11 research outputs found
Evolutionary coordination system for fixed-wing communications unmanned aerial vehicles
A system to coordinate the movement of a group of un- manned aerial vehicles that provide a network backbone over mobile ground-based vehicles with communication needs is presented. Using evo- lutionary algorithms, the system evolves flying manoeuvres that position the aerial vehicles by fulfilling two key requirements; i) they maximise net coverage and ii) they minimise the power consumption. Experimental results show that the proposed coordination system is able to offer a de- sirable level of adaptability with respect to the objectives set, providing useful feedback for future research directions
Regulatory RNAs and chromatin modification in dosage compensation: A continuous path from flies to humans?
Chromosomal sex determination is a widely distributed strategy in nature. In the most classic scenario, one sex is characterized by a homologue pair of sex chromosomes, while the other includes two morphologically and functionally distinct gonosomes. In mammalian diploid cells, the female is characterized by the presence of two identical X chromosomes, while the male features an XY pair, with the Y bearing the major genetic determinant of sex, i.e. the SRY gene. In other species, such as the fruitfly, sex is determined by the ratio of autosomes to X chromosomes. Regardless of the exact mechanism, however, all these animals would exhibit a sex-specific gene expression inequality, due to the different number of X chromosomes, a phenomenon inhibited by a series of genetic and epigenetic regulatory events described as "dosage compensation". Since adequate available data is currently restricted to worms, flies and mammals, while for other groups of animals, such as reptiles, fish and birds it is very limited, it is not yet clear whether this is an evolutionary conserved mechanism. However certain striking similarities have already been observed among evolutionary distant species, such as Drosophila melanogaster and Mus musculus. These mainly refer to a) the need for a counting mechanism, to determine the chromosomal content of the cell, i.e. the ratio of autosomes to gonosomes (a process well understood in flies, but still hypothesized in mammals), b) the implication of non-translated, sex-specific, regulatory RNAs (roX and Xist, respectively) as key elements in this process and the location of similar mediators in the Z chromosome of chicken c) the inclusion of a chromatin modification epigenetic final step, which ensures that gene expression remains stably regulated throughout the affected area of the gonosome. This review summarizes these points and proposes a possible role for comparative genetics, as they seem to constitute proof of maintained cell economy (by using the same basic regulatory elements in various different scenarios) throughout numerous centuries of evolutionary history
Socially and biologically inspired computing for self-organizing communications networks
The design and development of future communications networks call for a careful examination of biological and social systems. New technological developments like self-driving cars, wireless sensor networks, drones swarm, Internet of Things, Big Data, and Blockchain are promoting an integration process that will bring together all those technologies in a large-scale heterogeneous network. Most of the challenges related to these new developments cannot be faced using traditional approaches, and require to explore novel paradigms for building computational mechanisms that allow us to deal with the emergent complexity of these new applications. In this article, we show that it is possible to use biologically and socially inspired computing for designing and implementing self-organizing communication systems. We argue that an abstract analysis of biological and social phenomena can be made to develop computational models that provide a suitable conceptual framework for building new networking technologies: biologically inspired computing for achieving efficient and scalable networking under uncertain environments; socially inspired computing for increasing the capacity of a system for solving problems through collective actions. We aim to enhance the state-of-the-art of these approaches and encourage other researchers to use these models in their future work
Advancing evolutionary coordination for fixed-wing communications UAVs
In this paper we present advances to our previously proposed coordination system for groups of unmanned aerial vehicles that provide a network backbone over mobile ground-based vehicles. Evolutionary algorithms are employed in order to evolve flying manoeuvres that position the aerial vehicles. The updates to the system include obstacle representation, a packing mechanism to permit efficient dynamic allocation of ground-based vehicles to their supporting aerial vehicles within large-scale environments, and changes to time synchronisation. The experimental results presented in this paper show that the system is able to adaptively form sparse formations that cover as many ground-based vehicles as possible, optimising the use of the available power
Evaluation of diagnostic algorithm and therapeutic interventions for intra-abdominal desmoid tumors
Desmoid-type fibromatosis (DF) is a distinctly rare condition, mostly of younger adults, characterized by the development of locally aggressive tumors of mesenchymal origin. Desmoid tumors (DT) arise either sporadically or in association with FAP (familial adenomatous polyposis), although certain risk factors have also been identified, including pregnancy and antecedent surgical trauma. They can emerge from any connective tissue including muscle, fascia and aponeurosis and are therefore classified, according to location, as intra-abdominal, of the abdominal wall and extra-abdominal. Despite the lack of metastasizing potential, the course can be unpredictable. Various mutations of APC and β-catenin genes, among others, play a catalytic role in the pathogenesis of this neoplastic entity. Surgery has lost its traditional role as first line treatment of the disease and several other treatment methods are being considered. Cytotoxic chemotherapy, non-cytotoxic systemic therapy and targeted therapy have been revealed as part of different treatment regimens. Recent progress regarding DT biology and molecular pathways has led to the development of promising novel biological agents. In any case, a multidisciplinary approach is required and is gradually employed, espe-cially in intra-abdominal DTs. In this review, we aim to present current knowledge on DF and summarize current treatment regimens as well as their effectiveness, with emphasis on the intraperitoneal type of DT. © 2022 Elsevier Lt
Particle Swarm Based Resource Optimized Geographic Routing for Improved Network Lifetime in MANET
Fish consumption patterns and hair mercury levels in children and their mothers in 17 EU countries
The toxicity of methylmercury (MeHg) in humans is well established and the main source of exposure is via the consumption of large marine fish and mammals. Of particular concern are the potential neurodevelopmental effects of early life exposure to low-levels of MeHg. Therefore, it is important that pregnant women, children and women of childbearing age are, as far as possible, protected from MeHg exposure. Within the European project DEMOCOPHES, we have analyzed mercury (Hg) in hair in 1799 mother-child pairs from 17 European countries using a strictly harmonized protocol for mercury analysis. Parallel, harmonized questionnaires on dietary habits provided information on consumption patterns of fish and marine products. After hierarchical cluster analysis of consumption habits of the mother-child pairs, the DEMOCOPHES cohort can be classified into two branches of approximately similar size: one with high fish consumption (H) and another with low consumption (L). All countries have representatives in both branches, but Belgium, Denmark, Spain, Portugal and Sweden have twice as many or more mother-child pairs in H than in L. For Switzerland, Czech Republic, Hungary, Poland, Romania, Slovenia and Slovakia the situation is the opposite, with more representatives in L than H. There is a strong correlation (r=0.72) in hair mercury concentration between the mother and child in the same family, which indicates that they have a similar exposure situation. The clustering of mother-child pairs on basis of their fish consumption revealed some interesting patterns. One is that for the same sea fish consumption, other food items of marine origin, like seafood products or shellfish, contribute significantly to the mercury levels in hair. We conclude that additional studies are needed to assess and quantify exposure to mercury from seafood products, in particular. The cluster analysis also showed that 95% of mothers who consume once per week fish only, and no other marine products, have mercury levels 0.55μg/g. Thus, the 95th percentile of the distribution in this group is only around half the US-EPA recommended threshold of 1μg/g mercury in hair. Consumption of freshwater fish played a minor role in contributing to mercury exposure in the studied cohort. The DEMOCOPHES data shows that there are significant differences in MeHg exposure across the EU and that exposure is highly correlated with consumption of fish and marine products. Fish and marine products are key components of a healthy human diet and are important both traditionally and culturally in many parts of Europe. Therefore, the communication of the potential risks of mercury exposure needs to be carefully balanced to take into account traditional and cultural values as well as the potential health benefits from fish consumption. European harmonized human biomonitoring programs provide an additional dimension to national HMB programs and can assist national authorities to tailor mitigation and adaptation strategies (dietary advice, risk communication, etc.) to their country's specific requirements.publisher: Elsevier
articletitle: Fish consumption patterns and hair mercury levels in children and their mothers in 17 EU countries
journaltitle: Environmental Research
articlelink: http://dx.doi.org/10.1016/j.envres.2014.10.029
content_type: article
copyright: Copyright © 2014 The Authors. Published by Elsevier Inc.status: publishe