Mach-Zehnder-based measurement of light emitting diodes temporal coherence

Objectives: The main objective of this work is to validate a Mach-Zehnder based interferometric method to measure the temporal coherence length of broadband finite size light sources such as Light Emitting Diodes (LEDs), and give a qualitative value of the temporal coherence length of white LEDs, for which nor their spectral width neither their emission peak wavelength are clearly defined. Motivation: Low-coherence light sources such as LEDs have opened many possibilities in applications in which using lasers introduces coherent noise (speckle) that hinders the performance of interferometric measurement techniques. The coherence length is an important characteristic of light sources for scientific applications related to diffraction, holography, tomography, or interferometry. The spatial coherence of a source depends on the distance from the source to the observation plane and its size, while the temporal coherence is related to the emission spectral width and the emission peak wavelength. Therefore, the temporal coherence is a characteristic of each source. Methodology and results: In this work, we use a Mach-Zehnder interferometer for the first time to measure the coherence degree and the temporal coherence length of quasi-monochromatic LEDs. We validate the technique by comparing the results to those obtained directly from the spectrum. Then, we use the tested interferometric method to measure the temporal coherence length of a white LED, for which neither the width of the spectrum nor the emission peak wavelength, are clearly defined. In this case, the Wiener-Khinchin theorem is used to validate the interferometric technique. A very interesting property of the method is that the temporal coherence length is obtained from a single measurement, without needing to perform a scanning. This method can be used also for other non-coherent sources such as halogen lamps, pulsed lasers, and so on. The obtained results will improve the characterization of light sources and the applications dealing with physical optics and electromagnetic interference. © 2022 The Author

Corruption and support for decentralisation

Existing explanations of individual preferences for decentralisation and secession focus on collective identity, economic considerations and party politics. This paper contributes to this literature by showing that preferences for fiscal and political decentralisation are also driven by concern about the quality of government in the face of corruption. It makes two claims. Firstly, information on national‐level corruption decreases satisfaction with national politicians, and subsequently increases preferences for decentralisation and secession. Secondly, information on regional‐level corruption pushes citizens of highly corrupt regions to prefer national retrenchment and unitary states. The effects of this political compensation mechanism crosscut national identities and involve regions that are not ethnically or economically different from the core. We test our argument using a survey experiment in Spain and confirm its cross‐national generalisability with data from the European Values Study

Accurate quantification of apoptosis progression and toxicity using a dielectrophoretic approach

A loss of ability of cells to undergo apoptosis (programmed cell death, whereby the cell ceases to function and destroys itself) is commonly associated with cancer, and many anti-cancer interventions aim to restart the process. Consequently, the accurate quantification of apoptosis is essential in understanding the function and performance of new anti-cancer drugs. Dielectrophoresis has previously been demonstrated to detect apoptosis more rapidly than other methods, and is low-cost, label-free and rapid, but has previously been unable to accurately quantify cells through the apoptotic process because cells in late apoptosis disintegrate, making cell tracking impossible. In this paper we use a novel method based on light absorbance and multi-population tracking to quantify the progress of apoptosis, benchmarking against conventional assays including MTT, trypan blue and Annexin-V. Analyses are performed on suspension and adherent cells, and using two apoptosis-inducing agents. IC50 measurements compared favourably to MTT and were superior to trypan blue, whilst also detecting apoptotic progression faster than Annexin-V

Arc-parallel vs back-arc extension in the Western Gibraltar arc : is the Gibraltar forearc still active?

Extremely tight arcs, framed within the Eurasia-Africa convergence region, developed during the Neogene on both sides of the western Mediterranean. A complex interplate deformation zone has been invoked to explain their structural trend-line patterns, the shortening directions and the development of back-arc basins. Updated structural and kinematic maps, combined with earthquake data covering the complete hinge zone of the western Gibraltar arc help us to explore the mode of strain partitioning from 25My ago to present. During the Miocene, the strain partitioning pattern showed arc-perpendicular shortening in the active orogenic wedge -assessed from the radial pattern of tectonic transport directions- accompained by subhorizontal stretching. Structures accommodating stretching fall into two categories on the basis of their space distribution and their relationships with the structural trend-line pattern: i) arc-parallel stretching structures in the external wedge (mainly normal faults and conjugate strike-slip faults); and ii) extensional faults developed in the hinterland zone in which transport directions are centripetal towards the Alborán back-arc basin. Pliocene to Recent deformational structures together with focal solutions from crustal earthquakes (n=167; 1.

Has cupper ion any effect on Sinorhizobium Melitoili bacteria?

Proceedings of the I Congress PIIISA celebrado en la Estación Experimental del Zaidín, Granada, el 26 de abril de 2012.Sinorhizobium meliloti is a soil bacterium that in symbiosis with Alfalfa leguminous plants fixes N2 to ammonia. This process occurs after an intimate communication between host and microsimbiont in the rhizosphere niche. This soil bacterium may suffer biotic and abiotic stresses in this complex environment. Resistance to any of this stresses can be an advantage for this type of bacteria. In this work we test the effects of Cupper ion in the bacterium Sinorhizobium meliloti. We found an effect on pigmentation and this effect is specific of each isolate (i.e. it is very pronounced for the isolate AK83 from Aral sea in Russia). On the other hand, comparison of Cupper ion resistance phenotype between isolates 1021 and GR4 suggests that the resistance of GR4 could be due to a set of 10 genes found in the cryptic plasmid pRmeGR4a of this strain. However, this resistance phenotype also appears in other isolates, and it could be explained by an alternative phenotype as Exopolysaccaride production (EPS+).It was supported mainly by research project MICINN Consolider‐Ingenio 2010. CSD2009‐00006; Scientific research by Young Students in Science (PIIISA2012; http://emc2astronomy.blogspot.com/).Peer reviewe

Radiografia dels tecno-complexos del Plistocè Superior de la vall de La Femosa (Segrià)

Le complexe de sites a p1cm air de la Femosa a ouvert une nouveile zone d'intérêt pour l'étude du Paléolithique Moyen dans la Catalogne. Les gisements appelés "Les Fonts", "El Set" et "Le Secanet" ont eu une grande importance pour l'essay de Ia systématisation de cettes chronocultures dans notre pays. Sa distribution et ses propes differences nous ont permis d'affermir l'occupation diachronique de ce lieu ainsi que montrer l'intérêt que la diversification téchnologique et typologique a dans le Pléistocène Supérieu

Finding answers in lipid profile in COVID-19 patients

Introduction: A small percentage of patients will develop a severe form of COVID-19 caused by SARS-CoV-2 infection. Thus, it is important to predict the potential outcomes identifying early markers of poor prognosis. In this context, we evaluated the association of SARS-CoV-2 infection with lipid abnormalities and their role in prognosis. Methods: Single-center, retrospective, observational study of COVID-19 patients admitted from March to October 2020. Clinical and laboratory data, comorbidities, and treatments for COVID-19 were evaluated. Main outcomes including intensive care unit (ICU) admission and mortality were analyzed with a multivariable Cox proportional hazards regression model. Results: We selected 1489 from a total of 2038 consecutive patients with confirmed COVID-19, who had a complete lipid profile before ICU admission. During the follow-up performed in 1109 patients, we observed a decrease in T-c, HDL-c, and LDL-c in 28.6%, 42.9%, and 30.4% of patients, respectively, and an increase in TG in 76.8%. The decrease of both T-c and HDL- c was correlated with a decrease in albumin levels (r = 0.39 and r = 0.37, respectively). Kaplan–Meier survival curves found an increased ICU admission in patients with lower T-c (HR 0.55, CI 0.36–0.86), HDL-c (HR 0.61, CI 0.45–0.84), and LDL-c (HR 0.85, CI 0.74–0.97). Higher values of T-c (HR 0.45, CI 0.36–0.57), HDL-c (HR 0.66, CI 0.54–0.81), and LDL-c (HR 0.86, CI 0.78–0.94) showed a protective effect on mortality. Conclusions: Abnormalities in lipid profile are a frequent complication of SARS-CoV-2 infection and might be related to morbidity and mortalityThis work was supported by the following grants: Proyectos de Investigación en Salud (FIS) PI16-02091 and PI19-00584 (funded by Instituto de Salud Carlos III), TIRONET2-CM, B2017/BMD-3724 (funded by Comunidad de Madrid) and cofinanced by FEDER funds to M.M

Radiografia dels tecno-complexos del Plistocè Superior de la Vall de la Femosa (Segrià)

Le complexe de sites a p1ein air de la Femosa a ouvert une nouveile zone d'intérêt pour l'étude du Paléolithique Moyen dans la Catalogne. Les gisements appelés 'Les Fonts', 'El Set' et 'Le Secanet' ont eu une grande importance pour l'essay de Ia systématisation de cettes chronocultures dans notre pays. Sa distribution et ses propes differences nous ont permis d'affermir l'occupation diachronique de ce lieu ainsi que montrer l'intérêt que la diversification téchnologique et typologique a dans le Pléistocène Supérieur

Las fallas del recinto de la Alhambra : Faults in the Alhambra area

The Alhambra is built on a conglomeratic formation, known as the Alhambra Formation, whose age is Pliocene to Lower Pleistocene and has a visible thickness of 200 metres. The western part of the San Pedro escarpment corresponds to a fault-scarp with some retreat; the fault-plane outcrops in the innermost part of the escarpment, showing normal displacement and NW-SE strike with NE steep dip. This fault is the most important one of a set that outcrops along the northern hillslope of the Alhambra. Several topographic steps with NW-SE orientation are interpreted as retreated fault-scarps. In some cases, the activity of these faults seems to be very recent and maybe related to earthquakes. The seismic risk associated with these faults (and maybe some not-outcropping ones) can be taken to be moderate, as some historical damages have been reported concerning the Alhambra walls and the fence. In this respect, the Alhambra fence has numerous cracks geometrically related to fault planes outcropping in the Alhambra Formation, i.e. faults and cracks are continuous and have similar strike and dip. We hypothesize that these cracks are due to small displacements along the faults, occurred during recent earthquakes in the region. These faults constitute mechanical discontinuities, which represent a supplementary risk, because they contribute to reduce the stability of the entire rock massif