Hidden Terminal-Aware Contention Resolution with an Optimal Distribution

Achieving low-power operation in wireless sensor networks with high data load or bursty traffic is challenging. The hidden terminal problem is aggravated with increased amounts of data in which traditional backoff-based contention resolution mechanisms fail or induce high latency and energy costs. We analyze and optimize Strawman, a receiver-initiated contention resolution mechanism that copes with hidden terminals. We propose new techniques to boost the performance of Strawman while keeping the resolution overhead small. We finally validate our improved mechanism via experiments

Rapid Convergecast on Commodity Hardware: Performance Limits and Optimal Policies

ReSensePromo

Near Optimum Power Control and Precoding under Fairness

We consider the problem of setting the uplink signal-to-noise-and-interference (SINR) target and allocating transmit powers for mobile stations in multicell spatial multiplexing wireless systems. Our aim is twofold: to evaluate the potential of such mechanisms in network multiple input multiple output (MIMO) systems, and to develop scalable numerical schemes that allow real-time nearoptimal resource allocation across multiple sites. We formulate two versions of the SINR target and power allocation problem: one for maximizing the sum rate subject to power constraints, and one for minimizing the total power needed to meet a sum-rate target. To evaluate the potential of our approach, we perform a semianalytical study in Mathematica using the augmented Lagrangian penalty function method. We find that the gain of the joint optimum SINR setting and power allocation may be significant depending on the degree of fairness that we impose. We develop a numerical technique, based on successive convexification, for real-time optimization of SINR targets and transmit powers. We benchmark our procedure against the globally optimal solution and demonstrate consistently strong performance in realistic network MIMO scenarios. Finally, we study the impact of near optimal precoding in a multicell MIMO environment and find that precoding helps to reduce the sum transmit power while meeting a capacity target

The MPA mouse breast cancer model: evidence for a role of progesterone receptors in breast cancer

More than 60% of all breast neoplasias are ductal carcinomas expressing estrogen (ER) and progesterone receptors (PR). In contrast, most of the spontaneous, chemically or MMTV induced tumors, as well as tumors arising in genetically modified mice do not express hormone receptors. We developed a model of breast cancer in which the administration of medroxyprogesterone acetate (MPA) to BALB/c female mice induces mammary ductal carcinomas with a mean latency of 52 weeks and an incidence of about 80%. These tumors are hormone-dependent, metastatic, express both ER and PR, and are maintained by syngeneic transplants. The model has been further refined to include mammary carcinomas that evolve through different stages of hormone dependency, as well as several hormone-responsive cell lines. In this review, we describe the main features of this tumor model, highlighting the role of PR as a trigger of key signaling pathways mediating tumor growth. In addition, we discussthe relevance of this model in comparison with other currently used breast cancer models pointing out its advantages and limitations and how, this model may be suitable to unravel key questions in breast cancer.Fil: Lanari, Claudia Lee Malvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Lamb, Caroline Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Fabris, Victoria Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Helguero, Luisa A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Soldati, Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Bottino, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Giulianelli, Sebastian Jesus. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Cerliani, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Wargon, Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Molinolo, Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Public Health Service. National Institute Of Health; Estados Unido

The flare likelihood and region eruption forecasting (FLARECAST) project: flare forecasting in the big data & machine learning era

The European Union funded the FLARECAST project, that ran from January 2015 until February 2018. FLARECAST had a research-to-operations (R2O) focus, and accordingly introduced several innovations into the discipline of solar flare forecasting. FLARECAST innovations were: first, the treatment of hundreds of physical properties viewed as promising flare predictors on equal footing, extending multiple previous works; second, the use of fourteen (14) different machine learning techniques, also on equal footing, to optimize the immense Big Data parameter space created by these many predictors; third, the establishment of a robust, three-pronged communication effort oriented toward policy makers, space-weather stakeholders and the wider public. FLARECAST pledged to make all its data, codes and infrastructure openly available worldwide. The combined use of 170+ properties (a total of 209 predictors are now available) in multiple machine-learning algorithms, some of which were designed exclusively for the project, gave rise to changing sets of best-performing predictors for the forecasting of different flaring levels, at least for major flares. At the same time, FLARECAST reaffirmed the importance of rigorous training and testing practices to avoid overly optimistic pre-operational prediction performance. In addition, the project has (a) tested new and revisited physically intuitive flare predictors and (b) provided meaningful clues toward the transition from flares to eruptive flares, namely, events associated with coronal mass ejections (CMEs). These leads, along with the FLARECAST data, algorithms and infrastructure, could help facilitate integrated space-weather forecasting efforts that take steps to avoid effort duplication. In spite of being one of the most intensive and systematic flare forecasting efforts to-date, FLARECAST has not managed to convincingly lift the barrier of stochasticity in solar flare occurrence and forecasting: solar flare prediction thus remains inherently probabilistic

Sub Programa Cedrella

El Subprograma Cedrela del PROMEF se inició en el año 2010, con el fin de consolidar y dar continuidad al proyecto nacional de Domesticación de especies nativas de alto valor de las Selvas Subtropicales que conducía el INTA desde el año 2006, dirigido a llevar a cultivo especies forestales de alto valor socioeconómico de las Selvas, para incrementar la producción de maderas nobles y recuperar áreas degradadas a fin de mantener la función productiva del bosque y de sus servicios ambientales. El objetivo general del Subprograma Cedrela fue el de proveer a las regiones NOA y NEA de materiales de propagación mejorados de especies nativas emblemáticas ,adaptados a diferentes condiciones ecológicas y finalidades. Las especies más estudiadas hasta el presente son Cedrela angustifolia, C. balansa e y C. fissilis. Sin embargo, la existencia de más de 40 especies maderables/ha promovió la realización de encuestas de opinión para que el sector foresto-industrial definiera las que ingresarían al proceso de domesticación, ya que se requiere de un lapso extendido de tiempo y de un presupuesto considerable para desarrollar los estudios necesarios. En consecuencia, se generaron alianzas estratégicas con Universidades, la Administración de Parques Nacionales (APN), organismos provinciales y empresas. Posteriormente, se fueron incluyendo actividades para Cordia trichotoma y Araucaria angustifolia. El punto de partida fue la caracterización del material genético desde un enfoque poblacional para definir las estrategias de mejora genética y de conservación, dado que se trata mayormente de especies amenazadas. A partir de esta información y con la asistencia de herramientas moleculares se conformaron las poblaciones de mejora, incluyendo materiales con potencial productivo, plasticidad ante el estrés hídrico y térmico y diversidad genética suficiente. Esto permitió la instalación de huertos semilleros clonales y la ubicación de rodales semilleros para afrontar la demanda actual de semillas para los planes de producción sustentable y conservación (ley nacional 26.432 y ley nacional 26.331), así como el establecimiento de ensayos de orígenes y progenies para dar continuidad al programa de mejora, realizar observaciones fenológicas y asegurar la conservación ex situ-in vivo de numerosos genotipos que ya no existen en la naturaleza. Por otro lado, se evaluaron diferentes alternativas de conducción de plantaciones y manejo de vivero para mejorar la sobrevivencia a campo, incluyendo el control de la plaga Hypsipyla grandella. Por último, se realizaron actividades de transferencia de los resultados por diferentes vías de comunicación, poniendo énfasis en el sector productivo ya que reúne a los beneficiarios directos de esta propuesta. Asimismo, se capacitaron recursos humanos para fortalecer los grupos relacionados al uso y conservación de especies forestales nativas.Fil: Fornes, Luis Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Zelener, Noga. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Gauchat, M. Elena. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Inza, M. Virginia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Soldati, María Cristina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; ArgentinaFil: Ruíz, Veronica. No especifíca;Fil: Meloni, Diego Ariel. Universidad Nacional de Santiago del Estero. Facultad de Ciencias Forestales; ArgentinaFil: Grignola, Josefina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Barth, Sara Regina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Ledesma, Tilda. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Salta-jujuy. Estacion Experimental Agropecuaria Yuto.; ArgentinaFil: Tapia, Silvia. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Salta-jujuy. Estacion Experimental Agropecuaria Yuto.; ArgentinaFil: Tarnowski, Christian. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Salta-jujuy. Estacion Experimental Agropecuaria Yuto.; ArgentinaFil: Eskiviski, Edgar Rafael. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Figueredo, Iris. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: González, Paola. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Leiva, Nidia. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Tucuman-Santiago del Estero. Estación Experimental Agropecuaria Famaillá; ArgentinaFil: Rodríguez, Gustavo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Alarcon, Pamela. No especifíca;Fil: Cuello, Roberto. No especifíca;Fil: Gatto, Miguel. No especifíca;Fil: Rotundo, Cristian Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Misiones. Estación Experimental Agropecuaria Montecarlo; ArgentinaFil: Giannoni, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alonso, Fernando M.. No especifíca;Fil: Saravia, Pablo Federico. No especifíca;Fil: Trápani, Adrián Ignacio. No especifíca

European contribution to the study of ROS: A summary of the findings and prospects for the future from the COST action BM1203 (EU-ROS).

The European Cooperation in Science and Technology (COST) provides an ideal framework to establish multi-disciplinary research networks. COST Action BM1203 (EU-ROS) represents a consortium of researchers from different disciplines who are dedicated to providing new insights and tools for better understanding redox biology and medicine and, in the long run, to finding new therapeutic strategies to target dysregulated redox processes in various diseases. This report highlights the major achievements of EU-ROS as well as research updates and new perspectives arising from its members. The EU-ROS consortium comprised more than 140 active members who worked together for four years on the topics briefly described below. The formation of reactive oxygen and nitrogen species (RONS) is an established hallmark of our aerobic environment and metabolism but RONS also act as messengers via redox regulation of essential cellular processes. The fact that many diseases have been found to be associated with oxidative stress established the theory of oxidative stress as a trigger of diseases that can be corrected by antioxidant therapy. However, while experimental studies support this thesis, clinical studies still generate controversial results, due to complex pathophysiology of oxidative stress in humans. For future improvement of antioxidant therapy and better understanding of redox-associated disease progression detailed knowledge on the sources and targets of RONS formation and discrimination of their detrimental or beneficial roles is required. In order to advance this important area of biology and medicine, highly synergistic approaches combining a variety of diverse and contrasting disciplines are needed.The EU-ROS consortium (COST Action BM1203) was supported by the European Cooperation in Science and Technology (COST). The present overview represents the final Action dissemination summarizing the major achievements of COST Action BM1203 (EU-ROS) as well as research news and personal views of its members. Some authors were also supported by COST Actions BM1005 (ENOG) and BM1307 (PROTEOSTASIS), as well as funding from the European Commission FP7 and H2020 programmes, and several national funding agencies

Cross-layer optimization of wireless multi-hop networks

The interest in wireless communications has grown constantly for the past decades, leading to an enormous number of applications and services embraced by billions of users. In order to meet the increasing demand for mobile Internet access, several high data-rate radio networking technologies have been proposed to offer wide area high-speed wireless communications, eventually replacing fixed (wired) networks for many applications. This thesis considers cross-layer optimization of multi-hop radio networks where the system performance can be improved if the traditionally separated network layers are jointly optimized. The networks we consider have links with variable transmission rates, influenced by the allocation of transmission opportunities and channels, modulation and coding schemes and transmit powers. First, we formulate the optimal network operation as the solution to a network utility maximization problem and review decomposition methods from mathematical programming that allow translating a centralized network optimization problem into distributed mechanisms and protocols. Second, particular focus is given to networks employing spatial-reuse TDMA, where we develop detailed distributed solutions for joint end-to-end communication rate selection, multiple time-slot transmission scheduling and power allocation which achieve the optimal network utility. In the process, we introduce a novel decomposition method for convex optimization, establish its convergence and demonstrate how it suggests a distributed solution based on flow control optimization and incremental updates of the transmission schedule. We develop a two-step procedure for distributed maximization of computing the schedule updates (maximizing congestion-weighted throughput) and suggest two schemes for distributed channel reservation and power control under realistic interference models. Third, investigate the advantages of employing multi-user detectors within a CDMA/TDMA framework. We demonstrate how column generation techniques can be combined with resource allocation schemes for the multi-access channel into a very efficient computational method. Fourth, we investigate the benefits and challenges of using the emerging OFDMA modulation scheme within our framework. Specifically, we consider the problem of assigning sub-carriers to wireless links in multi-hop mesh networks. Since the underlying mathematical programming problem is computationally hard, we develop a specialized algorithm that computes optimal near-optimal solutions in a reasonable time and suggest a heuristic for improving computation at the price of relatively modest performance losses.QC 20101117</p

A joint routing-MAC model for cellular-relaying networks

Abstract—We present an iterative joint scheduling-routing algorithm for characterizing the long-term performance of a cellular-relaying network. The physical layer model is based on ideal rate adaptation, fixed transmission power, and average interference. At the MAC layer, time-shares of a common channel are allocated to links in a CSMA/CA-like fashion. At the transport layer, one or more parallel routes can transfer the data flow from a source to the destination, and the average end-user rates are adjusted so as to maximize a global utility function. The general problem of allocating time-shares and selecting link rates is nonconvex. We propose an iterative algorithm and a novel approximation for the physical layer so as to obtain a convex formulation at each iteration step. If only one route is available per source, the problem admits a convex equivalent formulation and the iterative algorithm converges to the global optimum. If more routes per source are available, the problem remains nonconvex. However we show in a simple tractable example that the joint formulation yields sum-log-utility values comparable to the results obtained through exhaustive search of all possible route combinations. I