32 research outputs found
Fission yeast Cactin restricts telomere transcription and elongation by controlling Rap1 levels
No full textThe telomeric transcriptome comprises multiple long non-coding RNAs generated by transcription of linear chromosome ends. In a screening performed in Schizosaccharomyces pombe, we identified factors modulating the cellular levels of the telomeric transcriptome. Among these factors, Cay1 is the fission yeast member of the conserved family of Cactins, uncharacterized proteins crucial for cell growth and survival. In cay1∆ mutants, the cellular levels of the telomeric factor Rap1 are drastically diminished due to defects in rap1+ pre-mRNA splicing and Rap1 protein stability. cay1∆ cells accumulate histone H3 acetylated at lysine 9 at telomeres, which become transcriptionally desilenced, are over-elongated by telomerase and cause chromosomal aberrations in the cold. Overexpressing Rap1 in cay1+ deleted cells significantly reverts all telomeric defects. Additionally, cay1∆ mutants accumulate unprocessed Tf2 retrotransposon RNA through Rap1-independent mechanisms. Thus, Cay1 plays crucial roles in cells by ultimately harmonizing expression of transcripts originating from seemingly unrelated genomic loci
Factors influencing credibility perceptions of AI journalism: Investigating attitudes, trust in news media, and perceived agency
No full textThis bachelor thesis addresses factors influencing the perceived credibility of AI-generated articles in journalism. Specifically, the influence of media trust, agency, the machine heuristic, and the author on perceived (message) credibility will be investigated
Does polarizing news become less polarizing when written by an AI?
No full textIn this study, we examine how readers perceive the credibility of polarizing news purportedly written by a machine. In particular, we study whether a machine attribution can decrease the polarization inflicted by the self-confirmation bias. To that end, we expect that attitude-confirming polarizing news is perceived as less credible when attributed to a machine than when attributed to a human author. We assume this is due to the lower source credibility of machines and less emotional involvement. In a preregistered online experiment, we presented N = 508 participants with a polarizing news article attributed either to a human author or a machine. The article also either confirmed or disconfirmed participants’ attitudes towards the polarizing issue. Our results show that participants did not differentiate between human and machine-attributed news. Moreover, we found no evidence that machine-attributed news affected the self-confirmation bias. However, we found that, while machine authors were perceived equally competent as human authors, they were perceived as less trustworthy. In addition, we found that the machine attribution induced less emotional involvement in terms of experienced enthusiasm but not experienced anger
The telomeric transcriptome of Schizosaccharomyces pombe
No full textISSN:1362-4962, 0301-5610ISSN:0301-561
Managing processes and information technology in mergers - the integration of finance processes and systems
No full textMany companies use mergers to achieve their growth goals or target technology position. To realise synergies that justify the merger transaction, an integration of the merged companies is often necessary. Such integartion takes place across company business areas (such as finance or sales) and across the layers of management consideration, which are strategy, human resources, organisation, processes, and information technology.
In merger integration techniques, there is a significant gap regarding the management of operational level issues. Yet, especially for the finance business area, an integration of processes and information technology is of high importance and often required swiftly after the merger. The author therefore presents an approach designed for managing the operational level merger in the finance business area.
To close the gap in considering operational level issues, the author has developed a model for integraring finance processes and information technology of merging companies. For such model development, literature resources have been used along with merger experiences of the author, and interviews with merger experts. Validation of the developed model has been conducted by using in-depth case studies for showing the effects of applying the model. Further validation interviews have been conducted to support the generality of the approach.
Accommodating the significant increase of task complexity during mergers compared to normal business operation, the presented approach focuses on managing interdependencies instead of project detail. Features of this approach comprise:
An organisational proposal to settinmg up merger programme management;
An interdependency model, vertically interconnecting the finance business area with strategic and organisational merger decisions, and horizontally interconnecting the finance business area with other business areas.
It could be shown that the presented model improves merger integration quality by reducing complexity of merger management. The model is most applicable for larger companies, and can be used in any merger phase
TRF1 participates in chromosome end protection by averting TRF2-dependent telomeric R loops
No full textThe telomeric transcriptome of Schizosaccharomyces pombe
No full textEukaryotic telomeres are transcribed into telomeric repeat-containing RNA (TERRA). Telomeric transcription has been documented in mammals, birds, zebra fish, plants and budding yeast. Here we show that the chromosome ends of Schizosaccharomyces pombe produce distinct RNA species. As with budding yeast and mammals, S. pombe contains G-rich TERRA molecules and subtelomeric RNA species transcribed in the opposite direction of TERRA (ARRET). Moreover, fission yeast chromosome ends produce two novel RNA species: C-rich telomeric repeat-containing transcripts (ARIA) and subtelomeric transcripts complementary to ARRET (αARRET). RNA polymerase II (RNAPII) associates with pombe chromosome ends in vivo and the telomeric factor Rap1 negatively regulates this association, as well as the cellular accumulation of RNA emanating from chromosome ends. We also show that the RNAPII subunit Rpb7 and the non-canonical poly(A) polymerases Cid12 and Cid14 are involved in the regulation of TERRA, ARIA, ARRET and αARRET transcripts. We confirm the evolutionary conservation of telomere transcription, and reveal intriguing similarities and differences in the composition and regulation of telomeric transcripts among model organism
Towards the microscopic understanding of self-healing mechanisms
No full textIn the present work we report on a Random Phase Approximation (RPA) which can be applied to multiblock copolymers consisting of supramolecular building blocks and hydrogen-bonded compounds including interactions in solution. These systems are model for the self-healing process due to the hydrogen-bonding interaction between the end-groups. This new analysis allowed to quantitatively access the assembly route with varying concentration
Quantitative reconstruction of precipitation changes on the NE Tibetan Plateau since the Last Glacial Maximum – extending the concept of pollen source area to pollen-based climate reconstructions from large lakes
No full textPollen records from large lakes have been used for quantitative
palaeoclimate reconstruction, but the influences that lake size (as a result
of species-specific variations in pollen dispersal patterns that smaller
pollen grains are more easily transported to lake centre) and taphonomy have
on these climatic signals have not previously been systematically
investigated. We introduce the concept of pollen source area to pollen-based
climate calibration using the north-eastern Tibetan
Plateau as our study area. We present a pollen data set collected from large
lakes in the arid to semi-arid region of central Asia. The influences that
lake size and the inferred pollen source areas have on pollen compositions
have been investigated through comparisons with pollen assemblages in
neighbouring lakes of various sizes. Modern pollen samples collected from
different parts of Lake Donggi Cona (in the north-eastern part of the
Tibetan Plateau) reveal variations in pollen assemblages within this large
lake, which are interpreted in terms of the species-specific dispersal and
depositional patterns for different types of pollen, and in terms of fluvial
input components. We have estimated the pollen source area for each lake
individually and used this information to infer modern climate data with
which to then develop a modern calibration data set, using both the
multivariate regression tree (MRT) and weighted-averaging partial least
squares (WA-PLS) approaches. Fossil pollen data from Lake Donggi Cona have
been used to reconstruct the climate history of the north-eastern part of
the Tibetan Plateau since the Last Glacial Maximum (LGM). The mean annual
precipitation was quantitatively reconstructed using WA-PLS: extremely dry
conditions are found to have dominated the LGM, with annual precipitation of
around 100 mm, which is only 32% of present-day precipitation. A
gradually increasing trend in moisture conditions during the Late Glacial is
terminated by an abrupt reversion to a dry phase that lasts for about 1000 yr
and coincides with "Heinrich event 1" in the North Atlantic
region. Subsequent periods corresponding to the Bølling/Allerød
interstadial, with annual precipitation (Pann) of about 350 mm, and the
Younger Dryas event (about 270 mm Pann) are followed by moist
conditions in the early Holocene, with annual precipitation of up to 400 mm.
A drier trend after 9 cal. ka BP is followed by a second wet phase in the
middle Holocene, lasting until 4.5 cal. ka BP. Relatively steady conditions
with only slight fluctuations then dominate the late Holocene, resulting in
the present climatic conditions. The climate changes since the LGM have been
primarily driven by deglaciation and fluctuations in the intensity of the
Asian summer monsoon that resulted from changes in the Northern Hemisphere
summer solar insolation, as well as from changes in the North Atlantic
climate through variations in the circulation patterns and intensity of the
westerlies
Synthesis and Analysis of Transient-Covalent Double Networks
No full textNature uses a combination of dynamic hydrogen bonds and static covalent bonds in e.g. the muscle sarcomer to achieve toughness in otherwise elastic materials. The dynamic bonds can open when a force is applied, thereby providing a stress-relieve mechanism to prevent rupturing of the covalent links. Upon release of external force the hydrogen bond network can heal to restore the former properties. To mimic these astonishing effects we envisioned a similar combination in elastomeric compounds by creating a dual network of hydrogen bonded and covalently linked polyisoprene. We synthesized a number of dual networks by first modifying polyisoprene with hydrogen bond forming urazole groups to form supramolecular networks with a cross-linking density between 0 and 15 mol%. In a second step covalent crosslinks were added by hydrosilylation with a bissilane linker. Linear rheological analysis of the transient network showed a dissipation mechanism extrapolated to be on the order of 0.01 - 0.10 s at ambient temperature. In combination with neutron scattering, which provides unrivalled and first insights on the chain level, the self-healing properties of these novel semi-transient networks are studied on the molecular level in static and dynamic deformation through a selective labelling of chains. Understanding of the self-healing mechanism in these mixed covalent and transient systems will allow the development of new polymeric materials with advanced functionality
