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Conserved Curvature of RNA Polymerase Ⅰ Core Promoter Beyond rRNA Genes: The Case of the Tritryps

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Genomics, Proteomics & Bioinformatics 2015年第6期13卷 355-363页

作者： Pablo Smircich María ana Duhagon beatriz Garat Molecular Interactions Laboratory School of Sciences University of the Republic Genetics Departament School of Medicine University of the Republic

In trypanosomatids, the RNA polymerase I （RNAPI）-dependent promoters controlling the ribosomal RNA （rRNA） genes have been well identified. Although the RNAPI transcription machinery recognizes the DNA conformation instead of the DNA sequence of promoters, no con- formational study has been reported for these promoters. Here we present the in silico analysis of the intrinsic DNA curvature of the rRNA gene core promoters in Trypanosoma brucei, Trypanosoma cruzi, and Leiskmania major. We found that, in spite of the absence of sequence conservation, these promoters hold conformational properties similar to other eukaryotic rRNA promoters. Our results also indicated that the intrinsic DNA curvature pattern is conserved within the Leishmania genus and also among strains of T. cruzi and T. brucei. Furthermore, we analyzed the impact of point mutations on the intrinsic curvature and their impact on the promoter activity. Furthermore, we found that the core promoters of protein-coding genes transcribed by RNAPI in T. brucei show the same conserved conformational characteristics. Overall, our results indicate that DNA intrinsic curvature of the rRNA gene core promoters is conserved in these ancient eukaryotes and such con- served curvature might be a requirement of RNAPI machinery for transcription of not only rRNA genes but also protein-coding genes.

关键词： Intrinsic curvature RNA polymerase I Core promoter Trypanosoma Leishmania

Genetic Identification of Quantitative Trait Loci for Contents of Mineral Nutrients in Rice Grain

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Journal of Integrative Plant Biology 2009年第1期51卷 84-92页

作者： ana Luisa garcia-Oliveira Department of Plant Genetics and Breeding and State Key Laboratory of Plant Physiology and Biochemistry China Agricultural University National Centre for Evaluation of Agricultural Wild Plant Rice Beijing Key Laboratory of Crop Genetic Improvement and Genome of Ministry of Agriculture

In present study, Fe, Zn, Mn, Cu, Ca, Mg, P and K contents of 85 introgression lines （ILs） derived from a cross between an elite indica cultivar Teqing and the wild rice （Oryza rufipogon） were measured by inductively coupled argon plasma （ICAP） spectrometry. Substantial variation was observed for all traits and most of the mineral elements were significantly positive correlated or independent except for Fe with Cu. A total of 31 putative quantitative trait loci （QTLs） were detected for these eight mineral elements by single point analysis. Wild rice （O. rufipogon） contributed favorable alleles for most of the QTLs （26 QTLs）, and chromosomes 1,9 and 12 exhibited 14 QTLs （45%） for these traits. One major effect of QTL for zinc content accounted for the largest proportion of phenotypic variation （11%-19%） was detected near the simple sequence repeats marker RM152 on chromosome 8. The co-locations of QTLs for some mineral elements observed in this mapping population suggested the relationship was at a molecular level among these traits and could be helpful for simultaneous improvement of these traits in rice grain by marker assisted selection.

关键词： introgression lines mineral elements Oryza sativa Oryza rufipogon quantitative trait loci.

Effects of melatonin on the oxidative damage and pancreatic antioxidant defenses in ceruleininduced acute pancreatitis in rats

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 442-446页

作者： Cristina Carrasco ana beatriz Rodríguez José A Pariente Department of Physiology Neuroimmunophysiology and Chrononutrition Research Group University of Extremadura

BACKGROUND： Oxidative stress is recognized as a pivotal effector of several pathogenic processes, including acute pancreatitis. Reactive oxygen species not just cause damage on the main cellular components, but also influence the expression of antioxidant system genes. Antioxidant molecules, such as melatonin, could be good candidates for the treatment of this multidimensional disease. The present study was to evaluate the chemopreventive effect of melatonin in a rat model of ceruleininduced acute ***： Four subcutaneous injections of cerulein（20 μg/kg body weight） were given to Wistar rats at two hours intervals;melatonin was injected intraperitoneally（25 mg/kg body weight）30 minutes before each injection of cerulein. Lipid peroxidation,protein oxidation（carbonyl groups）, total antioxidant status,and glutathione peroxidase activity were determined in pancreatic tissue using commercial ***： The chemopreventive administration of melatonin caused a reduction in lipid peroxidation and protein oxidation due to injections of cerulein. Additionally, melatonin treatment was also able to revert glutathione peroxidase activity and total antioxidant status near to control levels, suggesting that melatonin could prevent from oxidative phenomena in the pancreas, such as lipid peroxidation and protein oxidation,and could stimulate, directly or indirectly, the expression of antioxidant ***： Melatonin, a polyvalent antioxidant, protected the pancreatic damage via the decrease of oxidative stress andincrease of the activities of antioxidant enzymes in ceruleininduced acute pancreatitis.

关键词： acute pancreatitis antioxidants cerulein melatonin oxidative stress

Intraexaminer repeatability and agreement in stereoacuity measurements made in young adults

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 374-381页

作者： beatriz Antona ana Barrio Isabel Sanchez Enrique Gonzalez Guadalupe Gonzalez Department of Optics II (Optometry and Vision) Faculty of Optics and Optometry Complutense University of Madrid

AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and ***: Stereoacuity was measured in two different sessions separated by a time interval of at least 24 h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular ***: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability(COR): ±13 and±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was *** the subjects with abnormal binocular vision, best repeatability was shown by the Frisby(COR: ±69s arc)and Randot(COR: ±72s arc). In both groups, the TNO test showed poorest agreement with the other ***:Therepeatabilityofstereoacuitymeasures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.

关键词： stereoacuity repeatability agreement tereopsis

How small could a pup sound？ The physical bases of signaling body size in harbor seals

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Current Zoology 2017年第4期63卷 457-465页

作者： Andrea RAVIGNANI Stephanie GROSS Maxime garcia ana RUBIO-garcia Bart DE BOER Veterinary & Research Department Sealcentre Pieterburen Hoofdstraat 94a Pieterburen AG 9968 The Netherlands Artificial Intelligence Laboratory Vrije Universiteit Brussel Pleinlaan 2 Brussels 1050 Belgium Language and Cognition Department Max Planck Institute for Psycholinguistics Wundtlaan 1 Nijmegen XD 6525 The Netherlands Institute for Terrestrial and Aquatic Wildlife Research University of Veterinary Medicine Hannover Foundation Werftstrasse 6 Buesum 25761 Germany ENES Lab/Neuro-PSI CNRS UMR9197 University of Lyon/Saint Etienne 23 rue Paul Michelon 42023 Saint-Etienne cedex 2 France

Vocal communication is a crucial aspect of animal behavior. The mechanism which most mam- mals use to vocalize relies on three anatomical components. First, air overpressure is generated in- side the lower vocal tract. Second, as the airstream goes through the glottis, sound is produced via vocal fold vibration. Third, this sound is further filtered by the geometry and length of the upper vocal tract. Evidence from mammalian anatomy and bioacoustics suggests that some of these three components may covary with an animal＇s body size. The framework provided by acoustic al- Iometry suggests that, because vocal tract length （VTL） is more strongly constrained by the growth of the body than vocal fold length （VFL）, VTL generates more reliable acoustic cues to an animal＇s size. This hypothesis is often tested acoustically but rarely anatomically, especially in pinnipeds. Here, we test the anatomical bases of the acoustic allometry hypothesis in harbor seal pups Phoca vitulina. We dissected and measured vocal tract, vocal folds, and other anatomical features of 15 harbor seals post-mortem. We found that, while VTL correlates with body size, VFL does not. This suggests that, while body growth puts anatomical constraints on how vocalizations are filtered by harbor seals＇ vocal tract, no such constraints appear to exist on vocal folds, at least during puppy- hood. It is particularly interesting to find anatomical constraints on harbor seals＇ vocal tracts, the same anatomical region partially enabling pups to produce individually distinctive vocalizations.

关键词： acoustic allometry honest signaling larynx pinniped vocal tract.

Warm Forged Medium Carbon V Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 822-826页

作者： Carlos garcia-Mateo beatriz Lopez Jose Maria Rodriguez-Ibabe MATERALIA Research Group.Department of Physical Metallurgy Centro Nacional de Investigaciones Metalúrgicas (CENIM-CSIC)Avda.Gregorio del Amo 8.E-28040MadridSpain CEIT and TECNUM (University of Navarra) Po Manuel de Lardizabal 15San SebastianE-20018Basque ContrySpain

Nowadays there is a continuous demand,particularly from the automotive industry,for cheaper,lighter and more reliable *** is not surprising then that steel research has been focused during the last decades in new qualities and *** paper is dealing with the use of vanadium microalloyed steels on one of those new processes,warm *** its low precipitation temperature and its recognised ability to strengthen steel microstructures via austenite grain growth control,precipitation hardening and interference of the static recrystallization process,vanadium in microalloyed steels seem to be an appropriate candidate for warm forging.

关键词： warm forging vanadium microalloyed steels

In vitro antioxidant,antilipoxygenase and antimicrobial activities of extracts from seven climbing plants belonging to the Bignoniaceae

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Journal of Integrative Medicine 2018年第4期16卷 255-262页

作者： Carola analla Torres Cristina Marisel Perez Zamora Maria beatriz Nunez ana Maria Gonzalez Laboratory of Microbiology and Pharmaceutical Technology Department of Basic and Applied SciencesNational University of Chaco AustralPresidencia Roque Saenz Pena 3700ChacoArgentina National Council for Scientific and Technical Research(CONICET) Godoy Cruz 2290Buenos Aires C1425FQBArgentina Institute of Botany of the Northeast(IBONE-CONICET) Sargento Juan Bautista Cabral 2131CorrientesArgentina

Objectives： This study aimed to evaluate the in vitro antioxidant capacity, to determine the anti-inflammatory effect due to lipoxygenase inhibition and to test the antimicrobial activity of ethanolic extracts from leaves of seven climbing species belonging to the Bignoniaceae family. These species are Adenocalyrnrna rnarginatum （Cham.） DC., Amphilophium vauthieri DC., Cuspidaria convoluta （VEIL） A. H. Gentry, Dolichandra dentata （K. Schum.） L. G. Lohmann, Fridericia caudigera （S. Moore） L. G. Lohmann, Fridericia chica （Bonpl.） L. G. Lohmann and Tanaecium selloi （Spreng.） L. G. Lohmann. Methods： The antioxidant activity was evaluated using three methods, 2,2＇-azino-bis（3-ethylbenzothiazo line-6-sulfonic acid）（ABTS）, 2,2-diphenyl-l-picrylhydrazyl （DPPH）, and ferric reducing antioxidant power. Lipoxygenase-inhibiting activity was assayed spectrophotometrically; the result was expressed as percent inhibition. The antimicrobial activity was assessed using the agar disk diffusion method. Minimal inhibitory concentration （MIC） and minimal bactericidal]fungicidal concentration were also determined for each extract against 12 pathogenic bacterial strains of Staphylococcus aureus and seven fungal strains of the Candida genus. The identification of the major compounds present in the most promising extract was established by high-performance liquid chromatography-tandem mass spectrometry. Results： C convoluta, F. caudigera, and F. chica exhibited the best antioxidant activity by scavenging DPPH and ABTS~ radicals and reducing Fe3＋ ion. These extracts showed a notable inhibition of lipnxygenase. F. caudigera was found to have the lower MIC value against S. aureus strains and six Candida species. The extracts of F. caudigera and C. convoluta were active even against methicillin-resistant S. aureus. C convoluta had higher total phenol content, better antioxidant activity and superior anti- inflammatory and antimicrobial activity. The main phenolic compounds found in this extract

关键词： Cuspidaria Fridericia Antioxidants Lipoxygenase Antimicrobials Herbal drugs Free radical scavengers

Ontogeny of vocal rhythms in harbor seal pups: an exploratory study

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Current Zoology 2019年第1期65卷 107-120页

作者： Andrea RAViGNANi Christopher T. Kello Koen de Reus Sonja A KoTz Simone Dalla BELLA Margarita Mendez-Arostegui beatriz Rapado-Tamarit ana Rubio-garcia Bart de BoER Research Department Sealcentre Pieterburen Pieterburen The Netherlands Artificial Intelligenee Lab Vrije Universiteit Brussel Brussels Belgium Cognitive and Information Sciences University of California Merced CA USA Basic and Applied NeuroDynamics Lab Faculty of Psychology and Neuroscience Department of Neuropsychology & Psychopharmacology Maastricht University Maastricht The Netherlands Department of Neuropsychology Max-Planck Institute for Human Cognitive and Brain Sciences Leipzig Germany International Laboratory for Brain Music and Sound Research (BRAMS) Montreal QC Canada Department of Psychology University of Montreal Montreal QC Canada Department of Cognitive Psychology WSFiZ in Warsaw Warsaw Poland

Puppyhood is a very active social and vocal period in a harbor seal's life Ph oca vitulina. An important feature of vocalizations is their temporal and rhythmic structure, and understanding vocal timing and rhythms in harbor seals is critical to a cross-species hypothesis in evolutionary neuroscience that links vocal learning, rhythm perception, and synchronization. This study utilized analytical techniques that may best capture rhythmic structure in pup vocalizations with the goal of examining whether (1) harbor seal pups show rhythmic structure in their calls and (2) rhythms evolve over time. Calls of 3 wild-born seal pups were recorded daily over the course of 1-3 weeks;3 temporal features were analyzed using 3 complementary techniques. We identified temporal and rhythmic structure in pup calls across different time windows. The calls of harbor seal pups exhibit some degree of temporal and rhythmic organization, which evolves over puppyhood and resembles that of other species' in teractive comm un icati on. We suggest n ext steps for investigating call structure in harbor seal pups and propose comparative hypotheses to test in other pinniped species.

关键词： bioacoustics pinnipeds rhythm timing vocal development

Li2SnO3 branched nano- and microstructures with intense and broadband white-light emission

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Nano Research 2019年第2期12卷 441-448页

作者： Miguel garcia-Tecedor Javier Bartolome David Maestre Achim Trampert ana Cremades Dpt. Fisica de Materials Facultad de CC. Fisicas Universidad Complutense de Madrid Madrid 28040 Spain Paul-Drude-Institut fur Festkorperelektronik Hausvogteiplatz 5-7 Berlin 10117 Germany Institute of Advanced Materials (INAM) Universitat Jaume I Castello 12006 Spain Dpt. Fisica de Materiales Facultad de CC. Ftsicas Universidad Complutense de Madrid Madrid 28040 Spain

Exploiting the synergy between microstructure, morphology and dimensions by suitable nanomaterial engineeri ng, can effectively upgrade the physical properties and material performances. Li2SnO3 elongated nano- and microstructures in form of belts, wires, rods and branched structures have been fabricated by a vapor-solid method at temperatures ranging from 700 to 900℃ using metallic Sn and Li2CO3 as precursors. The achievement of these new morphologies can face challenging applications for Li2SnO3, not only in the field of energy storage, but also as building blocks in optoelectronic devices. The micro? and nanostructures grown at 700 and 800℃ correspond to monoclinic Li2SnO3, while at 900℃ complex Li2S nO/SnO2 core-shell microstructures are grow n, as con firmed by X-ray diffractio n and Rama n spectroscopy. Transmission electron microscopy reveals structural disorder related to stacking faults in some of the branched structures, which is associated with the prese nee of the low-temperature phase of L12S nO3. The luminescent resp onse of these structures is domi nated by in tense emissi ons at 2, 2.5 and 3 eV, almost completely covering the whole range of the visible light spectrum. As a result, white-light emission is obtained without the need of phosphors or complex quantum well heterostructures. Enhanced functionality in applications such as in light-emitting devices could be exploited based on the high luminescenee intensity observed in some of the analysed Li2SnO3 structures.

关键词： lithium oxides white light emitters nanostructures luminescenee