This article investigates the politics of the image and montage in the literature and filmmaking as an experimentation with an ethical bet on research in Human Sciences. In the light of Walter ...Benjamin’s concept of montage, as well as DidiHuberman’s analysis of image as taking a position, it problematizes the insurmountable distance between the subject and the object, the fracture between form and content, ethics and aesthetics in research in the face of the intolerable of an ordinary world. The questions are presented through fragments that deal with the intertwining between body, memory, revolt, and creation, to emphasize the ethical bet of the montage not only as a balm for the body suffocated by the abject, but as the oxygen necessary for the multiplication of paths, senses, overcoming limits for the creation of resistance to the numbness of thought.
Prefabricated arrays with a limited number of electrodes offer an opportunity to hasten the diagnosis of seizures; however, their accuracy to detect seizures is unknown. We examined the utility of ...two limited-montage EEG setups for the detection of nonconvulsive seizures.
Thirty previously interpreted EEG segments with nonconvulsive seizures from 30 patients and 60 segments with background slowing or normal EEG from 60 patients were rendered in a bipolar "double banana" montage, a double distance "neonatal" montage, and a circumferential "hatband" montage. Experts reviewed 60 to 180 seconds long segments to determine whether seizures were present and if the EEG data provided were sufficient to make a decision on escalation of clinical care by ordering an additional EEG or prescribing anticonvulsants. The periodic patterns on the ictal-interictal continuum were specifically excluded for this analysis to keep the focus on definite electrographic seizures.
The sensitivities for seizure of the neonatal and hatband montages were 0.96 and 0.84, respectively, when compared with full montage EEG, whereas the specificities were 0.94 and 0.98, respectively. Appropriate escalation of care was suggested for 96% and 92% of occurrences of seizure patterns in neonatal and hatband montages, respectively. When compared with clinical EEG, the sensitivities of the neonatal and hatband montages for seizure diagnosis were 0.85 and 0.69, respectively.
Nonconvulsive seizures were detected with high accuracy using the limited electrode array configuration in the neonatal and hatband montages. The sensitivity of the neonatal montage EEG in detecting seizures was superior to that of a hatband montage. These findings suggest that in some patients with nonconvulsive seizures, limited-montage EEG may allow to differentiate ictal and slow patterns.
My paper will focus on some issues related to photographic image and its language, starting with the analysis of a photographic work created in 1937 by Bruno Munari for Almanacco letterario Bompiani ...of that year. The title of the insert is Udite, Udite!, it is a sixteenth note created by mounting quotations from Mussolini's speeches, photographs of the regime, and the portrait of the Duce inserted at the top of each page perforated as a “telescope", a graphic expedient that makes him 'physically' present. The description and commentary on Munari's work will be linked to issues, such as: the visual, cultural and psychological strategies of fascism, all focused on the image and 'corporeality' of Mussolini, also through photography; the 'resistance' action of Munari's photography and graphics given the author's awareness of the subtle power of visual communication, the ability of photography to strengthen opinions and positions and, as already experienced by Dadaism, “to turn poisons into an antidote"; the exploitation of the photographic medium, by propaganda and satire, in the exaltation of the physical, direct and multiple dimension to which the medium gives access. In the years of fascism, photography was, together with cinema, the regime's main communication tool, aimed mainly at enhancing the figure of Mussolini, his body, his resolute face. Munari, who since the Thirties has distinguished himself in graphics and advertising for his modern style, in Udite, Udite! shows a full awareness of the strategies of fascism, subjecting them to a skilful make-up operation. Using the same language of the regime, Munari bends it to a different meaning through the grammar of modernist collage and the enhancement of the conceptual component of the photographic image. He carries out an operation of ideological cosmetics, telling a different story, soliciting, without further verbal declarations, the critical sense of those who look and read.
The standardized EEG electrode array of the IFCN Seeck, Margitta; Koessler, Laurent; Bast, Thomas ...
Clinical neurophysiology,
October 2017, 2017-10-00, 20171001, 2017-10, Letnik:
128, Številka:
10
Journal Article
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•An array of 25 electrodes is recommended for standard EEGs with inferior temporal electrodes.•Due to thinner skulls (spatial aliasing), pediatric EEG requires as many scalp electrodes as in ...adults.•Arrays with higher electrode numbers (64–256 electrodes) allow source imaging at sublobar level.
Standardized EEG electrode positions are essential for both clinical applications and research. The aim of this guideline is to update and expand the unifying nomenclature and standardized positioning for EEG scalp electrodes. Electrode positions were based on 20% and 10% of standardized measurements from anatomical landmarks on the skull. However, standard recordings do not cover the anterior and basal temporal lobes, which is the most frequent source of epileptogenic activity. Here, we propose a basic array of 25 electrodes including the inferior temporal chain, which should be used for all standard clinical recordings. The nomenclature in the basic array is consistent with the 10–10-system. High-density scalp EEG arrays (64–256 electrodes) allow source imaging with even sub-lobar precision. This supplementary exam should be requested whenever necessary, e.g. search for epileptogenic activity in negative standard EEG or for presurgical evaluation. In the near future, nomenclature for high density electrodes arrays beyond the 10–10 system needs to be defined, to allow comparison and standardized recordings across centers. Contrary to the established belief that smaller heads needs less electrodes, in young children at least as many electrodes as in adults should be applied due to smaller skull thickness and the risk of spatial aliasing.
Objective. Human scalp electroencephalogram (EEG) is widely applied in cognitive neuroscience and clinical studies due to its non-invasiveness and ultra-high time resolution. However, the ...representativeness of the measured EEG potentials for the underneath neural activities is still a problem under debate. This study aims to investigate systematically how both reference montage and electrodes setup affect the accuracy of EEG potentials. Approach. First, the standard EEG potentials are generated by the forward calculation with a single dipole in the neural source space, for eleven channel numbers (10, 16, 21, 32, 64, 85, 96, 128, 129, 257, 335). Here, the reference is the ideal infinity implicitly determined by forward theory. Then, the standard EEG potentials are transformed to recordings with different references including five mono-polar references (Left earlobe, Fz, Pz, Oz, Cz), and three re-references (linked mastoids (LM), average reference (AR) and reference electrode standardization technique (REST)). Finally, the relative errors between the standard EEG potentials and the transformed ones are evaluated in terms of channel number, scalp regions, electrodes layout, dipole source position and orientation, as well as sensor noise and head model. Main results. Mono-polar reference recordings are usually of large distortions; thus, a re-reference after online mono-polar recording should be adopted in general to mitigate this effect. Among the three re-references, REST is generally superior to AR for all factors compared, and LM performs worst. REST is insensitive to head model perturbation. AR is subject to electrodes coverage and dipole orientation but no close relation with channel number. Significance. These results indicate that REST would be the first choice of re-reference and AR may be an alternative option for high level sensor noise case. Our findings may provide the helpful suggestions on how to obtain the EEG potentials as accurately as possible for cognitive neuroscientists and clinicians.
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•Nanocellulose-graphene-based materials used for supercapacitors are reviewed.•Design of different types of nanocellulose-graphene flexible supercapacitor electrode.•Broaden the ...application of nanocellulose-graphene in flexible energy storage devices.
With the increasing consumption of global fossil energy and environmental pollution, the development of green renewable energy and efficient energy storage technology become an urgent problem to solve. Supercapacitors have drawn a great interest for use in wearable electronic devices due to their portability and stable performance. The electrode is very important when preparing a high-performance flexible supercapacitor, which requires good electrochemical performance and flexibility. Graphene and nanocellulose are excellent flexible electrode material for supercapacitors, and nanocellulose is often used as a substrate material for electronic devices because of its good biodegradability, mechanical flexibility and chemical reactivity. In this work, the structure design and assembly method of the nanocellulose-graphene composite materials used for flexible supercapacitors are reviewed. The mechanical flexibility, specific capacitance, electrochemical performance, cyclic stability, renewability and biodegradability are taken into account, so as to evaluate the performance of the composite materials and to better assess the merits of this material with respect to real applications.
Objective. In electroencephalography (EEG) measurements, the signal of each recording electrode is contrasted with a reference electrode or a combination of electrodes. The estimation of a neutral ...reference is a long-standing issue in EEG data analysis, which has motivated the proposal of different re-referencing methods, among which linked-mastoid re-referencing (LMR), average re-referencing (AR) and reference electrode standardization technique (REST). In this study we quantitatively assessed the extent to which the use of a high-density montage and a realistic head model can impact on the optimal estimation of a neutral reference for EEG recordings. Approach. Using simulated recordings generated by projecting specific source activity over the sensors, we assessed to what extent AR, REST and LMR may distort the scalp topography. We examined the impact electrode coverage has on AR and REST, and how accurate the REST reconstruction is for realistic and less realistic (three-layer and single-layer spherical) head models, and with possible uncertainty in the electrode positions. We assessed LMR, AR and REST also in the presence of typical EEG artifacts that are mixed in the recordings. Finally, we applied them to real EEG data collected in a target detection experiment to corroborate our findings on simulated data. Main results. Both AR and REST have relatively low reconstruction errors compared to LMR, and that REST is less sensitive than AR and LMR to artifacts mixed in the EEG data. For both AR and REST, high electrode density yields low re-referencing reconstruction errors. A realistic head model is critical for REST, leading to a more accurate estimate of a neutral reference compared to spherical head models. With a low-density montage, REST shows a more reliable reconstruction than AR either with a realistic or a three-layer spherical head model. Conversely, with a high-density montage AR yields better results unless precise information on electrode positions is available. Significance. Our study is the first to quantitatively assess the performance of EEG re-referencing techniques in relation to the use of a high-density montage and a realistic head model. We hope our study will help researchers in the choice of the most effective re-referencing approach for their EEG studies.
Auxetic materials or structures, especially 3D cellular lattice architectures with negative Poisson's ratio (NPR) have attracted great attention due to their unprecedented mechanical behaviors and ...promising applications in recent years. Many 3D auxetic architected cellular materials have been manufactured and characterized with polymers and metals using additive manufacturing technology as well as some fibre reinforced polymers (FRP) composites via assembly method, however metal 3D printed auxetic structures with high-quality are rarely reported and FRP composites using assembly method contain a variety of defects which result in a knock-down effect on mechanical properties. Auxetic structures made from polymers are normally of low stiffness and strength and FRP composites are of low toughness and impact resistance, which causes limitations on their structural and functional applications. If rationally designed structures can be made from high-performance metal materials the specific stiffness and strength of which are much higher than polymers, their specific stiffness and strength can be significantly increased which will make them more suitable for various potential applications. This paper presents novel 3D double-U hierarchical structures (DUHs) based on double-V hierarchical structures (DVHs) with tunable Poisson's ratio and Young's modulus by tailoring the geometry parameters. Experimental, numerical and theoretical results show that DUHs have smooth geometry that can reduce manufacturing damage and stress concentration under elastic loading. Another advantage of DUHs is that the curved configurations have enhanced auxetic behavior and higher static collapse stress than DVHs under crushing. The advanced 3D printing technology and those excellent mechanical properties of 3D DUHs meet the requirements of structural and functional applications.
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