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At BESSY II, two new beamlines for RIXS and for X-Ray-microscopy need a short period variably polarizing undulator. For this purpose, the first in-vacuum APPLE II undulator worldwide is under construction. The parameters are as follows: period length λ 0 = 32 mm, # periods = 78, minimum gap = 7mm. The design incorporates a force compensation scheme as proposed by two of the authors at the SRI 2018. All precision parts of the drive chain are located in air. New transverse slides for the transversal slit adjustment have been developed and tested. Optical Micrometers measure the gap and phase positions, similar to the system of the CPMU17 at BESSY II. They provide the signals for motor feedback loops. A new UHV-compatible soldering technique, as developed with industry, relaxes fabrication tolerances of magnets and magnet holders and simplifies the magnet assembly. A 10-period prototype has been setup for lifetime tests of the new magnetic keeper design. The paper summarizes the status of the undulator IVUE32.

Despite the known importance of the endoplasmic reticulum (ER) in protein synthesis and vesicular transport, it is not clear whether neuropeptide and neuromodulator oxytocin can directly affect components of the ER in neuronal cells. Therefore, in the present study, we hypothesize that incubation of hippocampal neuronal cells in a presence of oxytocin 1) plays a role in the regulation of the expression of selected ER chaperone components and molecules involved in unfolded protein response pathway 2) affects distribution of the intracellular fluorescence signal highly selective for the ER. We found that oxytocin (1 μM) after 60 min significantly decreased the gene expression of oxidoreductase Ero1β, chaperone glucose-regulated proteins (Grp) 78 and Grp94. A significant decrease in GRP78 protein levels in response to oxytocin treatment occurred after 30, 60 and 120 min. We also observed a time-dependent increase in calreticulin protein levels with a statistically significant increase observed after 360 min. We found that the dynamics of the ER network changes significantly within 2 h of incubation under the influence of oxytocin. In conclusion we have shown that ER chaperones, oxidoreductases and trafficking molecules in neuronal cells are changing in response to oxytocin treatment in a short-term scenario potentially relevant for growth of dendrites and axons.

The human gut can be considered an ecosystem comprised of a community of microbes and nonliving components such as food metabolites and food additives. Chronic diseases are increasingly associated with disruption of this ecosystem. The science of restoration ecology was developed to restore degraded ecosystems, but its principles have not been applied widely to gut medicine, including the treatment of inflammatory bowel disease (IBD). One principle of ecological restoration is that ‘passive’ restoration, which involves removing an ecosystem disturbance, should occur before attempting additional ‘active’ interventions. We discuss evidence that poor diet is principle source of disturbance in IBD, and therefore requires better attention in its research and clinical care. Another restoration principle is that higher biodiversity may improve ecosystem behavior, but this idea has not been tested for its possible importance in donor stool during fecal microbiota transplants. Lay summary: In patients with chronic disease the gut microbiome behaves like a disturbed ecosystem. Principles borrowed from the science of restoration ecology identify a need to better understand the influence of diet on treatment of inflammatory bowel disease and the importance of donor diversity in fecal microbiota transplants.

We present the first simultaneous photometric and spectroscopic investigation of a large set of RR Lyrae variables in a globular cluster. The radial-velocity data presented comprise the largest sample of RVs of RR Lyrae stars ever obtained. The target is M3; $BVI_{\mathrm{C}}$ time-series of 111 and $b$ flux data of further 64 RRab stars, and RV data of 79 RR Lyrae stars are published. Blazhko modulation of the light curves of 47 percent of the RRab stars are detected. The mean value of the center-of-mass velocities of RR Lyrae stars is $-146.8$ km s$^{-1}$ with 4.52 km s$^{-1}$ standard deviation, which is in good agreement with the results obtained for the red giants of the cluster. The ${\Phi_{21}}^{\mathrm RV}$ phase difference of the RV curves of RRab stars is found to be uniformly constant both for the M3 and for Galactic field RRab stars; no period or metallicity dependence of the ${\Phi_{21}}^{\mathrm RV}$ is detected. The Baade-Wesselink distances of 26 non-Blazhko variables with the best phase-coverage radial-velocity curves are determined; the corresponding distance of the cluster, $10480\pm210$ pc, agrees with the previous literature information. A quadratic formula for the $A_{\mathrm{puls}}-A_V$ relation of RRab stars is given, which is valid for both OoI and OoII variables. We also show that the $(V-I)_0$ of RRab stars measured at light minimum is period dependent, there is at least 0.1 mag difference between the colours at minimum light of the shortest- and longest-period variables., Comment: 22 pages, 14 figures, accepted for publication in the Monthly Notices of the Royal Astronomical Society

Background Current devices for hemostasis in flexible endoscopy are inferior to methods used during open or laparoscopic surgery and might be ineffective for natural orifice transluminal endoscopic surgery. Objective To compare new flexible bipolar forceps (FBF), designed principally for natural orifice transluminal endoscopic surgery, with laparoscopic bipolar forceps (LBF) for hemostasis of intra-abdominal porcine arteries. Setting Surgical laboratories in Europe and the United States. Design and Interventions New FBF for hemostasis (3.7-mm diameter), featuring electrode isolation, were compared with rigid 5-mm LBF (ERBE BiClamp LAP forceps) at recommended settings. A porcine model of acute hemostasis was prepared by suturing the uterine horns and cecum to the abdominal wall, exposing uterine arteries, ovarian pedicles, cecal mesenteric bundles, and the inferior mesenteric artery. This allowed access to 10 vessels in each pig by transabdominal laparoscopic devices or a transgastric double-channel gastroscope. Vessels were measured, coagulated at 4 and more points, and transected. Blood pressure was increased to more than 200 mm Hg for 10 minutes by administering phenylephrine. Delayed bleeding was identified. Main Outcome Measurements In 7 pigs, a total of 65 vessels (1.5-6.0 mm) were randomly allocated to FBF (n = 32) or LBF (n = 33). Successful hemostasis both before and after blood pressure increase was equivalent between the 2 groups (before: 88% FBF vs 88% LBF, not significant [NS]; after: 97% FBF vs 94% LBF, NS). With FBF, the number of seals per vessel was 4.8 vs 4.4 with LBF (NS). The energy used to create FBF seals was 19.8 J vs 38.2 J for LBF ( P Limitations Results from porcine studies may not reflect patient outcomes. Conclusions In a porcine model, transgastric FBF endoscopic hemostasis was as effective as conventional laparoscopic hemostasis using LBF across a wide range of vessels.

The overtone and multi-mode RR Lyrae stars in the globular cluster M3 are studied using a 200-d long, $B,V$ and $I_{\mathrm C}$ time-series photometry obtained in 2012. 70\% of the 52 overtone variables observed show some kind of multi-periodicity (additional frequency at ${f_{0.61}}={f_{\mathrm {1O}}}/0.61$ frequency ratio, Blazhko effect, double/multi-mode pulsation, period doubling). A signal at 0.587 frequency ratio to the fundamental-mode frequency is detected in the double-mode star, V13, which may be identified as the second radial overtone mode. If this mode-identification is correct, than V13 is the first RR Lyrae star showing triple-mode pulsation of the first three radial modes. Either the Blazhko effect or the ${f_{0.61}}$ frequency (or both of these phenomena) appear in 7 double-mode stars. The $P_{\mathrm{1O}}/P_{\mathrm{F}}$ period ratio of RRd stars showing the Blazhko effect are anomalous. A displacement of the main frequency component at the fundamental-mode with the value of modulation frequency (or its half) is detected in three Blazhko RRd stars parallel with the appearance of the overtone-mode pulsation. The ${f_{0.61}}$ frequency appears in RRc stars that lie at the blue side of the double-mode region and in RRd stars, raising the suspicion that its occurrence may be connected to double-mode pulsation. The changes of the Blazhko and double-mode properties of the stars are also reviewed using the recent and archive photometric data., accepted for publication in ApJ Suppl. 26 pages, 25 figures

A stress-wave force balance for measurement of thrust, lift, and pitching moment on a large scramjet model (40 kg in mass, 1.165 in in length) in a reflected shock tunnel has been designed, calibrated, and tested. Transient finite element analysis was used to model the performance of the balance. This modeling indicates that good decoupling of signals and low sensitivity of the balance to the distribution of. the load can be achieved with a three-bar balance. The balance was constructed and calibrated by applying a series of point loads to the model. A good comparison between finite element analysis and experimental results was obtained with finite element analysis aiding in the interpretation of some experimental results. Force measurements were made in a shock tunnel both with and without fuel injection, and measurements were compared with predictions using simple models of the scramjet and combustion. Results indicate that the balance is capable of resolving lift, thrust, and pitching moments with and without combustion. However vibrations associated with tunnel operation interfered with the signals indicating the importance of vibration isolation for accurate measurements.

A shock-free expansion tunnel nozzle has been designed for the NASA HYPULSE facility at GASL. The main purpose of the nozzle is to increase the available test core size to accommodate a large-scale model, with the initial design intended for aeroheating studies at re-entry flow conditions. The nozzle was designed to expand the hypervelocity flow at the acceleration tube exit to a larger test core size of 30 cm, while maintaining a unit Reynolds number of at least 9.8 x 105/m. The two main challenges encountered in the design were the high entrance Mach number and the thick incoming tube-wall boundary layer. The paper discusses the design strategies of using a contour obtained using the method-of-characteristics as opposed to the conical geometry, and the skimmer versus the full-capture approaches, to achieve shock-free uniform exit flow with acceptable Reynolds numbers. To fully characterize the final design, computational fluid dynamics analyses were carried out using the nonuniform viscous flow profile at the acceleration tube exit as a start-line condition. The pitot pressure distribution at nozzle exit, as well as the heat flux on a hemisphere placed at nozzle exit, were calculated and compared with experiments. Besides discussing the fluid dynamic aspects of the design, a short description of a cost-effective manufacturing technique of fabricating the nozzle from fiberglass is also included.

A computational study has been carried out to examine the effects of driver gas contamination in the NASA HYPULSE facility at GASL when operating with a detonation driver in reflected-shock tunnel mode. Unlike high-enthalpy shock tunnels which use helium as a driver gas, the driver gas in a detonation driver consists of a mixture of water vapour and argon, which has very different chemical and thermodynamic properties than those of helium. The purpose of the present work is to quantitatively evaluate the effects of driver gas contamination on the flow properties in the test section. Two computational analyses have been performed. The first analysis examined the nozzle flow under the influence of a prescribed level of driver gas contamination. In the second analysis, the transient development of the driver gas leakage in the reflected-shock region in the shock tube is studied. The unique flow features brought about by the detonation-driver gas and the method for detecting the contamination are discussed.

The absence of stellar disc truncations in low-inclined spiral galaxies has been a matter of debate in the last decade. Disc truncations are often observed in highly inclined galaxies but no obvious detection of this feature has so far been made in face-on spirals. Here we show, using a simple exponential disc plus stellar halo model based on current observational constraints, that truncations in face-on projections occur at surface brightness levels comparable to the brightness of stellar haloes at the same radial distance. In this sense, stellar haloes outshine the galaxy disc at the expected position of the truncations, forcing their studies only in highly inclined (edge-on) orientations., 6 pages, 2 figures. Submitted to MNRAS. Comments are welcome

Brain development is determined by neuronal differentiation including changes of cell polarity and asymetric growth of neuronal processes. Although, there are many unkown factors contributing to changes of lenght of neuronal cones, mounting experimental and review papers focus on changes of growth conus and role of axonal transport. In particular, mechanisms of actin/microtubule polymerisation and depolymerisation are important. Role of intracellular calcium is also significant. Normal and properly timed changes of lenght of axons and dendrites are dependent on interaction of neurons and glia. Moreover, regeneration of injured axons is dependent on growth factors secreted from glial cells. The aim of the present study is characterisation of the most important mechanisms underlying changes of lenght of neurites.

The operating space of the TCV tokamak has been extended to higher elongation, kappa = 2.8, and higher normalized current, I-N = I-p/aB = 3.6MA/mT, than were previously attainable. This has been achieved by optimizing the parameters of the vertical position control system and by optimizing the plasma shape. Experimental current and beta limits were found to be consistent with ideal MHD stability calculations, using measured plasma shapes and profiles. The sawtooth period was measured as a function of elongation and sawtooth oscillations are found to disappear, at high elongation, when the internal inductance drops below l(i) similar to 0.69. MHD events at high elongation have been analysed, using magnetic fluctuation measurements. The electron energy confinement time at high elongation, 2.2 < kappa < 2.7, shows a strong dependence on density and power flux through the plasma surface, but no statistically significant dependence on K. Finally, we have applied off-axis, second harmonic, X-mode electron cyclotron resonance heating (ECRH) in order to flatten the current profile and improve vertical stability. This gave access to previously inaccessible domains in kappa-IN space.

To study the nature of steric and electronic effects of diphosphites, a novel diphosphite was synthesized and tested with regard of its catalytic performance in the hydroformylation of styrene catalyzed by platinum complexes. The novel ligand 3 was prepared by the reaction of enantiomerically pure pentane-2,4-diol with (S)-2-chloro-5,5',6,6',7,7',8,8'-octahydro-dinaphtho[2,1-d:1',2'-f][1,3,2]dioxaphosphepine based on H8-BINOL (H8-BINOL = 5,5',6,6',7,7',8,8'-octahydro-1,1'-bi-2-naphthol). For a comparative study, the BINOL (1,1'-bi-2-naphthol) based analogue 4 of 3 has also been synthesized. The highest chemoselectivity to aldehyde (71%) and regioselectivity to branched aldehyde (85%) with an enantiomer excess (ee) of 86% was obtained with the platinum(II)-SnCl2 catalytic system associated with (2S,4S)-bis(S)-3.Key words: asymmetric hydroformylation, chirality, homogeneous catalysis, P ligands, platinum.

Cyclic and bicyclic sulfates have been prepared from commonly available alcohols. Nucleophilic cleavage of the cyclic sulfates affords a new type of water-soluble mono- and ditertiary phophines bearing -OSO3Li groups in distinguished positions in the molecular framework. Both phosphines have amphiphilic character. Reactions of the chiral 2 and the dppp analogue 5 with [Rh(COD)Cl]2 and Pt(PhCN)2Cl2 provide novel zwitterionic complexes. Rhodium complexes of 2 and 5 have been successfully applied in liquid biphasic hydroformylation of styrene and octene-1. When the rhodium complex of 5 was used as catalyst in hydroformylation of styrene, less then 4 ppm rhodium could be detected in the organic phase.Key words: cyclic sulfates, water soluble phosphines, amphiphilic character, Rh complexes, Pt complexes, hydroformylation.

Irreversible electroporation (IRE) has been shown to be an effective method of killing cells locally. In contrast to radiofrequency ablation, the mechanism by which cells are thought to die via IRE is the creation of pores in cell membranes, without substantial increase in tissue temperature. To determine the degree to which cell death is non-thermal, we evaluated IRE in porcine hepatocytes in vivo. Using pulse widths of 10μs, bursts of 3 kV square-wave pulses were applied through a custom probe to the liver of an anesthetized pig. Affected tissue was evaluated histologically via stainings of hematoxylin & eosin (H&E), nitroblue tetrazolium (NBT) to monitor cell respiration and TUNEL to gauge apoptosis. Temperature was measured during the application of electroporation, and heat transfer was modeled via finite element analysis. Cell death was calculated via Arrhenius kinetics. Four distinct zones were observed within the ring return electrode; heat-fixed tissue, coagulation, necrotic, and viable. The Arrhenius damage integral estimated complete cell death only in the first zone, where the temperature exceeded 70°C, and partial or no cell death in the other zones, where maximum temperature was approximately 45°C. Except for a limited area near the electrode tip, cell death in IRE is predominantly due to a non-thermal mechanism.

Husemann, B. et. al., We present the first public data release (DR1) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. It consists of science-grade optical datacubes for the first 100 of eventually 600 nearby (0.005 < z < 0.03) galaxies, obtained with the integral-field spectrograph PMAS/PPak mounted on the 3.5 m telescope at the Calar Alto observatory. The galaxies in DR1 already cover a wide range of properties in color-magnitude space, morphological type, stellar mass, and gas ionization conditions. This offers the potential to tackle a variety of open questions in galaxy evolution using spatially resolved spectroscopy. Two different spectral setups are available for each galaxy, (i) a low-resolution V500 setup covering the nominal wavelength range 3745-7500 Å with a spectral resolution of 6.0 Å (FWHM), and (ii) a medium-resolution V1200 setup covering the nominal wavelength range 3650-4840 Å with a spectral resolution of 2.3 Å (FWHM). We present the characteristics and data structure of the CALIFA datasets that should be taken into account for scientific exploitation of the data, in particular the effects of vignetting, bad pixels and spatially correlated noise. The data quality test for all 100 galaxies showed that we reach a median limiting continuum sensitivity of 1.0 × 10-18 erg s-1 cm-2 Å-1 arcsec-2 at 5635 Å and 2.2 × 10 -18 erg s-1 cm-2 Å-1 arcsec-2 at 4500 Å for the V500 and V1200 setup respectively, which corresponds to limiting r and g band surface brightnesses of 23.6 mag arcsec-2 and 23.4 mag arcsec-2, or an unresolved emission-line flux detection limit of roughly 1 × 10-17 erg s-1 cm-2 arcsec-2 and 0.6 × 10 -17 erg s-1 cm-2 arcsec-2, respectively. The median spatial resolution is 3-7, and the absolute spectrophotometric calibration is better than 15% (1σ). We also describe the available interfaces and tools that allow easy access to this first publicCALIFA data at http://califa.caha.es/DR1. © 2013 ESO.

Some classical genetic methods such as mass selection or family selection used to improve the productivity of common carp have produced poor results, hybridisation experiments were carried out based on the crossbreeding of different genotypes. The crossing experiments used different strains of cultivated common carp maintained in the live gene bank of the Fish Culture Research Institute, Szarvas. Since 1965 more than 100 crossing combinations have been tested under different production conditions. For the most important quantitative characteristics such as survival, growth, feed conversion, slaughter value and quality of meat three outstanding hybrids had been identified. The Szarvas 215 mirror, the Szarvas P.31 scaly and the Szarvas P.34 scaly hybrids showed 20–25% higher productivity than the traditional races of common carp.

Acknowledgements. We thank the referee Eric Emsellem for his detailed comments which helped to improve the content and presentation of the article. We thank the director of CEFCA, Dr. M. Moles, for his sincere support to this project. We thank the Viabilidad, Diseno, Acceso y Mejora funding program, ICTS-2009-10, and the Plan Nacional de Investigación y Desarrollo funding program, AYA2010-22111-C03-03, of the Spanish Ministerio de Ciencia e Innovacion, for the support given to this project. I.M. and J.M. acknowledge financial support from the Spanish grant AYA2010-15169 and Junta de Andalucía TIC114 and Excellence Project P08-TIC-03531. C.K., as a Humboldt Fellow, acknowledges support from the Alexander von Humboldt Foundation, Germany. B. Jungwiert acknowledges support by the grants AV0Z10030501 (Academy of Sciences of the Czech Republic) and LC06014 (Center for Theoretical Astrophysics, Czech Ministry of Education). T. Bartáková acknowledges support by the grants No. 205/08/H005 (Czech Science Foundation) and MUNI/A/0968/2009 (Masaryk University in Brno). Polychronis Papaderos is supported by a Ciencia 2008 contract, funded by FCT/MCTES (Portugal) and POPH/FSE (EC). This paper makes use of the Sloan Digital Sky Survey data. Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the U.S. Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. The SDSS Web Site is http://www.sdss.org/. The SDSS is managed by the Astrophysical Research Consortium for the Participating Institutions. The Participating Institutions are the American Museum of Natural History, Astrophysical Institute Potsdam, University of Basel, University of Cambridge, Case Western Reserve University, University of Chicago, Drexel University, Fermilab, the Institute for Advanced Study, the Japan Participation Group, Johns Hopkins University, the Joint Institute for Nuclear Astrophysics, the Kavli Institute for Particle Astrophysics and Cosmology, the Korean Scientist Group, the Chinese Academy of Sciences (LAMOST), Los Alamos National Laboratory, the Max-PlanckInstitute for Astronomy (MPIA), the Max-Planck-Institute for Astrophysics (MPA), New Mexico State University, Ohio State University, University of Pittsburgh, University of Portsmouth, Princeton University, the United States Naval Observatory, and the University of Washington., The final product of galaxy evolution through cosmic time is the population of galaxies in the local universe. These galaxies are also those that can be studied in most detail, thus providing a stringent benchmark for our understanding of galaxy evolution. Through the huge success of spectroscopic single-fiber, statistical surveys of the Local Universe in the last decade, it has become clear, however, that an authoritative observational description of galaxies will involve measuring their spatially resolved properties over their full optical extent for a statistically significant sample. We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction. We summarize the survey goals and design, including sample selection and observational strategy. We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data. This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of ~600 galaxies in the Local Universe (0.005 < z < 0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK integral field unit (IFU), with a hexagonal field-of-view of ~1.3⎕′, with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 Å, using two overlapping setups (V500 and V1200), with different resolutions: R ~ 850 and R ~ 1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed. The analyzed data fulfillthe expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis: (i) the final datacubes reach a 3σ limiting surface brightness depth of ~23.0 mag/arcsec2 for the V500 grating data (~22.8 mag/arcsec2 for V1200); (ii) about ~70% of the covered field-of-view is above this 3σ limit; (iii) the data have a blue-to-red relative flux calibration within a few percent in most of the wavelength range; (iv) the absolute flux calibration is accurate within ~8%with respect to SDSS; (v) the measured spectral resolution is ~85 km s-1 for V1200 (~150 km s-1 for V500); (vi) the estimated accuracy of the wavelength calibration is ~5 km s-1 for the V1200 data (~10 km s-1 for the V500 data); (vii) the aperture matched CALIFA and SDSS spectra are qualitatively and quantitatively similar. Finally, we show that we are able to carry out all measurements indicated above, recovering the properties of the stellar populations, the ionized gas andthe kinematics of both components. The associated maps illustrate the spatial variation of these parameters across the field, reemphasizing the redshift dependence of single aperture spectroscopic measurements. We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe., CEFCA, Viabilidad, Diseno, Acceso y Mejora ICTS-2009-10, Instituto de Salud Carlos III Spanish Government AYA2010-22111-C03-03, Spanish grant AYA2010-15169, Junta de Andalucia TIC114, Excellence Project P08-TIC-03531, Alexander von Humboldt Foundation, Czech Academy of Sciences AV0Z10030501, Center for Theoretical Astrophysics, Czech Ministry of Education LC06014, Grant Agency of the Czech Republic 205/08/H005, Masaryk University in Brno MUNI/A/0968/2009, Ciencia 2008 contract, Portuguese Foundation for Science and Technology, European Commission Joint Research Centre, European Social Fund (ESF), Alfred P. Sloan Foundation, National Science Foundation (NSF), United States Department of Energy (DOE), National Aeronautics & Space Administration (NASA), Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT), Max Planck Society Foundation CELLEX, Higher Education Funding Council for England, Science & Technology Facilities Council (STFC) ST/H00243X/1 ST/J001538/1 ST/H004912/1

Taking advantage of the ultra-deep near-infrared imaging obtained with the Hubble Space Telescope on the Hubble Ultra Deep Field, we detect and explore for the first time the properties of the stellar haloes of two Milky Way-like galaxies at z~1. We find that the structural properties of those haloes (size and shape) are similar to the ones found in the local universe. However, these high-z stellar haloes are approximately three magnitudes brighter and exhibit bluer colours ((g-r), Comment: 14 pages, 14 figures. Accepted in MNRAS. Replaced to match the published version

Many of the compact extragalactic radio sources that are used as fiducial points to define the celestial reference frame are known to have proper motions detectable with long-term geodetic/astrometric Very Long Baseline Interferometry (VLBI) measurements. These changes can be as high as several hundred micro-arcseconds per year for certain objects. When imaged with VLBI at milli-arcsecond (mas) angular resolution, these sources (radio-loud active galactic nuclei) typically show structures dominated by a compact, often unresolved "core" and a one-sided "jet". The positional instability of compact radio sources is believed to be connected with changes in their brightness distribution structure. For the first time, we test this assumption in a statistical sense on a large sample, not only for individual objects. We investigate a sample of 62 radio sources for which reliable long-term time series of astrometric positions as well as detailed 8-GHz VLBI brightness distribution models are available. We compare the characteristic direction of their extended jet structure and the direction of their apparent proper motion. We present our data and analysis method, and conclude that there is indeed a correlation between the two characteristic directions. However, there are cases where the ~1-10-mas scale VLBI jet directions are significantly misaligned with respect to the apparent proper motion direction., Comment: 14 pages, 3 figures, 1 table. Accepted for publication in the Astronomical Journal

Testing at hypervelocity test conditions continues in the Hypulse expansion tube. A newly-calibrated Mach 13 operating point has been achieved, and hydrogen injection studies were performed at this test condition. The experiments were conducted in a 2-in x 1-in combustor model employing three injector configurations: a single flush-wall circular orifice; two such orifices on opposite walls (the 'dual' injector configuration); and two orifices on the upper and the lower walls (the 'quad' injector configuration). The quad injectors were distinctly superior to the other two configurations in promoting mixing, ignition, and combustion. The single injector, however, proved to be superior to the dual injectors, supporting the concept that the aspect ratio of the 'injection cell' plays a large role in promoting the processes required to achieve high combustion efficiency.

Hydrogen-air mixing and combustion experiments at air velocities approaching 17,000 ft/s have been conducted in the HYPULSE facility expansion tube. The results proved to be repeatable and indicated increasing extent of reaction as the fuel equivalence ratio was increased from one to three. Comparisons were made with the results of a one-dimensional, finite-rate chemistry code and one-dimensional cycle codes that assume equilibrium chemistry. These comparisons indicate that the magnitudes and trends of the measured longitudinal pressure distributions are predicted by the one-dimensional codes provided the relevant physical phenomena are accounted for in the computations.

Few data inform decisions on the optimal bipolar electrocoagulation (BPEC) technique.To assess how technical factors influence energy delivery and coagulation.Prospective, randomized study in experimental models: meat, live pig mesenteric arteries.Standard and prototype BPEC probes were applied at varying durations (2, 10, and 20 seconds), application forces (5, 75, and 150 g), and watt settings (10, 15, and 20 W). BPEC devices were applied to arteries with 40 g versus no additional force.For the meat model: energy delivered, impedance, coagulation and cavitation depth, and coagulation surface area. For the mesenteric arteries: hemostasis.The energy delivered increased with duration and force (P.001) but not with the watt setting. Impedance rose rapidly at higher watt settings (300 ohms within approximately 5 seconds at 20 W and approximately 10 seconds at 15 W), with a coincident drop in power. Coagulation depth and surface area correlated with energy delivered (r = 0.70-0.97). Only duration was associated with the coagulation depth (P.001); cavitation (which occurred with a standard BPEC probe) plus coagulation depth was also associated with application force (P.001). Hemostasis of the mesenteric arteries was achieved only with 40 g of force.The accuracy of these models in predicting clinical results is uncertain.Increasing BPEC duration increased the energy delivered and the coagulation, whereas increasing the watt setting did not because of a rapid rise in impedance. Optimal BPEC technique included a lower watt setting (eg, 15 W), a longer duration (eg, approximately 10-12 seconds), and tamponade of the bleeding site.

We are developing a video see-through head-mounted display (HMD) augmented reality (AR) system for image-guided neurosurgical planning and navigation. The surgeon wears a HMD that presents him with the augmented stereo view. The HMD is custom fitted with two miniature color video cameras that capture a stereo view of the real-world scene. We are concentrating specifically at this point on cranial neurosurgery, so the images will be of the patient's head. A third video camera, operating in the near infrared, is also attached to the HMD and is used for head tracking. The pose (i.e., position and orientation) of the HMD is used to determine where to overlay anatomic structures segmented from preoperative tomographic images (e.g., CT, MR) on the intraoperative video images. Two SGI 540 Visual Workstation computers process the three video streams and render the augmented stereo views for display on the HMD. The AR system operates in real time at 30 frames/sec with a temporal latency of about three frames (100 ms) and zero relative lag between the virtual objects and the real-world scene. For an initial evaluation of the system, we created AR images using a head phantom with actual internal anatomic structures (segmented from CT and MR scans of a patient) realistically positioned inside the phantom. When using shaded renderings, many users had difficulty appreciating overlaid brain structures as being inside the head. When using wire frames, and texture-mapped dot patterns, most users correctly visualized brain anatomy as being internal and could generally appreciate spatial relationships among various objects. The 3D perception of these structures is based on both stereoscopic depth cues and kinetic depth cues, with the user looking at the head phantom from varying positions. The perception of the augmented visualization is natural and convincing. The brain structures appear rigidly anchored in the head, manifesting little or no apparent swimming or jitter. The initial evaluation of the system is encouraging, and we believe that AR visualization might become an important tool for image-guided neurosurgical planning and navigation.

A series of Hyper-X Mach 10 flowpath ground tests are underway to obtain engine performance and operation data and to confirm and refine the flowpath design methods. The model used is a full-scale height, partial-width replica of the Hyper-X Research Vehicle propulsive flowpath with truncated forebody and aftbody. This is the fifth test entry for this model in the NASA-HYPULSE facility at GASL. For this entry the facility nozzle and model forebody were modified to better simulate the engine inflow conditions at the target flight conditions. The forebody was modified to be a wide flat plate with no flow fences, the facility nozzle Mach number was increased, and the model was positioned to be tested in a semi-direct-connect arrangement. This paper presents a review of the test conditions, model calibrations, and a description of steady flow confirmation. The test series included runs using hydrogen fuel, and a silane-in-hydrogen fuel mixture. Other test parameters included the model mounting angle (relative to the tunnel flow), and the test gas oxygen fraction to account for the presence of [NO] in the test gas at the M10 conditions.

The TCV tokamak (R = 0.88 in, a < 0.25 in, BT < 1.54 T) is equipped with six 0.5 MW gyrotron sources operating at 82.7 GHz for second harmonic X mode ECH. By distributing the ECCD current sources over the discharge cross section, fully driven stationary plasmas with I-p = 210 kA, n(e0) = 2 x 10(19) m(-3), T-e0 approximate to 4 keV, were obtained for the full discharge duration of 2 s. Highly peaked electron temperature profiles with T-e0 up to 12 keV were obtained in central counter-current drive scenarios with off-axis ECH. Absorption measurements using a 118 GHz gyrotron have demonstrated the importance of suprathermal electrons for third harmonic absorption. A coupled heat-particle transport phenomenon known as 'density pumpout', which leads to the expulsion of particles from the plasma core, has been linked to the presence of m = I modes, suggesting that it is due to the existence of locally trapped particles associated with the loss of axisymmetry. Highly elongated discharges have been developed with ohmic heating (kappa < 2.8) and off-axis ECH. The latter exhibit considerably improved vertical stability due to current profile broadening. A 'gateway' for ELMy H modes has been discovered, which allows stationary ohmic ELMy H mode operation over a wide range of elongation, triangularity and density. Divertor detachment experiments suggest the existence of recombination pathways other than three body or radiative processes.

Fully noninductive, steady-state electron cyclotron current drive (ECCD) has been demonstrated for the first time in experiments carried out in the tokamak a configuration variable (TCV) [O. Sauter , Phys. Rev. Lett. 84, 3322 (2000)]. By appropriately distributing six 0.45 MW ECCD sources over the discharge cross section, fully noninductive, stable, and stationary plasmas with I-p up to 210 kA were obtained for the full discharge duration of 1.9 s, corresponding to more than 900 energy confinement times and more than 10 current redistribution times at an average current drive efficiency eta (20CD)=0.01[10(20) A W-1 m(-2)]. These experiments have also demonstrated for the first time the steady recharging of the ohmic transformer using ECCD only. The effect of localized off-axis electron cyclotron heating (ECH) and EC current drive (ECCD) (co- and counter-) is investigated showing that locally driven currents amounting to only 1% of I-p significantly alter sawtooth periods and crash amplitudes. An improved quasi-stationary core confinement regime, with little or no sawtooth activity, has been obtained by a combination of off-axis ECH and on-axis CNTR-ECCD. (C) 2001 American Institute of Physics.

The scientific database of radiofrequency radiation (RFR) compiled from researches over 50 years indicates that the predominant effects of electromagnetic fields in the region from 100 kHz to 300 GHz are the thermal effects. Exposure of biological systems to RFR energy of sufficient intensity may lead to temperature elevation when the rate of energy absorption exceeds the rate of energy dissipation.

Details on the design, fabrication and calibration of a nominal Mach 6.5 hypersonic shock tunnel nozzle are presented. The nozzle design intent, nozzle-facility interface, material selection, and chosen method of construction are also reviewed. Flow quality based on over twenty nozzle calibration runs performed at Mach 7 and 10 flight conditions were assessed using a high-resolutio n pitot pressure survey rake. For all test runs, core flow diameters of at least 12" and 14" were achieved for the Mach 7 and 10 test conditions, respectively. Extent of this core was shown to exist up to 25" from the nozzle exit plane. Experimental data was found to correlate well with computational simulations performed with the General Aerodynamic Simulation Program (GASP v.3) in Parabolized Navier Stokes (PNS) mode taking into account finite-rate chemical kinetics.

The effect of exposure to a 50 Hz, vertical magnetic field on the excretion of urinary 6-sulphatoxymelatonin (aMT6s) of rats was studied in a self-controlled experiment. Ten male Wistar rats were kept under 9:15 h light: dark conditions in metabolic cages. The rats were exposed to 1.0 or 100 microT flux density for 24 h. The excretion of aMT6s, which is the primary metabolite of melatonin in the urine, did not show a statistically significant decrease, as measured by 125I radioimmunoassay, during or after magnetic field exposure of rats to either flux density. At 100 microT flux density, the increase of aMT6s excretion on the day after exposure was statistically significant (P.02), compared with the value under exposure, but was not significant compared with the baseline values before exposure.