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Finely-tuned gamma (FTG) oscillations can be recorded from cortex or the subthalamic nucleus (STN) in patients with Parkinson's disease (PD) on dopaminergic medication, and have been associated with dyskinesias. When recorded during deep brain stimulation (DBS) on medication the FTG is entrained to half the stimulation frequency. We investigated whether these characteristics are shared off medication by recording local field potentials (LFP) from the STN from externalised DBS leads in 14 PD patients after overnight withdrawal of medication. FTG was induced de-novo by DBS in the absence of dyskinesias in a third of our cohort. The FTG could outlast stimulation or arise only after DBS ceased. FTG frequencies decreased during and across consecutive DBS blocks, but did not shift with changing stimulation frequency off medication. Together with the sustained after-effects this argues against simple entrainment by DBS in the off medication state. We also found significant coherence between STN-LFP and electroencephalogram (EEG) signals at FTG frequencies. We conclude that FTG is a network phenomenon that behaves differently in the off medication state, when it is neither associated with dyskinesias nor susceptible to entrainment.

Local field potentials (LFPs) may afford insight into the mechanisms of action of deep brain stimulation (DBS) and potential feedback signals for adaptive DBS. In Parkinson's disease (PD) DBS of the subthalamic nucleus (STN) suppresses spontaneous activity in the beta band and drives evoked resonant neural activity (ERNA). Here, we investigate how STN LFP activities change over time following the onset and offset of DBS. To this end we recorded LFPs from the STN in 14 PD patients during long (mean: 181.2 s) and short (14.2 s) blocks of continuous stimulation at 130 Hz. LFP activities were evaluated in the temporal and spectral domains. During long stimulation blocks, the frequency and amplitude of the ERNA decreased before reaching a steady state after ~70 s. Maximal ERNA amplitudes diminished over repeated stimulation blocks. Upon DBS cessation, the ERNA was revealed as an under-damped oscillation, and was more marked and lasted longer after short duration stimulation blocks. In contrast, activity in the beta band suppressed within 0.5 s of continuous DBS onset and drifted less over time. Spontaneous activity was also suppressed in the low gamma band, suggesting that the effects of high frequency stimulation on spontaneous oscillations may not be selective for pathological beta activity. High frequency oscillations were present in only six STN recordings before stimulation onset and their frequency was depressed by stimulation. The different dynamics of the ERNA and beta activity with stimulation imply different DBS mechanisms and may impact how these activities may be used in adaptive feedback.

Parkinsonian bradykinesia and rigidity are typically associated with excessive beta band oscillations in the subthalamic nucleus. Recently another spectral peak has been identified that might be implicated in the pathophysiology of the disease: high-frequency oscillations (HFO) within the 150–400Hz range. Beta-HFO phase-amplitude coupling (PAC) has been found to correlate with severity of motor impairment. However, the neuronal origin of HFO and its usefulness as a potential target for deep brain stimulation remain to be established. For example, it is unclear whether HFO arise from the same neural populations as beta oscillations. We intraoperatively recorded local field potentials from the subthalamic nucleus while advancing DBS electrodes in 2mm steps from 4mm above the surgical target point until 2mm below, resulting in 4 recording sites. Data from 26 nuclei from 14 patients were analysed. For each trajectory, we identified the recording site with the largest spectral peak in the beta range (13–30Hz), and the largest peak in the HFO range separately. In addition, we identified the recording site with the largest beta-HFO PAC. Recording sites with largest beta power and largest HFO power coincided in 50% of cases. In the other 50%, HFO was more likely to be detected at a more superior recording site in the target area. PAC followed more closely the site with largest HFO (45%) than beta power (27%). HFO are likely to arise from spatially close, but slightly more superior neural populations than beta oscillations. Further work is necessary to determine whether the different activities can help fine-tune deep brain stimulation targeting. Keywords: Electrophysiology, Oscillations, Basal ganglia, Cross-frequency coupling, Parkinson's disease, Motor system

How cortical oscillations are involved in the coordination of functionally coupled muscles and how this is modulated by different movement contexts (static vs dynamic) remains unclear. Here, this is investigated by recording high-density electroencephalography (EEG) and electromyography (EMG) from different forearm muscles while healthy participants (n = 20) performed movement tasks (static and dynamic posture holding, and reaching) with their dominant hand. When dynamic perturbation was applied, beta band (15–35 Hz) activities in the motor cortex contralateral to the performing hand reduced during the holding phase, comparative to when there was no perturbation. During static posture holding, transient periods of increased cortical beta oscillations (beta bursts) were associated with greater corticomuscular coherence and increased phase synchrony between muscles (intermuscular coherence) in the beta frequency band compared to the no-burst period. This effect was not present when resisting dynamic perturbation. The results suggest that cortical beta bursts assist synchronisation of different muscles during static posture holding in healthy motor control, contributing to the maintenance and stabilisation of functional muscle groups. Theoretically, increased cortical beta oscillations could lead to exaggerated synchronisation in different muscles making the initialisation of movements more difficult, as observed in Parkinson's disease.

Abstract When someone violates a social norm, others may think that some sanction would be appropriate. We examine how the experience of emotions like anger and disgust relate to the judged appropriateness of sanctions, in a pre-registered analysis of data from a large-scale study in 56 societies. Across the world, we find that individuals who experience anger and disgust over a norm violation are more likely to endorse confrontation, ostracism and, to a smaller extent, gossip. Moreover, we find that the experience of anger is consistently the strongest predictor of judgments of confrontation, compared to other emotions. Although the link between state-based emotions and judgments may seem universal, its strength varies across countries. Aligned with theoretical predictions, this link is stronger in societies, and among individuals, that place higher value on individual autonomy. Thus, autonomy values may increase the role that emotions play in guiding judgments of social sanctions.

Introduction: Alzheimer’s disease (AD) is a severe neurodegenerative disease characterized by loss of synaptic connection between neurons of the cortex and subcortical regions. The cholinergic deficit is a consistent and early finding in AD, hence acetylcholinesterase inhibitors (AChEIs) are used for symptomatic improvement of AD. Most of these therapeutic agents are hepatotoxic, leading to liver failure and other complications. Therefore, the study of new AChEIs with less toxic impact and better effectivity is a topical challenge. In view of this, we synthesized novel chemical compounds: TVA and TVS that possess AChEI activity and studied their neuroprotective effect in an experimental AD model. Materials and methods: Studies were performed on white rats. Acute toxicity studies were performed by Karber’s method. AD was induced via bilateral intracerebroventricular administration of Aβ 25–35. Histopathological examinations were performed in the hippocampus and the entorhinal cortex. Liver tissue was additionally examined to monitor the hepatotoxicity of these compounds. Results: Studies of the hippocampus showed that compared to control and TVA-treated groups, under the influence of TVS there were few morphological alterations. Experimental groups showed an increase in the glial cell count, compared to the intact animals. In comparison to the AD group, the increase in microglia was not that prominent under the action of the novel compounds. Under the influence of TVA and TVS, the entorhinal cortex was more susceptible to neuronal injury, although TVS protected pyramidal neurons. Also, the group treated with TVA had signs of acute liver damage, while under the influence of TVS there were no signs of liver changes. Discussion: Histopathological examination showed that the neurodegenerative processes in the hippocampus, as well as in the entorhinal cortex, were significantly reduced under the influence of TVS, compared with the control group. At the same time, TVA had no significant effect on the protection of neuronal cells. Also, TVS was less toxic, and there was no sign of hepatotoxicity during the experiments. Conclusion: These studies demonstrated that TVS possesses neuroprotective activity and reduces neuronal damage induced by Aβ. Graphical abstract:

Background: Irregular cardiac motion can render conventional segmented cine MRI nondiagnostic. Clustering has been proposed for cardiac motion binning and may be optimized for complex arrhythmias. Purpose: To develop an adaptive cluster optimization method for irregular cardiac motion, and to generate the corresponding time‐resolved cine images. Study Type: Prospective. Subjects: Thirteen with atrial fibrillation, four with premature ventricular contractions, and one patient in sinus rhythm. Field Strength/Sequence: Free‐running balanced steady state free precession (bSSFP) with sorted golden‐step, reference real‐time sequence. Assessment: Each subject underwent both the sorted golden‐step bSSFP and the reference Cartesian real‐time imaging. Golden‐step bSSFP images were reconstructed using the dynamic regularized adaptive cluster optimization (DRACO) method and k‐means clustering. Image quality (4‐point Likert scale), signal‐to‐noise ratio (SNR), contrast‐to‐noise ratio (CNR), edge sharpness, and ventricular function were assessed. Statistical Tests: Paired t‐tests, Friedman test, regression analysis, Fleiss' Kappa, Bland–Altman analysis. Significance level P < 0.05. Results: The DRACO method had the highest percent of images with scores ≥3 (96% for diastolic frame, 93% for systolic frame, and 93% for multiphase cine) and the percentages were significantly higher compared with both the k‐means and real‐time methods. Image quality scores, SNR, and CNR were significantly different between DRACO vs. k‐means and between DRACO vs. real‐time. Cardiac function analysis showed no significant differences between DRACO vs. the reference real‐time. Conclusion: DRACO with time‐resolved reconstruction generated high quality images and has early promise for quantitative cine cardiac MRI in patients with complex arrhythmias including atrial fibrillation. Level of Evidence: 1. Technical Efficacy: Stage 2. [ABSTRACT FROM AUTHOR]

The gradient technique is a promising tool with theoretical foundations based on the fundamental properties of MHD turbulence and turbulent reconnection. Its various incarnations use spectroscopic, synchrotron, and intensity data to trace the magnetic field and measure the media magnetization in terms of Alfvén Mach number. We provide an analytical theory of gradient measurements and quantify the effects of averaging gradients along the line of sight and over the plane of the sky. We derive analytical expressions that relate the properties of gradient distribution with the Alfvén Mach number M _A . We show that these measurements can be combined with measures of sonic Mach number or line broadening to obtain the magnetic field strength. The corresponding technique has advantages to the Davis–Chandrasekhar–Fermi way of obtaining the magnetic field strength.

A personal view of the Mexican mathematical physicist Kurt Bernardo Wolf (1942-2022) is presented here.

Background: Imaging techniques of analysis in undisturbed soil samples are powerful tools for understanding soil properties and functioning. Although micromorphological analysis has always been applied for studying soil genesis, the modern 3D X‐ray Computed Tomography (CT) approach is mostly used in soil physical studies related to soil functioning and ecological services. Aim: In this study, we interpret ancient soil formation of the Late Pleistocene pedosedimentary archive of the Tlalpan sequence in the State of Tlaxcala in Central Mexico, based on soil and sediment porosity distribution in 2D and 3D. Methods: In order to interpret ancient soil formation based on the porosity distribution, we applied both micromorphological (2D) and CT (3D) analyses in undisturbed samples of each horizon of the Tlalpan sequence. Results: Our micromorphological observations have shown that pore space arrangement is unique for each soil horizon and that it is predetermined by the dominant pedogenetical processes and their succession, such as bioturbation, clay illuviation, and vertic shrinking/swelling. Most of the channels formed by biogenic agents (roots and mesofauna) subsequently underwent shape deformations and/or refilling. The "accommodating planes" type of voids resulted from the development of features of vertic paleosols that, in some cases, erased the past pedogenic pore space organization. Although biogenic turbation, compaction, and clay illuviation mostly affected the macro‐ and mesopores, shrinking/swelling processes affected macro‐ and mesoporosity distribution. The process that was only reflected at the microporosity level is hydroconsolidation. Conclusions: Despite the common idea that textural pores are more resistant to changes compared to meso‐ and macropores, most of soil formation processes registered in the Tlalpan sequence, including anthropogenic impact, were identified in macro‐ and mesopore space. Moreover, the changes that were registered in pore space transformation by 2D and 3D methods of analysis in undisturbed samples are crucial for identifying the sequence of formation processes and, therefore, for paleopedological interpretation. This study shows that the CT is a useful tool to access the soil formation, and pore space memory studied both in 3D and 2D is an important proxy for paleopedological research. [ABSTRACT FROM AUTHOR]

Epidemiology, prevention, early management of cervical spine trauma and it's reduction are the objectives of this review paper. A PubMed and MEDLINE search between 2009 and 2019 were conducted using keywords. Case reports, experimental studies, papers other than English language and and unrelated studies were excluded. Up-to-date information on epidemiology of spine trauma, prevention, early emergency management, transportation, and closed reduction were reviewed and statements were produced to reach a consensus in 2 separate consensus meeting of World Federation of Neurosurgical Societies (WFNS) Spine Committee. The statements were voted and reached a positive or negative consensus using Delphi method. Global incidence of traumatic spinal injury is higher in low- and middle-income countries. The most frequent reasons are road traffic accidents and falls. The incidence from low falls in the elderly are increasing in high-income countries due to ageing populations. Prevention needs legislative, engineering, educational, and social efforts that need common efforts of all society. Emergency care of the trauma patient, transportation, and in-hospital acute management should be planned by implementing detailed protocols to prevent further damage to the spinal cord. This review summarizes the WFNS Spine Committee recommendations on epidemiology, prevention, and early management of cervical spine injuries.

Objective to analyze the structure of motivational attitudes of nurse personnel and their career orientations. Materials and methods.The study was conducted on the basis of three multidisciplinary medical organizations in St. Petersburg. Nurses were asked to complete two questionnaires, including an assessment of motivation and career orientations. The total number of questionnaires processed was 162. The average length of service of the respondents was 10.5 years. According to age, the respondents were distributed as follows: 62.0% were people aged 20-29 years, approximately equal shares were people 30-39years old (18.6%) and 40 years and older (19.4%). The study of the motivation of professional activity was carried out according to the methodology of K. Zamfir (modified by A. Rean). Also, the methodology used to diagnose the value orientations in the career was ''Career Anchors'' (the method of E. Shein in adaptation by V.A. Chiker and V.E. Vinokurov). The questionnaires contain certain points and clues, allowing one to evaluate, respectively, the nature of motivation and preferred orientations. The statistical processing of collected data was performed with the Microsoft Оffice 2016 programs: Microsoft Word, Microsoft Excel. Results.It was established that in the structure of motivation, 40.2% is an external positive motivation (positive incentives in the organization), 30.1% is an internal motivation (satisfaction with work and its results), 19.7% is an external negative motivation (punishment). The main value orientations in a career are as follows. In the first place the integration of lifestyles (in 73.2% of cases, this orientation scored maximum points); on the second stability of work (62.0%); in the third place ministry (52.4%). The ratio of value orientations varies somewhat among people of different ages. Conclusion.The identified features of motivation and value orientations of nurses should be taken into account both as a whole (to develop a system of motivation in the organization) and personally, taking into account the individual characteristics of each employee. The study of motivation should be carried out by psychologists of medical organizations, and the results should be transmitted to managers to form a reasonable personnel policy.

The uncontrolled simultaneous application of prochlorperazine with typical phenothiazine derivatives antipsychotics and other drugs leads to fatal poisonings. Aim. To optimize TLC procedures for the screening examinations in combined poisonings with prochlorperazine and other drugs. Results and discussion. The chromatographic mobility of prochlorperazine, clorpromazine, ibuprofen, trifluoperazine and quetiapine has been studied on two types of plates (HPTLC and TLC). It has been shown that the TLC-systems used (special – for prochlorperazine, general – for screening of phenothiazine derivatives, as well as drug and narcotic substances of the basic nature recommended by the International Association of Forensic Toxicologists) rather effectively separate the substances analyzed in a thin layer of a sorbent, except for trifluoperazine. To detect the adsorption zones of substances, the Lieberman reagent giving different staining, the Dragendorff reagent and irradiation of chromatograms by UV-light (λ = 254 nm) have been proposed. The detection sensitivity is 0.5 – 1.0 μg in the sample. The validation assessment of the methods developed has been carried out by the chromatographic analysis of prochlorperazine model mixtures with each of the substances studied. Experimental part. The studies were carried out on HPTLC plates (silica gel 60G, particle size – 5 – 7 μm, substrate type – glass, Estonia) with 10 × 10 cm in size and Merck plates (silica gel 60G F254, particle size – 10 – 15 μm, substrate type – aluminum foil, Germany) with 10 × 10 cm in size. Conclusions. The TLC-conditions for screening of prochlorperazine, chlorpromazine, ibuprofen, trifluoperazin and quetiapine have been determined; they can be recommended for drugs detection in real samples of biological objects in the case of combined poisoning.

The integrated cavity absorption meter is designed to measure the seawater absorption coefficient spectra which are necessary for studying ocean productivity and heat balance. The performed numerical simulations of a light field structure made it possible to improve the measurement technique. Its results showed that the use of the Lambertian model allows to reduce the calculation time by two orders of magnitude with an acceptable loss of accuracy for these calculations. It is shown that in the case of an integrating sphere made of fluorilon, the use of different volume scattering functions does not affect the calculation result, which is not true in the case of using a sphere with a mirror coating. The effect of an air layer between quartz and fluorilon is considered, and the applicability of the diffusion approximation is verified. Examples of field measurements of the seawater absorption coefficient and its components performed in different water areas of the World Ocean in 2020–2022 are presented.