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As a two-dimensional crystal, molybdenum trioxides (α-MoO 3) has been considered as a typical candidate for next-generation photodetectors (PDs) but with limited photodetection applications in the ultraviolet region. Here, a photo-induced thermoelectric (PTE) effect in α-MoO 3 is proposed as a practical approach to realize the broadband photodetection of α-MoO 3 /Si heterojunction PDs. High-quality α-MoO 3 films are grown on Si by using an e-beam evaporation method. By modulating the photo-induced thermoelectric potential along the c-axis on the transport properties, the α-MoO 3 /Si PDs can be operated as a self-powered device, showing broadband photoresponse beyond the bandgap limitation in the wavelength range of 405–1550 nm. The manipulation of the PTE effect in the heterojunction is investigated carefully, clarifying the corresponding physical mechanisms of the unique photoresponse behaviors. Furthermore, the fabricated device exhibits competitive photodetection performance with a high photoresponsivity of 63.3 mA/W, a high optical detectivity of 3.1 × 1011 cm Hz1/2W−1, fast response speeds with the rise/fall times of 0.47/0.76 ms, as well as high durability and environmental stability under 980-nm infrared illumination. These results not only provide a novel strategy to develop novel PDs with high performance, but also supply a deeply understanding of the PTE effect in α-MoO 3 /Si heterojunctions. [ABSTRACT FROM AUTHOR]

Abstract: The electrical and optical characteristics of Zn+ ion-implanted Ni/Au ohmic contacts to p-GaN were investigated. After the preparation of Ni/Au electrode on the surface of p-GaN, the metal/p-GaN contact interface was doped by 35keV Zn+ implantation with fluences of 5×1015–5×1016 cm−2. Subsequent rapid thermal annealing of the implanted samples were carried in air at 200–400°C for 5min. Obvious improvements of the electrode contact characteristics were observed, i.e. the decrease of specific contact resistance and the increase of light transmittance. The lowest specific contact resistance of 5.46×10−5 Ωcm2 was achieved by 1×1016 cm−2 Zn+ implantation. The transmission enhancement of the electrodes was found as the annealing temperature rises. Together with the morphology and structure analyses of the contacts by scanning and transmission electron microscope, the corresponding mechanism for such an improvement was discussed. [Copyright &y& Elsevier]

As climate change continues to negatively impact our farmlands, abiotic factors like salinity and drought stress increasingly threaten global food security. The development of elite germplasms with resistance to multiple abiotic stresses is essential for breeding climate-resilient wheat cultivars. In this study, we determined that the previously reported salt-tolerant st1 mutant, obtained via spaceflight mutagenesis, may also resist to drought stress at the seedling stage. Moreover, our field trial revealed that yield-related traits including plant height, 1000-grain weight, and spike number per plant were significantly increased in st1 compared to the wild type. An F 2 population of 334 individuals derived from a cross between the wild type and st1 displayed a bimodal distribution indicating that st1 plant height is controlled by a single major gene. Our Bulked Segregant Analysis and exome capture sequencing indicate that this gene is located on chromosome 4D. Further genetic linkage and gene sequence analysis suggests that a reverse mutation of Rht2 is putatively responsible for plant height variation in st1. Our genotypic and phenotypic analysis of the F 2 population and F 3 lines indicate that this reverse mutation significantly increases plant height and thousand grain weight but slightly decreases spike number per plant. Together, these results supply helpful information for the utilization of Rht2 in wheat breeding and provide an important material for breeding environmentally resilient, high-yield wheat varieties. • The st1 mutant is tolerant to drought stress at seedling stage. • Plant height, grain weight and spike number of st1 were significantly increased. • Gene mapping indicates that a reverse mutation of Rht2 enhances st1 plant height. • The mutation in Rht2 also increases grain weight but decreases spike number in st1. [ABSTRACT FROM AUTHOR]

• The metabolism of carotenoids in apricot fruit was studied by LC-MS/MS. • ε-Carotene, α-cryptoxanthin and apocarotenal were found in apricot fruit. • The diversity of carotenoid components and contents of the Central Asian variety group in Xinjiang were explored. • β-carotene and (E/Z)-phytoene are the main carotenoids in apricot fruits. • The content of carotenoids in the peel of 41 apricot fruits was higher than that in the flesh. The carotenoids in the peel and flesh of 41 apricot cultivars were qualitatively and quantitatively analysed by UHPLC-APCI-MS/MS, and the L*, a*, b* and quality indexes of the fruits were determined. The results showed that the L*, a*, b* and quality indexes of the fruits were quite different, and 13 carotenoids were detected in the peel and flesh of apricots, among which ε-carotene, α-cryptoxanthin and apocarotenal were newly detected carotenoids in apricots. The total carotenoid content of the 41 apricot cultivars varied from 20.983 to 320.278 μg/g FW, and the total carotenoid content varied from 17.353 to 222.098 μg/g FW in the peel and from 2.536 to 98.179 μg/g FW in the flesh. The main components of apricot fruits were β-carotene and (E/Z)-phytoene, followed by β-cryptoxanthin and lutein. This study shows that carotenoids in apricot fruits have rich metabolic diversity. [ABSTRACT FROM AUTHOR]

Heavy-ion beam irradiation is an effective approach for mutation breeding. Understanding the damage effects and molecular variation induced by mutagenesis is of great significance for improving mutation breeding efficiency. The molecular changes induced by 7Li-ion beam irradiation in wheat have been scarcely reported. In this study, we compared the biological damage effects of different doses of 7Li-ion beam irradiation on the M 1 seedlings of two wheat varieties with different γ irradiation sensitivities, Jing411 and Heyou1, and found that doses of 25, 50, 75 and 100 Gy significantly decreased the germination rate and seedling height. Moreover, transcriptome sequencing of three biological replicates of each irradiated sample and unirradiated control revealed that more single-nucleotide variants (SNVs) than small insertions and deletions (indels) were induced by various doses of 7Li-ion beam irradiation in both varieties. Substantially elevated frequencies of mutations relative to gene density were observed on 0–10 Mb of chromosome 1A, 80–90 Mb of chromosome 1B, 720–730 Mb of chromosome 2B, 280–290 Mb of chromosome 3B, 580–590 Mb of chromosome 3D, and 150–160 Mb of chromosome 5D, indicating that mutation hotspots existed in these regions. In addition, KEGG enrichment analysis of differentially expressed genes (DEGs) between control and irradiated wheat revealed pathways significantly enriched in both Jing411 and Heyou1, including "Phenylpropanoid biosynthesis", "Phenylalanine metabolism" and "Photosynthesis-antenna proteins". These pathways may play key roles in the response to 7Li-ion beam irradiation. The analysis of genes commonly upregulated under various doses of irradiation indicated that genes involved in antioxidant processes are active in the response to 7Li-ion beam irradiation. This transcriptome dataset provides a valuable public information platform for investigating the transcriptome sequence variation induced by 7Li-ion beam-induced mutagenesis and offers a basis for crop mutation breeding. • Two wheat varieties showed different responses to 7Li-ion beam irradiation. • More SNV than indels were induced by various doses of 7Li-ion beam irradiation. • Hotspot mutations were detected by comparing frequency of mutations and gene. • The pathways and genes in the response to 7Li-ion beam irradiation were identified. [ABSTRACT FROM AUTHOR]

• The pollen grains had three germination furrows, and the main type of pollen grain exine ornamentation was stripe ornamentation. • According to Erdtman's NPC classification system, the pear pollen was of the N 3 P 4 C5 type. • There were interspecific and variety or type differences in floral organ and pollen morphology. • There were many similarities between the 'Korla fragrant pear' and local pear varieties in Xinjiang, which should be classified within the Pyrus sinkiangensis Yü. system. The characters of floral organ and pollen of local pear varieties in Xinjiang, such as the 'Korla fragrant pear' and 39 other varieties or types, Pyrus bretschneideri Rehd., Pyrus pyrifolia Nakai., and Pyrus communis L. were measured and described. The genetic relationships between the 'Korla fragrant pear' and other local pear varieties in Xinjiang were analyzed by clustering. The number of flowers per inflorescence of varieties or types was approximately 7.6, and the difference in the number of stamens was small. Except for 'Aiwenqieke', 'Qipanli' and 'Daxiangshui', which had no pollen, the pollen quantity of the varieties or types was 1000.0–5000.0 grains. The pollen grains were isopolar and radiation symmetrical single-grain. The pollen grains had three germination furrows, and the main type of pollen grain exine ornamentation was stripe ornamentation. According to Erdtman's NPC classification system, the pear pollen was of the N 3 P 4 C 5 type. According to the clustering results, there was high similarity between the 'Korla fragrant pear' and Pyrus sinkiangensis Yü. The 'Korla fragrant pear' clustered with most local varieties in Xinjiang, and a genetic relationship between P. bretschneideri and P. pyrifolia was observed. There were interspecific and variety or type differences in floral organ and pollen morphology between P. sinkiangensis and P. bretschneideri , P. pyrifolia , Pyrus ussuriensis Maxim., P. communis and Pyrus betulifolia Bunge. There were many similarities between the 'Korla fragrant pear' and local pear varieties in Xinjiang, which should be classified within the P. sinkiangensis system. [ABSTRACT FROM AUTHOR]