Disk wind feedback from high-mass protostars

We perform a sequence of 3D magnetohydrodynamic (MHD) simulations of the outflow-core interaction for a massive protostar forming via collapse of an initial cloud core of $60~{M_\odot}$. This allows us to characterize the properties of disk wind driven outflows from massive protostars, which can allow testing of different massive star formation theories. It also enables us to assess quantitatively the impact of outflow feedback on protostellar core morphology and overall star formation efficiency. We find that the opening angle of the flow increases with increasing protostellar mass, in agreement with a simple semi-analytic model. Once the protostar reaches $\sim24~{M_\odot}$ the outflow's opening angle is so wide that it has blown away most of the envelope, thereby nearly ending its own accretion. We thus find an overall star formation efficiency of $\sim50\%$, similar to that expected from low-mass protostellar cores. Our simulation results therefore indicate that the MHD disk wind outflow is the dominant feedback mechanism for helping to shape the stellar initial mass function from a given prestellar core mass function.Comment: Accepted for publication in Ap

Outflow-Confined HII regions. II. The Early Break-Out Phase

In this series of papers, we model the formation and evolution of the photoionized region and its observational signatures during massive star formation. Here we focus on the early break out of the photoionized region into the outflow cavity. Using results of 3-D magnetohydrodynamic-outflow simulations and protostellar evolution calculations, we perform post-processing radiative-transfer. The photoionized region first appears at a protostellar mass of 10Msun in our fiducial model, and is confined to within 10-100AU by the dense inner outflow, similar to some observed very small hypercompact HII regions. Since the ionizing luminosity of the massive protostar increases dramatically as Kelvin-Helmholz (KH) contraction proceeds, the photoionized region breaks out to the entire outflow region in <10,000yr. Accordingly, the radio free-free emission brightens significantly in this stage. In our fiducial model, the radio luminosity at 10 GHz changes from 0.1 mJy kpc2 at m=11Msun to 100 mJy kpc2 at 16Msun, while the infrared luminosity increases by less than a factor of two. The radio spectral index also changes in the break-out phase from the optically thick value of 2 to the partially optically thin value of 0.6. Additionally, we demonstrate that short-timescale variation in free-free flux would be induced by an accretion burst. The outflow density is enhanced in the accretion burst phase, which leads to a smaller ionized region and weaker free-free emission. The radio luminosity may decrease by one order of magnitude during such bursts, while the infrared luminosity is much less affected, since internal protostellar luminosity dominates over accretion luminosity after KH contraction starts. Such variability may be observable on timescales as short 10-100 yr, if accretion bursts are driven by disk instabilities.Comment: 9 pages, 5 figures, accepted for publication in Ap

Family transitions and changes in drinking from adolescence through mid-life

AIMS: To examine how changes in social roles, particularly in the family, predict rises and falls in alcohol consumption from ages 16 to 50 years. DESIGN: Longitudinal data from the National Child Development Study. SETTING: The birth cohort includes 99% of British infants born in 1 week in 1958. Participants After initial assessment of 17,415 infants, the cohort was interviewed at ages 7, 11, 16, 23, 33, 42, 46, and 50. This study uses the six adolescent to adult waves (n = 7212 women, 7377 men). MEASUREMENTS: Alcohol use [i.e. quantity consumed in past week and heavy daily drinking), symptoms of problem drinking (i.e. Cut-down, Annoyed, Guilt, Eye-opener (CAGE)] and social roles (i.e. union formation, parenthood and employment). FINDINGS: Estimates from fixed-effects models demonstrate that alcohol use is lower when women reside with child(ren) under age 5, compared to occasions when they do not [estimate = -0.38, 95% confidence interval (CI) = -0.43, -0.32 for past week units; odds ratio (OR) = 0.47, CI = 0.36, 0.62 for heavy-daily drinking; OR = 0.66, CI = 0.50, 0.87 for CAGE symptoms]. Associations are similar for men (estimate = -0.29, CI = -0.36, -0.23; OR = 0.64, CI = 0.53, 0.77; OR = 0.69, CI = 0.51, 0.94, respectively). When women and men are married, working and residing with young child(ren), past week units (estimate = -0.51, CI = -0.61, -0.41 for women; estimate = -0.34, CI = -0.44, -0.25 for men), heavy-daily drinking (OR = 0.49, CI = 0.30, 0.79 for women; OR = 0.47, CI = 0.35, 0.64 for men) and CAGE (OR = 0.44, CI = 0.23, 0.83 for women; OR = 0.39, CI = 0.18, 0.82 for men) are lower compared to occasions when they are not in these roles. CONCLUSIONS: From late adolescence to mid-life, women and men in Britain are most at risk for higher levels of alcohol consumption and problem drinking when family roles are absent

The SOFIA Massive (SOMA) Star Formation Survey. I. Overview and First Results

We present an overview and first results of the Stratospheric Observatory For Infrared Astronomy Massive (SOMA) Star Formation Survey, which is using the FORCAST instrument to image massive protostars from $\sim10$--$40\:\rm{\mu}\rm{m}$. These wavelengths trace thermal emission from warm dust, which in Core Accretion models mainly emerges from the inner regions of protostellar outflow cavities. Dust in dense core envelopes also imprints characteristic extinction patterns at these wavelengths, causing intensity peaks to shift along the outflow axis and profiles to become more symmetric at longer wavelengths. We present observational results for the first eight protostars in the survey, i.e., multiwavelength images, including some ancillary ground-based MIR observations and archival {\it{Spitzer}} and {\it{Herschel}} data. These images generally show extended MIR/FIR emission along directions consistent with those of known outflows and with shorter wavelength peak flux positions displaced from the protostar along the blueshifted, near-facing sides, thus confirming qualitative predictions of Core Accretion models. We then compile spectral energy distributions and use these to derive protostellar properties by fitting theoretical radiative transfer models. Zhang and Tan models, based on the Turbulent Core Model of McKee and Tan, imply the sources have protostellar masses $m_*\sim10$--50$\:M_\odot$ accreting at $\sim10^{-4}$--$10^{-3}\:M_\odot\:{\rm{yr}}^{-1}$ inside cores of initial masses $M_c\sim30$--500$\:M_\odot$ embedded in clumps with mass surface densities $\Sigma_{\rm{cl}}\sim0.1$--3$\:{\rm{g\:cm}^{-2}}$. Fitting Robitaille et al. models typically leads to slightly higher protostellar masses, but with disk accretion rates $\sim100\times$ smaller. We discuss reasons for these differences and overall implications of these first survey results for massive star formation theories.Comment: Accepted to ApJ, 32 page

The SOFIA Massive (SOMA) Star Formation Survey. II. High Luminosity Protostars

We present multi-wavelength images observed with SOFIA-FORCAST from $\sim$10 to 40 $\mu$m of seven high luminosity massive protostars, as part of the SOFIA Massive (SOMA) Star Formation Survey. Source morphologies at these wavelengths appear to be influenced by outflow cavities and extinction from dense gas surrounding the protostars. Using these images, we build spectral energy distributions (SEDs) of the protostars, also including archival data from Spitzer, Herschel and other facilities. Radiative transfer (RT) models of Zhang & Tan (2018), based on Turbulent Core Accretion theory, are then fit to the SEDs to estimate key properties of the protostars. Considering the best five models fit to each source, the protostars have masses $m_{*} \sim 12-64 \: M_{\odot}$ accreting at rates of $\dot{m}_{*} \sim 10^{-4}-10^{-3} \: M_{\odot} \: \rm yr^{-1}$ inside cores of initial masses $M_{c} \sim 100-500 \: M_{\odot}$ embedded in clumps with mass surface densities $\Sigma_{\rm cl} \sim 0.1-3 \: \rm g \: cm^{-2}$ and span a luminosity range of $10^{4} -10^{6} \: L_{\odot}$. Compared with the first eight protostars in Paper I, the sources analyzed here are more luminous, and thus likely to be more massive protostars. They are often in a clustered environment or have a companion protostar relatively nearby. From the range of parameter space of the models, we do not see any evidence that $\Sigma_{\rm cl}$ needs to be high to form these massive stars. For most sources the RT models provide reasonable fits to the SEDs, though the cold clump material often influences the long wavelength fitting. However, for sources in very clustered environments, the model SEDs may not be such a good description of the data, indicating potential limitations of the models for these regions.Comment: 30 pages, 19 figures, Accepted for publication in Ap

Significance of Soil Lightness Versus Physicochemical Soil Properties in Semiarid Areas

This is an author's accepted manuscript of an article published in " Arid Land Research and Management"; Volume 28, Issue 4, 2014; copyright Taylor & Francis; available online at: http://www.tandfonline.com/doi/abs/10.1080/15324982.2014.882871Modern agriculture aims to encompass all soil attributes to optimize soil use and minimize environmental impacts. One of those attributes is soil color, which allows determining important soil variables for crop management and soil conservation. In this study, the relationships between lightness and several pedologic, topographic, and soil management variables were determined. One hundred and ten topsoil points were sampled in an area where the Mediterranean climate is the only homogeneous soil forming factor. Soil samples were air dried, crushed, and sieved, and lightness measurements were made using a trichromatic colorimeter. The relationships between lightness and soil-related parameters were carried out by means of bivariate linear correlation, and Mann-Witney and Kruskal-Wallis tests. Soil textural fractions (sand and silt), electrical conductivity and carbonates were statistically significant (p<0.001) and exhibited moderate correlation coefficients (0.32 0.45). Topographic variables (slope and aspect), soil organic carbon, iron, nitrogen, pH, and parent material (marls) exhibited lower effect on lightness. The response of lightness to clay content was highly conditioned by iron content. Stoniness, phosphorous, elevation, and soil management variables (irrigation and land use) were not statistically significant. The results obtained with calcareous samples from semiarid areas showed that soil lightness behavior agree with findings in developed soils, despite of the large differences in soil composition and the heterogeneity of the study area.Moreno-Ramón, H.; Marqués-Mateu, Á.; Ibañez Asensio, S. (2014). Significance of Soil Lightness Versus Physicochemical Soil Properties in Semiarid Areas. Arid Land Research and Management. 28(4):371-382. doi:10.1080/15324982.2014.882871S371382284Al-Mahawili , S. M. H. , M. F. Baumgardner , R. A. Weismiller , and W. N. Melhorn . 1983 . Satellite image interpretation and laboratory spectral reflectance measurements of saline and gypsiferous soils of West Baghdad, Iraq.LARS Technical Reports. Paper 104.Barrett, L. R. (2002). Spectrophotometric color measurement in situ in well drained sandy soils. Geoderma, 108(1-2), 49-77. doi:10.1016/s0016-7061(02)00121-0Bogrekci, I., & Lee, W. S. (2005). Spectral Phosphorus Mapping using Diffuse Reflectance of Soils and Grass. Biosystems Engineering, 91(3), 305-312. doi:10.1016/j.biosystemseng.2005.04.015Buol, S. W., Southard, R. J., Graham, R. C., & McDaniel, P. A. (2011). Soil Genesis and Classification. doi:10.1002/9780470960622Christensen, L. K., Bennedsen, B. S., Jørgensen, R. N., & Nielsen, H. (2004). Modelling Nitrogen and Phosphorus Content at Early Growth Stages in Spring Barley using Hyperspectral Line Scanning. Biosystems Engineering, 88(1), 19-24. doi:10.1016/j.biosystemseng.2004.02.006Doi, R., Wachrinrat, C., Teejuntuk, S., Sakurai, K., & Sahunalu, P. (2009). Semiquantitative color profiling of soils over a land degradation gradient in Sakaerat, Thailand. Environmental Monitoring and Assessment, 170(1-4), 301-309. doi:10.1007/s10661-009-1233-xDuiker, S. W., Rhoton, F. E., Torrent, J., Smeck, N. E., & Lal, R. (2003). Iron (Hydr)Oxide Crystallinity Effects on Soil Aggregation. Soil Science Society of America Journal, 67(2), 606. doi:10.2136/sssaj2003.0606Ehsani, M. R., Upadhyaya, S. K., Slaughter, D., Shafii, S., & Pelletier, M. (1999). Precision Agriculture, 1(2), 219-236. doi:10.1023/a:1009916108990Gunal, H., Ersahin, S., Yetgin, B., & Kutlu, T. (2008). Use of Chromameter‐Measured Color Parameters in Estimating Color‐Related Soil Variables. Communications in Soil Science and Plant Analysis, 39(5-6), 726-740. doi:10.1080/00103620701879422Ibarra-F., F. A., Martin-R., M. H., Cox, J. R., Crowl, T. A., Post, D. F., Miller, R. W., & Rasmussen, G. A. (1995). Relationship between Buffelgrass Survival, Organic Carbon, and Soil Color in Mexico. Soil Science Society of America Journal, 59(4), 1120. doi:10.2136/sssaj1995.03615995005900040025xKonen, M. E., Burras, C. L., & Sandor, J. A. (2003). Organic Carbon, Texture, and Quantitative Color Measurement Relationships for Cultivated Soils in North Central Iowa. Soil Science Society of America Journal, 67(6), 1823. doi:10.2136/sssaj2003.1823Mouazen, A. M., Maleki, M. R., De Baerdemaeker, J., & Ramon, H. (2007). On-line measurement of some selected soil properties using a VIS–NIR sensor. Soil and Tillage Research, 93(1), 13-27. doi:10.1016/j.still.2006.03.009Pan, G., Xu, X., Smith, P., Pan, W., & Lal, R. (2010). An increase in topsoil SOC stock of China’s croplands between 1985 and 2006 revealed by soil monitoring. Agriculture, Ecosystems & Environment, 136(1-2), 133-138. doi:10.1016/j.agee.2009.12.011Sánchez-Marañón, M., Martín-García, J. M., & Delgado, R. (2011). Effects of the fabric on the relationship between aggregate stability and color in a Regosol–Umbrisol soilscape. Geoderma, 162(1-2), 86-95. doi:10.1016/j.geoderma.2011.01.008Sánchez-Marañón, M., Ortega, R., Miralles, I., & Soriano, M. (2007). Estimating the mass wetness of Spanish arid soils from lightness measurements. Geoderma, 141(3-4), 397-406. doi:10.1016/j.geoderma.2007.07.005Sánchez-Marañón, M., Delgado, G., Melgosa, M., Hita, E., & Delgado, R. (1997). CIELAB COLOR PARAMETERS AND THEIR RELATIONSHIP TO SOIL CHARACTERISTICS IN MEDITERRANEAN RED SOILS. Soil Science, 162(11), 833-842. doi:10.1097/00010694-199711000-00007Singleton, P. (1991). Water tables and soil colour as an indicator of saturation in some soils of the Waikato, New Zealand. Soil Research, 29(4), 467. doi:10.1071/sr9910467Spielvogel, S., Knicker, H., & Kögel-Knabner, I. (2004). Soil organic matter composition and soil lightness. Journal of Plant Nutrition and Soil Science, 167(5), 545-555. doi:10.1002/jpln.200421424Viscarra Rossel, R. A., Minasny, B., Roudier, P., & McBratney, A. B. (2006). Colour space models for soil science. Geoderma, 133(3-4), 320-337. doi:10.1016/j.geoderma.2005.07.017Webster, R., & Oliver, M. A. (2007). Geostatistics for Environmental Scientists. Statistics in Practice. doi:10.1002/978047051727

At an important tephrostratigraphic crossroads: cryptotephra in Late Glacial to Early Holocene lake sediments from the Carpathian Mountains, Romania

Understanding the temporal and spatial environmental response to past climate change during the Last Glacial-Interglacial Transition (LGIT, 16-8 ka) across Europe relies on precise chronologies for palaeoenvironmental records. Tephra layers (volcanic ash) are a powerful chronological tool to synchronise disparate records across the continent. Yet, some regions remain overlooked in terms of cryptotephra investigations. Building on earlier work at the same sites, we present the first complete LGIT high-resolution cryptotephra investigation of two lake records in the Carpathian Mountains in Romania, Lake Brazi and Lake Lia. Numerous volcanic glass shards have been recognised as originating from various volcanic regions, including: Iceland (Katla, Askja, and Torfajokull), Italy (Campi Flegrei, Ischia, Lipari, and Pantelleria), and central Anatolia (Acigol and Ericyes). In total, four distinct tephra horizons have now been identified in these records: 1) an LGIT Lipari tephra (11,515–12,885 cal BP, 95.4% range); 2) Askja-S (11,070–10,720 cal BP, 95.4% range); 3) an Early Holocene Lipari tephra,(12,590–10,845 cal BP, 95.4% range) and; 4) an Early Holocene Ischia tephra (11,120–10,740 cal BP, 95.4% range). The use of trace element analysis on selected cryptotephra layers provided additional important information in identifying volcanic source and facilitating correlations. These tephra layers, along with numerous other discrete cryptotephra layers, offer promise as significant future isochrons for comprehending the spatial and temporal fluctuations in past climate change throughout Europe and the Mediterranean area. This research has emphasized the significance of the Carpathian region in expanding the European and Mediterranean tephra lattice and establishing it as a keystone area within the framework

Incremental dimension reduction of tensors with random index

We present an incremental, scalable and efficient dimension reduction technique for tensors that is based on sparse random linear coding. Data is stored in a compactified representation with fixed size, which makes memory requirements low and predictable. Component encoding and decoding are performed on-line without computationally expensive re-analysis of the data set. The range of tensor indices can be extended dynamically without modifying the component representation. This idea originates from a mathematical model of semantic memory and a method known as random indexing in natural language processing. We generalize the random-indexing algorithm to tensors and present signal-to-noise-ratio simulations for representations of vectors and matrices. We present also a mathematical analysis of the approximate orthogonality of high-dimensional ternary vectors, which is a property that underpins this and other similar random-coding approaches to dimension reduction. To further demonstrate the properties of random indexing we present results of a synonym identification task. The method presented here has some similarities with random projection and Tucker decomposition, but it performs well at high dimensionality only (n>10^3). Random indexing is useful for a range of complex practical problems, e.g., in natural language processing, data mining, pattern recognition, event detection, graph searching and search engines. Prototype software is provided. It supports encoding and decoding of tensors of order >= 1 in a unified framework, i.e., vectors, matrices and higher order tensors.Comment: 36 pages, 9 figure

Components of Behavioral Parent Training for Children With Attention-Deficit/Hyperactivity Disorder:A Series of Replicated Single-Case Experiments

Behavioral parent training (BPT) is an evidence-based treatment for children with attention-deficit/hyperactivity disorder (ADHD). Stimulus control techniques (antecedent-based techniques, e.g., clear rules, instructions) and contingency management techniques (consequent-based techniques, e.g., praise, ignore) are the most common ones that are being taught to parents in BPT. However, research into the additive effects of these techniques is scarce. In this replicated single-case experimental ABC phase design, including six children on stable medication for ADHD (8–11 years) and their parents, the added efficacy of consequent-based techniques on top of antecedent-based techniques was evaluated. After a baseline period (phase A), we randomized the commencement time of two sessions parent training in antecedent-based techniques and two sessions parent training in consequent-based techniques for each child. Children’s behaviors were assessed by daily parent ratings of selected problem behaviors and an overall behavior rating. Although visual inspection showed that behavior improved for most children in both phases, randomization tests did not demonstrate the added efficacy of the consequent-based techniques on top of the antecedent-based techniques. Limitations of the study and recommendations for future single-case experiments in this population are discussed.</p