Posidonia oceanica (L.) Delile in its westernmost biogeographical limit (northwestern Alboran Sea): Meadows characterisation, phenology and flowering events

Mateo-Ramírez A, Urra J, Rueda J, Marina, Bañares-España E, García Raso E. (2016) Posidonia oceanica (L.) Delile in its westernmost biogeographical limit (northwestern Alboran Sea): Meadows characterisation, phenology and flowering events. Front. Mar, Sci. Conference Abstract: XIX Iberian Symposium on Marine Biology Studies. doi: 10.3389/conf.FMARS.2016.05.00055Posidonia oceanica is a Mediterranean endemic seagrass species that forms meadows covering ca. 2.5–4.5 millions of hectares, representing ca.25 % of the infralittoral and shallow circalittoral (down to 50m) bottoms of the Mediterranean. This seagrass is considered a habitat-engineer species and provides an elevated number of ecosystem services. In addition the Marine Strategy Framework Directive (MSFD, 2008/56/EC) includes seagrass like elements to evaluate the “Good Environmental Status” of the European coasts. Information about their phenological characteristic and structure of the meadows is needed for indicator estimations in order to establish their conservation status. The studied meadows are located in the westernmost limit of the P. oceanica distribution (North-western Alboran Sea) in the vecinity of the Strait of Gibraltar, an Atlantic-Mediterranean water transition area. Four sites were selected from East to West: Paraje Natural de Acantilados de Maro-Cerro Gordo (hereafter Maro), Special Area of Conservation “Calahonda” (hereafter Calahonda), Site of Community Importance Estepona (hereafter Estepona) and Punta Chullera (hereafter Chullera) where P. oceanica present their westernmost meadows. Phenological data were recorded from mid November to mid December in P. oceanica patches located at 2 – 3 m depth. At each site three types of patches (patch area 2 m2, large patches) were sampled. At each patch and site, 3 quadrants of 45 x 45 cm were sampled for shoot and inflorescences density measurements. In each quadrant, 10 random shoots were sampled for shoot morphology (shoot height and number of leaves). Shoot and inflorescences densities were standardized to squared meters. All the studied P. oceanica meadows develop on rocks and they present a fragmented structure with a coverage ranging between ca. 45% in Calahonda and Estepona and ca. 31% in Maro. The meadows of Chullera are reduced to a few small - medium patches with areas ranging between 0.5-1.5 m2 (Fig. 1). The meadows of Chullera and Estepona presented similar values of shoot density (ca. 752 – 662 shoots m-2, respectively) and leaf height (ca. 25 cm). Similarly, the Calahonda and Maro meadows also showed similar values of shoot density (ca. 510 – 550 shoots m-2, respectively) but displaying lower values than those of sites located closer to the Strait of Gibraltar. Regarding patch sizes and leaf height, the longest leaves (ca. 25 cm) were found in medium and large patches, but the number of leaves per shoot were higher in the small and the medium size patches (ca. 6.3 leaves per shoot). Flowering was only detected at the Calahonda meadows with maximum values of ca. 330 inflorescences m-2 (115.2 ± 98.2 inflorescences m-2, n= 9; mean ± SD) (Fig.1). Inflorescence density was not significant different among patches of different sizes. In the Alboran Sea and unlike the studied meadows, extensive beds of P. oceanica occur at the National Park of Cabo de Gata (northeastern Alboran Sea), but from east to west (Strait of Gibraltar), meadows are gradually fragmenting and their depth range decrease from 30m to 2m depth between Cabo de Gata and Chullera, respectively. Probably, the Atlantic influence and the characteristic oceanographic conditions of the Alboran Sea (i.e., higher turbidity, higher water turbulence) represent a developmental limiting factor for P. oceanica at higher depths. Similarities between the meadows located closer to Strait of Gibraltar (Chullera and Estepona) were detected as well as between those more distant (Calahonda and Maro). The first ones showed higher values of shoot densities and leaf heights than the formers, which could be relating to the higher hydrodynamic exposure found at Chullera and Estepona meadows. Regarding flowering events, sexual reproduction in P. oceanica is not common in different locations of the Mediterranean Sea. The available information seems to indicate that flowering represent an irregular event and it is related to high seawater temperature. In fact, the flowering episodes that occurred in Calahonda in November 2015, match with the warmest year ever recorded. This is the third flowering event registered in these meadows located close to the westernmost distributional limit of P. oceanica (Málaga, Alboran Sea), which could indicates that these meadows presents a healthy status. Furthermore, the absence of significant differences in relation to inflorescence density between patches of different sizes may be indicating that the fragmentation does not necessarily influence on the flowering of this seagrass species.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Oxidation of o-xylene to phthalic anhydride on Sb-V/ZrO2 catalysts

Zirconia-supported and bulk-mixed vanadium-antimonium catalysts were used for the oxidation of o-xylene to phthalic anhydride. Vanadium promoted the transition of tetragonal to monoclinic zirconia. The simultaneous presence of antimony and vanadium on zirconia at low coverage led to a preferential interaction of individual V and Sb oxides with the zirconia surface rather than the formation of a binary Sb-V oxide, while at higher Sb-V contents, the formation of SbVO4 took place. Sb-V-ZrO2 catalysts showed high activity for o-xylene conversion and better selectivity to phthalic anhydride as compared to V/ZrO2 catalysts. However, their selectivity to phthalic anhydride was poor compared to V/TiO2 commercial catalysts. The improved selectivity of the Sb-containing catalysts was attributed to the blocking of non-effective surface sites of ZrO2, the decrease of the total amount of acid sites and the formation of surface V-O-Sb-O-V structures.Fil: Pieck, Carlos Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Catálisis y Petroleoquímica; EspañaFil: del Val, S.. Instituto de Catálisis y Petroleoquímica; EspañaFil: López Granados, M.. Instituto de Catálisis y Petroleoquímica; EspañaFil: Bañares, M.A.. Instituto de Catálisis y Petroleoquímica; EspañaFil: Fierro, J.L.G.. Instituto de Catálisis y Petroleoquímica; Españ

Soil and climate drive floristic composition in tropical forests: a literature review

A vast literature indicates that environment plays a paramount role in determining floristic composition in tropical forests. However, it remains unclear which are the most important environmental factors and their relative effect across different spatial scales, plant life forms or forest types. This study reviews the state of knowledge on the effect of soil and climate on floristic composition in tropical forests. From 137 publications, we collated information regarding: (1) spatial scale, continent, country, life form, and forest type; (2) proportion of variance in floristic composition explained by soil and climatic variables and how it varies across spatial scales; and (3) which soil and climate variables had a significant relationship on community composition for each life form and forest type. Most studies were conducted at landscape spatial scales (67%) and mainly in South America (74%), particularly in Brazil (40%). Studies majorly focused on trees (82%) and on lowland evergreen tropical forests (74%). Both soil and climate variables explained in average the same amount (14% each) of the variation observed in plant species composition, although soils appear to exert a stronger influence at smaller spatial scales while climate effect increases toward larger ones. Temperature, precipitation, seasonality, soil moisture, soil texture, aluminum, and base cations—calcium and magnesium–and their related variables (e.g., cation exchange capacity, or base saturation) were frequently reported as important variables in structuring plant communities. Yet there was variability when comparing different life forms or forest types, which renders clues about certain ecological peculiarities. We recommend the use of standardized protocols for collecting environmental and floristic information in as much as possible, and to fill knowledge gaps in certain geographic regions. These actions will be especially beneficial to share uniform data between researchers, conduct analysis at large spatial scales and get a better understanding of the link between soils and climate gradients and plant strategies, which is key to propose better conservation policies under the light of global chang

Femtosecond XUV induced dynamics of the methyl iodide cation

Ultrashort XUV wavelength-selected pulses obtained with high harmonic generation are used to study the dynamics of molecular cations with state-to-state resolution. We demonstrate this by XUV pump - IR probe experiments on CH3I+ cations and identify both resonant and non-resonant dynamics

Dataset for proteomic analysis of Chlorella sorokiniana cells under cadmium stress

Cadmium is one of the most hazardous heavy metal for aquatic environments and one of the most toxic contaminants for phytoplankton. This work provides the dataset associated with the research publication “Effect of cadmium in the microalga Chlorella sorokiniana : a proteomic study” [1] . This dataset describes a proteomic approach, based on the sequential window acquisition of all theoretical fragment ion spectra mass spectrometry (SWATH-MS), derived from exposure of Chlorella sorokiniana to 250 μM Cd 2 + for 40 h, showing the proteins that are up- or downregulated. The processing of data included the identification of the Chlamydomonas reinhardtii protein sequences equivalent to the corresponding of Chlorella sorokiniana sequences obtained, which made possible to use KEGG Database. MS and MS/MS information, and quantitative data were deposited PRIDE public repository under accession number PXD015932 .This work was supported in part by research grants from the European governments (IN- TERREG VA-POCTEP- 2014-2020; 0055_ALGARED_PLUS_5_E), the Operative FEDER Program- Andalucía 2014-2020 ( UHU-1257518 ) University of Huelva and by the European Regional De- velopment Fund through the Agencia Estatal de Investigación grants ( PID 2019-110438RB-C22 and PID 2019-109785 GB-100 )

The dynamics of the hydrogen exchange reaction at 2.20 eV collision energy: Comparison of experimental and theoretical differential cross sections

The H+D2(v = 0, j = 0)→HD(v′, j′)+D isotopic variant of the hydrogen atom exchange reaction has been studied in a crossed molecular beam experiment at a collision energy of 2.20 eV. Kinetic energy spectra of the nascent D atoms were obtained by using the Rydberg atom time-of-flight technique. The extensive set of spectra collected has permitted the derivation of rovibrationally state-resolved differential cross sections in the center-of-mass frame for most of the internal states of the HD product molecules, allowing a direct comparison with theoretical predictions. Accurate 3D quantum mechanical calculations have been carried out on the refined version of the latest Boothroyd-Keogh-Martin-Peterson potential energy surface, yielding an excellent agreement with the experimentally determined differential cross sections. The comparison of the results from quasi-classical trajectory calculations on the same potential surface reveals some discrepancies with the measured data, but shows a good global accordance. The theoretical calculations demonstrate that, at this energy, reactive encounters are predominantly noncollinear and that collinear collisions lead mostly to nonreactive recrossing. The experimental results are satisfactorily accounted for by theoretical calculations without consideration of Geometric Phase effects. © 1999 American Institute of Physics.Financial support through the program ‘‘Acciones para la Incorporación de Doctores y Tecnólogos’’ of the Ministry of Education and Culture of Spain. We also gratefully acknowledge the computer resources ~Cray T-90! provided by the Leibniz Rechenzentrum in Munich ~Germany. Funded by the German Science Foundation ~Grant No. SCH 435/3! and the Deutscher Akademischer Austauchdienst‘‘Acciones Integradas’’. The Spanish part was financed by the DGICYT ~PB95-0918-C03! and by the ‘‘Acciones Integradas’’ Program of the Ministry of Educationand Culture.Peer Reviewe

A detailed quantum mechanical and quasiclassical trajectory study on the dynamics of the H(+) + H2 --> H2 + H(+) exchange reaction

13 pages, 11 figures.-- PACS nrs.: 82.30.Hk; 82.30.Nr.The H(+) + H2 exchange reaction has been studied theoretically by means of a different variety of methods as an exact time independent quantum mechanical, approximate quantum wave packet, statistical quantum, and quasiclassical trajectory approaches. Total and state-to-state reaction probabilities in terms of the collision energy for different values of the total angular momentum obtained with these methods are compared. The dynamics of the reaction is extensively studied at the collision energy of E(coll) = 0.44 eV. Integral and differential cross sections and opacity functions at this collision energy have been calculated. In particular, the fairly good description of the exact quantum results provided by the statistical quantum method suggests that the dynamics of the process is governed by an insertion mechanism with the formation of a long-lived collision complex.Two of the authors (O.R. and T.G.L.) thank the Spanish Ministry of Education (MEC) for financial support through Grants Nos. FIS2004-02461 and CTQ2004-02415. One of the authors (T.G.L.) would like to acknowledge support from the program Ramón y Cajal of Spanish MEC and EU Grant No. MERG-CT-2004-513600. Two other authors (F.J.A. and L.B.) acknowledge financial support through MEC Grant No. CTQ2005-08493-C02-01 and Universidad Complutense- Comunidad de Madrid Grant No. 910729. Another author (N.B.) thanks a postdoctoral fellowship by Spanish MEC under the program "Estancias de jóvenes doctores y tecnólogos extranjeros en España". One of the authors (F.J.A.) thanks the financial support by the programme of "Sabáticos Complutenses" of the Universidad Complutense de Madrid. The EQM calculations were performed on a NEC-SX5 vector supercomputer, through a grant from the "Institut du Développement des Ressources en Informatique Scientifique" (IDRIS-CNRS) in Orsay (France).Peer reviewe

Fecal Gluten Peptides Reveal Limitations of Serological Tests and Food Questionnaires for Monitoring Gluten-Free Diet in Celiac Disease Patients

Objectives: Treatment for celiac disease (CD) is a lifelong strict gluten-free diet (GFD). Patients should be followed-up with dietary interviews and serology as CD markers to ensure adherence to the diet. However, none of these methods offer an accurate measure of dietary compliance. Our aim was to evaluate the measurement of gluten immunogenic peptides (GIP) in stools as a marker of GFD adherence in CD patients and compare it with traditional methods of GFD monitoring. Methods: We performed a prospective, nonrandomized, multicenter study including 188 CD patients on GFD and 84 healthy controls. Subjects were given a dietary questionnaire and fecal GIP quantified by enzyme-linked immunosorbent assay (ELISA). Serological anti-tissue transglutaminase (anti-tTG) IgA and anti-deamidated gliadin peptide (anti-DGP) IgA antibodies were measured simultaneously. Results: Of the 188 celiac patients, 56 (29.8%) had detectable GIP levels in stools. There was significant association between age and GIP in stools that revealed increasing dietary transgressions with advancing age (39.2% in subjects ≥13 years old) and with gender in certain age groups (60% in men ≥13 years old). No association was found between fecal GIP and dietary questionnaire or anti-tTG antibodies. However, association was detected between GIP and anti-DGP antibodies, although 46 of the 53 GIP stool-positive patients were negative for anti-DGP. Conclusions: Detection of gluten peptides in stools reveals limitations of traditional methods for monitoring GFD in celiac patients. The GIP ELISA enables direct and quantitative assessment of gluten exposure early after ingestion and could aid in the diagnosis and clinical management of nonresponsive CD and refractory CD. Trial registration number NCT02711397

Structural dynamics effects on the ultrafast chemical bond cleavage of a photodissociation reaction

The correlation between chemical structure and dynamics has been explored in a series of molecules with increasing structural complexity in order to investigate its influence on bond cleavage reaction times in a photodissociation event. Femtosecond time-resolved velocity map imaging spectroscopy reveals specificity of the ultrafast carbon–iodine (C–I) bond breakage for a series of linear (unbranched) and branched alkyl iodides, due to the interplay between the pure reaction coordinate and the rest of the degrees of freedom associated with the molecular structure details. Full-dimension time-resolved dynamics calculations support the experimental evidence and provide insight into the structure–dynamics relationship to understand structural control on time-resolved reactivity