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BACKGROUND Polycyclic aromatic hydrocarbons (PAHs), as a typical persistent organic pollutant, widely exist in the environment and have high stability. Studying of the content distribution and source analysis of PAHs in soil will provide a technical basis for PAHs pollution prevention and control, ecological environment improvement and environmental protection policy-making. OBJECTIVES In order to investigate the content, composition and source of PAHs in the soil environment of different functional areas in Beijing City. METHODS A large-scale sampling was carried out in the core area of Beijing City. At the same time, regional sampling was carried out for different functional areas such as industrial areas, agricultural planting areas, water source protection areas and residential areas. A total of 459 topsoil samples were collected, and the monomer contents of 16 PAHs were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS The average values of the total contents of 16 PAHs (∑16PAHs) in topsoil of the three subregions in the core area (southeast, center and northwest) were 153.7, 333.2 and 142.9μg/kg, respectively. The average values of ∑16PAHs in topsoil of the industrial zone, including Southeast Factory, Shougang Industry and Datai Coal Mine, were 1006.9, 1379.4 and 146.8μg/kg, respectively. The average values of ∑16PAHs in topsoil of the water-conserving areas, Huairou and Miyun, were 86.4μg/kg and 154.5μg/kg, respectively. The average values of ∑16PAHs in topsoil of four agricultural planting regions (Changping, Pinggu, Fangshan and Tongzhou) were 109.0, 118.3, 106.8 and 94.2μg/kg, respectively. The average value of ∑16PAHs in topsoil of residential areas was 131.1μg/kg. Compared with previous research results on the content and distribution characteristics of PAHs, the content of PAHs in the topsoil in Beijing City showed a decreased trend, which was related to the decrease in the use of coal and the increase in the use of natural gas in Beijing City in recent years. The composition of PAHs in different functional areas was different. The proportion of heavy and medium rings PAHs were higher in industrial areas. The proportion of light rings PAHs in water-conserving areas, agricultural planting regions and residential areas was higher than that in industrial areas, which might be due to the different sources of PAHs in different functional areas. The results of principal component analysis-multiple linear regression method showed that the main sources of PAHs in the core area were tail gas emissions and leakage during oil storage and transportation, which contributed 81.46% and 18.54%, respectively. The main sources of PAHs in the topsoil of the industrial area were coal combustion and tail gas emissions, which contributed 62.65% and 37.35%, respectively. The main sources of PAHs in residential areas were tail gas emissions and natural gas combustion sources, with contribution rates of 53.30% and 46.70%, respectively. CONCLUSIONS Further strengthening traffic control, continuing to reduce the proportion of coal in energy structure, and increasing the proportion of clean energy are effective ways to reduce PAHs emissions and pollution in Beijing City.

BACKGROUND The groundwater in Xingguo County is rich in metasilicic acid, but the research on the endowment characteristics and genetic mechanism of mineral water resources is relatively weak, which restricts the development of the mineral water industry in Xingguo County to some extent. Research on the chemical characteristics and health functions of metasilicate mineral water in the county provides basic support for the development of the local mineral water industry and the implementation of a revitalization strategy. OBJECTIVES To summarize the distribution characteristics of metasilicate mineral water in Xingguo County and evaluate its health function. METHODS Mathematical statistics, water chemistry analysis, ion ratio and other analytical methods were used to study the distribution, water chemistry characteristics, genesis and material sources of potential metasilicate mineral water in Xingguo County, and its health function based on sensory index and health index was evaluated. RESULTS Potential metasilicate mineral water was mainly distributed in the area below 400m above sea level, and it was distributed primarily in a magmatic rock fissure water-bearing rock formation, a clastic rock pore fissure water-bearing rock formation and a metamorphic rock fissure water-bearing rock formation. In the investigated water samples of these three types of water-bearing rock formations, the proportion of potential metasilicate mineral water was 48.5%, 45.7% and 29.6%, respectively. The metasilicic acid content of potential metasilicate mineral water was mostly between 32 and 40mg/L, mainly from the hydrolysis of silicate minerals. The enrichment of metasilicic acid was caused by solution filtration in the metamorphic rock and magmatic rock fracture water-bearing formation area, and was jointly affected by solution filtration and cation alternating adsorption in the clastic rock pore fracture water-bearing formation area. The potential metasilicate mineral water in the magmatic rock fracture water-bearing group area had the best taste, and the deep clastic rock pore water bearing group area had a relatively high health index. CONCLUSIONS The results of this study suggest that the target area of mineral water exploration and development in Xingguo County should be in magmatic rock fissure water-bearing rock formation areas and deep clastic rock pore fissure water-bearing rock formation areas. The research results provide reference for revealing the value and function of metasilicate mineral water resources in Xingguo County.

A mathematical model of particle growth taking nonlinear temperature-depended interface kinetics into account was investigated,and the particle interface evolution and morphological stability were analyzed. The asymptotic solution of particle growth and the change rate of interface perturbations were obtained by means of an asymptotic expansion method. The result shows that the interface kinetics undercooling and the particle growth velocity decrease with increasing interface kinetics,and that the nonlinear temperature-depended interface kinetics tends to stabilize particle growth. Compared with the situation of neglecting interfacial kinetics,the nonlinear interfacial kinetics significantly decreases the particle growth velocity.

Abstract Background Invasive ductal carcinoma (IDC) of the breast usually metastasizes to the lungs, liver, bones and brain. Solitary adrenal metastasis is extremely rare. Due to the rarity of this condition, the optimal treatment is unclear. We report the first case of IDC of the breast metastasizing solely to the adrenal gland after a modified radical mastectomy but having a long-term disease-free survival while treated merely by a left adrenalectomy. Case presentation A 64-year-old woman was found a left adrenal mass on a follow- up visit two years after taking a right modified radical mastectomy for the breast cancer. She was subsequently given a left adrenalectomy. Postoperative histopathology findings were compatible with invasive ductal carcinoma (IDC) of the breast. Due to the patient's refusal, no further treatments were offered after the adrenalectomy. The patient now is still alive and has no sign of relapse. Survival time after taking the right modified radical mastectomy and the left adrenalectomy is more than five years and three years, respectively. Conclusion This is the first case of a patient with solitary, metachronous adrenal metastasis from IDC of the breast to be reported. For patients in this condition, complete removal of metastasized organ may translate into survival benefit.

The synthesis of a (phosphino)(stannyl)carbene is documented. The combination of phosphino and stannyl substituents imparts a highly ambiphilic nature to this carbene, enabling reactions with cyanide, isocyanide, and carbon monoxide. This leads to rare stannylketenimines and a stannylketene. [ABSTRACT FROM AUTHOR]

Elucidating how plant species respond to variable light conditions is essential to understanding the ecological adaptation to heterogeneous environments. Plant performance and gene regulatory network underpinning the adaptation have been well documented in heliophytic species. However, it remains largely unclear how the sciophytic plants respond to distinct light conditions. We measured phenotypic and transcriptomic features of four sciophytic (Fatsia japonica, Metapanax delavayi, Heptapleurum arboricola, and Heptapleurum delavayi) and one heliophytic woody species (Tetrapanax papyrifer) of the Araliaceae family under distinct light conditions. Our phenotypic comparisons demonstrate that the four sciophytic species maintain similar photosynthesis efficiency between high light and low light conditions. However, a significantly decreased photosynthesis rate was observed under the low light conditions of the heliophytic species compared with the high light conditions. In addition, our leaf anatomical analyses revealed that, while all five species showed different anatomical structures under distinct light conditions, the sciophytic species possessed a lower degree of phenotypic plasticity relative to the heliophytic species. Further comparisons of the transcriptome profiling showed that differentially expressed genes identified in the five species were functionally related to photosynthesis, secondary metabolites, and other basic metabolisms. In particular, differential regulation of the photosynthesis‐related and photomorphogenesis‐related genes were potentially correlated with the phenotypic responses to the distinct light conditions of the five species. Our study provides evolutionary and ecological perspectives on how the heliophytic and sciophytic woody species respond to shade and sunlight environments. [ABSTRACT FROM AUTHOR]

Phosphaborenes, featuring a phosphorus‐boron multiple bond, remain a relatively untapped area in chemical research due to the limited synthetic methods. Introducing leaving groups as substituents to the phosphorus or boron can pave the way for enhanced functionalization and modification. In this study, we present the synthesis of phosphaborenes featuring an N‐heterocyclic boryl group on phosphorus and halogen substituent on boron, with stabilization provided by an N‐heterocyclic carbene. Straightforward alkylation/arylation of these phosphaborenes is achieved by substituting the halogen with benzyl and aryl groups at the boron terminus. Our approach offers an efficient route to produce a diverse array of phosphaborene structures. [ABSTRACT FROM AUTHOR]

SUMMARY: Understanding how different driving forces have promoted biological divergence and speciation is one of the central issues in evolutionary biology. The Triticum/Aegilops species complex contains 13 diploid species belonging to the A‐, B‐ and D‐lineages and offers an ideal system to address the evolutionary dynamics of lineage fusion and splitting. Here, we sequenced the whole genomes of one S‐genome species (Aegilops speltoides) of the B‐lineage and four S*‐genome diploid species (Aegilops bicornis, Aegilops longissima, Aegilops sharonensis and Aegilops searsii) of the D‐lineage at the population level. We performed detailed comparisons of the five species and with the other four representative A‐, B‐ and D‐lineage species. Our estimates identified frequent genetic introgressions from A‐ and B‐lineages to the D‐lineage species. A remarkable observation is the contrasting distributions of putative introgressed loci by the A‐ and B‐lineages along all the seven chromosomes to the extant D‐lineage species. These genetic introgressions resulted in high levels of genetic divergence at centromeric regions between Ae. speltoides (B‐lineage) and the other four S*‐genome diploid species (D‐lineage), while natural selection is a potential contributor to divergence among the four S*‐genome species at telomeric regions. Our study provides a genome‐wide view on how genetic introgression and natural selection acted together yet chromosome‐regionally divided to promote genomic divergence among the five S‐ and S*‐genome diploid species, which provides new and nuanced insights into the evolutionary history of the Triticum/Aegilops species complex. Significance Statement: The S‐ and S*‐genome section of genus Aegilops has long been considered as the close relatives to B‐subgenome of common wheat (Triticum aestivum). Here we showed that post‐hybridization introgression and natural selection have determined the heterogeneous pattern of genomic divergence of the five species. Given that all the five species can be crossed with polyploid wheat, our new findings, together with the newly generated genome resources, will facilitate exploitation of the S‐ and S*‐genome species in wheat improvement. [ABSTRACT FROM AUTHOR]