The bacteriohopanepolyol inventory of novel aerobic methane oxidising bacteria reveals new biomarker signatures of aerobic methanotrophy in marine systems

Aerobic methane oxidation (AMO) is one of the primary biologic pathways regulating the amount of methane (CH4) released into the environment. AMO acts as a sink of CH4, converting it into carbon dioxide before it reaches the atmosphere. It is of interest for (paleo)climate and carbon cycling studies to identify lipid biomarkers that can be used to trace AMO events, especially at times when the role of methane in the carbon cycle was more pronounced than today. AMO bacteria are known to synthesise bacteriohopanepolyol (BHP) lipids. Preliminary evidence pointed towards 35-aminobacteriohopane-30,31,32,33,34-pentol (aminopentol) being a characteristic biomarker for Type I methanotrophs. Here, the BHP compositions were examined for species of the recently described novel Type I methanotroph bacterial genera Methylomarinum and Methylomarinovum, as well as for a novel species of a Type I Methylomicrobium. Aminopentol was the most abundant BHP only in Methylomarinovum caldicuralii, while Methylomicrobium did not produce aminopentol at all. In addition to the expected regular aminotriol and aminotetrol BHPs, novel structures tentatively identified as methylcarbamate lipids related to C-35 amino-BHPs (MCBHPs) were found to be synthesised in significant amounts by some AMO cultures. Subsequently, sediments and authigenic carbonates from methane-influenced marine environments were analysed. Most samples also did not contain significant amounts of aminopentol, indicating that aminopentol is not a useful biomarker for marine aerobic methanotophic bacteria. However, the BHP composition of the marine samples do point toward the novel MC-BHPs components being potential new biomarkers for AMO

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table

Neutrinos in a gravitational background: a test for the universality of the gravitational interaction

In this work we propose an extended formulation for the interaction between neutrinos and gravitational fields. It is based on the parametrized post-Newtonian aproach, and includes a violation of the universality of the gravitational interaction which is non diagonal in the weak flavor space. We find new effects that are not considered in the standard scenario for violation of the equivalence principle. They are of the same order as the effects produced by the Newtonian potential, but they are highly directional dependent and could provide a very clean test of that violation. Phenomenological consequences are briefly discussed.Comment: 18 pages, revtex, no figure

Stepping across the line: Information sharing, truth-telling and the role of the personal carer in the Australian Nursing Home

The author draws on an Australian study using multiple qualitative methods to investigate truth telling in aged care. Thematic analysis of data from five nursing homes involving 23 personal care assistants revealed participants’ role understanding as influencing their perceptions about truth telling in practice. Five themes emerged: role as the happy comfort carer, division of labor, division of disclosure, role tension and frustration, and managing the division of disclosure. Role emphasis on comfort and happiness and a dominant perception that telling the truth can cause harm mean that disclosure will be withheld, edited, or partial. Participants’ role understanding divides labor and disclosure responsibility between the personal carer and registered nurse. Personal carers’ strategies for managing the division of disclosure include game playing, obfuscation, lying (denial), and the use of nonverbals. These perceptions about personal carer role, information sharing, and truth telling are paramount for understanding and improving nursing home eldercare

Реализация интегративного подхода при изучении дисциплины "Патологическая физиология" в медицинском университете

МЕДИЦИНСКИЕ ВУЗЫМЕДИЦИНСКИЕ ИНСТИТУТЫОБРАЗОВАНИЕ МЕДИЦИНСКОЕПЕДАГОГИЧЕСКИЕ ТЕХНОЛОГИИОБРАЗОВАТЕЛЬНЫЙ ПРОЦЕССУЧЕБНЫЕ ДИСЦИПЛИНЫМЕЖДИСЦИПЛИНАРНЫЕ СВЯЗИМЕЖДИСЦИПЛИНАРНАЯ ИНТЕГРАЦИЯИНТЕГРАТИВНЫЙ ПОДХОДПАТОФИЗИОЛОГИЯ (ДИСЦИПЛИНА)ПАТОЛОГИЧЕСКАЯ ФИЗИОЛОГИЯ (ДИСЦИПЛИНА)ОБУЧЕНИЕ /МЕТОДЫПРЕПОДАВАНИЕМОТИВАЦИ