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Ni-based catalysts obtained from perovskites oxides for ethanol steam reforming

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燃料化学学报 2018年第11期46卷 1332-1341页

作者： fabiola Nerina Agüero jose Antonio Alonso Maria Teresa fernández-Díaz luis Eduardo Cadus Instituto de Investigaciones en Tecnología Química(INTEQUI) UNSL-CONICETAlmirante Brown 14555700 San LuisArgentina Instituto de Ciencia de Materiales de Madrid Consejo Superior de Investigaciones CientíficasCantoblanco28049 MadridSpain Institut Laue-Langevin B.P.156F-38042 Grenoble Cedex 9France

Perovskites as host structures of cations were used in order to generate in situ active and stable catalysts for ethanol steam reforming. for this purpose,La_(1-x)Mg_xAl_(1-y)Ni_yO_3(x = 0.1; y = 0,0.1,0.2,0.3) perovskites were synthetized by the citrate *** segregation is evident for a substitution level higher than 0. 2. The segregation of Ni as NiO generated species interacts with different metal-support after the reduction step. The y = 0.1 catalyst presents the highest H_2 yield value about 85% during reaction time,with low mean values of CH_4 and CO selectivities of 3.4% and 11%,respectively and a low carbon formation. The better performance of y = 0.1 catalyst could be attributed to the minor proportion of segregated phases,thus a controlled expulsion of Ni is successfully reached.

关键词： perovskites catalyst design ethanol steam reforming

Phenotyping for Abiotic Stress Tolerance in Maize

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Journal of Integrative Plant Biology 2012年第4期54卷 238-249页

作者： Benhilda Masuka jose luis Araus Biswanath Das Kai Sonder Jill E.Cairns International Maize and Wheat Improvement Center(CIMMYT) Unit of Plant Physiology Faculty of BiologyUniversity of Barcelona CIMMYT Km 45 Carretera Mexico-Veracruz

The ability to quickly develop germplasm having tolerance to several complex polygenic inherited abiotic and biotic stresses combined is critical to the resilience of cropping systems in the face of climate change. Molecular breeding offers the tools to accelerate cereal breeding; however, suitable phenotyping proto- cols are essential to ensure that the much-anticipated benefits of molecular breeding can be realized. To facilitate the full potential of molecular tools, greater emphasis needs to be given to reducing the within-experimental site variability, application of stress and characterization of the environment and appropriate phenotyping tools. Yield is a function of many processes throughout the plantcycle, and thus integrative traits that encompass crop performance over time or organization level （i.e. canopy level） will provide a better alternative to instantaneous measurements which provide only a snapshot of a given plant process. Many new phenotyping tools based on remote sensing are now available including non-destructive measurements of growth-related parameters based on spectral reflectance and infrared thermometry to estimate plant water status. Here we describe key field phenotyping protocols for maize with emphasis on tolerance to drought and low nitrogen.

关键词： Drought low nitrogen tolerance maize phenotyping spatial variability.

Changes in Cinnamic Acid Derivatives Associated with the Habituation of Maize Cells to Dichlobenil

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Molecular Plant 2011年第5期4卷 869-878页

作者： Hugo Melida Jesus Alvarez jose luis Acebes Antonio Encina Stephen C. fry Area de fisiologia Vegetal Facultad de CC Biologicas y Ambientales Universidad de Leon E-24071 Leon Spain Edinburgh Cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences University of Edinburgh Daniel Rutherford Building The King＇s Buildings Edinburgh EH9 3JH UK

The habituation of cell cultures to cellulose biosynthesis inhibitors such as dichlobenil （DCB） represents a valu- able tool to improve our knowledge of the mechanisms involved in plant cell wall structural plasticity. Maize cell lines habituated to lethal concentrations of DCB were able to grow through the acquisition of a modified cell wall in which cellulose was partially replaced by a more extensive network of arabinoxylans. The aim of this work was to investigate the phenolic metabolism of non-habituated and DCB-habituated maize cell cultures. Maize cell cultures were fed [14C]cinnamate and the fate of the radioactivity in different intra-protoplasmic and wall-localized fractions throughout the culture cycle was analyzed by autoradiography and scintillation counting. Non-habituated and habituated cultures did not markedly differ in their ability to uptake exogenous [14C]cinnamic acid. However, interesting differences were found in the radiolabeling of low- and high-Mr metabolites. Habituated cultures displayed a higher number and amount of radiola-beled low-Mr compounds, which could act as reserves later used for polysaccharide feruloylation. DCB-habituated cultures were highly enriched in esterified [14C]dehydrodiferulates and larger coupling products. In conclusion, an extensive and early cross-linking of hydroxycinnamates was observed in DCB-habituated cultures, probably strengthening their cellulose-deficient walls.

关键词： Cell wall Zea mays maize dichlobenil DCB dehydrodiferulate ferulate cinnamic acid.

New Technologies,Tools and Approaches for Improving Crop Breeding

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Journal of Integrative Plant Biology 2012年第4期54卷 210-214页

作者： Parry, Martin A. J. Wang, Jiankang luis Araus, jose Rothamsted Res Harpenden Herts England Chinese Acad Agr Sci Beijing 100193 Peoples R China Univ Barcelona Barcelona Spain

Most crops were first domesticated about 13 000 to 11 000 years ago. Humans are dependent on crops for survival, and from the beginnings of agriculture have been energetically involved in developing crops that better serve their needs （Allard 1999）. During the last decades breeding has contributed approximately a 50% contribution to increasing the world＇s food crop production. However, plant breeding only began to adopt a scientific approach in the 1900s, when Mendel＇s hybridization experiment was rediscovered. Mendelian genetics and the development of the statistical concepts of randomJzatJon and replication had considerable impact on plant breeding methods （Hallauer et al. 1988）. In spite of the fact that scientific crop breeding has only existed for one century, it is a discipline that is developing very quickly. The major objective of crop breeding programs is to develop new genotypes that are genetically superior to those currently available for specific environments. To achieve this objective, breeders employ a range of selection methods and technologies （Hallauer et al. 1988; falconer and Mackay 1996; Allard 1999）.

关键词： New Technologies Tools Approaches Improving Crop Breeding

Prevalence and risk factors of acute-on-chronic liver failure in a single center from Argentina

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World Journal of Hepatology 2016年第34期8卷 1529-1534页

作者： Cristian Dominguez Eugenia Romero Jorgelina Graciano jose luis fernandez luis Viola Division of Gastroenterology Sanatorio Guemes Centro Integral de Gastroenterología

AIMTo study the prevalence, characteristics, risk factors and mortality at 28 d of acute-on-chronic liver failure (ACLf). METHODSA total of 100 cirrhotic patients admitted to our hospital for more than one day were included during the period between June 2013 and December 2015. We used the European Association for the Study of the Liver-Chronic Liver failure-Consortium diagnostic criteria for ACLf, considering it as the acute decompensation of cirrhosis associated with the presence of one or more organ failure. for the diagnosis of organic failure the Chronic Liver failure-Sequential Organ failure Assessment score was used. Our population was divided into patients with and without ACLf. Clinical characteristics, presence of precipitating events, potential risk factors for developing ACLf and causes of mortality were analyzed. Mortality at 28 d was evaluated. RESULTSTwenty-nine patients (29%) developed ACLf criteria. Alcoholism, detected in 58 patients (58%), was the major etiological agent of cirrhosis. Bacterial infections were recognized as a precipitating event in 41.3% of cases and gastrointestinal bleeding in 27.5%. No precipitating event was identifiable in 27.5% of patients with ACLf. Comparing patients with and without ACLf, statistically significant risk factors were: Child Pugh score 10.2 ± 2.1 vs 8.4 ± 1.6 (P ˂ 0.0001), MELD score 20.7 ± 8.5 vs 12.3 ± 4 (P ˂ 0.0001), presence of ascites 27 (93%) vs 43 (60.5%) (P = 0.001), leukocytosis 15300 ± 8033 per cubic millimeter vs 10770 ± 5601 per cubic millimeter (P ˂ 0.0001), and high plasma levels of C reactive protein values 50.9 ± 46.4 mg/L vs 28.6 ± 23.4 mg/L (P ˂ 0.0019). Mortality rate was 62% (18 patients) vs 5.6% (4 patients), respectively (P CONCLUSIONWe observed that the ACLf is a frequent entity in this group of patients and has a significantly higher mortality rate.

关键词： Acute-on-chronic liver failure Acute liver decompensation Cirrhosis Ascites Mortality

Gene expression and physiological responses to salinity and water stress of contrasting durum wheat genotypes

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Journal of Integrative Plant Biology 2016年第1期58卷 48-66页

作者： Salima Yousfi Antonio J.Marquez Marco Betti jose luis Araus Maria Dolores Serret Unit of Plant Physiology Department of Plant BiologyFaculty of BiologyUniversity of Barcelona08028Spain Department of Plant Biochemistry and Molecular Biology Faculty of ChemistryUniversity of SevilleSevilla 41012Spain

Elucidating the relationships between gene expression and the physiological mechanisms remains a bottleneck in breeding for resistance to salinity and drought. This study related the expression of key target genes with the physiological performance of durum wheat under different combinations of salinity and irrigation. The candidate genes assayed included two encoding for the DREB（dehydration responsive element binding） transcription factors Ta DREB1 A and Ta DREB2 B, another two for the cytosolic and plastidic glutamine synthetase（Ta GS1 and Ta GS2）, and one for the specific Na^＋/H^＋ vacuolar antiporter（Ta NHX1）. Expression of these genes was related to growth and different trait indicators of nitrogen metabolism（nitrogen content, stable nitrogen isotope composition, and glutamine synthetase and nitrate reductase activities）, photosynthetic carbon metabolism（stable carbon isotope composition and different gas exchange traits） and ion accumulation. Significant interaction between genotype and growing conditions occurred for growth, nitrogen content, and the expression of most *** general terms, higher expression of Ta GS1, Ta GS2,Ta DREB2 B, and to a lesser extent of Ta NHX1 were associated with a better genotypic performance in growth, nitrogen, and carbon photosynthetic metabolism under salinity and water stress. However, Ta DREB1 A was increased in expression under stress compared with control conditions, with tolerant genotypes exhibiting lower expression than susceptible ones.

关键词： Durum wheat (Triticum turgidum ssp. durum) geneexpression nitrogen metabolism salinity stable isotope

Dissecting Maize Productivity:Ideotypes Associated with Grain Yield under Drought Stress and Well-watered Conditions

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Journal of Integrative Plant Biology 2012年第12期54卷 1007-1020页

作者： Jill E.Cairns Ciro Sanchez Mateo Vargas Raziel Ordoez jose luis Araus Global Maize Program International Maize and Wheat Improvement Center(CIMMYT)Mexico D.F.Mexico Bioinformatics and Statistics Unit International Maize and Wheat Improvement Center(CIMMYT)Mexico D.F.Mexico Unit of Plant Physiology Department of Plant BiologyUniversity of BarcelonaBarcelonaSpain

To increase maize （Zea mays L.） yields in drought-prone environments and offset predicted maize yield losses under future climates, the development of improved breeding pipelines using a multi-disciplinary approach is essential. Elucidating key growth processes will provide opportunities to improve drought breeding progress through the identification of key phenotypic traits, ideotypes, and donors. In this study, we tested a large set of tropical and subtropical maize inbreds and single cross hybrids under reproductive stage drought stress and well-watered conditions. Patterns of biomass production, senescence, and plant water status were measured throughout the crop cycle. Under drought stress, early biomass production prior to anthesis was important for inbred yield, while delayed senescence was important for hybrid yield. Under well-watered conditions, the ability to maintain a high biomass throughout the growing cycle was crucial for inbred yield, while a stay-green pattern was important for hybrid yield. While new quantitative phenotyping tools such as spectral reflectance （Normalized Difference Vegetation Index, NDVI） allowed for the characterization of growth and senescence patterns as well as yield, qualitative measurements of canopy senescence were also found to be associated with grain yield.

关键词： Climate change drought stress ideotypes maize senescence spectral reflectance.

The interplay of nurse and target plant traits influences magnitude and direction of facilitative interactions under different combinations of stress and disturbance intensities in Andean dry grassland

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Journal of Plant Ecology 2016年第3期9卷 296-310页

作者： Andrea Catorci Luca Malatesta jose luis Velasquez federico Maria Tardella Horacio Zeballos School of Biosciences and Veterinary Medicine University of Camerinovia Pontoni 5CamerinoMCItaly School of Advanced Studies PhD Course in Environmental Sciences and Public Health University of Camerinovia Lili 55CamerinoMCItaly Centro de Estudios y Promoción del Desarrollo(Desco) Málaga Grenet 678ArequipaPeru Instituto de Ciencias de la Naturaleza Territorio Yenergia RenovablesPontificia Universidad Católica del Perù.Av.Universitaria 1801San Miguel 32LimaPerù

Aims facilitation is a key process in vegetation dynamics,driving the response to natural and anthropogenic *** harsh-grazed systems,palatable plants mainly survive when nested under unpalatable tussocks and *** magnitude and direction of positive interactions are driven by resource availability,extent of herbivory and type of nurse *** hypothesized that different combinations of disturbance and environmental stress affect community composition in the dry Puna(southern Peruvian Andes)by modifying nurse types and plant interactions in magnitude and specific *** investigated whether different combinations of stress and disturbance influence species richness,type and frequency of occurrence of nurse and beneficiary species and magnitude and patterns of plant interactions;whether nurse species influence these interactions and target species change their interactions under different combinations of stress and disturbance and whether plant functional traits differ in the studied communities and influence the pattern of spatial *** We selected three plant communities subject to different precipitation and management regimes:in each we laid a number of transects proportional to its *** collected include species presence/absence,type of spatial interactions with nurse species and functional *** calculated species richness and rarefaction patterns,described the patterns of plant-plant spatial interactions and investigated the associations between nurse and other species in the three communities using indicator species analysis(ISA).We performed ISA and correlation analysis to investigate whether plant functional traits influenced facilitative *** findings We found that different combinations of stress and disturbance shaped a complex set of responses,including changes in the nurse species *** composition influenced magnitude and direction of plant interactions under different stress

关键词： dry Puna facilitation functional traits nurse and beneficiary species species-specific interaction stress-gradient hypothesis

Water-soluble hollow nanocrystals from self-assembly of AIEEactive Pt(II)metallomesogens

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Nano Research 2021年第1期14卷 245-254页

作者： Cristian Cuerva Javier fernandez-Lodeiro Mercedes Cano jose luis Capelo-Martinez Carlos Lodeiro BIOSCOPE Research Group LAQV@REQUIMTE Chemistry DepartmentNOVA School of Science and TechnologyNOVA University Lisbon2829-516 CaparicaPortugal PROTEOMASS Scientific Society Rua dos InventoresMadam ParqueCaparica Campus2829-516 CaparicaPortugal Department of Inorganic Chemistry Complutense University of MadridCiudad Universitaria28040 MadridSpain

Luminescent hollow micro-and nanocrystals have been successfully obtained taking advantage of the self-assembly behavior and the aggregation-induced emission enhancement properties of several bispyrazolate Pt(II)metallomesogens decorated with four terminal alkyl ***-in-water droplets have been used to confine the Pt(II)compounds and drive them to be self-assembled via intermolecular Pt…Pt interactions into spherical aggregates of about 200 or 50 *** of the oil phase generates highly-stable aqueous dispersions of nanocrystals that emit a bright orange light as a result of the existence of^(3)MMLCT excited *** methods and conditions have been tested for studying the effect of several parameters such as the temperature and the stirring speed in the final particle size and in the polydispersity ***,the micro-and nanocrystals are able to entrap hydrophobic drugs between the alkyl chains of the compounds,forming stable dispersions of drug-loaded capsules in *** droplet method is applied in the area of metallomesogens for the first time to synthesize self-assembled Pt(II)nanocapsules,which opens a new field of study that could allow the use of these liquid crystal materials in biomedical applications.

关键词： R(II)metallomesogens self-assembly luminescent nanomaterials droplets nanocapsules