An equation of state for purely kinetic k-essence inspired by cosmic topological defects

We investigate the physical properties of a purely kinetic k-essence model with an equation of state motivated in superconducting membranes. We compute the equation of state parameter $w$ and discuss its physical evolution via a nonlinear equation of state. Using the adiabatic speed of sound and energy density, we restrict the range of parameters of the model in order to have an acceptable physical behavior. Furthermore, we analyze the evolution of the luminosity distance $d_{L}$ with redshift $z$ by comparing (normalizing) it with the $\Lambda$CDM model. Since the equation of state parameter is $z$-dependent the evolution of the luminosity distance is also analyzed using the Alcock-Paczy\'{n}ski test.Comment: 19 pages, 13 figures, typos corrected and references adde

A possible cosmological application of some thermodynamic properties of the black body radiation in n−n-dimensional Euclidean spaces

In this work we present the generalization of some thermodynamic properties of the black body radiation (BBR) towards an $n-$dimensional Euclidean space. For this case the Planck function and the Stefan-Boltzmann law have already been given by Landsberg and de Vos and some adjustments by Menon and Agrawal. However, since then no much more has been done on this subject and we believe there are some relevant aspects yet to explore. In addition to the results previously found we calculate the thermodynamic potentials, the efficiency of the Carnot engine, the law for adiabatic processes and the heat capacity at constant volume. There is a region at which an interesting behavior of the thermodynamic potentials arise, maxima and minima appear for the $n-d$ BBR system at very high temperatures and low dimensionality, suggesting a possible application to cosmology. Finally we propose that an optimality criterion in a thermodynamic framework could have to do with the $3-d$ nature of the universe.Comment: 9 pages, 8 figure

en la mediana empresa Unión de Cooperativas de Cafés especiales Cordillera Isabelia R.L (U.C.C.E.I) del Municipio de Matagalpa, en el I semestre del año 2011

La evaluación del sistemacontable y de los procedimientos de Control Interno Administrativos y Financieros en La Unión de Cooperativas de Cafés Especiales Cordillera Isabelia R.L (UCCEI) del municipio de Matagalpa tiene el propósito de comprender de manera especifica el uso y aplicación de tales procedimientos de control al momento de ejecutar las operaciones de la entidad, así como también entender el manejo del registro del sistema contable que se utiliza con el fin de obtener una información financiera objetiva a través de la eficacia de las operaciones. El tema en estudio es de gran importancia ya que nos brinda una visión clara y precisa de las debilidades que día a día se pasan por alto en el transcurso del ejercicio económico, así como también los riesgos a que está expuesta la cooperativa y su manejo para evitar errores de magnitud que puedan afectar los estados financieros y su presentación. El buen funcionamiento de una entidad radica en la aplicación eficiente del control interno, además del uso eficaz de los sistemas contables. En UCCEI existen riesgos inherentes en las operaciones y en el registro adecuado de las transacciones las cuales deben su origen en la poca capacitación del personal fijo que labora en las instalaciones, además de esto el manual de control interno no se actualiza y solamente lo tiene el área de contabilidad; existe un organigrama que especifica las unidades que operan en la entidad, sin embargo, no es funcional ya que el área administrativa ejerce las labores en casi todos los puestos debido a que no hay personal para laborar en las distintas unidade

Acute phase markers in obese children and adolescents with metabolic disorders

ABSTRACT Introduction. Obesity is a worldwide public health problem and the most common non-communicable chronic disease. It is associated with an increase in inflammatory acute phase proteins and proinflammatory cytokines. Objective. To assess the levels of acute phase proteins in obese children and adolescents with hepatic steatosis and metabolic syndrome. Methodology. Forty-five children with a body mass index ≥ 95th percentile aged 5.0-15.5 years were included. The following acute phase reactants were determined: C-reactive protein, haptoglobin, alpha-2-macroglobulin, and apolipoprotein A-1; besides, an ultrasound was done to assess hepatic steatosis. Results. C-reactive protein levels increased in all patients. Patients with metabolic syndrome also had high levels of apolipoprotein A-1 and haptoglobin. Patients with hepatic steatosis had a significant increase in alpha-2-macroglobulin in addition to high C-reactive protein. Key words: obesity, C-reactive protein, haptoglobins, alpha-2macroglobulins, apolipoprotein A-1

Revisión histórica de la formación continua a distancia para profesores en México

En México, cada gobierno ha configurado diferentes estrategias para proveer formación continua a los maestros, con base en las necesidades educativas identificadas, el perfil docente deseable y los recursos tecnológicos con los que dispone durante su gestión. Aunque la modalidad educativa a distancia ha representado parte importante de los esfuerzos para proveer formación continua a los maestros en México, esta ha sido poco documentada y estudiada. Es por ello, que el presente artículo tiene como propósito describir la forma en que se ha desarrollado la oferta de formación continua a distancia para docentes en servicio de educación básica en México, propuesta por el Estado desde 1944 hasta 2018. A través de este recuento, es posible identificar un avance paralelo entre los propósitos de la formación continua y los recursos tecnológicos empleados. Las necesidades de formación continua de los docentes se complejizaron a medida que se elevó el grado de estudio del magisterio. En relación al avance tecnológico, se ha desarrollado una oferta cada vez más sofisticada, la cual pasó del empleo de medios impresos hasta la creación de ambientes virtuales de aprendizaje

Phase transition at 350 K in the Ti3_3C2_2Tx_x MXene: possible sliding (moir\'e) ferroelectricity

A phase transition is found in Ti$_3$C$_2$T$_x$ MXene at 350 K, by measuring the complex Young's modulus of self-standing thick films. A step-like softening and increase of the mechanical losses is found below 350 K, indicative of a phase transition, where the square of the order parameter is coupled to strain. It is argued that it should be a ferroelectric transition, most likely of the sliding (moir\'e) type, due to charge transfer between facing flakes sliding with respect to each other. If the transition will be confirmed to be ferroelectric, Ti$_3$C$_2$T$_x$ will be added to the class of metallic ferroelectrics and open new perspectives of applications, in addition to the numerous already studied

Tuberculosis en trabajadores de los establecimientos de salud de la Región Callao : Tuberculosis among workers of health facilities in the Callao Region

Objective: To determine the characteristics of tuberculosis in the health personnel of the establishments of the Callao Region.Materials and methods. The study was cross-sectional descriptive. All health personnel who had tuberculosis while working in health facilities in the period 2013 to 2015 constituted the study population. Of 48 registered, 41 met the study criteria.Results. Of the total sample, 43.9% (n = 18) were nursing technicians, followed by nursing and administrative personnel. More than 90% of those affected had a hospital as a work center, 65.9% (n = 27) had pulmonary tuberculosis, 46.3% (n = 19) reported closed space, 34.1% (n = 14) with the presence of overcrowding. Regarding the use of N95 respirators, 46.3% (n = 19) did not use it, while 31.7% (n = 13) used it sporadically. Respect for the harmful habits of health workers, 61% (n = 25) showed consumption habits of alcohol and 36.6% (n = 15) for tobacco. Among the comorbidities present in health workers with tuberculosis, diabetes mellitus and depression stand out, in 34.1% (n = 14) and 17.1% (n = 7) respectively. Conclusions. Tuberculosis in health personnel affects mainly the technical nursing staff working in hospital establishments. A high percentage of health personnel with non-compliance with the protection measures was found. Keywords: Tuberculosis, Health Personnel, Healthcare Workers, Health Facilities, Peru (Source: MeSH, NLM)Objetivo. Determinar las características de la tuberculosis en el personal de salud de los establecimientos de salud de la Región Callao. Materiales y métodos.  El estudio fue descriptivo, y transversal. La población de estudio estuvo constituida por todo el personal de salud que tuvo tuberculosis mientras laboraban en los establecimientos de salud en el periodo 2013 a 2015. De 48 registrados, 41 cumplieron con los criterios del estudio. Resultados. El 43,9% (n=18) eran técnicos en enfermería, seguido por el personal de enfermería y administrativos. Más del 90% de los afectados tenían como centro de trabajo un establecimiento hospitalario.  El 65,9% (n=27) tuvieron tuberculosis pulmonar. El 46,3% (n=19) refirieron espacio cerrado, el 34,1% (n=14) con presencia de hacinamiento. Respecto al uso de respiradores N95, el 46,3% (n=19) no usaron, mientras que el 31,7% (n=13) lo usaron de manera esporádica.  Respeto a los hábitos nocivos de los trabajadores de salud, el 61% (n=25) mostraron hábitos de consumo de alcohol y el 36,6%(n=15) por el tabaco. Entre las comorbilidades presentes en los trabajadores de salud con tuberculosis, destacan la diabetes mellitus y la depresión, en el 34,1%(n=14) y el 17,1% (n=7) respectivamente. Conclusiones. La tuberculosis en el personal de salud afecta principalmente al personal técnico de enfermería que laboran en establecimientos hospitalarios. Se encontró un alto porcentaje del personal de salud con incumplimiento de las medidas de protección. Palabras Clave: Tuberculosis, personal de salud, trabajadores de la salud, establecimientos de salud, Perú (Fuente: DeCS, BIREME)  

PBL based on chemistry laboratories at engineering degree

Until now, the didactics used in the teaching of experimental chemistry contradicts its objective by continuing with a traditional approach and with passive didactic methods for students. Even, in virtual environments, working in the laboratory practices is basically "following a recipe" where the student does not have the opportunity to ask, make decisions or apply to their daily life. In addition to this, it happens that the "recipes" of the laboratories, in general, are repeated frequently, sometimes semester after semester. The recipes have been tested, being known to give good results, and offer no major difficulties, but the recipes do not present uncertainty for the student. On the other hand, we find the problem of the use of ICT in laboratories, which needs a change of focus. It also requires a change of environment, it is convenient to incorporate measurement processes, analyze data in real time and treat what is observed It should be remembered that Chemistry is an experimental science, therefore, laboratory works are essential and provide an enrichment for procedures and research that cannot be replaced by virtual laboratories. For all these reasons, this work focuses on the usefulness of the laboratory as a space with a problem-solving approach, which is, contextualizing problems and fulfilling a series of purposes. According to Zambrano (2007), these purposes are: ability to internalize general and specific knowledge (to know), to acquire technical and procedural skills (to know how), to develop attitudes (to know how to be) and social skills (to know how to live together). The intention of this article is to show that, including chemistry laboratories self-managed by the students themselves, generates one of the fundamental competences in our changing society, such as self-learning (learning to learn).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Cellular strategies for retinal repair by photoreceptor replacement

Loss of photoreceptors due to retinal degeneration is a major cause of blindness in the developed world. While no effective treatment is currently available, cell replacement therapy, using pluripotent stem cell-derived photoreceptor precursor cells, may be a feasible future treatment. Recent reports have demonstrated rescue of visual function following the transplantation of immature photoreceptors and we have seen major advances in our ability to generate transplantation-competent donor cells from stem cell sources. Moreover, we are beginning to realise the possibilities of using endogenous populations of cells from within the retina itself to mediate retinal repair. Here, we present a review of our current understanding of endogenous repair mechanisms together with recent progress in the use of both ocular and pluripotent stem cells for the treatment of photoreceptor loss. We consider how our understanding of retinal development has underpinned many of the recent major advances in translation and moved us closer to the goal of restoring vision by cellular means

Differences of corruption types in selected Western and central-eastern health systems during the COVID-19 pandemic: a rapid review

YesTo identify, describe, and classify the cases of health corruption present in selected Western [the Netherlands and the United Kingdom (UK)] and Central-Eastern European (Poland and Slovakia) countries during the COVID-19 pandemic. A rapid review of the literature was conducted, evaluating data from 11 March 2020 to 15 April 2021. Information sources included MEDLINE via WoS, IBSS via ProQuest, Scopus, and gray literature. Thirteen cases were identified across the four countries. The primary type of health corruption in Western European countries was procurement corruption, while misuse of (high) level positions was the most prevalent in Central-Eastern European countries. Actors from central governments were most involved in cases. The rule of law and anti-corruption watchdogs reported most cases in the United Kingdom and the Netherlands, while the media reported cases in Poland and Slovakia. The differences in types of corruption in WE and CEE countries emphasize the need to contextualize the approach to tackle corruption. Thus, further research in preventing and tackling corruption is a vital and necessary undertaking despite the inherent of conducting health corruption research