Proportion of vitamin D deficiency in children/adolescents with type 1 diabetes: a systematic review and meta-analysis.

BACKGROUND: The impact of vitamin D on type 1 diabetes has been a controversial topic in public health. Furthermore, significant differences in the proportion of vitamin D have been noted. The purpose of this systematic review was to determine the overall proportion of vitamin D deficiency in children/adolescents with type 1 diabetes (T1D). METHODS: Based on six electronic databases (PubMed, Web of Science, Embase, Ovid Medline, ProQuest, and Cochrane Library), eligible studies since the databases' inception up to April 2022 were searched. Reference lists were also manually searched to identify additional studies. Overall, studies with statistical information on vitamin D deficiency in children and adolescents with T1D were included, and a random effects model was applied for the meta-analysis. In addition, subgroup and sensitivity analyses were carried out to evaluate heterogeneity, and publication bias was evaluated by using Egger's test. RESULTS: A total of 45 studies involving 6,995 participants met the inclusion criteria; these included 25 countries covering Africa, Oceania, Europe, North America and Asia. The proportion of vitamin D deficiency in children/adolescents with T1D was 45% (95% confidence interval [CI] 37-54%, I2 = 97.94%). Subgroup analysis further revealed that the publication year, study design, vitamin D classification, season and geographical region significantly contributed to the variation in the reported incidence of vitamin D deficiency. CONCLUSIONS: The results of the meta-analysis showed that the proportion of vitamin D deficiency among T1D children/adolescents was 45%. In addition, the proportion remains higher, which has important implications for adapting health and social care systems.

Responsive Alternative Splicing Events of Opisthopappus Species against Salt Stress.

Salt stress profoundly affects plant growth, prompting intricate molecular responses, such as alternative splicing (AS), for environmental adaptation. However, the response of AS events to salt stress in Opisthopappus (Opisthopappus taihangensis and Opisthopappus longilobus) remains unclear, which is a Taihang Mountain cliff-dwelling species. Using RNA-seq data, differentially expressed genes (DEGs) were identified under time and concentration gradients of salt stress. Two types of AS, skipped exon (SE) and mutually exclusive exons (MXE), were found. Differentially alternative splicing (DAS) genes in both species were significantly enriched in "protein phosphorylation", "starch and sucrose metabolism", and "plant hormone signal transduction" pathways. Meanwhile, distinct GO terms and KEGG pathways of DAS occurred between two species. Only a small subset of DAS genes overlapped with DEGs under salt stress. Although both species likely adopted protein phosphorylation to enhance salt stress tolerance, they exhibited distinct responses. The results indicated that the salt stress mechanisms of both Opisthopappus species exhibited similarities and differences in response to salt stress, which suggested that adaptive divergence might have occurred between them. This study initially provides a comprehensive description of salt responsive AS events in Opisthopappus and conveys some insights into the molecular mechanisms behind species tolerance on the Taihang Mountains.

Maintenance of species boundaries amid hybridization in two island gingers with similar ecological niches.

Understanding species boundaries maintenance in the face of hybridization/introgression is an intriguing yet complex topic in evolutionary biology. The underlying mechanisms, however, remain elusive. To address this, we propose to investigate the role of climatic shifts in shaping genetic structure and influencing species boundaries. We combine multilocus genetic data and species distribution modeling to explore how past and current climatic shifts affect the genetic structure and demographic history of two Taiwan endemic gingers, Zingiber pleiostachyum and Z. shuanglongense. We identified a well-delimited genetic structure with evidence of admixture, indicating incomplete reproductive isolation between the two gingers. This is likely due to secondary contact and range overlap during the last glacial maximum, leading to sporadic instances of hybridization. Niche overlap tests based on climate and soil data indicate that these two gingers occupy similar but nonidentical ecological niches. Furthermore, we found that the considerable differences in their current geographic distribution and altitude preferences might have resulted from different seed dispersal capabilities and competitive exclusion due to their similar niche preferences. Our results reveal a model where altitudinal differentiation and dispersal strategy synergistically reinforce the species divergence, thereby illuminating the importance of these factors in shaping and maintaining the island's biodiversity.

Reproductive Biology and Breeding Systems of Two Opisthopappus Endemic and Endangered Species on the Taihang Mountains.

Opisthopappus is a perennial, endemic herb of the Taihang Mountains in China. Two species of this genus (O. longilobus and O. taihangensis) are important wild genetic resources for Asteraceae; however, their reproductive biology has been lacking until now. This study is the first detailed report on the reproductive biology and breeding systems of two Opisthopappus species. Through field observations, the floral syndromes of O. longilobus and O. taihangensis were found to possess a similar pattern, although O. taihangensis has a relatively larger capitulum, more ray ligules, and disc florets. The flowers of both O. longilobus and O. taihangensis are protandrous, a character that can prevent autogamy at the single-flower level, and insects are required for pollination. Further, brightly ligules, brightly bisexual florets, unique fragrance, and amount of nectar suggest that these species propagate via an entomophilous pollination system. Hymenopteran and Diptera species were observed as the effective pollinators for these two species. The outcrossing index, pollen/ovule ratio and the results of hand pollination indicated that these Opisthopappus species might have a mixed mating system that combines cross-fertilization and partial self-fertilization for O. longilobus and O. taihangensis, outcrossing predominated in the breeding system, while self-pollination played an important role in seed production when insect pollination was unavailable, particularly in a harsh environment, such as the Taihang Mountains cliffs. Meanwhile, O. taihangensis might better adapt to severe surroundings with relatively complex floral syndromes, specifically through the attraction of visiting insects and a high seed set rate. The above results not only provide reference information toward a better understanding of the survival strategies of O. longilobus and O. taihangensis in the Taihang Mountains but also lay a solid foundation for further exploring the molecular mechanisms that underly their adaptation under cliff environments.

Study on the Evolution Behavior of Humidity Fields in Cement Concrete Pavements of a Coastal Airport During Early Stages in Humid and Hot Areas.

Airport pavements are prone to early defects during the construction phase, and their early performance during the construction phase is significantly affected by the external temperature field. This article takes the concrete pavement of Xiamen Xiang'an New Airport as an example and uses a three-dimensional (3D) humidity simulation program for cement concrete pavement to study the evolution behavior of the early stage humidity field of the pavement in a humid and hot climate environment. The results indicate that the evolution law of the humidity field of the concrete pavement slab was consistent with the environmental field, presenting a 24 h periodic variation. The environmental field had a significant impact on the humidity of the surface layer of the pavement slab, and the humidity decreased rapidly with time. There was a humidity gradient on both the horizontal plane and the cutting plane of the slab, the horizontal humidity was concentrated from the boundary into the middle of the slab, and the sectional humidity was concentrated from the top to the bottom of the slab. Environmental parameters, construction parameters, and material and structural parameters all influenced humidity through humidity exchange or by changing the saturated vapor pressure inside the slab. The humidity field was most sensitive to environmental humidity and maintenance methods, but less sensitive to material parameters and structural parameters. Through analysis, it is advisable to avoid hot seasons, choose periods of increased environmental humidity, adopt appropriate maintenance methods during construction to reduce humidity stress on the slab, and therefore decrease early stage deterioration and improve service life.

Responses of Aroma Related Metabolic Attributes of Opisthopappus longilobus Flowers to Environmental Changes.

Opisthopappus longilobus (Opisthopappus) and its descendant species, Opisthopappus taihangensis, commonly thrive on the Taihang Mountains of China. Being typical cliff plants, both O. longilobus and O. taihangensis release unique aromatics. To determine the potential differentiation and environmental response patterns, comparative metabolic analysis was performed on O. longilobus wild flower (CLW), O. longilobus transplant flower (CLT), and O. taihangensis wild flower (TH) groups. Significant differences in the metabolic profiles were found, not within O. longilobus, but between O. longilobus and O. taihangensis flowers. Within these metabolites, twenty-eight substances related to the scents were obtained (one alkene, two aldehydes, three esters, eight phenols, three acids, three ketones, three alcohols, and five flavonoids), of which eugenol and chlorogenic were the primary aromatic molecules and enriched in the phenylpropane pathway. Network analysis showed that close relationships occurred among identified aromatic substances. The variation coefficient (CV) of aromatic metabolites in O. longilobus was lower than O. taihangensis. The aromatic related compounds were significantly correlated with the lowest temperatures in October and in December of the sampled sites. The results indicated that phenylpropane, particularly eugenol and chlorogenic, played important roles in the responses of O. longilobus species to environmental changes.

The clinical journey and healthcare resources required for dialysis access of end-stage kidney disease patients during their first year of hemodialysis.

BACKGROUND: Creation and maintenance of dialysis vascular access (VA) is a major component of healthcare resource utilization and cost for patients newly started on hemodialysis (HD). Different VA format arises due to patient acceptance of anticipatory care versus late preparation, and clinical characteristics. This study reviews the clinical journey and resource utilization required for different VA formats in the first year of HD. METHOD: Data of patients newly commenced on HD between July 2015 and June 2016 were reviewed. Patients were grouped by their VA format: (A) pre-emptive surgically created VA (SCVA), (B) tunneled central venous catheter (CVC) followed by SCVA creation, (C) long-term tunneled CVC only. Clinical events, number of investigations and procedures, hospital admissions, and incurred costs of the three groups were compared. RESULTS: In the multivariable analysis, the cost incurred by the group A patients had no significant difference to that incurred in the group B patients (p = 0.08), while the cost of group C is significantly lower (p < 0.001). Both the 62.7% of group A with successful SCVA who avoided tunneled CVC usage, and those with a functionally matured SCVA in group B (66.1%), used fewer healthcare resources and incurred less cost for their access compared to those did not (p = 0.01, p = 0.02, respectively) during the first year of HD. CONCLUSION: With comparable cost, a pre-emptive approach enables avoidance of tunneled CVC. Tunneled CVC only access format incurred lower cost and is suitable for carefully selected patients. Successful maturation of SCVA greatly affects patients' clinical journey and healthcare cost.

Molecular detection and antibiogram of Staphylococcus aureus in rabbits, rabbit handlers, and rabbitry in Terengganu, Malaysia.

OBJECTIVES: This study aims to investigate the prevalence and antibiogram of Staphylococcus aureus and methicillin-resistance S. aureus (MRSA) in rabbits, rabbit handlers, and rabbitry environments in Terengganu. MATERIALS AND METHODS: Swab samples from 183 rabbits (183 oral and 183 ear swabs), 45 rabbit handlers (45 oral and 45 nasal), and environmental (n = 180) samples from rabbitries were collected from 10 rabbit farms in Terengganu. The associated S. aureus isolates from the swabs were isolated using phenotypic microbiology tests. The bacteria were confirmed by polymerase chain reaction targeting nuc (S. aureus) and mecA (MRSA) genes. The antibiogram of all S. aureus isolates was determined using the Kirby-Bauer test. RESULTS: Staphylococcus aureus was detected in 19% of rabbits, 26.7% of rabbit handlers, and 8.8% of swabs from the rabbitry environment. However, MRSA (0%) could not be detected. Antibiotic susceptibility test revealed that S. aureus from rabbits showed low resistance (<20%) against 15 different antibiotics while fully susceptible to 4 antibiotics. Meanwhile, S. aureus from rabbit handlers showed high resistance against penicillin (86%), oxacillin (64%), and amoxicillin (50%). CONCLUSIONS: This study suggests the emergence of antibiotic-resistant S. aureus in rabbit farms settings. Therefore, careful selection of antimicrobial agents will be essential to preserve the effectiveness of treatments toward S. aureus infections.

Evolution of floral characters and biogeography of Heloniadeae (Melanthiaceae): an example of breeding system shifts with inflorescence change.

Heloniadeae (Melanthiaceae) presents an East Asia-North America disjunct distribution. Different molecular and morphological data nevertheless support the tribe as a monophyletic group. However, their phylogenetic relationships and biogeographic history, together with the character evolution, are not clear. Therefore, we constructed a Bayesian phylogenetic tree for Heloniadeae using cpDNA and inferred the historical biogeography and floral character evolution. The results revealed that Heloniadeae was distributed in high-latitudes of East Asia and North America, originating since 22.2 mya. The East Asia clade migrated into southwest China, and subsequently colonized the Korean Peninsula, Taiwan, the Ryukyus, and spread northward to Japan and southern Sakhalin. The evolution of the inflorescence and number of flowers were phylogenetically conserved, associated with the historical biogeography of Heloniadeae. The inflorescences transferred from raceme to sub-umbel, and the number of flowers decreased during the dispersal process, which may be accompanied by changes in the breeding system. Besides, the anthesis period was more affected by the habitat environment than phylogenetic constraints. The flowering temperature of was below 20 °C in most species, except H. kawanoi. Such a low temperature might not be conductive to pollinator activities, but it could be compensated by sustaining seed production with long-lasting flowers.

Environmental Heterogeneity Leads to Spatial Differences in Genetic Diversity and Demographic Structure of Acer caudatifolium.

Under climate fluctuation, species dispersal may be disturbed by terrain and local climate, resulting in uneven spatial-genetic structure. In addition, organisms at different latitudes may be differentially susceptible to climate change. Here, we tracked the seed dispersal of Acer caudatifolium using chloroplast DNA to explore the relationships of terrain and local climate heterogeneity with range shifts and demography in Taiwan. Our results showed that the extant populations have shifted upward and northward to the mountains since the Last Glacial Maximum. The distributional upshift of A. caudatifolium is in contrast to the downward expansion of its closest relative in Taiwan, A. morrisonense. The northern populations of A. caudatifolium have acquired multiple-source chlorotypes and harbor high genetic diversity. However, effective gene flow between the north and south is interrupted by topography, geographic distance, north-south differences in October rainfall, and other climate heterogeneities, blocking southward genetic rescue. In addition, winter monsoon-driven rainfall may cause regional differences in the phenological schedule, resulting in adaptive effects on the timing of range shift and the genetic draft of chlorotype distribution. Terrain, distance, and local climate also differentiate the northernmost populations from the others, supporting the previous taxonomic treatment of Acer kawakamii var. taitonmontanum as an independent variety.

Single-Cell Transcriptome Analysis Decipher New Potential Regulation Mechanism of ACE2 and NPs Signaling Among Heart Failure Patients Infected With SARS-CoV-2.

Aims: COVID-19 patients with comorbidities such as hypertension or heart failure (HF) are associated with poor clinical outcomes. The cellular distribution of Angiotensin-converting enzyme 2 (ACE2), the critical enzyme for SARS-CoV-2 infection, in the human heart is unknown. We explore the underlying mechanism that leads to increased susceptibility to SARS-CoV-2 in patients with cardiovascular diseases and patients of cardiac dysfunction have increased risk of multi-organ injury compared with patients of normal cardiac function. Methods and Results: We analyzed single-cell RNA sequencing (scRNA-seq) data in both normal and failing hearts. The results demonstrated that ACE2 is present in cardiomyocytes (CMs) and non-CMs, while the number of ACE2-postive (ACE2+) CMs and ACE2 gene expression in these CMs are significantly increased in the failing hearts. Interestingly, both brain natriuretic peptides (BNP) and atrial natriuretic peptide (ANP) are significantly up-regulated in the ACE2+ CMs, which is consistent with other studies that ACE2, ANP, and BNP increased in HF patients. We found that genes related to virus entry, virus replication and suppression of interferon-gamma signaling are all up-regulated in failing CMs, and the increase was significantly higher in ACE2+ CMs, suggesting that these CMs may be more vulnerable to virus infection. As the level of expression of both ACE2 and BNP in CMs were up-regulated, we further performed retrospective analysis of the plasma BNP levels and clinical outcomes of 91 COVID-19 patients from a single-center. Patients with higher plasma BNP were associated with significantly higher mortality and expression levels of inflammatory and infective markers. Conclusion: In the failing heart, the upregulation of ACE2 and virus infection associated genes could potentially facilitate SARS-CoV-2 virus entry and replication in these vulnerable cardiomyocyte subsets. COVID-19 patients with higher plasma BNP levels had poorer clinical outcomes. These observations may allude to a potential regulatory association between ACE2 and BNP in mediating myocarditis associated with COVID-19.

Single-cell Transcriptome Analysis Indicates New Potential Regulation Mechanism of ACE2 and NPs signaling among heart failure patients infected with SARS-CoV-2.

BACKGROUND: COVID-19 patients with comorbidities such as hypertension or heart failure (HF) are associated with poor clinical outcomes. Angiotensin-converting enzyme 2 (ACE2), the critical enzyme for SARS-CoV-2 infection, is broadly expressed in many organs including heart. However, the cellular distribution of ACE2 in the human heart, particularly the failing heart is unknown. METHODS: We analyzed single-cell RNA sequencing (scRNA-seq) data in both normal and failing hearts, and characterized the ACE2 gene expression profile in various cell subsets, especially in cardiomyocyte subsets, as well as its interaction with gene networks relating to various defense and immune responses at the single cell level. RESULTS: The results demonstrated that ACE2 is present in cardiomyocytes (CMs), endothelial cells, fibroblasts and smooth muscle cells in the heart, while the number of ACE2-postive (ACE2+) CMs and ACE2 gene expression in these CMs are significantly increased in the failing hearts. Interestingly, both brain natriuretic peptides (BNP) and atrial natriuretic peptide (ANP) are significantly up-regulated in the ACE2+ CMs. Further analysis shows that ANP, BNP and ACE2 may form a negative feedback loop with a group of genes associated with the development of heart failure. To our surprise, we found that genes related to virus entry, virus replication and suppression of interferon-gamma（IFN-γ）signaling are all up-regulated in CMs in failing hearts, and the increases were significantly higher in ACE2+ CMs as compared with ACE2 negative (ACE2-) CMs, suggesting that these ACE2+ CMs may be more vulnerable to virus infection. Since ACE2 expression is correlated with BNP expression, we further performed retrospective analysis of the plasma BNP levels and clinic outcome of 91 COVID-19 patients from a single-center. Patients with higher plasma BNP were associated with significantly higher mortality rate and expression levels of inflammatory and infective markers such as procalcitonin and C-reactive protein. CONCLUSION: In the failing heart, the upregulation of ACE2 and virus infection associated genes, as well as the increased expression of ANP and BNP could facilitate SARS-CoV-2 virus entry and replication in these vulnerable cardiomyocyte subsets. These findings may advance our understanding of the underlying molecular mechanisms of myocarditis associated with COVID-19.

Genetic Divergence and Relationship Among Opisthopappus Species Identified by Development of EST-SSR Markers.

Opisthopappus Shih is an endemic and endangered genus restricted to the Taihang Mountains that has important ornamental and economic value. According to the Flora Reipublicae Popularis Sinicae (FRPS, Chinese version), this genus contains two species (Opisthopappus longilobus and Opisthopappus taihangensis), whereas in the Flora of China (English version) only one species O. taihangensis is present. The interspecific phylogenetic relationship remains unclear and undefined, which might primarily be due to the lack of specific molecular markers for phylogenetic analysis. For this study, 2644 expressed sequence tag-simple sequence repeats (EST-SSRs) from 33,974 unigenes using a de novo transcript assembly of Opisthopappus were identified with a distribution frequency of 7.78% total unigenes. Thereinto, mononucleotides (1200, 45.39%) were the dominant repeat motif, followed by trinucleotides (992, 37.52%), and dinucleotides (410, 15.51%). The most dominant trinucleotide repeat motif was ACC/GGT (207, 20.87%). Based on the identified EST-SSRs, 245 among 1444 designed EST-SSR primers were selected for the development of potential molecular markers. Among these markers, 63 pairs of primers (25.71%) generated clear and reproducible bands with expected sizes. Eventually, 11 primer pairs successfully amplified all individuals from the studied populations. Through the EST-SSR markers, a high level of genetic diversity was detected between Opisthopappus populations. A significant genetic differentiation between the O. longilobus and O. taihangensis populations was found. All studied populations were divided into two clusters by UPGMA, NJ, STRUCTURE, and PCoA. These results fully supported the view of the FRPS, namely, that O. longilobus and O. taihangensis should be regarded as two distinct species. Our study demonstrated that transcriptome sequences, as a valuable tool for the quick and cost-effective development of molecular markers, was helpful toward obtaining comprehensive EST-SSR markers that could contribute to an in-depth assessment of the genetic and phylogenetic relationships between Opisthopappus species.

Stimulation of Hair Growth by Small Molecules that Activate Autophagy.

Hair plays important roles, ranging from the conservation of body heat to the preservation of psychological well-being. Hair loss or alopecia affects millions worldwide, but methods that can be used to regrow hair are lacking. We report that quiescent (telogen) hair follicles can be stimulated to initiate anagen and hair growth by small molecules that activate autophagy, including the metabolites α-ketoglutarate (α-KG) and α-ketobutyrate (α-KB), and the prescription drugs rapamycin and metformin, which impinge on mTOR and AMPK signaling. Stimulation of hair growth by these agents is blocked by specific autophagy inhibitors, suggesting a mechanistic link between autophagy and hair regeneration. Consistently, increased autophagy is detected upon anagen entry during the natural hair follicle cycle, and oral α-KB prevents hair loss in aged mice. Our finding that anagen can be pharmacologically activated in telogen skin when natural anagen-inducing signal(s) are absent has implications for the treatment of hair loss patients.

[Spatial and temporal changes of farmland soil acidification and their influencing factors in different regions of Guangdong Province, Chin]. / å¹¿ä¸œçœä¸åŒåŒºåŸŸå†œç”°åœŸå£¤é ¸åŒ–æ—¶ç©ºå˜åŒ–åŠå ¶å½±å“å› ç´ .

Based on the three datasets from 1980s, 2010 and 2015 in Guangdong Province, we analyzed the spatial and temporal variations of soil pH in farmlands in different regions of Guangdong Province and analyzed the driving factors for such variations. The results showed that the spatial distribution of soil pH in Guangdong Province changed significantly in different periods. During 1980s to 2010, soil pH showed an acidification trend with a decline of 0.3, and increased by 0.09 from 2010 to 2015, with more uneven trend and more obvious acid base differentiation. From the perspective of each region, there was generally a trend of acidification from the 1980s to 2010. From 2010 to 2015, the average pH value of farmland soil in the Pearl River Delta increased by 0.27, while that on the east wing and west wing decreased by 0.05 and 0.15 respectively, showing a unapparent change of soil pH in the mountainous area. Our results showed that soil acidification in diffe-rent areas of Guangdong Province was affected by natural factors such as soil itself and precipitation. In addition, anthropogenic factors such as acid rain, unreasonable fertilization and the planting structure of high-yielding crops were also the main causes of soil acidification. Industrialization, urbanization, mining development, and the spread of soil testing formula fertilization increased soil pH in local areas. Our results could provide theoretical guidance for controlling and alleviating soil acidification and improving the quality of cultivated land in different areas.

Cloning and expression analysis of LoCCD8 during IAA-induced bulbils outgrowth in lily (Oriental Hybrid 'Sorbonne').

Aerial bulbils, which resemble tiny bulbs, develop from axillary buds and facilitate rapid propagation of Lilium. In most species of lily, bulbils are perpetually dormant and little is known about induction of these vegetative structures. Herein, we proposed that strigolactones (SLs) may regulate the induction of bulbils in Lilium. We tested this hypothesis by isolating and investigating the expression patterns of 2 copies of the carotenoid cleavage dioxygenase8 (CCD8) gene in lily-LoCCD8a and LoCCD8b-with regard to biosynthesis of SLs. Expression analyses revealed that LoCCD8a principally is expressed during vegetative growth, whereas LoCCD8b mainly is expressed during reproductive growth. The maximum quantity of LoCCD8a transcripts was observed in the basal plate in most developmental stages, which suggests that SLs may originate from underground parts, especially the basal plate, and move upward. The effects of treatments with indole-3-acetic acid or SL analog (GR24) on outgrowth of bulbils and expression of LoCCD8 genes suggested that SLs function downstream of auxin to inhibit the outgrowth of bulbil. The expression patterns of LoCCD8a and LoCCD8b at sprouting and bulblet weighting stages also implied that SLs may function in nutrient redistribution. Our findings are expected to promote the utilization of bulbils as vegetative propagules for commercial practice.

De novo Assembly and Transcriptome Characterization of Opisthopappus (Asteraceae) for Population Differentiation and Adaption.

Opisthopappus Shih (Asteraceae), an endangered genus endemic to the Taihang Mountains of China, is a high-value ornamental and medicinal plant consisting of two species, Opisthopappus longilobus shih and Opisthopappus taihangensis (Ling) Shih. However, the evolutionary relationships and the taxonomic characteristics between the two species remain unknown. In this study, high-throughput transcriptome sequencing was used to analyze the differential metabolic activity and gene expression and screened special molecular markers for exploring the genetic variation and species differentiation in Opisthopappus Shih. The results showed that 33,974 unigenes with an average size of 801 bp were obtained with optimization of de novo assembly. The comprehensive functional annotation based on Gene Ontology (GO), Cluster of Orthologous Group (COG) and Kyoto Encyclopedia of Genes and Genomes pathway database (KEGG) revealed that these unigenes were mainly related to many physiological, metabolic, and molecular processes. Furthermore, the comparative transcriptome analysis indicated that 3,410 differentially expressed genes were mainly involved in lipid, carbohydrate and amino acid metabolism, xenobiotics biodegradation and metabolism as well as environment adaptation via KEGG. Such as the CYP710A, GST, HSP90A and so on, could be the potential candidate genes for further investigating the molecular mechanism of physiological variations between O. taihangensis and O. longilobus. In addition, the potential 71,804 high quality single nucleotide polymorphisms (SNPs) and 1,444 simple sequence repeats (SSRs) were estimated. Based on the predicted SNP, we have developed eight SNP markers for population genetic analysis in Opisthopappus Shih. A significantly high level of genetic differentiation between the populations of O. longilobus and O. taihangensis were found, and they were clearly grouped into two distinct genetic clusters. These results conformed to the record of Flora Reipublicae Popularis Sinicae (FRPS) and unsupported the taxonomic status in the Flora of China. The transcriptome analysis of Opisthopappus Shih can contribute to in-depth exploring of internal mechanisms in species variation and differentiation based on molecular evidence. With the rich and valuable data resources, the more novel structural, functional, and comparative genomic studies will provide comprehensive insights into the evolutionary relationships between O. taihangensis and O. longilobus.

[Characteristics of Iron Plaque and Its Heavy Metal Enrichment in Typical Mangrove Plants in Shenzhen Bay, China].

Based on the five typical mangrove species in the mangrove wetland of Shenzhen Bay, the contents and distributional characteristics of iron plaques (Fe) and the Mn, Pb, Zn, Cu, As, Cr, Cd, Ni, Co, and Sb enrichment of the iron plaques on mangrove plant roots were investigated. The results show that:① There is a significant difference in the contents of iron plaques among the five mangrove species, and the contents in the species follow the order:Acanthus ilicifolius > Aeagiceras corniculatum > Bruguiera gymnorrhiza > Kandelia obovate > Heritiera littorlis; the content ranged from 0.37 g·kg-1 to 10.81 g·kg-1. ② Iron plaques have a certain enrichment effect on the heavy metals in the sediments. The contents of heavy metals in the iron plaques vary with the plant species, being the highest in A. ilicifolius and the lowest in H. littorlis. This enrichment also varies with the element species:Mn content changed from 0.11 g·kg-1 to 2.67 g·kg-1; the highest contents of Pb, Zn, Cu, As, and Cr changed from 117.44 mg·kg-1 to 189.69 mg·kg-1; and the highest contents of Cd, Ni, Co. and Sb changed from 34.84 mg·kg-1 to 63.34 mg·kg-1. The content of Zn in the iron plaque is negatively correlated with the other heavy metal contents (P<0.001), indicating that Zn might compete with the other elements. ③ Sediment pH significantly affects the content of iron plaque and the accumulation of Mn in the iron plaque (P<0.05). The water content and salinity of the sediments are positively correlated with the contents of heavy metals Cr and Co in the iron plaque (P<0.05). ④ The distribution of iron plaques and their heavy metal contents in different parts of the roots of the mangrove plants follow the order:root tip > root middle > root base.

[Prediction of Distribution of Soil Cd Concentrations in Guangdong Province, China].

Heavy metals are one of the principal soil pollution sources. Contaminated soils affect the quality of agricultural products, and then threaten human health. Prediction of the contaminants distribution in the soil is the foundation of pollution evaluation and risk control. A total of 1000 soil profiles were collected to investigate the spatial variation of soil cadmium (Cd) concentration in Guangdong province. These datasets were divided into two groups, about 900 samples for model training and the other 100 for model validation. Six frequently used GIS spatial interpolation methods including Spline, Natural Neighbor, Ordinary Kriging, Inverse Distance Weighted, Local Polynomial Interpolation and Radial Basis Function, and Cubist which is a type of rule-based model were compared to determine their suitability parameters for estimating soil Cd concentration. Nine different resolutions including 2000, 1500, 1000, 800, 500, 300, 200, 150, and 90 m were selected to calculate, evaluate and compare their accuracy. The results showed that, 1 Quantitative assessment of the continuous surfaces showed that there was a large difference in the accuracy of the seven methods. Cubist was superior to GIS-based spatial interpolation methods at all resolutions. Cubist was the best tool for mapping the spatial distribution of Cd in soils with thirty-seven specific predictors relevant to the source and behavior of Cd (parent material, land use, soil type, soil properties, population density, gross domestic product per capita, and the lengths and classes of the roads surrounding the sampling sites, climatic factors, etc.) at 300 m×300 m resolution. The second was Spline, its accuracy was optimal at the 1500 m×1500 m resolution. 2 Results of Cubist suggested that the soil Cd spatial distribution was primarily dependent on the properties of soil regional parent materials. And soil samples with higher Cd concentration mainly located in Carboniferous and Quaternary areas. 3 Spatially, Cd concentrations were higher in the Pearl River Delta region and north of Guangdong Province. Many hotspots existed throughout the Pearl River Delta region due to transportation and pollution of the river. The major anthropogenic inputs of heavy metals to soils and the environment were metalliferous mining and smelting in the north of Guangdong Province. The soil Cd geometric mean concentration of 0.147 mg·kg-1 was lower than that of China, however it varied from zero to 6.056 mg·kg-1. The areas with soil Cd concentrations greater than 1.0 and 3.0 mg·kg-1 were 160 km2 and 2140 km2 respectively, accounting for 0.09% and 1.18% of the total area of Guangdong Province.