291 research outputs found
Molecular role of Pelota (PELO) in differentiation of embryonic and germ stem cells
Pelo ist ein evolutionĂ€r konserviertes Gen, das in diversen Spezies charakterisiert wurde. In der Maus fĂŒhrt der Verlust von Pelo zu embryonaler LetalitĂ€t in frĂŒhen Postimplantationsstadien. In vitro Studien mit Pelo-null Blastocysten haben gezeigt, dass PELO möglicherweise eine Rolle bei der Regulation des Zellzyklus oder der Selbsterneuerung der pluripotenten Embryonaler Stammzellen (Embryonic Stem Cells, ESCs) spielt. In der vorliegenden Arbeit sollte die molekulare Rolle von PELO bei der Selbsterneuerung und bei der Differenzierung von ESCs und Keimbahnstammzellen mit Hilfe eines konditionalen Pelo Knockout-Mausmodels in Kombination mit in vitro sowie in vivo Experimenten untersucht werden.
Im ersten Teil der Arbeit konnten wir zeigen, dass PELO fĂŒr die Selbsterneuerung von ESCs oder deren Differenzierung in die drei KeimblĂ€tter nicht notwendig ist, jedoch unabdingbar ist fĂŒr die Differenzierung des extraembryonalen Endoderms (ExEn). Im Umkehrschluss wird durch die Ăberexpression von Pelo in ESCs das Programm zur Differenzierung des ExEn`s aktiviert. Auf molekularer Ebene konnten wir zeigen, dass die beeintrĂ€chtigte Differenzierung des ExEn`s in Pelo-defizienten Embryoidkörpern (Embryonic Bodies, EBs) aus einer reduzierten AktivitĂ€t des Bone Morphogenetic Proteins (BMP) resultiert. Dieses Ergebnis wurde durch weitere Experimente bestĂ€tigt, die gezeigt haben, dass Pelo-defiziente Zellen durch Behandlung mit BMP4 in das ExEn differenzieren können. In vivo Studien haben gezeigt, dass Pelo-null Embryonen am Tag 6.5 (E6.5) das ExEn besitzen, jedoch an E7.5 versterben. Dies lĂ€sst vermuten, dass PELO nicht fĂŒr die Induktion der Entwicklung des ExEn`s notwendig ist, sondern vielmehr fĂŒr dessen Erhaltung oder abschlieĂende Differenzierung in das funktionelle viszerale Endoderm, das den Embryo mit Wachstumsfaktoren fĂŒr die weitere Entwicklung versorgt. Zudem ist PELO notwendig fĂŒr die BMP-Aktivierung zu Beginn der somatischen Zellreprogrammierung. Der Verlust von PELO beeintrĂ€chtigt die Reprogrammierung zur induzierten Pluripotenz. AuĂerdem konnten wir die konservierte Funktion von PELO im QualitĂ€tskontrollmechanismus der RNA in murinen ESCs feststellen.
Im zweiten Teil der Arbeit haben wir demonstriert, dass die Pelo-Expression essentiell fĂŒr die Erhaltung der mĂ€nnlichen FertilitĂ€t und Spermatogenese ist. Der Verlust von Pelo wĂ€hrend der Entwicklung von mĂ€nnlichen Keimzellen in MĂ€usen hat gezeigt, dass PELO fĂŒr die Selbsterneuerung und Erhaltung der Spermatogonialen Stammzellen (Spermatogonial Stem Cells, SSCs) notwendig ist, jedoch fĂŒr die Entwicklung der spĂ€teren Spermatogenesestadien sowie die Spermienfunktion erlĂ€sslich ist.
Insgesamt zeigen unsere Studien die molekulare Rolle(n) von PELO in der frĂŒhen Embryonalentwicklung der Maus und bei der mĂ€nnlichen FertilitĂ€t auf. Unsere Ergebnisse geben Hinweise auf Ursachen von Defekten, die mit dem PELO Verlust zusammenhĂ€ngen
Adaptation and Assessment (TwoA) asset in C# (v1.2)
RAGE products are licensed under the Apache License, Version 2.0 (the "License"). See the License for the specific language governing permissions and limitations under the License: http://www.apache.org/licenses/LICENSE-2.0Developed within the RAGE project funded by EU within Horizon2020 program. This asset enables a real-time automatic adaptation of game difficulty to player's expertise level. The adaptation algorithm makes use of a stealth assessment algorithm that assigns difficulty ratings and expertise ratings to the players and the game modules respectively. The asset tracks changes in these ratings allowing assessment of players' learning progress either by players themselves or by instructors. This is the version written in C# language.This study is part of the RAGE project. The RAGE project has received funding from the European Unionâs Horizon 2020 research and innovation programme under grant agreement No 644187. This publication reflects only the author's view. The European Commission is not responsible for any use that may be made of the information it contains
Adaptation and Assessment (TwoA) asset in TypeScript (v1.0)
RAGE products are licensed under the Apache License, Version 2.0 (the "License"). See the License for the specific language governing permissions and limitations under the License: http://www.apache.org/licenses/LICENSE-2.0Developed within the RAGE project funded by EU within Horizon2020 program. This asset enables a real-time automatic adaptation of game difficulty to player's expertise level. The adaptation algorithm makes use of a stealth assessment algorithm that assigns difficulty ratings and expertise ratings to the players and the game modules respectively. The asset tracks changes in these ratings allowing assessment of players' learning progress either by players themselves or by instructors. This is the version written in TypeScript language.This study is part of the RAGE project. The RAGE project has received funding from the European Unionâs Horizon 2020 research and innovation programme under grant agreement No 644187. This publication reflects only the author's view. The European Commission is not responsible for any use that may be made of the information it contains
A Study for the Development Needs of Professional Teachers at Vocational Education and Training Institution in Mongolia
This paper describes an importance of development needs of professional teachers at vocational education and training institutions in Mongolia. Study group consisted of 14 public and private vocational education institutions and 285 professional teachers participated in the survey. The purpose of this study was to determine the needs of teacher training and professional development at vocational education and training institutions. In particular, the relationship between the needs of teachers and the factors that influence them have been analyzed within the framework of the survey. For statistical analyses, variation value, reliability analysis, KMO and Bartlettâs test, commonality of variables, correlation analysis were performed. The findings indicated that it is necessary to implement various policies and activities to support and develop school-based activities and support them financially in order to ensure the professional development of teachers. Also, it is required to consider the teacher development of training content and improvement of training courses to support the development of teachers of vocational education and training. Moreover, there is need to operate the content of training for teacher development. The paper concludes with recommendations for further investigation
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