66 research outputs found
Testing the usefulness of the surface collecting method in a vertebrate microfossil site from the barremian of Spain (Los Menires, Mirambel formation)
Surface collecting is the first and sometimes the only type of sampling carried out in many fossiliferous localities, including vertebrate microfossil assemblages. Nevertheless, it is rare to test how representative these surface-collected samples are of the palaeobiocoenosis. A first approach to the palaeontological analysis of Los Menires, a Barremian vertebrate microfossil assemblage, is here performed while testing the usefulness of the surface collection method. New fossil material obtained by surface collection is described, and the resulting data are compared with those obtained by screen-washing. The fossil assemblage of Los Menires is dominated by parautochthonous remains of freshwater aquatic and semiaquatic organisms—i.e., charophytes, ostracods, bivalves, gastropods, testudinatans, crocodylomorphs, lissamphibians, and osteichthyans—although parautochthonous remains of terrestrial vertebrates—i.e., dinosaurs, lacertilians, and mammaliforms—are also present. The accumulation of vertebrate hard parts in Los Menires took place in a low-energy, shallow-water, depositional environment within the alluvial-lacustrine system represented by the Mirambel Formation. Sampling test results indicate that surface collection is effective in recognizing the main fossil groups present in an assemblage. Yet, it is not suitable for capturing delicate and tiny fossils nor for recognizing the abundance of eggshells. In contrast, it can generate an overrepresentation of other hard components such as coprolites or ornithopod teeth
A new primitive Neornithischian dinosaur from the Jurassic of Patagonia with gut contents
We describe a new species of an ornithischian dinosaur, Isaberrysaura mollensis gen. et sp. nov. The specimen, consisting in an almost complete skull and incomplete postcranium was collected from the marine-deltaic deposits of the Los Molles Formation (Toarcian-Bajocian), being the first reported dinosaur for this unit, one of the oldest from Neuquén Basin, and the first neornithischian dinosaur known from the Jurassic of South America. Despite showing a general stegosaurian appearance, the extensive phylogenetic analysis carried out depicts Isaberrysaura mollensis gen. et sp. nov. as a basal ornithopod, suggesting that both Thyreophora and neornithischians could have achieved significant convergent features. The specimen was preserved articulated and with some of its gut content place in the middle-posterior part of the thoracic cavity. Such stomach content was identified as seeds, most of them belonging to the Cycadales group. This finding reveals a possible and unexpected role of this ornithischian species as seed-dispersal agent.Facultad de Ciencias Naturales y Muse
Ion Exchange in Geopolymers
Geopolymers have been widely used for construction and building materials. Nevertheless, some other applications have been found from their ability to be ion exchanged. An example is the encapsulation of heavy metals, but some others involve the ion exchange of the aluminosilicate structure to form photoactive particles or to link copper ions. In this chapter, we summarize some of the properties which make aluminosilicate inorganic polymer (geopolymers) ion exchangeable: the synthesized temperature, its effect over their porosity and their stoichiometric nature. Also, the effects of ion exchanging a geopolymer with an NH4+Cl, (NH4)2TiO2(C2O4)2 and (CH3)4N+Br are presented. The geopolymer was characterized by FT-IR, XRD, BET and MAS NMR, showing how a 100% of replacement was achieved for NH4+Cl. On the contrary, the efficiency was reduced in (NH4)2TiO2(C2O4)2 and (CH3)4N+Br, effect ascribed to the fact of the molecular size that did not allow the counterions to reach the aluminum atoms in the geopolymer. Finally, the procedure followed to ion exchange a metakaolinite-based geopolymer is described, and the potential applications related are presented
Spatial location patterns of mexican manufacturing: analysis using the technique of spatial points patterns
This paper explores the spatial location patterns of firms in
different
sectors of the Mexican manufacturing industry. The analysi
s is carried
out using a continuous spatial statistic approach by employ
ing a K-
function for each sector that is then compared to a Complete S
patial
Randomness (CSR) distribution and other relevant benchmar
ks. We
show that Mexican manufacturing follows a bimodal distribu
tion and
significant spatial concentrations are present for all manu
facturing sec-
tors at different distances. However, using the spatial dist
ribution of
the complete set of manufactures as a point of reference, var
iations in
the spatial distribution are also found to exist.Se analizan los patrones de localizaci ́on espacial de los di
ferentes sec-
tores que componen las manufacturas mexicanas sobre un espa
cio con-
tinuo. Se hace utilizando la funci ́on K de Ripley, t ́ecnica b
asada en
la distancia que permite tratar el espacio como continuo. Al
utilizar
como referencia la CSR (
Complete Spatial Randomnes
) se encontraron
concentraciones espaciales significativas para todos los s
ectores manu-
factureros a diferentes rangos de distancia. Asimismo, se d
etect ́o que
la estructura espacial de las manufacturas es bimodal. Sin e
mbargo,
al usar la distribuci ́on espacial del conjunto de las manufa
cturas como
punto de referencia se han obtenido variaciones en la distri
buci ́on es-
pacial
Una asociación multi-ootáxica del Cretácico Inferior de la Cuenca de Cameros (La Rioja; Norte de España
Fil: Moreno Azanza, Miguel. Universidade Nova de Lisboa; Portugal.Fil: Moreno Azanza, Miguel. Universidad de Zaragoza; EspañaFil: Gasca Pérez, José M. Universidad de Zaragoza; EspañaFil: Gasca Pérez, José M. Provincia de Neuquén. Ministerio de Energía, Ambiente y Servicios Públicos. Dirección Provincial de Minería. Museo Provincial de Ciencias Naturales Prof. "Dr. Juan A. Olsacher"; ArgentinaFil: Díaz Martínez, Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Díaz Martínez, Ignacio. Universidad Nacional de Río Negro; ArgentinaFil: Bauluz Lázaro, Blanca. Universidad de Zaragoza; EspañaFil: Canudo, José I. Universidad de Zaragoza; EspañaFil: Fernández, Arturo. Asociación de Amigos del Museo de Enciso; EspañaFil: Pérez Lorente, Félix. Universidad de La Rioja; EspañaHere we describe the new fossil site of El Horcajo in the vicinity of Trevijano (La Rioja, Spain). It is located in the palustrine facies of the Enciso Group (Cameros Basin). This new locality has provided dozens of eggshell fragments, together with other vertebrate remains and charophyte fructifications, which allow dating of the locality as Valanginian-Hauterivian. Five ootaxa have being recognized: 1) the Spheroolithidae Guegoolithus turolensis; 2) a surprisingly thick Prismatoolithidae indet., with certain affi nities to the oogenus Sankofa, that may represent a new oogenus and oospecies for this oofamily; 3) the Krokolithidae Krokolithes sp.; 4) recrystallized ?Testudoolithidae eggshells; and 5) ?Geckoolithidae eggshells of uncertain affi nity. This oodiversity is similar to that of other eggshell microsites. The ootaxonomic list differs from the other Iberian locality of the same age, Pochancalo 1 (Villanueva de Huerva Formation, Zaragoza) in lacking sauropod and megalosauroid theropod eggshells, but shares the presence the ornithopod and coelurosaurian theropod eggshells with other younger microsites found in similar facies. The age of the new locality has immediate consequences for the tectono-sedimentary framework of the Cameros Basin, and the new data will need to be considered in future stratigraphical works. Furthermore, the reliability of eggshells as biostratigraphic markers is questioned, and the viability of Guegoolithus as a guide fossil for the lower Barremian is rejected.En este trabajo se describe el nuevo yacimiento fosilífero de El Horcajo en las cercanías de Trevijano (La Rioja, España). Se encuentra en facies palustres dentro del Grupo Enciso (Cuenca de Cameros). Este nuevo yacimiento ha proporcionado docenas de fragmentos de cáscara de huevo, junto con otros restos fósiles de vertebrados y fructifi caciones de carofi tas, que permiten datar el yacimiento como ValanginienseHauteriviense. Se han identificado cinco ootaxones: 1) Guegoolithus turolensis, de la oofamilia Spheroolithidae; 2) un Prismatoolithidae indet. sorprendentemente grueso y con afi nidades al oogénero Sankofa, que podría corresponder a un nuevo oogénero y ooespecie; 3) Krokolithes sp. de la oofamilia Krokolithidae; 4) cáscaras recristalizadas asignables con dudas a Testudoolithidae; y 5) cáscaras de afi nidad incierta, aquí asignadas con dudas a Geckoolithidae. Esta oodiversidad es similar a la de otros microyacimientos de cáscaras de huevo. La lista ootaxonómica difi ere de la obtenida en la otra única localidad de esta edad en Iberia, Pochancalo 1 (Formación Villanueva de Huerva, Zaragoza), por la ausencia de cáscaras de huevo asignables a saurópodos y terópodos megalosauroideos, pero comparte la presencia de cáscaras de huevo asignables a ornitópodos y terópodos celurosaurios con otros yacimientos más recientes que muestran facies similares. Este nuevo yacimiento tiene consecuencias inmediatas para el marco tectono-sedimentario de la cuenca de Cameros, siendo necesario considerar estos nuevos datos en futuros estudios estratigráfi cos. Además, se cuestiona la fi abilidad del uso de cáscaras de huevo como marcadores bioestratigráfi cos, ya que los nuevos datos ponen en duda la utilidad de Guegoolithus como fósil guía para el Barremiense inferior
Latest Cretaceous palaeogeographic evolution of northeast Iberia: Insights from the Campanian continental Montalbán subbasin (Spain)
This work characterizes for the first time the 500–700 m-thick uppermost Cretaceous continental sedimentary succession of the Allueva Fm recorded in the northeastern margin of the Iberian basin, in the Montalbán subbasin (Maestrazgo domain, Spain). The middle-upper Campanian age of this unit constrained here by new paleomagnetic and biostratigraphic data involves major revision of previous stratigraphic and palaeogeographic interpretations. The uplift of the northern marginal areas of the Montalbán subbasin onwards from the middle Campanian supplied the coarse terrigenous-clastic sediments common in the alluvial Allueva Fm. Moreover, a sharp increase of the sedimentation rates (from 4 to 19 cm/ky) from the lower to the middle-upper part of the Allueva Fm has been related to further increase of the tectonic activity during the middle part of the late Campanian. Also relevant are the new discovered vertebrate sites mostly found in the marginal areas of a large lacustrine-palustrine carbonate system developed during the latest Campanian. Vertebrate sites include a fossil assemblage with abundance of titanosaur sauropod dinosaurs as well as the presence of ornithopod dinosaurs and crocodylomorphs. A review of the dinosaur fossil sites recorded in other Iberian subbasins shows a similar fossil assembage occurrence during the late Campanian–earliest Maastrichtian timespan, previous to the faunal turnover that took place in the Ibero-Armorican landmass around the onset of the late Maastrichtian. The stratigraphic, sedimentological and paleontological characterization of the successions recorded during the initial stages of development of the Montalbán subbasin have major implication to understand the latest Cretaceous palaeogeographic evolution of northeast Iberia. Comparative review to other latest Cretaceous continental successions deposited in other domains of the Iberian basin indicates a south to north migration of newly developed subsident subbasins: during the Campanian (South Iberian domain), during the middle-late Campanian (northern Maestrazgo domain), and during the Maastrichtian (central Castillian domain)
The state of art of the drought studies in Spain
Póster elaborado para el WCRP Workshop on Drought Predictability and Prediction in a Changing Climate celebrado en Barcelona del 2 al 4 de marzo de 201
A new primitive Neornithischian dinosaur from the Jurassic of Patagonia with gut contents
We describe a new species of an ornithischian dinosaur, Isaberrysaura mollensis gen. et sp. nov. The specimen, consisting in an almost complete skull and incomplete postcranium was collected from the marine-deltaic deposits of the Los Molles Formation (Toarcian-Bajocian), being the first reported dinosaur for this unit, one of the oldest from Neuquén Basin, and the first neornithischian dinosaur known from the Jurassic of South America. Despite showing a general stegosaurian appearance, the extensive phylogenetic analysis carried out depicts Isaberrysaura mollensis gen. et sp. nov. as a basal ornithopod, suggesting that both Thyreophora and neornithischians could have achieved significant convergent features. The specimen was preserved articulated and with some of its gut content place in the middle-posterior part of the thoracic cavity. Such stomach content was identified as seeds, most of them belonging to the Cycadales group. This finding reveals a possible and unexpected role of this ornithischian species as seed-dispersal agent.Facultad de Ciencias Naturales y Muse
Inhibition of Yeast Hexokinase by Acyl Glucosides of Phloretin and its Implication in the Warburg Effect
Contrary to differentiated cells, cancer cells predominantly convert glucose to lactate even under conditions of adequate oxygen supply (“Warburg effect”). The initial enzyme implicated in this route is hexokinase, which transforms D-glucose into D-glucose-6-phosphate. We proposed the use of different polyphenols (resveratrol, epigallocatechin gallate, pterostilbene, phloretin) and their derivatives (α-glucosides and acylated α-glucosides) to inhibit this enzyme. For this study, we used Saccharomyces cerevisiae hexokinase, whose two isoforms show high resemblance at the active site with human hexokinase HK2. To monitor the reactions, a method of anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD) was developed. Remarkably, most of the assayed compounds inhibited the enzyme more than 50 % in the standard assay. Among them, phloretin 4’-O-(6’’-O-octanoyl)-α-D-glucopyranoside showed the highest inhibition and was studied in depth to determine the inhibition pattern and inhibition constant. The Ki for glucose was calculated to be 22.1±0.4 μM. Computational models of inhibition were carried out with the three molecules displaying the highest inhibition, and correlated adequately with the observed inhibitory effects on the enzyme. The inhibitory effect of several of the assayed polyphenols on hexokinase and their lack of toxicity renders them promising candidates as adjuvant drugs for cancer therapy.This work was supported by: (1) Grant PDC2022-133134-C21 “ACYLGLUFLAV_APP” funded by MCIN/AEI/10.13039/501100011033 by the “European Union Next Generation EU/PRTR”; (2) Grant PID2019-105838RB−C31 “GLYCOENZ-PHARMA” funded by MCIN/AEI/10.13039/501100011033; (3) Grant PID2022-136367OB−C31 “GLYCOENZ-GREEN” funded by MCIN/AEI/10.13039/501100011033/ and through FEDER, a Way of Making Europe (4) Grant CM_5779 “Programa Investigo” (Madrid Region, Call 2022, European Union Next Generation EU). We thank Carlos Uceda for technical help.Peer reviewe
Overproduction of a Trichoderma harzianum chitinase and analysis of its biotechnological potential to produce chitooligosaccharides
Trabajo presentado en la 7ª ed. del congreso internacional "FEMS" organizado por la Sociedad Española de Microbiología y la Federación Europea de Sociedades Microbiológicas en el Centro de Convenciones Feria Valencia (Valencia, España) durante los días 9 al 13 de julio de 2017.BACKGROUNDS: Chitooligosaccharides (COS) are β-(1,4)-linked oligomers of N-acetyl-glucosamine (GlcNAc) and glucosamine (GlcN) formed by chemical or enzymatic hydrolysis of chitosan or chitin. The growing biotechnological interest of COS in fields such as food or health increases the demand of the producing enzymes as well as their characterization and functional improvement. | OBJETIVES: Express a chitinase of 42 kDa from Trichoderma harzianum in a heterologous system, obtain protein levels compatible with its crystallization for the future protein structural resolution and evaluate the ability of the recombinant protein to produce COS. | METHODS: The chitinase gene cDNA from T. harzianum was expressed in Pichia pastoris using a restriction-free cloning strategy, production of heterologous protein was analysed and escalated up to a 5 L fermenter level. Recombinant protein was purified and some crystals were obtained which allows undertake the protein structural resolution. Synthesis of oligosaccharides from different substrates were evaluated and optimized using the recombinant enzyme. HPAEC-PAD on a Dionex ICS3000 system and Mass Spectrometry were used in the reaction studies and product characterization. | CONCLUSIONS: A chitinase of 42 kDa from T. harzianum was overexpressed in P. pastoris, the recombinant protein was purified, characterized and crystallized for the protein structural resolution. Production of COS mediated by this enzyme was evaluated and some of the molecules formed were characterized.N
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