1,335 research outputs found
Accurate placement of epiescleral plaque in brachytherapy of choroideal melanoma
SalvadĂł Jassans, JosepPla general de l'obra: A LluĂs Millet. Es veu la figura, en bronze,
del mĂșsic i fundador de l'OrfeĂł CatalĂ , en el gest de dirigir.
EstĂ situada a l'exterior del Palau de la MĂșsica Catalana
Neonatal exposure to xenoestrogens impairs the ovarian response to gonadotropin treatment in lambs
Bisphenol A (BPA) and diethylstilbestrol (DES) are xenoestrogens which have been associated with altered effects on reproduction. We hypothesized that neonatal xenoestrogen exposure affects the ovarian functionality in lambs. Thus, we evaluated the ovarian response to exogenous ovine Follicle Stimulating Hormone (oFSH) administered from postnatal day 30 (PND30) to PND32 in female lambs previously exposed to low doses of DES or BPA (BPA50: 50 ÎŒg/kg.day, BPA0.5: 0.5 ÎŒg/kg.day) from PND1 to PND14. We determined: a) follicular growth, b) circulating levels of E2, c) steroid receptors (ERA, ERB, AR) and atresia, d) mRNA expression levels of the ovarian bone morphogenetic protein (BMPs) system (BMP6, BMP15, BMP receptor type 1B, GDF9) and FSH receptor (FSHR). Lambs neonatally exposed to DES or BPA showed an impaired ovarian response to oFSH with a lower number of follicles â„2 mm together with a lower number of atretic follicles and no increase in E2 serum levels in response to oFSH treatment. In addition, AR induction by oFSH was disrupted in granulosa and theca cells of lambs exposed to DES or BPA. An increase in GDF9 mRNA expression levels was observed in oFSH-primed lambs previously treated with DES or BPA50. In contrast, a decrease in BMPR1B was observed in BPA0.5-postnatally exposed lambs. The modifications in AR, GDF9 and BMPR1B may be associated with the altered ovarian function due to neonatal xenoestrogen exposure in response to an exogenous gonadotropin stimulus. These alterations may be the pathophysiological basis of subfertility syndrome in adulthood.Fil: Rivera, Oscar E.. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias; ArgentinaFil: Varayoud, Jorgelina Guadalupe. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: Rodriguez, Horacio Adolfo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: SantamarĂa, Clarisa Guillermina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: Bosquiazzo, Veronica Lis. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: Osti, Mario. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: Belmonte, Norberto Miguel. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias; ArgentinaFil: Muñoz de Toro, Monica Milagros. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; ArgentinaFil: Luque, Enrique Hugo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Santa Fe. Instituto de Salud y Ambiente del Litoral. Universidad Nacional del Litoral. Instituto de Salud y Ambiente del Litoral; Argentin
Carnivore-Livestock Conflicts in Chile: Evidence and Methods for Mitigation
Human population growth and habitat loss have exacerbated humanâwildlife conflicts worldwide. We explored trends in humanâwildlife conflicts (HWCs) in Chile using scientific and official reports to identify areas and species with higher risk of conflicts and tools available for their prevention and mitigation. The puma (Puma concolor) was considered the most frequent predator; however, fox (Lycalopex spp.) and free-ranging or feral dog (Canis lupus familiaris) attacks were also common. Our results suggest that the magnitude of puma conflicts may be overestimated. Domestic sheep (Ovis spp.) and poultry (Galliformes) were the most common species predated. Livestock losses were widespread across Chile but were highest in San Jose de Maipo, located in central Chile, and Cochrane, La UniĂłn, and Lago Verde in south Chile municipalities. Livestock guardian dogs and the livestock insurance, as a part of the Agriculture Insurance of Chile, were identified as the most promising tools to mitigate HWCs, short- and mid-term, respectively. However, longer-term strategies should focus on improving livestock management through extension (i.e., farmer education) programs for local communities. In Chile, HWCs negatively impact small farmers and wild carnivore populations. An interinstitutional and interdisciplinary strategy integrating input from government and nongovernmental organizations, farmers, and academia is needed to achieve effective carnivore conservation in the long-term
Redox and Catalytic Properties of Promoted NiO Catalysts for the Oxidative Dehydrogenation of Ethane
[EN] NiO and metal-promoted NiO catalysts (M-NiO, with a M/(M+Ni) atomic ratio of 0.08, with M = Nb, Sn, or La) have been prepared, tested in the oxidative dehydrogenation (ODH) of ethane, and characterized by means of XRD, TPR, HRTEM, Raman, XPS, and in situ XAS (using H-2/He, air or C2H6/He mixtures). The selectivity to ethylene during the ODH of ethane decreases according to the following trend: Nb NiO Sn NiO > La NiO > NiO, whereas the catalyst reducibility (determined by both TPR and XAS using H-2/He mixtures) shows the opposite trend. However, different reducibility and catalytic behavior in the absence of oxygen (ethane/He mixtures) have been observed, especially when comparing Nb- and Sn-promoted NiO samples. These differences can be ascribed mainly to a different phase distribution of the promoter. The results presented here are discussed in terms of the nature of active and selective sites for ODH of ethane in selective and unselective catalysts, but also the role of promoters and the importance of their phase distribution.The authors would like to acknowledge the DGICYT in Spain CTQ2012-37925-C03-2, CTQ2015-68951-C3-1-R, and CTQ2015-68951-C3-3-R. Authors thank European Synchrotron Radiation Facility, ESRF (Project CH-4512; BM25-SpLine Beamlime). Authors from ITQ also thank Project SEV-2016-0683 for financial support. D.D. thanks MINECO and Severo Ochoa Excellence Program for his fellowship (SVP-2014-068669). B.S. also thanks UV-INV-AE16-484416. Finally, the authors thank the Electron Microscopy Service of Universitat Politecnica de Valencia for their support.Delgado-Muñoz, D.; Solsona Espriu, BE.; Ykrelef, A.; Rodriguez-Gomez, A.; Caballero, A.; RodrĂguez-Aguado, E.; Rodriguez-CastellĂłn, E.... (2017). Redox and Catalytic Properties of Promoted NiO Catalysts for the Oxidative Dehydrogenation of Ethane. The Journal of Physical Chemistry C. 121(45):25132-25142. https://doi.org/10.1021/acs.jpcc.7b07066S25132251421214
Electronic structure of cubic SrHfOâ: Ferroelectric stability and detailed comparison with SrTiOâ
Electronic structure calculations of cubic SrTiOâ and SrHfOâ are presented. The full-potential linear augmented-plane-wave method is used and exchange-correlation effects are treated by the local-density approximation. The tendency to ferroelectricity of both compounds is explored and compared by displacing the transition metal atom (Ti or Hf) towards one of the oxygens (001 direction). The calculations show that ferroelectricity is favored in SrTiOâ with respect to SrHfOâ and that this fact may be correlated with the degree of hybridization between transition metal d-O p bands as has been found for other related systems. Also a detailed discussion of the calculated electric field gradients is presented
Cysteine-proteases and cystatins from barley: molecular and functional characterization in housekeeping and defense processes
Plant cysteine-proteases (CysProt) represent a well-characterized type of proteolytic enzymes that fulfill tightly regulated physiological functions (senescence and seed germination among others) and defense roles. This article is focused on the group of papain-proteases C1A (family C1, clan CA) and their inhibitors, phytocystatins (PhyCys). In particular, the proteaseâinhibitor interaction and their mutual participation in specific pathways throughout the plant's life are reviewed. C1A CysProt and PhyCys have been molecularly characterized, and comparative sequence analyses have identified consensus functional motifs. A correlation can be established between the number of identified CysProt and PhyCys in angiosperms. Thus, evolutionary forces may have determined a control role of cystatins on both endogenous and pest-exogenous proteases in these species. Tagging the proteases and inhibitors with fluorescence proteins revealed common patterns of subcellular localization in the endoplasmic reticulumâGolgi network in transiently transformed onion epidermal cells. Further in vivo interactions were demonstrated by bimolecular fluorescent complementation, suggesting their participation in the same physiological processes
Collective vs local measurements in qubit mixed state estimation
We discuss the problem of estimating a general (mixed) qubit state. We give
the optimal guess that can be inferred from any given set of measurements. For
collective measurements and for a large number of copies, we show that the
error in the estimation goes as 1/N. For local measurements we focus on the
simpler case of states lying on the equatorial plane of the Bloch sphere. We
show that standard tomographic techniques lead to an error proportional to
, while with our optimal data processing it is proportional to
.Comment: 4 pages, 1 figure, minor style changes, refs. adde
Fossil Groups Origins III. Characterization of the sample and observational properties of fossil systems
(Abridged) Fossil systems are group- or cluster-sized objects whose
luminosity is dominated by a very massive central galaxy. In the current cold
dark matter scenario, these objects formed hierarchically at an early epoch of
the Universe and then slowly evolved until present day. That is the reason why
they are called {\it fossils}. We started an extensive observational program to
characterize a sample of 34 fossil group candidates spanning a broad range of
physical properties. Deep band images were taken for each candidate and
optical spectroscopic observations were obtained for 1200 galaxies. This
new dataset was completed with SDSS DR7 archival data to obtain robust cluster
membership and global properties of each fossil group candidate. For each
system, we recomputed the magnitude gaps between the two brightest galaxies
() and the first and fourth ranked galaxies ()
within 0.5 . We consider fossil systems those with mag or mag within the errors. We find
that 15 candidates turned out to be fossil systems. Their observational
properties agree with those of non-fossil systems. Both follow the same
correlations, but fossils are always extreme cases. In particular, they host
the brightest central galaxies and the fraction of total galaxy light enclosed
in the central galaxy is larger in fossil than in non-fossil systems. Finally,
we confirm the existence of genuine fossil clusters. Combining our results with
others in the literature, we favor the merging scenario in which fossil systems
formed due to mergers of galaxies. The large magnitude gap is a
consequence of the extreme merger ratio within fossil systems and therefore it
is an evolutionary effect. Moreover, we suggest that at least one candidate in
our sample could represent a transitional fossil stage.Comment: 14 pages, 11 figures, accepted for publication in A&
SHARDS: Constraints on the dust attenuation law of star-forming galaxies at z~2
We make use of SHARDS, an ultra-deep (<26.5AB) galaxy survey that provides
optical photo-spectra at resolution R~50, via medium band filters (FWHM~150A).
This dataset is combined with ancillary optical and NIR fluxes to constrain the
dust attenuation law in the rest-frame NUV region of star-forming galaxies
within the redshift window 1.5<z<3. We focus on the NUV bump strength (B) and
the total-to-selective extinction ratio (Rv), targeting a sample of 1,753
galaxies. By comparing the data with a set of population synthesis models
coupled to a parametric dust attenuation law, we constrain Rv and B, as well as
the colour excess, E(B-V). We find a correlation between Rv and B, that can be
interpreted either as a result of the grain size distribution, or a variation
of the dust geometry among galaxies. According to the former, small dust grains
are associated with a stronger NUV bump. The latter would lead to a range of
clumpiness in the distribution of dust within the interstellar medium of
star-forming galaxies. The observed wide range of NUV bump strengths can lead
to a systematic in the interpretation of the UV slope () typically used
to characterize the dust content. In this study we quantify these variations,
concluding that the effects are ~0.4.Comment: 13 pages, 11+2 figures, 3 tables. MNRAS, in pres
Phytochemical Characterization and Antiplatelet Activity of Mexican Red Wines and Their By-products
Red wines and their grape pomaces are important sources of phenolic compounds. Inhibition of plateletaggregation is one of the mechanisms proposed for cardioprotective effect of phenolic compounds fromwine and grape pomace; however, phenolic content is affected by region, variety and winemaking process.In the present study, antiplatelet effect of red wines and grape pomaces was related to its phenolic content(determined by spectrophotometric techniques) and profile (determined using HPLC-MS/MS). in vitroAnti-platelet aggregation was determined using human platelets. Results showed that Zinfandel wine andCabernet Sauvignon grape pomace presented the highest phenolic content. Phenolic profiles presenteddifferences in the presence of flavonoids and oligomeric tannins. Results from platelet aggregationshowed that Merlot and Petit Verdot wines and Petit Verdot grape pomace sample presented the highestantiaggregant effect. These results indicate that antiplatelet effect could be related to phenolic profile thanphenolic content in wines and grape pomaces. Cardioprotective effect of red wines and grape pomacecould be related to specific compounds such as monomeric and polymeric flavan-3-ols
- âŠ