cssi/SciSciGPT-SciSciNet huggingface dataset:
Kinetics of OH Chemiluminescence in the Presence of Hydrocarbons

Shock-tube experiments and chemical kinetics simulations have been used to optimize a kinetics model for the electronically excited OH radical (OH*) in a hydrocarbon environment at high temperatures (1420 < T < 2335 K) and at pressures between 0.8 and 3.0 atm. Ultraviolet emission near 307 nm was recorded from the shock-tube sidewall, and absolute concentrations were used to obtain a rate expression for the elementary reaction primarily responsible for formation of OH*, i.e. CH + O2 ⇆ OH* + CO. Absolute concentrations were deduced from a previously established calibration employing the relatively well-known kinetics of the H2/O2 system. To isolate the phenomena of interest, experiments were performed with mixtures of CH4 and H2 with O2, highly diluted in Argon, and elementary reactions accounting for formation and quenching of OH* were added to the GRI-Mech 3.0 detailed mechanism. Sensitivity analyses indicate that the maximum OH* concentration is most strongly sensitive to the formation path through CH + O2 so that this reaction rate could be found by varying its coefficient to match the experimental concentration. In this manner, the rate coefficient was found to be k1 = (4 ± 3)×10 cm mol s, independent of temperature and pressure. Uncertainties in this rate due to the calibration reaction and to scatter in the data are considered, and results are compared to values previously available in the literature. The end result is an optimized diagnostic accurate over a broad range of conditions encountered in combustion and propulsion applications.
Vacancy ordering at heterovalent interfaces

Abstract Atomic structures of three Ga 2 Se 3 epilayers grown on GaAs(100) or ZnSe(100) epilayers by molecular beam epitaxy were studied by transmission electron microscopy. A new vacancy ordered structure was found in the heteroepitaxial interface regions of Ga 2 Se 3 epilayers. The ordered structure is described as an alternate stacking of two types of Ga planes in the growth direction. One half of the sites are vacancies in one type of Ga plane, while the other type of Ga plane is fully occupied by Ga atoms. Comparison of three Ga 2 Se 3 epilayers indicates a strong influence of surface chemistry of substrate epilayers on the formation of the vacancy ordering. A highly developed two-dimensional ordering has occured in the epilayer grown on a GaAs(100) surface with (4 × 3) rereconstructions.
Control-flow analysis of dynamic languages via pointer analysis

We demonstrate how to map a control-flow analysis for a higher-order language (dynamic languages are typically higher-order) into a pointer analysis for a first-order language, such as C. This allows us to use existing pointer analysis tools to perform a control-flow analysis, exploiting their technical advancements and the engineering effort that went into developing them. We compare the results of two recent parallel pointer analysis tools with a parallel control-flow analysis tool. While it has been known that a control-flow analysis of higher-order languages and a pointer analysis of first-order languages are very similar, we demonstrate that these two analyses are actually more similar than previously thought. We present the first mapping between a high-order control-flow analysis and a pointer analysis.
Thermospray liquid chromatographic—mass spectrometric analysis of anti-AIDS nucleosides: quantification of 2',3'-dideoxycytidine in plasma samples

Thermospray liquid chromatography-mass spectrometry was investigated as a method for quantification of 2',3'-dideoxycytidine (DDC) from human plasma. A stable isotope analog of DDC ([15N2,2H2]DDC) was used as an internal standard. Selected ion monitoring of the protonated molecular ions for DDC and the internal standard was used to record mass chromatograms. The areas of the peaks in the mass chromatograms were used for quantification. The detection limit of DDC in this assay was 50 pg on-column. The calibration curve was linear over the desired range, 0.25-20 ng/ml. The major advantages of this assay over others are: no derivatization, high sensitivity, high specificity and short assay time.
Molecular mechanisms of novel therapeutic approaches for multiple myeloma.

Multiple myeloma remains largely incurable despite conventional and high-dose therapies, and so novel biologically based treatment approaches are urgently required. Recent studies have characterized the molecular mechanisms by which multiple myeloma cell–host bone-marrow interactions regulate tumour cell growth, survival and migration in the bone-marrow microenvironment. These studies have not only enhanced our understanding of disease pathogenesis, but have also provided the framework for a new treatment model that targets the multiple myeloma cell in its bone-marrow microenvironment to overcome drug resistance and improve patient outcome.
Four forms of tyrosine hydroxylase are present in human adrenal medulla.

: Alternative splicing can result in up to four forms of human tyrosine hydroxylase (HTH) mRNA (mRNAHTH). In the adrenal gland, a major site of catecholamine biosynthesis, the presence of all four mRNAHTH forms is controversial. In the present study, postmortem human adrenal medullary tissue was analyzed for the presence of multiple forms of HTH protein by blot immunolabeling. Electrophoretic transfers were developed with affinity-purified rabbit anti-HTH antibodies raised against peptides that reproduced the unique amino acid sequences predicted by the four mRNAHTH forms. All four of the predicted HTH protein forms were present in the adrenal glands from a diverse sample population.
Nonspecific suppressor cell function in atopic subjects.

Abstract The status of concanavalin A (Con A)-nonspecific suppressor cell function and histamine-receptor-carrying mononuclear cells in 19 allergic and 27 nonallergic individuals was investigated. No differences were detected between the two groups with respect to suppression by Con A-activated suppressor cells of polyvalent IgG biosynthesis, IgG secretion, or mitogen-induced proliferative responses. Histamine-receptor-carrying cells of the allergic subjects were numerically equal to those of the nonallergic subjects. Mononuclear cells from the allergic group, however, required a higher dose of histamine than did those for the nonallergic group to induce suppression in vitro (p −4 M histamine and p −3 M histamine). Plasma from the allergic group contained higher levels of histamine activity (p
Entropy and superposition principle

Abstract Given a faithful normal state ϕ of a von Neumann algebra M , entropy and relative entropy for normal states of M are defined by Radon-Nikodyn derivatives of normal states with respect to ϕ. Most properties of entropy and relative entropy in finite quantum systems are shown to hold. It is also shown that the finiteness of relative entropy is related to the facial superposition principle in quantum theory [5].
Damage to Epithelial Basement Membrane by Thermokeratoplasty

To determine the effects of thermokeratoplasty (TKP) on the basement membrane complexes of the corneal epithelium, transmission electron microscopy was performed on the corneal buttons of five patients with failed TKP and on two normal corneas and five corneas with keratoconus that were immediately treated by TKP (acute TKP). The consistent findings of thermal dissolution of basement membrane after acute TKP and persistent defects of basement membrane complexes many months after therapeutic thermokeratoplasty were significant. Given the potentially damaging effects of thermokeratoplasty on the epithelial basement membrane, faulty epithelial adhesion should be anticipated after thermokeratoplasty and should be treated aggressively, possibly with careful prophylactic use of bandage hydrophilic contact lenses.
Costs of a predictable switch between simple cognitive tasks following severe closed-head injury

The authors used a predictable, externally cued task-switching paradigm to investigate executive control in a severe closed-head injury (CHI) population. Eighteen individuals with severe CHI and 18 controls switched between classifying whether a digit was odd or even and whether a letter was a consonant or vowel on every 4th trial. The target stimuli appeared in a circle divided into 8 equivalent parts. Presentation of the stimuli rotated clockwise. Participants performed the switching task at both a short (200 ms) and a long (1,000 ms) preparatory interval. Although the participants with CHI exhibited slower response times and greater switch costs, similar to controls, additional preparatory time reduced the switch costs, and the switch costs were limited to the 1st trial in the run. These findings indicate that participants with severe CHI were able to take advantage of time to prepare for the task switch, and the executive control processes involved in the switch costs were completed before the 1st trial of the run ended.
Reduced mortality and moderate alcohol consumption: The phospholipase D-mTOR connection

Many studies have suggested that moderate alcohol consumption reduces mortality. There is also substantial evidence that lifespan is extended with suppression of TOR (target of rapamycin). It was reported recently that rapamycin is able to extend the lifespan of a mammal—implicating the mammalian TOR (mTOR). mTOR has a requirement for the lipid second messenger phosphatidic acid (PA), which is generated by phospholipase D (PLD). Therefore, in principle, suppression of PLD would be similar to treatment with rapamycin. Significantly, PLD utilizes ethanol preferentially over water in the hydrolysis reaction that ordinarily generates PA. In the presence of ethanol, phosphatidyl-ethanol is generated at the expense of PA leading to the suppression of mTOR. This reaction, known as the transphosphatidylation reaction, provides a mechanistic basis for the reduced mortality observed with moderate consumption of alcohol—that being the suppression of mTOR.
Abdominal and pelvic needle aspiration biopsies: can we perform them well when using small needles?

Background: The aim of this study was to compare abdominal fine-needle aspirations (FNAs) performed with large (≥20-gauge) or small (≤21-gauge) needles for diagnostic rate, number of samples required for diagnosis, diagnostic accuracy, and complication rates. Methods: Abdominal and pelvic FNA procedures were retrospectively reviewed. Needle size, imaging guidance used, number of pathology slides created, complications, and cytologic and final diagnoses were obtained by reviewing radiologic, medical, and cytology records. Results: Two hundred ninety procedures were included in the study. Two hundred fifty-seven were performed in patients having only one biopsy during the study interval. Of these, 159 had biopsies using small needles and 98 using large needles. Small needle biopsies had as high a diagnostic rate as did large needle biopsies (97.5% vs. 92.9%, p= 0.11). Small and large needle biopsies showed high diagnostic accuracy (96.1 and 98.9%, respectively; p= 0.27). Incorrect cytologic diagnoses plus nondiagnostic examinations composed 6.3% of biopsies using small needles and 8.2% of biopsies using larger needles (p= 0.62). Complication rates were low. Average number of needle passes tended to be lower when small needles were used. Conclusion: Small needles can be successfully used for abdominal and pelvic FNAs. Small needles require the same or fewer needle passes, have low risk, have the same or improved ability to obtain diagnostic material, and achieve correct diagnoses compared with larger needles.
African Women Scientists and the Politics of Location: The Case of Four Sierra Leonean Women Scientists

This paper examines the attempts of four Sierra Leonean women scientists to restructure their lives and professional careers in the wake of changing political and economic conditions in their nation state. I show how their emotional affinities to their country of origin are still strong and influence their scientific practices and commitments to their country of origin. I argue that as transnational migrants, their experiences are shaped by the intersection of inequalities of gender, race, and nation and changing economic, social, and political processes in their countries of origin and destination. These conditions may constrain but also enable them to compete, challenge, and negotiate new spheres of lived experience. The analysis is framed around discourses on the brain drain, the concept of transnationalism, and feminist research on gender and migration. The study is based on semi-structured interviews, using narratives to illustrate the lived experiences and perspectives of the study participants. Issues addressed include (1) factors leading to migration, (2) experiences of race, gender, and nationality, (3) ways of practicing science, (4) navigation of emotional commitments to country of origin.
Fluctuations in the production of intermediate mass fragments in heavy ion collisions

Abstract We study the the fluctuations in the number of intermediate mass fragments produced in heavy ion collisions. Of particular recent interest are the questions of scaling and reducibility of the probability distribution function of this observable. We show that the observed reducibility is a spurious effect, due to finite-number effects and the correlation between the measured transverse energy and the total charge recovered in the detector, Using only very simple assumptions, we are able to reproduce the observed binomial emission probabilities and their dependencies on the transverse energy, Finally, using the percolation model, we also show that useful information on the mechanism of intermediate mass fragment emission can be extracted from completely reconstructed events.
Automated Sholl analysis of digitized neuronal morphology at multiple scales.

Neuronal morphology plays a significant role in determining how neurons function and communicate1-3. Specifically, it affects the ability of neurons to receive inputs from other cells2 and contributes to the propagation of action potentials4,5. The morphology of the neurites also affects how information is processed. The diversity of dendrite morphologies facilitate local and long range signaling and allow individual neurons or groups of neurons to carry out specialized functions within the neuronal network6,7. Alterations in dendrite morphology, including fragmentation of dendrites and changes in branching patterns, have been observed in a number of disease states, including Alzheimer's disease8, schizophrenia9,10, and mental retardation11. The ability to both understand the factors that shape dendrite morphologies and to identify changes in dendrite morphologies is essential in the understanding of nervous system function and dysfunction. Neurite morphology is often analyzed by Sholl analysis and by counting the number of neurites and the number of branch tips. This analysis is generally applied to dendrites, but it can also be applied to axons. Performing this analysis by hand is both time consuming and inevitably introduces variability due to experimenter bias and inconsistency. The Bonfire program is a semi-automated approach to the analysis of dendrite and axon morphology that builds upon available open-source morphological analysis tools. Our program enables the detection of local changes in dendrite and axon branching behaviors by performing Sholl analysis on subregions of the neuritic arbor. For example, Sholl analysis is performed on both the neuron as a whole as well as on each subset of processes (primary, secondary, terminal, root, etc.) Dendrite and axon patterning is influenced by a number of intracellular and extracellular factors, many acting locally. Thus, the resulting arbor morphology is a result of specific processes acting on specific neurites, making it necessary to perform morphological analysis on a smaller scale in order to observe these local variations12. The Bonfire program requires the use of two open-source analysis tools, the NeuronJ plugin to ImageJ and NeuronStudio. Neurons are traced in ImageJ, and NeuronStudio is used to define the connectivity between neurites. Bonfire contains a number of custom scripts written in MATLAB (MathWorks) that are used to convert the data into the appropriate format for further analysis, check for user errors, and ultimately perform Sholl analysis. Finally, data are exported into Excel for statistical analysis. A flow chart of the Bonfire program is shown in Figure 1.
New developments in the theory of pressure-broadening and pressure-shifting of spectral lines of H2O: The complex Robert-Bonamy formalism

Abstract Calculations of the halfwidth and line shift of water vapor perturbed by N2, O2, CO2, and H2 based on a complex implementation of the formalism of Robert and Bonamy are made. The potentials employ the leading terms of the electrostatic potential, a Lennard -Jones (6–12) atom-atom potential, and the induction and dispersion components of the isotropic potential. The dynamics of the collisions are correct to second order in time. The results are compared with measurements and very good agreement is observed for both halfwidths and line shifts. A new feature in this approach is that the real and imaginary components of the S matrix affect both the halfwidth and the line shift. It is shown here that the imaginary parts of the S matrix strongly affect the calculated halfwidths for some of the systems considered.
Reversal of Dopamine D2 Agonist-Induced Inhibition of Ventral Tegmental Area Neurons by Gq-Linked Neurotransmitters Is Dependent on Protein Kinase C, G Protein-Coupled Receptor Kinase, and Dynamin

Dopaminergic neurons of the ventral tegmental area are important components of brain pathways related to addiction. Prolonged exposure of these neurons to moderate concentrations of dopamine (DA) decreases their sensitivity to inhibition by DA, a process called DA-inhibition reversal (DIR). DIR is mediated by phospholipase C and conventional subtype of protein kinase C (cPKC) through concurrent stimulation of D2 and D1-like DA receptors, or by D2 stimulation concurrent with activation of 5-HT2 or neurotensin receptors. In the present study, we further characterized this phenomenon by use of extracellular recordings in brain slices to examine whether DIR is linked to G protein-coupled receptor kinase-2 (GRK2) or dynamin by assessing DIR in the presence of antagonists of these enzymes. DIR was blocked by β-ARK1 inhibitor, which inhibits GRK2, and by dynasore, which blocks dynamin. Reversal of inhibition by D2 agonist quinpirole was produced by serotonin (50 µM) and by neurotensin (5–10 nM). Serotonin-induced or neurotensin-induced reversal was blocked by β-ARK1 inhibitor, dynasore, or cPKC antagonist 5,6,7,13-tetrahydro-13-methyl-5-oxo-12H-indolo[2,3-a]pyrrolo[3,4c]carbazole-12-propanenitrile (Go6976). This further characterization of DIR indicates that cPKC, GRK2, and dynamin play important roles in the desensitization of D2 receptors. As drugs of abuse produce persistent increases in DA concentration in the ventral tegmental area, reduction of D2 receptor sensitivity as a result of drug abuse may be a critical factor in the processes of addiction.
Ambiguity in antiproton-nucleus potentials from antiprotonic-atom data

We show that the $\overline{\mathrm{p}}$-atomic data for $\overline{\mathrm{p}}$+ $^{12}\mathrm{C}$, $^{16}\mathrm{O}$, S, and $^{89}\mathrm{Y}$ do not yield unique $\overline{\mathrm{p}}$-nucleus potentials. Two families of potentials are found, one with shallow imaginary and deep real parts and one with deep imaginary and shallow real parts. We examine some possible consequences for the n-$\overline{\mathrm{n}}$ oscillation time, for $\overline{\mathrm{p}}$-nuclear bound states, and for $\overline{\mathrm{p}}$-nucleus scattering.
Organoactinide phosphine/phosphite coordination chemistry. Facile hydride-induced dealkoxylation and the formation of actinide phosphinidene complexes

A study of the reaction of the organoactinide hydrides (Cp'/sub 2/MH/sub 2/)/sub 2/ (Cp' = eta/sup 5/-(CH/sub 3/)/sub 5/C/sub 5/, M = Th, U) with trimethyl phosphite is reported. Quantitative transposition of hydride and methoxide ligands occurs to yield the corresponding Cp'/sub 2/M(OCH/sub 3/)/sub 2/ complexes (synthesized independently from Cp'/sub 2/MCl/sub 2/ and NaOCH/sub 3/) and the phosphinidene-bridged methoxy complexes (Cp'/sub 2/M(OCH/sub 3/))/sub 2/PH. The reaction is considerably more rapid for M = U than for M = Th. The new compounds were characterized by elemental analysis, /sup 1/H and /sup 31/P NMR, infrared spectroscopy, magnetic susceptibility, and D/sub 2/O hydrolysis. The molecular structure of (Cp'/sub 2/U(OCH/sub 3/))/sub 2/PH has been determined by single-crystal X-ray diffraction techniques. It crystallizes in the monoclinic space group P2/n with a = 13.926 (3) A, b = 10.765 (3) c = 15.282 (4) A, ..beta.. = 107.63 (2)/sup 0/, and Z = 2. Full-matrix least-squares refinement of the structural parameters for the 24 independent anisotropic non-hydrogen atoms has converged to R/sub 1/ (unweighted, based on F) = 0.041 for 1677 independent absorption-corrected reflections having 2 theta/sub MoK..cap alpha../ 3sigma(I). The (Cp'/sub 2/U(OCH/sub 3/))/sub 2/PH molecule has C/sub 2/more » symmetry, with the ..mu..-PH/sup 2 -/ ligand lying on a crystallographic twofold axis. The coordination geometry about each uranium ion is of the typical pseudotetrahedral Cp'/sub 2/M(X)T type, with U-P = 2.743 (1) A, U-O = 2.046 (14) A, angle U-P-U = 157.7 (2)/sup 0/, and angle U-O-C (methyl) = 178 (1)/sup 0/. Evidence is presented that other > P-OR linkages react in a similar manner.« less
Third-Party Intermediaries and Negotiated Settlements, 1946–2000

Past studies regarding the success and/or failure of conflict management activities have brought about a wide range of results. In this paper we attempt to gain more definitive conclusions about effectiveness by accomplishing two tasks. First, using a basic theoretical framework we identify expectations of efficacy as they relate to differences between states, coalitions, and IGOs. Second, we also examine the utility of different conflict management techniques in an effort to place in greater perspective the effectiveness of mediation, the most utilized technique of third party intermediaries. Using a new dataset on third-party intermediary behavior in militarized disputes from 1946 to 2000, we find that while all conflict managers are useful in assisting belligerents in reaching a negotiated settlement, IGOs are the most effective. Additionally, while mediation is an effective technique to produce settlements, military intermediary actions, such as peacekeeping, are much more useful.
Link between diagnostic X-rays and cancer uncertain☆

Abstract Question Do diagnostic X-rays increase the risk of developing cancer? Study design Epidemiological risk analysis. Main results By age 75, the cumulative risks of cancer resulting from diagnostic X-rays were estimated to be between 0.6% (in the UK and Poland) and 3.2% (Japan). In all other populations the estimated risk was between 0.7% and 1.8%. The UK risk correlates to 700 cases per year including 111 bladder cancers, 107 colon cancers and 61 lung cancers. Authors’ conclusions According to their model, the estimated cumulative risk of cancer caused by diagnostic X-rays varied between countries, however most were fewer than 2%. In Japan the estimated cumulative risk exceeded 3%.
Beyond Polymaxenolide: Cembrane-Africanane Terpenoids from the Hybrid Soft Coral Sinularia maxima × S. polydactyla

The effects of natural hybridization on secondary metabolite production and diversification have only recently been studied in plants and have essentially been overlooked in marine organisms. Chemical investigation of the hybrid soft coral Sinularia maxima × S. polydactyla resulted in the isolation of five new terpenoids, 7E-polymaxenolide (1), 7E-5-epipolymaxenolide (2), and polymaxenolides A−C (3−5), possessing a cembrane-africanane skeleton. Their structures were established by detailed analysis of NMR and MS data. The contentious issue of defining the absolute configuration at the stereogenic centers of the conformationally mobile cembrane macrocyclic ring was addressed by joint application of electronic circular dichroism and X-ray diffraction analyses.
Development of an H2O Atmosphere around Comet Kohoutek (1973f) and its Possible Detection

Although chemically stable 'parent molecules' for the observed radicals in comets, have been suspected for more than thirty years none of them has yet been observed spectroscopically. The newly discovered great comet Kohoutek may provide an excellent opportunity for directly observing a 'parent molecule' (namely, H2O) for the first time. The continuous development of a H2O atmosphere around the nucleus as the comet approaches the sun is discussed together with the detection of this atmosphere, using ground-based instruments and instruments carried in aircraft, balloons, and rockets.
Relevance of GASB No. 34 to Financial Reporting by Municipal Governments

SYNOPSIS: The Governmental Accounting Standards Board issued Statement No. 34, creating a new accrual-based financial reporting model. This study examines whether information from this model is associated with the default risk (a proxy for fiscal distress) of municipal governments and whether this information is incremental to that provided by the fund-based, modified-accrual reporting model. Ordered logistic regressions are used to analyze financial data from 2005 for a sample of 409 municipalities that participated in the Government Finance Officers Association award program. This study extends the work of Plummer et al. (2007) to municipal governments. In addition to the financial position indicator variable (total net assets/total revenues) examined by Plummer et al. (2007), this study provides evidence of the relevance of three other financial indicators (change in net assets/total net assets; total liabilities/total assets; and current assets/current liabilities). We also find that these accrual-bas...
A multi-dimensional classification and equity analysis of an urban park system: A novel methodology and case study application

Abstract This study introduces a novel, multidimensional methodology for empirically classifying urban parks according to their physical, land cover, and built features. An equity analysis compares the resulting park types to neighborhood social characteristics, statistically and spatially evaluating who has access to which kind of park. The process can be customized to the built, geographic, and social conditions and public policy goals of other cities, but is here applied to Phoenix, Arizona. The case study application provides a proof of concept, revealing the composition and distribution of various park types and demonstrating the utility and feasibility of the classification procedure and equity analysis. Results reveal five distinct park types in Phoenix – Suburban Amenity Parks, Green Mini Parks, Native Desert Preserves, Green Neighborhood Parks, and Urban Core Parks – each exhibiting a unique mix of physical, spatial, land cover, and built characteristics. The equity analysis highlights priority areas for park improvements, potential equity concerns, and phenomena for future research. A discussion section evaluates the results in light of previous research and suggests how findings can inform sustainable and just urban park policy, planning, and management.
Interface stress distributions in transversely loaded continuous fiber composites: parallel computation in multi-fiber RVEs using the boundary element method

Abstract We present the results of a computational investigation on the effect of microstructure on the (spatial and statistical distribution) of interface stresses in transversely loaded continuous fiber-reinforced composites. Instead of traditional unit-cell models, we use a parallel implementation of the boundary element method (BEM) to analyze large representative volume elements (RVEs) containing up to 144 individual fiber cross-sections placed within the domain of interest using a Monte Carlo (MC) algorithm. The BEM is well suited for this multi-inclusion modeling because of its relative accuracy and the ease of meshing complex geometries. By controlling the minimum allowable inter-fiber spacing, the MC algorithm allows for the generation of microstructures showing various degrees of homogeneity (or, disorder). Spatial correlation functions and overall properties are computed on these multi-fiber RVEs to ensure that their size allows for appropriate statistics to be inferred. After validating the computer code and giving some numerical examples, the effects of key microstructural and material parameters, namely the minimum inter-fiber spacing ( δ ), the fiber/matrix stiffness ratio ( E f / E m ) and the fiber volume fraction ( φ ) on the stress distributions are examined. Particular attention is placed on the statistics of the distribution of the maximum interface stresses computed on each fiber; these are found to follow a Weibull-like distribution, whose specific shape depends on material and microstructural parameters. This information can be readily incorporated into statistical models for the prediction of composite failure.
Separation of estrogen conjugates by high pressure liquid chromatography.

Abstract High pressure liquid chromatography using a prepacked commercial strong anion exchanger column (μ Partisil 10 SAX, 25 cm × 4.6 mm) was used to separate a mixture of eight estrogen conjugates. Chromato-graphic conditions using a 0.01 M potassium phosphate or 0.1 M NaCl as solvent in the isocratic mode are described for the separation of estrone glucosiduronate, 17β-estradio 1-3-g1ucosiduronate, 17β-estradio 1-17-glucosiduronate, estriol-3-glucosiduronate, estrio 1-16α-g1ucosiduronate, estriol-17-glucosiduronate, estrone sulfate and 17β-estradiol-3-sulfate. This system gives high resolution of the estrogen conjugates in small eluent volumes in less than 30 min. The advantages of this high pressure liquid Chromatographic system over other methods of separation are discussed.
Gallbladder response to a second dose of cholecystokinin during the same imaging study.

Patients on total parenteral nutrition or after prolonged fasting may require treatment with cholecystokinin (CCK) prior to hepatobiliary imaging. Some may also require evaluation of gallbladder (GB) contractility, and the need for a second dose of CCK may arise. It is not clear whether gallbladder function can be adequately evaluated with CCK when a previous CCK dose had already been administered. We studied ten normal subjects to evaluate GB response to a second CCK injection. The subjects received 20 μg/kg sincalide in a 3-min infusion prior to administration of technetium-99m disofenin. They then received an identical sincalide dose at 60 min postinjection, and imaging was continued for another 30 min to quantify GB contraction. Gallbladder ejection fraction (GBEF) values ranged from 42–98% (mean: 71.5±19%). Pretreatment with CCK does not preclude GB contraction evaluation with a second dose of CCK. Expected GBEF values are similar to those obtained with single CCK injections.
Design Optimization of a Shape Memory Alloy Actuated Morphing Aerostructure

Interest in shape memory alloys (SMAs) as lightweight actuators has motivated research into finding optimal morphing structure designs to replace conventional mechanisms in aerospace control systems. Prior to the development of robust constitutive modeling tools for these alloys, application design was based on trial-and-error studies conducted using an array of physical prototypes. Using this approach, a significant amount of time and materials were expended to produce each trial design. However, constitutive models now exist, implemented within a finite element analysis (FEA) framework, that can accurately and consistently predict the thermomechanical response of SMAs. This study considers the use of ModelCenter, a tool for automating simulation processes, coupled with the Abaqus FEA suite and a constitutive model to iteratively converge upon optimal designs in an automated fashion. The engineering design problem posed involves determining the configuration of a morphing aerostructure assembly with attached SMA flexures. Design inputs include material properties and component geometries. The objective is minimization of a cost function that quantifies the deviation of the computed actuation deflection from some target deflection. This paper presents a method for constructing this optimization problem, outlines the modeling tools used to execute each analysis, and highlights the results from the optimal design solution.Copyright © 2011 by ASME
Transmission of genital herpes by donor insemination.

This report describes a donor in a therapeutic donor insemination program who asymptomatically acquired a primary herpes simplex virus type 2 (HSV-2) infection from his long-standing sexual partner. His fresh semen was used to inseminate two HSV-seronegative recipients; in one a primary HSV-2 infection developed, and in one it did not. Direct evidence of transmission from donor to recipient was documented by restriction enzyme analysis of the HSV-2 isolates obtained from the donor's semen and from the recipient's cervix. Because of the possibility of asymptomatic acquisition and transmission of HSV-2, semen donors and their sexual partners should undergo serologic screening for genital herpes using new, type-specific HSV serologic techniques. (JAMA. 1989;261:3441-3443)
Comment on "Peierls Instability in the Two-Dimensional Half-Filled Hubbard Model"

The analyses of the two-dimensional Peierls-Hubbard model by Tang and Hirsch and by the present author are compared. While there is agreement with the principal conclusion of Tang and Hirsch, viz., that the effects of the Hubbard interaction on the Peierls bond alternation are different in one and two dimensions, I disagree on three related issues. First, the ($\ensuremath{\pi}, \ensuremath{\pi}$) phonon which dominates in the uncorrelated limit is different from the one Tang and Hirsch believe wins [($\ensuremath{\pi}, \ensuremath{\pi}$) along $x$ axis]. Second, the energy crossing between the ($\ensuremath{\pi}, \ensuremath{\pi}$) and ($\ensuremath{\pi}, 0$) phonons found by Tang and Hirsch for large magnitudes of the Hubbard interaction can occur only in the unrealistic limit of very strong bond alternation where the strength of the weak bond is close to zero. Finally, the disappearance of the bond alternation due to the Hubbard interaction is much more rapid than that calculated by Tang and Hirsch---the bond alternation should become weaker even at small $U$. This suppression of the bond alternation is indeed related to the long-range antiferromagnetism in two dimensions, as surmised by Tang and Hirsch.
The Microprocessor complex mediates the genesis of microRNAs

MicroRNAs (miRNAs) are a growing family of small non-protein-coding regulatory genes that regulate the expression of homologous target-gene transcripts. They have been implicated in the control of cell death and proliferation in flies, haematopoietic lineage differentiation in mammals, neuronal patterning in nematodes and leaf and flower development in plants. miRNAs are processed by the RNA-mediated interference machinery. Drosha is an RNase III enzyme that was recently implicated in miRNA processing. Here we show that human Drosha is a component of two multi-protein complexes. The larger complex contains multiple classes of RNA-associated proteins including RNA helicases, proteins that bind double-stranded RNA, novel heterogeneous nuclear ribonucleoproteins and the Ewing's sarcoma family of proteins. The smaller complex is composed of Drosha and the double-stranded-RNA-binding protein, DGCR8, the product of a gene deleted in DiGeorge syndrome. In vivo knock-down and in vitro reconstitution studies revealed that both components of this smaller complex, termed Microprocessor, are necessary and sufficient in mediating the genesis of miRNAs from the primary miRNA transcript.
Business ethics across cultures: A social cognitive model

Abstract This article presents a social cognitive model that identifies, defines and relates key comprehensive factors that impact on business ethical standards and conduct across cultures. In particular, national cultures serve as the social foundation for generating and shaping in a triadically interacting manner institutional, organizational, and personal factors. The model predicts that these three antecedent factors combine to influence the perceptions of business ethical standards uniquely in each culture. The model also predicts that the consequences of the resulting ethical or unethical behaviors feed back to modify the subsequent ethical standards and conduct. Examples and implications of this social cognitive model are provided throughout.
Using GPR for micro-analyses of soils and karst features on the Chiefland Limestone Plain in Florida☆

Abstract Karst and sand/limestone and sand/clay/limestone interfaces were investigated in two study plots on the Chiefland Limestone Plain in west-central Florida. The Chiefland Limestone Plain has many recently formed sinkholes and solution pipes that mark the landscape. Paleokarst features, such as relict sinkholes and solution pipes (with soils burying them), are not obvious due to the lack of surface expression. Prior to the development and use of ground-penetrating radar (GPR), accurate location of the paleokarst features, as well as determination of their configuration, was nearly impossible. Knowledge of the location of these features is important because the presence of these features indicates areas of subsurface instability. Additionally, in order to optimize the capability of GPR on karst, documentation of the effects of selected soil properties on the radar output, and the examination of the relationships of the clay layer, bedrock, and surface topography are imperative. The objectives of this study were: (1) to analyze selected soil properties and compare these properties to GPR performance in resoluting the sand/limestone (C/R horizons) and sand/clay/limestone (E/Bt/R horizons) interfaces; (2) to use GPR graphic data to identify paleo-sinkholes and solution pipes using computer-simulated diagrams of the limestone interface; and (3) to discuss implications for the association between the clay layer, bedrock, and surface topography in two study plots on the Chiefland Limestone Plain.
Transmethylation in immunity and autoimmunity

The activation of immune cells is mediated by a network of signaling proteins that can undergo post-translational modifications critical for their activity. Methylation of nucleic acids or proteins can have major effects on gene expression as well as protein repertoire diversity and function. Emerging data indicate that indeed many immunologic functions, particularly those of T cells, including thymic education, differentiation and effector function are highly dependent on methylation events. The critical role of methylation in immunocyte biology is further documented by evidence that autoimmune phenomena may be curtailed by methylation inhibitors. Additionally, epigenetic alterations imprinted by methylation can also exert effects on normal and abnormal immune responses. Further work in defining methylation effects in the immune system is likely to lead to a more detailed understanding of the immune system and may point to the development of novel therapeutic approaches.
Gadolinium Contrast Agent Selection and Optimal Use for Body MR Imaging

Proper selection of a gadolinium-based contrast agent (GBCA) for body magnetic resonance imaging (MRI) cases requires understanding the indication for the MRI exam, the key features of the different GBCAs, and the effect that the GBCA has on the selected imaging protocol. The different categories of GBCAs require timing optimization on postcontrast sequences and adjusting imaging parameters to obtain the highest T1 contrast. Gadoxetate disodium has many advantages when evaluating liver lesions, although there are caveats and limitations that need to be understood. Gadobenate dimeglumine, a high-relaxivity GBCA, can be used for indications when stronger T1 relaxivity is needed.
Floating crucible techniques for growing non-uniformly doped crystals

Abstract This paper presents a study of the impurity concentration profile of crystals grown by floating crucible technique with the impurity introduced in the outer crucible. When the distribution coefficient of the impurity is 0·1 or less, the concentration is found to increase linearly with the length of the crystal. Further, the concentration at the seed end of the crystal can be designed to start from any percentage of the final concentration. Crystals prepared by this method offer advantages for material or device properties studies in which concentration variation is an important factor. By introducing impurity of the other type in the floating crucible at the same time, compensated crystals can be grown with one impurity concentration varying as described while the other impurity concentration is maintained constant. Calculations of this variable concentration profile are made; families of curves are plotted and the results are discussed.
Staphylococcus aureus α-toxin. 2. Reduction of epidermal growth factor receptor affinity in PC12 cells

Abstract P. Lazarovici and K. -F. J. Chan . Staphylococcus aureus α-toxin. 2. Reduction of epidermal growth factor receptor affinity in PC12 cells. Toxicon25, 637 – 647 1987.—Staphylococcus aureus α-toxin, at sub-cytotoxic concentrations, inhibits both the 125I-labeled epidermal growth factor (EGF) binding and autophosphorylation properties of EGF-receptors in PC12 cells. This inhibition occurred only in intact cells and is probably due to a decrease in the affinity of the receptor for EGF. Streptolysin S and parcelsin could mimic the α-toxin effect below cytotoxic concentrations, as measured by a 51Cr release assay. In contrast, other membrane perturbing toxins with different lipid specificity, such as tetanolysin and cobra direct lytic factor, inhibited [125I]EGF binding only at cytotoxic concentrations. Staphylococcal α-toxin also stimulated 3-fold the specific binding of a radioactive tumor-promoting phorbol ester (PDBu) to PC12 cells at concentrations similar to those required for the inhibition of [125I]EGF binding. Although the exact mechanism for the inhibition of EGF binding by α-toxin has not been established, our results suggest that protein kinase C may be involved in this time-dependent process.
H 2 etching and epitaxial growth on 4H-SiC boule domes

Silicon carbide (SiC) is a semiconductor material intended for high-temperature and high-power switching device applications. One of the main concerns in SiC is basal plane dislocations (BPD), which cause devices to fail. Many researchers have strived to reduce these dislocations with some progress by varying pre-growth treatments and growth parameters; however, more efforts are needed to overcome the issue. Conventional 4H-SiC growth takes place on 8deg off-axis substrate, which results in smooth morphology due to step flow growth. However, it is known that growth on off-axis substrates allows many BPDs to propagate into the subsequent epilayers which comprise of the active region of the device. One way to reduce propagation of these dislocations is to grow on low off-axis material. Unfortunately as the off-cut is lowered, the morphology worsens and step bunching dominates. This study aims at reducing step-bunching on low off-axis angles (< 4deg) during both etching and epitaxial growth, while simultaneously reducing basal plane dislocations by experimenting on boule domes with various off-axis angles.
Signal extrapolation based on wavelet representation

The Papoulis-Gerchberg (PG) algorithm is well known for band-limited signal extrapolation. We consider the generalization of the PG algorithm to signals in the wavelet subspaces in this research. The uniqueness of the extrapolation for continuous-time signals is examined, and sufficient conditions on signals and wavelet bases for the generalized PG (GPG) algorithm to converge are given. We also propose a discrete GPG algorithm for discrete-time signal extrapolation, and investigate its convergence. Numerical examples are given to illustrate the performance of the discrete GPG algorithm.
Wideband mmWave channels: Implications for design and implementation of adaptive beam antennas

Millimeter wave mobile systems equipped with adaptive antennas show tremendous potential to provide much higher data rates than traditional cellular systems while offering comparable signal quality. This article presents channel measurement results obtained using a spread spectrum sliding correlator channel sounder at 28 GHz with an ultra-wide RF first null-to-null bandwidth of 800 MHz, collected in the dense urban environment of New York City. Statistics of multipath components, RMS delay spread, path loss, and angle distributions are investigated for antennas with different beamwidths. Theoretical beam combining analysis is performed, showing that the path loss can be reduced by 18.7 dB/decade in distance by coherently combining the four strongest beams at different pointing angles when compared to randomly pointed single beam antennas. Preliminary designs of beamforming and beam combining schemes using frequency domain equalization are proposed.
Fixed and Random Effects Selection in Mixed Effects Models

Summary We consider selecting both fixed and random effects in a general class of mixed effects models using maximum penalized likelihood (MPL) estimation along with the smoothly clipped absolute deviation (SCAD) and adaptive least absolute shrinkage and selection operator (ALASSO) penalty functions. The MPL estimates are shown to possess consistency and sparsity properties and asymptotic normality. A model selection criterion, called the ICQ statistic, is proposed for selecting the penalty parameters (Ibrahim, Zhu, and Tang, 2008, Journal of the American Statistical Association 103, 1648–1658). The variable selection procedure based on ICQ is shown to consistently select important fixed and random effects. The methodology is very general and can be applied to numerous situations involving random effects, including generalized linear mixed models. Simulation studies and a real data set from a Yale infant growth study are used to illustrate the proposed methodology.
Intraoperative Neurophysiologic Monitoring

Preface 1. Introduction, history, and staffing for intraoperative monitoring 2. The preoperative assessment 3. Magnetic stimulation 4. The operating room environment and team approach: pitfalls and technical factors 5. Basic pharmacology of anesthetic agents and their effects on neurophysiological monitoring 6. Somatosensory evoked potential monitoring with scalp and cervical recording 7. Transcranial electric motor stimulation: technique and exclusionary criteria 8. Electrocorticography and intraoperative electroencephalography 9. Brainstem auditory evoked potential monitoring 10. Pedicle screw application and electromyographic recording 11. Cranial nerve monitoring 12. Peripheral nerve monitoring: basics and indications 13. Special consideration in pediatric surgical monitoring 14. Intraoperative neurophysiologic monitoring of vascular disorders 15. Selective dorsal rhizotomies: technique and protocol for monitoring 16. Interpreting and reporting the neurophysiological data to the surgical team: how to do it and when is it indicated? 17. Intraoperative wake-up test 18. Postoperative studies and outcomes: clinical indications and usefulness of a postoperative study Index.