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In view of the changes in the form of low-voltage distribution networks caused by the access of large-scale distributed generation （DG） and DC loads in the new power system， the protection and control of the distribution network under the new situation is studied. Firstly， this paper establishes a typical topology structure of a new distribution network with distributed generation and DC loads， and studies the transient characteristics on AC side and DC side， as well as the transient impedance characteristics during faults. Secondly， a new protection and configuration method and protection setting principle for low-voltage distribution networks under a new pattern is constructed based on transient characteristics. Finally， a new distribution network model is built using the MATLAB simulation platform to simulate the faults at typical locations of AC/DC distribution networks. It is verified that the proposed protection and control method has the advantages of accurate judgment and easy implementation.

Carpesium (Family – Compositae) is a genus with 24 species of mainly perennial herbs. Several species of this genus have served as folk medicine in China and Korea for their antipyretic, anti-inflammatory, analgesic, antifungal, antibacterial, and cytotoxic activity properties. Chemical constituents are mostly sesquiterpenes, diterpenes, glycosides, and several other types of compounds. This article summarizes the literature on the isolated and identified constituents from various Carpesium species and their various biological activities.

Achieving high-performance circularly polarized organic room temperature phosphorescence (CPRTP) holds significant academic and industrial importance. Herein, a series of near-infrared, color-tunable, and long-lived CPRTP materials have been successfully constructed by doping achiral luminescent guests into chiral crystallizable hosts. Naphthalimide derivatives are chosen as the guest molecules owing to the large conjugation and good structure tunability. (−)-Di-p-toluoyl- L - and (+)-di-p-toluoyl- D -tartaric acid are selected as the host molecules on account of the outstanding chirality and crystallinity. Through doping naphthalimide into tartaric acid derivatives, the resultant materials show the desirable CPRTP with a luminescence dissymmetry factor equal to 1.14 × 10−2. The host stabilizes and protects triplet excitons generated from the guest and induces the chirality of phosphorescence. Impressively, the doping material is emissive in the near-infrared region of 720 nm, which has hardly been achieved before. By modifying the chemical structure of the guest, the phosphorescent color of doping materials can be well-modulated from green to yellow and red. Moreover, the doping material displays a lifetime of up to 2.14 s. It is highly anticipated that this work will provide a new design strategy for high-performance CPRTP materials. [ABSTRACT FROM AUTHOR]

Simple Summary: The BMPR1B and T/Brachyury genes are considered major genetic factors influencing sheep reproduction and tail bone number. In this study, we conducted an association analysis between nine mutations of the BMPR1B gene and the litter sizes of short-tailed Gobi sheep and larger-tailed Ujimqin sheep. We also compared the frequency of the favorable alleles of four mutations among Gobi short tail sheep, Ujimqin sheep, and Mongolia sheep. In addition, we confirmed that the frequency of tail-bone-number-related T alleles at position c.363G>T in the T gene was significantly higher in short-tailed Gobi sheep than larger-tailed Ujimqin sheep. The significant deposition of tail fat in sheep has a profound impact on the economic benefits of animal husbandry. Furthermore, increasing the litter size is a crucial means of enhancing economic benefits. The BMPR1B and T/Brachyury genes are considered major functional genes that could affect sheep litter size and tail bone number, respectively. In this study, we employed direct sequencing to identify specific mutations of the BMPR1B gene in Gobi short tail sheep and carried out genotyping using MassARRAY technology for each variant of both the BMPR1B and T genes. Significant associations were demonstrated between the c.687G>A mutation of BMPR1B and the litter size in both the Gobi short tail sheep and Ujimqin sheep breeds. Meanwhile, the g.30058882_30058873GCAGATTAAAIndel mutation was significantly associated with the litter size in Gobi short tail sheep. These findings may provide valuable genetic markers for expanding sheep litter size. In addition, we also confirmed that the frequency of tail-bone-number-related T alleles was significantly higher in Gobi short tail sheep than in longer-tailed Ujimqin sheep. [ABSTRACT FROM AUTHOR]

Constant stiffness confining condition seems more reasonable than constant stress confining condition to simulate the actual confining stress environment of in situ rock which varies with the lateral strain. Compression tests of sandstone samples with two different confining conditions were conducted to study the energy evolution characteristics of rock under constant stress confining condition and constant stiffness confining condition. Except for the conventional triaxial compression tests, CFRP-confined rock samples were also used to simulate the constant stiffness confinement of the rock specimen in the laboratory. The stress–strain curve and failure mode of the samples under different confining conditions were compared. The influence of confining condition on the characteristics of rock energy evolution was investigated. The results show that the stress–strain curves under the confining conditions of constant stress and constant stiffness exhibited strain softening and strain hardening, respectively. Under constant stress confining condition, the specimen failed in the ductile mode while the specimen exhibited a sudden and brittle failure behavior under constant stiffness confining condition. The evolution trend of the elastic strain energy was greatly affected by the magnitude of confining stiffness. The elastic strain energy of the specimen under low stiffness confining condition decreased slightly after reaching its peak. As the confining stiffness increased, the elastic strain energy would not decrease but continued to increase until the failure of the specimen. The maximum elastic strain energy under the confining condition of the high confining stiffness is greater than that of constant stress. Considering the influence of confining stiffness on the storage and release of the strain energy, to obtain the true mechanical behavior of the rock mass under confining conditions, stiffness confining conditions should be taken into consideration in the laboratory.