Nobel Lecture, presented on December 8, 2016, at Aula Magna, Stockholm University. This article describes the history and background of three discoveries cited in this Nobel Prize: The "TKNN" topological formula for the integer quantum Hall effect found by David Thouless and collaborators, the Chern insulator of quantum anomalous Hall effect, and its role in the later discovery of time-reversal invariant topological insulators, and the unexpected topological spin-liquid state of the spin-1 quantum antiferromagnetic chain, which provided an initial example of topological quantum matter. This article summarizes how these early beginnings have led to the exciting, and currently extremely active, field of "topological matter"., F. Duncan M. Haldane ; přeložil Ivan Gregora ; foto A. Mahmoud, Odile Belmontová., and Obsahuje bibliografii
Nobel Lecture, presented on December 8, 2016, at Aula Magna, Stockholm University. In his lecture F. J. M. Kosterlitz described theoretical discoveries of topological phase transitions and topological phases of matter, partially on behalf of the main researcher behind those discoveries, David Thouless, who was not able to give the talk. First, the history of the collaboration between Kosterlitz and Thouless was briefly described. Then, a summary of their contribution to applications of topology to classical Berezinskii-Kosterlitz-Thouless of BKT phase transition was described., John Michael Kosterlitz ; přeložil Ivan Gregora ; foto A. Mahmoud., and Obsahuje bibliografii
The contribution is a continuation of [2] which deals with analytic solution of torsion of a bar with simply connected profile, i.e. profile without holes. In this paper the case of multiply connected profile, i.e. profile with holes, is studied. The stress-strain analysis leads to the Airy stress function Φ. On boundary of each hole the function Φ has prescribed an unknown constant value completed with an integral condition. The mathematical model is also derived from the variational principle.
The second part of the paper contains solutions for the ring profile and for comparison also for incomplete ring profiles including the ‘broken‘ ring profile. The results are compared in tables and pictures. and Obsahuje seznam literatury
The contribution deals with strain-stress analysis of torsion of a non-circular bar. Mathematical model is exactly derived and solutions are introduced and visualised for cases of triangular, rectangular and some other profiles. and Obsahuje seznam literatury
The objective of our study was to assess the influence of mechanical ventilation on healthy body organs. Fifteen piglets (aged 6 weeks, 19-27 kg) were anesthetized, instrumented, and divided into three groups: Group A - spontaneously breathing, group B - mechanically ventilated with tidal volume 6 ml/kg, and group C - ventilated with tidal volume 10 ml/kg for 12 hours. The parameters of lung, heart, liver and kidney functions neurohumoral regulation and systemic inflammatory reaction were recorded initially (time-1) and after 12 hours (time-12) of mechanical ventilation. At the onset of experiment (time-1) the levels of soluble adhesive molecules were higher (CAM; P<0.01), glomerular filtration index and free water clearance were lower (P<0.05) in both ventilated groups than in group A. Right ventricle myocardial performance index was higher (RIMP; P<0.05) in group C when compared with group A. Levels of CAM (P<0.05) and creatinine clearance (P<0.01) were higher, free water clearance was lower (P<0.05) in group C when compared to group B. At time-12 the RIMP (P<0.05) and levels of CAM were increased (P<0.01), creatinine clearance was decreased (P<0.05) in both ventilated groups compared to the same parameter at time-1. Ventilation index was higher (P<0.05), and hypoxemic index was lower (P<0.01) in group C when compared to group B. In conclusion, this study showed that mechanical ventilation induced changes compatible with early inflammatory response in healthy animals. Higher tidal volumes had detrimental effect on ventilatory parameters, reduced myocardial performance and potentiated adverse reaction of other organs., J. Kobr ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The present study investigated cardiac function in hearts of mice with total deficiency of the β1-, β2- and β3-adrenoceptors (TKO) in comparison to wildtype mice (WT). We investigated cardiac morphology and echocardiographic function, measured protein expression of Ca2+-regulatory proteins, SERCA 2a activity, myofibrillar function, and performed running wheel tests. Heart weight and heart-to-body weight ratio were significantly smaller in TKO as compared to WT. This was accompanied by a decrease in the size of the cardiomyocytes in TKO. Heart rate and ejection fraction were significantly diminished in TKO as compared to WT. Protein expressions of SERCA 2a, ryanodine receptor and Na+/Ca2+-exchanger were similar in TKO and WT mice, but phospholamban protein expression was increased. PKAdependent phosphorylation of phospholamban at serine 16 was absent and CaMKII-dependent phosphorylation at threonine 17 was decreased in TKO. All alterations were paralleled by a decrease in SERCA 2a-activity. A similar maximal calciumdependent tension but an increased myofibrillar calciumsensitivity was measured in TKO as compared to WT. We did not observe relevant functional impairments of TKO in running wheel tests. In the absence of β-agonistic stimulation, SERCA 2a activity is mainly regulated by alterations of phospholamban expression and phosphorylation. The decreased SERCA 2a activity following β-adrenoceptor deficiency may be partly compensated by an increased myofibrillar calcium-sensitivity., S. Lee ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
A study of displacements relating to geodynamical processes involves a use of accurate measurement equipment. Better and better accuracy of field surveys neglecting a survey environment can be insufficient in a reliable study. One of the environmental aspects is discussed in the paper. That is a geotechnical condition of a ground - an environment of benchmarks, which changes of position are observed in geodetic surveys. The conditions determine a ground stability affected by weather or geological processes. The main idea of the paper is to consider geotechnical and geological aspects in geodetic reasoning carried on the base of displacement analysis within a study of geodynamics. There are presented examples illustrating the problem. The first relates to former levelling observations carried in an area of Wieliczka, well geologically surveyed due to mining activity in a salt deposit. There are presented results obtained on the base of a numerical analysis. The seasonal variations of benchmarks’ heights are explained in a background of geology. The changes of ground properties induced by atmospheric conditions are suggested as the main cause of the displacements. The survey data processing provided values of displacements caused by seasonally expanding grounds. The second examples concerns ongoing observations in the area of Inowroclaw (located above the salt dome) bring similar variations of heights that can not be related to that cause. The estimated linear trend of height changes proves an uplift process of the salt dome. Derived conclusions suggest a certain methodology helpful in reliable analysis of geodetic surveys. The conclusions prove that geodetic surveys carried out for investigations of displacements in geodynamics require quite extensive geological data., Zbigniew Szczerbowski., and Obsahuje bibliografii
Jednotlivci mají nesmírně velké systémy modálních znalostí a domněnek - systémy toho, co a je a co není možné, a systémy toho, co je a co není nutné. Takové individualizované systémy modálních znalostí a domněnek se nazývají "modálni světy." V tomto článku se ukazuje, že modalita plyne z kauzace, že modálni "implikace" a "vyplývání" je třeba chápat jako modálni determinovanost, že modálni slovesa nefungují sama o sobě, nýbrž zároveň s jinými prostředky, že modálni znalosti lze pojednat, že existují plochy modálni stability a že některé modálni znalosti jsou explicitní a jiné implicitní. Článek uzavírá návrhem reprezentace modálních znalostí a domněnek.