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Extant species of Liquidambar L. exhibit a disjunct distribution between western and eastern Asia and eastern North America to Central America, with the highest species diversity being in China. In this study, two new species of Liquidambar are described from the Eocene of Hainan Island, South China: L. hainanensis on basis of the leaf fossils, and L. ovoidea based on compressions of infructescences. The co‐occurrences of L. hainanensis leaves, associated infructescences of L. ovoidea and dispersed pantoporate pollen grains have the combination of morphological features peculiar to the genera Liquidambar and former Semiliquidambar and Altingia. This is considered further palaeobotanical justification for the placement of these three genera into a single genus, Liquidambar, proposed earlier based on molecular markers. Our data provide evidence for the occurrence of an ancestral polymorphic group of Liquidambar species (L. maomingensis with associated capitate infructescences, L. bella, L. hainanensis and L. ovoidea) during the Eocene in South China, and corroborate the view that South China could have been a centre of Liquidambar speciation during the Eocene. The morphological similarity of L. hainanensis leaves to those of the extant species L. orientalis from Western Asia and the North American L. styraciflua may support the importance of both the North Atlantic Land Bridge and the Bering Land Bridge for the dispersal of Liquidambar. Analysis of fossil species of Liquidambar from eastern Asia also contributes to further understanding of patterns in the taxonomic diversity and evolutionary history of this genus. [ABSTRACT FROM AUTHOR]

Today, it is decisive to determine educational trends for the long-term development of both states and societies. The 21st century proposed fundamentally new approaches to setting educational goals and achieving educational results. An important step towards addressing this issue was the introduction of the “21st Century Skills” concept. One of its elements is “Cultural and civic literacy”. Thus, the international community has made an effort to conduct research in the field of citizenship education. The study aims at forming a comprehensive understanding of the content and assessing the formation of civic literacy by various subjects (in this case, participants in the educational process in the city of Moscow). The selection of research methods and the development of research tools are based on the conceptual provisions in the field of functional literacy. The research novelty is associated with the adoption of innovative international methods by Moscow educational organizations. The study results can be presented in the form of three blocks: a block that determines the level of knowledge and understanding of civic literacy; a block that describes the preconditions and current formation of civic literacy in Moscow educational institutions; a block that represents the self-assessment of civic literacy among participants in the educational process. The study results prove that the respondents demonstrate a fairly high level of proficiency in basic civic terms in the field of knowledge and understanding. This fact correlates with their level of self-esteem. According to the respondents, the necessary conditions for mastering civic literacy are systematic citizenship education at school, the formation of legal culture in families, and the availability of the Internet.

Consideration is given to biometric indices and vitality structure of Oxytropis kungurensis Knjasev (Fabaceae), an endemic species of the South Urals and Central Cis-Ural Region, observed in 2015 and 2016 in the coenopopulation on the eastern shore of Lake Aushkul (Uchalinsky District, Republic of Bashkortostan, Russia). The paper reveals differences in plant biometrics and vitality according to the years of observation. Judging from 14 biometric indices out of 19 indices analyzed, middle-aged generative plants in 2015 surpass those in 2016. Indices that characterize the vitality structure are higher in 2015. The vitality type of the coenopopulation varies from prospering to depressive. Variations in biometric and vitality indices are associated with changing weather conditions during the vegetation period. In 2015, there were optimal conditions for plants to grow and develop.

Co‐evolutionary relationships of plants and fungi are of great importance for the phylogeny of both groups. Nyssa was widely distributed in the northern hemisphere during the Cenozoic. Extant species of Nyssa exhibit a disjunct distribution between eastern North America, Central America and East Asia. Here, a new species, Nyssa nanningensis Xu & Jin, is described based on fruit endocarps from the upper Oligocene Yongning Formation of the Nanning Basin, South China. This new fossil record of Nyssa expands the known palaeogeographical distribution of the genus to the low latitudes of East Asia. Associated fossil fungal fruiting bodies on Nyssa endocarps are assigned to the new fossil genus and species, Yongnicta nyssae Tobias & Maslova. This new genus is similar to some members of extant wood destructor taxa Coronophorales and Amphisphaeriales (Sordariomycetes, Ascomycota). About 3% of the Nyssa endocarps studied were affected by Yongnicta nyssae. Low frequency of fruit damage indicates that endocarps could be released from mesocarps by animals eating fleshy parts of fruits, making them potentially available to wood‐destroying fungi. [ABSTRACT FROM AUTHOR]

The unique co‐occurrence of thyriothecia belonging to three fossil genera of epiphyllous fungi, Stomiopeltites Alvin & Muir (Micropeltidaceae), Callimothallus Dilcher, and Trichothyrites Rosendahl (Microthyriaceae), are reported on the leaves of the same host plant, Cunninghamia shangcunica Kodrul, Gordenko & Sokolova from the Oligocene Shangcun Formation of the Maoming Basin, South China. In China, Stomiopeltites is identified for the first time, Callimothallus is known from the Oligocene and Miocene of Guangxi and Zhejiang provinces, and Trichothyrites previously has been found only in the Eocene palynological assemblages of the Maoming Basin. The presence of abundant and diverse epiphyllous micromycetes, together with the taxonomic composition of the Shangcun megaflora and pollen assemblage, as well as quantitative climatic estimates obtained using Climate Leaf Analysis Multivariate Program, confirm the existence of a warm and humid climate in this region during the late early Oligocene. The geographic and stratigraphic distributions, comparisons with extant analogues, as well as ecological and paleoclimatic implications of the fossil fungi are discussed. [ABSTRACT FROM AUTHOR]

The genus Burretiodendron Rehder is currently endemic to an area near the China–Vietnam border and the limestone mountains of Thailand and Myanmar. The fossil records of this genus were previously found only from the Miocene of Yunnan, Southwest China, and the Oligocene of Guangxi, South China. Here, we describe fossil fruits and associated leaves of Burretiodendron, which were discovered in the lower Oligocene Shangcun Formation of the Maoming Basin, Guangdong, South China. Morphological comparison with extant and fossil Burretiodendron taxa indicates that fruit fossils belong to the species Burretiodendron parvifructum J. Lebreton Anberrée & Z. K. Zhou. This is one of the earliest fossil records of the genus, providing additional evidence for the early biogeographic history of this genus and supporting the inference that the genus originated in South China. According to the habitat conditions of modern species, we speculate that there were limestone mountains around the Maoming Basin in the early Oligocene. [ABSTRACT FROM AUTHOR]

Premise: Microclimatic differences between the periphery and the interior of tree crowns result in a variety of adaptive leaf macromorphological and anatomical features. Our research was designed to reveal criteria for sun/shade leaf identification in two species of evergreen oaks, applicable to both modern and fossil leaves. We compared our results with those in other species similarly studied. Methods: For both Quercus bambusifolia and Q. myrsinifolia (section Cyclobalanopsis), leaves from single mature trees with well‐developed crowns were collected in the South China Botanical Garden, Guangzhou, China. We focus on leaf characters often preserved in fossil material. SVGm software was used for macromorphological measurement. Quantitative analyses were performed and box plots generated using R software with IDE Rstudio. Leaf cuticles were prepared using traditional botanical techniques. Results: Principal characters for distinguishing shade and sun leaves in the studied oaks were identified as leaf lamina length to width ratio (L/W), and the degree of development of venation networks. For Q. myrsinifolia, shade and sun leaves differ in tooth morphology and the ratio of toothed lamina length to overall lamina length. The main epidermal characters are ordinary cell size and anticlinal wall outlines. For both species, plasticity within shade leaves exceeds that of sun leaves. Conclusions: Morphological responses to sun and shade in the examined oaks are similar to those in other plant genera, pointing to useful generalizations for recognizing common foliar polymorphisms that must be taken into account when determining the taxonomic position of both modern and fossil plants. [ABSTRACT FROM AUTHOR]

Abstract Films of nanocrystalline silicon (nc-Si) were prepared from hydrogenated amorphous silicon (a-Si:H) by using rapid thermal annealing. The formed nc-Si films were subjected to stain etching in hydrofluoric acid solutions in order to passivate surfaces of nc-Si. The optical reflectance spectroscopy revealed the nc-Si formation as well as the high optical quality of the formed films. The Raman scattering spectroscopy was used to estimate the mean size and volume fraction of nc-Si in the annealed films, which were about 4 to 8 nm and 44 to 90%, respectively, depending on the annealing regime. In contrast to as-deposited a-Si:H films, the nc-Si films after stain etching exhibited efficient photoluminescence in the spectral range of 600 to 950 nm at room temperature. The photoluminescence intensity and lifetimes of the stain etched nc-Si films were similar to those for conventional porous Si formed by electrochemical etching. The obtained results indicate new possibilities to prepare luminescent thin films for Si-based optoelectronics.

The modern genus Dacrycarpus (Endl.) de Laub. of the family Podocarpaceae, containing nine species, is mainly distributed in tropical mountain rainforests of the southwestern Pacific region, ranging from New Zealand to low‐latitude Asia. This genus has abundant fossil records in both hemispheres, but all the known megafossils were limited to Australasia and South America. Here we report on Dacrycarpus guipingensis sp. nov. from the Miocene Erzitang Formation of Guangxi, South China. This is the first megafossil of Dacrycarpus in the Northern Hemisphere. The new species is represented by mummified dimorphic foliage, ovuliferous shoots, and a male cone with in situ pollen. It resembles the extant Dacrycarpus imbricatus (Blume) de Laub., which is common in rainforests from southern China and northern Myanmar to Fiji. This paper presents the first data on the anatomical structure of seed cone and exine ultrastructure of Dacrycarpus in situ pollen grains from a fossil material by using computed tomography scanning and ultrathin sectioning. For comparative purpose, data on the pollen morphology and ultrastructure were obtained for modern D. imbricatus for the first time. The D. guipingensis fossils strongly suggest the Miocene arrival of Dacrycarpus in Asia from the Southern Hemisphere. Based on the modern ecological niche and related fossil elements, this fossil locality was probably covered by conifer–broad‐leaved mountain rainforests during the Miocene. [ABSTRACT FROM AUTHOR]

Monsoonal climates at low latitudes (< 32°N) are an inevitable consequence of seasonal migrations of the Inter-tropical Convergence Zone (ITCZ), but the character of these monsoons depends on continental configuration, orographic expression and the strength of Hadley circulation. To explore the evolution of monsoon systems across southern Asia we compare climate signatures archived in ten Paleogene floras from northern India, Tibet and southern China, occupying low palaeolatitudes at a time of extreme global warmth and elevated CO 2 . Fossil leaf form reveals that under such 'hothouse' conditions megathermal early Eocene to earliest Miocene forests were exposed to strong monsoonal climates typical of those experienced today arising from annual migrations of the ITCZ, possibly enhanced by a lower equator-to-pole temperature gradient. Throughout the Paleogene an elevated Tibetan highland produced no discernable modification of this ITCZ monsoon, although rainfall seasonality similar to that of the modern South Asia Monsoon (SAM) is observed in northern India as early as the beginning of the Eocene, despite its near-equatorial palaeoposition. In South China rainfall seasonality increased progressively achieving modern monsoon-like wet season/dry season precipitation ratios by the early Oligocene. Despite evidencing weak rainfall seasonality overall, fossil leaves from South China have exhibited monsoon-adapted morphologies, comparable to those seen in today's Indonesia-Australia Monsoon, for at least 45 million years. Together, the Indian and South China fossil leaf assemblages show that the evolution of megathermal ecosystems across southern Asia has been influenced profoundly by monsoonal climates for at least the last 56 million years. The Paleogene ITCZ-driven monsoon system strongly impacted India as it transited the Equator likely eliminating Gondwanan taxa not able to adapt to seasonal precipitation extremes. Furthermore, powerful seasonally-reversing winds, and associated surface ocean currents, are likely to have facilitated two-way biotic transfer between India and Eurasia long before closure of the Tethys Ocean. [ABSTRACT FROM AUTHOR]