Alterations in human EEG activity caused by extremely low frequency electromagnetic fields

This study has investigated whether extremely low frequency (ELF) electromagnetic fields (EMFs) can alter human brain activity. Linearly polarised magnetic flux density of 20Â-T (rms) was generated using a standard double Helmholtz coils and applied to the human head over a sequence of 1 minute stimulations followed by one minute without stimulation in the following order of frequencies 50, 16.66, 13, 10, 8.33 and 4Hz. We collected recordings on 33 human volunteers under double-blind counter-balanced conditions. Each stimulation lasted for two minutes followed by one minute post-stimulation EEG recording. The same procedure was repeated for the EMF control sessions, where the order of control and exposure sessions was determined randomly according to the subject's ID number. The rest period between two conditions (exposure and control) was 30 minutes. The results indicate that there was a significant increase in Alpha1, Alpha2, and Beta1 at the frontal brain region, and a significant decrease in Alpha2 band in parietal and occipital region due to EMF exposure

Síntesis de un revestimiento nanocompuesto basado en TiO2/ZnAl hidróxidos dobles en capas

The aim of this investigation was the synthesis of nanocomposite coatings based on Zn-Al layered double hydroxides (Zn-Al LDH) and TiO2. The Zn-Al LDH material, which acted as the catalyst support of the active TiO2 component (in the content of 3 and 10 wt. %), was synthesized by a low super saturation co-precipitation method. The interaction between the Zn-Al LDH and the active TiO2 component was accomplished by using vacuum evaporation prior to the mechanical activation and only by mechanical activation. The final suspension based on Zn-Al LDH and 10wt. % TiO2, impregnated only by mechanical activation, showed the optimal characteristics from the aspect of particle size distribution and XRD analysis. These properties had a positive effect on the functional properties of the coatings (photocatalytic activity and self-cleaning efficiency) after the water rinsing procedure.El objetivo de esta investigaci.n fue la preparaci.n de recubrimientos de nanocompuestos basados en Zn-Al hidr.xidos dobles en capas (Zn-Al LDH) y TiO2. El material de LDH Zn-Al, que actuaba como catalizador del componente activo TiO2 (en el contenido de 3 y 10 en peso.%), se sintetiz. por un m.todo de co-precipitaci.n con baja sobresaturaci.n. La interacci.n entre el Zn-Al LDH y el componente activo TiO2 se llev. a cabo mediante el uso de la evaporaci.n al vac.o antes de la activaci.n mec.nica y s.lo por activaci.n mec.nica. La suspensi.n final basada en Zn-Al LDH y 10wt. % TiO2, impregnada solamente por la activaci.n mec.nica, mostr. las caracter.sticas .ptimas desde el aspecto de la distribuci.n de tama.o de part.cula y an.lisis de XRD. Estas propiedades ten.an un efecto positivo sobre las propiedades funcionales de los revestimientos (actividad fotocatal.tica y eficiencia de auto-limpieza) despu.s del procedimiento de aclarado de agua

Preparación y caracterización de un recubrimiento protector autolimpiante de TiO2/caolín

The application of self-cleaning coatings presents one of the most effective ways to protect the surfaces of the building materials. The effect of TiO2/kaolin based coatings applied to three types of substrates: non-porous, porous and highly porous, was investigated. Mechanical activation was applied for the impregnation of the active TiO2 component (in content of 3 and 10 wt. %) into the kaolin support. Surface properties (roughness, hydrophilicity and micro-hardness) and functional properties (photocatalytic activity and self-cleaning efficiency) were studied in order to define the optimal formulation of the applied coatings. The effect of the photocatalytic behavior of the coated substrates in terms of self-cleaning ability was assessed by the photodegradation of Rhodamine B, performed before and after durability tests. The results obtained in this paper showed that photocatalytic activity of the TiO2/kaolin composite coating generally depends on the procedure of TiO2 impregnation into the kaolin clay and the loaded TiO2 content.La aplicación de recubrimientos autolimpiantes presenta una de las maneras más efectivas de proteger las superficies de los materiales de construcción. Se ha investigado el efecto de recubrimientos basados en TiO2/caolín, aplicados sobre tres tipos de sustratos: no poroso, poroso y altamente poroso. Se utilizó activación mecánica para la impregnación del componente de TiO2 activo (en contenido del 3 y 10% en peso) sobre el soporte de caolín. Se han estudiado las propiedades superficiales (rugosidad, hidrofilicidad y microdureza) y las propiedades funcionales (actividad fotocatalítica y eficacia autolimpiante) para definir la formulación óptima de las capas aplicadas. El efecto del comportamiento fotocatalítico de los sustratos revestidos en términos de capacidad de autolimpieza se evaluó mediante la fotodegradación de Rodamina B, realizada antes y después de las pruebas de durabilidad. Los resultados obtenidos en este trabajo mostraron que la actividad fotocatalítica del revestimiento de TiO2/ caolín, dependen en general del procedimiento de impregnación de TiO2 en la capa de caolín y el contenido utilizado de TiO2

A Generic Architecture for Integrating Health Monitoring and Advanced Care Provisioning

This paper presents a novel approach for advanced person- alized care and health services. It consists of four tiers and presents a high level of openness, privacy and manageability compared to existing systems. Moreover, the architecture is driven by realistic underlying business opportunities and is validated through the design of multiple scenarios.status: publishe

Uso de cenizas volantes y fosfoyesos en la síntesis de clínkeres belíticos de sulfoaluminatos

Fly ash and phosphogypsum were used as Naturally Occurring Radioactive Materials (NORM) by-products for the synthesis of belite-sulfoaluminate clinkers. The influence of raw mixture composition and firing temperature was investigated. Clinkers and cements were examined by X-ray powder diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy. The compressive strength of the cements was determined after 28 days. Clinker phases identified included ye’elimite, ß-phase of belite, ternesite and gehlenite, while the main hydration product of the cement pastes was ettringite. The results showed that belite-sulfoaluminate cements can be fabricated with a compressive strength of 45.9 N/mm2 by firing the raw mixture (70 wt.% marl, 10 wt.% bauxite and 20 wt.% phosphogypsum) at a temperature of 1320°C/1h.En este estudio se han utilizado cenizas volantes y fosfoyeso como Naturally Occurring Radioactive Materials (NORM) para la síntesis de clínkeres belíticos de sulfoaluminatos. Se ha investigado la influencia de la composición de la materia prima y de las diferentes temperaturas de cocción. Los clínkeres y cementos se examinaron mediante difracción de rayos X y microscopía electrónica de barrido equipada con espectroscopía de energía dispersiva de rayos X. Los valores de compresión de los cementos se determinaron a la edad de 28 días. Las fases constituyentes de los clínkeres se identificaron como ye’elimita, fase-ß de la belita, ternesita y gehlenita, mientras que el principal producto de hidratación de la pasta de cemento se identificó como ettringita. Los resultados muestran que los cementos belíticos de sulfoaluminatos pueden ser fabricados con una resistencia a compresión de 45.9 N/mm2 mediante una cocción de la materia prima (70 % en peso de marga, 10 % de bauxita y 20 % de fosfoyeso) a una temperatura de 1320°C/1

Asymmetric optical nuclear spin pumping in a single uncharged quantum dot

A highly asymmetric dynamic nuclear spin pumping is observed in a single self assembled InGaAs quantum dot subject to resonant optical pumping of the neutral exciton transition leading to a large maximum polarization of 54%. This dynamic nuclear polarization is found to be much stronger following pumping of the higher energy Zeeman state. Time-resolved measurements allow us to directly monitor the buildup of the nuclear spin polarization in real time and to quantitatively study the dynamics of the process. A strong dependence of the observed dynamic nuclear polarization on the applied magnetic field is found, with resonances in the pumping efficiency being observed for particular magnetic fields. We develop a model that fully accounts for the observed behaviour, where the pumping of the nuclear spin system is due to hyperfine-mediated spin flip transitions between the states of the neutral exciton manifold.Comment: published version; 4+ pages, 3 figures (eps

Highly Non-linear Excitonic Zeeman Spin-Splitting in Composition-Engineered Artificial Atoms

Non-linear Zeeman splitting of neutral excitons is observed in composition engineered In(x)Ga(1-x)As self-assembled quantum dots and its microscopic origin is explained. Eight-band k.p simulations, performed using realistic dot parameters extracted from cross-sectional scanning tunneling microscopy, reveal that a quadratic contribution to the Zeeman energy originates from a spin dependent mixing of heavy and light hole orbital states in the dot. The dilute In-composition (x<0.35) and large lateral size (40-50 nm) of the quantum dots investigated is shown to strongly enhance the non-linear excitonic Zeeman gap, providing a blueprint to enhance such magnetic non-linearities via growth engineering

Regulatory Taking: A Contract Approach

This Article begins by defining the parameters of the fifth amendment\u27s taking clause. The Article then reviews the various tests used in determining whether governmental action constitutes a taking, and discusses the recent Supreme Court decisions within the framework of case law as it has evolved since the Court\u27s 1922 landmark decision, Pennsylvania Coal Co. v. Mahon. Finally, the Article suggests a formula based on well-established contract principles for analyzing the impact of land use regulation on private property interests

PRODUCTION OF GLASS-CERAMICS FROM WASTE MATERIALS AND OPTIMIZATION OF THE MAIN PROCESS PARAMETERS

In this study the 3D surface model was successfully applied in investigating the influence of the process parameters on the physical and mechanical properties of the glass-ceramics. Glassceramics was produced from coal fly ash and waste glass through the sintering method. The raw material was taken from “REK Bitola”, a thermal power plant in the Republic of Macedonia. Glass-ceramics was obtained through the process of consolidation. Compacts with different ratio of fly ash and waste glass were pressed at 45 MPa, sintered in the temperature interval from 1000 to 11000C, and isothermal time at the final temperature from 1h to 5h. The process of optimization was conducted on the process parameters such as quantity of glass, sintering temperature and isothermal time. According to the results of the process of optimization presented by the software package, a final model equations of the density and bending strength dependence were obtained

Semiconductor nanostructures engineering: Pyramidal quantum dots

Pyramidal quantum dots (QDs) grown in inverted recesses have demonstrated over the years an extraordinary uniformity, high spectral purity and strong design versatility. We discuss recent results, also in view of the Stranski-Krastanow competition and give evidence for strong perspectives in quantum information applications for this system. We examine the possibility of generating entangled and indistinguishable photons, together with the need for the implementation of a, regrettably still missing, strategy for electrical control