The remarks on the four colors problem

In this note we are proving the four conjecture for planar graphs. The proof  follows the Euler Indentity for planar graphs

Social responsibility indices as a method of measuring corporate CSR activities

W ostatnich latach zauważalny jest wzrost znaczenia koncepcji społecznej odpowiedzialności biznesu (corporate social responsibility – CSR) w przestrzeni gospodarczej. W związku z tym coraz większym powodzeniem wśród inwestorów cieszą się narzędzia pozwalające ocenić działalność spółek pod kątem ich społecznej odpowiedzialności. Szczególne znaczenie sprawozdawczości w tym zakresie jest zauważalne po ostatnim kryzysie finansowym, który nadszarpnął zaufanie na rynku globalnym. Wychodząc naprzeciw oczekiwaniom inwestorów, instytucje finansowe publikują indeksy społecznej odpowiedzialności. Obecnie funkcjonuje kilkadziesiąt indeksów giełdowych tworzonych zgodnie z kryteriami CSR, a wśród nich najpopularniejsze to Dow Jones Sustainability Index oraz FTSE4GOOD Index, a także pierwszy w Europie Środkowo-Wschodniej – RESPECT Index. Przedsiębiorstwa coraz chętniej wdrażają rozwiązania z zakresu CSR i chętnie zgłaszają się do indeksów społecznej odpowiedzialności. Niestety mimo dużej świadomości istnienia indeksów nie są one kluczowym kryterium branym pod uwagę przy podejmowaniu decyzji inwestycyjnych przez uczestników rynku.The recent years have seen a noticeable increase in the importance of corporate social responsibility (CSR) concepts in the business environment. As a result, the demand for tools measuring corporate social responsibility has been growing. Investors, too started to realise the particular importance of reporting which became apparent after the recent financial crisis that had significantly diminished the trust in the global market. In response to investors’ expectations, financial institutions today publish indices of social responsibility. Currently, there are dozens of stock indexes based on CSR criteria, including the most popular Dow Jones Sustainability Index and the FTSE4GOOD Index, as well as RESPECT Index, the first CSR index in Central and Eastern Europe. Companies are increasingly frequently willing to implement CSR solutions and they also apply for inclusion in social responsibility indices. However, despite the high awareness of the existence of such indexes, they are not recognised by market participants as a key criterion to be used when making investment decisions

Analysis, Design and Realization of Software Process Simulation Tool

Import 05/08/2014Moderní doba žádá moderní přístup k vývoji aplikací. Pomoci nám mohou softwarové prostředky, které umožňují podpořit vývoj aplikací přesnou definicí a následnou správou softwarového procesu. Díky těmto prostředkům jsme schopni proces jednoduše vymodelovat, odsimulovat daný model a použít výsledky simulace k analýze modelu procesu (jeho efektivity, správnosti). Tato diplomová práce se zabývá kompletní realizací právě takového softwarového nástroje. Cílem diplomové práce je představení jednotlivých modelovacích a simulačních metod a jejich následné zhodnocení. Vybrané metody budou poté implementovány v rámci výše zmíněného softwarového nástroje. V závěru budou k dispozici výsledky simulací předem vymodelovaných ukázkových procesů.Modern times asks modern approaches towards application development. We can benefit from using software tools which can support application development by modeling and managing our software processes. Thanks to these tools we are able to seamlessly model and simulate model of a process and then use the simulation results to analyze the model (its efficiency, correctness). This diploma thesis deals with complete realization of such software tool. The goal of the thesis is to introduce individual modeling a simulation methods and evaluate them. Chosen methods will be implemented as part of the above mentioned software tool. There will be results of simulations of beforehand modeled sample processes available in the conclusion.460 - Katedra informatikyvýborn

Insight into the reaction of alexidine with sodiumhypochlorite : a potential error in endodontic treatment

Therapeutic success in endodontic treatment depends on successful infection control. Alexidine dihydrochloride (ALX) was recently proposed as a potential alternative to 2% chlorhexidine (CHX) as it possesses similar antimicrobial properties, expresses substantivity and does not produce p-chloroaniline (PCA) when mixed with sodium hypochlorite (NaOCl). However, the products released in this reaction have not been described to date. The aim of this study was to identify detected chemical compounds formed in the reaction of ALX and NaOCl with the ultra-high-performance liquid chromatography–mass spectrophotometry (UHPLC-MS) method and assess whether precipitates and PCA are formed in this reaction. Solutions of ALX were mixed with the equivalent volume of 2% and 5.25% (w/v) NaOCl solutions. As control, 2% (w/v) CHX was mixed with 2% and 5.25% (w/v) NaOCl. Samples were subjected to the UHPLC-MS analysis. The mixture of ALX and NaOCl resulted in a yellowish precipitate formation, the amount of which depended on NaOCl concentration. Interaction of ALX and NaOCl resulted in the production of aliphatic amines. No PCA was formed when NaOCl was mixed with ALX. However, for the first time, we identified the possible products of the interaction. The interaction between NaOCl and ALX results in the formation of aliphatic amines; therefore, these compounds should not be mixed during endodontic treatment

CD73 Is Critical for the Resolution of Murine Colonic Inflammation

CD73 is a glycosyl-phosphatidylinositol-(GPI-) linked membrane protein that catalyzes the extracellular dephosphorylation of adenosine monophosphate (AMP) to adenosine. Adenosine is a negative regulator of inflammation and prevents excessive cellular damage. We investigated the role of extracellular adenosine in the intestinal mucosa during the development of Dextran-Sulfate-Sodium-(DSS-)salt-induced colitis in mice that lack CD73 (CD73−/−) and are unable to synthesize extracellular adenosine. We have found that, compared to wild-type (WT) mice, CD73−/− mice are highly susceptible to DSS-induced colitis. CD73−/− mice exhibit pronounced weight loss, slower weight recovery, an increase in gut permeability, a decrease in expression of tight junctional adhesion molecules, as well as unresolved inflammation following the removal of DSS. Moreover, colonic epithelia in CD73−/− mice exhibited increased TLR9 expression, high levels of IL-1β and TNF-α, and constitutive activation of NF-κB. We conclude that CD73 expression in the colon is critical for regulating the magnitude and the resolution of colonic immune responses.National Institutes of Health (U.S.) (grant A1072434-A2)National Institutes of Health (U.S.) (grant R01NS063011

Myeloid Cell Sirtuin-1 Expression Does Not Alter Host Immune Responses to Gram-Negative Endotoxemia or Gram-Positive Bacterial Infection

The role of sirtuin-1 (SIRT1) in innate immunity, and in particular the influence of SIRT1 on antimicrobial defense against infection, has yet to be reported but is important to define since SIRT1 inhibitors are being investigated as therapeutic agents in the treatment of cancer, Huntington’s disease, and autoimmune diseases. Given the therapeutic potential of SIRT1 suppression, we sought to characterize the role of SIRT1 in host defense. Utilizing both pharmacologic methods and a genetic knockout, we demonstrate that SIRT1 expression has little influence on macrophage and neutrophil antimicrobial functions. Myeloid SIRT1 expression does not change mortality in gram-negative toxin-induced shock or gram-positive bacteremia, suggesting that therapeutic suppression of SIRT1 may be done safely without suppression of myeloid cell-specific immune responses to severe bacterial infections.American Asthma Foundation (Stephen Silberstein Senior Fellowship Awards

Transcriptional Responses of Different Brain Cell Types to Oxygen Decline

Brain hypoxia is associated with a wide range of physiological and clinical conditions. Although oxygen is an essential constituent of maintaining brain functions, our understanding of how specific brain cell types globally respond and adapt to decreasing oxygen conditions is incomplete. In this study, we exposed mouse primary neurons, astrocytes, and microglia to normoxia and two hypoxic conditions and obtained genome-wide transcriptional profiles of the treated cells. Analysis of differentially expressed genes under conditions of reduced oxygen revealed a canonical hypoxic response shared among different brain cell types. In addition, we observed a higher sensitivity of neurons to oxygen decline, and dissected cell type-specific biological processes affected by hypoxia. Importantly, this study establishes novel gene modules associated with brain cells responding to oxygen deprivation and reveals a state of profound stress incurred by hypoxia

Hif-2α-Dependent Induction of miR-29a Restrains TH1 Activity During T Cell Dependent Colitis

Metabolic imbalance leading to inflammatory hypoxia and stabilization of hypoxia-inducible transcription factors (HIFs) is a hallmark of inflammatory bowel diseases. We hypothesize that HIF could be stabilized in CD4+ T cells during intestinal inflammation and alter the functional responses of T cells via regulation of microRNAs. Our assays reveal markedly increased T cell-intrinsic hypoxia and stabilization of HIF protein during experimental colitis. microRNA screen in primary CD4+ T cells points us towards miR-29a and our subsequent studies identify a selective role for HIF-2α in CD4-cell-intrinsic induction of miR-29a during hypoxia. Mice with T cell-intrinsic HIF-2α deletion display elevated T-bet (target of miR-29a) levels and exacerbated intestinal inflammation. Mice with miR-29a deficiency in T cells show enhanced intestinal inflammation. T cell-intrinsic overexpression of HIF-2α or delivery of miR-29a mimetic dampen TH1-driven colitis. In this work, we show a previously unrecognized function for hypoxia-dependent induction of miR-29a in attenuating TH1-mediated inflammation