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International audience; The stochastic estimation of coherency is perceived, in some studies, to be significantly influenced by the time window length under consideration. For the engineering purposes, usually, coherency is estimated from the strong motion, i.e., the shear (S-) wave segment of the recorded time series. However, the identification of a purely S-wave dominated window could be challenging in case of complex wave mixing on the seismograms. Moreover, there has been relatively little research on how much variation, in reality, is introduced in the coherency estimates owing to the choice of signal length. Therefore, the debate about the procedure for selecting a representative time window has remained inconclusive: different authors keep their different practices. The current article is an effort to shed light on the sensitivity of the coherency estimates to the choice of various time windows. The research draws on the dataset gathered from a dense seismic-array deployed at the small size, shallow alluvial valley of Koutavos-Argostoli, situated in Cephalonia Island, Greece. The lagged coherency over interstation distance ranges from 5 to 80 m has been estimated from a set of 46 earthquakes having magnitude 2–5 and epicentral distance 3–200 km, considering different lengths of time windows. The findings revealed that the statistics of coherency estimates derived from many events is only weakly sensitive to the selection of time window lengths provided that the segments include the same energetic pulse.

Purpose/Objective(s) Radiation therapy requires immobilization hardware that may produce significant anxiety for a patient under treatment, particularly when covering the face. In cases where such anxiety is treatment limiting, 3D printing can provide for a better tolerated custom immobilization. The technical hurdles, fidelity of positioning, and clinical outcomes are reviewed for the treatment of oropharyngeal cancer in a patient who was unable to tolerate traditional mask-based immobilization. Materials/Methods A 3D printer was used to create a custom immobilization cradle for the treatment of squamous cell carcinoma of the oropharynx. This was used in the treatment of a patient who was unable to be simulated despite nine separate attempts, using a variety of open-faced immobilization techniques, anxiolytics, and coaching. Operative management was not feasible due to the patient's habitus and comorbidities. Despite acknowledging the severity of the situation, the patient could not complete simulation. Thus, after he was confirmed to still have locoregionally limited disease, we proposed creation of a 3D-printed cradle for the back of his head and neck, based on CT imaging without immobilization. Three separate attempts were made to complete the printing of the cradle. Major issues stemmed from the need to find a set of support structures that would allow for the proper printing of the area supporting the ears, as well as the back of the head. Ultimately, a dense array of column supports was successful, but still required buttressing of the columns with tape at several points during the print. In total, 664g of polylactic acid filament was used, as well as 525g of polyvinyl alcohol, a water soluble support material. Total print time was just under 78 hours for the final successful print. Results The patient was able to tolerate simulation and the full course of fractionated chemoradiotherapy. The cradle provided for a setup requiring mean absolute shift of 0.35 mm in the anterior-posterior direction, 0.17 cm in the cranio-caudal direction, and 0.36 cm in the lateral direction, and a couch kick of 1.28 degrees to bring the patient into alignment on final imaging. The patient is currently in stable condition and following up with both medical oncology and radiation oncology at regular intervals. Imaging and laryngoscopy, conducted at multiple time points following completion, shows him to have no evidence of disease, now at 10 months. Conclusion The full uses of 3D printing are still developing, as evidenced by the difficulty of creating a workable print, both in terms of prototyping and the time needed to create a print. The impact of 3D printing within the context of radiation oncology, as well as in other specialties, will undoubtedly continue to increase the variety of viable treatment options available to patients as the technology improves.

The spatial variation of the earthquake ground motion over short distances can significantly affect the dynamic response of large and extended engineered structures, especially on sites with inhomogeneity in surface geology and geometry. In current practices, such variation is taken into account in terms of coherency, a function of frequency and distance, established on an essentially empirical basis and difficult to extrapolate at different sites. Hence, a better understanding of its physical significance and its relationship with the underlying ground structure is indispensable. A two-dimensional dense array, deployed at the small and shallow Koutavos-Argostoli valley in Cephalonia, Greece, provided an abundance of data to study the stochastic characteristics of seismic ground motions over very short distances. A set of 46 magnitude 2-5 events at epicentral distances 0-200 km has been selected for the analysis. The lagged coherency of the S-wave dominating seismogram was computed for each station-pair within the array and was averaged over various distance intervals for the whole data set. The results indicate a lack of a clear dependence of the average coherency on the magnitude, back azimuth or site-to-source distance of the event. The most striking result concerns the influence of the site geometry: the coherency is systematically lower for the pairs aligned perpendicular to the axis of the valley (2D) compared to those aligned in the parallel direction. This finding is consistent with the dominance of valley-edge generated surface waves propagating from one edge to the other. The averaged coherency estimates are only weakly represented by the existing parametric models, indicating its strong site dependent nature.

In this paper, we would like to report on a prototype of dense array concentrator photovoltaic (DACPV) system including the practical implementation and economic assessment. The newly proposed system consists of primary concentrator in the form of non-imaging dish concentrator and secondary concentrator as an array of dielectric filled crossed compound parabolic concentrators coupled to multi-junction solar cells. Optical and electrical simulations have been carried out to analyze the overall performance of the prototype for difference rim angles and tracking accuracies. A special method has been developed to plot the I-V and P-V curves of the prototype on-site without using commercial I-V tracer. The average cell efficiencies for all basic modules in the DACPV receiver were measured onsite in the range from 35.0% to 36.1%, which is very close to the laboratory test result conducted by Spectrolab at 38.5%. On the other hand, the system efficiency of our prototype system was measured only in the range between 16.1% and 17.4% at DNI ranging from 740 to 801 W/m2. For economic analysis, the cost per watt of current prototype has been determined as USD 5.8/W based on the price of only building one unit. The techno-economic of DACPV system can be further improved in the future by increasing solar concentrator ratio more than 1600 suns and reducing the optical losses incurred by the secondary concentrator.

Responses of an asymmetrical base-isolated building during the passage of Typhoon Roke 2011, Typhoon Guchol 2012 and a bomb cyclone strong-wind event on April 3, 2012 were investigated in this paper. Wind-induced accelerations of the building were recorded by dense array permanent monitoring system and analyzed in detailed by spectra analysis, time-frequency wavelet analysis and system identification. Results of analysis revealed that wind-induced responses of the buildings were dominated by the first mode which is the fundamental flexural mode coupled with torsion of the upper stories. Building responses demonstrated non-linear characteristics of natural frequencies, damping ratio and mode-shapes. Natural frequencies of fundamental modes decreased with the increase of acceleration amplitude, with the maximum reduction of 8–10% of natural frequencies observed during the peak wind speed. Damping estimates of the fundamental modes increased with the increase of accelerations, while characteristics of mode-shapes were also found to be dependent on the wind speed. Further analysis revealed that non-linear characteristics of building responses are related to isolator deformations caused by wind-induced static force.

Mesoscale in situ meteorological observations are essential for better understanding and forecasting the weather and climate and to aid in decision-making by a myriad of stakeholder communities. They include, for example, state environmental and emergency management agencies, the commercial sector, media, agriculture, and the general public. Over the last three decades, a number of mesoscale weather and climate observation networks have become operational. These networks are known as mesonets. Most are operated by universities and receive different levels of funding. It is important to communicate the current status and critical roles the mesonets play. Most mesonets collect standard meteorological data and in many cases ancillary near-surface data within both soil and water bodies. Observations are made by a relatively spatially dense array of stations, mostly at subhourly time scales. Data are relayed via various means of communication to mesonet offices, with derived products typically distributed in tabular, graph, and map formats in near–real time via the World Wide Web. Observed data and detailed metadata are also carefully archived. To ensure the highest-quality data, mesonets conduct regular testing and calibration of instruments and field technicians make site visits based on “maintenance tickets” and prescheduled frequencies. Most mesonets have developed close partnerships with a variety of local, state, and federal-level entities. The overall goal is to continue to maintain these networks for high-quality meteorological and climatological data collection, distribution, and decision-support tool development for the public good, education, and research.

Electroencephalography (EEG) spikes and focal epileptic seizures are generated in circumscribed cerebral networks that have been insufficiently described. For precise time and spatial domain network characterization, we applied in patients with focal epilepsy dense array 256-channel EEG recordings with causal connectivity estimation by using time-resolved partial directed coherence and 3T-magnetic resonance imaging-derived cortical and thalamus integrity reconstruction. Before spike generation, significant theta and alpha bands driven information flows alterations were noted from both temporal and frontal lobes to the thalamus and from the thalamus to the frontal lobe. Medial dorsal and ventral anterior nuclei of the thalamus were delimited as possible pacemakers. Markedly reduced thalamic volumes and impaired cortical integrity in widespread areas predicted the altered information flows. Our data reveal distinct patterns of connectivity involving the thalamus and frontal cortex that are both directly and causally involved in spike generation. These structures might play an essential role in epileptogenesis and could be targeted in future therapeutic approaches.

To overcome self-weight induced optical misalignment has always been a great challenge in optimizing electrical performance of dense-array concentrator photovoltaic (CPV) system. In this article, the correction of elevation angle in the sun-tracking algorithm of non-imaging dish concentrator is proposed for recovering the deviated solar flux distribution caused by the structural deflection induced optical misalignment. Numerical simulation via ray-tracing technique has been employed to analyze the concentrated flux distribution and the simulated result has shown that the proposed method is proficient to restore the deviated solar flux distribution back to the center of the receiver for any elevation angle in the dense-array CPV system.

The first step in the controlled storage of lengthy DNA molecules is to keep DNA molecules separated while integrated in micrometer-sized space. Herein, we present hybrid Monte Carlo simulations of a histone-complexed DNA (hcDNA) molecule confined in a dense array of nanoposts. Depending on the nanopost dimension, a single, 8.7 kilobase pair hcDNA molecule was either localized and elongated in a single inter-post space surrounded by four nanoposts or spread over several inter-post spaces through passages between two neighboring nanoposts. The conformational change of a hcDNA molecule is interpreted in terms of competitive effects of confinements in the inter-post and passage spaces. We propose that, by elaborately designing nanopost arrays, the competitive confinement effects can be adjusted such that each hcDNA molecule is localized in a single inter-post space, and thereby multiple hcDNA molecules can be physically separated from each other while stored together in the nanopost array.

Organoids are three dimensional structures composed of multiple cell types that are capable of recapitulating tissue architecture and functions of organs in vivo. Formation of organoids has opened up different avenues of basic and translational research. In recent years, testicular organoids have garnered interest in the field of male reproductive biology. Testicular organoids allow for the study of cell-cell interactions, tissue development, and the germ cell niche microenvironment and facilitate high throughput drug and toxicity screening. A method is needed to reliably and reproducibly generate testicular organoids with testis specific tissue architecture. The microwell culture system contains a dense array of pyramid-shaped microwells. Testicular cells derived from pre-pubertal testes are centrifuged into these microwells and cultured to generate testicular organoids with testis-specific tissue architecture and cell associations. Thousands of homogeneous organoids can be generated via this process. The protocol reported here will be of broad interest to researchers studying male reproduction.

Electric source imaging (ESI) based on dense array electroencephalography (EEG) is a non-invasive technique for source localization of epileptic activity. However, the diagnostic accuracy of this tool is still debatable. In this study we aimed to investigate the source of epileptiform discharges in a group of epilepsy patients. For this, 20 patients (24.4 ± 8.0 years, 10 males) with drug-resistant focal epilepsy were included. All patients underwent 256-channel EEG recordings and were imaged on a 3T MRI scanner according to a predefined protocol. For spatio-temporal source reconstruction, LORETA (low resolution brain electromagnetic tomography) solution was applied to interictal averaged spikes. Electric sources of epileptiform discharges were detected in all 20 patients. In 18 (90%) patients source localization was concordant with patients’ seizure semiology. The most frequent source was identified in the temporal lobe. Dense array EEG is an accurate modality for localization of epileptogenic brain areas in the pre-surgical evaluation of drug-resistant epilepsy patients.

Implementation of the neuromorphic computing requires a hardware network system to mimic the functionality of biological neural systems. The development of digital nonvolatile resistive memory in a large and dense array is maturing and it provides a tremendous commercial opportunity to enable the hardware accelerator development. In this work, we have designed the RRAM device structures and developed the backend-of-line (BEOL) CMOS integration processes to fabricate the memory chips of 64Kb array, and achieved a high fabrication yield $\gt99.79$% with programmable characteristics to meet the requirements of different application algorisms. The chips as the building block of artificial neuromorphic network have low writing energy, fast writing speed, high endurance and retention. Most importantly, we demonstrated the remarkable capabilities chips to facilitate neuromorphic computing.

In this contribution, we study the effects arising when using a metamaterial surface featuring a dense array of superradiant emitters as cavities for experiments in the ultrastrong coupling regime. We show that an increasing cavity loss does not always lead to the expected transition to the weakly coupled Purcell regime but more that it is still possible to observe polaritons as a feature of the strong coupling between the metaatoms and the intersubband transition.

Schizophrenia affects approximately 10% of the world's population. Early detection of schizophrenia may significantly delay its progression. Although sensory gating deficits are reported in schizophrenia, it remains challenging how sensory gating deficits can be used with other metrics for risk detection and early diagnosis.Using EEG, the authors examined effects of sensory gating on the performance of 136 participants in a P50 sensory gating task, including patients with first-episode schizophrenia (FESZ), ultra-high risk (UHR) individuals, high-risk (HR) individuals, and age- and sex-matched healthy controls (HCs). The authors also explored the differences among all groups using clinical assessments and cognitive tests.Compared with HCs, HR, UHR and FESZ groups showed significant P50 suppression impairment. Furthermore, EEG source localization analyses identified successively stronger activation in prefrontal and anterior temporal regions in the HR, UHR and FESZ groups than in the HC group. Moreover, brain connectivity (HC HR UHR FESZ) in the gamma band of P50 components was increasingly enhanced in accordance with the level of psychosis risks.These findings suggest that EEG source imaging techniques, brain network dynamics, and behavioral tests, can help clearly distinguish different stages of schizophrenia, and may assist in the early diagnosis of schizophrenia.

Damage characterization often requires direct sensing due to the localization of the anomalous behavior near the cracks. Direct sensing, however, is expensive because of the need to deploy a dense array of individual sensors. Sensing sheets based on Large Area Electronics (LAE) and Integrated Circuits (ICs) are a novel solution to this problem. Such sensing sheets could span several square meters, with a dense array of strain sensors embedded on a polyimide substrate along with the relevant electronics allowing for direct sensing while keeping the costs low. Current studies on LAE based sensing sheets are limited to laboratory experiments. This paper explores the question of suitability of the sensing sheets as a viable option for real-life SHM based on LAE and ICs. Results of laboratory experiments on an aluminum beam are provided to demonstrate the performance of sensing sheets in ideal conditions. Then, the sensing sheets are employed on a pedestrian bridge already equipped with fiber-optic sensors. The strain measurements from the sensing sheets and the fiber-optic sensors are compared and sources of differences are discussed.

The focus of this thesis is the detection and localization of weak sources on the San Jacinto Fault Zone. The primary targets of interest are sources in the shallow crust, with depth down to a few kilometers. For sources at these depths high frequency content and low energy are expected. Surface sources present on and around the array site are also studied in order to discriminate them from weak seismic sources at depth.We rely on a methodology based on array processing to detect and localize shallow and weak seismic events in the fault zone complex environment. We use Match field Processing on data recorded from a dense array of 1108 vertical component geophones in a 600m x 600m area on the Clark branch of the San Jacinto Fault. We first test the method on a set of chosen events at depth and at the surface. Source epicentral positions and associated apparent velocities are then inverted for surface and seismic sources for 26 days, with the intention of determining if shallow sources are present. Inverting only for these three parameters is less expensive in terms of computational cost and is suitable for a first approach. However, this first inversion leaves us unable to conclude on the presence of shallow sources. As the resolution at depth is insufficient when all three source coordinates are inverted with a classical homogeneous velocity model, we finally investigate strategies to improve resolution at depth without increasing computational cost., Cette thèse traite de la détection et de la localisation de sources autour de la faille de San Jacinto. Son but était de détecter des sources dans la croute superficielle, sur des profondeurs de l'ordre de quelques kilomètres. Ces sources ont une faible énergie et émettent principalement dans les hautes fréquences. Les sources à la surface autour et sur le réseau possèdent les mêmes caractéristiques et sont aussi étudiées afin de pouvoir les séparer des évènements en profondeur.Une méthode basée sur le traitement d'antenne, le Match Field Processing (MFP), est utilisée pour détecter et localiser de faibles évènements à faible profondeur et à la surface. Le MFP est appliqué a des données mesurées grâce a un réseau dense de capteurs une composante déployés sur une zone de 600mx600m sur la faille de San Jacinto. La méthode a d'abord été testée sur un ensemble d'évènements à la surface et en profondeur. Nous appliquons ensuite la technique sur 26 jours de données, afin de déterminer si des évènements sont présents en proche surface. Pour cela, seules la position en surface de la source et la vitesse apparente des ondes émises sont utilisés comme paramètres d'inversion. L'utilisation de ces trois paramètres permet de réaliser une première étude à moindre coût de calcul. Cependant cette première inversion ne permet pas de conclure sur la présence de sources en proche surface. L'information sur la position de la source en profondeur est nécessaire. Les résultats de localisations qui incluent la profondeur comme paramètre étant peu concluants lorsque le modèle classique de vitesse homogène est utilisé, nous étudions ensuite différentes stratégies pour améliorer la résolution en profondeur sans augmenter le coût de calcul.

The present study investigates how sexual dimorphism in the human mandible develops in three-dimensionally during adolescence. A cross-sectional sample of mandibular meshes of 268 males and 386 females, aged between 8.5 and 19.5 years of age, were derived from cone beam computed tomography and were analysed using geometric morphometric methods. Growth trajectories of the mandible in males and females were modelled separately using a recently developed non-linear kernel regression framework. Growth rate and direction at a dense array of points all over the mandibular surface were visualized within each group and compared between groups. We found that mandibular sexual dimorphism already exists at 9 years of age, but this is mostly in size not in shape. The differential growth rate and duration between the sexes during pubertal growth largely explained by adult sexual dimorphism: the growth direction in both males and females is similar but the male mandible changed more quickly and over a longer period than the female mandible, where the growth rate peaked and declined earlier. This results in increasing dimorphism in form, which is evident in both size and shape. The development of dimorphic features, concentrated in the chin and ramus, were further visualized. The dense morphometric approach provides detailed three-dimensional quantitative assessment of the development of sexual dimorphism of the mandible. ispartof: JOURNAL OF ANATOMY vol:234 issue:5 pages:1-9 ispartof: location:England status: Published online

Pervasive in Earth’ orbit, hypervelocity impact (HVI), caused by micrometeoroids and orbital debris (MMOD), poses an immense threat to the safety and integrity of spacecraft, leading to the failure and fragmentation of the entire spacecraft structures. Addressing such an issue, HVI-induced damage in space structures is localized using in-situ acoustic emission (AE). However, conventional AE localization techniques in the stiffened curved structures require either the knowledge of the direction dependent velocity profile or a dense array of sensors, due to the attenuation and anisotropic-like propagation of AE signals. In this work, a new approach of area localization is proposed to locate the HVI-induced acoustic source in large-scale anisotropic-like plates with a sparse array of sensors, and without knowing the direction dependent velocity profile in the plate. On this basis, the impact spot can be precisely located.

Surface electromyography (sEMG) allows to evaluate neurophysiological aspects of movements. The traditional muscle-specific sEMG approach requires considerable expertise to correctly position bipolar derivations over each muscle of interest. This reduces the availability of myoelectric imaging tools for non-professional users in everyday life conditions. High-density EMG (HDsEMG) consists of recording the sEMG via a dense array of electrodes that restricts the imaging surface to a narrow area, thus limiting usability. Here we demonstrate the usability and advantages of a medium-density sEMG (MDsEMG). We recorded the muscle activity of a subject performing repeated arm flexion and extension using both muscle-specific sEMG (4 derivations over the biceps and triceps) and MDsEMG (28 monopolar derivations, positioned around the arm circumference). Grand-average dynamic-time-warped amplitudes showed similar activation patterns for both modalities. However, MDsEMG allowed to extract maps reflecting the spatial activation of muscles at different movement phases (minimum and maximum acceleration). MDsEMG also proved superior in decoding the elbow angle and allowed to map the regions of maximum significance. MDsEMG is a viable alternative to muscle-specific and HD sEMG. It does not require expertise in electrode positioning and is able to cover large surfaces. It thus can pave the way to easier myoelectric imaging in everyday life and more effective rehabilitation treatments.

BackgroundSuction organs provide powerful yet dynamic attachments for many aquatic animals, including octopus, squid, remora, and clingfish. While the functional morphology of suction organs from some cephalopods and fishes has been investigated in detail, there are only few studies on such attachment devices in insects. Here we characterise the morphology and ultrastructure of the suction attachment organs of net-winged midge larvae (genusLiponeura; Diptera: Blephariceridae) – aquatic insects that live on rocks in rapid alpine waterways where flow speeds can reach 3 m s− 1– using scanning electron microscopy, confocal laser scanning microscopy, and X-ray computed micro-tomography (micro-CT). Furthermore, we study the function of these organs in vivo using interference reflection microscopy.ResultsWe identified structural adaptations important for the function of the suction attachment organs inL. cinerascensandL. cordata. First, a dense array of spine-like microtrichia covering each suction disc comes into contact with the substrate upon attachment, analogous to hairy structures on suction organs from octopus, clingfish, and remora fish. These spine-like microtrichia may contribute to the seal and provide increased shear force resistance in high-drag environments. Second, specialised rim microtrichia at the suction disc periphery were found to form a continuous ring in close contact and may serve as a seal on a variety of surfaces. Third, a V-shaped cut on the suction disc (“V-notch“) is actively opened via two cuticular apodemes inserting on its flanks. The apodemes are attached to dedicated V-notch opening muscles, thereby providing a unique detachment mechanism. The complex cuticular design of the suction organs, along with specialised muscles that attach to them, allows blepharicerid larvae to generate powerful attachments which can withstand strong hydrodynamic forces and quickly detach for locomotion.ConclusionThe suction organs fromLiponeuraare underwater attachment devices specialised for resisting extremely fast flows. Structural adaptations from these suction organs could translate into future bioinspired attachment systems that perform well on a wide range of surfaces.

International audience; We describe in this work an advanced microfluidic chip for the capture of bioanalyte on the surface of droplets arranged in a dense array. We show the procedure for generating, functionalizing, and arranging the droplets inside the device for capturing a specific bioanalyte. Then, we demonstrate the capacity of the array to capture analyte from a cross-flowing liquid, using a biotin/streptavidin model. The paper also proposes to use the droplets array, after integration with acoustic detection, as a regenerable detection interface for bioanalyte sensing. We model the arrangement of droplet in dense array and show that they present a larger effective capture surface and shorter capture distance than standard flat surface biosensor of the same footprint. As the droplets can be easily evacuated and replaced inside the device analysis chamber, the proposed biosensor would allow biointerface regeneration and chain measurement without dismounting the device.

The EEG source localization is an ill-posed problem. It involves estimation of the sources which outnumbers the number of measurements. For a given measurement at given time all sources are not active which makes the problem as sparse inversion problem. This paper presents a new approach for dense array EEG source localization. This paper aims at reducing the solution space to only most certain sources and thereby reducing the problem of ill-posedness. This employs a two-stage method where the first stage finds the most certain sources that are likely to produce the observed EEG by using a statistical measure of sources, the second stage solves the inverse problem by restricting the solution space to only most certain sources and their neighbors. This reduces the solution space for other source localization methods hence improvise their accuracy in localizing the active neurological sources in the brain which is the main goal. This method has been validated and applied to real 256 channel data and the results were analyzed., IEEE Transactions on Neural Systems & Rehabilitation Engineering, 2018

Rapid development in structural health monitoring systems has led to the invention of various sensing technologies. Nonetheless, difficulties in deploying and maintaining traditional wired sensors and managing vast amount of data collated from a dense array of wired sensors were fundamental drawbacks of using such systems. Wireless sensor networks (WSNs) were thus introduced to overcome the noted shortcomings. However, the energy required to power WSNs has become an important concern due to battery limitations. Energy harvesting technologies have been developed to extend the lifetime of WSNs by addressing the energy constraint problem. Recently, a new generation of WSNs based on self-powered sensors have become a reality by bridging the gap between the harvested energy and the energy required for sensing, computation, storage, and communication. Self-powered sensors are increasingly being used and establishing themselves as promising solutions to conventional WSNs in civil infrastructure. This review paper summarizes the applications of self-powered sensors in civil infrastructure during the last decade. First, a general introduction to self-powered sensing and its significance in civil engineering are presented. Thereafter, various self-powered sensors currently used in civil engineering arena are reviewed. Finally, the advantages of deploying these sensors are presented, and future research trends for their innovative use are highlighted.

Rendering objects invisible to impinging acoustic waves (i.e., acoustic cloaking), is a mature topic in the acoustic community and has diverse applications. Nevertheless, existing approaches and physical demonstrations still exhibit a large range of assumptions and limitations. Passive approaches, which surround the scattering object with a suitable (meta-)material, are usually only effective in a narrow frequency-band and cannot adapt to changing incident fields. Active approaches, which rely on the emission of a secondary wavefield that destructively interferes with the scattered field, have the potential to respond dynamically and be broad band. However, without knowledge of the primary or scattered field, the signals for the secondary sources need to be estimated from wavefield measurements in real-time. To our knowledge, this was never demonstrated beyond 1D acoustic experiments to achieve global broadband control of forward- and backscattered waves. Here, we present experimental results of active, broadband 2D acoustic cloaking without any assumptions of the primary or scattered wavefields. Using a low-latency control system and a dense array of control microphones, the signals for 20 control sources surrounding the scatterer are estimated and applied in real-time to achieve fully deterministic, global acoustic cloaking.

Interplay between preferential sputtering of multicomponent solids and topology of sputtered surface has been studied using a sequence of IVB tellurides PbTe, SnTe, and GeTe. The first experimental observation of the impact of near-non-preferential sputtering on the surface topology of multicomponent materials was made. In the example of SnTe, it was found that a sputtered surface resulting from its near-non-preferential sputtering is always covered with a dense array of cones of nanometer range of height. This observation opens the possibility for the simple method of formation of dense arrays of conical structures on solid surfaces by ordinary ion beam sputtering. Our experimental results show that to achieve this, a multicomponent composition, constituents of which are sputtered near-non-preferentially, has to be created.

A dense array of surfactant-stabilized water droplets (20 μm in diameter) floating on the surface of fluorinated oil was prepared. More than 30000 droplets were planarly arrayed in an 8 mm squared area using the “droplet guide”, an assembly of tubular wells located on the top wall of the fluidic channel. Parallel measurement of the melting temperatures of digitally partitioned KRAS DNAs hybridized with molecular beacons was demonstrated using the array of floating droplets.

III–V multi-junction solar cells are promising devices for photovoltaic applications under very high concentration levels of sunlight. Shadowing losses of the front side metallisation and ohmic resistance losses in the metal grid limit the practical cell size typically to around 1 cm2 at 1000 suns. The use of a full back-contact architecture, similar to the metal-wrap-through (MWT) technology known in silicon photovoltaics, can help to overcome this limitation. Furthermore, positioning both the positive and negative contact pads on the rear side of concentrator solar cells opens the possibility for efficient packaging solutions and the realisation of dense array receivers with low metal shadowing. The MWT technology addresses conventional concentrating photovoltaics as well as combined conventional concentrating photovoltaic-thermal applications and offers specific advantages for large-area devices at high intensities. This work presents the first experimental results for MWT architectures applied to III–V tandem solar cells and discusses specific challenges. An efficiency of 28.3% at 176 suns and 27.2% at 800 suns has been measured for the best MWT Ga0.51In0.49P/Al0.03Ga0.97As tandem solar cells. Copyright © 2016 John Wiley & Sons, Ltd.

We present a novel storage manager for multi-dimensional arrays that arise in scientific applications, which is part of a larger scientific data management system called TileDB. In contrast to existing solutions, TileDB is optimized for both dense and sparse arrays. Its key idea is to organize array elements into ordered collections called fragments. Each fragment is dense or sparse, and groups contiguous array elements into data tiles of fixed capacity. The organization into fragments turns random writes into sequential writes, and, coupled with a novel read algorithm, leads to very efficient reads. TileDB enables parallelization via multi-threading and multi-processing, offering thread-/process-safety and atomicity via lightweight locking. We show that TileDB delivers comparable performance to the HDF5 dense array storage manager, while providing much faster random writes. We also show that TileDB offers substantially faster reads and writes than the SciDB array database system with both dense and sparse arrays. Finally, we demonstrate that TileDB is considerably faster than adaptations of the Vertica relational column-store for dense array storage management, and at least as fast for the case of sparse arrays.

This paper presents a comparison of field data processing methods used to evaluate topographic effects. A data set of 52 weak motion events recorded using a dense array of seismometers located on steep, complex topography is analyzed. Both time domain and frequency domain analysis methods are evaluated for effectiveness at resolving the amplitude and frequency range associated with topographic effects. Results from this study indicate the median reference method (MRM) provides a more stable estimate of the frequency range and expected amplification value than the standard spectral ratio (SSR) or horizontal-to-vertical spectral ratio (HVSR) methods.

A concise route to a small family of exotic marine alkaloids known as the araiosamines has been developed, and their absolute configuration has been assigned. The dense array of functionality, high polarity, and rich stereochemistry coupled with equilibrating topologies present an unusual challenge for chemical synthesis and an opportunity for innovation. Key steps involve the use of a new reagent for guanidine installation, a remarkably selective C–H functionalization, and a surprisingly simple final step that intersects a presumed biosynthetic intermediate. Synthetic araiosamines were shown to exhibit potency against Gram-positive and -negative bacteria despite a contrary report of no activity.

Accurate and reliable damage characterization (i.e., damage detection, localization, and evaluation of extent) in civil structures and infrastructure is an important objective of structural health monitoring (SHM). Highly accurate and reliable characterization of damage at early stages requires continuous or quasi-continuous direct sensing of the critical parameters. Direct sensing requires deploying dense arrays of sensors, to enhance the probability that damage will result in signals that can be directly acquired by the sensors. However, coverage by dense arrays of sensors over the large areas that are of relevance represents an enormous challenge for current technologies. Large area electronics (LAE) is an emerging technology that can enable the formation of dense sensor arrays spanning large areas (several square meters) on flexible substrates. This paper explores the requirements and technology for a sensing sheet for SHM based on LAE and crystalline silicon CMOS integrated circuits (ICs). The sensing sheet contains a dense array of thin-film full-bridge resistive strain sensors, along with the electronics for strain readout, full-system self-powering, and communication. Research on several stages is presented for translating the sensing sheet to practical SHM applications. This includes experimental characterization of an individual sensor’s response when exposed to cracks in concrete and steel; theoretical and experimental performance evaluation of various geometrical parameters of the sensing sheet; and development of the electronics necessary for sensor readout, power management, and sensor-data communication. The concept of direct sensing has been experimentally validated, and the potential of a sensing sheet to provide direct sensing and successful damage characterization has been evaluated in the laboratory setting. A prototype of the sensing sheet has also been successfully developed and independently characterized in the laboratory, meeting the required specifications. Thus, a sensing sheet for SHM applications shows promise both in terms of practicality and effectiveness.

Ultrahigh-resolution 3D (UHR3D) seismic systems employing a dense array of short streamers represent a significant advancement in the field of marine seismic data acquisition and are an appropriate choice for many near-surface survey applications. Data comparisons between conventional 3D, reprocessed 3D, high-resolution 2D, and UHR3D seismic data illustrate the benefits of a UHR3D acquisition strategy. Results from a recent study of seeps imaged in the Gulf of Mexico (GoM) suggest that UHR3D data can serve as a comprehensive data source for some near-surface geophysical characterizations, satisfying many of the needs often addressed by integrating multiple separate types of survey data.

2nd Congress of the European Academy of Neurology, June, 2016, Copenhagen, Denmark, Neurology and Neurosurgery, Chisinau, Moldova, Municipal Clinical Emergency Hospital, Chisinau, Moldova

authoren We demonstrate that the selection of a limited number of single excitonic lines from a dense array of epitaxial quantum dots (QDs) can be realized spectrally via resonant energy transfer from a huge number of small QDs toward a limited set of large nano-islands through their excited levels. Optical and transmission electron microscopy studies support this mechanism. Theoretical modeling describes the architecture of quantum levels in the array of CdSe/ZnSe QDs, which enables such a spectral selection. Schematic of resonant energy transfer between QDs shown together with a plan-view TEM image of a QD array.

An important factor in mitigation of seismic hazard from induced seismicity is properly established seismic networks suitable for consistent identification of small‐to‐moderate events (magnitudes less than four). Here, we evaluate the performance of the newly established regional broadband seismic network in northeast British Columbia, Canada. The seismic network was designed for monitoring of induced seismicity due to oil and gas operations related to hydraulic fracturing and fluid injection in the region. We use regional and local earthquake catalogs for the period 1985–2015 to analyze magnitude of completeness and epicentral uncertainty. We also perform a theoretical assessment of minimum detectable magnitude across the study region based on analysis of ambient noise and simulated ground motions. From the frequency–magnitude distribution of the reported events in the regional earthquake catalog, the magnitude of completeness has decreased ∼1 magnitude unit from ∼3 in the periods 1985–2013 to ∼2 in the period 2013–2015 as a result of the establishment of new stations. The minimum detectable magnitude in the region is 1.6–2.6 based on the signal‐to‐noise ratio (SNR) of 10 and higher at four or more stations. By comparing the regional and dense array catalogs, we determine that the error in epicentral location in well‐constrained areas by seismic stations is below 3 km in both east–west and north–south directions. However, location uncertainties can be up to 10 km in the east–west direction in areas where the current regional network is sparse. The magnitude detection threshold in the Montney Play, where most of the current oil and gas activities are taking place, can be further reduced by up to 1 magnitude unit with the addition of four new stations.

This article is part of the themed collection: Nanoparticle Assembly: From Fundamentals to Applications, We present a theoretical study on the design of a supramolecular magnetoresponsive coating. The coating is formed by a relatively dense array of supracolloidal magnetic filaments grafted to a surface in a polymer brush-like arrangement. In order to determine and optimise the properties of the magnetic filament brush, we perform extensive computer simulations with a coarse-grained model that takes into account the correlations between the magnetic moments of the particles and the backbone crosslinks. We show that the self-assembly of magnetic beads from neighbouring filaments defines the equilibrium structural properties of the complete brush. In order to control this self-assembly, we highlight two external stimuli that can lead to significant effects: temperature of the system and an externally applied magnetic field. Our study reveals self-assembly scenarios inherently driven by the crosslinking and grafting constraints. Finally, we explain the mechanisms of structural changeovers in the magnetic filament brushes and confirm the possibility of controlling them by changing the temperature or the intensity of an external magnetic field., This research has been partially supported by the Austrian Research Fund (FWF): START-Projekt Y 627-N27. Authors are grateful to the Ural Federal University stimulating programme. S. S. K is supported by RFBR mol-a-ved 15-32-20549. E. V. N. acknowledges the support of President RF Grant No. MK-5216.2015.2. The authors are grateful to the Ministry of Education and Science of the Russian Federation (Project 3.12.2014/K) and EU-Project 642774 ETN-Colldense. J. J. C. and T. S. also acknowledge funding from a grant awarded by the Conselleria d'Innovació, Recerca i Turisme del Govern de les Illes Balears and the European Social Fund (ESF).

This study evaluated the localization precision of 256-channel dense array electroencephalographic source imaging (dESI) in comparison to conventional noninvasive tools. In addition, the study was designed to analyze the relationship between the 256-channel dESI source patterns and surgical outcome.Forty-three patients with temporal lobe epilepsy (TLE) who underwent one-stage resective surgeries were recruited in this study. We compared dESI with other noninvasive evaluation methods by comparing results with resections that eliminate or significantly reduced seizures according to sub-lobule and lobule criteria. Sensitivity and specificity of multiple evaluation methods were calculated. Kaplan-Meier analysis was performed to evaluate the relationship between source patterns and surgical outcome.dESI showed the best sensitivity (sub-lobule, 91.4%; lobule, 97.1%) and specificity (75%) for both sub-lobule and lobule criteria. The Kaplan-Meier survival analysis showed that cases with "single source" had better prognosis than with "multiple sources" (p0.05); cases of "sources within resection" showed better surgical prognosis than cases of "sources outside resection" (p0.05).In this study, 256-channel dESI provided a higher clinical yield than the other most broadly used noninvasive presurgical workup tools. dESI results with "single source" correlated strongly to good prognosis, while cases with "multiple sources" may cautiously be considered as candidates for one-stage resective surgeries. The resection of the irritative zone identified by interictal epileptiform discharges (IEDs) was related to good surgical prognosis in TLE.In the presurgical workup of TLE, the clinical yield of 256-channel dESI is high. Patterns of dESI results are related to surgical prognosis, and they can be instructive for presurgical planning. The resection of the irritative zone can be related to good surgical prognosis in TLE.

We show that simply by corroding Ni foam in an aqueous solution, it is possible to produce nanostructured surfaces. When Ni foam was corroded in water or an aqueous solution containing NaCl, a dense array of Ni(OH) 2 nanosheets was produced on the surface of the foam. When corroded in the presence of RuCl 3 , the nanostructured surface composed of Ni(OH) 2 nanosheets decorated with ultrasmall RuO 2 nanoparticles was obtained. At an applied voltage of 1.7 V, the combination of these two nanostructured surfaces yielded a water-splitting current density more than three times that obtained on the commercial Pt wire electrodes.

A finer direction-of-arrival (DOA) estimation result needs a large and dense array, it may, however, encounter the mutual coupling effect, which degrades the performance of DOA estimation. There is a new approach to mitigating this effect by using a nonuniform array to achieve DOA estimation. In this paper, we consider a priori DOA estimation, which is easily obtained from tracking results. The a priori DOA requires us to pay close attention to the high possibility of where the DOA will appear, then, a weight according to the prior probability distribution of DOA is added to each direction, which leads the sensing matrix of DOA estimation to be near low-rank. Thus, according to the low-rank matrix approximation theory, an optimal low-rank approximate matrix is obtained and an algorithm is proposed to select the elements of the original array according to right singular vectors of the approximate matrix. After that, the impacts of different weights are analyzed, and a mixed weight is presented which has flexibility for common use. Finally, a number of numerical simulations are carried out, and the results verify the effectiveness of the proposed methods.

openaire: EC/H2020/736937/EU//M-CUBE In this paper an approach for broadening of operational band in a dense array of dipole antennas by implementing passive split-loop resonators (SLRs) as decouplers is presented. Compared to the previous method, where three closely located active dipoles were decoupled by two passive dipole, the operational band is significantly improved from 0.5% to 1.6% at the same level of decoupling −8 dB for the cross-talk and inter-channel transmittance. To delineate, the presence of two SLRs results in birefringence of the resonant interaction of SLRs which creates two different eigenmodes for decoupling. As a result, a dual-resonant decoupled band is obtained. Alongside with analytical investigation, numerical and experimental investigations verify the veracity of our approach. Moreover, the possibility of decoupling by SLRs for arrays with more active dipoles is investigated numerically.

The Zhuxi ore deposit, located in Jiangxi province, South China, is the largest tungsten reserve in the world. To better understand the geological structure and distribution of orebodies, we conducted a high resolution three-dimensional P-wave velocity tomography of the uppermost 0.5 km beneath the Zhuxi ore deposit and adjacent area. Our velocity model was derived from 761,653 P-wave first arrivals from 998 control-source shots, recorded by a dense array. As the first 3D P-wave velocity structure of the Zhuxi ore deposit, our model agrees with local topographic and tectonic structures and shows depth-dependent velocity similar to laboratory measurements. The Carboniferous formations hosting the proven orebodies are imaged as high velocities. The high-velocity anomalies extend to a larger area beyond the proven orebodies, and the locations of high&ndash, low velocity boundaries are in accordance with the boundaries between the Neoproterozoic formation and the Carboniferous&ndash, Triassic formation. Seismic tomography reveals that high-velocity anomalies are closely related to the mineralized areas. Our results are helpful for further evaluating the total reserves and suggest that seismic tomography can be a useful tool for mineral exploration.

SCOPE: The neural efficiency hypothesis for lutein (L) and zeaxanthin (Z) suggests that higher levels of L+Z in the central nervous system (CNS) are predictive of stronger stimulus‐specific brain responses. Past research suggests that supplementing L+Z can improve neural processing speed and cognitive function across multiple domains, which supports this hypothesis. The purpose of this study is to determine the extent to which CNS L+Z levels predict brain responses using an attentionally taxing task. METHODS AND RESULTS: Macular pigment optical density (MPOD) is measured at baseline in 85 participants ranging in age from 18–92 years. Brain activation is measured using dense array electroencephalography. Stimuli evoking the signal include a grating array of vertical bars, oscillating at four driving frequencies. Significant stimulus‐specific interactions are detected between attend condition, location, and age (p < .002) for unattended image locations, and between age and location (p < .008) for attended locations. Although no differences are found across age by MPOD, this measure is found to be predictive of neural power at parafoveal bar locations (R² .080). CONCLUSION: CNS L+Z status is related to differences in brain activation in conditions designed to stress visual attention. These differences are strongest for older subjects.