Giant adsorption of microswimmers: duality of shape asymmetry and wall curvature

The effect of shape asymmetry of microswimmers on their adsorption capacity at confining channel walls is studied by a simple dumbbell model. For a shape polarity of a forward-swimming cone, like the stroke-averaged shape of a sperm, extremely long wall retention times are found, caused by a non-vanishing component of the propulsion force pointing steadily into the wall, which grows exponentially with the self-propulsion velocity and the shape asymmetry. A direct duality relation between shape asymmetry and wall curvature is proposed and verified. Our results are relevant for the design microswimmer with controlled wall-adhesion properties. In addition, we confirm that pressure in active systems is strongly sensitive to the details of the particle-wall interactions.Comment: 6 pages, 7 figure

Hydrodynamic simulations of self-phoretic microswimmers

A mesoscopic hydrodynamic model to simulate synthetic self-propelled Janus particles which is thermophoretically or diffusiophoretically driven is here developed. We first propose a model for a passive colloidal sphere which reproduces the correct rotational dynamics together with strong phoretic effect. This colloid solution model employs a multiparticle collision dynamics description of the solvent, and combines potential interactions with the solvent, with stick boundary conditions. Asymmetric and specific colloidal surface is introduced to produce the properties of self-phoretic Janus particles. A comparative study of Janus and microdimer phoretic swimmers is performed in terms of their swimming velocities and induced flow behavior. Self-phoretic microdimers display long range hydrodynamic interactions and can be characterized as pullers or pushers. In contrast, Janus particles are characterized by short range hydrodynamic interactions and behave as neutral swimmers. Our model nicely mimics those recent experimental realization of the self-phoretic Janus particles.Comment: 11pages, 12figures, 2table

Ontologiczne podstawy edukacji religijnej w chrześcijaństwie

oai:ojs.pressto.amu.edu.pl:article/5779The article indicates ontological bases which are at the ground of the religious education in Christianity. The touched problem considers issues of Christian anthropology and concerns the category of the person. The definite concept of the man forejudges applied pedagogic manners, that is the way of the approach to the pupil. The characteristics of the person indicates that for purposes of efforts of the man is his salvation, that in Christianity is the achievement of Communion with God, therefore the Christian religious education in its message points soteriological goals and measures. However nowadays, pluralism and multiculturalism and conditions of the public school extort using such type of the religious education which on one hand will accomplish ontological premises of Christian anthropology and on the other hand requirements of the present day

Cooperative Motion of Active Brownian Spheres in Three-Dimensional Dense Suspensions

The structural and dynamical properties of suspensions of self-propelled Brownian particles of spherical shape are investigated in three spatial dimensions. Our simulations reveal a phase separation into a dilute and a dense phase, above a certain density and strength of self-propulsion. The packing fraction of the dense phase approaches random close packing at high activity, yet the system remains fluid. Although no alignment mechanism exists in this model, we find long-lived cooperative motion of the particles in the dense regime. This behavior is probably due to an interface-induced sorting process. Spatial displacement correlation functions are nearly scale-free for systems with densities close to or above the glass transition density of passive systems.Comment: 6 pages, 7 figure

Preventing congenital toxoplasmosis — implementation of clinical practice guidelines

 Objectives: The aim of the study was to evaluate obstetric care of pregnant women with regard to prevention of congenital toxoplasmosis. Additionally, we attempted to determine the frequency of markers for past infection with Toxoplasma gondii in order to characterize the current significance of preventive measures in the Polish population. Material and methods: The analysis of the medical records — pregnancy charts of women who presented for delivery — was performed. Patient age, place of residence, and toxoplasmosis test (or lack of it) were evaluated. Also, further diagnostic management, depending on the serologic result, was investigated. Results: Out of 670 pregnant women, 628 (93.73%) underwent at least one toxoplasmosis diagnostic test. Out of those, 502 (73%) had a negative result (IgG –, IgM –), and 2 (0.32%) had a positive result (IgG +, IgM +), while history of infection with Toxoplasma gondii was confirmed (IgG +, IgM –) in 124 (19.75%) cases. Repeat testing was required in 183 (29.14%) out of the 628 women. Conclusions: A high rate of women in whom IgG antibodies were not detected in the first test and a low rate of women who required repeat testing later in pregnancy are noteworthy. Regardless of the healthcare policy, parents should receive reliable information about the nature of the disease and possibilities of prevention, while medical professionals ought to have easy access to research data about the epidemiologic status and recommendations

Mistycyzm buddyzmu tybetańskiego – charakterystyka Drogi Wglądu

Wysocki Adam, Mysticism in Tibetan Buddhism. A study into the Path of Insight. Culture – Society – Education no 2(16) 2019, Poznań 2019, pp. 183–201, Adam Mickiewicz University Press. ISSN 2300-0422. DOI 10.14746/kse.2019.16.12. The Path of Insight is a spiritual path of Tibetan Buddhism tradition. The fundamental part consists of three elements, such like: preliminary practices, the tranquility meditation and the penetrating insight meditation. However, counted three parts one ought to perceive as aspects of one process aiming to realize of the soteriology purpose. The achievement of the non-dual state has its own development process, which consists experience of the non-dual state, stabilise it and then development of it. Outline of development process is contained in the Path o Insight and relies on exceeding of subjective-objective divisibility. It isperceived as an effect of the ignorance of true nature of the individual. The achievement of the non-dual state, that is nature of the mind (tib. sems nyid) constitutes the purpose of the Path of Insight and it is described by concept-symbol called mahamudra.Wysocki Adam, Mysticism in Tibetan Buddhism. A study into the Path of Insight. Culture – Society – Education no 2(16) 2019, Poznań 2019, pp. 183–201, Adam Mickiewicz University Press. ISSN 2300-0422. DOI 10.14746/kse.2019.16.12. The Path of Insight is a spiritual path of Tibetan Buddhism tradition. The fundamental part consists of three elements, such like: preliminary practices, the tranquility meditation and the penetrating insight meditation. However, counted three parts one ought to perceive as aspects of one process aiming to realize of the soteriology purpose. The achievement of the non-dual state has its own development process, which consists experience of the non-dual state, stabilise it and then development of it. Outline of development process is contained in the Path o Insight and relies on exceeding of subjective-objective divisibility. It isperceived as an effect of the ignorance of true nature of the individual. The achievement of the non-dual state, that is nature of the mind (tib. sems nyid) constitutes the purpose of the Path of Insight and it is described by concept-symbol called mahamudra