2,326 research outputs found
Establishing a Markerless Genetic Exchange System for Methanosarcina mazei Strain Gö1 for Constructing Chromosomal Mutants of Small RNA Genes
A markerless genetic exchange system was successfully established in Methanosarcina mazei strain Gö1 using the hpt gene coding for hypoxanthine phosphoribosyltransferase. First, a chromosomal deletion mutant of the hpt gene was generated conferring resistance to the purine analog 8-aza-2,6-diaminopurine (8-ADP). The nonreplicating allelic exchange vector (pRS345) carrying the pac-resistance cassette for direct selection of chromosomal integration, and the hpt gene for counterselection was introduced into this strain. By a pop-in and ultimately pop-out event of the plasmid from the chromosome, allelic exchange is enabled. Using this system, we successfully generated a M. mazei deletion mutant of the gene encoding the regulatory non-coding RNA sRNA154. Characterizing M. mazeiÎsRNA154 under nitrogen limiting conditions demonstrated differential expression of at least three cytoplasmic proteins and reduced growth strongly arguing for a prominent role of sRNA154 in regulation of nitrogen fixation by posttranscriptional regulation
Die Struktur der Cosa Nostra-Mafia im Italienischunterricht â Interkulturelles und nachhaltigkeitssensibilisierendes Potenzial eines Erinnerungsortes
Dieser Beitrag befasst sich mit der Frage, wie die Strukturen der Cosa Nostra-Mafia im Italienischunterricht der gymnasialen Oberstufe behandelt werden können. Das Potenzial der Mafia als zentraler Erinnerungsort (luogo della memoria) der italienischen Kultur soll im Rahmen eines kompetenzorientierten Italienischunterrichts anhand einer Stunde exemplifiziert werden â eingebettet in eine Unterrichtsreihe zum Thema âSicilia - Mafia e lotta alla mafiaâ. Neben Unterrichtsmaterialien (Fachtexte von ausgewiesenen Mafiaexperten) zur pyramidalen und konzentrischen Struktur der Cosa Nostra werden pre- while and after reading activities zur Förderung der Lesekompetenz vorgestellt sowie ein Stundenverlaufsplan angeboten. Eine Reflexion der durchgefĂŒhrten Stunde sowie des Potentials dieses Erinnerungsortes im Kontext einer Bildung fĂŒr nachhaltige Entwicklung (BNE) schlieĂt den Beitrag ab
Evolutionary models predict potential mechanisms of escape from mutational meltdown
Mutagenic drugs are promising candidates for the treatment of various RNA virus infections. Increasing the mutation rate of the virus leads to rapid accumulation of deleterious mutation load, which is proposed to ultimately result in extinction as described by the theoretical concepts of mutational meltdown and lethal mutagenesis. However, the conditions and potential mechanisms of viral escape from the effects of mutagenic drugs have not been conceptually explored. Here we apply a computational approach to quantify the population dynamics and genetics of a population under high mutation rates and discuss the likelihood of adaptation to a mutagenic drug by means of three proposed mechanisms: (1) a proportion of âtraditionalâ beneficial mutations that increase growth/fitness, (2) a mutation rate modifier (i.e., evolution of resistance to the mutagenic drug) that reduces the mutation rate, and (3) a modifier of the distribution of fitness effects, which either decreases or increases deleterious effects of mutations (i.e., evolution of tolerance to the mutagenic drug). We track the population dynamics and genetics of evolving populations and find that successful adaptations have to appear early to override the increasing mutational load and rescue the population from its imminent extinction. We highlight that the observed stochasticity of adaptation, especially by means of modifiers of the distribution of fitness effects, is difficult to capture in experimental trials, which may leave potential dangers of the use of mutagenic treatments unexposed
UnStumm | Augmented Voyage: A Platform for Telematic Live Performances in Augmented Reality
UnStumm | Augmented Voyage is curated and developed by time-based media artist Claudia Schmitz and sound artist and guitarist Nicola L. Hein. It was programmed and developed by software engineer Sven Hahne. UnStumm | Augmented Voyage is also a mobile app and server infrastructure that serves as the artistic vehicle to realize telematic live performances with artists from around the globe. It consists of video art, music, and dance in augmented reality.
Through the use of our software, the audience is able to view the video streams by video artists as 3D video sculptures and listen to the audio streams by the musicians through a virtual, multi-channel loudspeaker system. In the following text, we discuss the technical development, artistic aims, and realization of UnStumm | Augmented Voyage; we additionally present several projects that have already been realized with it
The extinction time under mutational meltdown driven by high mutation rates.
Mutational meltdown describes an eco-evolutionary process in which the accumulation of deleterious mutations causes a fitness decline that eventually leads to the extinction of a population. Possible applications of this concept include medical treatment of RNA virus infections based on mutagenic drugs that increase the mutation rate of the pathogen. To determine the usefulness and expected success of such an antiviral treatment, estimates of the expected time to mutational meltdown are necessary. Here, we compute the extinction time of a population under high mutation rates, using both analytical approaches and stochastic simulations. Extinction is the result of three consecutive processes: (a) initial accumulation of deleterious mutations due to the increased mutation pressure; (b) consecutive loss of the fittest haplotype due to Muller's ratchet; (c) rapid population decline toward extinction. We find accurate analytical results for the mean extinction time, which show that the deleterious mutation rate has the strongest effect on the extinction time. We confirm that intermediate-sized deleterious selection coefficients minimize the extinction time. Finally, our simulations show that the variation in extinction time, given a set of parameters, is surprisingly small
Marcas da educa??o rural e desafios da educa??o do campo em Guatambu-SC
This study evidences the process of rural school nucleation in the municipality of GuatambuSC, seeking also to reflect about the unfolding of the action on the citizens and the strengthening of the school transport policy that has been historically implanted with great adherence in all Brazilian territory. The methodological perspective of the research adopted is a documentary and bibliographical analysis, supported by dialogues with/among literary areas that approach subjects such as countryside education, rural education, pedagogical methodologies of teaching in the countryside, school transport policy and the nucleation process. In addition, the work also seeks to highlight important facts of countryside education, based on a dialogue with a former resident, aiming the development aspects that marked a period in the history of the municipality. Thus, the work is about the Rural Education marks and the struggling with it, evidencing that the nuclearization of school attendance occurred in Guatambu-SC, first, by a policy induced by the Education State Department of Santa Catarina, emerging a School transportation network. Finally, Countryside Education is pointed as a possible way to overcome thenegative sides of this movement.Este trabalho evidencia pontos que constitu?ram o processo de nuclea??o das escolas rurais no munic?pio de Guatambu-SC, buscando refletir, tamb?m, acerca dos desdobramentos dessa a??o sobre os mun?cipes e o fortalecimento da pol?tica de transporte escolar que veio sendo historicamente implantada com muita ader?ncia em todo territ?rio brasileiro. A perspectiva metodol?gica de pesquisa adotada neste trabalho ? a an?lise documental e bibliogr?fica, sustentada por meio de di?logos com/entre obras liter?rias que abordam temas como a educa??o do campo, a educa??o rural, metodologias pedag?gicas de ensino com os sujeitos do campo, pol?tica de transporte escolar e o processo de nuclea??o. Al?m disso, buscamos destacar marcos hist?ricos da Educa??o do Campo, a partir do di?logo com um antigo morador, objetivando levantar aspectos que marcaram um per?odo da hist?ria do munic?pio. Dessa forma, tratamos das marcas da Educa??o Rural e as lutas pela sua supera??o, evidenciando que a nucleariza??o do atendimento escolar ocorreu em Guatambu-SC, inicialmente, por indu??o de uma pol?tica da Secretaria de Estado da Educa??o de Santa Catarina, fazendo emergir uma rede de transporte escolar. Por fim, apontamos a Educa??o do Campo como caminho poss?vel para supera??o de efeitos negativos desse movimento
Regulation of mating in the budding yeast Saccharomyces cerevisiae by the zinc cluster proteins Sut1 and Sut2
This article is made available through the Brunel Open Access Publishing Fund. Copyright @ The Authors. This is an open-access article distributed under the terms of the Creative
Commons Attribution License, which permits unrestricted use, distribution, and
reproduction in any medium, provided the original author and source are credited.The zinc cluster proteins Sut1 and Sut2 play a role in sterol uptake and filamentous growth in the budding yeast Saccharomyces cerevisiae. In this study, we show that they are also involved in mating. Cells that lack both SUT1 and SUT2 were defective in mating. The expression of the genes NCE102 and PRR2 was increased in the sut1 sut2 double deletion mutant suggesting that Sut1 and Sut2 both repress the expression of NCE102 and PRR2. Consistent with these data, overexpression of either SUT1 or SUT2 led to lower expression of NCE102 and PRR2. Furthermore, expression levels of NCE102, PRR2 and RHO5, another target gene of Sut1 and Sut2, decreased in response to pheromone. Prr2 has been identified as a mating inhibitor before. Here we show that overexpression of NCE102 and RHO5 also reduced mating. Our results suggest that Sut1 and Sut2 positively regulate mating by repressing the expression of the mating inhibitors NCE102, PRR2 and RHO5 in response to pheromone.Deutsche Forschungsgemeinschaf
Extended Art-of-Living Coaching: An Integrative Approach to Changing Strategies and Overcoming Barriers
Die Forschung zu einem individuellen Lebenskunst-Coaching ist zwar noch in den AnfĂ€ngen, aber erste Ergebnisse geben vielversprechende Hinweise darauf, dass Lebenskunst durch Coaching gefördert werden kann (Stumpp-Spies/Schmitz 2017b). Hierbei sind die Ressourcen und die Strategien der Coachees ein wichtiger Ausgangspunkt, von dem aus ein Coaching konzipiert werden kann. DarĂŒber hinaus könnten aber noch andere Faktoren eine Rolle dabei spielen, ob ein Coachee seine Lebenskunst verbessern kann oder nicht. Die vorliegende Arbeit geht von der Vermutung aus, dass mögliche Hindernisse wie z.âŻB. Perfektionismus, ĂŒberzogene Erwartungen oder Entscheidungen eine Rolle dabei spielen könnten, wenn Coachees bestimmte Strategien nicht umsetzen können. Die Frage ist also: Warum können bestimmte Ressourcen zuweilen nicht in gute Strategien umgesetzt werden und woran liegt das? Zu diesem Zweck wurden von einem Coach mit 20 ProbandInnen in einer Experimentalgruppe qualitative Interviews durchgefĂŒhrt, die wörtlich transkribiert und dann qualitativ ausgewertet wurden. Diejenigen Hindernisse, von denen sich die ProbandInnen sehr stark oder stark betroffen fĂŒhlten, wurden in den Coaching-Prozess miteinbezogen. Spezifische Interventionen zielten darauf ab, auf diese Hindernisse einzuwirken und sie abzuschwĂ€chen. Durch einen Mixed-Methods-Ansatz wurde Lebenskunst mittels einer Kombination aus qualitativen und quantitativen Verfahren umfassend abgebildet und ein Erkenntnisgewinn erzielt, den man mit einem rein quantitativen Verfahren nicht hĂ€tte erreichen können. Die Ergebnisse zeigen, dass Hindernisse bei den teilnehmenden ProbandInnen eine Rolle spielten und dass diese sich durch spezifische Interventionen abschwĂ€chen lieĂen.Research examining the coaching of individuals concerning their art-of-living is still in the early stages. However, there are promising findings indicating that art-of-living can be improved through coaching (Stumpp-Spies/Schmitz 2017b). Coacheesâ resources and strategies influence the potential success of a coaching intervention and, thus, should form the starting point for the specific conceptualization thereof. In addition, other factors may also play a role in whether coachees successfully improve their art-of-living. The current study therefore assumes that possible barriers - such as perfectionism, exaggerated expectations, and specific decisions - potentially affect whether coachees are able to implement certain strategies. Thus, we address the following question: Why can certain resources sometimes not be translated into good strategies? With this question in mind, a coach conducted qualitative interviews with 20 participants of the experimental group. The interviews were then transcribed verbatim and examined using qualitative methods. For each participant, the barriers reported to have a strong or very strong effect on the respective person were addressed in the coaching process. Specific interventions then aimed at minimizing the effect of those barriers on the respective participant. Using a mixed-method approach, we assessed participantsâ art-of-living using a combination of qualitative and quantitative measures. In doing so, we obtained findings that would not have been possible using quantitative methods alone. Our results indicate that barriers play a role in participantsâ art-of-living. This effect was successfully weakened by the coaching intervention
Age-Related Differences in the Luminal and Mucosa-Associated Gut Microbiome of Broiler Chickens and Shifts Associated with Campylobacter jejuni Infection
Investigation of hippocampal synaptic transmission and plasticity in mice deficient in the actin-binding protein Drebrin
The dynamic regulation of the actin cytoskeleton plays a key role in controlling the structure and function of synapses. It is vital for activity-dependent modulation of synaptic transmission and long-term changes in synaptic morphology associated with memory consolidation. Several regulators of actin dynamics at the synapse have been identified, of which a salient one is the postsynaptic actin stabilising protein Drebrin (DBN). It has been suggested that DBN modulates neurotransmission and changes in dendritic spine morphology associated with synaptic plasticity. Given that a decrease in DBN levels is correlated with cognitive deficits associated with ageing and dementia, it was hypothesised that DBN protein abundance instructs the integrity and function of synapses. We created a novel DBN deficient mouse line. Analysis of gross brain and neuronal morphology revealed no phenotype in the absence of DBN. Electrophysiological recordings in acute hippocampal slices and primary hippocampal neuronal cultures showed that basal synaptic transmission, and both long-term and homeostatic synaptic plasticity were unchanged, suggesting that loss of DBN is not sufficient in inducing synapse dysfunction. We propose that the overall lack of changes in synaptic function and plasticity in DBN deficient mice may indicate robust compensatory mechanisms that safeguard cytoskeleton dynamics at the synapse
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