324 research outputs found
CoPL: Contextual Prompt Learning for Vision-Language Understanding
Recent advances in multimodal learning has resulted in powerful
vision-language models, whose representations are generalizable across a
variety of downstream tasks. Recently, their generalization ability has been
further extended by incorporating trainable prompts, borrowed from the natural
language processing literature. While such prompt learning techniques have
shown impressive results, we identify that these prompts are trained based on
global image features which limits itself in two aspects: First, by using
global features, these prompts could be focusing less on the discriminative
foreground image, resulting in poor generalization to various
out-of-distribution test cases. Second, existing work weights all prompts
equally whereas intuitively, prompts should be reweighed according to the
semantics of the image. We address these as part of our proposed Contextual
Prompt Learning (CoPL) framework, capable of aligning the prompts to the
localized features of the image. Our key innovations over earlier works include
using local image features as part of the prompt learning process, and more
crucially, learning to weight these prompts based on local features that are
appropriate for the task at hand. This gives us dynamic prompts that are both
aligned to local image features as well as aware of local contextual
relationships. Our extensive set of experiments on a variety of standard and
few-shot datasets show that our method produces substantially improved
performance when compared to the current state of the art methods. We also
demonstrate both few-shot and out-of-distribution performance to establish the
utility of learning dynamic prompts that are aligned to local image features.Comment: Accepted at AAAI 202
Effect of thyroid hormone concentration on the transcriptional response underlying induced metamorphosis in the Mexican axolotl (Ambystoma)
<p>Abstract</p> <p>Background</p> <p>Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T<sub>4</sub>). We induced metamorphosis in juvenile Mexican axolotls (<it>Ambystoma mexicanum</it>) using 5 and 50 nM T<sub>4</sub>, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances.</p> <p>Results</p> <p>Individuals reared in the higher T<sub>4 </sub>concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis was delayed in the lower T<sub>4 </sub>concentration and none of the individuals completed metamorphosis by Day 28. We identified 402 genes that were statistically differentially expressed by ≥ two-fold between T<sub>4 </sub>treatments at one or more non-Day 0 sampling times. To complement this analysis, we used linear and quadratic regression to identify 542 and 709 genes that were differentially expressed by ≥ two-fold in the 5 and 50 nM T<sub>4 </sub>treatments, respectively.</p> <p>Conclusion</p> <p>We found that T<sub>4 </sub>concentration affected the timing of gene expression and the shape of temporal gene expression profiles. However, essentially all of the identified genes were similarly affected by 5 and 50 nM T<sub>4</sub>. We discuss genes and biological processes that appear to be common to salamander and anuran metamorphosis, and also highlight clear transcriptional differences. Our results show that gene expression in axolotls is diverse and precise, and that axolotls provide new insights about amphibian metamorphosis.</p
Evaluation of different custom angulated elastic glass fibre post on fracture resistance of maxillary central incisor: an in vitro study.
Background: Restoring Endodontically treated teeth (ETT) can be challenging for most dentists, particularly when a significant tooth structure is lost. Depending on the coronal tooth structure remaining and the technique used (direct or indirect), endodontic anchorage can involve either a cast post and core or a prefabricated post.
Aim: This study aimed to investigate the effect of different custom angulated, i.e.,0°,5°,10°,15° elastic glass fibre post (Everstick post) on fracture resistance of maxillary central incisors.
Materials and methods: A total of forty-eight single-rooted maxillary central incisors were selected. All the samples were decoronated 2mm above the CEJ and endodontically treated. Post-space preparation was done for all the samples using peesoreamers ranging in size from 1-3. The samples were then randomly divided into four groups (n=12) based on the different angulations, i.e., the angle between the core and the long axis of the root, with 0°, 5°, 10°, and 15° angulations, respectively. The fit of each post in the root canal was verified. Before cementation, the coronal part of each post was bent according to their respective groups. Dual-cure resin cement was used for luting the posts and cured subsequently. The fracture resistance of all the samples was evaluated using the universal testing machine after they were mounted in self-cure acrylic resin blocks. The data were analysed using One- way ANOVA and Tukey’s post-hoc test.
Results: Group I exhibited the highest mean fracture resistance compared to other groups. However, One-way ANOVA showed no significant differences (p=0.161) between the four groups.
Conclusion: Everstick fibre posts are a preferable alternative for maxillary central incisors with core angulations up to 15° between coronal and radicular segments as they provide better fracture resistance with a more favourable stress distribution
Effect of thyroid hormone concentration on the transcriptional response underlying induced metamorphosis in the Mexican axolotl (\u3ci\u3eAmbystoma\u3c/i\u3e)
Background
Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4). We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum) using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances.
Results
Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis was delayed in the lower T4 concentration and none of the individuals completed metamorphosis by Day 28. We identified 402 genes that were statistically differentially expressed by ≥ two-fold between T4 treatments at one or more non-Day 0 sampling times. To complement this analysis, we used linear and quadratic regression to identify 542 and 709 genes that were differentially expressed by ≥ two-fold in the 5 and 50 nM T4 treatments, respectively.
Conclusion
We found that T4 concentration affected the timing of gene expression and the shape of temporal gene expression profiles. However, essentially all of the identified genes were similarly affected by 5 and 50 nM T4. We discuss genes and biological processes that appear to be common to salamander and anuran metamorphosis, and also highlight clear transcriptional differences. Our results show that gene expression in axolotls is diverse and precise, and that axolotls provide new insights about amphibian metamorphosis
Iterative Multi-granular Image Editing using Diffusion Models
Recent advances in text-guided image synthesis has dramatically changed how
creative professionals generate artistic and aesthetically pleasing visual
assets. To fully support such creative endeavors, the process should possess
the ability to: 1) iteratively edit the generations and 2) control the spatial
reach of desired changes (global, local or anything in between). We formalize
this pragmatic problem setting as Iterative Multi-granular Editing. While there
has been substantial progress with diffusion-based models for image synthesis
and editing, they are all one shot (i.e., no iterative editing capabilities)
and do not naturally yield multi-granular control (i.e., covering the full
spectrum of local-to-global edits). To overcome these drawbacks, we propose
EMILIE: Iterative Multi-granular Image Editor. EMILIE introduces a novel latent
iteration strategy, which re-purposes a pre-trained diffusion model to
facilitate iterative editing. This is complemented by a gradient control
operation for multi-granular control. We introduce a new benchmark dataset to
evaluate our newly proposed setting. We conduct exhaustive quantitatively and
qualitatively evaluation against recent state-of-the-art approaches adapted to
our task, to being out the mettle of EMILIE. We hope our work would attract
attention to this newly identified, pragmatic problem setting.Comment: Pre-prin
2,4,6,8-Tetrakis(4-ethylphenyl)-3,7-diazabicyclo[3.3.1]nonan-9-one
The bicyclo[3.3.1]nonane ring in the title compound, C39H44N2O, adopts a chair–boat conformation with the four benzene rings being directed away from the carbonyl group. The presence of C—H⋯O contacts leads to helical supramolecular chains along the b axis
Sal-Site: Integrating new and existing ambystomatid salamander research and informational resources
Salamanders of the genus Ambystoma are a unique model organism system because they enable natural history and biomedical research in the laboratory or field. We developed Sal-Site to integrate new and existing ambystomatid salamander research resources in support of this model system. Sal-Site hosts six important resources: 1) Salamander Genome Project: an information-based web-site describing progress in genome resource development, 2) Ambystoma EST Database: a database of manually edited and analyzed contigs assembled from ESTs that were collected from A. tigrinum tigrinum and A. mexicanum, 3) Ambystoma Gene Collection: a database containing full-length protein-coding sequences, 4) Ambystoma Map and Marker Collection: an image and database resource that shows the location of mapped markers on linkage groups, provides information about markers, and provides integrating links to Ambystoma EST Database and Ambystoma Gene Collection databases, 5) Ambystoma Genetic Stock Center: a website and collection of databases that describe an NSF funded salamander rearing facility that generates and distributes biological materials to researchers and educators throughout the world, and 6) Ambystoma Research Coordination Network: a web-site detailing current research projects and activities involving an international group of researchers. Sal-Site is accessible at
Feasible pathways for the multi-dimensional synthesis of carboxylic acid from benzo-pyrone methyl ketone
3-Acetyl coumarin derivatives are the key synthons to the numerous numbers of heterocyclic compound syntheses. Due to the wide spectrum applications of benzopyran derivatives in pharma, research, food technology and material science there is a multitude number of methodologies feasible to synthesize benzo pyrone heterocyclic derivatives. This article articulates the synthesis and molecular structure confirmation of oxidative product starting from methyl ketone compound by haloform reaction. Design of benign path ways for instance room temperature, reflux conditions and water bath mediated synthesis of desired compounds in expected yields is the foremost intent of the article. Solvent and catalyst optimization studies were carried to elevate the product yield and to precede the reaction in sustainable way. Furthermore compounds are confirmed by spectroscopic analytical methods such as 1HNMR, 13CNMR, IR and HRMS spectroscopy. This article paves the way to researchers to explore these analogues to explore disparate medicinal applications
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