Traceability for Model Driven, Software Product Line Engineering

Traceability is an important challenge for software organizations. This is true for traditional software development and even more so in new approaches that introduce more variety of artefacts such as Model Driven development or Software Product Lines. In this paper we look at some aspect of the interaction of Traceability, Model Driven development and Software Product Line

FLAT PLATE PULSATING HEAT PIPES WITH DIFFERENT CHANNEL GEOMETRIES FOR HIGH HEAT FLUX APPLICATIONS

The thermal performance of flat plate pulsating heat pipes with differentchannel geometries was performed in this experimental work. The testswere accomplished with two channel profiles, round and grooved. One ofthe channel geometries, located on the evaporator, can be considered novel,consisting of a round channel with two lateral grooves. Diffusion bondingtechnology was used to manufacture the PHPs made of two copper flatplates. Distilled water was used as the working fluid with a filling ratio of50% (17.9 ml) of the total volume. The pulsating heat pipes were tested atone position (vertical) under heat loads from 20 up to 2000 W. Theexperimental results showed that both flat plate pulsating heat pipesoperates successfully for high heat fluxes. The lateral grooves reduced thethermal resistance, being principally efficient in lower loads. Besides that,the novel channel considerably anticipated the operation startup. Therefore,a much better performance was obtained by the grooved channel PHP,which was constructed from a simple, low cost modification of thefabrication process

Zebrafish macroH2A variants have distinct embryo localization and function

Mouse and cell-based studies have shown that macroH2A histone variants predominantly associate with heterochromatin. Functional studies found that macroH2As are involved in gene repression, inhibiting the acquisition of pluripotency and preserving cell differentiation. However, only a few studies have analysed the role of macroH2A during early embryo development. We report the development of transgenic zebrafish lines expressing macroH2A isoforms (mH2A1 and mH2A2) fusion proteins (with GFP) under identified endogenous promoters. We found that mH2A1 and mH2A2 have different spatial and temporal expression patterns during embryonic development. mH2A1 is expressed mostly in the extraembryonic Yolk Syncytial Layer (YSL) starting before shield stage and decreasing once morphogenesis is completed. mH2A2 expression lags behind mH2A1, becoming evident at 24 hpf, within the whole body of the embryo proper. Our ChIP-seq analysis showed that mH2A1 and mH2A2 bind to different DNA regions, changing dramatically after gastrulation. We further analysed RNA-seq data and showed that there is not a general/unspecific repressing function of mH2A1 or mH2A2 associated with heterochromatin but a fine regulation depending on cell types and stage of development. mH2A1 downregulates DNA expression in specific cells and embryo stages and its effect is independent of heterochromatin formation but it is correlated with nucleus quiescence instead. Whereas mH2A2 DNA association correlates with upregulation of differentially expressed genes between 75% epiboly and 24 hpf stages. Our data provide information for underlying molecules that participate in crucial early developmental events, and open new venues to explore mH2A related mechanisms that involve cell proliferation, differentiation, migration and metabolism

El Programa de Investigación en Maíz: objetivos, resultados y proyecciones.

En el presente documento los autores reseñan lo que ha sido el Programa de Maíz en el ICA teniendo en cuenta los objetivos planteados, los resultados y las proyecciones propuestas. Para ello inicialmente, se muestra la importancia del maíz como alimento, el área cultivada, la producción y productividad a nivel nacional basandose en tablas que muestran series históricas desde 1950 hasta 1983 del área en producción y rendimiento en Colombia. Con el objeto de elevar los niveles de productividad de maíz, el ICA elaboró el Plan Nacional de Investigación en el Cultivo de Maíz, el cual hace parte del Plan Nacional de Investigación Agropecuaria del ICA(PLANIA) para 1981 a 1986 los objetivos del primer plan eran: obtener información básica y detectar los factores limitantes en la producción del maíz, determinar el grado de tecnología disponible, establecer prioriddades de investigación y formular los proyectos de investigación para los 5 años siguientes. Se realizaron investigacioes en fitomejoramiento, suelos, fisiología, fitopatología, entomología, recursos de agua y tierra, maquinaria agrícola, procesos agrícolas y todos los factaores socioeconómicos involucrados en el proceso de producción. Los resultados de este plan para 1983 muestran la producción de 73 diferentes tipos mejorados de maíz y el programa ha autorizado la comercialización de 9 genotipos de maíz. Se enumeran las empresas que también se dedican a la multiplicación, distribución y venta de semillas de maíz en Colombia Finalmente se enumeran los proyectos contemplados por el PLANIA en maíz, los cuales son los señalados anteriormente de los que se espera una respuesta efectia a los factores tecnológicos limitantes de la producción del cultivo de maízMaíz-Zea may

Resistance to autosomal dominant Alzheimer's disease in an APOE3 Christchurch homozygote: a case report.

We identified a PSEN1 (presenilin 1) mutation carrier from the world's largest autosomal dominant Alzheimer's disease kindred, who did not develop mild cognitive impairment until her seventies, three decades after the expected age of clinical onset. The individual had two copies of the APOE3 Christchurch (R136S) mutation, unusually high brain amyloid levels and limited tau and neurodegenerative measurements. Our findings have implications for the role of APOE in the pathogenesis, treatment and prevention of Alzheimer's disease

Human chromosome 11 contains two different growth suppressor genes for embryonal rhabdomyosarcoma.

The identification of acquired homozygosity in human cancers implies locations of tumor suppressor genes without providing functional evidence. The localization of a defect in embryonal rhabdomyosarcomas to chromosomal region 11p15 provides one such example. In this report, we show that transfer of a normal human chromosome 11 into an embryonal rhabdomyosarcoma cell line elicited a dramatic loss of the proliferative capacity of the transferrants. Indeed, the majority of the viable microcell hybrids had either eliminated genetic information on the short arm of the transferred chromosome 11 or increased the copy number of the rhabdomyosarcoma-derived chromosomes 11. Cells that possessed only the long arm of chromosome 11 also demonstrated a decreased growth rate. In contrast, all microcell hybrids retained the ability to form tumors upon inoculation into animals. These functional data support molecular studies indicating loss of genetic information on chromosome 11p15 during the development of embryonal rhabdomyosarcoma. In addition, our studies demonstrate the existence of a second gene on the long arm, previously unrecognized by molecular analyses, which negatively regulates the growth of embryonal rhabdomyosarcoma cell lines

Arbuscular mycorrhizal fungi associated to Zea Mays L. plants in an agroecosystem of Atlántico, Colombia.

El maíz es considerado uno de los más importantes cultivos a nivel mundial. Como en muchos otros países, Colombia ha utilizado este cereal no solo como alimento para humanos y animales sino también para fabricar diferentes productos industriales. Las plantas de maíz están bien adaptadas a las diferentes condiciones climáticas y agroecológicas de Colombia, lo cual le permite estar ampliamente distribuido en todo el país. Algunas de sus adaptaciones naturales son atribuidas a la existencia de relaciones simbióticas con hongos micorrizógenos arbusculares (HMA), los cuales promueven la captación de nutrientes en especial de aquellos que tienen escasa movilidad tales como el fósforo (P) y el nitrógeno (N). Se identificaron HMA asociados a cultivos de maíz localizados en el municipio de Sabanalarga, Atlántico, Colombia. El número de esporas en 100 g de suelo se determinó mediante tamizado, siguiendo protocolos de centrifugación en sacarosa. El número de esporas por 100 g de suelo mostró diferencias estadísticas significativas durante los meses de muestreo (p<0,05). Se identificaron un total de 19 morfotipos correspondientes a doce especies del género Glomus, cinco del género Gigaspora y una especie para los géneros Acaulospora y Scutellospora. Se encontró correlación negativa entre temperatura y número de esporas; sin embargo no existió correlación entre el pH y las variables densidad de esporas, porcentaje de colonización y temperatura del suelo. Asimismo, se reportó bajo contenido de materia orgánica (0,99 %) y baja capacidad de intercambio catiónico (7,50 cmol.kgr-1suelo). Estos resultados, sumados al hecho de que este tipo de cultivos son grandemente dependientes de la actividad de hongos micorrizógenos, explican la densidad de esporas (400-1350 esp/100 g) y el elevado porcentaje de colonización (40-98 %) que fue encontrado durante el muestreo. Es claro que este cereal depende de la presencia de hongos micorrizógenos durante la toma de nutrientes.Corn is considered one of the most important cereal crops worldwide. As many other countries, Colombia has used this cereal not only to feed humans and animals but also to manufacture many different industrial products. Corn plants are well adapted in different climatic and ecological conditions in Colombia which allows it to be widely distributed throughout the country. Some of its natural adaptations are attributed to the existence of symbiotic relationships with Arbuscular Mycorrhizal fungi (AMF) which promote the nutrient uptake, especially those with known low mobility such as phosphorus (P) and nitrogen (N). AMFs associated to corn crops were identified in samples collected in the fields of the municipality of Sabanalarga (Atlántico, Colombia). The number of spores per 100 g of soil was determined by sieving following sucrose centrifugation standard protocols. The number of spores per 100 g of soil showed statistically significant differences during the months of sampling (p < 0.05). A total of 19 morphotypes, corresponding to twelve species of the genus Glomus, five of the genus Gigaspora, and one species of both genus Acaulospora and Scutellospora were identified. A negative correlation between temperature and number of spores was found but no correlation between pH and the spore density, percentage of colonization and soil temperature variables was found. Additionally, low organic matter content (0.99%) and low cation exchange capacity (7.50 cmol*soil-Kg-1) were reported. These results, in addition to the fact that this kind of crops are highly dependent of mycorrhizal fungi activity, explain the spore density (400-1350 spore/ 100 g) and the high percentage of colonization (40-98%) that were obtained during sampling. It is clear that this cereal crop depends on the presence of mycorrhizal fungi during nutrient uptake

Geologising urban political ecology (UPE): the urbanisation of sand in Accra, Ghana

This paper makes a call for an urban political ecology (UPE) which engages more extensively with Earth’s geological formations. As a material at the centre of global urbanisation process, sand is offered as a geological entry point. The paper presents an analysis of the urbanisation of sand, or the ways in which sand is brought into the urban realm, grounding this reading in Accra—a growing city on Ghana’s Atlantic coast. Drawing from 14 months of ethnographic fieldwork, the paper charts the socio-natural politics through which sand is first unearthed from the edges of the city—an extractive processes otherwise known as “sand winning” in Ghana. By examining the forms of power which govern uneven revenue flows to communities, the displacement of farming groups, the widespread loss of farmland and a contested regime of governance, the analysis exposes the socio-natural politics through which the city’s geological baseline is first unearthed