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Dendrobium is the second largest genus of Orchidaceae, distributed in southern and southwestern China. The number of Dendrobium is large, but some taxa have not been discovered. During the investigation of orchid resources in Xizang, two Dendrobium species were discovered, which were identified as D. macraei Lindl. and D. ritaeanum King & Pantl. Both were recorded for the first time in China. The results are as follows: D. macraei is similar to D. plicatile, with the difference that the edge of the middle lobe of lip is entire, apex concave; D. ritaeanum is similar to D. angustifolium, the flowers of the former are very small, and sepals and petals do not have purple stripes, and the lip is triangular up to 1.4 cm in length. The detailed morphological characteristics and photographs of the two species are provided. The specimens are stored in the Herbarium of Xizang Agricultural and Animal Husbandry University. This discovery enriches the local data and the potential medicinal plant resource reserve of orchids in China, and is of great significance to the biodiversity study of orchids and the investigation of medicinal orchid resources.

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a global threat to wheat production. Aegilops tauschii, one of the wheat progenitors, carries the YrAS2388 locus for resistance to Pst on chromosome 4DS. We reveal that YrAS2388 encodes a typical nucleotide oligomerization domain-like receptor (NLR). The Pst-resistant allele YrAS2388R has duplicated 3' untranslated regions and is characterized by alternative splicing in the nucleotide-binding domain. Mutation of the YrAS2388R allele disrupts its resistance to Pst in synthetic hexaploid wheat; transgenic plants with YrAS2388R show resistance to eleven Pst races in common wheat and one race of P. striiformis f. sp. hordei in barley. The YrAS2388R allele occurs only in Ae. tauschii and the Ae. tauschii-derived synthetic wheat; it is absent in 100% (n = 461) of common wheat lines tested. The cloning of YrAS2388R will facilitate breeding for stripe rust resistance in wheat and other Triticeae species.

Compared to traditional tunnel construction, artificial freezing involves two distinct stages: freezing and thawing. However, this process can pose a risk to the surrounding environment if it is not possible to accurately analyze the frost heave and thawing settlement during the freezing process. The thermomechanical coupled mathematical model of formation frost heave was established by considering boundary conditions, such as formation temperature and convective heat transfer, and introducing the parameters of instantaneous volumetric strain and denaturation characteristic coefficient. In addition, the numerical analysis method for the whole construction process of the tunnel by the horizontal freezing method was established by programming the user subroutine that takes into account the characteristic coefficients of frozen soil relying on the secondary development technology of ABAQUS (version 2022). Then, the method was applied to the horizontal freezing engineering of a double-line tunnel, and the distribution laws of the freezing temperature field and frost heave displacement field were obtained and compared with the field measurement results. The numerical analysis method for determining the deformation law of the ground surface has been shown to be reliable through comparison with field measurements. This method can serve as a reference for designing effective ground surface heaving control schemes during the freezing construction period of tunnels in complex environments. [ABSTRACT FROM AUTHOR]

Metal-trihalide perovskite quantum dots combine the unique semiconducting properties of bulk perovskites with the controllable exciton dynamics benefiting from the quantum confinement effect. Composition- and size-adjustable electronic and optical properties of perovskites convert into a variety of applications. Here, we start from a brief introduction to perovskite quantum dots, followed by a detailed description of the synthesis methods and surface modification/passivation strategies of these nano-sized particles. Then, we review the applications of perovskite quantum dots including light-emitting diodes, photovoltaics, catalysis, sensing, bioimaging, and lasers. Finally, we develop outlooks for promising futures toward the commercial application of perovskite quantum dots. [ABSTRACT FROM AUTHOR]