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Objective: To investigate the relationship between congenital umbilical–portal–systemic venous shunt (UPSVs) and fetal outcome. Methods: The ultrasonographic and genetic characteristics of 11 cases of UPSVS were retrospectively analyzed and followed up to postnatal. Results: Four cases of ductus venosus -- systemic shunt (DVSS), one case of extrahepatic portal -- systemic shunt (EHPSS), and one case of umbilical systemic shunt (USS) combined with intrahepatic portal-systemic shunt (IHPSS), six cases of intrahepatic portal-systemic shunt (IHPSS) were observed. chromosomal abnormalities were observed in 9.1% (1/11), other ultrasonic abnormalities in 54.5% (6/11), cardiothoracic ratio increase in 45.5% (5/11), fetal growth restriction in 36.4% (4/11), edema was in 9.1% (1/11) and live birth was in 72.7% (8/11). Conclusion: The incidence of IHPSS is the highest and the outcome is the best. Shunt of DVSS and IHPSS can be closed spontaneously after birth. When the prenatal diagnosis is congenital UPSVs, chromosomal abnormalities and other ultrasonic abnormalities should be required further examination, and the growth and development of the fetus should be closely monitored.

Terahertz pulses are applied as an all-optical bias to ferroelectric thin-film BiFeO3 while monitoring the time-dependent ferroelectric polarization through its nonlinear optical response. Modulations in the intensity of the second harmonic light generated by the film correspond to on-off ratios of 220× gateable on femtosecond timescales. Polarization modulations comparable to the built-in static polarization are observed.

In 1928, Dirac proposed a wave equation to describe relativistic electrons.sup.1. Shortly afterwards, Klein solved a simple potential step problem for the Dirac equation and encountered an apparent paradox: the potential barrier becomes transparent when its height is larger than the electron energy. For massless particles, backscattering is completely forbidden in Klein tunnelling, leading to perfect transmission through any potential barrier.sup.2,3. The recent advent of condensed-matter systems with Dirac-like excitations, such as graphene and topological insulators, has opened up the possibility of observing Klein tunnelling experimentally.sup.4-6. In the surface states of topological insulators, fermions are bound by spin-momentum locking and are thus immune from backscattering, which is prohibited by time-reversal symmetry. Here we report the observation of perfect Andreev reflection in point-contact spectroscopy--a clear signature of Klein tunnelling and a manifestation of the underlying 'relativistic' physics of a proximity-induced superconducting state in a topological Kondo insulator. Our findings shed light on a previously overlooked aspect of topological superconductivity and can serve as the basis for a unique family of spintronic and superconducting devices, the interface transport phenomena of which are completely governed by their helical topological states. Perfect transmission of electrons through a finite potential barrier between a normal metal and a topological superconducting state is demonstrated, as evidenced by an exact doubling of conductance in point contact measurements., Author(s): Seunghun Lee [sup.1] [sup.2] , Valentin Stanev [sup.1] [sup.2] [sup.3] , Xiaohang Zhang [sup.1] [sup.2] , Drew Stasak [sup.1] , Jack Flowers [sup.1] , Joshua S. Higgins [sup.2] [sup.4] [...]

Animating equity in teaching and learning depends on teacher dispositions—orientations to self, others, and society that underlie how we think and act. Teacher dispositions are virtues or qualities of moral character that modify the ways we interact with students and educator colleagues. Although interest in "measuring to improve" teaching and teacher education has grown recently, most measures lack validity evidence for practical usefulness. Integrating Messick's "unified validity framework" with Janssen et al.'s notion of "practicality" (as face validity), we find through an iterative, mixed-methods analysis of interviews with equitable educators and survey responses from teacher candidates that incorporating recognizability, relevance, and feasibility concerns of equity disposition concepts (i.e., Social Awareness, Meekness, Advocacy for Students) within survey items enhances item-to-factor structure of a self-report measure. We discuss implications (a) to develop and appraise formative measures and (b) to support teacher learning and development to become equitable educators. [ABSTRACT FROM AUTHOR]

To obtain optimal luminescence, 0.12 g of GdVO4:3%Eu3+ nanocrystals (NCs) and different volumes of nitrogen‐doped carbon dots (N‐CDs) crude solution were used as precursors, and the composite synthesized using the hydrothermal deposition method showed optimal luminescence when 11 ml (2.45 mmol) crude solution was used. In addition, similar composites with the same molar ratio as GVE/cCDs(11) were also prepared with the hydrothermal and physical mixing processes. Based on the test results of XRD, XPS, and PL spectra, for the composite GVE/cCDs(11), the highest (lowest) peak intensity of the C–C/C=C (C=O/C=N) bond, which was 1.18 (0.75) times that of GVE/cCDs‐m, indicated most N‐CDs deposition and led to their highest emission intensity under 365 nm excitation, although nitrogen atoms in the composite were shed slightly during the deposition process. Finally, as can be seen from the patterns designed for security applications that the optimally luminescent composite is one of the most promising candidates in the anti‐counterfeiting field. [ABSTRACT FROM AUTHOR]