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Understanding the process of signal communication between pollen and stigma is of significant importance for plant sexual reproduction. In the case of inter‐subgeneric hybridization in water lily, a pre‐fertilization hybridization barrier exists, the regulatory mechanism of which remains unclear. In this study, we conducted hormone and transcriptome analyses of unpollinated stigmas (Mock), self‐pollinated stigmas (SP), cross‐pollinated stigmas within the same subgenus (CP), and inter‐subgenus cross‐pollination stigmas (ISCP) in water lily to elucidate the formation mechanism of the inter‐subgeneric hybridization barrier. Our results indicated that the lack of abscisic acid (ABA) and brassinolide (BR) in ISCP stigmas are key factors contributing to the formation of the inter‐subgeneric hybridization barrier in water lily. Exogenous application of ABA and BR can help overcome the barrier between inter‐subgeneric water lily crosses. Through transcriptome analysis, we identified nine candidate genes involved in regulating the inter‐subgeneric hybridization barrier in water lily. In addition, we further demonstrated the importance of the NCED2‐mediated ABA synthesis pathway in the pollination process through AS‐ODN technology. Our study confirms that ABA and BR are critical for breaking the inter‐subgeneric hybridization barrier. The identification of the nine candidate genes provides important clues for further research on the hybridization recognition mechanism in water lily. [ABSTRACT FROM AUTHOR]

Broccoli (Brassica oleracea var. italica) is an important B. oleracea cultivar, with high economic and agronomic value. However, comparative genome analyses are still needed to clarify variation among cultivars and phylogenetic relationships within the family Brassicaceae. Herein, the complete chloroplast (cp) genome of broccoli was generated by Illumina sequencing platform to provide basic information for genetic studies and to establish phylogenetic relationships within Brassicaceae. The whole genome was 153,364 bp, including two inverted repeat (IR) regions of 26,197 bp each, separated by a small single copy (SSC) region of 17,834 bp and a large single copy (LSC) region of 83,136 bp. The total GC content of the entire chloroplast genome accounts for 36%, while the GC content in each region of SSC,LSC, and IR accounts for 29.1%, 34.15% and 42.35%, respectively. The genome harbored 133 genes, including 88 protein-coding genes, 37 tRNAs, and 8 rRNAs, with 17 duplicates in IRs. The most abundant amino acid was leucine and the least abundant was cysteine. Codon usage analyses revealed a bias for A/T-ending codons. A total of 35 repeat sequences and 92 simple sequence repeats were detected, and the SC-IR boundary regions were variable between the seven cp genomes. A phylogenetic analysis suggested that broccoli is closely related to Brassica oleracea var. italica MH388764.1, Brassica oleracea var. italica MH388765.1, and Brassica oleracea NC_0441167.1. Our results are expected to be useful for further species identification, population genetics analyses, and biological research on broccoli. [ABSTRACT FROM AUTHOR]

Far‐travelled ash layers from explosive volcanic eruptions can provide invaluable marker horizons for dating and correlating regional to global sedimentary archives. Here, we present a new cryptotephra associated with the ~5.9 cal ka bp Towada‐Chuseri eruption (To‐Cu) in a peat sediment record from northeast China. This tephra exhibits a rhyolitic glass composition that can be distinguished from other widespread tephra layers around the region of Japan and northeast China. Our findings extend the known range of this ash significantly, making it now traceable about 1200 km from its source, Towada volcano, Japan. Notably, this tephra provides an important isochron for synchronising palaeoenvironmental studies during the mid‐Holocene period from the western Pacific, central Japan, Japan Sea and northeast China. [ABSTRACT FROM AUTHOR]

North Pacific Ocean sediments are important archives of geomagnetic field and paleoenvironmental evolutions, yet late Quaternary sedimentary sequences in the North Pacific Ocean are less explored because of generally low sedimentation rates and the challenge of dating sediments deposited below the calcite compensation depth. Core NP02 sediments from the North Pacific Ocean contain three visible tephra layers, which are identified as the To‐Of, Spfa‐1, and Kt‐3 tephra, respectively. An age model for core NP02 is established based on tephra correlation and one radiocarbon date, which gives a mean sedimentation rate of ∼11.6 cm/kyr. Magnetic analyses suggest the dominance of two remanence carriers; detrital vortex state and biogenic single domain magnetite. Variable depth offsets between the relative paleointensity (RPI) signals carried by the two remanence carriers adds a negligible age error (<0.5 kyr) to the core NP02 RPI record. Pronounced RPI amplitude variations are observed, and the Rockall and Laschamp excursions are identified in the core NP02 RPI record based on the age model. The fidelity of the core NP02 RPI record is further verified by comparison with other RPI stacks and records, and we demonstrate that the RPI variations can assist in chronology refinement. Plain Language Summary: The North Pacific Ocean is too deep to preserve materials effectively for the oxygen isotope chronology, and sediments deposit slowly in this region. Therefore, dating is a big problem for late Quaternary sedimentary cores. In this study, core NP02 sediments from the North Pacific Ocean are studied. The To‐Of, Spfa‐1, and Kt‐3 tephra layers are identified in core NP02 sediments based on the geochemical features. An age model for this core is reconstructed with the aid of tephra ages and one radiocarbon date. Magnetic analyses suggest that both small biogenic and relatively large detrital magnetite record geomagnetic information, and the two groups of magnetite deposit at about the same time. Based on the age model, core NP02 RPI record preserves the Rockall and Laschamp excursions, and the RPI pattern is consistent with other RPI stacks and records, which verifies core NP02 RPI fidelity. Therefore, we demonstrate that RPI variations is a promising dating tool for North Pacific Ocean sediments. Key Points: We use an age model based on tephra correlation and one radiocarbon date to assess the fidelity of relative paleointensity variationsDetrital vortex state and biogenic single domain magnetite are the dominant remanence carriers, and they introduced <0.5 kyr age errorAssessment of component‐specific magnetic properties should be considered to ensure the reliability of relative paleointensity variations [ABSTRACT FROM AUTHOR]

Volcanic ash has been widely used as unique independent marker horizons for dating and synchronizing paleoenvironments and archeological records. Here, we report a series of key widespread late Pleistocene to Holocene tephras horizons from a lake sequence in southern China that have significant potential for dating and synchronizing paleoenvironmental records from East Asia. Translatitudinal paleoclimatological, paleoenvironmental, and archeological correlations from the tropical Philippines, mainland China, and midlatitude Japan are achievable through these extensively distributed tephras, including synthetic studies of the Younger Dryas and mid‐Holocene climate events. Additionally, we establish refined ages for four pre‐1991 Pinatubo eruptions and date three late Pleistocene Luzon eruptions based on the lake sequence age model, which will facilitate future studies of tropical volcanic eruptions' forcing of climate change. Our results highlight the volcanic hazards around densely populated East Asia, and bring solutions to resolving dating uncertainty in the synchronization of rapid climate events across the region. Plain Language Summary: Tephra layers have been hailed as valuable independent age‐equivalent marker layers for precisely correlating archives of past environmental change. Japan and south‐east Asia have the most active land‐based volcanoes on Earth, and ash from their eruptions can be traced as far as the polar ice cores. However, the volcanic histories and products from the regions are poorly constrained, limiting the ability to recognize the eruptions' wider climate and societal impacts, and to use far‐traveled ash as dating horizons. In this study, we investigated cryptotephra (volcanic ash particles that are invisible to the naked eye) in a lake sequence from southern China. Cryptotephra from the Philippines, Japan, and South Korea was identified in the lake sediment. The discovery of these tephras in southern China significantly extends the volcanic ash distributions of several known late Pleistocene to Holocene eruptions from this region, and indicates that these prehistoric eruptions may have frequently impacted on some of the most densely populated parts of East Asia. These extensively distributed tephras will provide excellent dating horizons for future climate studies in this region. Key Points: We present the first high‐resolution late Pleistocene to Holocene cryptotephra sequence in mainland ChinaA series of key widespread late Pleistocene to Holocene tephra isochrons around East Asia is establishedWe refine the dating of late Pleistocene to Holocene eruptions from Pinatubo and a volcano from southwest Luzon [ABSTRACT FROM AUTHOR]

Background: Polycystic Ovary Syndrome (PCOS) is a major cause of anovulatory infertility. Some studies showed that miRNAs were used as diagnostic/prognostic biomarkers for various diseases.Objective: To identify candidate miRNAs in Granulosa Cells (GCs) of PCOS and evaluate their potential values for PCOS diagnosis.Methods: We screened differentially expressed miRNAs in GCs between PCOS and controls by the microarray data from the GEO database. GCs were collected from 21 controls and 24 PCOS. The candidate miRNAs were verified by qRT-PCR. The correlation was investigated between candidate miRNAs and clinical characteristics in participants. Diagnostic value of candidate miRNAs was analyzed by receiver operating characteristic (ROC) curve.Results: Seven miRNAs were differentially expressed in PCOS compared with controls. Furthermore, the validation results demonstrated that hsa-miR-3188 and hsa-miR-3135b showed higher levels in GCs with PCOS patients (p< 0.05). In addition, the expressions of hsa-miR-3188 and hsa-miR-3135b were negative correlated with FSH and hsa-miR-3188 was positive correlated with BMI (p< 0.05). ROC analysis indicated that hsa-miR-3188 and hsa-miR-3135b could differentiate PCOS from controls, and the hsa-miR-3188/3135b improved the predictive accuracy for PCOS.Conclusions: The expressions of hsa-miR-3188 and hsa-miR-3135b in human GCs were significantly associated with PCOS. Moreover, the hsa-miR-3188/3135b has certain diagnostic value for distinguishing PCOS. [ABSTRACT FROM AUTHOR]

The prose works composed by the ancient female writers revealed the rich images and the mental worlds of female authors. Influenced by the trend of liberation of individual personality after the Mid-Ming Dynasty, on the one hand, they were discernibly guarded by the attitude highlighting "virtues" in the compositions by female writers; on the other hand, they were reconstructed with the stance of "developing virtues" by emphasizing emotions somehow and its tradition of composition, reflecting the values which integrated both talents and virtues as well as virtues and emotions. Part of the female writers had the consciousness of "achieving glory from writing" and expected attaining immortality from their writing. They sought potential pursuit for accomplishing their individual values. Their works expressed their sympathy and pity for the unfortunate women, and were also integrated somehow with their examination and questioning on the experiences of traditional women. [ABSTRACT FROM AUTHOR]

Abstract: Prehistoric Holocene eruptions of Changbaishan volcano in Northeast China are poorly dated, with the exception of the 946 CE Millennium eruption. Poorly refined age estimates for the earlier eruptions present problems for the reconstruction of the eruptive history of the volcano. The Qixiangzhan eruption (QE) is a major controversial event in terms of its eruptive timing (ranging from ~88 to ~4 kyr) and style (effusive or explosive). As a result of the imprecise age estimates for the eruption, a geomagnetic field excursion recorded within the QE comendite has been variably correlated with a number of different excursion events observed elsewhere. In this study, a visible early Holocene tephra was identified in Yuanchi Lake, ~30 km east of the Changbaishan volcanic vent, and was dated to 8831‐8100 cal yr BP using Bayesian age modelling. Glass shard compositions enable the correlation of this tephra with the poorly dated QE, as well as with a tephra (SG14‐1058) recorded in Lake Suigetsu, in central Japan. These correlations confirm that the QE was explosive and that the ash from the QE can serve as an important early Holocene marker bed across East Asia. In addition, we propose an age of ~8100 cal yr BP for the QE based on the precise date of the Suigetsu SG14‐1058 tephra. Our results also confirm that the geomagnetic field excursion recorded in the Qixiangzhan comendite dates to ~8100 cal yr BP. [ABSTRACT FROM AUTHOR]

A detailed tephrostratigraphy of an active volcano is essential for evaluating its eruptive history, forecasting future eruptions and correlation with distal tephra records. Changbaishan volcano is known for its Millennium eruption (ME, AD 940s; VEI 7) and the ME tephra has been detected in Greenland ice cores ∼9000 km from the vent. However, the pre-Millennium (pre-ME) and post-Millennium (post-ME) eruptions are still poorly characterized. In this study, we present a detailed late Holocene eruptive sequence of Changbaishan volcano based on single glass shard compositions from tephra samples collected from around the caldera rim and flanks. Tephra ages are constrained by optically stimulated luminescence (OSL) and AMS 14 C dates. Tephra from the mid-Holocene pre-ME eruption can be divided into two pyroclastic fall subunits, and it cannot be correlated with any known Changbaishan-sourced tephra recorded in the Japan Sea based on major element composition of glass shards, such as the B-J (Baegdusan-Japan Basin) and B-V (Baegdusan-Vladivostok-oki) tephras. ME pyroclastic fall deposits from the caldera rims and volcanic flanks can be correlated to the juvenile pumice lapilli or blocks within the pyroclastic density current (PDC) deposits deposited in the valleys around the volcano based on glass shard compositions. Our results indicate that the glass shard compositions of proximal ME tephra are more varied than previously thought and can be correlated with distal ME tephra. In addition, widely-dispersed mafic scoria was ejected by the ME Plinian column and deposited on the western and southern summits and the eastern flank of the volcano. Data for glass from post-ME eruptions, such as the historically-documented AD 1403, AD 1668 and AD 1702 eruptions, are reported here for the first time. Except for the ME, other Holocene eruptions, including pre-ME and post-ME eruptions, had the potential to form widely-distributed tephra layers around northeast Asia, and our dataset provides a proximal reference for tephra and cryptotephra studies in surrounding areas. [ABSTRACT FROM AUTHOR]

The Changbaishan Millennium eruption (~ AD 940s) produced a widely distributed tephra layer around northeast Asia. This tephra layer serves as a marker bed in Greenland ice cores and in marine, lake, archeological and tsunami sediments in Japan and the surrounding region. However, little attention has been paid to the widespread sediments west of Changbaishan volcano. Here we present new stratigraphic, geochemical, varve chronology, and 14 C geochronological data from the varved sediments in Lake Sihailongwan, Longgang volcanic field, Northeast China, extending the westerly margin of this eruption. The distinctive geochemical characteristic of volcanic glass (ranging from trachyte to rhyolite), similar to those of proximal and distal tephra, confirmed the occurrence of Changbaishan Millennium eruption ash in the lake, illustrating the westward dispersal fan of the ash deposits. The position of the peak concentration of glass shards of this tephra was dated to 953 ± 37 AD by varve chronology, and the radiocarbon samples immediately above this tephra gave a date of 940–1020 AD, overlapping the most recent ages for this eruption. The occurrence of Changbaishan Millennium eruption ash in this lake enables a direct and precise synchronization with other high-resolution archives in Northeast Asia, such as maar lakes and peat and marine sediments, thus providing an isochronous marker for a range of sedimentary contexts. [ABSTRACT FROM AUTHOR]

• The chloroplast genome of Nymphaea had gene loss. • The ycf2 gene was positively selected. • Nymphaea can be divided into five subgenera. Although there has been a long history of cultivation and research on Nymphaea , the taxonomic relationships and evolutionary relationships among Nymphaea species remain controversial. The chloroplast (cp) genome can provide a new method to determine species origin, evolution, and phylogenetic relationships of Nymphaea. The complete cp genomes of seven Nymphaea species were sequenced by high-throughput sequencing technology, and the structural characteristics and phylogenetic relationships of cp genomes were analyzed. The cp genomes of seven species of Nymphaea had rich variation in large single-copy (LSC) and small single-copy (SSC) regions. A comparative cp genomic analysis of seven Nymphaea species showed that the cp gene sequence of Nymphaea was consistent, with no signs of reverse rearrangement. Using N. colorata as the reference sequence, a total of 8328 single nucleotide polymorphisms (SNPs) and 1579 insertions/deletions were obtained. The degree of variation of the cp genome of the seven Nymphaea species in rpoA – rpl20 , rbcL – ndhC , ndhD – ndhF , and trnN-GUU – ndhA regions was relatively high. The ycf2 gene was positively selected. The phylogenetic analysis showed that the genus Nymphaea can be further divided into five subgenera. [ABSTRACT FROM AUTHOR]

"Maars and Environment" highlights maar research in China and sheds light on the wealth of information a maar volcano can store from the pure volcanology to understanding magma fragmentation to the sedimentology of deep lacustrine basins which record changing environmental conditions. Furthermore, maar volcanoes are the type of small-volume, monogenetic volcanoes where the rising magma can strongly influence the environment. This Special Issue will provide a snapshot of maar research especially from the maars and their environmental aspects. [Extracted from the article]

Abstract The thick late Cenozoic deposits of Huaibei Plain provide a record of paleoenvironmental changes in the northern and southern transitional zone of eastern China, and of the evolution of the Asian monsoon system. A detailed magnetostratigraphic study of the Huainan (HN, 481.45-m deep) drill core from the center of Huaibei Plain reveals a magnetic polarity sequence from chron C4n.2n to chron C1n, spanning the interval from ∼8 Ma to the present; it is the first reliable magnetostratigraphic chronology for the late Miocene to present for Huaibei Plain. The stratigraphic sequence contains three intervals characterized by major peaks in magnetic susceptibility (at depths of 58.8 m, 108.0 m and 312.4 m), which can be used as isochronous marker beds for regional stratigraphic correlations in Huaibei Plain. Major changes in sediment grain-size occur at 7.0 and 1.7 Ma, corresponding to pronounced environmental shifts, which we consider reflect the respective strengthening of the South Asian summer monsoon and East Asian winter monsoon at these times. Highlights • Magnetostratigraphy of a drill core from Cenozoic sediments in East China reveals a continuous 8 Myr sequence. • Grain-size data indicate pronounced environmental changes at ∼7.0 and ∼1.7 Ma. • Late Cenozoic sediments of Huaibei Plain can be correlated by three peaks in magnetic susceptibility. • Paleoenvironmental changes at ∼7.0 and ∼1.7 Ma were directly linked to changes in the Asian monsoon system. [ABSTRACT FROM AUTHOR]

The sediments of the Huaibei Plain in semi-humid mid-eastern China represent valuable geological records with respect to eolian–fluvial interactions, depositional environments, and climate change in this region. Provenance and weathering conditions are often reconstructed using sedimentary geochemistry methods. In this study, an 8-m core from Huainan and a set of loess samples from northern and southern China were analyzed for major, trace, and rare earth elements (REEs). Results were compared to determine the samples’ provenance. The major, trace, rare earth elements contents, and grain size distribution were found to fluctuate widely in the 2–8 m section of the Huainan core and more narrowly closer to the surface (0–2 m). This suggests a provenance shift at a depth of 2 m. The TiO 2 /Al 2 O 3 , SiO 2 /Al 2 O 3 , Th/Nb, La/Nb values and REE patterns in the upper core (0–2 m) are similar to those found in samples from the Chinese Loess Plateau (CLP). These results suggest that the CLP in northern China is likely to be the primary origin of the upper part (0–2 m) of the Huainan core. Compared with CLP samples, the upper part of the Huainan core exhibits lower K 2 O/Al 2 O 3 values and higher chemical alteration indices. This is indicative of the material’s substantial weathering during transportation and re-deposition and implies that these sediments could reasonably be classified as typical recycled loess. The sediments may have been transported from the CLP to Huainan as Yellow River flood events, probably during the last deglaciation (∼13.2 ka) as a result of increased precipitation, along with glacier and snow melt in the upper reaches of the Yellow River catchment during this period. This suggests that the Yellow River may have migrated into the Huaihe River catchment much earlier than the earliest historical records (361 BCE) suggest. The implications of this would be profound with respect to Chinese history. [ABSTRACT FROM AUTHOR]

• The lithospheric mantle of the eastern Qiangtang block was metasomatized by subduction related fluids/melts. • Partial melting at different depths and degrees produced various parental magmas. • Magmatic recharge contributed to the wide range of ratios between highly incompatible elements. • Continental subduction of the Songpan-Ganzi block triggered crustal thickening and surface uplift. • The surface of the eastern Qiangtang block reached a moderate elevation (<~3 km) in the late Eocene. Post-collisional magmatism offers significant clues to reveal the deep dynamic process and surface uplift of plateaus. New zircon U-Pb ages, biotite Ar-Ar ages, zircon trace elements, and whole-rock geochemistry, integrated with published data of igneous rocks from the eastern Qiangtang block (eastern Tibetan Plateau) were determined to unravel the geodynamics and constrain the uplift history. These igneous rocks consist of few mafic and many intermediate-felsic series. Geochronological studies reveal that the magmatism mainly occurred in ~43–33 Ma. The late Eocene igneous rocks are characterized by high potassium, enrichment in large ion lithophile elements (LILE, e.g., Rb, Ba, Th, U), depleted in high field strength elements (HFSE, e.g., Nb, Ta, Ti), negligible Eu anomalies, with a wide range of highly incompatible element ratios. The parental magmas of these rocks were most probably generated by different degrees of partial melting of the lithospheric mantle, which were heterogeneously metasomatized by subduction related multiphase fluids/melts. Whole-rock geochemistry, zircon trace elements, and thermodynamic modeling results suggest that the parental magmas experienced complicated and different differentiation processes. Mantle metasomatism, fractional crystallization, and magmatic recharge made contributions to the enrichment of incompatible elements and the wide range ratios between highly incompatible elements. In combination with the estimated Eocene crustal thickness, we suggest that the southward continental subduction of the Songpan-Ganzi block triggered the magmatism, thickened the crust, and induced the surface uplift to no more than ~3 km in the late Eocene. [ABSTRACT FROM AUTHOR]

Embryo abortion is the main cause of failure in chrysanthemum cross breeding, and the genes and proteins associated with embryo abortion are poorly understood. Here, we applied RNA sequencing and isobaric tags for relative and absolute quantitation (iTRAQ) to analyse transcriptomic and proteomic profiles of normal and abortive embryos. More than 68,000 annotated unigenes and 700 proteins were obtained from normal and abortive embryos. Functional analysis showed that 140 differentially expressed genes (DEGs) and 41 differentially expressed proteins (DEPs) were involved in embryo abortion. Most DEGs and DEPs associated with cell death, protein degradation, reactive oxygen species scavenging, and stress-response transcriptional factors were significantly up-regulated in abortive embryos relative to normal embryos. In contrast, most genes and proteins related to cell division and expansion, the cytoskeleton, protein synthesis and energy metabolism were significantly down-regulated in abortive embryos. Furthermore, abortive embryos had the highest activity of three executioner caspase-like enzymes. These results indicate that embryo abortion may be related to programmed cell death and the senescence- or death-associated genes or proteins contribute to embryo abortion. This adds to our understanding of embryo abortion and will aid in the cross breeding of chrysanthemum and other crops in the future.

Japanese encephalitis virus (JEV) is the leading cause of viral encephalitis in Asia and domestic pigs serve as the amplifying hosts. In the present study, the full genomic sequences of two JEV strains (HEN0701 and SH0601) isolated from pigs in China were determined and compared with other 12 JEV strains deposited in GenBank. These two strains had an 88.8% nucleotide sequence similarity and 97.9% deduced amino acid sequence homology. HEN0701 had high nucleotide sequence and high amino acid sequence identity with genotype I (GI) strains, while SH0601 had high nucleotide sequence and high amino acid sequence identity with GIII strains at both the gene and full genome levels. Further phylogenetic analysis showed that HEN0701 belonged to the JEV GI group and SH0601 was classified as a GIII strain. Analysis of codon usage showed there were a few differences between the GI and GIII strains in nucleotide composition and codon usage for the open reading frames.