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1.
iScience ; 27(4): 109545, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38617557

ABSTRACT

Dysregulated macrophage polarization from pro-inflammatory M1 to anti-inflammatory M2 phenotypes underlies impaired cutaneous wound healing. This study reveals Vγ4+ γδ T cells spatiotemporally calibrate macrophage trajectories during skin repair via sophisticated interferon-γ (IFN-γ) conditioning across multiple interconnected tissues. Locally within wound beds, infiltrating Vγ4+ γδ T cells directly potentiate M1 activation and suppress M2 polarization thereby prolonging local inflammation. In draining lymph nodes, infiltrated Vγ4+ γδ T cells expand populations of IFN-γ-competent lymphocytes which disseminate systemically and infiltrate into wound tissues, further enforcing M1 macrophages programming. Moreover, Vγ4+γδ T cells flushed into bone marrow stimulate increased IFN-γ production, which elevates the output of pro-inflammatory Ly6C+monocytes. Mobilization of these monocytes continually replenishes the M1 macrophage pool in wounds, preventing phenotypic conversion to M2 activation. Thus, multi-axis coordination of macrophage activation trajectories by trafficking Vγ4+ γδ T cells provides a sophisticated immunological mechanism regulating inflammation timing and resolution during skin repair.

2.
Science ; 383(6681): 384-387, 2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38271496

ABSTRACT

Collective couplings of atomic dipoles to a shared electromagnetic environment produce a wide range of many-body phenomena. We report on the direct observation of resonant electric dipole-dipole interactions in a cubic array of atoms in the many-excitation limit. The interactions produce spatially dependent cooperative Lamb shifts when spectroscopically interrogating the millihertz-wide optical clock transition in strontium-87. We show that the ensemble-averaged shifts can be suppressed below the level of evaluated systematic uncertainties for optical atomic clocks. Additionally, we demonstrate that excitation of the atomic dipoles near a Bragg angle can enhance these effects by nearly an order of magnitude compared with nonresonant geometries. Our work demonstrates a platform for precise studies of the quantum many-body physics of spins with long-range interactions mediated by propagating photons.

3.
Biomed Eng Online ; 22(1): 96, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37749595

ABSTRACT

Transformers have been widely used in many computer vision challenges and have shown the capability of producing better results than convolutional neural networks (CNNs). Taking advantage of capturing long-range contextual information and learning more complex relations in the image data, Transformers have been used and applied to histopathological image processing tasks. In this survey, we make an effort to present a thorough analysis of the uses of Transformers in histopathological image analysis, covering several topics, from the newly built Transformer models to unresolved challenges. To be more precise, we first begin by outlining the fundamental principles of the attention mechanism included in Transformer models and other key frameworks. Second, we analyze Transformer-based applications in the histopathological imaging domain and provide a thorough evaluation of more than 100 research publications across different downstream tasks to cover the most recent innovations, including survival analysis and prediction, segmentation, classification, detection, and representation. Within this survey work, we also compare the performance of CNN-based techniques to Transformers based on recently published papers, highlight major challenges, and provide interesting future research directions. Despite the outstanding performance of the Transformer-based architectures in a number of papers reviewed in this survey, we anticipate that further improvements and exploration of Transformers in the histopathological imaging domain are still required in the future. We hope that this survey paper will give readers in this field of study a thorough understanding of Transformer-based techniques in histopathological image analysis, and an up-to-date paper list summary will be provided at https://github.com/S-domain/Survey-Paper .


Subject(s)
Image Processing, Computer-Assisted , Learning , Neural Networks, Computer
4.
Phys Rev Lett ; 128(9): 093001, 2022 Mar 04.
Article in English | MEDLINE | ID: mdl-35302810

ABSTRACT

The observation of Pauli blocking of atomic spontaneous decay via direct measurements of the atomic population requires the use of long-lived atomic gases where quantum statistics, atom recoil, and cooperative radiative processes are all relevant. We develop a theoretical framework capable of simultaneously accounting for all these effects in the many-body quantum degenerate regime. We apply it to atoms in a single 2D pancake or arrays of pancakes featuring an effective Λ level structure (one excited and two degenerate ground states). We identify a parameter window in which a factor of 2 extension in the atomic lifetime clearly attributable to Pauli blocking should be experimentally observable in deeply degenerate gases with ∼10^{3} atoms. We experimentally observe a suppressed excited-state decay rate, fully consistent with the theory prediction of an enhanced excited-state lifetime, on the ^{1}S_{0}-^{3}P_{1} transition in ^{87}Sr atoms.

5.
J Colloid Interface Sci ; 606(Pt 1): 898-911, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34481249

ABSTRACT

Developing photocatalysts that are inexpensive and efficient in degrading pollutants are essential for environmental remediation. Herein, a novel system of perylene diimide (PDI)/CuS p-n heterojunction was synthesized by a two-step self-assembly strategy for removal of tetracycline in waste water. Results showed that PDI/CuS-10% exhibited highest photocatalytic behavior. The apparent rate constants for tetracycline (TC) degradation for the blend were 5.27 and 2.68 times higher than that of CuS or PDI, respectively. The enhancement of photocatalytic activity was mainly attributed to the π-π stacking and p-n junction, which can accelerate the separation of the photo-generated h+-e- pairs. Besides, the light absorption of PDI/CuS from 800 to 200 nm was significantly enhanced and the absorption edge even reached the near-infrared region, which also played an important role in providing desired photocatalytic properties. Surprisingly, PDI/CuS could maintain high catalytic activity even after 5 cycles under simulated conditions, indicating that the composite had high potential for practical applications. Owing to high efficiency, low cost and wide application range, the PDI/CuS nanocomposites are promising candidates for environmental remediation.


Subject(s)
Environmental Restoration and Remediation , Perylene , Copper , Light
6.
Science ; 374(6570): 979-983, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34793223

ABSTRACT

Transition rates between coupled states in a quantum system depend on the density of available final states. The radiative decay of an excited atomic state has been suppressed by reducing the density of electromagnetic vacuum modes near the atomic transition. Likewise, reducing the density of available momentum modes of the atomic motion when it is embedded inside a Fermi sea will suppress spontaneous emission and photon scattering rates. Here we report the experimental demonstration of suppressed light scattering in a quantum degenerate Fermi gas. We systematically measured the dependence of the suppression factor on the temperature and Fermi energy of a strontium quantum gas and achieved suppression of scattering rates by up to a factor of 2 compared with a thermal gas.

7.
Clin Res Hepatol Gastroenterol ; 38(2): 172-80, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24316043

ABSTRACT

OBJECTIVE: Several studies have indicated an association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and the risk of hepatocellular carcinoma (HCC). However, the conclusions are inconsistent. Therefore, a meta-analysis was performed. METHODS: Databases like Pubmed, EMBASE, and EBSCO (up to September 2012) were searched to retrieve case-control trials about MTHFR (C677T or A1298C) polymorphisms and HCC. Literatures were independently screened by two researchers according to the inclusion and exclusion criteria. Data were extracted and analyzed by software STATA 11.0. RESULTS: Nine studies were included with 10 datasets and 5132 cases. C677T polymorphism was associated with HCC risk in a heterozygous model (TT vs. CT: OR=1.20, 95% CI: 1.02-1.40). For the A1298C polymorphism, a significantly decreased HCC risk was found in the dominant, heterozygous and homozygous models (CC vs. AA+AC: OR=0.52, 95% CI: 0.33-0.80; CC vs. AC: OR=0.50, 95% CI: 0.32-0.79; CC vs. AA: OR=0.52, 95% CI: 0.33-0.81). Subgroup analysis stratified by ethnicity and type of control further indicated decreased HCC risks in Asians (CC vs. AA+AC: OR=0.47, 95% CI: 0.26-0.84; CC vs. AC: OR=0.41, 95% CI: 0.24-0.71; CC vs. AA: OR=0.46, 95% CI: 0.27-0.78), studies with controls of healthy people (CC vs. AA: OR=0.54, 95% CI: 0.31-0.93; CC vs. AC: OR=0.54, 95% CI: 0.31-0.94; CC vs. AA+AC: OR=0.55, 95% CI: 0.32-0.94), and controls of non-HCC patients (CC vs. AC: OR=0.43, 95% CI: 0.19-0.96). CONCLUSIONS: Homozygous carriers of MTHFR C677T mutation are more susceptible to HCC, but homozygous mutations of MTHFR A1298C may play a protective role for developing HCC.


Subject(s)
Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Genetic , Asian People/genetics , Genetic Predisposition to Disease , Homozygote , Humans , Mutation
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