Search

Background: Noninvasive neuromonitoring in critically ill children includes multiple modalities that all intend to improve our understanding of acute and ongoing brain injury. Methods: In this article, we review basic methods and devices, applications in clinical care and research, and explore potential future directions for three noninvasive neuromonitoring modalities in the pediatric intensive care unit: automated pupillometry, near-infrared spectroscopy, and transcranial Doppler ultrasonography. Results: All three technologies are noninvasive, portable, and easily repeatable to allow for serial measurements and trending of data over time. However, a paucity of high-quality data supporting the clinical utility of any of these technologies in critically ill children is currently a major limitation to their widespread application in the pediatric intensive care unit. Conclusions: Future prospective multicenter work addressing major knowledge gaps is necessary to advance the field of pediatric noninvasive neuromonitoring. [ABSTRACT FROM AUTHOR]

Polymer nanocomposites have garnered significant interest for electromagnetic interference (EMI) shielding applications due to their lightweight, anticorrosive and tunable properties. Employing the solution blending technique, we have developed a composite material comprising an 80wt% EMA (Ethylene–Methyl Acrylate) and 20wt% TPO (Thermoplastic Polyolefin) co-continuous blend. The incorporation of Reduced Graphene Oxide (RGO) as a conductive filler is achieved through precise confinement within the EMA phase of the polymer matrix. The selective placement of the RGO nanosheets within the EMA phase results in a dual percolation phenomenon, significantly lowering the electrical percolation threshold. A notable EMI SE value of -29.66 dB and electrical conductivity of 10–3 S/cm is acheived with the addition of 5wt% RGO. Further optimizing the composite, a loading of 15wt% RGO showcases an outstanding EMI SE of -39.06 dB. Moreover, this composite demonstrates commendable thermal conductivity of 0.75 W/m.K, alongside promising mechanical properties. The findings offer a promising avenue for the integration of this material in EMI-sensitive applications, particularly in the realms of stretchable and wearable electronics, offering effective thermal management and proficient microwave shielding capabilities. [ABSTRACT FROM AUTHOR]

Thermal pyrolysis of waste tires is an industrially beneficial method for material and energy recovery. Pyrolytic carbon black (CBp) is considered to be the secondary main product of this process. In the present study, an eco-friendly and economically feasible autoclave reactor-based thermal pyrolysis method was employed for the pyrolysis of waste tire tread. The average yields obtained for CBp and pyrolytic liquid are 48.2 wt% and 46.3 wt%, respectively. This CBp was well characterized by several techniques and results were compared with those of commercially available N330 carbon black. Elemental analysis shows that CBp has higher oxygen (O) and sulfur (S) content. Furthermore, the surface attachment of ash with carbon black from morphological analysis reveals the presence of higher ash content in CBp, which is further justified by proximate and thermal analysis. Zinc oxide (ZnO) plays a vital role in sulfur vulcanization and is added during the compounding stage of the tire-manufacturing process. Results obtained from TEM–EDX analysis indicate the presence of ZnO in the carbon black derived from thermal pyrolysis. Prior to conducting further research in this area, we may draw the conclusion from the experimental results that the obtained CBp has similar characteristic features and can be used in place of commercially available carbon black for the manufacture of rubber products. [ABSTRACT FROM AUTHOR]

The past decade has witnessed a variety of members of the carbon family along with exposure of carbon dots due to their magnificent properties in sensing, bioimaging, catalytic applications, biomedical fields, and so on. Herein, we report the simple hydrothermal method to fabricate photoluminescent doped carbon quantum dots for the detection of noxious lead(II) ions. Lead(II) ion is very venomous for both the environment and human health for which its detection is demanded area in the research field. The as-prepared carbon dots show excellent photostability, low toxicity and significant photoluminescence properties along with good water solubility. Along with these properties, carbon dots have a quantum yield of approximately 15%. In the practical field of application, these carbon dots have been used as sensing probes for the detection of lead(II) ions with a detection limit of 60 nmol·L−1. The fluorescence intensity of carbon dots was remarkably quenched in the presence of the lead(II) ion selectively among all the tested metal ions. Furthermore, we have studied the Stern–Volmer relationship for lead(II) quenching along with the explanation of the probable quenching mechanism. Ability of the doped carbon dots in heavy metal ions sensing in an environmental sample was demonstrated. [ABSTRACT FROM AUTHOR]

Clay-reinforced polymer composites have been considered as highly demand nanocomposites since several decades. To be utilized as packaging materials, these nanocomposites should possess good impermeability to oxygen and water vapor. The major compatibility issue of the hydrophilic inorganic nanofillers with hydrophobic thermoplastics has been overcome in this work by using the 'grafting to' silylation method of two different nanoclays, namely montmorillonite Na+ and halloysite (HNT) nanoclays, at 85 ℃. Organosilanes: 3-aminopropyltriethoxysilane (3-APTES) and vinyltrimethoxysilane (VTMS) were used to functionalize these nanoclays to improve interfacial bonding with linear low-density polyethylene (LLDPE) polymer chains. TGA analysis resulted in higher amount of grafting yield percentages for silane-treated MMT nanoclays (28.9% for MMT-APTES and 24.3% for MMT-VTMS) which are much higher than silane-functionalized HNT nanoclays. The amount of 1, 3 and 5 wt% of each organoclay was melt and mixed with LLDPE to enhance the overall performance properties of the resultant nanocomposites. The maximum tensile strength exhibited by the nanocomposite is around 20.6 MPa for 3 wt% of MMT-APTES concentration. Also, Young modulus improves up to 56% compared to neat LLDPE on the addition of 5 wt% of silane-treated organoclay. The microscopic analysis, especially TEM, provided information about the better dispersion of anisotropic fillers inside the thermoplastic matrix. Moreover, such filler compatibilization also showed 29.4% reduction in oxygen transmission rate (OTR) and 63.5% reduction in water vapor transmission rate (WVTR) value of composite materials with only 5 wt% of nanoclay loading along with improved rheological and ultraviolet (UV) barrier properties of these nanocomposites. The prepared nanocomposites with improved barrier properties could be ideal alternatives for flexible thermoplastic composites as packaging materials. Silane functionalization of nanoclays led to uniform distribution of clay in LLDPE matrix which improved mechanical and barrier properties of nanocomposites. [ABSTRACT FROM AUTHOR]

The solvent mixing process is a utile production technique to promote the cost-effective preparation of lightweight and flexible electromagnetic interference (EMI) shield films based on binary polymer-based conductive nanocomposite material with a very low electrical percolation threshold. Here in, a facile preparation of conductive binary biodegradable polymer nanocomposite films comprised of ester-based thermoplastic polyurethane (TPU), and poly (butylene adipate -co-terephthalate) (PBAT) is reported where the acid-functionalized multiwalled carbon nanotube (MO) has been preferentially incorporated into the PBAT phase of the binary polymer matrix and to get effective nanofiller dispersion we employed solvent mixing technique. For the effective reduction of “e-wastes” biodegradability is new generation demand for polymer nanocomposites. The PBAT/TPU based biodegradable binary blend has not been used before to fabricate polymer nanocomposite material. The 0.8 mm thick polymer nanocomposite film with the loading of around 5 wt% of MO is considered as the nanocomposite film achieving the electrical percolation threshold indicated by a sudden jump in the total EMI shielding effectiveness (EMI SE) value from − 17 to − 24 dB (within the frequency region from 8.2to 12.4 GHz) if the MO content is upgraded from 3 to 5 wt%. A loading of 10 wt% of MO gives − 30 dB of EMI SE at 8.2 GHz. The preferential distribution of MO filler in the PBAT phase has been confirmed by FTIR, DMA, selective dissolution test, HRTEM, and FESEM characterization techniques. [ABSTRACT FROM AUTHOR]

The energy demand in the modern power system is increasing day by day. Thus integration of microgrid with the conventional grid can fulfill the high power demand but it can cause many changes in the power system. In this paper, a real valued Damodar Valley Corporation (DVC) grid connected microgrid system is formed with the help of Power System Analysis Toolbox (PSAT) software and analyzed the performance by Continuous Power Flow (CPF) method. A three phase short circuit fault is also introduced in the main grid and voltage profile is observed. It is also observed that the voltage profile of the faulty system is improved when a microgrid is connected with that main DVC grid system. [ABSTRACT FROM AUTHOR]

We study the particle trajectories in the recently proposed five dimensional warped (generalized) Ellis–Bronnikov spacetime (5D-WGEB) (which does not require exotic matter) as well as it's four dimensional counterpart (4D-GEB) in detail and conduct a comparative study. Analytical approach provides conditions which determines three types of trajectories (trapped, returning and crossing) for both 4D and 5D spacetimes. Notably in 5D geometry existence of trapped trajectories become highly sensitive to the initial conditions. We have solved the timelike geodesic equations numerically and presented the trajectories graphically along with corresponding geodesic potentials. We thus distinguished the roles of the so-called wormhole parameter and the warping factor regarding their effects on the trajectories and embedding as such. Interestingly, the 5D-WGEB model shows the localization of massive particles around the location of the brane for growing warp factor and runaway trajectories for decaying warp factor. [ABSTRACT FROM AUTHOR]

To interact with its environment, a robot working in 3D space needs to organise its visual input in terms of objects or their perceptual precursors, proto-objects. Among other visual cues, depth is a submodality used to direct attention to visual features and objects. Current depth-based proto-object attention models have been implemented for standard RGB-D cameras that produce synchronous frames. In contrast, event cameras are neuromorphic sensors that loosely mimic the function of the human retina by asynchronously encoding per-pixel brightness changes at very high temporal resolution, thereby providing advantages like high dynamic range, efficiency (thanks to their high degree of signal compression), and low latency. We propose a bio-inspired bottom-up attention model that exploits event-driven sensing to generate depth-based saliency maps that allow a robot to interact with complex visual input. We use event-cameras mounted in the eyes of the iCub humanoid robot to directly extract edge, disparity and motion information. Real-world experiments demonstrate that our system robustly selects salient objects near the robot in the presence of clutter and dynamic scene changes, for the benefit of downstream applications like object segmentation, tracking and robot interaction with external objects. [ABSTRACT FROM AUTHOR]

Introduction: Influenza virus has been associated with cases of Parkinsonism, yet a direct relationship has not been confirmed in the literature. Different mechanisms of post-infectious Parkinsonism have been proposed including inflammatory, oxidative stress, and autoimmune. We report a first to our knowledge case of pediatric autoimmune Parkinsonism with autoantibodies to dopamine D2L receptor (anti-DRD2L antibodies), who underwent deep brain stimulation (DBS) of bilateral globus pallidi (GPi). Case report: A 13-year-old girl presented with Parkinsonism features after a severe case of influenza A. She underwent extensive work-up and was found to have elevated titers for anti-DRD2L antibodies. Patient was initially treated with IVIG and plasmapheresis with mild improvement, but her condition continued to worsen. She was responsive to levodopa; however, she developed severe dyskinesia. Patient underwent DBS implantation resulting in partial improvement in bradykinesia, tremors, and dyskinesia. Conclusion: This case is meant to raise awareness of a rare potential autoimmune complication after influenza virus and to share the experience and outcome using DBS to palliate some of the symptoms. [ABSTRACT FROM AUTHOR]

In the present investigation, machining performance of Ti6Al4V is studied under dry environment, pressurized air supply and distilled water based Minimum Quantity Lubrication (MQL). Machining (turning) performance is assessed in purview of cutting force (tangential component) magnitude, tool-tip temperature, width of tool flank wear progression, morphology of evolved chips and severity of vibrations at varied cutting speeds as well as cooling media. Characteristic features of spatial temperature distribution profile (at the vicinity of tool-tip) as influenced by varied cooling media are studied with the help of thermographs of the cutting zone. Mechanisms of cutting tool wear are studied as well. It is experienced that amongst three cutting environments tested, application of water-MQL is beneficial for machining of Ti6Al4V at low cutting speed. Severity of vibrations gets 50.39% reduced during machining under water-MQL than dry condition. Consequently, as compared to dry machining, water-MQL causes 79% reduced tool flank wear and 82% reduced crater wear at low cutting speed. Under water-MQL, reduced tool-tip temperature (66% reduced than dry condition) suppresses severity of tool wear. In comparison with high cutting speed, performance of water-MQL is found much better at low cutting speed. 'Unaffected zones' are identified at the worn-out tool rake face under water-MQL. High amplitude of vibration (maximum absolute mean value) causes low chip-segmentation ratio. On the contrary, chip reduction coefficient gets truncated with decrement in vibration amplitude. Vibration amplitude has positive influence on degree of chip-curl. [ABSTRACT FROM AUTHOR]

Ellis–Bronnikov (EB) wormholes require violation of null energy conditions at the 'throat'. This problem was cured by a simple modification of the 'shape function', which introduces a new parameter m ≥ 2 ( m = 2 corresponds to the EB model). This leads to a generalised (GEB) version. In this work, we consider a model where the GEB wormhole geometry is embedded in a five dimensional warped background. We studied the status of all the energy conditions in detail for both EB and GEB embedding. We present our results analytically (wherever possible) and graphically. Remarkably, the presence of decaying warp factor leads to satisfaction of weak energy conditions even for the EB geometry, while the status of all the other energy conditions are improved compared to the four dimensional scenario. Besides inventing a new way to avoid the presence of exotic matter, in order to form a wormhole passage, our work reveals yet another advantage of having a warped extra dimension. [ABSTRACT FROM AUTHOR]

Electrically conducting flexible polymeric nanocomposite has been fabricated through wet mixing method where conducting inclusion was acoustically exfoliated pristine graphene nanosheets. Colloidal graphene is the key component here which has been prepared by acoustic cavitation in the presence of macromolecular dispersion. The significance of the method is their green preparation strategy without using any chemical reducing agents and long self-life without drastic sedimentation rate. Thermoplastic poly(ethylene-co-methyl acrylate) was chosen as flexible phase where graphene sheets were distributed to make spatial conducting network architecture. The prepared nanocomposites showed 0.259 S/cm DC electrical conductivity and frequency-independent electroconducting character in higher concentration. The electromagnetic interference shielding effectiveness of the nanocomposites was around 30 dB in ~ 1.0 mm thickness in X-band (8.2–12.4 GHz) frequency range without affecting its mechanical toughness and flexibility. Thus, such pristine graphene-based thermoplastic matrix could be a desirable replacement of metallic shielding materials on the ground of flexible, conducting, lightweight characteristics. [ABSTRACT FROM AUTHOR]

The role of the microgrid to meet up the localized power demand is of immense importance considering the growing power demand as well as grid inadequacy in Indian power scenario. Apart from meeting localized power demand with various distributed generating sources microgrid can render support to the adjacent main grid or similar localized grid as when needed. This paper presents the techniques for identifying placement sites for Phasor Measurement Units (PMUs) in a microgrid system based on complete observability of the system. The main objective of optimal placement of PMU problem is to determine a minimal set of PMUs such that the whole system is observable. This study has been done on a 14 bus test model with the help of PSAT. [ABSTRACT FROM AUTHOR]

Purpose: Infants with brain injury are susceptible to developmental delays. Survivors of neonatal seizures are at risk for developmental delay, epilepsy, and further neurological comorbidities. Despite advances in neonatal critical care, the prevalence of adverse long-term outcomes and seizure recurrence remains unchanged. Our goal is to determine if early treatment of neonatal seizures with phenobarbital or levetiracetam is associated with worse neurodevelopmental outcomes in brain-injured infants. Methods: We conducted a retrospective cohort study of 119 infants admitted between 2013 and 2017 who were at risk for developmental delay and assessed in our clinic. We compared brain injury infants with neonatal seizures to brain injury infants without neonatal seizures using Bayley scores (BSID III) at 9–14 months gestational age. A comparison of Bayley scores between those exposed to phenobarbital and levetiracetam was conducted. Results: Twenty-two children with neonatal seizures scored lower than 53 children without seizures in all domains with significant values in composite scores for cognitive function (p = 0.003) and language (p = 0.031). We found no difference in scores at 9–14 months between infants exposed to phenobarbital versus levetiracetam. Conclusions: Our results suggest that in infants with brain injury, the occurrence of neonatal seizures has an adverse effect on neurodevelopmental outcomes. The choice of antiseizure medication may not play a significant role in their outcomes. [ABSTRACT FROM AUTHOR]

In this article, we propose a new approach to segmentation-free word spotting that is based on the combination of three different contributions. Firstly, inspired by the success of bounding box proposal algorithms in object recognition, we propose a scheme to generate a set of word-independent text box proposals. For that, we generate a set of atomic bounding boxes based on simple connected component analysis that are combined using a set of spatial constraints in order to generate the final set of text box proposals. Secondly, an attribute representation based on the Pyramidal Histogram of Characters (PHOC) is encoded in an integral image and used to efficiently evaluate text box proposals for retrieval. Thirdly, we also propose an indexing scheme for fast retrieval based on character n-grams. For the generation of the index a similar attribute space based on a Pyramidal Histogram of Character N-grams (PHON) is used. All attribute models are learned using linear SVMs over the Fisher Vector representation of the word images along with the PHOC or PHON labels of the corresponding words. We show the performance of the proposed approach in both tasks of query-by-string and query-by-example in standard single- and multi-writer data sets, reporting state-of-the-art results. [ABSTRACT FROM AUTHOR]

Introduction: Therapeutic hypothermia for the treatment of moderate to severe neonatal hypoxic ischemic encephalopathy has been shown to reduce death and disability, but the effects on seizures after discharge from the Neonatal ICU are not known. Methods: A retrospective cohort study was conducted involving 56 neonates admitted to the Neonatal ICU at Children's Hospital of Orange County, CA from January 1, 2007 to September 1, 2013 with hypoxic ischemic encephalopathy who met criteria for selective brain cooling. Fifteen patients received supportive care. Forty-one patients received cooling, of whom 25 were included for analysis. Sixteen patients from the hypothermia group and 12 from the no hypothermia group developed clinical seizures while inpatient. Up to 6 months, four patients (16%) had continued seizures in the therapeutic hypothermia group compared to eight (53%) patients who did not receive hypothermia. Discussion: Our study shows an association between therapeutic hypothermia and reduced seizures after discharge from the neonatal intensive care unit. The short duration of follow-up, 6 months, is a limitation of this study. Another limitation is its observational nature, where reasons for treatment selection and exclusions are unmeasurable confounding factors. Further studies are needed to determine long-term effects. [ABSTRACT FROM AUTHOR]

This work focuses on an unexplored aspect of non-symmetric geometry where only the off-diagonal metric components along the extra dimension, in a 5-dimensional spacetime, are non-symmetric. We show that the energy densities of the stationary non-symmetric models are similar to that of brane models thereby mimicking the thick-brane scenario. We find that the massive test particles are confined near the location of the brane for both growing and decaying warp factors. This feature is unique to the non-symmetric nature of our model. We have also studied the dynamical models where standard 4D FLRW brane is embedded. Our analysis shows that the non-symmetric terms deconfine energy density at the early universe while automatically confine at late times. [ABSTRACT FROM AUTHOR]

Energy momentum tensor of a conformally coupled quantum scalar field in five dimensional warped cosmological spacetimes is studied. We look at situations where the four dimensional part represents a cosmological thick brane and the scale of the extra dimension is time dependent. Renormalization of the components of the energy momentum tensor is achieved using adiabatic regularization method. The resulting energy and pressure densities explicitly show the effects of warping and the dynamic extra dimension on the created matter. We discussed how the created matter may accumulate to form thick branes along the extra dimension. [ABSTRACT FROM AUTHOR]