30 research outputs found

    The Ph1

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    ZIP4 is required for normal progression of synapsis and for over 95% of crossovers in wheat meiosis

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    Tetraploid (AABB) and hexaploid (AABBDD) wheat have multiple sets of similar chromosomes, with successful meiosis and preservation of fertility relying on synapsis and crossover (CO) formation only taking place between homologous chromosomes. In hexaploid wheat, the major meiotic gene TaZIP4-B2 (Ph1) on chromosome 5B, promotes CO formation between homologous chromosomes, whilst suppressing COs between homeologous (related) chromosomes. In other species, ZIP4 mutations eliminate approximately 85% of COs, consistent with loss of the class I CO pathway. Tetraploid wheat has three ZIP4 copies: TtZIP4-A1 on chromosome 3A, TtZIP4-B1 on 3B and TtZIP4-B2 on 5B. Here, we have developed single, double and triple zip4 TILLING mutants and a CRISPR Ttzip4-B2 mutant, to determine the effect of ZIP4 genes on synapsis and CO formation in the tetraploid wheat cultivar ‘Kronos’. We show that disruption of two ZIP4 gene copies in Ttzip4-A1B1 double mutants, results in a 76-78% reduction in COs when compared to wild-type plants. Moreover, when all three copies are disrupted in Ttzip4-A1B1B2 triple mutants, COs are reduced by over 95%, suggesting that the TtZIP4-B2 copy may also affect class II COs. If this is the case, the class I and class II CO pathways may be interlinked in wheat. When ZIP4 duplicated and diverged from chromosome 3B on wheat polyploidization, the new 5B copy, TaZIP4-B2, could have acquired an additional function to stabilize both CO pathways. In tetraploid plants deficient in all three ZIP4 copies, synapsis is delayed and does not complete, consistent with our previous studies in hexaploid wheat, when a similar delay in synapsis was observed in a 59.3 Mb deletion mutant, ph1b, encompassing the TaZIP4-B2 gene on chromosome 5B. These findings confirm the requirement of ZIP4-B2 for efficient synapsis, and suggest that TtZIP4 genes have a stronger effect on synapsis than previously described in Arabidopsis and rice. Thus, ZIP4-B2 in wheat accounts for the two major phenotypes reported for Ph1, promotion of homologous synapsis and suppression of homeologous COs

    Use of interactive response devices for the improvement of teaching in the degrees of the Faculty of Sciences

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    La implantaciĂłn de los nuevos Grados dentro del EEES supone un nuevo enfoque metodolĂłgico, pero sobre todo evaluador. El profesor debe esforzarse en ser capaz de valorar no sĂłlo el nivel de conocimientos del alumnado sobre los contenidos, ya que la sociedad actual demanda un perfil de los egresados mĂĄs completo basado en la formaciĂłn por competencias. La adquisiciĂłn de ambas facetas por parte del alumnado se basa principalmente en actividades presenciales y metodologĂ­as docentes aplicadas en el desarrollo de las asignaturas, tanto en grupo reducido como en grupo completo. Por tanto, cualquier herramienta adicional que ayude al docente a facilitar esta doble tarea es bien recibida, pues permitirĂĄ evaluar el rendimiento acadĂ©mico global del alumnado. Recientemente la Facultad de Ciencias ha puesto en marcha una experiencia piloto mediante la cual un nutrido grupo de profesores ha incorporado en su docencia un sistema de mandos inalĂĄmbricos de respuesta. Actualmente, la Facultad de Ciencias dispone de un total de 82 mandos inalĂĄmbricos de respuesta y tres antenas receptoras. Esta nueva tecnologĂ­a ha permitido al docente realizar, de forma interactiva, preguntas colectivas al alumnado y recoger las respuestas individuales de forma inmediata. Los resultados obtenidos en este proyecto nos permiten ser muy optimistas con el uso de esta herramienta y nos animan a continuar en la misma lĂ­nea. El profesorado participante se ha mostrado dispuesto a continuar empleando esta TIC en su docencia, tratando de abarcar mĂĄs asignaturas, diversificar el tipo de pruebas, y emplear los mandos de respuesta en grupo completo, cuando el nĂșmero de alumnos lo permita. La puesta en comĂșn de los resultados revela que, de forma general, este tipo de sistemas de respuesta incrementa el nivel de atenciĂłn del alumnado, ya que se les demanda de forma continuada su participaciĂłn activa durante la sesiĂłn. Se potencia la retenciĂłn de conceptos, al suministrar en el acto la respuesta correcta a cada pregunta realizada. Permite tambiĂ©n al profesorado conocer el nivel previo de conocimientos sobre la materia a impartir, ya que se puede realizar este tipo de preguntas al comienzo de la sesiĂłn y enfocar entonces su atenciĂłn en las debilidades manifestadas. Asimismo se puede testar el grado de adquisiciĂłn de dichos conocimientos, realizando este tipo de cuestionarios despuĂ©s de la sesiĂłn. AdemĂĄs, el tratamiento posterior de los resultados, de forma individualizada, permite gestionar de forma ĂĄgil el nivel de conocimientos y adquisiciĂłn de competencias en lo que es un sistema de evaluaciĂłn continua, tan necesario en los nuevos enfoques metodolĂłgicos nacidos de la implantaciĂłn del EEES. Por Ășltimo destacar que el profesorado participante ha considerado que se trata de una herramienta de gran utilidad para la consecuciĂłn del objetivo de excelencia en la docencia, que ademĂĄs es eficaz y de fĂĄcil manejo, y entiende que no debe ser una actividad puntual, sino un proceso transformador en la actividad docente e interacciĂłn alumno-profesor, configurĂĄndose como una herramienta habitual en los sistemas de enseñanza-aprendizaje.Implementation of the new degrees in the EHEA involve a new methodological approach, but above all evaluation. The teacher should strive to be able to assess not only the level of knowledge of the students on the content, as the current society demands a profile of the most complete graduates based on training by competencies. The acquisition of both facets by students is based mainly on face-to-face activities and teaching methodologies applied in the development of the subjects, both in small group and in whole group. Therefore, any additional tool that helps the teacher to facilitate this double task is well received, since it will allow to evaluate the overall academic performance of the students. Recently the Faculty of Sciences has launched a pilot experience through which a large group of teachers has incorporated into their teaching a system of interactive response devices. Currently, the Faculty of Sciences has a total of 82 wireless response controllers and three receiving antennas. This new technology has enabled the teacher to interact interactively with the students and collect the individual answers immediately. The results obtained in this project allow us to be very optimistic with the use of this tool and encourage us to continue in the same line. The participating teachers have been willing to continue using this ICT in their teaching, trying to cover more subjects, diversify the type of tests, and use the full group response commands, when the number of students allows. The sharing of results reveals that, in a general way, this type of response systems increases the level of attention of the students, since they are continuously demanded their active participation during the session. The retention of concepts is strengthened by providing the correct answer to every question asked. It also allows the faculty to know the previous level of knowledge about the subject to be taught, since this type of questions can be asked at the beginning of the session and then focus their attention on the weaknesses manifested. It is also possible to test the degree of acquisition of this knowledge, performing this type of questionnaire after the session. In addition, the subsequent treatment of the results, in an individualized way, allows to manage in an agile way the level of knowledge and acquisition of competences in what is a system of continuous evaluation, so necessary in the new methodological approaches born from the implantation of the EHEA. Finally, it should be pointed out that the participating teachers have considered that this is a very useful tool for achieving the objective of excellence in teaching, which is also efficient and easy to use and understands that it should not be a specific activity, but a transforming process in the teaching activity and student-teacher interaction, being configured as a habitual tool in the teaching-learning systems

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Identification and comparison of individual chromosomes of three Hordeum chilense accessions, Hordeum vulgare and Triticum aestivum by FISH

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    Karyotypes of three accessions of Hordeum chilense (H1, H16 and H7), Hordeum vulgare and Triticum aestivum were characterized by physical mapping of several repetitive sequences. A total of fourteen repetitive sequences were used as probes for fluorescence in situ hybridization (FISH) with the aim of identifying inter- and intra-species polymorphisms. The (AG)12 and 4P6 probes only produced hybridization signals in wheat, the BAC7 probe only hybridized to the centromeric region of H. vulgare, and the pSc119.2 probe hybridized to both wheat and H. chilense, but not to H. vulgare. The remaining repetitive sequences used in this study produced a hybridization signal in all the genotypes. Probes pAs1, pTa535, pTa71, CCS1 and CRW were much conserved, showing no significant polymorphism among the genotypes studied. Probes GAA, (AAC)5, (CTA)5, HvT01 and pTa794 produced the most different hybridization pattern. We identified large polymorphisms in the three accessions of H. chilense studied, supporting the proposal of the existence of different groups inside H. chilense species. The set of probes described in this work allowed the identification of every single chromosome in all three species, providing a complete cytogenetic karyotype of H. chilense, H. vulgare and T. aestivum chromosomes, useful in wheat and tritordeum breeding programs.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

    Different genomic combinations involving 1H<sup><i>ch</i></sup>S and 6H<sup><i>ch</i></sup>S chromosomes arms obtained in this work.

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    <p>n: chromosome number; Conf: chromosome configuration; St ab: standard abbreviation.</p><p>Different genomic combinations involving 1H<sup><i>ch</i></sup>S and 6H<sup><i>ch</i></sup>S chromosomes arms obtained in this work.</p
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