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Brain Stimulation 2016This review updates and consolidates evidence on the safety of transcranial Direct Current Stimulation (tDCS). Safety is here operationally defined by, and limited to,... (Review)
Review
This review updates and consolidates evidence on the safety of transcranial Direct Current Stimulation (tDCS). Safety is here operationally defined by, and limited to, the absence of evidence for a Serious Adverse Effect, the criteria for which are rigorously defined. This review adopts an evidence-based approach, based on an aggregation of experience from human trials, taking care not to confuse speculation on potential hazards or lack of data to refute such speculation with evidence for risk. Safety data from animal tests for tissue damage are reviewed with systematic consideration of translation to humans. Arbitrary safety considerations are avoided. Computational models are used to relate dose to brain exposure in humans and animals. We review relevant dose-response curves and dose metrics (e.g. current, duration, current density, charge, charge density) for meaningful safety standards. Special consideration is given to theoretically vulnerable populations including children and the elderly, subjects with mood disorders, epilepsy, stroke, implants, and home users. Evidence from relevant animal models indicates that brain injury by Direct Current Stimulation (DCS) occurs at predicted brain current densities (6.3-13 A/m(2)) that are over an order of magnitude above those produced by conventional tDCS. To date, the use of conventional tDCS protocols in human trials (≤40 min, ≤4 milliamperes, ≤7.2 Coulombs) has not produced any reports of a Serious Adverse Effect or irreversible injury across over 33,200 sessions and 1000 subjects with repeated sessions. This includes a wide variety of subjects, including persons from potentially vulnerable populations.
Topics: Animals; Brain; Computer Simulation; Epilepsy; Evidence-Based Practice; Humans; Models, Animal; Stroke; Transcranial Direct Current Stimulation
PubMed: 27372845
DOI: 10.1016/j.brs.2016.06.004 -
Biomolecules May 2022We report on the fabrication of single-electron devices based on horse-spleen ferritin particles. At low temperatures the current vs. voltage characteristics are stable,...
We report on the fabrication of single-electron devices based on horse-spleen ferritin particles. At low temperatures the current vs. voltage characteristics are stable, enabling the acquisition of reproducible data that establishes the Coulomb blockade as the main transport mechanism through them. Excellent agreement between the experimental data and the Coulomb blockade theory is demonstrated. Single-electron charge transport in ferritin, thus, establishes a route for further characterization of their, e.g., magnetic, properties down to the single-particle level, with prospects for electronic and medical applications.
Topics: Animals; Electrons; Ferritins; Horses; Spleen
PubMed: 35625632
DOI: 10.3390/biom12050705 -
The Journal of Physical Chemistry... Jun 2022The Coulomb explosion of tribromomethane (bromoform, CHBr) induced by 28 fs near-infrared laser pulses is investigated by three-dimensional coincidence ion momentum...
The Coulomb explosion of tribromomethane (bromoform, CHBr) induced by 28 fs near-infrared laser pulses is investigated by three-dimensional coincidence ion momentum imaging. We focus on the fragmentation into three, four, and five ionic fragments measured in coincidence and present different ways of visualizing the three-dimensional momentum correlations. We show that the experimentally observed momentum correlations for 4- and 5-fold coincidences are well reproduced by classical Coulomb explosion simulations and contain information about the structure of the parent molecule that could be used to differentiate structural isomers formed, for example, in a pump-probe experiment. Our results thus provide a clear path toward visualizing structural dynamics in polyatomic molecules by strong-field-induced Coulomb explosion imaging.
Topics: Ions; Lasers; Trihalomethanes
PubMed: 35727076
DOI: 10.1021/acs.jpclett.2c01007 -
Advanced Science (Weinheim,... Jun 2021Next-generation Li-ion batteries (LIBs) with higher energy density adopt some novel anode materials, which generally have the potential to exhibit higher capacity,... (Review)
Review
Next-generation Li-ion batteries (LIBs) with higher energy density adopt some novel anode materials, which generally have the potential to exhibit higher capacity, superior rate performance as well as better cycling durability than conventional graphite anode, while on the other hand always suffer from larger active lithium loss (ALL) in the first several cycles. During the last two decades, various pre-lithiation strategies are developed to mitigate the initial ALL by presetting the extra Li sources to effectively improve the first Coulombic efficiency and thus achieve higher energy density as well as better cyclability. In this progress report, the origin of the huge initial ALL of the anode and its effect on the performance of full cells are first illustrated in theory. Then, various pre-lithiation strategies to resolve these issues are summarized, classified, and compared in detail. Moreover, the research progress of pre-lithiation strategies for the representative electrochemical systems are carefully reviewed. Finally, the current challenges and future perspectives are particularly analyzed and outlooked. This progress report aims to bring up new insights to reassess the significance of pre-lithiation strategies and offer a guideline for the research directions tailored for different applications based on the proposed pre-lithiation strategies summaries and comparisons.
PubMed: 34165896
DOI: 10.1002/advs.202005031 -
Scientific Reports Jan 2021The Coulomb interaction between a photoelectron and its parent ion plays an important role in a large range of light-matter interactions. In this paper we obtain a...
The Coulomb interaction between a photoelectron and its parent ion plays an important role in a large range of light-matter interactions. In this paper we obtain a direct insight into the Coulomb interaction and resolve, for the first time, the phase accumulated by the laser-driven electron as it interacts with the Coulomb potential. Applying extreme-ultraviolet interferometry enables us to resolve this phase with attosecond precision over a large energy range. Our findings identify a strong laser-Coulomb coupling, going beyond the standard recollision picture within the strong-field framework. Transformation of the results to the time domain reveals Coulomb-induced delays of the electrons along their trajectories, which vary by tens of attoseconds with the laser field intensity.
PubMed: 33436698
DOI: 10.1038/s41598-020-79805-x -
ACS Applied Materials & Interfaces Aug 2022Nanotopography is an effective method to regulate cells' behaviors to improve Ti orthopaedic implants' in vivo performance. However, the mechanism underlying cellular...
Nanotopography is an effective method to regulate cells' behaviors to improve Ti orthopaedic implants' in vivo performance. However, the mechanism underlying cellular matrix-nanotopography interactions that allows the modulation of cell adhesion has remained elusive. In this study, we have developed novel nanotopographic features on Ti substrates and studied human osteoblast (HOb) adhesion on nanotopographies to reveal the interactive mechanism regulating cell adhesion and spreading. Through nanoflat, nanoconvex, and nanoconcave TiO nanotopographies, the evolution of Coulomb's force between the extracellular matrix and nanotopographies has been estimated and comparatively analyzed, along with the assessment of cellular responses of HOb. We show that HObs exhibited greater adhesion and spreading on nanoconvex surfaces where they formed super matured focal adhesions and an ordered actin cytoskeleton. It also demonstrated that Coulomb's force on nanoconvex features exhibits a more intense and concentrated evolution than that of nanoconcave features, which may result in a high dense distribution of fibronectin. Thus, this work is meaningful for novel Ti-based orthopaedic implants' surface designs for enhancing their in vivo performance.
Topics: Cell Adhesion; Focal Adhesions; Humans; Osteoblasts; Surface Properties; Titanium
PubMed: 35867934
DOI: 10.1021/acsami.2c07652 -
Proceedings. Mathematical, Physical,... Jul 2020This review presents the current status of experimental evidence for the occurrence of reflection-asymmetric or 'pear' shapes in atomic nuclei, which arises from the...
This review presents the current status of experimental evidence for the occurrence of reflection-asymmetric or 'pear' shapes in atomic nuclei, which arises from the presence of strong octupole correlations in the nucleon-nucleon interactions. The behaviour of energy levels and electric octupole transition moments is reviewed, with particular emphasis on recent measurements. The relevance of nuclear pear shapes to measurements of fundamental interactions is also discussed.
PubMed: 32821242
DOI: 10.1098/rspa.2020.0202 -
The Kaohsiung Journal of Medical... Feb 2012Physical aspects of medical science involve making physical models, physical approaches, and measurements by physical instruments. Among these, the physical approach is... (Review)
Review
Physical aspects of medical science involve making physical models, physical approaches, and measurements by physical instruments. Among these, the physical approach is the most important for an exact elucidation of the physiological function of living materials. What is a physical approach? In the first step, the molecular mechanism of visual transduction will be demonstrated by considering the physical characteristics of diffusion of second messengers. In the next step, I will consider how frequency modulation-type impulse signaling is converted from amplitude modulation-type electric signaling. In the last section, I will discuss how impulse signaling (i.e., the train of action potentials) is processed by the neural network in the brain and eventually is recognized in the frontal cortex using near infrared spectroscopy. In order to obtain such a physical model of vision, many physical concepts are used, such as light reflex, energy transduction, diffusion of molecules, threshold, the Coulomb interaction, light absorption, and cluster analysis. Among them, the Coulomb interaction, light absorption, and diffusion of molecules are three essential keywords for the physical process.
Topics: Action Potentials; Biophysics; Eye; Functional Neuroimaging; Humans; Light Signal Transduction; Models, Biological; Ocular Physiological Phenomena; Optical Phenomena
PubMed: 22301010
DOI: 10.1016/j.kjms.2011.08.005 -
Annual Review of Physical Chemistry Apr 2023We review our recent quantum stochastic model for spectroscopic lineshapes in the presence of a coevolving and nonstationary background population of excitations.... (Review)
Review
We review our recent quantum stochastic model for spectroscopic lineshapes in the presence of a coevolving and nonstationary background population of excitations. Starting from a field theory description for interacting bosonic excitons, we derive a reduced model whereby optical excitons are coupled to an incoherent background via scattering as mediated by their screened Coulomb coupling. The Heisenberg equations of motion for the optical excitons are then driven by an auxiliary stochastic population variable, which we take to be the solution of an Ornstein-Uhlenbeck process. Here, we present an overview of the theoretical techniques we have developed as applied to predicting coherent nonlinear spectroscopic signals. We show how direct (Coulomb) and exchange coupling to the bath give rise to distinct spectral signatures and discuss mathematical limits on inverting spectral signatures to extract the background density of states.
PubMed: 36854178
DOI: 10.1146/annurev-physchem-102822-100922 -
Polymers Mar 2023Electronic devices commonly use rechargeable Li-ion batteries due to their potency, manufacturing effectiveness, and affordability. Electrospinning technology offers... (Review)
Review
Electronic devices commonly use rechargeable Li-ion batteries due to their potency, manufacturing effectiveness, and affordability. Electrospinning technology offers nanofibers with improved mechanical strength, quick ion transport, and ease of production, which makes it an attractive alternative to traditional methods. This review covers recent morphology-varied nanofibers and examines emerging nanofiber manufacturing methods and materials for battery tech advancement. The electrospinning technique can be used to generate nanofibers for battery separators, the electrodes with the advent of flame-resistant core-shell nanofibers. This review also identifies potential applications for recycled waste and biomass materials to increase the sustainability of the electrospinning process. Overall, this review provides insights into current developments in electrospinning for batteries and highlights the commercialization potential of the field.
PubMed: 37050236
DOI: 10.3390/polym15071622