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A 10-year-old girl presented with obvious cyanosis, and the saturation of arterial blood oxygen (SpO2) was decreased to 60.5% in the outpatient examination. Computed tomography angiography (CTA) and echocardiography suggested congenitally corrected transposition of the great arteries (ccTGAs), membranous ventricular septal aneurysm (MVSA), atrial septal defect (ASD), severe pulmonary stenosis (PS), and severe tricuspid regurgitation (TR). Due to the complex pathological anatomical structures, the three-dimensional printed model was used for preoperative assessment. After a comprehensive evaluation was completed, the operation was performed by physiological correction under cardiopulmonary bypass, including the resection of MVSA, repair using the bovine pericardial patch for ASD, and linear valvuloplasty of the tricuspid valve. Due to the special anatomical structures of ccTGA, PS was treated by extracardiac pipe technique. After the operation, the patient recovered well, cyanosis disappeared, SpO2 was up to 96%, and the extracardiac pipe was well-functioning without regurgitation or obstruction.

Abstract. Objective:. To evaluate the predictive ability of neonate condition through the traditional parameters and artery umbilical cord blood gas (aUCBG). Methods:. A prospective cohort study was conducted in obstetrics and gynecology department between October 2017 and August 2018 at Tongji Hospital in Wuhan, China, and 360 aUCBG samples were collected. The average age of pregnant women was (29.50 ± 4.42) years, range from 19 to 48 years old. The gestational age range from 28+4 weeks to 41+3 weeks at admission. Logistic regression and area under the curve (AUC) from Receiver operating characteristic curves were used to identify risk factors, such as, premature rupture of membranes (PROM), high blood pressure, premature delivery (PD), low 1-minute Apgar scores (Apgar 1), low 5-minute Apgar scores (Apgar 5), pH, base excess, bicarbonate, neonatal blood sugar (NBS), and so on, to predict neonatal condition and evaluate the predictive ability of traditional and aUCBG parameters. Results:. In all cases, PROM, PD, Apgar 1, Apgar 5, pH, base excess, bicarbonate, total carbon dioxide, and neonatal blood sugar were risk factors and were associated with poor condition of neonate. Apgar 1 were an independent risk factor. Combined traditional and aUCBG parameters had higher AUC of 0.895 (95% confidence interval (CI): 0.830–0.960, P

Abstract Nodal chain (NC) semi-metals have the degeneracy of interlacing rings in their band structure in momentum space. With the projection of degenerate rings towards crystal boundaries, there is a special type of surface dispersion appearing at surface Brillouin zone and termed drumhead surface state (DSS). Previously, experimental investigations on photonic NC and DSS have been done on metallic photonic crystals at microwave frequencies. However, far-field detection of DSS and its coupling to radiative modes in free space have not been studied. In the work, we analyze the photonic DSS in a metallic lattice by angle-resolved far-field reflection measurement and numerical simulation at terahertz (THz) frequencies, and reveal its flatness and boundness in band structure, even in the radiation continuum. Particularly, the DSS band can be tuned being from negatively dispersive via flat to positively dispersive by a single surface parameter, and the DSS at Γ point in surface Brillouin zone is in fact a symmetry-protected bound state in the continuum. Our results might have some potential applications towards THz photonics.

The emerging technology of vehicle-to-vehicle (V2V) communication, vehicle-to-infrastructure (V2I) communication makes it possible for vehicles to sense the environment information, which can be exploited to assist the vehicle in cooperative motion planning. In this paper, we focus on the cooperative trajectory planning of lane changes for connected and automated vehicles (CAVs). The proposed model considers the traffic scene with multiple mandatory lane change demands and completes the trajectory planning for vehicles by taking the safety and efficiency into consideration. The model solves two critical issues: the vehicle grouping and the motion planning. In the first issue, CAVs in the cooperative zone are divided into different groups. Then the problem is simplified and divided into several subproblems. In the second issue, the trajectory planning is conducted in each group. Trajectories are generated for vehicles with and without lane change demands. Besides, these two steps are iterated and updated in the fixed time interval, which makes full use of the dynamic cooperation ability of vehicles. Extensive simulation tests are conducted to validate the performance of the model. Results show that the cooperation of vehicles realizes safe and effective lane changes.

Exceptional points in non-Hermitian systems can enhance the performance of optical sensors. Here, Wang et al. demonstrate theoretically and experimentally that higher-order exceptional points, which would allow for yet higher sensitivities, can be realized in simple photonic resonator chains.

In this work, we utilize a dynamic Bayesian network for an inferential analysis of driving-related risks based on our assessment of real-world driving data. On-road driving tests are carried out to gather and analyze data to identify different evaluation indicators of driving-related risks. These indicators include the distance between vehicles, acceleration, steering entropy, visual distraction duration, visual glance speed, and blink frequency. Moreover, these indicators are processed to build a driving-related risk evaluation model based on the dynamic Bayesian network. The validity of this model is further tested by experimental data. The results show that this model can achieve a reasonable quantitative evaluation of driving-related risks. Vehicle operation-related risks can be further divided into four levels of safety, namely, levels I to IV. The lowest risk is observed at level I, whereas level IV has the highest risk. Among the indicators for risk evaluation, the distance between vehicles is the most sensitive control indicator of vehicle operation-related risks. The research findings provide various methodologies that could be utilized for evaluation and early warning of driving-related risks. Thus, a theoretical foundation to seek solutions for the safety of advanced driving assistance system is formed.

We have fabricated a three-dimensional (3D) microlattice, composed of orthogonal polymer rods along three dimensions and featured with a sub-millimeter scale size, with a photopolymerizing 3D printer. The reflection and transmission spectra of the microlattice have been measured in terahertz time-domain spectroscopy and compared with numerical simulations. Due to Debye relaxation loss of the constituent photopolymer, the microlattice gives rise to absorption in the measured frequencies. In particular, the absorption modulation is observed across the bandgap, corresponding to the lower/upper band edges, and is a straightforward manifestation of the Borrmann effect.

In this paper, we study the secure beamforming (BF) and artificial noise (AN) techniques for a cognitive satellite-terrestrial network, where a satellite system termed as the primary network under the interception of multiple unauthorized eavesdroppers shares the spectrum of resources with multi-cell secondary terrestrial networks. The design objective is to minimize the total transmit power on board the satellite and multiple terrestrial base stations (BSs) while meeting the secrecy rate constraint of the primary satellite user along with the signal-to-interference-plus-noise ratio constraints of secondary terrestrial users. When exact channel state information at the satellite and terrestrial BS is perfectly known, a zero-forcing scheme is first presented to obtain a sub-optimal solution with low complexity. Next, we propose a semi-definite relaxation-based iterative algorithm together with a golden section search method to achieve the optimal solution. Moreover, a joint BF and AN scheme is further explored to provide the additional degree-of-freedom against illegitimate eavesdropping. Eventually, numerical simulations are given to confirm the validity of the proposed schemes as well as the performance improvements compared with the existing approaches.

Reflection due to impedance mismatch at interfaces of different materials is undesired in many THz applications including THz communication, spectroscopy and imaging. In this work, we theoretically and experimentally demonstrate a type of THz photonic crystals exhibiting wide-angle impedance matching property with free space. The reflection as well as the reflection-induced Fabry–Pérot resonances are efficiently suppressed in a relatively broad spectrum. A sample is fabricated using high-resistance silicon and polyethylene terephthalate films. By using THz time domain spectroscopy, we have clearly observed high transmittance and suppression of Fabry–Pérot resonances for a wide range of incident angles (0°–60°) and a relatively broad spectrum (0.26–0.55 THz) in both polarizations. Our work opens a general approach for improvement of transmission and imaging quality in THz spectroscopy.

The advance of research on 2D transition metal carbides, carbonitrides, and nitrides (collectively known as MXenes) has progressed rapidly since the introduction of Ti3C2 in 2011. Nowadays the number of MXene synthesized in lab has reached more than 20, while there are currently about 20 theoretically predicted structures. In this study, we calculate the electromagnetic interference shielding effectiveness of a series of MXene films in theory and find that the results are in good agreement with the measured data. From this, we can use this method to calculate electromagnetic properties of all kinds of 2D material films which are similar to Mxenes.

According to the theory, an ultrathin conductive film can achromatically dissipate electromagnetic waves with frequency ranging from radio to terahertz. A moderate absorption effect, which gives rise to a maximal absorbance of 50%, can be found if an impedance matching condition is satisfied. We have experimentally demonstrated the frequency-irrelevant, maximal absorption by employing a conductive nanofilm and launching terahertz waves at Brewster angle when the sheet (square) resistance of the film meets the impedance matching condition. In the entire terahertz spectral range covered by our experiments, the frequency-independent optical properties were consistent with the theoretical calculations.

We have investigated the photonic Wannier-Stark ladder in the system of coupled electromagnetic cavities, which consists of a stack of metallic plates structured with subwavelength apertures and where the tilted potential effect is mimicked by imposing the gradient variation of refractive index. Making an analogy to its quantum counterpart and assuming the translational property of its solutions, we have shown the photonic ladder has the eigenenergies, that is, frequencies, in a geometrical series. Within the approximation of small gradient, the ladder states manifest the equidistant frequency spacing in the spectrum. By both analytical derivation and numerical simulation, we have illustrated the geometrically progressed energies of the photonic Wannier-Stark ladder.

Direct injection of murine K-1735 melanoma cells into the subcutis, lung, or brain of syngeneic mice produces amelanotic tumors, whereas intravenous injection into the lateral tail vein or internal carotid artery produces both amelanotic and melanotic foci in the lung and the brain respectively. We hypothesized that loss of adhesion in the circulation may contribute to the melanogenic phenotypes of cells. To test this, we used enforced suspension culture of K-1735 cells by consistent rotating culture of K-1735 cells. We found that the expression of the microphthalmia transcription factor (MITF) and melanin-stimulating hormone receptor (MSHR) were upregulated in cells growing in suspension and were accompanied by inhibitions of AKT and ERK, which were reversed in cells upon regrowth as an adherent monolayer. Inhibition of the AKT pathway was responsible for MITF induction by suspension culture. Stable expression of constitutively active AKT significantly repressed the melanogenesis of K-1735 cells injected via circulation. An amelanotic clone of K-1735 cells was resistant to suspension cultureinduced MITF, although the inhibition of AKT pathway was intact. Collectively, these data suggest that the inhibition of AKT pathway due to loss of adhesion within the circulation renders a subpopulation of K-1735 cells to produce melanin.

Spatially mapping electromagnetic fields in the quasi-two-dimensional field mapper (a parallel plate waveguiding system; Justice et al. (2006)) for characterizing metamaterial devices, especially those integrating the metal boundary, may encounter troubles including electromagnetic leakage caused by the air gap and energy guiding along finitely high metal walls. To eradicate them, a moving contact approach is proposed. The physical air gap between the mobile metal walls and the stationary upper plate of the mapper is closed, while their relative movement is still allowed during the field mapping. We demonstrate the method of closing the gap by mapping the E-field distribution in a rectangular waveguide.

We study the absorption properties of ultrathin conductive films in the microwave regime, and find a moderate absorption effect which gives rise to maximal absorbance 50% if the sheet (square) resistance of the film meets an impedance matching condition. The maximal absorption exhibits a frequency-independent feature and takes place on an extremely subwavelength scale, the film thickness. As a realistic instance, ∼5 nm thick Au film is predicted to achieve the optimal absorption. In addition, a methodology based on metallic mesh structure is proposed to design the frequency-independent ultrathin absorbers. We perform a design of such absorbers with 50% absorption, which is verified by numerical simulations.

Abstract The evolution process of regional space between coastal and interior areas is a direct manifestation of the theory of regional economic development imbalance. Previous research has neglected the impacts of population, and economic factor flows on the balance of regional development between coastal and interior areas. By constructing global coastal-interior regional population-economic panel data and a threshold effect model, this study explored regional development imbalance on the largest scale between global coastal and interior areas. The results indicated that the global population is unevenly distributed across coastal and interior areas. Global coastal areas (accounting for 18.43% of the world’s landmass) are occupied by ~52.8% of the global population; meanwhile, ~23% of the global population is concentrated in the ‘near region’ subtropical zone extending from 10° to 30° north and south in latitude. The economic pattern between global coastal and interior areas has become more balanced, and the per capita GDP gap between the two sub-regions has decreased from 2.08 times to 1.78 times during the study period (2000 to 2018). Nevertheless, the evolutionary process of population factors lags behind that of economic factors. Apart from Africa, the development gap of intercontinental coastal and interior areas has been converging to varying degrees. Adjusting regional per capita income levels and population-economic density can promote balanced development between coastal and interior areas both globally and across continents. These findings may contribute to the implementation of effective policies for spatial balance and sustainable development in coastal and interior areas across multiple spatial scales. This study extends the theoretical research on uneven regional growth and provides a foundation for further research to achieve the goals of the UN 2030 Agenda for Sustainable Development.

The effective utilization of urban land plays a significant role in achieving the 11th goal focuses on Sustainable cities and communities. China's national special economic parks (NSEP) have undergone a remarkable process of urbanization over the past 40 years, and the land for future development is becoming increasingly scarce. In this study, a convolutional neural network with attention mechanisms was proposed for extracting built-up area boundaries of NSEP; Additionally, the urban land use efficiency (ULUE) was estimated by combining multi-source nighttime light image and statistical data from yearbooks. Furthermore, we integrate a data-driven model for predicting ULUE. The empirical research involves a comprehensive analysis of the spatial characteristics of urban land expansion by using the Taylor index and spatial analysis. This study reveals the following findings: ① Convolutional Neural Networks based on attention mechanisms can achieve high-precision extraction of urban boundaries with a Kappa value exceeding 0.92; ②There is a significant positive correlation between the brightness of nighttime light imagery and the GDP of the secondary and tertiary industries; ③ ULUE exhibits evident dependence on urban scale; ④ The density-nuclear density curve features of ULUE with the peak gradually decreasing, which indicates a continuous expansion of the distribution range of land use efficiency. This research framework aims to provide the support for the scientific management and sustainable utilization of urban land while serving as empirical reference for future policy formulation and planning.

Abstract It is well established that nighttime light brightness value, which is measured from satellites, correlates with economic prosperity across the globe. Researchers have diverged over whether economic factors cluster in coastal areas or move to interior areas. By using nighttime light data and applying the random forest algorithm to measure the proportion of global “near regions” GDP, it was seen that global GDP decreased from 67.25% in 2000 to 63.02% in 2018. This research reveals that under the continuous promotion of economic globalization, there is still a spatial imbalance of economic development between global “near regions” and “far regions”; however, economic factors are gradually shifting to interior areas and forming a “coastal remoteness” evolution pattern. Within the intercontinental range, there are obvious differences in the evolution patterns and spatial structure of economic development between the sub-regions. The reduction of overseas transportation costs and diseconomies of scale are the primary reasons for the evolution of “coastal remoteness” in global economic development. Our findings can facilitate future policymaking and the management of global coastal and interior areas, as well as establish new horizons for relevant research topics within the context of land and marine-coordinated development.