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Ilex L., the exclusive genus of Aquifoliaceae, encompasses over 600 dioecious wood species with a highly irregular distribution, predominantly found in South America and Asia. The phylogeny and classification of this genus remain enigmatic due to significant early extinctions, constrained morphological diversity, recent hybridization/introgression, and conflicting signals from previously utilized markers. This study presents phylogenetic reconstructions based on complete chloroplast genome sequences and single nucleotide polymorphisms (SNPs) derived from genome resequencing data. A total of 116 accessions of Ilex, representing approximately 108 taxa, were included as the ingroup, with five accessions of two species serving as outgroups. Analysis of the chloroplast genome and nuclear SNP data individually resulted in two robust phylogenetic trees, revealing substantial discrepancies between the chloroplast genome and nuclear SNP phylogenies at both the species and clade levels. The chloroplast genome sequences successfully resolved relationships within this genus into eight strongly supported major clades, while the nuclear SNPs resolved relationships into seven highly supported major clades. Our nuclear SNP phylogenetic tree, in comparison to the chloroplast genome tree, aligns more closely with the recently updated classification of Ilex in multiple instances. The extensive cytonuclear discordance identified may be attributed to recent hybridization events and incomplete lineage sorting (ILS)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the 'floristic geo-lithology hypothesis', which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions., (© 2024. The Author(s).)

Sedumjinglanii , a new species of Crassulaceae from Mount Danxia in Guangdong, China, is described and illustrated. Phylogenetic analysis based on the internal transcribed spacer (ITS) region of nr DNA suggests that the new species belongs to S.sect.Sedum sensu Fu and Ohba (2001) in the "Flora of China", and is sister to a clade comprising S.alfredi and S.emarginatum with high support values (SH-aLRT = 84, UFBS = 95) but is distantly related to S.baileyi . The new species is morphologically similar to S.alfredi but it can be distinguished from the latter in its opposite leaves (vs. alternate leaves), its usually wider leaves (0.4-1.2 cm vs. 0.2-0.6 cm), its usually shorter petals (3.4-4.5 mm vs. 4-6 mm), its shorter nectar scales (0.4-0.5 mm vs. 0.5-1 mm), its shorter carpels (1.5-2.6 mm vs. 4-5 mm), and its shorter styles (0.6-0.9 mm vs. 1-2 mm). The new species can be easily distinguished from S.emarginatum which both have opposite leaves by its short, erect or ascending rhizome (vs. long and prostrate rhizome in the latter), shorter petals (3.4-4.5 mm vs. 6-8 mm) and shorter carpels (1.5-2.6 mm vs. 4-5 mm). It can also be easily distinguished from S.baileyi by its short, erect or ascending rhizome (vs. long and prostrate rhizome) and its shorter style (0.6-0.9 mm vs. 1-1.5 mm)., (Yan-Shuang Huang, Kai-Kai Meng, Yuan-Yuan Sun, Zai-Xiong Chen, Qiang Fan.)

The new species Eriobotryacrassifolia , collected from Yunnan Province, China, is characterised and illustrated. A phylogeny based on chloroplast genomes supported its closest affinity with E.tengyuehensis , while a phylogeny based on 197 single-copy nuclear genes supported its closest affinity with E.fragrans and E.deflexa . Morphologically, however, it resembles E.angustissima . Nevertheless, it can be easily distinguished from E.angustissima by its abaxially retroflexed and sharply serrate leaf margins, densely rusty tomentose inflorescences, and oblong or elliptic leaves., (Kai-Kai Meng, Su-Fang Chen, Min Lin, Wen-Bo Liao, Jian-Hua Jin, Qiang Fan.)

As a consequence of hybridization, polyploidization, and apomixis, the genus Cotoneaster (Rosaceae) represents one of the most complicated and controversial lineages in Rosaceae, with ca. 370 species which have been classified into two subgenera and several sections, and is notorious for its taxonomic difficulty. The infrageneric relationships and taxonomy of Cotoneaster have remained poorly understood. Previous studies have focused mainly on natural hybridization involving only several species, and phylogeny based on very limited markers. In the present study, the sequences of complete chloroplast genomes and 204 low-copy nuclear genes of 72 accessions, representing 69 species as ingroups, were used to conduct the most comprehensive phylogenetic analysis so far for Cotoneaster. Based on the sequences of complete chloroplast genomes and many nuclear genes, our analyses yield two robust phylogenetic trees respectively. Chloroplast genome and nuclear data confidently resolved relationships of this genus into two major clades which largely supported current classification based on morphological evidence. However, conflicts between the chloroplast genome and low-copy nuclear phylogenies were observed in both the species level and clade level. Cyto-nuclear discordance in the phylogeny could be caused by frequent hybridization events and incomplete sorting lineage (ILS). In addition, our divergence-time analysis revealed an evolutionary radiation of the genus from late Miocene to date., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Eriobotrya laoshanica , a new species of Rosaceae from Yunnan, China, is described and illustrated. The new species is easily distinguished from the most similar species E. malipoensis K. C. Kuan by its longer petioles (2-5 vs. 0.5-1 cm); indumentum on the lower leaf surfaces (densely tomentose vs. glabrous); much fewer flowers (15- to 30-flowered vs. 50- to 100-flowered) on the panicle; larger flowers (2.5-3 vs. 1.5-2 cm in diameter); and non-angulated (vs. angulated) young fruits., (Su-Fang Chen, Kai-Kai Meng, Xi-Bing Guo, Wan-Yi Zhao, Wen-Bo Liao, Qiang Fan.)

Saxifraga damingshanensis (Saxifragaceae), a new species from Damingshan Nature Reserve in Guangxi Province, is described and illustrated. A morphological comparison between the new species and its putative relatives, S. mengtzeana and S. luoxiaoensis , is presented. The new species is morphologically similar to S. mengtzeana , but it can be easily distinguished by its non-peltate leaf, both surfaces of mature leaf blade covered with white glandular trichome, petals 3-veined and margin entire. Phylogenetic analysis, based on two chloroplast DNA regions ( matK and psbA-trnH ), confirmed that the new species belongs to S. sect. Irregulares. The new species is currently only known from Damingshan, Guangxi and we assign it an IUCN Red List preliminary status as Data Deficient., (Wan-Yi Zhao, Kai-Kai Meng, Qiang Fan, Jian-Hua Jin, Wen-Bo Liao.)

Spin-wave dynamics in full-Heusler Co 2 Fe 1-x Mn x Al films have been investigated using all-optical pump-probe magneto-optical polar Kerr spectroscopy. We find magnetic damping and anisotropy can be modulated by composition x. Damon-Eshbach (DE) spin wave occurs only in the samples which present intrinsic magnetic damping and have huge uniaxial magnetic anisotropy, implying that intrinsic magnetic damping and huge uniaxial magnetic anisotropy is the necessary conditions to excite coherent DE spin wave. Kittel spin wave appears in low uniaxial magnetic anisotropic samples and presents extrinsic magnetic damping. Therefore, laser-excited spin-wave modes can be manipulated by magnetic anisotropy, whose physical picture is discussed phenomenologically.

Multiferroic hybrid structures PbZr 0.2 Ti 0.8 O 3 (PZT)/La 0.7 Sr 0.3 MnO 3 (LSMO) and PZT/MgO/LSMO were epitaxially deposited on (001) Nb:SrTiO 3 crystals. Crystallinity and ferroelectric domain structures were investigated for the PZT/LSMO heterostructure. Interestingly, relatively high non-volatile magnetoelectric coupling effects were observed in both heterostructures at room temperature. The change of chemical valence for Mn and Ti at the PZT/MgO/LSMO interface may play a dominant role rather than external strain or orbital reconstruction, which lead to a large modulation of the magnetization. Correspondingly, the transport behavior of the PZT/MgO/LSMO heterostructure is investigated to confirm the role of oxygen vacancies motion. Our result indicates that the PZT/MgO/LSMO heterostructure have a promising application for future high-density non-volatile memories.

The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

The magnetic properties of a Co2FeAl/(Ga,Mn)As bilayer epitaxied on GaAs (001) are studied both experimentally and theoretically. Unlike the common antiferromagnetic interfacial interaction existing in most ferromagnet-magnetic semiconductor bilayers, a ferromagnetic interfacial interaction in the Co2FeAl/(Ga,Mn)As bilayer is observed from measurements of magnetic hysteresis and x-ray magnetic circular dichroism. The Mn ions in a 1.36 nm thick (Ga,Mn)As layer remain spin polarized up to 400 K due to the magnetic proximity effect. The minor loops of the Co2FeAl/(Ga,Mn)As bilayer shift with a small ferromagnetic interaction field of +24 Oe and -23 Oe at 15 K. The observed ferromagnetic interfacial coupling is supported by ab initio density functional calculations. These findings may provide a viable pathway for designing room-temperature semiconductor spintronic devices through magnetic proximity effect.