162 research outputs found
Forward simulation of backward SDEs
We introduce a forward scheme to simulate backward SDEs and analyze the error of the scheme. Finally, we demonstrate the strength of the new algorithm by solving some financial problems numerically
A tudományos kommunikáció története a Journal des Scavans-tól az open access-ig
Background:
The foamy viral genome encodes four central purine-rich elements localized in the integrase-coding region of pol. Previously, we have shown that the first two of these RNA elements (A and B) are required for protease dimerization and activation. The D element functions as internal polypurine tract during reverse transcription. Peters et al., described the third element (C) as essential for gag expression suggesting that it might serve as an RNA export element for the unspliced genomic transcript.
Results:
Here, we analysed env splicing and demonstrate that the described C element composed of three GAA repeats known to bind SR proteins regulates env splicing, thus balancing the amount of gag/pol mRNAs. Deletion of the C element effectively promotes a splice site switch from a newly identified env splice acceptor to the intrinsically strong downstream localised env 3′ splice acceptor permitting complete splicing of almost all LTR derived transcripts. We provide evidence that repression of this env splice acceptor is a prerequisite for gag expression. This repression is achieved by the C element, resulting in impaired branch point recognition and SF1/mBBP binding. Separating the branch point from the overlapping purine-rich C element, by insertion of only 20 nucleotides, liberated repression and fully restored splicing to the intrinsically strong env 3′ splice site. This indicated that the cis-acting element might repress splicing by blocking the recognition of essential splice site signals.
Conclusions:
The foamy viral purine-rich C element regulates splicing by suppressing the branch point recognition of the strongest env splice acceptor. It is essential for the formation of unspliced gag and singly spliced pol transcripts
Augmenting Large Language Models with Audio Generation Capabilities
Chatbots or conversational agent interfaces utilize large language models (LLMs) to provide text responses to user queries. However, such chatbots are not capable of receiving audio input and providing generated audio as a response. This disclosure describes techniques to augment a LLM with an interface to an audio generation model. The LLM is fine-tuned to train it to leverage an API to access the audio generation model when input queries request query response in audio form. The trained LLM performs reasoning tasks and generates prompts for the audio generation model. The user-provided audio input and the LLM-generated prompts are fed to the audio generation model which generates audio. The output audio is analyzed to determine attributes as textual description. The LLM can perform multiple rounds of reasoning, prompt generation, and calling the audio generation model based on previously generated audio and associated textual descriptions. The ultimate audio output as generated by the audio generation model is provided as a response to the user query
Brain2Music: Reconstructing Music from Human Brain Activity
The process of reconstructing experiences from human brain activity offers a
unique lens into how the brain interprets and represents the world. In this
paper, we introduce a method for reconstructing music from brain activity,
captured using functional magnetic resonance imaging (fMRI). Our approach uses
either music retrieval or the MusicLM music generation model conditioned on
embeddings derived from fMRI data. The generated music resembles the musical
stimuli that human subjects experienced, with respect to semantic properties
like genre, instrumentation, and mood. We investigate the relationship between
different components of MusicLM and brain activity through a voxel-wise
encoding modeling analysis. Furthermore, we discuss which brain regions
represent information derived from purely textual descriptions of music
stimuli. We provide supplementary material including examples of the
reconstructed music at https://google-research.github.io/seanet/brain2musicComment: Preprint; 21 pages; supplementary material:
https://google-research.github.io/seanet/brain2musi
Inverted bulk-heterojunction solar cell with cross-linked hole-blocking layer
AbstractWe have developed a hole-blocking layer for bulk-heterojunction solar cells based on cross-linked polyethylenimine (PEI). We tested five different ether-based cross-linkers and found that all of them give comparable solar cell efficiencies. The initial idea that a cross-linked layer is more solvent resistant compared to a pristine PEI layer could not be confirmed. With and without cross-linking, the PEI layer sticks very well to the surface of the indium–tin–oxide electrode and cannot be removed by solvents used to process PEI or common organic semiconductors. The cross-linked PEI hole-blocking layer functions for multiple donor–acceptor blends. We found that using cross-linkers improves the reproducibility of the device fabrication process
The molecular fingerprint of lung inflammation after blunt chest trauma
Abstract
Background
After severe blunt chest trauma, the development of an acute lung injury (ALI) is often associated with severe or even lethal complications. Especially in multiple injured patients after blunt chest trauma ALI/ARDS [acute respiratory distress syndrome (ARDS)] is frequent. However, in the initial posttraumatic phase, inflammatory clinical signs are often not apparent and underlying changes in gene-expression profile are unknown.
Methods
Therefore, inflammation in lung tissue following blunt chest trauma was characterized in a well-defined bilateral lung injury model. Using DNA microarrays representing 9240 genes, the temporal sequence of blunt chest trauma-induced gene-expression patterns in lung tissue was examined.
Results
The results suggest an activation of a highly complex transcriptional program in response to chest trauma. Chest trauma led to elevated expression levels of inflammatory and coagulatory proteins (such as TNFα receptor, IL-1α, IL-1β, C3, NF-κB and plasminogen activator). However, upregulation of proteins was found, usually incoherent of exerting effects in blunt thoracic trauma (pendrin, resistin, metallothionein and glucocorticoid-induced leucine zipper). Furthermore, significant downregulation was observed as early as 10 min after trauma for cytokines and complement factors (LCR-1, C4) as well as for intracellular signaling molecules (inhibitory protein phosphatase) and ion-channels (voltage-dependent Ca2+ channel).
Conclusions
Taken together, the provided global perspective of the inflammatory response following blunt chest trauma could provide a molecular framework for future research in trauma pathophysiology.http://deepblue.lib.umich.edu/bitstream/2027.42/113091/1/40001_2015_Article_164.pd
Cynomolgus monkey's choroid reference database derived from hybrid deep learning optical coherence tomography segmentation.
Cynomolgus monkeys exhibit human-like features, such as a fovea, so they are often used in non-clinical research. Nevertheless, little is known about the natural variation of the choroidal thickness in relation to origin and sex. A combination of deep learning and a deterministic computer vision algorithm was applied for automatic segmentation of foveolar optical coherence tomography images in cynomolgus monkeys. The main evaluation parameters were choroidal thickness and surface area directed from the deepest point on OCT images within the fovea, marked as the nulla with regard to sex and origin. Reference choroid landmarks were set underneath the nulla and at 500 µm intervals laterally up to a distance of 2000 µm nasally and temporally, complemented by a sub-analysis of the central bouquet of cones. 203 animals contributed 374 eyes for a reference choroid database. The overall average central choroidal thickness was 193 µm with a coefficient of variation of 7.8%, and the overall mean surface area of the central bouquet temporally was 19,335 µm2 and nasally was 19,283 µm2. The choroidal thickness of the fovea appears relatively homogeneous between the sexes and the studied origins. However, considerable natural variation has been observed, which needs to be appreciated
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