Electronic transport in locally gated graphene nanoconstrictions

We have developed the combination of an etching and deposition technique that enables the fabrication of locally gated graphene nanostructures of arbitrary design. Employing this method, we have fabricated graphene nanoconstrictions with local tunable transmission and characterized their electronic properties. An order of magnitude enhanced gate efficiency is achieved adopting the local gate geometry with thin dielectric gate oxide. A complete turn off of the device is demonstrated as a function of the local gate voltage. Such strong suppression of device conductance was found to be due to both quantum confinement and Coulomb blockade effects in the constricted graphene nanostructures.Comment: 3 pages 3 figures; separated and expanded from arXiv:0705.3044v

On the Hardware Implementation of Triangle Traversal Algorithms for Graphics Processing

Current GPU architectures provide impressive processing rates in graphical applications because of their specialized graphics pipeline. However, little attention has been paid to the analysis and study of different hardware architectures to implement specific pipeline stages. In this work we have identified one of the key stages in the graphics pipeline, the triangle traversal procedure, and we have implemented three different algorithms in hardware: bounding-box, zig-zag and Hilbert curve-based. The experimental results show that important area-performance trade-offs can be met when implementing key image processing algorithms in hardwar

Electronic Transport in Dual-gated Bilayer Graphene at Large Displacement Fields

We study the electronic transport properties of dual-gated bilayer graphene devices. We focus on the regime of low temperatures and high electric displacement fields, where we observe a clear exponential dependence of the resistance as a function of displacement field and density, accompanied by a strong non-linear behavior in the transport characteristics. The effective transport gap is typically two orders of magnitude smaller than the optical band gaps reported by infrared spectroscopy studies. Detailed temperature dependence measurements shed light on the different transport mechanisms in different temperature regimes.Comment: 4 pages, 3 figure

Excited state spectroscopy in carbon nanotube double quantum dots

We report on low temperature measurements in a fully tunable carbon nanotube double quantum dot. A new fabrication technique has been used for the top-gates in order to avoid covering the whole nanotube with an oxide layer as in previous experiments. The top-gates allow us to form single dots, control the coupling between them and we observe four-fold shell filling. We perform inelastic transport spectroscopy via the excited states in the double quantum dot, a necessary step towards the implementation of new microwave-based experiments.Comment: 16 pages, 6 figures, submitted to nanoletter

The Use of Sensors to Prevent, Predict Transition to Chronic and Personalize Treatment of Low Back Pain: A Systematic Review

Non-specific low back pain (NSLBP) is a highly prevalent condition that implies substantial expenses and affects quality of life in terms of occupational and recreational activities, physical and psychological health, and general well-being. The diagnosis and treatment are challenging processes due to the unknown underlying causes of the condition. Recently, sensors have been included in clinical practice to implement its management. In this review, we furthered knowledge about the potential benefits of sensors such as force platforms, video systems, electromyography, or inertial measure systems in the assessment process of NSLBP. We concluded that sensors could identify specific characteristics of this population like impaired range of movement, decreased stability, or disturbed back muscular activation. Sensors could provide sufferers with earlier diagnosis, prevention strategies to avoid chronic transition, and more efficient treatment approaches. Nevertheless, the review has limitations that need to be considered in the interpretation of results.FEDER/Aragon Government—Dept. of Science, University, and the Knowledge Society. Grant number [LMP97_21

Are Antarctic Specially Protected Areas safe from plastic pollution? a survey of plastic litter at Byers Peninsula, Livingston Island, Antarctica

A number of studies have reported in the last decades the presence of plastics in the Southern Ocean, which are liable to reach the coast and accumulate on the Antarctic Continent. Despite this, there are few data on the amount of plastic pollution on Antarctic beaches below 60°S. Here we provide valuable information about the presence of plastic debris in Byers Peninsula, Livingston Island, South Shetland Islands, an Antarctic Specially Protected Area (ASPA) and a hotspot for biodiversity. A total of 129 locations with between 1 and 5 items were recorded among the 3 survey sites on Byers Peninsula. Most of the observed items are likely to derive from fishing and local sources such as tourism and research activities. We discuss the potential impacts of their presence on local fauna and some of the consequences on the Antarctic ecosystem. From this survey of plastic accumulation in an ASPA, we propose the implementation of mitigation strategies, such as systematic monitoring of the abundance and distribution of plastic waste, in order to identify trends in marine debris and control the levels of plastic pollution in the Maritime Antarctic region.This work was supported by the Spanish Agencia Estatal de Investigación (AEI), Grant no. CTM2016-79741-R. PA is supported by a FPI-contract fellowship (Grant no. BES-2017 080558) from Spanish Ministerio de Economia y Competividad (MINECO)