scholarly journals Intermittency and Anisotropy in the Ionized Interstellar Medium

2017 ◽  
Vol 13 (S337) ◽  
pp. 283-286
Author(s):  
Barney Rickett
Keyword(s):  
Simple Model ◽  
Interstellar Medium ◽  
Plasma Turbulence ◽  
Anisotropic Scattering ◽  
Hot Stars ◽  
Interstellar Plasma ◽  
The Rich ◽  
The Many ◽  
Phase Screens ◽  
Uniform Plasma

AbstractThe discovery of pulsars was closely followed by the discovery of dispersion and scattering in the interstellar plasma (ionized interstellar medium - IISM). The rich phenomena of scattering and scintillation have since been successfully modelled as propagation through a statistically uniform plasma turbulence with an isotropic Kolmogorov spectrum of density. However, this enticingly simple model fails to explain the many recent observations, that show anisotropic scattering from highly localized regions of the IISM often referred to as phase screens. I summarize the recent evidence from pulsars and also from very compact AGN sources, which can exhibit rapid scintillation and occasionally ESEs. The unknown astrophysical origin of these phenomena includes thin current sheets, the diffuse remnants of old supernova shells, and plasma filaments surrounding ubiquitous molecular clumps near young hot stars.

scholarly journals Constraints on Interstellar Plasma Turbulence Spectrum from Pulsar Observations at the Ooty Radio Telescope

2000 ◽  
Vol 177 ◽  
pp. 553-554
Author(s):  
N. D. Ramesh Bhat ◽  
Yashwant Gupta ◽  
A. Pramesh Rao
Keyword(s):  
Interstellar Medium ◽  
Radio Telescope ◽  
Underlying Mechanism ◽  
Plasma Turbulence ◽  
Density Fluctuations ◽  
Interstellar Scintillation ◽  
Interstellar Plasma ◽  
Scale Range ◽  
Turbulence Data

Refractive Interstellar Scintillation (RISS) effects on pulsar signals are powerful techniques for discriminating between different models that have been proposed for the power spectrum of plasma density fluctuations in the Interstellar Medium (ISM; e.g. Rickett 1990). The nature of the spectrum is considered to be a major input for understanding the underlying mechanism of interstellar plasma turbulence. Data from our long-term pulsar scintillation observations using the Ooty Radio Telescope (ORT) at 327 MHz are used to investigate the nature of the spectrum in the Local Interstellar Medium (LISM; region within ∼ 1 kpc of the Sun). Dynamic scintillation spectra were obtained for 18 pulsars in the DM range 3–35 pc cm−3at ∼10–100 epochs spanning ∼100–1000 days during 1993–1995 (Bhat et al. 1999). From these observations, various scintillation properties and the ISM parameters are estimated with accuracies much better than that which has been possible from most earlier data. The time series of parameters,viz., decorrelation bandwidth (vd), scintillation time scale (τd) and the drift slope of intensity scintillation patterns, and pulsar flux density are used to study various observable effects of Interstellar Scintillation, based on which the spectral form is inferred over the spatial scale range ∼ 107m to ∼ 1013m.

Language and the Many Histories of Brazilian Inequality

2011 ◽  
Vol 9 ◽  
Author(s):  
Brodwyn Fischer
Keyword(s):  
Educational Policies ◽  
Social Difference ◽  
Gender Dynamics ◽  
Language Literacy ◽  
The Rich ◽  
Language And Education ◽  
And Gender ◽  
The Many

There are numerous historical critiques of elitist educational policies in Brazil, as well as studies of the racial and gender dynamics of education, and scholars have routinely lamented the historical lack of access to schooling among the Brazilian poor. But surprisingly few historians have taken on language and education as durable categories of inequality—created, recognized, legitimized, and acted upon over many generations, constitutive elements in Brazil’s constellation of social difference. This is especially remarkable given the rich and repeated emphasis on language, literacy, and education that characterized debates about Brazilian inequality in the century after independence.

KORŌṈĀ TOṞṞU KĀLATTIL TIṈAKKŪLIYĀḶARKAḶIṈ NILAI: KOḺUMPU - 12 PUTUKKAṬAI PIRATĒCATTAI MAIYAPPAṬUTTIYA CAMŪKAVIYAL ĀYVU [DAILY WAGE WORKERS IN COVID-19 PANDEMIC PERIOD: A SOCIOLOGICAL RESEARCH BASED ON HULFTSDORF, COLOMBO-12]

2021 ◽  
pp. 82-95
Author(s):  
M.A.F.ASHFA ◽  
M.J.F. SANA ANJUM ◽  
A. IJAS MOHAMED ◽  
M.M.F. AQEELA ◽  
M.S. ZUNOOMY
Keyword(s):  
World Economy ◽  
Emergency Situation ◽  
Primary Data ◽  
Sociological Research ◽  
Economic Problems ◽  
Depth Interview ◽  
The Rich ◽  
Mixed Approach ◽  
Daily Wage ◽  
The Many

The COVID-19 pandemic has gravely wounded the world economy with serious consequences impacting all communities and individuals. However, the rich and middle class can fill in their day to day needs, because of having enough money. At the same time, daily wage workers are facing difficulties to fill in their daily life needs in the current situation. According to this, the research aims to identify the economy level of daily wage workers of Hulftdorf, Colombo-12 during this period. The primary data were collected from 54 daily wage workers though questionnaire and in-depth interview. The gathered data were discussed by mixed approach descriptive methodology. The findings of this research declare that urban daily wage workers face the many difficulties than rural daily wage workers, because of expensive and costly price of the essential commodities. At the other hand, due to lack of daily income, they do not save the money. Thus, they face economic problems in predicaments. They also get insufficient donation, aids and relief in this emergency situation.

scholarly journals THE RICH AND THE POOR IN A SIMPLE MODEL OF GROWTH AND DISTRIBUTION

2016 ◽  
Vol 20 (7) ◽  
pp. 1934-1952 ◽  
Author(s):  
Kirill Borissov
Keyword(s):  
Economic Growth ◽  
Steady State ◽  
Simple Model ◽  
Disposable Income ◽  
State Equilibrium ◽  
Positional Concerns ◽  
The Poor ◽  
The Rich ◽  
Intertemporal Equilibrium ◽  
Unique Steady State

We consider a model of economic growth with altruistic agents who care about their consumption and the disposable income of their offspring. The agents' consumption and the offspring's disposable income are subject to positional concerns. We show that, if the measure of consumption-related positional concerns is sufficiently low and/or the measure of offspring-related positional concerns is sufficiently high, then there is a unique steady-state equilibrium, which is characterized by perfect income and wealth equality, and all intertemporal equilibira converge to it. Otherwise, in steady-state equilibria, the population splits into two classes, the rich and the poor; under this scenario, in any intertemporal equilibrium, all capital is eventually owned by the households that were the wealthiest from the outset and all other households become poor.

scholarly journals Clusters of Galaxies

1980 ◽  
Vol 5 ◽  
pp. 699-714 ◽  
Author(s):  
Neta A. Bahcall
Keyword(s):  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
Clusters Of Galaxies ◽  
Groups Of Galaxies ◽  
Formation And Evolution ◽  
The Rich ◽  
The Many ◽  
The Universe

AbstractClusters and groups of galaxies contain the majority of galaxies in the universe. The rich clusters, while less numerous than the many poor groups, are the densest and largest systems known, and can be easily recognized and studied even at relatively large distances. Their study is important for understanding the formation and evolution of clusters and galaxies, and for a determination of the large-scale structure in the universe.

scholarly journals Interplanetary and interstellar plasma turbulence

2007 ◽  
Vol 49 (5A) ◽  
pp. A195-A209 ◽  
Author(s):  
A A Schekochihin ◽  
S C Cowley ◽  
W Dorland
Keyword(s):  
Plasma Turbulence ◽  
Interstellar Plasma

A Life Recovered: Mary Hamilton 1756-1816

2014 ◽  
Vol 90 (2) ◽  
pp. 27-46 ◽  
Author(s):  
Lisa Crawley
Keyword(s):  
Eighteenth Century ◽  
Women's History ◽  
Research Tool ◽  
Intellectual Elite ◽  
The Rich ◽  
The Many ◽  
Significant Figures ◽  
Insight Into ◽  
Shed Light ◽  
Women’S History

Through her own words, Mary Hamilton demonstrates the rich resources available for the study of an elite womans life during the latter part of the eighteenth-century and allows us to resurrect more fully the life of a member of an elite circle of women during this period. Her diaries reveal the many opportunities that she had to meet with a number of the significant figures of her day, and shed light on how her academic efforts were perceived by those around her. This article shows how her writings offer researchers an insight into eighteenth-century society as viewed and lived by a woman who was close not only to the centre of high society but also to the intellectual elite of the day. It considers how valuable a resource the diaries and papers are as a potential research tool not only for the study of women‘s history but as a rich resource for the period.

Mini-conference on plasma turbulence in the corona, heliosphere and interstellar medium

2002 ◽  
Vol 9 (5) ◽  
pp. 2440-2445 ◽  
Author(s):  
W. H. Matthaeus ◽  
P. Dmitruk ◽  
L. J. Milano
Keyword(s):  
Interstellar Medium ◽  
Plasma Turbulence

scholarly journals Lag, lock, sync, slip: the many ‘phases’ of coupled flagella

2014 ◽  
Vol 11 (94) ◽  
pp. 20131160 ◽  
Author(s):  
Kirsty Y. Wan ◽  
Kyriacos C. Leptos ◽  
Raymond E. Goldstein
Keyword(s):  
High Speed ◽  
Model Organism ◽  
Dynamic Coordination ◽  
Phase Slippage ◽  
Transient Loss ◽  
Flagellar Regeneration ◽  
Resolution Imaging ◽  
The Rich ◽  
Cilia And Flagella ◽  
The Many

In a multitude of life's processes, cilia and flagella are found indispensable. Recently, the biflagellated chlorophyte alga Chlamydomonas has become a model organism for the study of ciliary motility and synchronization. Here, we use high-speed, high-resolution imaging of single pipette-held cells to quantify the rich dynamics exhibited by their flagella. Underlying this variability in behaviour are biological dissimilarities between the two flagella—termed cis and trans , with respect to a unique eyespot. With emphasis on the wild-type, we derive limit cycles and phase parametrizations for self-sustained flagellar oscillations from digitally tracked flagellar waveforms. Characterizing interflagellar phase synchrony via a simple model of coupled oscillators with noise, we find that during the canonical swimming breaststroke the cis flagellum is consistently phase-lagged relative to, while remaining robustly phase-locked with, the trans flagellum. Transient loss of synchrony, or phase slippage , may be triggered stochastically, in which the trans flagellum transitions to a second mode of beating with attenuated beat envelope and increased frequency. Further, exploiting this alga's ability for flagellar regeneration, we mechanically induced removal of one or the other flagellum of the same cell to reveal a striking disparity between the beatings of the cis and trans flagella, in isolation. These results are evaluated in the context of the dynamic coordination of Chlamydomonas flagella.

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