Oceanic laser-induced breakdown spectroscopy. Development and application for the analysis of submerged solids

Hoy en día, la caracterización del patrimonio cultural subacuático se ha convertido en una de las áreas más interesantes de la arqueología. El mar Mediterráneo es rico en restos arqueológicos debido a tormentas, accidentes y batallas navales desde tiempos prehistóricos y sólo en el sur de España ya se localizan varios cientos de yacimientos submarinos. Los valores históricos y culturales y el impacto económico de estos hallazgos hacen necesaria la existencia de mecanismos de control para ayudar a la preservación del patrimonio cultural. Así como, la información química extraída de las materias primas utilizadas en la antigüedad y la tecnología empleada en la producción de objetos arqueológicos resulta fundamental para una mejor comprensión de los acontecimientos históricos. Sin embargo, a veces extraer este material de su entorno no es posible debido al tamaño de la muestra, o no está permitido por la legislación o las prácticas de conservación. De hecho, el análisis in situ se convierte en la única alternativa para obtener la información de composición química del objeto. En este contexto, la Espectroscopía de Plasmas Inducidos por Láser (LIBS) proporciona una solución para este problema, ya que combina muchas de las características necesarias para esta aplicación, incluyendo información multi-elemental, no necesita preparación de muestras, capacidad ilimitada de material y análisis en tiempo real. De hecho podría ser posible utilizar varias configuraciones de trabajo tales como: i) un instrumento LIBS remoto basado en la transmisión de radiación láser utilizando un cable de fibra óptica. ii) un instrumento LIBS operado a distancia que implique la entrega de un pulso láser enfocado hacia la muestra a través del medio acuoso y luego la transmisión de la luz emitida por el plasma inducido por láser de nuevo vuelva al sistema de detección. Ambas alternativas son muy desafiantes y motivan la realización de esta Tesis que se divide en dos partes principales. Parte I se centra en la configuración de un sistema LIBS remoto capaz de realizar análisis LIBS en yacimientos arqueológicos hasta 50 metros de profundidad. En este sentido se evalúa la estabilidad y robustez, así como la adaptación al medio marino, del instrumento LIBS remoto. Se optimizan las condiciones operativas necesarias para obtener, en condiciones extremas, datos analíticos útiles para identificar y preservar el patrimonio cultural sumergido. Así como se diseña, construye y evalúa un método discriminatorio que permita la clasificación in situ de los objetos más comunes que se encuentren en un naufragio. Parte II se evalúa en laboratorio la viabilidad de diseñar un instrumento operado a distancia utilizando la técnica LIBS para el análisis de objetos situados en un entorno de profundidad oceánica. En esta sección se presta especial atención en el efecto de la presión hidrostática en aspectos fundamentales para la formación de plasma y los fenómenos posteriores a la formación de plasma en muestras sólidas sumergidas, así como en la señal de emisión de la misma. Con el objetivo de aumentar la calidad espectral se ha evaluado una configuración de excitación de doble pulso, así como, se han optimizado los parámetros operacionales tales como longitud de onda, la energía por impulso y la geometría de recolección entre otros. En resumen, los resultados obtenidos en el presente trabajo de investigación suponen un paso hacia adelante en el uso de la técnica LIBS como herramienta para el análisis de muestras arqueológicas sumergidas situadas a media y alta profundidad

Global Governance and the Emergence of Global Institutions for the 21st Century

All those who despair at the state of the world and its multiple problems will find in this book ambitious but reasonable proposals that will give our globalized world the institutions of international governance necessary to resolve pressing problems including peace, security, and climate change. This title is also available as Open Access

Cáncer gástrico y sus factores de pronósticos de supervivencia en pacientes tratados en el hospital Daniel Alcides Carrión EsSalud de Tacna, periodo enero 2015 - diciembre 2019

Introducción. El cáncer gástrico es el quinto cáncer diagnosticado con mayor frecuencia y la tercera causa principal de muerte por cáncer en el mundo, a pesar de que ha experimentado una disminución la última mitad de siglo en la mayoría de los países. Objetivo: Determinar los factores pronósticos de la supervivencia por cáncer gástrico en el Hospital Daniel Alcides Carrión EsSalud de Tacna en el periodo enero 2015 a diciembre 2019. Métodos: Se realizó un estudio observacional, ambispectivo y analítico, en el que participaron 62 pacientes atendidos en el Hospital EsSalud DAC Tacna durante el periodo enero 2015– diciembre 2019. Se utilizó una ficha de recolección para obtener datos sociodemográficos y clínicos. Resultados: edad promedio de 64,67 ± DE 14,49; predominio de adenocarcinoma diferenciado (71%); compromiso del ápice de la glándula (71%), localización preferente en el cuerpo y antro (62,9%) y tratamiento quirúrgico (62,9%); promedio de supervivencia de 31,32 meses y la proporción de vivos es de 42 % a los 60 meses de seguimiento. Los factores pronósticos para tiempos de sobrevida incluyeron la histología del tumor adenocarcinoma diferenciado; localización de la tumoración en el cuerpo; compromiso glandular submucoso; tratamiento de quimioterapia o quirúrgico. Conclusiones: En el presente estudio se encontró que la histología (p:0,001), la localización del tumor(p:0,001), el tipo de tratamiento (p:0,001), el compromiso glandular (p:0,001), son factores pronósticos significativos de la supervivencia en pacientes con cáncer gástrico en el Hospital Daniel Alcides Carrión EsSalud de Tacna en el periodo enero 2015- diciembre 2019

Determining the annual periodicity of growth rings in seven tree species of a tropical moist forest in Santa Cruz, Bolivia

To determine the annual periodicity of growth rings in seven tree species from a tropical moist forest in Santa Cruz, Bolivia, a fire scar was used as a marker point to verify the annual nature of tree rings. The number of tree rings formed between the 1995 fire scar and the collection of the cross sections in 2002 was visually identified. The seven species showed annual growth rings. In most cases, boundaries between rings were marked by the presence of marginal parenchyma and wall-thicked fibers formed at the end of the growing season. Growth lenses and false rings were recorded in some species. Tree rings can be carefully used in Santa Cruz forests to determine rates of growth. This information is crucial for defining forest management practices in tropical regions

Diameter growth rates in tropical dry forests: contributions to the sustainable management of forests in the Bolivian Cerrado biogeographical province

Growth ring variations were used to provide the rates in diameter growth for seven tree species in the Bolivian Cerrado biogeographical province. Ten to 50 trees were measured per species. Ring width measurements provided accurate data on the rates of tree growth. Variations in growth rates were determined among species and among sites for the same species over a common period of 100 years. Diametric increases range from 0.43 to 0.56 cm year-1 in Chiquitano biogeographical district. For species in Guarayos district, diametric increments range from 0.51 to 1.06 cm year-1. For Centrolobium microchaete growing in both districts, the annual diametric increments oscillate between 0.35 to 0.40 cm year-1 and 0.55 to 0.65 cm year-1 in Chiquitano and Guarayos districts, respectively. Diametric increases in Chiquitano district were not significantly different among sites, whereas in Guarayos district, annual increases differ among species and from the same species growing in Chiquitano district. Observed diameter growth rates indicate that diametrical increments are generally slower than commonly assumed, with considerable variation among species and between districts. Therefore, the idea of applying similar rules for the management of different species across different sites without considering actual growth rates is not recommended, with long-term consequences for the sustainability of forests at the tropical dry Bolivian Cerrado

In vitro secretion profiles of interleukin (IL)-1beta, IL-6, IL-8, IL-10, and TNF alpha after selective infection with Escherichia coli in human fetal membranes

<p>Abstract</p> <p>Background</p> <p>Chorioamniotic membranes infection is a pathologic condition in which an abnormal secretion of proinflammatory cytokines halts fetal immune tolerance. The aim of the present study was to evaluate the functional response of human chorioamniotic membranes, as well as the individual contribution of the amnion and choriodecidua after stimulation with Escherichia coli, a pathogen associated with preterm labor.</p> <p>Methods</p> <p>Explants of chorioamniotic membranes from 10 women (37–40 weeks of gestation) were mounted and cultured in a Transwell system, which allowed us to test the amnion and choriodecidua compartments independently. Escherichia coli (1 × 10 6 CFU/mL) was added to either the amniotic or the choriodecidual regions or both; after a 24-h incubation, the secretion of IL-1beta, IL-6, TNFalpha, IL-8, and IL-10 in both compartments was measured using a specific ELISA. Data were analyzed by Kruskal-Wallis one-way analysis of variance.</p> <p>Results</p> <p>After stimulation with Escherichia coli, the choriodecidua compartment showed an increase in the secretion of IL-1beta (21-fold), IL-6 (2-fold), IL-8 (6-fold), and IL-10 (37-fold), regardless of which side of the membrane was stimulated; TNFalpha secretion augmented (22-fold) also but only when the stimulus was applied simultaneously to both sides. When the amnion was stimulated directly, the level of IL-1beta (13-fold) rose significantly; however, the increase in IL-8 secretion was larger (20-fold), regardless of the primary site of infection. TNFalpha secretion in the amnion compartment rose markedly only when Escherichia coli was simultaneously applied to both sides.</p> <p>Conclusion</p> <p>Selective stimulation of fetal membranes with Escherichia coli results in a differential production of IL-1beta, IL-6, TNFalpha, IL-8, and IL-10. These tissues were less responsive when the amnion side was stimulated. This is in agreement with the hypothesis that the choriodecidua may play a primary role during an ascending intrauterine infection, being the main barrier to progression of the infection into the amniotic cavity. Therefore, the tissue-specific capacities for the secretion of these immune modulators could be a determining factor for the degree of severity of the inflammation process in fetal membranes.</p

Levels and Correlates of Non-Adherence to WHO Recommended Inter-Birth Intervals in Rufiji, Tanzania.

Poorly spaced pregnancies have been documented worldwide to result in adverse maternal and child health outcomes. The World Health Organization (WHO) recommends a minimum inter-birth interval of 33 months between two consecutive live births in order to reduce the risk of adverse maternal and child health outcomes. However, birth spacing practices in many developing countries, including Tanzania, remain scantly addressed. METHODS: Longitudinal data collected in the Rufiji Health and Demographic Surveillance System (HDSS) from January 1999 to December 2010 were analyzed to investigate birth spacing practices among women of childbearing age. The outcome variable, non-adherence to the minimum inter-birth interval, constituted all inter-birth intervals <33 months long. Inter-birth intervals >=33 months long were considered to be adherent to the recommendation. Chi-Square was used as a test of association between non-adherence and each of the explanatory variables. Factors affecting non-adherence were identified using a multilevel logistic model. Data analysis was conducted using STATA (11) statistical software. RESULTS: A total of 15,373 inter-birth intervals were recorded from 8,980 women aged 15--49 years in Rufiji district over the follow-up period of 11 years. The median inter-birth interval was 33.4 months. Of the 15,373 inter-birth intervals, 48.4% were below the WHO recommended minimum length of 33 months between two live births. Non-adherence was associated with younger maternal age, low maternal education, multiple births of the preceding pregnancy, non-health facility delivery of the preceding birth, being an in-migrant resident, multi-parity and being married. CONCLUSION: Generally, one in every two inter-birth intervals among 15--49 year-old women in Rufiji district is poorly spaced, with significant variations by socio-demographic and behavioral characteristics of mothers and newborns. Maternal, newborn and child health services should be improved with a special emphasis on community- and health facility-based optimum birth spacing education in order to enhance health outcomes of mothers and their babies, especially in rural settings

Hypervariability within the Rifin, Stevor and Pfmc-2TM superfamilies in Plasmodium falciparum

The human malaria parasite, Plasmodium falciparum, possesses a broad repertoire of proteins that are proposed to be trafficked to the erythrocyte cytoplasm or surface, based upon the presence within these proteins of a Pexel/VTS erythrocyte-trafficking motif. This catalog includes large families of predicted 2 transmembrane (2TM) proteins, including the Rifin, Stevor and Pfmc-2TM superfamilies, of which each possesses a region of extensive sequence diversity across paralogs and between isolates that is confined to a proposed surface-exposed loop on the infected erythrocyte. Here we express epitope-tagged versions of the 2TM proteins in transgenic NF54 parasites and present evidence that the Stevor and Pfmc-2TM families are exported to the erythrocyte membrane, thus supporting the hypothesis that host immune pressure drives antigenic diversity within the loop. An examination of multiple P.falciparum isolates demonstrates that the hypervariable loop within Stevor and Pfmc-2TM proteins possesses sequence diversity across isolate boundaries. The Pfmc-2TM genes are encoded within large amplified loci that share profound nucleotide identity, which in turn highlight the divergences observed within the hypervariable loop. The majority of Pexel/VTS proteins are organized together within sub-telomeric genome neighborhoods, and a mechanism must therefore exist to differentially generate sequence diversity within select genes, as well as within highly defined regions within these genes

Inequality, Fiscal Capacity and the Political Regime: Lessons from the Post-Communist Transition

Using panel data for twenty-seven post-communist economies between 1987-2003, we examine the nexus of relationships between inequality, fiscal capacity (defined as the ability to raise taxes efficiently) and the political regime. Investigating the impact of political reform we find that full political freedom is associated with lower levels of income inequality. Under more oligarchic (authoritarian) regimes, the level of inequality is conditioned by the state’s fiscal capacity. Specifically, oligarchic regimes with more developed fiscal systems are able to defend the prevailing vested interests at a lower cost in terms of social injustice. This empirical finding is consistent with the model developed by Acemoglu (2006). We also find that transition countries undertaking early macroeconomic stabilisation now enjoy lower levels of inequality; we confirm that education fosters equality and the suggestion of Commander et al (1999) that larger countries are prone to higher levels of inequality.http://deepblue.lib.umich.edu/bitstream/2027.42/57211/1/wp831 .pd