The explosive molecular outflow detected decades ago in the Orion BN/KL region of massive star formation was considered to be a bizarre event. This belief was strengthened by the nondetection of ...similar cases over the years with the only exception of the marginal case of DR21. Here, we confirm a similar explosive outflow associated with the UCHII region G5.89−0.39 that indicates that this phenomenon is not unique to Orion or DR21. Sensitive and high angular resolution (∼0 1) Atacama Large Millimeter/submillimeter Array (ALMA) CO(2−1) and SiO(5−4) observations show that the molecular outflow in the massive star-forming region G5.89−0.39 is indeed an explosive outflow with an age of about 1000 yr and a liberated kinetic energy of 1046-49 erg. Our new CO(2−1) ALMA observations revealed over 30 molecular filaments, with Hubble-like expansion motions, pointing to the center of UCHII region. In addition, the SiO(5−4) observations reveal warmer and strong shocks very close to the origin of the explosion, confirming the true nature of the flow. A simple estimation for the occurrence of these explosive events during the formation of the massive stars indicates an event rate of once every ∼100 yr, which is close to the supernovae rate.
Young massive stars in the center of crowded star clusters are expected to undergo close dynamical encounters that could lead to energetic, explosive events. However, there has so far never been ...clear observational evidence of such a remarkable phenomenon. We here report new interferometric observations that indicate the well-known enigmatic wide-angle outflow located in the Orion BN/KL star-forming region to have been produced by such a violent explosion during the disruption of a massive young stellar system, and that this was caused by a close dynamical interaction about 500 years ago. This outflow thus belongs to a totally different family of molecular flows that is not related to the classical bipolar flows that are generated by stars during their formation process. Our molecular data allow us to create a three-dimensional view of the debris flow and to link this directly to the well-known Orion H{sub 2} 'fingers' farther out.
Objective
This study aimed to describe the development of a food frequency questionnaire (FFQ) to assess dietary intake in South American children and adolescents.
Methods
A total of 345 children ...(aged 3‐10 years) and 357 adolescents (aged 11‐17 years) were included for analysis. The FFQ was designed to be self‐administered and to assess dietary intake over the past 3 months. It was developed in Spanish and translated into Portuguese. Multiple approaches were considered to compile the food list, and 11 food groups were included. A food photo booklet was produced as supporting material.
Results
The FFQ items maintained a common core list among centers (47 items) and country‐specific foods. The FFQ for Buenos Aires and Lima had a total of 63 items; there were 55 items for the FFQ in Medelin, 60 items for Montevideo, 58 items for Santiago, 67 items for Sao Paulo, and 68 items for Teresina. Alcohol was also incorporated in the adolescents' FFQ.
Conclusions
We developed a semiquantitative, culturally adapted FFQ to assess dietary intake in children and adolescents in South America. It has an optimal size allowing its completion in a high proportion of the population; therefore, it can be used in epidemiological studies with South American children and adolescents.
We present the super(12)CO(2-1) line and 1.4 mm continuum archival observations, made with the Submillimeter Array, of the outflow HH 797 located in the IC 348 cluster in Perseus. The continuum ...emission is associated with a circumstellar disk surrounding the class 0 object IC 348-MMS/SMM2, a very young solar analog. The line emission, on the other hand, delineates a collimated outflow and reveals velocity asymmetries about the flow axis over the entire length of the flow. The amplitude of velocity differences is of the order of 2 km s super(-1) over distances of about 1000 AU, and we interpret them as evidence for jet rotation-although we also discuss alternative possibilities. A comparison with theoretical models suggests that the magnetic field lines threading the protostellar jet might be anchored to the disk of a radius of about 20 AU.
We present sensitive, high angular resolution (~0".2) submillimeter continuum and line observations of IRAS 16293-2422B made with the Atacama Large Millimeter/Submillimeter Array. The 0.45 mm ...continuum observations reveal a single and very compact source associated with IRAS 16293-2422B. This submillimeter source has a deconvolved angular size of about 400 mas (50 AU) and does not show any inner structure inside of this diameter. The H super(13)CN, HC super(15)N, and CH sub(3)OH line emission regions are about twice as large as the continuum emission and reveal a pronounced inner depression or "hole" with a size comparable to that estimated for the submillimeter continuum. We suggest that the presence of this inner depression and the fact that we do not see an inner structure (or a flat structure) in the continuum are produced by very optically thick dust located in the innermost parts of IRAS 16293-2422B. All three lines also show pronounced inverse P-Cygni profiles with infall and dispersion velocities larger than those recently reported from observations at lower frequencies, suggesting that we are detecting faster and more turbulent gas located closer to the central object. Finally, we report a small east-west velocity gradient in IRAS 16293-2422B that suggests that its disk plane is likely located very close to the plane of the sky.
Few genetic polymorphisms predict early response to anti-TNF drugs in inflammatory bowel disease (IBD), and even fewer have been identified in the pediatric population. However, it would be of ...considerable clinical interest to identify and validate genetic biomarkers of long-term response. Therefore, the aim of the study was to analyze the usefulness of biomarkers of response to anti-TNFs in pediatric IBD (pIBD) as long-term biomarkers and to find differences by type of IBD and type of anti-TNF drug. The study population comprised 340 children diagnosed with IBD who were treated with infliximab or adalimumab. Genotyping of 9 selected SNPs for their association with early response and/or immunogenicity to anti-TNFs was performed using real-time PCR. Variants C rs10508884 (CXCL12), A rs2241880 (ATG16L1), and T rs6100556 (PHACTR3) (p value 0.049; p value 0.03; p value 0.031) were associated with worse long-term response to anti-TNFs in pIBD. DNA variants specific to disease type and anti-TNF type were identified in the pediatric population. Genotyping of these genetic variants before initiation of anti-TNFs would enable, if validated in a prospective cohort, the identification of pediatric patients who are long-term responders to this therapy.
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We present sensitive 2.1 and 3.3 cmJansky Very Large Array radio continuum observations of the region IC 348SW. We detect a total of 10 compact radio sources in the region, 7 of which are first ...reported here. One of the sources is associated with the remarkable periodic time-variable infrared source LRLL 54361, opening the possibility of monitoring this object at radio wavelengths. Four of the sources appear to be powering outflows in the region, including HH 211 and HH 797. In the case of the rotating outflow HH 797, we detect a double radio source at its center, separated by ~3". Two of the sources are associated with infrared stars that possibly have gyrosynchrotron emission produced in active magnetospheres. Finally, three of the sources are interpreted as background objects.
AB Aur is a Herbig Ae star with a transitional disk. Transitional disks present substantial dust clearing in their inner regions, most probably because of the formation of one or more planets, ...although other explanations are still viable. In transitional objects, accretion is found to be about an order of magnitude smaller than in classical full disks. Since accretion is believed to be correlated with outflow activity, centimeter free-free jets are expected to be present in association with these systems, at weaker levels than in classical protoplanetary (full) systems. We present new observations of the centimeter radio emission associated with the inner regions of AB Aur and conclude that the morphology, orientation, spectral index, and lack of temporal variability of the centimeter source imply the presence of a collimated, ionized outflow. The radio luminosity of this radio jet is, however, about 20 times smaller than that expected for a classical system of similar bolometric luminosity. We conclude that centimeter continuum emission is present in association with stars with transitional disks, but at levels than are becoming detectable only with the upgraded radio arrays. On the other hand, assuming that the jet velocity is 300 km s super(-1), we find that the ratio of mass loss rate to accretion rate in AB Aur is ~0.1, similar to that found for less evolved systems.
We present archival high angular resolution (~2") super(12)CO(3-2) line and continuum submillimeter observations of the young stellar object HL Tau made with the Submillimeter Array. The ...super(12)CO(3-2) line observations reveal the presence of a compact and wide opening angle bipolar outflow with a northeast to southwest orientation (P.A. = 50degrees) that is associated with the optical and infrared jet emanating from HL Tau with a similar orientation. On the other hand, the 850 mu m continuum emission observations exhibit a strong and compact source in the position of HL Tau that has a spatial size of ~200 x 70 AU with a P.A. = 145degrees and a dust mass of around 0.1M sub(middot in circle). These physical parameters are in agreement with values obtained recently from millimeter observations. This submillimeter source is therefore related to the disk surrounding HL Tau.
We present sensitive high angular resolution (∼0 1-0 3) continuum Atacama Large Millimeter/Submillimeter Array (ALMA) observations of the archetypal hot core located in the Orion Kleinmann-Low (KL) ...region. The observations were made in five different spectral bands (bands 3, 6, 7, 8, and 9) covering a very broad range of frequencies (149-658 GHz). Apart from the well-known millimeter emitting objects located in this region (Orion Source I and BN), we report the first submillimeter detection of three compact continuum sources (ALMA1-3) in the vicinities of the Orion-KL hot molecular core. These three continuum objects have spectral indices between 1.47 and 1.56, and brightness temperatures between 100 and 200 K at 658 GHz, suggesting that we are seeing moderate, optically thick dust emission with possible grain growth. However, as these objects are not associated with warm molecular gas, and some of them are farther out from the molecular core, we thus conclude that they cannot heat the molecular core. This result favors the hypothesis that the hot molecular core in Orion-KL core is heated externally.
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