Publications by authors named "Mattia D"

380 Publications

Enzyme-Functionalized Cellulose Beads as a Promising Antimicrobial Material.

Biomacromolecules 2021 02 6;22(2):754-762. Epub 2021 Jan 6.

Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom.

The extensive use of antibiotics over the last decades is responsible for the emergence of multidrug-resistant (MDR) microorganisms that are challenging health care systems worldwide. The use of alternative antimicrobial materials could mitigate the selection of new MDR strains by reducing antibiotic overuse. This paper describes the design of enzyme-based antimicrobial cellulose beads containing a covalently coupled glucose oxidase from (GOx) able to release antimicrobial concentrations of hydrogen peroxide (HO) (≈ 1.8 mM). The material preparation was optimized to obtain the best performance in terms of mechanical resistance, shelf life, and HO production. As a proof of concept, agar inhibition halo assays (Kirby-Bauer test) against model pathogens were performed. The two most relevant factors affecting the bead functionalization process were the degree of oxidation and the pH used for the enzyme binding process. Slightly acidic conditions during the functionalization process (pH 6) showed the best results for the GOx/cellulose system. The functionalized beads inhibited the growth of all the microorganisms assayed, confirming the release of sufficient antimicrobial levels of HO. The maximum inhibition efficiency was exhibited toward () and (), although significant inhibitory effects toward methicillin-resistant (MRSA) and were also observed. These enzyme-functionalized cellulose beads represent an inexpensive, sustainable, and biocompatible antimicrobial material with potential use in many applications, including the manufacturing of biomedical products and additives for food preservation.
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http://dx.doi.org/10.1021/acs.biomac.0c01536DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884000PMC
February 2021

Multienzyme Cellulose Films as Sustainable and Self-Degradable Hydrogen Peroxide-Producing Material.

Biomacromolecules 2020 12 17;21(12):5315-5322. Epub 2020 Nov 17.

Department of Chemistry, University of Bath, Bath BA2 7AY, U.K.

The use of hydrogen peroxide-releasing enzymes as a component to produce alternative and sustainable antimicrobial materials has aroused interest in the scientific community. However, the preparation of such materials requires an effective enzyme binding method that often involves the use of expensive and toxic chemicals. Here, we describe the development of an enzyme-based hydrogen peroxide-producing regenerated cellulose film (RCF) in which a cellobiohydrolase (CBHI) and a cellobiose dehydrogenase (CDHA) were efficiently adsorbed, 90.38 ± 2.2 and 82.40 ± 5.7%, respectively, without making use of cross-linkers. The enzyme adsorption kinetics and binding isotherm experiments showed high affinity of the proteins possessing cellulose-binding modules for RCF, suggesting that binding on regenerated cellulose via specific interactions can be an alternative method for enzyme immobilization. Resistance to compression and porosity at a micrometer scale were found to be tunable by changing cellulose concentration prior to film regeneration. The self-degradation process, triggered by stacking CBHI and CDHA (previously immobilized onto separate RCF), produced 0.15 nmol/min·cm of HO. Moreover, the production of HO was sustained for at least 24 h reaching a concentration of ∼2 mM. The activity of CDHA immobilized on RCF was not affected by reuse for at least 3 days (1 cycle/day), suggesting that no significant enzyme leakage occurred in that timeframe. In the material herein designed, cellulose (regenerated from a 1-ethyl-3-methylimidazolium acetate/dimethyl sulfoxide (DMSO) solution) serves both as support and substrate for the immobilized enzymes. The sequential reaction led to the production of HO at a micromolar-millimolar level revealing the potential use of the material as a self-degradable antimicrobial agent.
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http://dx.doi.org/10.1021/acs.biomac.0c01393DOI Listing
December 2020

Enhanced nanoparticle rejection in aligned boron nitride nanotube membranes.

Nanoscale 2020 Oct;12(41):21138-21145

Department of Chemical Engineering and Centre for Advanced Separations Engineering, University of Bath, BA27AY, UK.

The rejection of particles with different charges and sizes, ranging from a few Ångstroms to tens of nanometers, is key to a wide range of industrial applications, from wastewater treatment to product purification in biotech processes. Carbon nanotubes (CNTs) have long held the promise to revolutionize filtration, with orders of magnitude higher fluxes compared to commercial membranes. CNTs, however, can only reject particles and ions wider than their internal diameter. In this work, the fabrication of aligned boron nitride nanotube (BNNT) membranes capable of rejecting nanoparticles smaller than their internal diameter is reported for the first time. This is due to a mechanism of charge-based rejection in addition to the size-based one, enabled by the BNNTs surface structure and chemistry and elucidated here using high fidelity molecular dynamics and Brownian dynamics simulations. This results in ∼40% higher rejection of the same particles by BNNT membranes than CNT ones with comparable nanotube diameter. Furthermore, since permeance is proportional to the square of the nanotubes' diameter, using BNNT membranes with ∼30% larger nanotube diameter than a CNT membrane with comparable rejection would result in up to 70% higher permeance. These results open the way to the design of more effective nanotube membranes, capable of high particle rejection and, at the same time, high water permeance.
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http://dx.doi.org/10.1039/d0nr04058dDOI Listing
October 2020

Multicenter prospective study on predictors of short-term outcome in disorders of consciousness.

Neurology 2020 09 13;95(11):e1488-e1499. Epub 2020 Jul 13.

From IRCCS Fondazione Don Carlo Gnocchi (A.E., A.G., A.M.R.), Florence; Istituti Clinici Scientifici Maugeri IRCCS (S.F.), SB S.p.A., Laboratorio di Valutazione Multimodale dei Disordini della Coscienza, Telese Terme (BN); Department of Psychology (A.M., L.T.), University of Campania L. Vanvitelli, Caserta; Fondazione Santa Lucia IRCCS (R.F., D.M.), Rome, Italy; Neurosurgery Department (E.A.), University of Athens Medical School, Greece; Coma Science Group (H.C., A.T., O.G.), GIGA Consciousness, University and University Hospital of Liège, Belgium; Neurorehabilitation and Vegetative State Unit (G.L.), E. Viglietta, Cuneo, Italy; NEURORHB-Servicio de Neurorrehabilitación de Hospitales Vithas (E.N.), Valencia, Spain; Unit of Neurophysiology and Unit for Severe Acquired Brain Injuries (S.B.), Rehabilitation Department, Giuseppe Giglio Foundation, Cefalù, Italy; Center for Neurotechnology and Neurorecovery (B.L.E., C.C.), Department of Neurology, Massachusetts General Hospital, Boston; CHN William Lennox (N.L.), Ottignies, Belgium; Department of Psychology (V.V.), University of Reading Malaysia; Neurorehabilitation Unit (M.B.), HABILITA Zingonia/Ciserano, Bergamo; Department of Computer, Control and Management Engineering (J.T.), Sapienza University of Rome, Italy; Concussion Care Centre of Virginia, Ltd. (N.Z.), Richmond; and Research Institute (C.S.), Casa Colina Hospital and Centers for Healthcare, Pomona, CA.

Objective: This international multicenter, prospective, observational study aimed at identifying predictors of short-term clinical outcome in patients with prolonged disorders of consciousness (DoC) due to acquired severe brain injury.

Methods: Patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally conscious state (MCS) were enrolled within 3 months from their brain injury in 12 specialized medical institutions. Demographic, anamnestic, clinical, and neurophysiologic data were collected at study entry. Patients were then followed up for assessing the primary outcome, that is, clinical diagnosis according to standardized criteria at 6 months postinjury.

Results: We enrolled 147 patients (44 women; mean age 49.4 [95% confidence interval 46.1-52.6] years; VS/UWS 71, MCS 76; traumatic 55, vascular 56, anoxic 36; mean time postinjury 59.6 [55.4-63.6] days). The 6-month follow-up was complete for 143 patients (VS/UWS 70; MCS 73). With respect to study entry, the clinical diagnosis improved in 72 patients (VS/UWS 27; MCS 45). Younger age, shorter time postinjury, higher Coma Recovery Scale-Revised total score, and presence of EEG reactivity to eye opening at study entry predicted better outcome, whereas etiology, clinical diagnosis, Disability Rating Scale score, EEG background activity, acoustic reactivity, and P300 on event-related potentials were not associated with outcome.

Conclusions: Multimodal assessment could identify patients with higher likelihood of clinical improvement in order to help clinicians, families, and funding sources with various aspects of decision-making. This multicenter, international study aims to stimulate further research that drives international consensus regarding standardization of prognostic procedures for patients with DoC.
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http://dx.doi.org/10.1212/WNL.0000000000010254DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7713739PMC
September 2020

The Promotoer, a brain-computer interface-assisted intervention to promote upper limb functional motor recovery after stroke: a study protocol for a randomized controlled trial to test early and long-term efficacy and to identify determinants of response.

BMC Neurol 2020 Jun 27;20(1):254. Epub 2020 Jun 27.

Fondazione Santa Lucia, IRCCS, Rome, Italy.

Background: Stroke is a leading cause of long-term disability. Cost-effective post-stroke rehabilitation programs for upper limb are critically needed. Brain-Computer Interfaces (BCIs) which enable the modulation of Electroencephalography (EEG) sensorimotor rhythms are promising tools to promote post-stroke recovery of upper limb motor function. The "Promotoer" study intends to boost the application of the EEG-based BCIs in clinical practice providing evidence for a short/long-term efficacy in enhancing post-stroke hand functional motor recovery and quantifiable indices of the participants response to a BCI-based intervention. To these aims, a longitudinal study will be performed in which subacute stroke participants will undergo a hand motor imagery (MI) training assisted by the Promotoer system, an EEG-based BCI system fully compliant with rehabilitation requirements.

Methods: This longitudinal 2-arm randomized controlled superiority trial will include 48 first ever, unilateral, subacute stroke participants, randomly assigned to 2 intervention groups: the BCI-assisted hand MI training and a hand MI training not supported by BCI. Both interventions are delivered (3 weekly session; 6 weeks) as add-on regimen to standard intensive rehabilitation. A multidimensional assessment will be performed at: randomization/pre-intervention, 48 h post-intervention, and at 1, 3 and 6 month/s after end of intervention. Primary outcome measure is the Fugl-Meyer Assessment (FMA, upper extremity) at 48 h post-intervention. Secondary outcome measures include: the upper extremity FMA at follow-up, the Modified Ashworth Scale, the Numeric Rating Scale for pain, the Action Research Arm Test, the National Institute of Health Stroke Scale, the Manual Muscle Test, all collected at the different timepoints as well as neurophysiological and neuroimaging measures.

Discussion: We expect the BCI-based rewarding of hand MI practice to promote long-lasting retention of the early induced improvement in hand motor outcome and also, this clinical improvement to be sustained by a long-lasting neuroplasticity changes harnessed by the BCI-based intervention. Furthermore, the longitudinal multidimensional assessment will address the selection of those stroke participants who best benefit of a BCI-assisted therapy, consistently advancing the transfer of BCIs to a best clinical practice.

Trial Registration: Name of registry: BCI-assisted MI Intervention in Subacute Stroke (Promotoer).

Trial Registration Number: NCT04353297 ; registration date on the ClinicalTrial.gov platform: April, 15/2020.
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http://dx.doi.org/10.1186/s12883-020-01826-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7320550PMC
June 2020

Brain-computer interfaces in neurologic rehabilitation practice.

Handb Clin Neurol 2020 ;168:101-116

Neuroelectrical Imaging and Brain Computer Interface Laboratory, Fondazione Santa Lucia IRCCS, Rome, Italy. Electronic address:

The brain-computer interfaces (BCIs) for neurologic rehabilitation are based on the assumption that by retraining the brain to specific activities, an ultimate improvement of function can be expected. In this chapter, we review the present status, key determinants, and future directions of the clinical use of BCI in neurorehabilitation. The recent advancements in noninvasive BCIs as a therapeutic tool to promote functional motor recovery by inducing neuroplasticity are described, focusing on stroke as it represents the major cause of long-term motor disability. The relevance of recent findings on BCI use in spinal cord injury beyond the control of neuroprosthetic devices to restore motor function is briefly discussed. In a dedicated section, we examine the potential role of BCI technology in the domain of cognitive function recovery by instantiating BCIs in the long history of neurofeedback and some emerging BCI paradigms to address cognitive rehabilitation are highlighted. Despite the knowledge acquired over the last decade and the growing number of studies providing evidence for clinical efficacy of BCI in motor rehabilitation, an exhaustive deployment of this technology in clinical practice is still on its way. The pipeline to translate BCI to clinical practice in neurorehabilitation is the subject of this chapter.
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http://dx.doi.org/10.1016/B978-0-444-63934-9.00009-3DOI Listing
December 2020

Shedding Light Onto the Nature of Iron Decorated Graphene and Graphite Oxide Nanohybrids for CO Conversion at Atmospheric Pressure.

ChemistryOpen 2020 02 14;9(2):242-252. Epub 2020 Feb 14.

Department of Chemistry University of Bath Claverton Down BA2 7AY UK.

We report on the design and testing of new graphite and graphene oxide-based extended π-conjugated synthetic scaffolds for applications in sustainable chemistry transformations. Nanoparticle-functionalised carbonaceous catalysts for new Fischer Tropsch and Reverse GasWater Shift (RGWS) transformations were prepared: functional graphene oxides emerged from graphite powders via an adapted Hummer's method and subsequently impregnated with uniform-sized nanoparticles. Then the resulting nanomaterials were imaged by TEM, SEM, EDX, AFM and characterised by IR, XPS and Raman spectroscopies prior to incorporation of Pd(II) promoters and further microscopic and spectroscopic analysis. Newly synthesised 2D and 3D layered nanostructures incorporating carbon-supported iron oxide nanoparticulate pre-catalysts were tested, upon hydrogen reduction for the conversion of CO to CO as well as for the selective formation of CH and longer chain hydrocarbons. The reduction reaction was also carried out and the catalytic species isolated and fully characterised. The catalytic activity of a graphene oxide-supported iron oxide pre-catalyst converted CO into hydrocarbons at different temperatures (305, 335, 370 and 405 °C), and its activity compared well with that of the analogues supported on graphite oxide, the 3-dimensional material precursor to the graphene oxide. Investigation into the use of graphene oxide as a framework for catalysis showed that it has promising activity with respect to reverse gas water shift (RWGS) reaction of CO to CO, even at the low levels of catalyst used and under the rather mild conditions employed at atmospheric pressure. Whilst the γ-FeO decorated graphene oxide-based pre-catalyst displays fairly constant activity up to 405 °C, it was found by GC-MS analysis to be unstable with respect to decomposition at higher temperatures. The addition of palladium as a promoter increased the activity of the iron functionalised graphite oxide in the RWGS. The activity of graphene oxide supported catalysts was found to be enhanced with respect to that of iron-functionalised graphite oxide with, or without palladium as a promoter, and comparable to that of Fe@carbon nanotube-based systems tested under analogous conditions. These results display a significant step forward for the catalytic activity estimations for the iron functionalised and rapidly processable and scalable graphene oxide. The hereby investigated phenomena are of particular relevance for the understanding of the intimate surface morphologies and the potential role of non-covalent interactions in the iron oxide-graphene oxide networks, which could inform the design of nano-materials with performance in future sustainable catalysis applications.
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http://dx.doi.org/10.1002/open.201900368DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7020623PMC
February 2020

Single-trial Connectivity Estimation through the Least Absolute Shrinkage and Selection Operator.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:6422-6425

Methods based on the use of multivariate autoregressive models (MVAR) have proved to be an accurate tool for the estimation of functional links between the activity originated in different brain regions. A well-established method for the parameters estimation is the Ordinary Least Square (OLS) approach, followed by an assessment procedure that can be performed by means of Asymptotic Statistic (AS). However, the performances of both procedures are strongly influenced by the number of data samples available, thus limiting the conditions in which brain connectivity can be estimated. The aim of this paper is to introduce and test a regression method based on Least Absolute Shrinkage and Selection Operator (LASSO) to broaden the estimation of brain connectivity to those conditions in which current methods fail due to the limited data points available. We tested the performances of the LASSO regression in a simulation study under different levels of data points available, in comparison with a classical approach based on OLS and AS. Then, the two methods were applied to real electroencephalographic (EEG) signals, recorded during a motor imagery task. The simulation study and the application to real EEG data both indicated that LASSO regression provides better performances than the currently used methodologies for the estimation of brain connectivity when few data points are available. This work paves the way to the estimation and assessment of connectivity patterns with limited data amount and in on-line settings.
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http://dx.doi.org/10.1109/EMBC.2019.8857909DOI Listing
July 2019

Adaptive learning in the detection of Movement Related Cortical Potentials improves usability of associative Brain-Computer Interfaces.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:3079-3082

Brain-computer interfaces have increasingly found applications in motor function recovery in stroke patients. In this context, it has been demonstrated that associative-BCI protocols, implemented by means the movement related cortical potentials (MRCPs), induce significant cortical plasticity. To date, no methods have been proposed to deal with brain signal (i.e. MRCP feature) non-stationarity. This study introduces adaptive learning methods in MRCP detection and aims at comparing a no-adaptive approach based on the Locality Sensitive Discriminant Analysis (LSDA) with three LSDA-based adaptive approaches. As a proof of concept, EEG and force data were collected from six healthy subjects while performing isometric ankle dorsiflexion. Results revealed that adaptive algorithms increase the number of true detections and decrease the number of false positives per minute. Moreover, the markedly reduction of BCI system calibration time suggests that these methods have the potential to improve the usability of associative-BCI in post-stroke motor recovery.
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http://dx.doi.org/10.1109/EMBC.2019.8856580DOI Listing
July 2019

Estimation of brain connectivity through Artificial Neural Networks.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:636-639

Among different methods available for estimating brain connectivity from electroencephalographic signals (EEG), those based on MVAR models have proved to be flexible and accurate. They rely on the solution of linear equations that can be pursued through artificial neural networks (ANNs) used as MVAR model. However, when few data samples are available, there is a lack of accuracy in estimating MVAR parameters due to the collinearity between regressors. Moreover, the assessment procedure is also affected by the lack of data points. The mathematical solution to these problems is represented by penalized regression methods based on l norm, that can reduce collinearity by means of variable selection process. However, the direct application of l norm during the training of an ANN does not result in an efficient learning process. With the introduction of the stochastic gradient descent-L1 (SGD-L1) it is possible to apply l norm directly on the estimated weights in an efficient way. Even if ANNs has been used as MVAR model for brain connectivity estimation, the use of SGD-L1 algorithm has never been tested to this purpose when few data samples are available. In this work, we tested an approach based on ANNs and SGD-L1 on both surrogate and real EEG data. Our results show that ANNs can provide accurate brain connectivity estimation if trained with SGD-L1 algorithm even when few data samples are available.
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http://dx.doi.org/10.1109/EMBC.2019.8856585DOI Listing
July 2019

The Optimal Setting for Multilayer Modularity Optimization in Multilayer Brain Networks.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:624-627

Community detection plays a key role in the study of brain networks, as mechanisms of modular integration and segregation are known to characterize the brain functioning. Moreover, brain networks are intrinsically multilayer: they can vary across time, frequency, subjects, conditions, and meaning, according to different definitions of connectivity. Several algorithms for the multilayer community detection were defined to identify communities in time-varying networks. The most used one is based on the optimization of a multilayer formulation of the modularity, in which two parameters linked to the spatial (γ) and temporal (ω) resolution of the uncovered communities can be set. While the effect of different γ-values has been largely explored, which ω-values are most suitable to different purposes and conditions is still an open issue. In this work, we test the algorithm performances under different values of ω by means of ad hoc implemented benchmark graphs that cover a wide range of conditions. Results provide a guide to the choice of the ω-values according to the network features. Finally, we show an application of the algorithm to real functional brain networks estimated from electro-encephalographic (EEG) signals collected at rest with closed and open eyes. The application to real data agrees with the results of the simulation study and confirms the conclusion drawn from it.
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http://dx.doi.org/10.1109/EMBC.2019.8856674DOI Listing
July 2019

Influences of the biofeedback content on robotic post-stroke gait rehabilitation: electromyographic vs joint torque biofeedback.

J Neuroeng Rehabil 2019 07 23;16(1):95. Epub 2019 Jul 23.

Spinal Rehabilitation Laboratory - Neurological and Spinal Cord Injury Rehabilitation Department A, Santa Lucia Foundation IRCCS, Via Ardeatina 306 -, 00179, Rome, Italy.

Background: Add-on robot-mediated therapy has proven to be more effective than conventional therapy alone in post-stroke gait rehabilitation. Such robot-mediated interventions routinely use also visual biofeedback tools. A better understanding of biofeedback content effects when used for robotic locomotor training may improve the rehabilitation process and outcomes.

Methods: This randomized cross-over pilot trial aimed to address the possible impact of different biofeedback contents on patients' performance and experience during Lokomat training, by comparing a novel biofeedback based on online biological electromyographic information (EMGb) versus the commercial joint torque biofeedback (Rb) in sub-acute non ambulatory patients. 12 patients were randomized into two treatment groups, A and B, based on two different biofeedback training. For both groups, study protocol consisted of 12 Lokomat sessions, 6 for each biofeedback condition, 40 min each, 3 sessions per week of frequency. All patients performed Lokomat trainings as an add-on therapy to the conventional one that was the same for both groups and consisted of 40 min per day, 5 days per week. The primary outcome was the Modified Ashworth Spasticity Scale, and secondary outcomes included clinical, neurological, mechanical, and personal experience variables collected before and after each biofeedback training.

Results: Lokomat training significantly improved gait/daily living activity independence and trunk control, nevertheless, different effects due to biofeedback content were remarked. EMGb was more effective to reduce spasticity and improve muscle force at the ankle, knee and hip joints. Robot data suggest that Rb induces more adaptation to robotic movements than EMGb. Furthermore, Rb was perceived less demanding than EMGb, even though patient motivation was higher for EMGb. Robot was perceived to be effective, easy to use, reliable and safe: acceptability was rated as very high by all patients.

Conclusions: Specific effects can be related to biofeedback content: when muscular-based information is used, a more direct effect on lower limb spasticity and muscle activity is evidenced. In a similar manner, when biofeedback treatment is based on joint torque data, a higher patient compliance effect in terms of force exerted is achieved. Subjects who underwent EMGb seemed to be more motivated than those treated with Rb.
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http://dx.doi.org/10.1186/s12984-019-0558-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6652021PMC
July 2019

3D Printed Fouling-Resistant Composite Membranes.

ACS Appl Mater Interfaces 2019 Jul 11;11(29):26373-26383. Epub 2019 Jul 11.

Department of Chemical Engineering, Centre for Advanced Separations Engineering , University of Bath , Claverton Down, Bath BA2 7AY , U.K.

Fouling remains a long-standing unsolved problem that hinders the widespread use of membrane applications in industry. This article reports the use of numerical simulations coupled with extensive material synthesis and characterization to fabricate fouling-resistant 3D printed composite membranes. The membranes consist of a thin polyethersulfone selective layer deposited onto a 3D printed flat and double sinusoidal (wavy) support. Fouling and cleaning of the composite membranes were tested by using bovine serum albumin solution in a cross-flow ultrafiltration setup. The transmembrane pressure was regulated at 1 bar and the cross-flow Reynolds number () varied between 400 and 1000. In comparison to the flat membrane, the wavy membrane showed superior performance in terms of pure water permeance (PWP) (10% higher) and permeance recovery ratio (87% vs 53%) after the first filtration cycle at = 1000. Prolong testing showed that the wavy membrane could retain approximately 87% of its initial PWP after 10 complete filtration cycles. This impressive fouling-resistant behavior is attributed to the localized fluid turbulence induced by the 3D printed wavy structure. These results show that not only the lifetime of membrane operations could be favorably extended but also the operational costs and environmental damage of membrane-based processes could also be significantly reduced.
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http://dx.doi.org/10.1021/acsami.9b07764DOI Listing
July 2019

Enhancing the photo-corrosion resistance of ZnO nanowire photocatalysts.

J Hazard Mater 2019 10 19;378:120799. Epub 2019 Jun 19.

Centre for Sustainable Chemical Technologies, University of Bath, BA27AY, UK; Department of Chemical Engineering, University of Bath, BA27AY, UK. Electronic address:

Zinc oxide (ZnO) displays superior properties as a photocatalyst, compared to the more widely used TiO. However, widespread application of ZnO is hampered by its high photo-corrosion in aqueous environments under UV irradiation. A systematic investigation of the effect of (i) post-production annealing, (ii) dissolved oxygen levels during photocatalysis and (iii) reactor configuration on the stability and photocatalytic activity (PCA) of ZnO nanowires, grown on either flat or circular supports, was conducted. Results show, for the first time, that it is possible to significantly enhance the photo-corrosion resistance of ZnO in water under UV irradiation while also increasing PCA. Oxygen plasma post-annealing of ZnO nanowire films led to a 46% higher photocatalytic degradation of phenol compared to as-produced films. In oxygen-saturated solutions, both thermally and oxygen plasma annealed ZnO revealed similar photo-corrosion resistance. Switching from a batch to a flow-through reactor, tripled phenol photodegradation under the same irradiation conditions from 19 to 57% due to enhanced mass transfer, while significantly increasing the stability and re-usability of the ZnO, with 5 repeat uses over 3 days showing no decrease in PCA. These results pave the way to more widespread use of photo-corrosion resistant ZnO in the degradation of organic pollutants in water.
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http://dx.doi.org/10.1016/j.jhazmat.2019.120799DOI Listing
October 2019

Language-Related Brain Potentials in Patients With Disorders of Consciousness: A Follow-up Study to Detect "Covert" Language Disorders.

Neurorehabil Neural Repair 2019 07 23;33(7):513-522. Epub 2019 May 23.

1 IRCCS Fondazione Santa Lucia, Rome, Italy.

Language disorders may occur in patients with disorders of consciousness (DoCs), and they could interfere with the behavioral assessment of consciousness and responsiveness. Objective. In this study, we retrospectively explored whether ERP N400 was eventually associated with the presence of aphasia diagnosed in those patients who had evolved into Exit-Minimally Conscious State (E-MCS) at the clinical follow-up. In this retrospective cohort study, the ERPs elicited by an auditory sentences task were retrospectively examined in a sample of 15 DoC patients diagnosed according to the Coma Recovery Scale-Revised (CRS-R). All these 15 DoC patients underwent a (at least) 1-year clinical follow-up, which included a neuropsychological evaluation to assess language function among other cognitive functions. Ten healthy individuals also underwent the same paradigm to investigate the variability of ERPs characteristics. The N400 ERP component with centroparietal topography was found in 9 of 10 healthy controls in response to the ill-formed sentences. Analysis of patients' data revealed that (1) a significant N400 component could be detected in 64% (9 of 14 patients) of the DoC patients regardless of the type of DoC; (2) no significant N400 ERP component was retrospectively detected in those E-MCS patients who showed aphasia at the follow-up; and (3) the presence/absence of the N400-ERP component was consistent with the brain lesion side and significantly predict the recovery. These preliminary findings indicate that the absence of N400 was significantly associated with the presence of aphasia diagnosed at the clinical follow-up in E-MCS patients.
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http://dx.doi.org/10.1177/1545968319846123DOI Listing
July 2019

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics.

Ecology 2019 07 23;100(7):e02663. Epub 2019 Apr 23.

Xenarthrans-anteaters, sloths, and armadillos-have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.
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http://dx.doi.org/10.1002/ecy.2663DOI Listing
July 2019

Leishmania spp. in Perianal Adenoma in a Dog: A Case Report.

Top Companion Anim Med 2019 Mar 20;34:33-35. Epub 2018 Dec 20.

Vets Now Referrals, Swindon, United Kingdom.

The coexistence of Leishmania and neoplasia is rarely reported in humans or animals. An 11-year-old intact male mixed-breed dog was presented with a well-demarcated perianal nodule. Cytologic and histopathologic examinations were consistent with the diagnosis of perianal gland adenoma with the presence of Leishmania amastigotes. The dog was considered to be in leishmaniasis stage C (clinically diseased) based on clinical signs, laboratory findings, and serological status. A novel finding in this case report was the presence of Leishmania within the perianal adenoma, probably resulting from an atypical dissemination of the parasites.
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http://dx.doi.org/10.1053/j.tcam.2018.12.004DOI Listing
March 2019

Atypical Presentation of Ertapenum-Associated Hallucinations in a Patient With Psychiatric Disease.

J Clin Psychopharmacol 2019 Jan/Feb;39(1):88-89

Creighton University School of Medicine-Phoenix Regional Campus Phoenix, AZ Department of Psychiatry St. Joseph's Hospital and Medical Center Phoenix, AZ

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http://dx.doi.org/10.1097/JCP.0000000000000996DOI Listing
February 2019

Surface-Controlled Water Flow in Nanotube Membranes.

ACS Appl Mater Interfaces 2019 Jan 21;11(1):1689-1698. Epub 2018 Dec 21.

Department of Chemical Engineering and Centre for Advanced Separations Engineering , University of Bath , Bath BA2 7AY , U.K.

The independent effect of nanotube surface chemistry and structure on the flow of water under nanoscale confinement is demonstrated in this paper for the first time via the synthesis of novel carbon nitride nanotube (CNNT) membranes. Using a combination of experiments and high-fidelity molecular dynamics (MD) simulations, it is shown here that the hydrophilization of the sp carbon structure, induced by the presence of the C-N bonds, decreases the pure water permeance in CNNTs when compared with pristine and turbostratic carbon nanotubes (CNTs). The MD simulations are based on a model true to the chemical structure of the synthesized nanotubes, built from spectroscopy measurements and calibrated potentials using droplet experiments. The effect on permeance is explained in terms of solid-liquid interactions at the nanotube wall with increased water viscosity and decreased surface diffusion near the CNNT wall, when compared to CNTs. A model directly linking the solid-liquid interactions to the water permeance is presented, showing good agreement with both experiments and MD simulations. This work opens the way to tailoring surface chemistry and structure inside nanotube membranes for a wide range of transport and separation processes.
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http://dx.doi.org/10.1021/acsami.8b18532DOI Listing
January 2019

Comparison of two inoculation methods for Microsporum canis culture using the toothbrush sampling technique.

Vet Dermatol 2019 Feb 10;30(1):60-e17. Epub 2018 Dec 10.

Dipartimento Scienze Veterinarie, Università di Torino, Largo Palo Braccini 2, 10095, Grugliasco, Torino, Italy.

Background: The fungal culture toothbrush method is a common method for obtaining material for fungal cultures to diagnose dermatophytosis. The optimal technique for inoculation onto the agar surface has not been studied.

Hypothesis/objectives: To compare two inoculation techniques; the first involved pressing the toothbrush onto the plate surface (Procedure A) and the second involved pressing the toothbrush onto the agar, as well as transferring hairs and scales entrapped in the bristles. (Procedure B). The hypothesis was that transferring hairs onto the plate would increase the likelihood of obtaining positive cultures.

Animals: Twenty-six cattery-housed cats were sampled using the toothbrush technique. Two toothbrush samples were obtained from each cat.

Methods And Materials: The two toothbrush samples from each cat were randomized to Procedure A or B, and the investigator was blinded to inoculation technique. Cultures were performed on a medium specific for dermatophytes. The number of positive plates, and the presence and abundance of colonies of dermatophytes and contaminant moulds were compared between the two techniques.

Results: Twenty-one cats were culture-positive for Microsporum canis. Procedure A resulted in a significantly higher number (P < 0.01) of positive plates (20 of 21; 95%) compared with Procedure B (seven of 21; 33%). These results were due mainly to higher plate invasion by contaminant moulds, using Procedure B.

Conclusions And Clinical Importance: Based upon the findings of this study, the optimum inoculation technique is to press toothbrush bristles onto agar plates to maximize growth of M. canis and minimize introduction of contaminant inoculation.
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http://dx.doi.org/10.1111/vde.12705DOI Listing
February 2019

On the Relationship Between Attention Processing and P300-Based Brain Computer Interface Control in Amyotrophic Lateral Sclerosis.

Front Hum Neurosci 2018 28;12:165. Epub 2018 May 28.

Neuroelectrical Imaging and BCI Laboratory, NeiLab, Fondazione Santa Lucia (IRCCS), Rome, Italy.

Our objective was to investigate the capacity to control a P3-based brain-computer interface (BCI) device for communication and its related (temporal) attention processing in a sample of amyotrophic lateral sclerosis (ALS) patients with respect to healthy subjects. The ultimate goal was to corroborate the role of cognitive mechanisms in event-related potential (ERP)-based BCI control in ALS patients. Furthermore, the possible differences in such attentional mechanisms between the two groups were investigated in order to unveil possible alterations associated with the ALS condition. Thirteen ALS patients and 13 healthy volunteers matched for age and years of education underwent a P3-speller BCI task and a rapid serial visual presentation (RSVP) task. The RSVP task was performed by participants in order to screen their temporal pattern of attentional resource allocation, namely: (i) the temporal attentional filtering capacity (scored as T1%); and (ii) the capability to adequately update the attentive filter in the temporal dynamics of the attentional selection (scored as T2%). For the P3-speller BCI task, the online accuracy and information transfer rate (ITR) were obtained. Centroid Latency and Mean Amplitude of N200 and P300 were also obtained. No significant differences emerged between ALS patients and Controls with regards to online accuracy ( = 0.13). Differently, the performance in controlling the P3-speller expressed as ITR values (calculated offline) were compromised in ALS patients ( < 0.05), with a delay in the latency of P3 when processing BCI stimuli as compared with Control group ( < 0.01). Furthermore, the temporal aspect of attentional filtering which was related to BCI control ( = 0.51; < 0.05) and to the P3 wave amplitude ( = 0.63; < 0.05) was also altered in ALS patients ( = 0.01). These findings ground the knowledge required to develop sensible classes of BCI specifically designed by taking into account the influence of the cognitive characteristics of the possible candidates in need of a BCI system for communication.
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http://dx.doi.org/10.3389/fnhum.2018.00165DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5985322PMC
May 2018

Bean Seedling Growth Enhancement Using Magnetite Nanoparticles.

J Agric Food Chem 2018 Jun 4;66(23):5746-5755. Epub 2018 Jun 4.

Laboratory of Nuclear Instrumentation (LIN), Center for Nuclear Energy in Agriculture (CENA) , University of São Paulo (USP) , Piracicaba , São Paulo 13416000 , Brazil.

Advanced fertilizers are one of the top requirements to address rising global food demand. This study investigates the effect of bare and polyethylene glycol-coated FeO nanoparticles on the germination and seedling development of Phaseolus vulgaris L. Although the germination rate was not affected by the treatments (1 to 1 000 mg Fe L), seed soaking in FeO-PEG at 1 000 mg Fe L increased radicle elongation (8.1 ± 1.1 cm vs 5.9 ± 1.0 cm for the control). Conversely, Fe/Fe and bare FeO at 1 000 mg Fe L prevented the growth. X-ray spectroscopy and tomography showed that Fe penetrated in the seed. Enzymatic assays showed that FeO-PEG was the least harmful treatment to α-amylase. The growth promoted by the FeO-PEG might be related to water uptake enhancement induced by the PEG coating. These results show the potential of using coated iron nanoparticles to enhance the growth of common food crops.
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http://dx.doi.org/10.1021/acs.jafc.8b00557DOI Listing
June 2018

A retrospective histopathological, immunohistochemical and molecular study of the presence of Leishmania spp. in the skin of cats with head and neck ulcerative dermatitis.

Vet Dermatol 2018 Jun 25;29(3):212-e76. Epub 2018 Mar 25.

Veterinaria Cetego, Via M.C. Cetego 20, 00177, Rome, Italy.

Background: Head and neck ulcers in cats can arise from allergic and nonallergic disorders, including feline leishmaniosis (FeL). It is important to rule out this aetiological agent in regions that are endemic for canine leishmaniosis, because the drugs used to treat immune-mediated disorders of cats can be contraindicated in the setting of infection.

Hypothesis/objectives: The aim of this study was to evaluate the skin of cats with ulcerative dermatitis of the head or neck for evidence of Leishmania infection using combined immunohistochemistry (IHC) and Polymerase Chain Reaction (PCR). An IHC for tissue histiocytes was also utilized because leishmaniosis may provoke a histiocytic inflammatory response.

Animals: Twenty seven cats with head and/or neck ulcers.

Methods: Skin biopsy specimens were examined for the presence of Leishmania spp. by routine histopathological evaluation and IHC using a polyclonal anti-Leishmania antibody, and by quantitative PCR (qPCR). The ionized calcium-binding adapter molecule-1 (IBA-1) antibody was used to immunolocalize histiocytes. Selected history and clinical data were recorded.

Results: All specimens showed a superficial mid-perivascular mixed inflammatory infiltrate. The presence of histiocytes was confirmed in 23 of 27 cases with the IBA-1 antibody. Immunohistochemistry and qPCR techniques confirmed the absence of Leishmania in all cases.

Conclusions And Clinical Importance: Leishmania did not seem to play a role in the pathogenesis of feline ulcerative dermatitis of the head and neck in the subjects studied, despite a lifestyle potentially associated with infection. Histiocytic infiltration of tissue is not a specific marker for Leishmania infection in this population.
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http://dx.doi.org/10.1111/vde.12535DOI Listing
June 2018

Multiscale design of ZnO nanostructured photocatalysts.

Phys Chem Chem Phys 2018 Feb;20(9):6648-6656

Department of Chemical Engineering, University of Bath, BA27AY, UK.

A systematic investigation of the photocatalytic activity (PCA) of nanostructured ZnO films showed how this is directly affected by the films' morphology at different scales, from the macroscale morphology of films (e.g. thickness and surface area), to the microscale feature arrangement (e.g. aligned vs. randomly oriented structures or interpenetrated ones), to the nanoscale structure (e.g. crystal size and orientation). The interest in immobilizing photocatalysts in water treatment stems from concerns about the potential toxicity of their slurry form, which requires expensive downstream removal. Immobilisation, though, leads to a reduction in PCA, generally attributed to a lower surface area. By reducing the films' feature size to the nanoscale, an immobilized photocatalyst with high surface area can be achieved. At this scale, however, feature structuring and morphology become important as they determine the interaction between light and the photocatalytic material. In this work, nanostructured ZnO films with different morphology, arrangement and structure were produced by electrochemical anodization of zinc and were tested using the degradation of phenol in a batch reactor as a model system. Results show that the PCA for immobilized catalysts can be optimised by controlling microscale arrangement (light absorbance capacity) and nanoscale structure (crystal size and orientation) rather than macroscale morphology (surface area). These results provide a clear direction to maximising the photocatalytic activity of immobilised photocatalysts for the removal of organic pollutants from water.
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http://dx.doi.org/10.1039/c7cp07984bDOI Listing
February 2018

Different Topological Properties of EEG-Derived Networks Describe Working Memory Phases as Revealed by Graph Theoretical Analysis.

Front Hum Neurosci 2017 12;11:637. Epub 2018 Jan 12.

Neuroelectrical Imaging and Brain-Computer Interface Laboratory, Fondazione Santa Lucia IRCCS, Rome, Italy.

Several non-invasive imaging methods have contributed to shed light on the brain mechanisms underlying working memory (WM). The aim of the present study was to depict the topology of the relevant EEG-derived brain networks associated to distinct operations of WM function elicited by the Sternberg Item Recognition Task (SIRT) such as encoding, storage, and retrieval in healthy, middle age (46 ± 5 years) adults. High density EEG recordings were performed in 17 participants whilst attending a visual SIRT. Neural correlates of WM were assessed by means of a combination of EEG signal processing methods (i.e., time-varying connectivity estimation and graph theory), in order to extract synthetic descriptors of the complex networks underlying the encoding, storage, and retrieval phases of WM construct. The group analysis revealed that the encoding phase exhibited a significantly higher topology of EEG networks with respect to storage and retrieval in all EEG frequency oscillations, thus indicating that during the encoding of items the global network organization could "" promote the information flow between WM sub-networks. We also found that the magnitude of such configuration could predict subject behavioral performance when memory load increases as indicated by the negative correlation between Reaction Time and the values estimated during the encoding in the alpha band in both 4 and 6 digits conditions. At the local scale, the values of the which measures the degree of in- and out- information flow between scalp areas were found to specifically distinguish the within the relevant sub-networks associated to each of the three different WM phases, according to the different role of the sub-network of regions in the different WM phases. Our findings indicate that the use of EEG-derived connectivity measures and their related topological indices might offer a reliable and yet affordable approach to monitor WM components and thus theoretically support the clinical assessment of cognitive functions in presence of WM decline/impairment, as it occurs after stroke.
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http://dx.doi.org/10.3389/fnhum.2017.00637DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5770976PMC
January 2018

Sustainable Synthesis of Oxalic and Succinic Acid through Aerobic Oxidation of C6 Polyols Under Mild Conditions.

ChemSusChem 2018 03 23;11(6):1073-1081. Epub 2018 Feb 23.

CIRCC, Via Celso Ulpiani, 27, 70126, Bari, Italy.

The sustainable chemical industry encompasses a shift from the use of fossil carbon to renewable carbon. The synthesis of chemicals from nonedible biomass (cellulosic or oil) represents one of the key steps for "greening" the chemical industry. In this paper, we report the aerobic oxidative cleavage of C6 polyols (5-HMF, glucose, fructose and sucrose) to oxalic acid (OA) and succinic acid (SA) in water under mild conditions using M@CNT and M@NCNT (M=Fe, V; CNT=carbon nanotubes; NCNT=N-doped CNT), which, under suitable conditions, were recoverable and reusable without any loss of efficiency. The influence of the temperature, O pressure (PO2 ), reaction time and stirring rate are discussed and the best reaction conditions are determined for an almost complete conversion of the starting material and a good OA yield of 48 %. SA and formic acid were the only co-products. The former could be further converted into OA by oxidation in the presence of formic acid, resulting in an overall OA yield of >62 %. This process was clean and did not produce organic waste nor gas emissions.
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http://dx.doi.org/10.1002/cssc.201702347DOI Listing
March 2018

An EEG index of sensorimotor interhemispheric coupling after unilateral stroke: clinical and neurophysiological study.

Eur J Neurosci 2018 01 11;47(2):158-163. Epub 2018 Jan 11.

Neuroelectrical Imaging and BCI Laboratory, Fondazione Santa Lucia, IRCCS, Via Ardeatina, 306 00179, Rome, Italy.

Brain connectivity has been employed to investigate on post-stroke recovery mechanisms and assess the effect of specific rehabilitation interventions. Changes in interhemispheric coupling after stroke have been related to the extent of damage in the corticospinal tract (CST) and thus, to motor impairment. In this study, we aimed at defining an index of interhemispheric connectivity derived from electroencephalography (EEG), correlated with CST integrity and clinical impairment. Thirty sub-acute stroke patients underwent clinical and neurophysiological evaluation: CST integrity was assessed by Transcranial Magnetic Stimulation and high-density EEG was recorded at rest. Connectivity was assessed by means of Partial Directed Coherence and the normalized Inter-Hemispheric Strength (nIHS) was calculated for each patient and frequency band on the whole network and in three sub-networks relative to the frontal, central (sensorimotor) and occipital areas. Interhemipheric coupling as expressed by nIHS on the whole network was significantly higher in patients with preserved CST integrity in beta and gamma bands. The same index estimated for the three sub-networks showed significant differences only in the sensorimotor area in lower beta, with higher values in patients with preserved CST integrity. The sensorimotor lower beta nIHS showed a significant positive correlation with clinical impairment. We propose an EEG-based connectivity index which is a measure of the interhemispheric cross-talking and correlates with functional motor impairment in subacute stroke patients. Such index could be employed to evaluate the effects of training aimed at re-establishing interhemispheric balance and eventually drive the design of future connectivity-driven rehabilitation interventions.
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http://dx.doi.org/10.1111/ejn.13797DOI Listing
January 2018

Workshops of the Sixth International Brain-Computer Interface Meeting: brain-computer interfaces past, present, and future.

Brain Comput Interfaces (Abingdon) 2017 30;4(1-2):3-36. Epub 2017 Jan 30.

Brain Center Rudolf Magnus, Dept Neurology and Neurosurgery, University Medical Center Utrecht, Utrecht, The Netherlands.

The Sixth International Brain-Computer Interface (BCI) Meeting was held 30 May-3 June 2016 at the Asilomar Conference Grounds, Pacific Grove, California, USA. The conference included 28 workshops covering topics in BCI and brain-machine interface research. Topics included BCI for specific populations or applications, advancing BCI research through use of specific signals or technological advances, and translational and commercial issues to bring both implanted and non-invasive BCIs to market. BCI research is growing and expanding in the breadth of its applications, the depth of knowledge it can produce, and the practical benefit it can provide both for those with physical impairments and the general public. Here we provide summaries of each workshop, illustrating the breadth and depth of BCI research and highlighting important issues and calls for action to support future research and development.
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http://dx.doi.org/10.1080/2326263X.2016.1275488DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5693371PMC
January 2017

Transcranial cerebellar direct current stimulation: Effects on brain resting state oscillatory and network activity.

Annu Int Conf IEEE Eng Med Biol Soc 2017 Jul;2017:4359-4362

Transcranial cerebellar direct current stimulation (tcDCS) can offer new insights into the cerebellar function and disorders, by modulating noninvasively the activity of cerebellar networks. Taking into account the functional interplay between the cerebellum and the cerebral cortex, we addressed the effects of unilateral tcDCS (active electrode positioned over the right cerebellar hemisphere) on the electroencephalographic (EEG) oscillatory activity and on the cortical network organization at resting state. Effects on spectral (de)synchronizations and functional connectivity after anodal and cathodal stimulation were assessed with respect to a sham condition. A lateralized synchronization over the sensorimotor area in gamma band, as well as an increase of the network segregation in sensory-motor rhythms and a higher communication between hemispheres in gamma band, were detected after anodal stimulation. The same measures after cathodal tcDCS returned responses similar to the sham condition.
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http://dx.doi.org/10.1109/EMBC.2017.8037821DOI Listing
July 2017

Estimating brain connectivity when few data points are available: Perspectives and limitations.

Annu Int Conf IEEE Eng Med Biol Soc 2017 Jul;2017:4351-4354

Methods based on the use of multivariate autoregressive modeling (MVAR) have proved to be an accurate and flexible tool for the estimation of brain functional connectivity. The multivariate approach, however, implies the use of a model whose complexity (in terms of number of parameters) increases quadratically with the number of signals included in the problem. This can often lead to an underdetermined problem and to the condition of multicollinearity. The aim of this paper is to introduce and test an approach based on Ridge Regression combined with a modified version of the statistics usually adopted for these methods, to broaden the estimation of brain connectivity to those conditions in which current methods fail, due to the lack of enough data points. We tested the performances of this new approach, in comparison with the classical approach based on ordinary least squares (OLS), by means of a simulation study implementing different ground-truth networks, under different network sizes and different levels of data points. Simulation results showed that the new approach provides better performances, in terms of accuracy of the parameters estimation and false positives/false negatives rates, in all conditions related to a low data points/model dimension ratio, and may thus be exploited to estimate and validate estimated patterns at single-trial level or when short time data segments are available.
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http://dx.doi.org/10.1109/EMBC.2017.8037819DOI Listing
July 2017