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We described the synthesis of multilayer organic thin films prepared by sequential vapor-phase coupling of monomers. The reactions were carried out at room temperature and atmospheric pressure. Films prepared using up to six sequential coupling reactions are reported. Homobifunctionalized monomers, such as hexamethylenediamine, react primarily via a single endgroup rather than cross coupling to the reactive surface via both reactive groups. We synthesized bifunctionalized polyamidoamine (PAMAM) dendrimers having both quaternary ammonium groups and primary amines on their periphery were prepared. The high positive charge on the surface of these dendrimers prevents agglomeration, and the unquanternized amine groups provide a reactive handle for immobilizing the dendrimer-encapsulated nanoparticles onto surfaces. We prepared highly monodisperse, 1-2 nm diameter Au nanoparticles using bifunctionalized PAMAM dendrimers as templates. The synthesis is carried out in water, takes less than 30 min, and requires no subsequent purification. The high monodispersity is a function of the template synthesis, which avoids size variations arising from random nucleation and growth phenomena, and the use of magic number equivalent ratios of AuCl4-/dendrimer. We investigated the electrochemical properties of Au, Pd and PdAu monolayer-protected clusters (MPCs), prepared by dendrimer-templating and subsequent extraction, are described. Purification of the extracted Au, Pd and PdAu nanoparticles was not required to obtain well-defined differential pulse voltammetry peaks arising from quantized double-layer charging. The calculated sizes of the nanoparticles were essentially identical to those determined from the electrochemical data. The capacitance of the particles was independent of the composition of core metal.

Nowadays, China is one of the most focused countries in the world since it has a very high potential to overwhelm the world market. As a result, we can find lots of articles and discussion about the activities of internationalization and relocation of many inter-national firms (both MNEs and SMEs) in China. Those firms moved to China in order to either serve the huge Chinese domestic market or enjoy the cheap production costs to supply the global market. However, there is one phenomenon that is not new and seldom has researches discussing about it. This is the fact that there are also a lot of Chinese entrepreneurs who moved out of China and located in other countries. In this re-search, we study about some Chinese firms which set up their sales agencies in the sales offices and distribution clusters in four European countries which are Poland, Spain, Portugal and Italy. We focus our study on the internationalization process of those Chi-nese firms, the rationales and factors influencing the location-decision and clustering and the rationales of choosing the specific countries in Europe. However, we have our latent objective, which is to stimulate more discussion and research on this interesting phenomenon since there are few researches on it. In our research, we find that there are similar patterns of internationalization process and location-decision of Chinese firms nevertheless the differences in background and types of business they have. They have some common rationales to undertake interna-tionalization, like to avoid fierce competition in the previous market, or to find new business opportunities and so on. Most of Chinese firms are still in the initial step of in-ternationalization process, and a very common way to fulfil their internationalization is by either the Chinese owners immigrating or registering a new firm in the host countries. The help from their friends and relatives who are often earlier arrivals in the host coun-tries and the strong connection with the suppliers in China are their competitive advan-tages. However, they have encountered some common problems, such as cultural issues, like language barriers and communication problems; lack of knowledge about local market and political issues. For localization or the way they choose their locations, we find some common locational factors, like market size, degree of competition, government policy (mainly on immigration policy), connectivity, safety, transaction costs and ethnic contacts. For the last section of our study, cluster, we find that the formation of cluster are based mainly on potential benefits of cluster, such as ability to attract more customers(market size), benefits from collaboration and information sharing, availabil-ity of specialized services and supporting firms. At last, we find a lot of interesting top-ics for future research.

A total of 840 fish species names (belonging to 143 families) were gathered from the Taiwan coastal area-economic geographical database. [http://fishdb.sinica.edu. tw/ 2001new/main1.asp] The near-shore area of Taiwan were divided into eight areas for studies of geographical distribution and biodiversity pattern. Biological data for individual species was gathered from ICLARM (Fishbase) including trophic level and VBGF growth parameters. The temporal and spatial difference between different areas were studied using traditional statistical methods and S-P chart analysis. The results show that Eastern area has higher trophic level , asymptotic length (L¡Û) , maturity length (Lm) , age at maturity (Tm) and Maximum age (Tmax) than the West. Also the Eastern has relatively lower food items on plant , M value and K values. Presence and absence of fish species were organized and presented into the so-called S-P chart for demonstrating the interaction between species or family diversity and habit. Results on family level show that the West has greatest species richness (96 families) in contrast to the North-West and South-East (69 families).A total of 29 families distributed at all areas, whereas fishes belonging to the other 22 families can only be found on one single area. Results on species level show that the West has greatest species richness (538 species) in contrast to the North-West (207 species).Result from the S-P chart also serves for statistical testing in identifying the significance difference on species-habit interactions among different area of fish populations. Cluster analysis show that North-East , East and South-East can be grouped into one group. The other individual groups were North-West , West , South-West , North and South.

Iron-sulfur clusters are protein cofactors that are critical for all life forms. Elaborate multi-component systems have evolved for the biosynthesis of these cofactors to protect organisms from the toxic effects of free iron and sulfide ions. In eukaryotes, the Fe-S cluster assembly machinery operates in the matrix space of the mitochondria and contains a myriad of proteins that mediate sulfur, iron, and electron transfer to assemble Fe-S clusters on the scaffold protein ISCU2 and then distribute these clusters to target proteins. Our lab has recently described stable 3, and 4-protein complexes composed of the cysteine desulfurase NFS1, the co-chaperone ISD11, and ISCU2 (SDU), and NFS1, ISD11, ISCU2, and FXN (SDUF) subunits. In the latter, SDUF, FXN functions as an allosteric activator switching this assembly complex on for Fe-S cluster biosynthesis. Insufficient expression of the mitochondrial protein FXN leads to a progressive neurodegenerative disease, Friedreich's Ataxia (FRDA). In ~2% of patients, FRDA is caused by one of 15 known missense mutations on one allele accompanied by the GAA repeat on the other leading to a complicated phenotype that includes loss of Fe-S clusters. Here we present in vitro evidence that FRDA FXN variants are deficient in their ability to bind the SDU complex, their ability to stimulate the sulfur transfer reaction from NFS1 to ISCU2, and in their ability to stimulate the rate of cluster assembly on ISCU2. Here, in vitro evidence is presented that FXN accelerates the sulfur transfer reaction from NFS1 to ISCU2. Additionally, we present kinetic evidence that identifies the most buried cysteine residue, C104 on ISCU2 as the sulfur acceptor residue suggesting, FXN stabilizes a conformational change to facilitate sulfur delivery. Subsequent mutational studies suggest FXN binding to SDU results in a helix to coil transition in ISCU2 exposing C104 to accept the persulfide sulfur and thereby accelerating the rate of sulfur transfer. We further provide the first biochemical evidence that the persulfide transferred to ISCU2 from NFS1 is viable in Fe-S cluster formation. In contrast to human FXN, the Escherichia coli FXN homolog CyaY has been reported to inhibit Fe-S cluster biosynthesis. To resolve this discrepancy, a series of inter-species enzyme kinetic experiments were performed. Surprisingly, our results reveal that activation or inhibition by the frataxin homolog is determined by which cysteine desulfurase is present and not by the identity of the frataxin homolog. These data are consistent with a model in which the frataxin-less Fe-S assembly complex exists as a mixture of functional and nonfunctional states, which are stabilized by binding of frataxin homologs. Intriguingly, this appears to be an unusual example in which modifications to an enzyme during evolution inverts or reverses the mode of control imparted by a regulatory molecule.

Overweight and obesity in Canada has significantly increased during the last three decades, paralleled by increased intake of fat and sugar particularly sugary beverages leading to higher level of energy intake, as well as reduction in physical activity. Canadian Community Health Survey, Cycle 2.2, 2004 (CCHS 2.2), provides the opportunity to evaluate beverage intakes of Canadians in relation to overweight and obesity using Body Mass Index (BMI).<p> To examine the association between sugar-sweetened beverages and BMI in Canadian adults, we used data from CCHS 2.2 (n=14,304, aged >18 year and <65 year) in which dietary intake was assessed using 24-h recall. In various steps, data on beverage consumption were identified, coded and classified. Using descriptive statistics, we determined total gram intake and the contribution of each beverage to total energy intake among age/sex groups. To determine the most suitable patterns of beverage consumptions among Canadian adults, a cluster analysis K-means method was applied. Males and females were classified into distinct clusters based on the dominant pattern of beverage intakes. Finally, step-wise logistic regression models were used to determine associations between sugar-sweetened beverages and BMI, controlling for age, marital status, income, education, physical activity, total energy intake, immigration status, smoking habits and ethnicity. To account for complex survey design, all data were weighted and bootstrapped.<p> BMI in women with predominant fruit drink pattern (791.1±32.9 g) was significantly higher than those with no dominant pattern in beverage consumption (28.3±1 vs. 26.8±0.3 respectively, P<0.001). In women, high intake of fruit drinks was a significant predictor of overweight (OR=1.84, 95% C.I:1.06-3.20), obesity (OR=2.55, 95% C.I:1.46-4.47) and overweight/obesity (OR=2.05, 95% C.I:1.29-3.25). In men, mean BMI was not different among beverage consumption clusters and none of the beverages was a predictor for overweight and obesity. For the first time, in a nationally representative data, we report association of sugar-sweetened beverages and overweight and obesity in Canadian women.

This project examines the theoretical basis for linking industrial clustering to the strategic management of firms. Specifically, a recently deployed theory building framework defined three perspectives on clustering, the competitiveness perspective, the externalities perspective and the territorial perspective, but stopped short of explaining when, where and to whom these perspectives are relevant. This thesis proposes that firms are the central recipient of cluster effects and that the product-based, resource-based and knowledge-based approaches to management provide the theoretical base from which the operational contexts of each cluster perspective can be defined. Three cluster-management relationships are modelled and beta-tested on a sample of cluster-based firms. The empirical analysis is designed to provide feedback to the theory building process and not to prove or disprove the theory itself.<p> The analysis yielded little if any evidence that the proposed cluster-management relationships are present in the sample that was studied. This result was a surprise as the exuberance with which clusters and their benefits are often promoted suggests that in a cluster there should be a pronounced correlation between firm performance and cluster attributes. The statistical limitations of this analysis mean the results can not be inferred to the general population and that the theoretical propositions are not actually disproved. Nonetheless, the muted observations do cast attention on the need for better modelling and measurement instruments in the field of cluster research. In addition, this project initiates a deductive process by which subsequent research can focus on the causal pathways that comprise the phenomenon of industrial clustering; including the pathway that links clusters to firms and then to economic performance.

Galaxy clusters are powerful tools for studying various astrophysical principles. Gas accreting onto the cluster is heated to 10^7-10^8 K through adiabatic compression and shocks, making clusters highly luminous in X-ray imaging. Measurements of the gas density and temperature profiles can be used to calculate the gas mass fraction f_gas, which is expected to closely match the cosmic baryon fraction Ω_b/Ω_m. Recent observations have found entropy profiles in cluster outskirts that are shallower than predicted and values of f_gas that are higher than the Universal baryon fraction inferred from the Cosmic Microwave Background (CMB). Abell 133 was an ideal candidate for studying this phenomenon, since it had recently been observed in a wide (R≈30') Chandra mosaic with an exposure time of ∼2 Ms. The X-ray imaging was combined with existing optical imaging from the Canada-France-Hawaii Telescope (CFHT) and spectroscopy obtained from the Magellan telescope, to search for any possible gas clumps and to study their properties. The photometric analysis yielded over 3200 red sequence galaxies to a depth of r'=22.5, which were used to create a Gaussian smoothed intensity map and a significance map of the cluster (compared to CFHT Legacy Survey data). About 6 significant overdensities were detected in the significance map, although these did not fully correspond to contours obtained from the X-ray image. Spectroscopy obtained on the cluster yielded ∼700 secure redshifts, of which about 180 were cluster members. This included data from the NOAO Fundamental Plane Survey (NFPS) and the 6 Degree Field Galaxy Survey (6dFGS). We found a cluster redshift of z=0.0561±0.0002 and a velocity dispersion of σ=743±43 km/s. The dynamical analysis gave a virial radius of r_v=1.44±0.03 Mpc and a virial mass of M_v=(5.9±0.8)×10^14 M_sun. We also found values of R_500=1.21±0.07 Mpc and M_500=(5.3±0.9)×10^14 M_sun for γ=1/3 and R_500=0.99±0.05 Mpc and M_500=(2.9±0.5)×10^14 M_sun for γ=1/2, where γ is a parameter related to the assumed density profile and the velocity anisotropy. About 30 overdensities with a radius R_c≥30" were detected as gas clumps on the X-ray image. The galaxy distribution in these clumps was analyzed, both for the stacked signal as well as the individual clumps, in ten parallel colour-magnitude bands to find any significant red sequences associated with them. Most of these clumps appeared to be background systems, some consisting of 1-2 galaxies, others being small groups or clusters. Only 2-3 clumps appeared to be associated with the cluster itself. This suggests that the cluster density profile is actually quite smooth, which may not agree with recent numerical simulations. Further studies are required to determine if the cluster density distribution is consistent with what is predicted and the nature of the background systems.

A día de hoy es prácticamente imposible encontrar una gran institución que no disponga de un parque de ordenadores considerable, debido al alto nivel de informatización de la sociedad actual. El enorme potencial que representan estos miles de ordenadores atrae poderosamente la atención en los ámbitos científicos e industriales, generando opciones viables para su aprovechamiento. Las universidades, instituciones que históricamente se han mantenido a la vanguardia en la investigación e innovación científica, representan un caso especialmente bien posicionado a la hora de generar tanto los recursos informáticos como la necesidad de su uso.El poder de cómputo existente en los laboratorios y aulas de estudio universitarias, agrupaciones naturales de recursos informáticos, crea grandes oportunidades para la computación paralela, animándonos a buscar opciones viables para su aprovechamiento. Como resultado de este interés, nuestro grupo ha creado un entorno de planificación, enfocado hacia los clusters no dedicados. La constante y rápida evolución de los componentes, tanto a nivel de la arquitectura de la CPU como del sistema operativo, así como de las aplicaciones ejecutadas, hace que tengamos que adaptar nuestras propuestas. Nuestra propuesta consiste en crear una Máquina Virtual con doble funcionalidad, ejecutar la carga local de usuario y aprovechar los períodos de inactividad de nodos a efectos de poder usarlos para ejecutar carga paralela. Tanto el tipo de las aplicaciones como las características del hardware del escenario objetivo, y en el momento actual ambas han evolucionado. Nuevos tipos de aplicaciones paralelas con requerimientos periódicos de CPU son cada día más comunes en el mundo científico e industrial. Este tipo de aplicaciones pueden requerir un tiempo de retorno (turnaround) específico o una Calidad de Servicio (Quality of Service, QoS) determinada. Para nuestro caso particular, reviste especial importancia el conocimiento que poseemos de los usuarios locales, debido a que nuestro entorno está diseñado para trabajar en clusters no dedicados. Un usuario local puede estar visualizando un vídeo almacenado en su ordenador, lo cual implica necesidades de CPU periódicas y un mayor uso de memoria. La aparición de nuevos tipos de aplicaciones, como vídeo bajo demanda ó realidad virtual, que se caracterizan por la necesidad de cumplir sus deadlines, presentando requerimientos periódicos de recursos. Este tipo de aplicaciones, donde la pérdida de deadlines no se considera un fallo severo, han sido denominadas en la literatura aplicaciones soft-real time (SRT) periódicas.Esta interesante evolución de las necesidades de los usuarios no es el único digno de atención. El crecimiento en la capacidad de cómputo de los procesadores en los últimos años se ha visto frenado a causa de las barreras físicas del espacio y la velocidad de las señales, obligando a los fabricantes de procesadores a explorar otras vías de crecimiento. Desde hace ya algún tiempo el paralelismo de las aplicaciones se ha convertido en una de las grandes apuestas. Hoy en día los procesadores de dos núcleos son la mínima configuración que encontraremos en un ordenador, y se prevé que el número de núcleos continuará creciendo en los próximos años.Los clusters no dedicados ofrecen un gran potencial de un uso, debido a que los recursos materiales ya están disponibles y el cálculo paralelo se realiza simultáneamente con el del usuario local. Imaginando el escenario actual en los clusters no dedicados, encontramos nuevas aplicaciones de escritorio y paralelas, así como plataformas hardware más potentes y complejas. En esta situación investigar el problema y realizar propuestas relacionadas con la planificación de los diferentes tipos de aplicaciones en clusters no dedicados, considerando las plataformas multicore, supone un nuevo reto a asumir por los investigadores y conforma el núcleo de este trabajo. / Today it is virtually impossible to find an institution that does not have a considerable amount of computers, due to the high level of computerization of society. The enormous potential of these large number of computers attract a lot of attention in science and industry, generating viable options for their use. The universities, institutions that historically have remained at the forefront of research and scientific innovation, represent a case particularly well positioned in generating both, computing resources and the need to use. The computational power present in laboratories and university study rooms, natural groupings of information resources, creating great opportunities for parallel computing, encouraging us to seek viable options for their use. As a result of this interest, our group has created a parallel scheduling environment, focused on non-dedicated clusters. The constant and fast evolution of the components, both at the architecture of the CPU and the operating system and applications executed, forces us to adapt our proposals. Our proposal is to create a Virtual Machine with dual functionality, run the local load user and take advantage of downtime for the purposes of nodes it can be used to run parallel load. At present both, applications and hardware specifications of the target scenario, have evolved. New types of parallel applications with periodic CPU requirements are becoming more common in science and industry. Such applications may require a return time (turnaround) or a specific QoS (Quality of Service). Since our framework is designed to work in non-dedicated clusters, having knowledge of the local users behavior is of particular importance. A local user may be viewing a video stored on your computer, which involves periodic CPU requirements and increased use of memory. The emerging new types of applications, such as video on demand or virtual reality are a fact. This new types of applications are characterized by the need to meet their deadlines, presenting periodic resource requirements. This type of application, where the loss of deadlines is not considered a severe failure, has been named in the literature uses soft-real time (SRT) at regular intervals. This exciting evolution of user needs is not the only one worthy of attention. The growth in computing power of processors in recent years has been hampered because of the physical barriers of space and speed of the signals, forcing chip makers to explore other avenues of growth. For some time the parallelism of the applications has become one of the biggest bets. Today's dual-core processors are the minimum configuration of any computer, and it is expected that the number of nuclei continue to grow in the coming years. The non-dedicated clusters offer great potential for use, because the computational resources are already available, and parallel computing is performed simultaneously with the local user. Figuring out the current scenario in the non-dedicated clusters, we find new desktop applications, parallel and more powerful and complex hardware platforms. In this situation, research lines related to the planning of the different types of applications in non dedicated clusters, considering multi-core platforms, is a new challenge to be assumed by researchers and constitute the core of this work.

La tolerancia a fallos se ha convertido en un requerimiento importante para los ingenieros informáticos y los desarrolladores de software, debido a que la ocurrencia de fallos aumenta el coste de explotación de un computador paralelo. Por otro lado, las actividades realizadas por el mecanismo de tolerancia de fallo reducen las prestaciones del sistema desde el punto de vista del usuario. Esta tesis presenta una arquitectura tolerante a fallos para computadores paralelos, denominada RADIC (Redundant Array of Distributed Fault Tolerance Controllers,), que es simultáneamente transparente, descentralizada, flexible y escalable. RADIC es una arquitectura tolerante a fallos que se basa un controlador distribuido para manejar los fallos. Dicho controlador se basa en procesos dedicados, que comparten los recursos del usuario en el computador paralelo. Para validar el funcionamiento de la arquitectura RADIC, se realizó una implementación que sigue el estándar MPI-1 y que contiene los elementos de la arquitectura. Dicha implementación, denominada RADICMPI, permite verificar la funcionalidad de RADIC en situaciones sin fallo o bajo condiciones de fallo. Las pruebas se han realizado utilizando un inyector de fallos, involucrado en el código de RADICMPI, de manera que permite todas las condiciones necesarias para validar la operación del controlador distribuido de RADIC. También se utilizó la misma implementación para estudiar las consecuencias de usar RADIC en un ambiente real. Esto permitió evaluar la operación de la arquitectura en situaciones prácticas, y estudiar la influencia de los parámetros de RADIC sobre el funcionamiento del sistema. Los resultados probaron que la arquitectura de RADIC funciona correctamente y que es flexible, escalable, transparente y descentralizada. Además, RADIC estableció una arquitectura de tolerancia a fallos para sistemas basados en paso de mensajes. / Fault tolerance has become a major issue for computer engineers and software developers because the occurrence of faults increases the cost of using a parallel computer. On the other hand, the activities performed by the fault tolerance mechanism reduce the performance of the system from the user point of view. This thesis presents RADIC (Redundant Array of Distributed Independent Fault Tolerance Controllers,) a fault-tolerant architecture to parallel computers, which is simultaneously transparent, decentralized, flexible and scalable. RADIC is a fault-tolerant architecture that implements a fully distributed controller to manage faults. Such controller rests on dedicated processes, which share the user's resources in the parallel computer. In order to validate the operation of RADIC, we created RADICMPI, a message-passing implementation that includes the elements of the RADIC architecture and complies with the MPI-1 standard. RADICMPI served for to verifying the functionality of RADIC in scenarios with and without failures in the parallel computer. For the tests, we implemented a fault injector in RADICMPI in order to create the scenarios required to validate the operation of the RADIC distributed controller. We also used RADICMPI to study the practical aspects of using RADIC in a real environment. This allowed us to evaluate the operation of our architecture in practical situations, and to study the influence of the RADIC parameters over the system performance. The results proved that the RADIC architecture operated correctly and that it is flexible, scalable, transparent and decentralized. Furthermore, RADIC established a powerful fault-tolerant architecture model for message-passing systems.