Tunable entanglement distillation of spatially correlated down-converted photons

We report on a new technique for entanglement distillation of the bipartite continuous variable state of spatially correlated photons generated in the spontaneous parametric down-conversion process (SPDC), where tunable non-Gaussian operations are implemented and the post-processed entanglement is certified in real-time using a single-photon sensitive electron multiplying CCD (EMCCD) camera. The local operations are performed using non-Gaussian filters modulated into a programmable spatial light modulator and, by using the EMCCD camera for actively recording the probability distributions of the twin-photons, one has fine control of the Schmidt number of the distilled state. We show that even simple non-Gaussian filters can be finely tuned to a ~67% net gain of the initial entanglement generated in the SPDC process.Comment: 12 pages, 6 figure

Polinización y sistema reproductivo en Adesmia bijuga Phil. (Fabaceae), una especie en peligro crítico en Chile central

Adesmia bijuga Phil. is an endemic shrub in central Chile, classified as a critically endangered species of plant. After more than 100 years since its original description by R. A. Philippi (1884), the species was rediscovered exclusively in two locations of the Maule Region. One of them, Fundo San Pedro-Las Cañas, is close to extinction with a low number of shrubs, occurring in a disturbed habitat due to plantations of Pinus radiata. This study examined the pollination biology and breeding system of A. bijuga in order to explain their small number of shrubs. We estimated composition of pollinator species attracted to flowers and visitation rates. In order to describe its breeding system in A. bijuga we used manipulated treatments to estimate autonomous self-pollination, level of reproductive assurance and pollen limitation. The results of this study indicate that only pollinators from the order Hymenoptera visit A. bijuga. The pollinator assemblage did not show temporary variation during the flowering season, with Bombus dahlbomii as its most frequent visitor. A. bijuga showed a mixed mating system that involves both cross- and self- pollination. The fruit set ranges from 20% to 60% in the absence or presence of pollinators, respectively. This selfing ability would provide reproductive assurance when pollinators fail. The taxon showed ability of asexual formation of seeds without the occurrence of fertilization by agamospermy. Supplemental outcross pollen did not increase female reproductive success, suggesting that the species is not pollen limited. All these factors may help to explain how this species has been able to survive over time in a small and isolated population. Finally, this work discusses how the results of our study can be applied to future A. bijuga conservation measures.Adesmia bijuga Phil. es una especie arbustiva endémica de Chile central, clasificada como especie en peligro crítico. Después de más de 100 años desde su descripción original por R.A. Philippi (1884), la especie fue redescubierta exclusivamente en dos localidades de la Región del Maule. Una de ellas, en el Fundo San Pedro-Las Cañas, se encuentra cercana a la extinción, en un hábitat perturbado debido a plantaciones de Pinus radiata. Este estudio examinó la biología de la polinización y el sistema reproductivo de A.bijuga, que podrían explicar su restringido número de plantas. Se estimó la composición de polinizadores atraídos por las flores y la tasa de visita. Con el objetivo de caracterizar el sistema reproductivo en A. bijuga se realizaron tratamientos manipulativos para cuantificar la capacidad de autofertilización, el nivel de aseguramiento reproductivo y la limitación de polen. Los resultados de este estudio indican que A. bijuga es visitada solamente por polinizadores que pertenecen al orden himenóptera. El ensamble de polinizadores no varió temporalmente durante el periodo de floración, siendo Bombus dahlbomii el visitador más frecuente. A. bijuga presentó un sistema reproductivo mixto, con polinización cruzada y autopolinización. El rango de fructificación varió entre 20% a 60% en ausencia y presencia de polinizadores, respectivamente. Esta capacidad de autopolinización podría proveer de aseguramiento reproductivo cuando los polinizadores fallan. Tratamientos con suplemento de polen no incrementaron el éxito reproductivo, sugiriendo que la especie no se encuentra limitada de polen. El taxon mostró capacidad de formar semillas asexualmente sin la ocurrencia de fertilización (agamospermia). Todos estos factores podrían ayudar a explicar cómo esta especie es capaz de persistir en el tiempo en una población pequeña y aislada. Finalmente, este trabajo discute cómo los resultados de este estudio pueden ser aplicados en futuras medidas para la conservación de A. bijuga

Regulatory estimates for defaulted exposures: A case study of Spanish mortgages

The capital requirements derived from the Basel Accord were issued with the purpose of deploying a transnational regulatory framework. Further regulatory developments on risk measurement is included across several documents published both by the European Banking Authority and the European Central Bank. Among others, the referred additional documentation focused on the models’ estimation and calibration for credit risk measurement purposes, especially the Advanced Internal-Ratings Based models, which may be estimated both for non-defaulted and defaulted assets. A concrete proposal of the referred defaulted exposures models, namely the Expected Loss Best Estimate (ELBE) and the Loss Given Default (LGD) in-default, is presented. The proposed methodology is eventually calibrated on the basis of data from the mortgage’s portfolios of the six largest financial institutions in Spain. The outcome allows for a comparison of the risk profile particularities attached to each of the referred portfolios. Eventually, the economic sense of the results is analyzed.Regional Government of Andalusia, Spain (Research Group SEJ-555)

Forecasting for regulatory credit loss derived from the COVID-19 pandemic: A machine learning approach

The economic onslaught of the COVID-19 pandemic has compromised the risk management of financial institutions. The consequences related to such an unprecedented situation are difficult to foresee with certainty using traditional methods. The regulatory credit loss attached to defaulted mortgages, so-called expected loss best estimate (ELBE), is forecasted using a machine learning technique. The projection of two ELBEs for 2022 and their comparison are presented. One accounts for the outbreak’s impact, and the other presumes the nonexistence of the pandemic. Then, it is concluded that the referred crisis surely adversely affects said high-risk portfolios. The proposed method has excellent performance and may serve to estimate future expected and unexpected losses amidst any event of extraordinary magnitud

Using synchronization to improve earthquake forecasting in a cellular automaton model

A new forecasting strategy for stochastic systems is introduced. It is inspired by the concept of anticipated synchronization between pairs of chaotic oscillators, recently developed in the area of Dynamical Systems, and by the earthquake forecasting algorithms in which different pattern recognition functions are used for identifying seismic premonitory phenomena. In the new strategy, copies (clones) of the original system (the master) are defined, and they are driven using rules that tend to synchronize them with the master dynamics. The observation of definite patterns in the state of the clones is the signal for connecting an alarm in the original system that efficiently marks the impending occurrence of a catastrophic event. The power of this method is quantitatively illustrated by forecasting the occurrence of characteristic earthquakes in the so-called Minimalist Model.Comment: 4 pages, 3 figure

Progress in development of photocatalytic processes for synthesis of fuels and organic compounds under outdoor solar light

With photovoltaics becoming a mature, commercially feasible technology, society is willing to allocate resources for developing and deploying new technologies based on using solar light. Analysis of projects supported by the European Commission in the past decade indicates exponential growth of funding to photocatalytic (PC) and photoelectrocatalytic (PEC) technologies that aim either at technology readiness levels (TRLs) TRL 1–3 or TRL > 3, with more than 75 Mio€ allocated from the year 2019 onward. This review provides a summary of PC and PEC processes for the synthesis of bulk commodities such as solvents and fuels, as well as chemicals for niche applications. An overview of photoreactors for photocatalysis on a larger scale is provided. The review rounds off with the summary of reactions performed at lab scale under natural outdoor solar light to illustrate conceptual opportunities offered by solar-driven chemistry beyond the reduction of CO2 and water splitting. The authors offer their vision of the impact of this area of research on society and the economy

Perceived quality of life and the specific physical activities by the elderly

Se analizaron indicadores de salud con respecto a la percepción de la calidad de vida (CVRS) mediante el cuestionario Short Form-36 Health Survey (SF-36) y parámetros cinemáticos manifestados en el movimiento press banca (12 kilos) como predictores de las adaptaciones neurofisiológicas que se producen con la actividad física. Se trataron valores de potencia, de velocidad, aceleraciones, fuerza y variables temporales. Se utilizaron dos grupos, uno activo, de práctica física habitual (12H, 6M, 68,4±5,6 años, 1,65±0,074m, 74,57±15,41kg, BMI 26,93±4,02; act/sem 4,5±1,65h.), y otro sedentario (16H, 7M, 69 ± 7,07 años, 1,67 ± 0,072m, 74,95 ± 7,4kg, BMI 26,84±2,78) Se encontraron diferencias significativas (p<0,05;gl=1,39;dz=0,5). El grupo considerado activo se percibe con mejor calidad de vida y manifiesta de manera más rápida y con mayor fuerza el movimiento solicitado. Las conclusiones son relevantes para posteriores estudios que se centren en la pérdida de propiedades neuromusculares acompañada a la falta de práctica y al efecto del envejecimiento.Quality of life related to health indicators (QLRH) were analyzed by means of the Short Form-36 Health Survey (SF-36) questionnaire and the specified kinetic parameters of the bench press movement (12 kg) as predictors of the neurophysiological adaptations produced by physical activity. These were the values of power, velocity, acceleration, strength and temporal variables. Two groups were studied: the first group was active, undertaking regular physical activity (12 male; 6 female; 68,4±5,6 years; 1,65±0,074m; 74,57±15,41kg; BMI 26,93±4,02; weekly activity 4,5±1,65h.); the second group was sedentary (16 male; 7 female; 69±7,07 years; 1,67±0,072m; 74,95±7,4kg; BMI 26,84±2,78). Significant differences were found (p<0,05;df=1,39;dz=0,5). The group regarded as active considered itself as having a better quality of life and was able to perform the requested movement with greater speed and strength. The conclusions are relevant for future studies that centre on the loss of neuromuscular properties accompanied by a lack of physical activity and the effects of aging

High-dimensional decoy-state quantum key distribution over 0.3 km of multicore telecommunication optical fibers

Multiplexing is a strategy to augment the transmission capacity of a communication system. It consists of combining multiple signals over the same data channel and it has been very successful in classical communications. However, the use of enhanced channels has only reached limited practicality in quantum communications (QC) as it requires the complex manipulation of quantum systems of higher dimensions. Considerable effort is being made towards QC using high-dimensional quantum systems encoded into the transverse momentum of single photons but, so far, no approach has been proven to be fully compatible with the existing telecommunication infrastructure. Here, we overcome such a technological challenge and demonstrate a stable and secure high-dimensional decoy-state quantum key distribution session over a 0.3 km long multicore optical fiber. The high-dimensional quantum states are defined in terms of the multiple core modes available for the photon transmission over the fiber, and the decoy-state analysis demonstrates that our technique enables a positive secret key generation rate up to 25 km of fiber propagation. Finally, we show how our results build up towards a high-dimensional quantum network composed of free-space and fiber based linksComment: Please see the complementary work arXiv:1610.01812 (2016