123 research outputs found
Geometric reduction in optimal control theory with symmetries
A general study of symmetries in optimal control theory is given, starting
from the presymplectic description of this kind of system. Then, Noether's
theorem, as well as the corresponding reduction procedure (based on the
application of the Marsden-Weinstein theorem adapted to the presymplectic case)
are stated both in the regular and singular cases, which are previously
described.Comment: 24 pages. LaTeX file. The paper has been reorganized. Additional
comments have been included in Section 3. The example in Section 5.2 has been
revisited. Some references have been adde
Characterization of the plankton community composition in Málaga Bay (NW Alboran Sea) by means of integrative taxonomy.
The Alboran Sea is highly dynamic from a hydrographical point of view. Depending on the strength of the currents and the direction of the wind the surface coastal water masses can be either of Atlantic or Mediterranean origin. This variability affects both the phytoplankton and zooplankton components of the community inhabiting the Bay of Málaga. In addition, fish larvae distribution varies with the diel cycle, affecting zooplankton distribution in shallow waters. In order to provide a first insight into the variability of the planktonic community composition in the area during a 24 hour cycle, we applied an integrative approach combining morphological and molecular tools
Dissection of ancestral genetic contributions to Creole goat populations
Goats have played a key role as source of nourishment for humans in their expansion all over the world in long land and sea trips. This has guaranteed a place for this species in the important and rapid episode of livestock expansion triggered by Columbus’ arrival in the Americas in the late 1400s. The aims of this study are to provide a comprehensive perspective on genetic diversity in American goat populations and to assess their origins and evolutionary trajectories. This was achieved by combining data from autosomal neutral genetic markers obtained in more than two thousand samples that encompass a wide range of Iberian, African and Creole goat breeds. In general, even though Creole populations differ clearly from each other, they lack a strong geographical pattern of differentiation, such that populations of different admixed ancestry share relatively close locations throughout the large geographical range included in this study. Important Iberian signatures were detected in most Creole populations studied, and many of them, particularly the Cuban Creole, also revealed an important contribution of African breeds. On the other hand, the Brazilian breeds showed a particular genetic structure and were clearly separated from the other Creole populations, with some influence from Cape Verde goats. These results provide a comprehensive characterisation of the present structure of goat genetic diversity, and a dissection of the Iberian and African influences that gave origin to different Creole caprine breeds, disentangling an important part of their evolutionary history. Creole breeds constitute an important reservoir of genetic diversity that justifies the development of appropriate management systems aimed at improving performance without loss of genomic diversity
Long-term evolution of the neutron rate at the Canfranc Underground Laboratory
We report results on the long-term variation of the neutron counting rate at
the Canfranc Underground Laboratory, of importance for several low-background
experiments installed there, including rare-event searches. The measurement
campaign was performed employing the High Efficiency Neutron Spectrometry Array
(HENSA) mounted in Hall A and lasted 412 live days. The present study is the
first long-term measurement of the neutron rate with sensitivity over a wide
range of neutron energies (from thermal up to 0.1 GeV and beyond) performed in
any underground laboratory so far. Data on the environmental variables inside
the experimental hall (radon concentration, air temperature, air pressure and
humidity) were also acquired during all the measurement campaign. We have
investigated for the first time the evolution of the neutron rate for different
energies of the neutrons and its correlation with the ambient variables.Comment: 12 pages, 5 figures, 2 table
Molecular characterization of the diet of the planktonic community in Málaga Bay (NW Alboran Sea)
The seasonal changes in structure and functioning of the pelagic trophic web in Málaga Bay (NW Alboran Sea) are related to the annual hydrological cycle. However, time series analyses have shown that the relationship between interannual hydrological variability and the plankton community composition is weak. This might be due to different human-induced pressures (nutrient pollution, coastal fisheries) acting on different compartments of the trophic web. The net effect of all these factors would depend on how the ecosystem channels changes in the composition and abundance of each trophic level. Interactions of phytoplankton-ciliates-zooplankton might have a central role in the regulation of the trophic web in Málaga Bay, although the trophic relations of the dominant groups remain still undefined. In order to identify the dominant trophic relationships we aimed to characterise the diet of key ichthyo- and mesozooplankton species in the field. Given that gut content preys (phyto- and microplankton) are fragile and not easy to identify visually, we developed species-specific molecular markers to detect their presence/absence within the predators gut
Relaciones entre los bovinos criollos panameños y algunas razas criollas de Latinoamérica
First results from the HENSA/ANAIS collaboration at the Canfranc Underground Laboratory
The HENSA/ANAIS collaboration aims for the precise determination of the neutron flux that could affect ANAIS-112, an experiment looking for the dark matter annual modulation using NaI(Tl) scintillators. In this work, the first measurements of the neutron flux and Monte Carlo simulations of the neutron spectrum are reported
Role of small-sized phytoplankton in triggering an ecosystem disruptive algal bloom in a Mediterranean hypersaline coastal lagoon
Preprint2,35
Towards a life cycle sustainability assessment method for the quantification and reduction of impacts of buildings life cycle
The construction and building sectorsare one of the highestconsumersof resourcesand energy. Literature evidences the potentialities of the design phase towardsthe improvement of environmental, economic and social performance of buildings. Thus, the Life Cycle Sustainability Assessment (LCSA) approach is
recognized as suitable method. It isbased on the “triple bottom line”principle, to calculate environmental, economic, social impacts produced by buildings during itslife cycle. The present paper aims to present
a methodological framework based on anLCSA, used during design stages of buildings and integrated into a building’s design technology such as Building Information Modeling (BIM). A conceptual approach to conduct
the data integration and a possible workflow to integrate the LCSA into BIMis proposed. The value of the present approach is the possibility to conductquantitative environmental, economic and social assessment
of buildings to guide designers to measure and predict the building’s performanc
On the origins of American Criollo pigs: A common genetic background with a lasting Iberian signature
American Criollo pigs are thought to descend mainly from those imported from the Iberian Peninsula starting in the late 15th century. Criollo pigs subsequently expanded throughout the Americas, adapting to very diverse environments, and possibly receiving influences from other origins. With the intensification of agriculture in the mid-20th century, cosmopolitan breeds largely replaced Criollo pigs, and the few remaining are mostly maintained by rural communities in marginal areas where they still play an important socio-economic and cultural role. In this study, we used 24 microsatellite markers in samples from 1715 pigs representing 46 breeds with worldwide distribution, including 17 American Criollo breeds, with the major focus of investigating their genetic diversity, structure and breed relationships. We also included representatives of the Iberian, Local British, Hungarian, Chinese and Commercial breeds, as well as Wild Boar, in order to investigate their possible influence in the genetic composition of Criollos. Our results show that, when compared with the other breeds, Criollo pigs present higher levels of genetic diversity, both in terms of allelic diversity and expected heterozygosity. The various analyses indicate that breed differentiation overall explains nearly 21% of the total genetic diversity. Criollo breeds showed their own identity and shared a common genetic background, tending to cluster together in various analyses, even though they differ from each other. A close relationship of Criollos with Iberian breeds was revealed by all the different analyses, and the contribution of Iberian breeds, particularly of the Celtic breeds, is still present in various Criollo breeds. No influence of Chinese breeds was detected on Criollos, but a few were influenced by Commercial breeds or by wild pigs. Our results confirm the uniqueness of American Criollo pigs and the role that Iberian breeds have played in their development. © 2021 Revidatti et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
- …