Amyotrophic lateral sclerosis is characterized by a progressive degeneration of the corticospinal tract motor neurons. Growing evidence suggests that degeneration may begin at the distal axon proceeding in a dying-back pattern. It seemed therefore of interest to investigate synaptic transmission at the neuromuscular junction (NMJ) in pre- and symptomatic phases of the disease. Endplate potentials (EPPs), miniatures endplate potentials (MEPPs) and giant MEPPs (GMEPPs) were recorded from innervated diaphragm muscle fibers from 4–6 and 12-15 weeks-old SOD1(G93A) mice and non-transgenic aged-matched littermates (WT). In the pre-symptomatic phase, SOD1(G93A) mice exhibited a significant increase in the mean amplitude of EPPs together with an increase in the mean quantal content of EPPs, suggesting that more acetylcholine is being released into the synaptic cleft. SOD1(G93A) mice presented a higher frequency of GMEPPs, suggestive of intracellular Ca2+ deregulation in nerve terminals. The increase in the mean amplitude of MEPPs and the decreased mean rise-time of MEPPs in SOD1(G93A) mice point to post-synaptic related changes. In the symptomatic phase, electrophysiological data showed evidence for two NMJ groups in SOD1(G93A) mice: SOD1a and SOD1b. SOD1a group presented reduced mean amplitude of both EPPs and MEPPs. The mean rise-time of MEPPs was increased, when compared to WT and to SOD1b group, indicating impairments in the neuromuscular transmission. In contrast, the neuromuscular transmission of SOD1b group was not different from age-matched WT nor pre-symptomatic SOD1(G93A) mice, being somehow in between both groups. Altogether these results show that the neuromuscular transmission of SOD1(G93A) mice is enhanced in the pre-symptomatic phase. In the symptomatic phase our results are consistent with the hypothesis that the diaphragm of SOD1(G93A) mice is undergoing cycles of denervation/re-innervation supported by mixed neuromuscular junction populations. These early changes in the neuromuscular transmission of SOD1(G93A) mice suggest that the ALS associated events start long before symptoms onset.

The integration of the link-level and network-level simulators described in this paper give accurate and realistic results that can next be used in more studies that focus on network layer aspects of packet based services over HSDPA.

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1. The red-swamp crayfish (Procambarus clarkii) is an invasive species and an important pest of wet-seeded rice fields (Oryza sativa) in California (U.S.A.) and in Portugal. Our work quantifies rice consumption and non-consumptive destruction and identifies the types of direct damage inflicted by crayfish. 2. The following fractions were quantified in the presence and absence of crayfish and at 3 and 6 days of rice development: (1) non-germinated seeds, (2) damaged seeds, (3) seeds not recovered, (4) intact rooted seedlings, (5) rooted damaged seedlings, (6) uprooted intact seedlings, (7) uprooted damaged seedlings. 3. Coarse particulate organic matter (CPOM) fragments produced during the feeding process were <2% of the material removed by crayfish. 4. Damage occurred with or without uprooting of the plants, but the incidence of uprooting without consumption was low (1.4%). 5. Consumption of recently developed parts of the rice plant was the main cause of damage and the observed effect was stronger on 6-day-old than on 3-day-old seedlings. Seedlings were more affected by crayfish than were seeds. 6. Crayfish affected the majority of seeds and seedlings available although consumption was low: 0.015 g dry weight (DW) rice g )1 wet weight (WW) crayfish per 12 h at 3 days and 0.063 g DW rice g )1 WW crayfish per 12 h at 6 days. 7. Our results are important for the mitigation of crayfish related problems in rice fields and for understanding the mechanisms of crayfish-macrophyte interactions.

Abstract-The deployment of increasingly dense heterogeneous mobile networks can create high levels of interference among users which, combined with severe time dispersive channels, can result in substantial performance degradation. In order to cope with both effects, in this paper we propose an iterative block decision feedback equalizer (IBDFE) for single carrier (SC) transmissions which makes use of the correlation between the interference in the receiving antennas and minimizes the mean squared error (MSE) of the detected symbols. Our analytic and simulated performance results show that the proposed receiver can clearly outperform the conventional IBDFE and the linear interference rejection combining (IRC) detector in severely time-dispersive channels with strong cochannel interference.

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In this paper, a survey of the mobile data traffic growth over the last decade is performed, showing historically how data consumption patterns have evolved. Based on the results from the survey and the most important factors for unprecedented traffic growth from last years, a set of user-centric services and scenarios are identified as the most prevalent by 2020. Based on service characteristics and subscribers' behaviour and consumption regarding traffic generation, four user segments are derived. All these factors allow introducing an impact model that characterises user segment's behaviour over post-4G cellular networks, namely, its consistency and stability towards traffic generation, data consumption and service usage, providing mobile network operators with relevant information to predict user segment dispersion, stability and risk. Real and estimated market data are used to test the impact model, and most relevant results are shown. Overall, the proposed impact model aims to bring together technological, sociological and also economical perspectives into a single analytical framework, meeting both mobile network operators and subscriber's expectations of high quality of service with continuous cost decrease.

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