Next-generation sequencing through multi-gene panel testing for diagnosis of hereditary ichthyosis in Chinese.

Inherited ichthyoses are a heterogeneous group of rare disorders related to over 40 genes. To identify underlying molecular causes in inherited ichthyosis among Chinese and to correlate genotype and phenotype, 35 probands clinically diagnosed inherited ichthyosis, except ichthyosis vulgaris and X-linked ichthyosis, were included in our study. Molecular analysis was performed using next-generation sequencing (NGS) through multi-gene panel testing targeting all ichthyosis-related genes. Genetic variants causative for the ichthyosis were identified in 32 of 35 investigated patients. In all, 43 causative mutations across 12 genes were disclosed, including 16 novel variants. Thirteen keratinopathic ichthyosis, fourteen autosomal recessive congenital ichthyosis (ARCI) including one caused by mutations in SDR9C7, and five syndromic ichthyoses were confirmed. Four probands, with presumptive ARCI, turned out to be keratinopathic ichthyosis (2), neutral lipid storage disease (1), and Sjogren-Larsson syndrome (1), respectively. Next-generation technology has been demonstrated to be an effective tool in diagnosing inherited ichthyosis constituting a diverse group of cornification disorders. Our study further expands mutation spectrum and clinical phenotype associated with inherited ichthyosis in Chinese.

Clinical and molecular characteristics of thirty NF1 variants in Chinese patients with neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1) is a common autosomal dominant tumor-predisposition disorder that mainly impacts the nervous system and skin. Since the full clinical presentation of NF1 depends on age, it can be difficult to make an early and definite diagnosis in paediatric patients without family history who only exhibited multiple cafè-au-lait spots, highlighting the need for mutational analysis. A combination of techniques was conducted in 30 families with NF1, including multi-gene panels, direct sequencing, cDNA sequencing and multiplex ligation-dependent probe amplification. Thirty variants were identified in 36 patients from the 30 families, among which ten variants were novel. As a result, we confirmed that the combination of techniques were highly accurate and sensitive for identifying pathogenic variants in patients clinically suspected of having NF1, in particular, for patients who only present with multiple cafè-au-lait spots.

Distribution, sources, and toxicity assessment of polycyclic aromatic hydrocarbons in surface soils of a heavy industrial city, Liuzhou, China.

As a heavy industrial city, Liuzhou has been facing a serious pollution problem. It is necessary to take steps to control and prevent environmental pollution wherever possible. Surface soil samples were collected from four communities in Liuzhou City, to determine the concentrations, distributions, sources, and toxicity potential of polycyclic aromatic hydrocarbons (PAHs) present. The mean concentrations of total PAHs in the surface soil are 756.43 ng/g for the heavy industrial area, 605.06 ng/g for the industrial area, 481.24 ng/g for the commercial-cum-residential area, and 49.93 ng/g for the rural area. Both the isomer ratio and principal component analyses for the PAHs prove that these pollutants originate mainly from coal, diesel, gasoline, and natural gas combustion. The pollution hierarchies and toxic equivalency factor of BaP prove that the city is subject to heavy pollution caused by industry, transportation, and daily human activities.

Heterogeneous nucleation induced A. pernyi/B. mori silk fibroin coatings on AZ31 biometals with enhanced corrosion resistance, adhesion and biocompatibility.

Silk fibroin coatings on biomedical magnesium alloys have garnered significant attention due to their enhanced corrosion resistance and biocompatibility. However, the utilization of wild A. pernyi silk fibroin, known for its RGD sequence that facilitates tissue regeneration, presents a challenge for corrosion-resistant coatings on magnesium alloys due to its weak adhesion and high dissolution rate. In this study, we employed hexafluoroisopropanol as a solvent to blend A. pernyi silk fibroin with B. mori silk fibroin. The resulting blended fibroin coating at a 3:7 mass ratio exhibited a heterogeneous nucleation effect, enhancing ß-sheet content (32.3 %) and crystallinity (28.6 %). This improved ß-sheet promoted the "labyrinth effect" with an Icorr of 2.15 × 10-6 A cm-2, resulting in significantly improved corrosion resistance, which is two orders of magnitude lower than that of pure magnesium alloy. Meanwhile, the increased content of exposed serine in zigzag ß-sheet contributes to a higher adhesion strength. Cell cytotoxicity evaluation confirmed the enhanced cell adhesion and bioactivity. This work provides a facile approach for wild A. pernyi silk fibroin coatings on magnesium alloys with enhanced corrosion resistance, adhesion and biocompatibility.

[Pollution Characteristics of Organochlorine Pesticides in Water and Sediments of Huixian Karst Wetland in Guilin].

Karst wetland plays an important role in the ecological environment; however, due to the existence of karst pipeline, pollutants can threaten the underground environment through the highly developed karst pipeline. Therefore, understanding the pollution characteristics of the karst surface environment is the premise of pollution ecological risk assessment and prevention. In this study, 24 organochlorine pesticides (OCPs) were analyzed to study the concentration, composition, source, and risk of OCPs in water and surface sediments in the Huixian Wetland of Guilin. The results showed that:the concentration of OCPs in water ranged from 3.17 ng·L-1 to 92.50 ng·L-1, and the concentration of OCPs in sediment ranged from 1.16 ng·g-1 to 219.52 ng·g-1, showing the main pollution characteristics of HCHs and DDTs. The concentration of OCPs in water was higher in the wet season than that in the dry season. The concentration of OCPs in sediments was higher in the dry season than that in the wet season. The isomer ratios revealed that OCPs in the study area were mainly derived from long-term degradation residues, and some sites had new input of lindane. Based on Monte Carlo simulation, the human health risk assessment of the study area showed that the 95% quantile carcinogenic risk of OCPs in water was greater than 1×10-6, with potential but acceptable health risk. The non-carcinogenic risk was lower than 1, which indicated that the level of OCPs residues in the water in the study area was not enough to cause non-carcinogenic risk to the human body.

Ballistic Limit of UHMWPE Composite Armor under Impact of Ogive-Nose Projectile.

The ballistic response of armor has been widely used to evaluate its feasibility and advantages as a protective structure. To obtain the ballistic performance and ballistic limitations of composite armor, a type of ultra-high molecular weight polyethylene (UHMWPE) composite armor is designed, which is composed of UHMWPE laminates and steel face sheets of Q235. The total thickness of the armor is 53 mm, with an in-plane dimension of 300 mm × 300 mm. Then, an experimental study of the ballistic impact response of composite armor subject to a typical ogive-nose projectile was carried out. In the velocity range of 501.1 to 1026.1 m/s, the 14.5 mm caliber armor-piercing projectile could penetrate through the composite armor. At the velocity of 433.3 m/s, the A-P projectile was embedded in the armor, leaving a bulge mark on the back sheet. Therefore, 467.2 m/s is taken as the ballistic limit of the armor under the impact of the ogive-nose projectile. In addition, a corresponding numerical simulation model is also established to predict the ballistic limit of the projectile. The numerical predictions are consistent with the experimental results. The ballistic limit obtained from the numerical simulation results is 500 m/s, which is acceptable with a relative error of 7.02%. The failure mechanism of the composite armor is also obtained. Petaling is the main dominant failure mode for both face sheets, while delamination and shear failure dominate the penetration process of UHMWPE laminates. Finally, the perforation mechanism of composite armor under the impact of an A-P projectile is analyzed with theoretical models to predict the residual velocity, the work performed during the perforation, and the resisting stress of σs in the cavity-expansion model. The experimental and numerical simulation results can provide necessary data in the analysis of the composite structure's dynamic response under the impact of sharp head penetrators. The research results present the ballistic performance, failure mechanism, and ballistic limit of the composite armor under the impact of a typical ogive-nose projectile, which can be significant in the design of composite armor in the areas of ship shield, fortifications protection, and bulletproof structures against threats from sharp head penetrators.

Dynamic Response of UHMW-PE Composite Armors under Ballistic Impact of Blunt Projectiles.

To study the dynamic response of UHMW-PE composite armor under ballistic impact, two kinds of UHMW-PE composite armors are designed. Both of them are composed of UHMW-PE laminates and steel face sheets of Q235. The blunt projectile is made of 35CrMnSiA, with a cylinder shape. By numerical simulation, the dynamic response and deformation of composite armors are obtained under the penetration of the projectile. With the increase of impact velocity, the penetration depth increases nearly linearly, with a more severe tendency of swaging in the projectile. Then, experiments are carried out to validate the numerical simulation results. Based on a ballistic gun with a caliber of 14.5 mm, the projectiles are fired with a velocity from 680 m/s to 1300 m/s. The penetration into the composite armor can be divided into an initial shear plugging stage and the following bulging and delamination stage. Based on the theoretical analysis, the shear strength in the shear plugging stage can be estimated. Associated with typical experimental results, numerical simulation is suitable to predict the bulging characteristics of the composite armor. The failure mode of the composite armors under the impact of blunt projectiles is determined, and the failure mechanism is analyzed. The penetration results in the experiment agree well with the numerical simulation results, which validate the correctness of the numerical simulation models. The research results can be significant in the design of composite armor with UHMW-PE laminates.

Case Report: Chanarin-Dorfman Syndrome: A Novel Homozygous Mutation in ABHD5 Gene in a Chinese Case and Genotype-Phenotype Correlation Analysis.

The Chanarin-Dorfman syndrome (CDS) is a rare, autosomal recessively inherited genetic disease, whch is associated with a decrease in the lipolysis activity in multiple tissue cells. The clinical phenotype involves multiple organs and systems, including liver, eyes, ears, skeletal muscle and central nervous system. Mutations in ABHD5/CGI58 gene have been confirmed to be associated with CDS. We performed whole exome sequencing on a Chinese CDS patient with skin ichthyosis features mimicking lamellar ichthyosis, ectropion, sensorineural hearing loss, and lipid storage in peripheral blood neutrophils. A novel homozygous missense mutation (p.L154R) in ABHD5 gene was detected in this patient. Genotype-phenotype analysis in reported CDS patients revealed no particular correlation. Our findings further enrich the reservoir of ABHD5 mutations in CDS.

Concentration and Spatial Distribution of Potentially Toxic Elements in Surface Soil of a Peak-Cluster Depression, Babao Town, Yunnan Province, China.

Potentially toxic elements (PTEs) in Chinese agricultural soils, including those in some heritage protection zones, are serious and threaten food safety. Many scientists think that these PTEs may come from parent rock. Hence, at a karst rice-growing agricultural heritage area, Babao town, Guangnan County, Yunnan Province, China, the concentrations of eight PTEs (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) were determined in 148 surface soil, 25 rock, and 52 rice grain samples. A principal component analysis (PCA) and hierarchical cluster analysis were used to divide the surface soil into groups, and inverse distance weighting (IDW) was used to analyze the spatial distribution of PTEs. Soil pollution was assessed with the geoaccumulation index (Igeo). The results show that Cd, Hg, Zn, and Cr were polluting the soil (average Igeo > 0). The highest concentration of PTEs was distributed in the southwest of Babao town in the carbonate rock area, which had the highest pH and soil total organic carbon (Corg), Mn, and TFe2O3 contents. PCA biplots of soil samples showed that the carbonate rock area was associated with the most species of PTEs in the study area including Pb, Cd, Hg, As, and Zn. The clastic rock area was associated with Cu and Ni, and the lime and cement plants were associated with CaO, pH, Corg, TC, and aggravated PTE pollution around factories. In high-level PTE areas, rice was planted. Two out of 52 rice grain samples contained Cd and 4 out of 52 rice grain samples had Cr concentrations above the Chinese food safety standard pollutant limit (Cd 0.2 mg/kg; Cr 1 mg/kg). Therefore, the PTEs from parent rocks are already threatening rice safety. The government should therefore plan rice cultivation areas accordingly.

A Contextual Fire Detection Algorithm for Simulated HJ-1B Imagery.

The HJ-1B satellite, which was launched on September 6, 2008, is one of the small ones placed in the constellation for disaster prediction and monitoring. HJ-1B imagery was simulated in this paper, which contains fires of various sizes and temperatures in a wide range of terrestrial biomes and climates, including RED, NIR, MIR and TIR channels. Based on the MODIS version 4 contextual algorithm and the characteristics of HJ-1B sensor, a contextual fire detection algorithm was proposed and tested using simulated HJ-1B data. It was evaluated by the probability of fire detection and false alarm as functions of fire temperature and fire area. Results indicate that when the simulated fire area is larger than 45 m(2) and the simulated fire temperature is larger than 800 K, the algorithm has a higher probability of detection. But if the simulated fire area is smaller than 10 m(2), only when the simulated fire temperature is larger than 900 K, may the fire be detected. For fire areas about 100 m(2), the proposed algorithm has a higher detection probability than that of the MODIS product. Finally, the omission and commission error were evaluated which are important factors to affect the performance of this algorithm. It has been demonstrated that HJ-1B satellite data are much sensitive to smaller and cooler fires than MODIS or AVHRR data and the improved capabilities of HJ-1B data will offer a fine opportunity for the fire detection.

[Concentration Characteristics, Source Analysis, and Potential Ecological Risk Assessment of Heavy Metals in a Peak-cluster Depression Area, Southeast of Yunnan Province].

The pollution characteristics, sources, and ecological risk of heavy metals in farmland soils were studied in a peak-cluster depression area southeast of Yunnan Province. In total, 199 topsoil samples were collected using the grid method and contents of eight heavy metals (As, Cd, Cr, Cu, Pb, Ni, Zn, and Hg) were determined. The geoaccumulation index and potential ecological risk index (RI) were used to evaluate soil pollution levels and potential ecological risks, respectively. The absolute principal component scores-multivariate linear regression (APCS-MLR) model and cluster analysis were used to identify the pollution sources and apportion the heavy metals in the soils. The results show that the mean content of Cd, Hg, Cr, Ni, and Zn was higher than their respective background values, exceeding them by up to 16.00, 7.29, 1.46, 1.45, and 2.39 times, respectively. No evidence of the occurrence of other metals was found. The average RI was 1039.3, which represents a high potential ecological risk, with Cd and Hg being the most crucial elements. The APCS-MLR model revealed that natural sources (PC1), traffic sources (PC2), fossil fuel combustion sources (PC3), and agricultural sources (PC4) were the four main contributors of soil heavy metals. The primary source of Cd, Cr, and Ni was PC1, while PC2 was the main source of Pb and Zn. PC3 and PC4 were the main sources of Cu and Hg with contribution rates of 77.86% and 70.37%, respectively. The main sources of As were PC1 (46.71%) and PC4 (49.46%).

[Distribution and Sources of Polycyclic Aromatic Hydrocarbons in a Karst Groundwater System in a Strongly Industrial City].

To understand the spatiotemporal variation characteristics and sources of polycyclic aromatic hydrocarbons in karst groundwater in a strongly industrial city, the authors collected 23 groundwater samples in the water and dry period in Liuzhou using component spectra of 16 types of polycyclic aromatic hydrocarbons in combination with the physical and chemical properties and analyzed the spatiotemporal variation characteristics and sources of the polycyclic aromatic hydrocarbons (PAHs) in karst groundwater in heavy industrial city. The results show that the average concentration of ∑PAHs in the groundwater in the wet period has an order of Liubei District > Liudong District > Liuxi District > Jila Underground River and the concentration proportion of PAHs decreases with the increase of the molecular weight, while the order in the dry period is Jila Underground River > Liubei District > Liuxi District > Liudong District. The PAHs in the groundwater during the dry season have a high pollution level, while a low pollution level is observed in the wet season. The main sources of PAHs are organic matter burns at high temperature such as fossil fuel, which are produced by human activities such as industrial processes, transportation, heating, and cooking.

Identification of Differentially Expressed Genes and Signaling Pathways in Acute Myocardial Infarction Based on Integrated Bioinformatics Analysis.

BACKGROUND: Acute myocardial infarction (AMI) is a common disease with high morbidity and mortality around the world. The aim of this research was to determine the differentially expressed genes (DEGs), which may serve as potential therapeutic targets or new biomarkers in AMI. METHODS: From the Gene Expression Omnibus (GEO) database, three gene expression profiles (GSE775, GSE19322, and GSE97494) were downloaded. To identify the DEGs, integrated bioinformatics analysis and robust rank aggregation (RRA) method were applied. These DEGs were performed through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses by using Clusterprofiler package. In order to explore the correlation between these DEGs, the interaction network of protein-protein internet (PPI) was constructed using the STRING database. Utilizing the MCODE plug-in of Cytoscape, the module analysis was performed. Utilizing the cytoHubba plug-in, the hub genes were screened out. RESULTS: 57 DEGs in total were identified, including 2 down- and 55 upregulated genes. These DEGs were mainly enriched in cytokine-cytokine receptor interaction, chemokine signaling pathway, TNF signaling pathway, and so on. The module analysis filtered out 18 key genes, including Cxcl5, Arg1, Cxcl1, Spp1, Selp, Ptx3, Tnfaip6, Mmp8, Serpine1, Ptgs2, Il6, Il1r2, Il1b, Ccl3, Ccr1, Hmox1, Cxcl2, and Ccl2. Ccr1 was the most fundamental gene in PPI network. 4 hub genes in total were identified, including Cxcl1, Cxcl2, Cxcl5, and Mmp8. CONCLUSION: This study may provide credible molecular biomarkers in terms of screening, diagnosis, and prognosis for AMI. Meanwhile, it also serves as a basis for exploring new therapeutic target for AMI.

Coinheritance of generalized pustular psoriasis and familial Behçet-like autoinflammatory syndrome with variants in IL36RN and TNFAIP3 in the heterozygous state.

Generalized pustular psoriasis (GPP) is now known to be caused by biallelic variants in IL36RN and monoallelic variants in CARD14 and AP1S3. The presence of a modifier locus or oligogenic inheritance have been hypothesized. We report on a patient with a unique coinheritance of pathogenic variants in IL36RN (c.115+6T>C) and TNFAIP3 (c.547C>T, p.R183*) causing the genetic entities GPP and familial Behçet-like autoinflammatory syndrome (AISBL). The heterozygous variant in IL36RN identified by Sanger sequencing was inherited from his unaffected father, while the heterozygous variant in TNFAIP3 was detected by whole-exome sequencing and was also identified in the patient's AISBL-affected maternal relatives. Further functional studies are required to research whether the variant of TNFAIP3 plays a part in the development of GPP or simply causes the Behçet's disease phenotype. However, our data suggest that whole-exome sequencing for the heterozygous carrier of the IL36RN gene in GPP be used to find the potential second genetic locus.

[Distribution Characteristics of Polycyclic Aromatic Hydrocarbons in Environmental Media in Nanning City].

In order to understand the contamination characteristics of polycyclic aromatic hydrocarbons in different environmental media, the authors collected samples of air, atmospheric dry and wet depositions, soil and groundwater in winter and summer in Nanning, using component spectra of 16 kinds of polycyclic aromatic hydrocarbons, combining with the physical and chemical properties, analyzed concentration, composition and distribution characteristics of the PAHs in different environment media, the results showed that PAHs with 2 to 3 rings were dominant in the air and atmospheric dry and wet depositions, and ∑ PAHs in winter were higher than in summer because of the seasonal differences. And PAHs with 2 to 3 rings were dominant in soil, too. Distribution difference of soil particle diameter was the main reason for the PAHs distribution characteristics in different horizons. And species of PAHs in groundwater were fewer, with lower concentrations, which showed that soil vadose zone could entrap more PAHs. The mass fraction of 16 kinds of polycyclic aromatic hydrocarbons in different environmental media presented a decreasing trend from low rings to high rings, and the distribution characteristics of PAHs with 2 to 3 rings and 5 to 6 rings in different environmental media in two areas in winter and summer had good consistency, but also had certain differences because of the physical and chemical properties of PAHs, hydro-geological conditions, urban pollution, weather conditions, etc.

[Isolation and identification of mosquito-borne arboviruses in Yuncheng city, Shanxi province, 2012].

OBJECTIVE: To investigate the species and distribution of mosquitoes and mosquito-borne arboviruses in Yuncheng city of Shanxi province, China. METHODS: Mosquito samples were collected in 19 collection sites from Linyi county and Yongji city in Yuncheng city, in August, 2012. After identification and classification, all the specimens were homogenized and centrifuged to acquire supernatant before being inoculated to both C6/36 and BHK21 cells for viral isolation. Positive isolates were identified with arbovirus species-specific primers under RT-PCR, for further sequencing and phylogenetic analysis. RESULTS: A total of 10 455 mosquitoes of 7 species in 4 genuese were collected. The predominant mosquito species in Linyi county was Culex pipens pallens (91.96%, 3 911/4 253), but the one in Yongji city was Culex tritaeniorhynchus (72.85%, 4 518/6 202). A total of 23 strains of viruses were isolated from the mosquito pools. 15 strains from Culex tritaeniorhynchus and Culex pipens pallens were identified as genotype I Japanese encephalitis virus (JEV). Four strains from Culex pipens pallens were identified as Culex flavivirus (CxFV). Three strains from Culex pipens pallens were identified as Culex pipiens pallens densovirus (CppDNV). One strain from Armigeres subalbatus and Aedes albopictus was identified as Getah virus (GETV). CONCLUSION: Four kinds of arboviruses were isolated from the mosquito pools, including GETV and CxFV, which were isolated and documented in Shanxi province for the first time. In the city of Yuncheng, Culex tritaeniorhynchus had been the predominant species and major vector for transmitting JEV. Genotype I JEV remained the major JEV circulating in the local natural environment.

[Transport and differentiation of polycyclic aromatic hydrocarbons in air from Dashiwei karst Sinkholes in Guangxi, China].

The typical karst Dashiwei Sinkholes located in Leye County, Guangxi were chosen as the study object. The air samples from the opening of Dashiwei Sinkholes to the underground river profiles were collected by polyurethane foam passive samplers (PUF-PAS), and the meteorological parameters were observed. The 16 PAHs were analyzed using GC-MS. The results showed that the total PAHs concentration in air in Dashiwei Sinkholes ranged from 33.76 ng x d(-1) to 150.86 ng x d(-1), with an average of 80.36 ng x d(-1). The mean concentrations in the cliff, the bottom and the underground river profiles were 67.17, 85.36 and 101.67 ng x d(-1), respectively. The 2-3 rings PAHs (including phenanthrene, anthracene, napnthalene and fluorene) accounted for 87.97% of the total of PAHs. The transport and accumulation processes of PAHs in air in Dashiwei Sinkholes were: the ground to the cliff section to the bottom section and then to the underground river, and the total PAHs concentrations showed an obvious increasing tendency with the decrease in altitude or increase in the length of the underground river. Low molecular weight PAHs compounds (including phenanthrene, anthracene, flourene and fluoranthene) in air went through differentiation at the bottom of the west peak, the bottom of the sinkhole and the underground river. The primary sources of PAHs were pyrogenic sources with atmosphere transport. Ambient temperature was the predominating factor influencing the transport and accumulation of gas phase PAHs in Dashiwei Sinkholes, following by wind speed, wind direction and relative humidity. Relative humidity and the temperature were the predominating factors influencing the differentiation, following by wind speed and wind direction. As a whole, a "cold trapping effect" of POPs was showed obviously in Dashiwei Sinkholes.

[Environmental factors on distribution of polycyclic aromatic hydrocarbons in soils from Dashiwei karst giant doline (Tiankeng) in Guangxi, China].

With typical Dashiwei karst great doline (Tiankeng) located in Leye county, Guangxi in China as study area, the soil samples of different karst topography were collected and analyzed utilizing GC-MS for the 16 PAHs. Environmental factors were observed by weather instrument. The results showed that the total PAHs concentration in soils of the ground (the positive landform) of Dashiwei great doline ranged from 75.20 ng x g(-1) to 373.79 ng x g(-1), with an average of 120.70 ng x g(-1). In Dashwei great doline (the negative landform), the total PAHs concentration in soils of cliff ranged from 19.88 ng x g(-1) to 330.79 ng x g(-1), with an average of 131.86 ng x g(-1); the concentration of the bottom section ranged from 127.48 ng x g(-1) to 661.62 ng x g(-1), with an average of 395.22 ng x g(-1); and the concentration of the underground river ranged from 1132.11 ng x g(-1) to 1 749.95 ng x g(-1), with an average of 1412.39 ng x g(-1). The PAHs compounds were mainly 4-6 rings PAH. The primary sources of PAHs were pyrogenic sources. The pollution approaches were mainly atmospheric transportation and deposition. As a whole, the spatial distribution of PAHs in soils in Dashiwei doline gradually increased from the surface-the cliff-the bottom-the underground river with the increase of temperature and relative humidity. Accumulation and differentiation of PAHs in a vertical way were showed by "coal trap effect". Environmental factors influencing the distribution of PAHs in soils were majorly temperature, followed by humidity, wind direction and wind speed, and in some parts multi environmental factors worked together. The effect of the environmental factors was bigger in summer than in winter. Monitoring of PAHs discovered that the total PAHs concentration in soils of the bottom was 3.5 times higher in 2007 than in 2006. As a consequence, this study suggested that the accumulation and differentiation of karst doline was related with these important environmental factors.

[Atmospheric deposition of PAHs in Dashiwei Karst Tiankeng Group in Leye, Guangxi].

In order to understand atmospheric deposition of polycyclic aromatic hydrocarbons impact on ecological environment of Dashiwei Karst Tiankeng Group in Leye County, Guangxi (National Geological Park), the dry and wet deposition samples around Dashiwei Tiankeng were collected by season for a year, and were analyzed utilizing GC-MS for 16 EPA PAHs. The results showed that PAH depositional fluxes ranged from 132.36-1 655.27 ng x (m2 x d)(-1), with an average value of 855.00 ng x (m2 x d)(-1). Weight of PAHs which deposited into Dashiwei Tiankeng was 51.98 g x a(-1), and the dominant PAH compounds are benzo[b] fluoranthene, chrysene, benzo[a] pryene, benzo[k]fluoranthene, anthracene, phenanthrene and naphthalene. Spatial distribution of PAHs around Dashiwei Tiankeng was: the east valley entrance > the south valley entrance > the north valley entrance > the west peak; seasonal variability of PAH depositional fluxes was: spring > summer > autumn > winter. Deposition fluxes of PAHs were 4.6 times higher in spring and summer than those in autumn and winter. The dominant PAH compounds were 4-6 rings PAHs in spring and summer, but the dominant PAH compounds were 2-3 rings PAHs in autumn and winter. PAH depositional fluxes in this study area were closely related with precipitation, wind direction, temperature, wind speed and location of pollution sources. PAHs increased in spring and summer in Dashiwei Karst Tiankeng Group, this could be transported by atmospheric movement from higher air temperature and lower elevation areas where industry developed in Guangxi.