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Chinese mahogany (Toona sinensis) is a woody plant that is widely cultivated in China and Malaysia. Toona sinensis is important economically, including as a nutritious food source, as material for traditional Chinese medicine and as a high‐quality hardwood. However, the absence of a reference genome has hindered in‐depth molecular and evolutionary studies of this plant. In this study, we report a high‐quality T. sinensis genome assembly, with scaffolds anchored to 28 chromosomes and a total assembled length of 596 Mb (contig N50 = 1.5 Mb and scaffold N50 = 21.5 Mb). A total of 34,345 genes were predicted in the genome after homology‐based and de novo annotation analyses. Evolutionary analysis showed that the genomes of T. sinensis and Populus trichocarpa diverged ~99.1–103.1 million years ago, and the T. sinensis genome underwent a recent genome‐wide duplication event at ~7.8 million years and one more ancient whole genome duplication event at ~71.5 million years. These results provide a high‐quality chromosome‐level reference genome for T. sinensis and confirm its evolutionary position at the genomic level. Such information will offer genomic resources to study the molecular mechanism of terpenoid biosynthesis and the formation of flavour compounds, which will further facilitate its molecular breeding. As the first chromosome‐level genome assembled in the family Meliaceae, it will provide unique insights into the evolution of members of the Meliaceae. [ABSTRACT FROM AUTHOR]

Introduction: Composite resin has been widely used as a dental restorative material among general dental practitioners (GDP), private services included. Various factors could affect the quality of an anterior composite restoration, such as composite resin material, type of light cure unit, use of rubber dam and technique applied. Objectives: To assess and identify GDPs preferences regarding different procedures in anterior composite resin restoration, as well as whether clinical experience or post-graduate training affects their preferences. Materials and methods: A validated questionnaire survey involving sociodemographic data and anterior composite resin restoration preferences was conducted among 63 GDPs from the private sector of Penang Island, Malaysia. Results and discussion: About 27% of GDPs had less than five years of clinical experience, while only 7.9% had postgraduate training. Majority (93.7%) had attended courses on composite resin restoration. The use of nanofiller type of composite, two-step etch and rinse (acid + primer/ adhesive) adhesive system, emitting diode light cure, enamel bevelling in cavity preparation and immediate polishing post-composite placement were preferred. A significant association was observed the years of clinical experience with microhybrid, microfilled and nanofilled composite material, rubber dam placement and zinc aluminium oxide polishing bur usage. Also, GDPs with postgraduate training significantly practised enamel bevelling procedure. Conclusions: There are variances of anterior composite resin restorations procedures and preferences among GDPs. Clinical experience and post-graduate training influence their preferences for anterior composite restoration procedures. [ABSTRACT FROM AUTHOR]