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Optics express 31(2), 3315 - 3324 (2023). doi:10.1364/OE.477774, The ability of pulsed nature of synchrotron radiation opens up the possibility of studying microsecond dynamics in complex materials via speckle-based techniques. Here, we present the study of measuring the dynamics of a colloidal system by combining single and multiple X-ray pulses of a storage ring. In addition, we apply speckle correlation techniques at various pulse patterns to collect correlation functions from nanoseconds to milliseconds. The obtained sample dynamics from all correlation techniques at different pulse patterns are in very good agreement with the expected dynamics of Brownian motions of silica nanoparticles in water. Our study will pave the way for future pulsed X-ray investigations at various synchrotron X-ray sources using individual X-ray pulse patterns., Published by Optica, Washington, DC

The journal of physical chemistry letters 14(20), 4719 - 4725 (2023). doi:10.1021/acs.jpclett.3c00631, The dynamics and time scales of higher-order correlations are studied in supercooled colloidal systems. A combination of X-ray photon correlation spectroscopy (XPCS) and X-ray cross-correlation analysis (XCCA) shows the typical slowing of the dynamics of a hard sphere system when approaching the glass transition. The time scales of higher-order correlations are probed using a novel time correlation function g$_C$, tracking the time evolution of cross-correlation function C. With an increasing volume fraction, the ratio of relaxation times of g$_C$ to the standard individual particle relaxation time obtained by XPCS increases from ∼0.4 to ∼0.9. While a value of ∼0.5 is expected for free diffusion, the increasing values suggest that the local orders within the sample are becoming more long-lived for larger volume fractions. Furthermore, the dynamics of local order is more heterogeneous than the individual particle dynamics. These results indicate that not only the presence but also the lifetime of locally favored structures increases close to the glass transition., Published by ACS, Washington, DC

Supplemental Document

Optics letters 47(2), 293 - 296 (2022). doi:10.1364/OL.444190, Three-dimensional photon correlation spectroscopy (3D PCS) is a well-known technique developed to suppress multiple scattering contributions in correlation functions, which are inevitably involved when an optical laser is employed to investigate dynamics in a turbid system. Here, we demonstrate a proof-of-principle study of 3D PCS in the hard X-ray regime. We employ an X-ray optical cross-correlator to measure the dynamics of silica colloidal nanoparticles dispersed in polypropylene glycol. The obtained cross correlation functions show very good agreement with auto-correlation measurements. This demonstration provides the foundation for X-ray speckle-based studies of very densely packed soft matter systems., Published by Soc., Washington, DC

Over the past decades, the human life span has dramatically increased, and therefore, a steady increase in diseases associated with age (such as Alzheimer's disease and Parkinson's disease) is expected. In these neurodegenerative diseases, there is a cognitive decline and memory loss, which accompany increased systemic inflammation, the inflamm-aging, and the insulin resistance. Despite numerous studies of age-related pathologies, data on the contribution of brain insulin resistance and innate immunity components to aging are insufficient. Recently, much research has been focused on the consequences of nutrients and adiposity- and nutrient-related signals in brain aging and cognitive decline. Moreover, given the role of metainflammation in neurodegeneration, lifestyle interventions such as calorie restriction may be an effective way to break the vicious cycle of metainflammation and have a role in social behavior. The various effects of calorie restriction on metainflammation, insulin resistance, and neurodegeneration have been described. Less attention has been paid to the social determinants of aging and the possible mechanism by which calorie restriction might influence social behavior. The purpose of this review is to discuss current knowledge in the interdisciplinary field of geroscience-immunosenescence, inflamm-aging, and metainflammation-which makes a significant contribution to aging. A substantial part of the review is devoted to frontiers in the brain insulin resistance in relation to neuroinflammation. In addition, we summarize new data on potential mechanisms of calorie restriction that influence as a lifestyle intervention on the social brain. This knowledge can be used to initiate successful aging and slow the onset of neurodegenerative diseases.

в статье представлены результаты практического применения методов и приемов развития образной памяти, которые положительно влияют на формирование у учащихся знаково-символических универсальных учебных действий, а также творческих способностей обучающихся.

Im ersten Teil dieser Arbeit wurde die Kinetik einer neuen kolloidchemischen Synthese von monodispersen sphärischen CdSe- und CdS-Nanopartikeln (QDs) untersucht, deren Wachstum in Gegenwart von in situ gebildetem Cd erfolgt. Reaktionen mit verschiedenen Se- und S-Ausgangsverbindungen, Cd- zu Se- und S-Verhältnissen und Mengen des Stabilisators (Ölsäure) wurden mit UV-Vis-Absorptionsspektroskopie charakterisiert. Mit Transmissionselektronenmikroskopie (TEM) wurde die Größenverteilung der CdSe- und CdS-Nanopartikel untersucht. Im zweiten Teil der Arbeit wurde die Modifikation der ursprünglich Ölsäure-beschichteten CdSe QDs mit Pyridinmolekülen durchgeführt. Die mit Pyridinliganden stabilisierten CdSe-Nanopartikel wurden mit verschiedenen Analyse-Methoden charakterisiert. Anschließend wurden die mit Pyridin behandelten CdSe QDs für die Herstellung der P3HT/CdSe-Hybridsolarzellen verwendet. Zusätzlich wurde eine Quervernetzung der Pyridin-beschichteten Nanoteilchen durchgeführt, um den Ladungstransfer zwischen Nanopartikeln zu verbessern.