36 research outputs found
Paradigma of Democracy in 20th Century
Diplomová práce "Paradigma demokracie ve 20. století" pojednává o moderních teoriích demokracie. Na základě čtyř novodobých teorií demokracie, které vznikly v průběhu 20. století, se tato práce snaží dokázat rozdílnost ve výkladu pojmu demokracie. Diplomová práce popisuje následující teorie: konkurenční demokracie J. A. Schumpetera; pluralitní demokracie a polyarchie R. A. Dahla; teorii spravedlnosti J. Rawlse. V závěru práce je provedena stručná komparace hlavních myšlenek zmíněných demokratických teorií, která má dokázat rozdílné výklady pojmu demokracie, respektive dokázat, že demokracie není zcela jednoznačným pojmem, jak by se na první pohled mohlo jevit. Je tedy třeba chápat "teorii demokracie" jako velice široké spektrum různých pojetí demokracie, která jsou často názorově protichůdná. Powered by TCPDF (www.tcpdf.org)Diploma thesis "Paradigma of Democracy in 20th. century" dissert upon modern theory of democracy. Thesis try to point differences in interpretation of the democracy conception on the basis of four modern theory democracy, which were interpreted in 20th century. Diploma thesis describe these doctrines: theory of competition democracy by J. A. Schumpeter; theory of pluralistic democracy and theory of polyarchy by R. A. Dahl; theory of justice by J. Rawls. At the close of thesis is short comparative analysis based on the main ideas these four democratic theory. Comparative analysis try to demonstrate main differences in the interpretation of democracy idea. It is necessary to understand, that "democracy" ins't exactly single valued definition, but democracy is wide spectrum of various doctrines. These various doctrines have very often divergencies of opinion about democracy. Powered by TCPDF (www.tcpdf.org)Department of Political ScienceKatedra politologieFaculty of Social SciencesFakulta sociálních vě
Abdominal Aortic Aneurysm and Malignancies
Concomitant AAA and abdominal malignancy are always very complicated conditions requiring early management of both pathologies. This is undoubtedly a dilemma for a surgeon who cannot currently rely on any large randomized trials or mandatory guidelines. When making decisions, a surgeon most often relies on personal experience, the experience of his/her center and/or limited literary guidelines and recommendations. Efforts should be aimed at achieving a consensual multidisciplinary decision about which pathology requires “more acute” management. The decision-making process is easier if one of the pathologies is life-threatening, and such pathology should be managed first. In most cases, however, AAA is asymptomatic and a malignancy is found randomly, as a secondary finding during the follow-up of AAA patients, or vice versa, AAA is found randomly during the staging of cancer patients. In these cases, the therapeutic algorithm already admits several possible variants. Endovascular repair of AAA (EVAR) resulted in an absolute change in the management of these patients. EVAR can be used in simultaneous or stage procedures with minimal time delay. Also, surgical open resection is an option (simultaneously or staged). It is necessary to know the advantages and risks of all approaches
Orbiting pairs of walking droplets: Dynamics and stability
A decade ago, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006)]PRLTAO0031-900710.1103/PhysRevLett.97.154101 discovered that a millimetric droplet sustained on the surface of a vibrating fluid bath may self-propel through a resonant interaction with its own wave field. We here present the results of a combined experimental and theoretical investigation of the interactions of such walking droplets. Specifically, we delimit experimentally the different regimes for an orbiting pair of identical walkers and extend the theoretical model of Oza [J. Fluid Mech. 737, 552 (2013)] JFLSA70022-112010.1017/jfm.2013.581 in order to rationalize our observations. A quantitative comparison between experiment and theory highlights the importance of spatial damping of the wave field. Our results also indicate that walkers adapt their impact phase according to the local wave height, an effect that stabilizes orbiting bound states.National Science Foundation (U.S.) (Grant CMMI-1333242)National Science Foundation (U.S.) (Grant DMS-1614043
Ventilation and Haemodynamic Indicators in Spontaneously Breathing Pigs under General Anaesthesia
Wettability-independent bouncing on flat surfaces mediated by thin air films
The impingement of drops onto solid surfaces1, 2 plays a crucial role in a variety of processes, including inkjet printing, fog harvesting, anti-icing, dropwise condensation and spray coating3, 4, 5, 6. Recent efforts in understanding and controlling drop impact behaviour focused on superhydrophobic surfaces with specific surface structures enabling drop bouncing with reduced contact time7, 8. Here, we report a different universal bouncing mechanism that occurs on both wetting and non-wetting flat surfaces for both high and low surface tension liquids. Using high-speed multiple-wavelength interferometry9, we show that this bouncing mechanism is based on the continuous presence of an air film for moderate drop impact velocities. This submicrometre ‘air cushion’ slows down the incoming drop and reverses its momentum. Viscous forces in the air film play a key role in this process: they provide transient stability of the air cushion against squeeze-out, mediate momentum transfer, and contribute a substantial part of the energy dissipation during bouncing
Hormone receptor conversion in metastatic breast cancer
Background/Objective: Hormone receptor (HR) status is one of the key factors in determining the treatment of breast cancer. Previous studies suggested that HR status may change in metastatic tissue. However, available studies focused mainly on primary biopsies and there are only few trials comparing HR status in the primary tumour and the metastasis using material from complete resection. The aim of the study was to determine the frequency of HR alterations in metastatic breast cancer.
Materials and methods: The study retrospectively examines a total of 50 patients who underwent brain, lung, or liver metastasectomy for metastatic breast cancer between January 2000 and January 2019.
Results: HR conversion was observed in a total of 30 cases (60.0%), while HER-2/neu (human epidermal growth factor receptor 2) discrepancy surprisingly occurred only in one case (2.0%). A change in immunophenotype occurred in 28% of cases. Triple-negativity was more frequent in brain metastases (p = 0.039).
Conclusions: We have confirmed that HR conversion between the primary tumour and its metastases occurs in a significant number of cases, which has important implications for further treatment decisions
VPN implementation comparison in terms of safety
VPN se dá dosáhnout použitím různých kryptografických protokolů. Ty se mohou lišit principy fungování nebo používanými kryptografickými algoritmy. Cílem práce bylo nastudovat kryptografické protokoly a porovnat je na základě nabízených bezpečnostních služeb (důvěrnost dat, integrita dat, autentizace apod.) a veřejně publikovaných bezpečnostních zranitelností a následně nabídnout doporučení pro implementaci VPN. Konkrétně se jednalo o protokoly PPTP, IPsec, L2TP, TLS 1.2 a SSHv2. PPTP by se nemělo používat kvůli absenci autentizace paketu, zranitelným autentizačním algoritmům (PAP, CHAP) a vazbě na prolomenou šifru RC4. Ostatní zmíněné protokoly lze doporučit, avšak pouze při vyhnutí se určitým konfiguracím. Konkrétně u IPsec se vyhnout protokolu AH, který neumí zaručit důvěrnost dat. Není vhodná ani jeho kombinace s ESP kvůli nižšímu výkonu a možnosti zranitelné posloupnosti MAC-then-encrypt. Tunelovací protokol L2TP nesmí být použit sám o sobě, ale pouze v kombinaci s bezpečnostním protokolem, ideálně IPsec. U protokolů TLS a SSH existují zranitelnosti vyplývající z jejich implicitních používaných posloupností, a to MAC-then-encrypt (TLS) a encrypt-and-MAC (SSH). Doporučil jsem používat posloupnost encrypt-then-MAC, kterou pro TLS jako rozšíření definuje RFC 7366 a u SSH je věcí podpory implementace (např. OpenSSH 7.3). Na rozdíl od IPsec a TLS, není v SSH doporučeno používat šifrovací CBC mód, ale upřednostnit CTR mód. IPsec, TLS a SSH se dají použít i s AEAD algoritmy, které provádějí šifrování a autentizaci paketu v jednom kroku a odpadají tak rizika zranitelností vzniklé z důvodu časového nesouladu mezi šifrováním a výpočtu hodnoty MAC. Pro výměnu klíčů je dobré použít efemerální algoritmy Diffie-Helmann (DHE, ECDHE) kvůli schopnosti zajistit Perfect Forward Secrecy. VPN postavené na IPsec, L2TP/IPsec a TLS jsem doporučil do větších prostředí kvůli podpoře uživatelských certifikátů, což platí i pro představené řešení OpenVPN. SSH VPN je pak vhodné do menších prostředí z důvodu problematické podpory certifikátů a rozšířenému používání veřejných klíčů, což zvyšuje nároky na jejich správu. Obecné doporučení pro implementace je podpora čipových karet k uložení certifikátu nebo autentizace oproti autentizačnímu serveru RADIUS.VPN is achieved using different cryptographic protocols. These may vary in functional principles or cryptographic algorithms. The aim of this bachelor thesis is to study cryptographic protocols and compare them based on offered security services and published security vulnerabilities and subsequently offer recommendations for VPN implementation. The protocols mentioned are PPTP, IPsec, L2TP, TLS 1.2 and SSHv2. PPTP should not be used due to absence of packet authentication, vulnerable authentication algorithms (PAP, CHAP) and broken RC4 cipher. The other mentioned protocols can be recommended but only when avoiding certain configurations. As for IPsec, it is needed to avoid using AH protocol only that cannot guarantee the data confidentiality. Also, its combination with ESP is not suitable due to lower performance and possibility of vulnerable MAC-then-encrypt approach. The L2TP protocol should be used only in combination with security protocol like IPsec. As for TLS and SSH, there are vulnerabilities resulting from their implicit sequencing, MAC-then-encrypt (TLS) and encrypt-and-MAC (SSH). I recommend using the encrypt-then-MAC sequence for TLS and SSH. SSH is not recommended to use with CBC encryption mode. It is recommended to use CTR mode. IPsec, TLS, and SSH can also be used with AEAD ciphers that can encrypt and authenticate the packet in one step. Diffie-Helmann ephemeral algorithms (DHE, ECDHE) are recommended for key exchange, due to their ability to provide Perfect Forward Secrecy (PFS). I recommended IPsec, L2TP/IPsec, and TLS VPN solutions to deploy in large environments due to support user certificates. SSH VPN is therefore suitable for smaller environments due to problematic certificates support and widespread use of public keys. The general recommendation is to support smart cards to store a certificate or user authentication against the RADIUS authentication server
Unit testing options for Oracle DBMS applications
This diploma thesis deals with unit testing of applications implemented in PL/SQL programming language. It assumes that Oracle PL/SQL programs have certain specifics, which result in specific requirements for unit testing frameworks. The ambition of this work is to find out what support for unit testing can PL/SQL developers expect from unit testing frameworks today. Furthermore, to compile the available knowledge in this area and to design a general model of attributes and requirements for unit testing framework for PL/SQL applications. The work first presents the specifics of application development in PL/SQL and then introduces requirements that arises for testing. Based on them, a model of general attributes of unit testing framework is compiled, which considers testing with database and the xUnit standard. Attributes are then evaluated for three selected solutions, which are composed of utPLSQL, JUnit, DbUnit, Database Rider and JDBDT frameworks. These solutions are compared. The selection and evaluation procedure are based on the CASE instrument evaluation process defined by the IEEE 14102-2010 standard.Tato diplomová práce se zabývá jednotkovým testováním při vývoji aplikací v programovacím jazyce PL/SQL. Vychází z předpokladu, že vývoj aplikací v prostředí databázového systému Oracle má určitá specifika, ze kterých vyplývají i specifické nároky na nástroje jednotkového testování. Ambicí práce bylo zjistit, jakou podporu jednotkového testování svého kódu mohou dnes vývojáři v jazyce PL/SQL od testovacích frameworků a nástrojů očekávat. Dále pak poskládat dostupné znalosti v této oblasti a navrhnout obecný model atributů a požadavků na testovací nástroj pro PL/SQL aplikace. V práci jsou nejdříve představena specifika vývoje v PL/SQL a následně nároky, které z nich plynou pro testování. Na jejich základě je sestaven model obecných atributů testovacího nástroje, který zohledňuje jednak testování s databází a jednak standard xUnit. Atributy jsou následně hodnoceny u tří vybraných řešení, která jsou složena z frameworků utPLSQL, JUnit, DbUnit, Database Rider a JDBDT. Tato řešení jsou následně porovnána. Postup výběru a hodnocení je založen na procesu pro hodnocení CASE nástrojů definovaným standardem IEEE 14102-2010