scholarly journals Redshifted 21-cm bispectrum – I. Impact of the redshift space distortions on the signal from the Epoch of Reionization

2020 ◽  
Vol 499 (4) ◽  
pp. 5090-5106
Author(s):  
Suman Majumdar ◽  
Mohd Kamran ◽  
Jonathan R Pritchard ◽  
Rajesh Mondal ◽  
Arindam Mazumdar ◽  
...  

ABSTRACT The bispectrum can quantify the non-Gussianity present in the redshifted 21-cm signal produced by the neutral hydrogen ($\rm {H \small {I}}$) during the Epoch of Reionization (EoR). Motivated by this, we perform a comprehensive study of the EoR 21-cm bispectrum using simulated signals. Given a model of reionization, we demonstrate the behaviour of the bispectrum for all unique triangles in k space. For ease of identification of the unique triangles we parametrize the k-triangle space with two parameters, namely the ratio of the two arms of the triangle (n = k2/k1) and the cosine of the angle between them (cos θ). Furthermore, for the first time we quantify the impact of the redshift space distortions (RSD) on the spherically averaged EoR 21-cm bispectrum in the entire unique triangle space. We find that the real space signal bispectra for small and intermediate k1-triangles ($k_1 \le 0.6 \, \, {\rm Mpc}^{-1}$) is negative in most of the unique triangle space. It takes a positive sign for squeezed, stretched, and linear k1-triangles, specifically for large k1 values ($k_1 \ge 0.6 \, \, {\rm Mpc}^{-1}$). The RSD affects both the sign and magnitude of the bispectra significantly. It changes (increases/decreases) the magnitude of the bispectra by $50\!-\!100{{\ \rm per\ cent}}$ without changing its sign (mostly) during the entire period of the EoR for small and intermediate k1-triangles. For larger k1-triangles, RSD affects the magnitude by $100\!-\!200{{\ \rm per\ cent}}$ and also flips the sign from negative to positive. We conclude that it is important to take into account the impact of RSD for a correct interpretation of the EoR 21-cm bispectra.

Author(s):  
Maria Giulia Ballatore ◽  
Ettore Felisatti ◽  
Laura Montanaro ◽  
Anita Tabacco

This paper is aimed to describe and critically analyze the so-called "TEACHPOT" experience (POT: Provide Opportunities in Teaching) performed during the last few years at Politecnico di Torino. Due to career criteria, the effort and the time lecturers spend in teaching have currently undergone a significant reduction in quantity. In order to support and meet each lecturers' expectations towards an improvement in their ability to teach, a mix of training opportunities has been provided. This consists of an extremely wide variety of experiences, tools, relationships, from which everyone can feel inspired to increase the effectiveness of their teaching and the participation of their students. The provided activities are designed around three main components: methodological training, teaching technologies, methodological experiences. A discussion on the findings is included and presented basing on the data collected through a survey. The impact of the overall experience can be evaluated on two different levels: the real effect on redesigning lessons, and the discussion on the matter within the entire academic community.


CFA Digest ◽  
2006 ◽  
Vol 36 (3) ◽  
pp. 36-37
Author(s):  
Brendan F. O'Connell
Keyword(s):  
The Real ◽  

2019 ◽  
Vol 12 (3) ◽  
pp. 86-92
Author(s):  
T. I. Minina ◽  
V. V. Skalkin

Russia’s entry into the top five economies of the world depends, among other things, on the development of the financial sector, being a necessary condition for the economic growth of a developed macroeconomic and macro-financial system. The financial sector represents a system of relationships for the effective collection and distribution of economic resources, their deployment according to public demand, reducing the risk of overproduction and overheating of the economy.Therefore, the subject of the research is the financial sector of the Russian economy.The purpose of the research was to formulate an approach to alleviating the risks of increasing financial costs in the real sector of the economy by reducing the impact of endogenous risks expressed as financial asset “bubbles” using the experience of developed countries in the monetary policy.The paper analyzes a macroeconomic model applied to the financial sector. It is established that the economic growth is determined by the growth and, more important, the qualitative development of the financial sector, which leads to two phenomena: overproduction in the real sector and an increase in asset prices in the financial sector, with a debt load in both the real and financial sectors. This results in decreasing the interest rate of the mega-regulator to near-zero values. In this case, since the mechanisms of the conventional monetary policy do not work, the unconventional monetary policy is used when the mega-regulator buys out derivative financial instruments from systemically important institutions. As a conclusion, given deflationally low rates, it is proposed that the megaregulator should issue its own derivative financial instruments and place them in the financial market.


2020 ◽  
pp. 42-60
Author(s):  
S. N. Liutova ◽  
I. I. Dronova

The article reveals the names of the prototypes of certain characters in Nagibin’s long story My Golden Mother-in-Law [Moya zolotaya tyoshcha] (the mother-in-law being A. Likhachyova, the wife of the director of the Moscow Car Manufacturing Plant ZIL). For the first time we read the names and learn about the destiny of M. and L. Kostromin, the real people behind the characters of Matvey Matveevich, the neighbour, and Nina Petrovna, the female protagonist’s best friend. The life story of these personalities, residents of the legendary Niernsee House in Bolshoy Gnezdnikovsky Lane, enables the authors, who are related to L. Kostromina, to explain the underpinnings of the relationships between the prototypes of Nagibin’s characters, often a mystery for the writer himself, and share first-hand accounts that confirm his amazing flair for imagination. The article uses materials of family lore, the authors’ private archive (letters and photographs), as well as hitherto unsearched materials from state archives.


2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Bibi Tahira ◽  
Naveed Saif ◽  
Muhammad Haroon ◽  
Sadaqat Ali

The current study tries to understand the diverse nature of relationship between personality Big Five Model (PBFM) and student's perception of abusive supervision in higher education institutions of Khyber Pakhtoonkhwa Pakistan. Data was collected in dyads i.e. (supervisors were asked to rate their personality attributes while student were asked to rate the supervisor behavior) through adopted construct. For this purpose, data was collected from three government state universities and one Private Sector University. The focus was on MS/M.Phill and PhD student and their supervisors of the mentioned universities. After measuring normality and validity regression analysis was conducted to assess the impact of supervisor personality characteristics that leads to abusive supervision. Findings indicate interestingly that except agreeableness other four attributes of (PBFM) are play their role for abusive supervision. The results are novel in the nature as for the first time Neuroticism, openness to experience, extraversion and conscientiousness are held responsible for the abusive supervision. The study did not explore the demographic characteristics, and moderating role of organizational culture, justice and interpersonal deviances to understand the strength of relationship in more detail way. Keywords: Personality big five model, abusive supervision, HEIs


Author(s):  
Dr. Jianfei Yang

COVID-19 has made a bad influence on economic and society including cultural and tourism industry in China,2020.The industry has received a huge loss in the first quarter of the year and the situation is getting worse in the near future. It is believed that there will be a long impact for the country even the world. In order to recover the industry, Chinese government has published series of policies to support the enterprises and clusters to reduce the bad influence of COVID-19. This paper mainly uses filed survey and documentary research to map the real situation of the industry. It tries to find the policy demand of the industries and then analyze the policies published by government to conquer COVID-19. Meanwhile it will focus on whether the supply meet the demand and give suggestions on how to promote the policy efficiency in the post period of COVID-19 in China. Keywords: Evaluation; Cultural Industries; Policy; Park; Pandemic


2019 ◽  
Vol 5 (1) ◽  
pp. 18-25
Author(s):  
Isah Funtua Abubakar ◽  
Umar Bambale Ibrahim

This paper attempts to study the Nigerian agriculture industry as a panacea to growth as well as an anchor to the diversification agenda of the present government. To do this, the time series data of the four agriculture subsectors of crop production, livestock, forestry and fishery were analysed as stimulus to the Real GDP from 1981-2016 in order to explicate the individual contributions of the subsectors to the RGDP in order to guide the policy thrust on diversification. Using the Johansen approach to cointegration, all the variables were found to be cointegrated. With the exception of the forestry subsector, all the three subsectors were seen to have impacted on the real GDP at varying degrees during the time under review. The crop production subsector has the highest impact, however, taking size-by-size analysis, the livestock subsector could be of much importance due to its ability to retain its value chain and high investment returns particularly in poultry. Therefore, it is recommended that, the government should intensify efforts to retain the value chain in the crop production subsector, in order to harness its potentials optimally through the encouragement of the establishment of agriculture cottage industries. Secondly, the livestock subsector is found to be the most rapidly growing and commercialized subsector. Therefore, it should be the prime subsector to hinge the diversification agenda naturally. Lastly, the tourism industry which is a source through which the impact of the subsector is channeled to the GDP should be developed, in order to improve the impact of such channel to GDP with the sole objective to resuscitate the forestry subsector.


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