228 research outputs found
Cenogramas, análisis bioclimático y muestreo en faunas de mamíferos: implicaciones para la aplicación de métodos de análisis paleoecológico
In this work we analyzed the problems derived from the potential species loss associated to the taphonomic processes occurring in fossil sites. We seek to resolve the possible utility of cenograms and bioclimatic analysis as methodologies applicable in Paleoecology. Supposedly, if species are deleted in a community, significant changes in its structure might appear, which would make these paleoecological techniques dysfunctional. The analysis has been carried out with the data of two modern mammalian communities, Barrow (Alaska) and Jaipur (India), on which we have deleted species randomly. Our
results have allowed us to conclude that these methodologies are useful in Paleoecology, since they are functional with a satisfactory level of confidence, as long as the species loss is not excessively elevated (for communities with 20-40% of the original species).En este trabajo hemos analizado la problemática derivada de la posible pérdida de especies asociada a los procesos tafonómicos que se dan en los yacimientos de fósiles, para determinar la posible utilidad de los cenogramas y el análisis bioclimático como metodologías aplicables en Paleoecología. Podría suponerse que si eliminamos especies en una comunidad se podrían producir cambios significativos en su estructura que convertirían en no funcionales a estas metodologías. El análisis se ha llevado a cabo con los datos de dos comunidades de mamíferos actuales, Barrow (Alaska) y Jaipur (India), de las que hemos eliminado progresivamente especies de forma aleatoria. Los resultados obtenidos nos han permitido concluir que tanto los cenogramas como el análisis bioclimático son útiles en Paleoecología, ya que son funcionales con un nivel de confianza adecuado, siempre y cuando la pérdida de especies
no sea excesivamente elevada (en comunidades con un 20-40% de las especies originales).La presente investigación ha sido
parcialmente financiada por los proyectos PR1/06-14470-B (UCM) y CGL2006-01773/BTE (MEC) y por una ayuda de la Universidad Complutense de Madrid y la Comunidad Autónoma de Madrid al Grupo de Investigación UCM-CAM 910607 sobre Evolución de Mamíferos y Paleoambientes Continentales Cenozoicos, dirigido por Marián Álvarez Sierra. Asimismo, el
mencionado grupo de investigación ha financiado la presentación de estos resultados en las XXII Jornadas de la Sociedad Española de Paleontología. M.H.F. disfruta de un contrato UCM del Programa «Ramón y Cajal» del Ministerio de Educación y Ciencia.Peer reviewe
Mortalidad excepcional en los cricétidos (Rodentia) del Mioceno medio de Somosaguas (Pozuelo de Alarcón, Madrid)
Altres ajuts: Generalitat de Catalunya (programa CERCA).En este estudio se analizó el espectro de desgaste dental de los molares, superiores e inferiores, de individuos de las dos especies de roedores más abundantes registradas en el yacimiento de Somosaguas Sur: Megacricetodon collongensis (Mein, 1958) y Democricetodon larteti (Schaub, 1925). Los resultados muestran gran abundancia de molares poco desgastados en ambas especies, lo que indica la existencia de una mortalidad fuertemente sesgada hacia los individuos juveniles. Este modelo de mortalidad refleja un suceso catastrófico de larga duración y se asocia a periodos de sequía prolongados que produjeron la muerte temprana de los individuos durante generaciones. Esto es coherente con los datos obtenidos para los macromamíferos de Somosaguas donde también existe una mortalidad preferencial de los individuos juveniles asociada a eventos de gran aridez. A pesar de que todos los molares mostraron el mismo patrón de mortalidad preferencial en individuos jóvenes, ambas especies presentaron diferentes niveles de desgaste entre los distintos molares, lo cual sugiere que el proceso de masticación pudo ser distinto entre ambas especies o que el inicio del desgaste de los molares anteriores pudo iniciarse durante la lactancia. Finalmente, el desgaste diferencial observado entre los M1 de M. collongensis y D. larteti podría deberse a la distinta morfología de las cúspides y valles de sus molares, lo que provocaría que el desgaste no se produjese de la misma manera en las dos especies, o a ligeras diferencias dietarias.In this work we studied the wear degree of the superior and lower molars of the two most abundant rodent species from the South Somosaguas fossil site: Megacricetodon collongensis (MEIN, 1958) and Democricetodon larteti (SCHAUB, 1925). The results show a great abundance of elements with scarce tooth wear in both species, which indicates the existence of a high mortality of young individuals. This mortality model shows an enduring catastrophic event associated to long periods of aridity that produced juvenile mortality along generations. This tendency of mortality fits in the patterns obtained from other works from Somosaguas where the existence of high rates of deaths of young individuals is associated with events of high aridity. D. larteti and M. collongensis have different patterns of wear degree along their dental rows, which could indicate that the mastication process was different in both species or maybe that the tooth wear started earlier. Finally, the differences in wear degree observed in the M1 of M. collongensis and D. larteti can be explained by the different morphology of the peaks and valleys of the molars, which cause a faster wear of the first molar of D. larteti than in those of M. collongensis; or by light dietary differences
Ecomorphological characterization of murines and non-arvicoline cricetids (Rodentia) from south-western Europe since the latest Middle Miocene to the Mio-Pliocene boundary (MN 7/8-MN13)
SUBVENCIÓ: Universidad Complutense de Madrid: BOUC UCM 17-5-2016 (CT27 / 16-CT28 / 16)Rodents are the most speciose group of mammals and display a great ecological diversity. Despite the greater amount of ecomorphological information compiled for extant rodent species, studies usually lack of morphological data on dentition, which has led to difficulty in directly utilizing existing ecomorphological data of extant rodents for paleoecological reconstruction because teeth are the most common or often the only micromammal fossils. Here, we infer the environmental ranges of extinct rodent genera by extracting habitat information from extant relatives and linking it to extinct taxa based on the phenogram of the cluster analysis, in which variables are derived from the principal component analysis on outline shape of the upper first molars. This phenotypic ''bracketing'' approach is particularly useful in the study of the fossil record of small mammals, which is mostly represented by isolated teeth. As a case study, we utilize extinct genera of murines and non-arvicoline cricetids, ranging from the Iberoccitanian latest middle Miocene to the Mio-Pliocene boundary, and compare our results thoroughly with previous paleoecological reconstructions inferred by diferent methods. The resultant phenogram shows a predominance of ubiquitous genera among the Miocene taxa, and the presence of a few forest specialists in the two rodent groups (Murinae and Cricetidae), along with the absence of open environment specialists in either group of rodents. This appears to be related to the absence of enduring grassland biomes in the Iberian Peninsula during the late Miocene. High consistency between our result and previous studies suggests that this phenotypic ''bracketing'' approach is a very useful tool
Eligibility criteria for Menopausal Hormone Therapy (MHT): a position statement from a consortium of scientific societies for the use of MHT in women with medical conditions. MHT Eligibility Criteria Group
This project aims to develop eligibility criteria for menopausal hormone therapy (MHT). The tool should be
similar to those already established for contraception A consortium of scientific societies coordinated by the
Spanish Menopause Society met to formulate recommendations for the use of MHT by women with medical conditions based on the best available evidence. The project was developed in two phases. As a first step, we
conducted 14 systematic reviews and 32 metanalyses on the safety of MHT (in nine areas: age, time of menopause
onset, treatment duration, women with thrombotic risk, women with a personal history of cardiovascular
disease, women with metabolic syndrome, women with gastrointestinal diseases, survivors of breast cancer or of
other cancers, and women who smoke) and on the most relevant pharmacological interactions with MHT. These
systematic reviews and metanalyses helped inform a structured process in which a panel of experts defined the
eligibility criteria according to a specific framework, which facilitated the discussion and development process.
To unify the proposal, the following eligibility criteria have been defined in accordance with the WHO international
nomenclature for the different alternatives for MHT (category 1, no restriction on the use of MHT;
category 2, the benefits outweigh the risks; category 3, the risks generally outweigh the benefits; category 4,
MHT should not be used). Quality was classified as high, moderate, low or very low, based on several factors
(including risk of bias, inaccuracy, inconsistency, lack of directionality and publication bias). When no direct
evidence was identified, but plausibility, clinical experience or indirect evidence were available, "Expert opinion"
was categorized. For the first time, a set of eligibility criteria, based on clinical evidence and developed according
to the most rigorous methodological tools, has been defined. This will provide health professionals with a
powerful decision-making tool that can be used to manage menopausal symptoms
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Plio-Pleistocene climatic change had a major impact on the assembly and disassembly processes of Iberian rodent communities
Comprehension of changes in community composition through multiple spatio-temporal scales is a prime challenge in ecology and palaeobiology. However, assembly, structuring and disassembly of biotic metacommunities in deep-time is insufficiently known. To address this, we used the extensively sampled Iberian Plio-Pleistocene fossil record of rodent faunas as our model system to explore how global climatic events may alter metacommunity structure. Through factor analysis, we found five sets of genera, called faunal components, which co-vary in proportional diversity over time. These faunal components had different spatio-temporal distributions throughout the Plio-Pleistocene, resulting in non-random changes in species assemblages, particularly in response to the development of the Pleistocene glaciations. Three successive metacommunities with distinctive taxonomic structures were identified as a consequence of the differential responses of their members to global climatic change: (1) Ruscinian subtropical faunas (5.3–3.4 Ma) dominated by a faunal component that can be considered as a Miocene legacy; (2) transition faunas during the Villafranchian–Biharian (3.4–0.8 Ma) with a mixture of different faunal components; and (3) final dominance of the temperate Toringian faunas (0.8–0.01 Ma) that would lead to the modern Iberian assemblage. The influence of the cooling global temperature drove the reorganisation of these rodent metacommunities. Selective extinction processes due to this large-scale environmental disturbance progressively eliminated the subtropical specialist species from the early Pliocene metacommunity. This disassembly process was accompanied by the organisation of a diversified metacommunity with an increased importance of biome generalist species, and finally followed by the assembly during the middle–late Pleistocene of a new set of species specialised in the novel environments developed as a consequence of the glaciations
Psychometric characteristics of the Spanish version of instruments to measure neck pain disability
Background: The NDI, COM and NPQ are evaluation instruments for disability due to NP. There was no Spanish version of NDI or COM for which psychometric characteristics were known. The objectives of this study were to translate and culturally adapt the Spanish version of the Neck Disability Index Questionnaire (NDI), and the Core Outcome Measure (COM), to validate its use in Spanish speaking patients with non-specific neck pain (NP), and to compare their psychometric characteristics with those of the Spanish version of the Northwick Pain Questionnaire (NPQ).
Methods: Translation/re-translation of the English versions of the NDI and the COM was done blindly and independently by a multidisciplinary team. The study was done in 9 primary care Centers and 12 specialty services from 9 regions in Spain, with 221 acute, subacute and chronic patients who visited their physician for NP: 54 in the pilot phase and 167 in the validation phase. Neck pain (VAS), referred pain (VAS), disability (NDI, COM and NPQ), catastrophizing (CSQ) and quality of life (SF-12) were measured on their first visit and 14 days later. Patients' self-assessment was used as the external criterion for pain and disability. In the pilot phase, patients' understanding of each item in the NDI and COM was assessed, and on day 1 test-retest reliability was estimated by giving a second NDI and COM in which the name of the questionnaires and the order of the items had been changed.
Results: Comprehensibility of NDI and COM were good. Minutes needed to fill out the questionnaires [median, (P25, P75)]: NDI. 4 (2.2, 10.0), COM: 2.1 (1.0, 4.9). Reliability: [ICC, (95%CI)]: NDI: 0.88 (0.80, 0.93). COM: 0.85 (0.75,0.91). Sensitivity to change: Effect size for patients having worsened, not changed and improved between days 1 and 15, according to the external criterion for disability: NDI: -0.24, 0.15, 0.66; NPQ: -0.14, 0.06, 0.67; COM: 0.05, 0.19, 0.92. Validity: Results of NDI, NPQ and COM were consistent with the external criterion for disability, whereas only those from NDI were consistent with the one for pain. Correlations with VAS, CSQ and SF-12 were similar for NDI and NPQ (absolute values between 0.36 and 0.50 on day 1, between 0.38 and 0.70 on day 15), and slightly lower for COM (between 0.36 and 0.48 on day 1, and between 0.33 and 0.61 on day 15). Correlation between NDI and NPQ: r = 0.84 on day 1, r = 0.91 on day 15. Correlation between COM and NPQ: r = 0.63 on day 1, r = 0.71 on day 15.
Conclusion: Although most psychometric characteristics of NDI, NPQ and COM are similar, those from the latter one are worse and its use may lead to patients' evolution seeming more positive than it actually is. NDI seems to be the best instrument for measuring NP-related disability, since its results are the most consistent with patient's assessment of their own clinical status and evolution. It takes two more minutes to answer the NDI than to answer the COM, but it can be reliably filled out by the patient without assistance
Traditional Mapuche ecological knowledge in Patagonia, Argentina: fishes and other living beings inhabiting continental waters, as a reflection of processes of change
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V
Geographic patterns of tree dispersal modes in Amazonia and their ecological correlates
Aim: To investigate the geographic patterns and ecological correlates in the geographic distribution of the most common tree dispersal modes in Amazonia (endozoochory, synzoochory, anemochory and hydrochory). We examined if the proportional abundance of these dispersal modes could be explained by the availability of dispersal agents (disperser-availability hypothesis) and/or the availability of resources for constructing zoochorous fruits (resource-availability hypothesis).
Time period: Tree-inventory plots established between 1934 and 2019.
Major taxa studied: Trees with a diameter at breast height (DBH) ≥ 9.55 cm.
Location: Amazonia, here defined as the lowland rain forests of the Amazon River basin and the Guiana Shield.
Methods: We assigned dispersal modes to a total of 5433 species and morphospecies within 1877 tree-inventory plots across terra-firme, seasonally flooded, and permanently flooded forests. We investigated geographic patterns in the proportional abundance of dispersal modes. We performed an abundance-weighted mean pairwise distance (MPD) test and fit generalized linear models (GLMs) to explain the geographic distribution of dispersal modes.
Results: Anemochory was significantly, positively associated with mean annual wind speed, and hydrochory was significantly higher in flooded forests. Dispersal modes did not consistently show significant associations with the availability of resources for constructing zoochorous fruits. A lower dissimilarity in dispersal modes, resulting from a higher dominance of endozoochory, occurred in terra-firme forests (excluding podzols) compared to flooded forests.
Main conclusions: The disperser-availability hypothesis was well supported for abiotic dispersal modes (anemochory and hydrochory). The availability of resources for constructing zoochorous fruits seems an unlikely explanation for the distribution of dispersal modes in Amazonia. The association between frugivores and the proportional abundance of zoochory requires further research, as tree recruitment not only depends on dispersal vectors but also on conditions that favour or limit seedling recruitment across forest types
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