Large Decrease of Fluctuations for Supercooled Water in Hydrophobic Nanoconfinement

Using Monte Carlo simulations we study a coarse­grained model of a water layer confined in a fixed disordered matrix of hydrophobic nanoparticles at different particle concentrations c. For c = 0 we find a 1st order liquid­liquid phase transition (LLPT) ending in one critical point at low pressure P. For c > 0 our simulations are consistent with a LLPT line ending in two critical points at low and high pressure. For c = 25% at high P and low temperature T we find a dramatic decrease of compressibility, thermal expansion coefficient, and specific heat. Surprisingly, the effect is present also for c as low as 2.4%. We conclude that even a small presence of nanoscopic hydrophobes can drastically suppress thermodynamic fluctuations, making the detection of the LLPT more difficult

Large Decrease of Fluctuations for Supercooled Water in Hydrophobic Nanoconfinement

Using Monte Carlo simulations we study a coarse­grained model of a water layer confined in a fixed disordered matrix of hydrophobic nanoparticles at different particle concentrations c. For c = 0 we find a 1st order liquid­liquid phase transition (LLPT) ending in one critical point at low pressure P. For c > 0 our simulations are consistent with a LLPT line ending in two critical points at low and high pressure. For c = 25% at high P and low temperature T we find a dramatic decrease of compressibility, thermal expansion coefficient, and specific heat. Surprisingly, the effect is present also for c as low as 2.4%. We conclude that even a small presence of nanoscopic hydrophobes can drastically suppress thermodynamic fluctuations, making the detection of the LLPT more difficult

Microscopic mechanism of protein cryopreservation in an aqueous solution with trehalose

In order to investigate the cryoprotective mechanism of trehalose on proteins, we use molecular dynamics computer simulations to study the microscopic dynamics of water upon cooling in an aqueous solution of lysozyme and trehalose. We find that the presence of trehalose causes global retardation of the dynamics of water. Comparing aqueous solutions of lysozyme with/without trehalose, we observe that the dynamics of water in the hydration layers close to the protein is dramatically slower when trehalose is present in the system. We also analyze the structure of water and trehalose around the lysozyme and find that the trehalose molecules form a cage surrounding the protein that contains very slow water molecules. We conclude that the transient cage of trehalose molecules that entraps and slows the water molecules prevents the crystallisation of protein hydration water upon cooling.DC, EGS, and HES thank the NSF chemistry Division for support (Grants CHE-1213217, CHE-0911389, and CHE-0908218). PG gratefully acknowledges the computational support reveived by the INFN RM3-GRID at Roma Tre University. (CHE-1213217 - NSF chemistry Division; CHE-0911389 - NSF chemistry Division; CHE-0908218 - NSF chemistry Division)Published versio

Intercultural Experiential Continuum: A Case Study of Early Childhood Teachers Working with Refugee Children

To address the cultural mismatch between early childhood teachers and refugee students in urban public school settings, this qualitative case study explores how teachers working with young refugees develop interculturally. Grounded in Dewey’s experiential transaction theory, we analyze two teachers’ contrasting trajectories of intercultural sensitivity development. Our findings highlight the agency of teachers (pre-experience worldview and motivation) and key qualities of intercultural experiences (cultural immersion, cultural isolation, authentic cultural dialog) within experiential transactions. Finally, the study bring to light teachers’ intercultural experiential continuums where relevant previous, present, and future experiences are interconnected

Hippocampal gene expression of deiodinases 2 and 3 and effects of 3,5-diiodo-L-thyronine T2 in mouse depression paradigms.

Central thyroid hormone signaling is important in brain function/dysfunction, including affective disorders and depression. In contrast to 3,3',5-triiodo-L-thyronine (T3), the role of 3,5-diiodo-L-thyronine (T2), which until recently was considered an inactive metabolite of T3, has not been studied in these pathologies. However, both T3 and T2 stimulate mitochondrial respiration, a factor counteracting the pathogenesis of depressive disorder, but the cellular origins in the CNS, mechanisms, and kinetics of the cellular action for these two hormones are distinct and independent of each other. Here, Illumina and RT PCR assays showed that hippocampal gene expression of deiodinases 2 and 3, enzymes involved in thyroid hormone regulation, is increased in resilience to stress-induced depressive syndrome and after antidepressant treatment in mice that might suggest elevated T2 and T3 turnover in these phenotypes. In a separate experiment, bolus administration of T2 at the doses 750 and 1,500 mcg/kg but not 250 mcg/kg in naive mice reduced immobility in a two-day tail suspension test in various settings without changing locomotion or anxiety. This demonstrates an antidepressant-like effect of T2 that could be exploited clinically. In a wider context, the current study suggests important central functions of T2, whose biological role only lately is becoming to be elucidated.publishersversionpublishe

Early Growth Response Gene-2 Is Essential for M1 and M2 Macrophage Activation and Plasticity by Modulation of the Transcription Factor CEBPβ

The process of macrophage polarization is involved in many pathologies such as anti-cancer immunity and autoimmune diseases. Polarized macrophages exhibit various levels of plasticity when M2/M(IL-4) macrophages are reprogrammed into an M1-like phenotype following treatment with IFNγ and/or LPS. At the same time, M1 macrophages are resistant to reprogramming in the presence of M2-like stimuli. The molecular mechanisms responsible for the macrophages polarization, plasticity of M2 macrophages, and lack of plasticity in M1 macrophages remain unknown. Here, we explored the role of Egr2 in the induction and maintenance of macrophage M1 and M2 polarization in the mouse in vitro and in vivo models of inflammation. Egr2 knockdown with siRNA treatment fail to upregulate either M1 or M2 markers upon stimulation, and the overexpression of Egr2 potentiated M1 or M2 marker expression following polarization. Polarisation with M2-like stimuli (IL-4 or IL-13) results in increased Egr2 expression, but macrophages stimulated with M1-like stimuli (IFNγ, LPS, IL-6, or TNF) exhibit a decrease in Egr2 expression. Egr2 was critical for the expression of transcription factors CEBPβ and PPARγ in M2 macrophages, and CEBPβ was highly expressed in M1-polarized macrophages. In siRNA knockdown studies the transcription factor CEBPβ was found to negatively regulate Egr2 expression and is likely to be responsible for the maintenance of the M1-like phenotype and lack plasticity. During thioglycolate-induced peritonitis, adoptively transferred macrophages with Egr2 knockdown failed to become activated as determined by upregulation of MHC class II and CD86. Thus, our study indicates that Egr2 expression is associated with the ability of unstimulated or M2 macrophages to respond to stimulation with inflammatory stimuli, while low levels of Egr2 expression is associated with non-responsiveness of macrophages to their activation

КАЧЕСТВО ОБРАЗОВАНИЯ КАК ФАКТОР ЕГО КОНКУРЕНТОСПОСОБНОСТИ В УСЛОВИЯХ ГЛОБАЛИЗАЦИИ ОБЩЕСТВА

Abstract. The authors see the task to improve the competitiveness of Russian higher education to be associated with the quality of educational services and their conformation to the needs of society, state, education and personality. The quality of higher education has integrated character and depends on the quality of educational processes and education system functioning, various internal and external factors. At the same time, the competitiveness of Russian education depends on its access to the world educational space, supply of foreign and Russian students with open educational courses that are in demand and development of e-learning. Informatization of education becomes a mean of increasing the competitiveness of higher education and its quality. However, the transfer of educational process to the open educational space results in potential didactic possibilities of e-learning that contribute to improving the quality of education, and the technological, methodological, communicative, health problems that reduce the quality of education. Аннотация. Задача повышения конкурентоспособности российского высшего образования связана с качеством предоставляемых образовательных услуг, соответствием результатов профессиональной подготовки потребностям общества, государства, системы образования, личности. Обладая интегральным характером, качество высшего образования зависит от качества организации образовательных процессов и функционирования системы образования, различных внутренних и внешних факторов. Одновременно конкурентоспособность российского образования зависит от его выхода в мировое образовательное пространство, предоставления зарубежным и российским обучающимся востребованных открытых образовательных курсов, развития электронных средств обучения. Информатизация образования становится средством повышения конкурентоспособности высшего образования и его качества. Однако перенос учебного процесса в открытую образовательную среду сопровождается как потенциальными дидактическими возможностями электронных средств обучения, способствующих повышению качества образования, так и технологическими, методическими, коммуникативными, валеологическими проблемами, снижающими качество образования.