Crack origin and detection in thin cristallyne solar cells in a production line

In order to reduce cost and make up for the rising price of silicon, silicon wafers are sliced thinner and wider,eading to weaker wafers and increased breakage rates during fabrication process. In this work we have analysed different cracks origins and their effect on wafer’s mechanical strength. To enhance wafer’s strength some etching methods have been tested. Also, we have analysed wafers from different points of an entire standard production process. Mechanical strength of the wafers has been obtained via the four line bending test and detection of cracks has been tested with Resonance Ultrasonic Vibration (RUV) system, developed by the University of South Florida.

El dibujo como herramienta en el proceso creativo del cine y la arquitectura

El director de cine y el arquitecto, exploran las posibilidades que les ofrece la imagen, en el sentido de la visualización de ciertas relaciones que son catalizadoras de las emociones. La obra cinematográfica y la obra arquitectónica son producto del pensamiento y contienen todos los procesos que las idearon, así como aquellos mecanismos necesarios para generar el espacio y la secuencia. El objetivo general de la tesis consiste en conocer las analogías existentes en el modo en que el arquitecto y el cineasta afrontan el proceso de creación de sus proyectos desde la acción gráfica. Si consideramos el medio gráfico como un recurso creativo en el proyecto arquitectónico y cinematográfico, el boceto, croquis o “storyboard” se convierten en documentos fundamentales, objeto de estudio, para extraer las claves y la manera en que se desarrolla dicho proceso. El pensamiento gráfico se encuentra íntimamente unido a su modo de expresión. El estudio de ese proceso de pensamiento basado principalmente en imágenes, permite establecer analogías en la manera en que ambos autores hacen uso del dibujo para imaginar acontecimientos evocadores de emociones que definan el carácter dramático de sus ideas. La conexión y yuxtaposición de imágenes mentales, como operaciones de montaje que alientan la construcción de ideas, conceptos y sensaciones, son claves en el curso de la concepción arquitectónica y cinematográfica, y el dibujo, una herramienta que permite a ambos autores su desarrollo. La aproximación al modo en que el arquitecto y el cineasta emprenden el proceso de ideación de sus proyectos a través del dibujo, se aborda desde las estrategias gráficas de cuatro autores: Sergei Eisenstein, Le Corbusier, Akira Kurosawa y Rem Koolhaas. La estructura del trabajo se desarrolla en dos bloques. El primero, compuesto por los primeros cuatro capítulos, afronta desde un punto de vista general, la potencialidad de la imagen en el pensamiento gráfico y el papel de la acción gráfica en el curso proyectual que realiza el arquitecto, por un lado, y el director de cine por otro, tratando de extraer las analogías y los puntos de encuentro de ambos autores durante el proceso. El segundo bloque, correspondiente a los cuatro últimos capítulos, aborda el uso del medio gráfico de manera más concreta, en la figura de dos de los arquitectos y dos de los cineastas más influyentes del pasado y del presente siglo, tratando de comprender el papel del dibujo en el desarrollo conceptual de su obra. ABSTRACT Both the movie director and the architect explore the potential offered by the image, as the visualization of certain relations that are catalyst of emotions. Cinematography and architecture works are a result of a thought and they include all the processes that created them, as much as the essential tools to generate the space and the sequence. This thesis aims to get an understanding of the analogies underlying in which architects and movie directors face the creation process of theirs projects from the graphic action. If we consider graphic media as a creative resource in the architectural and the cinematographic project, the sketch or storyboard becomes the fundamental documents, the study object, to decode the clues and the way in which the process unfolds. Graphic thinking comes across its way of expression. The study of this thinking, based mainly in images, let set up analogies in a way in which both authors use a drawing to imagine events of emotions that define the dramatic nature of their ideas. The connection and juxtaposition of mental images, as editing or montages that encourage the creation of ideas, concepts and sensations, are key in the course of the architectural and the cinematographic conception, and the drawing, a tool that allows both authors their development. The approach to the way the architect and the movie director get to the process of the creation of their projects through the drawing is addressed from the graphic strategies of these four authors: Sergei Eisenstein, Le Corbusier, Akira Kurosawa and Rem Koolhaas. The structure of the work is developed in two blocks. The first one, the first four chapters, face up, from a general point of view, the potential of the image in the graphic thinking and the role of the graphic action in the course of the project, that architects, as well as movie directors, are making trying to find the analogies and common points during the process. The second block, the last four chapters, deal with the use of the graphic media in a more detail manner, taking as example two of the architects and two of the movie directors more influential of the past and the present centuries, trying to understand the role of the drawing in the conceptual development of the their work.

The C-terminal SET domains of ALL-1 and TRITHORAX interact with the INI1 and SNR1 proteins, components of the SWI/SNF complex

The ALL-1 gene was discovered by virtue of its involvement in human acute leukemia. Its Drosophila homolog trithorax (trx) is a member of the trx-Polycomb gene family, which maintains correct spatial expression of the Antennapedia and bithorax complexes during embryogenesis. The C-terminal SET domain of ALL-1 and TRITHORAX (TRX) is a 150-aa motif, highly conserved during evolution. We performed yeast two hybrid screening of Drosophila cDNA library and detected interaction between a TRX polypeptide spanning SET and the SNR1 protein. SNR1 is a product of snr1, which is classified as a trx group gene. We found parallel interaction in yeast between the SET domain of ALL-1 and the human homolog of SNR1, INI1 (hSNF5). These results were confirmed by in vitro binding studies and by demonstrating coimmunoprecipitation of the proteins from cultured cells and/or transgenic flies. Epitope-tagged SNR1 was detected at discrete sites on larval salivary gland polytene chromosomes, and these sites colocalized with around one-half of TRX binding sites. Because SNR1 and INI1 are constituents of the SWI/SNF complex, which acts to remodel chromatin and consequently to activate transcription, the interactions we observed suggest a mechanism by which the SWI/SNF complex is recruited to ALL-1/trx targets through physical interactions between the C-terminal domains of ALL-1 and TRX and INI1/SNR1.

Typing of urinary JC virus DNA offers a novel means of tracing human migrations

Although polyomavirus JC (JCV) is the proven pathogen of progressive multifocal leukoencephalopathy, the fatal demyelinating disease, this virus is ubiquitous as a usually harmless symbiote among human beings. JCV propagates in the adult kidney and excretes its progeny in urine, from which JCV DNA can readily be recovered. The main mode of transmission of JCV is from parents to children through long cohabitation. In this study, we collected a substantial number of urine samples from native inhabitants of 34 countries in Europe, Africa, and Asia. A 610-bp segment of JCV DNA was amplified from each urine sample, and its DNA sequence was determined. A worldwide phylogenetic tree subsequently constructed revealed the presence of nine subtypes including minor ones. Five subtypes (EU, Af2, B1, SC, and CY) occupied rather large territories that overlapped with each other at their boundaries. The entire Europe, northern Africa, and western Asia were the domain of EU, whereas the domain of Af2 included nearly all of Africa and southwestern Asia all the way to the northeastern edge of India. Partially overlapping domains in Asia were occupied by subtypes B1, SC, and CY. Of particular interest was the recovery of JCV subtypes in a pocket or pockets that were separated by great geographic distances from the main domains of those subtypes. Certain of these pockets can readily be explained by recent migrations of human populations carrying these subtypes. Overall, it appears that JCV genotyping promises to reveal previously unknown human migration routes: ancient as well as recent.

Abnormal development of secondary lymphoid tissues in lymphotoxin β-deficient mice

The tumor necrosis factor (TNF) family cytokines lymphotoxin (LT) α and LTβ form heterotrimers that are expressed on the surface of activated lymphocytes and natural killer cells; LTα homotrimers can be secreted as well. Mice with a disrupted LTα gene lack lymph nodes (LN), Peyer’s patches (PP), and follicular dendritic cell (FDC) networks and reveal profound defects of the splenic architecture. However, it is unclear which of these abnormalities is the result of the absence in LTα homotrimers or LTαβ heterotrimers. To distinguish between these two possibilities, a mouse strain deficient in LTβ was created employing Cre/loxP-mediated gene targeting. Mice deficient in LTβ reveal severe defects in organogenesis of the lymphoid system similar to those of LTα−/− mice, except that mesenteric and cervical LN are present in most LTβ-deficient mice. Both LTβ- and LTα-deficient mice show significant lymphocytosis in the circulation and peritoneal cavity and lymphocytic infiltrations in lungs and liver. After immunization, PNA-positive B cell clusters were detected in the splenic white pulp of LTβ-deficient mice, but FDC networks were severely underdeveloped. Collectively, these results indicate that LTα can signal independently from LTβ in the formation of PNA-positive foci in the spleen, and especially in the development of mesenteric and cervical LN.

Hypo-phosphorylation of the retinoblastoma protein (pRb) by cyclin D:Cdk4/6 complexes results in active pRb

In cycling cells, the retinoblastoma protein (pRb) is un- and/or hypo-phosphorylated in early G1 and becomes hyper-phosphorylated in late G1. The role of hypo-phosphorylation and identity of the relevant kinase(s) remains unknown. We show here that hypo-phosphorylated pRb associates with E2F in vivo and is therefore active. Increasing the intracellular concentration of the Cdk4/6 specific inhibitor p15INK4b by transforming growth factor β treatment of keratinocytes results in G1 arrest and loss of hypo-phosphorylated pRb with an increase in unphosphorylated pRb. Conversely, p15INK4b-independent transforming growth factor β-mediated G1 arrest of hepatocellular carcinoma cells results in loss of Cdk2 kinase activity with continued Cdk6 kinase activity and pRb remains only hypo-phosphorylated. Introduction of the Cdk4/6 inhibitor p16INK4a protein into cells by fusion to a protein transduction domain also prevents pRb hypo-phosphorylation with an increase in unphosphorylated pRb. We conclude that cyclin D:Cdk4/6 complexes hypo-phosphorylate pRb in early G1 allowing continued E2F binding.

The interaction between cytoplasmic dynein and dynactin is required for fast axonal transport

Fast axonal transport is characterized by the bidirectional, microtubule-based movement of membranous organelles. Cytoplasmic dynein is necessary but not sufficient for retrograde transport directed from the synapse to the cell body. Dynactin is a heteromultimeric protein complex, enriched in neurons, that binds to both microtubules and cytoplasmic dynein. To determine whether dynactin is required for retrograde axonal transport, we examined the effects of anti-dynactin antibodies on organelle transport in extruded axoplasm. Treatment of axoplasm with antibodies to the p150Glued subunit of dynactin resulted in a significant decrease in the velocity of microtubule-based organelle transport, with many organelles bound along microtubules. We examined the molecular mechanism of the observed inhibition of motility, and we demonstrated that antibodies to p150Glued disrupted the binding of cytoplasmic dynein to dynactin and also inhibited the association of cytoplasmic dynein with organelles. In contrast, the anti-p150Glued antibodies had no effect on the binding of dynactin to microtubules nor on cytoplasmic dynein-driven microtubule gliding. These results indicate that the interaction between cytoplasmic dynein and the dynactin complex is required for the axonal transport of membrane-bound vesicles and support the hypothesis that dynactin may function as a link between the organelle, the microtubule, and cytoplasmic dynein during vesicle transport.