Bioinformatics and RT-PCR analysis of RNA from four Lentinula edodes samples identified 22 different virus-like contigs comprising 15 novel and 3 previously reported viruses. We further investigated ...the Lentinula edodes negative-stranded RNA virus 1 (LeNSRV1) isolated from a symptomatic sample, whose virion is a filamentous particle with a diameter of ~15 nm and a length of ~1200 nm. RT-PCR analysis detected LeNSRV1 in 10 of the 56 Chinese L. edodes core collection strains and 6 of the 22 monokaryotic strains from the L. edodes strain HNZMD. Genetic variation analysis showed that the sequences encoding the nucleocapsid protein (ORF2) from all the aforementioned LeNSRV1 positive strains are very conservative. The results presented here may enrich our understanding of L. edodes virus diversity and the characteristics of LeNSRV1, and will promote further research on virus-host interaction in L. edodes.
•( (1) Identification of 22 different virus-like contigs comprising 15 novel viruses in L. edodes.•Firstly exhibit the viral particles of a negative-strand RNA mymonavirus LeNSRV1.•Firstly exhibit of the occurrence and genetic variation of LeNSRV1 in Chinese Lentinula edodes core collection and sexual basidiospores.
The effects of barrier layer thickness, Al component of barrier layer, and passivation layer thickness of high-resistance Si (111)-based AlGaN/GaN heterojunction epitaxy on the knee-point voltage (
...), saturation current density (
), and cut-off frequency (
) of its high electron mobility transistor (HEMT) are simulated and analyzed. A novel optimization factor
is proposed by considering the various performance parameters of the device to reduce the
and improve the
on the premise of ensuring the
. Based on this factor, the optimized AlGaN/GaN epitaxial structure was designed with a barrier layer thickness of 20 nm, an Al component in the barrier layer of 25%, and a SiN passivation layer of 6 nm. By simulation, when the gate voltage V
is 0 V, the designed device with a gate length of 0.15 μm, gate-source spacing of 0.5 μm, and gate-drain spacing of 1 μm presents a high
of 750 mA/mm and a low
of 2.0 V and presents
and maximum frequency (
) as high as 110 GHz and 220 GHz, respectively. The designed device was fabricated and tested to verify the simulation results. We demonstrated the optimization factor
can provide an effective design method for follow-up high-frequency and low-voltage applications of GaN devices.
AlGaN/GaN-Si based MIS-HEMTs are considered as the popular candidates for application in the 5G communication system due to their competitive characteristics and low cost. Ohmic contact, as an ...important fabrication process, significantly affects the performance of the device. In this study, the ohmic contact process, including the SiN passivation layer etching, surface treatment, and barrier layer etching, was studied in detail in order to effectively optimize the device performance. It is observed that the sample with the SiN passivation layer etched by the magnetic neutral loop discharge (NLD) resulted in a lower contact resistance as compared to the reaction ion etching (RIE). The sample surface treated with the O plasma and pickled in the HCl:H2O = 1:10 liquid could effectively remove the pollutants and oxides from the surface, thus, correspondingly presenting a lower ohmic contact resistance as compared to the N2 plasma. Meanwhile, an optimum etching depth was developed with the ICP process for 6 min with an etching speed of 1.6 nm/min. A contact resistance of <inline-formula> <tex-math notation="LaTeX">0.76~\Omega \cdot \text {mm} </tex-math></inline-formula> and square resistance of 274.63 ohm/sq were observed under the above-mentioned optimized ohmic contact process. The AlGaN/GaN-Si MIS-HEMT with gate length of <inline-formula> <tex-math notation="LaTeX">0.5~\mu \text{m} </tex-math></inline-formula>, gate-source space of <inline-formula> <tex-math notation="LaTeX">1~\mu \text{m} </tex-math></inline-formula>, gate-drain space of <inline-formula> <tex-math notation="LaTeX">2.5~\mu \text{m} </tex-math></inline-formula>, and gate width of <inline-formula> <tex-math notation="LaTeX">100~\mu \text{m} </tex-math></inline-formula> was fabricated using the optimized process. A saturation current density of 794.30 mA/mm and the maximum transconductance of 16.86 mS were observed. The findings in this study provide the experimental basis for the manufacturing of AlGaN/GaN-Si based MIS-HEMTs for RF applications.
A high-resistance Si-based AlInGaN/GaN heterojunction epitaxy specifying AlN/AlGaN laminated buffer layers and AlInGaN barrier layer with 45% Al composition was successfully produced to show a high ...electron density of <inline-formula> <tex-math notation="LaTeX">1.93\times10 </tex-math></inline-formula> 13 cm −2 and mobility of 2829.24 cm 2 /Vs and based on which a novel varistor is proposed in this work. The varistor is composed with a narrow groove etched into the GaN channel and Ti/Al/Ni/Au (20/130/50/50 nm) metal electrodes attached to the epitaxy surface. The processes to fabricate the varistor were investigated in-depth, including a narrow groove etching based on dry-wet hybrid cyclic etching technology employing oxygen plasma and hydrochloric acid and an optimized metal electrodes ohmic contact process based on HCl:H 2 O = 1:10 liquid surface treatment and annealing at 875 °C to achieve a low contact resistance of <inline-formula> <tex-math notation="LaTeX">0.45 \Omega \cdot </tex-math></inline-formula> mm. The device with a groove width of <inline-formula> <tex-math notation="LaTeX">3 ~\mu \text{m} </tex-math></inline-formula> and length of <inline-formula> <tex-math notation="LaTeX">600 ~\mu \text{m} </tex-math></inline-formula> exhibits typical varistor characteristics with opening voltage (<inline-formula> <tex-math notation="LaTeX">V_{{\mathrm {ON}}} </tex-math></inline-formula>) of 33.8 V and a high nonlinear coefficient of 82.97 in the current range from 1 to 10 mA. The <inline-formula> <tex-math notation="LaTeX">V_{{\mathrm {ON}}} </tex-math></inline-formula> value of the varistors is directly proportional to the narrow groove width with a scaling coefficient of 10.18 V/<inline-formula> <tex-math notation="LaTeX">\mu \text{m} </tex-math></inline-formula>, which means <inline-formula> <tex-math notation="LaTeX">V_{{\mathrm {ON}}} </tex-math></inline-formula> can be adjusted by altering the width of the groove. The varistor with a simple structure could be used in GaN on-chip integrated switches, electro-static discharge (ESD) protection, and other applications.
HR Si(111)-based AlGaN/GaN metal insulator semiconductor high electron mobility transistor (MIS-HEMT) for 5G mobile communication at N28 700 MHz band is proposed in this paper. The device is ...ingeniously designed with a symmetrical dual-column multi-finger grid array structure. In addition, the device is designed with an MIS gate with a 6 nm SiN dielectric film to suppress the leakage current and a source field plate to suppress the current collapse effect. The fabrication process of the device is studied in detail, including the epitaxial surface treatment, F ion implantation isolation, ohmic contact, electron beam lithography gate process, surface passivation, and source field plate. A device with a gate length of 0.25 μm, gate-source space of 1 μm, a gate width of 1200 μm (the number of gate fingers is 12 with a single-finger gate width of 100 μm), and source field plate length of 0.2 μm is fabricated successfully. Results of electrical tests show that the HEMT device has a threshold voltage of about −7.5 V, a low knee voltage of about 4 V, a high saturation drain current density of 750 mA/mm, and a gate leakage current as low as less than 160 pA at the gate bias of 0 V. At the frequency band of 703–803 MHz, with low bias control of 10 V, the S21 of HEMT is about 5.923–7.261 dB, the gain flatness is 1.338 dB, the current gain is about 27.3 dB, and the stability factor is more than 1. This device would be a good candidate for future 5G low-frequency and low-voltage-control applications.
Graph-based image segmentation techniques generally represent the problem in terms of a graph. In this work, we present a novel graph, called the directional nearest neighbor graph. The construction ...principle of this graph is that each node corresponding to a pixel in the image is connected to a fixed number of nearest neighbors measured by color value and the connected neighbors are distributed in four directions. Compared with the classical grid graph and the nearest neighbor graph, our method can capture low-level texture information using a less-connected edge topology. To test the performance of the proposed method, a comparison with other graph-based methods is carried out on synthetic and real-world images. Results show an improved segmentation for texture objects as well as a lower computational load.
Early‐onset preeclampsia (ePE) originates from abnormal implantation and placentation that involves trophoblast invasion, but its pathophysiology is not entirely understood. N6‐methyladenosine (m6A) ...regulators mediate the progression of various cancers. The invasiveness of trophoblast cells is similar to that of tumor cells. However, little is known regarding the potential role of m6A modification in ePE and the underlying mechanism. This study aimed to explore the m6A level in placental tissue samples collected from ePE patients and to investigate whether m6A modification was an essential part of PE pathogenesis. The m6A level in placental tissue samples of 80 PE participants was examined. MeRIP‐microarray, RNA‐Seq, luciferase reporter assay, and RNA immunoprecipitation chip (RIP) assay were performed. The m6A level in the ePE group was significantly reduced compared with the control group. Wilms' tumor 1‐associating protein (WTAP) regulated trophoblast cell migration and invasion. Mechanistically, the high mobility group nucleosomal binding domain 3 (HMGN3) gene was a target gene of WTAP in trophoblast (p < .05). WTAP enhanced the stability of HMGN3 mRNA through binding with its 3’‐UTR m6A site(+485A, +522A). HMGN3 was recognized by m6A recognition protein insulin‐like growth factor 2 mRNA‐binding protein 1 (IGF2BP1), which was inhibited when knocking down WTAP. Both m6A and WTAP levels were downregulated in ePE. The m6A modification mediated by WTAP/IGF2BP1/HMGN3 axis might contribute to abnormal trophoblast invasion. Our work provided a foundation for further exploration of RNA epigenetic regulatory patterns in ePE, and indicated a new treatment strategy for ePE.
We have fabricated high porosity, low shrinkage carbon nanotubes (CNTs)/aramid nanofibers (ANF)/polyimide (PI) aerogels with efficient electromagnetic (EM) wave absorption, good sound insulation, ...high thermal insulation, and additional anti-icing and infrared stealth properties. Owing to the combination of the functionalities of the individual components, the hybrid aerogels show considerable application potential in the fields of stealth materials, construction materials, and smart wearable materials. More importantly, this hybrid aerogels ensure efficient absorption of EM waves in the temperature range of 25–400 °C. Such CNTs/ANF/PI aerogels are expected to achieve EM protection in harsh thermal environments.
Display omitted
•A multifunctional CNTs-based hybrid aerogel was fabricated.•Efficient electromagnetic wave attenuation capability in 25–400 °C.•Sound absorption, thermal insulation, and infrared stealth were developed.•This work demonstrates the applicability potential in harsh thermal environments.
In the complex engineering applications of electromagnetic (EM) wave-absorbing materials, it is insufficient for these materials to exhibit only efficient EM wave attenuation ability. EM wave-absorbing materials featuring numerous multifunctional properties are increasingly attractive for next-generation wireless communication and smart devices. Herein, we constructed a lightweight and robust multifunctional hybrid aerogel consisting of carbon nanotubes/aramid nanofibers/polyimide with low shrinkage and high porosity. The hybrid aerogels exhibit excellent EM wave attenuation, with an effective absorption bandwidth covering the entire X-band from 25 °C to 400 °C. The conductive loss capacity of the hybrid aerogel is enhanced under thermal drive, which results in an enhanced ability to attenuate EM waves, as evidenced by the fact that the best-fit thickness drops from 5.3 to 3.6 mm with increasing temperature. In addition, the hybrid aerogels are capable to efficiently absorb sound waves, with an average absorption coefficient as high as 0.86 at 1–6.3 kHz, and they exhibit superior thermal insulation properties, with a thermal conductivity as low as 41 ± 2 mW/mK. They are thus suitable for applications in the anti-icing and infrared stealth fields. The prepared multifunctional aerogels have considerable potential for EM protection, noise reduction, and thermal insulation in harsh thermal environments.
In this article, we review the available evidence and explore the association between air pollution and insulin resistance (IR) using meta-analytic techniques. Cohort studies published before January ...2018 were selected through English-language literature searches in nine databases. Six cohort studies were included in our sample, which assessed air pollutants including PM
(particulate matter with an aerodynamic diameter less than or equal to 2.5 μm), NO₂(nitrogen dioxide), and PM
(particulate matter with an aerodynamic diameter less than 10 μm). Percentage change in insulin or insulin resistance associated with air pollutants with corresponding 95% confidence interval (CI) was used to evaluate the risk. A pooled effect (percentage change) was observed, with a 1 μg/m³ increase in NO₂ associated with a significant 1.25% change (95% CI: 0.67, 1.84; I² = 0.00%,
= 0.07) in the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and a 0.60% change (95% CI: 0.17, 1.03; I² = 30.94%,
= 0.27) in insulin. Similar to the analysis of NO₂, a 1 μg/m³ increase in PM
was associated with a significant 2.77% change (95% CI: 0.67, 4.87; I² = 94.98%,
< 0.0001) in HOMA-IR and a 2.75% change in insulin (95% CI: 0.45, 5.04; I² = 58.66%,
= 0.057). No significant associations were found between PM
and insulin resistance biomarkers. We conclude that increased exposure to air pollution can lead to insulin resistance, further leading to diabetes and cardiometabolic diseases. Clinicians should consider the environmental exposure of patients when making screening and treatment decisions for them.
Dysfunctional integration of distributed brain networks is believed to be the cause of schizophrenia, and resting-state functional connectivity analyses of schizophrenia have attracted considerable ...attention in recent years. Unfortunately, existing functional connectivity analyses of schizophrenia have been mostly limited to linear associations.
The objective of the present study is to evaluate the discriminative power of non-linear functional connectivity and identify its changes in schizophrenia.
A novel measure utilizing the extended maximal information coefficient was introduced to construct non-linear functional connectivity. In conjunction with multivariate pattern analysis, the new functional connectivity successfully discriminated schizophrenic patients from healthy controls with relative higher accuracy rate than the linear measure.
We found that the strength of the identified non-linear functional connections involved in the classification increased in patients with schizophrenia, which was opposed to its linear counterpart. Further functional network analysis revealed that the changes of the non-linear and linear connectivity have similar but not completely the same spatial distribution in human brain.
The classification results suggest that the non-linear functional connectivity provided useful discriminative power in diagnosis of schizophrenia, and the inverse but similar spatial distributed changes between the non-linear and linear measure may indicate the underlying compensatory mechanism and the complex neuronal synchronization underlying the symptom of schizophrenia.
PDF
