Domain Adaptation via Bidirectional Cross-Attention Transformer

Domain Adaptation (DA) aims to leverage the knowledge learned from a source domain with ample labeled data to a target domain with unlabeled data only. Most existing studies on DA contribute to learning domain-invariant feature representations for both domains by minimizing the domain gap based on convolution-based neural networks. Recently, vision transformers significantly improved performance in multiple vision tasks. Built on vision transformers, in this paper we propose a Bidirectional Cross-Attention Transformer (BCAT) for DA with the aim to improve the performance. In the proposed BCAT, the attention mechanism can extract implicit source and target mixup feature representations to narrow the domain discrepancy. Specifically, in BCAT, we design a weight-sharing quadruple-branch transformer with a bidirectional cross-attention mechanism to learn domain-invariant feature representations. Extensive experiments demonstrate that the proposed BCAT model achieves superior performance on four benchmark datasets over existing state-of-the-art DA methods that are based on convolutions or transformers

STAR-RIS-Assisted Privacy Protection in Semantic Communication System

Semantic communication (SemCom) has emerged as a promising architecture in the realm of intelligent communication paradigms. SemCom involves extracting and compressing the core information at the transmitter while enabling the receiver to interpret it based on established knowledge bases (KBs). This approach enhances communication efficiency greatly. However, the open nature of wireless transmission and the presence of homogeneous KBs among subscribers of identical data type pose a risk of privacy leakage in SemCom. To address this challenge, we propose to leverage the simultaneous transmitting and reflecting reconfigurable intelligent surface (STAR-RIS) to achieve privacy protection in a SemCom system. In this system, the STAR-RIS is utilized to enhance the signal transmission of the SemCom between a base station and a destination user, as well as to covert the signal to interference specifically for the eavesdropper (Eve). Simulation results demonstrate that our generated task-level disturbance outperforms other benchmarks in protecting SemCom privacy, as evidenced by the significantly lower task success rate achieved by Eve

Photonic Hook-Assisted Contrast-Enhanced Super-Resolution Imaging Using Janus Microspheres

Microsphere-assisted imaging is a promising label- free super-resolution imaging technique. Its performance is sig- nificantly affected by the photonic nanojet (PNJ) of microspheres. Recently, a new type of curved PNJ, i.e. the photonic hook (PH), was discovered, which shows promising potential for various applications. This Letter presented a contrast-enhanced super- resolution imaging technique utilizing the PHs generated by Janus microspheres. We demonstrated that the Janus micro- spheres can be fabricated using a one-step deposition process, they exhibit superior imaging performance to pristine micro- spheres, and their field-of-view and imaging contrast can be easily adjusted by changing the coating thickness. In addition, we demonstrated that the imaging contrast of Janus microspheres can be further enhanced by using polarized illumination

Focusing light with a metal film coated patchy particle

Microsphere-assisted super-resolution imaging is a promising technique that can significantly enhance the resolution of conventional optical microscopes. The focus of a classical microsphere is called photonic nanojet, which is a symmetric high-intensity electromagnetic field. Recently, patchy microspheres have been reported to have superior imaging performance than pristine microspheres, and coating microspheres with metal films leads to the formation of photonic hooks, which can enhance the imaging contrast of microspheres. Understanding the influence of metal patches on the near-field focusing of patchy particles is important for the rational design of a nanostructured microlens. In this work, we theoretically and experimentally showed that the light waves can be focused and engineered using patchy particles. When coating dielectric particles with Ag films, light beams with a hook-like structure or S-shaped structure can be generated. Simulation results show that the waveguide ability of metal films and the geometric asymmetry of patchy particles cause the formation of S-shaped light beams. Compared with classical photonic hooks, S-shaped photonic hooks have a longer effective length and a smaller beam waist at far-field region. Experiments were also carried out to demonstrate the generation of classical and S-shaped photonic hooks from patchy microspheres

Effect of tea polyphenols on intestinal barrier and immune function in weaned lambs

IntroductionThe purpose of this study was to explore the effects of tea polyphenols on growth performance, cytokine content, intestinal antioxidant status and intestinal barrier function of lambs, in order to provide reference for intestinal health of ruminants.MethodsThirty weaned lambs (average initial weight 9.32 ± 1.72 kg) were randomly divided into five groups with six lambs in each group. The control group did not add anything but the basic diet mainly composed of Pennisetum and Corn, and the other four groups added 2, 4, 6 g/kg tea polyphenols and 50 mg/kg chlortetracycline to the basic diet, respectively. The experiment lasted for 42 days.ResultsDietary tea polyphenols improved the growth and stress response and reduced intestinal permeability of lambs (p > 0.05), while CTC did not affect the final lamb weight (p > 0.05). Both tea phenols and CTC significantly reduced inflammatory factors and enhanced the immune system (p > 0.05). Dietary tea polyphenols increased villus height, villus height/crypt depth, secretory immunoglobulin A (p > 0.05), and antioxidant enzymes, while decreasing MDA and apoptosis in the intestine (p > 0.05). However, compared with other groups, the content of T-AOC in jejunum did not change significantly (p > 0.05). Tea polyphenols also increased claudin-1 levels in the duodenum, jejunum, and ileum more than CTC (p > 0.05). CTC had a limited effect on the mRNA expression of Occludin and ZO-1, while tea polyphenols increased these in both the duodenum and ileum (p > 0.05).ConclusionThis study demonstrated that tea polyphenols can effectively improve the intestinal barrier of weaned lambs, and that they have anti-inflammatory and antioxidant effects similar to those of antibiotics. Thus, tea polyphenols could be used to replace antibiotics in ensuring safety of livestock products and in achieving the sustainable development of modern animal husbandry

Association Between Cancer Prevalence and Different Socioeconomic Strata in the US: The National Health and Nutrition Examination Survey, 1999–2018

BackgroundInequality in health outcomes in relation to Americans' socioeconomic status (SES) is rising. American Cancer Society depicts that the most common cancers are diagnosed in men and women in 2021. We aim to study socioeconomic inequalities in related cancers to investigate whether the cancer prevalence differs within the family income to poverty ratio (PIR).MethodsThe study investigated data from adults aged 20–85 years participated in the 1999–2018 National Health and Nutrition Examination Survey (NHANES) who had complete data available on PIR and cancer or malignancy information (n = 49,720). Participants were stratified into 3 categories of PIR: high income (PIR ≥ 4), middle income (>1 and <4), or at or below the federal poverty level (≤1).ResultsThe prevalence of prostate cancer was higher in the middle-income (3.61% [n = 464]) and high-income groups (3.36% [n = 227]) than in the low-income group (1.83% [n = 84], all p < 0.001). The prevalence of breast cancer was higher in middle-income (2.86% [n = 390]) and high-income participants (3.48% [n = 218]) than in low-income participants (2.00% [n = 117], all p < 0.001). Compared with the low-income group in men (0.48% [n = 22]), a higher prevalence of colon and rectum cancer occurs in the middle-income (0.87% [n = 112], p = 0.012) and high-income groups (0.89% [n = 58], p = 0.018). The prevalence of lung cancer in women was lower in high-income participants than middle-income participants (0.10% [n = 6] vs. 0.29% [n = 39], p = 0.014).ConclusionsIncreasing disparities in cancer prevalence were identified across all socioeconomic categories analyzed in this study. To ensure the sustainable development goals, it is a global health priority to understand inequalities in health and to target interventions accordingly

A hydride-induced-reduction strategy for fabricating palladium-based core-shell bimetallic nanocrystals

Zheng, NF (通讯作者)One key challenge in making high-quality bimetallic nanocrystals is to prevent self-nucleation of individual metal components. We report in this work an effective seeded growth strategy that uses activated hydrogen atoms as the reducing agent to prepare core-shell bimetallic nanocrystals. In the developed method, Pd nanocrystals serve as the seed and catalyst as well to activate H-2 for the reductive deposition of Ag. The unique feature of the developed method is that the activated hydrogen atoms are confined on the surface of the Pd seeds. Consequently, the self-nucleation of Ag is effectively inhibited so that the deposition of Ag occurs only on Pd. The mechanism studies reveal that reductive growth of Ag on Pd seeds proceeds until the Pd surface is fully covered by Ag. The Ag/Pd ratio in the prepared Pd@Ag nanocrystals is readily fine-tuned by the amount of AgNO3 or H-2. The method is effective for depositing Ag on Pd nanocrystal seeds with different morphologies such as nanosheets, nanocubes, tetrahedra and nanowires. More importantly, the deposition of Ag on Pd nanowires allows preparation of flexible transparent electrode material with sheet electronic conductivity of 271 S sq(-1) at a transmittance of over 90%.MOST of China 2011CB932403 2014CB932004 NSFC of China 21131005 2133300

Shape-Controlled Synthesis of Surface-Clean Ultrathin Palladium Nanosheets by Simply Mixing a Dinuclear Pd-I Carbonyl Chloride Complex with H2O

通讯作者地址: Zheng, NF (通讯作者) Xiamen Univ, State Key Lab Phys Chem Solid Surfaces, Collaborat Innovat Ctr Chem Energy Mat, Xiamen 361005, Peoples R China.MOST of China 2011CB932403 ,2009CB930703 ,NSFC 21131005 ,21021061 ,20925103 ,2092300

Multi-site, Multi-domain Airway Tree Modeling (ATM'22): A Public Benchmark for Pulmonary Airway Segmentation

Open international challenges are becoming the de facto standard for assessing computer vision and image analysis algorithms. In recent years, new methods have extended the reach of pulmonary airway segmentation that is closer to the limit of image resolution. Since EXACT'09 pulmonary airway segmentation, limited effort has been directed to quantitative comparison of newly emerged algorithms driven by the maturity of deep learning based approaches and clinical drive for resolving finer details of distal airways for early intervention of pulmonary diseases. Thus far, public annotated datasets are extremely limited, hindering the development of data-driven methods and detailed performance evaluation of new algorithms. To provide a benchmark for the medical imaging community, we organized the Multi-site, Multi-domain Airway Tree Modeling (ATM'22), which was held as an official challenge event during the MICCAI 2022 conference. ATM'22 provides large-scale CT scans with detailed pulmonary airway annotation, including 500 CT scans (300 for training, 50 for validation, and 150 for testing). The dataset was collected from different sites and it further included a portion of noisy COVID-19 CTs with ground-glass opacity and consolidation. Twenty-three teams participated in the entire phase of the challenge and the algorithms for the top ten teams are reviewed in this paper. Quantitative and qualitative results revealed that deep learning models embedded with the topological continuity enhancement achieved superior performance in general. ATM'22 challenge holds as an open-call design, the training data and the gold standard evaluation are available upon successful registration via its homepage.Comment: 32 pages, 16 figures. Homepage: https://atm22.grand-challenge.org/. Submitte