cssi/SciSciGPT-SciSciNet huggingface dataset:
Examining the dominant models and theories of international staffing policies and practices through the lenses of the African context and Chinese multinational construction enterprises in Africa

International staffing policies and practices of Chinese enterprises in Africa have given rise to a number of observations, critical comments, empirical support and rebuttals. One of the areas of r...
Confidence intervals for the largest autoregressive root in U.S. macroeconomic time series

This paper provides asymptotic confidence intervals for the largest autoregressive root of a time series when this root is close to one. The intervals are readily constructed either graphically or using tables in the appendix. When applied to the Nelson-Plosser (1982) data set, the main conclusion is that the confidence intervals typically are wide. The conventional emphasis on testing for whether the largest root equals one fails to convey the substantial sampling variability associated with this measure of persistence.
The NASA program for standardizing silicon solar cells

The present work describes briefly the goals of the recently organized Standardized Space Power Systems Office and its program for developing low-cost, standard power system components for spacecraft. The first step is the development of standard specifications for solar cells and covers. These include: (1) physical dimensions, materials of construction, appearance and integrity of solar cell and coverglass; (2) electrical performance characteristics of solar cell and optical characteristics of coverglass; and (3) sampling, inspection, and electrical and environmental tests needed to demonstrate compliance with the above specifications.
Selective vascular coagulation of rabbit colon using a flashlamp-excited dye laser operating at 577 nanometers

Previous studies have demonstrated that brief pulses of selectively absorbed optical radiation can be used to confine thermal injury to pigmented targets within tissues. We performed studies in rabbits to assess the usefulness of this technique for selectively coagulating the colonic vasculature. By measuring the optical absorbance of rabbit colon with a spectrophotometer, it was determined that hemoglobin exhibits strong absorption relative to the rabbit colon at a wavelength of 577 nm. Because light must be absorbed to affect tissue, it was hypothesized that laser pulses of this wavelength would selectively damage blood vessels. This hypothesis was tested by examining the effect of 300-microseconds-long 577-nm laser pulses on rabbit colon in vivo. For delivered radiant exposures between 4 and 8 J/cm2, selective coagulation of the colonic vasculature could be produced without damage to the surrounding colon. At greater radiant exposures, vessel hemorrhage was occasionally noted but no transmural thermal injury was produced with delivered radiant exposures as high as 22 J/cm2. This technique may form the basis of a safe and simple treatment of vascular lesions of the colon such as angiodysplasia.
Double-layer dynamics in the adsorption of tetrabutyl ammonium ions at the mercury-water interface: II: Capacitance transients

Abstract Capacitance-time transients show that the capacitance pit is formed by a process of nucleation and growth. The corresponding film can subsequently be transformed into another anion-containing film. Capacitance-time transients also provide evidence for the existence of a condensed layer containing anions at quite negative potentials.
Leg muscle function and fatigue during walking in spinal muscular atrophy type 3

Introduction: Spinal muscular atrophy (SMA) causes muscle weakness and fatigue. Better understanding of the relationship between weakness and fatigue may help identify potential targets for rehabilitation. Methods: Gait and surface electromyography (EMG) from 4 muscle groups were measured during the Six-Minute Walk Test (6MWT) in 10 ambulatory participants, aged 9–49 years. Average root mean square amplitude (RMS) of muscle activity was calculated. Strength was assessed using manual and quantitative methods. Results: RMS, stride length, and velocity decreased during the 6MWT. Knee flexor and hip abductor strength was associated with fatigue-related changes; overall strength correlated with disease duration; and leg strength was associated with 6MWT distance. Conclusions: Clinical measures are valid in assessing fatigue and function in SMA, and these assessments can be enhanced by use of gait analysis and EMG. Disease duration and strength measures may represent further stratification refinements when enrolling patients in clinical trials. Muscle Nerve 50: 34–39, 2014
Pharmacokinetic-pharmacodynamic relationships of bromfenac in mice and humans

The relationship between pharmacodynamic effect and plasma concentrations of the analgesic bromfenac was assessed retrospectively. The drug was administered in single doses of 5, 10, 25, 50, or 100 mg to patients with oral surgery pain. Concentration-effect curves were generated by a semiparametric pharmacokinetic-pharmacodynamic procedure. The bromfenac EC50 (the effect site concentration giving 50% of the maximum effect) was estimated to be 0.36 microgram/ml in patients when all five dose groups were combined, and an Emax model was used for pharmacodynamic response. A similar EC50 value, 0.40 microgram/ml, was obtained when bromfenac was tested in a mouse pain model. On the basis of combined-dose data, effect site concentrations were predicted to be above the analgesic EC50 for approximately 7-8 hours after a 50-mg bromfenac dose was taken in the fasting state. Predictions based on a pharmacokinetic-pharmacodynamic modeling procedure were in reasonable agreement with the clinical observations.
Soil moisture response to snowmelt timing in mixed‐conifer subalpine forests

Author(s): Harpold, AA; Molotch, NP; Musselman, KN; Bales, RC; Kirchner, PB; Litvak, M; Brooks, PD | Abstract: Western US forest ecosystems and downstream water supplies are reliant on seasonal snowmelt. Complex feedbacks govern forest-snow interactions in which forests influence the distribution of snow and the timing of snowmelt but are also sensitive to snow water availability. Notwithstanding, few studies have investigated the influence of forest structure on snow distribution, snowmelt and soil moisture response. Using a multi-year record from co-located observations of snow depth and soil moisture, we evaluated the influence of forest-canopy position on snow accumulation and snow depth depletion, and associated controls on the timing of soil moisture response at Boulder Creek, Colorado, Jemez River Basin, New Mexico, and the Wolverton Basin, California. Forest-canopy controls on snow accumulation led to 12-42cm greater peak snow depths in open versus under-canopy positions. Differences in accumulation and melt across sites resulted in earlier snow disappearance in open positions at Jemez and earlier snow disappearance in under-canopy positions at Boulder and Wolverton sites. Irrespective of net snow accumulation, we found that peak annual soil moisture was nearly synchronous with the date of snow disappearance at all sites with an average deviation of 12, 3 and 22days at Jemez, Boulder and Wolverton sites, respectively. Interestingly, sites in the Sierra Nevada showed peak soil moisture prior to snow disappearance at both our intensive study site and the nearby snow telemetry stations. Our results imply that the duration of soil water stress may increase as regional warming or forest disturbance lead to earlier snow disappearance and soil moisture recession in subalpine forests.
Adiponectin Blocks Interleukin-18-mediated Endothelial Cell Death via APPL1-dependent AMP-activated Protein Kinase (AMPK) Activation and IKK/NF-κB/PTEN Suppression *

The adipocyte-derived cytokine adiponectin is known to exert anti-inflammatory and anti-apoptotic effects. In patients with atherosclerotic cardiovascular disease, circulating levels of adiponectin correlate inversely with those of the proinflammatory, proapoptotic cytokine interleukin (IL)-18. The opposing actions of IL-18 and adiponectin on both cell survival and inflammation led us to investigate whether adiponectin signaling antagonizes IL-18-mediated endothelial cell death and to identify the underlying molecular mechanisms. Treatment with IL-18 suppressed Akt phosphorylation and its associated kinase activity, induced IκB kinase (IKK)-NF-κB-dependent PTEN activation, and promoted endothelial cell death. Pretreatment with adiponectin stimulated APPL1-dependent AMPK activation, reversed Akt inhibition in a phosphatidylinositol 3-kinase-dependent manner, blocked IKK-NF-κB-PTEN signaling, reduced caspase-3 activity, blocked Bax translocation, and inhibited endothelial cell death. The cytoprotective effect of adiponectin signaling was recapitulated by treatment with the pharmacological AMPK activator 5-aminoimidazole-4-carboxamide-1-β-riboside. Collectively, these results demonstrated that adiponectin reverses IL-18-mediated endothelial cell death through an AMPK-associated mechanism, which may thus have therapeutic potential for diminishing IL-18-dependent vascular injury and inflammation.
DNA topology confers sequence specificity to nonspecific architectural proteins

Topological constraints placed on short fragments of DNA change the disorder found in chain molecules randomly decorated by nonspecific, architectural proteins into tightly organized 3D structures. The bacterial heat-unstable (HU) protein builds up, counter to expectations, in greater quantities and at particular sites along simulated DNA minicircles and loops. Moreover, the placement of HU along loops with the “wild-type” spacing found in the Escherichia coli lactose (lac) and galactose (gal) operons precludes access to key recognition elements on DNA. The HU protein introduces a unique spatial pathway in the DNA upon closure. The many ways in which the protein induces nearly the same closed circular configuration point to the statistical advantage of its nonspecificity. The rotational settings imposed on DNA by the repressor proteins, by contrast, introduce sequential specificity in HU placement, with the nonspecific protein accumulating at particular loci on the constrained duplex. Thus, an architectural protein with no discernible DNA sequence-recognizing features becomes site-specific and potentially assumes a functional role upon loop formation. The locations of HU on the closed DNA reflect long-range mechanical correlations. The protein responds to DNA shape and deformability—the stiff, naturally straight double-helical structure—rather than to the unique features of the constituent base pairs. The structures of the simulated loops suggest that HU architecture, like nucleosomal architecture, which modulates the ability of regulatory proteins to recognize their binding sites in the context of chromatin, may influence repressor–operator interactions in the context of the bacterial nucleoid.
Comparison of Na Doppler lidar and MF radar measurements of meridional winds in the mesosphere above Urbana, IL

Abstract Simultaneous medium frequency (MF) radar and Na Doppler lidar measurements of meridional winds in the mesosphere (84– 96 km ) were collected at Urbana, IL in September and October, 1996. Comparisons on time scales of 1 h and longer and with height resolution of 3 km show that the two instruments measure winds that agree to within tolerances established by statistical estimation errors at night, but reveal large differences that cannot be explained by estimation errors in the daytime. After removing the altitude-independent component of both data sets, the wind estimates are shown to agree to within expectations based on measurement uncertainty at all times of the day. The most likely explanation for differences between the two data sets is determined to be undetected/uncorrected wavelength shifts in the lidar, which would introduce offsets into the measured winds at all altitudes.
Solution-Focused Brief Therapy for the Treatment of Sexual Disorders

The purpose of this article is to describe the use of solution-focused brief therapy (SFBT) as an approach to sex therapy. SFBT has been used to treat most clinical problems and populations, but until now has not been offered as an approach to sexual problems. This article describes SFBT and discusses its applications to sex therapy. A case example is included.
Imported skin diseases in dermatology

Millions of afflicted people suffer from conditions which Japanese dermatologists may rarely encounter. Many of our patients travel extensively either as part of work-related business trips or during vacationing. From three to ten percent of travelers experience skin, hair or nail disorders. With worldwide travel heightening exposure to the causative agents, there is an increasing likelihood that a patient with leishmaniasis, Boutonneuse fever, onchocerciasis, loaiasis, dengue fever, cutaneous larva migrans or other recently acquired skin conditions from a far away land will visit your office for diagnosis and treatment. The clinical characteristics, diagnostic tests and therapeutic options for such imported tropical diseases will be discussed.
Separate and Still Unequal: A Comparative Study of Blacks in Business Magazines

Through the use of a textual analysis, this study compares the contents of three business magazines--Forbes, Fortune, and Black Enterprise--and the way each covers the Black business community. The analysis reveals that the 2 mainstream business publications--Forbes and Fortune--focus almost entirely on covering the White-dominated corporate world, with the end result that Blacks and the Black business community are virtually invisible within their pages. The results support the work of other researchers who have found that the mainstream media are helping to perpetuate the White-dominated view of society that places minorities in general--and Blacks in particular--outside the norm. Black Enterprise, on the other hand, continues in the long tradition of the Black press, providing an alternative view of society through its focus on the Black business community.
Chaos in the dynamics generated by sequences of maps, with applications to chaotic advection in flows with aperiodic time dependence

In this paper we develop analytical techniques for proving the existence of chaotic dynamics in systems where the dynamics is generated by infinite sequences of maps. These are generalizations of the Conley-Moser conditions that are used to show that a (single) map has an invariant Cantor set on which it is topologically conjugate to a subshift on the space of symbol sequences. The motivation for developing these methods is to apply them to the study of chaotic advection in fluid flows arising from velocity fields with aperiodic time dependence, and we show how dynamics generated by infinite sequences of maps arises naturally in that setting. Our methods do not require the existence of a homoclinic orbit in order to conclude the existence of chaotic dynamics. This is important for the class of fluid mechanical examples considered since one cannot readily identify a homoclinic orbit from the structure of the equations.¶We study three specific fluid mechanical examples: the Aref blinking vortex flow, Samelson's tidal advection model, and Min's rollup-merge map that models kinematics in the mixing layer. Each of these flows is modelled as a type of "blinking flow", which mathematically has the form of a linked twist map, or an infinite sequence of linked twist maps. We show that the nature of these blinking flows is such that it is possible to have a variety of "patches" of chaos in the flow corresponding to different length and time scales.
The instability of the thin vortex ring of constant vorticity

A theoretical study indicating that vortex rings at moderate Reynolds numbers are unstable to azimuthal bending waves is presented. Only the case of a thin vortex ring with a core of constant vorticity in an inviscid flow is examined. The disturbance flow and the mean flow of the vortex ring are derived as asymptotic solutions near the core; the stability analysis is developed completely for a certain class of bending waves that are unstable on a line filament in the presence of strain. The vortex ring is found to be always unstable for at least two wavenumbers for which waves on a line filament of the same vorticity distribution would not rotate. Published experimental results are cited to support these conclusions.
Excitation, inversion, and relaxation mechanisms of the HCN FIR discharge laser

Millimeter/submillimeter rotational absorption spectroscopy has been used as a diagnostic probe of a cw HCN discharge laser. This sensitive technique allowed in situ absolute population measurements of a number of vibrational states of HCN (including the upper lasing state) and other pertinent molecules. This unique set of data, which was obtained under a variety of discharge and laser conditions, is directly related to excitation, inversion, and relaxation processes. Along with elucidating several fundamental aspects of inversion and relaxation these results also strongly indicate that the primary laser excitation mechanism is near-resonant energy transfer from vibrationally excited nitrogen, N2 (v=1), to the fundamental symmetric stretching mode of hydrogen cyanide, HCN(100), and subsequent thermal population exchange between HCN (100) and the upper laser state, HCN (110).
Gigawatt-level microwave bursts from a new type of virtual cathode oscillator

We describe experiments that demonstrate a new method for producing high-power microwave emission. The unstable oscillations of a virtual cathode which forms when a magnetized relativistic electron beam is injected into a circular waveguide generate the microwave radiation. In contrast to previous virtual cathode microwave generation techniques, electrons in the waveguide cannot be reflected back into the diode. Using this technique, we have produced 1.4 GW at 3.9 GHz with several hundred megawatts radiated in harmonic radiation.
Sociologists, social policy and the estranged poor: the selective inattention to the limits of success

Current antipoverty initiatives have been given impetus by the rediscovery of an “underclass”—a social category widely considered to be a distinctive subset of the poor. In the ensuing discussion, this aggregate has been related the Estranged Poor after Hochschild (1989). Social interventions granted the imprimatur of success are most frequently presented and/or interpreted as if they are applicable to all of the poor. It is argued here that this is an unwarranted exaggeration of effectiveness. The concept of a helping mismatch is introduced suggesting an intrinsic lack of articulation between formal agents of social intervention and the Estranged Poor who are therefore bypassed by even the most successful programs. Strains to exaggeration are described and explained as consequences of structural aspects of the remedial action system. Sociologists involved in social intervention have largely ignored the selectivity of success and too often prescribed directions for remedial action, which are irrelevant to the Estranged Poor. To acknowledge the limits of success can only encourage a more rational pursuit of our humanistic goals through the development of different approaches and strategies and, not incidentally, contribute to the credibility of our profession.
Optical throughput model

ITT Exelis builds electro optical telescopes and uses an optical throughput model in spreadsheet form to determine the transmission degradation due to contamination. The model can also be used to determine allowable contamination given a transmission requirement. Molecular contamination affects the transmission due to the absorbance of the optical contaminant while the particulate contamination affects the optical transmission due to obstruction and absorption of light, the model does not currently consider diffraction effects. The optical throughput model uses wavelength dependant absorption coefficients to determine the impact of the molecular contaminant. Optical transmission due to particles is analyzed by using the obscuration of the particle distribution. All optical elements in the telescope are analyzed by using the maximum angle of incidence for each optic. An expression was developed for non normal light assuming spherical particles and included light that was blocked by reflected incident light.
An application of bivariate exponential models and related inference

Abstract The purpose of this paper is to develop inference procedures for some bivariate exponential and related models with applications to an environmental problem.
Crystallization of cowpea chlorotic mottle virus.

Abstract Cowpea chlorotic mottle virus belongs to the brome mosaic virus group of the small spherical plant viruses. It contains 180 protein subunits, which are arranged on a T = 3 icosahedral surface lattice. The virus crystallizes in orthorhombic space group P 2 1 2 1 2 ( a = 394 A , b = 382 A , and c = 397 A ). The unit cell contains four virus particles, while the crystallographic asymmetric unit consists of one complete virion. X-ray diffraction data from the crystals extend to nearly 3.0 A resolution.
On Vehicle VOC and NOx Emissions from the Standpoint of the Tropospheric Ozone Problem

Ozone is formed in and downwind of urban areas from urban emissions of NOx and volatile organic compounds (VOCs) in the presence of sunlight. The main sources of VOCs in polluted air are motor vehicles, industrial solvents, processes in the petroleum and chemical industries, and vegetation. The main NOx sources are stationary-source fuel combustion (mainly electric utilities) and motor vehicles. Recent studies have demonstrated that VOC emissions from motor vehicles have been seriously underestimated, and this may well explain why ambient O3 has not responded well to control efforts. This review presents an overview of the sources, formation, and potential abatement strategies for O3 pollution in the troposphere, with particular emphasis on the mobile source contribution to O3 formation.
Pathways to Assignment of Payees

How clients come to be assigned representative payees and/or conservators to manage their funds is not well understood. We compared clients assigned a payee during a clinical trial of a money management-based intervention to those not assigned payees and examined antecedents to payee assignment. One year after randomization, significantly more clients assigned to the advisor teller money manager (ATM) money management intervention were assigned payees than participants in the control condition (10 of 47 vs. 2 of 43; p = .02); those assigned payees had lower baseline GAF scores and participated more in study therapies. Several ATM clients were assigned payees after third parties paid more attention to clients’ finances, and others after having negotiated storage of their funds with the ATM money manager during the study. Assignment of payees appears to be influenced by whether third parties critically attend to how clients’ manage funds and by clients’ receptiveness to having a payee.
The fabrication and material characterization of PZT based functionally graded piezoceramics

Functionally Graded Piezoceramics (FGP) increase actuator lifetime and provide complex deformations; however, to reap these benefits sophisticated grading and fabrication techniques beyond the conventional layered bonding techniques are required. This paper introduces the Dual Electro/Piezo Property (DEPP) gradient technique via MicroFabrication through CoeXtrusion (MFCX). The Dual Electro/Piezo Property (DEPP) grading technique pairs a high displacement lead zirconate titanate (PZT) piezoceramic with a high permittivity barium titanate (BT) dielectric. These compatible materials act synergistically to form dramatic gradients in permittivity across the structure, concentrating the electric field in the more piezoelectrically active region leading to electrically-efficient, large-displacement actuators; with the benefit of increased reliability stemming from the continuous gradients and monolithic nature of the ceramic. The DEPP variation was first evaluated independently of the MFCX process through fabrication and experimental characterization of a powder pressed bimorph. While simple one-dimensionally graded FGPs can be realized by this process, MFCX is needed for any complex, multidimensional gradient. The MFCX process was adapted for DEPP grading and demonstrated by creating a more complex linearly-graded FGP. Both the bimorph and linearly graded specimens had good material quality and generated high displacements correlating well with published FGP theory; with the linear gradient reducing internal stress levels, extending actuator lifetime. This paper presents a general FGP methodology that couples grading and fabrication to generate high yield, low cost monolithic actuators with complicated one-dimensional gradients. Extension of this research will pave the way for more complicated gradients yielding such deformation capabilities as warping, twisting, rippling, and dimpling.
A general approach to solution of partial differential equation systems

Abstract Computationally efficient physically accurate solutions have been found for broad classes of equations including systems of nonlinear partial differential equations without linearization by the decomposition method.
Intake and digestion by Holstein steers consuming different particle size fractions of broiler litter

Abstract Eight Holstein steers (153±13.6 kg body weight) were used in two simultaneous 4×4 Latin squares with 21-day periods to determine effects of separating deep-stacked broiler litter into small and large particle size fractions on feed intake and digestibility. Steers were fed diets with or without two sources of deep-stacked broiler litter (source A: 24% crude protein and 35% neutral detergent fiber; source B: 23% crude protein and 44% neutral detergent fiber). All steers were fed ground corn at approximately 0.5% body weight (dry matter basis). Bermudagrass hay was consumed ad libitum by Control steers (without broiler litter) or at 0.5% body weight (dry matter basis) for treatments with dietary broiler litter. Broiler litter was consumed ad libitum without separation (whole; W) or after separation (1-mm screen aperture) into small (S; 27 and 33% crude protein for A and B, respectively) and large (L; 22 and 18% crude protein for A and B, respectively) particle size fractions. Organic matter intake was increased (P=0.06) by dietary inclusion of broiler litter (4.55, 4.56, 4.63, 4.73, 4.24, 5.18, 4.74 and 4.59 kg day−1 for Control-A, W-A, S-A, L-A, Control-B, W-B, S-B and L-B, respectively; SE 0.229). Total tract organic matter digestibility was greater (P=0.08) for broiler litter source A than for B (57.4, 57.8, 54.9, 57.6, 56.5, 48.4, 46.9 and 54.8%; SE 3.83), and digestible organic matter intake tended (P=0.11) to be greater for source A (2.56, 2.64, 2.54, 2.72, 2.36, 2.51, 2.16 and 2.58 kg day−1 for Control-A, W-A, S-A, L-A, Control-B, W-B, S-B and L-B, respectively; SE 0.166). In conclusion, separating deep-stacked broiler litter into two particle size fractions did not alter feeding value as assessed by digestible organic matter intake by growing steers.
Oral melanoma in a gravid, HIV-positive woman.

A 30-year-old gravid, African-American womanwith multidrug-resistant HIV based on genotypetesting presented to the Department of Dermatologywith a 10-year history of asymptomatic hyperpigmen-tationofthegingivaandlip,whichhaddarkenedoverthe course of her current pregnancy. Physical exam-ination found an asymmetric, ill-deﬁned, 3-cm darkbrown and black plaque with irregular bordersinvolving the vermillion and mucosal lip, gingiva,and hard palate (Fig 1). There was no cervicaladenopathy.Initialpunchbiopsyfromtherightuppermucosal lip found a melanoma in situ involving thelateral margins. Subsequent incisional biopsy foundinvasive mucosal lentiginous melanoma with aBreslowdepthof1.45mm(Fig2).Pertinentlaboratoryfindings included a decreased CD4 count of 177 cellsper cubic millimeter anda viral load of624copies permilliliter.Aftermultidisciplinaryconsensuswithotolar-yngology and surgical oncology, the patient under-went wide resection with 1-cm margins after delivery.Sentinellymphnodebiopsyresultswerenegative.Thepatient is disease free 21 months after resection andhas required no further adjuvant treatment.
Protein analysis of defective interfering lymphocytic choriomeningitis virus and persistently infected cells.

Abstract Defective interfering (DI) lymphocytic choriomeningitis virus (LCMV) was purified from the culture fluids of BHK 21/13S and L-929 cells persistently infected with LCMV. DI LCMV sedimented in renografin-76 gradients to a density slightly less than standard (S) LCMV (1.13 vs 1.14 g/cm 3 ). Polyacrylamide gel electrophoretic analysis of [ 35 S]methionine-labeled DI virus revealed a major 63,000-dalton polypeptide corresponding to the S virion nucleoprotein (NP), and two minor polypeptides corresponding to the S virion 54,000− and 35,000-dalton glycopeptides. No differences in polypeptide composition were detected between the DI and S virions. Exposure of cells to DI virus before S virus challenge inhibited the intracellular synthesis of the NP. Cells persistently infected with LCMV released no detectable S virus or temperature-sensitive mutants but did release DI LCMV. The production of DI LCMV by these cultures was 10− to 100-fold lower than S virus production during acute infections. These persistently infected cells contained intracytoplasmic NP, detectable by immunofluorescence, but its rate of synthesis was too low to be detected by the radiolabeling methods used. Although present in the cytoplasms, detectable viral antigens were absent from the cell membranes of many of these persistently infected cells. Thus, cells persistently infected with LCMV produce relatively low levels of DI virus which can inhibit viral protein synthesis. These factors may act to render infected cells resistant to immunosurveillance mechanisms during persistent infections in vivo .
Bifurcation from simple eigenvalues for several parameter families

Abstract : If lambda = (lambda sub 1,..., lambda sub N) an element of the set R to the nth power, B,A sub 1,..., A sub N are bounded linear operators from a Banach space X to a Banach space Z, the concept of a simple eigenvalue for the operator B - the sum from j = 1 to j = N of lambda sub j A sub j is defined. It is then shown that bifurcation always occurs at simpe eigenvalues and the results are applied to a second order ordinary differential equation with boundary conditions at three distinct points. (Author)
Numerical simulation of heat transfer and fluid flow applied to exhaust manifold

Abstract A new calculation code has been developed to analyze thermal conduction in a complicated shape object coupled with heat flow. One of the characteristics of this code is to apply the finite volume method (FVM) to discretize the fluid region and the finite element method (FEM) to discretize the solid region. Presented in this paper are the background of the new code, and an example of thermal conduction analysis for an exhaust manifold, a critical engine part in terms of coupling a heat flow with the solid manifold in a complicated shape.
Experimental study of fuel decomposition and hydrocarbon growth processes for cyclohexane and related compounds in nonpremixed flames

C1 to C12 stable hydrocarbons, soot volume fraction, several major species, and gas temperature have been measured in a series of methane/air coflowing nonpremixed flames whose fuel was separately doped with 2000 ppm of cyclohexane, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, and benzene. The cyclohexadienes mostly dehydrogenated to benzene, while cyclohexane and cyclohexene mostly decomposed to C2, C3, and C4 hydrocarbons. Addition reactions were the main benzene source in the cyclohexane-doped flame, whereas both addition and dehydrogenation were important benzene sources in the cyclohexene-doped flame. Reaction pathways were identified in each flame from the hydrocarbon product distributions and from calculated rate constants of relevant reactions. Dehydrogenation was a minor pathway in the cyclohexane- and cyclohexene-doped flames because unimolecular dissociation, not H-atom abstraction, consumed the dopants and their conjugate radicals in these nonpremixed flames. The maximum soot volume fraction correlated poorly with the maximum benzene mole fraction in the cyclohexadiene-doped flames, which indicates that benzene formation was not a rate-determining step to soot production in those flames.
Electrical conductivity and seebeck voltage of Fe2O3, pure and doped, as a function of temperature and oxygen pressure

Abstract The electrical conductivity and Seebeck voltage were measured on 99.9997% Fe 2 O 3 as a function of temperature and oxygen pressure, and on donor- and acceptor-doped samples as a function of temperature. The results indicate Fe 2 O 3 is an intrinsic semiconductor above 650°C, where the conductivity is described by σ=9191.2 exp (−1.11 eV /kT)(1/Ω cm ) and it is oxygen-pressure independent. The Seebeck voltage shows Fe 2 O 3 is n-type below 800°C and p-type above this temperature. Conductivity measurements on doped samples were used to calculate the carrier mobilities and these are given by the expressions: μ ( electrons )=( 1998 T ) exp (−0.17 eV /kT)( cm 2 Vs ) , μ ( holes )= ( 9298 T ) exp (−0.29 eV /kT)( cm 2 / Vs ) . The electrons are the most mobile carrier below ≈800°C but the hole is more mobile above 800°C, and this probably explains the conversion from n- to p-type behavior. The concentration of electrons is greater than that of the hole above 650°C, and the carrier concentration product is given by ( np )= 1.34×10 42 exp (−0.78 eV/ kT ). The appropriate defect equation for intrinsic Fe 2 O 3 is 0= n + p and the formation expressions for the minor atomic defects are Fe 2 O 3 →2( Fe int N+ )+2N n + 3 2 O 2 , where N =2 or 3 and Fe 2 O 3 →2( Fe x Fe +3 V O ⋯ +6 n + 3 2 O 2 .
Sporidesmin toxicity in rabbits: Biochemical and morphological changes

Abstract The earliest lesion in rabbits dosed orally with 2 mg of sporidesmin per kg of body weight was necrosis of occasional hepatocytes 1 day after dosing. The most consistent lesion was a severe necrotizing cholangitis of medium and large-sized intrahepatic and extrahepatic bile ducts, first seen 2 days after dosing. Similar lesions were also present in the gall bladder of some rabbits. Expansion of portal triads with fibrous tissue and proliferating bile ductules progressed to pseudolobulation by 21 days. Other hepatic changes observed irregularly included large infarcts at the periphery of some lobes, and multiple small foci of coagulation necrosis in midzonal and periportal regions. Vascular necrosis and thrombosis, invariably adjacent to necrotic bile ducts, was presumably responsible for the hepatic necrosis. Serum cholesterol and total bilirubin concentrations and GGT activity reached peaks 15 days after dosing and were useful indicators of the severity of biliary lesions. Serum ID activity was the most useful indicator of hepatic necrosis following oral dosing with sporidesmin. The similarity between hepatobiliary lesions observed in sheep and rabbits with experimental sporidesmin toxicity suggests that the rabbit would be a useful model for studying methods of treatment and prevention of “facial eczema” in ruminants.
Statistics in Brief: An Introduction to the Use of Propensity Scores.

Randomized controlled trials (RCTs) are considered the gold standard of clinical research because randomization reduces the risk of extraneous factors influencing results of a study [2]. Nonetheless, high-quality, observational studies are at times more desirable than experimental studies (such as RCTs) owing to the their capacity to evaluate rare events, fewer ethical challenges with conducting the study, feasibility attributable to lower costs or infrastructure needs, and sometimes greater generalizability of the findings because of less-strict inclusion or exclusion criteria for patients and surgeons. Most orthopaedic studies are observational and retrospective [4, 7, 24]. Confounding exists when a third variable, which is not the exposure or outcome of interest, changes the relationship between the exposure and outcome being studied. For a variable to be a confounder, it must be (1) associated with the exposure of interest in the study, and (2) associated with the outcome. For a more real-life example, consider a study evaluating differences in time to revision between ceramic-on-ceramic and metal-on-polyethylene bearings used in THAs. The surgeon’s choice of bearing surface is likely not random; younger patients preferentially receive ceramic-on-ceramic bearings as opposed to metal-onpolyethylene bearings. If age also is related to the outcome (revision) in the study population, then age is regarded as a confounder. If the effect of age is not incorporated in the analysis, the estimate of the treatment effect (eg, odds ratio) will be biased. Confounding can be addressed using several methods with similar objectives during either the design or analysis phases of a study. Examples of methods used during the design of a study include restriction or matching, whereas those used during analysis include stratification, regression adjustment, instrumental variables techniques, and propensity score techniques. The purpose of this article is to describe confounding and how its effects can be minimized in observational studies with propensity score techniques. We provide guidance for when and how to use propensity scoring in studies.
MRSA with progression from otitis media and sphenoid sinusitis to clival osteomyelitis, pachymeningitis and abducens nerve palsy in an immunocompetent 10-year-old patient

A previously healthy 10-year-old patient with headache, otalgia, and hearing loss was diagnosed with pachymeningitis and methicillin-resistant Staphylococcus aureus otitis media and bacteremia. Despite antimicrobial therapy, intracranial extension progressed, including clival osteomyelitis, sphenoid sinusitis, cavernous sinus inflammation and cranial nerve palsies, until the sphenoid sinus was drained. This case exemplifies an aggressive MRSA intracranial infection that advanced despite antibiotic therapy.
Reproducibility of stress redistribution thallium-201 SPECT quantitative indexes of hypoperfused myocardium secondary to coronary artery disease.

Abstract To determine the reproducibility of quantitative indexes of hypoperfused myocardium by exercise thallium-201 single-photon emission computed tomography, duplicate studies were performed in 16 stable patients within 1 month. Twenty-three other patients, with intervals up to 13 months between studies, were retrospectively identified from medical records. Symptoms, weight, heart rate achieved and peak systolic blood pressure during the 2 studies were similar. Maximal counts circumferential profiles' polar maps were generated and divided into 3 vascular territories. The hypoperfused myocardium was defined as the percent stress profile points below the normal level. The observed values were compared between the 2 studies for each patient. Defect size ranged from 0 to 73%. The concordance correlation coefficient (a measure of the closeness of the data points to the line of identity) and mean absolute deviation were 0.94 and 4.5%, respectively, when all patients were considered together, 0.93 and 3.2%, respectively in the reproducibility group, and 0.94 and 5.1%, respectively, in the retrospective group. Inter- and intraobserver reproducibility were also very high. For individual vessels, the concordance correlation coefficients were all ≥ 0.89 and the mean absolute deviations between 3.7 and 9%. Thus, in stable patients with repeat thallium studies within a year, the percent hypoperfused myocardium is highly reproducible.
OBSERVATION OF PARTICLE TRAJECTORIES IN A WIDE GAP SPARK CHAMBER

Abstract A study has been made of the reliability with which the space angle of a spark in a wide gap spark chamber may be taken as a measure of the angular inclination of the trajectory of the initiating particle. For an 8 in. gap helium-filled chamber, efficiencies as high as 81% were observed for sparks making angles less than 8° with the plate normal and whose angular deviation from the actual trajectory was 3° or less. For larger angles, the efficiency was observed to decrease substantially. Threshold operating conditions for chambers with gaps of 2 in. and 5 in. are also discussed.
Metabolic effects of ethanol in regenerating rat liver

Abstract Ethanol inhibits metabolism of [1- 14 C]galactose to 14 CO 2 in normal rats liver; whereas in regenerating liver ethanol inhibition is markedly reduced. The limited effect of ethanol in regenerating rat liver is attributed to the formation of CO 2 from galactose via the hexosemonophosphate shunt which bypasses isotopic dilution by ethanol in addition to the resistance of the enzymes of galactose metabolism to ethanol toxicity.
Microvascular decompression for intractable singultus: technical case report.

OBJECTIVE: Intractable singultus is a rare but significantly disruptive clinical phenomenon that often accompanies other diseases but can present in isolation due entirely to intracranial pathology. We report a case of intractable singultus that improved after microvascular decompression and present a comprehensive review of singultus by discussing its similarity to other cases of microvascular decompression, its history and etiology, and its evolutionary basis. CLINICAL PRESENTATION: The patient exhibited intractable singultus for 15 years, resistant to multiple medical regimens. INTERVENTION: Microvascular decompression to relieve pressure on the tenth cranial nerve and medulla oblongata resulted in near total resolution of the singultus. CONCLUSION: Neurovascular compression should be considered a potentially reversible cause of intractable singultus, a significantly disabling clinical phenomenon.
Movement and deposition of sediment in the vicinity of debris-barriers

Accelerated erosion and the scour and deposition of sediment in streams have had, in many instances, harmful effects on the use of valley-floors as residential areas and for farming and grazing. Perhaps the outstanding significance of streams carrying a relatively large sediment-load is the effect on the silting of large reservoirs, the silting-rates of which determine not only the life of these reservoirs for flood-control purposes, but also the perpetuity of agriculture, cities, and industries, which are dependent on the water stored.
Experimental validation of mission energy prediction model for unmanned ground vehicles

Typical unmanned ground vehicles (UGVs) rely on rechargeable batteries for operation, so it is essential to ensure that the batteries will not be exhausted unexpectedly before the completion of the UGV mission. This demands an accurate model to predict the UGV mission energy requirement. For this purpose, two model estimation methods were proposed in the earlier work [1] using a vehicle longitudinal dynamics model. The first method used the least squares estimation (LSE) without using mission prior knowledge. The other method used Bayesian estimation to consider mission prior knowledge (e.g., road grade and rolling resistance). In this paper, we have validated several aspects of the methods via experiments, which includes: (1) evaluation of the measurement sensor capability, (2) examination of relationship between power consumption and vehicle velocity as well as road grade, (3) investigation of the estimation of UGV internal resistance, (4) study of the effect of different road surface conditions on power consumption, and (5) comparison of the performance between the proposed LSE and Bayesian estimation approaches in predicting the mission energy requirement. Therefore, the vehicle dynamic model has been validated. It has also been verified that the Bayesian estimation method is able to predict UGV energy consumption more accurately than the LSE method.
Dynamic magnetomechanical behavior of Terfenol-D/epoxy 1-3 composite

This paper presents an experimental investigation of the dynamic behavior of a 1-3 type magnetostrictive composite, with emphasis on the evaluation of fundamental material properties pertinent to device design. The fabricated 1-3 magnetostrictive composite comprises 51 percent volume fraction of Terfenol-D particulates embedded and magnetically aligned in a passive epoxy matrix. The dynamic magnetomechanical properties of the composite are measured as functions of bias field, drive field, and frequency. These properties include Young's moduli at constant magnetic field strength (EH3) and at constant magnetic flux density (EB3), magnetomechanical coupling coefficient (k33), dynamic relative permeability (ur33), dynamic strain coefficient (d33), mechanical quality factor (Qm), and the ratio of the dynamic strain coefficient to the dynamic susceptibility. Dependence of material properties on applied fields and frequency is observed with no evidence of eddy current losses. The observed eddy current effect agrees with the prediction of classical eddy current theory. This suggests that the composite can provide superior high-frequency performance as compared to monolithic Terfenol-D and laminated Terfenol-D systems. Implications for high-frequency applications of the material to resonance devices are also described.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Three surgical procedures for genuine stress incontinence: five-year follow-up of a prospective randomized study.

Abstract OBJECTIVE: Our purpose was to evaluate and compare the long-term results of the Kelly plication, modified Pereyra needle suspension, and Burch urethropexy for the treatment of stress urinary incontinence in women. STUDY DESIGN: One hundred twenty-seven consecutive women underwent surgery at the gynecologic urology division at Women's Hospital, Los Angeles county—University of Southern California Medical Center between January 1986 and June 1987. The only indication for surgery was stress urinary incontinence. Women with previously failed antiincontinence procedures were excluded. Fifty-three patients were premenopausal and 74 postmenopausal. History, physical examination, urethocystoscopy, cotton swab test, filling cystometry, urethral pressure profile at rest and on cough, and uroflowmetry were performed preoperatively, 3 months, 1 year, and 5 years postoperatively. The subjects and surgeons were randomly allocated to one of three surgical procedures: group 1 had anterior colporrhaphy with Kelly plication, group 2 had modified Pereyra needle urethropexy, and group 3 had Burch urethropexy. One hundred seven women were available after 1 year, and 93 were the subjects of the 5-year evaluation. Fisher exact text, χ 2 , t test, and paired t test were used for statistical analysis. RESULTS: The results of the 1-year postoperative evaluation has been previously published. The objective success rate for groups 1, 2, and 3 after 5 years was 37%, 43%, and 82%, respectively, and the difference was statistically significant. The drop in the success rate in 4 years was 26%, 22%, and 7% for groups 1, 2, and 3, respectively. Urodynamically all three procedures significantly increased the abdominal pressure transmission to the urethra, when successful. Ninety-one percent of women after the Burch procedure had a negative cotton swab test after 5 years compared with 46% for the Pereyra and 30% for the Kelly procedures. CONCLUSIONS: In our hands the Burch urethropexy has a higher cure rate that holds over time when compared with the modified Pereyra needle suspension and the Kelly plication. The lower incidence of the position cotton swab test in women after Burch urethropexy may be proof of a better anatomic suspension of the bladder neck.