Miracle-dz/UniFAR-FTUs huggingface dataset:
Low dust emissivities and radial variations in the envelopes of Class 0 protostars: possible signature of early grain growth

Context. Analyzing the properties of dust and its evolution in the early phases of star formation is crucial to put constraints on the collapse and accretion processes as well as on the pristine properties of planet-forming seeds. Aims. In this paper, we aim to investigate the variations of the dust grain size in the envelopes of the youngest protostars. Methods. We analyzed Plateau de Bure interferometric observations at 1.3 and 3.2 mm for 12 Class 0 protostars obtained as part of the CALYPSO survey. We performed our analysis in the visibility domain and derived dust emissivity index (β1−3mm) profiles as a function of the envelope radius at 200–2000 au scales. Results. Most of the protostellar envelopes show low dust emissivity indices decreasing toward the central regions. The decreasing trend remains after correction of the (potentially optically thick) central region emission, with surprisingly low β1−3mm < 1 values across most of the envelope radii of NGC 1333-IRAS 4A, NGC 1333-IRAS 4B, SVS13B, and Serpens-SMM4. Conclusions. We discuss the various processes that could explain such low and varying dust emissivity indices at envelope radii 200–2000 au. Our observations of extremely low dust emissivity indices could trace the presence of large (millimeter-size) grains in Class 0 envelopes, in which case our results would point to a radial increase of the dust grain size toward the inner envelope regions. While it is expected that large grains in young protostellar envelopes could be built via grain growth and coagulation, we stress that the typical timescales required to build millimeter grains in current coagulation models are at odds with the youth of our Class 0 protostars. Additional variations in the dust composition could also partly contribute to the low β1−3mm we observe. We find that the steepness of the β1−3mm radial gradient depends strongly on the envelope mass, which might favor a scenario in which large grains are built in high-density protostellar disks and transported to the intermediate envelope radii, for example with the help of outflows and winds.
Galactic Winds in Low-mass Galaxies

Stellar-feedback-driven outflows are predicted to play a fundamental role in the baryon cycle of low-mass galaxies. However, observational constraints of winds in nearby dwarf galaxies are limited, as outflows are transient, intrinsically low surface brightness features and thus difficult to detect. Using deep Hα observations, we search for winds in a sample of 12 nearby dwarfs (M* ∼ 107–109.3 M⊙) that host ongoing or recent starbursts. We detect features that we classify as winds in six galaxies, fountain candidates in five galaxies, and diffuse interstellar medium (ISM) in one system. Winds are found preferentially in galaxies with centrally concentrated star formation, while fountains are found in galaxies with spatially distributed star formation. We suggest that the concentration of star formation is a predictor for whether a low-mass galaxy will develop a wind. The spatial extent of all detected ionized gas is limited (<1/10 virial radius) and would still be considered the ISM by cosmological simulations. Our observations suggest that the majority of material expelled from dwarfs does not escape to the intergalactic medium but remains in the halo and may be recycled to the galaxies. Derived mass-loading factors range from 0.2 to 7 (with only a weak dependency on circular velocity or stellar mass), in tension with higher values in simulations needed to reproduce realistic low-mass galaxies and resolve discrepancies with ΛCDM. The sample is part of the panchromatic STARBurst IRegular Dwarf Survey—STARBIRDS—designed to characterize the starburst phenomenon in dwarf galaxies. We also report a previously uncatalogued nearby galaxy (J1118+7913).
Linear-Quadratic Mean-Field Reinforcement Learning: Convergence of Policy Gradient Methods

We investigate reinforcement learning for mean field control problems in discrete time, which can be viewed as Markov decision processes for a large number of exchangeable agents interacting in a mean field manner. Such problems arise, for instance when a large number of robots communicate through a central unit dispatching the optimal policy computed by minimizing the overall social cost. An approximate solution is obtained by learning the optimal policy of a generic agent interacting with the statistical distribution of the states of the other agents. We prove rigorously the convergence of exact and model-free policy gradient methods in a mean-field linear-quadratic setting. We also provide graphical evidence of the convergence based on implementations of our algorithms.
1 MANAGEMENT POLICIES IN THE TELECOMMUNICATION INDUSTRY IN GREECE

The purpose of this paper is to investigate the perceptions of managers concerning the impact of institutional liberalisation of telecommunication industry on market functioning and business growth. The empirical analysis is based on a survey of 44 telecommunication companies operating for the period 2001 to 2009 in the Greek economy. These are the most important firms of the specific industry. The findings indicate that liberalisation causes a substantial increase of competition between public and private companies. Price policy and marketing policy are the main competition factors. However, several barriers such as difficult access to infrastructure telecommunication networks for private entrants and not sufficient compliance of the state-owned dominant company with the rules of healthy competition hamper competition seriously. Overall, the managers of the sample firms reveal the evolution of the private sector and the new ‘business atmosphere’ in the Greek telecommunication industry as a result of liberalisation and privatization policies which are becoming very acute in Greece to face the current crisis.
EFFECT OF INJECTION OF [3-CAROTENE OR VITAMIN E AND SELENIUM ON FERTILITY OF LACTATING DAIRY COWS

Experiments tested whether supplemental antioxidants improved fertility. To test effects of 13-carotene, cows in a hot environment were injected with prostagiandin F2a (PGF2~) and were given 3 iniections, ira, of 800 rag 13-carotene or saline at Days -6 and -3 before the anticipated date of insemination and at insemination (n=37-41 inseminated cows/group). There was no effect of [3carotene on the proportion of cows detected in estrus following PGF2a , timing ofestrus after PGF2a injection or pregnancy rate in inseminated cows. In a second trial, cows in a temperate climate received intramuscular injections of vitamin E (500 nag) and selenium (50 mg) at 30 d post partum (n=97) or were untreated controls (n=89). Treatment did not affect interval from calving to first insemination or the proportion &cows pregnant at first service, but it increased the pregnancy rate at second service (69.8 vs 52.1%; P=0.07) and reduced services per conception (1.7 vs 2.0; P<0.05) and interval from calving to conception (84.6 vs 98.1; P<0.05). Thus, injection of vitamin E and selenium increased fertility in cattle that did not become pregnant at first service. © 1998 by Elsevier Science Inc.
Title TCP friendly rate adaptation for multimedia streaming in mobile ad hoc networks

Transport protocol design for supporting multimedia streaming in mobile ad hoc networks is challenging because of unique issues, including mobility-induced disconnection, reconnection, and high out-of-order delivery ratios; channel errors; and network congestion. In this work, we describe the design and implementation of a TCP-friendly transport protocol for ad hoc networks. Our key design novelty is to perform multi-metric joint identification for packet and connection behaviors based on end-to-end measurements. Our ns-2 simulations show significant performance improvement over wired TCP friendly congestion control and TCP with explicit-link-failure-notification (ELFN) support in ad hoc networks.
Distance Learning Technology Adoption: A Motivation Perspective

More than half of the colleges and universities in the U.S. are offering at least some of their classes over the Internet. While many studies have examined the effect of distance learning and online learning technologies on student learning performance, few have looked into students' attitudes toward distance learning and its impact on their selection of online learning technologies. Positive user attitude and user acceptance have been considered critical factors that contribute to the successful application and implementation of new information technologies including online learning technology. Using expectancy theory, this study seeks to explain the behavioral intention (motivation) of a student to adopt an online learning technology. Specifically, we examine the contributing factors toward students' motivation of adopting an online learning technology. The results show that students have strong preferences for the potential outcomes of online learning technologies and these preferences are consistent across individuals.
Addressing issues related to geropsychiatry and the well-being of older adults

By 2015, of the 1.1 million individuals 13 and older with HIV in the United States, approximately half will be 50 or older (Centers for Disease Control and Prevention, 2012; Kirk & Goetz, 2009). As such, finding ways to mitigate age-related problems to facilitate successful aging in this population warrants considerable attention, especially because accelerated aging may be occurring in this population (Vance, McGuinness, Musgrove, Orel, & Fazeli, 2011). Two important areas necessary for successful aging—cognition and social engagement—are of particular concern for those aging with HIV. Declines in both of these areas have been observed in this population and may have a detrimental impact on the ability to age successfully. Also, cognitive functioning affects social functioning; likewise, social functioning affects cognitive functioning (Vance, McGuinness, et al. 2011). Thus, the purpose of this article is to review the relationship between cognitive and social declines observed in older adults with HIV and examine how these two areas may have an impact on one another and one’s ability to age successfully.
Linearizing control of the anaerobic digestion with addition of acetate ( control of the anaerobic digestion )

In this paper the principle of linearizing control was applied to anaerobic digestion of organic wastes with addition of a stimulating substance (acetate). The objective consisted of regulating the biogas flow rate in the case of variations of the inlet organic pollutant. For this purpose, a new control input was introduced in the fourth order model of the process, which reflects the acetate addition. Laboratory experiments were done with step changes of this new input. New values of the model coefficients were obtained. Input–output characteristics and optimal steady states were derived analytically using different optimality criteria. The results obtained may be useful for industrial biogas plants operating with mixtures of organic wastes, where organic waste rich in acetate (e.g., vinasse) will be added as a stimulating substance. r 2005 Elsevier Ltd. All rights reserved.
Germ Cell Biology-from generation to generation 523 Germ Cell Biology – from generation to generation

Germ cells hold a unique place in the life cycle of animal species in that they are the cells that will carry the genome on to the next generation. In order to do this they must retain their DNA in a state in which it can be used to recapitulate embryonic development. In the normal life cycle, the germ cells are the only cells that retain this ability to recapitulate development, referred to as developmental totipotency. The molecular mechanisms regulating developmental potency are poorly understood. Recently its has been shown that germ cells can be turned into pluripotent stem cells when cultured in specific polypeptide growth factors that affect their survival and proliferation. The ability to manipulate developmental potency in germ cells with growth factors allows the underlying mechanisms to be dissected. Germ cells are also the only cells that undergo the unique reductive division of meiosis. This too is essential for the ability of germ cells to form the gametes that will carry the genome into the next generation. Arguably meiosis is the most important division in the life of a nascent organism. Defects in meiosis can result in embryonic or fetal loss or, if the animal survives, in the birth of an individual with chromosomal abnormalities. Recent advances in our understanding of meiosis have come from knockout mice and studies on genes identified through studies of human infertility. This review will focus on these two key aspects of germ cell biology, developmental potency and meiosis.
Serum Concentrations of 20 K Human Growth Hormone in Normal Adults and Patients with Various Endocrine Disorders

The 20K hGH isoform is produced by alternative splicing of GH mRNA, and comprises approximately 10% of all GH in the pituitary. The physiological role of 20K hGH remains to be determined partly because of the lack of a simple and specific assay. We have established sensitive enzyme-linked immunoadsorbent assays (ELISAs) specific to 20K and 22K hGH. The serum levels of 20K hGH after overnight fasting was 118 ± 178 pg/mL (N = 282) in normal women, significantly higher than in normal men (64± 170 pg/mL, N=226). However, there was no difference in the proportion of 20K hGH to 20K plus 22K hGH between men (6.3 ±2.6%, N= 176) and women (6.3±2.1 0, N=263). No correlation was detected between the ratio of 20K hGH and age, body height, body weight or body fat mass in normal subjects. The proportion of 20K hGH was significantly (P<0.001) higher in patients with active acromegaly (9.2±2.2%, N = 33) and in patients with anorexia nervosa (9.0± 1.9, N = 8), both of which are characterized by chronic elevation of circulating GH levels. The proportion of the 20K hGH in successfully treated acromegalic patients did not differ from that in normal subjects, suggesting that GH-producing pituitary tumors secrete a higher proportion of 20K hGH, or chronic excess of 22K hGH altering the metabolic clearance rate of 20K hGH. The values in patients with adult growth hormone deficiency (GHD), hyperthyroidism, primary hypothyroidism, or GH-independent short stature did not differ from those in normal subjects. The 20K ratio did not change after acute GH provocative tests such as insulin tolerance test and GRH test. These results suggest that secretion of 20K hGH from the pituitary is under the same control as that of 22K hGH.
SYSTEMATIC PALEONTOLOGY Class Amphibia Linné , 1758 Order Salientia Laurenti , 1768 Family uncertain Genus Czatkobatrachus

Czatkobatrachus polonicus Evans et Borsuk−Białynicka, 1998 is a stem−frog from the Early Triassic karst locality of Czatkowice 1 (southern Poland). It was described and named on the basis of a small collection of vertebrae, ilia, and forelimb bones, with subsequent description of the scapulocoracoid. Further skeletal elements have now been recovered. Here we present a complete overview of the available material of Czatkobatrachus, give an extended diagno− sis of the genus, and provide an assessment of its relevance to our understanding of the early stages of salientian evolution. Czatkobatrachus has an anuran type ilium, a urodelan−like scapulocoracoid, unfused epipodials, a moderately shortened presacral column, and a very short tail of separate caudal vertebrae. The strongly ossified ends of the proximal limb bones suggest terrestrial life. The skull is unknown.
Kinixys homeana Bell 1827 – Home’s Hinge-Back Tortoise

070.1 Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group A.G. J. Rhodin, P.C. H. Pritchard, P.P. van Dijk, R.A. Saumure, K.A. Buhlmann, J.B. Iverson, and R.A. Mittermeier, Eds. Chelonian Research Monographs (ISSN 1088-7105) No. 5, doi:10.3854/crm.5. 070.homeana. v1.2013 © 2013 by Chelonian Research Foundation • Published 31 December 2013
Biogeographic analysis of Jurassic – Early Cretaceous wood assemblages from Gondwana

The terrestrial biogeography of Gondwana during Jurassic–Early Cretaceous times is poorly resolved, and the flora is usually considered to have been rather uniform. This is surprising given the size of Gondwana, which extended from the equator to the South Pole. Documenting Gondwanan terrestrial floristic provincialism in the Jurassic–Early Cretaceous times is important because it provides a historical biogeographic context in which to understand the tremendous evolutionary radiations that occurred during the mid-Cretaceous. In this paper, the distribution of Jurassic–Early Cretaceous fossil wood is analysed at generic level across the entire supercontinent. Specifically, wood assemblages are analyzed in terms of five climatic zones (summer wet, desert, winter wet, warm temperate, cool temperate) established on the basis of independent data. Results demonstrate that araucarian-like conifer wood was a dominant, cosmopolitan element, whereas other taxa showed a greater degree of provincialism. Indeed, several narrowly endemic morphogenera are recognizable from the data. 0034-6667/$ see front matter D 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.revpalbo. 2004.01. 005 * Corresponding author. E-mail addresses: philippe@univ-lyon1.fr (M. Philippe), bamfordm@geosciences.wits. ac.za (M. Bamford), s.mcloughlin@qut.edu.au (S. McLoughlin), paleobotany@bol.com. br (L.S.R. Alves), howard.falcon-lang@bristol.ac. uk (H.J. Falcon-Lang), pringepa@impsat1.com. ar (S. Gnaedinger), ottone@tango.gl. fcen.uba. ar (E.G. Ottone), mpole@marine.uq. edu.au (M. Pole), annamraju_2000@yahoo.com (A. Rajanikanth), rshoemaker@towson.edu (R.E. Shoemaker), ttorres@abello.dic. uchile.cl (T. Torres), abzamu@netverk.com. ar (A. Zamuner). M. Philippe et al. / Review of Palaeobotany and Palynology 129 (2004) 141–173 142 Finally, comparisons with Laurasian wood assemblages indicate strong parallelism between the vegetation of both hemispheres. D 2004 Elsevier B.V. All rights reserved.
Wave-and tidally-driven flow and sediment flux across a fringing coral reef : Southern Molokai , Hawaii

The fringing coral reef off the south coast of Molokai, Hawaii is currently being studied as part of a US Geological Survey (USGS) multi-disciplinary project that focuses on geologic and oceanographic processes that affect coral reef systems. For this investigation, four instrument packages were deployed across the fringing coral reef during the summer of 2001 to understand the processes governing fine-grained terrestrial sediment suspension on the shallow reef flat (h 1⁄4 1m) and its advection across the reef crest and onto the deeper fore reef. The time–series measurements suggest the following conceptual model of water and fine-grained sediment transport across the reef: Relatively cool, clear water flows up onto the reef flat during flooding tides. At high tide, more deep-water wave energy is able to propagate onto the reef flat and larger Trade wind-driven waves can develop on the reef flat, thereby increasing sediment suspension. Trade wind-driven surface currents and wave breaking at the reef crest cause setup of water on the reef flat, further increasing the water depth and enhancing the development of depth-limited waves and sediment suspension. As the tide ebbs, the water and associated suspended sediment on the reef flat drains off the reef flat and is advected offshore and to the west by Trade windand tidallydriven currents. Observations on the fore reef show relatively high turbidity throughout the water column during the ebb tide. It therefore appears that high suspended sediment concentrations on the deeper fore reef, where active coral growth is at a maximum, are dynamically linked to processes on the muddy, shallow reef flat. Published by Elsevier Ltd.
Developing oral communication in Spanish lower-level courses: The case of voice recording and videoconferencing activities

Abstract This study adds to the literature on computer-mediated communication (CMC) by examining the impact of online voice recording (VR) activities and peer-to-peer videoconferencing (VC) conversations on the development of beginning Spanish learners’ speaking performance. Specifically, this paper explores (1) whether VR and VC activities promote oral proficiency, and if so, whether those gains can be seen both in presentational and interpersonal modes of communication; and (2) whether VR and VC activities foster oral proficiency in similar ways to face-to-face (F2F) communication. A quasi-experimental, pre-/post-test design was used in the study. Three sections of a first semester Spanish course were assigned to one of the following conditions: F2F, VR, and VC. Complexity, accuracy, and fluency measures were used to analyze learners’ speaking performance in the two tasks. A mixed effects model analysis was used to investigate differences across time as well as among groups. Results show that both F2F communication and VR activities promote complexity and fluency in presentational tasks and fluency in interpersonal tasks, although F2F produces superior results regarding complexity in presentational tasks. VC activities promote complexity and fluency in presentational tasks and complexity, accuracy, and fluency in interpersonal tasks. Overall, this study shows that medium is not merely a delivery device but has important implications for learning outcomes. In this sense, these findings contribute to answering the wider question of how the use of technology in second language instruction plays a decisive role in current teaching practices.
Social relations and academic success in the German educational system

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