Quantum walks: a comprehensive review

Quantum walks, the quantum mechanical counterpart of classical random walks, is an advanced tool for building quantum algorithms that has been recently shown to constitute a universal model of quantum computation. Quantum walks is now a solid field of research of quantum computation full of exciting open problems for physicists, computer scientists, mathematicians and engineers. In this paper we review theoretical advances on the foundations of both discrete- and continuous-time quantum walks, together with the role that randomness plays in quantum walks, the connections between the mathematical models of coined discrete quantum walks and continuous quantum walks, the quantumness of quantum walks, a summary of papers published on discrete quantum walks and entanglement as well as a succinct review of experimental proposals and realizations of discrete-time quantum walks. Furthermore, we have reviewed several algorithms based on both discrete- and continuous-time quantum walks as well as a most important result: the computational universality of both continuous- and discrete- time quantum walks.Comment: Paper accepted for publication in Quantum Information Processing Journa

Incidence, typology and measures of prevention and treatment of skin lesions associated with the use of personal protective equipment in health care professionals during the COVID-19 pandemic in Spain

Introducción: La reciente pandemia de COVID-19 ha representado la utilización por parte de los profesionales de la salud de diferentes equipos de protección individual (EPI), lo que ha dado lugar a la aparición de lesiones cutáneas asociadas a los mismos (LC-EPI). Conocer la epidemiología, las características y los factores relacionados con el uso de los diferentes tipos de EPI y la prevención y el tratamiento de las LC-EPI puede ser muy útil para comprender el alcance del problema y definir estrategias para su prevención y tratamiento en posibles pandemias futuras. Métodos: Estudio transversal realizado por el Grupo Nacional para el Estudio y Asesoramiento en Úlceras por Presión y Heridas Crónicas (GNEAUPP) en el ámbito geográfico del Estado español, mediante una encuesta autoadministrada utilizando un cuestionario de Google Forms. El universo de estudio fueron profesionales de la salud, de cualquier disciplina y nivel asistencial o tipo de institución que habían estado en contacto con pacientes o sospechosos de COVID-19 y habían utilizado EPI durante la primera ola de la pandemia de COVID-19 en España. Resultados: Se obtuvieron 2078 cuestionarios, el 75,5% de enfermeras, el 10,79% de técnicos en cuidados auxiliares de enfermería (TCAE) y el 6,6% de médicos. De los respondedores, el 84,7% eran mujeres y el 15,3% hombres con una edad media de 43,7 años. En el 18,2% de los casos, la institución del profesional contaba con un protocolo para la prevención de las LC-EPI, en el 10,2% el profesional no sabía si existía y en el 71,3% restante la institución no contaba con dicho protocolo. El 29,9% de los profesionales utilizaba siempre algún producto de prevención de LC-EPI y el 25,3% en ocasiones. El 52,4% de los encuestados informó haber presentado al menos una LC-EPI, de los cuales el 39% había presentado una, el 35,8% dos, el 14,3% tres, el 2,2% cuatro y el 8,6% más de cuatro. En relación con el tipo de lesiones, el 74,3% fueron definidas como lesiones por presión (LPP), el 11% como lesiones por fricción (LF), el 8,5% como lesiones combinadas o multicausales (LCMC) y el 6,1% como lesiones cutáneas asociadas a la humedad (LESCAH). La duración media de las lesiones incidentes fue de 11,6 días (9,7 días para las LPP, 10,2 días para las LF, 19,9 días para las LCMC y 19,4 días para las LESCAH). En el artículo se presenta información más detallada por tipo de dispositivo causante, tipología y gravedad de las lesiones por dispositivo, así como las medidas preventivas utilizadas.Introduction: The recent COVID-19 pandemic has represented the use by health care professionals (HCP) of different personal protective equipment (PPE), resulting in the appearance of skin injuries associated with PPE (PPE-SI). Knowing the epidemiology, characteristics and factors related to the use of different types of PPE and the prevention and treatment of PPE-SI can be very useful to understand the scope of the problem and to define strategies for its prevention and treatment in possible future pandemics. Methods: To this end, the GNEAUPP proposed the performance of a cross-sectional study, in the geographical area of the Spanish state, by means of a self-administered survey using a Google forms questionnaire. The study universe was HCP, from any discipline and from any level of care or type of institution with patients who have been in contact with COVID-19 patients or COVID-19 suspects and have used PPE during the first wave of the COVID-19 pandemic in Spain. Main results: We obtained 2078 questionnaires, 75.5% from nurses, 10.79% from nurse aids, and 6.6% from physicians. Of these, 84.7% were women and 15.3% were men with an average age of 43.7 years. In 18.2% of the cases the institution of the professional had a protocol for the prevention of PPE-SI, in 10.2% the professional did not know if it existed or not and in the remaining 71.3% the institution did not have such a protocol. 29.9% of the professionals always used some prevention product and 25.3% sometimes. 52.4% of respondents reported having submitted at least one PPE-SI, of which 39% had submitted one, 35.8% two, 14.3% three, 2.2% four and 8.6% more than four. In relation to PPE-SI, 74.3% were defined as pressure injuries (PI), 11% were friction injuries (FI), 8.5% were combined or multicausal injuries (CMCI) and 6.1% were skin injuries associated with moisture (MASI). The mean duration of incident injuries was 11.6 days (9.7 days for PI, 10.2 days for FI, 19.9 days for CMCI and 19.4 days for MASI). More detailed Information is presented in the paper by type of device causing, typology and severity of injuries per device as well as preventive measures used

Innovation capability and its role in enhancing the relationship between TQM practices and innovation performance

Innovation plays a critical role in predicting the long-term survival of organizations, determining an organization’s success and sustaining its global competitiveness, especially in an environment where technologies, competitive position and customer demands can change almost overnight, and where the life-cycle of products and services are becoming shorter.Therefore, the main purpose of this paper is to extend the existing knowledge as to the relationship between TQM practices and innovation performance by exploring the expected role of innovation capability as mediator to enhance this relationship.At the same time, this study attempted to shed a light on how to improve innovation performance of manufacturing companies in Malaysia.The gained results indicated that innovation capability mediates the relationship between TQM practices and innovation performance. More importantly, this study supports the findings of the past studies that questioned the role of TQM practices in improving innovation performance. Finally, in light of the obtained results, several recommendations were introduced to assist decision makers in manufacturing companies

Evaluation of host-guest complex formation between a benzimidazolic derivative and cyclodextrins by UV-VIS spectrophotometry and differential scanning calorimetry

Abstract Interactions between a benzimidazolic derivative, omeprazole (OME), beta-cyclodextrin (ßCD) and a chemically modified ßCD, methyl-beta-cyclodextrin (MßCD) were investigated in aqueous solution by UV-VIS spectroscopy and in solid state by differential scanning calorimetry (DSC). Phase solubility studies were used to evaluate the complexation in aqueous solution. The two solubility diagrams obtained were AL type, indicating the formation of a drug-cyclodextrin complex with 1:1 stoichiometry. The complex of OME with MßCD showed a higher stability constant (K S) than those with ßCD. Some evidences of inclusion complexation in solid state were obtained from DSC. Only in thermal curves of OME-ßCD lyophilized product and in OME-MßCD spray-dried and lyophilized systems the melting point of the drug disappeared completely suggesting the possible formation of an inclusion complex

Small extracellular vesicle-mediated targeting of hypothalamic AMPKα1 corrects obesity through BAT activation.

Current pharmacological therapies for treating obesity are of limited efficacy. Genetic ablation or loss of function of AMP-activated protein kinase alpha 1 (AMPKα1) in steroidogenic factor 1 (SF1) neurons of the ventromedial nucleus of the hypothalamus (VMH) induces feeding-independent resistance to obesity due to sympathetic activation of brown adipose tissue (BAT) thermogenesis. Here, we show that body weight of obese mice can be reduced by intravenous injection of small extracellular vesicles (sEVs) delivering a plasmid encoding an AMPKα1 dominant negative mutant (AMPKα1-DN) targeted to VMH-SF1 neurons. The beneficial effect of SF1-AMPKα1-DN-loaded sEVs is feeding-independent and involves sympathetic nerve activation and increased UCP1-dependent thermogenesis in BAT. Our results underscore the potential of sEVs to specifically target AMPK in hypothalamic neurons and introduce a broader strategy to manipulate body weight and reduce obesity