The Spitzer Survey of the Small Magellanic Cloud: FIR Emission and Cold Gas in the SMC

We present new far infrared maps of the Small Magellanic Cloud (SMC) at 24, 70, and 160 microns obtained as part of the Spitzer Survey of the Small Magellanic Cloud (S3MC,Bolatto et al. 2006). These maps cover most of the active star formation in the SMC Bar and the more quiescent Wing. We combine our maps with literature data to derive the dust surface density across the SMC. We find a total dust mass of Mdust = 3 10^5 Msun, implying a dust-to-hydrogen ratio over the region studied of log D/H = -2.86, or 1-to-700, which includes H_2. Assuming the dust to trace the total gas column, we derive H_2 surface densities across the SMC. We find a total H_2 mass M_H2 = 3.2 10^7 Msun in a distribution similar to that of the CO, but more extended. We compare profiles of CO and H_2 around six molecular peaks and find that on average H_2 is more extended than CO by a factor of \sim 1.3. The implied CO-to-H_2 conversion factor over the whole SMC is XCO = 13 +/- 1 10^21 cm^-2 (K km/s)^-1. Over the volume occupied by CO we find a lower conversion factor, XCO = 6 +/- 1 10^21 cm^-2 (K km/s)^-1, which is still a few times larger than that found using virial mass methods. The molecular peaks have H_2 surface densities \Sigma_H2 \approx 180 +/- 30 Msun pc^-2, similar to those in Milky Way GMCs, and correspondingly low extinctions, A_V \sim 1 - 2 mag. To reconcile these measurements with predictions by the theory of photoionization-regulated star formation, which requires A_V \sim 6, the GMCs must be \sim 3 times smaller than our 46 pc resolution element. We find that for a given hydrostatic gas pressure, the SMC has a 2 - 3 times lower ratio of molecular to atomic gas than spiral galaxies. Combined with the lower mean densities in the SMC this may explain why this galaxy has only 10% of its gas in the molecular phase.Comment: 24 pages, 16 figures, accepted by ApJ. A version with nice figures is available at http://celestial.berkeley.edu/spitzer/publications

Multiplexed two-photon microscopy of dynamic biological samples with shaped broadband pulses.

International audienceCoherent control can be used to selectively enhance or cancel concurrent multiphoton processes, and has been suggested as a means to achieve nonlinear microscopy of multiple signals. Here we report multiplexed two-photon imaging in vivo with fast pixel rates and micrometer resolution. We control broadband laser pulses with a shaping scheme combining diffraction on an optically-addressed spatial light modulator and a scanning mirror allowing to switch between programmable shapes at kiloHertz rates. Using coherent control of the two-photon excited fluorescence, it was possible to perform selective microscopy of GFP and endogenous fluorescence in developing Drosophila embryos. This study establishes that broadband pulse shaping is a viable means for achieving multiplexed nonlinear imaging of biological tissues

Rigor periodístico de las informaciones del facebook Los no vacunados en sus seguidores. Lima. 2021

La investigación sobre el rigor periodístico de las informaciones del Facebook Los no vacunados en sus seguidores. Lima. 2021, tuvo como objetivo general: Determinar el rigor periodístico de las informaciones del Facebook Los no vacunados en sus seguidores. Lima. 2021 El nivel de la investigación es básica porque parte de un marco teórico y permanece en él debido a que esta investigación tiene como finalidad formular nuevas ideas o modificar las existentes respecto al tema del rigor periodístico. Los resultados que se obtuvo es que para los seguidores del grupo de Facebook Los no vacunados, sí existe un rigor periodístico, pero se comprobó también por la encuesta que la mayoría de los del grupo no cuestionan las informaciones que se dan a conocer sino que creen ciegamente todo lo que se publica y eso es muy peligroso porque no desarrollan un sentido crítico y los puede llevar a realizar locuras como no vacunarse, exponiendo su salud y la de sus familiares, a pesar de que hay suficiente evidencia científica que avala las vacunas y no vacunarse puede ser fatal y por lo tanto se llega a la conclusión de que esto debe cambiar porque de lo contrario las personas caerán en la desinformación

Influence of Apical Patency on the Adaptation of the Master Filling Cone: A Cone-beam Computed Tomography Assessment

Introduction: This study aimed to evaluate if the apical patency can influence the adaptation of the master cone of gutta-percha, quantifying the volume of voids and areas at the last 2 mm of the working length (WL). Materials and Methods: Sixty distobuccal canals of extracted upper molars were divided into 3 groups (n=20) based on the patency length (A: passed 1 mm beyond the apical foramen (AF), B: at the AF and C: 1 mm short of the AF) with the Easy ProDesign Logic 25/0.01 file. Each group was subdivided into 2 subgroups (n=10) based on the WL established to prepare the root canal (1: 1 mm short of the AF or 2: at the AF) with the Easy ProDesign Logic 25/0.05 file. After the scan, void volumes were calculated from the last 2 mm of the WL and void areas at 0 mm, 1 mm and 2 mm of the last of WL, as well as the relation between the tip and taper of the master cone with the amount of void volume and areas. To investigate statistically significant differences, we used the Kruskal-Wallis statistical test. Results: There were more voids in volume when patency was achieved 1 mm beyond the AF and the root canal preparation was conducted at 1mm short of the AF (A1 group). Furthermore, the same group showed more voids areas, mainly on the last millimeter of WL. Conclusion: Achieving apical patency at 1 mm beyond the AF followed by instrumentation 1 mm short of the AF created more voids between the master gutta-percha cone and the root canal wall, especially on the last millimeter of WL

Delayed sleep phase cases and controls

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

The Relationship Between Molecular Gas, HI, and Star Formation in the Low-Mass, Low-Metallicity Magellanic Clouds

The Magellanic Clouds provide the only laboratory to study the effect of metallicity and galaxy mass on molecular gas and star formation at high (~20 pc) resolution. We use the dust emission from HERITAGE Herschel data to map the molecular gas in the Magellanic Clouds, avoiding the known biases of CO emission as a tracer of H$_{2}$. Using our dust-based molecular gas estimates, we find molecular gas depletion times of ~0.4 Gyr in the LMC and ~0.6 SMC at 1 kpc scales. These depletion times fall within the range found for normal disk galaxies, but are shorter than the average value, which could be due to recent bursts in star formation. We find no evidence for a strong intrinsic dependence of the molecular gas depletion time on metallicity. We study the relationship between gas and star formation rate across a range in size scales from 20 pc to ~1 kpc, including how the scatter in molecular gas depletion time changes with size scale, and discuss the physical mechanisms driving the relationships. We compare the metallicity-dependent star formation models of Ostriker, McKee, and Leroy (2010) and Krumholz (2013) to our observations and find that they both predict the trend in the data, suggesting that the inclusion of a diffuse neutral medium is important at lower metallicity.Comment: 24 pages, 14 figures, accepted for publication in ApJ. FITS files of the dust-based estimates of the H2 column densities for the LMC and SMC (shown in Figures 2 and 3) will be available online through Ap

Potential applications of automated video-image analysis in the pelagic and demersal environtment including the deep-sea

Martech 2009 Third Marine Technology Workshop, 19-20 november 2009, Vilanova i la Geltrú, Barcelona.-- 2 pages, 3 figuresThis work was funded by the project High Vision (DM 19177/7303/08) from the Italian Ministry of Agricultural, Food and Forestry PoliticsPeer reviewe

Human Trypanosoma cruzi chronic infection leads to individual level steady-state parasitemia: Implications for drug-trial optimization in Chagas disease

Parasitemia; Parasitic diseases; Bloodstream infectionsParasitemia; Enfermedades parasitarias; Infecciones del torrente sanguíneoParasitèmia; Malalties parasitàries; Infeccions del torrent sanguiniCurrently available drugs against Trypanosoma cruzi infection, which causes 12000 deaths annually, have limitations in their efficacy, safety and tolerability. The evaluation of therapeutic responses to available and new compounds is based on parasite detection in the bloodstream but remains challenging because a substantial proportion of infected individuals have undetectable parasitemia even when using diagnostic tools with the highest accuracy. We characterize parasite dynamics which might impact drug efficacy assessments in chronic Chagas by analyzing pre- and post-treatment quantitative-PCR data obtained from blood samples collected regularly over a year. We show that parasitemia remains at a steady-state independently of the diagnostic sensitivity. This steady-state can be probabilistically quantified and robustly predicted at an individual level. Furthermore, individuals can be assigned to categories with distinct parasitological status, allowing a more detailed evaluation of the efficacy outcomes and adjustment for potential biases. Our analysis improves understanding of parasite dynamics and provides a novel background for optimizing future drug efficacy trials in Chagas disease