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• Using phase-change material Ge 2 Sb 2 Se 4 Te 1 (GSST) as the pattern layer, calcium fluoride as the substrate, the metasurface can be switched from highly transmission (90 %) mode to perfect absorption (99 %) mode in the NIR (1.55 µm) wavelength region, when the GSST layer is transformed from the amorphous to crystalline state. • The new design using the GSST layer with a single hole as the metasurface shows that the transmission of the structure (90%) is considerably improved compared to previous work when the GSST layer is in amorphous state. • This reconfigurable metasurface based on phase change materials shows great potential as a platform for the development of other reconfigurable metasurface devices, paving the way for the design of new integrated devices and systems in optical fiber communication at 1.55 µm wavelength region and other NIR applications. Reconfigurable metasurfaces provide a new way for applications requiring dynamic tunability, such as focusing lenses, holographic displays, optical switch and so on. In this paper, a reconfigurable bi-functional metasurface is proposed. Using phase-change material Ge 2 Sb 2 Se 4 Te 1 (GSST) as pattern layer, calcium fluoride as substrate, the metasurface can be switched from highly transmission (90 %) mode to perfect absorption (99 %) mode in the 1.55 μm wavelength region, when the GSST layer is transformed from the amorphous to crystalline state. And the response of this metasurface is independent of the polarization of incident wave. Our novel design has potential significance in the design of infrared switching devices in the future. [ABSTRACT FROM AUTHOR]

• A novel kind of graphene integrated dual-polarization rasorber is proposed in the terahertz regime. • Ultra-wideband impedance matching with functionalities of both absorption and transmission is achieved from 1.34 to 3.13 THz. • The outstanding performance of both absorption and transmission can be guaranteed with the incident angles increased up to 40°. • The rasorber has advantages of avoiding 3-D hollow lattices/air spacer and welding multiple lumped resistors. In this letter, a novel kind of graphene integrated dual-polarization rasorber is proposed in the terahertz regime. This two-dimensional rasorber is cascaded a top lossy layer, a middle dielectric spacer and a lossless layer at the bottom. Ultra-wideband impedance matching with functionalities of both absorption and transmission is achieved from 1.34 to 3.13 THz. The broadband absorptive characteristic which mainly originates from strong electric field confinement is produced by integrating graphene flakes into cross-frame resonators. On the other hand, the transmission band with low insertion loss is obtained using a complementary square ring resonator (CSRR). The proposed rasorber exhibits a good absorption performance from 1.27 to 2.43 THz and a low insertion loss at 2.8 THz. Oblique incidence stability and tunable absorption by varying chemical potential of graphene are also proved. The rasorber has further advantages of avoiding 3-D hollow lattices/air spacer and welding multiple lumped resistors, thereby greatly improving the planar integration of the structure in photovoltaic devices. [ABSTRACT FROM AUTHOR]

Let X be an RD-space. In this paper, the authors establish the boundedness of the commutator T f = bT f − T( bf) on L, p ∈ (1,∞), where T is a Calderón-Zygmund operator related to the admissible function ρ and b ∈ BMO( X) ⊇ BMO( X). Moreover, they prove that T is bounded from the Hardy space H ( X) into the weak Lebesgue space L( X). This can be used to deal with the Schrödinger operators and Schrödinger type operators on the Euclidean space ℝ and the sub-Laplace Schrödinger operators on the stratified Lie group $\mathbb{G}$. [ABSTRACT FROM AUTHOR]

Abstract: The features of surface wave modes in the fiber composed of single-negative (SNG) metamaterials have been investigated. The geometric and frequency dispersion of surface wave modes in SNG fibers are considered. The dispersion curves, energy flux and power of lower-order (m=0,1) surface wave modes are presented. Some interesting properties, such as totally backward or forward wave, zero power, sign-varying energy flux in the core or cladding region, single mode operation, are found. [Copyright &y& Elsevier]

The expression status of CD74 in breast cancer stem cells and its clinical implications was evaluated in order to lay a foundation for managing breast cancer. Five hundred and eighty breast cancer specimens were enrolled in the study. The relationship between the CD74 protein and clinicopathological parameters as well as prognosis was subsequently determined. In total, 468 (80.69 %) of the 580 breast cases showed CD74-positive expression. After universal analysis, CD74 was observed to be related to lymph node metastasis and triple-negative breast cancer ( P = 0.01 and 0.001). Moreover, CD74 expression has a line correlation with lymph node metastasis and triple-negative breast cancer ( P = 0.02 and 0.001). Furthermore, periostin was shown to attain a significantly more distant liver metastasis and worse disease-specific survival than those with none or low-expressed CD74 protein ( P = 0.001). In the Cox regression test, CD74 protein was detected as an independent prognostic factor ( P = 0.001). CD74 is consistently expressed in triple-negative subgroups of breast cancer and might be a new potential marker for triple-negative breast cancer. [ABSTRACT FROM AUTHOR]

Objective: Comparative study of racial-ethnic (RE) gestational age (GA) mean birth-weight (MBW) differences for 1968-1994. Study Design: Descriptive statistical analyses of 314,633 State of Hawai'i live birth certificates: birth-weights of 500-5000 grams, gestational ages 24-42 weeks, and recorded Caucasian, Chinese, Filipino, Hawaiian, Japanese, Samoan, and Other RE parentage. Multiple regression analyses of single infant birth records were performed to adjust birth-weight for selected covariates and assess the independent effects of maternal and paternal RE on MBW. Results: Samoans consistently displayed significantly the largest MBW whether based on single or mixed RE parentage. After covariate adjustment MBW significantly related to Samoan maternal RE followed by Samoan paternal RE. Conclusion: A consistent trajectory of larger MBWs across GA span of 24-42 weeks is associated with the Samoan group. Results support the importance of maternal role in determining birth-weight. Additional data for analysis of birth size and cord blood levels of insulin growth factor and research on genetic and epigenetic questions are warranted. [ABSTRACT FROM AUTHOR]

Fetal growth restriction (FGR) increases the risk for impaired cognitive function later in life. However, the precise mechanisms remain elusive. Using dexamethasone-induced FGR and protein restriction-influenced FGR mouse models, we observe learning and memory deficits in adult FGR offspring. FGR induces decreased hippocampal neurogenesis from the early post-natal period to adulthood by reducing the proliferation of neural stem cells (NSCs). We further find a persistent decrease of Tet1 expression in hippocampal NSCs of FGR mice. Mechanistically, Tet1 downregulation results in hypermethylation of the Dll3 and Notch1 promoters and inhibition of Notch signaling, leading to reduced NSC proliferation. Overexpression of Tet1 activates Notch signaling, offsets the decline in neurogenesis, and enhances learning and memory abilities in FGR offspring. Our data indicate that a long-term decrease in Tet1/Notch signaling in hippocampal NSCs contributes to impaired neurogenesis following FGR and could serve as potential targets for the intervention of FGR-related cognitive disorders. [Display omitted] • FGR mice show decreased hippocampal NSC proliferation and impaired cognition • FGR-induced loss of Tet1 contributes to reduced NSC proliferation • Decreasing Tet1 results in DNA hypermethylation of Notch signaling genes • Restoring Tet1 in the FGR hippocampus rescues neurogenesis and enhances cognition Chen et al. demonstrate that fetal growth restriction (FGR) mice show decreased Tet1 expression, reduced hippocampal NSC proliferation, and impaired cognition in offspring. Increasing Tet1 activates Notch signaling, offsets the decline in neurogenesis, and enhances learning and memory abilities in FGR offspring. [ABSTRACT FROM AUTHOR]

Scalar coupling constant (SCC), directly measured by nuclear magnetic resonance (NMR) spectroscopy, is a key parameter for molecular structure analysis, and widely used to predict unknown molecular structure. Restricted by the high cost of NMR experiments, it is impossible to measure the SCC of unknown molecules on a large scale. Using density functional theory (DFT) to theoretically calculate the SCC of molecules is incredibly challenging, due to the cost of substantial computational time and space. Graph neural networks (GNN) of artificial intelligence (AI) have great potential in constructing molecul ar-like topology models, which endows them the ability to rapidly predict SCC through data-driven machine learning methods, and avoiding time-consuming quantum chemical calculations. With a priori knowledge of angles, we propose a graph angle-attention neural network (GAANN) model to predict SCC by means of some easily accessible related information. GAANN, with a multilayer message-passing network and a self-attention mechanism, can accurately simulate the molecular-like topological structure and predict molecular properties. Our simulations show that the prediction accuracy by GAANN, with the log(MAE) = −2.52, is close to that by DFT calculations. Different from conventional AI methods, GAANN combining the AI method with quantum chemistry theory (Karplus equation) has a strong physicochemical interpretability about angles. From an AI perspective, we find that bond angle has the highest correlation with the SCC among all angle features (dihedral angle, bond angle, geometric angles) about multiple coupling types in the small molecule datasets. [ABSTRACT FROM AUTHOR]