Approximating Hit Rate Curves using Streaming Algorithms

A hit rate curve is a function that maps cache size to the proportion of requests that can be served from the cache. (The caching policy and sequence of requests are assumed to be fixed.) Hit rate curves have been studied for decades in the operating system, database and computer architecture communities. They are useful tools for designing appropriate cache sizes, dynamically allocating memory between competing caches, and for summarizing locality properties of the request sequence. In this paper we focus on the widely-used LRU caching policy. Computing hit rate curves is very efficient from a runtime standpoint, but existing algorithms are not efficient in their space usage. For a stream of m requests for n cacheable objects, all existing algorithms that provably compute the hit rate curve use space linear in n. In the context of modern storage systems, n can easily be in the billions or trillions, so the space usage of these algorithms makes them impractical. We present the first algorithm for provably approximating hit rate curves for the LRU policy with sublinear space. Our algorithm uses O( p^2 * log(n) * log^2(m) / epsilon^2 ) bits of space and approximates the hit rate curve at p uniformly-spaced points to within additive error epsilon. This is not far from optimal. Any single-pass algorithm with the same guarantees must use Omega(p^2 + epsilon^{-2} + log(n)) bits of space. Furthermore, our use of additive error is necessary. Any single-pass algorithm achieving multiplicative error requires Omega(n) bits of space

The Mediterranean ocean Forecasting System

The Mediterranean Forecasting System (MFS) is operationally working since year 2000 and it is continuously improved in the frame of international projects. The system is part of the Mediterranean Operational Oceanography Network-MOON and MFS is coordinated and operated by the Italian Group of Operational Oceanography (GNOO). The latest upgrades and integration to MFS has been undertaken in the EU-MERSEA and BOSS4GMES Projects. Since October 2005 ten days forecasts are produced daily as well as 15 days of analyses once a week. The daily forecast and weekly analysis data are available in real time to the users through a dedicated ftp service and every day a web bulletin is published on the web site (http://gnoo.bo.ingv.it/mfs). A continuous evaluation in near real time of the forecasts and analyses produced by MFS has been developed in order to continuously verify the system and to provide useful information to the users. The R&D is focused on different aspects of the system. A new basin scale ocean model nested with operational MERCATOR global model has been developed and run in real time operationally for a test period together with a new assimilation scheme based on the 3DVAR. This system is now under evaluation. Important activities have been carried out to: implement and test a Bayesian methodologies of Ensemble and Super-Ensemble for the Mediterranean sea; produce 20 years of re-analysis; re-formulate the air-sea fluxes bulk formulae; develop dedicated products to support particular request of end users such as: indicators, real time oil spill forecasting, search & rescue

Estrategias de manejo químico de la rabia del garbanzo (Ascochyta rabiei)

El manejo químico es una de las principales estrategias para el manejo de la rabia del garbanzo, causada por el hongo Ascochyta rabiei, la enfermedad más agresiva del cultivo del garbanzo (Cicer arietinum L.) a nivel mundial. Se evaluó la capacidad de control de 20 fungicidasaplicados en dos momentos de intervención: i) preventiva (con valores de incidencia menores al 1%), aplicando los fungicidas y repitiendo los mismos a los a los 21 días; y ii) curativa (realizando aplicaciones simples al registrar 100% de incidencia). Se aplicó con mochila experimental, en diseño completamente aleatorizado, de micro parcelas con cuatro repeticiones. Se evalúo: i) incidencia, ii) severidad (como porcentaje visual de área de la planta afectada), iii) control (%), iv) rendimiento (kg/ha) y v) calibre. Los resultados fueron analizados a través de análisis de la varianza y test de comparación de medias. Todos los fungicidas probados presentaron control sobre rabia. Las diferencias tanto en incidencia como en severidad fueron estadísticamente significativas. Los tratamientos preventivos superaron el 85% de control en todos los casos, los tratamientoscurativos lograron un control promedio del 67%. Todos los tratamientos presentaron respuestas positivas en rendimiento y diferencias estadísticamente significativas, las mismas fueron desde los 274,2 kg/ha a 1552,7 kg/ha. Los tratamientos más sanos presentaronmayores porcentajes de calibres mayores (9 y 8) y menor cantidad de clasificación bajo zaranda, todos los tratamientos se diferenciaron estadísticamente. Se logró generar información del accionar de diferentes fungicidas frente a rabia del garbanzo, así como de su respuesta en rendimiento y calidad de grano

Testicular tuberculosis presenting with metastatic intracranial tuberculomas only: a case report

<p>Abstract</p> <p>Introduction</p> <p>Intracranial tuberculomas are a rare complication of tuberculosis occurring through hematogenous spread from an extracranial source, most often of pulmonary origin. Testicular tuberculosis with only intracranial spread is an even rarer finding and to the best of our knowledge, has not been reported in the literature. Clinical suspicion or recognition and prompt diagnosis are important because early treatment can prevent patient deterioration and lead to clinical improvement.</p> <p>Case presentation</p> <p>We present the case of a 51-year-old African man with testicular tuberculosis and multiple intracranial tuberculomas who was initially managed for testicular cancer with intracranial metastasis. He had undergone left radical orchidectomy, but subsequently developed hemiparesis and lost consciousness. Following histopathological confirmation of the postoperative sample as chronic granulomatous infection due to tuberculosis, he sustained significant clinical improvement with antituberculous therapy, recovered fully and was discharged at two weeks post-treatment.</p> <p>Conclusion</p> <p>The clinical presentation of intracranial tuberculomas from an extracranial source is protean, and delayed diagnosis could have devastating consequences. The need to have a high index of suspicion is important, since neuroimaging features may not be pathognomonic.</p

Radiologist experience and CT examination quality determine metastasis detection in patients with esophageal or gastric cardia cancer

We aimed to separate the influence of radiologist experience from that of CT quality in the evaluation of CT examinations of patients with esophageal or gastric cardia cancer. Two radiologists from referral centers ('expert radiologists') and six radiologists from regional non-referral centers ('non-expert radiologists') performed 240 evaluations of 72 CT examinations of patients diagnosed with esophageal or gastric cardia cancer between 1994 and 2003. We used conditional logistic regression analysis to calculate odds ratios (OR) for the likelihood of a correct diagnosis. Expert radiologists made a correct diagnosis of the presence or absence of distant metastases according to the gold standard almost three times more frequently (OR 2.

Challenges for Sustained Observing and Forecasting Systems in the Mediterranean Sea

The Mediterranean community represented in this paper is the result of more than 30 years of EU and nationally funded coordination, which has led to key contributions in science concepts and operational initiatives. Together with the establishment of operational services, the community has coordinated with universities, research centers, research infrastructures and private companies to implement advanced multi-platform and integrated observing and forecasting systems that facilitate the advancement of operational services, scientific achievements and mission-oriented innovation. Thus, the community can respond to societal challenges and stakeholders needs, developing a variety of fit-for-purpose services such as the Copernicus Marine Service. The combination of state-of-the-art observations and forecasting provides new opportunities for downstream services in response to the needs of the heavily populated Mediterranean coastal areas and to climate change. The challenge over the next decade is to sustain ocean observations within the research community, to monitor the variability at small scales, e.g., the mesoscale/submesoscale, to resolve the sub-basin/seasonal and inter-annual variability in the circulation, and thus establish the decadal variability, understand and correct the model-associated biases and to enhance model-data integration and ensemble forecasting for uncertainty estimation. Better knowledge and understanding of the level of Mediterranean variability will enable a subsequent evaluation of the impacts and mitigation of the effect of human activities and climate change on the biodiversity and the ecosystem, which will support environmental assessments and decisions. Further challenges include extending the science-based added-value products into societal relevant downstream services and engaging with communities to build initiatives that will contribute to the 2030 Agenda and more specifically to SDG14 and the UN's Decade of Ocean Science for sustainable development, by this contributing to bridge the science-policy gap. The Mediterranean observing and forecasting capacity was built on the basis of community best practices in monitoring and modeling, and can serve as a basis for the development of an integrated global ocean observing system

Challenges for Sustained Observing and Forecasting Systems in the Mediterranean Sea

The Mediterranean community represented in this paper is the result of more than 30 years of EU and nationally funded coordination, which has led to key contributions in science concepts and operational initiatives. Together with the establishment of operational services, the community has coordinated with universities, research centers, research infrastructures and private companies to implement advanced multi-platform and integrated observing and forecasting systems that facilitate the advancement of operational services, scientific achievements and mission-oriented innovation. Thus, the community can respond to societal challenges and stakeholders needs, developing a variety of fit-for-purpose services such as the Copernicus Marine Service. The combination of state-of-the-art observations and forecasting provides new opportunities for downstream services in response to the needs of the heavily populated Mediterranean coastal areas and to climate change. The challenge over the next decade is to sustain ocean observations within the research community, to monitor the variability at small scales, e.g., the mesoscale/submesoscale, to resolve the sub-basin/seasonal and inter-annual variability in the circulation, and thus establish the decadal variability, understand and correct the model-associated biases and to enhance model-data integration and ensemble forecasting for uncertainty estimation. Better knowledge and understanding of the level of Mediterranean variability will enable a subsequent evaluation of the impacts and mitigation of the effect of human activities and climate change on the biodiversity and the ecosystem, which will support environmental assessments and decisions. Further challenges include extending the science-based added-value products into societal relevant downstream services and engaging with communities to build initiatives that will contribute to the 2030 Agenda and more specifically to SDG14 and the UN's Decade of Ocean Science for sustainable development, by this contributing to bridge the science-policy gap. The Mediterranean observing and forecasting capacity was built on the basis of community best practices in monitoring and modeling, and can serve as a basis for the development of an integrated global ocean observing system