes by their area, perimeter, and other statistics.
SU‐DD‐A4‐06: Registration of Volumetric KV Or MV Cone Beam CT with Fan Beam CT

Purpose: Kilovoltage (kV) cone beam CT(CBCT) provides the patient's volumetric information and is valuable for patient positioning verification. An important step in this application is the registration of CBCT acquired at simulation or before treatment with the planning CT (PCT). The purpose of this work is to investigate several specific issues involved in CBCT‐TPCT registration and develop an effective algorithm to effectively utilize the volumetric imaging system for IGRT.Method and Materials: The PCT data were acquired using Picker PQ5000 scanner, and the CBCTimages were obtained using Varian Trilogy OBI system. The image quality of CBCT is generally poor as compared with conventional CT: Low soft tissuecontrast, artifacts/distortions, and limited width/length present practical problems for its clinical application. A BSpline based non‐rigid image fusion software was implemented to provide voxel‐to‐voxel matching between PCT and CBCT.Results: For the phantom study, the quality of CBCT has little effect on the registration and the CBCT‐PCT mapping was relatively straightforward because of the absence of motion artifacts. Examination of “bony” landmarks indicated that an accuracy less than 2mm was achievable. The patient registrations were complicated by artifacts and, in the cervix case, the limited field size of CBCT. While the bony landmarks can be registered to within 2mm, the motion artifacts complicated registration and caused a large uncertainty in the PCT‐CBCT mapping. Conclusion: Low soft tissuecontrast and artifacts of CBCT posed a challenge for CBCT‐PCT registration. While continuous effect is needed to improve the CBCT, a robust registration tool that can cope with specific issues of CBCT is highly desirable to fully exploit the volumetric CBCT technology.
Improved correlation corrections to the local-spin-density approximation

The accurate correlation energies for the para- and ferro-magnetic states of the electron liquid calculated by Ceperley and Alder were recently used by Vosko, Wilk, and Nusair to produce a new correlation-energy density of increased accuracy and proper limiting behavior in the metallic density regime (${r}_{s}\ensuremath{\le}6$). In the present work, the correlation potential in the local-spin-density approximation (LSDA) is derived from the correlation-energy-density representation of Vosko et al. Characteristics of the new exchange-correlation model are compared with those of the LSDA model of Gunnarsson and Lundqvist. Specific comparison is made between these models and exact results in the treatment of atomic and molecular hydrogen. Since the new treatment of correlation primarily affects the region of small ${r}_{s}$, which is exchange dominated, correlation corrections are small compared with errors in the exchange energy. Thus, in light atoms the improved correlation model leads to a reduced cancellation of error between exchange and correlation energies, emphasizing the necessity for improved exchange treatment. For more homogeneous systems, the model should offer real improvement. The present results obtained with precise treatment of correlation within the prescription of Vosko et al. serve to define the present limitations of the LSDA and indicate the importance of nonlocal corrections, particularly for atoms.
Interactions of chlorpyrifos and methyl mercury: a mechanistic approach to assess chemical mixtures

The mechanism of interaction between chlorpyrifos, an organophosphate insecticide, and methyl mercury was assessed utilizing the amphipod, Hyalella azteca. Previous studies have demonstrated that chlorpyrifos and methyl mercury interact additively with survival as the endpoint. In addition, exposure to chlorpyrifos and methyl mercury increased the accumulation and decreased the elimination of methyl mercury. To further examine the mechanism responsible for these interactions, the in vivo and in vitro inhibition of acetylcholinesterase enzyme activity was assessed following exposure to methyl mercury and chlorpyrifos. In vivo, methyl mercury antagonized the effects of chlorpyrifos on acetylcholinesterase inhibition. Additional studies demonstrated that methyl mercury did not affect the in vitro bioactivation of chlorpyrifos or the subsequent inhibition of acetylcholinesterase enzyme activity. Chemical-chemical interactions were examined utilizing chromatographic techniques and suggested the formation of a chlorpyrifos-methyl mercury complex. The formation of this complex may result in increased accumulation of methyl mercury, apparent additive toxicity, and protection against chlorpyrifos-mediated acetylcholinesterase inhibition.
Transhepatic Embolization of Varices

Percutaneous transhepatic embolization of varices (PTEV) has proved to be effective in the control variceal bleeding, particularly in Child’s Class C Category patients whose bleeding was not adequately controlled by pitressin perfusions. PTEV, using Gel-foam soaked in sodium tetradecyl sulfate, controlled acute variceal bleeding in 71–95% of patients and appears to be more effective as an embolizing agent than bucrylate, which controlled 43–57%. Considering the poor condition of the patients particularly during acute bleeding episodes, PTEV is a relatively safe therapeutic procedure that buys time for the surgeons to perform a decompressive shunt electively as definitive surgery. A one-year recurrent bleeding rate of 30% and a two year recurrence of 37.5% was noted. Thus, for long term control of variceal bleeding, a surgical decompressive shunt is recommended in addition to PTEV.
A facial recognition technique employing Frequency Domain Thresholding and Quantization (FD-TQ)

A facial recognition technique employing Frequency Domain Thresholding and Quantization (FD-TQ) is presented in this paper. The algorithm has attractive properties with respect to storage requirements and computational complexity in both the training and testing modes, which make the technique particularly suitable for large data bases. The new algorithm is applied to ORL, Yale and FERET data bases. The experimental results confirm the significant reduction in the storage and computational requirements compared with recently reported techniques, without sacrificing the recognition accuracy.
Resources for Agile Software Development in the Software Engineering Course

Agile software development is an emerging topic in software engineering. Industrial use of agile techniques is growing faster than our educational resources are being updated. Using an open courseware platform, OpenSeminar, we provide course resources for software engineering students about agile software development methodologies. These resources include readings, sites, lab exercises, lectures, examples, testing practices, and testing frameworks
"Managing" the poor: neoliberalism, Medicaid HMOs and the triumph of consumerism among the poor.

In order to explore the contradictions of neoliberal health policy, this article examines Medicaid managed care in Philadelphia. At the federal and state levels, government is increasingly promoting private‐sector market‐based strategies over policies formerly associated with the welfare state, arguing that the former are the most effective means of achieving economic growth and guaranteeing social welfare. A prime example of this shift, Medicaid managed care is a policy by which states contract with private‐sector health maintenance organizations to provide health coverage to the poor. Drawing on ethnographic and historical data, this paper shows how Pennsylvania's Medicaid managed care program has created access barriers for poor Philadelphians. It also illustrates how ideologies that justify this policy shift serve to mask its detrimental effects on the poor. By contrasting the state's consumerist model with one group's protest efforts, this article calls into question the neoliberal ideology that unde...
The killer Kindle

Purpose – The purpose of this paper is to review Amazon's Kindle, and to describe intersections between it, smart phones, and Google Books.Design/methodology/approach – The article is designed as an opinion piece on the nature of electronic books in academia.Findings – The article suggests e‐books will increase in popularity over time, but that the business model for individual download of e‐books will need to support institutional purchase.Originality/value – The article should generate views, both in support of and in opposition to, the claims of the author; it should serve as a discussion starter.
Activation-controlled hydrogen abstraction by benzophenone triplet

Abstract Through nanosecond flash photolysis measurements, activation energies for hydrogen abstraction by benzophenone triplet have been shown to correlate with solvent molecular structure. We demonstrate that two successive processes result in photoproduct generation. One, triplet quenching, is independent of macroscopic viscosity, and is not simply reflected in the observed quantum yield. The second process involves separation of two caged radicals, and does not occur in rigid media.
Unemployment and property crime: a target-specific assessment of opportunity and motivation as mediating factors

Most recent unemployment-crime (U-C) research is informed by the possibility that unemployment could both increase motivation for crime and decrease criminal opportunities. The mediating links of motivation and opportunity, though often assumed, have almost never been measured. We directly test for the potential mediating effects of opportunity and motivation using county-level data for target-specific crime rates such as convenience store robberies, motorcycle thefts, etc. We link these with data on the supply and value of corresponding crime targets (e.g., number and annual sales of convenience stores). Opportunity levels were generally unrelated to property crime rates and do not appear to mediate the U-C relationship.
Boronic acid-modified DNA that changes fluorescent properties upon carbohydrate binding

A long wavelength boronic acid-modified TTP (NB-TTP) has been synthesized and enzymatically incorporated into DNA. Such DNA shows intrinsic fluorescent changes upon carbohydrate addition.
Effect of extracellular matrix on PC 12 cell shape and dopamine processing

Substrates of various origins can affect the morphology, growth and functional properties of many cell types. PC 12 cells (a clonal line of rat pheochromocytoma) synthesize, store and secrete dopamine as well as other transmitters. These cells are rounded and loosely attached when cultured on plastic, but flatten and spread extensively when cultured on an extracellular matrix secreted by bovine corneal endothelial cells. We determined that spontaneous dopamine release into culture medium was significantly higher from cells which were flattened on matrix, and that the cellular content of dopamine was less than in cells which were maintained on plastic. The higher levels of medium dopamine in matrix cultures were not due to an increase in cellular attachment or growth as determined by [3H]thymidine incorporation. A variant of PC 12 cells which is flat on plastic showed no change in cell shape or dopamine release when plated on matrix. These experiments suggest that extracellular matrix promotes a change in cell shape and that this change in the physical arrangement of these cells alters their release and storage of dopamine.
Overcoming Past Obstacles to Insurance in the New EU Countries

The newest EU member countries in Central and Eastern Europe went through a rapid transition from state to market direction of economic and financial affairs as well as of enterprises and social arrangements, including insurance. As incentive structures, property rights, rules of competition, and the assignment of liabilities changed, so did the risks associated with private operations and investments. This essay looks at some of the unexpected risk exposures and the means of coping with rapid change in incomplete financial markets largely through the eyes of a leading participant in the process.
Particle-physics implications of a recent test of the gravitational inverse-square law.

We use data from our recent search for violations of the gravitational inverse-square law to constrain dilaton, radion, and chameleon exchange forces as well as arbitrary vector or scalar Yukawa interactions. We test the interpretation of the PVLAS Collaboration effect and a conjectured ``fat-graviton'' scenario and constrain the ${\ensuremath{\gamma}}_{5}$ couplings of pseuodscalar bosons and arbitrary power-law interactions.
Philosophy of Music in the Consolatio of Boethius

WHEN Boethius first sketches his memorable classification of music, he promises to say more later about musica mundana and humana,' but he does not do so in De musica itself,2 and scholars have thought that he never returned to the subject at all.' What I would like to suggest now is that Boethius does take up the old interest again in his last and greatest work, De consolatione Philosophiae, but in a way quite different from that of De musica. When he makes the early promises, he implies that he will say more about world and human music in physical and mathematical terms, but when he fulfills them indirectly in the Consolatio, he does so ethically and metaphysically, which is, perhaps, how one might expect a philosopher awaiting death to use his rich store of knowledge. Boethius does more, however, than simply carry out his early promises. He permeates the Consolatio with ideas about music. Indeed, the work may be said to have a main theme that is musical and to embody a more complete philosophy of music than De musica itself. It offers another striking precedent, therefore, like the Somnium Scipionis and the De nuptiis Philologiae et Mercurii, for mediaeval poets such as Alan of Lille, Dante, Machaut, and Chaucer, to use ideas about music thematically in their own imaginative works, as scholars are recognizing more and more that they do.4 Thus the Consolatio is a major instance of the close relations among philosophy, music, and literature in late classical and mediaeval culture, but an instance that has been overlooked by scholars in all three disciplines.5 We will understand better what Boethius does in the Consolatio if we first look briefly at the main philosophic ideas about music in De musica and De arithmetica, and for this purpose we can reduce them to four heads: (1) the origin of music, (2) the definitions of music and the true musician, (3) the classification of music, and (4) the moral analysis of instrumental music. The origin of music, Boethius tells
Substrate effects on the growth of carbon nanotubes by thermal decomposition of methane

Abstract A systematic investigation into the growth of single-walled carbon nanotubes (SWNTs) on thin metallic films deposited on various substrates was performed. Aluminum–iron–molybdenum multi-layer thin films were deposited on various substrates to determine which substrates promote the growth of SWNTs over multi-walled nanotubes (MWNTs) during the decomposition of methane gas. It was determined that the substrate employed as the supporting material for the Fe thin film catalyst has a strong effect on controlling the growth of either SWNTs or MWNTs, with clear trends noticeable. The ideal substrate for SWNT growth was a spun-on alumina film, while, single crystal substrates promoted the growth of mixed SWNTs and MWNTs. All remaining substrates grew primarily MWNTs.
Structures, Rugged Energetic Landscapes, and Nanothermodynamics of Aln (2 ≤ n ≤ 65) Particles

Metal nanoparticles are important in several emerging technologies, but their size-selected thermodynamic properties are hard to obtain from experiment. We have characterized the energetic and structural properties of unsupported neutral Aln (2 ≤ n ≤ 65) particles (clusters and nanoparticles) via molecular dynamics quenching simulations with a recently validated many-body analytic potential. For each particle size (n), the global minimum-energy structure, the distribution of the local energy minima, and the finite-temperature thermodynamics have been calculated, the latter by evaluating ∼100 000 rovibrational partition functions for the low-energy isomers of the various particles. This analysis demonstrates that the dominant structures of clusters and nanoparticles depend on temperature as well as particle size and that one must consider statistical mechanics as well as electronic structure in determining the dominant structures, stabilities, and properties of nanoparticles. As a particularly dramatic exa...
VLA Observations of the Nearby Merger NGC 4038/4039: H II Regions and Supernova Remnants in the “Antennae”*

We present 6 and 4 cm radio images of the inner disks of the nearby merger pair NGC 4038 and NGC 4039 at resolutions between ~ 1'' and 26, or ~ 100 and 260 pc. We detect numerous compact radio sources embedded in more diffuse radio emission; the compact radio sources produce ~ 12% and ~ 25% of the 6 and 4 cm radio emission in the system, respectively. The strongest radio continuum emission occurs between the galaxies, at an optically unremarkable location near but not coincident with an extremely red cluster detected by Whitmore & Schweizer. The radio peak is at a location of intense star formation (as detected in the mid-IR) and of dense molecular gas. We identify 115 individual compact 6 cm radio sources and 63 individual 4 cm sources in the system, to a limiting luminosity of ~ 2 × 1018 W Hz-1, or ~ 4 times the luminosity of Cas A; 90% of the 6 cm sources and 67% of the 4 cm sources are unresolved in these observations. Of the strongest sources, for which the flux densities are large enough to measure spectral indices with reasonable errors, one-third have nominally flat radio spectra, indicating that they are dominated by thermal radio emission from H II regions, and two-thirds have nominally steep spectra dominated by nonthermal emission from supernova remnants. For the compact sources dominated by thermal emission, we derive typical masses of 104 to 105 M⊙ in massive young stars. Using reasonable assumptions about source sizes, we estimate associated ionized gas masses of 103 to 104 M⊙. A comparison with the ~ (2–5) × 103 M⊙ typical optical clusters detected recently by Whitmore et al. suggests that the thermal radio sources detected here may be composed of tens of these typical young star clusters or else that they are more like the individual massive 105–106 M⊙ Whitmore et al. clusters. The strongest thermal radio source is associated with none of the Whitmore et al. clusters but is coincident with strong CO and 15 μm emission, implying that massive star clusters are still enshrouded by dust in this region. The second strongest thermal source is near several optical clusters, suggesting that these clusters are just now emerging from their birth cloud and are clearing away the surrounding material. Estimates of stellar ages and sound speeds indicate that we do not see star formation propagating in this system; rather, the star formation sequence is probably related to more global properties of the interaction. From the steep-spectrum sources, we derive a total system supernova rate of 0.2–0.3 yr-1, about an order of magnitude larger than that expected from the currently observed O star population. This suggests that a large number of O stars may have formed in the system in a short-lived burst, less than 106 yr in duration and about 3–4 Myr ago.
Nicotine-induced depolarization of cerebral cortical synaptosomes is dependent upon sodium

Abstract Earlier studies from this laboratory demonstrated that activation of nicotinic cholinergic receptors of cerebral cortical synaptosomes of the rat produced a decrease in the accumulation of [3H]tetraphenylphosphonium ([3H]TPP+) as a result of a decreased synaptosomal membrane potential. In the present study, the role of sodium in the effect of nicotine on the accumulation of [3TPP+ and the estimated potential difference was explored. Replacement of buffer sodium with either sucrose or N-methyl- d -glucamine (NMDG), attenuated the depolarization produced by the sodium channel activator, veratridine and had no effect on potassium-induced depolarization. The effect of nicotine on accumulation of [3H]TPP+ into cerebral cortical synaptosomes was abolished in sucrose buffer and attenuated in NMDG buffer. 1,1-Dimethyl-4-phenylpiperazinium iodide (DMPP; 30μM) produced a small increase in the influx of 22Na+ into cerebral cortical synaptosomes. The effect of DMPP on the influx of 22Na+ was not blocked by tetrodotoxin. These results support the hypothesis that the nicotinic cholinergic receptor in the brain, functions as a sodium ionophore and further demonstrate that accumulation of synaptosomal [3H]TPP+ provides a simple tool with which to assess the effect of nicotine on sodium permeability through open nicotinic cholinergic receptor ionophores.
On a Theta Correspondence with Respect to a Quadratic Extension

Abstract Let F be a totally real algebraic number field, and let E be a totally real quadratic extension of F . In this article we establish a theta correspondence between certain automorphic forms defined with respect to a quaternion algebra over E and Hilbert modular forms defined with respect to F . Given such a quaternionic form, say h , the main theorem expresses the Fourier coefficients of its theta lift in terms of periods of h . The results in this paper generalize some theorems of Shimura.
"Floating" MMPI profiles and DSM-III diagnoses.

DSM-III diagnoses of 55 hospitalized psychiatric male patients who produced “floating” MMPI profiles were obtained via retrospective chart review. A prospective study of 16 then was conducted to cr...
A novel method for measurement of intravesicular pH using fluorescent probes.

A method for the measurement of intravesicular pH of phospholipid vesicles and gastric microsomes is described. The present method makes use of the well characterized pH-dependent shift of the emission maximum of two fluorescent amines, quinine and acridine. As the probes distribute into the intravesicular space, according to the existing pH gradient, they respond to the acidic environment and emit fluorescence at a longer wavelength than the external probes which sense the more alkaline medium. By measuring both the decrease in the alkaline fluorescence peak and the enhancement of the acidic peak, direct determination of the internal pH can be obtained. This method has the advantages of giving a positive signal (enhancement of fluorescence instead of quenching), measuring intravesicular pH directly without the need of independent measurement of the volume of the H+ space, and also enabling the possible use of a much lower probe concentration than that required by the fluorescence-quenching method. The accuracy of the present method was quantitatively verified using phospholipid vesicles as a well defined model system. Application to biological systems was demonstrated using gastric microsomes which actively transport H+ into the microsomal space via an H+-K+ exchange ATPase system. The reasoning of the present method is also extended to the monitoring of internal alkaline pH gradient by using a fluorescent weak acid, o-hydroxycinnamic acid. Some general criteria for the future search for better pH gradient probes are presented.
Preterm rupture of the membranes: Combination therapy

Preterm rupture of the membranes poses perhaps the greatest threat to perinatal survival. Unfortunately, the literature leaves us in a quandry as to the management of the problem. At the Medical University of South Carolina for the past 3 years, aspects of both active and passive management have been used. Vaginal pool phospholipid analysis, the use of corticosteroids whenever appropriate, and tocolysis (in an attempt to gain 48 hours) were used in 96 consecutive patients with premature rupture of the membranes between 26 and 36 weeks' gestation. Decisions about delivery were dictated by spontaneous onset of labor and/or evidence of chorioamnionitis. This regimen prolonged gestation an average of 4.6 days. Maternal and neonatal infectious morbidity was uncommon. Clinical chorioamnionitis was diagnosed in 5.2% of mothers, and only 8.5% of all neonates had evidence of serious infection. Respiratory distress syndrome was seen in 12.8% of neonates. There were only three perinatal deaths, and most babies (92.5%) were discharged without residual problems (average hospital stay, 18.1 days). A detailed analysis of the group by gestational age categories will be presented.
Construction of a 1.2-Mb contig including the citrus tristeza virus resistance gene locus using a bacterial artificial chromosome library of Poncirus trifoliata (L.) Raf.

The citrus tristeza virus resistance gene (Ctv) is a single dominant gene in Poncirus trifoliata, a sexually compatible relative of citrus. To clone this gene, a bacterial artificial chromosome (BAC) library has been constructed from an individual plant that was homozygous for Ctv. This library contains 45 696 clones with an average insert size of 80 kb, corresponding to 9.6 genome equivalents. Screening of the BAC library with five chloroplast DNA probes indicated that 0.58% of the BAC clones contained chloroplast-derived inserts. The chromosome walk across the Ctv locus was initiated using three closely linked genetic markers: C19, AD8, and Z16. The walk has been completed and a contig of ca. 1.2 Mb was constructed. Based on new data, the genetic map in the Ctv region was revised, with Ctv being located between AD8-Z16 and C19 at distances of 1.2 and 0.6 cM, respectively. Utilizing DNA fragments isolated from the contig as RFLP markers, the Ctv locus was further mapped to a region of ca. 300 kb. This contig contains several putative disease-resistance genes similar to the rice Xa21 gene, the tomato Cf-2 gene, and the Arabidopsis thaliana RPS2 gene. This library will therefore allow cloning of Ctv and other putative disease-resistance genes.
Prospective teachers’ reasoning and response to a student’s non-traditional strategy when dividing fractions

Recognizing meaning in students’ mathematical ideas is challenging, especially when such ideas are different from standard mathematics. This study examined, through a teaching-scenario task, the reasoning and responses of prospective elementary and secondary teachers to a student’s non-traditional strategy for dividing fractions. Six categories of reasoning were constructed, making a distinction between deep and surface layers. The connections between the participants’ reasoning, their teaching response, and their beliefs about mathematics teaching were investigated. We found that there were not only differences but also similarities between the prospective elementary and secondary teachers’ reasoning and responses. We also found that those who unpacked the mathematical underpinning of the student’s non-traditional strategy tended to use what we call “teacher-focused” responses, whereas those doing less analysis work tended to construct “student-focused” responses. These results and their implications are discussed in relation to the influential factors the participants themselves identified to explain their approach to the given teaching-scenario task.
Chaos: A potential problem in the biological control of insect pests

Erratic variations are normally observed in the populations of insect pests that destroy crop plants. To establish a scientific basis for developing effective control procedures, we have developed a model system for the European Corn Borer (ECB) (Ostrinia nubilalis) for which extensive field data, as well as laboratory results, have been accumulated during the past four decades. The model includes both a natural ECB pathogen and a genetically engineered toxin-producing agent as possible means of biological control. Our aim was to determine the conditions that could cause the population to vary erratically, as observed in the field. The erratic behavior in our simulations was analyzed to determine whether it is chaotic; chaos is a distinct type of erratic behavior which shows extreme sensitivity to initial conditions, i.e., the starting size of the population. Our simulations show that an increase in the death rate of the infected ECB, or a decrease in the birth rate of uninfected ECBs from infected ones, variables that are known to be affected by weather conditions, can induce a chaotic regime in which ECB population peaks reach values far higher than before chaos set in. Population peaks are even greater in the presence of both biological control agents. The results show that a biological control regime cannot be effective under conditions that induce chaotic population dynamics. Microcosm studies could be used to determine whether this situation would occur in the field.
Unequal Trajectories: Racial and Class Differences in Residential Exposure to Industrial Hazard

The unequal exposure to industrial hazards via differential residential attainment and/or differential sitings of toxic facilities is a long-standing environmental justice issue. This study examines individual trajectories of residential exposure to the risk of industrial hazard over nearly two decades. Using a latent class growth analysis on longitudinal geocoded data merged with the neighborhood-level pollution measures, we discover large racial differences in trajectories of pollution exposure. A majority of individuals are exposed to above-average pollution levels at some point during the study period, but blacks are more likely than whites to experience persistent exposure to high pollution. These differences are only partially explained by racial differences in suburban neighborhood attainment, socioeconomic status, and the frequency of inter-neighborhood moves. Immobile blacks also saw their exposure increase.
Reconciling different models of forebrain induction and patterning: a dual role for the hypoblast.

Several models have been proposed for the generation of the rostral nervous system. Among them, Nieuwkoop's activation/transformation hypothesis and Spemann's idea of separate head and trunk/tail organizers have been particularly favoured recently. In the mouse, the finding that the visceral endoderm (VE) is required for forebrain development has been interpreted as support for the latter model. Here we argue that the chick hypoblast is equivalent to the mouse VE, based on fate, expression of molecular markers and characteristic anterior movements around the time of gastrulation. We show that the hypoblast does not fit the criteria for a head organizer because it does not induce neural tissue from naive epiblast, nor can it change the regional identity of neural tissue. However, the hypoblast does induce transient expression of the early markers Sox3 and Otx2. The spreading of the hypoblast also directs cell movements in the adjacent epiblast, such that the prospective forebrain is kept at a distance from the organizer at the tip of the primitive streak. We propose that this movement is important to protect the forebrain from the caudalizing influence of the organizer. This dual role of the hypoblast is more consistent with the Nieuwkoop model than with the notion of separate organizers, and accommodates the available data from mouse and other vertebrates.