123 research outputs found
Reorganization of Northern Peri-Gondwanan Terranes at Cambrian–Ordovician Times: Insights from the Detrital Zircon Record of the Ossa-Morena Zone (SW Iberian Massif)
The Ossa-Morena Zone constitutes a fringe Gondwana-related terrane all along the Paleozoic. This continental block has been
classically interpreted as being attached to a portion of the northern Gondwanan margin located close to the West African
Craton. We report here the results of U-Pb dating on detrital zircon grains from 15 metasedimentary rocks collected in two
well-exposed and well-dated Cambrian sections (Córdoba and Zafra) of the Ossa-Morena Zone. The studied samples show a
dominant late Tonian-Ediacaran population peaked at c. 600 Ma. Secondary populations are Rhyacian-early Orosirian and late
Orosirian-Statherian in age, with maxima at c. 2.1 and 1.9 Ga. Minor detrital zircon populations are Mesoarchean-early
Siderian in age, with peaks between c. 3.05 and 2.45 Ga. Most of the studied samples lack a Stenian-early Tonian population,
except for two of them with a minor peak at c. 1 Ga. Our results corroborate previous studies that locate the Ossa-Morena
Zone close to the West African Craton and/or the Tuareg Shield (i.e., in a western position with respect to other Variscan
zones of the Iberian Massif) at the onset of the rifting stage that opened the Rheic Ocean. Nevertheless, the absence of a
significant Stenian-early Tonian population in the Cambrian Ossa-Morena rocks contrasts with the reported results on middle
Ordovician-Lower Devonian rocks of this zone, which systematically contain an important population with a peak at c. 1 Ga.
We relate this change to the latest Ediacaran-early Ordovician paleogeographic/paleotectonic evolution of the Ossa-Morena
Zone, which might have recorded a significant eastward displacement, together with a reorganization of the drainage systems.
Thus, the vanishing stages of the Cadomian orogeny could have translated eastward the Ossa-Morena Zone terrane at latest
Ediacaran-earliest Cambrian time due to change in plate kinematics from subduction to right-lateral shearing. This translation
would have shifted the Ossa-Morena Zone from an Ediacaran location close to the West African Craton to a Cambrian
position close to the Tuareg Shield. Finally, the rift-to-drift transition occurred at late Cambrian-early Ordovician time along
the northern Gondwanan margin would have reorganized the drainage systems, facilitating sediment supply from an eastern
source with abundant Stenian-early Tonian detrital zircon grains, probably the Saharan Metacraton.Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades de la Junta de Andalucia P20_00063
PY20-01387Ministry of Science and Innovation, Spain (MICINN)
Spanish Government PID2020-118822GB-I00
PID2020-119651RB-I0
A Factor Linking Floral Organ Identity and Growth Revealed by Characterization of the Tomato Mutant unfinished flower development (ufd)
Floral organogenesis requires coordinated interactions between genes specifying floral organ identity and those regulating growth and size of developing floral organs. With the aim to isolate regulatory genes linking both developmental processes (i.e., floral organ identity and growth) in the tomato model species, a novel mutant altered in the formation of floral organs was further characterized. Under normal growth conditions, floral organ primordia of mutant plants were correctly initiated, however, they were unable to complete their development impeding the formation of mature and fertile flowers. Thus, the growth of floral buds was blocked at an early stage of development; therefore, we named this mutant as unfinished flower development (ufd). Genetic analysis performed in a segregating population of 543 plants showed that the abnormal phenotype was controlled by a single recessive mutation. Global gene expression analysis confirmed that several MADS-box genes regulating floral identity as well as other genes participating in cell division and different hormonal pathways were affected in their expression patterns in ufd mutant plants. Moreover, ufd mutant inflorescences showed higher hormone contents, particularly ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) and strigol compared to wild type. Such results indicate that UFD may have a key function as positive regulator of the development of floral primordia once they have been initiated in the four floral whorls. This function should be performed by affecting the expression of floral organ identity and growth genes, together with hormonal signaling pathways.This research was supported by the Spanish Ministry of Economy and Competitiveness and the EU European Regional Development Fund (Grants BIO2009-11484 and AGL2015-64991-C3-R-1). We also thank Campus de Excelencia Internacional Agroalimentario (CeiA3) for providing financial support. AO is a recipient of a PhD fellowship from the Ministerio de Ciencia e Innovación of Spain (BIO2009-11484).Peer reviewedPeer Reviewe
Spanish Adaptation of Motivational Climate in Education Scale with University Students
The aim of this study was to provide evidence of the validity and reliability of the dimensionality of the Spanish adaptation of two correlated subscales to assess motivational climate in the university education context: Mastery motivational climate and performance motivational climate. Two different studies with cross-sectional design and different samples of university students were used to accomplish this research (Study 1: 181 students, mean age = 20.83, SD = 1.76; Study 2: 354 students, mean age = 21.84; SD = 1.98). In Study 1, Exploratory Structural Equation Modeling, Confirmatory Factor Analysis (CFA), and reliability analysis of the scale were conducted. In Study 2, CFA, reliability analysis, discriminant validity, temporal stability, factorial invariance across gender, and nomological validity were managed through a regression model measuring the relationships between democratic and autocratic behavior, mastery climate, and performance climate. The final version of the Motivational Climate in Education Scale showed acceptable goodness of fit and values of discriminant validity, reliability, temporal stability, and invariance across gender. According to its nomological validity, democratic behavior was shown to be a statistically significant predictor of mastery climate, and the teacher’s autocratic behavior was shown to be a statistically significant predictor of performance climate. This scale is a valid and reliable instrument to assess mastery climate and performance climate in the Spanish university educational context
Comment on ‘‘Stratigraphy of the Northern Pulo do Lobo Domain, SW Iberia Variscides: A palynological contribution’’ by Zelia Pereira et al. (2018) – Geobios 51, 491–506
The paper by Zelia Pereira et al. (2018) is a valuable input to
better constrain the Devonian palynological record of a number of
siliciclastic formations of the Pulo do Lobo Unit (also known as Pulo
do Lobo Domain or Pulo do Lobo Zone) in SW Iberia. They have
recognized for the first time in the Pulo do Lobo Fm. and in the
imbricated phyllites of the Peramora Me´lange palynomorph
assemblages assigned to the middle Frasnian, as well as new
Devonian palynomorphs in the Ribeira de Limas, Santa Iria and
Horta da Torre formations, and the Alajar Me´ lange. Furthermore,
Ze´ lia Pereira et al. (2018) intend to promote a ‘‘detailed discussion of
the palynological versus geochronological ages by comparing their
biostratigraphic ages with the maximum depositional ages
inferred for the same formations according to detrital zircon
geochronology (Pe´rez-Ca´ ceres et al., 2017; Pereira et al., 2017). The
purpose of their discussion is to question the validity of zircon
geochronological data, which allegedly would be contradictory
with the palynomorph content, and thus not compatible with the
established stratigraphic sequence. In our view, this discussion is
inconsistent due to:
i) the impossibility that primary igneous ages in zircon grains
would have been rejuvenated during Early Carboniferous low-
grade regional metamorphism;
ii) a wrong interpretation of the meaning and implications of
maximal depositional ages derived from the youngest detrital
zircon population
A prescription of methodological guidelines for comparing bio-inspired optimization algorithms
Bio-inspired optimization (including Evolutionary Computation and Swarm Intelligence) is a growing research topic with many competitive bio-inspired algorithms being proposed every year. In such an active area, preparing a successful proposal of a new bio-inspired algorithm is not an easy task. Given the maturity of this research field, proposing a new optimization technique with innovative elements is no longer enough. Apart from the novelty, results reported by the authors should be proven to achieve a significant advance over previous outcomes from the state of the art. Unfortunately, not all new proposals deal with this requirement properly. Some of them fail to select appropriate benchmarks or reference algorithms to compare with. In other cases, the validation process carried out is not defined in a principled way (or is even not done at all). Consequently, the significance of the results presented in such studies cannot be guaranteed. In this work we review several recommendations in the literature and propose methodological guidelines to prepare a successful proposal, taking all these issues into account. We expect these guidelines to be useful not only for authors, but also for reviewers and editors along their assessment of new contributions to the field.This work was supported by grants from the Spanish Ministry of Science (TIN2016-8113-R, TIN2017-89517-P and TIN2017-83132-C2- 2-R) and Universidad Politécnica de Madrid (PINV-18-XEOGHQ-19- 4QTEBP). Eneko Osaba and Javier Del Ser-would also like to thank the Basque Government for its funding support through the ELKARTEK and EMAITEK programs. Javier Del Ser-receives funding support from the Consolidated Research Group MATHMODE (IT1294-19) granted by the Department of Education of the Basque Government
Fungal and Bacterial Biodeterioration of Outdoor Canvas Paintings: The Case of the Cloisters of Quito, Ecuador
The historic center of Quito, Ecuador, was one of the first World Cultural Heritage Sites declared by UNE-ISCO in 1978. here are numerous religious buildings built during the Spanish colonial period reflecting the cultural her- itage in this area. Between them, the cloisters of San Francisco, Santo Domingo, and Santa Clara should be highlighted. The specific problems of conservation of the outdoor canvas paintings are not well known at the moment. The objective of this paper is to achieve a conservation study of the canvas paintings exhibited in these three cloisters of the historic center of Quito in order to identify the microbial agents and the main bioclimatic parameters of deterioration. For this, a study of the state of conservation of five canvas paintings has been carried out, as well as a sampling and identification of the main microorganisms present on the obverse and reverse of the works, employing diverse techniques, traditional and biomolecular ones. An analysis of climatic conditions has also been achieved in the cloister of San Francisco. The results of the study indicate that the exhibition conditions in the cloisters are really problematic for the conservation of paintings. Important biodeteriorating agents have been isolated, including fungi and bacteria species belonging, among others, to the genera Bacillus, Penicillium, Alternaria, Mucor, and Aspergillus. We have also researched its relationship with the deterioration state of the artworks and the exhibi ion conditions in each case, proposing guidelines for the proper conservation of this important World Cultural Heritage
Identification of de novo Mutations of Duchénnè/Becker Muscular Dystrophies in Southern Spain
Background: Duchénnè/Becker muscular dystrophies (DMD/BMD) are X-linked diseases, which are caused by a de novo gene mutation in one-third of affected males. The study objectives were to determine the incidence of DMD/BMD in Andalusia (Spain) and to establish the percentage of affected males in whom a de novo gene mutation was responsible.Methods: Multiplex ligation-dependent probe amplification (MLPA) technology was applied to determine the incidence of DMD/BMD in 84 males with suspicion of the disease and 106 female relatives.Results: Dystrophin gene exon deletion (89.5%) or duplication (10.5%) was detected in 38 of the 84 males by MLPA technology; de novo mutations account for 4 (16.7%) of the 24 mother-son pairs studied.Conclusions: MLPA technology is adequate for the molecular diagnosis of DMD/BMD and establishes whether the mother carries the molecular alteration responsible for the disease, a highly relevant issue for genetic counseling.CGLL has a postdoctoral fellowship from the Plan Propio of the University of Granada
Systematics of detrital zircon U–Pb ages from Cambrian–Lower Devonian rocks of northern Morocco with implications for the northern Gondwanan passive margin
This study was found by the Ministerio de Economia y Competitividad (MINECO) of Spain through the project PANGEATOR (CGL2015-71692) and the Pre-Doctoral scholarship BES-2016-078168. We are indebted to Mike Hall and Brad McDonald for their assistance and technical support on sample preparation and the LA-ICPMS, respectively. The CL imaging was carried out on the Curtin University's Microscopy & Microanalysis Facility, whose instrumentation has been partially funded by the University, State and Commonwealth Governments, and the Scanning Electron Microscope (SEM) Facility at the University of Edinburgh. Analysis in the SHRIMP and GeoHistory Facilities, JdLC, Curtin University were enabled by AuScope (auscope.org.au) and the Australian Government via the National Collaborative Research Infrastructure Strategy (NCRIS) and an Australian Geophysical Observing System grant provided to AuScope Pty Ltd. by the AQ44 Australian Education Investment Fund program, respectively. The NPII multi-collector was obtained via funding from the Australian Research Council LIEF program (LE150100013). The SIMS analyses were performed at the NERC Ion Microprobe Facility of the University of Edinburgh (UK). Comments from two anonymous reviewers and editorial handling by Prof. Victoria Pease are acknowledged. Funding for open access charge: YUniversidad de Granada / CBUA.The systematic acquisition of U–Pb geochronological data from detrital zircon grains has become an essential
tool in tectonic studies focused on reconstructing the pre–Variscan geography of the northern Gondwanan
passive margin. New detrital zircon ages for 16 samples from the Cambrian–Lower Devonian succession of the
Moroccan Mesetas (northern Morocco) are reported here. The results, combined with previously published data,
reassert the strong West African Craton affinity of the Paleozoic sedimentary rocks, characterized by dominant
Cadomian/Pan–African (c. 850–540 Ma) and Eburnean (c. 2.2–1.9 Ga) detrital zircon populations and a minor
Leonian/Liberian (c. 2.5 Ga) population. Primary sources of these zircon grains are well established as the West
African Craton located just to the south, but also in the Precambrian basement that locally crops out in the
Moroccan Mesetas themselves. During the Cambrian–Early Ordovician, erosion preferentially dismantled
Cadomian (c. 590–540 Ma) arc–derived rocks of the Gondwanan continental margin, while later, the slightly
older Pan–African (c. 650–600 Ma) basement became the main sediment source. In the studied samples, irregularly
present minor detrital zircon populations suggest additional sediment provenance from secondary sources
such as: (i) remote northeastern African cratons (e.g., Saharan Metacraton and/or Arabian–Nubian Shield) that
likely could have provided the c. 1.1–0.9 Ga and, possibly, the c. 1.9–1.7 Ga zircon grains, and (ii) rift–related
Cambrian–Early Ordovician volcanic centers in the Moroccan Mesetas that supplied heterogeneously distributed
– although locally dominant in small areas – sedimentary detritus before rift abortion and burial underneath the
overlying passive margin sedimentary succession.Ministerio de Economia y Competitividad (MINECO) of Spain through the project PANGEATOR CGL2015-71692Scanning Electron Microscope (SEM) Facility at the University of EdinburghAustralian Geophysical Observing System grant by AQ44 Australian Education Investment Fund programAustralian Research Council LE150100013Universidad de Granada / CBUA
BES-2016-07816
Syn-collisional detrital zircon source evolution in the northern Moroccan Variscides
Ministerio de EconomÃa y Competitividad (MINECO) of Spain through the project PANGEATOR (CGL2015-71692) and the Pre-doctoral scholarship BES-2016-078168.U–Pb dating and Hf isotopic analyses of detrital zircon grains from Cambrian-Devonian strata in the Moroccan
Mesetas were undertaken in order to constrain its Paleozoic paleogeographic evolution. In this work, we analyzed
12 LateDevonian-Late Carboniferous samples of syn-collisional detrital rocks fromtheWestern and Eastern
Moroccan Mesetas. All our samples present significant Ediacaran (ca. 620 Ma) and Rhyacian (ca. 2.1 Ga) detrital
zircon populations, suggesting that theWest African Craton remained themain source of sediments for northern
Morocco at least until the Late Carboniferous. Locally, a Stenian-Tonian (ca. 1.0 Ga) detrital zircon population is
also present, probably fed from intermittent and distant source areas located in NE Africa (e.g. Sahara
Metacraton). The collisional evolution started with the approach of an Avalonian promontory to the northern
Gondwana continental margin (latest Devonian - earliest Carboniferous), after the closure of the Rheic Ocean.
This process entailed the former subduction of the Rheic oceanic lithosphere underneath the Avalonian continental
terrane and the formation of a magmatic arc in the upper plate. In this scenario, the first syn-collisional sediments
(Tournaisian; Tiflet and Debdou-Mekkam areas) are characterized by a Devonian detrital zircon
population (ca. 370 Ma), presumably derived from the magmatic arc, and an increasing number of
Mesoproterozoic dates, putatively also sourced from the continental crust of the Avalonian terrane. After the initial
collision, only the Visean samples located in areas close to the exotic terrane (e.g. Ben Slimane area) displayed
a minor Avalonian component. Finally, the Late Carboniferous samples from the Jerada area recorded an important
Middle Carboniferous (ca. 330 Ma) detrital zircon population, probably sourced from Variscan granitoids
emplaced in the Eastern Moroccan Meseta and attesting to crustal thickening and subsequent thermal maturation
of the Gondwana continental crust in this area.Ministerio de EconomÃa y Competitividad (MINECO) of Spain PANGEATOR (CGL2015-71692)Pre-doctoral scholarship BES-2016-07816
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