6,506 research outputs found

    Acoustic charge transport in n-i-n three terminal device

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    We present an unconventional approach to realize acoustic charge transport devices that takes advantage from an original input region geometry in place of standard Ohmic input contacts. Our scheme is based on a n-i-n lateral junction as electron injector, an etched intrinsic channel, a standard Ohmic output contact and a pair of in-plane gates. We show that surface acoustic waves are able to pick up electrons from a current flowing through the n-i-n junction and steer them toward the output contact. Acoustic charge transport was studied as a function of the injector current and bias, the SAW power and at various temperatures. The possibility to modulate the acoustoelectric current by means of lateral in-plane gates is also discussed. The main advantage of our approach relies on the possibility to drive the n-i-n injector by means of both voltage or current sources, thus allowing to sample and process voltage and current signals as well.Comment: 9 pages, 3 figures. Submitted to Applied Physics Letter

    Finite dimensional corrections to mean field in a short-range p-spin glassy model

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    In this work we discuss a short range version of the pp-spin model. The model is provided with a parameter that allows to control the crossover with the mean field behaviour. We detect a discrepancy between the perturbative approach and numerical simulation. We attribute it to non-perturbative effects due to the finite probability that each particular realization of the disorder allows for the formation of regions where the system is less frustrated and locally freezes at a higher temperature.Comment: 18 pages, 5 figures, submitted to Phys Rev

    Three resilient megastructures by Pier Luigi Nervi

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    Resilience, as the ability of a structure to withstand threats and continue to function, it is normally related to durability and performance to accepted standards over time. The resilience of a structure can be threatened by poor design, changes in the public's perception of style, the potential for a change-in-use and structural attack; catastrophic events such as fire, explosion or impact are usually considered the main threats for Resilience. In the contemporary built environment Resilience is considered increasingly important; it has, in fact, become one of the major design issues, especially for large, iconic or public and prominent structures: this has not always been the case. Following the Second World War, building designers faced the necessity to conceive projects within severe financial constraints, hence the proliferation of a low quality and limited life-span structures; buildings which were designed to be replaceable, cheap and perhaps anonymous. This was thought to be an effec-tive answer to quickly accommodate the large number of people moving towards the urban environment partly destroyed by the WWII. These very buildings now constitute the backbone of our urban scenery and although some still function adequately, many are perfect examples of structures which exhibit a lack of re-silience. Fortunately, there were a few designers who refused this post-war tendency and attempted to design lasting structures of quality: most of them were engineers. This is not a coincidence, engineers had less to do with the issue of providing residential accommodations and more with the erection of large structures which necessitated a higher quality control on materials and technologies: Pier Luigi Nervi was one of them. This work considers three large structures designed and built fifty years ago,in 1961, by the Italian engineer. The structures are the Bus Station at the George Washington Bridge in New York (USA); The Burgo Paper Mill in Mantua (Italy); and the Palace of Labour in Turin (Italy). All of these buildings are hybrid structures (concrete and steel), an unusual choice for Nervi that perhaps reects the design climate at the time; These buildings reacted quite differently to the events that have occurred over the past half century. One of the key factors to achieve resilience it is considered to be the quality of the buildings, which includes their ability to perform maintenance. The lack of which for whatever reason, this paper aims to demonstrate, will inevitably result in a weak performance in terms of resilience on the long run

    Validity and reliability of a light-based electronic target for testing response time in fencers

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    Response time is a fencing fundamental sensorimotor skill. Therefore, the aim of the current study was to examine the efficacy of a light-based electronic target in fencers, designed to measure and train this entity. Ninety-five fencers (M=53; F=42) were tested in regard to their response time, using a light-based electronic target, for three different attack types: simple attack, the lunge, and an attack following a 1.5-m thrust. All participants were divided into elite vs. novice fencers. Elite fencers had national and international rankings, and were again divided with regard to used weapon: épéeists (n=32; M=19; F=13) and foilists (n=30; M=13; F=17). Measurement was evaluated for validity/reliability, sensitivity/specificity, and correlation. Reliability was high for all attack types (ICC 0.94-0.96). Lower response times were found in males for two attack types with good sensitivity (81-93%)/specificity (50-91%) for all attack types. Elite fencers responded faster than novice fencers for all attack types (P<0.001), whereas elite males were faster than females for two attack types (P<0.01). Lower response times in females correlated with level for one attack type (r=0.797, P<0.05). In conclusion, the light-based electronic target system was found to be highly reliable and therefore could be used by fencing athletes as a further measure of performance

    Deciphering the Interplay between Binders and Electrolytes on the Performance of Li4Ti5O12 Electrodes for Li-Ion Batteries

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    Lithium titanium oxide (Li4Ti5O12, LTO) is an attractive negative electrode for the development of safe-next-generation-lithium-ion batteries (LIBs). LTO can find specific applications complementary to existing alternatives for LIBs thanks to its good rate capability at high C-rates, fast lithium intercalation, and high cycling stability. Furthermore, LIBs featuring LTO electrodes are inherently safer owing to the LTO's operating potential of 1.55 V vs. Li+/Li where the commonly used organic-based electrolytes are thermodynamically stable. Herein, we report the combined use of water-soluble sodium alginate (SA) binder and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)-tetraglyme (1m-T) electrolyte and we demonstrate the improvement of the electrochemical performance of LTO-based electrodes with respect to those operating in conventional electrolyte 1M LiPF6-ethylene carbonate: dimethyl carbonate (LP30). We also tackle the analysis of the impact of combining the binder/electrolyte on the long-term cycling performance of LTO electrodes featuring SA or conventional polyvinylidene fluoride (PVdF) as binders. Therefore, to assess the impact of the combination of binder/electrolyte on performance, we performed post-mortem characterization by ex situ synchrotron diffraction experiments of LTO electrodes after cycling in LP30 and 1m-T electrolytes

    Menarche, Menstruation, Menopause and Mental Health (4M): a consortium facilitating interdisciplinary research at the intersection of menstrual and mental health

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    This is the final version. Available on open access from Frontiers Media via the DOI in this record. Data availability statement: The original contributions presented in the study are included in the article/Supplementary Material, further inquiries can be directed to the corresponding author.Menstrual and mental health form a close relationship that is under-appreciated in scientific research, clinical practice and social policy. This association is extremely complex, involving interactions between biology, psychology and social, political and structural influences on health and wellbeing. Research in these areas has traditionally been siloed: focusing on menstrual or mental health in isolation, or the interrelation from a limited one-dimensional perspective. We recognised the need for a more holistic and comprehensive approach that considers the complex interweaving nature of menstrual and mental health. In 2021, we established the Menarche, Menstruation, Menopause and Mental Health (4M) consortium as a tool to address this gap and to facilitate interdisciplinary research. This paper provides a comprehensive source of information about 4M for researchers and stakeholders who may be interested in joining or working with the consortium.GW4 Allianc
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