Results 1 - 10 of 29900
Results 1 - 10 of 29900. Search took: 0.049 seconds
|Sort by: date | relevance|
[en] Over the past 30 years, there have been significant advancements in the field of nanomaterials. The possibility to use them in applications such as cancer treatment is extremely promising; however, the toxicity of many nanomaterials as well as the high costs associated with their use is still a concern. This paper aims to study the connection between nanomaterial toxicity and cost. This synergy may be interpreted as a different version of the classic “Prisoner's Dilemma” game, which in this case attempts to explain the possible outcomes of cooperation versus conflict between science advocating for the use of high-risk, possibly toxic materials due to their high returns, and society that might be dubious about the use of high-risk materials. In an effort to create diverse evaluation methodologies, this work uses a forecast horizon to evaluate the current status and expected future of the nanomaterials market. The historical progress of each market, toxicity information, and possible returns stemming from their use is taken into account to analyze the predictions. Our results suggest various trends for the associated costs and nanotoxicity of the studied materials.
[en] Within the project HISENTS, the sensor platform for nanotoxicity has been developed. Toxicity of nanoparticles is related to their concentration in the organ under consideration and time of exposure. Both, the concentration and exposure time, can be estimated from physiologically based pharmacokinetic (PBPK) modelling. The PBPK model enables to describe the ADME (absorption, distribution, metabolism, excretion) process and, hence, to predict the concentration of NPs in the organs and time of exposure. Application of the PBPK model is demonstrated on the treatment of in vivo distribution of PEGylated nanoparticles in rats. (authors)
[en] In situ characterisation of radio-toxic sludges and slurries is critical to numerous operations including those involving their transport and retrieval. An inexpensive, flexible acoustic backscatter system has been employed for the first time here to a 4/10. scale active storage tank comprising of a nuclear simulant suspension, to verify its application. Intricate suspension characteristics and tank operation features emerged. (authors)
[en] Lead is not an essential element for animals and plants. Furthermore, lead can be toxic and hazardous to human cell. The concentration of heavy metals were found to be greater in Mangrove areas than in Gulf coast areas. In this study, the lead contents of sediment solution were examined by flame atomic absorption spectroscopy (FASS). In this developing method, sample preparation was performed in three steps: digestion, ion exchange with Dowex 1x8 chloride form resin and extraction with 1 M sodium acetate. The contents of lead in sediment solution after pre-concentration were considerably higher than those in digested sediments in approximately 500 folds. The concentrations of lead were in the range of 76.10-96.53 ppm, and the precision of this method (%RSD) was 11.51
[en] Nanotechnology is a representative emerging technology in an embryonic stage. Due to the continuous support provided by both the public and private sectors of many countries, nanotechnologies have increasingly been commercialized in a wide array of industries, but also produce many commercialization failures. Tackling this problem, we investigate key factors affecting the commercialization of nanotechnologies. Identifying key factors of nanotechnology commercialization through literature review and interview with CEOs, we collected data of 206 Korean nanotechnology-based companies, and analyzed the causal relationship between key factors and financial performance. Logistic and Tobit regression models are used. Overall, companies achieving successful commercialization hold some common characteristics including consistent exploratory R and D, governmental funding, and nano-instrument/energy/environment-related products. Also, the use of potentially toxic materials makes commercialization difficult even if the products are not toxic.
[en] We address the problem of enhancing the sensitivity of biosensors to the influence of toxicants, with an entropy method of analysis, denoted as CASSANDRA, recently invented for the specific purpose of studying non-stationary time series. We study the specific case where the toxicant is tetrodotoxin. This is a very poisonous substance that yields an abrupt drop of the rate of spike production at t∼170 min when the concentration of toxicant is 4 nanomoles. The CASSANDRA algorithm reveals the influence of toxicants 30 min prior to the drop in rate at a concentration of toxicant equal to 2 nanomoles. We argue that the success of this method of analysis rests on the adoption of a new perspective of complexity, interpreted as a condition intermediate between the dynamic and the thermodynamic state
[en] Present article is devoted to chemical substances as a risk factor on a human health. Danger of use various chemical, radioactive substances and cleaning agents in everyday life including washing, cleaning, disinfecting substances, materials, paints and varnishes, adhesives, solvents, insect control, pesticides, fertilizers, building materials, polymers, furniture has been considered. The main components of detergents have been defined.
[en] Workers involved in the processes of extraction, purification and manufacture of uranium of nuclear plants are occupationally exposed to both natural and enriched uranium. Several chelating agents (TIRON, EDTA, BAI, etc.) have been tested in terms of their capacity to sequester uranium before it reaches its target organs. Our laboratory has studied a first generation biphosphonate, ethane-1-hydroxy-1,1-biphosphonate (EHBP). We have shown that treatment with EHBP induces survival rates of 75% and 100% in adult and suckling rats respectively intoxicated with an intraperitoneal injection of uranyl nitrate. There are no data available to date on the renal function following treatment with EBHP to counteract the toxic effects of an oral lethal dose of uranyl nitrate. The aim of the present study was to assay creatininemia and uremia as end-points to assess renal function. The results obtained reveal that the alterations in renal function induced by oral uranyl nitrate intoxication can be reduced at 48 hours and reverted at 14 days by subcutaneous or oral administration of EHBP. (author)
[en] Exposure to the environmental contaminant dioxin, elicits a variety of responses, which includes tumor promotion, embryotoxicity/teratogenesis, and carcinogenesis in both animals and humans. Many of the effects of dioxin are mediated by the aryl hydrocarbon receptor (AHR), a ligand-activated bHLH (basic helix-loop-helix)/PAS transcription factor. We initiated this study to determine whether dioxin's tumor-promoting activities may lie in its ability to alter proliferation, differentiation, and/or senescence using normal human epidermal keratinocytes (HEKs). Here, we report that dioxin appears to accelerate differentiation as measured by flow cytometry and by increased expression of the differentiation markers involucrin and filaggrin. In addition, dioxin appears to increase proliferation as indicated by an increase in NADH/NADPH production and changes in cell cycle. Finally, dioxin decreases SA (senescence associated) β-galactosidase staining, an indicator of senescence, in the differentiating keratinocytes. These changes were accompanied by decreases in the expression levels of key cell cycle regulatory proteins p53, p16INK4a, and p14ARF. Our findings support the idea that dioxin may exert its tumor-promoting actions, in part, by downregulating the expression levels of key tumor suppressor proteins, which may impair the cell's ability to maintain its appropriate cellular status