cssi/SciSciGPT-SciSciNet huggingface dataset:
Assessment of a three-variable reduced kinetic scheme in prescribed turbulence

A chemical kinetic scheme for the combustion of complex hydrocarbon fuels is developed and assessed at conditions typical of high-intensity turbulent combustion. In the starting scheme, the fuel is assumed to pyrolyze at a global rate to CO and H2, which subsequently are oxidized in a series of elementary steps. The reduced scheme requires three variables: the mixture fraction xi, the fuel mass fraction Y(f), and a combined variable Y for CO and H2. The oxyhydrogen radical pool is assumed to be in a state of partial equilibrium, and the CO and H2 burn out as the radical pool decays via recombination reactions. The reduced scheme is compared with the starting scheme on combustion stability and CO/UHC emissions, in the context of the `partially stirred reactor` (PaSR) model developed earlier. The conditions are 30 atm, 1000 K inlet temperature, 2500 K equilibrium temperature (premixture equivalence ratio = 0.8), and 5 ms reactor residence time (in the perfectly stirred reactor (PSR) limit). PaSR simulations are conducted in the range 10-1000 Hz (mixing frequency), and in each case converge to a stochastic steady state and span the plug flow reactor-PSR limits smoothly. The reduced scheme performs well on flame stability (temperature) andmore » fuel mass fraction, but not as well on CO and H2, because the partial equilibrium assumption breaks down under conditions where significant amounts of fuel are present. Since only three variables are needed, the scheme is computationally fast enough for use in computational fluid dynamic studies of high-intensity turbulent combustion. 19 refs.« less
Some open questions about variational inequalities

We discuss some open questions especially concerning the coincidence set and the curve of separation in two-dimensional variational inequalities.
Evaluating the interaction between the manufacturing environment and planning and control systems

Abstract The choice of an appropriate infrastructure (systems and organizations) that is used to support the manufacturing process is often treated lightly in the literature. Historically, the selection of manufacturing planning and control systems has been influenced more by current “new wave” rather than by the environment faced by the firm. This study explores the interaction between the manufacturing environment and the planning and control system as it relates to performance. A mail survey of sample companies is used to classify manufacturing firms along the dimensions of production process, production volumes and the type of planning and control system used, and to estimate the processes-environment fit. Manufacturing performance is assessed through measures of inventory turnover, customer service, and delivery lead time. A random coefficient regression model is used to investigate if the fit between the manufacturing environment and planning and control systems is related to manufacturing performance.
Growing supranational identities in a globalising world? A multilevel analysis of the World Values Surveys

. Are globalisation and regional integration producing a postnational identity among a wide variety of publics? Using the World Values Surveys (WVS), this article shows that there is a global pattern in public attitudes toward supranational identity: the younger the respondent, the more supranational. Yet a life-cycle effect, as opposed to a generational one, underlies this pattern. A multilevel analysis confirms this age effect on supranational identification in 43 countries covered in the recent wave of the WVS, but provides little support for the idea that a country's integration into the global economy and world society promotes supranational attachments among mass publics, especially youths. Regional integration and globalisation appear either complementary or contradictory to this identity shift, depending upon how ordinary citizens perceive their country's involvement in the processes of regional integration and globalisation, respectively.
Designing Configurable, Modifiable and Reusable Components for Simulation of Multicore Systems

A simulation system for modern multicore architectures is composed of various component models. For such a system to be useful for research purposes, modifiability is a key quality attribute. Users, when building a simulation model, need to have the capability to adjust various aspects of a component, or even replace a component with another of the same type. Software design considerations can determine whether or not a simulation system is successful in providing such capabilities. This paper presents a few design tactics that we adopt in creating configurable, modifiable, and reusable components for Manifold, our parallel simulation framework for multicore systems. The main example component is MCP-cache, a coherence cache model. The ideas behind the tactics are general enough and should be useful to designers of similar systems.
Fraunhofer diffraction from a circular annular aperture with helical phase factor

Expressions and numerical results are given for diffraction from a circular annular aperture with a helical phase factor in the Fraunhofer approximation. The numerical results for the amplitude function are given for two values of the ratio of the aperture’s inner diameter to outer diameter, namely, 0.8 and 0.9, and for five values of the helical phase factor.
American Sign Language as an Accommodation During Standards-Based Assessments

In many states, standards-based education reform includes high-stakes assessment of children. Due to increasing pressure from the Individuals with Disabilities Education Act to include all children...
A New Method for Evaluating the Productivity Index of Nonlinear Flows

Summary This paper addresses the effects of nonlinearity of flows on the value of the productivity index (PI) of the well. Experimental data show that, during the dynamic process of hydrocarbon recovery, the PI stabilizes to some constant value, which, in general, is a nonlinear function of both the pressure drawdown and the production rate. Linear Darcy flow is well understood, and excellent approximate formulas are available for the PI in various well/reservoir geometries. To handle the more realistic nonlinear situation, the current practice is to solve the nonlinear problem multiple times for different values of production rate and then add ad-hoc corrective parameters in the linear formulas to reproduce the nonlinear nature of the flow. In this paper, we propose a rigorous framework to measure the PI of a well for nonlinear Forchheimer flows. Our approach, based on recent progress in the modeling of transient Forchheimer flows, uses both analytical and numerical techniques. It provides, for a wide class of reservoir geometries, an accurate relation between the PI for nonlinear Forchheimer flows and the PI for linear Darcy flows. The proposed method of building look-up tables and analytical formulas serves as an effective tool for fast PI evaluation in nonlinear cases.
Orthogonal bases of Brauer symmetry classes of tensors for the dihedral group

In this article necessary and sufficient conditions are given for the existence of an orthogonal basis consisting of standard (decomposable) symmetrized tensors for the class of tensors symmetrized using a Brauer character of the dihedral group.
"Ephedra-free" diet pill-induced psychosis.

The prevalence of obesity in the United States has increased from approximately 23% in 1990 to 33.8% in 2008. Multiple over-the-counter products claim to aid in weight loss under the pretense of being “natural” and “safe”. According to a national survey conducted in 2005 and 2006, 33.9% of respondents (who had made a serious weight-loss attempt) reported having used such a product. Following the FDA’s ban on ephedra-containing dietary supplements due to serious cardiovascular and neurological adverse reactions, manufacturers substituted ephedra with other substances, such as Citrus aurantium and marketed these products “ephedra-free”. We describe the development of severe psychosis in a middle aged woman after 2 weeks use of “ephedra-free” dietary supplements.
Structure, stability, and flexibility of ribosomal protein L14e from Sulfolobus solfataricus.

Ribosomal protein L14e is a component of the large ribosomal subunit in both archaea and eukaryotes. We report here a high-resolution NMR solution structure of recombinant L14e and show that the N-terminal 57 residues adopt a classic SH3 fold. The protein contains a tight turn between strands 1 and 2 instead of the typical SH3 RT-loop, indicating that it is unlikely to interact with neighboring ribosomal proteins using the common SH3 site for proline-rich sequences. The remainder of the protein (39 residues) forms a largely extended chain with a short helix which packs onto the surface of the SH3 domain via hydrophobic interactions. It has the potential of adopting an alternative structure to expose a hydrophobic surface for protein−protein interactions in the ribosome without disruption of the SH3 fold. 15N relaxation data demonstrate that the majority of the C-terminal chain is well-defined on the SH3 surface. The globular protein unfolds reversibly with a Tm of 102.8 °C at pH 7, making it one of the mo...
Justification and refinements of model B3 for concrete creep and shrinkage 2. Updating and theoretical basis

Following statistical evaluation in part 1, this part deals with the improvement of prediction by updating one or two parameters of the model on the basis of short term tests and theoretical derivation of some formulae. The updating of model parameters is particularly important for high strength concretes and other special concretes containing various admixtures, superplasticizers, water-reducing agents and pozzolanic materials. For the updating of shrinkage prediction, a new method is presented in which the shrinkage half-time is calibrated by simultaneous measurements of water loss. This approach circumvents the ill-posedness of the shrinkage extrapolation problem. Theoretical justifications of various aspects of the model are given and a new formula for the additional creep due to drying (or stress-induced shrinkage) is derived. The new model should allow a more realistic assessment of the creep and shrinkage effects in concrete structures, which significantly affect durability and long term serviceability of civil engineering infrastructure.
STAT3 signaling is induced by intercellular adhesion in squamous cell carcinoma cells

The signal transducer and activator of transcription-3 (STAT3) frequently activated during tumor progression has been linked to enhanced cell growth. In squamous cell carcinoma of the head and neck (HNSCC), STAT3 signaling has been shown to inhibit apoptosis and induce a more aggressive phenotype through the activation of specific signaling pathways. In the present study, we have examined the potential mechanism by which cell-cell contact initiates STAT3 activation. Using a panel of HNSCC cell lines, Ca(+2)-dependent cell-cell adhesion and adherens junction formation in multicellular aggregates triggered phosphorylation of STAT3-Y705 and STAT1-Y701. This intercellular adhesion-induced STAT3 activation was mediated by JAK and Src signaling and partially by EGFR signaling. In addition, immunolocalization studies revealed initial formation of phosphorylated STAT3-Y705 at nascent E-cadherin cell junctions with eventual translocation to the nucleus in cell aggregates. Adhesion-mediated STAT activation in monolayer and cell aggregate cultures required functional E-cadherin. These results indicate that, in HNSCC cells, cadherin-mediated intercellular adhesion induces STAT signaling that may modulate cell survival and resistance to apoptosis during tumor progression.
Formation pathways of ethynyl-substituted and cyclopenta-fused polycyclic aromatic hydrocarbons

Two novel classes of polycyclic aromatic hydrocarbons (PAH), those with ethynyl substituents (ethynyl-PAH) and those with externally fused five-membered rings (cyclopenta-fused PAH or CP-PAH), have recently been identified in the products of a variety of fuels and combustion/pyrolysis environments. However, the recently developed capacity for identifying these compounds has raised new questions about preferential reaction pathways. Specifically, across various fuels and operating conditions, experimentally observed products are (1) CP-PAH, which result from C 2 H 2 addition to an aryl radical, followed by cyclization to a cyclopenta ring and (2) ethynyl-PAH, which result from C 2 H 2 addition to locations on the aryl radical where cyclization is not possible. We have never observed ethynyl-PAH resulting from C 2 H 2 addition to an aryl radical at a point where cyclization into a five-membered ring is possible. To explain this behavior, we have performed AM1 semiempirical quantum chemical computations with group correction in order to examine the potential energy surfaces of the reaction pathways that lead to ethynyl-PAH and CP-PAH. We have performed computations for the parent aryl radical, possible ethynyl-PAH products, possible CP-PAH products, as well as intermediates and transition states, for C 2 H 2 addition to naphthalene, anthracene, phenanthrene, acenaphthylene, fluoranthene, and pyrene. Possible CP-PAH products are acenaphthylene, aceanthrylene, acephenanthrylene, pyracylene, cyclopenta[ cd ]fluoranthene, and cyclopenta[ cd ]pyrene. In all cases, we have found that, although energy differences between ethynyl-PAH isomers are very small (∼1 kcal/mol), the experimentally observed ethynyl-PAH is always the lowest energy isomer. Furthermore, the observed preference for cyclization to CP-PAH over formation of an ethynyl-PAH can be explained by the significantly lower energy barrier (23 vs. 36 kcal/mol) for the cyclization reactions. Finally, we have determined that, while not prohibited, the isomerization of ethynyl-PAH to CP-PAH requires significantly higher energy than the aryl-vinyl cyclization reactions, and therefore is not expected to make a significant contribution to the product distribution. These results are sufficiently consistent that the computation of reaction pathway energy surfaces can be used to identify likely ethynyl-PAH and CP-PAH products from the addition of C 2 H 2 to much larger parent PAH.
Mitral regurgitation in patients with advanced systolic heart failure

Abstract Background Mitral regurgitation (MR) may develop in patients with advanced systolic congestive heart failure (CHF) without organic mitral valve disease and contribute to worsening symptoms and survival. Surgical mitral annuloplasty improves symptoms in patients with advanced CHF, and percutaneous approaches to mitral annuloplasty are being developed. Our objective was to define the prevalence, clinical correlates, and prognostic implications of functional MR and the use of mitral annuloplasty in patients with advanced systolic CHF evaluated in a heart failure clinic. Methods and results We reviewed clinical, echocardiographic, and survival data from all patients with advanced systolic CHF (New York Heart Association class III or IV; ejection fraction ≤35%) resulting from ischemic or idiopathic cardiomyopathy who were evaluated at our heart failure clinic between January 1996 and September 2001. Of 716 patients with advanced CHF, 558 had satisfactory baseline echocardiograms performed at our institution. Among these patients, MR was severe in 24 (4.3%), moderate-severe in 70 (12.5%), moderate in 122 (21.9%), mild-moderate in 66 (11.8%), mild in 218 (39.1%), and absent or present as only a trace in 58 (10.4%). The severity of MR was confirmed by quantitative analysis in 72% of patients with hemodynamically significant MR (more than moderate). The severity of MR correlated with the severity of systolic dysfunction ( P P P P P P =.03) but not when controlling for age, sex, cause, New York Heart Association class, and ejection fraction ( P =.95). Only 3 patients subsequently underwent mitral valve repair. Conclusion Among patients with advanced CHF, hemodynamically significant MR is common. The severity of MR did not provide independent prognostic information in this group recognized to have uniformly high mortality.
Evaluation of elemental cadmium as a marker for environmental tobacco smoke.

The evaluation of cadmium as a marker of environmental tobacco smoke (ETS) has been carried out on the basis of several criteria. First, cadmium was found to be a good indicator source in ETS. For example, elevated Cd concentrations (4-38 ng/m 3 ) were measured in smoking areas compared with less than 2 ng/m 3 in ETS-free indoor air. Secondly, the cadmium concentrations in various types of unburnt cigarette tobacco are not significantly different, with the average concentration being 1.28 ± 0.17 μg of Cd/g of tobacco. Furthermore, the emission fraction of cadmium is quite large : approximately 44% of the total cadmium in cigarette tobacco is released in ETS. Cadmium in ETS was primarily found in the small particles (diameter less than 1 μm), indicating Cd to be a good marker of respirable ETS. Finally, the Cd concentration in ETS was observed to decay slowly and to increase linearly with the strength of the source. On the basis of these evaluations, it is concluded that cadmium is a good marker of ETS.
Singular stress amplification between two holes in tension

The singular stress amplification in either longitudinal on transverse tension in the ligament between two holes has been obtained by using a new singular asymptotic expansion for series.
PHOTOCHEMISTRY OF FLAVINS. II. PHOTOPHYSICAL PROPERTIES OF ALLOXAZINES AND ISOALLOXAZINES

Abstract. Pulsed laser photolysis at 347nm has been used to study the transient spectroscopy of alloxazine, lumichrome, lumiflavin, and riboflavin in acidic (pH 2.2) aqueous solution and in ethanol. Intersystem crossing quantum yields (φISC) were determined by a modification of the comparative laser excitation method which utilizes the variation of the triplet yield with intensity in conjunction with a kinetic model for the various photophysical and photochemical processes occurring during the pulse. Fluorescence quantum yields and lifetimes are also reported. Correction for quenching of the excited singlet state by H+ ions shows that, in neutral aqueous solution, intersystem crossing for flavins is an efficient process (φISC˜ 0.7) which, in conjunction with fluorescence, accounts for the fate of all absorbed photons. For alloxazine (φISC˜ 0.45) and lumichrome (φISC˜ 0.7) the results are more difficult to interpret owing to interconversion between alloxazine and isoalloxazine structures in the singlet excited state. For all four compounds, the quantum yield of products derived from the singlet excited state is estimated as ˜0.04. There is evidence of biphotonic product formation at high laser energies. In ethanol, where φISC for lumichrome is about twice that of lumiflavin, internal conversion between the excited singlet and ground states appears to be a significant process. Complete triplet-triplet absorption spectra in the region 260–750nm are reported. For lumichrome at pH 2.2 there is spectral evidence for isomeric triplet states which appear to be in equilibrium.
Deterrents to Divestiture

The deterrent effect of exit barriers, industry structural traits and competitive posture investments, on the firm's ability to divest a failing business with ease is explored, using analyses of th...
Grias theobromicarpa (Lecythidaceae), a new species from northwestern Ecuador

Grias theobromicarpa, a new species from northwestern Ecuador is described. This species is found in wet forests at ca. 1500 m elevation, and is distinguished by its erect petals that conceal the androecium, filaments fused to form a very distinct staminal tube, anthers that are oblong with cucullate connectives enclosing most of the thecae, and especially by its fruits, which are prominently ridged when fresh. The species is illustrated and its relationship with its closest relative, G. purpuripetala, from southwestern Colombia, is discussed.
Telemedicine from the Payor Perspective

Telemedicine applications, i.e. the use of telecommunication technologies to deliver health services over a distance, have demonstrated dramatic growth over the past decade. Reimbursement has emerged as a crucial issue as projects attempt to evolve from the demonstration stage to a mainstream component of health delivery. Payors around the world, both public and private, are currently evaluating telemedicine and making funding decisions. As summarized in this article, conclusive evidence regarding the clinical and/or cost effectiveness of telemedicine does not support generalizations regarding outcomes for telemedicine. However, further discussion in this paper demonstrates that this may not preclude payors from deciding to reimburse for services delivered via these technologies. Research from the US and the UK points to other significant historical contributors toward payor reimbursement decisions, such as consumer and market demand and payor mission.
Interferon-γ-induced gene expression in CD34 cells: identification of pathologic cytokine-specific signature profiles

Hematopoietic effects of interferon-γ (IFN-γ) may be responsible for certain aspects of the pathology seen in bone marrow failure syndromes, including aplastic anemia (AA), paroxysmal nocturnal hemoglobinuria (PNH), and some forms of myelodysplasia (MDS). Overexpression of and hematopoietic inhibition by IFN-γ has been observed in all of these conditions. In vitro, IFN-γ exhibits strong inhibitory effects on hematopoietic progenitor and stem cells. Previously, we have studied the transcriptome of CD34 cells derived from patients with bone marrow failure syndromes and identified characteristic molecular signatures common to some of these conditions. In this report, we have investigated genome-wide expression patterns after exposure of CD34 and bone marrow stroma cells derived from normal bone marrow to IFN-γ in vitro and have detected profound changes in the transcription profile. Some of these changes were concordant in both stroma and CD34 cells, whereas others were specific to CD34 cells. In general, our results were in agreement with the previously described function of IFN-γ in CD34 cells involving activation of apoptotic pathways and immune response genes. Comparison between the IFN-γ transcriptome in normal CD34 cells and changes previously detected in CD34 cells from AA and PNH patients reveals the presence of many similarities that may reflect molecular signature of in vivo IFN-γ exposure.
Synthesis and Reactivity of Dinuclear Platinum Complexes. NMR Spectra of [Pt2(PMe3)6][hfac]2 and an Unusual β-Diketonate Bridging Mode in [Pt2(μ-hfac)(PMe3)4][hfac]

Comproportionation of the platinum(0) complex Pt(PMe{sub 3}){sub 4} with the platinum(II) hexafluoroacetylacetonate complexes Pt(hfac){sub 2} or [Pt(hfac)(PMe{sub 3}){sub 2}][hfac] yields diplatinum species of stoichiometry [Pt{sub 2}({mu}-hfac)(PMe{sub 3}){sub 4}]-[hfac], 1, and [Pt{sub 2}(PMe{sub 3}){sub 6}][hfac]{sub 2}, 2, respectively. The NMR spectra and X-ray crystal structure of 1 show that the two platinum centers are chemically inequivalent; one is square-planar platinum(II) center, and the other is trigonal planar platinum(0) center. One of the hfac groups is anionic while the other bridges between the two platinum atoms. Each platinum center bears two PMe{sub 3} ligands, and the bridging hfac group, however, is bound to the other platinum center as an {eta}{sup 2} alkene ligand via its methine carbon and one of the two carbonyl carbons. The two platinum atoms do not interact directly with one another and are separated by 3.786(1) {angstrom}. The {sup 1}H NMR spectra of the hexakis(trimethylphosphine) diplatinum complex 2 are consistent with a structure in which the two platinum centers are connected by a Pt-Pt bond and the six PMe{sub 3} groups complete two mutually perpendicular square-planar coordination environments. Treatment of Pt(PMe{sub 3}){sub 4}. 57 refs., 4 figs., 2 tabs.
Human Cutaneous Graft-Versus-Host-Disease

The natural history of human cutaneous graft-versus-host disease (GVHD) has been described as a consequence of allogeneic bone-marrow transplants, but syngeneic and even autologous marrow transplants are now being recognized as being associated with similar, albeit less severe, changes. The histopathologic changes of both acute and chronic GVHD have been reported and show similarities to other idiopathic cutaneous disorders. The T-lymphocyte, specifically an OKT8+ cell, seems to play a major role in the pathogenesis of cutaneous GVHD. A recently described in vitro model of human cutaneous GVHD using skin explants co-cultured with lymphocytes holds some promise as a technique to further explore lymphocyte-skin interactions.
Identification of Surface-Exposed Domains on the Reducing Side of Photosystem I

Photosystem I (PSI) is a multisubunit enzyme that catalyzes the light-driven oxidation of plastocyanin or cytochrome c6 and the concomitant photoreduction of ferredoxin or flavodoxin. To identify the surface-exposed domains in PSI of the cyanobacterium Synechocystis sp. PCC 6803, we mapped the regions in PsaE, PsaD, and PsaF that are accessible to proteases and N-hydroxysuccinimidobiotin (NHS-biotin). Upon exposure of PSI complexes to a low concentration of endoproteinase glutamic acid (Glu)-C, PsaE was cleaved to 7.1- and 6.6-kD N-terminal fragments without significant cleavage of other subunits. Glu63 and Glu67, located near the C terminus of PsaE, were the most likely cleavage sites. At higher protease concentrations, the PsaE fragments were further cleaved and an N-terminal 9.8-kD PsaD fragment accumulated, demonstrating the accessibility of Glu residue(s) in the C-terminal domain of PsaD to the protease. Besides these major, primary cleavage products, several secondary cleavage sites on PsaD, PsaE, and PsaF were also identified. PsaF resisted proteolysis when PsaD and PsaE were intact. Glu88 and Glu124 of PsaF became susceptible to endoproteinase Glu-C upon extensive cleavage of PsaD and PsaE. Modification of PSI proteins with NHS-biotin and subsequent cleavage by endoproteinase Glu-C or thermolysin showed that the intact PsaE and PsaD, but not their major degradation products lacking C-terminal domains, were heavily biotinylated. Therefore, lysine-74 at the C terminus of PsaE was accessible for biotinylation. Similarly, lysine-107, or lysine-118, or both in PsaD could be modified by NHS-biotin.
Cation attachment in the analysis of polystyrene and polyethylene glycol by laser-desorption time-of-flight mass spectrometry

Al+, Cr+ and Cu+ gas-phase ions have found to attach effciently to two polymers, polystyrene and polyethylene glycol (PEG) in laser-desorption time-of-flight experiment, and are shown to be viable alternatives to be commonly used Na+, K+ and Ag+ ions. At high laser powers, in the range 8.0 × 107 to 2.0 × 108 W/cm2, ions can be attached by desorption from a support made of the apporoptite meal. An alternative method is to add the metal ion in the form of a salt containing the metal in the +1 oxidation state, when such salt are available. This method requires lowe laser powers, in the range 2.0 × 107 to 8.0 × 107 W/cm2. The two desorption/attachment methods are characterized by different optiomal time-delay values for recording of spectra. Polystyrence has been found to have a hight affinity for attachemnt to Al+, Cr+, and Cu+ than to K+, while PEG has ben found to have a hight affinity for K+ than for Al+, Cr+. These preferential attachments are discussed in terms of the hard and soft acids and bases principle.
Race and the Reproduction of Educational Disadvantage

Research has uncovered many mechanisms that exacerbate racial inequalities in achievement. Due to specialization within thefield, however, littlefocus has been devoted to the multitiered and often interconnected institutional nature of these processes. Matching datafrom the restricted-use National Educational Longitudinal Survey and the Common Core of Data, I hierarchically model the influence offamily/peer and educational institutionalprocesses simultaneously on the black-white gap in achievement. The modeling strategy used offers a more comprehensive understanding of the reproductive interinstitutional dynamics at work, suggesting strong linkages between family/peer group attributes and access to educational resources. I conclude by suggesting the need to extend this line of inquiry a step further still developing a theoretically driven contextual and spatial understanding of educational opportunity and achievement. The fortieth anniversary of the Brown vs. Board of Education decision was witness to enduring inequalities in educational opportunity and, consequently, educational outcomes. Substantial gains have indeed been made, and racial gaps have declined, yet disparities persist. The high school dropout rate for African Americans remains
Double-strand DNA hydrolysis by dilanthanide complexes.

Although there has been progress in developing artificial hydrolytic DNA cleaving agents, none of these has been shown to carry out the double-strand hydrolysis of DNA. We demonstrate that La(III) or Ce(IV) combined with the ligand 1,3-diamino-2-hydroxypropane-N,N,N', N'-tetraacetate (HPTA) in a 2 : 1 ratio can efficiently cleave supercoiled plasmid DNA at 55 degrees C within a 3-h period. Analysis of end-labeled restriction fragments cleaved by these complexes reveals 3'- and 5'-ends consistent with a hydrolytic mechanism. Unlike for other polydentate carboxylate complexes, plasmid DNA cleavage by La(2)(HPTA) or Ce(2)(HPTA) affords a significant amount of linear DNA with a considerable fraction of the supercoiled form still remaining. This result implies that La(2)(HPTA) and Ce(2)(HPTA) can carry out double-strand cleavage of plasmid DNA. La(2)(HPTA) and Ce(2)(HPTA) represent the first metal complexes demonstrated to be capable of double-strand hydrolytic cleavage of plasmid DNA.
An experimental study of microscopic and submicroscopic lipid inclusions in hepatic cells of the mouse

Lipid spherules of microscopic (1-μ) and submicroscopic (300–1000 A) dimensions were studied by electron microscopy in livers of mice that were normally fed, fasted, fasted and refed, or fed fat-free or high-fat diets. Tissues were fixed by perfusion with osmium and post-osmicated at 37°C. Submicroscopic inclusions were present in Golgi complex, endoplasmic reticulum, cytoplasmic vesicles near space of Disse, and in the space itself. The lipid of these inclusions was sufficiently unsaturated to be fixed and rendered insoluble by postosmication in all animals save those that were fed a diet rich in saturated fat or a fat-free high-carbohydrate diet (which induces synthesis of saturated fatty acids); in animals fed the two latter diets, the central mass of the inclusions escaped fixation and was dissolved during dehydration and imbedding. The inclusions were thus shown to reflect the character of the fatty acids most freely available in the cytoplasm of the hepatic cell in a given physiological state. On the basis of morphological and biochemical considerations, the submicroscopic inclusions were identified as secretion antecedents, elaborated by the liver for export to the blood. The larger lipid inclusions, which did not dramatically reflect changes in the degree of saturation of fatty acids available in the liver cell, were concluded to represent a more stable storage pool of hepatic-cell neutral lipid.
Turbulence characteristics of a fan-stirred combustion vessel

The authors previously applied experimental data on spark-ignited flame propagation in a constant-volume vessel to evaluate a phenomenological model of turbulent combustion. In this paper they present detailed information about the devices's turbulent velocity field, aspects of their measurement techniques, and the accuracy and repeatability of their turbulence data. Interest in these issues arises in part from the possible relation of velocity-field fluctuations to cyclic combustion variability in automotive engines.
Radiation for bone metastases

Pain management often is difficult in patients with bone metastases. Metastatic disease represents >40% of oncologic practice, and >70% of patients with metastatic disease have uncontrolled cancer-related pain. Significant morbidity caused by pathologic fracture and spinal cord compression can result from untreated bone metastases. Representing both a manifestation of systemic disease as well as causing localized symptoms, bone metastases require a multidisciplinary therapeutic approach. Radiation therapy provides both localized and systemic treatment options in addition to chemohormonal therapies and surgery. External beam irradiation provides palliation in >70% of patients through tumor regression of a localized lesion. Systemic radiopharmaceuticals treat multifocal disease either alone or as an adjuvant to external beam irradiation. Efficient and comprehensive management of bone metastases is imperative because of the associated symptoms, prior therapies, complex underlying medical problems, and clinical presentations that often require emergent interventions. Intensification of pain may be observed with hormonal therapy and systemic radiopharmaceuticals. Symptomatic relief from antineoplastic therapies generally requires 4-12 weeks and may be related to reossification. Symptoms, occurring due to the disease and/or while awaiting response to therapy, must be aggressively managed. Persistent or recurrent pain after therapy may be due to bony instability or fracture before reossification occurs. An Interdisciplinary Bone Metastases Clinic, with representatives from Diagnostic Radiology, Medical Oncology, Nuclear Medicine, Orthopedic Surgery, Pain and Symptom Management, Physical Medicine and Rehabilitation, and Radiation Oncology, was developed that allows coordinated evaluation, treatment, and symptom management of these complex clinical presentations. Cancer 1997; 80:1628-45. © 1997 American Cancer Society.
Charge ordering and phase competition in the layered perovskite LaSr 2 Mn 2 O 7

Charge-lattice fluctuations are observed in the layered perovskite manganite LaSr{sub 2}Mn{sub 2}O{sub 7} by Raman spectroscopy at temperatures as high as 340 K, and with decreasing temperature they become static, forming a charge-ordered (CO) phase below T{sub CO}=210 K. In the static regime, superlattice reflections are observed by neutron and x-ray diffraction with a propagation vector (1/4, -1/4, 0). Crystallographic analysis of the CO state demonstrates that the degree of charge and orbital ordering in this manganite is weaker than that in the three-dimensional perovskite manganites. Below T{sub N}=170 K, type-A antiferromagnetism (AF) develops and competes with the charge ordering, causing it to eventually melt below T{sup *}=100 K. High-resolution diffraction measurements suggest that the CO and AF states do not coincide within the same region of material, but rather coexist as separate phases. The transition to type-A antiferromagnetism at lower temperatures is characterized by the competition between these two phases. (c) 2000 The American Physical Society.
Spectral multiplicity of derived functor modules

Abstract Let Γ be a discrete torsion-free subgroup of a semisimple Lie group G such that the volume of Γ G is finite. We obtain a cohomological interpretation (in the sense of Langlands) of the multiplicity in the discrete spectrum of L 2 ( Γ G ) of an irreducible unitarizable derived functor module R sqCλ (after Zuckerman) with non-singular infinitesimal character.
Short- and Long-Term Outcome and Factors Predicting Survival After Surgical Tube Cystostomy for Treatment of Obstructive Urolithiasis in Small Ruminants

Objective— To evaluate outcome of small ruminants after tube cystostomy without urethral flushing. Study Design— Retrospective clinical study. Animals— Small ruminants (n=63; 50 goats, 13 sheep). Methods— Medical records (January 1996–October 2003) for all small ruminants undergoing tube cystostomy were analyzed. Signalment, laboratory data, intraoperative findings, urolith type, and postoperative outcome were compared. Long-term follow-up was obtained at 6 and ≥12 months postoperatively. Results— Most animals were castrated males. Pygmy goats were overrepresented. Mean time to normal urination after tube cystostomy was 11 days, and mean hospitalization was 14 days. Seventy-six percent of animals were successfully treated with tube cystostomy (90% of those discharged from hospital). Short- and long-term survival was good for those animals with follow-up data. Reobstruction occurred in <20% of animals at 6 and 12 months. Goats, castrated males, and animals with normal serum potassium, no fluid in the abdomen, or no urethral process amputation were more likely to survive. Stone type, bladder appearance, and age at castration were not associated with outcome. Conclusion— Surgical tube cystostomy without urethral flushing is an effective technique for resolution of obstructive urolithiasis in small ruminants. Clinical Relevance— Goats, small ruminants with an intact urethral process, absence of abdominal fluid, and serum potassium concentration <5.2 mEq/L at admission were all associated with survival after tube cystostomy. Castrated males may also be more likely to survive. These factors should be considered in management of small ruminants with urolithiasis.
Treatment Issues for Opioid-Dependent Women During the Perinatal Period

Opioid dependence has been studied with regard to its effects on the woman, the fetus, and the child for the past three decades, and it continues to be a serious problem that must be recognized and addressed by the health care delivery system in order to provide optimal medical care. The use of pharmacotherapy, such as methadone maintenance treatment (MMT), is only one of a variety of treatment modalities to provide optimal services for opioid-dependent women. The complete schema for treating opioid dependence in the perinatal period is complex and intense, but MMT serves multiple purposes. Primarily, it removes the addicted woman from the drug-seeking environment, eliminates the necessary illicit behavior, and prevents the peaks and valleys in the maternal heroin level that may occur throughout the day. In addition, maternal nutrition is usually improved and MMT patients become amenable to prenatal care and psychosocial rehabilitation. It is evident from the findings of numerous studies that when the physical, psychological, and socioeconomic issues of pregnant opioid-dependent women and their children are coupled with MMT, the potential physical and behavioral effects of psychoactive drugs on the mother, the fetus, the newborn, and the child may be markedly reduced.
Genotyping analysis available for patients after hematopoietic cell transplantation for multiple types of lysosomal diseases

in filter paper, initially for the detection of heparan sulfamidase (MPS IIIA) and beta-galactosidase (GM1-gangliosidosis, MPS IVB, galactosialidosis) deficiencies. We prepared filter paper samples with dried-leukocytes or dried-fibroblast (DLFP, DFFP) from healthy individuals and from patients with confirmed MPS IIIA or GM1 gangliosidosis by direct transfer of cell homogenates to filter paper discs. Heparan sulfaminidase and beta-galactosidase were tested by incubating samples with specific buffers and substrates. For heparan sulfamidase, a clear discrimination was found between normal controls and MPS IIIA patients both in DLFP and DFFP samples. For beta-galactosidase, distinction between normal controls and GM1-gangliosisdosis patients was evidenced only in DLFP samples so far. Although the method still needs further development, we conclude that assays for these two enzymes could be performed in dried-cell homogenates, and could be an useful tool for LSD identification, especially in areas where liquid blood samples usually need to travel several days to reach the reference laboratory.
Pericardial synovial sarcoma: challenges in diagnosis and management.

Introduction : Pericardial synovial sarcoma is an extremely rare tumor with poor prognosis. Timely diagnosis and aggressive multimodal management improves patient outcome. We present our experience of diagnosis and management of a young patient with monophasic synovial sarcoma arising from pericardium. Case : A 27-year-old man presented with dyspnea and cough of three weeks duration. Examination revealed sinus tachycardia, distant heart sounds and elevated jugular venous pressure. Chest X-ray showed widened mediastinum. Transthoracic echocardiogram (TTE) noted large pericardial effusion with tamponade physiology. Therapeutic pericardiocentesis yielded hemorrhagic fluid. Computed tomography (CT) of the chest showed persistent pericardial effusion and a left anterior mediastinal mass. Left anterior thoracotomy, pericardial window and left anterior mediastinotomy were done, revealing a well-encapsulated gelatinous tumor originating from the pericardium. Histology and immunohistochemical profile showed the tumor to be a monophasic synovial sarcoma. Fluorescent in-situ hybridization (FISH) was positive for SS18 (SYT) gene rearrangement on chromosome 18q11, substantiating the diagnosis. Work-up for metastases was negative. Neo-adjuvant chemotherapy with high dose ifosfamide led to substantial reduction in the size of the tumor. The patient underwent surgical resection and external beam radiation therapy (EBRT) post surgery. He had symptom-free survival for 8 months prior to local recurrence. This was managed with left lung upper lobectomy and follow-up chemotherapy with docetaxel. The patient is currently stable with an acceptable functional status. Conclusion: In patients with pericardial effusions of unknown etiology, multiple modalities of cardiac imaging must be employed if there is suspicion of a pericardial mass. CT and magnetic resonance imaging (MRI) are useful to evaluate for pericardial thickening or masses in addition to TTE. Treatment of synovial sarcoma is not well established. Surgery is the cornerstone of treatment. In non-resectable tumors, aggressive neo-adjuvant chemotherapy with ifosfamide followed by surgical resection and EBRT may lead to improved outcome.
Anti-blocking polyhedra

Abstract A theory parallel to that for blocking pairs of polyhedra is developed for anti-blocking pairs of polyhedra, and certain combinatorial results and problems are discussed in this framework. Blocking pairs of polyhedra are intimately related to maximum packing problems, anti-blocking pairs to minimum covering problems. Let B = { x ∈ R + n | Ax ≤ 1 }, where A is a non-negative matrix and 1 = (1,…, 1). The anti-blocker of the convex polyhedron B is defined to be the convex polyhedron B = {x ∈ R + n | x · B ≤ 1}. It is shown that B = B and a method is described for finding a non-negative matrix B such that B ={x ∈ R + itn | Bx ≤ 1 }. In particular, if A is the incidence matrix of a family of subsets of {1,…, n} having the property that each subset of a member of the family is again a member of the family, a method is described for finding the facets of the convex hull of the rows of A. It is shown that anti-blocking pairs are characterized by a min-max equality, the analog of the max-flow min-cut equality for blocking pairs, or by a max-max inequality, the analog of the length-width inequality for blocking pairs. Finally, the theory of anti-blocking pairs is applied to certain problems in extremal combinatorics. A main result is the following. If A and B are an anti-blocking pair of (0, 1)-matrices, then the min-max equality holds strongly for both ordered pairs A, B and B, A, i.e., both covering problems yA ≥ w, y ≥ 0, min 1 · y, and yB ≥ w, y ≥ 0, min 1 · y, have integer solutions y for all integer vectors w. Conversely, if A is a (0, 1)-matrix with anti-blocker B, and if the min-max equality holds strongly for A, B, then all essential rows of B are (0, 1)-vectors. This theorem bears on the perfect graph conjecture, and in fact proves a closely related theorem, which we call the pluperfect graph theorem.
Recent advances in the field of doping detection.

SUMMARY Patterns of doping in Britain have on the whole changed from the use of CNS stimulants and depressants to therapeutic substances, or to accidental doping by feeding contaminated food or food supplements. Progress in detection and identification is largely a result of improvements in separation and isolation, especially by gas chromatography, together with the introduction of mass spectrometry. Radioimmunoassay and high performance liquid chromatography promise to be important techniques in the future, especially in detection of anabolic steroids and corticosteroids. RESUME Les modalites du doping en Grande Bretagne ont dans l'ensemble change, delaissant les stimulants et les depresseurs du systeme nerveux au profit des substances therapeutiques, une autre forme pouvant etre l'emploi d'aliments ou de supplements alimentaires “contamines”. Les progres obtenus dans la detection et dans l'identification sont dus largement a l'amelioration des techniques de separation et d'isolement, notamment a la chromatographie gazeuse et a la spectrometrie de masse. Ulterieurement les techniques employant les radio elements et la chromatographie liquide devraient se reveler d'importance notamment pour la detection des corticosteroids et des anabolisants steroidiens. ZUSAMMENFASSUNG Die Dopingmethoden haben in England im allgemeinen vom Gebrauch ZNS-stimulierender oder-deprimierender Mittel gewechselt zu therapeutischen Substanzen oder zu zufalligem Doping durch die Verfutterung kontaminierten Futters oder von Supplementen. Fortschritte in Nachweis und Identifizierung sind vor allem das Resultat verbesserter analytischer Methoden fur die Trennung und Isolierung der Substanzen besonders durch Gaschromatographie zusammen mit der Einfuhrung der Massenspektrometrie. Radioimmunmethoden und hochleistungsfahige flussige Chromatographie versprechen in Zukunft Bedeutung zu erlangen besonders fur den Nachweis anaboler Steroide und von Corticosteroiden.
Cell death and free radicals: a mechanism for hydroxyurea teratogenesis.

Abstract Hydroxyurea is a drug which causes birth defects in a variety of animals. Its pharmacologic actions include rapid killing of proliferating cells and profound inhibition of the synthesis of DNA. The mechanism whereby hydroxyurea produces teratogenesis is unresolved although it is related to the pharmacologic actions. Careful reading of the scientific literature discloses several putative mechanisms for the teratogenic action of hydroxyurea, which account for the inhibited synthesis of DNA, but do not explain the rapid onset of cell death. This paper presents a hypothesis that hydroxyurea causes rapid cell death through the initiation of uncontrolled free radical chain reactions. In vitro biochemical experiments have demonstrated the ability of compounds containing a hydroxylamine group (such as hydroxyurea) to form H 2 O 2 and intermediate free radicals in biological fluids. Free radicals propagate themselves through chain reactions and can react swiftly and indiscriminately with the macromolecules of cells. Radical reactions are able to devastate cellular metabolism quickly by inactivating enzymes, cross-linking DNA, and altering membrane functions through lipid auto-oxidation. Preliminary experiments utilizing an antioxidant to counteract the free radical effects appear to support the hypothesis that the rapid cell death is caused by aberrant free radical reactions.
Weak bipolarizable graphs

We characterize a new class of perfectly orderable graphs and give a polynomial-time recognition algorithm, together with linear-time optimization algorithms for this class of graphs.