Senescent Microglia: The Key to the Ageing Brain?

Ageing represents the single biggest risk factor for development of neurodegenerative disease. Despite being such long-lived cells, microglia have been relatively understudied for their role in the ageing process. Reliably identifying aged microglia has proven challenging, not least due to the diversity of cell populations, and the limitations of available models, further complicated by differences between human and rodent cells. Consequently, the literature contains multiple descriptions and categorisations of microglia with neurotoxic phenotypes, including senescence, without any unifying markers. The role of microglia in brain homeostasis, particularly iron storage and metabolism, may provide a key to reliable identification.

Manifestation of the Factor of Regional Median Position

The article summarises theoretical approaches to determining the median regions, their place and rolein the territorial structure of the country and its socio-economic development. The basis of the approach proposedis multiple descriptions of a set of attributes, connections, and relationships, a holistic view of the region as arelatively stable part of the socio-economic space. To conduct an empirical study in Russia, 32 regions wereselected, attributed to the category of the median regions by their geographical position. According to theapproach, the list of verifiable median characteristics of the regions includes transit, polystructurality, scale,resource availability, gravity, population concentration, the role in ensuring national security, budget donation,the “pilot” character, the concentration of intellectual potential, low risks, high investment and innovationpotential, high contact with neighbouring territories, and clustering. The results of the study suggest that thecumulative effect of the regional median position has a significant differentiation. Therefore, the authors candistinguish such types of median regions as integrators of the economic space, sustainable median regions, anddeveloping median regions. Based on the topological attributes of median regions, the mission of median regionsis justified. It is substantiated that the factor of the medianness of the region can be of key importance in regionalpolicy only if this resource is used correctly in program activities, regional development strategies and regionalpolicy of the state.

Zero-Delay Multiple Descriptions of Stationary Scalar Gauss-Markov Sources

In this paper, we introduce the zero-delay multiple-description problem, where an encoder constructs two descriptions and the decoders receive a subset of these descriptions. The encoder and decoders are causal and operate under the restriction of zero delay, which implies that at each time instance, the encoder must generate codewords that can be decoded by the decoders using only the current and past codewords. For the case of discrete-time stationary scalar Gauss—Markov sources and quadratic distortion constraints, we present information-theoretic lower bounds on the average sum-rate in terms of the directed and mutual information rate between the source and the decoder reproductions. Furthermore, we show that the optimum test channel is in this case Gaussian, and it can be realized by a feedback coding scheme that utilizes prediction and correlated Gaussian noises. Operational achievable results are considered in the high-rate scenario using a simple differential pulse code modulation scheme with staggered quantizers. Using this scheme, we achieve operational rates within 0.415 bits / sample / description of the theoretical lower bounds for varying description rates.

Ionic Liquids – Further Progress on the Fundamental Issues

Ionic liquids continue to challenge conventional descriptions of liquids and their behaviour. Indeed, the ever-increasing variety of ionic liquid compounds has generated a need for multiple descriptions of the different molecular families, including protic, aprotic, solvate, and metal coordination complex families of ionic liquids, that exhibit very different behaviours. Within families, the balance of long-range electrostatic and short-range dispersion forces plays out in nanoscale heterogeneity that also impacts markedly on properties. In this perspective, we highlight some of the issues in the field that continue to deserve further investigation and development at both the experimental and fundamental levels. We also propose a set of nomenclature abbreviations in an attempt to systematise the plethora of confusing abbreviations that appear in the field. The distinction between ionic liquids, ionic liquid–solvent mixtures, and deep eutectic solvents is also discussed.

Towards the appropriate synthesis of the four-bar linkage

Uncertainties are an inherent element in all mechanisms, arising from the manufacturing and assembly process or even from the operation of the device. In terms of synthesis routines for mechanisms, uncertainties are generally neglected since they are difficult to account for. In this work, the concept of appropriate design is utilized to develop routines that can more easily account for uncertainties in the geometrical parameters. These routines have been developed for linkages, specifically the four-bar linkage, and are capable of synthesizing the complete set of design solutions, referred to as allowable regions, for a set of desired coupler curve characteristics. The description of the desired coupler curve may contain any number of precision points and (or) trajectories. Several problems are solved in this work, including obtaining a representation of the coupler curve corresponding to a set of design parameters containing uncertainties, and synthesizing the appropriate designs for multiple descriptions of desired coupler curves. The results are quite promising and show great potential for using the appropriate design methodology for linkage synthesis.