Homeostasis Model Assessment for Insulin Resistance Mediates the Positive Association of Triglycerides with Diabetes.

Elevated circulating triglyceride levels have been linked to an increased risk of diabetes, although the precise mechanisms remain unclear. This study aimed to investigate whether low-density lipoprotein (LDL) cholesterol, homeostatic model assessment (HOMA) for insulin resistance, and C-reactive protein (CRP) served as mediators in this association across a sample of 18,435 US adults. Mediation analysis was conducted using the PROCESS Version 4.3 Macro for SPSS. Simple mediation analysis revealed that all three potential mediators played a role in mediating the association. However, in parallel mediation analysis, where all three mediators were simultaneously included, HOMA for insulin resistance remained a significant mediator (indirect effect coefficient, 0.47; 95% confidence interval [CI], 0.43-0.52; p < 0.05) after adjusting for all tested confounding factors. Conversely, LDL cholesterol (indirect effect coefficient, -0.13; 95% CI, -0.31-0.05; p > 0.05) and C-reactive protein (indirect effect coefficient, 0.01; 95% CI, -0.003-0.02; p > 0.05) ceased to be significant mediators. HOMA for insulin resistance accounted for 49% of the association between triglycerides and diabetes. In conclusion, HOMA for insulin resistance was the dominant mediator underlying the association between triglycerides and diabetes. Therefore, reducing triglyceride levels may hold promise for improving insulin sensitivity in diabetic patients.

The pollution characteristics and risk assessment of microplastics in mollusks collected from the Bohai Sea.

Microplastics (MPs) pollution in the marine environment has become a global problem. In this study, a number of 21 mollusk species (n = 2006) with different feeding habits were collected from 11 sites along the Bohai Sea for MPs uptake analysis. The MPs in mollusk samples were isolated and identified by micro-Fourier Transform Infrared Spectroscopy (µ-FTIR), and an assessment of the health risks of MPs ingested by mollusk consumption is also conducted. Approximately 91.9 % of the individuals among all the collected species inhaled MPs, and there was an average abundance of 3.30 ± 2.04 items·individual-1 or 1.04 ± 0.74 items·g-1 of wet weight. The shape of MPs was mainly fiber, and a total number of 8 polymers were detected, of which rayon had the highest detection rate (58.3 %). The highest abundance, uptake rate and polymer composition of MPs was observed in creeping types, suggesting that they might ingest these MPs from their food. The gastropod Siphonalia subdilatata contains the highest levels of MPs, which may increase the risk of human exposure if consumed whole without removing the digestive gland. The polymer risk level of MPs in these mollusks was Level III (H = 299), presenting harmful MPs such as polyvinyl chloride. In terms of human exposure risk, the average risk of human exposure to MPs through consumption of Bohai mollusks is estimated to be 3399 items·(capita·year)-1 (424-9349 items·(capita·year)-1). Overall, this study provides a basis for the ecological and health Risk assessment of MPs in mollusks collected from the coastline of China.

Assessment of the Prognostic Value of MRI Left Ventricular Global Function Index (LVGFI) in Patients With End-Stage Renal Disease Under Maintenance Dialysis.

BACKGROUND: Left ventricular global function index (LVGFI) integrates LV volumetric and functional parameters. In patients with end-stage renal disease (ESRD), cardiac injury manifests as LV hypertrophy and dysfunction. However, the prognostic value of LVGFI in this population remains unclear. PURPOSE: To investigate the association of LVGFI with major adverse cardiac events (MACE) in patients with ESRD. STUDY TYPE: Prospective. POPULATION: One hundred fifty-eight ESRD patients (mean age: 54.1 ± 14.4 years; 105 male) on maintenance dialysis. FILED STRENGTH/SEQUENCE: 3.0 T, balanced steady-state free precession (bSSFP) cine and modified Look-Locker inversion recovery (MOLLI) sequences. ASSESSMENT: LV volumetric and functional parameters were determined from bSSFP images. LVGFI was calculated as the ratio of stroke volume to global volume and native T1 was determined from MOLLI T1 maps. MACE was recorded on follow up. Models were developed to predict MACE from conventional risk factors combined with LVGFI, GLS, native T1, and LV mass index (LVMI), respectively. Subgroup analyses were further performed in participants with LVEF above median. STATISTICAL TESTS: Cox proportional hazard regression and log-rank test were used to investigate the association between LVGFI and MACE. The predictive models were evaluated and compared using Harrell's C-statistics and DeLong tests. A P value <0.05 was considered statistically significant. RESULTS: Thirty-four MACE occurred during the median follow-up period of 26 months. The hazard of MACE increased by 114% for each 10% decrease in LVGFI in univariable analysis. The predictive model consisting of LVGFI (C-statistic: 0.724) had significantly better predictive performance than the others (all P < 0.001). These results were consistent in patients (N = 79) with LVEF > median (63.54%). DATA CONCLUSION: LVGFI is a novel marker for MACE risk stratification in patients with ESRD and was better able to predict MACE than native T1 mapping and GLS. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.

Costs and health benefits of the rural energy transition to carbon neutrality in China.

The rural energy transition is critical in China's efforts to achieve carbon neutrality and improve air quality. However, the costs and health benefits associated with the transition to carbon neutrality remain unclear. Here we explore the cost-effective transition pathways and air quality-related health impacts using an integrated energy-air quality-health modeling framework. We find that decarbonizing rural cooking and heating would triple contemporary energy consumption from 2014 to 2060, considerably reducing energy poverty nationwide. By 2060, electric cooking ranges and air-to-air heat pumps should be widely integrated, costing an additional 13 billion USD nationally in transformation costs, with ~40% concentrated in Shandong, Heilongjiang, Shanxi and Hebei provinces. Rural residential decarbonization would remarkably improve air quality in northern China, yielding substantial health co-benefits. Notably, monetized health benefits in most provinces are projected to offset transformation costs, except for certain relatively lower-development southwestern provinces, implying more financial support for rural residents in these areas will be needed.

Assessment of green roofs' potential to improve the urban thermal environment: The case of Beijing.

Against the backdrop of global warming, rapid urbanization has caused the aggregation of urban building spaces and the heat island effect is becoming increasingly serious, hindering sustainable urban development. In order to investigate the potential and methods of green roofs in different types of neighborhoods to mitigate the urban heat island effect, this study used multivariate data for surface temperature inversion and local climate zone (LCZ), and the potential of green roofs to reduce the heat island effect was evaluated by combining LCZ zoning and ENVI-met prediction model. Finally, a multi-scenario analysis with economic factors was conducted to derive the optimal implementation path for green roofs. The results show that in LCZs 1-9, the green roof can reduce the daytime average air temperature by a maximum of 0.41 °C for 0.5 m of the LCZ8 roof and 0.37 °C for 1.2 m of the LCZ6 pedestrian. Based on the surface cooling efficiency of LCZ green roofs get the best green roof construction order: LCZ3, LCZ6, LCZ8 > LCZ2, LCZ5, LCZ7 > LCZ1, LCZ4, LCZ9. The construction of green roofs for the heat island areas within the fifth ring road of Beijing can reduce the area of high-temperature and sub-high-temperature zones by 52.55% and 29.17%, respectively, compared with the area without green roof construction. The study clarifies the technical methodology system of cooling efficiency of green roofs in different types of neighborhoods and the reduction of the urban-scale heat island effect, which provides a reference for the planning of green roofs for urban buildings.

Multiparametric ultrasound for the assessment of testicular lesions with negative tumoral markers.

The purpose of this study was to evaluate the diagnostic performance of multiparametric ultrasound (mpUS; grayscale US, color Doppler US, strain elastography, and contrast-enhanced US) in the assessment of testicular lesions with negative tumoral markers. MpUS imaging data, patient age, serum tumor markers, scrotal pain, cryptorchidism, and related clinical information were retrospectively collected for patients who underwent mpUS examination between January 2013 and December 2019. Histologic results or follow-up examinations were used as the reference standard. In total, 83 lesions from 79 patients were included in the analysis. Fifty-six patients were finally diagnosed with benign tumors, and 23 patients were ultimately diagnosed with malignant tumors. Chi-square tests or Fisher's exact tests were used to assess the difference between the two groups. Stepwise multivariate logistic regression analysis showed that lesion diameter (odds ratio [OR] = 1.072, P = 0.005), vascularization on color Doppler US (OR = 4.066, P = 0.001), and hyperenhancement during the early phase (OR = 6.465, P = 0.047) were significant independent risk factors for malignancy; however, when compared with neoplastic lesions, pain (OR = 0.136, P < 0.001), absence of vascularization on color Doppler US (OR = 1.680, P = 0.042), and nonenhancement during the late phase (OR = 3.461, P = 0.031) were strongly associated with nonneoplastic lesions. MpUS features are useful for differentiating testicular lesions with negative tumoral markers and improving the preoperative diagnosis, which may avoid inappropriate radical orchiectomy.

Contrast-enhanced ultrasound in the assessment of Crohn's disease activity: comparison with computed tomography enterography.

BACKGROUND AND OBJECTIVE: Continuous assessment of disease activity remains a huge challenge during the follow-ups of patients with Crohn's disease (CD). In this paper, we aimed to evaluate the performance of contrast-enhanced ultrasound (CEUS) by comparing with computed tomography enterography (CTE) in the assessment of disease activity in CD. MATERIALS AND METHODS: Fifty-two patients diagnosed with CD were included in this study, using the CEUS and CTE as imaging methods for comparison. The selected parameters included the location and thickness of the thickest part of the intestinal wall, mesenteric fat proliferation, mesenteric vessels change, enhancement pattern and the presence of complications. Patients were clinically assessed using the Crohn's disease activity index (CDAI), C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). Simple endoscopic score for Crohn's disease (SES-CD) was regarded as the reference standard. RESULTS: The location of the thickest part of the intestinal wall (κ = 0.653), bowel wall thickness (ICC = 0.795), mesenteric vessels change (κ = 0.692) and complications (κ = 0.796) displayed substantial agreement (0.61-0.80) between CEUS and CTE, while the detection of mesenteric fat proliferation (κ = 0.395) and enhancement pattern (κ = 0.288) showed fair consistency (0.21-0.40) for comparison. In CEUS, bowel wall thickness, mesenteric fat proliferation, enhancement pattern and mesenteric vessels change were statistically significant in assessing CD activity, while bowel wall thickness, mesenteric fat proliferation and mesenteric vessels change in CTE. Bowel wall thickness showed the best diagnostic performance in the assessment of CD activity at CEUS and CTE. CONCLUSION: CEUS provides a radiation-free and effective way to assess the CD activity in comparison with CTE, which also avoids frequent colonoscopy examinations, improves tolerance of patients, and reduces the cost of medical care, thereby serving as a useful tool for CD follow-up.

Implications of wheat straw logistic systems for bioenergy sustainable development in China: Costs, energy consumption, and GHG emissions.

Wheat straw is a priority choice for bioenergy production, bioenergy as the essential low carbon emissions energy can be a good choice for alternating the petroleum-based fuels. In this study, face-to-face surveys were conducted to analyze the costs, energy consumption, and greenhouse gas emissions involved in wheat straw logistic systems in China. The result identified five logistic modes, including two short-distance transportation and three long-distance transportation modes. These five modes exhibited costs ranging from 17.34-31.95 $ t-1, energy consumption between 108.30 and 1060.45 MJ t-1, and greenhouse gas emissions ranging from 0.71-11.52 kg CO2-eq t-1. A sensitivity analysis showed that the most important parameters in the short-distance transport group were the harvest rate and the bale weight. In the long-distance transport group, the distance from the depot to the end user and the truck capacity. After an overall consideration of the costs, energy consumption, and greenhouse gas emissions, an optimal wheat straw logistic system was found in the short-distance transport group due to maximum harvest rate and bale weight by using better combines and balers. Whereas the distance from the depot to the end user should be reduced and higher capacity trucks should be used to have relatively optimal modes for the long-distance transport group. This study provides a valuable reference for bioenergy industries in feedstock collection.

Validation of an 8-item Recovery Assessment Scale (RAS-8) for people with schizophrenia in China.

BACKGROUND: The 24-item Recovery Assessment Scale (RAS) is the most widely-used and well-validated tool for measuring recovery for people with mental illness. The current study aims to assess the reliability and validity of an 8-item short form of RAS (RAS-8) among a Chinese sample of people living with schizophrenia. METHODS: A sample of 400 people living with schizophrenia were recruited for scale validation. Internal consistency was tested by calculating Cronbach's α. Test-retest reliability was calculated using the intraclass correlation coefficient (ICC) for the total score and weighted kappa for each item. Factor structure was tested with confirmatory factor analysis, and concurrent validity was examined by investigating the correlation of the RAS-8 with patient symptoms, disability, depression, anxiety, patient functioning, quality of life and general health. RESULTS: The RAS-8 full scale and subscales showed good internal consistency with Cronbach's alpha ranging from 0.87 to 0.92. ICC of 0.99 and weighted kappa ranged from 0.62 to 0.88, which generally indicates good test-retest reliability. The findings supported an a priori two-factor structure, χ2/df = 2.93, CFI = 0.98, TLI = 0.98, RMSEA = 0.07, SRMR = 0.035. Concurrent validity of the RAS-8 was further supported by its significant negative correlations with patient symptoms (r = -0.24, p < 0.01), disability (r = -0.30, p < 0.01), depression (r = -0.16, p < 0.05), and anxiety (r = -0.14, p < 0.05), and its significant positive relationships with patient functioning (r = 0.26, p < 0.01), quality of life (r = 0.39, p < 0.01) and general health (r = 0.34, p < 0.01). CONCLUSIONS: This study confirmed the reliability and validity of an 8-item short-form RAS for people living with schizophrenia in Chinese communities. The validation of the RAS-8 allows for its use as an alternative for the full RAS as a rapid assessment tool in clinical and research settings. The findings are discussed for their implications for application and validation with other populations and in other countries.

Usefulness of Strain Elastography, ARFI Imaging, and Point Shear Wave Elastography for the Assessment of Crohn Disease Strictures.

OBJECTIVES: The aim of this study was to evaluate the diagnostic performance of strain elastography, acoustic radiation force impulse (ARFI) imaging and point shear wave elastography (p-SWE) for assessment of the predominant types of intestinal stenosis in Crohn disease. METHODS: Twenty-five patients were enrolled in this study, among whom 25 suspicious stenoses in 25 intestinal segments were studied using gray scale ultrasonography. All 3 elastography methods were performed, and all patients underwent endoscopy within 24 hours with pathologic biopsy. The sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), Youden index, and area under the receiver operating characteristic curve (AUROC) were calculated. Pathologic findings were regarded as the gold standard. RESULTS: For SE, the optimal cutoff value was a score of 4 or greater (sensitivity, 75%; specificity, 66.7%; accuracy, 68%; PPV, 30%; NPV, 93.3%; AUROC, 0.708; however, P > .05). The results of ARFI imaging were similar: the optimal cutoff value was a score of 4 or greater (sensitivity, 50%; specificity, 81%; accuracy, 76%; PPV, 33.3%; NPV, 89.4%; AUROC, 0.669; P < .05). However, for p-SWE, the optimal cutoff value was reached when the shear wave velocity exceeded 2.73 m/s (sensitivity, 75%; specificity, 100%; accuracy, 96%; PPV, 100%; NPV, 95.5%; AUROC, 0.833; P < .05). CONCLUSIONS: p-SWE had the best performance for evaluating and differentiating intestinal stenosis in Crohn disease, while neither SE nor ARFI imaging achieved satisfactory outcomes for evaluating inflammatory stenosis and fibrotic stenosis of Crohn disease.

Ecological and economic benefits of planting winter rapeseed (Brassica rapa L.) in the wind erosion area of northern China.

Winter and early spring wind soil erosion have considerable impacts on ecosystems, human well-being and agricultural production in the low precipitation zones of northern China. Little is known about the impact of growing winter rapeseed on ecological cropping systems and the associated economic benefits in the wind erosion area. To explore the winter rapeseed cover effect, we conducted a field experiment in which we covered the soil with winter rapeseed, winter wheat and wheat stubble at different plant density levels and used the spring bare ground as the control (CK). The effects of wind erosion, the "winter rapeseed + " multiple cropping system, and the economic benefits were compared. There was a large difference in the dry matter, the maximum water absorption, the maximum water storage, the soil evaporation and total wind erosion, the amount of sediment transported in the stratum and the wind erosion modulus. Among them, the mean wind erosion modulus of spring sowing bare land was as high as 490.9 kg·hm-2·h-1, which was 7 and 13 times that of winter wheat and winter rapeseed, respectively. As the wind speed increased from 14 to 22 m·s-1, from a small density to a large density, the mean wind erosion modulus decreased from 68 to 17 kg·hm-2·h-1 for winter rapeseed, and 150 to 31 kg·hm-2·h-1 for winter wheat. Total wind-erosion of sediment transport of CK was 18.6 g·m-2 min-1, which was 16 and 31 times the mean value of winter wheat and winter rapeseed, respectively. "Winter rapeseed + " replanting peanuts, potatoes, rice, seed melons and other crops generally increased the production value by 5-74% compared with wheat and corn intercropping, which was 98-255% higher than the traditional wheat single crop. Our results suggested that the suitable area for planting winter rapeseed in northern China was approximately 3.3 × 106 hm2, and in terms of the best economic and ecological effects, the appropriate density was 5 × 105 plants·hm-2 in northern China. Our results indicated that Chinese winter rapeseed was the best choice for preventing wind erosion and improving ecological and economic benefits in winter and spring in northern China; additionally, winter rapeseed has important impacts on agricultural sustainability in semi-arid and arid climates.

Mismatch in Children's Weight Assessment, Ideal Body Image, and Rapidly Increased Obesity Prevalence in China: A 10-Year, Nationwide, Longitudinal Study.

OBJECTIVE: This study examined secular trends in children's weight-status assessment, measured weight status, and ideal body image and their associations with subsequent changes in BMI, and it explored the differences between sociodemographic groups in China. METHODS: Longitudinal data from the China Health and Nutrition Survey of 4,605 children aged 6 to 17 collected between 2000 and 2011 were used and fitted to mixed models. RESULTS: From 2000 to 2011, overweight/obesity prevalence increased from 6.5% to 16.8%, but the percentage of children with self-perceived weight status as "fat" remained around 2.0%; 49.0% of children underestimated their weight status at baseline. Self-perceived body image of most participants was tracked during follow-up. Children who perceived themselves as being fat at baseline had a higher BMI increase over time during follow-up than those with an average body image (ß [SE] = 0.99 [0.14] kg/m2 per year, P < 0.001). Boys, young children, recent cohorts, and rural children had higher BMI increases than their counterparts. Over time, the thin-body silhouette became more desirable (8.4 percentage points higher, P < 0.001). CONCLUSIONS: Chinese children experience a large incongruence between their weight-status assessment, ideal body image, and actual weight status. Health promotion programs should examine their role in assisting children in developing a healthy body image and gaining greater self-motivation toward promoting a healthy lifestyle.

Exploring Market State and Stock Interactions on the Minute Timescale.

A stock market is a non-stationary complex system. The stock interactions are important for understanding the state of the market. However, our knowledge on the stock interactions on the minute timescale is limited. Here we apply the random matrix theory and methods in complex networks to study the stock interactions and sector interactions. Further, we construct a new kind of cross-correlation matrix to investigate the correlation between the stock interactions at different minutes within one trading day. Based on 50 million minute-to-minute price data in the Shanghai stock market, we discover that the market states in the morning and afternoon are significantly different. The differences mainly exist in three aspects, i.e. the co-movement of stock prices, interactions of sectors and correlation between the stock interactions at different minutes. In the afternoon, the component stocks of sectors are more robust and the structure of sectors is firmer. Therefore, the market state in the afternoon is more stable. Furthermore, we reveal that the information of the sector interactions can indicate the financial crisis in the market, and the indicator based on the empirical data in the afternoon is more effective.

Intrinsic Multi-Scale Dynamic Behaviors of Complex Financial Systems.

The empirical mode decomposition is applied to analyze the intrinsic multi-scale dynamic behaviors of complex financial systems. In this approach, the time series of the price returns of each stock is decomposed into a small number of intrinsic mode functions, which represent the price motion from high frequency to low frequency. These intrinsic mode functions are then grouped into three modes, i.e., the fast mode, medium mode and slow mode. The probability distribution of returns and auto-correlation of volatilities for the fast and medium modes exhibit similar behaviors as those of the full time series, i.e., these characteristics are rather robust in multi time scale. However, the cross-correlation between individual stocks and the return-volatility correlation are time scale dependent. The structure of business sectors is mainly governed by the fast mode when returns are sampled at a couple of days, while by the medium mode when returns are sampled at dozens of days. More importantly, the leverage and anti-leverage effects are dominated by the medium mode.

Global establishment risk of economically important fruit fly species (Tephritidae).

The global invasion of Tephritidae (fruit flies) attracts a great deal of attention in the field of plant quarantine and invasion biology because of their economic importance. Predicting which one in hundreds of potential invasive fruit fly species is most likely to establish in a region presents a significant challenge, but can be facilitated using a self organising map (SOM), which is able to analyse species associations to rank large numbers of species simultaneously with an index of establishment. A global presence/absence dataset including 180 economically significant fruit fly species in 118 countries was analysed using a SOM. We compare and contrast ranked lists from six countries selected from each continent, and also show that those countries geographically close were clustered together by the SOM analysis because they have similar fruit fly assemblages. These closely clustered countries therefore represent greater threats to each other as sources of invasive fruit fly species. Finally, we indicate how this SOM method could be utilized as an initial screen to support prioritizing fruit fly species for further research into their potential to invade a region.

[Safe wintering and economic and ecological benefit of winter rapeseed in dry and cold areas of northern China].

The purpose of this study was to realize the security of safe wintering of winter rapeseed in dry and cold regions of northern China. Experiments were conducted with 18 winter rapeseed (Brassica campestris) varieties at 57 sites from 2008 to 2013 to statistically analyze the wintering rate variation of different varieties in dry and cold regions of northern China. The results showed that, the wintering rate varied from 70% to 90% during the study period in different regions, which had no significant difference between different years and varieties, and had high stability and remarkable economic benefit. With Tianshui as a starting point of winter rapeseed planting, the wintering-safe regions included all Gansu Province , the south of Lasa and Linzhi of Xizang, the east of Minhe of Qinghai, up to Urumqi and Baicheng, and the south of Aletai, Tacheng, the east of Kashi of Xinjiang, it also included the regions along Yellow River eastward to Ningxia, the south of Linhe of Inner Mongolia, the north of Shaanxi, the vicinage of Qixian in Shanxi, Daming in Hebei, Tianjin, Beijing, the north of Weifang of Shandong, the south of Huludao of Liaoning and Yanbian of Jilin. Longyou 6, Longyou 7, Longyou 8 and Longyou 9 were the wintering-safe B. rapa varieties.

[Assessment of heavy metal contamination by moss-bag method and road-dust method for Taizhou urban area].

The aims of this study were to examine the contents and distribution character of heavy metals in urban areas of Taizhou, Jiangsu Province. Contents of 8 kinds of metals, including As, Cd, Cr, Cu, Mn, Ph, V and Zn, in the moss-bags and road dusts were determined, and the method of potential ecological risk index was used to assess the heavy metal contamination. The results indicated that the current situation of heavy metal contamination was serious in Taizhou, and the ecological risks of heavy metals were high. The mean concentrations of Cd, Zn, Pb in the air near the ground were 8.41 , 6.94 and 5. 85 times higher than the soil background values, respectively; and the mean concentrations of Zn, Cd, Pb, and Cu in the road dusts were 22. 63, 6. 58, 5. 13 and 4. 45 times higher than the soil background values, respectively. The results of potential ecological risk index showed that Cd was the main ecological risk factor both in the air near the ground and the road soils, its contribution rates in ecological risks accounted for 92.43% in the air near the ground and 72. 46% in the road soils. The Pearson correlation coefficients of heavy metals showed that there was a significant correlation among the heavy metals in the air near the ground, which implied the sources of pollution in the air were fewer than those of the road dust. Analysis indicated that traffic emission was the major anthropogenic source and the key influencing factor for heavy metal contamination of Taizhou, and that the potential ecological risk of bus stations were the highest.

[Analysis and assessment of atmospheric pollution based on accumulation characterization of heavy metals in Platanus acerifolia leaves].

The present work was aimed to evaluate the heavy metal pollution in the atmosphere of Huainan City. We measured and clustered the accumulation of six heavy metals in Platanus acerifolia leaves in 20 sampling fields with six types of environmental conditions, and analyzed the EF value of heavy metal enrichment in the leaves. The results showed that the accumulations in Platanus acerifolia leaves varied according to different types of metals, following the order of Zn > Cu > Cr > Ni > Pb > Cd. Environmental conditions also had great influence on the accumulation of heavy metals. Cd and Cu were mostly found in cement plant and mine, respectively, and Cr, Ni, Pb and Zn were significant higher in main road, compared with other environmental conditions. The average values of EF for all the metals expect Cr in scenic and village area were over 1. The average values of EF for all the metals in mine, power plant, main road and cement plant were above 3. The overall pollution condition of heavy metals in Huainan City followed the order of Cd > Cu > Zn > Ni > Pb > Cr.

Chitin synthase A: a novel epidermal development regulation gene in the larvae of Bombyx mori.

Chitin synthase is the key regulatory enzyme for chitin synthesis and excretion in insects, as well as a specific target of insecticides. The chitin synthase A gene (BmChsA) cloned from Bombyx mori, the model species of lepidopteran, is an epidermis-specific expressed gene during the molting stage. Knockdown BmChsA gene in 3rd instar larvae increased the number of non-molting and abnormal molting larvae. Exposure to nikkomycin Z, a chitin synthase inhibitor downregulated the expression of BmChsA and decreased the amount of epidermis chitin during the molting process. The thickness of the new epidermis and its dense structure varied greatly. The exogenous hormones significantly upregulated the expression of BmChsA with low levels of endogenous MH and high levels of endogenous JH immediately after molting. With low levels of endogenous hormones during the mulberry intake process, BmChsA was rarely upregulated by exogenous hormones. With high levels of endogenous MH and low levels of endogenous JH during the molting stage, we did not detect the upregulation of BmChsA by exogenous hormones. The expression of BmChsA was regulated by endocrine hormones, which directly affected the chitin synthesis-dependent epidermal regeneration and molting process.

Allele-specific polymerase chain reaction for detection of a mutation in the relax circular DNA and the covalently closed circular DNA of hepatitis B virus.

The relax circle DNA (rcDNA) sequence and the covalently closed circle DNA (cccDNA) sequence in hepatitis B virus (HBV) are crucial regions for HBV infections. To analyze mutations in rcDNA and cccDNA, DNA sequencing is often used, although it is time-consuming and expensive. Herein, we report a simple, economic, albeit accurate allele-specific polymerase chain reaction (AS-PCR) to detect mutations in these regions of HBV. This method can be extensively used to screen for mutations at specific positions of HBV genome.