Unbiased Image Synthesis via Manifold-Driven Sampling in Diffusion Models

Diffusion models are a potent class of generative models capable of producing high-quality images. However, they can face challenges related to data bias, favoring specific modes of data, especially when the training data does not accurately represent the true data distribution and exhibits skewed or imbalanced patterns. For instance, the CelebA dataset contains more female images than male images, leading to biased generation results and impacting downstream applications. To address this issue, we propose a novel method that leverages manifold guidance to mitigate data bias in diffusion models. Our key idea is to estimate the manifold of the training data using an unsupervised approach, and then use it to guide the sampling process of diffusion models. This encourages the generated images to be uniformly distributed on the data manifold without altering the model architecture or necessitating labels or retraining. Theoretical analysis and empirical evidence demonstrate the effectiveness of our method in improving the quality and unbiasedness of image generation compared to standard diffusion models

Isolated tracheal injury after whiplash

AbstractWhiplash, a sudden acceleration–deceleration movement that can cause diverse symptoms such as neck pain, cervicogenic headache, restricted neck movement, tingling of the arms (central cord syndrome), and dizziness. However, laryngotracheal injuries after whiplash are extremely rare. We report the case of a 25-year-old Taiwanese female who presented to the emergency department with severe posterior midline neck pain after a rear-end motorcycle collision. Her C-spine X-ray showed no definite fracture; furthermore, her neck noncontrast-enhanced CT scan revealed paratracheal free air. She was discharged uneventfully after a 12-h observation period. Laryngotracheal injuries after whiplash, a hyperextension–hyperflexion movement, are potentially life-threatening and could lead to airway obstruction. Such injuries should not be overlooked. To the best of our knowledge, this is the first case report of isolated laryngotracheal injury after whiplash

Anti-Hepatitis B Virus Effect and Possible Mechanism of Action of 3,4-O-Dicaffeoylquinic Acid In Vitro and In Vivo

The anti-hepatitis B activity of 3,4-O-dicaffeoylquinic acid isolated from Laggera alata was studied using the D-galactosamine- (D-GalN-) induced hepatocyte damage model, HepG2.2.15 cells, and with HBV transgenic mice. In vitro results showed that 3,4-O-dicaffeoylquinic acid improved HL-7702 hepatocyte viability and markedly inhibited the production of HBsAg and HBeAg. At a concentration of 100 μg/mL, its inhibitory rates on the expression levels of HBsAg and HBeAg were 89.96% and 81.01%, respectively. The content of hepatitis B virus covalently closed circular DNA (HBV cccDNA) in HepG2.2.15 cells was significantly decreased after the cells were treated with the test compound. In addition, 3,4-O-dicaffeoylquinic acid significantly increased the expression of heme oxygenase-1 (HO-1) in HepG2.2.15 cells. In vivo results indicated that the test compound at concentrations of 100 μg/mL significantly inhibited HBsAg production and increased HO-1 expression in HBV transgenic mice. In conclusion, this study verifies the anti-hepatitis B activity of 3,4-O-dicaffeoylquinic acid. The upregulation of HO-1 may contribute to the anti-HBV effect of this compound by reducing the stability of the HBV core protein, which blocks the refill of nuclear HBV cccDNA. Furthermore, the hepatoprotective effect of this compound may be mediated through its antioxidative/anti-inflammatory properties and by the induction of HO-1 expression

Improved Limits on an Exotic Spin- and Velocity-Dependent Interaction at the Micrometer Scale with an Ensemble-NV-Diamond Magnetometer

Searching for exotic interactions provides a path for exploring new particles beyond the standard model. Here, we used an ensemble-NV-diamond magnetometer to search for an exotic spin- and velocity-dependent interaction between polarized electron spins and unpolarized nucleons at the micrometer scale. A thin layer of nitrogen-vacancy electronic spin ensemble in diamond is utilized as both the solid-state spin quantum sensor and the polarized electron source, and a vibrating lead sphere serves as the moving unpolarized nucleon source. The exotic interaction is searched by detecting the possible effective magnetic field induced by the moving unpolarized nucleon source using the ensemble-NV-diamond magnetometer. Our result establishes new bounds for the coupling parameter $f_\perp$ within the force range from 5 to 400 $\rm \mu$m. The upper limit of the coupling parameter at 100 $\rm \mu$m is $\lvert f_\perp \rvert \leq 1.1\times 10^{-11}$, which is 3 orders of magnitude more stringent than the previous constraint. This result shows that NV ensemble can be a promising platform to search for hypothetical particles beyond the standard model

Natural Phenolic Acids and Their Derivatives against Human Viral Infections

Natural compounds with structural diversity and complexity offer a great chance to find new antiviral agents. Phenolic acids have attracted considerable attention due to their potent antiviral abilities and unique mechanisms. The aim of this review is to report new discoveries and update pertaining to antiviral phenolic acids. The antiviral phenolic acids were classified according to their structural properties and antiviral types. Meanwhile, the antiviral characteristics and structure-activity relationships of phenolic acids and their derivatives were summarized. Natural phenolic acids and their derivatives possess potent inhibitory effects on multiple viruses in humans such as human immunodeficiency virus, hepatitis C virus, hepatitis B virus, herpes simplex virus, influenza virus and respiratory syncytial virus etc. In particular, caffeic acid/gallic acid and their derivatives exhibit outstanding antiviral properties through a variety of modes of action. In conclusion, naturally derived phenolic acids especially caffeic acid/gallic acid and their derivatives may be regarded as novel promising antiviral leads or candidates. Additionally, scarcely any of these compounds have been used as antiviral treatments in clinical practice. Therefore, these phenolic acids with diverse skeletons and mechanisms provide us an excellent resource for finding novel antiviral drugs