Elementary Intracellular Ca Signals approximated as a Transition of Release Channel System from a Metastable State

Cardiac muscle contraction is initiated by an elementary Ca signal (called Ca spark) which is achieved by collective action of Ca release channels in a cluster. The mechanism of this synchronization remains uncertain. We approached Ca spark activation as an emergent phenomenon of an interactive system of release channels. We constructed a weakly lumped Markov chain that applies an Ising model formalism to such release channel clusters and probable open channel configurations and demonstrated that spark activation is described as a system transition from a metastable to an absorbing state, analogous to the pressure required to overcome surface tension in bubble formation. This yielded quantitative estimates of the spark generation probability as a function of various system parameters. We performed numerical simulations to find spark probabilities as a function of sarcoplasmic reticulum Ca concentration, obtaining similar values for spark activation threshold as our analytic model, as well as those reported in experimental studies. Our parametric sensitivity analyses also showed that the spark activation threshold decreased as Ca sensitivity of RyR activation and RyR cluster size increased

The quality of student training of psychologists In the federal internet exam

This article discusses the results of the use of different criteria for assessing the results of computer testing to determine quality student training of psychologists in general educational subjectsВ статье рассматриваются результаты применения разных критериев оценки результатов компьютерного тестирования для определения качества подготовки студентов направления подготовки «Психология» по общеобразовательным предмета

Singly generated quasivarieties and residuated structures

A quasivariety K of algebras has the joint embedding property (JEP) iff it is generated by a single algebra A. It is structurally complete iff the free countably generated algebra in K can serve as A. A consequence of this demand, called "passive structural completeness" (PSC), is that the nontrivial members of K all satisfy the same existential positive sentences. We prove that if K is PSC then it still has the JEP, and if it has the JEP and its nontrivial members lack trivial subalgebras, then its relatively simple members all belong to the universal class generated by one of them. Under these conditions, if K is relatively semisimple then it is generated by one K-simple algebra. It is a minimal quasivariety if, moreover, it is PSC but fails to unify some finite set of equations. We also prove that a quasivariety of finite type, with a finite nontrivial member, is PSC iff its nontrivial members have a common retract. The theory is then applied to the variety of De Morgan monoids, where we isolate the sub(quasi)varieties that are PSC and those that have the JEP, while throwing fresh light on those that are structurally complete. The results illuminate the extension lattices of intuitionistic and relevance logics

Lanthanum Activity in La–U–Ga–X Systems (X = Al or In)

Lanthanum activity was determined for the first time in La–U–Ga–X (X = Al or In) alloys. Ga–In and Ga–Al alloys were taken in the eutectic composition (21.8 wt.% In and 1.6 wt.% Al, respectively). Measurements were performed between 573 and 1073 K employing the e.m.f. method. Keywords: Lanthanum; Uranium; Gallium-Indium Eutectic; Gallium-Aluminium Eutectic; Activity; Thermodynamics

The knowledge quality management based on the compilation of structurallogical schema (knowledge map)

Данная статья посвящена проблеме менеджмента знаний в образовании. Основой управленческого воздействия на процесс усвоения знаний является перевод знаний из неявных в явные, формализованные. Формализация позволяет говорить об эталоне, с которым можно сравнивать достигнутые результаты и осуществлять мониторинг результатов учебных достижений учащихся. Применение тестовых технологий позволяет получить объективную оценку уровня обученности ученика (класса), а также управлять процессом усвоения знаний.The article is devoted to the problem of knowledge management in education. The administrative action at the process of knowledge acquirement is based on the procedure of the transformation of implicit knowledge into explicit and formalized knowledge. The formalization allows to speak about the etalon, according with which the achieved results could be compared and the monitoring of the students’ progress in learning is organized. The using of the test-technologies allows to get the objective appraisal of the level of student’s knowledge (or of the grade)