cssi/SciSciGPT-SciSciNet huggingface dataset:
Analysis of longitudinal quality-of-life data in high-risk operable patients with lung cancer: Results from the ACOSOG Z4032 (Alliance) multicenter randomized trial

Abstract Background Prior studies have suggested that low baseline quality-of-life (QOL) scores predict worse survival in patients undergoing lung cancer surgery. However, these studies involved average-risk patients undergoing lobectomy. We report QOL results from a multicenter trial, American College of Surgeons Oncology Group Z4032, which randomized high-risk operable patients to sublobar resection (SR), or SR with brachytherapy, and included longitudinal QOL assessments. Methods Global QOL, using the 36-item Short-Form Health Survey (SF36), and the dyspnea score from the University of California, San Diego Shortness of Breath Questionnaire (SOBQ) scale, was measured at baseline, 3, 12, and 24 months. SF36 physical component summary (PCS) and mental component summary (MCS) scores were standardized and adjusted for age and gender normals, with scores Results Two hundred twelve eligible patients were included. There were no significant differences in baseline QOL scores between arms. Median baseline PCS, MCS, and SOBQ scores were 42.7, 51.1, and 70.8, respectively. There were no differences in grade-3+ AEs, overall survival, or recurrence-free survival in patients with baseline scores ≤median versus >median values, except for a significantly worse overall survival for patients with baseline SOBQ scores ≤median value. There were no significant differences between the study arms in percentage change of QOL scores from baseline to 3, 12, or 24 months. Further comparison combining the 2 arms demonstrated a higher percentage of patients with a ≥10-point decline in SOBQ scores with segmentectomy compared with wedge resection (40.5% vs 21.9%, P = .03) at 12 months, with thoracotomy versus video-assisted thoracic surgery (VATS) (38.8% vs 20.4%, P = .03) at 12 months, and T1b versus T1a tumors (46.9% vs 23.5%, P = .020) at 24 months. A ≥10-point improvement in PCS score was seen at 3 months with VATS versus thoracotomy (16.5% vs 3.6%, P = .02). Conclusions In high-risk operable patients, poor baseline QOL scores were not predictive for worse overall or recurrence-free survival, or for higher risk for AEs following SR. VATS was associated with improvement in physical function at 3 months, and improved dyspnea scores at 12 months, lending support for the preferential use of VATS when SR is undertaken.
Characterization of electron beam crosslinked poly(styrene‐block‐ethylene‐co‐butylene‐block‐styrene)

A saturated triblock copolymer, poly(styrene-block-ethylene-co-butylene-block-styrene) was chemically crosslinked using trimethylol propane trimethacrylate, TMPTM, and subjected to electron beam radiation. The gel percent, Gehman ten second modulus, and stress relaxation were measured to characterize the materials as a function of crosslinker concentration and radiation level. A time-temperature super-position master curve was generated at 63°C for 3 percent TMPTM and 5 Mrads of radiation, which indicated rubbery plateau behavior at long times of measurement, as opposed to the uncrosslinked material, which continued to creep and flow. The main locus of crosslinking was within the polystyrene phase, which explains reduced creep and stress relaxation only for long times of measurement and/or high temperatures. Based on shifts of the glass transition temperatures, it was estimated that 11 to 16 percent poly(ethylene-co-butylene) was dissolved in the polystyrene phase.
Objective assessment of image quality. II. Fisher information, Fourier crosstalk, and figures of merit for task performance

Figures of merit for image quality are derived on the basis of the performance of mathematical observers on specific detection and estimation tasks. The tasks include detection of a known signal superimposed on a known background, detection of a known signal on a random background, estimation of Fourier coefficients of the object, and estimation of the integral of the object over a specified region of interest. The chosen observer for the detection tasks is the ideal linear discriminant, which we call the Hotelling observer. The figures of merit are based on the Fisher information matrix relevant to estimation of the Fourier coefficients and the closely related Fourier crosstalk matrix introduced earlier by Barrett and Gifford [Phys. Med. Biol. 39, 451 (1994)]. A finite submatrix of the infinite Fisher information matrix is used to set Cramer-Rao lower bounds on the variances of the estimates of the first N Fourier coefficients. The figures of merit for detection tasks are shown to be closely related to the concepts of noise-equivalent quanta (NEQ) and generalized NEQ, originally derived for linear, shift-invariant imaging systems and stationary noise. Application of these results to the design of imaging systems is discussed.
A Numerical Investigation on the Effect of Hydrogen and Syngas Addition on the Ignition of JP-8 Surrogates

A numerical study is carried out investigating the effect of hydrogen and syngas addition on the ignition of two JP-8 surrogates, a two-component surrogate and a six-component surrogate. This six-component surrogate has previously been found to accurately simulate the smoke point, volatility, flame temperature profiles, and extinction limits of JP-8, while the two component surrogates has been shown to reproduce the flame structure predicted with the six-component surrogate. CHEMKIN 10101 is used to simulate ignition in a closed homogenous reactor under adiabatic and isobaric conditions. The parameters include temperature ranging from 850–1250 K, pressure of 20 atm, and equivalence ratio ϕ = 1.0. The CRECK-0810 kinetic mechanism, involving 341 species and 9173 reactions, is used to model the ignition chemistry. For the conditions studied, the addition of H2 or syngas in small quantities has no effect on the ignition behavior of either the surrogates or their individual components. Addition of H2 or syngas in larger quantities increases and decreases the ignition delay at low and high temperatures, respectively. For the conditions investigated, the ignition behavior of both the surrogates is predominantly determined by the ignition chemistry of n-dodecane.Copyright © 2012 by ASME
Selection and characterization of ura5 mutants of Histoplasma capsulatum

The combined use of non-aggregating Histoplasma capsulatum strains and a defined medium which allows quantitative plating of the yeast phase has allowed us to select 5-fluoroorotic acid (5-FOA)-resistant mutants of this dimorphic fungus. Approximately two-thirds of the 5-FOA-resistant strains were auxotrophic for uracil; all were deficient in orotidine-5′-monophosphate pyrophosphorylase (OMPpase) activity. One class of OMPpase mutant (α), which retained a low level of OMPpase activity, was auxotrophic in the yeast phase (37°C) but grew slowly in the mycelial phase (25°C) without exogenous uracil. This phenotype was not due to a temperature-sensitive OMPpase activity. Both wild-type and α mutants had a higher OMPpase activity in the mycelial phase than the yeast phase; this increased activity may be sufficient to allow mycelial growth of α mutants.
The Distorted-Wave Born Approach for Calculating Electron-Impact Ionization of Molecules

The distorted-wave Born approximation (DWBA) has been one of the most successful theoretical approaches for treating electron collisions with complicated atoms, and recently the DWBA has been successfully extended to treat electron-impact ionization of molecules. The purpose of this paper is to give an overview of that development and to provide a summary of the recent experimental and theoretical works examining low to intermediate energy electron-impact single ionization of molecules.
Temporal Changes in Serum Progesterone in Aging Female Rats

The effect of age on serum progesterone was measured in female Long-Evans rats. Progesterone concentrations were measured in young (3 months old) and aged (12–24 months old) rats at proestrous, estrous, and diestrous stages of their ovarian cycles. In addition, progesterone was measured in aged noncycling rats with constant estrous, pseudopregnant, or constant diestrous vaginal cytological patterns. Serum progesterone was increased on the afternoon of proestrus in both young and aged rats. Both the magnitude of increase and the proportional increase over basal progesterone were greater in young than in aged animals. The increase in progesterone in young animals compared to aged groups was still present during estrus. Both young and aged groups had a diurnal surge in serum progesterone concentration on diestrous day 2. This increase in progesterone on diestrous day 2 was of greater mganitude and of longer duration in young compared to aged rats. Diurnal patterns of progesterone secretion were absent in age...
Preoperative combined modality therapy for stage III M0 non-small cell lung carcinoma☆

Abstract More than i of all non-small cell lung carcinoma (NSCLC) patients present with locally advanced non-metastatic disease. Despite radiation therapy and surgery the survival of these patients remains poor. In an effort to improve upon these results 33 clinical Stage III M 0 patients from April 1985 through September 1986 were entered into a Phase II study at Rush-Presbyterian-St. Luke's Medical Center. Treatment included 5-FU by continuous infusion, VP-16, cisplatin and concurrent split course radiation therapy followed by surgical resection when possible. The overall clinical response rate is 74%. Fifty-seven percent of the preoperative group of patients went to surgery with a 100% resectability rate. These patients had a 50% pathologic complete response with no tumor found in the resected specimen. All surgical margins were free of disease and there were no operative deaths. This concurrent combined modality therapy is feasible with the major toxicities being leukopenia, nausea, and vomiting. With an overall median follow-up of 15 months, 36% of the patients remain alive. Overall local control is 71%. Actuarial observed 2 yr. survival is 33% and the median survival is 15 months. Histologic complete response appears to be an early indicator of the efficacy of this treatment regime. With 83% of the resected pathologic complete responders alive without evidence of disease, this preoperative combined modality therapy offers an appealing approach.
Nonreciprocal Remanence Phase Shifters in Rectangular Waveguide

Three types of nonreciprocal remanent phase shifters in rectangular waveguide are described which are approximated by a simple model consisting of twin ferrite slabs symmetrically placed in rectangular waveguide and separated by a dielectric rib. The model has been analyzed with the assumption that a fundamental TE mode wave propagates in the structure. Simultaneous solution of Maxwell's equations in the three regions of dielectric, ferrite, and air within the waveguide enables the characteristic equation to be formed. The characteristics of the model have been obtained with the aid of a computer as a function of dimensions, dielectric and magnetic constants, frequency, and power. The theoretical results are compared with experimental data obtained on a double toroid structure. Correction factors applied to the experimental data, which are necessary to account for differences between the practical structure and the ideal model, are discussed.
Exploring Agreement on Appropriate Responses to Domestic Violence and Sexual Trauma Across Victim Advocates, Mental Health Service Providers, and Substance Abuse Treatment Providers

Research suggests that survivors of domestic violence and sexual assault are more at risk than the general population for substance abuse and/or mental health disorders (Kendler et al., 2000). Additionally, research suggests that survivors of both crimes are at risk to be “multiply diagnosed-have” a history of victimization, a mental health diagnosis, and abuse of alcohol and drugs (Steele & Rechberger, 2002). While advocates have called for a change in the treatment of trauma survivors to treat their multiple needs, the availability of collaborative care between victim advocates and behavioral health professionals remains questionable. Using survey data collected from victim advocates, mental health service providers, and substance abuse treatment providers, this study assesses the extent to which providers of different backgrounds agree on how to effectively and appropriately serve domestic violence and sexual assault survivors-the first step in achieving the goal of holistic care.
Implementation and Evaluation of a Student-Centered Learning Unit: A Case Study

The purpose of this case study was to explore the issues involved in implementing a technology-enhanced student-centered unit in order to provide recommendations to improve and enhance these types of learning activities. Specifically, the study examined problems students encountered in completing the unit activities, problems the teacher encountered in facilitating the delivery of the unit to her students, and strategies to improve and enhance these types of learning activities. One teacher and the 21 students in her intact United States history class participated in the study. The central unit problem required students to determine the strategies that should be pursued in 1968 to continue the struggle for a more just, equal United States society. Students worked in teams to gather data from an electronic database of primary- and secondary-source materials, and use the data to develop solutions to the unit problem. Results of this study suggest that a variety of factors impact the success or failure of student-centered activities, including student orientation to the unit problem, student collaboration, teacher management strategies, and student accountability mechanisms. These results also provide insight into how the design of these types of activities can be improved. Perhaps the most important considerations that need additional attention are the additional aids required by teachers as they struggle to implement these types of activities in their classrooms.
Exploring the design space of programmable regular expression matching accelerators

State-of-the-art regular expression (regex) accelerators combine parallel programmable state machines with cascaded, wide-issue instruction processors to improve the storage efficiency and the processing rates, while preserving the programmability. The pattern-matching engine (PME) included on the IBM PowerEN(TM) (Edge-of-Network) processor is one such design, and can be used as an architectural template for a broad design-space exploration. The regex compiler is a key component of such an exploration, involving sophisticated transformations to map large sets of complex regexs to the memory contents and the configuration registers of the accelerator hardware. The design space is explored by varying the main microarchitectural parameters, including the memory size, the number of parallel state machines, and the parameters of the instruction processor. While the design-space exploration confirms the main architectural choices of the PME, it also shows that further optimization is possible by eliminating the bottlenecks in the instruction dispatch mechanisms, which results in an up to 50% reduction in the storage requirements. The design-space exploration utilizes a parameterizable and synthesizable hardware model to evaluate the effects the microarchitectural choices have on the chip area and operating frequency. The synthesis results demonstrate the scalability of the optimization chosen and the need to incorporate these choices into future regex accelerator architectures.
Characterization of murine autoimmune myocarditis induced by self and foreign cardiac myosin

Previously we showed that autoimmune myocarditis could be induced in mice by immunization with purified murine cardiac myosin (MCM). In this study, we found that identical disease could also be induced in genetically susceptible mice by immunization with porcine cardiac myosin (PCM). The cardiac lesions induced by both antigens were characterized by extensive infiltration of the myocardium accompanied by myocyte necrosis. A novel finding was the presence of multinucleated giant cells and eosinophils in the cardiac infiltrates, in addition to a mixture of mononuclear cells and polymorphonuclear cells described previously. Immunohistochemical staining demonstrated that the mononuclear cells consisted predominantly of macrophages, CD4+ T cells and, to a lesser extent, CD8+ T cells and B cells. In addition, increased cardiac expression of adhesion molecules E-selectin, vascular cell adhesion molecule-l (VCAM-1) and intercellular cell adhesion molecule-1 (ICAM-1) were demonstrated in mice that developed myocar...
Halogens in chondrites

Abstract Cl, Br and I contents in samples of the several classes of chondrites have been simultaneously measured by activation analysis. Auxiliary information derived from this work confirms U and Te concentrations and I/Te ratios reported in the literature. For the ordinary (bronzite and hypersthene), pigeonite, enstatite and carbonaceous chondrites the respective Cl contents are 4–90, 120, 516 and 280 ppm; the Br contents are 0·05–0·2, 2·0, 1·5–6·5 and 2·0–11·0 ppm and the I contents are 0·05–0·08, 0·16, 0·07–0·47 and 0·23–1·21 ppm. Cl and Br are positively correlated; most chondrites fall on correlation lines with Cl/Br weight ratios between 20 and 100. Br and I exhibit a simple correlation; most meteorites fall near a line with a Br/I weight ratio of about 1. Leaching experiments yielded results that supported these interhalogen relations, and also gave the degree of water solubility of the halogens: Cl Abundances derived from the data support current thinking that the Type I carbonaceous chondrites have best retained a primordial complement of solar system matter. The astrophysical and meteoritic abundances of chlorine based on oxygen agree reasonably well, 22 vs. ~9 atom Cl 10 4 atom 0; whereas the abundance based on Si differ greatly, 1·5 × 105 vs. 2800 atom Cl 10 6 atom Si.
A model of crystal precipitation

Abstract We study a model of crystal precipitation. The mathematical formulation reduces to studying one conservation law in one space-variable, ∂n(x, t) ∂t + ∂(n(x, t)G)/∂x = 0 , where G is a nonlinear and non-local function of the unknown function n; further, the behavior of G changes drastically along a curve x = x ∗ (t) which depends on n. Results on global existence, uniqueness, and asymptotic behavior (as t → ∞) are established.
Comparing the Effects of Treatment on Female Juvenile Gang and Non-Gang Members

Abstract Most research indicates that males comprise the greatest proportion of gang members. Since the 1990s, however, there has been an increasing interest in female gangs and gang members. The current study builds on this research interest by examining differences between female gang members and non-gang members who participated in a juvenile probation program designed to identify and intervene with youth considered to be high risk for subsequent criminal and delinquent activity. The results of a logistic regression analysis revealed that two factors significantly influenced a female offender's likelihood of being rearrested: she did not complete the program, and she did not live with her natural parent(s). We conclude that the significant results do support findings from previous research in this area; we also discuss possible explanations as to why other factors were not significantly related to rearrests.
Masked-backlighter technique used to simultaneously image x-ray absorption and x-ray emission from an inertial confinement fusion plasmaa)

A method to simultaneously image both the absorption and the self-emission of an imploding inertial confinement fusion plasma has been demonstrated on the OMEGA Laser System. The technique involves the use of a high-Z backlighter, half of which is covered with a low-Z material, and a high-speed x-ray framing camera aligned to capture images backlit by this masked backlighter. Two strips of the four-strip framing camera record images backlit by the high-Z portion of the backlighter, while the other two strips record images aligned with the low-Z portion of the backlighter. The emission from the low-Z material is effectively eliminated by a high-Z filter positioned in front of the framing camera, limiting the detected backlighter emission to that of the principal emission line of the high-Z material. As a result, half of the images are of self-emission from the plasma and the other half are of self-emission plus the backlighter. The advantage of this technique is that the self-emission simultaneous with backlighter absorption is independently measured from a nearby direction. The absorption occurs only in the high-Z backlit frames and is either spatially separated from the emission or the self-emission is suppressed by filtering, or by using a backlighter much brighter than the self-emission, or by subtraction. The masked-backlighter technique has been used on the OMEGA Laser System to simultaneously measure the emission profiles and the absorption profiles of polar-driven implosions.
A 3MHz spoke gyroscope with wide bandwidth and large dynamic range

This paper reports on the design and characterization of a high-frequency silicon bulk acoustic wave (BAW) spoke gyroscope operating in air. The gyroscope described here operates at 3.12MHz in a near mode-matched condition (without tuning) and has a −1dB bandwidth of ∼1.5kHz. The device has a linear full-scale range in excess of 30,000°/sec with a sensitivity of 15.0µV/°/sec using a 10V DC polarization voltage. The wide bandwidth and large dynamic range of this device are beneficial for applications requiring rapid motion sensing.
Altering protein surface charge with chemical modification modulates protein-gold nanoparticle aggregation

Gold nanoparticles (AuNP) can interact with a wide range of molecules including proteins. Whereas significant attention has focused on modifying the nanoparticle surface to regulate protein–AuNP assembly or influence the formation of the protein “corona,” modification of the protein surface as a mechanism to modulate protein–AuNP interaction has been less explored. Here, we examine this possibility utilizing three small globular proteins—lysozyme with high isoelectric point (pI) and established interactions with AuNP; α-lactalbumin with similar tertiary fold to lysozyme but low pI; and myoglobin with a different globular fold and an intermediate pI. We first chemically modified these proteins to alter their charged surface functionalities, and thereby shift protein pI, and then applied multiple methods to assess protein–AuNP assembly. At pH values lower than the anticipated pI of the modified protein, AuNP exposure elicits changes in the optical absorbance of the protein–NP solutions and other properties due to aggregate formation. Above the expected pI, however, protein–AuNP interaction is minimal, and both components remain isolated, presumably because both species are negatively charged. These data demonstrate that protein modification provides a powerful tool for modulating whether nanoparticle–protein interactions result in material aggregation. The results also underscore that naturally occurring protein modifications found in vivo may be critical in defining nanoparticle–protein corona compositions.
X-ray absorption fine structure of systems in the anharmonic limit

A new approach to the analysis of x-ray absorption fine structure (XAFS) data is presented. It is based on the use of radial distribution functions directly calculated from a single-particle ion hamiltonian containing model potentials. The starting point of this approach is the statistical average of the XAFS for an atomic pair. This average can be computed using a radial distribution function (RDF), which can be expressed in terms of the eigenvalues and wavefunctions associated with the model potential. The pair potential describing the ionic motion is then expressed in terms of parameters that are determined by fitting this statistical average to the experimental XAFS spectrum. This approach allows the use of XAFS as a tool for mapping near-neighbor interatomic potentials, and allows the treatment of systems which exhibit strongly anharmonic potentials which can not be treated by perturbative methods. Using this method we have analyzed the high temperature behavior of the oxygen contributions to the Fe K-edge XAFS in the ferrosilicate minerals andradite (Ca3Fe2Si3O12) and magnesiowustite (Mg0.9Fe0.1O). Using a temperature dependent anharmonic correction derived from these model compounds, we have found evidence for a local structural change in the Fe-O coordination environment upon melting of the geologically important mineral fayalite (Fe2SiO4). We have also employed this method to the study of the axial oxygen contributions to the polarized Cu K-edge XAFS on orientated samples of YBa2Cu3O7 and related compounds. From this study we find evidence for an axial oxygen-centered lattice distortion accompanying the superconducting phase transition and a correlation between this distortion and Tc. The relation of the observed lattice distortion to mechanisms of superconductivity is discussed.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A quantitative method for assessing the extent of experimental gastric erosions and ulcers.

Abstract Evaluation of acute gastric erosions and ulcers induced by chemicals such as ethanol or aspirin is difficult because these lesions are predominantly multiple and irregularly shaped. A commercially available, relatively inexpensive microprocessor-linked planimeter (Micro-Plan II) with a stereomicroscope was used to measure the area of gastric mucosa damaged following intragastric administration of various doses of ethanol or aspirin. An enlarged image of rat glandular stomach was projected from the stereomicroscope onto a planimeter on which the perimeter of the entire glandular stomach and each lesion was traced with an electronic cursor. An attached printer recorded the area of stomach assessed, the number of lesions, the surface area of each lesion and the total area of mucosal damage. The technique was compared with semiquantitative methods used previously to assess experimentally induced gastric mucosal damage. The quantitative morphometric method was sufficiently sensitive to demonstrate a dose-response effect of ethanol and aspirin. The stereomicroscope-planimeter combination provides a sensitive method to quantitate either a few small, or numerous large, regularly or irregularly shaped hemorrhagic and nonheemorrhagic gastric mucosal lesions.
Optically and electrically addressed carbon nanofiber electrode arrays for intracellular interfacing

Progress in the application of vertically-aligned carbon nanofibers (VACNF) as parallel subcellular and molecular-scale probes for biological manipulation and monitoring is reported. VACNFs possess many attributes that make them very attractive for implementation as functional, nanoscale features of microfabricated devices. For example, they can be synthesized at precise locations upon a substrate, can be grown many microns long, and feature sharp, nano-dimensioned tips. This, and their needlelike, vertical orientation upon a substrate, makes them particularly attractive as multielement cellular scale probes or as a parallel embodiment of traditional single-point microinjection or microelectrophysiological systems. We will overview our progress with fabricating and characterizing several embodiments of VACNF cell probing systems, which all feature arrays of nanoscale electrochemically-active probing regions at the tips of individually electrically-addressed nanofiber elements. We also overview our techniques of integrating these probing structures with intact cells and how these structures may be used on a massively parallel basis for measurement and control around and within viable cells.
A case-controlled multicenter study of vasovagal reactions in blood donors: influence of sex, age, donation status, weight, blood pressure, and pulse.

BACKGROUND: Vasovagal reactions occur in a small, but significant number of blood donors. These reactions may decrease return donation and disrupt blood collection activities. The purpose of this study was to define the contributory role of sex, age, weight, blood pressure, and pulse in vasovagal reactions with syncope in blood donors. STUDY DESIGN AND METHODS: A retrospective case-control study involved 1890 blood donors with syncope from three large United States blood centers during 1994 and 1995. Case controls and random population controls were used in a logistic regression analysis to determine the significance of individual variables to syncopal reactions. RESULTS: Female donors, young donors, first-time donors, low-weight donors, and donors with low predonation blood pressure had higher absolute donation reaction rates than other donors. When each variable was adjusted for other variables by regression analysis, age, weight, and donation status (first-time or repeat donor) were significant (p<0.0001), and sex, predonation blood pressure, and predonation pulse were not. The most important variables, in descending order, were age, weight, and donation status (first-time or repeat donor). CONCLUSIONS: Donation-related vasovagal syncopal reactions are a multifactorial process determined largely by age, weight, and first-time donor status.
Prospective comparison of endoscopy patient satisfaction surveys: e-mail versus standard mail versus telephone.

Prospective comparison of endoscopy patient satisfaction surveys: e-mail versus standard mail versus telephone
Solution studies of recombinant human stromal-cell-derived factor-1.

Abstract Stromal-cell-derived factor-1 (SDF-1α) is an 8-kDa chemokine that is constitutively expressed in bone-marrow-derived stromal cells and has been identified as a ligand for the CXCR4 receptor. We produced the chemokine recombinantly as methionine-SDF-1α in Escherichia coli without the leader peptide sequence. The protein was denatured, refolded, and further purified by reversed-phase HPLC. SDF-1α was shown to be >95% pure as judged by SDS-PAGE. The final yield of purified and refolded SDF-1α was 1–2 mg per gram of wet cell paste. The refolded protein is a ligand for the CXCR4 receptor and has been used to block HIV-mediated cell fusion and downmodulates the CXCR4 receptor. Our ability to purify hundreds of milligrams of refolded protein allowed us to conduct detailed studies of the biophysical properties of the protein. We have used a combination of biophysical techniques to study the solution properties of SDF-1α. The average mass of SDF-1α, as determined by static light scattering, gave us the first indications that the chemokine may self-associate. Further investigation with sedimentation velocity ultracentrifugation confirmed the existence of two species. The measured s20, W values defined two masses corresponding to monomer and dimer. Finally, sedimentation equilibrium ultracentrifugation and dynamic light scattering yielded a composite value of 150 ± 30 μM for the dimerization constant. We conclude that SDF-1α exists in a monomer-dimer equilibrium.
Three‐dimensional variations in Love and Rayleigh wave azimuthal anisotropy for the upper 800 km of the mantle

We present a new mantle model (YB14SHani) of azimuthal anisotropy for horizontally polarized shear waves (SH) in parallel with our previously published vertically polarized shear wave (SV) anisotropy model (YB13SVani). YB14SHani was obtained from higher mode Love wave phase velocity maps with sensitivity to anisotropy down to ~1200 km depth. SH anisotropy is present down to the mantle transition zone (MTZ) with an average amplitude of ~2% in the upper 250 km and ~1% in the MTZ, consistent with YB13SVani. Changes in SV and SH anisotropy were found at the top of the MTZ where olivine transforms into wadsleyite, which might indicate that MTZ anisotropy is due to the lattice-preferred orientation of anisotropic material. Beneath oceanic plates, SV fast axes become subparallel to the absolute plate motion (APM) at a depth that marks the location of a thermally controlled lithosphere-asthenosphere boundary (LAB). In contrast, SH anisotropy does not systematically depend on ocean age. Moreover, while upper mantle SV anisotropy is anomalously high in the middle of the Pacific, as seen in radial anisotropy models, SH anisotropy amplitude remains close to the average for other oceans. Based on the depth at which SV fast axes and the APM direction begin to align, we also found that the average thickness of cratonic roots is ~ 250 km, consistent with Yuan and Romanowicz (2010) for North America. Here we add new constraints on the nature of the cratonic LAB and show that it is characterized by changes in both SV and SH anisotropy.
Relationship between neuronal migration and cell-substratum adhesion: laminin and merosin promote olfactory neuronal migration but are anti-adhesive.

Regulation by the extracellular matrix (ECM) of migration, motility, and adhesion of olfactory neurons and their precursors was studied in vitro. Neuronal cells of the embryonic olfactory epithelium (OE), which undergo extensive migration in the central nervous system during normal development, were shown to be highly migratory in culture as well. Migration of OE neuronal cells was strongly dependent on substratum-bound ECM molecules, being specifically stimulated and guided by laminin (or the laminin-related molecule merosin) in preference to fibronectin, type I collagen, or type IV collagen. Motility of OE neuronal cells, examined by time-lapse video microscopy, was high on laminin-containing substrata, but negligible on fibronectin substrata. Quantitative assays of adhesion of OE neuronal cells to substrata treated with different ECM molecules demonstrated no correlation, either positive or negative, between the migratory preferences of cells and the strength of cell-substratum adhesion. Moreover, measurements of cell adhesion to substrata containing combinations of ECM proteins revealed that laminin and merosin are anti-adhesive for OE neuronal cells, i.e., cause these cells to adhere poorly to substrata that would otherwise be strongly adhesive. The evidence suggests that the anti-adhesive effect of laminin is not the result of interactions between laminin and other ECM molecules, but rather an effect of laminin on cells, which alters the way in which cells adhere. Consistent with this view, laminin was found to interfere strongly with the formation of focal contacts by OE neuronal cells.
Mitochondrial plasmids of Neurospora: integration into mitochondrial DNA and evidence for reverse transcription in mitochondria.

Abstract The Mauriceville (3.6 kb) and Varkud (3.8 kb) mitochondrial plasmids of Neurospora are closely related, closed circular DNAs whose nucleotide sequences and genetic organization suggest relationships to mitochondrial introns and retrotransposons. Here we isolated mutants whose growth is impaired as a result of malevolent behavior of these plasmids. All 12 mutants contain variant plasmids that are suppressive relative to mtDNA, and ten also contain defective mtDNAs. All the suppressive plasmids contain small insertions, generally including a mitochondrial tRNA sequence, at or near the major 5′ RNA start site. The structure of the suppressive plasmids suggests that they were generated via an RNA intermediate and a reverse transcription step. At least three of the mutants contain defective mtDNAs into which mitochondrial plasmid sequences have integrated. Sequences at the plasmid-mtDNA junctions are also consistent with integration via an RNA intermediate.
Look-ahead architecture adaptation to reduce processor power consumption

An effective approach to reducing processor power consumption is to adaptively activate and deactivate hardware resources. The authors propose a look-ahead scheme that adjusts the processor issue rate triggered by main-memory accesses. This architecture-independent technique is particularly effective for memory-intensive applications. Combined with an existing technique based on IPC values, it also reduces power consumption for computation-intensive applications.
Design and Use of Computer Tools for Interactive Mathematical Activity (TIMA)

Our guiding principle when designing the TIMA was to create computer tools that we could use to achieve our goals when teaching children. The design of the TIMA took place in the context of a constructivist teaching experiment with 12 children that extended over a three-year period. Three different TIMA were designed and used in the teaching experiment: Toys, Sticks, and Bars. These tools were designed to provide children contexts in which they could enact their mathematical operations of unitizing, uniting, fragmenting, segmenting, partitioning, disembeding, iterating and measuring. As such, they are very different from the drill and practice or tutorial software that are prevalent in many elementary schools. We provide examples of how the TIMA were used by children to engage in cognitive play and, through interactions with a teacher/researcher and other children, transform that play into independent mathematical activity with a playful orientation. The role of the teacher in provoking perturbations that...
Initial linkage and subsequent retention in HIV care for a newly diagnosed HIV-infected cohort in Denver, Colorado.

This is a retrospective cohort study of 352 newly diagnosed HIV-infected individuals in Denver, from 2005 to 2007. Utilizing data from 3 health care systems, 2 clinical trials units, and statewide Colorado HIV laboratory reporting databases, we tracked initial linkage to HIV care, retention in care, loss to follow-up, and transitions between HIV care providers. After more than 2.6 years of follow-up, 256 (73%) individuals linked to HIV care within 180 days. Of the 301 individuals who eventually linked to care, 168 (56%) had at least one 180-day gap in care, while 49 (16%) had a 360-day gap. Transitions in care were common, with 131 (37%) individuals accessing care from 2 different providers and 15% having evidence of living outside of Colorado. In this newly diagnosed HIV-infected cohort, linkage to care was slow and long-term retention in care was poor. Transitions between HIV care providers were common and may impair engagement in care over time. Out-of-state migration was frequent and may cause an unde...
Physical Basis behind Achondroplasia, the Most Common Form of Human Dwarfism

Fibroblast growth factor receptor 3 (FGFR3) is a receptor tyrosine kinase that plays an important role in long bone development. The G380R mutation in FGFR3 transmembrane domain is known as the genetic cause for achondroplasia, the most common form of human dwarfism. Despite many studies, there is no consensus about the exact mechanism underlying the pathology. To gain further understanding into the physical basis behind the disorder, here we measure the activation of wild-type and mutant FGFR3 in mammalian cells using Western blots, and we analyze the activation within the frame of a physical-chemical model describing dimerization, ligand binding, and phosphorylation probabilities within the dimers. The data analysis presented here suggests that the mutation does not increase FGFR3 dimerization, as proposed previously. Instead, FGFR3 activity in achondroplasia is increased due to increased probability for phosphorylation of the unliganded mutant dimers. This finding has implications for the design of targeted molecular treatments for achondroplasia.
Mechanical properties of spinal nerve roots subjected to tension at different strain rates

An understanding of the biomechanical and physiological properties of spinal nerve roots, particularly in response to tension, is critical in understanding the pathomechanisms of pain and nerve root injury and subsequent management of related injuries. Biomechanical properties of dorsal nerve roots at the lumbar and sacral levels were evaluated at various strain rates. Nerve roots were stretched at two different rates, 0.01 mm/s (Group A, quasistatic) and 15 mm/s (Group B, dynamic). Load, displacement and digital video data were obtained as the nerve roots were stretched until failure. Maximum stress, strain at maximum stress and modulus of elasticity (E) were calculated from the load-displacement measurements. Comparison of mechanical properties and failure patterns of nerve roots at two different rates revealed significant differences. Maximum load, maximum stress and E values of 5.7+/-2.7 gm, 257.9+/-111.3 kPa and 1.3+/-0.8 MPa were observed for Group A and 13.9+/-7.5 gm, 624.9+/-306.8 kPa and 2.9+/-1.5 MPa were observed for Group B, respectively. Higher maximum load, maximum stress and E values occurred at the dynamic stretch rate as compared to the quasistatic stretch rate, illustrating the strain-rate dependency of spinal nerve roots. No differences were observed in the strain values. Differences in mechanical behavior of nerve roots were also observed among the four root levels (L4-S1). A significant interaction effect was observed between nerve root diameter and stretch rates. Overall, results from the present study demonstrate viscoelastic material properties of spinal nerve roots and provide better insight on the tensile properties of nerve roots at different strain rates.
Non-Invasive Real-Time Study of Cell Adhesion using Dissipation Monitoring of the QCM-D

Cell adhesion is an essential biological process for cell survival, differentiation, and migration. There are two types of cell adhesion to the extracellular matrix (ECM) and adhesion to adjacent cells. Cell-substrate adhesion is mediated through a class of receptors known as integrins. There receptors simultaneously connect the ECM on the outside to the actin filaments on the inside of the cells. Another important cell adhesion is cell-cell adhesion; it is an essential component of epithelial morphology, cellular communication and function. Epithelial cells adhere tightly to their neighbors through adhesive structures and these structures are connected to intermediate filaments microfilaments. This association with the cytoskeletal network is necessary for stable cell-cell adhesion and for the communication of the changes in neighboring cells. There are many methods that can be used to measure the changes in cell adhesion, but each has its disadvantages. Many of these methods are based on end-point detection which don't allow real-time detection or are based on the introduction of foreign objects which can affect the response of cells. We have developed a non-invasive real time method using the quartz crystal microbalance with dissipation monitoring (QCM-D) to quantitatively monitor such cellular processes using the dissipation factor ΔD. Previously, we've successfully tracked real time changes in cellular adhesion due to induction of the EGFR pathway using the QCM-D. The QCM-D technique can be a useful application in studying other cellular process such as cell signaling and trafficking and can potentially be a useful in vitro method for drug and biomarker screenings. Here we will take a look at pathways that contribute to changes in cell adhesion through cell-ECM adhesion and cell-cell adhesion.
SU-E-T-102: Evaluation of the Characteristics of TLD LiF:Mg.Ti-100 Powder: A Measure of Consistency between Multiple Batches of Powder.

Purpose: Analyze the characteristics of TLD LiF‐100 powder between multiple LiF crystal batches. Methods: The RPC used TLD LiF‐100 encapsulated powder to verify the output for photon and electron beams for 4 to 23 MV X‐ray beams and 6 to 23 MeV electron beams, respectively, from the past 15 years. During that time period, the RPC commissioned more than 15 batches of TLDpowder. Commissioning of each batch of powder encompassed determining the system sensitivity (dose response), linearity, energy and fading characteristics of each batch of powder to determine the correction factors for the calculation of dose. The system sensitivity is the signal/mg per unit known dose of 60Co for each reading session. Other correction factors account for the loss of signal (fading) between the irradiation and read dates, supralinearity of the dose response and energy differences as compared to the 60Co irradiated standards. Results: More than 15 batches of TLD were commissioned to determine correction factors for the calculation of dose. The correction for fading, a characteristic of the LiF crystal, varied by ±1% between the multiple batches. The linearity correction, between 25 and 600cGy, normalized to 300cGy, showed a maximum variation of ±3% between batches. The energy correction factors, as defined for the RPC beam output audit system varied within ±1.7% (one std dev.) for the 15 batches. The system sensitivity is highly dependent on the LiF crystal grown for each batch, specific TLD reader and reading session conditions. The system sensitivity, while keeping the readers and reading sessions constant, varied by as much as 20% between batches. Conclusions: Each batch of LiF‐100 TLDpowder showed variability in their powder characteristics such that calculation of dose accurately, with minimal uncertainty, requires a new commissioning. Work supported by PHS CA010953 awarded by NCI, DHHS
Course of compulsive hoarding and its relationship to life events.

Background: Compulsive hoarding is a common and debilitating, yet poorly understood, condition characterized by excessive acquisition of and failure to discard a large number of objects, resulting in cluttered and often hazardous living conditions. The aim of this study was to examine the onset and course of compulsive hoarding, and the relationships between stressful or traumatic life events and course of illness. Methods: Seven hundred fifty-one adults with self-reported hoarding symptoms completed an online survey regarding the severity of hoarding behavior over the lifespan and the incidence of stressful or traumatic life events. Results: Median age of onset was between 11 and 15 years, with most respondents reporting symptom onset before age 20. Late-onset (e.g., after age 40) hoarding was rare. Most respondents described a chronic course of illness, with a significant minority describing an increasing or relapsing/remitting course. Stressful and traumatic events were common in this sample; changes in relationships and interpersonal violence were disproportionately associated temporally with periods of symptom onset or exacerbation. Conclusions: These results highlight the chronic nature of compulsive hoarding, its associated public health burden, and the potential impact of life stressors on symptom development. Directions for further research are discussed. Depression and Anxiety, 2010. © 2010 Wiley-Liss, Inc.