Low delay video coding

Analogue wireless cameras have been employed for decades, however they have not become an universal solution due to their difficulties of set up and use. The main problem is the link robustness which mainly depends on the requirement of a line-of-sight view between transmitter and receiver, a working condition not always possible. Despite the use of tracking antenna system such as the Portable Intelligent Tracking Antenna (PITA [1]), if strong multipath fading occurs (e.g. obstacles between transmitter and receiver) the picture rapidly falls apart. Digital wireless cameras based on Orthogonal Frequency Division Multiplexing (OFDM) modulation schemes give a valid solution for the above problem. OFDM offers strong multipath protection due to the insertion of the guard interval; in particular, the OFDM-based DVB-T standard has proven to offer excellent performance for the broadcasting of multimedia streams with bit rates over 10 Mbps in difficult terrestrial propagation channels, for fixed and portable applications. However, in typical conditions, the latency needed to compress/decompress a digital video signal at Standard Definition (SD) resolution is of the order of 15 frames, which corresponds to ≃ 0.5 sec. This delay introduces a serious problem when wireless and wired cameras have to be interfaced. Cabled cameras do not use compression, because the cable which directly links transmitter and receiver does not impose restrictive bandwidth constraints. Therefore, the only latency that affects a cable cameras link system is the on cable propagation delay, almost not significant, when switching between wired and wireless cameras, the residual latency makes it impossible to achieve the audio-video synchronization, with consequent disagreeable effects. A way to solve this problem is to provide a low delay digital processing scheme based on a video coding algorithm which avoids massive intermediate data storage. The analysis of the last MPEG based coding standards puts in evidence a series of problems which limits the real performance of a low delay MPEG coding system. The first effort of this work is to study the MPEG standard to understand its limit from both the coding delay and implementation complexity points of views. This thesis also investigates an alternative solution based on HERMES codec, a proprietary algorithm which is described implemented and evaluated. HERMES achieves better results than MPEG in terms of latency and implementation complexity, at the price of higher compression ratios, which means high output bit rates. The use of HERMES codec together with an enhanced OFDM system [2] leads to a competitive solution for wireless digital professional video applications

Population structure and genetic diversity of the threatened quillwort Iso\uebtes malinverniana and implication for conservation

62010 GENR 1reservedInternationalItalian coauthor/editorThe goal of this research was to investigate genetic variation inIsoëtes malinverniana(Isoëtaceae) to select candidate populations for future conservation efforts. To this aim, ISSR and AFLP analyses, carried out using six and four primer combinations, respectively, produced a total of 425 bands, 97.18% of which were polymorphic. Our results suggest thatI. malinverniana shows medium to high genetic diversity (mean Nei’s genetic diversity: H= 0.1491 for ISSR data; H= 0.2289 for AFLP data) and a substantial amount of gene flow between the analysed populations (Nm = 1.768, with combined ISSR and AFLP data). Themoderate levels of population differentiation support the hypothesis that the fragmentation and isolation ofI. malinverniana occurred only recently, probably due to the intensive agriculture practice and water pollution. These results will be used to focus further studies aimed at supporting reintroduction programs within suitable sites of the distribution area.restrictedGentili, R.; Abeli, T.; Rossi, G.; Li, M.; Varotto, C.; Sgorbati, S.Gentili, R.; Abeli, T.; Rossi, G.; Li, M.; Varotto, C.; Sgorbati, S

A Pipeline of Associative Memory Boards for Track Finding

We present a pipeline of associative memory boards for track finding, which satisfies the requirements of level two triggers of the next large hadron collider experiments. With respect to previous realizations, the pipelined architecture warrants full scalability of the memory bank, increased bandwidth (by one order of magnitude), and increased number of detector layers (by a factor of two). Each associative memory board consists of four smaller boards, each containing 32 programmable associative memory chips, implemented with a low-cost commercial field-programmable gate array (FPGA). FPGA programming has been optimized for maximum efficiency in terms of pattern density, while printed circuitboard design has been optimized in terms of modularity and FPGA chip density. A complete associative memory board has been successfully tested at 40 MHz; it can contain 7.2 10 3 particle trajectories

Nitric oxide and frataxin: two players contributing to maintain cellular iron homeostasis

BackgroundNitric oxide (NO) is a signalling and physiologically active molecule in animals, plants and bacteria. The specificity of the molecular mechanism(s) involved in transducing the NO signal within and between cells and tissues is still poorly understood. NO has been shown to be an emerging and potent signal molecule in plant growth, development and stress physiology. The NO donor S-nitrosoglutathion (GSNO) was shown to be a biologically active compound in plants and a candidate for NO storage and/or mobilization between plant tissues and cells. NO has been implicated as a central component in maintaining iron bioavailavility in plants. Scope and ConclusionsIron is an essential nutrient for almost all organisms. This review presents an overview of the functions of NO in iron metabolism in animals and discusses how NO production constitutes a key response in plant iron sensing and availability. In plants, NO drives downstream responses to both iron deficiency and iron overload. NO-mediated improvement of iron nutrition in plants growing under iron-deficient conditions represents a powerful tool to cope with soils displaying low iron availability. An interconversion between different redox forms based on the iron and NO status of the plant cells might be the core of a metabolic process driving plant iron homeostasis. Frataxin, a recently identified protein in plants, plays an important role in mitochondria biogenesis and in maintaining mitochondrial iron homeostasis. Evidence regarding the interaction between frataxin, NO and iron from analysis of frataxin knock-down Arabidopsis thaliana mutants is reviewed and discussed.Fil: Ramírez, Leonor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Zabaleta, Eduardo Julian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; ArgentinaFil: Lamattina, Lorenzo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Biológicas. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentin