Relative pose determination algorithm for space on-orbit close range autonomous operation using LiDAR

Non cooperative on-orbit operations, such as rendezvous, docking or berthing operations, have become more relevant, mainly due to the necessity of expanding mission lifetimes, the increase of space debris and the reduction of human dependency. In order to automate these operations, the relative pose calculation between the target and the chaser must be determined autonomously. In recent years, LiDAR sensors have been introduced for this problem, achieving good accuracies. The critical part of this operation is the first relative pose calculation, since there is no previous information about the attitude of the target. In this work, a methodology to carry out this first relative pose calculation using LiDAR sensors is presented. A template matching algorithm has been developed, which uses the 3D model of the target to calculate the relative pose of the target regarding the LiDAR sensor. Three different study cases, with different distances and rotations, have been simulated in order to validate the algorithm, reaching an average error of 0.0383m

Effort needed to accurately estimate Vocal Activity Rate index using acoustic monitoring: A case study with a dawn-time singing passerine

Los autores del Departamento de Ecología de la UAM pertenecen al Terrestrial Ecology Group (TEG-UAM)Indices based on singing activity have often been used in wildlife surveys conducted with passive acoustic monitoring. For instance, the Vocal Activity Rate index (VAR) has been employed to estimate animal populations and detect changes in abundance between years or sites. VAR may differ greatly between days due to environmental and biological factors, therefore leading to inadequate population size estimations and recommendations. However, there is still little information about the minimum number of monitoring days required for estimating a reliable VAR to assess changes over time or sites. We describe, for first time for a terrestrial bird species, the pattern of variation of VAR as a function of the number of monitoring days. Coefficient of variation sharply decreased with the number of monitoring days, and this pattern was similar during the breeding and post-breeding period. Coefficient of variation was close to 100% when a single monitoring day was surveyed, but decreased up to 30% and 20% after six or seven and nine monitoring days, depending on the monitoring period. Mean VAR was significantly related to bird abundance, but no relationship was found between bird abundance and number of days needed to reach a CV lower than 20%. Our results highlight that prior assessment of effort needed to estimate a reliable VAR should be a prerequisite for future monitoring programmes using singing activity indices. We found large differences in the number of monitoring days needed to obtain a reliable VAR in comparison to prior research on seabirds, suggesting that further research should be developed in different taxa and situationsThis is a contribution to the LIFE Ricoti (LIFE15-NAT-ES-000802), supported by the European Commission, the “BBVA-Dron Ricoti”, funded by the BBVA Foundation and the Excellence Network Remedinal 3CM (S2013/MAE2719), supported by Comunidad de Madri

Resource partitioning and niche segregation in a steppe bird assemblage

Niche theory predicts that coexisting species will partition resources to limit the effects of interspecific competition. We examined microhabitat partitioning in six sets of steppe birds associated to agroecosystems in central Spain (female and male Great Bustards Otis tarda, female and male Little Bustards Tetrax tetrax, Red-legged Partridges Alectoris rufa and Eurasian Stone-curlews Burhinus oedicnemus) to estimate realized niche breadth, overlap and segregation. Principal Components Analysis on data from used and random microhabitat locations produced two axes we retained for analysis related with two key factors: cover-visibility and food availability. Non-parametric kernel density functions were calculated for each of the PCA axes and species (or sexes), and niche overlap estimated as the area shared between species’ density functions. Null models were run to evaluate overlap significance. In analyses of microhabitat selection by the six sets of birds, 13 out of 15 pairs had significant resource partitioning and niche segregation, except for the pairs partridge and female Great Bustard and the two sexes of Great Bustard. Eurasian Stone-curlew showed wider trophic niche breadth, although segregated from the other species, probably because of its higher invertebrate requirements. Great and Little Bustards segregated in both niche axes, selecting microhabitat according to their body size. Accessibility to food resources and shelter seems to be similar for partridges and female Great Bustards, overlapping in their selection, which may indicate the existence of segregation in other niche factors (e.g., feeding habits). Great Bustard males showed niche overlap with females. Little Bustard males showed feeding microhabitat selection patterns similar to those of females, although they preferred more open microhabitats to meet their sexual display requirements. The entire assemblage had significantly less overlap than expected by chance, suggesting that differential microhabitat selection and realized niche partitioning may explain coexistence in steppe bird communities. Our results suggest that the maintenance of different microhabitat structure should be a priority in the management of agricultural environments

Comparative assessment of satellite- and drone-based vegetation indices to predict arthropod biomass in shrub-steppes

Arthropod biomass is a key element in ecosystem functionality and a basic food item for many species. It must be estimated through traditional costly field sampling, normally at just a few sampling points. Arthropod biomass and plant productivity should be narrowly related because a large majority of arthropods are herbivorous, and others depend on these. Quantifying plant productivity with satellite or aerial vehicle imagery is an easy and fast procedure already tested and implemented in agriculture and field ecology. However, the capability of satellite or aerial vehicle imagery for quantifying arthropod biomass and its relationship with plant productivity has been scarcely addressed. Here, we used unmanned aerial vehicle (UAV) and satellite Sentinel-2 (S2) imagery to establish a relationship between plant productivity and arthropod biomass estimated through ground-truth field sampling in shrub steppes. We UAV-sampled seven plots of 47.6–72.3 ha at a 4-cm pixel resolution, subsequently downscaling spatial resolution to 50 cm resolution. In parallel, we used S2 imagery from the same and other dates and locations at 10-m spatial resolution. We related several vegetation indices (VIs) with arthropod biomass (epigeous, coprophagous, and four functional consumer groups: predatory, detritivore, phytophagous, and diverse) estimated at 41–48 sampling stations for UAV flying plots and in 67–79 sampling stations for S2. VIs derived from UAV were consistently and positively related to all arthropod biomass groups. Three out of seven and six out of seven S2-derived VIs were positively related to epigeous and coprophagous arthropod biomass, respectively. The blue normalized difference VI (BNDVI) and enhanced normalized difference VI (ENDVI) showed consistent and positive relationships with arthropod biomass, regardless of the arthropod group or spatial resolution. Our results showed that UAV and S2-VI imagery data may be viable and cost-efficient alternatives for quantifying arthropod biomass at large scales in shrub steppes. The relationship between VI and arthropod biomass is probably habitat-dependent, so future research should address this relationship and include several habitats to validate VIs as proxies of arthropod biomassBBVA Foundation, BBVA Dron Ricoti project; European Commission, Grant/ Award Number: LIFE15-NAT-ES-000802; REMEDINAL-3 from CAM; European Comission, Grant/Award Number: LIFE20-NAT-ES-00013

Esquema para la gestión financiera del desarrollo local

Se propuso un esquema para la administración eficiente de los recursos financieros que potencien la gestión del desarrollo local. Se abordaron en el territorio los mecanismos para la administración de los recursos financieros; el proceso de administración financiera; las principales limitantes de la gestión del proceso de inversión y financiación de las estrategias de desarrollo; las potencialidades, necesidades, y posibles sinergias del sistema empresarial en la búsqueda de ingresos endógenos en la localidad y se determinó el requerimiento financiero para materializar una estrategia de planificación financiera local. El esquema permitió la aplicación de un sistema coherente de procedimientos sobre la base de las funciones fundamentales de la administración financiera y propició la articulación con el proceso administrativo de forma general. Se concluyó que la administración financiera juega un papel decisivo dentro del proceso de dirección. Se trata no sólo de "administrar las finanzas”; sino también de "administrar a través de las finanzas" con el fin de contribuir a la gestión del financiamiento del desarrollo local

The Suppressor of AAC2 Lethality SAL1 Modulates Sensitivity of Heterologously Expressed Artemia ADP/ATP Carrier to Bongkrekate in Yeast

The ADP/ATP carrier protein (AAC) expressed in Artemia franciscana is refractory to bongkrekate. We generated two strains of Saccharomyces cerevisiae where AAC1 and AAC3 were inactivated and the AAC2 isoform was replaced with Artemia AAC containing a hemagglutinin tag (ArAAC-HA). In one of the strains the suppressor of ΔAAC2 lethality, SAL1, was also inactivated but a plasmid coding for yeast AAC2 was included, because the ArAACΔsal1Δ strain was lethal. In both strains ArAAC-HA was expressed and correctly localized to the mitochondria. Peptide sequencing of ArAAC expressed in Artemia and that expressed in the modified yeasts revealed identical amino acid sequences. The isolated mitochondria from both modified strains developed 85% of the membrane potential attained by mitochondria of control strains, and addition of ADP yielded bongkrekate-sensitive depolarizations implying acquired sensitivity of ArAAC-mediated adenine nucleotide exchange to this poison, independent from SAL1. However, growth of ArAAC-expressing yeasts in glycerol-containing media was arrested by bongkrekate only in the presence of SAL1. We conclude that the mitochondrial environment of yeasts relying on respiratory growth conferred sensitivity of ArAAC to bongkrekate in a SAL1-dependent manner. © 2013 Wysocka-Kapcinska et al

Carga tributaria territorial: herramienta de análisis y contribución financiera al desarrollo local

Se analizó la carga tributaria como herramienta de estudio y control para el gobierno local, en función de las decisiones de financiamiento para el desarrollo de los territorios. Se estudió la carga tributaria territorial como elemento clave para la captación de ingresos por concepto de tributos y a su vez su relación con el valor agregado territorial. Así, el elemento estudiado —desde la gestión financiera de gobierno— puede contribuir a la satisfacción de las necesidades reales de desarrollo local. Se partió de un enfoque totalmente analítico de las principales dificultades, tanto de la gestión tributaria en su conjunto como de su vinculación con la gestión estratégica del territorio. Se propone un esquema lógico, descriptor de los pasos para determinar (y analizar) la carga tributaria territorial, en el cual se considera este proceso, no desde la oficina tributaria, sino desde el gobierno local. Éste —con su alcance en la toma de decisiones—, puede utilizar esta herramienta de análisis para intervenir en las principales dificultades en la captación de ingresos por concepto de impuestos que se revertirán en financiamiento para el desarrollo local

Interactions in shrubsteppes: Implications for the maintenance of a threatened bird

The interactions between ecosystem components and their implications on birds have been poorly studied, especially in shrubsteppes. In this work, we evaluate the interactions between vegetation structure, arthropods availability and the use of space by the Dupont's lark (Chersophilus duponti) in important areas for the species in the Iberian Peninsula. To that end, between 20152018 springs, bird censuses and microhabitat samples were carried out in suitable areas for the species, which should be taken as a reference for habitat restoration tasks. The intensity of space use by the species was calculated by a kernel density function, which defines the probability of finding a territory from the spatial pattern of observations. The habitat quality was determined by sampling vegetation structure and food availability. Habitat structure variables were summarized by principal component analysis. Linear mixed models (LMMs) were adjusted to evaluate the relationships between variables. Shrub cover was positively and significantly related to total epigeous biomass and Coleoptera biomass, and positive but marginally significant with hypogeous biomass (mainly arthropods larvae). The biomass of order Araneae was positively and significantly related to the use of space by Dupont's lark, while total epigeous biomass and Coleoptera biomass were positively but marginally related to the use of space by Dupont's lark. This work provides new results about habitat and its quality for Dupont's lark in optimal habitat for the species, and it highlight the fundamental role of arthropod availability for the maintenance of the species which has to be taken into account in carrying out restoration actions for the speciesEste trabajo se ha realizado gracias a la Oficina de Educación, Juventud y Deporte (Comunidad de Madrid) y el Fondo Social Europeo para la Iniciativa de Empleo Juvenil (PEJD-2018-PRE/AMB-8063); el proyecto Life-Ricotí (LIFE15-NATES-000802), otorgado por la Comisión Europea; el proyecto BBVADron-Ricotí, otorgado por la Fundación BBV

Reconciling livestock production and wild herbivore conservation: challenges and opportunities

Increasing food security and preventing further loss of biodiversity are two of humanity’s most pressing challenges. Yet, efforts to address these challenges often lead to situations of conflict between the interests of agricultural production and those of biodiversity conservation. Here, we focus on conflicts between livestock production and the conservation of wild herbivores, which have received little attention in the scientific literature. We identify four key socio-ecological challenges underlying such conflicts, which we illustrate using a range of case studies. We argue that addressing these challenges will require the implementation of co-management approaches that promote the participation of relevant stakeholders in processes of ecological monitoring, impact assessment, decision-making, and active knowledge sharing

Changes in grassland management and linear infrastructures associated to the decline of an endangered bird population

European grassland birds are experiencing major population declines, mainly due to changes in farmland management. We analyzed the role of habitat availability, grazing management and linear infrastructures (roads and power lines) in explaining spatial and temporal variation in the population density of little bustards (Tetrax tetrax) in Portugal, during a decade in which the species population size halved. We used data from 51 areas (totaling ca. 1,50,000 ha) that were sampled in two different periods (2003–2006 and 2016). In 2003–2006, when the species occurred at high densities, habitat availability was the only factor affecting spatial variation in bustard density. In the 2016 survey, variation in density was explained by habitat availability and livestock management, with reduced bird numbers in areas with higher proportions of cattle. Population declines across the study period were steeper in areas that initially held higher densities of bustards and in areas with a higher proportion of cattle in the total stocking rate. Areas with higher densities of power lines also registered greater density declines, probably due to avoidance behavior and to increased mortality. Overall, our results show little bustards are currently lacking high quality grassland habitat, whose persistence depends on extensive grazing regimes and low linear infrastructure densitiesinfo:eu-repo/semantics/publishedVersio