1,061 research outputs found
Resetting Cell Fate by Epigenetic Reprogramming
Epigenetic modifications and their regulations govern the identity of every cell type in an organism. Cell differentiation involves a switch in gene expression profile that is accompanied by heritable changes of epigenetic signatures in the differentiated cell type. Differentiation is generally not reversible, thereby conferring cell fate decisions once an altered epigenetic pattern is set. Nevertheless, attempts have been made to reverse a differentiation cell fate to a pluripotent state by various experimental approaches, such as somatic cell nuclear transfer, cell fusion and ectopic expression of defined transcription factors. The fundamental basis of all these strategies is to mediate epigenetic reprogramming, which allows a permanent and completed conversion of cell fate. A comprehensive understanding of the dynamic of epigenetic changes during cell differentiation would provide a more precise and efficient way of reprogramming cell fate. Here we summarize the epigenetic aspects of different reprogramming strategies and discuss the possible mechanisms underlying these epigenetic reprogramming events
An Evaluation of the World-Views for the Grab-and-Glue Framework
Creating simulation models based on the world-views such as the three-phase approach, the event-based approach, the activity-based approach and the processbased approach has been used as a standard practice for several decades. However, it is still not known whether they are suitable to be adopted or not when creating a simulation model by following the Grab-and-Glue framework. Hence, this paper aims at evaluating the suitability of accessing these world-views when building a simulation model based on the Grab-and-Glue framework. After an evaluation is conducted based on the proposed criteria, it is discovered that none of the world-views are suitable to be used. Hence, it is recommended that a new world-view is necessary to be developed for structuring the simulation model which is assembled based on the Grab-and-Glue framework
Explorations of an intramolecular route to pyrrolo[3,4-b]isoxazoles: an unexpected retro-Claisen reaction
Potential precursors have been prepared for intramolecular 1,3-dipolar cycloaddition to form a
pyrrolo[3,4-b]isoxazole. The cycloaddition has not to date been accomplished, however an
unexpected retro-Claisen reaction is reported
Azido(benzoylacetonato-κ2 O,O′)[1-phenyl-3-(2-pyridylmethylimino)but-1-en-1-olato-κ3 N,N′,O]cobalt(III)
In the title complex, [Co(C16H15N2O)(C10H9O2)(N3)], the CoII atom adopts an octahedral coordination geometry by a tridentate Schiff base, a bidentate benzoylacetonate and an azide ligand. The imine N atom of the tridentate ligand is trans to the benzoyl O atom of the bidentate ligand and the azide ligand is trans to the acetyl O atom of the bidentate ligand. Non-classical intramolecular Caryl—H⋯O hydrogen bonds are present in the structure
New routes towards reutericyclin analogues
A range of N-acylpyrrolo[3,4-c]isoxazoles and derived N-5 acyltetramides has been prepared via a nitrile oxide dipolar cycloaddition approach, as analogues of the acyltetramic acid metabolite reutericyclin, of interest for their antibiotic potential against Gram-positive bacteria including hospital-acquired infections of resistant Clostridium difficile
Bidirectionally Deformable Motion Modulation For Video-based Human Pose Transfer
Video-based human pose transfer is a video-to-video generation task that
animates a plain source human image based on a series of target human poses.
Considering the difficulties in transferring highly structural patterns on the
garments and discontinuous poses, existing methods often generate
unsatisfactory results such as distorted textures and flickering artifacts. To
address these issues, we propose a novel Deformable Motion Modulation (DMM)
that utilizes geometric kernel offset with adaptive weight modulation to
simultaneously perform feature alignment and style transfer. Different from
normal style modulation used in style transfer, the proposed modulation
mechanism adaptively reconstructs smoothed frames from style codes according to
the object shape through an irregular receptive field of view. To enhance the
spatio-temporal consistency, we leverage bidirectional propagation to extract
the hidden motion information from a warped image sequence generated by noisy
poses. The proposed feature propagation significantly enhances the motion
prediction ability by forward and backward propagation. Both quantitative and
qualitative experimental results demonstrate superiority over the
state-of-the-arts in terms of image fidelity and visual continuity. The source
code is publicly available at github.com/rocketappslab/bdmm.Comment: ICCV 202
Bis{N′-[1-(2-pyridyl)ethylidene-κN]benzohydrazidato-κ2 N′,O}nickel(II)
In the title complex, [Ni(C14H12N3O)2], the NiII atom lies at the centre of a distorted octahedron formed by two tridentate hydrazone ligands. Intermolecular hydrogen bonds of the type C—H⋯X (X = N, O) link the complexes into a two-dimensional network
Tracking the evolution of a single composite particle during redox cycling for application in H-2 production
Composite materials consisting of metal and metal oxide phases are being researched intensively for various energy conversion applications where they are often expected to operate under redox conditions at elevated temperature. Understanding of the dynamics of composite evolution during redox cycling is still very limited, yet critical to maximising performance and increasing durability. Here we track the microstructural evolution of a single composite particle over 200 redox cycles for hydrogen production by chemical looping, using multi-length scale X-ray computed tomography. We show that redox cycling triggers a centrifugal redispersion of the metal phase and a centripetal clustering of porosity, both seemingly driven by the asymmetric nature of oxygen exchange in composites. Initially, the particle develops a large amount of internal porosity which boosts activity, but on the long term this facilitates structural and compositional reorganisation and eventually degradation. These results provide valuable insight into redox-driven microstructural changes and also for the design of new composite materials with enhanced durability
"The trauma of competition": the entry of Air Products Inc. into the industrial gases business in Britain and continental Europe 1947-1970
The British Oxygen Company (BOC) had a virtual monopoly on the supply of industrial gases (e.g. oxygen and acetylene) on the British market through the 1950s, when it was finally challenged by an American-based company, Air Products. Air Products Limited (APL) was able to undercut BOCs position, overcoming high barriers to entry to gain significant market share in this sector, which shares some features of network industries. Factors in this success included conditions imposed by the Board of Trade, APL’s innovations, BOC’s slow response, and favourable market conditions. APL’s success had implications for the internationalisation of the industrial gases industry
Extremely low nucleotide diversity in the X-linked region of papaya caused by a strong selective sweep
Collection sites of wild Costa Rican papaya. Table S2. Summary of sequencing statistics of re-sequenced papaya genomes. Table S3 Annotation of polymorphisms. Table S4. Synonymous site diversity for genes in the X-linked region. (DOCX 37 kb
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