173 research outputs found

    Agricultural intensification erodes taxonomic and functional diversity in Mediterranean olive groves by filtering out rare species

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    Agri-Environmental Schemes (AES) have been proposed to mitigate the impact of agriculture on both taxonomic and functional biodiversity. However, a better knowledge of the mechanisms involved in the loss of agrobiodiversity is needed to implement efficient AES. An unbalanced effort on research towards arable lands compared to permanent crops, and on fauna relative to plants, is patent, which limits the generalization of AES effectiveness. We evaluated the effects of agricultural management and landscape simplification on taxonomic and functional diversity of the ground herb cover of 40 olive groves. We use a recently developed approach based on Hill numbers (rare, common and dominant species based) to analyse taxonomic and functional dissimilarity between farms with contrasting agricultural practices, and its potential attenuation by landscape complexity. We further explore the filtering effect of agricultural intensification on functional traits, and the relationship between functional and species richness across landscapes. We found that taxonomic and functional dissimilarity of herb assemblages between intensively and low-intensively managed fields was mainly due to rare species. Dissimilarity decreased as landscape complexity increased, evidencing that complex landscapes attenuate the impact of agriculture intensification on herb assemblage composition. Agricultural intensification favoured more functionally homogeneous assemblages and disfavoured the herbs pollinated by insects, while it did not seem to affect wind-pollinated species. Overall, functional richness increased exponentially with species richness across landscapes, but the latter was insufficient to drive any clear enhancement in functional richness in simple landscapes. In contrast, high species richness accelerated the enhancement in functional richness in intermediate and complex landscapes. These results highlight the functional filtering that intensive agriculture has generated for decades in homogeneous olive-dominated landscapes. Synthesis and applications. Herb cover is essential to support the fauna of permanent croplands and their sustainable production. Hence, Agri-Environmental Schemes (AES) in these croplands should promote management practices favouring the diversity and functionality of herb assemblages. Such AES should be particularly prioritized in homogeneous landscapes, where ground herb cover composition and function has long been homogenized to a great extent

    Nueva información para la avifauna del estado de Querétaro, México

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    We present new information about 24 species, including 12 noteworthy records for the avifauna of the Mexican state of Queretaro. These data were gathered during fieldwork performed between 1993 to 2007, mainly in the Eje NeovolcĂĄnico province. Five species are considered protected under Mexican law NOM-059-SEMARNAT-2001: Buteogallus anthracinus, Buteo albonotatus, Trogon collaris, Turdus infuscatus and Vermivora crissalis. The checklist of birds present in Queretaro is now at least 347 species.Presentamos informaciĂłn nueva de 24 especies, incluyendo 12 nuevos registros de aves para el estado de QuerĂ©taro, MĂ©xico. Estos datos fueron obtenidos en diversos estudios de campo de 1993 a 2007, principalmente en la provincia del Eje NeovolcĂĄnico. Cinco especies estĂĄn bajo alguna categorĂ­a de riesgo segĂșn la NOM-059-SEMARNAT-2001: Buteogallus anthracinus, Buteo albonotatus, Trogon collaris, Turdus infuscatus y Vermivora crissalis. Con estas adiciones el listado de aves de QuerĂ©taro se incrementa al menos a 347 especie

    Development of a research and innovation network on Fluoride and dental Fluorosis in latin america: Desenvolvimento da rede de pesquisa e inovação em FlĂșor e Fluorose dentĂĄria na amĂ©rica latina

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    Dental Fluorosis is a growing public health problem in many parts of the world. Dental Fluorosis in the world youngster population is increasing, as it is highlighted in the latest Latin American epidemiological report. There are few   studies on fluorosis and its prevalence in the region.  These are the basis for the creation of this international network, including Chile, Colombia, Ecuador, Paraguay and Argentina. In these countries there has been a significant increase in Dental Fluorosis, with values between 50% and 60%. A central goal of this network is to understand the “production-consumption source”, environment and the monitoring of systemic fluoride exposure, key to promote the benefits of fluorides and minimize the risks of chronic overexposure, leading to fluorosis. The significant increase in fluorosis in the Latin American region led to the formation of this research network. Its aim is to create a network of research centers in Latin America based on the management of spaces for communication, exchange and generation of knowledge on the subject of fluorides and dental fluorosis, and to generate products that can be used as inputs for public policy in the national health systems of the countries

    Polyphenolic Profile, Sugar Consumption and Organic Acids Generation along Fermentation of Infusions from Guava (Pisidium guajava) by the Kombucha Consortium

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    The kombucha beverage is typically prepared from black tea, sweetened with sucrose, inoculated with previously fermented liquid broth and/or tea fungus pellicle, and incubated. Alternative sources have been used for kombucha beverages. Guava leaves have been used for long time as traditional medicine. It is found in many commercially available botanical supplements in form of decoction, milled and used as comprises. They are rich in polyphenolic compounds. Several changes are produced during fermentation of the beverages. The main objective of the present work is to characterize fermentation process of guava leaves infusions by kombucha and studying possible chemical changes in their polyphenolic profile. Infusions from guava leaves were prepared and fermented by the kombucha consortium. The pH, titrable acidity, polyphenolic compounds, sugar consumption, organic acid along the fermentation was made by UPLC-ESI-MS. Kombucha from Camellia sinensis (CS) was made as a control. Higher rate of sucrose consumption was observed for Kombucha made with CS, also, higher production of organic acids (acetic and succinic acid) was observed too. Both behaviors were related to the content of glucose. The flavan-3-ols were diminishing along the fermentation time, with the exception of epigallocatechin in Camellia sinensis, Flavan-3-ol content in Guava leaves was low. Higher content of dicaffeoyl quinnic acid was observed for both systems in special for CS, falling after a maximum peak; minor constituents of hydroxycinnamic acids were stable along the fermentation for both systems

    Exhaustion of mitochondrial and autophagic reserve may contribute to the development of LRRK2 G2019S -Parkinson's disease

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    BACKGROUND: Mutations in leucine rich repeat kinase 2 (LRRK2) are the most common cause of familial Parkinson's disease (PD). Mitochondrial and autophagic dysfunction has been described as etiologic factors in different experimental models of PD. We aimed to study the role of mitochondria and autophagy in LRRK2 G2019S -mutation, and its relationship with the presence of PD-symptoms. METHODS: Fibroblasts from six non-manifesting LRRK2 G2019S -carriers (NM-LRRK2 G2019S ) and seven patients with LRRK2 G2019S -associated PD (PD-LRRK2 G2019S ) were compared to eight healthy controls (C). An exhaustive assessment of mitochondrial performance and autophagy was performed after 24-h exposure to standard (glucose) or mitochondrial-challenging environment (galactose), where mitochondrial and autophagy impairment may be heightened. RESULTS: A similar mitochondrial phenotype of NM-LRRK2 G2019S and controls, except for an early mitochondrial depolarization (54.14% increased, p = 0.04), was shown in glucose. In response to galactose, mitochondrial dynamics of NM-LRRK2 G2019S improved (- 17.54% circularity, p = 0.002 and + 42.53% form factor, p = 0.051), probably to maintain ATP levels over controls. A compromised bioenergetic function was suggested in PD-LRRK2 G2019S when compared to controls in glucose media. An inefficient response to galactose and worsened mitochondrial dynamics (- 37.7% mitochondrial elongation, p = 0.053) was shown, leading to increased oxidative stress. Autophagy initiation (SQTSM/P62) was upregulated in NM-LRRK2 G2019S when compared to controls (glucose + 118.4%, p = 0.014; galactose + 114.44%, p = 0.009,) and autophagosome formation increased in glucose media. Despite of elevated SQSTM1/P62 levels of PD-NM G2019S when compared to controls (glucose + 226.14%, p = 0.04; galactose + 78.5%, p = 0.02), autophagosome formation was deficient in PD-LRRK2 G2019S when compared to NM-LRRK2 G2019S (- 71.26%, p = 0.022). CONCLUSIONS: Enhanced mitochondrial performance of NM-LRRK2 G2019S in mitochondrial-challenging conditions and upregulation of autophagy suggests that an exhaustion of mitochondrial bioenergetic and autophagic reserve, may contribute to the development of PD in LRRK2 G2019S mutation carriers

    Mitochondrial and autophagic alterations in skin fibroblasts from Parkinson disease patients with Parkin mutations.

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    PRKN encodes an E3-ubiquitin-ligase involved in multiple cell processes including mitochondrial homeostasis and autophagy. Previous studies reported alterations of mitochondrial function in fibroblasts from patients with PRKN mutation-associated Parkinson's disease (PRKN-PD) but have been only conducted in glycolytic conditions, potentially masking mitochondrial alterations. Additionally, autophagy flux studies in this cell model are missing.We analyzed mitochondrial function and autophagy in PRKN-PD skin-fibroblasts (n=7) and controls (n=13) in standard (glucose) and mitochondrial-challenging (galactose) conditions.In glucose, PRKN-PD fibroblasts showed preserved mitochondrial bioenergetics with trends to abnormally enhanced mitochondrial respiration that, accompanied by decreased CI, may account for the increased oxidative stress. In galactose, PRKN-PD fibroblasts exhibited decreased basal/maximal respiration vs. controls and reduced mitochondrial CIV and oxidative stress compared to glucose, suggesting an inefficient mitochondrial oxidative capacity to meet an extra metabolic requirement. PRKN-PD fibroblasts presented decreased autophagic flux with reduction of autophagy substrate and autophagosome synthesis in both conditions.The alterations exhibited under neuron-like oxidative environment (galactose), may be relevant to the disease pathogenesis potentially explaining the increased susceptibility of dopaminergic neurons to undergo degeneration. Abnormal PRKN-PD phenotype supports the usefulness of fibroblasts to model disease and the view of PD as a systemic disease where molecular alterations are present in peripheral tissues

    Selecciones del blog de AEMET 2022

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    Contiene: ÂżFĂ­sica de fluidos o cabañuelas? / Delia GutiĂ©rrez Rubio -- ÂżQuĂ© podemos contarte en AEMET sobre la sequĂ­a? / Delia GutiĂ©rrez Rubio -- Patrones sinĂłpticos en la penĂ­nsula ibĂ©rica y Baleares y su relaciĂłn con los incendios forestales / Peio Oria Iriarte -- ÂżTemperaturas al sol y a la sombra? ÂżCĂłmo se mide la temperatura en una estaciĂłn meteorolĂłgica? / Ricardo Torrijo Murciano, Alejandro Lomas GonzĂĄlez y JosĂ© Antonio LĂłpez DĂ­az -- Verano de 2022: el mĂĄs cĂĄlido en España hasta finales de julio / JosĂ© Ángel NĂșñez Mora y RubĂ©n del Campo HernĂĄndez -- El invierno nuclear / Benito JosĂ© Fuentes LĂłpez -- ÂżCĂłmo se mueven los ocĂ©anos y cĂłmo influye esto en el clima? / Enrique FernĂĄndez Barrera

    Disrupted mitochondrial and metabolic plasticity underlie comorbidity between age-Related and degenerative disorders as parkinson disease and type 2 diabetes mellitus.

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    Idiopathic Parkinson's disease (iPD) and type 2 diabetes mellitus (T2DM) are chronic, multisystemic, and degenerative diseases associated with aging, with eventual epidemiological co-morbidity and overlap in molecular basis. This study aims to explore if metabolic and mitochondrial alterations underlie the previously reported epidemiologic and clinical co-morbidity from a molecular level. To evaluate the adaptation of iPD to a simulated pre-diabetogenic state, we exposed primary cultured fibroblasts from iPD patients and controls to standard (5 mM) and high (25 mM) glucose concentrations to further characterize metabolic and mitochondrial resilience. iPD fibroblasts showed increased organic and amino acid levels related to mitochondrial metabolism with respect to controls, and these differences were enhanced in high glucose conditions (citric, suberic, and sebacic acids levels increased, as well as alanine, glutamate, aspartate, arginine, and ornithine amino acids; p-values between 0.001 and 0.05). The accumulation of metabolites in iPD fibroblasts was associated with (and probably due to) the concomitant mitochondrial dysfunction observed at enzymatic, oxidative, respiratory, and morphologic level. Metabolic and mitochondrial plasticity of controls was not observed in iPD fibroblasts, which were unable to adapt to different glucose conditions. Impaired metabolism and mitochondrial activity in iPD may limit energy supply for cell survival. Moreover, reduced capacity to adapt to disrupted glucose balance characteristic of T2DM may underlay the co-morbidity between both diseases. Conclusions: Fibroblasts from iPD patients showed mitochondrial impairment, resulting in the accumulation of organic and amino acids related to mitochondrial metabolism, especially when exposed to high glucose. Mitochondrial and metabolic defects down warding cell plasticity to adapt to changing glucose bioavailability may explain the comorbidity between iPD and T2DM

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

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    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file
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