Geminivirus Rep Protein Interferes with the Plant DNA Methylation Machinery and Modifies the Host Epigenome

The apparent simplicity of viruses hides the complexity of their interactions with their hosts. Viruses are masters at circumventing host defenses and manipulating the cellular environment for their own benefit. The replication of the largest known family of single-stranded DNA viruses, Geminiviridae, is impaired by DNA methylation and Arabidopsis mutants affected in cytosine methylation are hypersusceptible to geminivirus infection. This implies that plants might use methylation as a defense against geminiviruses and that the viral genome is a target for plant DNA methyltransferases. We have found a novel counter-defense strategy used by geminiviruses, that reduces the expression of the plant maintenance DNA methyltransferases, MET1 and CMT3, in both, locally and systemically infected tissues. Furthermore, we demonstrated that the virus-mediated repression of these two maintenance DNA methyltransferases is widely spread among different geminivirus species. Additionally, we identified Rep as the geminiviral protein responsible for the repression of MET1 and CMT3, and another viral protein, C4, as an ancillary player in MET1 downregulation. The presence of Rep, suppresses TGS of an Arabidopsis transgene and of host loci whose expression is strongly controlled by CG methylation. Bisulfite sequencing analyses showed that the expression of Rep caused a substantial reduction in the levels of DNA methylation at CG sites. Our findings suggest that Rep, the only viral protein essential for geminiviral replication, displays TGS suppressor activity through a mechanism distinct from the one thus far described for geminiviruses.

Technology, mining methods and landscapes of a placer mining district in Fairbanks, Alaska, 1900-1930

Placer miners in Alaska’s interior were part of the last great gold rush in North America. As word of gold in the Fairbanks Mining District traveled down the Yukon River, a wave of miners from the Klondike placer fields in Dawson, along with a assortment of speculators and inexperienced green horns from the Lower 48 converged on the confluence of the Tanana and Chena rivers hoping to strike it rich. The steamers coming from Dawson were integral; they carried miners with experience working the frozen subarctic placer deposits of the Klondike. These miners encountered new environmental challenges that required the development of new technologies and mining methods to efficiently harvest gold. These methods and machines were brought into Fairbanks and further perfected to account for the local conditions. This thesis describes the local mining technologies and methods employed in the Fairbanks district and the landscape patterns created during the placer mining boom years of 1903-1909, decline years of 1910-1923 and recovery of 1923-1930.

Calibration of the maximum carboxylation velocity (Vcmax) using data mining techniques and ecophysiological data from the Brazilian Semiarid region, for use in Dynamic Global Vegetation Models.

The semiarid region of northeastern Brazil, the Caatinga, is extremely important due to its biodiversity and endemism. Measurements of plant physiology are crucial to the calibration of Dynamic Global Vegetation Models (DGVMs) that are currently used to simulate the responses of vegetation in face of global changes. In a field work realized in an area of preserved Caatinga forest located in Petrolina, Pernambuco, measurements of carbon assimilation (in response to light and CO2) were performed on 11 individuals of Poincianella microphylla, a native species that is abundant in this region. These data were used to calibrate the maximum carboxylation velocity (Vcmax) used in the INLAND model. The calibration techniques used were Multiple Linear Regression (MLR), and data mining techniques as the Classification And Regression Tree (CART) and K-MEANS. The results were compared to the UNCALIBRATED model. It was found that simulated Gross Primary Productivity (GPP) reached 72% of observed GPP when using the calibrated Vcmax values, whereas the UNCALIBRATED approach accounted for 42% of observed GPP. Thus, this work shows the benefits of calibrating DGVMs using field ecophysiological measurements, especially in areas where field data is scarce or non-existent, such as in the Caatinga

Issues in autonomous navigation of underground vehicles

This paper describes current research at the Australian Centre for Field Robotics (ACFR) in collaboration with the Commonwealth Scientific and Industrial Research Organisation (CSIRO) within the Cooperative Research Centre (CRC) for Mining Technology and Equipment (CMTE) towards achieving autonomous navigation of underground vehicles, like a Load-Haul-Dump (LHD) truck. This work is being sponsored by the mining industry through the Australian Mineral Industries Research Association Limited (AMIRA). Robust and reliable autonomous navigation can only be realised by achieving high level tasks such as path-planning and obstacle avoidance. This requires determining the pose (position and orientation) of the vehicle at all times. A minimal infrastructure localisation algorithm that has been developed for this purpose is outlined and the corresponding results are presented. Further research issues that are under investigation are also outlined briefly.

Automation of underground truck haulage

This paper reviews the state-of-the art in the automation of underground truck haulage. Past attemps at automating LHDs and haul trucks are described and their particular strengths and weaknesses are listed. We argue that the simple auto-tram...

Case study: Dragline swing to dump automation

Dragline Swing to Dump Automation By Peter Corke, CSIRO Manufacturing Technology/CRC for Mining Technology and Equipment (CMTE) Peter Corke presented a case study of a project to automate the dragline swing to dump operation. The project is funded by ACARP, BHP Coal, Pacific Coal and the CMTE and is being carried out on a dragline at Pacific Coal's Meandu mine near Brisbane. Corke began by highlighting that the minerals industry makes extensive use of large, mechanised machines. However, unlike other industries, mining has not adopted automation and most machines are controlled by human operators on board the machine itself. Choosing an automation target The dragline automation was chosen because: ò draglines are one of the biggest capital assets in a mine; ò performance between operators vary significantly, so improved capital utilisation is possible; ò the dragline is often the bottleneck in production; ò a large part of the operation cycle is spent swinging from dig to dump; and ò it is technically feasible. There has been a history of drag line automation projects, none with great success.

Dragline automation

Draglines are used extensively for overburden stripping in Australian open cut coal mines. This paper outlines the design of a computer control system to implement an automated swing cycle on a production dragline. Subsystems and sensors have been developed to satisfy the constraints imposed by the task, the harsh operating environment and the mines production requirements.

Innovación, capacidad productiva, formación en el puesto de trabajo y productividad

[ES] Este estudio analiza la relación entre productividad laboral, innovación radical, innovación incremental, tecnología incorporada en maquinaria y equipos, utilización de la capacidad productiva y formación. Los datos utilizados son de empresas españolas, manufactureras y de servicios, procedentes de la Business Environment and enterprise Performance Survey (BEEPS). La técnica empleada para estimar los coeficientes del modelo es la regresión mínimo cuadrática ordinaria, ya que la variable dependiente (productividad laboral) es continua. Los resultados indican que la innovación radical y la formación influyen positiva y significativamente sobre la productividad laboral. La influencia de la tecnología incorporada también es significativa, pero de signo negativo. Finalmente, señalar que las empresas que más exportan y las de mayor tamaño alcanzan mayores niveles de productividad. Los hallazgos encontrados en este estudio tienen implicaciones para los responsables de la política económica. Los decisores políticos españoles deben promover y subsidiar la adquisición de maquinaria y equipos más eficientes para las empresas que alcanzan menores niveles de productividad, así como subsidiar la formación de trabajadores cualificados en el manejo de estos nuevos equipos. Además, también deben promover y subsidiar el desarrollo de actividades de elevado contenido en I+D para las empresas que consiguen elevados niveles de productividad, a fin de que incrementen su desempeño en innovación radical. La promoción y subsidiación de programas de formación relacionados con la I+D también resulta esencial en este tipo de empresas, máxime en un escenario caracterizado por un cambio tecnológico intenso y que se produce con gran rapidez.

A guide to the fisheries of Ceylon

This bulletin has been written primarily to serve as a handbook to the Indo-Pacific Fisheries Council at its sessions in Colombo during December 1958. It presents an outline of the fishing industry as found in Ceylon today, in non-technical language so that it may also be understood by laymen. The large gaps in our knowledge are brought out in the section on "resources"; the section on "administration" gives an indication of progress made towards solving the problems of the industry, while sections on "fishing methods" and "utilization of catch" will help us to appreciate the handicaps and difficulties of those concerned with the industry. The Government Administration of the fisheries of Ceylon is being assisted to a considerable extent by the generous gifts of machinery and equipment as well as the loan of skilled technical personnel made by other countries through the FAO and the Colombo Plan. The progress made so far has helped to place the industry in a favorable position for further improvements.

Numerical modelling of laboratory tests for TBM cutter indentation process analysis

Considering that TBMs are nowadays used for long Trans-Alpine tunnels, the
understanding of rock breaking and chipping due to TBM cutter disks mechanism, for deep tunnelling operations, becomes very interesting. In this paper, the results from carried out laboratory tests that simulate the disk cutter action at the rock tunnel face by means of an indentation tool, acting on a rock
specimen with proper size, and the related three-dimensional and two-dimensional numerical modelling are proposed. The developed numerical models simulate the different test conditions (applied load, boundary conditions) allowing the analysis of the stresses distributions along possible breaking planes.
The influence of a confinement-free area on one side of the specimen, simulating the formation of a groove near the tool, is pointed out.
The obtained results from numerical modelling put in evidence a satisfactory agreement with the experimental observations.

Optimization of export support systems

The present paper is a personal reflection on a work project carried out to promote exports from Portugal to Germany in the IT area, under consideration of the deliverables required by the clients CCILA and Anetie. The project outcome approaches the fact that the majority of the Portuguese market players has disadvantages in size and does rarely coordinate activities among each other, which hinders them to export successfully on a broad scale. To bring together Portuguese delivery potential and German market demand, expert interviews were conducted. Based on the findings, a concept was developed to overcome the domestic collaboration issues in order to strengthen the national exports in the identified sector - embedded systems implementation services for machinery and equipment companies.

Perfil logístico de Colombia

El presente documento ofrece un estudio del perfil logístico de Colombia con la finalidad de dar a conocer el estado de arte de las ciudades, puertos e infraestructura principal para facilitar la toma de decisiones de los empresarios. Para el desarrollo de este trabajo se determinaron a partir de un análisis competitivo del país; las principales ciudades y puertos; logrando establecer un inventario de maquinaria y equipo e infraestructura logística; enmarcados en retos ya establecidos en las políticas públicas.

Estudio de caso: estrategias internacionales aplicadas a la empresa Astro Maquinaria Ltda.

En el estudio de caso se podrá encontrar información relacionada a la empresa ASTRO MAQUINARIA Ltda. la cual lleva más de 20 años en el mercado, generando soluciones a las necesidades de maquinaria y equipos, especialmente en el área de bombeo. Desde el principio la empresa ha estado importando desde Estados Unidos el portafolio de productos que ofrecen, actualmente tienen la representación comercial de la empresa Pentair Pump Group. Este estudio de caso pretende identificar cual es la estrategia de internacionalización empleada por la empresa, la toma de decisiones, la cadena de abastecimiento, relaciones comerciales, entre otras; las cuales han logrado la perdurabilidad y el crecimiento de la empresa desde su inicio. La metodología utilizada para el desarrollo de este estudio de caso se basara en variables cualitativas que permiten el análisis profundo y la indagación sobre el fenómeno, igualmente se utilizaran algunas variables cuantitativas para observar la situación actual de la empresa y el desempeño de la misma en el sector de comercialización de maquinaria pesada.

Diagnostic de securite d'une entreprise bresilienne a partir de l'analyse des accidents du travail par la methode de l'arbre des causes

We present here the results of a study of 21 work-related accidents that occurred in a Brazilian manufacturing company. The aim was to assess the safety level of the company to improve its work accident prevention policy. In the last 6 months of 1992 and 1993, all accidents resulting in 15 days' absence from work, reported for social security purposes, were analyzed using the INRS causal tree method (ADC) and a questionnaire completed on site. Potential risk factors for accidents were identified based on the specific factors highlighted by the ADC. More universal trees were also compiled for the safety assessment. Three hundred and thirty specific accident factors were recorded (man of 15.71 per accident). This is consistent with there being multiple causes of accidents rather than the assertion of Brazilian business safety departments that accidents are due to 'dangerous' or 'unsafe' behavior. Introducing the idea of culpability into accidents prevents the implementation of an appropriate information feedback process, essential for effective prevention. However, the large number of accidents related to 'material' (78%) and 'environment' (70%) indicates that working conditions are poor. This shows that the technical risks, mostly due to unsafe machinery and equipment are not being dealt with. Seventy-five potential accident factors were identified. Of these, 35% were 'organizational', a high proportion for the company studied. Improvisation occurs at all levels, particularly at the organizational level. This is, thus a major determinant for entire series of, if not most, accident situations. The poor condition of equipment also plays a major role in accidents. The effects of poor equipment on safety exacerbate the organizational shortcomings. The company's safety intervention policy should improve the management of human resources (rules designating particular workers for particular workstations; instructions for the safe operation of machines and equipment; training of operators, etc.) and introduce programs to detect risks and to improve the safety of machines and equipment. We also recommend the establishment of a program to follow the results of any preventive measures adopted.

Diagnostic de sécurité d’une entreprise brésilienne à partir de l’analyse des accidents du travail par la méthode de l’arbre des causes

We present here the results of a study of 21 work-related accidents that occurred in a Brazilian manufacturing company. The aim was to assess the safety level of the company to improve its work accident prevention policy. In the last 6 months of 1992 and 1993, all accidents resulting in 15 days' absence from work, reported for social security purposes, were analyzed using the INRS causal tree method (ADC) and a questionnaire completed on site. Potential risk factors for accidents were identified based on the specific factors highlighted by the ADC. More universal trees were also compiled for the safety assessment. Three hundred and thirty specific accident factors were recorded (mean of 15.71 per accident). This is consistent with there being multiple causes of accidents rather than the assertion of Brazilian business safety departments that accidents are due to dangerous or unsafe behavior. Introducing the idea of culpability into accidents prevents the implementation of an appropriate information feedback process, essential for effective prevention. However, the large number of accidents related to material (78%) and environment (70%) indicates that working conditions are poor. This shows that the technical risks, mostly due to unsafe machinery and equipment are not being dealt with. Seventy-five potential accident factors were identified. Of these, 35% were organizational, a high proportion for the company studied. Improvisation occurs at all levels, particularly at the organizational level. This is thus a major determinant for entire series of, if not most, accident situations. The poor condition of equipment also plays a major role in accidents. The effects of poor equipment on safety exacerbate the organizational shortcomings. The company's safety intervention policy should improve the management of human resources (rules designating particular workers for particular workstations; instructions for the safe operation of machines and equipment; training of operators, etc.) and introduce programs to detect risks and to improve the safety of machines and equipment. We also recommend the establishment of a program to follow the results of any preventive measures adopted.