433 research outputs found

    Molluscs as bioindicators of the regression of a Zostera marina bed in southern Spain

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    Seagrass beds are experiencing a sharp decline worldwide and, unfortunately, a continued decrease is expected, mainly due to anthropogenic influence, with negative repercussions for coastal biodiversity. One of these declining seagrasses is Zostera marina L. which is the most widespread in the northern hemisphere (North America, Europe and Asia). One of the most recent observed cases of eelgrass decline occurred in the Special Area of Conservation “Acantilados de Maro - Cerro Gordo” (southern Spain) between 2005 and 2007. These eelgrass beds were probably the deepest ones (5–18 m depth) in Europe and supported a highly diverse associated fauna (Rueda et al., 2009). Different methods have been designed for evaluating ecological integrity or condition status of coastal waters. In general, there is an increasing interest in developing assessment tools for different physicochemical or biological elements of the ecosystems. Taking this into account, what might be the characteristics of a good ecological indicator? In Europe, and within the Water Framework Directive (Directive 2008/56/EC), biological elements are limited to composition, abundance (and biomass) of phytoplankton, other aquatic flora, benthic invertebrate fauna, and fishes. The data used to quantify these biological elements describe distributions/gradients, ratios, biodiversity indices and classification schemes. Environmental science must complement the structural ecosystem properties through an approach towards the ecosystem function and dynamics. In this way, trophic webs constitute probably an appropriate type of measurement of the ecosystem function. Molluscs constitute ca. 25% of the benthos and their dynamics have been shown to reflect the dynamics of the whole community. Therefore, we analyzed the changes in the molluscan taxocoenosis associated with the regression of a Zostera marina bed from the SAC of Acantilados de Maro - Cerro Gordo from 2005 to 2009. We analyzed changes in biotic variables: species richness, abundance, diversity index, biotic indexes and trophic diversity of the molluscan assemblage, and abiotic variables: grain size and percentage of organic matter in sediment. The aim was to check which of these indicators expressed better the environmental changes caused by the regression of the eelgrass bed. Species richness was the best indicator for showing loss of species and the Trophic Index (Danovaro et al., 2004) was the indicator that better expressed the drastic change of the assemblage, with a strong reduction of the trophic groups. Regarding biotic indexes, AMBI, MAMBI and MEDOCC, the absence of eutrophication makes these indicators less accurate to reflect the environmental change caused by the loss of the eelgrass bed. In fact, the best descriptor for this event would be the integrity of seafloor, because the regression of the eelgrass bed changes completely the bottom landscape. The loss of seagrasses and its effects are going to be one of the important topics in future scientific studies due to this continuous declining trend, so tools allowing us to anticipate this threat are becoming essential. In southern Spain, protection of seagrasses is urgently needed for preserving not only the beds but also the diverse communities associated with them

    Detección de anticuerpos contra el virus de lengua azul en ovinos de dos localidades de Junín, Perú

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    The aim of this study was to detect antibodies against bluetongue virus (VLA) in a population of Junín breed sheep bred at 3800 m above the see level in the province of Jauja, Junín and in Blackbelly breed sheep raised at 600 m in the province of Chanchamayo, Junín, Peru. Blood samples (n=306) were collected from Junín sheep, older than 4 months of age, both sexes and from Blackbelly sheep (n=82) older than 4 months, both sexes, from small breeders from four districts (Perene, San Luis de Shauro, San Ramón and Pichanaki) from the province of Chanchamayo, Junín. Antibody detection against the VLA was done by competition ELISA test. All samples (306/306) of the Junín sheep were negative for antibodies against the VLA, while 56.1% (46/82) of the Blackbelly sheep samples had antibodies against the virus. The absence of antibodies against the VLA in sheep raised at 3800 m of altitude indicates that they were not exposed to the VLA, suggesting that high altitude and low temperatures constitute a barrier to the biology of the virus-transmitting vectors, whereas sheep raised at 600 m of altitude were exposed, indicating the presence of the vector or vectors competent for the transmission of bluetongue virus.El objetivo del presente estudio fue detectar anticuerpos contra el virus de lengua azul (VLA) en una población de ovinos de raza Junín criados a 3800 msnm en la provincia de Jauja, Junín, y en ovinos de raza Blackbelly criados a 600 msnm en la provincia de Chanchamayo, Junín, Perú. Se colectaron 306 muestras de sangre de ovinos Junín, mayores a 4 meses de edad, ambos sexos y 82 muestras de ovinos Blackbelly, mayores a 4 meses, ambos sexos, de pequeños criadores de cuatro distritos (Perene, San Luis de Shauro, San Ramón y Pichanaki) de la provincia de Chanchamayo, Junín. La detección de anticuerpos contra el VLA se hizo mediante la prueba de ELISA de competición. El 100% (306/306) de las muestras de los ovinos Junín resultaron negativos a anticuerpos contra el VLA, mientras que 56.1% (46/82) de las muestras de ovinos Blackbelly tuvieron anticuerpos contra el virus. La ausencia de anticuerpos contra el VLA en ovinos criados a 3800 msnm indica que no fueron expuestos al VLA, sugiriendo que la altitud y bajas temperaturas constituyen una barrea para la biología del vector transmisor del virus, en tanto que los ovinos criados a 600 msnm estuvieron expuestos, indicando la presencia del vector o vectores competentes para la transmisión del virus de lengua azul

    Caribbean Corals in Crisis: Record Thermal Stress, Bleaching, and Mortality in 2005

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    BACKGROUND The rising temperature of the world's oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin. METHODOLOGY/PRINCIPAL FINDINGS Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles. CONCLUSIONS/SIGNIFICANCE Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch's Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate.This work was partially supported by salaries from the NOAA Coral Reef Conservation Program to the NOAA Coral Reef Conservation Program authors. NOAA provided funding to Caribbean ReefCheck investigators to undertake surveys of bleaching and mortality. Otherwise, no funding from outside authors' institutions was necessary for the undertaking of this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Identifying non-destructive growth and maturity indexes of Prickly pear (Opuntia albicarpa S. Var. Burrona) and evaluation of freeze-drying conditions

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    Around the world, prickly pear fruits are valued as a source of dietary functional compounds and ingredients for innovative foods. Growth and physicochemical changes of Opuntia albicarpa S. fruits were recorded from 0 to 132 days-after-flowering (DAF) to identify non-destructive maturity-indices. Optimum-ripened fruits were freeze-dried to study physicochemical and functional characteristics of dried and rehydrated pulp. Principal component analysis confirmed growth turned into fruit ripening in DAF 99, and it lasted until DAF 132. Changes in color parameters of the peel correlated with fruit texture and pulp sugar content and taste index (P < 0.01). During freeze-drying, plate temperature had more significant effects than the thickness (P < 0.05). At 30°C, color ΔE between dried and fresh slices augmented, but, texture Δ´s (medium force) between rehydrated and fresh pulp was lower. Color tests could be used to harvest commercially-ripened fruits. Freeze-drying at 30°C improves the rehydrated slices texture regarding thickness maintaining rehydration coefficients.Las tunas son apreciadas en todo el mundo como fuente de compuestos funcionales dietarios e ingredientes para alimentos innovadores. Para identificar índices de maduración no destructivos, se registraron cambios en el crecimiento y en los parámetros fisicoquímicos de frutos de Opuntia albicarpa S. entre los días después de la floración (DAF) 0 al 132. Frutos con maduración óptima fueron liofilizados para evaluar características fisicoquímicas y funcionales de pulpa seca y rehidratada. El análisis de componentes principales confirmo que el crecimiento dio lugar a la maduración en el DAF 99 y ésta prosiguió hasta el DAF 132. Los cambios en parámetros de color en cáscara correlacionaron con la textura del fruto, y en pulpa, con el contenido de azúcares y el índice de sabor (P< 0.01). Durante la liofilización, la temperatura de placa tiene más efectos significativos que el espesor (P≤ 0.05). A 30°C, el ΔE de color entre la pulpa seca y fresca aumentó, pero, el Δ de textura (fuerza media) fue menor entre la rehidratada y la fresca. Se pueden emplear evaluaciones de color para cosechar frutos en su madurez comercial, y liofilizar estos frutos a 30°C mejora la textura sin importar el espesor, manteniendo los coeficientes de rehidratación.This work was supported by the SIMORELOS program of CONACyT

    Considerations and best practices in animal science 16S ribosomal RNA gene sequencing microbiome studies

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    Microbiome studies in animal science using 16S rRNA gene sequencing have become increasingly common in recent years as sequencing costs continue to fall and bioinformatic tools become more powerful and user-friendly. The combination of molecular biology, microbiology, microbial ecology, computer science, and bioinformatics—in addition to the traditional considerations when conducting an animal science study—makes microbiome studies sometimes intimidating due to the intersection of different fields. The objective of this review is to serve as a jumping-off point for those animal scientists less familiar with 16S rRNA gene sequencing and analyses and to bring up common issues and concerns that arise when planning an animal microbiome study from design through analysis. This review includes an overview of 16S rRNA gene sequencing, its advantages, and its limitations; experimental design considerations such as study design, sample size, sample pooling, and sample locations; wet lab considerations such as field handing, microbial cell lysis, low biomass samples, library preparation, and sequencing controls; and computational considerations such as identification of contamination, accounting for uneven sequencing depth, constructing diversity metrics, assigning taxonomy, differential abundance testing, and, finally, data availability. In addition to general considerations, we highlight some special considerations by species and sample type

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

    Synthesis, Biological Evaluation, and Molecular Docking Study of 3-Amino and 3-Hydroxy-seco A Derivatives of α-Amyrin and 3-Epilupeol as Inhibitors of COX-2 Activity and NF-kB Activation

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    In this study, a series of novel 3-seco-A derivatives of the natural triterpenes α-amyrin (1) and 3-epilupeol (2) were synthesized by a one-pot radical scission–oxidation procedure and evaluated in vitro and in vivo for their capacity to inhibit the inflammatory process. For the in vitro studies, the trans-4-hydroxy-l-proline methyl ester derivatives (1f and 2f) were consistently effective in inhibiting NO, IL-6, and TNF-α secretion, as well as inhibition of NF-κB activation, in RAW cells stimulated by LPS. The further in vivo anti-inflammatory study revealed that the trans-4-hydroxy-l-proline methyl ester derivatives (1f and 2f), together with 1g, were the most effective in inhibiting TPA-induced edema. Interestingly, the α-amyrin derivatives were the most potent inhibitors of COX-2, but inhibited COX-1 only to some extent. The hydroxyl derivative (1c) was selective for COX-2 inhibition (66.3 ± 1.1% at 17.5 μM) without affecting the COX-1 isoform and did not present toxicity. Molecular docking studies revealed that these compounds bind with their polar region in the cavity over Arg-120, and their lipophilic part is orientated to the HEM cofactor similarly to the natural substrate arachidonic acid in the catalytic site of COX-2. These results indicated that seco-A ursane derivatives could be considered promising candidates for the future development of selective NF-κB and COX-2 inhibitors.This work was supported by funding from the Consejo Nacional de Ciencia y Tecnología (Grants CB2014-01 240801 and LN294406). A.R.E. acknowledges fellowship no. 253953 from CONACyT. The authors thank Laboratorio Nacional de Estructura de Macromoléculas for the NMR and mass data and Dr. Mario Leyva of Universidad de Sonora and Dr. Zeferino Gómez of Universidad de Colima for the software facilities.Peer reviewe

    Follow-up of loci from the International Genomics of Alzheimer's Disease Project identifies TRIP4 as a novel susceptibility gene

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    To follow-up loci discovered by the International Genomics of Alzheimer's Disease Project, we attempted independent replication of 19 single nucleotide polymorphisms (SNPs) in a large Spanish sample (Fundació ACE data set; 1808 patients and 2564 controls). Our results corroborate association with four SNPs located in the genes INPP5D, MEF2C, ZCWPW1 and FERMT2, respectively. Of these, ZCWPW1 was the only SNP to withstand correction for multiple testing (P=0.000655). Furthermore, we identify TRIP4 (rs74615166) as a novel genome-wide significant locus for Alzheimer's disease risk (odds ratio=1.31; confidence interval 95% (1.19-1.44); P=9.74 × 10 - 9)
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