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International audience; Holographic and near-field ptychographic X-ray computed tomography techniques have been compared by characterizing a typical solid oxide cell hydrogen electrode using a high-energy X-ray beam. The main advantages and drawbacks of both methods are discussed regarding the possibility to image the Ni-YSZ cermet, a complex porous electrode microstructure composed of X-ray absorbent materials. The same innovative sub-pixel alignment algorithm, based on tomographic consistency, was applied to align the different tomographic projections for each technique. It has been shown that a better signal-to-noise ratio (SNR) is obtained using nearfield ptychographic tomography, whereas holographic tomography can be faster with similar spatial resolution. Moreover, quantitative electron density maps have been obtained with the two techniques. The quality of the phase identification has also been assessed and compared in both cases using a classical grey-level class separability criterion. After the segmentation, a set of typical microstructural properties describing the electrode morphology was computed. The comparison of the results allowed validating the complementarity of the two Xray imaging techniques. Despite the more time-consuming data acquisition and processing than holographic tomography, near-field ptychographic tomography is especially well adapted to image samples without any insight on their composition or when the sample is highly absorbent. Yet, holographic X-ray tomography, using high-energy X-rays to reduce the sample absorption, remains a faster 3D imaging technique with spatial resolution and contrast sensitivity sufficient for the characterization of solid oxide cell materials.

We evaluated the involvement of the serotonergic system on memory formation and learning processes in healthy adults Wistar rats. Fifty-seven rats of 5 groups had one serotonergic nuclei damaged by an electric current. Electrolytic lesion was carried out using a continuous current of 2mA during two seconds by stereotactic surgery. Animals were submitted to learning and memory tests. Rats presented different responses in the memory tests depending on the serotonergic nucleus involved. Both explicit and implicit memory may be affected after lesion although some groups showed significant difference and others did not. A damage in the serotonergic nucleus was able to cause impairment in the memory of Wistar. The formation of implicit and explicit memory is impaired after injury in some serotonergic nuclei. Resumo Avaliar a participação do sistema serotoninérgico em processos de formação de memória e aprendizagem em ratos Wistar adultos saudáveis. Cinquenta e sete ratos de 5 grupos tinham um núcleo serotoninérgico danificado por uma corrente elétrica. A lesão eletrolítica foi realizada utilizando uma corrente contínua de 2 mA durante dois segundos por cirurgia estereotáxica. Os animais foram submetidos a testes de aprendizagem e memória. Os ratos apresentaram respostas diferentes nos testes de memória, dependendo do núcleo serotoninérgica envolvido. A memória explícita e implícita pode ser afetada após a lesão, embora alguns grupos apresentaram diferença significativa e outros não. A lesão no núcleo serotoninérgico foi capaz de causar danos na memória de Wistar. A formação da memória implícita e explícita é prejudicada após a lesão em alguns núcleos serotoninérgicos.

This study was carried out to select Trichoderma isolates from Amazon forest soil samples, identify their potential for sheath blight (Rhizoctonia solani) suppression in rice, and promote plant growth. Four out of the 13 isolates (T.06, T.09, T.12, T.52) which showed in vitro potential were evaluated through assays under greenhouse conditions utilizing four application methods: 1) preventive and curative sprays; 2) seed treatment + curative sprays; 3) seed treatment; 4) substrate treatment. These four isolates also showed reduced R. solani mycelial growth and sclerotial viability (>50%) and were positive for phosphate solubilization and cellulose degradation. They significantly reduced sheath blight severity when applied as seed treatment, substrate incorporation or foliar spray. However, the preventive and curative sprays were the most efficient method, reducing sheath blight severity by 43% and the area under the disease progress curve by 45%. Isolates T.12 and T.52 applied in substrate treatment increased aerial and root dry weight by 61.2 and 32.9%, respectively. These two isolates showed potential as growth stimulants and can be used as novel biological products and bioinoculants in agriculture for increasing grain yield. RESUMO: Foi realizada a selecao de isolados de Trichoderma spp. provenientes de amostras de solo da Floresta Amazonica e identificado o seu potencial para suprimir a queima da bainha (QB) (Rhizoctonia solani) e para promover o crescimento de plantas de arroz. Quatro de 13 isolados (T.06, T.09, T.12, T.52) que mostraram potencial in vitro foram avaliados em experimentos em casa de vegetacao, utilizando-se quatro metodos de aplicacao: 1) pulverizacao preventiva e curativa; 2) tratamento de semente + pulverizacao curativa; 3) tratamento de semente; 4) tratamento do substrato. Esses quatro isolados, in vitro, reduziram o crescimento micelial de Rhizoctonia solani e a viabilidade do esclerodio (>50%), sendo positivos para solubilizacao de fosforo e degradacao da celulose. Em casa de vegetacao, os quatro isolados reduziram significativamente a severidade da QB quando aplicados via tratamento de semente, incorporados ao substrato e por pulverizacao foliar. Entretanto, a pulverizacao preventiva + curativa foi mais eficiente, reduzindo em 43% a severidade da QB e em 45% a area sob curva de progresso da doenca. Os T.12 e T.52 aplicados via substrato promoveram o incremento em massa seca da parte aerea e radicular em 61,2 e 32,9%, respectivamente. Esses dois isolados mostraram potencial como promotores do crescimento e poderao ser usados como novo produto biologico e bioinoculantes na agricultura para aumento de produtividade. Rice sheath blight biocontrol and growth promotion by Trichoderma isolates from the Amazon Biocontrole da queima da bainha em arroz e promocao do crescimento por isolados de Trichoderma da Amazonia Joseani Castro da Silva1 Darlyne Barros Torres1 Denise Castro Lustosa2 Marta Cristina Corsi de Filippi3 Gisele Barata da Silva1* 1Universidade Federal Rural da Amazonia – UFRA, Pres. Tancredo Neves, 2501, 66077-530, Belem, PA, Brasil 2Universidade Federal do Oeste do Para – UFOPA, Instituto de Biodiversidade e Florestas – IBF, Vera Paz, Sales, 68035-110, Santarem, PA, Brasil 3Embrapa Arroz e Feijao, CP 179, 75375-000, Santo Antonio de Goias, GO, Brasil Autor Correspondente: *E-mail: gisele.barata@ufra.edu.br

The Compact Muon Solenoid (CMS) experiment is currently installing upgrades to their Calorimeter Trigger for LHC Run 2 to ensure that the trigger thresholds can stay low, and physics data collection will not be compromised. The electronics will be upgraded in two stages. Stage-1 for 2015 will upgrade some electronics and links from copper to optical in the existing calorimeter trigger so that the algorithms can be improved and we do not lose valuable data before stage-2 can be fully installed by 2016. Stage-2 will fully replace the calorimeter trigger at CMS with a micro-TCA and optical link system. It requires that the updates to the calorimeter back-ends, the source of the trigger primitives, be completed. The new systemâ??s boards will utilize Xilinx Virtex-7 FPGAs and have hundreds of high-speed links operating at up to 10 Gbps to maximize data throughput. The integration, commissioning, and installation of stage-1 in 2015 will be described, as well as the integration and parallel installation of the stage-2 in 2015, for a fully upgraded CMS calorimeter trigger in operation by 2016.Solenoid (CMS) experiment is currently installing an upgrade to their Calorimeter Trigger to ensure that the trigger thresholds can stay low, and physics data collection will not be compromised by these challenging conditions. The electronics will be upgraded in two stages. Stage-1 will upgrade some electronics and links from copper to optical in the existing calorimeter trigger so that the algorithms can be improved and we do not lose valuable data before Stage-2 can be fully installed. Stage-2 will fully replace the calorimeter trigger at CMS with a micro-TCA and optical link system, and require that the updates to the calorimeter back-ends, the source of the trigger primitives, are completed. The new systemâ??s boards will utilize Xilinx Virtex 7 FPGAs and have hundreds of high-speed links operating at up to 10 Gbps to maximize data throughput. The integration, commissioning, and installation of stage-1 in 2015 will be described, as well as the integration and parallel installation of the stage-2 in 2015, for an fully upgraded CMS calorimeter trigger in operation by 2016.

The data concentrator card (DCC) is part of the readout electronics of a particle physics detector. The DCC project is a multi-project project involving high-speed design, built-in testability, data processing with data reduction techniques, low-jitter clock distribution, power supply regulation and filtering and implementation of multiple FPGAs on a 9U multilayer printed circuit board. The DCC collects data from various sources and after processing transmits the resulting data to a central data acquisition system (DAQ). The validation of the DCC required the design of a specific test system that emulates the detector functionality. To cover all the experiment needs we had to produce 60 similar boards. In this paper we summarize the design architecture and functionality of the DCC, the developed test bench and present the production status.

The search for unknown frequent pattern is one of the core activities in many time series data mining processes. In this paper we present an extension of the pattern discovery problem in two directions. First, we assume data to be distributed among various participating peers, and require overhead communication to be minimized. Second, we allow the participating peer to be malicious, which means that we have to address privacy issues. We present three problems along with algorithms to solve them. They are presented in increasing order of complexity according to the extensions we are pursuing, i.e. distribution and privacy constraints. As the main result we present our secure multiparty protocol for the privacy preserving pattern discovery problem.

The electromagnetic calorimeter of the CMS experiment at CERN is an homogeneous calorimeter made of about 80000 Lead Tungstate crystals, that will start to operate at the LHC at the end of 2007. From June to November 2006, ten barrel Supermodules (1700 crystals each) were exposed to beam at CERN SPS, both in standalone and in association with portions of the Hadron Calorimeter. We present the description of the system used to configure and readout the calorimeter during the campaign. The full set of final readout electronics boards was employed, together with the pre-series version of the data acquisition software. During the campaign, the hardware and software concepts for the final system were validated. The system allowed the intercalibration of the ten Supermodules and allowed to perform several important studies of the detector performances, such as energy resolution, response linearity and radiation-hardness.

The CMS experiment uses information from its electromagnetic and hadronic calorimeters and muon detectors to decide whether to readout the whole detector. For such a task to be successful, all trigger primitives pushed through the trigger decision tree must be flawlessly aligned in time for operation at 40 MHz. Both calorimeters in CMS use the Synchronization Link Board for this purpose. In this article we report on the results of tests of this board using realistic beam conditions, which demonstrate the soundness of the adopted architecture and synchronization principle.

The CMS Preshower is a fine grain detector that comprises 4288 silicon sensors, each containing 32 strips. The raw data are transferred from the detector to the counting room via 1208 optical fibres. Each fibre carries a 600-byte data packet per event. The maximum average level-1 trigger rate of 100 kHz results in a total data flow of similar to 72 GB/s from the Preshower. For the readout of the Preshower, 56 links to the CMS DAQ have been reserved, each having a bandwidth of 200 MB/s (2 kB/event). The total available downstream bandwidth of similar to 11 GB/s necessitates a reduction in the data volume by a factor of at least 7. A modular VME-based system is currently under development. The main objective of each VME board in this system is to acquire on-detector data from at least 22 optical links, perform on-line data reduction and pass the concentrated data to the CMS DAQ. The principle modules that the system is based on are being developed in collaboration with the TOTEM experiment. Ieee Transactions on Nuclear Science

The number of artifacts used and generated by the software development process can be meaningful. However, as specifications evolve towards source code, the connection between them is often lost transforming software maintenance into a difficult and time-consuming task, further hindered by the lack of good documentation. To help organize generated artifacts and maintain a historical overview of the process, a tool is being specified that uses ontologies to combine real world domain information and software engineering knowledge, to produce up-to-date documentation that evolves along time.

This paper presents a self-resonant PWM full-bridge DC to DC converter operating at reduced conduction and commutation losses working with three different transformers and using phase-shift control. This converter employs a self-resonant circuit and a tapped inductor for minimizing a circulating current flowing through the transformer and switching devices. The principle of the self-resonant circuit provides the soft switching. It is based on an auxiliary voltage source that feeds the resonant circuit, charging a capacitor which provides the condition for zero voltage switching (ZVS) of the main switches. The proposed approach allows building a converter with high frequency of operation. A detailed analysis of the operation is presented. The output voltage is controlled by PWM. The complete theoretical analysis, operating principles, simulation and experimental results are presented.

This paper presents a series resonant PWM full-bridge DC-DC power converter operating at reduced conduction and commutation losses working with three different transformers and using phase-shift control. This power converter employs a self-resonant circuit and a tapped inductor for minimizing circulating current flow through the transformer and switching devices. The principle of the self-resonant circuit provides the soft switching. It is based in an auxiliary voltage source that feeds the resonant circuit, charging a capacitor which provides the condition for zero voltage switching (ZVS) of the main switches. The proposed approach allows the construction of a power converter with high frequency of operation. A detailed analysis of the operation is presented. The output voltage is controlled by PWM. The complete theoretical analysis, operating principles, simulation and experimental results are presented.

Boolean neural networks are known for their low cost and ease of hardware implementation. Networks of goal seeking neurons (GSN) encompasses an interesting class and were designed to solve problems from networks of probabilistic logic neurons (PLN), successors of the very first Boolean model. The use of neural networks in financial applications is being consolidated through the last decade. This paper proposes a GSN based system to cope with ranking problems. We are concerned with the ranking of clients with respect to financial solvency. On the contrary of more popular models, GSN networks have a one-shot learning algorithm (where each example is shown only once) combined with the nondestruction of acquired knowledge. These features lead to inability to learn nonrepresentative patterns and show it is possible to define the similarity degree of a client with respect to the whole class. The proposed system aims, therefore, to define how solvent and insolvent a client is in relation to the universe of classified clients presented to the network. The proposed system also implements earlier research on the treatment of false examples by GSN control of presentation order.

This work is the result of a collaboration between INESC and LIP in the CMS experiment being conducted at CERN. The collaboration addresses the application of boundary scan test at system level namely the development of a VME boundary scan controller (BSC) board prototype and the corresponding software. This prototype uses the MTM bus existing in the VME64/spl times/ backplane to apply the 1149.1 test vectors to a system composed of nineteen boards, called here units under test (UUTs). A top-down approach is used to describe our work. The paper begins with some insights about the experiment being conducted at CERN, proceed with system level considerations concerning our work and with some details about the BSC board. The results obtained so far and the proposed work is reviewed in the end of this contribution.

A prototype of the trigger and digital processing electronics for the electromagnetic calorimeter of the CMS experiment, coupled to a prototype of the PbWO4 crystal calorimeter, was tested during summer 1996 in the H4 beamline at the CERN SPS. A very successful operation was achieved for this system, which runs in synchronous and pipelined mode at the LHC clock frequency, and performs the basic trigger and data acquisition functions needed in the CMS electromagnetic calorimeter. The performance of the trigger front-end electronics is well within the established requirements: a highly efficient bunch-crossing identification (>99.9%), a good trigger-energy resolution ( σ/E∼9%/ E ⊕2% ) and a highly efficient electron cluster shape identification (∼99%) have been achieved. The FERMI digitising system based on a dynamic analog compressor and a sampling ADC showed a very good performance, in particular the energy resolution for 150 GeV electrons was 0.54%, equal to the resolution obtained with a conventional charge integration ADC system.

At the Large Hadron Collider at CERN the proton bunches cross at a rate of 40MHz. At the Compact Muon Solenoid experiment the original collision rate is reduced by a factor of O (1000) using a Level-1 hardware trigger. A subsequent factor of O(1000) data reduction is obtained by a software-implemented High Level Trigger (HLT) selection that is executed on a multi-processor farm. In this review we present in detail prototype CMS HLT physics selection algorithms, expected trigger rates and trigger performance in terms of both physics efficiency and timing., Comment: accepted by EPJ Nov 2005