Explore the vast range of titles available.

Numerous optoelectronic devices based on low-dimensional nanostructures have been developed in recent years. Among these, pyramidal low-dimensional semiconductors (zero- and one-dimensional nanomaterials) have been favored in the field of optoelectronics. In this review, we discuss in detail the structures, preparation methods, band structures, electronic properties, and optoelectronic applications (photocatalysis, photoelectric detection, solar cells, light-emitting diodes, lasers, and optical quantum information processing) of pyramidal low-dimensional semiconductors and demonstrate their excellent photoelectric performances. More specifically, pyramidal semiconductor quantum dots (PSQDs) possess higher mobilities and longer lifetimes, which would be more suitable for photovoltaic devices requiring fast carrier transport. In addition, the linear polarization direction of exciton emission is easily controlled via the direction of magnetic field in PSQDs with C3v symmetry, so that all-optical multi-qubit gates based on electron spin as a quantum bit could be realized. Therefore, the use of PSQDs (e.g., InAs, GaN, InGaAs, and InGaN) as effective candidates for constructing optical quantum devices is examined due to the growing interest in optical quantum information processing. Pyramidal semiconductor nanorods (PSNRs) and pyramidal semiconductor nanowires (PSNWRs) also exhibit the more efficient separation of electron-hole pairs and strong light absorption effects, which are expected to be widely utilized in light-receiving devices. Finally, this review concludes with a summary of the current problems and suggestions for potential future research directions in the context of pyramidal low-dimensional semiconductors.

Self-powered ultraviolet (UV) photodetectors have attracted considerable attention in recent years because of their vast applications in the military and civil fields. Among them, self-powered UV photodetectors based on p-n heterojunction low-dimensional nanostructures are a very attractive research field due to combining the advantages of low-dimensional semiconductor nanostructures (such as large specific surface area, excellent carrier transmission channel, and larger photoconductive gain) with the feature of working independently without an external power source. In this review, a selection of recent developments focused on improving the performance of self-powered UV photodetectors based on p-n heterojunction low-dimensional nanostructures from different aspects are summarized. It is expected that more novel, dexterous, and intelligent photodetectors will be developed as soon as possible on the basis of these works.

In the original publication [...]

Large-area oriented ZnO nanoarrays (including nanowire, nanorod, and nanotube) on ITO glass substrates are synthesized via the simple hydrothermal, electrodeposition, and electrochemical etching approach. The morphology of ZnO nanoarrays is controlled by adjusting the reaction temperature, reaction time, and current density. The scanning and transmission electron microscopy (SEM and TEM) results indicate the successful preparation of large-area oriented ZnO nanoarrays with different types, and the energy-dispersive X-microanalysis spectrum (EDS) and X-ray diffraction (XRD) results confirm that the composition of the obtained nanoarrays is ZnO. More importantly, the as-prepared ZnO nanotube arrays are observed with about a 40% increase in ultraviolet absorption intensity compared to the ZnO nanowire/nanorod arrays, due to having larger specific surface areas. The as-prepared different types of ZnO nanoarrays have great potential for applications in low-cost and high-performance optoelectronic devices.

Steel risers are widely used in offshore oil and gas industry. However, the production capacity and depths are limited due to their extreme weight and poor fatigue and corrosion resistance. Nowadays, it is confirmed that fiber reinforced polymer (FRP) composite risers have apparent advantages over steel risers. However, the study of vortex induced vibration (VIV) for composite risers is rarely involved. Three different risers (one steel riser and two composite risers) were compared for their VIV characteristics. The effects of 2D and 3D models and fluid–structure interaction (FSI) were considered. The models of composite risers are established by effective modulus method (EMM) and layered-structure method (LSM). It is found that 2D model are only suitable for ideal condition, while, for real situation, 3D model with FSI has to be considered. The results show that the displacements of the FRP composite risers are significantly larger than those of the steel riser, while the stresses are reversed. In addition, the distributions of the displacements and stresses depend on the geometries, material properties, top-tension force, constraints, etc. In addition, it is obvious that EMM are suitable to study the global working condition while LSM can be utilized to obtain the results in every single composite layer.

Background According to the Global Burden of Disease Study 2017, smoking is one of the leading four risk factors contributing to deaths in China. We aimed to evaluate the associations of smoking with all-cause mortality in a Chinese rural population. Methods Male participants over age 45 ( n  = 5367) from a large familial aggregation study in rural China, were included in the current analyses. A total of 528 former smokers and 3849 current smokers accounted for 10 and 71.7% of the cohort, respectively. Generalized Estimating Equations were used to evaluate the association between baseline smoking status and mortality, adjusting for pertinent covariates. Results There were 579 recorded deaths during the 15-year follow-up. Current smokers (odds ratio [OR],1.60; 95% CI,1.23–2.08) had higher all-cause mortality risks than nonsmokers. Relative to nonsmokers, current smokers of more than 40 pack-years ([OR],1.85; 95% CI,1.33–2.56) had a higher all-cause mortality risk. Compared to nonsmokers, current smokers who started smoking before age 20 ([OR],1.91; 95% CI,1.43–2.54) had a higher all-cause mortality risk, and former smokers in the lower pack-year group who quit after age 41 (median) ([OR],3.19; 95% CI,1.83–5.56) also had a higher risk of death after adjustment. Furthermore, former smokers who were also former drinkers had the highest significant risk of mortality than never smokers or drinkers. ( P for interaction = 0.034). Conclusions This study provides evidence that current smokers and former smokers have a higher mortality risk than nonsmokers and would benefit from cessation at a younger age.

The inerter is a vibration control element related to the acceleration between its two ends, which can increase inertia through a speed-increasing mechanism. Applying the inerter to a vibration isolator can enhance its low-frequency vibration isolation performance. Frictional force always exists in the high-speed mechanism of the inerter. Even if it is not large, its influence on the dynamic performance of the low-speed end cannot be ignored. This study analyzes the force of a ball-screw inerter using the kinetic energy theorem. The inerter force is then expanded into the first-order Taylor approximation, from which the inerter coefficient and apparent friction coefficient are determined. Based on the approximate formula of the inerter force, the nonlinear dynamic model and its corresponding dynamic equation for the inerter vibration isolator under base excitation are established. The nonlinear dynamic equation is then solved by averaging method, and the approximate analytical solutions for the relative displacement, absolute displacement, and displacement transmissibility are obtained. The analysis results show that a larger apparent friction coefficient reduces the resonance peaks of the displacement transmissibility and relative displacement amplitude, but it slightly increases the initial vibration isolation frequency, as well as the resonance and valley frequencies of the displacement transmissibility and relative displacement. Increasing the inerter-mass ratio can reduce the resonance frequency and initial vibration isolation frequency, thereby broadening the vibration isolation frequency domain. When friction is considered, increasing the inerter-mass ratio can suppress the resonance peaks of the displacement transmissibility and relative displacement.

An array of generative adversarial networks (GANs) have been accomplishing the realistic generation of full 3D brain images. This largely follows a common procedure of sampling from a latent space prior Z (i.e., random vectors) and mapping it to realistic images in X (e.g., 3D brains), but a naıve implementation also comes with the ubiquitous mode collapse issue. This challenge has recently been addressed by strongly imposing certain characteristics, such as Gaussianness, to the prior by also explicitly mapping X to Z via encoder. This Auto- Encoder type GANs, however, fail to accurately map 3D brain images to the desirable prior, which the generator assumes to be sampling the random vectors from. While Variational Auto-Encoding GAN (VAE-GAN) handles this mode collapse issue by explicitly imposing Gaussianness, this also causes blurriness in images. In this thesis, we demonstrate how our cycle consistent embedding GAN (CCE-GAN) is able to solve both the mode collapse and blurriness issues by accurately encoding 3D MRIs to the standard normal prior while maintaining the image generation quality. Using our trained novel model with T1 MRI brain images from Alzheimer’s Disease Neuroimaging Initiative (ADNI) and FLAIR tumor MRI brain images from Brain Tumor Segmentation (BraTS) datasets, we will show how an improved prior Z space can lead to an output distribution free of mode collapse and of high image quality. We also quantitatively and qualitatively assess the embeddings to reaffirm the importance of embedding in GAN for 3D brain generation.

Dear Editor,The 2002–2003 global pandemic caused by severe acute respiratory syndrome coronavirus（SARS-CoV）infected around 8,000 people with 10%mortality（http：//www.who.int/csr/sars/en/）.

The emergence of SARS-CoV-2 variants and potentially other highly pathogenic sarbecoviruses in the future highlights the need for pan-sarbecovirus vaccines. Here, we discovered a new STING agonist, CF501, and found that CF501-adjuvanted RBD-Fc vaccine (CF501/RBD-Fc) elicited significantly stronger neutralizing antibody (nAb) and T cell responses than Alum- and cGAMP-adjuvanted RBD-Fc in mice. Vaccination of rabbits and rhesus macaques (nonhuman primates, NHPs) with CF501/RBD-Fc elicited exceptionally potent nAb responses against SARS-CoV-2 and its nine variants and 41 S-mutants, SARS-CoV and bat SARSr-CoVs. CF501/RBD-Fc-immunized hACE2-transgenic mice were almost completely protected against SARS-CoV-2 challenge, even 6 months after the initial immunization. NHPs immunized with a single dose of CF501/RBD-Fc produced high titers of nAbs. The immunized macaques also exhibited durable humoral and cellular immune responses and showed remarkably reduced viral load in the upper and lower airways upon SARS-CoV-2 challenge even at 108 days post the final immunization. Thus, CF501/RBD-Fc can be further developed as a novel pan-sarbecovirus vaccine to combat current and future outbreaks of sarbecovirus diseases.