1,239 research outputs found
AntArr â Etna Low Frequency Antenna Array
AbstractA project called AntArr as a new application of the DBBC3 (Digital Base Band Converter, 3rd generation) is under development. A group of antennas operating at low frequency, in the range from 10 MHz up to 1500 MHz, are phased up for VLBI, pulsar and more recently for FRB observations. Part of the scientific programme is also dedicated to SETI activities in piggy-back mode. Dedicated elements can even be added to reach still lower frequencies to observe the range down to kHz frequencies. The DBBC3 manages the array operations in a selected portion of the band and the main characteristic is to synthesize a beam with an innovative approach. The final product of the array is a single station standard VLBI data stream for correlation with other antennas, or a synthesized beam for single dish observations. A number of antennas and array prototypes are under test at a location on the Etna volcano slope, with the aim to form a complete radio telescope of up to 1024 elements in 2020 and beyond. This project completes the lower part of the frequency spectrum covered in VLBI by the BRAND EVN project. The project AntArr is hosted and financed by HAT-Lab Ltd., which is the manufacturer of the DBBC family backends
PRIVATE SAVINGS IN TRANSITION ECONOMIES: ARE THERE TERMS OF TRADE SHOCKS?
The paper examines the impact of terms of trade shocks on private savings in the transition economies after accounting for the effect of other determinants. Economic agents in the transition economies are subject to tight credit constraints which are more pronounced during bad state of nature. Thus, adverse shocks to commodity prices in the world market can force them to reduce savings by a larger amount than they would otherwise have. Empirical analysis using a dynamic panel model and data from twenty one transition economies confirm that most of the determinants of savings identified in the literature also apply to the transition economies. Favorable movements in both the permanent and transitory components of the terms of trade have a significant positive impact on private savings with transitory movements having a larger impact than the permanent component. This reflects the lack of access to foreign borrowing that many of the transition economies have faced during the last decade. Although the impact of terms of trade shocks are found to be asymmetric, the magnitude of the impact appears to be small. The results are robust for alternative estimators, determinants, and country groupings.http://deepblue.lib.umich.edu/bitstream/2027.42/39958/3/wp572.pd
Economic liberalization and the antecedents of top management teams: evidence from Turkish 'big' business
There has been an increased interest in the last two decades in top management teams (TMTs) of business firms. Much of the research, however, has been US-based and concerned primarily with TMT effects on organizational outcomes. The present study aims to expand this literature by examining the antecedents of top team composition in the context of macro-level economic change in a late-industrializing country. The post-1980 trade and market reforms in Turkey provided the empirical setting. Drawing upon the literatures on TMT and chief executive characteristics together with punctuated equilibrium models of change and institutional theory, the article develops the argument that which firm-level factors affect which attributes of TMT formations varies across the early and late stages of economic liberalization. Results of the empirical investigation of 71 of the largest industrial firms in Turkey broadly supported the hypotheses derived from this premise. In the early stages of economic liberalization the average age and average organizational tenure of TMTs were related to the export orientation of firms, whereas in later stages, firm performance became a major predictor of these team attributes. Educational background characteristics of teams appeared to be under stronger institutional pressures, altering in different ways in the face of macro-level change
Exploring the Galaxy's halo and very metal-weak thick disk with SkyMapper and Gaia DR2
In this work we combine spectroscopic information from the \textit{SkyMapper
survey for Extremely Metal-Poor stars} and astrometry from Gaia DR2 to
investigate the kinematics of a sample of 475 stars with a metallicity range of
dex. Exploiting the action map, we identify
16 and 40 stars dynamically consistent with the \textit{Gaia Sausage} and
\textit{Gaia Sequoia} accretion events, respectively. The most metal-poor of
these candidates have metallicities of and , respectively, helping to define the low-metallicity tail of the
progenitors involved in the accretion events. We also find, consistent with
other studies, that 21\% of the sample have orbits that remain confined
to within 3~kpc of the Galactic plane, i.e., |Z| 3~kpc. Of
particular interest is a sub-sample (11\% of the total) of low
|Z| stars with low eccentricities and prograde motions. The lowest
metallicity of these stars has [Fe/H] = --4.30 and the sub-sample is best
interpreted as the very low-metallicity tail of the metal-weak thick disk
population. The low |Z|, low eccentricity stars with retrograde orbits
are likely accreted, while the low |Z|, high eccentricity pro- and
retrograde stars are plausibly associated with the \textit{Gaia Sausage}
system. We find that a small fraction of our sample (4\% of the total) is
likely escaping from the Galaxy, and postulate that these stars have gained
energy from gravitational interactions that occur when infalling dwarf galaxies
are tidally disrupted.Comment: 23 pages, 15 figures, accepted for publication in MNRA
Empowering Latino parents to transform the education of their children
This article emphasizes the role of parental involvement in the college preparation of Latino elementary and secondary school students. Although literature shows that education is highly valued in Latino families, actual college enrollment rates for Latino youth are below average. This has been attributed to barriers including lack of financial resources, problems in communication with schools, and low familiarity with the college planning process. The American Dream Academy is a university outreach program that is designed to help Latino families overcome these barriers. We conducted a qualitative analysis of speeches that were prepared and delivered by parents at graduation ceremonies of the program from 2007 to 2009. Our analysis revealed six themes: facing challenges, envisioning success, understanding the school system, taking ownership, community raising a child, and creating a supportive home environment. The findings enrich existing literature and help understand the complex systems that are at play with parental involvement in Latino families
ANĂLISE DOS RUĂDOS RESPIRATĂRIOS DE CAVALOS ATLETAS NO DIAGNĂSTICO DA HEMIPLEGIA DE LARINGE
Hemiplegia of the larynx is one of the main diseases that affect the upper airway in horses. Alternative methods have been researched to determine the effects of different degrees of hemiplegia on the performance of horses. The objective of this study was to evaluate the effectiveness of employing the analysis of respiratory sounds to diagnose hemiplegia of the larynx during intense physical activity while in real conditions exercising on the track. Ten horses were used to perform this study; the horses were divided into three groups: healthy animals (control group), animals that underwent an experimental induction of hemiplegia of the larynx (HLI), andâ animals naturally affected by the disease (HL). An intranasal probe containing a microphone attached to a digital recorder was positioned in the pharynx and used to record the sounds. The sounds were transferred to a laptop and analyzed. The maximum decibel of the inhalation of HLI and HL demonstrated a significant difference when compared with control group, while the other data showed no significant differences. The magnitude of the maximum decibels of inhalation were shown to be significantly different in animals with both natural and induced forms of hemiplegia of the larynx; this method can thus be used in the diagnosis of hemiplegia of the larynx and its interference with the athletic performance of horses in field conditions.A hemiplegia de laringe Ă© uma das principais afecçÔes das vias aĂ©reas superiores nos cavalos. Pesquisas de novos mĂ©todos para determinar o efeito dos diferentes graus de hemiplegia na performance atlĂ©tica de cavalos tĂȘm sido realizadas. O objetivo do presente estudo foi avaliar a eficiĂȘncia da anĂĄlise dos ruĂdos respiratĂłrios no diagnĂłstico da hemiplegia de laringe, durante a atividade fĂsica intensa em condiçÔes reais de exercĂcio em pista. Foram utilizados dez cavalos divididos em trĂȘs grupos: animais saudĂĄveis (controle), animais induzidos experimentalmente a hemiplegia de laringe (HLI), e animais naturalmente acometidos pela doença (HL). A gravação do ĂĄudio foi realizada atravĂ©s de sonda intranasal, posicionada na faringe, contendo microfone conectado a um gravador digital, cujos dados foram posteriormente transferidos para um computador e analisados. Os decibĂ©is inspiratĂłrios mĂĄximos dos Grupos HLI e HL demonstraram diferença significativa quando comparados ao grupo controle, e os demais dados avaliados nĂŁo apresentaram diferenças significativas. A amplitude mĂĄxima dos decibĂ©is inspiratĂłrios mostrou ser significativamente diferente nos animais com hemiplegia de laringe natural e induzida, podendo desta forma ser utilizada no diagnĂłstico da interferĂȘncia da hemiplegia de laringe no desempenho atlĂ©tico de cavalos em condiçÔes de campo
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