•Transcranial ultrasound stimulation (TUS) has higher spatial resolution and deeper penetration compared to other non-invasive stimulation methods.•TUS can produce short-term and long-lasting changes ...in neuronal excitability and spontaneous firing rate of neurons.•TUS holds great potential as an investigative tool in neuroscience and as a treatment for neurological and psychiatric disorders.
Transcranial ultrasound stimulation (TUS) holds great potential as a tool to alter neural circuits non-invasively in both animals and humans. In contrast to established non-invasive brain stimulation methods, ultrasonic waves can be focused on both cortical and deep brain targets with the unprecedented spatial resolution as small as a few cubic millimeters. This focusing allows exclusive targeting of small subcortical structures, previously accessible only by invasive deep brain stimulation devices. The neuromodulatory effects of TUS are likely derived from the kinetic interaction of the ultrasound waves with neuronal membranes and their constitutive mechanosensitive ion channels, to produce short term and long-lasting changes in neuronal excitability and spontaneous firing rate. After decades of mechanistic and safety investigation, the technique has finally come of age, and an increasing number of human TUS studies are expected. Given its excellent compatibility with non-invasive brain mapping techniques, such as electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), as well as neuromodulatory techniques, such as transcranial magnetic stimulation (TMS), systemic TUS effects can readily be assessed in both basic and clinical research. In this review, we present the fundamentals of TUS for a broader audience. We provide up-to-date information on the physical and neurophysiological mechanisms of TUS, available readouts for its neural and behavioral effects, insights gained from animal models and human studies, potential clinical applications, and safety considerations. Moreover, we discuss the indirect effects of TUS on the nervous system through peripheral co-stimulation and how these confounding factors can be mitigated by proper control conditions.
A class of billiards is found, the geometry of which can change with a change in the energy of a ball moving on a ‘‘billiard table.’’ Such billiards are called force or evolutionary billiards. They ...make it possible to implement important integrable Hamiltonian systems (with two degrees of freedom) on the entire
-dimensional phase space of the system at once. That is, simultaneously on all regular isoenergetic
-dimensional surfaces. We have previously proven that force billiards implement the Euler and Lagrange integrable cases in the dynamics of a heavy body in
-dimensional space. It is found that these two well-known systems are ‘‘billiard equivalent,’’ although they have integrals of different degrees—quadratic (Euler) and linear (Lagrange).
The article reveals the main features and characteristics of the algorithm of actions to ensure environmental safety of the population in the areas of oil refineries based on the mechanism of health ...risk assessment at all stages of the life cycle of environmentally hazardous production facilities. Methodologically, the algorithm implements the provisions of existing standards, regulatory documents and recommendations on health risk assessment of the population and is a sequence of procedures for making informed decisions on ensuring that health risk to the population exposed to potential negative environmental impacts meets the regulatory level. Application of the algorithm ensures compliance with the regulatory level of environmental impacts on the border of the sanitary protection zone of oil refineries and adjacent residential areas.
A special emphasis is made on the stages of design and operation of environmentally hazardous objects, when the level of created health risks is especially sensitive to the results of decisions made. Timely identification of hazards and assessment of health risks at the design stage helps to choose the location of environmentally hazardous facilities, considering created risks in specific industrial and urban conditions. At the operation stage, the areas with highest risk levels of the sanitary protection zone boundary and the industrial site are identified, as well as priority production facilities and chemical toxicants (in terms of created risks). This gives a reason for adjusting the programs of industrial and environmental control, for specifying the priority of investment programs and plans of environmental protection measures. In practical terms the specific features of actions in conditions of high risks are defined to ensure the health risk meets the regulatory level in functioning of environmentally hazardous oil refining object, avoiding significant financial environmental costs as a result of making ecologically insufficiently justified planning and technological decisions at the design stage. The algorithm is universal, because it can be used for the existing production facilities and new construction projects, regardless of industry specifics.
The article reveals features of the ongoing transformations in the field of consulting, planning and design in the field of regional development in the face of increasing uncertainties and risks, ...primarily related to climate change and biodiversity loss. It shows that the very basis of such work is significantly changing, as the world-system becomes more complex, during the transition from the concept of an “empty” world to a “full” world. This change includes increasing emphasis on ensuring the resilience of human-dominated ecosystems, a change in decision-making, using behavioral a “responsible” human model that best meets the needs of inclusive sustainable development.
The authors define features of consulting, planning and design of regional development in the face of increasing uncertainties and risks, as a special type of thinking activity, in a situation of approaching radical uncertainty. The article shows the necessity of supplementing natural science approaches with the tools and practices of post-normal science and the narrative theory of beliefs, as well as the ideas of K. Friston, implemented within his dynamic causal model.
Such an approach is based on a systematic approach to decision-making in regional development and pays special attention to the adaptation of individuals and communities to high risks and uncertainties, primarily climatic and natural. It helps to better reflect the diversity of geographical conditions, to clarify the range of effective solutions for sustainable development of regions and increase the long-term resilience of business.
Orbital invariants of integrable billiards on two-dimensional book tables are studied at constant energy values. These invariants are calculated from rotation functions defined on one-parameter ...families of Liouville 2-tori. For two-dimensional billiard books, a complete analogue of Liouville’s theorem is proved, action–angle variables are introduced, and rotation functions are defined. A general formula for the rotation functions of such systems is obtained. For a number of examples, the monotonicity of these functions is studied, and edge orbital invariants (rotation vectors) are calculated. It turned out that not all billiards have monotonic rotation functions, as was originally assumed by A. Fomenko’s hypothesis. However, for some series of billiards, this hypothesis is true.
The paper presents a class of billiards with varying geometry, the so-called force or evolutionary billiards, which enable us to realize, in the sense of Liouville equivalence, the well-known cases ...of Zhukovsky and Kovalevskaya for certain energy zones. On the corresponding 4-dimensional open phase submanifolds, the indicated systems are implemented for an increase in energy on all successively occurring isoenergy 3-surfaces.
In the theory of integrable Hamiltonian systems, an important role is played by the study of Liouville foliations and bifurcations of their leaves. In the compact case, the problem is solved, but the ...noncompact case remains mostly unknown. The main goal of this article is to formulate the noncompact problem and to present a set of examples of Hamiltonian systems, giving rise to noncompact bifurcations and Liouville leaves.
The bioresorption and bioactivity of hybrid composite materials containing calcium phosphates up to 60 wt.% and polylactide (PLA) were studied
in situ
and
in vitro
. The resorption dynamics of ...composites in the PBS model environment was determined. It was found that at calcium phosphate content equal to 40% or more apatite-type calcium phosphates are produced on the surface of composites during incubation in SBF. Composites in the studied range of compositions have a weak cytotoxic effect on the cell culture of Neuro-2a mouse neuroblastoma. The data obtained suggest dynamic resorption and bioactivity of composites
in vivo
.
In the paper, eight classes of integrable billiards are studied; in particular, classes introduced by the authors: elementary, topological, billiard books, billiards on the Minkowski plane, geodesic ...billiards on quadrics in three-dimensional Euclidean space, billiards in a magnetic field, and also a class containing all of the ones above. It turns out that, in the class of billiard books, topological obstacles to implementation occurred, for example, for the “twisted” Lagrange top (as we conventionally call a modification of the usual Lagrange top which we had discovered) for one of energy zones. We indicate this obstacle explicitly. It turns out further that this system can still be implemented in the class of magnetic billiards.
A class of force evolutionary billiards is discovered that realizes important integrable Hamiltonian systems on all regular isoenergy 3-surfaces simultaneously, i.e., on the phase 4-space. It is ...proved that the well-known Euler and Lagrange integrable systems are billiard equivalent, although the degrees of their integrals are different (two and one).
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