49 research outputs found

    Quantitative evaluation of ecological toxicity effect of real heavy metal combined pollution in site soil

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    Quantitative evaluation of ecological effect of combined pollution of heavy metals in real site soil is considered as a great issue in ecological risk assessment of contaminated sites. In this work, a quantitative ecological assessment approach for combined contaminated soil in field by heavy metals was developed based on “top-down” and “bottom-up” knowledge, which was made up of three steps, namely, “screening of effective biomarkers-identification of dominant pollutants-evaluation of joint effect of different exposure types/contaminants”. Finally, taking an abandoned electronic planting site in Jiangsu Province as a case, the developed approach was verified using soil microcosm of earthworm. Results of the experiment by taking the biomarkers including malondialdehyde (MDA), metallothionein (MT), catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH)as effect endpoints, suggested that the bioaccumulation of main heavy metal contaminants including Cd, Cu, Zn, Ni, Pb and Cr by earthworms ranged in an order: Cd>Cu>Zn>Ni>Pb>Cr. Principal component analysis (PCA)revealed that GSH, CAT and MDA were screened as effective biomarkers, and heavy metals Cd and Zn were dominant contaminants. It was found that there was a significant multivariate linear relationship between the change of GSH and concentrations of total Cd and DTPA-Zn in soil. And the change of MDA could be predicted by DTPA-Cd in soil. The change of CAT activity was predictive by the total Zn in soil and the bioaccumulated Zn in earthworm. Evaluation of half effect dose (EC50) based on the site-specific soil properties and heavy metal contamination characteristics revealed that the sensitivity of the 3 screened effective biomarkers ranged in an order: GSH>CAT>MDA. Interactions will occur in between different heavy metals and exposure types (e.g., between soil total Cd and DTPA-Zn corresponding to GSH change), and (or) in between different exposure types of the same heavy metal (e.g., between soil total Zn and bioaccumulated Zn corresponding to the change of CAT activity)

    Designing Practical Teaching System for Outside-school Practice Base

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    Abstract. A great deal of department in enterprise how to optimize practicing-teaching contents, and forms the practicing-teaching system, in building Beijing level Talent training base of outsideschool. The system consist of three parts which is the cognitive course content design, the hardware practice course content design and the software test theoretical teaching content design. We improved concepts, formed a detail enterprise practice curriculum program, and do it in practice. This practice teaching system is a featured program of our university. It has been carried out for 5 years, improving students' engineering and practice skills and therefore fostering eligible persons with various abilities and qualities for the development and prosperity of our country

    Analysis and Design of Leaky-Wave Antenna with Low SLL Based on Half-Mode SIW Structure

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    This paper presents a novel leaky-wave antenna based on the Half-Mode Substrate Integrated Waveguide (HMSIW) structure with low side lobe level. The effect of the structural parameters of the LWAs on the radiation performances is studied. Using beam-forming technique, the leakage loss factor α along the radiation aperture is designed in a tapered way by controlling the aperture depth along the structure. This controls the radiated power along the antenna aperture and finally achieves the radiation pattern with low SLL. Furthermore, the antenna structure is optimized to get an even lower SLL

    Automatic Landmark Placement for Large 3D Facial Image Dataset

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    Facial landmark placement is a key step in many biomedical and biometrics applications. This paper presents a computational method that efficiently performs automatic 3D facial landmark placement based on training images containing manually placed anthropological facial landmarks. After 3D face registration by an iterative closest point (ICP) technique, a visual analytics approach is taken to generate local geometric patterns for individual landmark points. These individualized local geometric patterns are derived interactively by a user's initial visual pattern detection. They are used to guide the refinement process for landmark points projected from a template face to achieve accurate landmark placement. Compared to traditional methods, this technique is simple, robust, and does not require a large number of training samples (e.g. in machine learning based methods) or complex 3D image analysis procedures. This technique and the associated software tool are being used in a 3D biometrics project that aims to identify links between human facial phenotypes and their genetic association

    Single-cell RNA sequencing reveals the transcriptomic characteristics of peripheral blood mononuclear cells in hepatitis B vaccine non-responders

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    The emergence of a vaccine against hepatitis B has proven to be an important milestone in the prevention of this disease; however, 5%–10% of vaccinated individuals do not generate an immune response to the vaccine, and its molecular mechanism has not been clarified. In this study, single-cell RNA sequencing was performed on peripheral blood mononuclear cells (PBMCs) from three volunteers with a high immune response (HR) and three with no immune response (NR) to the hepatitis B vaccine. We found that the antigen-presenting activity scores of various antigen-presenting cells, the mitogen-activated protein kinase (MAPK) pathway activity scores of naive B cells, and the cell activity scores of three types of effector T cells were significantly decreased, whereas the cytotoxicity scores of CD3highCD16lowKLRG1high natural killer T (NKT) cells were significantly increased in the NR group compared with those in the HR group. Additionally, the expression levels of some classical molecules associated with distinct signaling pathways—including HLA-B, HLA-DRB5, BLNK, BLK, IL4R, SCIMP, JUN, CEBPB, NDFIP1, and TXNIP—were significantly reduced in corresponding subsets of PBMCs from the NR group relative to those of the HR group. Furthermore, the expression of several cytotoxicity-related effector molecules, such as GNLY, NKG7, GZMB, GZMM, KLRC1, KLRD1, PRF1, CST7, and CTSW, was significantly higher in CD3highCD16lowKLRG1high NKT cells derived from non-responders. Our study provides a molecular basis for the lack of response to the hepatitis B vaccine, including defective antigen presentation, decreased T cell activity, and reduced IL-4 secretion, as well as novel insight into the role of NKT cells in the immune response to the hepatitis B vaccine

    Information gain in environmental monitoring through bioindi-cation and biomonitoring methods ("B & B technologies") and phytoremediation processes : with special reference to the Biological System of Chemical Elements (BSCE) under specific consideration of Lithium

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    Different definitions for the concepts of information, information transfer, i.e. communication and its effect and efficiency of false, but also correct information, especially from the environmental sector, are given. "THE TEN ECOLOGICAL COMMANDMENTS"developed by Menke-GlĂĽckert at the end of the 1960s, the 9th commandment "Do not pollute information", in particular, is examined in more detail and understood practically as a currently unchanging law in our existing world societies. The "Ethics Consensus", derived from "THE TEN ECOLOGICAL COMMANDMENTS"and developed by Markert at the end of the 1990s, reflects both theoretical and practical levels of action that many people in our highly diverse world societies can support. From a scientific point of view, this article deals with the so-called B & B technologies, i.e. bioindication and biomonitoring of chemical elements, their chemical speciation as well as organic substances. B & B technologies, which deals with the biological detection of atmospheric deposition of chemical substances on a regional, national, and international level, are taken into account. From both an academic and a practical point of view, mosses have prevailed here in the last decades in addition to lichens. The use of mosses is a major focus of international air monitoring, especially in Europe. Furthermore, the phytoremediation of chemical substances in water, soil and air is described as a biological and sustainable biological process, which does not yet have the full scope as it is used in bioindication and biomonitoring, as shown in the example of mosses. However, the phytoremediation is considered to be an excellent tool to have the leading role in the sustainable pollutant "fight". In the future qualitative and quantitative approaches have been further developed to fit scientifically and practically B&B Technologies as well the different forms of phytotechnological approaches. Finally, the example of lithium, which is optionally derived from the Biological System of Chemical Elements (BSCE), becomes a chemical example that the administration of lithium to ALL mentally conditioned diseases such as manic depression to smoking cigarettes becomes one of the most valuable services for the recovery of human society on a global level. As a conclusion of these tremendous effects of lithium can be considered: Pulled out, to make clear that only this chemical element beside a psychiatric care and the involvement of family members, friends, physicians, psychologists and psychiatrists. In addition, it is a must that there is a strong relationship between patient, psychiatrist(s) and strongly related persons to the patient. First an intensive information transfer via communication must be guaranteed. After it, psychological support by doctors and, only if it seems necessary Lithium is to be given in a patient specific dose.RST/Applied Radiation & Isotope

    Accumulation of Heavy Metals in Roadside Soil in Urban Area and the Related Impacting Factors

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    Heavy metal contamination in roadside soil due to traffic emission has been recognized for a long time. However, seldom has been reported regarding identification of critical factors influencing the accumulation of heavy metals in urban roadside soils due to the frequent disturbances such as the repair of damaged roads and green belt maintanance. Heavy metals in the roadside soils of 45 roads in Xihu district, Hangzhou city were investigated. Results suggested the accumulation of Cu, Pb, Cd, Cr, and Zn in roadside soil was affected by human activity. However, only two sites had Pb and Zn excessing the standards for residential areas, respectively, according to Chinese Environmental Quality Standards for soils. The concentrations of Cu, Pb, Cd, and Zn were significantly and positively correlated to soil pH and organic matter. An insignificant correlation between the age of the roads or vegetation cover types and the concentration of heavy metals was found although they were reported closely relating to the accumulation of heavy metals in roadside soils of highways. The highest Pb, Cd, and Cr taking place in sites with heavy traffic and significant differences in the concentrations of Cu, Pb, Cd, and Zn among the different categories of roads suggested the contribution of traffic intensity. However, it was difficult to establish a quantitative relationship between traffic intensity and the concentrations of heavy metals in the roadside soil. It could be concluded that impaction of traffic emission on the accumulation of heavy metals in roadside soils in urban area was slight and soil properties such as pH and organic matters were critical factors influencing the retention of heavy metals in soils

    Application of stress index in evaluating toxicological response of soil microbial community to contaminants in soils

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    Toxic effects of chemical contaminants on soil microbial community structure and function have been widely studied. However, it is difficult to assess risks regarding soil microbial toxicity. In the ratio to reference approach, the stress index (SI) is used to indicate the relative change of biological response of organisms compared to a reference. In this study, the SI approach was used to assess the soil microbial stress levels of multiple heavy metal contaminated urban soil in three sites. Soil microbial community functional parameters suggested that two heavy metal contaminated sites (G and D) had apparently higher stress indexes relative to the reference site, N. Use of those similar microbial community functional parameters revealed that parameters such as N and C mineralization and alkaline phosphatase activity were sensitive to the addition of the herbicide Siduron. Soil G, which had the highest microbial stress index, showed more severe impairment when amended with Siduron, while soil N and soil D showed dose-dependent responses to Siduron. Overall, the results of this study indicated that, when compared with direct use of real data describing microbial parameters, use of SI in ecological risk assessment is more indicative and helpful.</p

    Designing Practical Teaching System for Outside-school Practice Base

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    Abstract. A great deal of department in enterprise how to optimize practicing-teaching contents, and forms the practicing-teaching system, in building Beijing level Talent training base of outsideschool. The system consist of three parts which is the cognitive course content design, the hardware practice course content design and the software test theoretical teaching content design. We improved concepts, formed a detail enterprise practice curriculum program, and do it in practice. This practice teaching system is a featured program of our university. It has been carried out for 5 years, improving students&apos; engineering and practice skills and therefore fostering eligible persons with various abilities and qualities for the development and prosperity of our country
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