Pupil dilation response (PDR) has been proposed as a physiological marker of conscious access to a stimulus or its attributes, such as novelty. In a previous study on healthy volunteers, we adapted ...the auditory "local global" paradigm and showed that violations of global regularity elicited a PDR. Notably without instructions, this global effect was present only in participants who could consciously report violations of global regularities. In the present study, we used a similar approach in 24 non-communicating patients affected with a Disorder of Consciousness (DoC) and compared PDR to ERPs regarding diagnostic and prognostic performance. At the group level, global effect could not be detected in DoC patients. At the individual level, the only patient with a PDR global effect was in a MCS and recovered consciousness at 6 months. Contrasting the most regular trials to the most irregular ones improved PDR's diagnostic and prognostic power in DoC patients. Pupillometry is a promising tool but requires several methodological improvements to enhance the signal-to-noise ratio and make it more robust for probing consciousness and cognition in DoC patients.
Disorders of consciousness (DoC) are severe neurological conditions in which consciousness is impaired to various degrees. They are caused by injury or malfunction of neural systems regulating ...arousal and awareness. Over the last decades, major efforts in improving and individualizing diagnostic and prognostic accuracy for patients affected by DoC have been made, mainly focusing on introducing multimodal assessments to complement behavioral examination. The present EU-funded multicentric research project "PerBrain" is aimed at developing an individualized diagnostic hierarchical pathway guided by both behavior and multimodal neurodiagnostics for DoC patients.
In this project, each enrolled patient undergoes repetitive behavioral, clinical, and neurodiagnostic assessments according to a patient-tailored multi-layer workflow. Multimodal diagnostic acquisitions using state-of-the-art techniques at different stages of the patients' clinical evolution are performed. The techniques applied comprise well-established behavioral scales, innovative neurophysiological techniques (such as quantitative electroencephalography and transcranial magnetic stimulation combined with electroencephalography), structural and resting-state functional magnetic resonance imaging, and measurements of physiological activity (i.e. nasal airflow respiration). In addition, the well-being and treatment decision attitudes of patients' informal caregivers (primarily family members) are investigated. Patient and caregiver assessments are performed at multiple time points within one year after acquired brain injury, starting at the acute disease phase.
Accurate classification and outcome prediction of DoC are of crucial importance for affected patients as well as their caregivers, as individual rehabilitation strategies and treatment decisions are critically dependent on the latter. The PerBrain project aims at optimizing individual DoC diagnosis and accuracy of outcome prediction by integrating data from the suggested multimodal examination methods into a personalized hierarchical diagnosis and prognosis procedure. Using the parallel tracking of both patients' neurological status and their caregivers' mental situation, well-being, and treatment decision attitudes from the acute to the chronic phase of the disease and across different countries, this project aims at significantly contributing to the current clinical routine of DoC patients and their family members.
ClinicalTrials.gov, NCT04798456 . Registered 15 March 2021 - Retrospectively registered.
We report the synthesis of CdSe/CdS rod in rod core/shell heterostructures. These rods, synthesized using a seeded-growth approach, show narrow distributions of rod diameters and lengths and exhibit ...high emission quantum efficiencies and highly polarized emission. The degree of polarization is controlled by the inner core rod dimensions, and it is equal or up to 1.5 times higher than the polarization of equivalent sphere in rod systems. Using the method of photoselection we measure the polarization anisotropy at different excitation wavelengths and study the interplay between electronic contribution and dielectric effects in determining the absorption and emission polarization.
There has been a growing interest in the role of pre-stimulus oscillations on cortical excitability in visual and motor systems. Prior studies focused on the relationship between pre-stimulus ...neuronal activity and TMS-evoked motor evoked potentials (MEPs) have reported heterogeneous results. We aimed to assess the role of pre-stimulus neural activity on the latency of MEPs, which might enhance our understanding of the variability of MEP signals, and potentially provide information on the role played by cortical activity fluctuations in the excitability of corticospinal pathways. Near-threshold single-pulse TMS (spTMS) was applied at random intervals over the primary motor cortex of 14 healthy participants while they sat passively, to trigger hand muscle contractions. Multichannel EEG was recorded during spTMS blocks. Spearman correlations between both the variation in MEP onset latencies and peak-to-peak MEP amplitudes, and the pre-stimulus power of EEG oscillations were calculated across participants. We found that the variation in MEP latency was positively correlated with pre-stimulus power in the theta range (4–7 Hz) in a broad time window (− 3.1 to − 1.9 s) preceding the spTMS generating the MEP. No correlation between pre-stimulus power in any frequency band and MEP amplitude was found. Our results show that pre-stimulus theta oscillations are correlated with the variation in MEP latency, an outcome measure determined by fiber conduction velocity and synaptic delays along the corticospinal tract. This finding could prove useful for clinicians using MEP latency-based information in pre- or intra-operative diagnostics of corticospinal impairment.
•Heterostructure semiconductor nanorods show unique dimensionality related properties.•Ongoing progress in synthesis extends the variety of compositions and structures.•Optoelectronic properties of ...heterostructured nanorods are derived from their shape.•These unique properties make nanorods attractive for a variety of applications.
A fascinating phenomenon which characterizes semiconductors in the nanoscale regime is the ability to control the physical properties of the system through its dimensionality, as was demonstrated for a large number of systems including 2D quantum wells, 1D nanowires, and 0D quantum dots. Heterostructured nanorods, which are composed of two or more semiconductors, present an exciting example for a system in which the physical properties are strongly influenced by the 1D nature of the entire particle, but also incorporate the effects of the dimensionality, dimensions, and composition of each component on its own.
The ongoing progress in colloidal synthesis of nanocrystals allows nowadays to synthesize a variety of heterostructured nanorods with different compositions and structures, ranging from seeded nanorods to rods with asymmetric spatial compositions. The unique properties of these systems, with reduced and mixed dimensionality, attract a growing interest from the scientific point of view, and are also attractive for a range of applications including solid state lighting, lasers, light emitting diodes, flat panel displays, bio-labeling, and solar cells.
In this paper we review the growing family of heterostructured nanorods, analyze the factors which determine their physical properties and in particular their optical characteristics, and discuss the potential applications of these systems in different technologies.
Type 2 diabetic peripheral neuropathy is known to cause balance limitations in static, dynamic, and functional activity. The Mini-BESTest, a shortened version of BESTest, was evolved to identify ...balance disorders within a short duration. No prior studies have yet been conducted to assess the usefulness of Mini-BESTest in the diagnosis of type 2 diabetic peripheral neuropathy. The current study aimed to examine the reliability and discriminant validity by comparing the Mini-BESTest scores between type 2 diabetic patients with peripheral neuropathy, divided into two 2 groups based on reporting scores of <4 and ≥4 in the MNSI questionnaire, respectively. Therefore, a cross-sectional study design was conducted including 44 type 2 diabetic patients (4 males and 40 females; aged 56.61 ± 7.7 years old). Diabetic peripheral neuropathy was diagnosed by physical assessment using the Michigan Neuropathy Screening Instrument (MNSI). Inter-rater (two physiotherapists) and Intra-rater (7−10 days) reliability of the Mini-BESTest were explored with intraclass correlation coefficients (ICC2,1) and (ICC3,1). The Mini-BESTest presented an excellent inter-rater reliability (ICC2,1= 0.95, 95% CI = 0.91−0.97, SEM = 0.61) and an excellent intra-rater reliability (ICC3,1 = 0.93, 95% CI = 0.87−0.96, SEM = 0.66), with confirmation by a good agreement presented by the Bland−Altman plots. The internal consistency measured with the overall Cronbach’s alpha showed an acceptable agreement (0.73). The MDC was 2.16. In addition, the Mini-BESTest scores in the type 2 diabetic neuropathy patients reporting MNSI questionnaire scores <4 was found to be significantly higher when compared with those reporting scores ≥4. The Mini-BESTest can be used as a highly reliable and valid clinical application in the population with type 2 diabetic peripheral neuropathy.
Brain states are frequently represented using a unidimensional scale measuring the richness of subjective experience (level of consciousness). This description assumes a mapping between the ...high-dimensional space of whole-brain configurations and the trajectories of brain states associated with changes in consciousness, yet this mapping and its properties remain unclear. We combine whole-brain modeling, data augmentation, and deep learning for dimensionality reduction to determine a mapping representing states of consciousness in a low-dimensional space, where distances parallel similarities between states. An orderly trajectory from wakefulness to patients with brain injury is revealed in a latent space whose coordinates represent metrics related to functional modularity and structure-function coupling, increasing alongside loss of consciousness. Finally, we investigate the effects of model perturbations, providing geometrical interpretation for the stability and reversibility of states. We conclude that conscious awareness depends on functional patterns encoded as a low-dimensional trajectory within the vast space of brain configurations.
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•The brain spontaneously self-organizes into a discrete number of global brain states•Level of consciousness refers to a scalar index determined by the behavior of those states•Whole-brain model and deep learning allow algorithmic dimension reduction of brain states•Low-dimensional space reveals an orderly organization of brain states and its transitions
Despite the microscale complexity, the brain self-organizes into a discrete number of global brain states characterized by specific behavioral patterns. Perl et al. use whole-brain models and deep learning algorithms to obtain a low-dimensional representation not only in terms of behavioral data but based on objective quantification of neuroimaging data.
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•White broad band emission from α-Y2Si2O7activated with Yb3+ and Er3+.•Strong power dependencies of the white light.•Bright white light generation under atmospheric pressure.
White up ...conversion emission has been observed in sol–gel derived α-Y2Si2O7 nano powders activated with ytterbium and erbium ions when excited with the 950nm emission of a laser diode. Measurements of the sample emission intensity dependence on the pumping power under atmospheric pressure condition were performed to provide possibly an explanation for the UC mechanism. The emission intensities of each Er3+ transition decreased when the pumping power was increased from 1.7 to 2.5W with the observation of the bright wide band under atmospheric pressure condition. When the sample was subject to very low pressure at 0.03mbar and the pumping power was set from 0.9 to 2.5W, the white emission brightness increased. The CIE coordinates (x, y) for YSYE were found to be (0.330, 0.300 (1.7W–0.3mbar)) and (0.339, 0.304 (2.5W–atmospheric pressure)) under the 950nm laser diode excitation.
This article provides an up-to-date overview of breast cancer mammography screening and briefly discusses its history, controversies, current guidelines, practices across Asia, and future directions. ...An emphasis is made on shared decision-making--instead of giving just a 'yes' or 'no' answer to patients, the focus should be on providing sufficient information about the pros and cons of screening to help women make a personal, informed choice. Frontline experts, including breast surgeons, oncologists, breast radiologists, and their representative professional associations should all participate in guideline panels, with the goal of improving cancer detection, reducing mortality, and improving patient outcome.
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