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Highly efficient growth of a centimeter‐scale MoS2 monolayer film by oxide scale sublimation chemical vapor deposition (OSSCVD) in a time as short as 60 s is reported. Benefiting from the superior catalytic ability of Dragontrail glass (DT‐glass) substrate and the controlled large vapor supersaturation of the molybdenum source, the ultrafast deposition of MoS2 is realized with maintaining large‐sized single‐crystalline domains over 20 µm at maximum in the film. It is comparable to those reported for MoS2 grown in tens of minutes and even hours. Similar to the face‐to‐face precursor feed route, the gas‐controlled OSSCVD with a showerhead configuration facilitates a homogeneous and controllable source supply. It enables high‐quality monolayer MoS2 film deposition on 2 × 2 cm2 DT‐glass with centimeter‐scale uniformity confirmed by microscopic, spectroscopic, and electrical characterizations. Back‐gate MoS2 field‐effect transistors fabricated on polycrystalline continuous film exhibit the maximum field‐effect mobility of 5.1 cm2 V−1s−1 and a peak Ion/Ioff ratio of 5 × 108. They reach 40 cm2 V−1 s−1 and 1.2 × 109, respectively, on single‐crystalline domains. These results are even greater than those for MoS2 grown using 1–2 orders of magnitude longer deposition time and higher temperatures. This study highlights the opportunities for low‐cost high‐throughput production of large‐area high‐quality monolayer MoS2. [ABSTRACT FROM AUTHOR]

Background: Patients with obstructive sleep apnea (OSA) are more likely to suffer from hypertension. At the same time, the serum levels of matrix metalloproteinase‐9 (MMP‐9) and nitric oxide (NO) in patients with OSA are also changed in OSA patients. We investigated the correlation between serum levels of MMP‐9, NO in patients with OSA and their association with hypertension in those patients, and the effects of continuous positive airway pressure therapy (CPAP) on these serum biomarkers and blood pressure. Methods: Serum MMP‐9 and NO levels and blood pressure of 57 patients with newly diagnosed OSA and 30 controls were measured; among them, 30 patients with moderate to severe OSA underwent 3‐month CPAP treatment. Results: In comparison to the control group, the MMP‐9 serum levels were higher (232.8 ± 103.2 ng/ml versus 161.6 ± 56.5 ng/ml, p <.001*), there was no statistical significance difference among serum NO (26.7 ± 9.1 IU/ml versus 31.0 ± 11.7 IU/ml, p =.06), and MMP‐9 was negatively correlated to NO, especially in patients with hypertension (r = −.644, p =.02*). MMP‐9, NO, and blood pressure were significantly recovered in the patients with OSA after CPAP treatment for 3 months (p <.05*). Conclusion: The MMP‐9 level and the NO level were altered in OSA patients. The relationship between the two especially in patients with hypertension suggests the potential mechanism of OSA‐induced hypertension. [ABSTRACT FROM AUTHOR]

A newly developed oxide scale sublimation chemical vapor deposition (OSSCVD) technique for 2D MoS2 growth is reported. Gaseous MoO3, which is supplied separately from H2S, can be generated in situ by flowing O2 over Mo metal with oxidation and sublimation processes. In this method, particularly, controllably and abruptly modulating the supply of MoO3 is achievable by precisely tuning O2 flow. Having appropriate conditions, where the generation rate of MoO3 on the Mo metal surface is not larger than its sublimation rate, is critical to enable stable growth. Otherwise, MoS2 deposition can be caused by accumulated MoO3 on the metal surface, regardless of oxygen supply. Proof‐of‐concept experiments with varied process parameters are conducted, confirming OSSCVD enables MoS2 growth with significantly improved flexibility, controllability, and reproducibility relative to conventional powder‐source CVD. By utilizing alkali‐aluminosilicate glass, Dragontrail, as catalytic substrate, single‐crystalline MoS2 triangular domains as large as 25 µm are obtained, followed by a fully covered monolayer on Dragontrail in 25 min. Substrate pretreatment by H2S yields enlarged domain size and reduced domain density, owning to the extracted alkali metals from Dragontrail into the growth zone. The study opens new avenues for the controllable growth of high‐quality MoS2 and other transition metal dichalcogenides. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) transition metal dichalcogenides (TMDCs) with unique electrical properties are fascinating materials used for future electronics. However, the strong Fermi level pinning effect at the interface of TMDCs and metal electrodes always leads to high contact resistance, which seriously hinders their application in 2D electronics. One effective way to overcome this is to use metallic TMDCs or transferred metal electrodes as van der Waals (vdW) contacts. Alternatively, using highly conductive doped TMDCs will have a profound impact on the contact engineering of 2D electronics. Here, a novel chemical vapor deposition (CVD) using mixed molten salts is established for vapor–liquid–solid growth of high‐quality rhenium (Re) and vanadium (V) doped TMDC monolayers with high controllability and reproducibility. A tunable semiconductor to metal transition is observed in the Re‐ and V‐doped TMDCs. Electrical conductivity increases up to a factor of 108 in the degenerate V‐doped WS2 and WSe2. Using V‐doped WSe2 as vdW contact, the on‐state current and on/off ratio of WSe2‐based field‐effect transistors have been substantially improved (from ≈10–8 to 10–5 A; ≈104 to 108), compared to metal contacts. Future studies on lateral contacts and interconnects using doped TMDCs will pave the way for 2D integrated circuits and flexible electronics. [ABSTRACT FROM AUTHOR]

Abstract: Laryngeal cancer is one of the most common head and neck malignant tumors and is commonly resistant to X‐ray‐based radiotherapy. NF‐κB interacting lncRNA (NKILA) has been reported to serve as a tumor suppressor in several cancers through combining with NF‐κB: IκB complex thereby inhibiting NF‐κB activation. Herein, we demonstrated a low NKILA expression in laryngeal cancer and its correlation with shorter overall survival in patients with laryngeal cancer. NKILA serves as a tumor suppressor in laryngeal cancer by suppressing laryngeal cancer cell viability and migration, whereas promoting cell apoptosis; NKILA knockdown reverses the cytotoxicity of X‐ray radiation on laryngeal cancer cells through combining with NF‐κB: IκB complex to inhibit IκB phosphorylation, inhibit p65 nuclear translocation, and finally inhibit NF‐κB activation. NF‐κB binds to the promoter region of NKILA to activate its transcriptional activity, upregulated NKILA then inhibits IκB phosphorylation and NF‐κB activation, thus forming a negative feedback loop to sensitize laryngeal cancer cell to X‐ray radiation. In conclusion, NKILA can serve as a promising agent of enhancing the cytotoxicity of X‐ray radiation on laryngeal cancer and addressing the radioresistance of laryngeal cancer. [ABSTRACT FROM AUTHOR]

Abstract: Defects and their spatial distribution are crucial factors in controlling the electronic and optical properties of semiconductors. By using scanning transmission electron microscopy and electron energy loss spectroscopy, the type of impurities/defects in WS2 subdomains with different optical properties is successfully assigned. A higher population of Cr impurities is found in the W‐terminated edge domain, while the S‐terminated domain contains more Fe impurities, in accordance with the luminescence characteristics of chemical‐vapor‐grown WS2 of a hexagonal shape. In agreement with the first‐principles calculations, the domains with Cr substitutional dopants exhibit strong trion emission. Fe atoms tend to gather into trimer configuration and introduce deep acceptor levels which compensate the n‐type doping and suppress trion emission. It is also discovered that the domain with higher luminescence but smaller defect concentration tends to get oxidized more rapidly and degrade the 2D structure with many triangular holes. Excitons tend to accumulate at the edges of the oxidized triangular holes and results in enhanced PL emission. The findings indicate that choosing stable elements as dopant and controlling the number of specific edge structures within a crystal domain of 2D transitional metal dichalcogenides can be a new route to improve the optical properties of these materials. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) can be accumulated into the human body via food intake and inhalation. Numerous studies indicated that BPA can trigger the tumorigenesis and progression of cancer cells. Laryngeal cancer cells can be exposed to BPA directly via food digestion, while there were very limited data concerning the effect of BPA on the development of laryngeal squamous cell carcinoma (LSCC). Our present study revealed that nanomolar BPA can trigger the proliferation of LSCC cells. Bisphenol A also increased the in vitro migration and invasion of LSCC cells and upregulated the expression of matrix metallopeptidase 2. Among various chemokines tested, the expression of IL-6 was significantly increased in LSCC cells treated with BPA for 24 hours. Neutralization antibody of IL-6 or si-IL-6 can attenuate BPA-induced proliferation and migration of LSCC cells. Targeted inhibition of G protein-coupled estrogen receptor, while not estrogen receptor (ERα), abolished BPA-induced IL-6 expression, proliferation, and migration of LSCC cells. The increased IL-6 can further activate its downstream signal molecule STAT3, which was evidenced by the results of increased phosphorylation and nuclear translocation of STAT3, while si-IL-6 and si-GPER can both reverse BPA-induced activation of STAT3. Collectively, our present study revealed that BPA can trigger the progression of LSCC via GPER-mediated upregulation of IL-6. Therefore, more attention should be paid for the BPA exposure on the development of laryngeal cancer. [ABSTRACT FROM AUTHOR]

Nucleotide excision repair is a well-conserved DNA repair pathway that removes bulky and/or helix-distorting DNA lesions, such as UV-induced cyclobutane pyrimidine dimers and pyrimidine (6-4) pyrimidone photoproducts. Transcription-coupled repair ( TCR) is a subpathway of nucleotide excision repair that is dedicated to rapid removal of DNA lesions in the transcribed strand of actively transcribed genes. In eukaryotic cells, TCR is triggered by RNA polymerase II ( RNAP II). Rad26, a DNA-dependent ATPase, Rpb9, a nonessential subunit of RNAP II, and Sen1, a 5′ to 3′ RNA/ DNA and DNA helicase, have been shown to facilitate TCR in Saccharomyces cerevisiae. In contrast, a number of factors have also been found to repress TCR in the yeast. These TCR repressors include Rpb4, another nonessential subunit of RNAP II, Spt4/5, a transcription elongation factor complex, and the RNAP II-associated factor 1 complex ( PAFc). It appears that the eukaryotic TCR process involves intricate interplays of RNAP II with TCR facilitators and repressors. In this minireview, we summarize recent advances in TCR in S. cerevisiae. [ABSTRACT FROM AUTHOR]

Polycomb group ( Pc G) proteins are gene repressors that help to maintain cellular identity during development via chromatin remodeling. Fertilization-independent endosperm ( FIE), a member of the Pc G complex, operates extensively in plant development, but its role in rice has not been fully investigated to date., We report the isolation and characterization of a Pc G member in rice, which was designated Os FIE2 for Oryza sativa Fertilization- Independent Endosperm 2. Os FIE2 is a single-copy gene in the rice genome and shows a universal expression pattern., The Os FIE2 RNAi lines displayed pleiotropic phenotypes in vegetative and reproductive organ generation. In unfertilized lines, endosperm formation could be triggered without embryo formation, which indicates that FIE is indeed involved in the suppression of autonomous endosperm development in rice. Furthermore, lateral root generation was promoted early in the roots of Os FIE2 RNAi lines, whereas the primary root was premature and highly differentiated. As the root tip stem cell differentiated, QHB, the gene required for stem cell maintenance in the quiescent center, was down-regulated., Our data suggest that the Os FIE2- Pc G complex is vital for rice reproduction and endosperm formation. Its role in stem cell maintenance suggests that the gene is functionally conserved in plants as well as animals. [ABSTRACT FROM AUTHOR]

Rpb9, a non-essential subunit of RNA polymerase H, mediates a transcription-coupled repair (TCR) sub-pathway in Saccharomyces cerevisiae. This subpathway initiates at the same upstream site as the previously identified Rad26 subpathway. However, the Rpb9 subpathway operates more effectively in the coding region than in the region upstream of the transcription start site, whereas the Rad26 subpathway operates equally in the two regions. Rpb4, another non-essential subunit of RNA polymerase II, plays a dual role in regulating the two subpathways, suppressing the Rpb9 subpathway and facilitating the Rad26 subpathway. Simultaneous deletion of RPB9 and RAD26 genes completely abolishes TCR in both the coding and upstream regions, indicating that no other TCR subpathway exists in RNA polymerase II- transcribed genes. [ABSTRACT FROM AUTHOR]

Chemical Vapor Deposition: Tunable Doping of Rhenium and Vanadium into Transition Metal Dichalcogenides for Two-Dimensional Electronics (Adv. Sci. 11/2021) A new strategy using mixed salts for chemical vapor deposition of tunable Re- and V-doped 2D transition metal dichalcogenides (TMDCs) is realized by Shisheng Li, Takaaki Taniguchi, and co-workers, as described in article number 2004438. By applying the highly conductive V-doped WSe SB 2 sb as van der Waals contacts for 2D WSe SB 2 sb based field-effect transistor, the on-state current and on/off ratio are substantially improved, compared to the metal contacts. [Extracted from the article]

Purpose: To estimate laryngopharyngeal reflux (LPR) changes after uvulopalatopharyngoplasty (UPPP) for obstructive sleep apnea (OSA) using the reflux symptom index (RSI) and reflux finding score (RFS) questionnaires. Methods: A total of 91 participants were recruited and divided into three groups: control (n = 27), OSA mild to moderate (n = 29), and OSA severe (n = 35) groups according to polysomnography. All participants completed the preoperative RSI, and underwent blinded evaluation on videolaryngoscopy using the RFS questionnaire. Thirty‐four OSA patients who underwent UPPP surgery completed postoperative polysomnography and questionnaires again after a 6‐month follow‐up. Results: The RSI score and RFS were higher in patients with OSA than in those without OSA. Patients with severe OSA also had a higher RSI score and RFS than those with mild to moderate OSA. Apnea and hypopnea index degree and percentage of recording time for <90% oxygen saturation showed positive correlation with LPR symptoms. But the lowest blood oxygen saturation during the recording time was negatively correlated with LPR symptoms. The mean RSI score and RFS before UPPP surgery were 15.88 ± 4.85 and 13.18 ± 4.80, after surgery decreasing to 9.53 ± 4.16 and 8.65 ± 4.87, respectively (P <.05). In 25 patients where surgery was successful, RSI scores, RFSs and individual RSI variables decreased after surgery. Conclusions: LPR symptoms are common among OSA patients, and the coexistence of OSA and LPR cannot be ignored. Successful UPPP surgery potentially reduces LPR symptoms and improves laryngoscopic signs by alleviating sleep respiratory disorders. Level of Evidence: 3. [ABSTRACT FROM AUTHOR]

Malignant tumors are one of the leading causes of death which impose an increasingly heavy burden on all countries. Therefore, the establishment of research models that closely resemble original tumor characteristics is crucial to further understanding the mechanisms of malignant tumor development, developing safer and more effective drugs, and formulating personalized treatment plans. Recently, organoids have been widely used in tumor research owing to their advantages including preserving the structure, heterogeneity, and cellular functions of the original tumor, together with the ease of manipulation. This review describes the history and characteristics of tumor organoids and the synergistic combination of three‐dimensional (3D) culture approaches for tumor organoids with emerging technologies, including tissue‐engineered cell scaffolds, microfluidic devices, 3D bioprinting, rotating wall vessels, and clustered regularly interspaced short palindromic repeats‐CRISPR‐associated protein 9 (CRISPR‐Cas9). Additionally, the progress in research and the applications in basic and clinical research of tumor organoid models are summarized. This includes studies of the mechanism of tumor development, drug development and screening, precision medicine, immunotherapy, and simulation of the tumor microenvironment. Finally, the existing shortcomings of tumor organoids and possible future directions are discussed. [ABSTRACT FROM AUTHOR]

Distorted octahedral T′ phase of MoTe2 has recently attracted significant interest due to its predicted topological states and novel charge transport properties. Here, we report a nondestructive method for determining the crystal orientation of few-layer T′-MoTe2 flakes by polarized Raman spectroscopy. The experimentally observed Raman modes are assigned to eigenmodes of vibrations predicted by density functional theory calculations. Polarized Raman measurements reveal four distinct types of angle-dependent intensity variations. From group theory, it can be deduced that the intensity of the Bg mode reaches a maximum in the [ABSTRACT FROM AUTHOR]

Summary: Clubroot is one of the most important diseases for many important cruciferous vegetables and oilseed crops worldwide. Different clubroot resistance (CR) loci have been identified from only limited species in Brassica, making it difficult to compare and utilize these loci. European fodder turnip ECD04 is considered one of the most valuable resources for CR breeding. To explore the genetic and evolutionary basis of CR in ECD04, we sequenced the genome of ECD04 using de novo assembly and identified 978 candidate R genes. Subsequently, the 28 published CR loci were physically mapped to 15 loci in the ECD04 genome, including 62 candidate CR genes. Among them, two CR genes, CRA3.7.1 and CRA8.2.4, were functionally validated. Phylogenetic analysis revealed that CRA3.7.1 and CRA8.2.4 originated from a common ancestor before the whole‐genome triplication (WGT) event. In clubroot susceptible Brassica species, CR‐gene homologues were affected by transposable element (TE) insertion, resulting in the loss of CR function. It can be concluded that the current functional CR genes in Brassica rapa and non‐functional CR genes in other Brassica species were derived from a common ancestral gene before WGT. Finally, a hypothesis for CR gene evolution is proposed for further discussion. [ABSTRACT FROM AUTHOR]

Accurate design of the 2D metal–semiconductor (M–S) heterostructure via the covalent combination of appropriate metallic and semiconducting materials is urgently needed for fabricating high‐performance nanodevices and enhancing catalytic performance. Hence, the lateral epitaxial growth of M–S SnxMo1−xS2/MoS2 heterostructure is precisely prepared with in situ growth of metallic SnxMo1−xS2 by doping Sn atoms at semiconductor MoS2 edge via one‐step chemical vapor deposition. The atomically sharp interface of this heterostructure exhibits clearly distinguished performance based on a series of characterizations. The oxygen evolution photoelectrocatalytic performance of the epitaxial M–S heterostructure is 2.5 times higher than that of pure MoS2 in microreactor, attributed to the efficient electron–hole separation and rapid charge transfer. This growth method provides a general strategy for fabricating seamless M–S lateral heterostructures by controllable doping heteroatoms. The M–S heterostructures show increased carrier migration rate and eliminated Fermi level pinning effect, contributing to their potential in devices and catalytic system. [ABSTRACT FROM AUTHOR]

Summary: Drought is an abiotic stress that affects plant growth, and lipids are the main economic factor in the agricultural production of oil crops. However, the molecular mechanisms of drought response function in lipid metabolism remain little known. In this study, overexpression (OE) of different copies of the drought response genes LEA3 and VOC enhanced both drought tolerance and oil content in Brassica napus and Arabidopsis. Meanwhile, seed size, membrane stability and seed weight were also improved in OE lines. In contrast, oil content and drought tolerance were decreased in the AtLEA3 mutant (atlea3) and AtVOC‐RNAi of Arabidopsis and in both BnLEA‐RNAi and BnVOC‐RNAi B. napus RNAi lines. Hybrids between two lines with increased or reduced expression (LEA3‐OE with VOC‐OE, atlea3 with AtVOC‐RNAi) showed corresponding stronger trends in drought tolerance and lipid metabolism. Comparative transcriptomic analysis revealed the mechanisms of drought response gene function in lipid accumulation and drought tolerance. Gene networks involved in fatty acid (FA) synthesis and FA degradation were up‐ and down‐regulated in OE lines, respectively. Key genes in the photosynthetic system and reactive oxygen species (ROS) metabolism were up‐regulated in OE lines and down‐regulated in atlea3 and AtVOC‐RNAi lines, including LACS9,LIPASE1,PSAN,LOX2 and SOD1. Further analysis of photosynthetic and ROS enzymatic activities confirmed that the drought response genes LEA3 and VOC altered lipid accumulation mainly via enhancing photosynthetic efficiency and reducing ROS. The present study provides a novel way to improve lipid accumulation in plants, especially in oil production crops. [ABSTRACT FROM AUTHOR]

The maternal-to-zygotic transition (MZT) is characterized by the turnover of zygote development from maternal to zygotic control, and has been extensively studied in animals. A majority of studies have suggested that early embryogenesis is maternally controlled and that the zygotic genome remains transcriptionally inactive prior to the MZT. However, little is known about the MZT in higher plants, and its timing and impact remain uncharacterized. Here, we constructed cDNA libraries from tobacco ( Nicotiana tabacum) egg cells, zygotes and two-celled embryos for gene expression profiling analysis, followed by RT-PCR confirmation. These analyses, together with experiments using zygote microculture coupled with transcription inhibition, revealed that a marked change in transcript profiles occurs approximately 50 h after fertilization, and that the MZT is initiated prior to zygotic division in tobacco. Although maternal transcripts deposited in egg cells support several early developmental processes, they appear to be insufficient for zygotic polar growth and subsequent cell divisions. Thus, we propose that de novo transcripts are probably required to trigger embryogenesis in later zygotes in tobacco. [ABSTRACT FROM AUTHOR]

Crystal phase control still remains a challenge for the precise synthesis of 2D layered metal dichalcogenide (LMD) materials. The T′ phase structure has profound influences on enhancing electrical conductivity, increasing active sites, and improving intrinsic catalytic activity, which are urgently needed for enhancing hydrogen evolution reaction (HER) activity. Theoretical calculations suggest that metastable T′ phase 2D Sn1−xWxS2 alloys can be formed by combining W with 1T tin disulfide (SnS2) as a template to achieve a semiconductor‐to‐metallic transition. Herein, 2D Sn1−xWxS2 alloys with varying x are prepared by adjusting the molar ratio of reactants via hydrothermal synthesis, among which Sn0.3W0.7S2 displays a maximum of concentration of 81% in the metallic phase and features a distorted octahedral‐coordinated metastable 1T′ phase structure. The obtained 1T′‐Sn0.3W0.7S2 has high intrinsic electrical conductivity, lattice distortion, and defects, showing a prominently improved HER catalytic performance. Metallic Sn0.3W0.7S2 coupled with carbon black exhibits at least a 215‐fold improvement compared to pristine SnS2. It has excellent long‐term durability and HER activity. This work reveals a general phase transition strategy by using T phase materials as templates and merging heteroatoms to achieve synthetic metastable phase 2D LMDs that have a significantly improved HER catalytic performance. [ABSTRACT FROM AUTHOR]