A Novel Allele in the Promoter of Wx Decreases Gene Expression and Confers Lower Apparent Amylose Contents in Japonica Rice (Oryza sativa L.).

Wx is the key gene that controls amylose content (AC), and various alleles have been found in rice populations. Wxb is the major allele in japonica and produces moderate AC (15~18%). It was recently found that editing the promoter of Wx could produce a series of alleles that have different Wx activities. Although some studies have edited the promoter, few studies have focused on the natural variations in Wx. Here, we used the Rice3K database to investigate variations in the Wx promoter and found that the allele Wx1764178 (A/G) has a higher LD (linkage disequilibrium) with the two key SNPs (1765751, T/G; 1768006, A/C), which could produce different Wx alleles and influence AC, as reported previously. Further study showed that the Wx1764178 allele (A/G) is functional and influences the expression of Wx positively. Editing the A allele using CRISPR‒Cas9 produced 36 and 3 bp deletions and caused a decrease in the expression of Wx. The apparent amylose content (AAC) in the edited lines was decreased by 7.09% and 11.50% compared with that of the wild type, which was the japonica variety Nipponbare with Wxb and the A allele at 1764178, while a complementary line with the G allele showed a lower AAC than the A allele with no effect on other agronomic traits. The AAC of the edited lines showed a higher increase than that of the wild type (Nipponbare, Wxb) in low-nitrogen conditions relative to high-nitrogen conditions. We also developed a dCAPS marker to identify the allele and found that the G allele has widely been used (82.95%) in japonica-bred varieties from Jiangsu Province, China. Overall, we found a functional allele (Wx1764178, A/G) in the Wx promoter that could affect AAC in japonica cultivars and be developed as markers for quality improvement in rice breeding programs.

Enhancement of multilayer lithium storage in a ß12-borophene/graphene heterostructure with built-in dipoles.

The combination of borophene with a supporting metallic layer is beneficial in stabilizing its structure and promoting its application in energy storage. Here, through first-principles calculations, we screen a ß12-borophene/graphene (ß12-B/G) heterostructure with superior structural integrity, strong interlayer binding, and high thermodynamic stability among different B/G heterostructures. Besides, it is noteworthy that ß12-B/G has been recently synthesized, further opening the possibility of expanding its use in energy storage. Then the selected target is systematically investigated as an anode material for lithium-ion batteries (LIBs). Compared with each monolayer component, multiple lithium-ion adsorption is achieved in the ß12-B/G heterostructure, resulting in an ultra-high theoretical specific capacity of 2267 mA h g-1. In addition, a lower diffusion energy barrier indicates faster electron transport and lithium-ion diffusion in the ß12-B/G heterostructure. Notably, the multilayer lithium adsorption avoids the formation of dendritic deposits, as evidenced by complete ionization of the cationic layers. Moreover, the disparity in the work functions of the individual layers gives rise to a built-in dipole in ß12-B/G, further enhancing the multilayer lithium storage and ion migration. All these results suggest that the construction of borophene-based heterostructures with built-in dipoles is a feasible way to design high-performance LIB anode materials.

A weakened Fermi level pinning induced adsorption energy non-charge-transfer mechanism during O2 adsorption in silicene/graphene heterojunctions.

Understanding the mechanisms of gas adsorption on a solid surface and making this process tunable are of great significance in fundamental science and industrial applications. Bond creation and charge transfer are often used to explain the origin of adsorption energy (Ead). However, in this study, a new mechanism is observed in O2 adsorption on pure silicene (PS) and silicene/graphene heterojunction (SGH) surfaces, in which the charge distribution remains almost unchanged, but Ead still has a significant change in the order of 0.3 eV. The weakened Fermi level pinning effect is found to be responsible for this interesting behavior and the variation of Ead is approximately equal to the change of work function. Furthermore, this effect is independent of the twist angles in the van der Waals SGH. Our results are consistent with experimental observations in overcoming the degradation of silicene in air.

Transcriptome-Wide Analysis of Core Transcription Factors Associated with Defense Responses in Autotetraploid versus Diploid Rice under Saline Stress and Recovery.

Saline stress is a major abiotic stress that inhibits plant growth and yields worldwide. The plant transcription factor (TF) family plays an important role in converting abiotic stress signals into gene expression changes. In this study, a transcriptome-based comparative analysis was performed to investigate the global gene expression of all the TFs in diploid and autotetraploid rice during the early stage of NaCl stress and recovery period. The phenotypic data indicated that the tetraploid rice exhibited a superior salt-tolerant ability compared to the diploid rice. A total of 55 TF families were co-expressed in the tetraploid and diploid rice, and the cumulative number of TF-expressed genes was relatively higher in the diploid rice than in the tetraploid rice at all time points. Unlike the diploid rice, the overall gene expression levels of the tetraploid rice were comparable to the control during recovery. The number of differentially expressed TFs (DE-TFs) in the tetraploid rice decreased after recovery, whereas it increased to a large extent in the diploid rice. GO and KEGG pathway enrichment analysis of the DE-TFs discovered the early switching of the ABA-activated signaling pathway and specific circadian rhythm in the tetraploid rice. Combining the PPI network and heatmap analysis, some core DE-TFs were found that may have potential roles to play in tetraploid salt tolerance. This study will pave the way for elucidating the complex network regulatory mechanisms of salt tolerance in tetraploid rice.

A toxin-antidote system contributes to interspecific reproductive isolation in rice.

Breakdown of reproductive isolation facilitates flow of useful trait genes into crop plants from their wild relatives. Hybrid sterility, a major form of reproductive isolation exists between cultivated rice (Oryza sativa) and wild rice (O. meridionalis, Mer). Here, we report the cloning of qHMS1, a quantitative trait locus controlling hybrid male sterility between these two species. Like qHMS7, another locus we cloned previously, qHMS1 encodes a toxin-antidote system, but differs in the encoded proteins, their evolutionary origin, and action time point during pollen development. In plants heterozygous at qHMS1, ~ 50% of pollens carrying qHMS1-D (an allele from cultivated rice) are selectively killed. In plants heterozygous at both qHMS1 and qHMS7, ~ 75% pollens without co-presence of qHMS1-Mer and qHMS7-D are selectively killed, indicating that the antidotes function in a toxin-dependent manner. Our results indicate that different toxin-antidote systems provide stacked reproductive isolation for maintaining species identity and shed light on breakdown of hybrid male sterility.

The Assessment of TLR1 Gene Polymorphism Association with the Risk of Allergic Rhinitis in the Chinese Han Population from Northern China.

Background: Environmental factors and genetic predisposition can influence the occurrence and development of AR. Toll-like receptor 1 (TLR1) belongs to the TLR receptor family, which plays a fundamental role in the activation of innate immunity. This study aimed to explore the association between TLR1 genetic loci and AR susceptibility in the Han Chinese from northern China. Methods: Genotyping of three SNPs in the TLR1 has proceeded using the Agena MassARRAY platform. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the correlation between candidate SNPs and AR susceptibility. Using FPRP (false-positive report probability analysis) to detect whether the positive results are noteworthy findings. The SNP-SNP interactions were detected by multifactor dimensionality reduction (MDR). Results: TLR1-rs72493538 (Allele "G": OR=0.77, p = 0.034) and -rs76600635 (Allele "G": OR=0.75, p = 0.024) were associated with reducing the risk of AR among Han Chinese in northern China. In addition, we found evidence that TLR1-rs72493538 (males, participants with aging > 43 years, or coming from the wind-blown sand region) and -rs76600635 (males, participants with BMI ≤ 24 kg/m2, or coming from the wind-blown sand region) were associated with AR risk in stratified analyses. FPRP showed that all positive results are noteworthy findings. MDR analysis showed that a two-loci genetic model composed of rs72493538 and rs76600635 can be chosen as the best genetic model to predict the risk of AR. Conclusion: TLR1-rs72493538 and -rs76600635 have a close association with reducing the risk of AR.

Machine learning-aided band gap prediction of semiconductors with low concentration doping.

The important physical quantities of materials, such as band gap, have been predicted efficiently with the help of machine learning (ML), in addition to the widely used experimental or computational methods. Under this scheme, by combining density functional theory (DFT) calculations and ML predictive models, the band gaps of doped semiconductors with normal doping concentrations are predicted successfully. Our present work provides a solution to the problem of how to obtain the band gaps of semiconductors doped with extremely low concentrations, which are important cases for some device designs. The structures were constructed by configuration screening with a symmetric criterion, and three-dimensional spatial structural variation was mapped to one-dimensional features, which are the key steps for the ML predictive model. The biggest error in the predicted band gaps of dilute nitride-doped GaAs by ML models is not more than 10%, compared with values obtained from DFT. Considering the limitation of material data, a few-shot learning method was further adopted to check the performance of the predictive models. The performance of the ML models was validated using data out of training and testing datasets. Our method will efficiently accelerate the prediction of physical properties of semiconductors with extremely low-concentration doping.

Generation of Vgll4-DreER transgenic mouse for visualizing and manipulating VGLL4-expressing cells in vivo.

Vestigial like family member 4 (VGLL4), a member of the Hippo pathway, is a transcriptional cofactor involved in many biological processes, such as tumor progression, postnatal heart growth, and muscle regeneration. However, the VGLL4 expression pattern in vivo remains unclear. To detect and trace Vgll4-expressing cells and their progeny, we generated and characterized a new tamoxifen-inducible Dre knock-in mouse line, Vgll4-DreER. This mouse line expressed DreER (Dre recombinase fused to the estrogen receptor) under the control of the endogenous Vgll4 promoter. After crossing the Vgll4-DreER mouse line with the Dre-responsive reporter H11-rRFP, Dre-mediated recombination in the tissue was monitored on the basis of red fluorescent protein (RFP) signals, which indicated the distribution of VGLL4-positive cells in vivo. Our data revealed that VGLL4 is widely expressed in various cell types at embryonic and neonatal stages. After comparison with our previously reported Vgll4-GFP mouse, we found that the RFP signal profile was wider than the green fluorescent protein (GFP) pattern, indicating that Vgll4-DreER is more sensitive for labeling VGLL4-expressing cells. We next used a dual-recombination system to simultaneously label VGLL4- and keratin 5 (KRT5)-positive cell populations, and no crosstalk was observed in the Krt5-CreER;Vgll4-DreER;R26-rGlR mice. Taken together, the Vgll4-DreER mouse line is a valuable new tool for examining the precise VGLL4 expression profile and conditional manipulating of VGLL4-expressing cells and their progeny.

Machine-learning-assisted discovery of boron-doped graphene with high work function as an anode material for Li/Na/K-ion batteries.

Work function (WF) modulation is a crucial descriptor for carbon-based electrodes in optoelectronic, catalytic, and energy storage applications. Boron-doped graphene is envisioned as a highly promising anode material for alkali metal-ion batteries (MIBs). However, due to the large structural space concerning various doping concentrations, the lack of both datasets and effective methods hinders the discovery of boron-doped graphene with a high WF that generally leads to strong adsorption. Herein, we propose a machine-learning-assisted approach to discover the target, where a Crystal Graph Convolutional Neural Network was developed to efficiently predict the WF for all possible configurations. As a result, the B5C27 structure is found to have the highest WF in the entire space containing 566 211 structures. In addition, it is revealed that the adsorption energy of alkali metals is linearly related to the WF of the substrate. Therefore, the screened B5C27 is investigated as an anode for Li/Na/K-ion batteries, and it possesses a higher theoretical specific capacity of 2262/2546/1131 mA h g-1 for Li/Na/K-ion batteries compared with that of pristine graphene and other boron-doped graphene. Our work provides an effective way to locate possible high-WF structures in heteroatom-doped systems, which may accelerate future screening of promising adsorbents for alkali metals.

Association between polymorphisms of the GSDMB gene and allergic rhinitis risk in the Chinese population: a case-control study.

BACKGROUND: Allergic rhinitis (AR) is a great risk factor for developing asthma, and its pathogenesis is affected by various factors, such as gene and environment. GSDMB is related to allergic diseases. Our purpose is to explore the correlation of single nucleotide polymorphisms (SNPs) in GSDMB and AR risk in the Chinese population. METHODS: We performed a case-control study including 1005 cases and 1004 controls. Rs2305479, rs4795400, and rs12450091 in GSDMB were geneotyped using Agena MassARRAY. The relationships between GSDMB SNPs and AR risk were assessed by logistic regression analysis in PLINK1.9. RESULTS: Our study showed that rs4795400 was a protective factor for AR in overall (TT vs. CC: OR = 0.66, p = 0.009; TT vs. CC/TC: OR = 0.67, p = 0.008; additive: OR = 0.87, p = 0.042 males, people with BMI ≤ 24, and living in wind-blown sand area. Rs2305479 was associated with a reduced AR risk in males (TT vs. CC: OR = 0.47, p = 0.014; TT vs. CC/TC: OR = 0.43, p = 0.004). However, rs12450091 was a risk factor for AR in people living in the loess hilly region (CC: OR = 4.75, p = 0.047). The levels of EO and EO_per in the case group were significantly higher than those in the control group (p < 0.05). CONCLUSION: This study indicated that GSDMB polymorphisms (rs4795400, rs2305479, and rs12450091) were associated with AR susceptibility. Further studies are required to confirm our findings and to clarify the functional relationship.

Selection and Validation of 48 KASP Markers for Variety Identification and Breeding Guidance in Conventional and Hybrid Rice (Oryza sativa L.).

BACKGROUND: Breeding of conventional and hybrid rice (Oryza sativa L.) have solved hunger problems and increased farmers' income in the world. Molecular markers have been widely used in marker-assisted breeding and identification of larger numbers of different bred varieties in the past decades. The recently developed SNP markers are applied for more stable and detectable compared with other markers. But the cost of genotyping lots SNPs is high. So, it is essential to select less representative SNPs and inexpensive detecting methods to lower the cost and accelerate variety identification and breeding process. KASP (Kompetitive Allele-Specific PCR) is a flexible method to detect the SNPs, and large number of KASP markers have been widely used in variety identification and breeding. However, the ability of less KASP markers on massive variety identification and breeding remains unknown. RESULTS: Here, 48 KASP markers were selected from 378 markers to classify and analyze 518 varieties including conventional and hybrid rice. Through analyzing the population structure, the 48 markers could almost represent the 378 markers. In terms of variety identification, the 48 KASP markers had a 100% discrimination rate in 53 conventional indica varieties and 193 hybrid varieties, while they could distinguish 89.1% conventional japonica rice from different breeding institutes. Two more markers added would increase the ratio from 68.38 to 77.94%. Additionally, the 48 markers could be used for classification of subpopulations in the bred variety. Also, 8 markers had almost completely different genotypes between japonica and indica, and 3 markers were found to be very important for japonica hybrid rice. In hybrid varieties, the heterozygosity of chromosomes 3, 6 and 11 was relatively higher than others. CONCLUSIONS: Our results showed that 48 KASP markers could be used to identify rice varieties, and the panel we tested could provide a database for breeders to identify new breeding lines. Also, the specific markers we found were useful for marker-assisted breeding in rice, including conventional and hybrid.

Band Structure Engineering and Defect Passivation of Cu x Ag1-x InS2/ZnS Quantum Dots to Enhance Photoelectrochemical Hydrogen Evolution.

The AgInS2 colloidal quantum dot (CQD) is a promising photoanode material with a relatively wide band gap for photoelectrochemical (PEC) solar-driven hydrogen (H2) evolution. However, the unsuitable energy band structure still forms undesired energy barriers and leads to serious charge carrier recombination with low solar to hydrogen conversion efficiency. Here, we propose to use the ZnS shell for defect passivation and Cu ion doping for band structure engineering to design and synthesize a series of Cu x Ag1-x InS2/ZnS CQDs. ZnS shell-assisted defect passivation suppresses charge carrier recombination because of the formation of the core/shell heterojunction interface, enhancing the performance of PEC devices with better charge separation and stability. More importantly, the tunable Cu doping concentration in AgInS2 CQDs leads to the shift of the quantum dot band alignment, which greatly promotes the interfacial charge separation and transfer. As a result, Cu x Ag1-x InS2/ZnS CQD photoanodes for PEC cells exhibit an enhanced photocurrent of 5.8 mA cm-2 at 0.8 V versus the RHE, showing excellent photoelectrocatalytic activity for H2 production with greater chemical-/photostability.

Substandard starch grain4 may function in amyloplast development by influencing starch and lipid metabolism in rice endosperm.

The amyloplast is a specialized plastid in rice endosperm cells where starch is synthesized and stored as starch granules (SGs). However, little is known about the molecular mechanism underlying amyloplast and SG development. In this study, a novel mutant (c134) demonstrating a floury endosperm with enlarged SGs and amyloplasts was identified. The floury endosperm was caused by rounder, loosely packed SG. Grain-quality profile and expression analysis showed reduced contents of total starch and amylose in the c134 mutant, as well as reduced expression of a number of genes involved in starch biosynthesis. Galactosyldiacylglycerol (GDG) content and fatty acid synthesis play important roles in plastid development, and in the c134 endosperm, an obvious decrease in GDG and various fatty acids was observed, with down-regulated expression of various genes involved in lipid biosynthesis. Furthermore, map-based cloning revealed an amino acid substitution (glycine to aspartic acid) in the substandard starch grain4 (SSG4) protein. The results of this study suggest that SSG4 influences the regulation of starch and lipid metabolism as well as amyloplast development, a finding that is useful for potential genetic improvement of rice grain quality in future starch and lipid breeding and biotechnology.

Prevalence of dyslipidemia and associated risk factors among adult residents of Shenmu City, China.

OBJECTIVE: Dyslipidemia is a leading risk factor for cardiovascular and cerebrovascular diseases. By collecting the blood lipid profiles among adult residents of Shenmu City in Shaanxi Province, China, we aim to assess and elucidate the prevalence and risk factors of dyslipidemia in this city. METHOD: Stratified multistage sampling was used to survey 4,598 permanent adult residents in five areas of Shenmu (2 communities in the county seat, 2 in the southern area and 2 in the northern area) from September 2019 to December 2019. Questionnaire surveys and physical examinations were conducted. Data were analyzed using SPSS software version 26.0. RESULTS: The average level of total cholesterol (TC) is 4.47mmol/L, that of triglyceride (TG) 1.32mmol/L, high-density lipoprotein cholesterol (HDL-C) 1.27mmol/L, apolipoprotein A1 (ApoA1) 1.44g/L, low-density lipoprotein cholesterol (LDL-C) 2.7mmol/L and apolipoprotein B (ApoB) 0.97g/L. The prevalence of hypercholesterolemia (HTC), hypertriglyceridemia (HTG), low high-density lipoprotein (HDL-C) and high low-density lipoprotein (LDL-C) is 22.4%, 33.3%, 14.5%, and 5.81%, respectively, and the overall prevalence of dyslipidemia is 48.27%. Furthermore, blood lipid levels and prevalence of dyslipidemia vary by region, age, gender, occupation and educational level. Nine risk factors of dyslipidemia were identified, which are living in county seat or northern industrial area, increasing age, male, overweight or obesity, abdominal obesity, smoking, hypertension, abnormal glucose metabolism (pre-diabetes or diabetes) and hyperuricemia. CONCLUSION: The blood lipid levels and dyslipidemia prevalence of adults in Shenmu City are higher comparing to national averages of China. Combining risk factors of dyslipidemia, early detection and public health interventions are necessary in high-risk population for associated cardiovascular and cerebrovascular diseases prevention.

Analysis of Prevalence and Risk Factors of Adult Self-Reported Allergic Rhinitis and Asthma in Plain Lands and Hilly Areas of Shenmu City, China.

Objective: The main aim of this study was to investigate the prevalence and risk factors of adult self-reported allergic rhinitis and asthma in plain lands and hilly areas of Shenmu City in China, and analyze the differences between regions. Methods: The multi-stage stratified random sampling was applied in a cross-sectional survey of adult residents in Shenmu City, from September to December 2019. The unconditional logistic regression analysis was used to screen the influence factors of allergic rhinitis and asthma. Results: 4,706 adults participated in the survey, and 99% (4,655 in 4,706) completed the questionnaires. The prevalence of allergic rhinitis was 25.4%, and the prevalence of asthma was 9.4%. The prevalence of the allergic rhinitis without asthma, asthma without allergic rhinitis, and the combined allergic rhinitis with asthma were 18.9, 2.9, and 6.5%, respectively. The prevalence of allergic rhinitis and asthma existed regional differences. The prevalence of adult self-reported allergic rhinitis was 41.5% in plain lands areas and 22.1% in hilly areas. The prevalence of adult self-reported asthma was 12.8% in plain lands and 8.8% in hilly areas. The prevalence of allergic rhinitis and asthma existed seasonal differences, with the highest prevalence from July to September. The analysis of risk factors showed that higher education [middle and high school (OR 1.72, 95%CI 1.42-2.07); college and above (OR 2.67, 95%CI 1.99-3.59)], comorbidities of other allergic diseases (OR 3.90, 95%CI 3.23-4.70), family history of allergies (OR 2.89, 95%CI 2.36-3.53), and plain lands areas (OR 2.51, 95%CI 2.06-3.05) were the risk factors for the allergic rhinitis without asthma. Aging [40-49 years old (OR 4.29, 95%CI 1.02-18.13); 50-59 years old (OR 5.89, 95%CI 1.40-24.76); ≥60 years old: (OR 6.14, 95%CI 1.41-26.71)], never-smokers (OR 1.66, 95%CI 0.99-2.80), comorbidities of other allergic disorders (OR 2.17, 95%CI 1.42-3.32), and family history of allergies (OR 2.20, 95%CI 1.40-3.47) were the risk factors for the asthma without allergic rhinitis. Advanced age [30-39 years (OR 2.16, 95%CI 1.23-3.82); 40-49 years (OR 2.86, 95%CI 1.56 to 5.25); 50-59 years (OR 2.95, 95%CI 1.58-5.51); ≥60 years old (OR 2.27, 95%CI 1.09-4.72)], higher education [middle and high school (OR 2.23, 95%CI 1.62-3.07); college and above (OR 4.28, 95%CI 2.72-6.74)], non-agricultural workers (OR 1.70, 95%CI 1.18-2.43),never-smokers (OR 2.26, 95%CI 1.51-3.39), comorbidities of other allergic diseases (OR 4.45, 95%CI 3.37-5.88), family history of allergies (OR 5.27, 95%CI 3.98-6.97), and plain lands areas (OR 2.07, 95%CI 1.51-2.86) were the risk factors for the combined allergic rhinitis with asthma. Conclusions: The prevalence of allergic rhinitis and asthma in Shenmu City was relatively high, with regional differences. Genetic and environmental factors were the important risk factors associated with allergic rhinitis and asthma. Our research would provide data support for preventing and controlling allergic rhinitis and asthma in this region in the future, and appropriate prevention and control programs should be formulated according to the characteristics of different regions.

[Wound-healing acceleration of mice skin by Sipunculus nudus extract and its mechanism].

In order to explore the effect of Sipunculus nudus extract (SNE) on skin wound healing in mice and its mechanism, hemostasis effect of SNE was measured, the mouse skin wound model was established by full-thickness excision. The morphological changes of the wound were observed after the treatment with SNE and the healing rate was measured. The changes of wound histology were observed by hematoxylin eosin (HE) staining, Masson staining and transmission electron microscope (TEM). The expression of cell factors and related proteins was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Results showed that the SNE possessed hemostatic function. SNE could obviously improve the healing rate of wound in mouse and shorten time of scab removal compared with the none-treatment (NT) group ( P < 0.05).The pathological histology analysis results showed complete epidermal regeneration, with remarkable capillary and collagen fiber observed in the SNE group. The expression level of tumor necrosis factor-α (TNF -α), interleukin-1ß (IL-1ß) and transforming growth factor-ß1 (TGF-ß1) in SNE group was significantly lower than that of the NT group on 7 d ( P < 0.05). Moreover, compared with the NT group, the gene expressions level of Smad7 was significantly increased and the level of type II TGF-ß receptors (TGF-ßRII), collagen I (COL1A1) and α-smooth muscle actin (α-SMA) were significantly reduced in the SNE group on 28 d ( P < 0.05), but the difference was not statistically significant compared to Yunnanbaiyao group (PC group) ( P > 0.05). These results indicated that SNE possessed obvious activity of accelerating wound healing and inhibiting scar formation, and its mechanism was closely related to hemostatic function, regulation of inflammatory factors, collagen deposition, collagen fiber remodeling and intervening TGF-ß/Smads signal pathway. Therefore, SNE may have promising clinical applications in skin wound repair and scar inhibition.

Recent Advances in 2D Lateral Heterostructures.

Recent developments in synthesis and nanofabrication technologies offer the tantalizing prospect of realizing various applications from two-dimensional (2D) materials. A revolutionary development is to flexibly construct many different kinds of heterostructures with a diversity of 2D materials. These 2D heterostructures play an important role in semiconductor and condensed matter physics studies and are promising candidates for new device designs in the fields of integrated circuits and quantum sciences. Theoretical and experimental studies have focused on both vertical and lateral 2D heterostructures; the lateral heterostructures are considered to be easier for planner integration and exhibit unique electronic and photoelectronic properties. In this review, we give a summary of the properties of lateral heterostructures with homogeneous junction and heterogeneous junction, where the homogeneous junctions have the same host materials and the heterogeneous junctions are combined with different materials. Afterward, we discuss the applications and experimental synthesis of lateral 2D heterostructures. Moreover, a perspective on lateral 2D heterostructures is given at the end.

Band gap reduction in van der Waals layered 2D materials via a de-charge transfer mechanism.

A thickness dependent band gap is commonly found in layered two-dimensional (2D) materials. Here, using a C3N bilayer as a prototypical model, we systematically investigated the evolution of a band gap from a single layer to a bilayer using first principles calculations and tight binding modeling. We show that in addition to the widely known effect of interlayer hopping, de-charge transfer also plays an important role in tuning the band gap. The de-charge transfer is defined with reference to the charge states of atoms in the single layer without stacking, which shifts the energy level and modifies the band gap. Together with band edge splitting induced by the interlayer hopping, the energy level shifting caused by the de-charge transfer determines the size of the band gap in bilayer C3N. Our finding, applicable to other 2D semiconductors, provides an alternative approach for realizing band gap engineering in 2D materials.

Influence of PEG Stoichiometry on Structure-Tuned Formation of Self-Assembled Submicron Nickel Particles.

Self-assembled submicron nickel particles were successfully synthesized via the one-step surfactant-assisted solvothermal method. The impact of surfactant and reducing agent stoichiometry is investigated in this manuscript. Different morphologies and structures of Ni particles, including flower-like nanoflakes, hydrangea-like structures, chain structures, sphere-like structures, and hollow structures were prepared through different processing conditions with two parameters such as temperature and time. Based on scanning electron microscopy (SEM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) and vibrating sample magnetometry (VSM), the submicron nickel particles show good saturation magnetization and excellent thermal stabilities with a possible growth mechanism for the variety of the structure-tuned formation. Importantly, the microwave absorption properties of the submicron nickel particles were studied. The lowest reflection loss of Ni-P9/T200/H15 with a thin layer thickness of 1.7 mm can reach -42.6 dB at 17.3 GHz.

Rice tocopherol deficiency 1 encodes a homogentisate phytyltransferase essential for tocopherol biosynthesis and plant development in rice.

KEY MESSAGE: RTD1 encodes a homogentisate phytyltransferase catalyzing a key step in rice tocopherol biosynthesis, confers cold tolerance and regulates rice development by affecting the accumulation of DELLA protein SLENDER RICE1. Tocopherols are one of the most important lipid-soluble antioxidants having indispensable roles in living organisms. The physiological functions of tocopherols have been comprehensively characterized in animals and artificial membranes. However, genetic and molecular functions of tocopherols in plants are less understood. This study aimed to isolate a tocopherol-deficient mutant rtd1 in rice. The rtd1 mutant showed overall growth retardation throughout the growth period. Most of the agronomic traits were impaired in rtd1. Map-based cloning revealed that the RTD1 gene encoded a homogentisate phytyltransferase, a key enzyme catalyzing the committed step in tocopherol biosynthesis. RTD1 was preferentially expressed in green leafy tissues, and the protein was located in chloroplasts. Cold tolerance was found to be reduced in rtd1. The cold-related C-repeat-binding factor (CBF)/dehydration-responsive element-binding protein 1 (DREB1) genes were significantly upregulated in rtd1 under natural growth conditions. Moreover, rtd1 exhibited a reduced response to gibberellin (GA).The transcript and protein levels of DELLA protein-coding gene SLENDER RICE 1 (SLR1) in rice was increased in rtd1. However, the GA content was not changed, suggesting a transcriptional, not posttranslational, regulation of SLR1. These findings implied that tocopherols play important roles in regulating rice growth and development.