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The black hole information puzzle can be resolved if two conditions are met. Firstly, if the information of what falls inside a black hole remains encoded in degrees of freedom that persist after the black hole completely evaporates. These degrees of freedom should be capable of purifying the information. Secondly, if these purifying degrees of freedom do not significantly contribute to the system's energy, as the macroscopic mass of the initial black hole has been radiated away as Hawking radiation to infinity. The presence of microscopic degrees of freedom at the Planck scale provides a natural mechanism for achieving these two conditions without running into the problem of the large pair-creation probabilities of standard remnant scenarios. In the context of Hawking radiation, the first condition implies that correlations between the 'in' and 'out' Hawking partner particles need to be transferred to correlations between the microscopic degrees of freedom and the 'out' partners in the radiation. This transfer occurs dynamically when the 'in' partners reach the singularity inside the black hole, entering the UV regime of quantum gravity where the interaction with the microscopic degrees of freedom becomes strong. The second condition suggests that the conventional notion of the vacuum's uniqueness in quantum field theory should fail when considering the full quantum gravity degrees of freedom. In this paper, we demonstrate both key aspects of this mechanism using a solvable toy model of a quantum black hole inspired by loop quantum gravity., Comment: arXiv admin note: text overlap with arXiv:2301.03951, arXiv:1703.09149

The benefits of continuous glucose monitoring (CGM) in diabetes management are extensively documented. Yet, the broader adoption of CGM systems is limited by their cost and invasiveness. Current CGM devices, requiring implantation or the use of hypodermic needles, fail to offer a convenient solution. We have demonstrated that magnetohydrodynamics (MHD) is effective at extracting dermal interstitial fluid (ISF) containing glucose, without the use of needles. Here we present the first study of ISF sampling with MHD for glucose monitoring in humans. We conducted 10 glucose tolerance tests on 5 healthy volunteers and obtained a significant correlation between the concentration of glucose in ISF samples extracted with MHD and capillary blood glucose samples. Upon calibration and time lag removal, the data indicate a Mean Absolute Relative Difference (MARD) of 12.9% and Precision Absolute Relative Difference of 13.1%. In view of these results, we discuss the potential value and limitations of MHD in needle-free glucose monitoring.

A systematic review was carried out to synthesize data on the efficacy and safety of the treatment of coronavirus disease-19 in the pediatric population.

Evidence suggests that Collectivism in cultures influence a society’s behavior on goals and rules. Therefore, we wanted to observe if there’s and effect of individualism and collectivism in how people perceive and follow social distancing recommendations.

A discrete space-time structure lying at about the Planck scale may become manifest in the form of very small violations of the conservation of the matter energy-momentum tensor. In order to include such kind of violations, forbidden within the General Relativity framework, the theory of unimodular gravity seems as the simplest option to describe the gravitational interaction. In the cosmological context, a direct consequence of such violation of energy conservation might be heuristically viewed a "diffusion process of matter (both dark and ordinary)" into an effective dark energy term in Einstein's equations, which leads under natural assumptions to an adequate estimate for the value of the cosmological constant. Previous works have also indicated that these kind of models might offer a natural scenario to alleviate the Hubble tension. In this work, we consider a simple model for thecosmological history including a late time occurrence of such energy violation and study the modifications of the predictions for the anisotropy and polarization of the Cosmic Microwave Background (CMB). We compare the model's predictions with recent data from the CMB, Supernovae Type Ia, cosmic chronometers and Baryon Acoustic Oscillations. The results show the potential of this type of model to alleviate the Hubble tension., Comment: 17 pages, 4 figures

El agua es uno de los recursos más preciados del ser humano, dado que, sin agua, la vida no sería posible. Por ello, cuesta entender que se le dé un mal uso, se malgaste, no se reutilice o se contamine. En el presente proyecto, se pretende desarrollar un método accesible que permita reutilizar gran cantidad de agua, la cual se realiza sometiendo a aguas a las que ya se les ha dado un uso a tratamientos; para afrontar ciertas tareas en la vivienda con el agua ya tratada, lo que conlleva un ahorro en recursos hídricos. El proceso consiste en captar tanto aguas pluviales como grises, procediendo estas últimas de lavadoras, lavabos, duchas, lavavajillas y fregaderos de una vivienda unifamiliar localizada en el municipio de Arnuero, Cantabria. Estas, son sometidas a un tratamiento que combina tratamiento primario, aireación y extracción de agua depurada, alcanzándose la calidad mínima requerida por el RD 1620/2007, por el que se establece el Régimen Jurídico de la Utilización de Aguas Depuradas para dos usos concretos a los que se ha decidido destinar: recarga de inodoros y riego de jardines. Este proceso es posible gracias a la instalación de un sistema de saneamiento que permite la recogida desde la cubierta y los puntos de consumo antes mencionados, y a través de colectores (tuberías enterradas) se envían al equipo de tratamiento. Una vez tratadas, un equipo de bombeo posibilita el retorno para la reutilización de aguas. La duración de obra prevista será de 21 días, y el equipo con el que se contará será de 3 trabajadores, que realizarán las tareas requeridas en una jornada laboral de lunes a viernes durante 8 horas diarias. Se ha estipulado que las obras comiencen el día 6 de abril de 2021. El presupuesto de Ejecución por Contrata asciende a 16.641,46 euros. De este modo, la realización de este proyecto resultará en varias ventajas. Por un lado, el ahorro económico a lo largo de los años será evidente, y al mismo tiempo, se colaborará en la lucha para poder alcanzar un desarrollo sostenible. Water is one of the most valued resources for the humans, because, without water, life wouldn ́t be possible in the Earth. Therefore, it ́s difficult to explain why the humans misuse, don ́t re-use, or pollute it. In this project, it is intended to develop an accessible method that allows to reuse a large amount of water, which is carried out by subjecting water that has already been used to treatments; to face certain tasks with the treated water, which results in saving water resources. The process consists of capturing both rainwater and gray water, coming the latter from washing machines, sinks, showers and dishwashers of a single-family home located in the village of Arnuero, Cantabria. These, are subjected to a combine of a primary treatment, aeration and extraction of purified water, reaching the minimum quality required by R.D: 1620/2007, which establishes the Legal Regime for the Use of Purified Water for two specific uses: recharging toilets and watering gardens. This process is possible thanks to an installation of a sanitation network that allows a rainwater and gray water collection, which is sent to the treatment equipment through the collectors. Once the water is treated, a pumping equipment enables the return of the water to the reuse points. The planned duration of the work will be 21 days, and the working team will be counted on 3 workers, who will carry out the required tasks from Monday to Friday, for 8 hours a day. It has been stipulated that the works will begin on April 6, 2021. The forecasted budget is 16.641,46 euros. This project will result in several advantages. On the one hand, the economic savings over the years will be evident; and, on the other hand, it will be a gun to collaborate in the fight to achieve sustainable development. Ura gizakiaren baliabiderik preziatuenetako bat da, izan ere, urik gabe, bizitza ez litzateke posible izango. Hori dela eta, ulertezina da urari erabilera okerra ematea, xahutzea, ez berrerabiltzea edo kutsatzea. Proiektu honetan, ur kopuru handia berrerabiltzeko aukera ematen duen metodo eskuragarria garatu nahi da, lehendik erabilitako urak tratatuz gero, etxeko zeregin batzuei aurre egiteko eta horrek ur baliabideetan aurrezteko. Prozesua euri ura eta ur grisak harrapatzean datza, azken hauek garbigailuetatik, konketetatik, dutxetatik, eta Kantabriako Arnuero udalerrian kokatutako familia bakarreko etxebizitzako ontzi garbigailuetatik datoz. Urak aireztapena eta erauzketa konbinatzen dituen tratamendu bat jasaten dute, 1620/2007 EDak eskatzen duen gutxieneko kalitatea lortuz, ur araztua erabiltzeko araubide juridikoa ezartzen duen bi erabilera zehatzetarako eta erabaki direnetarako: komunak kargatzea eta lorategiak ureztatzea. Prozesu hau teilatuetatik eta aipatutako kontsumo puntuetatik biltzea ahalbidetzen duen saneamendu sistema instalatzeari esker lortzen da eta kolektoreen bidez (lurperatutako hoditeriak) tratamendu ekipoetara bidaltzen dira. Tratatu ondoren, ponpaketa ekipo batek ura berrerabiltzeko aukera ematen du. Lanaren iraupena 21 egunekoa izango da, eta lan taldea 3 langilez osatuko da, astelehenetik ostiralera eguneko 8 orduz lanegunean eskatutako lanak burutuko dituztenak. Lanak 2021eko apirilaren 6an hasten direla zehaztu da. Kontratu bidez gauzatzeko aurrekontua 16.641,46 eurokoa da. Horrela, proiektu hau aurrera eramateak hainbat abantaila ekarriko ditu. Batetik, urtetako aurrezki ekonomikoa agerikoa izango da, eta, aldi berean, garapen iraunkorra lortzeko borrokan parte hartuko dugu.

This paper describes how the concept of virtual engineering can be applied to the factory planning process. Our journey starts with the definition of what virtual engineering is, its pillars and what benefits this concept brings with respect to the traditional concepts of design used today. It is followed by our definition of what is considered a working environment and the boundaries of the physical-virtual world, and it ends with the applications of virtual and augmented reality technologies in the factory-layout planning process.

We present an overall picture of the advances in the description of black hole physics from the perspective of loop quantum gravity. After an introduction that discusses the main conceptual issues we present some details about the classical and quantum geometry of isolated horizons and their quantum geometry and then use this scheme to give a natural definition of the entropy of black holes. The entropy computations can be neatly expressed in the form of combinatorial problems solvable with the help of methods based on number theory and the use of generating functions. The recovery of the Bekenstein-Hawking law and corrections to it is explained in some detail. After this, due attention is paid to the discussion of semiclassical issues. An important point in this respect is the proper interpretation of the horizon area as the energy that should appear in the statistical-mechanical treatment of the black hole model presented here. The chapter ends with a comparison between the microscopic and semiclassical approaches to the computation of the entropy and discusses a number of issues regarding the relation between entanglement and statistical entropy and the possibility of comparing the subdominant (logarithmic) corrections to the entropy obtained with the help of the Euclidean path integral with the ones obtained in the present framework.

Ejercicio de TFM que aborda el diseño de una escuela de jardinería y agricultura en la huerta de Las Fuentes en Zaragoza. Plantea un interesante reto desde el punto de vista paisajístico por su relación con un entorno natural de alto nivel cultural para la ciudad y sus habitantes. El proyecto aborda a dos escalas diferentes la relación con el paisaje, tanto con los cultivos cercanos inmediatos como con los grandes espacios naturales de la ribera de los ríos Ebro y Gállego

In this letter, we consider the possibility of reconciling metric theories of gravitation with violation of the conservation of energy-momentum. Under some circumstances, this can be achieved in the context of unimodular gravity, and it leads to the emergence of an effective cosmological constant in Einstein's equation. We specifically investigate two potential sources of energy non-conservation ---non-unitary modifications of quantum mechanics, and phenomenological models motivated by quantum gravity theories with spacetime discreteness at the Planck scale--- and show that such locally negligible phenomena can nevertheless become relevant at the cosmological scale., Comment: 6 pages, 1 figure, to appear in Physical Review Letters

Loss of the tumour suppressor PTEN is frequent in human melanoma, results in MAPK activation, suppresses senescence and mediates metastatic behaviour. How PTEN loss mediates these effects is unknown. Here we show that loss of PTEN in epithelial and melanocytic cell lines induces the nuclear localization and transcriptional activation of β-catenin independent of the PI3K-AKT-GSK3β axis. The absence of PTEN leads to caveolin-1 (CAV1)-dependent β-catenin transcriptional modulation in vitro, cooperates with NRAS(Q61K) to initiate melanomagenesis in vivo and induces efficient metastasis formation associated with E-cadherin internalization. The CAV1-β-catenin axis is mediated by a feedback loop in which β-catenin represses transcription of miR-199a-5p and miR-203, which suppress the levels of CAV1 mRNA in melanoma cells. These data reveal a mechanism by which loss of PTEN increases CAV1-mediated dissociation of β-catenin from membranous E-cadherin, which may promote senescence bypass and metastasis.

Objetivo: Describir la implantación de un robot para la elaboración de antineoplásicos en el Servicio de Farmacia y evaluar el valor añadido al proceso farmacoterapéutico. Método: La implantación se llevó a cabo en Junio 2012 en un hospital de tercer nivel, realizándose en dos períodos: 1-Período de pruebas con la instalación del robot, configuración técnica del equipo, validación de 29 principios activos e integración con el software de prescripción electrónica (9 meses); 2-Período de utilización (22 meses). Se impartieron cursos de formación a farmacéuticos y personal de enfermería. Para su funcionamiento el robot emplea reconocimiento fotográfico, identificación por código de barras y controles gravimétricos, que proporcionaron datos de error cometido por preparación, tolerando ±10% y restringiéndolo, tras un estudio piloto, a un intervalo de tolerancia de ±4%. El robot fue programado para reconocer bolsas, infusores, jeringas y viales. El valor añadido se evaluó durante 31 meses con la identificación de los errores de preparación. Resultados: Se realizaron 1 1.865 preparaciones en el robot, que correspondieron al 40% del global de antineoplásicos elaborados, de 29 principios activos diferentes. Se identificaron y evitaron errores de dosificación en el 1,12% (n=133) de las preparaciones, que no alcanzaron al paciente al ser identificadas por el robot como preparaciones con desviación negativa (-4%) y ser corregidas manualmente. Conclusiones: La implantación de un robot en la elaboración de antineoplásicos permite identificar los errores de elaboración y evitar que lleguen al paciente, promoviendo la seguridad y calidad del proceso farmacoterapéutico de antineoplásicos y reduciendo la exposición del manipulador a los mismos.

CP-violation (CPV) and Time-reversal violation (TRV) are intimately related through the CPT theorem: if one of these discrete symmetries is violated the other one has to be violated in such a way to conserve CPT. Although CPV in the B0-B0 system has been established by the B-factories, implying indirectly TRV, there is still no direct evidence of TRV. We report on the observation of TRV in the B-meson system performed with a dataset of 468 million BB pairs produced in Y(4S) decays collected by the BABAR detector at the PEP-II asymmetric-energy e+e- collider at the SLAC National Accelerator Laboratory. We also report on other CPV measurements recently performed on the B-meson system., Comment: 7 pages, 3 figures

The comment arXiv:1204.2729v1 is completely wrong. The author makes serious mistakes in calculations and judgement. The errors are made at the level of basic undergraduate statistical mechanics.

The study of rare B-decays at SuperB provides unique opportunities to understand the Standard Model and constrain new physics. It is discussed the new physics potential of the B -> K nu nu_bar and B -> K^{\ast} nu nu_bar system from the proposed SuperB experiment with 75ab-1 of data (5 nominal years of data taking)., 3 pages, 3 figures, proceedings for 35th International Conference of High Energy Physics - ICHEP2010

The Immirzi parameter is a constant appearing in the general relativity action used as a starting point for the loop quantization of gravity. The parameter is commonly believed not to show up in the equations of motion, because it appears in front of a term in the action that vanishes on shell. We show that in the presence of fermions, instead, the Immirzi term in the action does not vanish on shell, and the Immirzi parameter does appear in the equations of motion. It determines the coupling constant of a four-fermion interaction. Therefore the Immirzi parameter leads to effects that are observable in principle, even independently from nonperturbative quantum gravity., Comment: 3 pages. Substantial revision from the first version

These notes are a didactic overview of the non perturbative and background independent approach to a quantum theory of gravity known as loop quantum gravity. The definition of real connection variables for general relativity, used as a starting point in the program, is described in a simple manner. The main ideas leading to the definition of the quantum theory are naturally introduced and the basic mathematics involved is described. The main predictions of the theory such as the discovery of Planck scale discreteness of geometry and the computation of black hole entropy are reviewed. The quantization and solution of the constraints is explained by drawing analogies with simpler systems. Difficulties associated with the quantization of the scalar constraint are discussed.In a second part of the notes, the basic ideas behind the spin foam approach are presented in detail for the simple solvable case of 2+1 gravity. Some results and ideas for four dimensional spin foams are reviewed., Comment: Lectures presented at the II International Conference of Fundamental Interactions, Pedra Azul, Brazil, June 2004. Typos corrected

We examine radiative corrections arising from Lorentz violating dimension five operators presumably associated with Planck scale physics as recently considered by Myers and Pospelov. We find that observational data result in bounds on the dimensionless parameters of the order $10^{-15}$. These represent the most stringent bounds on Lorentz violation to date.

The CDW Hartree-Fock state at half filling and half electron per unit cell is examined. Firstly, an exact solution in terms of Bloch-like states is presented. Using this solution we discuss the dynamics near half filling and show the mass to diverge logarithmically as this filling is approached. We also show how a uniform density state may be constructed from a linear combination of two degenerate solutions. Finally we show the second order correction to the energy to be an order of magnitude larger than that for competing CDW solutions with one electron per unit cell., Comment: 14 pages, no figures, extended acknowledgements, two new references included

We study a family of physical observable quantities in quantum gravity. We denote them W functions, or n-net functions. They represent transition amplitudes between quantum states of the geometry, are analogous to the n-point functions in quantum field theory, but depend on spin networks with n connected components. In particular, they include the three-geometry to three-geometry transition amplitude. The W functions are scalar under four-dimensional diffeomorphism, and fully gauge invariant. They capture the physical content of the quantum gravitational theory. We show that W functions are the natural n-point functions of the field theoretical formulation of the gravitational spin foam models. They can be computed from a perturbation expansion, which can be interpreted as a sum-over-four-geometries. Therefore the W functions bridge between the canonical (loop) and the covariant (spinfoam) formulations of quantum gravity. Following Wightman, the physical Hilbert space of the theory can be reconstructed from the W functions, if a suitable positivity condition is satisfied. We compute explicitly the W functions in a "free" model in which the interaction giving the gravitational vertex is shut off, and we show that, in this simple case, we have positivity, the physical Hilbert space of the theory can be constructed explicitly and the theory admits a well defined interpretation in terms of diffeomorphism invariant transition amplitudes between quantized geometries., Comment: 25 pages, typos corected

We study the Hamiltonian formulation of the general first order action of general relativity compatible with local Lorentz invariance and background independence. The most general simplectic structure (compatible with diffeomorphism invariance and local Lorentz transformations) is obtained by adding to the Holst action the Pontriagin, Euler and Nieh-Yan invariants with independent coupling constants. We perform a detailed canonical analysis of this general formulation (in the time gauge) exploring the structure of the phase space in terms of connection variables. We explain the relationship of these topological terms, and the effect of large SU(2) gauge transformations in quantum theories of gravity defined in terms of the Ashtekar-Barbero connection.

The precise analog of the theta-quantization ambiguity of Yang-Mills theory exists for the real SU(2) connection formulation of general relativity. As in the former case theta labels representations of large gauge transformations, which are super-selection sectors in loop quantum gravity. We show that unless theta=0, the (kinematical) geometric operators such as area and volume are not well defined on spin network states. More precisely the intersection of their domain with the dense set Cyl in the kinematical Hilbert space H of loop quantum gravity is empty. The absence of a well defined notion of area operator acting on spin network states seems at first in conflict with the expected finite black hole entropy. However, we show that the black hole (isolated) horizon area--which in contrast to kinematical area is a (Dirac) physical observable--is indeed well defined, and quantized so that the black hole entropy is proportional to the area. The effect of theta is negligible in the semiclassical limit where proportionality to area holds.

We show that the quantization ambiguities of loop quantum cosmology, when considered in wider generality, can be used to produce discretionary dynamical behavior. There is an infinite dimensional space of ambiguities which parallels the infinite list of higher curvature corrections in perturbative quantum gravity. There is however an ensemble of qualitative consequences which are generic in the sense that they are independent of these ambiguities. Among these, one has well defined fundamental dynamics across the big bang, and the existence of extra microscopic quantum degrees of freedom that might be relevant in discussions about unitarity in quantum gravity. We show that (in addition to the well known bouncing solutions of the effective equations) there are other generic type of solutions for sufficiently soft initial conditions in the matter sector (tunneling solutions) where the scale factor goes through zero and the spacetime orientation is inverted. We also show that generically, a contracting semiclassical universe branches off at the big bang into a quantum superposition of universes with different quantum numbers. Despite their lack of quantitative predictive power these models offer a fertile playground for the discussion of qualitative and conceptual issues in quantum gravity.

Since 1916 intriguing questions have arisen from the study of Black Holes (BH). Only some of them have been resolved. Indeed, we are faced with regimes where the yet unknown interplay between quantum theory and spacetime unveils. BH physics is a gateway to the quantum nature of gravity. My thesis has been completely devoted to this central domain of theoretical physics, with the guiding aim of understanding in the widest possible manner the debate around those questions. The process has produced original results that constitute the main core of the manuscript. 1- The maximal volume surfaces of evaporating BHs are studied. An astrophysical BH will end its life with an external planckian area 10⁻⁷⁰ m² hiding 10⁵ times the volume of our observable Universe. This can have consequences on the viability of the “remnant scenario” as solution to the BH information paradox. 2- The “black-hole-to-white-hole scenario” is analyzed. The model is shown to be strongly unstable, and a minimal resolutive modification is proposed. 3- A generalisation of the four laws of BH thermodynamics is proven for intersecting light cones in Minkowski spacetime. 4- Conformally flat spaces where such laws acquire the standard thermodynamical interpretation are studied. The simplest one is the Bertotti-Robinson spacetime, known to encode the near-horizon geometry of a charged BH. 5- It is shown that, if the correct energy-momentum tensor is identified, the Eintein-Cartan’s field equations can be recovered as a thermodynamical equilibrium equation of state just like in the GR original case. Such results contribute to the intense debate on the opening crucial questions., Depuis 1916, l'étude des Trous Noirs a soulevé des questions intrigantes. Seulement certaines ont été résolues. En effet, nous faisons face à des régimes où s’entremêlent la théorie quantique et l'espace-temps. Les TN comme porte d'entrée pour comprendre la nature quantique de la gravité. Ma thèse a été entièrement dédiée à ce domaine central de la physique théorique, avec pour but la compréhension la plus large possible des débats autour de ces questions. C'est ainsi qu'ont été produits des résultats originaux qui constituent le cœur de ce manuscrit. 1-Les surfaces de volume maximal des TN sont étudiées. Un TN astrophysique terminera sa vie avec une aire planckienne de 10⁻⁷⁰ m² dissimulant 10⁵ fois le volume de l'univers observable. Ceci peut avoir des conséquences sur la viabilité du "remnant scenario" comme solution au paradoxe de l'information. 2-Le scénario "trou-noir-trou-blanc" est fortement instable. Une modification minimale est proposée pour résoudre ce problème. 3-Une généralisation des quatre lois de la thermodynamique des TN est démontrée pour des cônes de lumière s'intersectant dans un espace de Minkowski. 4-On étudie des espaces conformellement plats où de telles lois acquièrent une interprétation thermodynamique standard. Le plus simple est l'espace-temps de Bertotti-Robinson, connu pour encoder la géométrie proche de l'horizon d'un TN chargé. 5-Pour peu que le bon tenseur énergie-impulsion soit identifié, les équations du champ Einstein-Cartan peuvent être retrouvées comme l'équation d'état d'un équilibre thermodynamique, comme dans le cas original de la RG. Ces résultats contribuent au débat intense sur les questions cruciales posées ci-dessus.