741 research outputs found

    EEG correlation at a distance: a re-analysis of two studies using a machine learning approach

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    Background: In this paper, data from two studies relative to the relationship between the electroencephalogram (EEG) activities of two isolated and physically separated subjects were re-analyzed using machine-learning algorithms. The first dataset comprises the data of 25 pairs of participants where one member of each pair was stimulated with a visual and an auditory 500 Hz signals of 1 second duration. The second dataset consisted of the data of 20 pairs of participants where one member of each pair received visual and auditory stimulation lasting 1 second duration with on-off modulation at 10, 12, and 14 Hz. Methods and Results: Applying a 'linear discriminant classifier' to the first dataset, it was possible to correctly classify 50.74% of the EEG activity of non-stimulated participants, correlated to the remote sensorial stimulation of the distant partner. In the second dataset, the percentage of correctly classified EEG activity in the non-stimulated partners was 51.17%, 50.45% and 51.91%, respectively, for the 10, 12, and 14 Hz stimulations, with respect the condition of no stimulation in the distant partner. Conclusions: The analysis of EEG activity using machine-learning algorithms has produced advances in the study of the connection between the EEG activities of the stimulated partner and the isolated distant partner, opening new insight into the possibility to devise practical application for non-conventional "mental telecommunications" between physically and sensorially separated participants

    A new method to detect event-related potentials based on Pearson's correlation

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    Event-related potentials (ERPs) are widely used in brain-computer interface applications and in neuroscience. Normal EEG activity is rich in background noise, and therefore, in order to detect ERPs, it is usually necessary to take the average from multiple trials to reduce the effects of this noise. The noise produced by EEG activity itself is not correlated with the ERP waveform and so, by calculating the average, the noise is decreased by a factor inversely proportional to the square root of N, where N is the number of averaged epochs. This is the easiest strategy currently used to detect ERPs, which is based on calculating the average of all ERP's waveform, these waveforms being time- and phase-locked. In this paper, a new method called GW6 is proposed, which calculates the ERP using a mathematical method based only on Pearson's correlation. The result is a graph with the same time resolution as the classical ERP and which shows only positive peaks representing the increase-in consonance with the stimuli-in EEG signal correlation over all channels. This new method is also useful for selectively identifying and highlighting some hidden components of the ERP response that are not phase-locked, and that are usually hidden in the standard and simple method based on the averaging of all the epochs. These hidden components seem to be caused by variations (between each successive stimulus) of the ERP's inherent phase latency period (jitter), although the same stimulus across all EEG channels produces a reasonably constant phase. For this reason, this new method could be very helpful to investigate these hidden components of the ERP response and to develop applications for scientific and medical purposes. Moreover, this new method is more resistant to EEG artifacts than the standard calculations of the average and could be very useful in research and neurology. The method we are proposing can be directly used in the form of a process written in the well-known Matlab programming language and can be easily and quickly written in any other software language

    Importance of Sexual Function Assessment in Multidimensional Evaluation of AGHD Patients: Results from the MAGHD Study.

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    Background: Adult growth hormone deficiency (AGHD) is a debilitating clinical condition leading to decreased quality of life (QoL). The impact of reduced muscle mass, weakening and loss of vitality on QoL have been well characterized in AGHD. The impact of AGHD on sexual function, a recognized factor able to modify well-being, has never been investigated. Aim: To investigate the prevalence of sexual dysfunction in AGHD patients referring to a single endocrinological center and grouped according to their his- tory of r-hGH therapy.Methods: The Management of Adult Growth Hormone Deficiency (MAGHD) Study is a pro- spective, real-life trial aiming to improve management of AGHD patients through a smartphone app (MAGHD App)and a wearable device. The 83 AGHD enrolled patients (31 Females, 52 Males, mean age 56.27 + 14.68 years) were divided in 3 groups (G) according to r-hGH therapy: on long-term r-hGH therapy (G1, n=32), previously treated with r-hGH (G2, n=20), never treated (G3, n=31). Within the first phase of the study, a large database was created collecting clinical, biochemical and psychological data. In addition to QLS-H and QoL-AGHDA routinely used to as- sess QoL, IIEF-15 and FSFI were employed to evaluate sexual function in males and females, respectively. The nonparametric Kruskal-Wallis test was used for compar- ison among 3 groups.Results: Here only baseline data of the MAGHD Study are presented.According to IIEF-15 results, the prevalence of erectile dysfunction (ED) in male AGHD cohort was 60%. Erectile function (EF) score was signifi- cantly higher in G1 compared to both G2 and G3 (p < 0.05) with an ED prevalence of 35% in G1, 75% in G2 and 75% in G3. Even excluding patients with serum testosterone lower than 2 ng/ml and older than 65 years, ED prevalence did not change significantly in the 3 groups. Moreover, EF do- main was inversely and directly correlated to age (R20.130, β-0.360) and IGF1 levels (R20.156, β0.395), respectively. The prevalence of female sexual dysfunction according to FSFI was 89.3%. Even though desire, arousal, lubrication and overall scores were significantly higher (better results) in G1 compared to G2 and G3 (p < 0.05), no correlation resulted between FSFI domains and IGF1 levels. Instead an inverse correlation resulted between desire domain and age.Conclusions: This study, performed in a real-life clinical setting, demonstrates a high prevalence of sexual dysfunc- tion in AGHD patients and that r-hGH treatment seems to be associated to better sexual outcomes. These results suggest that the evaluation of sexual function should be in- tegrated in the global assessment of AGHD patients since sexual activity is a fundamental domain able to influence both well-being and QoL

    Targeting cytosolic proliferating cell nuclear antigen in neutrophil-dominated inflammation.

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    New therapeutic approaches that can accelerate neutrophil apoptosis under inflammatory conditions to enhance the resolution of inflammation are now under study. Neutrophils are deprived of proliferative capacity and have a tightly controlled lifespan to avoid their persistence at the site of injury. We have recently described that the proliferating cell nuclear antigen (PCNA), a nuclear factor involved in DNA replication and repair of proliferating cells is a key regulator of neutrophil survival. The nuclear-to-cytoplasmic relocalization occurred during granulocytic differentiation and is dependent on a nuclear export sequence thus strongly suggesting that PCNA has physiologic cytoplasmic functions. In this review, we will try to put into perspective the physiologic relevance of PCNA in neutrophils. We will discuss key issues such as molecular structure, post-translational modifications, based on our knowledge of nuclear PCNA, assuming that similar principles governing its function are conserved between nuclear and cytosolic PCNA. The example of cystic fibrosis that features one of the most intense neutrophil-dominated pulmonary inflammation will be discussed. We believe that through an intimate comprehension of the cytosolic PCNA scaffold based on nuclear PCNA knowledge, novel pathways regulating neutrophil survival can be unraveled and innovative agents can be developed to dampen inflammation where it proves detrimental

    Life cycle assessment of hydrogen-powered city buses in the High V.LO-City project: integrating vehicle operation and refuelling infrastructure

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    During the project High V.LO-City, which ended in December 2019, 14 hydrogen fuel cell buses were operated in four European cities. This paper aims at presenting total emissions through the lifetime of fuel cell buses with different hydrogen production options, including the refuelling stations. The environmental assessment of such bus system is carried out using the life cycle assessment methodology. Three hydrogen production pathways are investigated: water electrolysis, chlor-alkali electrolysis and steam methane reforming. Fuel economy during bus operation is around 10.25 KgH2/100 km, and the refuelling station energy demand ranges between 7 and 9 KWh/KgH2. To support the inventory stage, dedicated software tools were developed for collecting and processing a huge amount of bus data and refuelling station performance, for automating data entry and for impacts calculation. The results show that hydrogen-powered buses, compared to a diesel bus, have the potential to reduce emissions during the use phase, if renewables resources are used. On the other hand, impacts from the vehicle production, including battery pack and fuel cell stack, still dominate environmental load. Consequently, improving the emission profile of fuel cell bus system requires to promote clean electricity sources to supply a low-carbon hydrogen and to sharpen policy focus regarding life cycle management and to counter potential setbacks, in particular those related to problem shifting and to grid improvement. For hazardous emissions and resource use, the high energy intensity of mining and refining activities still poses challenges on how to further enhance the environmental advantages of fuel cells and battery packs

    Nanoparticle transport across the blood brain barrier

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    ABSTRACT: While the role of the blood-brain barrier (BBB) is increasingly recognized in the (development of treatments targeting neurodegenerative disorders, to date, few strategies exist that enable drug delivery of non-BBB crossing molecules directly to their site of action, the brain. However, the recent advent of Nanomedicines may provide a potent tool to implement CNS targeted delivery of active compounds. Approaches for BBB crossing are deeply investigated in relation to the pathology: among the main important diseases of the CNS, this review focuses on the application of nanomedicines to neurodegenerative disorders (Alzheimer, Parkinson and Huntington's Disease) and to other brain pathologies as epilepsy, infectious diseases, multiple sclerosis, lysosomal storage disorders, strokes

    EEG correlates of social interaction at distance

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    This study investigated EEG correlates of social interaction at distance between twenty-five pairs of participants who were not connected by any traditional channels of communication. Each session involved the application of 128 stimulations separated by intervals of random duration ranging from 4 to 6 seconds. One of the pair received a one-second stimulation from a light signal produced by an arrangement of red LEDs, and a simultaneous 500 Hz sinusoidal audio signal of the same length. The other member of the pair sat in an isolated sound-proof room, such that any sensory interaction between the pair was impossible. An analysis of the Event-Related Potentials associated with sensory stimulation using traditional averaging methods showed a distinct peak at approximately 300 ms, but only in the EEG activity of subjects who were directly stimulated. However, when a new algorithm was applied to the EEG activity based on the correlation between signals from all active electrodes, a weak but robust response was also detected in the EEG activity of the passive member of the pair, particularly within 9 – 10 Hz in the Alpha range. Using the Bootstrap method and the Monte Carlo emulation, this signal was found to be statistically significant

    Model risk and techniques for controlling market parameters

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    The increasing use of internal market models for market risk assessment andmanagement promotes, in compliance with Basel II, better risk managementpractices but introduces at the same time the so called model risk. In the light of themany open issues connected to market risk, the aim of this paper is twofold. First, itoffers a formal analysis of model risk which is aimed to clarify quantification issuesand to illustrate the architecture of a control process for this type of risk. Animportant building block of such an architecture is the so called market parameterscontrol process, which is the focus of the present paper and consists of two differentphases: the definition of the data sources and the data retrieval forms, and thedefinition of the techniques for valuing variables (i.e. input model data) based onmarket data. Second, this paper proposes a market parameters control process and its implementation within an important Italian bank, namely Gruppo Banco Popolare.Specifically, by focusing on equity market risk, this paper illustrates the whole organization process needed to set up and implement the market parameters control techniques, which imply first controlling for integrity (existence, domain, homogeneity) and outliers and then performing benchmarking activities. Special emphasis is placed on the so-called second level parameters, which do not have official quotes and still are fundamental especially in valuing non linear positions (e.g. volatility). These activities are based on mathematical-statistical models, whose implementation has required the development of specific software and IT solutions and the adoption of an articulate organizational structure

    Impaired testicular signaling of vitamin A and vitamin K contributes to the aberrant composition of the extracellular matrix in idiopathic germ cell aplasia

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    Objective: To study pathogenic features of the somatic testicular microenvironment associated with idiopathic germ cell aplasia. Design: Cross-sectional study. Setting: Tertiary referral center for reproductive medicine. Patient(s): Testicular specimens from men with idiopathic nonobstructive azoospermia (iNOA) prospectively submitted to microdissection testicular sperm extraction. Of 20 specimens used for histology, 10 were also available for proteomic analysis. Primary Sertoli cells with normal karyotype and phenotype were also used. Intervention(s): Patients with iNOA were dichotomized according to a positive versus negative sperm retrieval at microdissection testicular sperm extraction, and on the isolated extracellular matrix (ECM) the proteomic analysis was performed. Main Outcome Measure(s): Proteomic analysis of the ECM from testicular specimens with positive versus negative sperm retrieval. Gene ontology enrichment was used to identify upstream regulators based on the 11 deregulated ECM proteins, which were validated by immunohistochemistry and quantitative polymerase chain reaction. Continuous variables were expressed as medians and interquartile range. Result(s): Germ cell aplasia was characterized by an increased signaling of the retinoic acid in Sertoli cells and associated with decreased expression of the basal membrane markers nidogen-2 and heparan sulfate proteoglycan-2. Decreased levels of the interstitial matrisome-associated factor IX and its regulator VKORC1 were, instead, coupled with decreased signaling of vitamin K in Leydig cells. An altered expression of a further eight ECM proteins was also found, including laminin-4 and laminin-5. Peripheral levels of the two vitamins were within the reference range in the two cohorts of iNOA men. Conclusion(s): We identified the pathogenetic signature of the somatic human testicular microenvironment, providing two vitamin-related mechanistic insights related to the molecular determinants of the idiopathic germ cell aplasia
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