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Abstract The golden camellia, a highly valued ornamental plant, belongs to the Chrysantha section, the sole group in the Camellia genus that produces yellow flowers. The cultivation and broader application of this unique species have been significantly hindered by the scarcity of golden camellia and the limited knowledge of the molecular mechanisms governing yellow flower development. To investigate the dynamics of metabolite accumulation and gene expression during the yellow flower formation of C. perpetua, a continuously flowering golden camellia, a comprehensive metabolomic and transcriptomic analysis was performed across five distinct developmental stages. This analysis identified 1,160 metabolites, with flavonoids constituting the largest proportion at 21.6%. Comparative transcriptomic profiling indicated that differentially expressed genes (DEGs) associated with photosynthesis were predominantly active during the early stages of flower development, while DEGs involved in the flavonoid biosynthesis pathway showed a marked increase as the flowers matured. The integrated metabolomic and transcriptomic data highlighted the pivotal regulatory role of the flavonoid biosynthesis pathway in the formation of yellow flowers in C. perpetua, identifying 50 key genes and 17 crucial metabolites and mapping their interaction networks. Furthermore, weighted gene co-expression network analysis pinpointed several hub genes, such as flavonol synthase, which are likely critical to flavonoid production due to their elevated expression levels, particularly in the early bud and yellowing phases. This study provides valuable insights into the molecular pathways that underlie yellow flower development in golden camellia species.

The rare and endangered wild plant, Horsfieldia hainanensis, has been listed as a second-level key protected plant in China. Currently, its habitat is severely damaged, and the population has dramatically declined, necessitating urgent intervention for protection. In this study, the aim was to explore the correlations and differences from the perspectives of photosynthetic characteristics and leaf structure, providing scientific references for in-situ conservation and ex-situ cultivation. The results revealed the following: (1) The maximum net photosynthetic rate (Pmax) and light saturation point (LSP) of mature trees were significantly higher than those of seedlings, while the light compensation point (LCP), CO2 compensation point (CCP), and CO2 saturation point (CSP) were significantly lower in seedlings. (2) The average daily net photosynthetic rate of mature trees was significantly higher than that of seedlings. When both mature trees and seedlings exhibited a “midday depression” phenomenon, accompanied by an increase in intercellular CO2 concentration (Ci), it indicated that the “midday depression” was caused by non-stomatal limiting factors. (4) Both mature trees and seedlings showed peak values of water use efficiency (WUE) under low light conditions. Mature trees had smaller upper and lower epidermis thickness but larger leaf thickness, and their leaf structure, characterized by well-developed palisade and spongy tissues, conformed to the cellular structure adaptations for low light. Therefore, both were more adapted to low light conditions. (5) The stomatal density (SD) and individual stomatal area (SA) of seedlings were significantly higher than those of mature trees. (6) The total chlorophyll content of mature trees was significantly higher than that of seedlings, while the chlorophyll a/chlorophyll b ratio was significantly lower in mature trees and remained below three in both cases. In summary, the photosynthetic capacity and light adaptability of mature trees are stronger than those of seedlings, but both mature trees and seedlings exhibit shade-tolerant characteristics. For in-situ conservation, it is possible to promote the growth and development of seedlings by appropriately employing artificial “windowing” or shading methods based on the actual growth environment of the seedlings. In the case of ex-situ cultivation, seedlings should be provided with appropriate shading initially, while ensuring sufficient moisture and CO2 concentration. As the plants grow, the shading intensity can be gradually reduced. Once the plants reach maturity, they have a broader range of light adaptability and can be transplanted to environments with less shading.

Yellow Camellia is an endangered and protected wild plant with unique medicinal value. Among the Camellia Sect. Chrysantha Chang, certain species (e.g. Camellia limonia) can grow in karst regions. The karst region is a highly sensitive ecosystem with low environmental capacity. However, the molecular mechanisms underlying the adaptation of yellow camellia to karst regions remain unclear. Here, we present a high-quality genome with 15 chromosome groups with an N50 of 198.92 Mb. The divergence between C. limonia and Camellia sinensis occurred approximately 6 million years ago, indicating that the Himalayan uplift event may led to species differentiation. This enables C. limonia to thrive in a unique ecological environment like the karst region. Flavonoid compounds play a significant role in the interaction between plants and their environment. In comparison to Theaceae family genomes, C. limonia exhibits an increased number of gene family members involved in the flavonoid biosynthesis pathway, including UDP-glycosyltransferases and chalcone reductase. Additionally, two gene clusters associated with flavonoid biosynthesis were identified in the genome of C. limonia. Furthermore, comparative genomics analysis revealed the expansion of genes associated with karst environment adaptation in the genome of C. limonia, such as calmodulin genes and genes related to Calcium ion transmembrane transport. Additionally, at the gene expression level, it was observed that the secondary metabolism-related genes may be involved in the calcium tolerance of C. limonia. These findings provide important insights into the evolution of C. limonia, offering references for the study of plants in karst areas.

Abstract Background Flowering at the right time is a very important factor affecting the stable annual yield of longan. However, a lack of knowledge of the regulatory mechanism and key genes of longan flowering restricts healthy development of the longan industry. Therefore, identifying relevant genes and analysing their regulatory mechanism are essential for scientific research and longan industry development. Results DlLFY (Dimocarpus longan LEAFY) contains a 1167 bp open reading frame and encodes 388 amino acids. The amino acid sequence has a typical LFY/FLO family domain. DlLFY was expressed in all tissues tested, except for the leaf, pericarp, and pulp, with the highest expression occurring in flower buds. Expression of DlLFY was significantly upregulated at the early flower induction stage in “SX” (“Shixia”). The results of subcellular localization and transactivation analysis showed that DlLFY is a typical transcription factor acting as a transcriptional activator. Moreover, overexpression of DlLFY in Arabidopsis promoted early flowering and restrained growth, resulting in reduced plant height and rosette leaf number and area in transgenic plants. DNA affinity purification sequencing (DAP-Seq) analysis showed that 13 flower-related genes corresponding to five homologous genes of Arabidopsis may have binding sites and be putative target genes. Among these five flower-related genes, only AtTFL1 (terminal flower 1) was strongly inhibited in transgenic lines. Conclusion Taken together, these results indicate that DlLFY plays a pivotal role in controlling longan flowering, possibly by interacting with TFL1.

Abstract Whether ex situ populations constructed in the limited nursery resources of botanical gardens can preserve enough genetic diversity of endangered plants in the wild remains uncertain. Here, a case study was conducted with Camellia tunghinensis, which is one of the species with the lowest natural distribution area in the sect. Chrysantha (golden camellia) of the family Theaceae. We investigated the genetic diversity and population structure of 229 samples from wild and ex situ populations using genotyping by sequencing (GBS). Core germplasm was constructed from these samples. The results showed that wild C. tunghinensis exhibited high genetic diversity, with observed heterozygosity of 0.257–0.293 and expected heterozygosity of 0.247–0.262. Compared with wild populations, the genetic diversity of ex situ populations established by transplanting wild seedlings was close to or even higher. However, the genetic diversity of those established by seed or cuttings of a few superior trees was lower. The Admixture analysis revealed that the structure of the ex situ populations derived from seeds and cuttings was relatively simple compared with the ex situ populations derived from transplanted wild seedlings and wild populations. These results suggested that direct transplanting of wild seedlings was more conducive to preserving the genetic diversity of endangered plants in the wild. In addition, wild populations demonstrated a small differentiation (mean FST = 0.044) among themselves, possibly due to long‐term and frequent gene flow between the wild populations. In contrast, moderate differentiation (mean FST > 0.05) was detected among ex situ populations and between ex situ and wild populations. This may be the combined result of the absence of gene flow pathways and strong selection pressure in various ex situ environments. Finally, 77 core germplasms were extracted from 229, likely representing the genetic diversity of C. tunghinensis. This study provides future strategies for the ex situ conservation and management of the golden camellia species and other rare and endangered plants.

BackgroundFrailty correlates with adverse outcomes in many cardiovascular diseases and is prevalent in individuals with heart failure (HF). The Hospital Frailty Risk Score (HFRS) offers an integrated, validated solution for frailty assessment in acute care settings, but its application in critically ill patients with congestive HF lacks exploration. This study aimed to identify the association between frailty assessed by the HFRS and in-hospital mortality in critically ill patients with congestive HF.MethodsThis observational study retrospectively enrolled 12,179 critically ill patients with congestive HF. Data from the Medical Information Mart for Intensive Care IV database was used. The HFRS was calculated to assess frailty. Patients were categorized into three groups: non-frailty (HFRS

Abstract Background As the characteristic functional component in ginger, gingerols possess several health-promoting properties. Long non-coding RNAs (lncRNAs) act as crucial regulators of diverse biological processes. However, lncRNAs in ginger are not yet identified so far, and their potential roles in gingerol biosynthesis are still unknown. In this study, metabolomic and transcriptomic analyses were performed in three main ginger cultivars (leshanhuangjiang, tonglingbaijiang, and yujiang 1 hao) in China to understand the potential roles of the specific lncRNAs in gingerol accumulation. Results A total of 744 metabolites were monitored by metabolomics analysis, which were divided into eleven categories. Among them, the largest group phenolic acid category contained 143 metabolites, including 21 gingerol derivatives. Of which, three gingerol analogs, [8]-shogaol, [10]-gingerol, and [12]-shogaol, accumulated significantly. Moreover, 16,346 lncRNAs, including 2,513, 1,225, and 2,884 differentially expressed (DE) lncRNA genes (DELs), were identified in all three comparisons by transcriptomic analysis. Gene ontology enrichment (GO) analysis showed that the DELs mainly enriched in the secondary metabolite biosynthetic process, response to plant hormones, and phenol-containing compound metabolic process. Correlation analysis revealed that the expression levels of 11 DE gingerol biosynthesis enzyme genes (GBEGs) and 190 transcription factor genes (TF genes), such as MYB1, ERF100, WRKY40, etc. were strongly correlation coefficient with the contents of the three gingerol analogs. Furthermore, 7 and 111 upstream cis-acting lncRNAs, 1,200 and 2,225 upstream trans-acting lncRNAs corresponding to the GBEGs and TF genes were identified, respectively. Interestingly, 1,184 DELs might function as common upstream regulators to these GBEGs and TFs genes, such as LNC_008452, LNC_006109, LNC_004340, etc. Furthermore, protein–protein interaction networks (PPI) analysis indicated that three TF proteins, MYB4, MYB43, and WRKY70 might interact with four GBEG proteins (PAL1, PAL2, PAL3, and 4CL-4). Conclusion Based on these findings, we for the first time worldwide proposed a putative regulatory cascade of lncRNAs, TFs genes, and GBEGs involved in controlling of gingerol biosynthesis. These results not only provide novel insights into the lncRNAs involved in gingerol metabolism, but also lay a foundation for future in-depth studies of the related molecular mechanism.

Abstract Background Understanding genetic diversity is a core issue in conservation genetics. However, previous genetic diversity evaluations of narrowly distributed species have rarely used closely related widespread species as a reference. Furthermore, identifying natural hybridization signals between narrowly and widely distributed sympatric species is of great importance for the development of species conservation programs. Methods In this study, population genotyping by sequencing (GBS) was performed for a narrowly distributed species, Geodorum eulophioides (endemic and endangered in Southwest China), and a widespread species, G. densiflorum. A total of 18,490 high-quality single nucleotide polymorphisms (SNPs) were identified at the whole-genome level. Results The results showed that the nucleotide diversity and heterozygosity of G. eulophioides were significantly higher than those of G. densiflorum, confirming that narrowly distributed species can still preserve high genetic diversity. Consistent with taxonomic boundaries, all sampled individuals from the two species were divided into two genetic clusters and showed high genetic differentiation between species. However, in a sympatric population, a few G. eulophioides individuals were detected with genetic components from G. densiflorum, suggesting potential interspecific natural hybridization. This hypothesis was supported by Treemix analysis and hand-hybridization trials. Invasion of the habitat of G. eulophioides invasion by G. densiflorum under anthropogenic disturbance may be the main factor causing interspecific hybridization. Conclusions Therefore, reducing or avoiding habitat disturbance is a key measure to protect the G. eulophioides populations. This study provides valuable information for future conservation programs for narrowly distributed species.

The genus Ottelia comprises approximately 21 submerged macrophyte species primarily found in tropical Africa and Southeast Asia. The classification of several Ottelia species as vulnerable under the criteria “A2c” in the China Species Red List emphasizes the urgency of establishing a credible taxonomy. The ambiguity in taxonomy and evolutionary history persists, primarily stemming from the absence of a robust phylogeny at the species level. The rapid progress in high-throughput sequencing technology has facilitated the retrieval of complete chloroplast (cp) genome sequences, offering a molecular foundation for conducting phylogenetic analyses. In this study, the entire cp genomes of five samples of four Ottelia species were sequenced. All five Ottelia samples exhibited a circular, quadripartite-structured molecule, with lengths ranging from 156,823 to 162,442 bp. A total of 75–88 simple sequence repeats (SSRs) in the cp genomes of the five Ottelia samples were observed, which could be used for species identification. A preliminary phylogenetic analysis revealed that O. fengshanensis, O. acuminata, and O. guanyangensis clustered with strong support (100 BS). O. acuminata var. jingxiensis was resolved as a sister to O. acuminata var. lunanensis (100 BS), and both were further found to be sisters to O. balansae. The widely distributed O. alismoides exhibited a close phylogenetic relationship as the sister taxon to all the Chinese endemic taxa, supported by robust values. Together, our thorough examination of the entire cp genomes of the five Ottelia samples provides eminent insights into reconstructing their phylogeny. Furthermore, it illuminates the evolutionary dynamics of the cp genome within the Ottelia genus.

In order to study the calcium speciation characteristics in leaves of golden Camellia species under different habitats, 10 species of golden Camellia from calcareous soil habitats and four species from acidic soil habitats were used as the research objects. The calcium content (Soil-Ca) and pH (Soil-pH) of habitat soil, and the contents of calcium nitrate and calcium chloride (AIC-Ca), water soluble organic acid calcium (H2O-Ca), calcium pectate (NaCl-Ca), calcium phosphate and calcium carbonate (HAC-Ca), calcium oxalate (HCl-Ca), calcium silicate (Res-Ca), and total calcium (Tot-Ca) of leaves were measured. The results were as follows: (1) the Soil-Ca and Soil-pH of calcareous soil were extremely significantly (P

In order to clarify the nutritional value characteristics and development and utilization direction of different parts of the rare karst plant Malania oleifera,, the mature fruits, leaf, branch bark and bark of M. oleifera collected from Jiaole Tiankeng, Bama County, Hechi City, Guangxi were used as materials in this study. The types and contents of essential nutrients, amino acids and minerals in different parts of M. oleifera were determined by the national standard analysis method of food nutrients in China, and the nutritional values of amino acids in different parts were evaluated. The results were as follows: (1) In terms of essential nutrients, except for naphtha, there were extremely significant differences in the contents of the remaining six essential nutrients among five parts (P

In order to study the chemical constituents in the leaves of Champereia manillana var. longistaminea, the chemical composition was analyzed by the silica gel column chromatography (CC), thin-layer chromatography (TLC), dextran gel column chromatography (Sephadex LH-20), reversed-phase silica gel (RPC18) column chromatography and high performance liquid chromatography (HPLC). The ethyl acetate extraction part of the ethanol extraction was separated and six monomer compounds were obtained. The structures of these compounds were identified using nuclear magnetic resonance spectroscopy (NMR), high resolution mass spectrometry (HR-ESI-MS) and the data of the literature. Six compounds were elucidated as taraxerol (1), 1H-indole-3-carboxylic acid (2), (24R)-cycloartane-3β, 24, 25-triol (3), (24R, S)-3β-24,31-epoxy-24-methylcycloartane(4), 1-O-linolenoyl-3-O-β-D-galactospyranosyl-snglycerol (5), and hyloglyceride (6). All compounds 1-6 were isolated from this plant for the first time.

In this study, we prepared high-nitrogen self-doped porous carbons (NPC1 and NPC2) derived from the pruned branches and seeds of Zanthoxylum bungeanum using a simple one-step method. NPC1 and NPC2 exhibited elevated nitrogen contents of 3.56% and 4.22%, respectively, along with rich porous structures, high specific surface areas of 1492.9 and 1712.7 m2 g−1 and abundant surface groups. Notably, both NPC1 and NPC2 demonstrated remarkable adsorption abilities for the pollutant methylene blue (MB), with maximum monolayer adsorption capacities of 568.18 and 581.40 mg g−1, respectively. The adsorption kinetics followed the pseudo-second-order kinetics and the adsorption isotherms conformed to the Langmuir isotherm model. The adsorption mechanism primarily relied on the hierarchical pore structures of NPC1 and NPC2 and their diverse strong interactions with MB molecules. This study offers a new approach for the cost-effective design of nitrogen self-doped porous carbons, facilitating the efficient removal of MB from wastewater.

Vatica guangxiensis X. L. Mo (Dipterocaceae) is a valuable timber tree species endemic to China and a typical plant species with extremely small populations (PSESP). To understand the pattern variations in the genetic diversity of V. guangxiensis during natural regeneration, large-scale genome-wide SNPs were developed using genotyping by sequencing (GBS) to assess genetic diversity and population structure and to infer demographic history. The observed heterozygosity (HO), expected heterozygosity (HE), and nucleotide diversity (π) of V. guangxiensis were 0.1810, 0.2128, and 0.2178, respectively, demonstrating a low genetic diversity characteristic similar to most PSESP. However, further analysis of trees at different periods of natural regeneration revealed that both small trees and medium trees had lower genetic diversity than big trees. One important cause of the low and declining genetic diversity of V. guangxiensis may be the inbreeding that is forced due to the very small population size. Notably, a rare genetic component was detected in the genomes of several individuals in the medium tree and small tree groups, which may have been derived from other big trees that have died. In addition, the Tajima’D value (0.0689) and Stairway plot revealed a population bottleneck along with a continuous decline in the effective population size of V. guangxiensis since the last glacial period. These findings expand the understanding of the evolutionary history of the diversity of PSESP and the variation patterns in their genetic diversity, thus providing a basis to develop an effective conservation strategy.

In this study, the effects of bagging treatment on fruit appearance and internal quality, including fruit shape index, single fruit weight, fruit vitamin C, soluble solids, titratable acid, chlorophyll and carotenoid content, were studied by using ‘Donghong’ kiwifruit as experimental material. Meanwhile, the pesticide residues of bagged and non-bagged (NB) kiwifruit were compared and analyzed. Results showed that the pericarp color of bagged kiwifruit is lighter in green than that of NB group, with uniform color, cleaner appearance and no scabs and spots. Single fruit weight and transverse meridians of bagged kiwifruits were significantly increased. Interestingly, we found single bagging treatment had little effect on the internal quality of ‘Donghong’ kiwifruit. After pesticide treatment, the fruit shape of kiwifruit was rounder, significantly increased the weight, chlorophyll content of fruit, and decreased the content of vitamin C and carotenoids. In addition, bagging + pesticide treatment had additive effect on these characters. After bagging, the residues of pyraclostrobin and β-cypermethrin in ‘Donghong’ kiwifruit were significantly lower than those in the control. However, the residue of difenoconazole residues did not show significant difference. Bagging treatment has the ability to improve the appearance and reduce the residue of some pesticides. Meanwhile, the application of some pesticides can improve the single fruit weight and fruit quality. Therefore, bagging is a scientific and effective cultivation method in the green production of ‘Donghong’ kiwifruit.

Not only are the plants of the golden camellia group examples of high-quality camellia germplasm, but they are also a plant group with rich medicinal and nutritional value, and these plants are used as food, cosmetics and traditional medicine in China. There are approximately 50 species in this group around the world, and more than 30 species of golden camellia plants have been listed in China. The leaves and flowers of these species have similar shapes, and as such, they are often confused as the same species. Our study used simplified genome sequencing technology to construct a phylogenetic tree of plants in the Chinese golden camellia group, and we also described the evolutionary relationships. At the same time, the secondary metabolic indexes of the total phenols, total flavonoids, total anthocyanins and ellagic acid in the leaves were determined, and principal component clustering analysis was also performed. The results showed that the phylogenetic relationship and genetic distance among the plant species of Chinese golden camellia group plants were fully revealed. The cluster analysis of chemical secondary metabolism and genetic phylogenetic trees showed some of the same trends, thereby indicating that secondary metabolism golden camellia can be used as biomarkers for golden camellia. The research results provide phylogenetic information for the genotype and performance diversity of the golden camellia that is regionally distributed in China, as well as provide a theoretical basis for the research and development of potential bioactive substances.

Mycorrhizal fungi plays important roles in the seed germination and subsequent growth of orchids. The research of fungi in orchid roots, especially dominant mycorrhizal fungi is critical for orchids protection. In this study, the fungal community and composition of mycorrhizal fungi in roots, rhizomes and rhizosphere soil of Bulbophyllum tianguii grown in three terrestrial environments were analyzed by the second generation sequencing technology. The results of OTU clustering and α and β diversity analysis showed that there were significant differences in fungal communities in roots, rhizomes and rhizosphere soil of B. tianguii. The total number of OTUs in rhizomes was much less than that in roots and rhizosphere soil. The number of OTUs in rhizosphere soil and the diversity of mycorrhizal fungi were the highest. Meanwhile, the species and abundance of mycorrhizal fungi in roots and rhizomes of B. tianguii were different from those in rhizosphere soil. For different elevations, compared with B. tianguii that grow in middle of Tiankeng and top of Tiankeng, the OTUs number of B. tianguii in orchid garden is richest, and the diversity of mycorrhizal fungi in orchid garden was significantly higher than other locations. Among the three different habitats of B. tianguii, the number of OTUs in humus soil and stone habitats was notably higher than tree habitats, and the diversity of mycorrhizal fungi in humus soil was the highest. The analysis of mycorrhizal fungi in different habitats and altitudes of B. tianguii showed that Sebacina and Exophiala were the dominant mycorrhizal fungi in B. tianguii. The results of species annotation, phylogenetic tree and co-occurrence network analysis showed the dominant mycorrhizal fungi of B. tianguii mainly included Sebacina, Cladosporium, Exophiala, Fusarium. This study reveals the symbiotic relationship between Sebacina, Exophiala, Cladosporium and the B. Tianguii. It will provide a theoretical basis for the protection and biological function study of B. Tianguii.

BackgroundRadiotherapy plays an important effect on the standard therapy of esophageal squamous cell carcinoma (ESCC). However, the efficacy of the therapy is limited and a few patients do not achieve satisfactory treatment results due to the existence of radiation resistance. Therefore, it is necessary to identify the potential predictive biomarkers and treatment targets for ESCC.MethodsWe performed the whole-exome sequencing to determine the germline and somatic mutations in ESCC. Functional enrichment and pathway-based protein-protein interaction analyses were used to ascertain potential regulatory networks. Cell survival and cell death after treatment with radiotherapy were determined by CCK-8 and LDH release assays in ESCC cells. The correlations of NOTCH1 and tumor immune infiltration were also analyzed in ESCC.ResultsOur results showed that 344 somatic and 65 germline differentially mutated genes were detected to be radiosensitivity-related loci. The tumor mutational burdens (TMB) or microsatellite instability (MSI) were not significantly correlated with the response to radiotherapy in ESCC patients. Pathway-based protein-protein interaction analyses implied several hub genes with most nodes (such as PIK3CA, NOTCH1, STAT3 and KDR). The in vitro studies showed that the knockdown of NOTCH1 inhibited cell survival and rendered more cell death after the treatment with radiotherapy in ESCC cells, while NOTCH1 overexpression had the opposite effects. Moreover, NOTCH1, frequently up-regulated in ESCC, was negatively correlated with activated B cell and immature dendritic cell in ESCC. High expression of NOTCH1 was accompanied with the low levels of some immunotherapy-related cells, including CD8(+) T cells and NK cells.ConclusionsThese results indicate the differences of the germline mutations and somatic mutations between the radiosensitive and radioresistence groups in ESCC and imply that NOTCH1 plays important roles in regulating the radiosensitivity of ESCC. The findings might provide the biomarkers and potential treatment targets for improving the sensitivity to radiotherapy in ESCC.

The genus Ormosia comprises approximately 130 species, which are found in tropical regions all over the world. The taxonomy and evolutionary history are still ambiguous due to the lack of a solid phylogeny at the species level. Due to the fast advancement of high-throughput sequencing technology, it is now possible to retrieve the full chloroplast (cp) genome sequence, providing a molecular basis for phylogenetic analysis. Five species of Ormosia were used in this work, and their whole cp genomes were sequenced. One circular, quadripartite-structured molecule, ranging from 169,797 to 173,946 base pairs in length, was present in all five Ormosia species. The cp genomes of the five newly sequenced Ormosia species were further compared with the published cp genomes of O. pinnata. Ten hypervariable regions (Pi > 0.025) were uncovered in the Ormosia chloroplast genomes, among which petN-psbM showed the highest Pi value. Phylogenetic analysis revealed that O. microphylla and O. olivacea clustered with strong support. O. balansae was resolved as a sister to O. pinnata, and they were further found to be sisters to the remaining 13 Ormosia species. The cp genes of O. elliptica showed a close relationship to O. hosiei, and O. semicastrata clustered with O. emarginata. Taken together, the comprehensive analysis of the complete cp genomes of five Ormosia species offers valuable insight and information for reconstructing their phylogeny and sheds light on the evolutionary dynamics of the chloroplast genome in Ormosia.

Abstract Background Pilea is a genus of perennial herbs from the family Urticaceae, and some species are used as courtyard ornamentals or for medicinal purposes. At present, there is no information about the plastid genome of Pilea, which limits our understanding of this genus. Here, we report 4 plastid genomes of Pilea taxa (Pilea mollis, Pilea glauca ‘Greizy’, Pilea peperomioides and Pilea serpyllacea ‘Globosa’) and performed comprehensive comparative analysis. Results The four plastid genomes all have a typical quartile structure. The lengths of the plastid genomes ranged from 150,398 bp to 152,327 bp, and each genome contained 113 unique genes, including 79 protein-coding genes, 4 rRNA genes, and 30 tRNA genes. Comparative analysis showed a rather high level of sequence divergence in the four genomes. Moreover, eight hypervariable regions were identified (petN-psbM, psbZ-trnG-GCC, trnT-UGU-trnL-UAA, accD-psbI, ndhF-rpl32, rpl32-trnL-UAG, ndhA-intron and ycf1), which are proposed for use as DNA barcode regions. Phylogenetic relationships based on the plastid genomes of 23 species of 14 genera of Urticaceae resulted in the placement of Pilea in the middle and lower part of the phylogenetic tree, with 100% bootstrap support within Urticaceae. Conclusion Our results enrich the resources concerning plastid genomes. Comparative plastome analysis provides insight into the interspecific diversity of the plastid genome of Pilea. The identified hypervariable regions could be used for developing molecular markers applicable in various research areas.

Compared to other G7 countries, Canada performed relatively well after the global financial crisis in both aggregate labour productivity and multifactor productivity (MFP) growth, which is in sharp contrast to its relatively weak performance in the 2000s. The objective of this article is to analyse the sources of Canada’s superior performance by comparing it to other G7 countries. In particular, the article examines industry productivity performance, estimates the contribution of individual industries to both aggregate labour productivity and MFP growth, and highlights the differences between Canada and other G7 countries before and after 2010. To this end, this article develops a methodology to more precisely identify the underlying forces at the industry level that have either propelled or hindered productivity growth, and thereby identify which industries have been at the heart of the changes in productivity performance.

Objective We propose for the first time that D-dimer to creatinine ratio (DCR) may serve as a new clinical biomarker and explore its association with ST-segment elevation myocardial infarction (STEMI). Methods 347 STEMI patients with complete D-dimer and creatinine were included in the analysis. According to the median of DCR value, patients were divided into the lower DCR group (DCR

In this study, sweet-potato-vine-based porous carbon (SPVPC) was prepared using zinc chloride as an activating and pore-forming agent. The optimised SPVPC exhibited abundant porous structures with a high specific surface area of 1397.8 m2 g−1. Moreover, SPVPC exhibited excellent adsorption characteristics for removing methylene blue (MB) from aqueous solutions. The maximum adsorption capacity for MB reached 653.6 mg g−1, and the reusability was satisfactory. The adsorption kinetics and isotherm were in good agreement with the pseudo-second-order kinetics and Langmuir models, respectively. The adsorption mechanism was summarised as the synergistic effects of the hierarchically porous structures in SPVPC and various interactions between SPVPC and MB. Considering its low cost and excellent adsorption performance, the prepared porous carbon is a promising adsorbent candidate for dye wastewater treatment.

Habenaria dentata is a rare species with high ornamental value in China. In this study, we report the complete chloroplast (cp) genome of H. dentata using the Illumina sequencing data. The total genome of H. dentata is 153,682 bp in length and the GC content is 36.62%, with a pair of inverted repeats (IRs) regions of 26,339 bp each, a large single-copy (LSC) region of 83,963 bp and a small single-copy (SSC) region of 17,041 bp. The cp genome encoded 133 genes, including 87 protein-coding genes (PCG), eight rRNA genes, and 38 tRNA genes. The maximum-likelihood phylogenetic analysis based on 12 cp genomes showed that H. dentata was sister to Habenaria chejuensis and Habenaria ciliolaris. This work will be valuable for genetic and phylogenetic studies on H. dentata.

Research and development (R&D) is critical to innovation that enhances productivity. Going beyond a simple relationship between R&D and firm productivity performance, this article investigates what co-investments and other business operating conditions facilitate R&D in improving productivity. Using a rich micro database for Canada, we show that the actual effect of R&D on productivity depends on a number of factors that play important roles in determining R&D efficiency in im-proving productivity. These factors include adopting certain management practices, making investments in ICT, and maintaining a skilled workforce. In addition, the article shows that firm size, foreign ownership and market power are important positive forces in improving R&D efficiency. The findings highlight the complexity of R&D in improving productivity.

The role of hypoxia-regulated long non-coding RNA (lncRNA) in the development of head and neck squamous cell carcinoma (HNSCC) remains to be elucidated. In the current study, we initially screened hypoxia-regulated lncRNA in HNSCC cells by RNA-seq, before focusing on the rarely annotated lncRNA USP2 antisense RNA 1 (USP2-AS1). We determined that USP2-AS1 is a direct target of HIF1α and is remarkably elevated in HNSCC compared with matched normal tissues. Patients with a higher level of USP2-AS1 suffered a poor prognosis. Next, loss- and gain-of-function assays revealed that USP2-AS1 promoted cell proliferation and invasion in vitro and in vivo. Mechanically, RNA pulldown and LC–MS/MS demonstrated that the E3 ligase DDB1- and CUL4-associated factor 13 (DCAF13) is one of the binding partners to USP2-AS1 in HNSCC cells. In addition, we assumed that USP2-AS1 regulates the activity of DCAF13 by targeting its substrate ATR. Moreover, the knockdown of DCAF13 restored the elevated cell proliferation and growth levels achieved by USP2-AS1 overexpression. Altogether, we found that lncRNA USP2-AS1 functions as a HIF1α-regulated oncogenic lncRNA and promotes HNSCC cell proliferation and growth by interacting and modulating the activity of DCAF13.

BackgroundPancreatic cancer (PC) is one of the most lethal human cancers, and radiation therapy (RT) is an important treating option. Many patients diagnosed with PC do not achieve objective responses because of the existence of intrinsic and acquired radioresistance. Therefore, biomarkers, which predict radiotherapy benefit in PC, are eagerly needed to be identified.MethodsWhole-exome sequencing of six pancreatic ductal adenocarcinoma patients (PDAC) (three with a good response and three with a poor response) who had received radical surgery and then radiotherapy has been performed as standard of care treatment. Somatic and germline variants and the mutational signatures were analyzed with bioinformatics tools and public databases. Functional enrichment and pathway-based protein-protein interaction analyses were utilized to address the possibly mechanism in radioresistance. MTT, LDH, and colony formation assay were applied to evaluate cell growth and colony formation ability.ResultsIn the present study, somatic mutations located in 441 genes were detected to be radiosensitivity-related loci. Seventeen genes, including the Smad protein family members (SMAD3 and SMAD4), were identified to influence the radiosensitivity in PDAC. The SMAD3 and SMAD4 genes mutate differently between radiosensitive and radioresistant PDAC patients. Mutation of SMAD3 potentiates the effects of ionizing radiation (IR) on cell growth and colony formation in PDAC cells, whereas mutation of SMAD4 had the opposite effects. SMAD3 and SMAD4 regulate the radiosensitivity of PDAC, at least in part, by P21 and FOXO3a, respectively.ConclusionsThese results indicate that mutations of SMAD3 and SMAD4 likely cause the difference of response to radiotherapy in PDAC, which might be considered as the biomarkers and potential targets for the radiotherapy of pancreatic cancer.

Background and Aims: Studies have shown that dipeptidyl peptidase-4 (DDP-4) inhibitors have anti-atherosclerotic effects. However, in the PROLOGUE study, sitagliptin failed to slow the progression of carotid intima-media thickness (CIMT) relative to conventional therapy. We conducted a post hoc analysis of the PROLOGUE study and compared the effects of sitagliptin and conventional therapy on changes in CIMT in subgroups with or without hyperuricemia. Methods: The PROLOGUE study was a randomized controlled trial of 442 patients with type 2 diabetes mellitus (T2DM). Patients were randomized to receive sitagliptin added therapy or conventional therapy. Based on the serum uric acid levels of all study populations in the PROLOGUE study, we divided them into hyperuricemia subgroup ( n = 104) and non-hyperuricemia subgroup ( n = 331). The primary outcome was changed in carotid intima-media thickness (CIMT) parameters compared with baseline during the 24 months treatment period. Results: In the hyperuricemia subgroup, compared with the conventional therapy group, the changes in the mean internal carotid artery (ICA)-IMT and max ICA-IMT at 24 months were significantly lower in the sitagliptin group [−0.233 mm, 95% confidence interval (CI) (−0.419 to 0.046), p = 0.015 and −0.325 mm, 95% CI (−0.583 to −0.068), p = 0.014], although there was no significant difference in the common carotid artery CIMT. Conclusion: The results of our analysis indicated that sitagliptin attenuated the progression of CIMT than conventional therapy in T2DM and hyperuricemia patients.

We grew three yellow Camellia species (the calcifuge C. nitidissima and C. tunghinensis, and the calcicole C. pubipetala) in acidic and calcareous soils for 7 months and assessed their photosynthetic physiological characteristics, growth performance, and element concentrations in this developmental context. The calcifuge C. nitidissima and C. tunghinensis species exhibited poor growth with leaf chlorosis, growth stagnation, and root disintegration in calcareous soils, and with their Pn, Gs, Tr, Fv/Fm, ΦPSII, ETR, qP, leaf Chla, Chlb, and Chl(a + b) concentrations, and root, stem, leaf, and total biomass being significantly lower when grown in calcareous soils relative to in acidic soils. In contrast, the calcicole C. pubipetala grew well in both acidic and calcareous soils, with few differences in the above parameters between these two soil substrates. The absorption and/or transportation of nutrient elements such as N, K, Ca, Mg, and Fe by the two calcifuge Camellia species plants grown in calcareous soils were restrained. Soil type plays a major role in the failure of the two calcifuge Camellia species to establish themselves in calcareous soils, whereas other factors such as competition and human activity are likely more important limiting factors in the reverse case. This study furthers our understanding of the factors influencing the distribution of these rare and endangered yellow Camellia species, allowing for improved management of these species in conservation projects and horticultural production. [ABSTRACT FROM AUTHOR]

Golden Camellia species are highly specific to certain soil environments. Most species are only native to calcareous soils in karst regions, except for a few that grow only in acidic soils. Our aim is to elucidate the adaptation mechanisms of the species of calcareous-soil golden Camellia (CSC) and acidic-soil golden Camellia (ASC) to habitat soils through plant–soil nutrient characteristics and their relationships. We investigated 30 indices for soils and plants. Compared with ASC, CSC had more fertile soil, while their plant tissues exhibited stronger Ca, P, and Mn and weaker K storage, which may be important mechanisms for adapting to habitat soils. However, ASC showed a higher biological absorption coefficient (BAC) for nutrients, which may contribute to the adaptation of ASC to relatively barren acidic soils. Both CSC and ASC showed much higher BAC and accumulation of Ca than other nutrients. We also found that the concentrations of nutrients in the different tissues varied considerably between species. Correlation analysis revealed 135 significant relationships between the 30 indices, with the soil pH and soil Ca levels being the most important factors influencing the nutrient uptake network. This information helps in understanding the adaptation mechanisms of karst plants to habitat soils.

Abstract Background Camellia nitidissima, a rare and endangered shrub is narrowly distributed in South China and North Vietnam occurring in forest understory. Their light tolerance mechanism is unclear. We measured photosynthesis and related parameters on 2-years-old cuttings growing at 10, 30, 50 and 100% sunlight. Our research question was: At what light level are C. nitidissima cuttings responding most favorably, and what is the eco-physiological basis for their response to light? We hypothesized that as a forest understory growth of C. nitidissima would respond most favorably at low to intermediate light by optimizing photosynthetic activity, and high light will affect photosynthetic functions due to photoinhibition, damage of photosynthetic apparatus and concomitant enzyme activity. Results With increasing light, the maximum net photosynthetic rate (P Nmax) and apparent quantum yield (AQY) decreased, while the light compensation point increased, and light saturation point first increased followed by a decrease. The P Nmax and AQY under 50 and 100% sunlight were significantly lower than that under 10 and 30% sunlight. The chlorophyll fluorescence parameters F m, F v, F v/F m all decreased under high light (> 50%). The contents of chlorophyll a (Chla), chlorophyll b (Chlb), and carotenoid (Car) decreased with increasing light. Relative conductivity, malondialdehyde (MDA) and proline contents in leaves were significantly increased in high light but we found no significant difference in these indices at 10 and 30% sunlight. Conclusions We conclude that C. nitidissima is a shade adapted plant with poor adaptability to high light (> 50%). The novelty of this research is the demonstration of the eco-physiological basis of its light tolerance (conversely, shade adaptation) mechanisms indicated by decreased photosynthetic activity, chlorophyll fluorescence, Chla, Chlb and Car contents and concomitant increase in relative conductivity, MDA and proline contents at high light causing photoinhibition. For artificial propagation of C. nitidissima we recommend growing cuttings below 30% sunlight. For in situ conservation of this valuable, rare and endangered shrub it is necessary to protect its natural habitats.

The prospect of a trade-off between employment growth and productivity growth may create uncertainty among policy makers who strive to create jobs, and at the same time, seek to improve productivity. This article re-visits the issue. It shows that employment growth may be negatively correlated with productivity growth at the industry level. But this is not a trade-off. It is an outcome of market forces in reallocating production resources to rebalance changes in demand and supply conditions of different industries within an economy. At the aggregate level, employment growth may also be negatively correlated with labour productivity growth through its negative influence on capital intensity and labour quality. But, after controlling for those input factors, this article finds that employment growth does not negatively affect multifactor productivity growth.

Sophora japonica cv. jinhuai is the best Chinese Flos Sophorae Immaturus variety with high medicinal and economic values. Generally, Sophora japonica harvests once a year. However, Sophora japonica cv. jinhuai harvests twice a year. This study targeted the flowering mechanisms of Sophora japonica cv. jinhuai by investigating the changes of endogenous hormones in the flower bud differentiation process to explore the important scientific foundation in the production of Sophora japonica cv. jinhuai that harvests twice a year. The contents of indole acetic acid (IAA), gibberellin (GA3), zeatin riboside (ZR), and abscisic acid (ABA) in vegetative period, flower bud stage, budding period, full flowering stage, and fruit stage of flower bud differentiation of Sophora japonica cv. jinhuai were determined by using enzyme-linked immunosorbent assay (ELISA). The hormones' actions of the above different stages were analyzed and compared to each other for further exploring the process of flower bud development (FBD) of Sophora japonica cv. jinhuai. The results showed that, in the process of flower bud differentiation period, from low to high, the endogenous hormones' contents in the first and second harvest times were: ABA > IAA > ZR > GA3. The content of ABA was the highest one among the four endogenous hormones at each stage, which could promote flowering. Low content of IAA might promote flower bud initiation, while GA3 inhibited flower formation. Low level of IAA/ABA ratio (0.374), GA3/ABA ratio (0.073), (IAA+GA3)/ZR ratio (1.887) could promote the transformation of Sophora japonica cv. jinhuai from vegetative growth to reproduction development during flower bud differentiation period. The results provided a solid theoretical basis and technical guarantee for the development of Sophora japonica cv. jinhuai planting industry in northern Guangxi area. [ABSTRACT FROM AUTHOR]

Sophora japonica L. (Faboideae, Leguminosae) is an important traditional Chinese herb with a long history of cultivation. Its flower buds and fruits contain abundant flavonoids, and therefore, the plants are cultivated for the industrial extraction of rutin. Here, we determined the complete nucleotide sequence of the mitochondrial genome of S. japonica 'JinhuaiJ2', the most widely planted variety in Guangxi region of China. The total length of the mtDNA sequence is 484,916 bp, with a GC content of 45.4%. Sophora japonica mtDNA harbors 32 known protein-coding genes, 17 tRNA genes, and three rRNA genes with 17 cis-spliced and five trans-spliced introns disrupting eight protein-coding genes. The gene coding and intron regions, and intergenic spacers account for 7.5%, 5.8% and 86.7% of the genome, respectively. The gene profile of S. japonica mitogenome differs from that of the other Faboideae species by only one or two gene gains or losses. Four of the 17 cis-spliced introns showed distinct length variations in the Faboideae, which could be attributed to the homologous recombination of the short repeats measuring a few bases located precisely at the edges of the putative deletions. This reflects the importance of small repeats in the sequence evolution in Faboideae mitogenomes. Repeated sequences of S. japonica mitogenome are mainly composed of small repeats, with only 20 medium-sized repeats, and one large repeat, adding up to 4% of its mitogenome length. Among the 25 pseudogene fragments detected in the intergenic spacer regions, the two largest ones and their corresponding functional gene copies located in two different sets of medium-sized repeats, point to their origins from homologous recombinations. As we further observed the recombined reads associated with the longest repeats of 2,160 bp with the PacBio long read data set of just 15 × in depth, repeat mediated homologous recombinations may play important role in the mitogenomic evolution of S. japonica. Our study provides insightful knowledge to the genetic background of this important herb species and the mitogenomic evolution in the Faboideae species.

National statistics offices in different countries, as well as individual researchers, make a range of different assumptions and use different approaches to estimating multifactor productivity (MFP) growth. As a result, MFP growth estimates can vary for methodological reasons across countries and for a particular country over a given time period. These methodological choices typically reflect a combination of data availability and the objectives of the study. In this article, we use “reasonably” comparable data for output, labour and capital in Canada and the United States to investigate the sensitivity of MFP growth estimates (by industry and for the business sector in the two countries) to three alternative methodological assumptions. We show that MFP growth estimates for both countries and the Canada-U.S. MFP growth gap are fairly robust to the alternative methodologies and assumptions considered.

Canada's deterioration in labor productivity performance in the post-2000 period, especially relative to the United States, has been a major concern for policy makers. From an industrial structure perspective, this article shows that the faster loss of the manufacturing base in Canada than in the United States and the deterioration in the productivity performance of Canadian large manufacturing firms relative to their US counterparts were the main factors associated with the widening Canada-US labor productivity gap in the post-2000 period. [ABSTRACT FROM AUTHOR]