Search results for "Blue"
showing 10 items of 487 documents
Hydrogels for potential colon drug release by thiol-ene conjugate addition of a new inulin derivative.
2008
Inulin was chosen as a starting polymer for biocompatible, pH-sensitive and biodegradable hydrogels. Three INUDVSA-TT hydrogels were obtained by crosslinking inulin derivatives with trimethylolpropane tris(3-mercaptopropionate) under varying conditions. The resulting hydrogels were cell compatible, as demonstrated by MTS and trypan blue exclusion assays acting on Caco-2 cells, and were biodegraded by inulinase and esterase, thus suggesting their use as colonic drug delivery systems. 2-Methoxyestradiol, an anti-cancer drug, was soaked in INUDVSA-TT hydrogels and its in vitro release and apoptotic effect on Caco-2 cells were evaluated.
Long-range & Self-powered IoT Devices for Agriculture & Aquaponics Based on Multi-hop Topology
2019
This article presents the prototype design and testing of a long-range, self-powered IoT devices for use in precision agriculture and aquaponics. The devices are designed using the ultra-low power nRF52840 microcontroller with Bluetooth 5 support and ambient energy harvesting. A power of 942µW is harvested in an indoor environment. The devices are therefore suitable for both indoor and outdoor use, as natural sunlight will provide far more energy compared to artificial indoor lights. A line-of-sight range of up to 1.8km is achieved with the use of coded transmissions. However, the coverage area and range can be extended significantly by deploying the devices in multi-hop network topology. T…
Electrochemical Characterization of Egyptian Blue Pigment in Wall Paintings Using the Voltammetry of Microparticles Methodology
2013
The solid state voltammetric response of Egypt blue, Han blue and ploss blue pigments upon attachment to graphite electrodes in contact with aqueous phosphate buffer at pH 7.0 is studied by voltammetry of microparticles and scanning electrochemical microscopy. Such voltammetric responses, combined with those for synthetic specimens consisting of binary mixtures of the pigment and SiO2 or CaCO3 as well as ternary ones of CaCO3 and SiO2 mixtures allow for the identification of the pigment and the support in samples from wall paintings using different electrochemical parameters, in particular upon performing the Tafel and modified Tafel analysis of voltammetric peaks. Identification of Egypt b…
Enhancing the electrocatalytic activity and stability of Prussian blue analogues by increasing their electroactive sites through the introduction of …
2021
Prussian blue analogues (PBAs) have been proven as excellent Earth-abundant electrocatalysts for the oxygen evolution reaction (OER) in acidic, neutral and alkaline media. Further improvements can be achieved by increasing their electrical conductivity, but scarce attention has been paid to quantify the electroactive sites of the electrocatalyst when this enhancement occurs. In this work, we have studied how the chemical design influences the specific density of electroactive sites in different Au-PBA nanostructures. Thus, we have first obtained and fully characterized a variety of monodisperse core@shell hybrid nanoparticles of Au@PBA (PBA of NiIIFeII and CoIIFeII) with different shell siz…
Glutathione regulates telomerase activity in 3T3 fibroblasts.
2004
Changes in telomerase activity have been associated either with cancer, when activity is increased, or with cell cycle arrest when it is decreased. We report that glutathione, a physiological antioxidant present at high intracellular concentrations, regulates telomerase activity in cells in culture. Telomerase activity increases in 3T3 fibroblasts before exponential cell growth. The peak of telomerase activity takes place 24 h after plating and coincides with the maximum levels of glutathione in the cells. When cells are treated with buthionine sulfoximine, which decreases glutathione levels in cells, telomerase activity decreases by 60%, and cell growth is delayed. Glutathione depletion in…
Preamble Sampling MAC Protocol for Low Power Wireless Sensor Networks with IEEE 802.15.4 Transceivers
2006
In this paper a preamble sampling MAC protocol for low power wireless sensor networks is proposed. The article describes the implementation of the protocol using network nodes equipped with the Chipcon CC2420 802.15.4 transceiver. The power consumption of the transceiver has been measured and the MAC protocol has been adapted to the transceiver properties. The results show the trade-off between power consumption and transmission delay for this algorithm during the communication process.
Meanings of travel in the musical discourse of blues: Roosevelt “Grey Ghost” Williams and “Lonesome Traveller”
2016
El objetivo de este artículo es investigar, desde una perspectiva comunicativa, socio-semiótica y etnomusicológica, la construcción de sentido sobre el viaje y el estilo de vida itinerante (hobo) en el discurso musical del blues. Primero realizaremos una contextualización histórica del viaje en la tradición afroamericana, y después analizaremos el caso del legendario músico texano Roosevelt «Grey Ghost» Williams (1903-1996) y de su composición «Lonesome Traveller» («viajero solitario»), en la que se representa el sujeto y estilo de vida hobo (trabajador migrante y sin hogar). En ese proceso, discutiremos el sentido del viaje como imposición y el sentido del viaje como signo de independencia…
A New FEC Scheme for Real-time Transmission of High Definition Video over IP Network
2007
Increasing the applicability of ubiquitous computing, minimizing energy consumption and hardware cost are mandatory in real world applications. In this paper we present our platform prototype for ubiquitous computing, which has been implemented based on commercial Bluetooth off-the-shelf components. It allows every object to be augmented with processing and communication capabilities in order to make them "smart". We validate our proposal by evaluating the trade-off between power consumption and performance of the experimental prototype.
Building a research prototype to provide pervasive services in hospitals
2008
Research into the nature of pervasive computing has now been around for more than a decade. Nowadays pervasive applications exploit mobile wireless communication technologies to interconnect computing devices along with various sensing technologies, setting up a new kind of intelligent environment where applications can transparently search and use services without userspsila intervention. However, there are few examples of real world deployment of pervasive computing moving out from academic laboratories into our everyday life. We present BlueHospital - a research prototype that provides context-aware information and location based services to clinicians in hospitalspsila recovery wards. T…
Software Requirements for Ubiquitous Ad Hoc Mobile Networks: An Example of a Bluetooth Application
2009
In contrast with the simple and elegant concept of global computing, also called ubiquitous computing - where daily life objects get now computing capacity and interact among them to provide a wide range of services to users - a major difficulty is arising with the software engineering process to develop applications for these devices. This article discusses the additional parameters that should be taken into account when designing and developing software for ubiquitous devices in ad-hoc networks. In these networks the mobility of the devices could increase the complexity of the requirements to be considered. As a case study, we present a Bluetooth application that has been developed to ful…