Golden-Mean and Secret Sharing Matroids

<p>Maximum-sized results are an important part of matroid theory, and results currently exist for various classes of matroids. Archer conjectured that the maximum-sized golden-mean matroids fall into three distinct classes, as op- posed to the one class of all current results. We will prove a partial result that we hope will lead to a full proof. In the second part of this thesis, we look at secret sharing matroids, with a particular emphasis on the class of group-induced p-representable matroids, as introduced by Matúš. We give new proofs for results of Matúš', relating to M(K₄), F₇ and F⁻₇. We show that the techniques used do not extend in some natural ways, and pose some unanswered questions relating to the structure of secret sharing matroids.</p>

Golden-Mean and Secret Sharing Matroids

<p>Maximum-sized results are an important part of matroid theory, and results currently exist for various classes of matroids. Archer conjectured that the maximum-sized golden-mean matroids fall into three distinct classes, as op- posed to the one class of all current results. We will prove a partial result that we hope will lead to a full proof. In the second part of this thesis, we look at secret sharing matroids, with a particular emphasis on the class of group-induced p-representable matroids, as introduced by Matúš. We give new proofs for results of Matúš', relating to M(K₄), F₇ and F⁻₇. We show that the techniques used do not extend in some natural ways, and pose some unanswered questions relating to the structure of secret sharing matroids.</p>

Strong complete minors in digraphs

Kostochka and Thomason independently showed that any graph with average degree $\Omega(r\sqrt{\log r})$ contains a $K_r$ minor. In particular, any graph with chromatic number $\Omega(r\sqrt{\log r})$ contains a $K_r$ minor, a partial result towards Hadwiger’s famous conjecture. In this paper, we investigate analogues of these results in the directed setting. There are several ways to define a minor in a digraph. One natural way is as follows. A strong $\overrightarrow{K}_{\!\!r}$ minor is a digraph whose vertex set is partitioned into r parts such that each part induces a strongly connected subdigraph, and there is at least one edge in each direction between any two distinct parts. We investigate bounds on the dichromatic number and minimum out-degree of a digraph that force the existence of strong $\overrightarrow{K}_{\!\!r}$ minors as subdigraphs. In particular, we show that any tournament with dichromatic number at least 2r contains a strong $\overrightarrow{K}_{\!\!r}$ minor, and any tournament with minimum out-degree $\Omega(r\sqrt{\log r})$ also contains a strong $\overrightarrow{K}_{\!\!r}$ minor. The latter result is tight up to the implied constant and may be viewed as a strong-minor analogue to the classical result of Kostochka and Thomason. Lastly, we show that there is no function $f\;:\;\mathbb{N} \rightarrow \mathbb{N}$ such that any digraph with minimum out-degree at least f(r) contains a strong $\overrightarrow{K}_{\!\!r}$ minor, but such a function exists when considering dichromatic number.

Pengaruh Tampilan dan Konten Terhadap Efektivitas Promosi Melalui Website pada Pt.Elegant Tour And Travel Medan

The research is a quantitative research that aims to determine the effect of the displayand content on the effectiveness of promotions through the website on PT. Elegant Tour and Travel Medan.This research is conducted by observing PT. Elegant Tour and Travel Medan's website directly. Data collection methods are conducted by spreading online questioners to 96 respondents. The sample selection technique using random sampling. Data from 96 respondents were then analyzed through multiple linear regression analysis with the help of SPSS 20.The result showed adjusted r square value of 0,440 means that 44% of the effectiveness of promotion through the website is influenced by display and content while about 56% is influenced by another factors out of research. The result of testing regression coefficient simultaneously obtained f count of 38,324 > f table which is 3,09 with significance value 0,000 < 0,05. Partial result of hypothesis testing obtained t count of display > t table content (2,275>1,98552) and t count content > t table (8,077>1,98552). From this test it can be conclude that display and content have a positive and significant effect on the effectiveness of promotion through the website on PT. Elegant Tour and Travel Medan.

Perception of car brands with an emphasis on expected benefits and features as prerequisites for customer satisfaction

Brand management plays a crucial role in increasing the loyalty of current customers as well as in gaining new customers. The product brand significantly influences shopping behaviour of customers. Many customers prefer branded products to non-branded ones. Some of them prefer branded products in general; some of them prefer branded products only for selected products. This paper is focused on the analysis of the perception of ten favourite car brands by Slovak consumers with an emphasis on the quality, prestige, image and expected benefits and features. The aims of the paper are divided into three main parts: i) find out the selected car brand rank based on the influence on the purchasing behaviour of Slovak consumers; ii) assess the impact of selected socio-demographic characteristics on the expected benefits as well as on the features that the respondent´s chosen car brand should have; iii) identify the main reason why respondents focus on preferred car brands. The correlation of these factors was tested on a sample of 2002 respondents from the Slovak republic. The analysed data represent a partial result of an extensive survey. The chosen mathematical-statistical methods such as correlation analysis and testing of statistical hypotheses were applied to fulfil the purpose of the research. Based on a survey, the most influential car brands include Skoda and Volkswagen. Especially the Skoda brand has a significant position in Slovakia, given by tradition, history and place of production of these cars.

Singular fibers of very general Lagrangian fibrations

Let [Formula: see text] be a (holomorphic) Lagrangian fibration that is very general in the moduli space of Lagrangian fibrations. We conjecture that the singular fibers in codimension one must be semistable degenerations of abelian varieties. We prove a partial result towards this conjecture, and describe an example that provides further evidence.

Analysis of the Effects of Economic Policy on Car Demand in Indonesia

This study is aims to analyze and to find out the impact of economy policy for demand for cars in Indonesia. The variables consist of this study such as GDP per kapita, lenght of road, price of BBM, interest rate for credit consumption and demand for cars. This study use the secondary data through Badan Pusat Statistik analyzed by multiple linear regression and Eviews 8 program. The results showed that R Square value of 0.994, which means that 99% of demand for cars is jointly influenced by variables in the model. While the remaining is influenced by other factors outside the model. The partial result shows the GDP per kapita has not affect, lenght of road give a positive affect and significant, price BBM give a positive affect and significant, and interest rate of credit consumption has not affect to demand for cas in Indonesia during the periode of this study

Specifications for Test Modules in the APVV Project PP-20-COVID-0002 Aerosol

The global pandemic of COVID-19 has forced the international community to look for relevant solutions to eliminate the negative effects and reduce the risks of contamination of people with this virus. The research team of the Technical University in Košice, with the support of experts and an application guarantor, BovaCHEM, approached the search for a partial solution within the applied research of a new chemical for decontamination and disinfection of surfaces that may be a source of COVID-19 threat to humans when handling packaging. ) in different conditions. The article presents a partial result of the analytical work within the project, identification and description of specifications for the creation of test modules in the project, for the subsequent verification of the pilot version of the new chemical and its further research to achieve the main goal of the project. The output of the content analysis of the issue, the examination of the patent solution at present, is the synthesis of knowledge, which is reflected in the proposed specifications for test modules and thus for further scientific work according to the approved project APVV until the end of 2021.

Nonphosphorylatable PEA15 mutant inhibits epithelial-mesenchymal transition in triple-negative breast cancer partly through the regulation of IL-8 expression

Background Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype that lacks targeted therapies. Patients with TNBC have a very poor prognosis because the disease often metastasizes. New treatment approaches addressing drivers of metastasis and tumor growth are crucial to improving patient outcomes. Developing targeted gene therapy is thus a high priority for TNBC patients. PEA15 (phosphoprotein enriched in astrocytes, 15 kDa) is known to bind to ERK, preventing ERK from being translocated to the nucleus and hence blocking its activity. The biological function of PEA15 is tightly regulated by its phosphorylation at Ser104 and Ser116. However, the function and impact of phosphorylation status of PEA15 in the regulation of TNBC metastasis and in epithelial-to-mesenchymal transition (EMT) are not well understood. Methods We established stable cell lines overexpressing nonphosphorylatable (PEA15-AA) and phospho-mimetic (PEA15-DD) mutants. To dissect specific cellular mechanisms regulated by PEA15 phosphorylation status, we performed RT-PCR immune and metastasis arrays. In vivo mouse models were used to determine the effects of PEA15 phosphorylation on tumor growth and metastasis. Results We found that the nonphosphorylatable mutant PEA15-AA prevented formation of mammospheres and expression of EMT markers in vitro and decreased tumor growth and lung metastasis in in vivo experiments when compared to control, PEA15-WT and phosphomimetic PEA15-DD. However, phosphomimetic mutant PEA15-DD promoted migration, mesenchymal marker expression, tumorigenesis, and lung metastasis in the mouse model. PEA15-AA-mediated inhibition of breast cancer cell migratory capacity and tumorigenesis was the partial result of decreased expression of interleukin-8 (IL-8). Further, we identified that expression of IL-8 was possibly mediated through one of the ERK downstream molecules, Ets-1. Conclusions Our results show that PEA15 phosphorylation status serves as an important regulator for PEA15’s dual role as an oncogene or tumor suppressor and support the potential of PEA15-AA as a therapeutic strategy for treatment of TNBC.

Characterization of the dissipative structure for the symmetric hyperbolic system with non-symmetric relaxation

This paper is concerned with the dissipative structure for the linear symmetric hyperbolic system with non-symmetric relaxation. If the relaxation matrix of the system has symmetric property, Shizuta and Kawashima in 1985 introduced the suitable stability condition called Classical Stability Condition in this paper, and Umeda, Kawashima and Shizuta in 1984 analyzed the dissipative structure of the standard type. On the other hand, Ueda, Duan and Kawashima in 2012 and 2018 focused on the system with non-symmetric relaxation, and got the partial result which is the extension of known results. Furthermore, they argued the new dissipative structure called the regularity-loss type. In this situation, our purpose of this paper is to extend the stability theory introduced by Shizuta and Kawashima in 1985 and Umeda, Kawashima and Shizuta in 1984 for our general system.