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In this paper, a novel radial spatial power combiner based on the WRD650 standard double‐ridge waveguide has been proposed. The combiner exhibits a significant increase in operating bandwidth due to the utilization of the upper ridge taper and the lower ridge extension. The principle prototype is designed, processed, and tested. The test results show that the overall return loss of the dual‐ridge waveguide power combiner is better than −10 dB at the input port, and the insertion loss at each output port is better than −2 dB in the 6–18 GHz band, and the maximum phase difference at each port does not exceed 11°. Due to the limitations of the processing accuracy, the final overall synthesis efficiency is higher than 70%. [ABSTRACT FROM AUTHOR]

Due to the excellent characteristics of Synthetic Aperture Radar (SAR), it has become an important technical means for land and sea target detection applications worldwide. However, the SAR image imaging process is often accompanied by speckle noise, which affects the accuracy of target detection. For this problem, this paper proposes an SAR image reconstruction model based on image denoising and feature extraction. Given a noisy SAR image, at each pixel of the image, the value of the singularity index of a metric defined by the signal gradient norm density is calculated. Then through a hierarchical decomposition of these singular indices, a set of pixels containing the most informative feature set of the image is extracted, and a denoised image is reconstructed using the extracted features. In comparison to traditional filtering and denoising techniques such as non-local filtering, this algorithm achieves remarkable local filtering and denoising effects while preserving the image's texture information. The denoising performance of the proposed method is evaluated through a series of quantitative indicators and visual comparisons. The results demonstrate that this method effectively reduces background clutter, resulting in a higher contrast between the target and the background. [ABSTRACT FROM AUTHOR]

Accumulating evidence shows that the abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) can significantly affect the long-term prognosis of coronary artery bypass grafting. This study aimed to explore the factors affecting the proliferation, migration, and phenotypic transformation of VSMCs. First, we stimulated VSMCs with different platelet-derived growth factor-BB (PDGF-BB) concentrations, analyzed the expression of phenotype-associated proteins by Western blotting, and examined cell proliferation by scratch wound healing and the 5-ethynyl-2-deoxyuridine (EdU) assay. VSMC proliferation was induced most by PDGF-BB treatment at 20 ng/mL. miR-200a-3p decreased significantly in A7r5 cells stimulated with PDGF-BB. The overexpression of miR-200a-3p reversed the downregulation of α-SMA (p < 0.001) and the upregulation of vimentin (p < 0.001) caused by PDGF-BB. CCK8 and EdU analyses showed that miR-200a-3p overexpression could inhibit PDGF-BB-induced cell proliferation (p < 0.001). However, flow cytometric analysis showed that it did not significantly increase cell apoptosis. Collectively, the overexpression of miR-200a-3p inhibited the proliferation and migration of VSMCs induced by PDGF-BB, partly by affecting phenotypic transformation-related proteins, providing a new strategy for relieving the restenosis of vein grafts. [ABSTRACT FROM AUTHOR]

BACKGROUND: Lactic acid bacteria (LABs) are widely present in foods and affect the flavour of fermented cultures. This study investigates the effects of fermentation with Lactobacillus acidophilus JYLA-16 (La), Lactobacillus plantarum JYLP-375 (Lp), and Lactobacillus rhamnosus JYLR-005 (Lr) on the flavour profile of blueberry juice. RESULTS: This study showed that all LABs strains preferentially used glucose rather than fructose as the carbon source during fermentation. Lactic acid was the main fermentation product, reaching 7.76 g L-1 in La-fermented blueberry juice, 5.86 g L-1 in Lp-fermented blueberry juice, and 6.41 g L-1 in Lr-fermented blueberry juice. These strains extensively metabolized quinic acid, whereas oxalic acid metabolism was almost unaffected. Sixty-four volatile compounds were identified using gas chromatography--ion mobility spectrometry (GC--IMS). All fermented blueberry juices exhibited decreased aldehyde levels. Furthermore, fermentation with La was dominated by alcohols, Lp was dominated by esters, and Lr was dominated by ketones. Linear discriminant analysis of the electronic nose and principal component analysis of the GC--IMS data effectively differentiated between unfermented and fermented blueberry juices. CONCLUSION: This study informs LABs selection for producing desirable flavours in fermented blueberry juice and provides a theoretical framework for flavour detection. [ABSTRACT FROM AUTHOR]

Cancer is one of the most common and deadliest diseases affecting millions of human beings globally. Treatment of cancer has achieved great advancements, and chemotherapy remains one of the most important means. However, the chemotherapy suffers from apparent limitations including drug resistance, systemic toxicity, adverse effects, and tumor recurrence, creating an urgent demand to develop novel anticancer chemotherapeutics. Furoxan derivatives could exert anticancer activity via releasing high concentrations of nitric oxide (NO), which could induce cellular apoptosis, arrest cell cycle, inhibit the migration and invasion of cells, and suppress angiogenesis. Hence, furoxan derivatives demonstrated potent in vitro and in vivo anticancer efficiency. In particular, furoxan hybrids, combination of other anticancer pharmacophores with furoxan moiety, demonstrated significant therapeutic effects on various cancers including drug-resistant forms since these derivatives could act on multiple targets in cancer cells simultaneously. Accordingly, furoxan hybrids constitute an important source in the development of novel chemotherapeutic agents with anticancer activity. This review is to highlight the current scenario of furoxan hybrids with anticancer potential, covering articles published from 2012 to present. The structure--activity relationships and mechanisms of action are discussed to continuously open up a map for the remarkable exploration of more effective candidates. [ABSTRACT FROM AUTHOR]

An in-house designed transmission X-ray microscopy (TXM) instrument has been developed and commissioned at beamline BL18B of the Shanghai Synchrotron Radiation Facility (SSRF). BL18B is a hard (5-14 keV) X-ray bending-magnet beamline recently built with sub-20 nm spatial resolution in TXM. There are two kinds of resolution mode: one based on using a highresolution-based scintillator-lens-coupled camera, and the other on using a medium-resolution-based X-ray sCMOS camera. Here, a demonstration of full-field hard X-ray nano-tomography for high-Z material samples (e.g. Au particles, battery particles) and low-Z material samples (e.g. SiO2 powders) is presented for both resolution modes. Sub-50 nm to 100 nm resolution in three dimensions (3D) has been achieved. These results represent the ability of 3D non-destructive characterization with nano-scale spatial resolution for scientific applications in many research fields. [ABSTRACT FROM AUTHOR]

We demonstrated a practical and general methodology for the synthesis of secondary trifluoromethyl boronic esters through visible light induced decarboxylative alkylation reaction. This reaction was driven by the photochemical activity of electron donor-acceptor (EDA) complex. Except for wide group tolerance, moderate to high yields and simple reaction conditions, the practicality of this protocol was further demonstrated by direct modification of bioactive molecules and further derivations. [ABSTRACT FROM AUTHOR]

Background: There is no consensus on the optimal regimen for unresectable recurrent hepatocellular carcinoma (HCC), so this retrospective study aimed to evaluate the efficacy and safety of transarterial chemoembolization (TACE) combined with lenvatinib and PD-1 inhibitors (T-L-P) versus TACE combined with lenvatinib (T-L) or TACE alone. Method: Data were collected from 204 patients with unresectable recurrent HCC who received T-L-P, T-L, or TACE alone at three medical centers from January, 2019 to December, 2020 for analysis. The survival outcomes, tumor response, and adverse events were compared between three groups, and risk factors were further investigated. Results: The median overall survival in the T-L-P, T-L, and TACE alone groups were not reached, 25.6, and 15.7 months, respectively (p < 0.001). The median progression-free survival in the T-L-P, T-L, and TACE alone groups were 24.1, 17.3, and 13.7 months, respectively (p < 0.001). The best objective response rate in the T-L-P, T-L, and TACE alone groups were 70.4%, 48.9%, and 42.5%, respectively. The best disease control rate in the T-L-P, T-L, and TACE alone groups were 100.0%, 97.8%, and 87.5%, respectively. There was no significant difference between the T-L-P and T-L groups for Grade 3/4 adverse events. Conclusion: T-L-P regimen was safe and superior to T-L or TACE alone in improving survival for unresectable recurrent HCC patients. [ABSTRACT FROM AUTHOR]

Background and Objective: Although cementum plays an essential role in tooth attachment and adaptation to occlusal force, the regulatory mechanisms of cementogenesis remain largely unknown. We have previously reported that Axin2-expressing (Axin2+) mesenchymal cells in periodontal ligament (PDL) are the main cell source for cementum growth, and constitutive activation of Wnt/β-catenin signaling in Axin2+ cells results in hypercementosis. Therefore, the aim of the present study was to further evaluate the effects of β-catenin deletion in Axin2+ cells on cementogenesis. Materials and Methods: We generated triple transgenic mice to conditionally delete β-catenin in Axin2-lineage cells by crossing Axin2CreERT2/+; R26RtdTomato/+ mice with β-cateninflox/ flox mice. Multiple approaches, including X-ray analysis, micro-CT, histological stainings, and immunostaining assays, were used to analyze cementum phenotypes and molecular mechanisms. Results: Our data revealed that loss of β-catenin in Axin2+ cells led to a cementum hypoplasia phenotype characterized by a sharp reduction in the formation of both acellular and cellular cementum. Mechanistically, we found that conditional removal of β-catenin in Axin2+ cells severely impaired the secretion of cementum matrix proteins, for example, bone sialoprotein (BSP), dentin matrix protein 1 (DMP1) and osteopontin (OPN), and markedly inhibited the differentiation of Axin2+ mesenchymal cells into osterix+ cementoblasts. Conclusions: Our findings confirm the vital role of Axin2+ mesenchymal PDL cells in cementum growth and demonstrate that Wnt/β-catenin signaling shows a positive correlation with cementogenic differentiation of Axin2+ cells. [ABSTRACT FROM AUTHOR]

The number of layers of 2D materials is of great significance for regulating the performance of nanoelectronic devices and optoelectronic devices, where the optimal thickness of the target sample should be determined before further physical research or device manufacturing steps. At present, a variety of different optical technologies have been proposed to determine the thickness of samples by using the relationship between the number of layers and optical properties, including optical contrast, optical imaging, Raman spectra, photoluminescence spectra, nonlinear spectra, near-field optical imaging, ellipsometry spectra, and hyperspectral imaging. In the past decade, the rapidly growing number of 2D materials and their heterostructures has exceeded the capacity of traditional experimental and computational methods. In recent years, machine learning (ML) is emerging as a powerful tool to support such traditional methods, which brings new opportunities to tap the potential of optical technology in a more perspicacious way. The application of optical technology has greatly facilitated the acquisition of optical information of materials, while ML algorithms provide a fast, high-throughput, and intelligent way to complete back-end data processing and inference. A profound integration of conventional optical technologies and ML algorithms significantly helps 2D materials progress in basic studies and practical applications and further promotes industrial manufacturing. [ABSTRACT FROM AUTHOR]

There is an increasing demand for simple and efficient sample delivery technology to match the rapid development of serial crystallography and its wide application in analyzing the structural dynamics of biological macromolecules. Here, a microfluidic rotating-target device is presented, capable of three-degrees-of-freedom motion, including two rotational degrees of freedom and one translational degree of freedom, for sample delivery. Lysozyme crystals were used as a test model with this device to collect serial synchrotron crystallography data and the device was found to be convenient and useful. This device enables in situ diffraction from crystals in a microfluidic channel without the need for crystal harvesting. The circular motion ensures that the delivery speed can be adjusted over a wide range, showing its good compatibility with different light sources. Moreover, the three-degrees-of-freedom motion guarantees the full utilization of crystals. Hence, sample consumption is greatly reduced, and only 0.1 mg of protein is consumed in collecting a complete dataset. [ABSTRACT FROM AUTHOR]

In order to study the effect of fuel Mg and metal oxide CuO on the reaction of thermite, different proportions of Al‐Mg alloys and MoO3‐CuO metal oxides were prepared by mechanical ball milling, and then the samples of Al1‐xMgx/(MoO3)1‐xCuOx composite thermite were prepared by ultrasonic dispersion method. The samples were characterized by SEM, TG‐DSC, and constant pressure combustion experiments. The results show that in quaternary thermite, adding CuO increases initial exothermic temperature, but increases exothermic heat in high‐temperature regions, and effectively reduces the activation energy of the thermite reaction. On the contrary, adding Mg reduces exothermic heat in the high‐temperature areas, but reduces initial exothermic temperature. After calculation, the quaternary thermite with the best exothermic performance is Al0.8Mg0.2/(MoO3)0.5CuO0.5. Its initial reaction temperature is only 614 °C, but the heat release is up to 2217 J/g. Its activation energy is only 106.7 kJ/mol, but the critical temperature of thermal explosion is up to 927.9 K. At the same time, Al0.8Mg0.2/(MoO3)0.5CuO0.5 has better combustion performance. During combustion, the flame is jet‐like, and the main products are Al2O3, Mo and Cu. This work provides a reference for studying the thermal safety and combustion performance of quaternary thermite. [ABSTRACT FROM AUTHOR]

BACKGROUND: The oriental fruit fly, Bactrocera dorsalis (Hendel) is a worldwide pest damaging a wide range of hosts. Due to the long-term indiscriminate use of insecticides, B. dorsalis has developed serious resistance to several insecticides. UDP-glycosyltransferases (UGTs) are secondary metabolic enzymes involved in biotransformation and play an important role in the metabolism of plant secondary metabolites and synthetic insecticides in insects. Thus, we suspect that UGTs in B. dorsalis play an important role in insecticide tolerance. RESULTS: In this study, 31 UGT genes were identified in the genome of B. dorsalis, belonging to 13 subfamilies. Real-time quantitative polymerase chain reaction (RT-qPCR) results revealed that 12 UGT genes were highly expressed in the antennae, midgut, Malpighian tubule and fat body. The mRNA expressions of 17 UGT genes were up-regulated upon exposure to λ-cyhalothrin, imidacloprid, abamectin and chlorpyrifos. Knockdown of the selected five UGT genes (BdUGT301D2, BdUGT35F2, BdUGT36K2, BdUGT49D2, BdUGT50B5) by RNA interference increased the mortality of B. dorsalis from 9.29% to 27.22% upon exposure to four insecticides. CONCLUSION: The abundance of UGTs in B. dorsalis is similar to other insect species, and 12 out of 31 UGTs were specifically expressed in metabolic tissues, suggesting a key role in detoxification. Down-regulation of five selected UGT genes increased the susceptibility of B. dorsalis to various insecticides, indicating that UGTs may play an important role in tolerance of B. dorsalis to multiple insecticides. [ABSTRACT FROM AUTHOR]

Rhododendron henanense subsp. lingbaoense (hereafter referred to as R. henanense) is an endemic species naturally distributed in the Henan province, China, with high horticultural, ornamental and medicinal value. Herein, we report a de novo genome assembly for R. henanense using a combination of PacBio long read and Illumina short read sequencing technologies. In total, we assembled 634.07 Mb with a contig N50 of 2.5 Mb, representing ~96.93% of the estimated genome size. By applying Hi‐C data, 13 pseudochromosomes of R. henanense genome were assembled, covering ~98.21% of the genome assembly. The genome was composed of ~65.76% repetitive sequences and 31,098 protein‐coding genes, 88.77% of which could be functionally annotated. Rhododendron henanense displayed a high level of synteny with other Rhododendron species from the Hymenanthes subgenus. Our data also suggests that R. henanense genes related to stress responses have undergone expansion, which may underly the unique abiotic and biotic stress resistance of the species. This alpine Rhododendron chromosome‐scale genome assembly provides fundamental molecular resources for germplasm conservation, breeding efforts, evolutionary studies, and elucidating the unique biological characteristics of R. henanense. [ABSTRACT FROM AUTHOR]

Introduction: The coronavirus disease 2019 (COVID-19) has quickly become a global threat to public health, and it is difficult to predict severe patients and their prognosis. Here, we intended developing effective models for the late identification of patients at disease progression and outcome. Methods: A total of 197 patients were included with a 20-day median follow-up time. We first developed a nomogram for disease severity discrimination, then created a prognostic nomogram for severe patients. Results: In total, 40.6% of patients were severe and 59.4% were non-severe. The multivariate logistic analysis indicated that IgG, neutrophil-to-lymphocyte ratio (NLR), lactate dehydrogenase, platelet, albumin, and blood urea nitrogen were significant factors associated with the severity of COVID-19. Using immune response phenotyping based on NLR and IgG level, the logistic model showed patients with the NLRhiIgGhi phenotype are most likely to have severe disease, especially compared to those with the NLRloIgGlo phenotype. The C-indices of the two discriminative nomograms were 0.86 and 0.87, respectively, which indicated sufficient discriminative power. As for predicting clinical outcomes for severe patients, IgG, NLR, age, lactate dehydrogenase, platelet, monocytes, and procalcitonin were significant predictors. The prognosis of severe patients with the NLRhiIgGhi phenotype was significantly worse than the NLRloIgGhi group. The two prognostic nomograms also showed good performance in estimating the risk of progression. Conclusions: The present nomogram models are useful to identify COVID-19 patients with disease progression based on individual characteristics and immune response-related indicators. Patients at high risk for severe illness and poor outcomes from COVID-19 should be managed with intensive supportive care and appropriate therapeutic strategies. [ABSTRACT FROM AUTHOR]

Purpose: As a subgroup of lung cancer, small cell lung cancer (SCLC) is characterized by a short tumor doubling time, high rates of early occurred distant cancer spread, and poor outcomes. Despite its exquisite sensitivity to chemotherapy and radiotherapy, acquired drug resistance and tumor progression are typical. This study aimed to develop a robust signature based on immune-related genes to predict the outcome of patients with SCLC. Methods: The expression data of 77 SCLC patients from George's cohort were divided into training set and testing set, and 1534 immune-related genes from ImmPort database were used to generate and validate the signature. Cox proportional hazards and the Kaplan-Meier analysis were used for developing and testing the prognostic signature. Single-sample gene set enrichment analysis was used to determine immune cell infiltration phenotypes. Results: A 10-gene model comprising NR3C1, NR1D2, TANK, ARAF, HDGF, INHBE, LRSAM1, PLXNA1, PML, and SP1 with the highest frequency after 1000 interactions, was chosen to construct immune-related signature. This signature showed robust predictive value for SCLC patients' survival in both training and testing sets. This signature was weakly associated with the clinic pathological values like TNM stage. Furthermore, patients with low risk presented with activation of immune signal pathways, and specific immune cell infiltration with high levels of CD56bright NK cells but low levels of CD8+ T cells, mast cells, and helper T cells. Conclusion: The present study developed immune-related signature that may help predict the prognosis of SCLC patients, which reflects an unappreciated level of heterogeneity of immunophenotype associated with diverse prognosis for specific subsets in this highly lethal cancer type. [ABSTRACT FROM AUTHOR]

Aim: Disentangling the drivers of community assembly and species diversity in space and time is critical to elucidating metacommunity theory. However, our understanding of how metacommunity structuring will change over time remains insufficient, especially in rivers in the monsoon climate zone. We examined whether (1) the idealized metacommunity structure is different among seasons and (2) the relative importance of underlying mechanisms on community assembly varies within and across tributaries as well as among seasons. Location: Five tributaries in the Hanjiang River Basin. Taxon: Macroinvertebrates. Methods: Benthic macroinvertebrates and environmental data were collected seasonally (i.e. spring, summer, autumn and winter) from the same 70 sampling sites. The elements of metacommunity structure (EMS) framework was employed to identify which idealized topology best characterizes the actual metacommunity. Redundancy analysis and variance partitioning procedures were applied to determine key environmental and spatial factors and to examine their relative contributions to variation in community structure in different seasons. Results: The best-fit metacommunity typologies were consistent over time, with metacommunity structure in each season displaying Clementsian gradients, characterized by high degrees of coherence and turnover, and positive boundary clumping. Environmental control prevailed over spatial processes in structuring macroinvertebrate communities, but their relative influence on community variation was context-dependent. Particularly, environmental filtering was the predominant mechanism at the intermediate spatial scale. However, spatial processes had gradually stronger effects at smaller and larger extents. Main conclusions: Both EMS analysis and the variance partitioning approach suggested environmental filtering was the principal structuring processes for macroinvertebrate assemblages throughout the year, although mass effects and dispersal limitation also played significant roles at smaller and larger spatial extents respectively. Considering that the most influential environmental factors shaping macroinvertebrate communities were variable across seasons, we argue that spatio-temporal investigations would provide more information on community assembly than single snapshot studies. [ABSTRACT FROM AUTHOR]

Circular RNA is a newly discovered member of non-coding RNA (ncRNA) and regulates the target gene by acting as a micro-RNA sponge. It plays vital roles in various diseases. However, the functions of circular RNA in non-small cell lung cancer (NSCLC) remain still unclear. Our data showed that circ-WHSC1 was highly expressed in NSCLC cells and tissues. Both in vitro and in vivo experiments showed that circ-WHSC1 promoted NSCLC proliferation. circ-WHSC1 also promoted the migration and invasion of lung cancer cells. Through bioinformatic analysis and functional experiments, we showed that circ-WHSC1 could act as a sponge for micro-RNA-7 (miR-7) and regulate the expression of TAB2 (TGF-beta activated kinase one binding protein two). Inhibition of the circ-WHSC1/miR-7/TAB2 pathway could effectively attenuate lung cancer progression. In summary, this study confirmed the existence and oncogenic function of circ-WHSC1 in NSCLC. The research suggests that the circ-WHSC1/miR-7/TAB2 axis might be a potential target for NSCLC therapy. [ABSTRACT FROM AUTHOR]

An efficient iodine-catalyzed [3+3+1] annulation for the construction of dihydrooxepine scaffolds with quinoline units was developed. This strategy involves a seven-membered dihydrooxepine with a broad substrate scope through a formal three-component tandem reaction. Further derivation of the target product produced a trioxabicycle scaffold, which formed the basic core of natural products and pharmaceutical molecules. [ABSTRACT FROM AUTHOR]

Nintedanib, an Food and Drug Administration (FDA) approved multiple tyrosine kinase inhibitor, exhibits an anti-fibrotic effect in lung and kidneys. Its effect on peritoneal fibrosis remains unexplored. In this study, we found that nintedanib administration lessened chlorhexidine gluconate (CG)-induced peritoneal fibrosis and reduced collagen I and fibronectin expression. This coincided with suppressed phosphorylation of platelet-derived growth factor receptor, fibroblast growth factor receptors, vascular endothelial growth factor receptor and Src family kinase. Mechanistically, nintedanib inhibited injury-induced mesothelial-to-mesenchymal transition (MMT), as demonstrated by decreased expression of a-smooth muscle antigen and vimentin and preserved expression of E-cadherin in the CG-injured peritoneum and cultured human peritoneal mesothelial cells exposed to transforming growth factor-ß1. Nintedanib also suppressed expression of Snail and Twist, two transcription factors associated with MMT in vivo and in vitro. Moreover, nintedanib treatment inhibited expression of several cytokines/chemokines, including tumour necrosis factor-a, interleukin-1ß and interleukin-6, monocyte chemoattractant protein-1 and prevented infiltration of macrophages to the injured peritoneum. Finally, nintedanib reduced CG-induced peritoneal vascularization. These data suggest that nintedanib may attenuate peritoneal fibrosis by inhibiting MMT, inflammation, and angiogenesis and have therapeutic potential for the prevention and treatment of peritoneal fibrosis in patients on peritoneal dialysis. [ABSTRACT FROM AUTHOR]

Water turbidity is an important indicator of water quality, which regulates primary production by changing the light field in the water column. Thus, monitoring the spatial and temporal variations in water turbidity is environmentally and biologically important. In this study, nine commonly used spectral index algorithms were tuned using in situ data collected from two field surveys in the Pearl River Estuary of China, and the spectral ratios between the red and green bands (i.e., Rrs(678)/Rrs (531) and Rrs (645)/Rrs(555) were selected as the optimal indicator to estimate water turbidity in this region. A long-term environmental data record of water turbidity was established for the Pearl River Estuary by applying the proposed algorithm to MODIS/Aqua data covering the estuary from 2003 to 2019. Water turbidity in the Pearl River Estuary has significantly decreased at a rate of 0.11 nephelometric turbidity units (NTU) per year (R² = 0.84, p < 0.01). The decline in water turbidity is linked with sea-level rise in this area. Sea-level rise may cause the longitudinal and lateral landward retreat of estuarine turbidity maxima (ETMs), directly contributing to the decline in water turbidity. Further, the sea-level rise and the decline in water turbidity in the Pearl River Estuary are also two effects resulting from similar processes, such as urbanization. A high degree of correlation was observed between the water turbidity and salinity, which could facilitate promising monitoring of the increasingly severe saltwater intrusions in this region. [ABSTRACT FROM AUTHOR]

The positive development of migrant children in China is hampered due to their unequal accessibility to quality urban education resources. This research aimed at exploring the developmental trajectories of migrant and urban children's literacy and mathematics performance, as well as the impact of family socioeconomic status (SES) and parenting styles, including the mediating effect of parenting styles, by comparing migrant children with their urban counterparts. Growth mixture modeling identified distinguishable trajectories of mathematics development for migrant children (i.e., "falling behind" and "keeping pace" groups) and urban children (i.e., "catching up" and "keeping pace" groups), as well as distinguishable trajectories of literacy development for migrant children (i.e., "jumpstarting" and "keeping pace" groups) and urban children ("falling behind" and "steadily progressing" groups). Multinomial logistic regression analyses further clarified that authoritative parenting increased the likelihood of favorable trajectories of migrant children's mathematics development and urban children's literacy and mathematics development. Family SES enhanced migrant children's mathematics development. Family SES contributed to urban children's literacy development through authoritative parenting, yet such a mediating effect was not observed for migrant children. This study highlights the importance of focusing on distinct trajectories of migrant and urban children's literacy and mathematics in improving their school achievement. [ABSTRACT FROM AUTHOR]

The soil nitrogen (N) and phosphorus (P) availability often constrains soil carbon (C) pool, and elevated N deposition could further intensify soil P limitation, which may affect soil C cycling in these N-rich and P-poor ecosystems. Soil microbial residues may not only affect soil organic carbon (SOC) pool but also impact SOC stability through soil aggregation. However, how soil nutrient availability and aggregate fractions affect microbial residues and the microbial residue contribution to SOC is still not well understood. We took advantage of a 10-year field fertilization experiment to investigate the effects of nutrient additions, soil aggregate fractions, and their interactions on the concentrations of soil microbial residues and their contribution to SOC accumulation in a tropical coastal forest. We found that continuous P addition greatly decreased the concentrations of microbial residues and their contribution to SOC, whereas N addition had no significant effect. The P-stimulated decreases in microbial residues and their contribution to SOC were presumably due to enhanced recycling of microbial residues via increased activity of residue-decomposing enzymes. The interactive effects between soil aggregate fraction and nutrient addition were not significant, suggesting a weak role of physical protection by soil aggregates in mediating microbial responses to altered soil nutrient availability. Our data suggest that the mechanisms driving microbial residue responses to increased N and P availability might be different, and the P-induced decrease in the contribution of microbial residues might be unfavorable for the stability of SOC in N-rich and P-poor tropical forests. Such information is critical for understanding the role of tropical forests in the global carbon cycle. [ABSTRACT FROM AUTHOR]

A straightforward and convenient route has been developed for the synthesis of 3-unsubstituted phthalide derivatives from aryl amides and paraformaldehyde by ruthenium(II)-catalyzed C–H activation. The reaction proceeds through tandem ortho-hydroxymethylation of aryl amide and subsequent intramolecular lactonization. [ABSTRACT FROM AUTHOR]

Target echoes are inevitably contaminated by the direct‐path signal, multipath signal and possible interference in passive bistatic radar (PBR). Cancellation performance is deteriorated as the interference signal is irrelevant to the transmitted signal and the target echoes are submerged by in the sidelobe of the spread clutter echoes. In this study, the cancellation problem is addressed, involving clutter and interference. In this method, the spread clutter echoes are cancelled by constructing a tailored clutter subspace. Besides, the interference is also cancelled by constructing a tailored interference subspace. The sample of the interference signal is obtained from the beam channel after clutter cancellation. The performance of the proposed method is first verified by the simulation result. Then its effectiveness is also demonstrated with the application of the real data collected from an experimental PBR system. [ABSTRACT FROM AUTHOR]

SiC MOSFETs (silicon carbide metal-oxide semiconductor field-effect transistors) are replacing Si insulated gate bipolar transistors in many power conversion applications due to their superior performance. However, ruggedness and reliability of SiC MOSFETs are still big concern for their widespread applications in the market, especially in safety-critical applications. The objective of this study is to provide a comprehensive picture on the ruggedness and reliability of commercial SiC MOSFETs, discover their failure or degradation mechanism, and propose some possible mitigation methods through both literature survey and in-depth analysis. The ruggedness of SiC MOSFETs discussed here includes short-circuit (SC) ruggedness, avalanche ruggedness, and their failure mechanism. The reliability issues include gate oxide reliability, degradation under high-temperature bias stress, repetitive SC stress, avalanche stress, power cycling stress, body diode's surge current stress, and their degradation mechanism. Furthermore, this study discusses methods and solutions to improve their ruggedness and reliability. [ABSTRACT FROM AUTHOR]

Precipitation is projected to change intensity and seasonal regime under current global projections. However, little is known about how seasonal precipitation changes will affect soil respiration, especially in seasonally dry tropical forests. In a seasonally dry tropical forest in South China, we conducted a precipitation manipulation experiment to simulate a delayed wet season (DW) and a wetter wet season (WW) over a three‐year period. In DW, we reduced 60% throughfall in April and May to delay the onset of the wet season and irrigated the same amount water into the plots in October and November to extend the end of the wet season. In WW, we irrigated 25% annual precipitation into plots in July and August. A control treatment (CT) receiving ambient precipitation was also established. Compared with CT, DW significantly increased soil moisture by 54% during October to November, and by 30% during December to April. The treatment of WW did not significantly affect monthly measured soil moisture. In 2015, DW significantly increased leaf area index and soil microbial biomass but decreased fine root biomass. In contrast, WW significantly decreased fine root biomass and forest floor litter stocks. Soil respiration was not affected by DW, which could be attributed to the increased microbial biomass offsetting the decrease in fine root biomass. In contrast, WW significantly increased soil respiration from 3.40 to 3.90 μmol m−2 s−1 in the third year, mainly due to the increased litter decomposition and soil pH (from 4.48 to 4.68). The present study suggests that both a delayed wet season and a wetter wet season will have significant impacts on soil respiration‐associated ecosystem components. However, the ecosystem components can respond in different directions to the same change in precipitation, which ultimately affected soil respiration. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to reveal the correlation between superior mesenteric artery (SMA) blood flow in the first 12 hours of life and the risk of necrotizing enterocolitis (NEC) in preterm neonates. Methods: We conducted a prospective study. There were 104 preterm neonates included in our study. The SMA blood flow of each neonate was measured during the first 12 hours of life if the hemodynamic situation was stable. The results of Doppler ultrasound were confidential to the neonatologists and nurses. All of the demographics, comorbidities, and outcomes were recorded and analyzed. Results: Among all of the demographics and comorbidities, the gestational age was related to the measurements of SMA blood flow. We conducted a single‐factor analysis of the occurrence of NEC, including the peak systolic velocity (PSV), end‐diastolic velocity, time‐averaged mean velocity, differential velocity (DV), resistive index, and pulsatility index. A higher PSV (median [interquartile range], 54.165 [42.423–68.463] versus 42.195 [34.278–48.553] cm/s; P =.027) and DV (median [interquartile range], 47.445 [35.010–60.043] versus 32.565 [27.545–39.073] cm/s; P =.020) were significantly related to the risk of NEC. In the logistic analysis including gestational age, PSV, and DV, NEC was significantly associated with gestational age (odds ratio [95% confidence interval], 0.644 [0.456–0.908]; P =.012) and DV (odds ratio [95% confidence interval], 1.144 [1.058–1.237]; P < .01). The area under the receiver operating characteristic curve for the DV was 0.768, with sensitivity 0.875 and specificity 0.604. The cutoff value of the DV was 34.835 cm/s. Conclusions: From this single‐center study, we can see the promising value of Doppler ultrasound for the prediction of NEC, but further research is needed. [ABSTRACT FROM AUTHOR]

Interfacial phase-change memory (iPCM) based on layer-structured Ge-Sb-Te crystals has been recently proposed, offering an energy-efficient implementation of nonvolatile memory cells and supplementing the development of Ge-Sb-Tebased phase-change random access memories (PRAMs). Although the working principle of iPCM is still under debate, it is believed that layer-switching plays a role in the switching process between the low-resistance and high-resistance states of iPCM memory cells. However, the role of Ge in forming swapped bilayers—the key elements for layer-switching—is not yet clarified. This work manages to achieve layer-switching in Sb2Te3 thin films by manipulating the formation of bilayer defects using magnetron sputtering and post-thermal annealing. By combining scanning transmission electron microscopy (STEM) experiments with density functional theory (DFT) calculations, the essential role of Sb-Te intermixing is elucidated in stabilizing swapped bilayers at a low energy cost. In situ STEM experiments provide a real-time and real-space view of dynamical reconfiguration of van der Waals-like gaps in Sb2Te3 thin films under electron-beam irradiation. The results show that the Ge atoms are not necessary for the formation and motion of swapped bilayers, providing atomic insights on the layer-switching mechanism in layer-structured binary and ternary group V- and IV–V-tellurides for memory applications. [ABSTRACT FROM AUTHOR]

Interfacial phase-change memory (iPCM) based on layer-structured Ge-Sb-Te crystals has been recently proposed, offering an energy-efficient implementation of nonvolatile memory cells and supplementing the development of Ge-Sb-Tebased phase-change random access memories (PRAMs). Although the working principle of iPCM is still under debate, it is believed that layer-switching plays a role in the switching process between the low-resistance and high-resistance states of iPCM memory cells. However, the role of Ge in forming swapped bilayers—the key elements for layer-switching—is not yet clarified. This work manages to achieve layer-switching in Sb2Te3 thin films by manipulating the formation of bilayer defects using magnetron sputtering and post-thermal annealing. By combining scanning transmission electron microscopy (STEM) experiments with density functional theory (DFT) calculations, the essential role of Sb-Te intermixing is elucidated in stabilizing swapped bilayers at a low energy cost. In situ STEM experiments provide a real-time and real-space view of dynamical reconfiguration of van der Waals-like gaps in Sb2Te3 thin films under electron-beam irradiation. The results show that the Ge atoms are not necessary for the formation and motion of swapped bilayers, providing atomic insights on the layer-switching mechanism in layer-structured binary and ternary group V- and IV–V-tellurides for memory applications. [ABSTRACT FROM AUTHOR]

We examine corporate security choice by simulating an economy populated by adaptive agents who learn about the structure of security returns and prices through experience. Through a process of evolutionary selection, each agent gravitates toward strategies that generate the highest payoffs. Despite the fact that markets are perfect and agents maximize value, a financing hierarchy emerges in which straight debt dominates other financing choices. Equity and convertible debt display significant underpricing. In general, the smaller the probability of loss to outside investors, the more likely the firm is to issue the security and the smaller the security's underpricing. [ABSTRACT FROM AUTHOR]

Recently, the low-rank and sparse (LRS) matrix decomposition has been introduced as an effective mean to solve the multi-view registration. It views each available relative motion as a block element to reconstruct one sparse matrix, which then is used to approximate the low-rank matrix, where global motions can be recovered for multi-view registration. However, this approach is sensitive to the sparsity of the reconstructed matrix and it treats all block elements equally in spite of their varied reliabilities. Therefore, this study proposes an effective approach for multi-view registration by weighted LRS matrix decomposition. On the basis of the inverse symmetry property of relative motions, it first proposes a completion method to reduce the sparsity of the reconstructed matrix. The reduced sparsity of the reconstructed matrix can improve the robustness and efficiency of LRS matrix decomposition. Then, it proposes the weighted LRS matrix decomposition, where each block element is assigned with one estimated weight to denote its reliability. By introducing the weight, more accurate registration results can be efficiently recovered from the estimated low-rank matrix. Experimental results tested on public datasets illustrate the superiority of the proposed approach over the state-of-the-art approaches on robustness, accuracy and efficiency. [ABSTRACT FROM AUTHOR]

Virtual synchronous generator (VSG) control strategy has been widely used in the AC microgrid in recent years. However, the VSG control strategy is lack of the decoupling ability, and its governor control is also lack of the inertia block and speed controller block, resulting in poor dynamic performance, steady-state performance, and low accuracy of the power sharing of the AC microgrid. In this study, a novel VSG control strategy incorporating improved governor control and coupling compensation is proposed to improve the performance of the AC microgrid. Its improved governor control comprises the speed controller and inertia, which can enhance the inertia of the angular frequency and decrease the difference of the governor control between the novel VSG control strategy and diesel generator. Its coupling compensation comprises the angular frequency deviation compensation and voltage deviation compensation, which can reduce the influence of the uncontrollable coupling on the power regulation and increase the degree of freedom of the power regulation. Experimental results validate the effectiveness of the proposed VSG control strategy. [ABSTRACT FROM AUTHOR]

The image fusion method based on sparse representation in the single-scale image domain has produced better fusion results than the classic methods based on multi-scale analysis nowadays. However, due to the limited number of dictionary atoms, it is difficult to provide an accurate description for image details in the sparse-representation-based image fusion methods, and it requires a lot of time. A novel dictionary is constructed with non-subsampled contourlet transform and sparse representation by using the proposed simultaneous strategy. Then the novel dictionary could combine the sparsity attribute of the learning dictionary with a multi-scale feature of non-subsampled contourlet transform. Moreover, the simultaneous strategy is combined with this novel dictionary so that sparse coefficients can be represented with the same dictionary atoms and thus they can be compared in a reasonable and accurate way. Finally, the image fusion method along with this novel dictionary is proposed and named non-subsampled contourlet transform (NSCT)-simultaneous sparse representation (SSR). Experimental results show that the proposed fusion method NSCT-SSR, with its more excellent fusion effect and better anti-noise capability, outperforms the existing fusion methods, which are based on both multi-scale domain and sparse representation in the single-scale image domain. [ABSTRACT FROM AUTHOR]

In this study, a novel two-step model predictive control (MPC) for Hammerstein systems subject to norm-bounded disturbance is addressed. In the first step, the intermediate control law for the linear part of the system is posed as the solution to the unconstrained MPC problem that minimises a quadratic cost function over a given finite time, for which the solution is determined by a novel Riccati iterative equation. In the second step, the actual control move is obtained by solving non-linear algebraic equation group and desaturation. The quadratic boundedness technique is used to specify the stability for closed-loop system with norm-bounded disturbance, and the sufficient conditions for quadratic convergent of the system state are presented. Simulation results demonstrate the effectiveness of the proposed approach to this class of systems. [ABSTRACT FROM AUTHOR]

The classical electrical double layer (EDL) theory explains the interaction between ions and charged soil colloidal particles, playing an importance role in the bioavailability and toxicity of ions in soils, which are of agricultural and environmental concern. A new approach based on extrapolating measurements of suspension Wien effect is suggested to determine the adsorbed ions distribution in the different compartments of the EDL. The new approach was applied to assess Zn2+ distribution in the EDL of Zn-saturated soil colloids. The results showed that more than 84% of Zn2+ was adsorbed via chemical interactions and located in the inner Helmholtz plane layer. The remaining Zn2+ fraction was electrically adsorbed and distributed in the outer Helmholtz plane layer (0.3 to 2.1%) and in the Gouy-Chapman diffuse layer (7.4 to 15.0%). Independently, the results of linear combination fitting of extended x-ray absorption fine structure (EXAFS) spectra indicated that the contents of outer-sphere Zn in one paddy soil and the boggy soil were consistent with the proportions of Zn2+ electrostatically interacting with the soil colloids based on the extrapolation of the suspension Wien effect method, while the contents of outer-sphere Zn in a second paddy soil, the yellow cinnamon soil, and the yellow brown soil was overestimated by the EXAFS method. The approach proposed in this paper to assess specific and electrostatic adsorption deepens our understanding of metal sorption processes in soils and reinforces the adequacy of the Grahame-Stern-Gouy-Chapman model of the EDL to describe the ion distribution in the solid-water interface. [ABSTRACT FROM AUTHOR]