Bilingualism caught in a net: A new approach to understanding the complexity of bilingual experience

The growing importance of research on bilingualism in psychology and neuroscience motivates the need for a psychometric model that can be used to understand and quantify this phenomenon. This research is the first to meet this need. We reanalyzed two data sets (N = 171 and N = 112) from relatively young adult language-unbalanced bilinguals and asked whether bilingualism is best described by the factor structure or by the network structure. The factor and network models were established on one data set and then validated on the other data set in a fully confirmatory manner. The network model provided the best fit to the data. This implies that bilingualism should be conceptualized as an emergent phenomenon arising from direct and idiosyncratic dependencies among the history of language acquisition, diverse language skills, and language-use practices. These dependencies can be reduced to neither a single universal quotient nor to some more general factors. Additional in-depth network analyses showed that the subjective perception of proficiency along with language entropy and language mixing were the most central indices of bilingualism, thus indicating that these measures can be especially sensitive to variation in the overall bilingual experience. Overall, this work highlights the great potential of psychometric network modeling to gain a more accurate description and understanding of complex (psycho)linguistic and cognitive phenomena

Thermal properties of Ti-doped Cu-Zn soft ferrites used as thermally actuated material for magnetizing superconductors

A great majority of widely used ferrite ceramics exhibit a relatively high temperature of order–disorder phase transition in their magnetic subsystem. For applications related to the magnetization process of superconductors, however, a low value of T c is required. Here we report and analyze in detail the thermal properties of bulk Ti-doped Cu–Zn ferrite ceramics Cu0.3Zn0.7Ti0.04Fe1.96O4 and Mg0.15Cu0.15Zn0.7Ti0.04Fe1.96O4. They are characterized by a Curie temperature in the range 120–170 K and a maximum DC magnetic susceptibility exceeding 20 for the Cu0.3Zn0.7Ti0.04Fe1.96O4 material. The temperature dependence of both the specific heat C p and of the thermal conductivity κ, determined between 2 and 300 K, are found not to exhibit any peculiar feature at the magnetic transition temperature. The low-temperature dependence of both κ and the mean free path of phonons suggests a mesoscopic fractal structure of the grains. From the measured data, the characteristics of thermally actuated waves are estimated. The low magnetic phase transition temperature and suitable thermal parameters make the investigated ferrite ceramics applicable as magnetic wave producers in devices designed for magnetization of high-temperature superconductors.We thank the University of Liège (ULg) and the Ministry of Higher Education of Communauté Française de Belgique for a research grant Action de Recherches Concertées (ARC 11/16-03). We thank Alexander Krivchikov for fruitful discussions and Oksana Mendiuk for taking SEM images. This work is part of a collaboration programme between the FRS-FNRS (Belgium) and the PAS (Polish Academy of Sciences).This is the author accepted manuscript. The final version is available from the Institute of Physics via http://dx.doi.org/10.1088/0022-3727/49/12/12500

8 Roczne doświadczenia własne w stosowaniu brachyterapii pulsacyjnej (PDR)

Cel pracyPrzedstawiono roczne doświadczenia własne w stosowaniu brachyterapii (BT) pulsacyjnej (PDR) u chorych na nowotwory złośliwe.Materiał i metodyW okresie od 03.1999 do 06.2000 brachyterapię pulsacyjną zastosowano u 112 chorych z następującymi lokalizacjami zmian nowotworowych: drzewo oskrzelowe (21 chorych), przełyk (34 chorych), pierś (20 chorych), narząd rodny (16 chorych), przewód pokarmowy (6 chorych), rejon głowy i szyi (8 chorych), mózg (5 chorych) oraz cewka moczowa (2 chorych). W 36 przypadkach brachyterapia PDR stanowiła element leczenia radykalnego, u 76 chorych była stosowana jako leczenie paliatywne. U 5 chorych PDR stosowano w obszarze uprzednio napromienianym śródjamowo i/lub wiązką zewnętrzną. Stosowano aparat PDR firmy Nucletron, zawierający żródło Ir192 o aktywności nominalnej 1 Ci. Podczas leczenia stosowano dawki od 6 Gy do 70 Gy, podawane w pulsach powtarzanych co 1 godzinę, jednorazowo lub podczas kolejnych, cotygodniowych aplikacji. Moc dawki wynosia 0.5–1 Gy/ puls/godzinę w przypadkach leczonych radykalnie i napromienianych powtórnie, oraz 1–4 Gy/puls/godzinę lub 6 Gy w jednej aplikacji, u chorych leczonych paliatywnie. Stosowano indywidualne plany leczenia opracowane za pomocą komputerowego systemu planowania leczenia (PLATO). W przypadkach chorych na raka oskrzela i przełyku, leczonych paliatywnie, wykorzystywano własne standardy rozkładu dawki.WynikiTolerancja leczenia BT PDR była bardzo dobra, również u chorych leczonych przez okres kilku dni. U 1 chorego na raka przefyku nie zastosowano kolejnej aplikacji z uwagi na wystąpienie objawów sugerujących popromienne zapalenie przełyku. U większości chorych z objawami choroby nowotworowej leczonych paliatywnie uzyskano poprawę subiektywną.Nie stwierdzono nawrotu nowotworu u chorych napromienianych radykalnie, jakkolwiek względnie krótki okres obserwacji większości chorych nie pozwala na wyciągnięcie ostatecznych wniosków.WnioskiBT PDR pozwala na zastosowanie leczenia śródjamowego i sródtkankowego niemal we wszystkich lokalizacjach zmian nowotwotowych Poprzez zastosowanie różnych metod optymalizacji dawki oraz względnie szerokiego zakresu mocy dawki w pulsie, metoda ta pozwala na optymalny dobór sposobu leczenia u poszczegó1nych chorych

Microlensing optical depth toward the Galactic Bulge using bright sources from OGLE-II

We present a measurement of the microlensing optical depth toward the Galactic Bulge based on 4 years of the OGLE-II survey using Red Clump Giant (RCG). Using 32 events we find tau=2.55_{-0.46}^{+0.57}* 10^{-6} at (l,b)=(1.16, -2.75). Taking into account the measured gradient along the Galactic latitude b, tau = [ (4.48+/- 2.37) + (0.78+/- 0.84)* b]* 10^{-6}, this value is consistent with previous measurements using RCG sources and recent theoretical predictions. We determine the microlensing parameters and select events using a model light curve with the flux blending. We find that ~38% of the OGLE-II events which appear to have RCG sources are actually due to much fainter stars blended with a bright companion. We show explicitly that model fits without blending result in similar tau estimates through partial cancellation of contributions from higher detection efficiency, underestimated time-scales and larger number of selected events. This approach, however, leads to biased time-scale distributions and event rates. Consequently, microlensing studies should carefully consider source confusion effects even for bright stars.Comment: 49 pages and 18 figures, ApJ in press, the value changed due to the systematic correctio

Submillimeter to centimeter excess emission from the Magellanic Clouds. II. On the nature of the excess

Dust emission at submm to cm wavelengths is often simply the Rayleigh-Jeans tail of dust particles at thermal equilibrium and is used as a cold mass tracer in various environments including nearby galaxies. However, well-sampled spectral energy distributions of the nearby, star-forming Magellanic Clouds have a pronounced (sub-)millimeter excess (Israel et al., 2010). This study attempts to confirm the existence of such a millimeter excess above expected dust, free-free and synchrotron emission and to explore different possibilities for its origin. We model NIR to radio spectral energy distributions of the Magellanic Clouds with dust, free-free and synchrotron emission. A millimeter excess emission is confirmed above these components and its spectral shape and intensity are analysed in light of different scenarios: very cold dust, Cosmic Microwave Background (CMB) fluctuations, a change of the dust spectral index and spinning dust emission. We show that very cold dust or CMB fluctuations are very unlikely explanations for the observed excess in these two galaxies. The excess in the LMC can be satisfactorily explained either by a change of the spectral index due to intrinsic properties of amorphous grains, or by spinning dust emission. In the SMC however, due to the importance of the excess, the dust grain model including TLS/DCD effects cannot reproduce the observed emission in a simple way. A possible solution was achieved with spinning dust emission, but many assumptions on the physical state of the interstellar medium had to be made. Further studies, using higher resolution data from Planck and Herschel, are needed to probe the origin of this observed submm-cm excess more definitely. Our study shows that the different possible origins will be best distinguished where the excess is the highest, as is the case in the SMC.Comment: 7 pages, 6 figures; accepted in A&

Preliminary results for RR Lyrae stars and Classical Cepheids from the Vista Magellanic Cloud (VMC) Survey

The Vista Magellanic Cloud (VMC, PI M.R. Cioni) survey is collecting $K_S$-band time series photometry of the system formed by the two Magellanic Clouds (MC) and the "bridge" that connects them. These data are used to build $K_S$-band light curves of the MC RR Lyrae stars and Classical Cepheids and determine absolute distances and the 3D geometry of the whole system using the $K$-band period luminosity ($PLK_S$), the period - luminosity - color ($PLC$) and the Wesenhiet relations applicable to these types of variables. As an example of the survey potential we present results from the VMC observations of two fields centered respectively on the South Ecliptic Pole and the 30 Doradus star forming region of the Large Magellanic Cloud. The VMC $K_S$-band light curves of the RR Lyrae stars in these two regions have very good photometric quality with typical errors for the individual data points in the range of $\sim$ 0.02 to 0.05 mag. The Cepheids have excellent light curves (typical errors of $\sim$ 0.01 mag). The average $K_S$ magnitudes derived for both types of variables were used to derive $PLK_S$ relations that are in general good agreement within the errors with the literature data, and show a smaller scatter than previous studies.Comment: 7 pages, 6 figure. Accepted for publication in Astrophysics and Space Science. Following a presentation at the conference "The Fundamental Cosmic Distance Scale: State of the Art and the Gaia Perspective", Naples, May 201

A Low-Mass Planet with a Possible Sub-Stellar-Mass Host in Microlensing Event MOA-2007-BLG-192

We report the detection of an extrasolar planet of mass ratio q ~ 2 x 10^(-4) in microlensing event MOA-2007-BLG-192. The best fit microlensing model shows both the microlensing parallax and finite source effects, and these can be combined to obtain the lens masses of M = 0.060 (+0.028 -0.021) M_sun for the primary and m = 3.3 (+4.9 -1.6) M_earth for the planet. However, the observational coverage of the planetary deviation is sparse and incomplete, and the radius of the source was estimated without the benefit of a source star color measurement. As a result, the 2-sigma limits on the mass ratio and finite source measurements are weak. Nevertheless, the microlensing parallax signal clearly favors a sub-stellar mass planetary host, and the measurement of finite source effects in the light curve supports this conclusion. Adaptive optics images taken with the Very Large Telescope (VLT) NACO instrument are consistent with a lens star that is either a brown dwarf or a star at the bottom of the main sequence. Follow-up VLT and/or Hubble Space Telescope (HST) observations will either confirm that the primary is a brown dwarf or detect the low-mass lens star and enable a precise determination of its mass. In either case, the lens star, MOA-2007-BLG-192L, is the lowest mass primary known to have a companion with a planetary mass ratio, and the planet, MOA-2007-BLG-192Lb, is probably the lowest mass exoplanet found to date, aside from the lowest mass pulsar planet.Comment: Accepted for publication in the Astrophysical Journal. Scheduled for the Sept. 1, 2008 issu

A Jovian-mass Planet in Microlensing Event OGLE-2005-BLG-071

We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (<1%) photometry at the peak of the event yields an extremely high signal-to-noise ratio detection of a deviation from the light curve expected from an isolated lens. The planetary character of this deviation is easily and unambiguously discernible from the gross features of the light curve. Detailed modeling yields a tightly-constrained planet-star mass ratio of q=m_p/M=0.0071+/-0.0003. This is the second robust detection of a planet with microlensing, demonstrating that the technique itself is viable and that planets are not rare in the systems probed by microlensing, which typically lie several kpc toward the Galactic center.Comment: 4 pages. Minor changes. Accepted for publication in ApJ Letter

Functional Regeneration of Supraspinal Connections in a Patient With Transected Spinal Cord Following Transplantation of Bulbar Olfactory Ensheathing Cells With Peripheral Nerve Bridging

Treatment of patients sustaining a complete spinal cord injury remains an unsolved clinical problem because of the lack of spontaneous regeneration of injured central axons. A 38-year-old man sustained traumatic transection of the thoracic spinal cord at upper vertebral level Th9. At 21 months after injury, the patient presented symptoms of a clinically complete spinal cord injury (American Spinal Injury Association class A-ASIA A). One of the patient's olfactory bulbs was removed and used to derive a culture containing olfactory ensheathing cells and olfactory nerve fibroblasts. Following resection of the glial scar, the cultured cells were transplanted into the spinal cord stumps above and below the injury and the 8-mm gap bridged by four strips of autologous sural nerve. The patient underwent an intense pre- and postoperative neurorehabilitation program. No adverse effects were seen at 19 months postoperatively, and unexpectedly, the removal of the olfactory bulb did not lead to persistent unilateral anosmia. The patient improved from ASIA A to ASIA C. There was improved trunk stability, partial recovery of the voluntary movements of the lower extremities, and an increase of the muscle mass in the left thigh, as well as partial recovery of superficial and deep sensation. There was also some indication of improved visceral sensation and improved vascular autoregulation in the left lower limb. The pattern of recovery suggests functional regeneration of both efferent and afferent long-distance fibers. Imaging confirmed that the grafts had bridged the left side of the spinal cord, where the majority of the nerve grafts were implanted, and neurophysiological examinations confirmed the restitution of the integrity of the corticospinal tracts and the voluntary character of recorded muscle contractions. To our knowledge, this is the first clinical indication of the beneficial effects of transplanted autologous bulbar cells