Search results for "surface"
showing 10 items of 9345 documents
Highly Sensitive Polarization Rotation Measurement through a High‐Order Vector Beam Generated by a Metasurface
2020
The precise determination of the polarization state of light is fundamental for a vast variety of applications in remote sensing, astronomy, optics and terahertz technology, to name just a few. Typically, polarization characterization is performed by using a combination of multiple optical devices such as beam splitters, polarizers, and waveplates. Moreover, to achieve high-precision, balanced photodetectors and lock-in amplifiers are employed, thus contributing to increasing system complexity. Here, a technique for polarization rotation measurements with a dynamic range of 180° and a sensitivity of about 10−2 degrees is realized using a properly designed metasurface. Such device generates …
Holocene sea level change in Malta
2013
A multidisciplinary approach has been applied to study sea level changes along the coast of Malta using data collected from underwater archaeological remains. The elevation of archaeological markers have been compared with predicted sea level curves providing new bodies of evidence that outline the vertical tectonic behaviour of this region, allowing estimation of the relative sea level changes that occurred in this area of the Mediterranean since the Bronze Age. During the Roman Age, sea level was at −1.36 ± 0.1 m, while in the Midde Age it was at −0.56 ± 0.2 m, in agreement with previous estimations for the Mediterranean region. Data indicate that Malta was tectonically stable during the …
Kinetic evidence for the incorporation of the [(pentamethylcyclopentadienyl) (2,2′-bipyridyl)(aquo)rhodium(III)] complex into DPPC vesicles
2008
Abstract The binding of the [(pentamethylcyclopentadienyl) (2,2′-bipyridyl)(aquo)rhodium(III)] complex [Cp*RhIII(bpy)H2O]2+, to l -α-dipalmitoylphosphatidyl choline (DPPC) vesicles has been estimated by studying the kinetics of the electron transfer reaction between the rhodium(III) complex and formiate ions. Kinetic measurements carried out under anaerobic conditions in absence and presence of DPPC show that the total reaction is composed of two steps. The rate of the first reaction increases with the phospholipid concentration, while that of the second process is independent of the concentration of DPPC. This is consistent with a reaction, where the two reacting species are partitioned be…
L’aire urbaine de Valencia dans le système global des villes : Les effets de la crise économique sur le réseau des liens financiers des entreprises m…
2021
El artículo analiza el impacto que la crisis económica ha tenido sobre las redes de relaciones de propiedad-filiación de las empresas multinacionales, consideradas en la literatura científica como uno de los factores más importantes en la integración de las ciudades en la globalización. El caso de estudio es el área metropolitana de Valencia, un centro de segundo nivel en las redes económicas mundiales que ha sido duramente golpeado por los efectos de la crisis desde 2008. A partir del análisis de bases de datos de empresas multinacionales en dos fechas de referencia, 2010 y 2013, se constata que la crisis económica ha provocado un retroceso en la inserción del área metropolitana en dichas …
Conformational Dynamics of the Dengue Virus Protease Revealed by Fluorescence Correlation and Single-Molecule FRET Studies.
2021
The dengue virus protease (DENV-PR) represents an attractive target for counteracting DENV infections. It is generally assumed that DENV-PR can exist in an open and a closed conformation and that active site directed ligands stabilize the closed state. While crystal structures of both the open and the closed conformation were successfully resolved, information about the prevalence of these conformations in solution remains elusive. Herein, we address the question of whether there is an equilibrium between different conformations in solution which can be influenced by addition of a competitive inhibitor. To this end, DENV-PR was statistically labeled by two dye molecules constituting a FRET …
Evaluation of HBs, HBc, and frCP virus-like particles for expression of human papillomavirus 16 E7 oncoprotein epitopes.
2002
<i>Objectives:</i> In an attempt to develop virus-like particles (VLPs) as experimental vaccine against human papilloma virus (HPV)-induced tumours, the HPV16 E7 oncoprotein epitopes spanning amino acid (aa) residues 35–98 were expressed on three proteins capable of VLP formation: hepatitis B virus (HBV) surface (HBs) and core (HBc) antigens, and RNA phage fr coats (frCP). <i>Methods:</i> The profile of immunoglobulin isotypes induced in Balb/C mice after immunization with purified chimeric proteins was studied. <i>Results:</i> The HBs*-E7(35–54) protein expressing E7 residues 35–54 between residues 139 and 142 of the HBs carrier formed HBs-like particles…
Regional Farmers’ Perception and Societal Issues in Vineyards Affected by High Erosion Rates
2021
We explore the current situation in a viticultural region in Eastern Spain from a holistic and multifaceted research approach, which allowed us to understand the biophysical conditions, economic cost, social impact, and perception of the farmers’ community to the use of catch crops. A survey of the perception of the farmers, and an assessment of the biophysical impact of catch crops (CC) and tillage (C = Control plot) on soil organic matter, bulk density, infiltration capacity (single ring infiltrometer), and runoff generation and soil erosion (rainfall simulation experiments) was carried out. Two representative fields as study sites were selected in Les Alcusses valley, within Els Alforins…
Highly sensitive olfactory biosensors for the detection of volatile organic compounds by surface plasmon resonance imaging
2018
International audience; Nowadays, monitoring of volatile organic compounds (VOCs) is very important in various domains. In this work, we aimed to develop sensitive olfactory biosensors using odorant binding proteins (OBPs) as sensing materials. Three rat OBP3 derivatives with customized binding properties were designed and immobilized on the same chip for the detection of VOCs in solution by surface plasmon resonance imaging (SPRi). We demonstrated that the proteins kept their binding properties after the immobilization under optimized conditions. The obtained olfactory biosensors exhibited very low limits of detection in both concentration (200pM of beta-ionone) and in molecular weight of …
Anticipatory Postural Adjustments and kinematic arm features when postural stability is manipulated
2018
International audience; Beyond the classical paradigm that presents the Anticipatory Postural Adjustments (APAs) as a manner to create forces that counteract disturbances arising from the moving segment during a pointing task, there is a controversial discussion about the role APAs to facilitate the movement and perform a task accurately. In addition, arm kinematics features are classically used to infer the content of motor planning for the execution and the control of arm movements, The present study aimed to disentangle the conflicting role of APAs during an arm-pointing task in which the subjects reach a central diode that suddenly turns on, while their postural stability was manipulate…
Levels and Potential Health Hazards of Chlorinated Pesticidesin Surface Water Samples of Charsadda Area of Pakistan Using SPME-GC-ECD Technique
2021
In the present study, we determined the levels of chlorinated pesticide residues in surface water samples collected from the Charsadda district (KPK, Pakistan). SPME-GC-ECD with COMBI PAL CTC autosampler was used for extraction and analysis of 20 organochlorine pesticides in the collected water samples. For maximum efficiency of the SPME procedure, several parameters were studied, including the extraction and desorption time of the fiber, solution pH, agitation of samples, and stirring speed, etc. This method showed good liner response, with R2 values in the range of 0.9887 to 0.9999 for all pesticides. This method also provided good percent recoveries at 1 µg L−1 (87.5 to 106.0%) and at 2 …