Beyond the target area: an integrative view of tDCS-induced motor cortex modulation in patients and athletes

Transcranial Direct Current Stimulation (tDCS) is a non-invasive technique used to modulate neural tissue. Neuromodulation apparently improves cognitive functions in several neurologic diseases treatment and sports performance. In this study, we present a comprehensive, integrative review of tDCS for motor rehabilitation and motor learning in healthy individuals, athletes and multiple neurologic and neuropsychiatric conditions. We also report on neuromodulation mechanisms, main applications, current knowledge including areas such as language, embodied cognition, functional and social aspects, and future directions. We present the use and perspectives of new developments in tDCS technology, namely high-definition tDCS (HD-tDCS) which promises to overcome one of the main tDCS limitation (i.e., low focality) and its application for neurological disease, pain relief, and motor learning/rehabilitation. Finally, we provided information regarding the Transcutaneous Spinal Direct Current Stimulation (tsDCS) in clinical applications, Cerebellar tDCS (ctDCS) and its influence on motor learning, and TMS combined with electroencephalography (EEG) as a tool to evaluate tDCS effects on brain function

An Analysis of Errors in Graph-Based Keypoint Matching and Proposed Solutions

International audienceAn error occurs in graph-based keypoint matching when key-points in two different images are matched by an algorithm but do not correspond to the same physical point. Most previous methods acquire keypoints in a black-box manner, and focus on developing better algorithms to match the provided points. However to study the complete performance of a matching system one has to study errors through the whole matching pipeline, from keypoint detection, candidate selection to graph optimisation. We show that in the full pipeline there are six different types of errors that cause mismatches. We then present a matching framework designed to reduce these errors. We achieve this by adapting keypoint detectors to better suit the needs of graph-based matching, and achieve better graph constraints by exploiting more information from their keypoints. Our framework is applicable in general images and can handle clutter and motion discontinuities. We also propose a method to identify many mismatches a posteriori based on Left-Right Consistency inspired by stereo matching due to the asymmetric way we detect keypoints and define the graph

A Model for the Development of the Rhizobial and Arbuscular Mycorrhizal Symbioses in Legumes and Its Use to Understand the Roles of Ethylene in the Establishment of these two Symbioses

We propose a model depicting the development of nodulation and arbuscular mycorrhizae. Both processes are dissected into many steps, using Pisum sativum L. nodulation mutants as a guideline. For nodulation, we distinguish two main developmental programs, one epidermal and one cortical. Whereas Nod factors alone affect the cortical program, bacteria are required to trigger the epidermal events. We propose that the two programs of the rhizobial symbiosis evolved separately and that, over time, they came to function together. The distinction between these two programs does not exist for arbuscular mycorrhizae development despite events occurring in both root tissues. Mutations that affect both symbioses are restricted to the epidermal program. We propose here sites of action and potential roles for ethylene during the formation of the two symbioses with a specific hypothesis for nodule organogenesis. Assuming the epidermis does not make ethylene, the microsymbionts probably first encounter a regulatory level of ethylene at the epidermis–outermost cortical cell layer interface. Depending on the hormone concentrations there, infection will either progress or be blocked. In the former case, ethylene affects the cortex cytoskeleton, allowing reorganization that facilitates infection; in the latter case, ethylene acts on several enzymes that interfere with infection thread growth, causing it to abort. Throughout this review, the difficulty of generalizing the roles of ethylene is emphasized and numerous examples are given to demonstrate the diversity that exists in plants

Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950–2019: a comprehensive demographic analysis for the Global Burden of Disease Study 2019

Background: Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. Methods: 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10–14 and 50–54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed age-specific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. Findings: The global TFR decreased from 2•72 (95% uncertainty interval [UI] 2•66–2•79) in 2000 to 2•31 (2•17–2•46) in 2019. Global annual livebirths increased from 134•5 million (131•5–137•8) in 2000 to a peak of 139•6 million (133•0–146•9) in 2016. Global livebirths then declined to 135•3 million (127•2–144•1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2•1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27•1% (95% UI 26•4–27•8) of global livebirths. Global life expectancy at birth increased from 67•2 years (95% UI 66•8–67•6) in 2000 to 73•5 years (72•8–74•3) in 2019. The total number of deaths increased from 50•7 million (49•5–51•9) in 2000 to 56•5 million (53•7–59•2) in 2019. Under-5 deaths declined from 9•6 million (9•1–10•3) in 2000 to 5•0 million (4•3–6•0) in 2019. Global population increased by 25•7%, from 6•2 billion (6•0–6•3) in 2000 to 7•7 billion (7•5–8•0) in 2019. In 2019, 34 countries had negative natural rates of increase; in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58•6 years (56•1–60•8) in 2000 to 63•5 years (60•8–66•1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019. Interpretation: Over the past 20 years, fertility rates have been dropping steadily and life expectancy has been increasing, with few exceptions. Much of this change follows historical patterns linking social and economic determinants, such as those captured by the GBD Socio-demographic Index, with demographic outcomes. More recently, several countries have experienced a combination of low fertility and stagnating improvement in mortality rates, pushing more populations into the late stages of the demographic transition. Tracking demographic change and the emergence of new patterns will be essential for global health monitoring. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

Global burden of 87 risk factors in 204 countries and territories, 1990�2019: a systematic analysis for the Global Burden of Disease Study 2019

Background: Rigorous analysis of levels and trends in exposure to leading risk factors and quantification of their effect on human health are important to identify where public health is making progress and in which cases current efforts are inadequate. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a standardised and comprehensive assessment of the magnitude of risk factor exposure, relative risk, and attributable burden of disease. Methods: GBD 2019 estimated attributable mortality, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs) for 87 risk factors and combinations of risk factors, at the global level, regionally, and for 204 countries and territories. GBD uses a hierarchical list of risk factors so that specific risk factors (eg, sodium intake), and related aggregates (eg, diet quality), are both evaluated. This method has six analytical steps. (1) We included 560 risk�outcome pairs that met criteria for convincing or probable evidence on the basis of research studies. 12 risk�outcome pairs included in GBD 2017 no longer met inclusion criteria and 47 risk�outcome pairs for risks already included in GBD 2017 were added based on new evidence. (2) Relative risks were estimated as a function of exposure based on published systematic reviews, 81 systematic reviews done for GBD 2019, and meta-regression. (3) Levels of exposure in each age-sex-location-year included in the study were estimated based on all available data sources using spatiotemporal Gaussian process regression, DisMod-MR 2.1, a Bayesian meta-regression method, or alternative methods. (4) We determined, from published trials or cohort studies, the level of exposure associated with minimum risk, called the theoretical minimum risk exposure level. (5) Attributable deaths, YLLs, YLDs, and DALYs were computed by multiplying population attributable fractions (PAFs) by the relevant outcome quantity for each age-sex-location-year. (6) PAFs and attributable burden for combinations of risk factors were estimated taking into account mediation of different risk factors through other risk factors. Across all six analytical steps, 30 652 distinct data sources were used in the analysis. Uncertainty in each step of the analysis was propagated into the final estimates of attributable burden. Exposure levels for dichotomous, polytomous, and continuous risk factors were summarised with use of the summary exposure value to facilitate comparisons over time, across location, and across risks. Because the entire time series from 1990 to 2019 has been re-estimated with use of consistent data and methods, these results supersede previously published GBD estimates of attributable burden. Findings: The largest declines in risk exposure from 2010 to 2019 were among a set of risks that are strongly linked to social and economic development, including household air pollution; unsafe water, sanitation, and handwashing; and child growth failure. Global declines also occurred for tobacco smoking and lead exposure. The largest increases in risk exposure were for ambient particulate matter pollution, drug use, high fasting plasma glucose, and high body-mass index. In 2019, the leading Level 2 risk factor globally for attributable deaths was high systolic blood pressure, which accounted for 10·8 million (95 uncertainty interval UI 9·51�12·1) deaths (19·2% 16·9�21·3 of all deaths in 2019), followed by tobacco (smoked, second-hand, and chewing), which accounted for 8·71 million (8·12�9·31) deaths (15·4% 14·6�16·2 of all deaths in 2019). The leading Level 2 risk factor for attributable DALYs globally in 2019 was child and maternal malnutrition, which largely affects health in the youngest age groups and accounted for 295 million (253�350) DALYs (11·6% 10·3�13·1 of all global DALYs that year). The risk factor burden varied considerably in 2019 between age groups and locations. Among children aged 0�9 years, the three leading detailed risk factors for attributable DALYs were all related to malnutrition. Iron deficiency was the leading risk factor for those aged 10�24 years, alcohol use for those aged 25�49 years, and high systolic blood pressure for those aged 50�74 years and 75 years and older. Interpretation: Overall, the record for reducing exposure to harmful risks over the past three decades is poor. Success with reducing smoking and lead exposure through regulatory policy might point the way for a stronger role for public policy on other risks in addition to continued efforts to provide information on risk factor harm to the general public. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

Diplospory And Obligate Apomixis In Miconia Albicans (miconieae, Melastomataceae) And An Embryological Comparison With Its Sexual Congener M. Chamissois

Apomixis, or asexual reproduction through seeds, has been reported for species of the tribe Miconieae, Melastomataceae, but details of the process have yet to be described. We analyzed and compared sporogenesis and gametogenesis in the apomictic Miconia albicans and the sexual M. chamissois. The results point to some differences between species, which were related to the apomictic process. In M. albicans microsporogenesis, problems during meiosis and degeneration of its products led to total pollen sterility, while M. chamissois presented normal bicellular pollen grains in the mature anther. The absence or abnormality of meiosis in M. albicans megasporogenesis led to the formation of an unreduced embryo sac and also to egg cell parthenogenesis, which gave rise to the apomictic embryo. Embryo and endosperm development were autonomous, resulting in seeds and fruits independent of pollination and fertilization. Thus, in this species, apomixis can be classified as diplosporic and obligate. In contrast, meiosis was as expected in the sexual M. chamissois, and led to the development of a reduced embryo sac. Despite the divergent pathways, many embryological characteristics were similar between the studied species and other Melastomataceae and they seem to be conservative character states for the family. © 2013 Springer-Verlag Wien.299712531262Allem, A.C., Optimization theory in plant evolution: an overview of long-term evolutionary prospects in the angiosperms (2004) Bot Rev, 69, pp. 225-251Asker, S.E., Progress in apomixis research (1979) Hereditas, 91, pp. 231-240Asker, S.E., Jerling, L., (1992) Apomixis in Plants, , Boca Raton: CRC PressBaumgratz, J.F.A., Souza, M.L.D.R., Woodgyer, E.M., NicLughada, E.M., Polysporangiate anthers: described for the first time in Melastomataceae (1996) Kew Bull, 51, pp. 133-144Baumgratz, J.F.A., Bernardo, K.F.R., Chiavegatto, B., Goldenberg, R., Guimarães, P.J.F., Kriebel, R., Martins, A.B., Woodgyer, E., Melastomataceae (2010) Lista de Espécies da Flora do Brasil. Jardim Botânico do Rio de Janeiro, , http://floradobrasil.jbrj.gov.br/2010/FB000161Bicknell, R.A., Koltunow, A.M., Understanding apomixis: recent advances and remaining conundrums (2004) Plant Cell, 16, pp. 229-245Borges, H.B.N., (1991) Biologia reprodutiva de quatro espécies de Melastomataceae., , Dissertation, Universidade Estadual de CampinasCaetano, A.P.S., (2010) Apomixia e reprodução sexuada em espécies de Miconia Ruiz & Pavón, Melastomataceae., , Dissertation, Universidade Estadual de CampinasCaetano, A.P.S., Teixeira, S.P., Forni-Martins, E.R., Carmello-Guerreiro, S.M., Pollen insights into apomictic and sexual Miconia (Miconieae, Melastomataceae) (2013) Int J Plant Sci, 174 (5)Carman, J.G., Asynchronous expression of duplicate genes in angiosperm may cause apomixis, bispory, tetraspory, and polyembryony (1997) Biol J Linn Soc, 61, pp. 51-94Clausing, G., Renner, S.S., Molecular phylogenetics of Melastomataceae and Memecylaceae: implications for character evolution (2001) Am J Bot, 88, pp. 486-498Cooper, D.C., Brink, R.A., The endosperm-embryo relationship in an autonomous apomict, Taraxacum officinale (1949) Bot Gaz, 111, pp. 139-153Cortez, P.A., Carmello-Guerreiro, S.M., Ontogeny and structure of the pericarp and the seed coat of Miconia albicans (Sw.) Triana (Melastomataceae) from "cerrado", Brazil (2008) Rev Bras Bot, 31, pp. 71-79Cortez, P.A., Carmello-Guerreiro, S.M., Teixeira, S.P., Understanding male sterility in Miconia species (Melastomataceae)-a morphological approach (2012) Aust J Bot, 60, pp. 506-516Davis, G.L., (1966) Systematic Embryology of the Angiosperms, , New York: John Wileyden Nijs, H.C.M., Menken, S.B.J., Relations between breeding system, ploidy level, and taxonomy in some advanced sections of Taraxacum (1996) Advances in Compositae Systematics, pp. 665-677. , H. D. N. Hind and H. J. 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Performance Comparison Of Convolutional And Turbo Convolutional Codes For Isdb-t In Awgn And Brazilian Channels

This work intends to demonstrate the improvements applied in the Integrated System Digital Broadcasting-Terrestrial (ISDB-T). The turbo processing has been considered one of the most promising techniques for the improvement of performance in communication systems. The use of turbo convolutional codes (TCCs) combined with soft decision demapping is proposed for reduction of signal to noise rate (SNR) threshold at reception. Some simulations are done using AWGN and typical multipath brazilian channels. Therefore, it is concluded that the proposed Turbo ISDB-T performance is better than the conventional ISDB-T in those cases. © 2006 IEEE.361366(1998) Specification of Channel Coding, Framing Structure and Modulation, , Terrestrial Integrated Services Digital Broadcasting (ISDB-T) DocumentSET/ABERT Digital Television Systems - Brazilian tests - Final Report, ANATEL SP March 2000Berrou, C., Glavieux, A., Thitimajshima, P., Near Shannon Limit Error-Correcting Coding and Decoding Turbo Codes (1993) Proc. Int. Conf. Communications, pp. 1064-1070. , MayTüchler, M., Koetter, R., Singer, A.C., Turbo Equalization: Principles and New Results (2002) IEEE Transactions on Communications, 50 (5). , MaySantos, A., Guimarães, D., A Block Turbo Equalizer Scheme (2005) XXII Simpósio Brasileiro de Telecomunicaçõ es SBrT, , SeptYubing, Z., Jingming, K., Jiakang, L., Turbo ESAE channel estimation on OFDM systems (2004) 7 th International Conference on Signal Processing ICSP04, 2, pp. 1653-1656. , SeptZhijun, F., Shenghua, X., Changxuan, W., Shiqian, W., Zhengyou, W., Weiming, Z., Joint source-channel coding for MPEG-4 streams transmission over 3G networks (2005) IEEE International Conference on Wireless Communications, Networking and Mobile Computing, 2, pp. 23-26,1261-1264. , SeptHagenauer, J., Gortz, N., The turbo principle in joint source-channel coding (2003) Information Theory Workshop, pp. 275-278. , 31 March-4 AprilQiao, X., Cai, Y., Xu, Y., Joint iterative decision feedback channel estimation for turbo coded V-BLAST MIMO-OFDM systems (2005) IEEE International Symposium on Communication and Information Technology ISCIT, 2, pp. 1384-1388. , 12-14OctNavarro, M., Grant, A., Joint channel estimation and decoding for space-time turbo codes (2002) IEEE International Symposium on Information Theory, p. 161European Telecommunications Standards Institute ETSI, EN 301 958 DVB-RCT standard, 2003Barratt, K.A., Coulton, P., Honary, B., Defining performance limits for turbo-code assisted synchronization in DVB-S systems (2001) Transaction on Broadcasting, 47, pp. 348-356. , Dec, pagesPyndiah, R.M., Near-optimum decoding of product codes: Block turbo codes (1998) IEEE Trans. Commun, 46, pp. 1003-1010. , AugNickl, H., Hagenauer, J., Burkert, F., Approaching Shannon's Capacity Limit by 0.2 dB Using Simple Hamming Codes (1997) IEEE Communication Letters, 15, pp. 130-132. , SeptemberChen, Y., Parhi, K.K., Parallel decoding of interleaved single parity check turbo product codes, Signal Processing Systems, 2002. (SIPS '02) (2002) IEEE Workshop on, 16-18, pp. 27-32. , OctGuimarães, D.A., Portugueis, J., A Class of Product Codes and Its Interative (Turbo) decoding (2003) Proceding of the 3 rd International Symposium on Turbo Codes &ampRelated Topics, pp. 431-434. , Brest, France, Sep. 1-5Cuevas, J., Adde, P., Kerouedan, S., Pyndiah, R., New architecture for high data rate turbo decoding of product codes (2002) Global Telecommunications Conference, GLOBECOM '02, 2, pp. 1363-1367. , IEEE, 17-21 NovArgon, C., McLaughlin, S.W., Efficient decoding of turbo product codes (2001) Proc. 39th Annual Allerton Conference on Communications, Control, and Computing, , Monticello, IL, OctMoon, J., Li, Y., On reduced-complexity soft demapping in MIMO systems with spatial multiplexing (2005) IEEE International Conference on Communications ICC, 4, pp. 2302-2307. , 16-20 MayHokfelt, J., Edfors, O., Maseng, T., Interleaver design for turbo codes based on the performance of iterative decoding (1999) IEEE International Conference on Communications, 1, pp. 93-97. , 6-10 Jun

Improving Dvb-t For Brazilian Environments

In this paper the improvement in the performance obtained by a Time Interleaving applied to DVB-T scheme are analyzed in impulsive noise environments. The performance is evaluated in terms of bit error rate probability for 0ms, 100ms and 200ms of time interleaving length. The results are compared with the standard DVB-T (Digital Video Broadcasting - Terrestrial) evaluated on Impulsive Noise channel and Multipath combined with impulsive noise channel. Simulation results shows that employing Time Interleaving only with 100ms the overall system performance can improve significantly. These results are obtained applying an appropriate interleaving after the Mapper of DVB-T system. © 2006 IEEE.376380ANATEL SP, www.anatel.gov.br (2000) Digital Television Systems - Brazilian testes - Final Report, , SET/ABERT Part 1, MarchANATEL SP, www.anatel.gov.br (2000) Digital Television Systems - Brazilian testes - Final Report, , SET/ABERT Part 2, MayNikookar, H., Nathoeni, D., Performance evaluation of OFDM transmission over impulsive noisy channels (2002) 13 th IEEE International Symposium on Personal, Indoor and Mobile Radio Communication, 15-18, 2, pp. 550-554. , Pages, SeptHazmi, A., Rinne, J., Kuusisto, T., Renfors, M., Performance evaluation of symbol synchronization in OFDM systems over impulsive noisy channels (2004) Vehicular Technology Conference, , SpringHazmi, A., Rinne, J., Kuusisto, T., Renfors, M., An enhanced impulsive burst cancellation method using pilots and soft bits in OFDM based systems (2004) IEEE 5 th Worshop on Signal Processing Advances in Wireless Communications, pp. 373-376. , Pages, 11-14 JulyZhidkov, S.V., Impulsive noise suppression in OFDM-based communication systems (2003) IEEE Transaction on Consumer Electronics, 49 (4), pp. 944-948. , Pages, NovZhidkov, S.V., (2006) Performance analysis and optimization of OFDM receiver with blanking nonlinearity in impulsive noise environment, 55 (1), pp. 234-242. , Jan, PagesAbdelkefi, F., Duhamel, P., Alberge, F., Impulsive noise cancellation in multicarrier transmission (2005) IEEE Transaction on Communication, 53 (1), pp. 94-106. , Pages, JanAndrews, K.S.W., Heegard, C., Kozen, D., A theory of interleavers, Techical Report, , TR97-1634, Departmnet of Computer Science, June 1997Channel coding, frame structure and modulation scheme for terrestrial integrate service digital broadcasting (ISDB-T) (1999), ITU-R WP 11A/59, ITU-R WP 11A/59-E, May 17Dolinar, S., Divsalar, D., Pollara, F., Code performance as a function of block size TMO Progress Report, , 42-133, JPL, May 1998Digital Video Broadcasting (DVB) (1997) Framing structure, channel coding and modulation for digital Terrestrial television (DVB-T), , ETSI European Telecommunications Standards Institute, MarchG. Bedicks, C. E. Dantas, F. Sukys, F. Yamada, L. T. M. Raunheitte, C. Akamine, Digital Signal Disturbed by Impulsive Noise 53th Annual IEEE Broadcast Symposium, Washington D.C. USA, 2003Lago-Fernández, J., Salter, J., Modelling impulsive interference in DVB-T - Statistical analysis, test waveforms and receiver performance (2004) BBC EBU Technical Review, , Jul

Finding Correspondence from Multiple Images via Sparse and Low-Rank Decomposition

Abstract. We investigate the problem of finding the correspondence from multiple images, which is a challenging combinatorial problem. In this work, we propose a robust solution by exploiting the priors that the rank of the ordered patterns from a set of linearly correlated images should be lower than that of the disordered patterns, and the errors among the reordered patterns are sparse. This problem is equivalent to find a set of optimal partial permutation matrices for the disordered patterns such that the rearranged patterns can be factorized as a sum of a low rank matrix and a sparse error matrix. A scalable algorithm is proposed to approximate the solution by solving two sub-problems sequentially: minimization of the sum of nuclear norm and l1 norm for solving relaxed partial permutation matrices, followed by a binary integer programming to project each relaxed partial permutation matrix to the feasible solution. We verify the efficacy and robustness of the proposed method with extensive experiments with both images and videos