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Patients with skeletal Class Ⅱ often show symptoms such as protrusion of maxillary anterior teeth, mandibular retraction, open lips and teeth, deep overbite, and deep overjet, which seriously affect the facial appearance. This article reports a case of an adolescent male patient with skeletal Class Ⅱ combined with impacted teeth treated by one-stage early correction and two-stage fixation. After treatment, the patient’s skeletal Class Ⅱ symptoms improved significantly, including the improvement of mandibular retraction. The problem of open lips and teeth was solved; the facial appearance tended to be straight, and there was no obvious abnormality of the temporomandibular joint. This case shows that early correction can achieve good therapeutic effects on this kind of patients and can avoid or reduce the possibility of orthognathic surgery for these patients in adulthood.

Propargylic alcohols are regarded as a class of readily available and versatile synthons in organic synthesis. Due to their unique bifunctional character, the transformation of propargylic alcohols has been widely utilized as a powerful strategy for the construction of various functionalized frameworks over the past few decades. Recently, the radical transformation of propargylic alcohols has attracted considerable attention in synthetic chemistry. This review summarizes recent progress in the radical transformation of propargylic alcohols. Based on the different mechanisms of radical formation underlying these transformations, this review has been divided into four parts: (1) transition‐metal catalyzed radical transformation; (2) photo‐induced radical transformation; (3) electro‐induced radical transformation; and (4) metal‐free or oxidant‐mediated radical transformation of propargylic alcohols. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of this study was to explore the genetic resources of the Huitang duck (HT) in Hunan Province, China, and investigate its population structure and genetic potential through comparative analysis with various duck populations. The results showed that HT belonged to the versatile duck breed, exhibiting significant phenotypic and genetic differences compared to other duck breeds in Hunan Province. The inspection of genomic selective signals in their genome showed that selected candidate genes were involved in the growth and development of skeletal muscle and ovary. These findings provide valuable information for future breeding programs and genetic preservation of HT. The Huitang duck (HT), a long-domesticated elite local breed from Hunan Province, China, with excellent meat quality, has not had its population genetic structure and genomic selective sweeps extensively studied to date. This study measured the phenotypic characteristics of HT and conducted comparative analysis between HT and 16 different duck breeds, including wild, indigenous, and meat breeds, to characterize its population structure and genetic potential. The results revealed that HT is a dual-purpose indigenous breed with a genetic background closely related to the Youxian sheldrake and Linwu ducks. In the selective sweep analysis between HT and Linwu ducks, genes such as PLCG2, FN1, and IGF2BP2, which are associated with muscle growth and development, were identified near the 27 selection signals. The comparison between HT and Jinding ducks revealed 68 selective signals that contained important genes associated with ovarian development (GRIK4, MAP3K8, and TGIF1) and egg-laying behaviors (ERBB4). Selective sweep analysis between HT and Youxian sheldrake ducks found 93 selective regions covering genes related to both meat (IGF1R and IGFBP5) and egg-production (FOXO3 and ITPR1) traits. Our study may provide novel knowledge for exploring the population structure and genetic potential of HT, offering a theoretical basis for its breeding strategies in the future. [ABSTRACT FROM AUTHOR]

The investigation of micropore structure changes by H2O2-coal reactions can provide an understanding of macroscopic effects of oxidant stimulation on coalbed methane (CBM) diffusion and seepage behavior. In this study, we prepared H2O2 to oxidize coals with three different ranks, and scanning electron microscopy (SEM), high-pressure mercury intrusion (HPMI), low-temperature N2 adsorption (LT-N2A), low field nuclear magnetic resonance (LF-NMR) tests were conducted to characterize variations in micropore structures of the coals treated with H2O2. The results showed that H2O2 treatment can change, to varying degrees, the pore structure characteristics of coals with different rank. The SEM results showed that coal surface structures were destroyed by oxidation and dissolution, and pores and fissures became more developed after H2O2 treatment. The HPMI and LT-N2A tests revealed that the porosity, total pore volume, maximum pore throat diameter and average pore diameter of coals with different rank generally increased after H2O2 treatment. The HPMI-derived fractal dimensions of seepage pores decreased after oxidation, indicating that the heterogeneity of pore structure was weakened and the connectivity was improved. The fractal dimensions of adsorption pores derived from LT-N2A generally showed a downward trend, indicating that oxidation can reduce the roughness and complexity of adsorption pores, and improve the pore connectivity. The results of LF-NMR tests also corroborated the above findings. The mechanism of coal permeability enhancement by H2O2 treatment is reflected mainly in the oxidation and dissolution of organics and inorganic minerals. Thus, H2O2 treatment can lead to more significant oxidation effects on low- and medium-rank coals. This study suggests that H2O2 can be used for fracturing addition fluid in low- to medium-rank coals to improve coal permeability, thereby remove plugging and enhancing CBM recovery effectively. [ABSTRACT FROM AUTHOR]