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Number of results: 68
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Abstract

Prof. Mirosław Wielgoś, MD, Rector at the Medical University of Warsaw, talks about why women of all ages should undergo prenatal testing and where they can turn for help.
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Abstract

We talk about the importance of psychoeducation for heart patients with Anna Mierzyńska and Karolina Jurczak of the Cardinal Stefan Wyszyński Institute of Cardiology in Anin.
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Abstract

Titanium dioxide (TiO2) is a popular pigment known as titania white. However, it has many other properties that support various applications.
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Abstract

We talk to Dr. Maciej Jórdeczka from the PAS Institute of Archaeology and Ethnology in Poznań about archaeological surprises, Neolithic medicine and paying respect to our deceased.
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We talk about technology, lexicography, and long-forgotten word senses in Polish with Prof. Włodzimierz Gruszczyński from the PAS Institute of the Polish Language, where work is underway on the Electronic Dictionary of the Polish Language of the 17th and 18th Centuries.
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Abstract

We have evidence of a meteorite impact near the village of Morasko in Poland around 5,500 years ago. What can it tell us about the past and the future?
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Dr. Agata Karska of the Nicolaus Copernicus University in Toruń talks about the valuable time we get from ESO, visiting Chile without leaving home, and the opportunities for young scientists in Poland.
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Abstract

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics. Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points. Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.
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Abstract

Knowledge of having a deadly disease usually causes severe psychological problems, depression, or even PTSD. Can this be avoided? Can one find something positive in a tragic situation?
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Abstract

When and where did life first appear on Earth? Humankind has been pondering this question for centuries. The discovery of ancient microalgae is providing a partial answer.
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Abstract

“Soon we will be able to fit the contents of the Encyclopedia Britannica on a head of a pin,” the famous physicist Richard Feynman argued back in the 1960s. Perhaps even he would be amazed at the possibilities now offered by carbon nanotubes, several hundred thousand times tinier than a pin. Their amazing properties have been exploited in an integrated circuit developed at the Karlsruhe Institut für Technologie.
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Abstract

Over half of all organisms living on Earth today are parasites, and there are hardly any species which are free from them. How can the “wild immunology” approach help us understand them better?
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Abstract

What is patriotism as opposed to nationalism? And which of these is what sometimes surfaces in contemporary rock music?
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Abstract

Prof. Małgorzata Kossut of the Nencki Institute of Experimental Biology talks about brain plasticity, the mechanisms of learning, and the mysteries of forgetfulness.
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Abstract

Polish Sign Language (PJM) is a natural communication system that has been evolving for two centuries. It is at the heart of the identity and culture of the Deaf community in Poland, but it is often marginalized and neglected. It first came under serious linguistic scrutiny not long ago, and more systematic research on it has been initiated in recent years by a team of researchers at the Section for Sign Linguistics at the University of Warsaw.
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Abstract

Animals kept outside their natural environment often suffer from boredom. They don’t hunt or have a chance to conduct their mating rituals, and their natural tendency for physical activity is limited by space. These deficiencies affect their psychological well-being. But when it comes to dogs, we can help them by exploiting their excellent sense of smell.
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Abstract

To learn about fish of the Oligocene period, one must first travel to the Carpathian Mountains and slowly smash rocks.
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Abstract

Once a ban on speaking in foreign languages in public is introduced, one’s head can cease to be a fighting tool, and will be used solely in accordance with its original purpose.
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Abstract

These days, a kind of information embargo is increasingly being applied, to ensure that only selected scientific information is accessible only to selected recipients at the right time.
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Abstract

The first so-called hybrid MSV-MGARCH models were characterized by the conditional covariance matrix that was a product of a univariate latent process and a matrix with a simple MGARCH structure (Engle’s DCC or scalar BEKK). The aim was to parsimoniously describe volatility of a large group of assets. The proposed hybrid models, similarly as pure MSV specifications (and other models based on latent processes), required the Bayesian approach equipped with efficient MCMC simulation tools. The numerical effort has payed – the hybrid models seem particularly useful due to their good fit and ability to jointly cope with large portfolios. In particular, the simplest hybrid, now called the MSF-SBEKK model, has been successfully used in many applications. However, one latent process may be insufficient in the case of a highly heterogeneous portfolio. Thus, in this study we discuss a general hybrid MSV-MGARCH model structure, showing its basic characteristics that explain greater flexibility of such hybrid structure with respect to the corresponding MGARCH class. From the empirical perspective, we advocate the GMSF-SBEKK specification, which uses as many latent processes as there are relatively homogeneous groups of assets. We present full Bayesian inference for such models, with the use of an efficient MCMC simulation strategy. The approach is used to jointly model volatility on very different markets. Joint modelling is formally compared to individual modelling of volatility on each market.
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Abstract

We apply Bayesian inference to estimate transformation matrix that converts vector of industry outputs from NACE Rev. 1.1 to NACE Rev. 2 classification. In formal terms, the studied issue is a representative of the class of matrix balancing (updating, disaggregation) problems, often arising in the field of multi-sector economic modelling. These problems are characterised by availability of only partial, limited data and a strong role for prior assumptions, and are typically solved using bi-proportional balancing or cross-entropy minimisation methods. Building on Bayesian highest posterior density formulation for a similarly structured case, we extend the model with specification of prior information based on Dirichlet distribution, as well as employ MCMC sampling. The model features a specific likelihood, representing accounting restrictions in the form of an underdetermined system of equations. The primary contribution, compared to the alternative, widespread approaches, is in providing a clear account of uncertainty.
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Abstract

Small sample properties of unrestricted and restricted canonical correlation estimators of cointegrating vectors for panel vector autoregressive process are considered when the cross-sectional dependencies occur in the process generating nonstationary panel data. It is shown that the unrestricted Box-Tiao estimator is slightly outperformed by the unrestricted Johansen estimator if the dynamic properties of the underlying process are correctly specified. The comparison of performance of the restricted canonical correlation estimator of cointegrating vectors for the panel VAR and for the classical VAR applied independently for each cross-section reveals that the latter performs better in small samples when the cross-sectional dependence is limited to the error terms correlations, even though it is inefficient in the limit, but it falls short in comparison to the former when there are cross-sectional dependencies in the short-run dynamics and/or in the long-run adjustments.
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