Competition between structural distortion and magnetic moment formation in fullerene C20_{20}

We investigated the effect of on-site Coulomb interactions on the structural and magnetic ground state of the fullerene C$_{20}$ based on density-functional-theory calculations within the local density approximation plus on-site Coulomb corrections (LDA+$U$). The total energies of the high symmetry ($I_{h}$) and distorted ($D_{3d}$) structures of C$_{20}$ were calculated for different spin configurations. The ground state configurations were found to depend on the forms of exchange-correlation potentials and the on-site Coulomb interaction parameter $U$, reflecting the subtle nature of the competition between Jahn-Teller distortion and magnetic instability in fullerene C$_{20}$. While the non-magnetic state of the distorted $D_{3d}$ structure is robust for small $U$, a magnetic ground state of the undistorted $I_{h}$ structure emerges for $U$ larger than 4 eV when the LDA exchange-correlation potential is employed.Comment: 4 figures, 1 tabl

Multiphoton tissue imaging by using moxifloxacin

Multiphoton microscopy has been widely used for in-vivo tissue imaging of various biological studies. However, its application to clinical studies has been limited due to either lack of clinically compatible exogenous contrast agents or weak autofluorescence of tissues. We investigated moxifloxacin as a contrast agent of cells for multiphoton tissue imaging. Moxifloxacin is an FDA approved antibiotic with relatively good pharmacokinetic properties for tissue penetration and intrinsic fluorescence. Two-photon microscopy (TPM) of moxifloxacin treated mouse corneas showed good tissue penetration and high concentration inside the corneal cells [1]. Cell labeling of moxifloxacin was tested in both cultured cells and isolated immune cells. Moxifloxacin tissue applications were tested in various mouse organs such as the skin, small intestine, and brain. Most of tissues were labeled well via topical administration, and only the skin required additional gentle removal of the outermost stratum corneum by tape stripping. TPM of these tissues showed non-specific cell labeling of moxifloxacin and fluorescence enhancement [2]. Although most of experimental results were from mouse tissues, its clinical application would be possible. Clinical application is promising since imaging based on moxifloxacin labeling could be 10 times faster than imaging based on endogenous fluorescence. Moxifloxacin labeling of cultured cells was demonstrated by comparing TPM images with and without moxifloxacin treatment. Bright fluorescence inside cells were observed only with moxifloxacin at the same imaging condition. TPM of the skin dermis visualized many dermal cells with increased fluorescence, and TPM of the villus in the small intestine showed the covering epithelial cells and cells inside the villus clearly. Please click Additional Files below to see the full abstract

Epitaxially strained ultrathin LaNiO3_3/LaAlO3_3 and LaNiO3_3/SrTiO3_3 superlattices: a density functional theory + UU study

By employing first-principles electronic structure calculations we investigate nickelate superlattices [LaNiO$_3$]$_1$/[LaAlO$_3$]$_1$ and [LaNiO$_3$]$_1$/[SrTiO$_3$]$_1$ with (001) orientation under epitaxial tensile strain. Within density functional theory augmented by mean-field treatement of on-site electronic correlations, the ground states show remarkable dependence on the correlation strength and the strain. In the weakly and intermediately correlated regimes with small epitaxial strain, the charge-disproportionated insulating states with antiferromagneitc order is favored over the other orbital and spin ordered phases. On the other hand, in the strongly correlated regime or under the large tensile strain, ferromagnetic spin states with Jahn-Teller orbital order become most stable. The effect from polar interfaces in LaNiO$_3$]$_1$/[SrTiO$_3$]$_1$ is found to be noticeable in our single-layered geometry. Detailed discussion is presented in comparison with previous experimental and theoretical studies.Comment: 9 pages, 8 figure

Introducing Competition to Boost the Transferability of Targeted Adversarial Examples through Clean Feature Mixup

Deep neural networks are widely known to be susceptible to adversarial examples, which can cause incorrect predictions through subtle input modifications. These adversarial examples tend to be transferable between models, but targeted attacks still have lower attack success rates due to significant variations in decision boundaries. To enhance the transferability of targeted adversarial examples, we propose introducing competition into the optimization process. Our idea is to craft adversarial perturbations in the presence of two new types of competitor noises: adversarial perturbations towards different target classes and friendly perturbations towards the correct class. With these competitors, even if an adversarial example deceives a network to extract specific features leading to the target class, this disturbance can be suppressed by other competitors. Therefore, within this competition, adversarial examples should take different attack strategies by leveraging more diverse features to overwhelm their interference, leading to improving their transferability to different models. Considering the computational complexity, we efficiently simulate various interference from these two types of competitors in feature space by randomly mixing up stored clean features in the model inference and named this method Clean Feature Mixup (CFM). Our extensive experimental results on the ImageNet-Compatible and CIFAR-10 datasets show that the proposed method outperforms the existing baselines with a clear margin. Our code is available at https://github.com/dreamflake/CFM.Comment: CVPR 2023 camera-read

Acute Interstitial Pneumonia in Siblings: A Case Report

Acute interstitial pneumonia (AIP) is a rapidly progressive condition of unknown cause that occurs in a previously healthy individual and produces the histologic findings of diffuse alveolar damage. Since the term AIP was first introduced in 1986, there have been very few case reports of AIP in children. Here we present a case of AIP in a 3-yr-old girl whose other two siblings showed similar radiologic findings. The patient was confirmed to have AIP from autopsy showing histological findings of diffuse alveolar damage and proliferation of fibroblasts. Her 3-yr-old brother was also clinically and radiologically highly suspected as having AIP, and the other asymptomatic 8-yr-old sister was radiologically suspected as having AIP