575 research outputs found

    Fast Matrix Multiplication via Compiler-only Layered Data Reorganization and Intrinsic Lowering

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    The resurgence of machine learning has increased the demand for high-performance basic linear algebra subroutines (BLAS), which have long depended on libraries to achieve peak performance on commodity hardware. High-performance BLAS implementations rely on a layered approach that consists of tiling and packing layers, for data (re)organization, and micro kernels that perform the actual computations. The creation of high-performance micro kernels requires significant development effort to write tailored assembly code for each architecture. This hand optimization task is complicated by the recent introduction of matrix engines by IBM's POWER10 MMA, Intel AMX, and Arm ME to deliver high-performance matrix operations. This paper presents a compiler-only alternative to the use of high-performance libraries by incorporating, to the best of our knowledge and for the first time, the automatic generation of the layered approach into LLVM, a production compiler. Modular design of the algorithm, such as the use of LLVM's matrix-multiply intrinsic for a clear interface between the tiling and packing layers and the micro kernel, makes it easy to retarget the code generation to multiple accelerators. The use of intrinsics enables a comprehensive performance study. In processors without hardware matrix engines, the tiling and packing delivers performance up to 22x (Intel), for small matrices, and more than 6x (POWER9), for large matrices, faster than PLuTo, a widely used polyhedral optimizer. The performance also approaches high-performance libraries and is only 34% slower than OpenBLAS and on-par with Eigen for large matrices. With MMA in POWER10 this solution is, for large matrices, over 2.6x faster than the vector-extension solution, matches Eigen performance, and achieves up to 96% of BLAS peak performance

    O PÊNDULO DEFASADO: um exemplo de sistema caótico para estudantes do ciclo inicial do curso de graduação em Física

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    Neste trabalho é apresentado um estudo realizado por estudantes ingressantes do curso de Física da Universidade Federal do Pará com o objetivo de se analisar os estados de estabilidade de um pêndulo cujo pivô está em movimento circular uniforme (MCU). O modelo teórico foi desenvolvido utilizando-se a descrição de Lagrange da Mecânica Clássica. Após a modelagem, comparou-se as previsões teóricas com um aparato experimental, afim de se observar os casos de estabilidade. O projeto foi desenvolvido em uma disciplina piloto que se utilizou de uma metodologia ativa, baseada na indagação, em particular com o uso de problemas em aberto, para desenvolver nos estudantes habilidades e competências ligadas ao processo investigativo em ciências exatas, contribuindo também indiretamente para o entendimento da natureza da ciências

    An SFC-enabled approach for processing SSL/TLS encrypted traffic in future enterprise networks

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    In this paper, we propose an architecture based on NFV and SDN which allows to balance traffic analysis techniques using a Classifier. It steers flows to the appropriate Service Function Chaining (to open traffic or not) according to network requirements (such as, effectiveness, flexibility, scalability, performance, and privacy). The SSL/TLS traffic processing is carried-out by the centerpiece of this work, the SFC-enabled MITM. A Proof-of-Concept was conducted (focusing on our SFC-enabled MITM) which showed that functionalities lost due to encryption (Content Optimization, Caching, Network Anti-virus, and Content Filter) were recovered when processing opened traffic within its Service Function Chains. We also evaluated its impact on performance. The results show that cipher suite overhead plays a role but can be mitigated, the Classifier can alleviate the performance overhead of different traffic analysis techniques, network functions have lower impact to performance, and Service Function Chaining length influences page load time.publishe

    Orchestrating an SFC-enabled SSL/TLS traffic processing architecture using MANO

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    The heterogeneity of 5G requirements commands more complex network architectures, imposing the need for network orchestration. ETSI NFV MANO is the standard which defines a common framework for vendors and operators to integrate their orchestration efforts. In this paper, we evaluated how an ETSI NFV MANO compliant orchestrator (OSM) fares while orchestrating an SFC-enabled SSL/TLS encrypted traffic processing architecture, which supports both edge and cloud deployments. A quantitative evaluation was carried-out, which assessed the responsiveness and overheads of OSM, as well as the actual functionality of our SSL/TLS processing architecture (with edge computing components). A qualitative evaluation was also carried-out, providing insight into the maturity of the current OSM release, what works well, what requires workarounds, and the actual limitations. A demonstration of the architecture evaluated in this work was accepted as a contribution to the ETSI OSM PoC Framework.publishe

    Avaliação do estado nutricional de agroecossistemas de café orgânico no estado de Minas Gerais.

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    A produção de café orgânico vem se constituindo uma tendência necessária e irreversível do agronegócio brasileiro. Essa atividade tem-se destacado como uma alternativa de renda para alguns cafeicultores, devido à crescente demanda mundial por alimentos mais saudáveis. Entretanto, grande parte das técnicas propostas pela agricultura orgânica está sendo aplicada empiricamente no cultivo de café, principalmente no Estado de Minas Gerais, maior região produtora de café do Brasil. Levando-se em consideração a baixa fertilidade natural dos solos dessa região cafeeira, bem como a elevada extração de nutrientes pelo cafeeiro, objetivou-se neste trabalho identificar possíveis fatores limitantes para a produção orgânica do cafeeiro, relacionados à fertilidade do solo e ao estado nutricional das plantas. Foram realizadas avaliações da fertilidade do solo e análise das folhas em vinte e uma lavouras orgânicas representativas do Estado de Minas Gerais. As amostras de solo foram analisadas para determinação do pH, acidez potencial e dos teores de P, K, Ca, Mg, S, Al e matéria orgânica. As amostras foliares foram analisadas para determinação dos teores de N, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn. Com base nos padrões de interpretação para cafeeiros convencionais propostos pela literatura, estabeleceram-se as freqüências com que os caracteres analisados foram inferiores aos critérios de interpretação da fertilidade do solo e estado nutricional das plantas. A análise dos dados foi realizada por estatística descritiva. Novos trabalhos nessa nova área são necessários, visando a uma melhor interpretação da análise foliar e da fertilidade do solo, quando se trabalha com café orgânico

    Coronarin D induces apoptotic cell death and cell cycle arrest in human glioblastoma cell line

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    Glioblastoma (GBM) is the most frequent and highest–grade brain tumor in adults. The prognosis is still poor despite the use of combined therapy involving maximal surgical resection, radiotherapy, and chemotherapy. The development of more efficient drugs without noticeable side effects is urgent. Coronarin D is a diterpene obtained from the rhizome extract of Hedychium coronarium, classified as a labdane with several biological activities, principally anticancer potential. The aim of the present study was to determine the anti–cancer properties of Coronarin D in the glioblastoma cell line and further elucidate the underlying molecular mechanisms. Coronarin D potently suppressed cell viability in glioblastoma U–251 cell line, and also induced G1 arrest by reducing p21 protein and histone H2AX phosphorylation, leading to DNA damage and apoptosis. Further studies showed that Coronarin D increased the production of reactive oxygen species, lead to mitochondrial membrane potential depolarization, and subsequently activated caspases and ERK phosphorylation, major mechanisms involved in apoptosis. To our knowledge, this is the first analysis referring to this compound on the glioma cell line. These findings highlight the antiproliferative activity of Coronarin D against glioblastoma cell line U–251 and provide a basis for further investigation on its antineoplastic activity on brain cancer.This research was funded by grants from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP 2014/06636–7 and 2016/06137–6), financiadora de Estudos e Projetos FINEP (MCTI/FINEP/MS/SCTIE/DECIT–01/2013–FPXII–BIOPLAT)

    A Rapid and Simple Procedure for the Establishment of Human Normal and Cancer Renal Primary Cell Cultures from Surgical Specimens

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    The kidney is a target organ for the toxicity of several xenobiotics and is also highly susceptible to the development of malignant tumors. In both cases, in vitro studies provide insight to cellular damage, and represent adequate models to study either the mechanisms underlying the toxic effects of several nephrotoxicants or therapeutic approaches in renal cancer. The development of efficient methods for the establishment of human normal and tumor renal cell models is hence crucial. In this study, a technically simple and rapid protocol for the isolation and culture of human proximal tubular epithelial cells and human renal tumor cells from surgical specimens is presented. Tumor and normal tissues were processed by using the same methodology, based on mechanical disaggregation of tissue followed by enzymatic digestion and cell purification by sequential sieving. The overall procedure takes roughly one hour. The resulting cell preparations have excellent viabilities and yield. Establishment of primary cultures from all specimens was achieved successfully. The origin of primary cultured cells was established through morphological evaluation. Normal cells purity was confirmed by immunofluorescent staining and reverse transcription-polymerase chain reaction analysis for expression of specific markers

    Prime Focus Spectrograph - Subaru's future -

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    The Prime Focus Spectrograph (PFS) of the Subaru Measurement of Images and Redshifts (SuMIRe) project has been endorsed by Japanese community as one of the main future instruments of the Subaru 8.2-meter telescope at Mauna Kea, Hawaii. This optical/near-infrared multi-fiber spectrograph targets cosmology with galaxy surveys, Galactic archaeology, and studies of galaxy/AGN evolution. Taking advantage of Subaru's wide field of view, which is further extended with the recently completed Wide Field Corrector, PFS will enable us to carry out multi-fiber spectroscopy of 2400 targets within 1.3 degree diameter. A microlens is attached at each fiber entrance for F-ratio transformation into a larger one so that difficulties of spectrograph design are eased. Fibers are accurately placed onto target positions by positioners, each of which consists of two stages of piezo-electric rotary motors, through iterations by using back-illuminated fiber position measurements with a wide-field metrology camera. Fibers then carry light to a set of four identical fast-Schmidt spectrographs with three color arms each: the wavelength ranges from 0.38 {\mu}m to 1.3 {\mu}m will be simultaneously observed with an average resolving power of 3000. Before and during the era of extremely large telescopes, PFS will provide the unique capability of obtaining spectra of 2400 cosmological/astrophysical targets simultaneously with an 8-10 meter class telescope. The PFS collaboration, led by IPMU, consists of USP/LNA in Brazil, Caltech/JPL, Princeton, & JHU in USA, LAM in France, ASIAA in Taiwan, and NAOJ/Subaru.Comment: 13 pages, 11 figures, submitted to "Ground-based and Airborne Instrumentation for Astronomy IV, Ian S. McLean, Suzanne K. Ramsay, Hideki Takami, Editors, Proc. SPIE 8446 (2012)
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