cssi/SciSciGPT-SciSciNet huggingface dataset:
Fundamental concepts and limitations in precision pointing and tracking problems

In this paper, we first describe the generic pointing and tracking problems in a general dynamical system/state-space context. Then, we analyze the information-theoretical aspects of the various uncertain signals in those problems, and establish some fundamental performance limitations those uncertainties induce, using various results and principles of modern control theory. It is shown that the introduction of 'waveform models' for uncertain signals, leading to an extended-state formulation of pointing and tracking problems, is the most effective rational means of coping with those fundamental limitations.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Peacekeeping and the Gender Regime: Dutch Female Peacekeepers in Bosnia and Kosovo

This article addresses the issue of women participation in peacekeeping missions by focusing on two North Atlantic Treaty Organization Dutch peacekeeping units in Bosnia (SFOR8) and Kosovo (KFOR2). I argue that soldiers are ambivalent toward what is perceived the “feminine” aspects of peace missions. Although peacekeeping is a new military model, it reproduces the same traditional combat-oriented mind-set of gender roles. Therefore Dutch female soldiers are limited in their ability to perform and contribute to peace missions. Both peacekeeping missions and female soldiers are confusing for the soldiers, especially for the more hypermasculine Bulldog infantry soldiers. Both represent a blurred new reality in which the comfort of the all-male unit and black-and-white combat situations are replaced by women in what were traditionally men's roles and the fuzzy environment of peacekeeping. At the same time, both are also necessary: peacekeeping, although not desirable, has become the main function for Dutch so...
Inferring network paths from point observations

The use of geographically referenced point data, such as that obtained from global positioning systems GPS, is rapidly increasing. However, due to error and uncertainty inherent in most geographic datasets, the ability to accurately associate these point locations with other layers of geographic data is still a challenge. One difficulty in particular is how to associate spatially and temporally referenced point-based observations of a network activity with a network topology such that a continuous network path can be best inferred. In this article, an optimization method for inferring a network path from a temporal sequence of point observations of location is presented. An application to GPS data is provided to highlight various characteristics of the proposed modeling approach relative to several other available techniques.
Books Abroad / World Literature Today: Past, present and future

L'article retrace les points forts des 75 annees d'histoire de la revue litteraire trimestrielle Books Abroad, fondee en 1927 par le Dr Roy Temple House a l'University of Oklahoma, et rebaptisee en 1977 World Literature Today. Son objectif premier est de defendre l'internationalisme dans la culture, avec par exemple la creation du premier prix litteraire international, le Neustadt International Prize for Literature.
A General Semicausal Stochastic Model for Turbulence/Radiation Interactions in Flames

This paper presents a general two-dimensional non-stationary semicausal model for the simulation of mixture fraction, which improves our previous causal model. The proposed model includes not only the pre-correlation predictors (both in time space and geometric space) as well as the cross-correlation predictors, as in the causal model, but also post-correlation predictors. The latter makes possible the consideration of interactions of a scalar, such as mixture fraction, at a physical location with that of all its adjacent locations. It has also been shown that the complicated second-and higher-order correlation predictors can be neglected in the semicausal simulation of mixture fraction. To show the validity of the model, the stochastic mean and variance of the spectral intensities at different wavelengths were predicted and compared with detailed experimental data for turbulent carbon monoxide/hydrogen/ air diffusion flames having different Reynolds numbers. These comparisons showed excellent agreement with existing data and the improvement over the prior causal model.
Dielectric coefficient and density of subcooled liquid hydrogen

Abstract The results of high precision dielectric coefficient measurements of subcooled liquid oxygen in the temperature range from 56 to 91 K and under pressures up to 1 MPa are reported. The measurements are performed using a three-terminal flat plate capacitor and a single-frequency, ultra-precision capacitance bridge. Measurement results are combined with the previously published data in different pressure and/or temperature ranges to express the dielectric coefficient and the Clausius–Mossotti relation in an equation form. This new expression covers both the liquid and the gaseous state, and predicts the density of oxygen to better than 0.1% over the entire range of interest. The results reported in this paper are expected to be especially useful for capacitance-based measurements involving fluid oxygen such as liquid level and void fraction measurements of two phase flow.
Inconsistency in Campbell's rhetoric: Explanation and implications

George Campbell's Philosophy of Rhetoric is an integration of eighteenth‐century psychological and philosophical thought with classical rhetorical concepts. This integration, however, contains a methodological‐epistemological inconsistency. Campbell advocated verification through observation but also accepted the Common Sense dictum that people possess the certainty of original knowledge. Analysis and explanation of the inconsistency reveal important implications for current‐day theorizing about communication.
The influence of organic additives on the thickness distribution of tubular metallized through-holes

Abstract Through-hole plating capability was examined for process electrolytes made up with various organic additives. Tafel plots were obtained from cyclic voltammetry using the rotating-disc technique. The levelling capability of the electrolytes was obtained from coulometry and in situ microgravimetry in combination with optical microscopy, the throwing power for through-hole plating from the thickness ratio center of hole-plane surface outside the hole. It was shown that a high throwing power correlates with a low levelling capability. The results shed some light on the inhibiting character of the process electrolytes used.
Statistical Analysis of Yield Trials with MATMODEL

Yield trials guide agronomic recommendations and breeding selections, but often are limited by inaccuracy, missing data, and the difficulty of understanding complex genotype-environment interactions. Recent studies have shown that a statistical model rather new to agriculturalists, the Additive Main Effects and Multiplicative Interaction (AMMI) model, can reduce these limitations. This paper introduces MATMODEL, a convenient program for the required calculations that runs on IBM compatible personal computers with MS-DOS (PC-DOS) 2.1 or higher and on the Apple Macintosh
Differential sputtering of MgO/Au cermet films and its application to high-yield secondary-electron emitters

Very large differential-sputtering effects in fine-grained (particle size < 50 A) MgO/Au cermet films have been observed by Auger electron spectroscopy. Under Ar-ion bombardment, the surface Au content was found to decrease exponentially with time by up to a factor of 20. A theoretical model for differential sputtering of granular systems is presented that gives good agreement with the experimental data. The differential sputtering produces a MgO-rich surface layer and therefore results in excellent secondary-electron-emission properties for low-energy incident electrons.
The effect of thickness, pore size and structure of a nanomembrane on the flux and selectivity in reverse osmosis separations: a molecular dynamics study

Abstract Molecular dynamics simulations examine the effect of pore size, structure and membrane thickness on flux and selectivity in reverse osmosis. Membranes are modeled using layers of barrier molecules tethered harmonically to periodic lattice sites. Permeation occurs within a Knudsen like regime where close confinement in nanopores precludes water–water interactions, leaving water–pore interactions to determine hydraulic resistance. Results show the solvent flux to be rather insensitive to an appropriately defined tortuosity. Ion selectivity seems to correlate primarily with overall hydraulic resistance, irrespective of the number of membrane layers.
High gain preamplifier module (PAM) engineering prototype for the National Ignition Facility (NIF) laser system

We describe recent results and developments in the preamplifier module engineering prototype located in NIF's front end or Optical Pulse Generation system. This prototype uses the general laser design developed on a physics testbed and integrates NIF type packaging as well as controls and diagnostics. We will present laser, mechanical and electrical hardware designed and built to data as well as laser energetics measurements.
Multiscale imaging of human thyroid pathologies using integrated optical coherence tomography (OCT) and optical coherence microscopy (OCM)

We evaluate the feasibility of optical coherence tomography (OCT) and optical coherence microscopy (OCM) for imaging of benign and malignant thyroid lesions ex vivo using intrinsic optical contrast. Thirty four thyroid gland specimens were imaged from 17 patients, covering a spectrum of pathology, ranging from normal thyroid to neoplasia and benign disease. The integrated OCT and OCM imaging system allows seamlessly switching between low and high magnifications, in a way similar to traditional microscopy. Good correspondence was observed between optical images and histological sections. The results provide a basis for interpretation of future OCT and OCM images of the thyroid tissues and suggest the possibility of future in vivo evaluation of thyroid pathology.
Spectral Lineshape in Extended Two-Dimensional Electronic Systems

Abstract The close proximity and relative orientation of molecules within the aggregated portion of a monomolecular layer may lead to collective behavior, where molecules no longer act independently but create an extended electronic network. In most previous discussions, the axial orientation has been presumed to be discrete, although this condition is unlikely to be realized in any practically fabricated organic monolayer. The lineshape expressions developed here, based on the dipole-dipole coupling of adjacent transition moments, are general in nature and indicate that the presence of even a narrow orientational distribution can significantly affect the spectral lineshape of the aggregated species. Utilizing molecular parameters from hemicyanine dye molecules, electronic spectral lineshapes are determined as a function of intermolecular spacing, a 1 , ensemble average orientation, 〈θ〉, and orientational distribution standard deviation, σ θ . The transition frequency of the aggregate is shown to be dependent on the axial distribution within the associated structure, causing significant variations for 〈θ〉 > 45° from surface normal. In fact, a 1.43-eV decrease in the transition energy is calculated for σ θ from 0.5° to 5.0° at 〈θ〉 = 75° and with an intermolecular spacing equal to the length of the transition dipole. The aggregate linewidth is also dependent on the orientational distribution, with σ θ causing an increase in linewidth under all conditions examined. For the same conditions described above, the variation in the linewidth increase ∂Δ v /∂σ θ > 1800 cm -1 /°. Although the orientational distribution does not have this profound effect under all structural conditions, this contribution to the overall aggregate lineshape is clearly more pronounced than has been previously appreciated.
Synthesis and structure of copper- and yttrium-rich YBa2Cu3O7−x superconductors

Abstract Copper- and yttrium-rich modifications of the YBa2Cu3O7−x superconductors have been synthesized using a liquid nitrogen quenched followed by annealing. In both types of cation-rich materials the starting materials is highly disordered but upon annealing the extra copper or yttrium precipitates out in the form of planar defects normal to the c axis which on annealing at higher temperatures start to coarsen from single plane defects to multiple plane defects and become better ordered normal to the c axis. In all cases X-ray diffraction gives an average orthorhombic structure. The existence of these defects appears to have no effect upon the sharpness of the superconducting transition for specimens annealed to 800°C, leads to a small broadening of the transitions in specimens annealed at 700°C, while the specimens annealed at 300°C show only a hint of superconducting behavior. This supports the view that these materials are one- or two-dimensional superconductors normal to the c axis with only a small contribution to the bulk superconductivity along the c axis.
Validating a claims-based method for assessing severe rectal and urinary adverse effects of radiotherapy.

Objective To validate a claims-based algorithm for detecting severe rectal and urinary adverse effects (AEs) of radiotherapy (RT) to inform the design and interpretation of outcomes studies, using administrative datasets to detect such RT AEs. Methods An institutional billing analysis was performed to identify patients managed with RT for prostate or cervical cancer at the University of Minnesota, between 2000 and 2006. A priori, we identified Current Procedural Terminology procedural codes consistent with treatment for severe RT AEs. A retrospective chart review and a billing (ie "claims") analysis were performed to detect the procedures used to treat RT AEs. The accuracy of the claims-based algorithm was compared with chart review (the reference standard). Results On chart review, 31 patients (7.6%) with severe rectal and urinary RT AEs were detected among 406 patients with nonmetastatic cancer at diagnosis. The most common AE was ureteral stenosis (25% of all AEs). The sensitivity and specificity of the claims-based analysis were 75% and 100% respectively for urethral stricture, 100% and 99% respectively for ureteral stricture, 60% and 100% respectively for radiation cystitis, 88% and 100% respectively for rectal or urinary fistula, and 88% and 100% respectively for radiation proctitis. Conclusion We demonstrated an excellent specificity and yet fairly good sensitivity of our claims-based algorithm for detecting treatment of urethral stricture, rectal or urinary fistulas, radiation proctitis, and ureteral stricture. These data might inform the design and interpretation of studies using claims-based methods for the detection of severe urinary AEs of pelvic RT.
Design of the Bronchial Tree

The bronchial tree is so designed that the functions of the lung can be carried out with minimum entropy production.
Regeneration of perivascular adrenergic innervation in rat tibial nerve after nerve crush

Adrenergic innervation of blood vessels in the rat tibial nerve during degeneration and regeneration was studied using the formaldehyde-induced fluorescence method. The left sciatic nerve was crushed with suture threads to produce a 4-mm length of crushed nerve. At 1, 3, 7, 14, 28, 56 and 84 days after nerve crush, degenerative and regenerative changes in the nerve were verified using light microscopy. At each time point, adrenergic innervation was examined in epi-perincurial whole mount and nerve cross-section preparations. One day after nerve crush, fluorescence of adrenergic nerve fibers in the endoneurium was absent. Fluorescent adrenergic nerve fibers reappeared in the endoneurium at day 56 and reached the control density by 84 days. In the epi-perineurium, adrenergic innervation of small and medium-size arterioles was absent at 3 days, in large arterioles at 7 days. At 56 days, all epi-perineurial arterioles were reinnervated by a faint, sparse adrenergic network, which reached the control density at 84 days. The results suggest that adrenergic innvervation in the rat peripheral nerve is lost during nerve degeneration, but recovers when the nerve has regenerated.
High-Power Multi-Stage Rankine Cycles

This paper presents an analysis of the multi-stage Rankine cycle aiming at optimizing the power output from low-temperature heat sources such as geothermal or waste heat. A design methodology based on finite-time thermodynamics and the maximum power concept is used in which the shape and the power output of the maximum power cycle are identified and utilized to compare and evaluate different Rankine cycle configurations. The maximum power cycle provides the upper-limit power obtained from any thermodynamic cycle for specified boundary conditions and heat exchanger characteristics. It also provides a useful tool for studying power cycles and forms the basis for making design improvements.
The surface ozone record from the regional air pollution study, 1975–1976

Abstract Surface ozone concentrations recorded by the Regional Air Monitoring System (St. Louis) during 1975–1976 are presented in time series form. The plotted concentrations are the daily maximum 1-h average and the daily inflow, that representative of air flowing into the metropolitan region during a 4-h midday period. In general, the inflow varies from 30 ppb in the winter to 70 ppb in the summer, but under strong high pressure systems may approach or exceed 120 ppb. Evidence of local ozone production is apparent, with the highest recorded maximum in the two years being 255 ppb. Scatter diagrams are used to display the dependencies of ozone concentrations on temperature, solar radiation and wind speed. A strong dependence on temperature is particularly notable.
Collision-enhanced Hanle resonances and transverse optical pumping in four-wave light mixing in Na vapor.

Collision-enhanced Hanle resonances in the 3 $^{2}S_{1/2}$ electronic ground state of Na atoms have been studied in a phase-conjugate four-wave light-mixing geometry. Narrow resonances in zero magnetic field have been observed at very high inert-buffer-gas pressures, with a width of 21 mG, or less than 10 kHz, full width at half-maximum. The intensity and the width of these resonances has been studied as a function of buffer-gas pressure, of alkali-metal vapor pressure, of detuning from the ${D}_{1}$ and ${D}_{2}$ Na resonances, and of the intensity of the incident light beams. Saturation phenomena and power broadening are observed. The results are explained theoretically in terms of transversely pumped optical gratings. The equivalence of this description with collision-induced coherence gratings in the limit of low light intensities is demonstrated.
The anatomical and functional benefit of bevacizumab in the treatment of macular edema associated with Purtscher-like retinopathy.

The anatomical and functional benefit of bevacizumab in the treatment of macular edema associated with Purtscher-like retinopathy
Parallel determination of phenotypic cytotoxicity with a micropattern of mutant cell lines.

This work presents a novel tool, the Continuous Flow Microspotter (CFM) and its use in patterning cellular microarrays of multiple cell types into the bottom of a tissue culture well. The CFM uses a system of isolated microfluidic channels to make an array of localized microspots of adhesion dependent cells in the bottom of a conventional tissue culture well. With this device we have created micropatterns of multiple cell lines in a single tissue culture well and used this system to conduct simultaneous cytotoxicity tests and recover dose survival curves in a parallel study. This mechanism of parallel testing allows the researcher to employ the use of positive and negative controls, as well as compare the chemical response of phenotypes in a tightly controlled microenvironment. For the experiments presented in this paper we have fabricated a CFM with a set of ten microchannels (five inlet channels and five outlet channels) to pattern a row of five microspots consisting of four cellular microspots and one empty spot for background measurements. Micropatterns containing a set of four different Chinese hamster ovarian cell (CHO) mutant phenotypes were deposited into the bottom of commercially available tissue culture wells then interrogated with mitomycin C, a chemotherapeutic agent. This study shows statistically significant (P < 0.05) hypersensitivity of the UV20 CHO mutant to a DNA interstrand cross-linking agent (mitomycin C). Because the CFM is also capable of depositing proteins and other biomolecules to the individual microspots of the array we foresee capabilities of the 48 microspot CFM to multiplex 48 cell types with 48 chemical reagents all within the confines of a 60 mm2 area.
Boundary integral equations for magnetic screens in ℝ3

A boundary integral method is developed for the scattering of electromagnetic waves at thin obstacles. The exterior boundary value problem for the vector Helmholtz equation with given Neumann data on an open surface piece (screen S) is converted into a system of integral equations for the jumps of the tangential component of the field and its divergence across the screen. A slight modification of the Cauchy data yields a strongly elliptic system of pseudodifferential equations on S which can therefore be used for numerical computations using Galerkin's procedure. The resulting boundary integral equations are analysed using pseudodifferential operator calculus. The principal symbol concept, together with the Wiener–Hopf technique, are used to derive existence and regularity results for the solutions to the boundary integral equations. Quasi-optimal error estimates in the energy norm are given for the numerical scheme.
Carbon isotope composition of low molecular weight hydrocarbons and monocarboxylic acids from Murchison meteorite

Carbon isotopic compositions have been measured for individual hydrocarbons and monocarboxylic acids from the Murchison meteorite, a C2 carbonaceous chondrite which fell in Australia in 1969. With few exceptions, notably benzene, the volatile products are substantially isotopically heavier than their terrestrial counterparts, signifying their extraterrestrial origin. For both classes of compounds, the ratio of C-13 to C-12 decreases with increasing carbon number in a roughly parallel manner, and each carboxylic acid exhibits a higher isotopic ratio than the hydrocarbon containing the same number of carbon atoms. These trends are consistent with the kinetically controlled synthesis of higher homologues from lower ones. The results suggest the possibility that the production mechanisms for hydrocarbons and carboxylic acids may be similar, and impose constraints on the identity of the reactant species.
Attenuation of Apoptosis Underlies B Lymphocyte Stimulator Enhancement of Humoral Immune Response

B lymphocyte stimulator (BLyS) is a newly identified monocyte-specific TNF family cytokine. It has been implicated in the development of autoimmunity, and functions as a potent costimulator with antiimmunoglobulin M in B cell proliferation in vitro. Here we demonstrate that BLyS prominently enhances the humoral responses to both T cell–independent and T cell–dependent antigens, primarily by attenuation of apoptosis as evidenced by the prolonged survival of antigen-activated B cells in vivo and in vitro. BLyS acts on primary splenic B cells autonomously, and directly cooperates with CD40 ligand (CD40L) in B cell activation in vitro by protecting replicating B cells from apoptosis. Moreover, although BLyS alone cannot activate the cell cycle, it is sufficient to prolong the survival of naive resting B cells in vitro. Attenuation of apoptosis by BLyS correlates with changes in the ratios between Bcl-2 family proteins in favor of cell survival, predominantly by reducing the proapoptotic Bak and increasing its prosurvival partners, Bcl-2 and Bcl-xL. In either resting or CD40L-activated B cells, the NF-κB transcription factors RelB and p50 are specifically activated, suggesting that they may mediate BLyS signals for B cell survival. Together, these results provide direct evidence for BLyS enhancement of both T cell–independent and T cell–dependent humoral immune responses, and imply a role for BLyS in the conservation of the B cell repertoire. The ability of BLyS to increase B cell survival indiscriminately, at either a resting or activated state, and to cooperate with CD40L, further suggests that attenuation of apoptosis underlies BLyS enhancement of polyclonal autoimmunity as well as the physiologic humoral immune response.
GABAB receptors modulate synaptically-evoked responses in the rat dentate gyrus, in vivo.

Abstract We assessed the effects of systemically injected baclofen, a GABA B agonist, on single and paired-pulse responses in the dentate gyrus of urethane-anesthetized rats, in vivo. Baclofen (10 mg/kg) significantly increased the duration of single excitatory responses. This increase was blocked by the GABA B receptor antagonist, CGP 35348, indicating that baclofen was acting through GABA B receptors. To determine the mechanism underlying this increase in response duration, the NMDA antagonist, d -2-amino-5-phosphonopentanoic acid ( d -APV), was administered intracerebroventricularly (i.c.v.) after baclofen. d -APV by itself had no effect on the duration of the population excitatory post-synaptic potential (EPSP). However, when infused after baclofen, d -APV blocked the baclofen induced increase in EPSP duration. This indicates the prolonged EPSP duration caused by baclofen resulted from an enhancement of an NMDA receptor mediated component of the response. We then examined the effect of baclofen on population responses to paired stimuli. Baclofen attenuated paired-pulse inhibition of population spike amplitudes at a 25 ms interstimulus interval. CGP-35348 reduced the effect of baclofen on paired-pulse inhibition, indicating that baclofen suppressed paired-pulse inhibition by acting on GABA B receptors. In contrast to its disinhibitory effect at the 25 ms interval, baclofen had an inhibitory effect on responses evoked at a 150 ms interstimulus interval. Under control conditions, we observed that when stimuli were delivered 150 ms apart, both the EPSP duration and population spike amplitude evoked by the second stimulus were enhanced. Baclofen suppressed this enhancement. We conclude that GABA B receptor activation by baclofen reduces short interval inhibition and this reduction of inhibition leads to an enhanced NMDA-receptor mediated response. We also conclude that by reducing inhibition, baclofen occludes paired-pulse disinhibition found at longer interstimulus intervals. In contrast, CGP-35348 directly blocks paired-pulse disinhibition. Thus, GABA B receptor activation can regulate synaptic inhibition, in turn influencing NMDA receptor activation and synaptic transmission. Thus, pharmacologic manipulation of GABA B receptors may provide a powerful approach for regulating synaptic transmission in the hippocampus.
Effect of prenatal imipramine exposure on development of the postnatal rat heart and brain.

Imipramine (IMI) was administered s.c. at 0, 5, or 10 mg/kg/day to pregnant rats on gestation days 8-20 to assess possible alterations in postnatal heart and brain development. Maternal weight gain was significantly reduced in a dose-response manner, but litter size and pup weight on postnatal day (PND) 1 were unaffected. On PND 1, litters were culled to 10 pups for analysis on PNDs 4/5, 7/8, 14/15, and 21/22. Pup body weight was not affected at any age measured, but heart weight was significantly reduced at 10 mg/kg IMI on PNDs 4/5 and 7/8. Brain weight was increased in a dose-related pattern on PNDs 4/5 and 7/8 and was significantly higher at 5 mg/kg IMI on PND 14/15. No significant effect was observed in heart or brain protein and DNA content or in cardiac beta-adrenergic receptor concentration. Prenatal IMI exposure had no effect on basal cardiac ornithine decarboxylase (ODC), an enzyme associated with growth and development, but basal brain ODC was lower at 5 mg/kg IMI at all ages measured. Cardiac ODC stimulation by insulin was unaffected by prenatal exposure to IMI, but isoproterenol-stimulated ODC was increased on PND 21/22 at 5 mg/kg IMI. In conclusion, the IMI-related changes in several parameters suggest that when maternal IMI treatment is used, alterations in postnatal heart and brain development must be considered as possible outcomes.
Investigation of mask selectivities and diamond etching using microwave plasma-assisted etching

Abstract Diamond etching is characterized using a microwave ECR plasma reactor with regard to etch rate selectivity, surface morphology, and feature size. Etching is performed on diamond substrates using a variety of etch mask materials including aluminum, titanium, gold, silicon dioxide and silicon nitride. The etch feed gases are combinations of oxygen, sulfur hexafluoride and argon. Aluminum masks provided the highest selectivity ratio of diamond etch rate to mask etch rate, both with and without SF6 in the oxygen/argon feedgas. Selectivity was not found to be dependent on mask feature size. Gold masks produced the least degree of micromasking.
Phase I study of alternating doublets of topotecan/carboplatin and paclitaxel/carboplatin in patients with newly diagnosed, advanced ovarian cancer.

Abstract Objective. The aim of this study was to evaluate topotecan with carboplatin in an alternating doublet with carboplatin and paclitaxel in first-line ovarian cancer. Methods. Patients with newly diagnosed stage III/IV ovarian cancer were studied. The maximum tolerated dose (MTD) of topotecan (cycles 1, 3, 5, 7) in an alternating doublet regimen was determined through standard dose escalation in cohorts of three; doses of carboplatin (area under the curve [AUC] 4 to 5) and paclitaxel (175 mg/m 2 , cycles 2, 4, 6, 8) were fixed. Dose-limiting toxicity (DLT) was defined only for cycle 1 as febrile neutropenia, prolonged grade 4 granulocytopenia, grade 4 thrombocytopenia, ≥grade 3 nonhematologic toxicity, or failure to recover in ≤7 days. The use of granulocyte colony-stimulating factor (G-CSF) to permit further dose escalation was also studied. Results. Thirty-seven patients received 142 cycles of topotecan/carboplatin. Hematologic DLTs included grade 4 neutropenia (59 events, 42% of cycles) and thrombocytopenia (32 events, 23% of cycles). Granulocytopenia was generally short-lived, and only 2 cases of febrile neutropenia occurred. The MTD was 1.0 mg/m 2 /day topotecan and carboplatin AUC 4, alternating with 175 mg/m 2 paclitaxel and carboplatin AUC 4. Although G-CSF effectively managed myelosuppression, thrombocytopenia developed in later cycles, limiting further topotecan dose escalation. The median progression-free survival was 20.5 months, and elevated pretreatment CA-125 levels normalized in 29 of 34 (85%) patients. Conclusion. The establishment of a reasonably well-tolerated alternating doublet regimen, coupled with evidence of antitumor activity, provides the basis for further investigation of topotecan in first-line therapy of ovarian cancer. Topotecan (1.0 mg/m 2 daily for 3 days) was chosen for further evaluation in a phase II study.
9:46 Validation of the modified Scoliosis Research Society outcomes instrument (SRS-22) for adult deformity

Abstract Purpose of study: The modified Scoliosis Research Society (MSRS) outcomes instrument (SRS-22) had been validated as an outcomes tool for adolescent idiopathic scoliosis. There is no validated disease-specific outcomes instrument for adult scoliosis. The purpose of this paper is to determine the reliability and validity of the modified Scoliosis Research Society questionnaire for adults with scoliosis. Methods used: Reliability of the modified SRS instrument in adults was tested using Cronbach's alpha test of internal consistency and calculation of test-retest parity. The validity of the modified SRS instrument in adults was determined by criterion validity in the domains of pain, function, self-image, and mental health compared with matched domains in the Short Form (SF)-36. of findings: A total of 146 adults with scoliosis were included (133 female and 13 male). The average age was 47.1 years (range, 18 to 86 years). Cronbach's alpha analysis of internal consistency within each domain demonstrates intercorrelation values (μ) greater than 0.75 for each domain of the MSRS. Pearson correlation coefficients with comparable domains within the SF-36 demonstrate high correlation in domains representing pain (r=0.8), function (r=0.85), mental health (r=0.89) and self-image (r=0.63). Total score correlates highly with every domain of the SF-36 (r=0.6 to 0.8). Test-retest analysis in 36 patients who completed questionnaires at both time points demonstrated high correlations for each domain (r=0.83 to 0.94). A floor effect was seen in less than 2% of patients in each domain of the MSRS. A ceiling effect was seen in less than 10% of patients in each domain of the MSRS. Relationship between findings and existing knowledge: Adult spinal deformity is significantly different from adolescent deformity in that affected patients characteristically present with pain and limitation of function. The MSRS questionnaire is a reliable instrument in adults, as demonstrated by a high degree of internal consistency and reproducibility. In adults with scoliosis, the MSRS questionnaire correlated highly with the SF-36 standard. In adolescent deformity, the purpose of surgical intervention is usually to prevent future consequences of progressive deformity. Therefore, the MSRS instrument may underestimate the value of surgery to the adolescent. The application of a disease-specific outcomes instrument to adults with deformity will permit standardization of outcomes assessment in adult deformity surgery. Overall significance of findings: The MSRS is a valid, reliable and reproducible outcomes instrument for adult deformity. This study supports the use of the MSRS questionnaire in the adult spinal deformity population. Disclosures: No disclosure. Conflict of interest: No conflicts.
Experimental study of Lagrangian turbulence in a Stokes flow

Experimental studies are made of chaotic particle motion in a simple Stokes flow system. Surfaces-of-section that exhibit a generic mixture of regular and chaotic particle motions in good agreement with computer simulations are constructed experimentally. Deformations of line elements exhibit \`whorl' and \`tendril' structures of great complexity that can be correlated directly with the underlying particle dynamics and that agree well with numerical computations. In some cases, the laboratory studies are able to resolve dynamical features more accurately than the computer studies. Experiments demonstrating that the flows exhibit poor time reversal in regimes of chaotic particle motion are also performed.
Comparison of metal oxide catalysts for pyrolytic MOLI–MS bacterial identification

Abstract Six metal oxide catalysts were investigated for effective cleavage and laser ionization of bacterial cell wall phospholipid extracts. Calcium oxide has been utilized in the past for this application, but suffered from degradation of catalytic activity. Following evaluation of the six catalysts, CeO2 was found to be the most stable over time and produced fatty acid profiles of bacterial pathogens similar to freshly activated CaO. A suite of ten bacteria previously studied using CaO catalysis provided cross validation results of analysis of 97% correct correlation for negative-ion data. Cerium oxide catalysis studies yielded cross validation results of 100%. Using analysis of variance–principal component analysis (ANOVA–PCA), four sample sets collected with stored catalyst at 0, 8, 24, and 504 h showed no effect based on long-term catalyst degradation. Supervised learning by a fuzzy rule-building expert system (FuRES) that was validated with training and prediction set partitions independent of CeO2 age and unsupervised data analysis using a dendrogram of Euclidean distance confirmed that the CeO2 catalyst age had no effect on the fatty acid mass spectral profiles.
Diaphragmatic breathing maneuvers and movement of the diaphragm after cholecystectomy

Coached efforts at diaphragmatic breathing were assessed as a means of increasing diaphragmatic movement in postoperative patients. Inductive plethysmography was used to measure compartmental tidal volumes of the abdomen (Vab) and the chest (Vc) in eight women (aged 41 ± 16 years) who had no history of cardiovascular or pulmonary disease. These patients were studied before and after (POD1,3) elective cholecystectomy. In preoperative studies, DB increased the supine value of Vab. The corresponding increase on POD1 represents a similar proportion of the resting value. The postoperative fall in resting and stimulated values of Vab is attributed to the known effects of abdominal surgery on diaphragmatic movement. Hence, DB warrants investigation as a method of prophylaxis against the pulmonary complications of surgery, because diaphragmatic movement is largely responsible for ventilation of the lower lung fields, where atelectasis and infection occur most often.
Pulmonary Artery Pseudoaneurysm After Tube Thoracostomy

Pulmonary artery pseudoaneurysm has been described as a complication of Swan-Ganz catheterization and right heart catheterization. Isolated cases of this condition occurring in blunt and penetrating chest trauma have been reported. In this communication, we describe the case of a patient with intracranial hemorrhage who required positive-pressure ventilation and in whom subsequent pneumothorax developed, necessitating tube thoracostomy. A persistent opacification of the lung field resulted in evaluation with computed chest tomography and color-flow Doppler ultrasonography. A pseudoaneurysm of the lingular segmental artery was identified and successfully obliterated by Gelfoam coil embolization.
Mutation in loop I of VP1 of Theiler's virus delays viral RNA release into cells and enhances antibody-mediated neutralization: a mechanism for the failure of persistence by the mutant virus.

The DA strain of Theiler’s murine encephalomyelitis viruses (TMEV) causes a central nervous system (CNS) demyelinating disease with viral persistence despite the presence of high serum anti-TMEV antibody titers. The DA virus mutant, T81D, was created to have a mutation at position 81 in loop I of VP1, close to the putative virus receptor binding site. T81D showed slower replication in vitro and in vivo. T81D-infected mice developed anti-TMEV antibody responses with no virus persistence. We tested whether the differences between the viruses were due to alteration in virus-cell interactions, or in the resistance to neutralization by anti-TMEV antibody. Using radiolabeled viruses, we found no difference in binding to permissive cell lines between the mutant and wild-type viruses. In a semipermissive cell line, DA virus bound more efficiently than T81D. During the uncoating step, both viruses decapsidated without the production of stable intermediates and 80% of viruses were eluted or decapsidated after 45 minutes. At the final step of uncoating, however, T81D showed a slower rate of RNA release than DA virus into cells using a photoinactivation assay. Anti-TMEV monoclonal and polyclonal antibodies neutralized T81D virus more efficiently than DA virus in suspension. Further, these anti-TMEV antibodies were able to neutralize viruses that had already attached to cells but not internalized (postadsorption neutralization [PAN]). However, DA virus showed significant resistance to PAN after cells were incubated at 37°C compared with T81D-infected cells. The development of resistance to PAN appeared to correlate with the rate of RNA release from virions into cells. In T81D virus infection, the slow RNA release and high susceptibility to neutralization by antibodies would result in a failure to establish virus persistence in vivo. Conversely, rapid RNA release and resistance to neutralization could favor virus persistence in DA virus infection.
The conditions of conceptual change in the classroom

The conceptual change model has two major components: the conditions that need to be satisfied for a person to experience conceptual change and the person's conceptual ecology that provides the context in which the conceptual change occurs. A literature review shows that the conditions have been used to analyse interview data and to plan instruction but not to interpret interactions in the classroom. An analysts of the ways in which students can and do produce evidence of meeting conditions shows that this only happens when they are able to monitor and comment on the scientific content of their conceptions. Implications that this conclusion has for classroom teaching are considered.
The phylogeny of archaebacteria

Summary Ribosomal RNA sequence comparisons have been used to refine the phylogenetic relationships among the major groups of archaebacteria. The archaebacteria are shown to comprise two major divisions (“phyla”), the methanogens and their relatives (extreme halophiles and the wall-less species Thermoplasma acidophilum on the one hand, the sulfur-dependent archaebacteria (e.g. the genus Sulfolobus ) on the other. Within the first of these the Methanomicrobiales are shown to be specifically related to the extreme halophiles, to the exclusion of the Methanococcales and the Methanobacteriales . The thermoacidophilic mycoplasma is only peripherally associated with the methanogen-halophile cluster, however.
Mismatch Repair proteins are recruited to replicating DNA through interaction with Proliferating Cell Nuclear Antigen (PCNA)

Mismatch Repair (MMR) is closely linked to DNA replication; however, other than the role of the replicative sliding clamp (PCNA) in various MMR functions, the linkage between DNA replication and MMR has been difficult to investigate. Here we use an in vitro DNA replication system based on simian virus 40, to investigate MMR recruitment to replicating DNA. Both DNA replication and MMR proteins are recruited to replicating DNA in an origin-dependent fashion. Primer synthesis is required for recruitment of both PCNA and MMR proteins, but not for recruitment of the single-stranded DNA-binding protein (RPA). Blocking PCNA recruitment to replicating DNA with a p21-based polypeptide blocks PCNA and MMR, but not RPA recruitment. Once PCNA and subsequent proteins required for replication are loaded onto DNA, addition of p21 leaves PCNA on the replicating DNA, but actively displaces MMR proteins. These findings indicate that the MMR machinery is recruited to replicating DNA through its interaction with PCNA, and suggests that this occurs via binding of the MMR proteins to the multi-protein interaction sites on PCNA. These studies demonstrate the utility of this system for further investigation of the role of DNA replication in MMR.
Symmetry properties of spin-polarized leed

Abstract The transformational properties of the polarizing power P and the analyzing power S of a polarized LEED beam under time reversal, rotations and reflections are derived. A general relationship between S and P is given, and special cases of equality are noted.
Decay of194Os andL 1 subshell yields atZ=77

The relative intensities of x rays and gammas emitted in the beta decay of194Os are measured. No evidence for the feeding of a level at 83 keV in194Ir is found. An upper limit of 1.7×10−4 was set for theK shell internal ionization probability in the beta decay to the ground state of194Ir. TheL-conversion coefficient of 43 keV transition is found to be 12.1 and the transition is mainly ofM1 type with an admixture of 1.3%E2 type. TheL1 subshell yields atZ=77 are determined to beω1=0.16±0.04,f12=0.11±0.04 andf13=0.37±0.03.
Cross-Validation of Two Measures for Assessing Feigned Mental Incompetence in Male Prison Inmates

A pair of two-alternative forced-choice tests—one concerning general knowledge and the other concerning moral reasoning—were administered to male prison inmates who were assigned randomly to one of three experimental conditions: control, naive faking, and coached faking. The majority of inmates in the naive and coached faking conditions scored significantly below chance on at least one of the tests. No one in the control condition scored below chance on either test. When a cutoff score suggested by a previous study was used as the classification criterion, sensitivity increased modestly, but there was a corresponding decrease in specificity. First-time offenders did not differ significantly from inmates with previous prison terms. The data cross-validate the two tests as means of identifying individuals who are feigning a lack of mental competence.
Leadership for Undergraduate STEM Reform: Weaving a Communal Web

Successful reform of undergraduate science, technology, engineering, and mathematics (STEM) education requires good leaders; therefore, leadership development will be key if the national calls for reform (e.g., Vision and Change) are to be answered. The Partnership for Life Sciences Education (PULSE) is focused on whole-department reform, which will require recruiting and supporting grassroots reformers who lead their colleagues through the change process. Department leaders will require (a) support networks that extend within and beyond each institution, (b) development of leadership skills and competencies, and (c) a mutually agreed-upon strategic plan that inspires all to action. The STEM Department Evaluation Rubric is presented here as a tool to help establish that shared vision. Successful leaders will also need resilience, good humor and moral imagination, because the challenges are many but the rewards are substantial and sit at the core of the mission of our institutions.
COOPERATION OF P53 LOSS OF FUNCTION AND V-HA-RAS IN TRANSFORMATION OF MOUSE KERATINOCYTE CELL LINES

We previously demonstrated that after transduction with the v-Ha-ras oncogene and grafting onto nude mouse hosts, primary epidermal keratinocytes with a null mutation in the p53 gene form tumors with increased growth rates and predisposition to malignant conversion relative to p53 wild-type keratinocytes (Weinberg WC, et al., Cancer Res 54:5584–5592, 1994). To further explore the cooperation between p53 loss of function and activation of the ras oncogene, cell lines were established from the normal epidermises of newborn and adult p53-null mice, and parallel subclones were reconstituted with the p53val135 temperature-sensitive mutant. Reconstituted lines C, G, N, and V demonstrated functional p53 transcriptional activator activity at the wild-type–permissive temperature of 32°C, compared with the hygromycin-selected control line X and parental p53-null lines NHK4 and AK1b. Hygromycin-selected subclones, but not the parental lines, made normal skin in vivo; all cell lines made carcinomas after introduction of v-Ha-ras, independent of p53 status. These cell lines were compared in vitro at 32°C to maximize the amount of p53val135 in the wild-type conformation. Expression of v-Ha-ras did not consistently alter p53-mediated transcriptional activity, suggesting that ras acts downstream or independently of p53. No correlation was observed between p53-mediated transcriptional activity and in vitro growth rates, colony formation after exposure to ultraviolet light, or suppression by normal neighboring keratinocytes. However, keratinocyte cell lines devoid of p53 and expressing v-Ha-ras formed colonies in soft agar; this was blocked at 32°C in all cell lines reconstituted with p53val135. These keratinocyte lines provide a model for exploring the role of p53 and the interaction of p53 and ras in keratinocyte transformation. Mol. Carcinog. 21:50–61, 1998. © 1998 Wiley-Liss, Inc.