Ángel Vázquez Alonso

First llama (Lama glama) pregnancy obtained after in vitro fertilization and in vitro culture of gametes from live animals

The aim of this study was to evaluate the developmental competence and pregnancy rate of llama hatched blastocysts produced in vitro using gametes from live animals and two different culture conditions. Fifteen adult females were superstimulated with 1500 IU of eCG, eleven (73%) responded to the treatment and were used as oocyte donors. Follicular aspiration was conducted by flank laparotomy. Semen collections were performed under general anesthesia by electroejaculation of the male. Sixty-six COCs were recovered from 77 aspirated follicles (86% recovery) and were randomly placed in Fertil-TALP microdroplets with the sperm suspension (20 × 10(6)live spermatozoa/ml). After 24 h, they were placed in SOFaa medium supplemented with FCS and randomly assigned to one of two culture conditions. Culture condition 1 (CC1) consisted of 6 days of culture (n=28) and culture condition 2 (CC2) consisted of renewing the culture medium every 48 h (n=35). In CC1, the blastocyst rate was 36% (10/28) and the hatched blastocyst rate was 28% (8/28) whereas in CC2, the blastocyst rate was 34% (12/35) and the hatched blastocyst rate was 20% (7/35) (p>0.05). No pregnancies were obtained after embryo transfer (ET) of CC1 blastocysts (0/8) while one pregnancy was obtained (1/7) after transferring a hatched blastocyst from CC2. Forty-two days after the ET, the pregnancy was lost. This study represents the first report of a pregnancy in the llama after intrauterine transfer of embryos produced by in vitro fertilization using gametes from live animals.

El efecto de un programa de formación para profesores sobre sus concepciones de naturaleza de la ciencia y tecnología

The themes of nature of science and technology (NoST further, the changes for each of the ten assessment questions are identified, which reveal the complexity of conceptual change. Finally, feasibility, generalization and improvements proposed for the initial training model for science teachers is discussed.

La selección de contenidos para enseñar naturaleza de la ciencia y tecnología (parte 2): Una revisión aplicada a los currículos de ciencias españoles

Este estudio revisa los curriculos de ciencias espanoles y la competencia cientifica de PISA como fuente de contenidos de aprendizaje correspondientes a la “naturaleza de la ciencia” (y tecnologia) como continuacion de una primera parte que expuso los hallazgos de la investigacion. El proposito es construir un marco de referencia que ilumine, contextualice y clarifique el sentido global de la ensenanza de la naturaleza de la ciencia a la luz de las propuestas de los curriculos de ciencias espanoles actuales. Primero, se presentan las contribuciones de algunos curriculos extranjeros para identificar los contenidos consensuados. Segundo, se presenta la perspectiva y aportaciones de la competencia cientifica, desde los marcos de referencia de PISA y la competencia sobre conocimiento e interaccion con el mundo fisico. Tercero, se identifican los contenidos para la ensenanza de la naturaleza de la ciencia (y tecnologia) presentes en el curriculo espanol de la educacion secundaria y el bachillerato y se analiza su diseno, organizacion y sentido en el marco curricular. Finalmente, se discuten las fortalezas y debilidades del marco curricular y se diagnostican las dificultades de la didactica de estas cuestiones innovadoras, de modo que se pongan las bases que motiven, conciencien y ayuden al profesorado a superar las dificultades. Normal 0 21 false false false MicrosoftInternetExplorer4