Multi-parton interactions and rapidity gap survival probability in jet-gap-jet processes

We discuss an application of dynamical multi-parton interaction model, tuned to measurements of underlying event topology, for a description of destroying rapidity gaps in the jet-gap-jet processes at the LHC. We concentrate on the dynamical origin of the mechanism of destroying the rapidity gap. The cross section for jet-gap-jet is calculated within LL BFKL approximation. We discuss the topology of final states without and with the MPI effects. We discuss some examples of selected kinematical situations (fixed jet rapidities and transverse momenta) as distributions averaged over the dynamics of the jet-gap-jet scattering. The color-singlet ladder exchange amplitude for the partonic subprocess is implemented into the \textsc{Pythia 8} generator, which is then used for hadronisation and for the simulation of the MPI effects. Several differential distributions are shown and discussed. We present the ratio of cross section calculated with and without MPI effects as a function of rapidity gap in between the jets.Comment: 18 pages, 10 figure

Occurrence of Calendar Anomalies in Dividend Companies – the Case of Quarter-of-the-Year Effect

Theoretical background: The efficient-market hypothesis (EMH) states that share prices immediately and fully reflect all information available on the market, so stock investors are not able to “beat the market” in the long term. Since stock exchanges are not fully efficient, there are numerous exceptions to EMH, called market anomalies (seasonal anomalies, fundamental anomalies, etc.). The occurrence of such anomalies enables stock investors to achieve excess market returns. Therefore, market anomalies are of particular interest to them. However, there are no studies on “beating the market” in the long term by dividend investing. Research to date has focused mainly on the short-term response of the capital market to dividend announcements.Purpose of the article: The purpose of this paper is to examine whether by dividend investing stock investor is able to “beat the market” on quarterly basis, i.e. achieve excess market returns in some quarters of the year. In order to conduct the research, the following hypothesis was formulated: The average rates of return on the dividend index are higher in the third quarter of the calendar year than the average rates of return on other indices.Research methods: The study was carried out in the period between 2012 and 2019 on the Warsaw Stock Exchange (WSE) using rates of return on income indices (i.e. WIG, WIGdiv, WIG20TR, WIG30TR, mWIG40TR and sWIG80TR). The main method used for the calculation was Kruskal–Wallis H test.Main findings: Average returns on examined indices were negative in the second quarter of the year. Our finding is consistent with the so-called holiday effect. The highest rates of return occurred in the third quarter, except for small and medium companies. In these cases, the highest returns were observed in the first quarter). The study conducted with the use of the Kruskal–Wallis H test showed that the null hypothesis, stating that the cases come from the same population, cannot be rejected.Theoretical background: The efficient-market hypothesis (EMH) states that share prices immediately and fully reflect all information available on the market, so stock investors are not able to “beat the market” in the long term. Since stock exchanges are not fully efficient, there are numerous exceptions to EMH, called market anomalies (seasonal anomalies, fundamental anomalies, etc.). The occurrence of such anomalies enables stock investors to achieve excess market returns. Therefore, market anomalies are of particular interest to them. However, there are no studies on “beating the market” in the long term by dividend investing. Research to date has focused mainly on the short-term response of the capital market to dividend announcements.Purpose of the article: The purpose of this paper is to examine whether by dividend investing stock investor is able to “beat the market” on quarterly basis, i.e. achieve excess market returns in some quarters of the year. In order to conduct the research, the following hypothesis was formulated: The average rates of return on the dividend index are higher in the third quarter of the calendar year than the average rates of return on other indices.Research methods: The study was carried out in the period between 2012 and 2019 on the Warsaw Stock Exchange (WSE) using rates of return on income indices (i.e. WIG, WIGdiv, WIG20TR, WIG30TR, mWIG40TR and sWIG80TR). The main method used for the calculation was Kruskal–Wallis H test.Main findings: Average returns on examined indices were negative in the second quarter of the year. Our finding is consistent with the so-called holiday effect. The highest rates of return occurred in the third quarter, except for small and medium companies. In these cases, the highest returns were observed in the first quarter). The study conducted with the use of the Kruskal–Wallis H test showed that the null hypothesis, stating that the cases come from the same population, cannot be rejected

Maximal Androgen Ablation: A Review

Primary management of advanced (stage D) adenocarcinoma of the prostate is androgen ablation. Since this principle was discovered in the early 1940s, therapeutic alternatives and progress have centered around different ways to obtain castrate levels of androgens. The role of adrenal androgens in supporting prostate or prostatic cancer growth has been debated for decades and until recently was believed to be minimal. In the 1980s the concept of maximum androgen suppression, involving both the testes and adrenal glands, was reintroduced with some investigators claiming exceptional results. We review studies that have examined this concept, with emphasis on the largest trial which was carried out by the National Cancer Institute

On the assignability of regularity coefficients and central exponents of discrete linear time-varying systems

In this paper we investigate the problem of assignability of the so-called regularity coefficients and central exponents of discrete linear time-varying systems. The main result presents a possibility of assignability of Lyapunov, Perron, Grobman regularity coefficients and central exponents by a linear time-varying feedback under the assumptions of uniform complete controllability