1,667 research outputs found
Identifying past social-ecological thresholds to understand long-term temporal dynamics in Spain
A thorough understanding of long-term temporal social-ecological dynamics at the national scale helps to explain the current condition of a country’s ecosystems and to support environmental policies to tackle future sustainability challenges. We aimed to develop a methodological approach to understand past long-term (1960-2010) social-ecological dynamics in Spain. First, we developed a methodical framework that allowed us to explore complex social-ecological dynamics among biodiversity, ecosystem services, human well-being, drivers of change, and institutional responses. Second, we compiled 21 long-term, national-scale indicators and analyzed their temporal relationships through a redundancy analysis. Third, we used a Bayesian change point analysis to detect evidence of past social-ecological thresholds and historical time periods. Our results revealed that Spain has passed through four socialecological thresholds that define five different time periods of nature and society relationships. Finally, we discussed how the proposed methodological approach helps to reinterpret national-level ecosystem indicators through a new conceptual lens to develop a more systems-based way of understanding long-term social-ecological patterns and dynamicsThis work was supported by the Biodiversity Foundation (http://www.fundacion-biodiversidad.es/) of the Spanish Ministry of Agriculture, Food and Environment. Partial
financial support was also provided by the Ministry of Economy and Competitiveness of Spain (project CGL2014-53782-P: ECOGRADIENTES). The Spanish National Institute for
Agriculture and Food Research and Technology (INIA) funded Marina García-Llorente as part of the European Social Fund. Blanca González García-Mon participated in this article as a “la
Caixa” Banking Foundation scholar. The funders had no role in the study design, data collection and analysis, preparation of the report, or the decision to submit the study for publicatio
The Intergalactic Stellar Population from Mergers of Elliptical Galaxies with Dark Matter halos
We present simulations of dry-merger encounters between pairs of elliptical
galaxies with dark matter halos. The aim of these simulations is to study the
intergalactic stellar populations produced in both parabolic and hyperbolic
encounters. We model progenitor galaxies with total-to-luminous mass ratios
M_T/M_L 3 and 11. The initial mass of the colliding galaxies are chosen so that
M_1/M_2 and 10. The model galaxies are populated by particles representing
stars, as in Stanghellini et al. (2006), and dark matter. Merger remnants
resulting from these encounters display a population of unbounded particles,
both dark and luminous. The number of particles becoming unbounded depends on
orbital configuration, with hyperbolic encounters producing a larger luminous
intracluster population than parabolic encounters. Furthermore, in simulations
with identical orbital parameters, a lower M_T/M_L of the colliding galaxies
produces a larger fraction of unbounded luminous particles. For each modeled
collision, the fraction of unbounded to initial stellar mass is the same in all
mass-bins considered, similarly to what we found previously by modeling
encounters of galaxies without dark halos. The fraction of intergalactic to
total luminosity resulting from our simulations is ~ 4% and ~ 6% for
dark-to-bright mass rations of 10 and 2 respectively. These unbounded-to-total
luminous fractions are down from 17 % that we had previously found in the case
of no dark halos. Our results are in broad agreement with intergalactic light
observed in groups of galaxies, while the results of our previous models
without dark halos better encompass observed intracluster populations. We
suggest a possible formation scenario of intergalactic stars.Comment: Accepted for publication in Ap
In vivo extracellular matrix protein expression by human periodontal ligament after stimulation with orthodontic force
It is well known that the orthodontic force applied to teeth generates a series of events that remodel the periodontal ligament (PDL). Extracellular matrix proteins (ECM) are described as molecular regulators of these events. However, the exact contribution of these proteins in human PDL modeling by orthodontic force application in vivo is not known. The aim of this present study was to evaluate the protein expression of fibronectin, laminin and vitronectin by human PDL from teeth on which orthodontic force was applied. Twenty healthy individuals were included in the study. PDL was obtained from teeth after a 3-week treatment with orthodontic force. PDL-protein samples were separated on 7.5% SDS-PAGE Western blot analysis with specific monoclonal antibodies for fibronectin, laminin and vitronectin. Bands were visualized with an enhanced chemiluminescence detection system and densitometric. Scanning of bands was carried out to compare differences in protein expression. A significant increment in fibronectin (13.9%), laminin (16.5%) and vitronectin (14.2%) expression was found in PDL from teeth treated with orthodontic force for 3 weeks in comparison with teeth in the control group. Our results support the concept that molecular changes take place by application of orthodontic forces to the PDL. Over expression of these proteins suggests that extracellular matrix (ECM) remodeling could be generated in response to mechanical stress.Keywords: Extracellular matrix proteins, periodontal ligament, orthodontic forceAfrican Journal of Biotechnology Vol. 9(34), pp. 5599-5604, 23 August, 201
Expansión de la mancha urbana de la Ciudad de Chihuahua 2000-2012
En el presente trabajo se pretende dar a conocer el acelerado crecimiento de la mancha urbana de la ciudad de Chihuahua que se ha generado en tan solo diez años, mediante los Sistemas de Información Geográfica lo que hace una investigación novedosa e interesante, con estos sistemas podemos ver que, si bien la ciudad ha tenido un crecimiento en su espacio, económico y social no se ha dado un desarrollo equilibrado sobre su territorio. Por lo que el objetivo de esta investigación es conocer las acciones políticas, sociales, ambientales y económicas, que produjeron la expansión de la mancha urbana en sus diferentes puntos cardinales de la Ciudad en los últimos 10 años, representados con los SIG. Generado problemáticas sobre todo en el tema de los asentamientos humanos en espacios carentes de características viables para una buena calidad de vida, dejando consecuencias en la estructura de la ciudad, tanto física como social, puesto que no se dio una adecuada planeación para el crecimiento de la mancha urbana
Forest productivity in southwestern Europe controlled by coupled North Atlantic and Atlantic Multidecadal Oscillations
The North Atlantic Oscillation (NAO) depicts annual and decadal oscillatory modes ofvariability responsible for dry spells over the European continent. The NAO therefore holds agreat potential to evaluate the role, as carbon sinks, of water-limited forests under climatechange. However, uncertainties related to inconsistent responses of long-term forestproductivity to NAO have so far hampered firm conclusions on its impacts. We hypothesizethat, in part, such inconsistencies might have their origin in periodical sea surfacetemperature anomalies in the Atlantic Ocean (i.e., Atlantic Multidecadal Oscillation, AMO).Here we show strong empirical evidence in support of this hypothesis using 120 years ofperiodical inventory data from Iberian pine forests. Our results point to AMO+ NAO+ andAMO−NAO− phases as being critical for forest productivity, likely due to decreased winterwater balance and abnormally low winter temperatures, respectively. Our findings could beessential for the evaluation of ecosystem functioning vulnerabilities associated with increasedclimatic anomalies under unprecedented warming conditions in the Mediterranean
Investigating mutations in the genes GDF9 and BMP15 in Pelibuey sheep through the amplification-refractory mutation system with tetra-primers
Single Nucleotide Polymorphisms (SNP) or mutations are variations with a broad distribution in the genome and, as part of genetic studies, SNP allow the identification of allelic variants related to characteristics of economic importance in sheep production. However, the identification of SNP and their genotypes through sequencing is expensive, as it requires specialized materials and equipment. The objective of this study was to identify polymorphisms and their genotypes in the growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) genes in Pelibuey sheep using the tetra-primer amplification-refractory mutation system through polymerase chain reaction (T-ARMS-PCR). DNA extraction and amplification of BMP15 and GDF9 were conducted from blood samples contained in WhatmanTM FTATM cards from 60 multiparous Pelibuey ewes with reproductive records. The T-ARMS-PCR methodology allowed the identification of wild-type genotypes and mutated homozygous genotypes in polymorphisms G4 and G6 of GDF9, whereas mutations in the BMP15 gene were not found. These results were confirmed by sequencing. In conclusion, the T-ARMS-PCR methodology allowed the identification of mutated and wild-type genotypes in SNP G4 and G6 of GDF9, although no mutations were found in BMP15 in Pelibuey sheep. This technique was found to be reliable, rapid, and easily applied to identify polymorphic genotypes
Recent advances in gastrointestinal stromal tumors: Where are we going?
Tumores del estroma gastrointestinal; Inhibidores de la tirosina cinasa; LaparoscopiaGastrointestinal stromal tumors; Tyrosine kinase inhibitors; LaparoscopyTumors de l'estroma gastrointestinal; Inhibidors de la tirosina cinasa; LaparoscòpiaLos tumores del estroma gastrointestinal (GIST) suponen el 1-2% de los tumores digestivos, siendo su localización más frecuente el estómago (55-60%) y el intestino delgado (30%). Los avances más importantes sucedidos en los últimos años se centran en cuatro áreas: biología molecular, abordaje quirúrgico laparoscópico, manejo técnico del GIST en localizaciones inusuales y tratamiento e integración de la cirugía en el manejo del GIST avanzado. Los avances en el conocimiento de la biología molecular del GIST han dado lugar a la progresiva identificación de nueva mutaciones oncogénicas que hacen del concepto wild type obsoleto. Estos avances han permitido el desarrollo de dos nuevos fármacos, avapritinib y ripretinib, lo que permite el tratamiento de pacientes con mutaciones resistentes a las tres líneas terapéuticas clásicas. El tratamiento quirúrgico del GIST se rige por unos principios técnicos bien establecidos que el abordaje laparoscópico debe cumplir, abordaje que queda limitado por dos factores clave: localización y tamaño. El GIST de localización infrecuente (esófago, duodeno o recto, o extradigestivo) supone un reto terapéutico. Estos pacientes deben ser manejados en un contexto multidisciplinario. La cirugía queda integrada en el manejo del GIST avanzado, considerándose como adyuvante a los inhibidores de la tirosina cinasa.Gastrointestinal Stromal Sarcomas (GIST) are mesenchymal neoplasms whose incidence accounts for 1-2% of digestive tumors, being located in the stomach (55-60%) and small intestine (30%). The advances in its knowledge and management succeeded in the last years have being spectacular. This review aims to summarize the most important of them for surgeons. We identified four areas of interest: molecular oncology, laparoscopic approach, management of GIST located at unusual locations, and management of advanced GIST. Advances in the field of molecular oncology lead to the discovery of new oncogenic mutations making the term Wil Type GIST obsolete. Moreover, these advances allow for the development of 2 new drugs: Avapritinib and Ripretinib, that added to the previous 3 commercially available drugs (imatinib, sunitinib and regorafenib) make possible the management of GIST with resistant mutations. The principles of the surgical management of primary GIST are well stablished which laparoscopic approach must accomplish. This approach is limited by 2 main factors: location and size. The diagnosis of GIST in unusual locations as esophagus, duodenum, rectum of out of the gastrointestinal tract (EGIST), implies an extraordinary therapeutic challenge, being imperative to manage them by surgeons and oncologist among others in the setting of a multidisciplinary team. The management of advanced/metastatic GIST has changed in a revolutionary fashion because surgery is now part of its treatment as adjuvant to tyrosine kinase inhibitors
Galaxy clusters and groups in the ALHAMBRA Survey
We present a catalogue of 348 galaxy clusters and groups with
selected in the 2.78 ALHAMBRA Survey. The high precision of our
photometric redshifts, close to , and the wide spread of the seven
ALHAMBRA pointings ensure that this catalogue has better mass sensitivity and
is less affected by cosmic variance than comparable samples.
The detection has been carried out with the Bayesian Cluster Finder (BCF),
whose performance has been checked in ALHAMBRA-like light-cone mock catalogues.
Great care has been taken to ensure that the observable properties of the mocks
photometry accurately correspond to those of real catalogues. From our
simulations, we expect to detect galaxy clusters and groups with both
completeness and purity down to dark matter halo masses of
for . Cluster redshifts are
expected to be recovered with precision for . We also expect
to measure cluster masses with
precision down to , masses which are
smaller than those reached by similar work.
We have compared these detections with previous optical, spectroscopic and
X-rays work, finding an excellent agreement with the rates reported from the
simulations. We have also explored the overall properties of these detections
such as the presence of a colour-magnitude relation, the evolution of the
photometric blue fraction and the clustering of these sources in the different
ALHAMBRA fields. Despite the small numbers, we observe tentative evidence that,
for a fixed stellar mass, the environment is playing a crucial role at lower
redshifts (z0.5).Comment: Accepted for publication in MNRAS. Catalogues and figures available
online and under the following link:
http://bascaso.net46.net/ALHAMBRA_clusters.htm
Gene signatures of early response to anti-TNF drugs in pediatric inflammatory bowel disease
T. Around a 20–30% of inflammatory bowel disease (IBD) patients are diagnosed before they are 18 years old. Anti-TNF drugs can induce and maintain remission in IBD, however, up to 30% of patients do not respond. The aim of the work was to identify markers that would predict an early response to anti-TNF drugs in pediatric patients with IBD. The study population included 43 patients aged <18 years with IBD who started treatment with infliximab or adalimumab. Patients were classified into primary responders (n = 27) and non-responders to anti-TNF therapy (n = 6). Response to treatment could not be analyzed in 10 patients. Response was defined as a decrease in over 15 points in the disease activity indexes from week 0 to week 10 of infliximab treatment or from week 0 to week 26 of adalimumab treatment. The expression profiles of nine genes in total RNA isolated from the whole-blood of pediatric IBD patients taken before biologic administration and after 2 weeks were analyzed using qPCR and the 2−∆∆Ct method. Before initiation and after 2 weeks of treatment the expression of SMAD7 was decreased in patients who were considered as non-responders (p value < 0.05). Changes in expression were also observed for TLR2 at T0 and T2, although that did not reach the level of statistical significance. In addition, the expression of DEFA5 decreased 1.75-fold during the first 2 weeks of anti-TNF treatment in responders, whereas no changes were observed in non-responders. Expression of the SMAD7 gene is a pharmacogenomic biomarker of early response to anti-TNF agents in pediatric IBD. TLR2 and DEFA5 need to be validated in larger studies.This work was funded by Instituto de Salud Carlos III (grants numbers PI16/00559 and PI19/00792), Consejería de Educación y Deporte de la Comunidad de Madrid (grant number PEJ16/MED/AI-1260), and by the Gregorio Marañón Health Research Institute (grant number PRE-2018-2), The study was cofunded by ERDF Funds (FEDER) from the European Commission, “A way of making Europe
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