14 research outputs found
DreamAvatar: Text-and-Shape Guided 3D Human Avatar Generation via Diffusion Models
We present DreamAvatar, a text-and-shape guided framework for generating
high-quality 3D human avatars with controllable poses. While encouraging
results have been reported by recent methods on text-guided 3D common object
generation, generating high-quality human avatars remains an open challenge due
to the complexity of the human body's shape, pose, and appearance. We propose
DreamAvatar to tackle this challenge, which utilizes a trainable NeRF for
predicting density and color for 3D points and pretrained text-to-image
diffusion models for providing 2D self-supervision. Specifically, we leverage
the SMPL model to provide shape and pose guidance for the generation. We
introduce a dual-observation-space design that involves the joint optimization
of a canonical space and a posed space that are related by a learnable
deformation field. This facilitates the generation of more complete textures
and geometry faithful to the target pose. We also jointly optimize the losses
computed from the full body and from the zoomed-in 3D head to alleviate the
common multi-face ''Janus'' problem and improve facial details in the generated
avatars. Extensive evaluations demonstrate that DreamAvatar significantly
outperforms existing methods, establishing a new state-of-the-art for
text-and-shape guided 3D human avatar generation.Comment: Project page: https://yukangcao.github.io/DreamAvatar
MA-NeRF: Motion-Assisted Neural Radiance Fields for Face Synthesis from Sparse Images
We address the problem of photorealistic 3D face avatar synthesis from sparse
images. Existing Parametric models for face avatar reconstruction struggle to
generate details that originate from inputs. Meanwhile, although current
NeRF-based avatar methods provide promising results for novel view synthesis,
they fail to generalize well for unseen expressions. We improve from NeRF and
propose a novel framework that, by leveraging the parametric 3DMM models, can
reconstruct a high-fidelity drivable face avatar and successfully handle the
unseen expressions. At the core of our implementation are structured
displacement feature and semantic-aware learning module. Our structured
displacement feature will introduce the motion prior as an additional
constraints and help perform better for unseen expressions, by constructing
displacement volume. Besides, the semantic-aware learning incorporates
multi-level prior, e.g., semantic embedding, learnable latent code, to lift the
performance to a higher level. Thorough experiments have been doen both
quantitatively and qualitatively to demonstrate the design of our framework,
and our method achieves much better results than the current state-of-the-arts
HeadSculpt: Crafting 3D Head Avatars with Text
Recently, text-guided 3D generative methods have made remarkable advancements
in producing high-quality textures and geometry, capitalizing on the
proliferation of large vision-language and image diffusion models. However,
existing methods still struggle to create high-fidelity 3D head avatars in two
aspects: (1) They rely mostly on a pre-trained text-to-image diffusion model
whilst missing the necessary 3D awareness and head priors. This makes them
prone to inconsistency and geometric distortions in the generated avatars. (2)
They fall short in fine-grained editing. This is primarily due to the inherited
limitations from the pre-trained 2D image diffusion models, which become more
pronounced when it comes to 3D head avatars. In this work, we address these
challenges by introducing a versatile coarse-to-fine pipeline dubbed HeadSculpt
for crafting (i.e., generating and editing) 3D head avatars from textual
prompts. Specifically, we first equip the diffusion model with 3D awareness by
leveraging landmark-based control and a learned textual embedding representing
the back view appearance of heads, enabling 3D-consistent head avatar
generations. We further propose a novel identity-aware editing score
distillation strategy to optimize a textured mesh with a high-resolution
differentiable rendering technique. This enables identity preservation while
following the editing instruction. We showcase HeadSculpt's superior fidelity
and editing capabilities through comprehensive experiments and comparisons with
existing methods.Comment: Webpage: https://brandonhan.uk/HeadSculpt
Patchouli alcohol improved diarrhea-predominant irritable bowel syndrome by regulating excitatory neurotransmission in the myenteric plexus of rats
Background and Purpose: Irritable bowel syndrome (IBS) is usually associated with chronic gastrointestinal disorders. Its most common subtype is accompanied with diarrhea (IBS-D). The enteric nervous system (ENS) modulates major gastrointestinal motility and functions whose aberration may induce IBS-D. The enteric neurons are susceptible to long-term neurotransmitter level alterations. The patchouli alcohol (PA), extracted from Pogostemonis Herba, has been reported to regulate neurotransmitter release in the ENS, while its effectiveness against IBS-D and the underlying mechanism remain unknown.Experimental Approach: In this study, we established an IBS-D model in rats through chronic restraint stress. We administered the rats with 5, 10, and 20 mg/kg of PA for intestinal and visceral examinations. The longitudinal muscle myenteric plexus (LMMP) neurons were further immunohistochemically stained for quantitative, morphological, and neurotransmitters analyses.Key Results: We found that PA decreased visceral sensitivity, diarrhea symptoms and intestinal transit in the IBS-D rats. Meanwhile, 10 and 20 mg/kg of PA significantly reduced the proportion of excitatory LMMP neurons in the distal colon, decreased the number of acetylcholine (Ach)- and substance P (SP)-positive neurons in the distal colon and restored the levels of Ach and SP in the IBS-D rats.Conclusion and Implications: These findings indicated that PA modulated LMMP excitatory neuron activities, improved intestinal motility and alleviated IBS-induced diarrheal symptoms, suggesting the potential therapeutic efficacy of PA against IBS-D
OmniForce: On Human-Centered, Large Model Empowered and Cloud-Edge Collaborative AutoML System
Automated machine learning (AutoML) seeks to build ML models with minimal
human effort. While considerable research has been conducted in the area of
AutoML in general, aiming to take humans out of the loop when building
artificial intelligence (AI) applications, scant literature has focused on how
AutoML works well in open-environment scenarios such as the process of training
and updating large models, industrial supply chains or the industrial
metaverse, where people often face open-loop problems during the search
process: they must continuously collect data, update data and models, satisfy
the requirements of the development and deployment environment, support massive
devices, modify evaluation metrics, etc. Addressing the open-environment issue
with pure data-driven approaches requires considerable data, computing
resources, and effort from dedicated data engineers, making current AutoML
systems and platforms inefficient and computationally intractable.
Human-computer interaction is a practical and feasible way to tackle the
problem of open-environment AI. In this paper, we introduce OmniForce, a
human-centered AutoML (HAML) system that yields both human-assisted ML and
ML-assisted human techniques, to put an AutoML system into practice and build
adaptive AI in open-environment scenarios. Specifically, we present OmniForce
in terms of ML version management; pipeline-driven development and deployment
collaborations; a flexible search strategy framework; and widely provisioned
and crowdsourced application algorithms, including large models. Furthermore,
the (large) models constructed by OmniForce can be automatically turned into
remote services in a few minutes; this process is dubbed model as a service
(MaaS). Experimental results obtained in multiple search spaces and real-world
use cases demonstrate the efficacy and efficiency of OmniForce
Does Early Victimization of School Bullies Affect Core Self-Evaluations in Young Adulthood? A Moderated Mediation Model
Early victimization is associated with a range of psychological adaptation problems in young adulthood, including core self-evaluations. However, little is known about the mechanisms underlying the association between early victimization and young adults’ core self-evaluations. This study examined the mediating role of negative cognitive processing bias and the moderating role of resilience in the relationship. A total of 972 college students were recruited to complete measures of early victimization, negative cognitive processing bias, resilience, and core self-evaluations. The results showed that early victimization significantly and negatively predicted the core self-evaluations in young adulthood. The negative association between early victimization and core self-evaluations was completely mediated by negative cognitive processing bias. Resilience moderated the relationship between early victimization and negative cognitive bias, and the relationship between negative cognitive processing bias and core self-evaluations. Resilience has both risk-buffering and risk-enhancing effects. In light of these results, in order to help victims maintain good mental health, we should intervene in individual cognitive factors. Notably, while resilience is a protective factor in most cases, the benefits of resilience should not be overstated. So, we should not only cultivate students’ resilience but also provide them with more support and resources and intervene in risk factors at the same time
Cytotoxic Compounds from Marine Fungi: Sources, Structures, and Bioactivity
Marine fungi, such as species from the Penicillium and Aspergillus genera, are prolific producers of a diversity of natural products with cytotoxic properties. These fungi have been successfully isolated and identified from various marine sources, including sponges, coral, algae, mangroves, sediment, and seawater. The cytotoxic compounds derived from marine fungi can be categorized into five distinct classes: polyketides, peptides, terpenoids and sterols, hybrids, and other miscellaneous compounds. Notably, the pre-eminent group among these compounds comprises polyketides, accounting for 307 out of 642 identified compounds. Particularly, within this collection, 23 out of the 642 compounds exhibit remarkable cytotoxic potency, with IC50 values measured at the nanomolar (nM) or nanogram per milliliter (ng/mL) levels. This review elucidates the originating fungal strains, the sources of isolation, chemical structures, and the noteworthy antitumor activity of the 642 novel natural products isolated from marine fungi. The scope of this review encompasses the period from 1991 to 2023
DataSheet1_Patchouli alcohol improved diarrhea-predominant irritable bowel syndrome by regulating excitatory neurotransmission in the myenteric plexus of rats.PDF
Background and Purpose: Irritable bowel syndrome (IBS) is usually associated with chronic gastrointestinal disorders. Its most common subtype is accompanied with diarrhea (IBS-D). The enteric nervous system (ENS) modulates major gastrointestinal motility and functions whose aberration may induce IBS-D. The enteric neurons are susceptible to long-term neurotransmitter level alterations. The patchouli alcohol (PA), extracted from Pogostemonis Herba, has been reported to regulate neurotransmitter release in the ENS, while its effectiveness against IBS-D and the underlying mechanism remain unknown.Experimental Approach: In this study, we established an IBS-D model in rats through chronic restraint stress. We administered the rats with 5, 10, and 20 mg/kg of PA for intestinal and visceral examinations. The longitudinal muscle myenteric plexus (LMMP) neurons were further immunohistochemically stained for quantitative, morphological, and neurotransmitters analyses.Key Results: We found that PA decreased visceral sensitivity, diarrhea symptoms and intestinal transit in the IBS-D rats. Meanwhile, 10 and 20 mg/kg of PA significantly reduced the proportion of excitatory LMMP neurons in the distal colon, decreased the number of acetylcholine (Ach)- and substance P (SP)-positive neurons in the distal colon and restored the levels of Ach and SP in the IBS-D rats.Conclusion and Implications: These findings indicated that PA modulated LMMP excitatory neuron activities, improved intestinal motility and alleviated IBS-induced diarrheal symptoms, suggesting the potential therapeutic efficacy of PA against IBS-D.</p