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Paraquat (PQ) is one of the most commonly used herbicides, but it has polluted the environment and threatened human health through extensive and improper usage. Here, a new naked-eye PQ immunochromatographic strip was developed to recognize PQ in domestic water and real human samples within 10 min based on a novel custom-designed anti-PQ antibody. The PQ test strip could recognize PQ at a concentration as low as 10 ng/ml, reaching the high-efficiency time-of-flight mass spectrometry detection level and identifying trace amounts of PQ in samples treated with a diquat (DQ) and PQ mixture. Notably, both the performance evaluation and clinical trial of the proposed PQ strips were validated in multiple hospitals and public health agencies. Taken together, our study firstly provide the clinical PQ-targeted colloidal gold immunochromatographic test strip designed both for environment water and human sample detection with multiple advantages, which are ready for environmental monitoring and clinical practice.

During coronavirus (SARS-CoV2) the number of fraudulent transactions is expanding at a rate of alarming (7352421 online transaction records). Additionally, the Master Card (MC) usage is increasing. To avoid massive losses, companies of finance must constantly improve their management information systems for discovering fraud in MC. In this paper, an approach of advancement management information system for discovering of MC fraud was developed using sequential modeling of data depend on intelligent forecasting methods such as deep Learning and intelligent supervised machine learning (ISML). The Long Short-Term Memory Network (LSTM), Logistic Regression (LR), and Random Forest (RF) were used. The dataset is separated into two parts: the training and testing data, with a ratio of 8:2. Also, the advancement of management information system has been evaluated using 10-fold cross validation depend on recall, f1-score, precision, Mean Absolute Error (MAE), Receiver Operating Curve (ROC), and Root Mean Square Error (RMSE). Finally various techniques of resampling used to forecast if a transaction of MC is genuine/fraudulent. Performance for without re-sampling, with under-sampling, and with over-sampling is measured for each Algorithm. Highest performance of without re-sampling was 0.829 for RF algorithm-F score. While for under-sampling, it was 0.871 for LSTM algorithm-RMSE. Further, for over-sampling, it was 0.921 for both RF algorithm-Precision and LSTM algorithm-F score. The results from running advancement of management information system revealed that using resampling technique with deep learning LSTM generated the best results than intelligent supervised machine learning.

Molecular generation is an important but challenging task in drug design, as it requires optimization of chemical compound structures as well as many complex properties. Most of the existing methods use deep learning models to generate molecular representations. However, these methods are faced with the problems of generation validity and semantic information of labels. Considering these challenges, we propose a cross-adversarial learning method for molecular generation, CRAG for short, which integrates both the facticity of VAE-based methods and the diversity of GAN-based methods to further exploit the complex properties of Molecules. To be specific, an adversarially regularized encoder-decoder is used to transform molecules from simplified molecular input linear entry specification (SMILES) into discrete variables. Then, the discrete variables are trained to predict property and generate adversarial samples through projected gradient descent with corresponding labels. Our CRAG is trained using an adversarial pattern. Extensive experiments on two widely used benchmarks have demonstrated the effectiveness of our proposed method on a wide spectrum of metrics. We also utilize a novel metric named Novel/Sample to measure the overall generation effectiveness of models. Therefore, CRAG is promising for AI-based molecular design in various chemical applications.

Security has become one of the important factors for any network communication and transmission of data packets. An organization with an optimal security system can lead to a successful business and can earn huge profit on the business they are doing. Different network devices are linked to route, compute, monitor, and communicate various real-time developments. The hackers are trying to attack the network and want to draw the organization’s significant information for its own profits. During the communication, if an intrusion or eavesdropping occurs, it will lead to a severe disfigurement of the whole communication network, and the data will be controlled by wrong malicious users. Identification of attack is a way to identify the security violations and analyze the measures in a computer network. An identification system, which is effective and accurate, can add security to the existing system for secure and smooth communication among end to end nodes and can work efficiently in the identification of attack on data packets. The role of information security is to design and protect the entire data of networks and maintain its confidentiality, integrity, and availability for their right users. Therefore, there is a need for end to end security management, which will ensure the security and privacy of the network and will save the data inside networks from malicious users. As the network devices are growing, so the level of threats is also increasing for these devices. The proposed research is an endeavor toward the detection of data packets attack by using the rough set theory for a secure end to end communication. The experimental work was performed by the RSES tool. The accuracy of the K-NN was 88% for the total objects of 8459. For cross validation purposes, the decision rules and decomposition tree algorithms were used. The DR algorithm showed accuracy of 59.1%, while the DT showed accuracy of 61.5%. The experimental results of the proposed study show that the research is capable of detecting data packets attack.

Position feedback and closed loop control are very important for MEMS mirror owing to the fact that the amplitude-frequency response of MEMS mirror is very susceptible to ambient temperature. This work reports a capacitive feedback solution of electrostatic driven MEMS mirror. To avoid the feedthrough of high voltage driving signal, a pulse width modulation (PWM) driving signal with low duty cycle and a current to voltage converter sensing circuit are employed. To eliminate the crosstalk induced by feedthrough, the sensing circuit is switched on only when the PWM signal is periodically low or grounded, but switched off during the PWM rise, fall and on-state time. The relationship between the electric sensing signal and the rotation angle is mathematically modeled, analyzed and experimentally verified. As a result of this research, sensing signal detection during the low state time of PWM is proved to be feasible to eliminate the influence of the actuation feedthrough. The peak value and the time when the sensing signal turns from negative to positive can be used to measure the amplitude and phase of the MEMS mirror with a precision of 3.10 and 0.13 mrad, respectively.

Exposure to low-dose benzene may lead to hematotoxicity and cause health problems. Though peripheral blood cell count is widely used in benzene exposure assessment and health risk assessment, the reports regarding the effects of low-dose benzene exposure on blood cell count remain inconsistent. To uncover more sensitive biomarkers for low-dose benzene exposure, our previous study screened out three potential serum proteins-plasminogen (PLG), platelet basic protein (PBP) and apolipoprotein B100 (ApoB100)-as biomarkers from chronic benzene poisoning patients by using proteomic analysis. In the present study, we verify the three serum proteins as biomarkers for the effects of low-dose benzene exposure in a large low-dose benzene exposure population. The study showed that serum PLG increased in benzene exposed workers and was positively correlated with benzene exposure levels. However, no significant changes in serum PBP or ApoB100 were found in the benzene exposed workers. To explore whether the candidate serum proteins are associated with hematotoxicity, the study population was regrouped into two groups, based on their WBC counts. Our results showed that the workers with high serum PLG levels suffered higher risk of WBC abnormalities than did workers with low serum PLG levels. Taken together, these findings indicate that the increase in serum PLG might be associated with low-dose benzene exposure and benzene-induced hematotoxicity. Thus, we suggest serum PLG could be used as a potential biomarker for the effects of low-dose benzene exposure.

Calcium carbonate nanomaterials (nano-CaCO3) are widely used in both manufacturing and consumer products, but their potential health hazards remain unclear. The objective of this study was to survey workplace exposure levels and health effects of workers exposed to nano-CaCO3. Personal and area sampling, as well as real-time and dust monitoring, were performed to characterize mass exposure, particle size distribution, and particle number exposure. A total of 56 workers (28 exposed workers and 28 unexposed controls) were studied in a cross-sectional study. They completed physical examinations, spirometry, and digital radiography. The results showed that the gravimetric nano-CaCO3 concentration was 5.264 ± 6.987 mg/m3 (0.037–22.192 mg/m3) at the workplace, and 3.577 ± 2.065 mg/m3 (2.042–8.161 mg/m3) in the breathing zone of the exposed workers. The particle number concentrations ranged from 8193 to 39 621 particles/cm3 with a size range of 30–150 nm. The process of packing had the highest gravimetric and particle number concentrations. The particle number concentration positively correlated with gravimetric concentrations of nano-CaCO3. The levels of hemoglobin, creatine phosphokinase (CK), lactate dehydrogenase, and high-density lipoprotein cholesterol (HDL-C) in the nano-CaCO3 exposure group increased significantly, but the white blood cell count (WBC), Complement 3 (C3), total protein (TP), uric acid, and creatinine (CREA) all decreased significantly. The prevalence rate of pulmonary hypofunction was significantly higher (p = 0.037), and the levels of vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC, peak expiratory flow and forced expiratory flow 25% (FEF 25%), FEF 25–75% were negatively correlated with gravimetric concentrations of nano-CaCO3 (p 3 exposure level was associated with pulmonary hypofunction (p = 0.005). Meanwhile, a dose-effect relationship was found between the accumulated gravimetric concentrations of nano-CaCO3 and the prevalence rate of pulmonary hypofunction (p = 0.048). In conclusion, long-term and high-level nano-CaCO3 exposure can induce pulmonary hypofunction in workers. Thus, lung function examination is suggested for occupational populations with nano-CaCO3 exposure. Furthermore, future health protection efforts should focus on senior workers with accumulation effects of nano-CaCO3 exposure.

We recently reported that occupational exposure to trimethyltin (TMT) is a risk factor for developing kidney stones. To further examine the association between TMT exposure and the formation of kidney stones, we conducted a 180-day animal study and exposed the randomly grouped Sprague-Dawley (SD) rats to TMT in the drinking water at doses of 0, 8.2, 32.8 and 131.3 µg kg(-1) day(-1). Transient behavioral changes were observed in the high-dose group during the first 2 weeks of exposure. TMT exposure led to a significant dose-dependent inhibition of renal H(+)/K(+)-ATPase and an increase in urinary pH. In comparison to no kidney stones being identified in the control and the lowest dose group, 1 rat in the 32.8 µg kg(-1) day(-1) dose group and 3 out of 9 rats in the 131.3 µg kg(-1) day(-1) dose group were found to have stones in the kidney/urinary tract. Pathological analysis showed that more wide spread calcium disposition was observed in kidneys of rats with TMT exposure compared with the rats in the control group. However, X-ray diffraction (XRD) analysis found that the kidney stones were mainly composed of struvite with the formula: NH4MgPO4 6H2O, while calcium-containing components were also detected. Together, this study further demonstrates through animal studies that chronic exposure to a relatively low level of TMT induces nephrotoxicity and increases the risk for developing kidney stones.

Nephrolithiasis (kidney stones) is a common disease with the prevalence that is increasing globally. We previously found that trimethyltin (TMT), a by-product of plastic stabilisers, can inhibit the H(+)/K(+) ATPase activity in renal intercalated cells and alter urinary pH, which is a known risk factor for nephrolithiasis. In this study, we conducted a cross-sectional analysis to evaluate the impact of chronic low level occupational TMT exposure on nephrolithiasis.This study included 216 healthy workers with TMT exposure and 119 workers as controls with no TMT exposure. All study participants were administered a questionnaire and underwent a routine clinical examination including an ultrasonographic screening for kidney stones. Exposures were assessed by measuring TMT concentrations in personal air samples, blood and urine. Logistic regression analysis was used to estimate the ORs and 95% CIs for the risk of kidney stones.TMT exposed workers had a higher prevalence of kidney stones (18.06%) in comparison with control workers (5.88%). High TMT concentrations in personal air samples, blood and urines were positively associated with increased prevalence of kidney stones in workers exposed to TMT compared with controls workers (p-trend values=0.005, 0.008 and 0.002, respectively). The length of employment in plants with elevated TMT levels (duration of the exposure) was significantly associated with the increased prevalence of kidney stones (p trend=0.001). The ORs were 2.66 for3 years, 3.73 for 3-10 years and 7.89 for 10+ years of employment compared with control workers.To our knowledge, this is the first report to demonstrate that occupational exposure to TMT is a potential risk factor for nephrolithiasis.

Extensive uses of methyltin compounds in polyvinyl chloride (PVC) production have led to a dramatic increase of occupational-related methyltin poisoning accidents and the widespread contamination of methyltins in various environmental media. Here, we conducted studies to compare the acute toxicity induced by trimethyltin (TMT) and dimethyltin (DMT), and investigated the cumulative toxic effects of TMT in rats and mice. Neurobehavioral changes were observed in rats and mice treated with either DMT or TMT, but we also observed that both TMT and DMT exposure in rats significantly lowered the blood potassium level. Moreover, the cumulative toxic coefficient factor of TMT was 1.7 in rats versus 3.8 in mice, suggesting a high cumulative risk for rats and a moderate risk for mice. In summary, we demonstrated that acute and chronic exposure to methyltin compounds induced neurotoxicity and hypokalemia. Moreover, our study suggests that TMT can accumulate in the body and pose a risk for workers chronically exposed to a low dose of TMT.

To describe the distribution of zinc (Zn) and copper (Cu) in urine samples of generalpopulation in eight provinces of China, to analyze their characteristics of distribution between different region, gender and age-cohorts, and to provide the baseline of themetabolites in the general population.From 2009 to 2010, 18 120 subjects from the general population aged from 6 to 60 years old were recruited from 24 areas among 8 provinces of China mainland by random sampling. The environmental and physical condition characteristics were collected from questionnaires, and urine samples were collected at the mean time. The levels of Zn and Cu in urine were measured using ICP-MS. Data were analyzed by statistical methods to compare the distribution characteristics of Zn and Cu among populations with different ages and genders.Totally, the median of Cu and Zn in urine were 9.28 and 115.47 µg/L respectively; and the inter-quartile range of Cu and Zn were 2.66-16.09 and 35.32-265.15 µg/L respectively. The median of Cu in male and female were 9.90 and 8.60 µg/L (Z=-5.63, P0.001), and Zn in male and female were 140.44 and 95.27 µg/L (Z=-14.79, P0.001). The median of Cu among the groups aged 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were 9.30, 10.14, 9.67, 9.33, 8.38 and 8.74 µg/L (χ2=70.94, P0.001), respectively, and the median of Zn 130.83, 132.07, 139.34, 109.3, 78.74 and 109.51 µg/L ((χ2=146.00, P0.001), respectively.There was statistically significant differences in urinary Cu and Zn levels between male and female, and among the different age groups.The Cu and Zn levels and distribution in urine among general population between 2009 and 2010 in China were reported in this article. These basic data in China will provide scientific and reliable reference for further scientific research.

Benzene is an important industrial chemical and an environmental contaminant, but the pathogenesis of hematotoxicity induced by chronic occupational benzene exposure (HCOBE) remains to be elucidated. To gain an insight into the molecular mechanisms and developmental biomarkers for HCOBE, isobaric tags for relative and absolute quantitation (iTRAQ) combined with two-dimensional liquid chromatography-tandem mass spectrometry (2D-LC-MS/MS) were utilized. Identification and quantitation of differentially expressed proteins between HCOBE cases and healthy control were thus made. Expressions of selected proteins were confirmed by western blot and further validated by ELISA. A total of 159 unique proteins were identified (≥95% confidence), and relative expression data were obtained for 141 of these in 3 iTRAQ experiments, with fifty proteins found to be in common among 3 iTRAQ experiments. Plasminogen (PLG) was found to be significantly up-regulated, whereas platelet basic protein (PBP) and apolipoprotein B100 (APOB100) were significantly down-regulated in the serum of HCOBE cases. Additionally, the altered proteins were associated with the molecular functions of binding, catalytic activity, enzyme regulator activity and transporter activity, and involved in biological processes of apoptosis, developmental and immune system process, as well as response to stimulus. Furthermore, differential expressions of PLG, PBP and APOB100 were confirmed by western blot, and the clinical relevance of PBP and APOB100 with HCOBE was validated by ELISA. Overall, our results showed that lowered expression of PBP and APOB100 proteins served as potential biomarkers of HCOBE, and may play roles in the benzene-induced immunosuppressive effects and disorders in lipid metabolism.

Trimethyltin chloride (TMT), a byproduct of plastic stabilizers, has caused 67 poisoning accidents in the world; more than 98% (1814/1849) of the affected patients since 1998 have been in China. As a long-established toxic chemical, TMT severely affects the limbic system and the cerebellum; however, its relationship with hypokalemia, a condition observed in the majority of the cases in the last decade, remains elusive. To understand the mechanism underlying hypokalemia induced by TMT, Sprague-Dawley (SD) rats were administered TMT to determine the relationship between H(+)/K(+)-ATPase activity and the blood and urine K(+) concentration and pH, respectively. H(+)/K(+)-ATPase protein and mRNA were observed too. In vitro changes to intracellular pH, K(+) channels in renal cells were measured. The results showed that TMT increased potassium leakage from the kidney, raised urine pH, and inhibited H(+)/K(+)-ATPase activity both in vitro and in vivo. In the tested animals, H(+)/K(+)-ATPase activity was positively correlated with the decrease of plasma K(+) and blood pH but was negatively correlated with the increase of urine K(+) and urine pH (P

To evaluated the manganese (Mn), cobalt (Co) and molybdenum (Mo) levels in blood and urine among general population in China, and thereby to analyze their prevalent features.From 2009 to 2010, a total of 18 120 subjects of general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland, by cluster random sampling method. The information about their living environment and health status were collected by questionnaire, and their blood and urine samples were also collected.Inductive coupled plasma mass spectrometry (ICP-MS) was applied to test the Mn, Co and Mo levels of blood and urine samples, and the Mn, Co, Mo distribution in blood and urine among groups of population in different ages and genders were then analyzed.Among general population in China, the geometric mean (GM) of Mn concentration in blood was 8.98 µg/L. The Mn concentration in blood among males and females were separately 8.14 µg/L and 9.88 µg/L (Z = -18.84, P0.01). The GM of Mn concentration in urine was 0.63 µg/L. The Mn concentration in urine among males and females were separately 0.62 µg/L and 0.63 µg/L (Z = -0.67, P0.05). The geometric mean (GM) of Co concentration in blood was 0.194 µg/L. The Co concentration in blood among males and females were separately 0.166 µg/L and 0.225 µg/L (Z = -23.04, P0.01). The GM of Co concentration in urine was 0.282 µg/L. The Co concentration in urine among males and females were separately 0.260 µg/L and 0.307 µg/L (Z = -7.35, P0.01). The GM of Mo concentration in blood was 0.25 µg/L. The Mo concentration in blood among male and female group were separately 0.27 µg/L and 0.23 µg/L (Z = -5.03, P0.01). The GM of Mo concentration in urine was 27.7 µg/L. The Mo concentration in urine among males and females were 29.8 µg/L and 25.6 µg/L (Z = -6.31, P0.01), respectively.The Mn, Co and Mo levels in blood and urine varied by gender and area among general population in China, the study provided basic data evidence for the following Mn, Co and Mo biological monitoring studies in near future.

To investigate the level of zinc (Zn) and copper (Cu) in whole blood among general population from 8 provinces in China, and to analyze the characteristics of distribution among different regions.This cross-sectional study was performed in 8 provinces from eastern, middle and western China between 2009 and 2010, including 13 110 subjects from 24 regions, and the blood and urine samples were collected. The ICP-MS was applied to test the content of ICP-MS in blood samples, and the results were used to analyze the characteristics of contents and distributions of Zn and Cu among population from different ages, genders and regions groups.Totally, the mean (95%CI) contents of Cu and Zn in blood were 795 (791-799)µg/L and 3 996(3 976-4 015) µg/L, respectively. The characteristics of distribution of Cu content were as followed, the content of males were lower than it of females (male:767 µg/L; female: 822 µg/L, t = -13.302, P0.01). The contents of blood Cu in groups of people aging 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were separately 860(853-868), 758(748-769), 734(728-734), 782(774-790), 811(795-827) and 820(815-826) µg/L. The differences showed statistical significance (F = 78.77, P0.01). The blood Cu content of people in eastern China (800µg/L) were also significantly higher than it in middle (774 µg/L)and western China (782 µg/L) (F = 10.94, P0.01). Distribution of blood Zn content showed characteristics as follows: the Zn content was higher in males than in females (male 4 085 µg/L and female 3 908 µg/L, t = 8.78, P0.01). The contents of blood Zn in groups of people aging 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were separately 3 306 (3 261-3 350), 3 888 (3 839-3 937), 3 948 (3 902-3 994), 4 272(4 228-4 315), 4 231(4 180-4 281) and 4 250 (4 205-4 294)µg/L, which showed significant statistical differences (F = 233.68, P0.01). The blood Zn content of people in eastern China (3 938 µg/L) were significantly lower than it in middle (4 237 µg/L)and western China (4 105 µg/L) (F = 53.16, P0.01). In addition, the study also compared the relation between content of Cu and Zn and the frequency of eating seafood. The results found that the frequency of eating seafood could influence the content of Cu and Zn (Cu: F = 13.54, P0.01; Zn: F = 200.20, P0.01).The contents and distributions of Cu and Zn in blood differs among people from different groups in ages, genders and regions. The baseline data of this study provided reliable scientific evidence for further research.

To evaluated the levels of arsenic (As) in blood and urine among general population in China and analyze its influencing factors.A total of 18 120 subjects from general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland from 2009 to 2010, by cluster random sampling method. Blood samples and urine samples were collected, the information of the life-style was collected by questionnaire.Inductive coupled plasma mass spectrometry was applied to test the As level in the samples, and the distribution of As in blood and urine for different ages, genders, areas and life habits were then analyzed.The geometric mean (GM) of blood As concentration among general population was 2.33 µg/L;the GM of blood As in male (2.35 µg/L) was higher than and female (2.30 µg/L) (Z = -1.42, P0.05); from eastern, central to western China, the blood As level were 2.94, 1.30 and 0.98 µg/L (χ(2) = 643.22, P0.05) , respectively; the GM in smokers (2.84 µg/L) was higher than non-smokers (2.27) (Z = -6.28, P0.05) ;the seafood consumer had a higher blood As level (2.59 µg/L) than people not consuming seafood (1.47 µg/L) (Z = -23.68, P0.05). The urine As level of the whole population was 13.72 µg/L;while its GM in male (14.10 µg/L) was higher than female (13.33 µg/L) (Z = -3.94, P0.05); the values from eastern, central to western China were 14.14, 16.02 and 9.57 µg/L (χ(2) = 353.89, P0.05), respectively;the level in smokers (16.06 µg/L) was higher than nonsmokers (13.70 µg/L) (Z = -2.63, P0.05); the level in seafood consumers (14.82 µg/L) was higher than people not consuming seafood (10.99 µg/L) (Z = -3.20, P0.05). The blood As level had a positive correlation with urine As level (correlation coefficient:0.285, P0.05).The As level in blood and urine varied by gender and area among general population in China, and related to life-styles. There was a positive correlation between As level in blood and that in urine.

To evaluate the levels of lead (Pb) and cadmium (Cd) in blood and urine among general population in China, and thereby analyze their prevalent features.A total of 18 120 subjects from general population aged 6-60 years were recruited from 24 districts in 8 provinces in eastern, central and western China mainland from 2009 to 2010, by cluster random sampling method. The blood samples and urine samples of these people were collected. The questionnaire survey was used to collect the information of the living environment and health conditions.Inductive coupled plasma mass spectrometry was applied to test the Pb and Cd levels in the samples, and the distribution of Pb and Cd in blood and urine for different ages, genders, areas and life habits were then analyzed.Among the general population in China, the geometric mean (GM) of blood Pb concentration was 34.9 µg/L; the GM of blood Pb in male and female groups were 40.1 and 30.4 µg/L (Z = -28.05, P0.05), respectively; the GM from eastern, central and western China were 31.2, 38.8 and 58.9 µg/L (χ(2) = 1 483.33, P0.05) , respectively. The GM of urine Pb of the whole population was 1.05 µg/L;while the GM in male and female groups were 1.06 µg/L and 1.05 µg/L (Z = -0.73, P0.05) , respectively;the values from eastern, central and western China were 0.76, 2.85 and 3.22 µg/L (χ(2) = 1 982.11, P0.05), respectively. The GM of blood Cd concentration among general population was 0.49 µg/L; and the values in male and female group were 0.60 and 0.41 µg/L (Z = -11.79, P0.05) , respectively; the GM from eastern, central and western China were 0.45, 0.65 and 0.67 µg/L (χ(2) = 69.87, P0.05), respectively; the GM of urine Cd concentration of the whole population was 0.28 µg/L, while the GM in male and female groups were 0.29 and 0.28 µg/L (Z = -3.86, P0.05), respectively; the values from eastern, central and western China were 0.29,0.42 and 0.18 µg/L (χ(2) = 402.76, P0.05), respectively. the Spearman's rank correlation coefficient for Cd in blood and Cd in urine was 0.22, for Pb in blood and Pb in urine was 0.21. Both the correlations were statistic significant (P0.05).The Pb and Cd levels in blood and urine were relatively higher among general population in China varying by gender and area. There were positive correlations between Pb and Cd levels in blood and those in urine.

Based on our investigation of hazelnut germplasm and Thompson's evaluation system for European hazelnuts, an in-depth study on character description of hazelnut germplasm was conducted from 1991 to 1994. Eighty characters were evaluated for the 58 tested species. It was found that eight characters should be eliminated from Thompson's system, such as annual branch length and hair, lentical color, and serration depth. The best leaf sampling position, sample volumes for quantitative characters, and scoring standards were also determined. Therefore, an advanced evaluation system for hazelnut germplasm was developed. The advanced system is easier and simpler, and will significantly expedite systematical studies of hazelnut germplasm.