Principales cambios en la epidemiología de las enfermedades infecciosas en el mundo

ResumenEste trabajo revisa el concepto y el impacto de las nuevas enfermedades infecciosas y las razones para su emergencia; a partir de ahí, describe algunas estrategias para su control. Entre estas medidas se encuentra, en primer lugar. el fortalecimiento de los servicios de salud pública, como la vigilancia epidemiológica y los laboratorios de salud pública, que permitan identificar nuevos brotes y nuevas enfermedades infecciosas. En segundo lugar la difusión rápida de los conocimientos generados, hasta las personas encargadas del control de enfermedades. En tercer lugar, la promoción de la investigación en este campo y la formación de personal especializado. Dentro de la investigación es prioritario el desarrollo de nuevas vacunas, potencialmente útiles también para el control de las enfermedades crónicas, consideradas hasta ahora como no infecciosas (úlceras péptica, coronariopatías, etcétera). Por último, se recomienda un “nuevo abordaje epidemiológico”, que integre los aspectos médicos y sociales de las enfermedades. Este abordaje es además el que permite la necesaria colaboración con los profesionales de otros campos, como la inmunología, la microbiología, la clínica y las ciencias sociales.SummaryThis paper reviews the concept and impact of new infectious diseases and the reasons for their emergence; taking that as a start, it describes some strategies to control them. Among these measures we can find, firstly, the strengthening of public health services, such as epidemiological surveillance and public health laboratories, which allow us to identify new outbreaks and new infectious diseases. Secondly, the quick spread of the knowledge that is generated towards the people who are in charge of the control of diseases, and thirdly, the promotion of research in this field and the training of specialized staff. In the field of research, priority is given to the development of new vaccinations that are potentially useful for the control of chronic diseases which were considered until now as non-infectious (peptic ulcer, coronarypathies, etc.). Finally, a new epidemiological approach which integrates medical and social aspects of diseases is advised. Besides, this approach is what allows the necessary collaboration with professionals from other fields, such as immunology, microbiology, clinics and social sciences

The influence of holes in the mechanical properties of EWT solar cells

EWT back contact solar cells are manufactured from very thin silicon wafers. These wafers are drilled by means of a laser process creating a matrix of tiny holes with a density of approximately 125 holes per square centimeter. Their influence in the stiffness and mechanical strength has been studied. To this end, both wafers with and without holes have been tested with the ring on ring test. Numerical simulations of the tests have been carried out through the Finite Element Method taking into account the non-linearities present in the tests. It's shown that one may use coarse meshes without holes to simulate the test and after that sub models are used for the estimation of the stress concentration around the holes

Structure of recent sedimentary units in the Galician continental shelf

[Resumen] Los 'perfiles·· de sísmica de reflexión de alta resolución en la plataforma continental gallega nos permiten conocer la estratigrafía de los sedimentos holocenos. De techo a muro se distinguen: - Un nivel superior de limos holocenos marinos con interestratificaciones de arena. - Un reflector basal que aflora hacia~·ra zona Inedia y externa de la plataforma continental y formado por varias superficies erosionales debidas a lo reducido de los aportes sedimentarios en ese punto. - Un basamento acústico de naturaleza ígnea y metamórfica con una fuerte respuesta sísmica. La plataforma se caracteriza por el desarrollo de dos cuerpos de arena limosa que se extiende hacia mar abierto desde la zona interior de plataforma hacia el sur y una superficie de progradaci6n en la zona externa de la plataforma. El mapa de isopacas demuestra que los sedimentos marinos holocenos forman ... generalmente un lecho contínuo que alcanza su máximo espesor delante de las rías.[Abstract] High-resolution seismic reflection profiles of Galician Continental Shelf show the shallow seismic stratigraphy of Holocene sediments. Three acoustic units can be distinguished from top bottom: - a continuous upper layer of Holocene marine muds with interstratifications of sand. - a basal reflector which outcrops towards the middle and outer continental shelf, forming several erosional surfaces due to reduced sediment supply. - an acoustic basement, of igneous and metarnorphic nature; with strong seismic response. The shelf is characterized by the development of two bodies of sandy mud that extends offshore from the inner shelf toward the south and a progradation surface on the outer shelf. The isopac map shows that the Holocene marine sediments generally form a continuous layer that reachs a maximum thickness in front of the «rias»

The Fermi Problem in Discrete Systems

The Fermi two-atom problem illustrates an apparent causality violation in Quantum Field Theory which has to do with the nature of the built in correlations in the vacuum. It has been a constant subject of theoretical debate and discussions during the last few decades. Nevertheless, although the issues at hand could in principle be tested experimentally, the smallness of such apparent violations of causality in Quantum Electrodynamics prevented the observation of the predicted effect. In the present paper we show that the problem can be simulated within the framework of discrete systems that can be manifested, for instance, by trapped atoms in optical lattices or trapped ions. Unlike the original continuum case, the causal structure is no longer sharp. Nevertheless, as we show, it is possible to distinguish between "trivial" effects due to "direct" causality violations, and the effects associated with Fermi's problem, even in such discrete settings. The ability to control externally the strength of the atom-field interactions, enables us also to study both the original Fermi problem with "bare atoms", as well as correction in the scenario that involves "dressed" atoms. Finally, we show that in principle, the Fermi effect can be detected using trapped ions.Comment: Second version - minor change

The Immigration Selection System: A Proposal for Reform

This Article reviews the historical background of our present immigration law and analyzes the policy goals of immigration law in light of the major contemporary issues that bear directly on the immigration act: population growth, the requirements of the labor force, family reunion, illegal immigration, and refugee admission. The authors contend that the immigration act in its present form does not adequately deal with the expanding nature of these problems, and offer recommendations to reconcile present deficiencies with recent and foreseeable world developments. The authors suggest reforms that would balance humanitarian goals with domestic, political, socioeconomic, demographic, and foreign policy impacts

Regulation of Ace2-dependent genes requires components of the PBF complex in schizosaccharomyces pombe

The division cycle of unicellular yeasts is completed with the activation of a cell separation program that results in the dissolution of the septum assembled during cytokinesis between the 2 daughter cells, allowing them to become independent entities. Expression of the eng1+ and agn1+ genes, encoding the hydrolytic enzymes responsible for septum degradation, is activated at the end of each cell cycle by the transcription factor Ace2. Periodic ace2+ expression is regulated by the transcriptional complex PBF (PCB Binding Factor), composed of the forkhead-like proteins Sep1 and Fkh2 and the MADS box-like protein Mbx1. In this report, we show that Ace2-dependent genes contain several combinations of motifs for Ace2 and PBF binding in their promoters. Thus, Ace2, Fkh2 and Sep1 were found to bind in vivo to the eng1+ promoter. Ace2 binding was coincident with maximum level of eng1+ expression, whereas Fkh2 binding was maximal when mRNA levels were low, supporting the notion that they play opposing roles. In addition, we found that the expression of eng1+ and agn1+ was differentially affected by mutations in PBF components. Interestingly, agn1+ was a major target of Mbx1, since its ectopic expression resulted in the suppression of Mbx1 deletion phenotypes. Our results reveal a complex regulation system through which the transcription factors Ace2, Fkh2, Sep1 and Mbx1 in combination control the expression of the genes involved in separation at the end of the cell division cycle

Rotura de cotilo en artroplastia total de cadera

Describimos dos casos de rotura de cotilos de expansión de prótesis de cadera tipo CLS de origen no traumático. Ambos casos sucedieron a los seis años de cirugía y no se apreció desgaste o rotura del polietileno en ninguno de ellos. En nuestra opinión la hipótesis más probable es que la falta de contacto entre la zona polar del cotilo y el fondo del acetábulo produzca una zona de inestabilidad en los segmentos de la prótesis y rotura por fatiga del material. Creemos que es obligado su recambio aunque el paciente no presente sintomatología actual, ya que la rotura del acetábulo conducirá a un aflojamiento y a una osteolisis secundaria.We describe two cases of breakage of expansion cups in a CLS uncemented total hip arthroplasty wihtout traumatic etiologic. Both cases occurred six years after the surgery and none had breakage or polyethylene wear. We postulate that the lack of contact between the polar area of the cup and the acetabulum produces a zone of instability in the segments of the prosthesis and increases the risk of fatigue of the material. In our opinion acetabular revision is mandatory in this situation, even in asymptomatic cases, because cup rupture leads to implant loosening with secondary short-team osteolysis