164 research outputs found
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
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
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
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
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
More pumas (Puma concolor) does not change perceptions: The mismatched response of ranchers to the presence of a top carnivore
The dataset that supports the findings of this study are archived in the Universidad Autónoma de Madrid data repository e‐cienciaDatos in https://doi.org/10.21950/IHY9VGHuman-wildlife conflicts (HWCs) are one of the most critical conservation challenges worldwide. Large carnivores are frequently at the centre of these conflicts because of the perceived and real threats they pose to livestock and human safety. Determining social perceptions and attitudes towards carnivores plays a vital role in shaping conservation policies that ensure the sustainable coexistence of humans and wildlife. We conducted structured interviews with livestock ranchers in the proposed Torres del Paine UNESCO Biosphere Reserve (Chilean Patagonia) in 2011 and 2018. We recorded information regarding their perceptions of puma presence, the potential danger pumas pose to livestock, livestock losses, and the need to control puma populations. We predicted puma distributions in both periods using MaxEnt to determine whether predicted puma presence explained ranchers' perceptions of pumas or any change in their perceptions over the course of the study. Puma distribution models predicted that the puma has expanded across the study area and that the likelihood of puma relative abundance within ranches increased over time. Despite this, ranchers did not change their perceptions of puma abundance or the losses they suffer from puma predation. Neither did they feel an increased need to manage the puma population. Furthermore, ranchers reported an increase in the perception that pumas are a threat to livestock in the second study period, but this perception was not linked to the likelihood of puma presence. We found a mismatch between the actual probability of puma presence and ranchers' perceptions, which remained mostly unchanged, suggesting that there are underlying social factors driving their perceptions about puma –livestock conflict regardless of actual puma presence and the losses they experience. Synthesis and applications. Results show that ranchers' perceptions are at odds with actual patterns of puma distribution. However, the increased perceived risks associated with puma's expansion would likely increase reported HWC. Given that the study area is home to what may be the densest puma population reported, and that some ranches benefit from puma-related tourism, while others bear the costs of increasing pumas in the region, the socioecological situation may be a conservation conundrum about to boilPartial support for UAM researchers was provided by Comunidad de Madrid \u2010Consejeria de Educacion e Investigacion\u2010 to the REMEDINAL TE\u2010CM Network (P2018/EMT\u20104338) and by Universidad de Chile
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
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