255 research outputs found
Detection of gfp expression from gfp-labelled bacteria spot inoculated onto sugarcane tissues
Green fluorescent protein (GFP) as a marker gene has facilitated biological research in plant-microbe interactions. However, there is one major limiting factor in the detection of GFP in living organisms whose cells emit background autofluorescence. In this study, Herbaspirillum sp. B501gfp1 bacterial cells were spot inoculated onto 5 month-old sterile micro-propagated sugarcane tissues to detect if the GFP fluorescence expression could be distinguished from the tissue’s background fluorescence. Stem tissues and leaf sections mounted on glass slides were directly inoculated with a single touch using the tip of a syringe previously dipped into the inoculum containing 108 bacterial cells/ml. We observed that GFP fluorescence could be easily distinguished in the stem than in the leaf tissues. However, the brightness level of the fluorescence varied with time as a result of fluctuations in the bacterial celldensity. The presence of chloroplasts in the leaf tissues of sugarcane requires the use of bright GFP variants when monitoring bacteria-plant interactions using GFP labelled bacteria
Visio-Linguistic Brain Encoding
Enabling effective brain-computer interfaces requires understanding how the
human brain encodes stimuli across modalities such as visual, language (or
text), etc. Brain encoding aims at constructing fMRI brain activity given a
stimulus. There exists a plethora of neural encoding models which study brain
encoding for single mode stimuli: visual (pretrained CNNs) or text (pretrained
language models). Few recent papers have also obtained separate visual and text
representation models and performed late-fusion using simple heuristics.
However, previous work has failed to explore: (a) the effectiveness of image
Transformer models for encoding visual stimuli, and (b) co-attentive
multi-modal modeling for visual and text reasoning. In this paper, we
systematically explore the efficacy of image Transformers (ViT, DEiT, and BEiT)
and multi-modal Transformers (VisualBERT, LXMERT, and CLIP) for brain encoding.
Extensive experiments on two popular datasets, BOLD5000 and Pereira, provide
the following insights. (1) To the best of our knowledge, we are the first to
investigate the effectiveness of image and multi-modal Transformers for brain
encoding. (2) We find that VisualBERT, a multi-modal Transformer, significantly
outperforms previously proposed single-mode CNNs, image Transformers as well as
other previously proposed multi-modal models, thereby establishing new
state-of-the-art. The supremacy of visio-linguistic models raises the question
of whether the responses elicited in the visual regions are affected implicitly
by linguistic processing even when passively viewing images. Future fMRI tasks
can verify this computational insight in an appropriate experimental setting.Comment: 18 pages, 13 figure
Closed conformal Killing-Yano tensor and geodesic integrability
Assuming the existence of a single rank-2 closed conformal Killing-Yano
tensor with a certain symmetry we show that there exist mutually commuting
rank-2 Killing tensors and Killing vectors. We also discuss the condition of
separation of variables for the geodesic Hamilton-Jacobi equations.Comment: 17 pages, no figure, LaTe
On the Classification of Brane Tilings
We present a computationally efficient algorithm that can be used to generate
all possible brane tilings. Brane tilings represent the largest class of
superconformal theories with known AdS duals in 3+1 and also 2+1 dimensions and
have proved useful for describing the physics of both D3 branes and also M2
branes probing Calabi-Yau singularities. This algorithm has been implemented
and is used to generate all possible brane tilings with at most 6
superpotential terms, including consistent and inconsistent brane tilings. The
collection of inconsistent tilings found in this work form the most
comprehensive study of such objects to date.Comment: 33 pages, 12 figures, 15 table
- …