Frameless ALOHA with Reliability-Latency Guarantees

One of the novelties brought by 5G is that wireless system design has increasingly turned its focus on guaranteeing reliability and latency. This shifts the design objective of random access protocols from throughput optimization towards constraints based on reliability and latency. For this purpose, we use frameless ALOHA, which relies on successive interference cancellation (SIC), and derive its exact finite-length analysis of the statistics of the unresolved users (reliability) as a function of the contention period length (latency). The presented analysis can be used to derive the reliability-latency guarantees. We also optimize the scheme parameters in order to maximize the reliability within a given latency. Our approach represents an important step towards the general area of design and analysis of access protocols with reliability-latency guarantees.Comment: Accepted for presentation at IEEE Globecom 201

On the Derivation of Optimal Partial Successive Interference Cancellation

The necessity of accurate channel estimation for Successive and Parallel Interference Cancellation is well known. Iterative channel estimation and channel decoding (for instance by means of the Expectation-Maximization algorithm) is particularly important for these multiuser detection schemes in the presence of time varying channels, where a high density of pilots is necessary to track the channel. This paper designs a method to analytically derive a weighting factor $\alpha$, necessary to improve the efficiency of interference cancellation in the presence of poor channel estimates. Moreover, this weighting factor effectively mitigates the presence of incorrect decisions at the output of the channel decoder. The analysis provides insight into the properties of such interference cancellation scheme and the proposed approach significantly increases the effectiveness of Successive Interference Cancellation under the presence of channel estimation errors, which leads to gains of up to 3 dB.Comment: IEEE GLOBECOM 201

Detection and Combining Techniques for Asynchronous Random Access with Time Diversity

Asynchronous random access (RA) protocols are particularly attractive for their simplicity and avoidance of tight synchronization requirements. Recent enhancements have shown that the use of successive interference cancellation (SIC) can largely boost the performance of these schemes. A further step forward in the performance can be attained when diversity combining techniques are applied. In order to enable combining, the detection and association of the packets to their transmitters has to be done prior to decoding. We present a solution to this problem, that articulates into two phases. Non-coherent soft-correlation as well as interference-aware soft-correlation are used for packet detection. We evaluate the detection capabilities of both solutions via numerical simulations. We also evaluate numerically the spectral efficiency achieved by the proposed approach, highlighting its benefits.Comment: 6 pages, 7 figures. Work has been submitted to the 11th International ITG Conference on Systems, Communications and Coding 201

From 5G to 6G: Has the Time for Modern Random Access Come?

This short paper proposes the use of modern random access for IoT applications in 6G. A short overview of recent advances in uncoordinated medium access is provided, highlighting the gains that can be achieved by leveraging smart protocol design intertwined with advanced signal processing techniques at the receiver. The authors' vision on the benefits such schemes can yield for beyond-5G systems is presented, with the aim to trigger further discussion.Comment: 2 pages, 1 figure, presented at 6G Summit, Levi, Finland, 201

Trace-metaldynamics in response of increase CO₂ and iron availability in a coastal mesocosm experiment

A mesocosm experiment was performed in the Raunefjord (Norway) to study changes in dissolved Cu (dCu) and Fe (dFe), and in the elemental composition of particles during an Emiliania huxleyi dominated bloom. The CO2 treatments consisted of present (LC; 390 ppmV) and predicted levels (HC; 900 ppmV) and iron conditions were created with the addition of the siderophore desferoxamine B (DFB). Our results showed the DFB addition enhanced the solubility of Fe in this fjord environment. Initially, dFe was comparable among treatments but after the addition, the HC and/or +DFB treatments presented higher levels and finally, the only ones maintaining high dFe were the +DFB treatments. Unlike dCu presented indistinguishable levels in all mesocosms over time. Particulate metals were normalised to P and Al to evaluate the relative influence of biotic and abiotic sources. The Fe:P ratios decreased with time and compared to published phytoplankton ratios suggest Fe storage. On the other hand, Fe:Al ratios were relatively closer to the crustal ratios suggesting that the abiotic source was more important for this metal. Trends for other metals will be discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Differential effects of high-lysine mutations on the accumulation of individual members of a group of proteins encoded by a disperse multigene family in the endosperm of barley (Hordeum vulgare L.)

The CM proteins are a group of major salt-soluble endosperm proteins encoded by a disperse multigene family. The effects of high-lysine mutations on the net accumulation in barley endosperm of three members of this group (CMa, CMb, and CMe) have been investigated. Genes CMa, CMb and CMe are located in chromosomes 1, 4, and 3 respectively. Protein CMe has been found to be identical with a previously described trypsin inhibitor. The three proteins have been quantified in the different genetic stocks by HPLC. The different high-lysine mutations have different effects on the expression patterns of the three genes: CMe is markedly decreased and CMa and CMb are increased in mutant Risø 1508, whereas all three proteins are decreased in Risø 527 and increased in Risø 7 with respect to the wild-type Bomi; CMa and CMb are increased and CMe is unaffected in mutant Risø 56 with respect to the wild-type Carlsberg II; and protein CMe is markedly decreased in Hiproly barley as compared with its sister line CI4362. The implications of these results in connection with the evolution of CM proteins and with the characterization of high-lysine mutations are discusse

The effects of ocean acidification and siderophore additions on trace-metal dynamics during an Emiliania Huxleyi- dominated bloom in a coastal mesocosm experiment

The combined impacts of high CO2 and changes in trace metal availability on plankton remain largely unknown. A 22 days mesocosm experiment was carried out in the Raunefjord, off Bergen, Norway (June 2012) to investigate the interactive effects of increased CO2 and changes in iron availability in the pelagic community. Twelve mesocosms covered by PAR and UVR transparent lids were used. The CO2 treatments consisted of present (LC; 390 ppmV) and predicted levels for year 2100 (HC; 900 ppmV). On day 7, half of the mesocoms were amended with the siderophore desferoxamine B (DFB) at 70 nM (final concentration). We studied changes in dissolved Cu (dCu) and Fe (dFe), and in the elemental composition of particles. Dissolved Fe and dCu were measured by chemiluminescence flow injection analysis, while particulate metals were determined by high-resolution inductively coupled mass spectrometry. The metals were normalised to P and Al to evaluate the relative influence of biotic and abiotic sources. Samples were taken throughout a bloom of the coccolithophore E. huxleyi. Further details will be discussed.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

CM-proteins and thionins in cereals: characterization and cloning of cDNA

The study of cereal albumins and globulins has lagged somewhat behind that of the prolamins, which nave been considered as typical reserve proteins. However, these protein fractions merit closer attention for a variety of reasons. The main individual albumins and globulins are at least as abundant as many prolamin components, and it can be speculated that in a tissue, such as the cereal endosperm, which is completely consumed during germination, al 1 abundant proteins may play a reserve role. They have also a higher proportion of essential amino acids, as compared with the prolamins, and thus may be releyant in connec^ tion with the genetic alteration of overall grain composition. Finally, a high proportion of the main components of these protein fractions have inhibitory and even toxic properties, which may be related to the protection of this tissue during development and germination, and might influence the nutritional valué of the cereal products. We report here the characterization in barley of cDNA clones encoding two major groups of proteins: the CM-proteins, a family that inciudes inhibitors of trypsin and a-amylase, and the thionins, a group of high-lysine toxic polypeptides

Characterization of interaction of magnetic nanoparticles with breast cancer cells

Background: Different superparamagnetic iron oxide nanoparticles have been tested for their potential use in cancer treatment, as they enter into cells with high effectiveness, do not induce cytotoxicity, and are retained for relatively long periods of time inside the cells. We have analyzed the interaction, internalization and biocompatibility of dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles with an average diameter of 15 nm and negative surface charge in MCF-7 breast cancer cells. Results: Cells were incubated with dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles for different time intervals, ranging from 0.5 to 72 h. These nanoparticles showed efficient internalization and relatively slow clearance. Time-dependent uptake studies demonstrated the maximum accumulation of dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles after 24 h of incubation, and afterwards they were slowly removed from cells. Superparamagnetic iron oxide nanoparticles were internalized by energy dependent endocytosis and localized in endosomes. Transmission electron microscopy studies showed macropinocytosis uptake and clathrin-mediated internalization depending on the nanoparticles aggregate size. MCF-7 cells accumulated these nanoparticles without any significant effect on cell morphology, cytoskeleton organization, cell cycle distribution, reactive oxygen species generation and cell viability, showing a similar behavior to untreated control cells. Conclusions: All these findings indicate that dimercaptosuccinic acid-coated superparamagnetic iron oxide nanoparticles have excellent properties in terms of efficiency and biocompatibility for application to target breast cancer cellsThe research leading to these results have received partial funding from the European Seventh Framework Programme (FP7/2007-2013) under the project MULTIFUN grant agreement no. 262943, and the project Nanofrontmag-CM (S2013/MIT-2850) from the Comunidad de Madrid. Additional grants were obtained from BFU 2011–29038 and CTQ2013-48767-C3-3-R from the Ministerio de Economia y Competitividad and S2009/Mat 1507 from the Comunidad de Madrid (to JLC), from EU FP7 project NAMDIATREAM (ref 246479) and from “la Caixa” / CNB International PhD Programme Fellowship

Viability of the biochar production from different manure wastes in the Amblés Valley (Ávila, Spain)

In the last years, intensive animal husbandry production has led to a large concentration of animals in small areas. This has resulted in the production of excessive amounts of manures with insufficient nearby land for application. One of this areas is the Amblés Valley located in the centre of Spain, near to Ávila city, with an extension of 167472 ha of which 88.9% is agricultural land. This valley has an important livestock focused on pig, cattle, chicken production which is associated with the generation of more than 200,000 t/year of manure. There are a number of environmental problems associated with these intensive agricultural systems, including N and P pollution of water bodies, methane emissions and odour pollution. These serious environmental threats are called for innovative environmental management approaches. A feasible technology for the management of manures, offering a potential to valorise these wastes, is pyrolysis, which results in the production of biochar. The objective of this work is evaluated the technical and economic feasibility of the production of biochar in Amblés Valley (Spain)