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High post-anthesis temperature effects on 3 bread wheat (Triticum aestivum L.) grain 4 transcriptome during early grain-filling
Background: High post-anthesis (p.a) temperatures reduce mature grain weights in wheat and other cereals.
However, the causes of this reduction are not entirely known. Control of grain expansion by the maternally derived pericarp of the grain has previously been suggested, although this interaction has not been investigated under high p.a. temperatures. Down-regulation of pericarp localised genes that regulate cell wall expansion under high p.a. temperatures may limit expansion of the encapsulated endosperm due to a loss of plasticity in the pericarp,reducing mature grain weight. Here the effect of high p.a. temperatures on the transcriptome of the pericarp and endosperm of the wheat grain during early grain-filling was investigated via RNA-Seq and is discussed alongside grain moisture dynamics during early grain development and mature grain weight.
Results: High p.a. temperatures applied from 6-days after anthesis (daa) and until 18daa reduced the grain’s ability to accumulate water, with total grain moisture and percentage grain moisture content being significantly reduced from 14daa onwards. Mature grain weight was also significantly reduced by the same high p.a. temperatures
applied from 6daa for 4-days or more, in a separate experiment. Comparison of our RNA-Seq data from whole
grains, with existing data sets from isolated pericarp and endosperm tissues enabled the identification of subsets of genes whose expression was significantly affected by high p.a. temperature and predominantly expressed in either tissue. Hierarchical clustering and gene ontology analysis resulted in the identification of a number of genes implicated in the regulation of cell wall expansion, predominantly expressed in the pericarp and significantly down26 regulated under high p.a. temperatures, including endoglucanase, xyloglucan endotransglycosylases and a β27 expansin. An over-representation of genes involved in the ‘cuticle development’ functional pathway that were
expressed in the pericarp and affected by high p.a. temperatures was also observed.
Conclusions: High p.a. temperature induced down-regulation of genes involved in regulating pericarp cell wall expansion. This concomitant down-regulation with a reduction in total grain moisture content and grain weight following the same treatment period, adds support to the theory that high p.a. temperatures may cause a
reduction in mature grain weight as result of decreased pericarp cell wall expansion
The Krzyż conjecture revisited
The Krzyz conjecture concerns the largest values of the Taylor coefficients of a non-vanishing analytic function bounded by one in modulus in the unit disk. It has been open since 1968 even though information on the structure of extremal functions is available. The purpose of this paper is to collect various conditions that the coefficients of an extremal function (and various other quantities associated with it) should satisfy if the conjecture is true and to show that each one of these properties is equivalent to the conjecture itself. This may provide several possible starting points for future attempts at solving the problemThe first, third and fourth authors thankfully acknowledge partial support from MINECO grant MTM2012-37436-C02-02, Spain. Starting in 2014 the first author was supported by Academy of Finland grant 268009. The second author was supported by NSERC, Canada. The third author was also supported by NSF grant DMS-0901524, by NSF CAREER, Award No. DMS-1056965, and Sloan Research Fellowship, USA. The fourth author was partially supported by the European ESF Network HCAA (“Harmonic and Complex Analysis and Its Applications”) during
the period November 2009 - April 201
A Deep Double Ritz Method (D2RM) for solving Partial Differential Equations using Neural Networks
Residual minimization is a widely used technique for solving Partial Differential Equations in variational form. It minimizes the dual norm of the residual, which naturally yields a saddle-point (min–max) problem over the so-called trial and test spaces. In the context of neural networks, we can address this min–max approach by employing one network to seek the trial minimum, while another network seeks the test maximizers. However, the resulting method is numerically unstable as we approach the trial solution. To overcome this, we reformulate the residual minimization as an equivalent minimization of a Ritz functional fed by optimal test functions computed from another Ritz functional minimization. We call the resulting scheme the Deep Double Ritz Method (DRM), which combines two neural networks for approximating trial functions and optimal test functions along a nested double Ritz minimization strategy. Numerical results on different diffusion and convection problems support the robustness of our method, up to the approximation properties of the networks and the training capacity of the optimizers
Phylogenetic analyses of typical bovine rotavirus genotypes G6, G10, P[5] and P[11] circulating in Argentinean beef and dairy herds
Group A rotavirus (RVA) is one of the main causes of neonatal calf diarrhea worldwide. RVA strains affecting Argentinean cattle mainly possess combinations of the G6, G10, P[5] and P[11] genotypes. To determine RVA diversity among Argentinean cattle, representative bovine RVA strains detected in diarrheic calves were selected from a survey conducted during 1997–2009. The survey covered the main livestock regions of the country from dairy and beef herds. Different phylogenetic approaches were used to investigate the genetic evolution of RVA strains belonging to the prevalent genotypes. The nucleotide phylogenetic tree showed that all genotypes studied could be divided into several lineages. Argentinean bovine RVA strains were distributed across multiple lineages and most of them were distinct from the lineage containing the vaccine strains. Only the aminoacid phylogenetic tree of G6 RVA strains maintained the same lineages as observed at the nucleotide level, whereas a different clustering pattern was observed for the aminoacid phylogenetic trees of G10, P[5] and P[11] suggesting that the strains are more closely related at the aminoacid level than G6 strains. Association between P[5] and G6(IV), prevalent in beef herd, and between P[11] and G6(III) or G10 (VI and V), prevalent in dairy herds, were found. In addition, Argentinean G6(III), G10, P[5] and P[11] bovine RVA strains grouped together with human strains, highlighting their potential for zoonotic transmission. Phylogenetic studies of RVA circulating in animals raised for consumption and in close contact with humans, such as cattle, contribute to a better understanding of the epidemiology of the RVA infection and evolution.Fil: Badaracco, Alejandra. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garaicoechea, Lorena Laura. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Matthijnssens, J.. University of Leuven. Rega Institute for Medical Research; BélgicaFil: Louge Uriarte, Enrique Leopoldo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Odeón, Anselmo Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce. Área de Investigación en Producción y Sanidad Animal; ArgentinaFil: Bilbao, Gladys Noemí. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias; ArgentinaFil: Fernandez, Fernando. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Parra, G. I.. National Institutes of Health; Estados UnidosFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Centre de Formentera: els inicis en qüestió de dependència
Fins ara l’atenció i els serveis sociosanitaris específics per a la tercera edat i els malalts crònics han estat gairebé inexistents a Formentera; el tipus d’assistència que s’ha donat ha estat majoritàriament d’ajuda o de suport mitjançant el curador informal. És un fet que els trets particulars que presenta Formentera plantegen unes necessitats especials; així, cal un esforç per aconseguir una equiparació en les prestacions i els serveis existents a la resta d’illes. La construcció d’un centre de dia suposa un pas important per superar aquesta mancança de recursos, i alhora és un projecte necessari i esperat a l’illa. Segons les dades demogràfiques, la de Formentera serà una població envellida; aquest centre garantirà a la població una millor qualitat d’atenció i de vida, donant resposta i cobertura a les necessitats de les persones dependents, amb serveis que, d’altra banda, són de primera necessitat. Aquest projecte suposa un repte tant institucional com professional. Les característiques de Formentera fan que el centre estigui plantejat per donar assistència als tres col·lectius més vulnerables i desprotegits: persones grans dependents, persones amb algun tipus de discapacitat i persones amb malaltia mental; d’aquesta manera ens trobam davant tres centres dins una mateixa instal·lació. Així, el Programa Bàsic del Centre s’inscriu dins una estratègia institucional dirigida a oferir un marc terapèutic que faciliti confiança i seguretat a l’usuari i que mitjançant el suport i l’ensenyament permeti treballar les capacitats conservades, millorant l’autonomia i alentint el procés de dependència. Cal destacar la novetat del recurs per als habitants de Formentera, juntament amb un factor cultural molt arrelat a l’illa, que estableix la cura de les persones grans a casa i sota la figura d’algun familiar. Malgrat això, les actuals previsions indiquen un debilitament d’aquesta xarxa de cures, circumstància que ve provocada per diversos factors: el canvi en el rol social de la dona, l’envelliment i augment de la fragilitat dels cuidadors, així com l’estrès del cuidador / la cuidadora, habitualment generat per una situació de cures llarga i intensa —i sovint difícil— en absència d’un suport adequat.Hasta ahora la atención y los servicios sociosanitarios específicos para la tercera edad y los enfermos crónicos han sido casi inexistentes en Formentera; el tipo de asistencia dirigida ha sido mayoritariamente de ayuda o apoyo mediante el cuidador informal. Es un hecho que las particulares condiciones que presenta la isla plantean unas necesidades especiales, así hace falta un esfuerzo para conseguir una equiparación en las prestaciones y servicios existentes en el resto de islas y donde la construcción de un centro de día en Formentera supone un paso importante para superar la carencia de recursos o estructuras sociosanitarias. Este Centro de día es un proyecto necesario y esperado en la isla, que prevé paliar el déficit sociosanitario existente hasta ahora. Según los datos demográficos, Formentera, en un futuro, será una población envejecida; este centro garantizará a la población una mejor calidad de atención y de vida, dando respuesta y cobertura a las necesidades de las persones dependientes con servicios que, por otro lado, son de primera necesidad. La puesta en marcha de este proyecto supone un reto tanto a nivel institucional como profesional. Las características de Formentera (tamaño, población, aislamiento, etc.), hacen que el proyecto de centro de día esté planteado para dar asistencia a los tres colectivos más vulnerables y desprotegidos: personas mayores dependientes, personas con algún tipo de discapacidad y personas con enfermedad mental, de este modo nos encontramos ante tres centros de día dentro de una misma instalación. Así, el Programa Básico del Centro se inscribe dentro de una estrategia institucional dirigida a ofrecer un marco terapéutico que facilite confianza y seguridad al usuario y que, a través del apoyo y la enseñanza, permita trabajar sobre las capacidades conservadas mejorando la autonomía y ralentizando el proceso de dependencia. También se tiene que destacar la novedad del recurso para los habitantes de la isla y un factor cultural muy arraigado en la población de Formentera que establece el cuidado de los mayores en casa y bajo la figura de algún familiar. Sin embargo, las actuales previsiones indican un debilitamiento de esta red de apoyo, circunstancia que viene provocada por varios factores: el cambio en el rol social de la mujer, el envejecimiento y aumento de la fragilidad de los cuidadores, así como el estrés del cuidador/a habitualmente generado por una situación de curas larga e intensa —y a menudo difícil— en ausencia de un apoyo adecuado
GeneSrF and varSelRF: a web-based tool and R package for gene selection and classification using random forest
<p>Abstract</p> <p>Background</p> <p>Microarray data are often used for patient classification and gene selection. An appropriate tool for end users and biomedical researchers should combine user friendliness with statistical rigor, including carefully avoiding selection biases and allowing analysis of multiple solutions, together with access to additional functional information of selected genes. Methodologically, such a tool would be of greater use if it incorporates state-of-the-art computational approaches and makes source code available.</p> <p>Results</p> <p>We have developed GeneSrF, a web-based tool, and varSelRF, an R package, that implement, in the context of patient classification, a validated method for selecting very small sets of genes while preserving classification accuracy. Computation is parallelized, allowing to take advantage of multicore CPUs and clusters of workstations. Output includes bootstrapped estimates of prediction error rate, and assessments of the stability of the solutions. Clickable tables link to additional information for each gene (GO terms, PubMed citations, KEGG pathways), and output can be sent to PaLS for examination of PubMed references, GO terms, KEGG and and Reactome pathways characteristic of sets of genes selected for class prediction. The full source code is available, allowing to extend the software. The web-based application is available from <url>http://genesrf2.bioinfo.cnio.es</url>. All source code is available from Bioinformatics.org or The Launchpad. The R package is also available from CRAN.</p> <p>Conclusion</p> <p>varSelRF and GeneSrF implement a validated method for gene selection including bootstrap estimates of classification error rate. They are valuable tools for applied biomedical researchers, specially for exploratory work with microarray data. Because of the underlying technology used (combination of parallelization with web-based application) they are also of methodological interest to bioinformaticians and biostatisticians.</p
La luz, un sabor inolvidable
La iluminación natural es un parámetro de diseño, el cual permite configurar diferentes ambientes interiores con bajo consumo energético. Actividades con una vista-lateral son muy comunes. Es una de las más antiguas aplicaciones de iluminación por su facilidad, practicismo y apertura accesible. Frecuentemente, esta entrada de luz esta proporcionada por la fachada y está complementada por la vista exterior. A este tipo de vista se le puede denominar vista-lateral.Postprint (published version
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