Cryo-STEM-EDX spectroscopy for the characterisation of nanoparticles in cell culture media

We present a study of barium titanate nanoparticles dispersed in cell culture media. Scanning transmission electron microscopy combined with energy dispersive X-ray spectroscopy was undertaken on samples prepared using both conventional drop casting and also plunge freezing and examination under cryogenic conditions. This showed that drying artefacts occurred during conventional sample preparation, whereby some salt components of the cell culture media accumulated around the barium titanate nanoparticles; these were removed using the cryogenic route. Importantly, the formation of a calcium and phosphorus rich coating around the barium titanate nanoparticles was retained under cryo-conditions, highlighting that significant interactions do occur between nanomaterials and biological media

Cycles of construing in radicalization and deradicalization: a study of Salafist Muslims.

© Taylor & Francis Group, LLC.This article explores radicalization and deradicalization by considering the experiences of six young Tunisian people who had become Salafist Muslims. Their responses to narrative interviews and repertory grid technique are considered from a personal construct perspective, revealing processes of construing and reconstruing, as well as relevant aspects of the structure and content of their construct systems. In two cases, their journeys involved not only radicalization but self-deradicalization, and their experiences are drawn on to consider implications for deradicalization.Peer reviewedFinal Accepted Versio

Hybrid in vitro diffusion cell for simultaneous evaluation of hair and skin decontamination: temporal distribution of chemical contaminants

Most casualty or personnel decontamination studies have focused on removing contaminants from the skin. However, scalp hair and underlying skin are the most likely areas of contamination following airborne exposure to chemicals. The aim of this study was to investigate the interactions of contaminants with scalp hair and underlying skin using a hybrid in vitro diffusion cell model. The in vitro hybrid test system comprised “curtains” of human hair mounted onto sections of excised porcine skin within a modified diffusion cell. The results demonstrated that hair substantially reduced underlying scalp skin contamination and that hair may provide a limited decontamination effect by removing contaminants from the skin surface. This hybrid test system may have application in the development of improved chemical incident response processes through the evaluation of various hair and skin decontamination strategies.Peer reviewedFinal Published versio

Dynamics of surfactant-laden evaporating droplets

We consider the flow dynamics of a thin evaporating droplet in\ud the presence of an insoluble surfactant and small particles in the bulk. Evolution\ud equations for the film height, the interfacial surfactant and bulk particle concentra-\ud tion are derived using a lubrication model coupled by a constitutive relation for the\ud dependence of the viscosity on local particle concentration. An important ingredient\ud of our model is that it takes into account the fact that the surfactant adsorbed at\ud the surface hinders the evaporation. Time-dependent simulations are performed to\ud determine how the presence of surfactants affects the evaporation and flow dynamics\ud with and without the presence of particles in the bulk. We discuss the various mech-\ud anisms that affect the shape of the droplet as it evaporates as well as the resulting\ud pattern of particle deposition

IFNAR1-Signalling Obstructs ICOS-mediated Humoral Immunity during Non-lethal Blood-Stage Plasmodium Infection

Funding: This work was funded by a Career Development Fellowship (1028634) and a project grant (GRNT1028641) awarded to AHa by the Australian National Health & Medical Research Council (NHMRC). IS was supported by The University of Queensland Centennial and IPRS Scholarships. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

Necessary Skills and Knowledge for Staff Providing Telehealth Services

Background Although motor abnormalities have been flagged as potentially the most sensitive and specific clinical features for predicting the future progression to Parkinson's disease, little work has been done to characterize gait and balance impairments in idiopathic rapid eye movement sleep behavior disorder (iRBD). Objective The objective of this study was to quantitatively determine any static balance as well as gait impairments across the 5 independent domains of gait in polysomnography-confirmed iRBD patients using normal, fast-paced, and dual-task walking conditions. Methods A total of 38 participants (24 iRBD, 14 healthy controls) completed the following 5 different walking trials across a pressure sensor carpet: (1) normal pace, (2) fast pace, (3) while counting backward from 100 by 1s, (4) while naming as many animals as possible, (5) while subtracting 7s from 100. Results Although no gait differences were found between the groups during normal walking, there were significant differences between groups under the fast-paced and dual-task gait conditions. Specifically, in response to the dual tasking, healthy controls widened their step width without changing step width variability, whereas iRBD patients did not widen their step width but, rather, significantly increased their step width variability. Similarly, changes between the groups were observed during fast-paced walking wherein the iRBD patients demonstrated greater step length asymmetry when compared with controls. Conclusions This study demonstrates that iRBD patients have subtle gait impairments, which likely reflect early progressive degeneration in brainstem regions that regulate both REM sleep and gait coordination. Such gait assessments may be useful as a diagnostic preclinical screening tool for future fulminant gait abnormalities for trials of disease-preventive agents. (c) 2019 International Parkinson and Movement Disorder Societ

Superspreading: Mechanisms and Molecular Design

The intriguing ability of certain surfactant molecules to drive the superspreading of liquids to complete wetting on hydrophobic substrates is central to numerous applications that range from coating flow technology to enhanced oil recovery. Despite significant experimental efforts, the precise mechanisms underlying superspreading remain unknown to date. Here, we isolate these mechanisms by analyzing coarse-grained molecular dynamics simulations of surfactant molecules of varying molecular architecture and substrate affinity. We observe that for superspreading to occur, two key conditions must be simultaneously satisfied: the adsorption of surfactants from the liquid–vapor surface onto the three-phase contact line augmented by local bilayer formation. Crucially, this must be coordinated with the rapid replenishment of liquid–vapor and solid–liquid interfaces with surfactants from the interior of the droplet. This article also highlights and explores the differences between superspreading and conventional surfactants, paving the way for the design of molecular architectures tailored specifically for applications that rely on the control of wetting

A combined XAS and XRD Study of the High-Pressure Behaviour of GaAsO4 Berlinite

Combined X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) experiments have been carried out on GaAsO4 (berlinite structure) at high pressure and room temperature. XAS measurements indicate four-fold to six-fold coordination changes for both cations. The two local coordination transformations occur at different rates but appear to be coupled. A reversible transition to a high pressure crystalline form occurs around 8 GPa. At a pressure of about 12 GPa, the system mainly consists of octahedral gallium atoms and a mixture of arsenic in four-fold and six-fold coordinations. A second transition to a highly disordered material with both cations in six-fold coordination occurs at higher pressures and is irreversible.Comment: 8 pages, 5 figures, LaTeX2

Скринінг гіпоглікемічної активності екстрактів з листя Мучниці звичайної та вивчення гострої токсичності

Diabetes mellitus type 2 (DM2) is a global health problem. The plant origin medicinal preparations revealed different mechanisms of antidiabetic action. Despite a wide range of plants that have already been studied, other species are of interest. Particularly, Bearberry (Arctostaphylos uva-ursi) attracted our attention because its leaves are rich with biologically active compounds, but hypoglycemic activity has not been studied yet.The aim of our experiment was studding acute toxicity and hypoglycemic activity of Bearberry extracts on non-diabetic standard models.Materials and methods. It was conducted the screening of hypoglycemic effect in healthy rats, oral glucose tolerance test in healthy rats and study of acute toxicity. The object of study were water and alcohol polyphenol extracts of Bearberry leaves (extractor –alcohol 50 % and 90 %). Results and discussion. Screening and comparative study shows that the maximal hypoglycemic activity revealed Bearberry leaves alcohol extract (extractor – 50 % ethanol, PE50) in dose 100 mg/kg. The least pronounced effect was observed for the introduction of water extract administration.Conclusions. The results indicate the practicability of this Bearberry leaves extract further study for renewal the range of medicinal products that revealed hypoglycemic activity.Сахарный диабет 2 типа (СД2) является глобальной проблемой здравоохранения. Эффективность лекарственных препаратов растительного происхождения объясняется различными механизмами антидиабетического действия. Несмотря на широкий спектр изученных растений, интерес представляют и другие виды. В частности, Толокнянка обыкновенная (Arctostaphylos uva-ursi) представляет научный интерес, так как ее листья богаты биологически активными соединениями, однако их гипогликемическая активность еще не изучена.Целью нашего эксперимента было изучение острой токсичности и гипогликемической активности экстрактов Толокнянки обыкновенной на недиабетических стандартных моделях.Материалы и методы. Было проведено исследование гипогликемической активности на здоровых крысах, пероральный тест толерантности к глюкозе на здоровых крысах и исследование острой токсичности. Объектом исследования были водный и спиртовые полифенольные экстракты листьев Толокнянки обыкновенной (экстрагент – алкоголь 50 % и 90 %).Результаты и их обсуждение. Скрининг и сравнительное исследование показывают, что максимальную гипогликемическую активность проявил спиртовый экстракт из листьев Толокнянки обыкновенной (экстрагент – 50 % этанола, PE50) в дозе 100 мг/кг. Наименьший гипогликемический эффект наблюдался при введении водного экстракта.Выводы. Результаты показали целесообразность дальнейшего изучения экстракта листьев Толокнянки обыкновенной для пополнения ассортимента лекарственных препаратов с гипогликемической активностью.Цукровий діабет 2 типу (ЦД2) є глобальною проблемою охорони здоров’я. Ефективність лікарських препаратів рослинного походження пояснюється різними механізмами антидіабетичної дії. Незважаючи на широкий спектр рослин, які вже піддавалися вивченню, інтерес представляють і інші види. Зокрема, Мучниця звичайна (Arctostaphylos uva-ursi) привернула нашу увагу, так як її листя багате на біологічно активні сполуки, однак їх гіпоглікемічна активність ще не вивчена.Мета даного експерименту полягала у вивченні гострої токсичності та гіпоглікемічної активності екстрактів Мучниці звичайної на стандартних моделях у здорових щурів.Матеріали та методи. Було проведено дослідження гіпоглікемічної активності на здорових щурах, пероральний тест толерантності до глюкози на здорових щурах і дослідження гострої токсичності. Об’єктом дослідження були водний і спиртові поліфенольні екстракти листя мучниці звичайної (екстрагент – етанол 50 % і 90 %).Результати та їх обговорення. Скринінг і порівняльне дослідження показують, що максимальну гіпоглікемічну активність проявив спиртовий екстракт з листя Мучниці звичайної (екстрагент – 50 % етанолу, PE50) в дозі 100 мг/кг. Найменший гіпоглікемічний ефект спостерігався при введенні водного екстракту.Висновки. Результати показали доцільність подальшого вивчення екстракту листя Мучниці звичайної для оновлення асортименту лікарських препаратів з гіпоглікемічною активністю