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1.
Nitrite intake from the consumption of cured meat and tap water was estimated for Finnish children of 1, 3 and 6 years as well as Finnish adults of 25–74 years. Nitrite content in the foods was measured by capillary electrophoresis, and was then used together with individual food consumption data from the FINDIET 2007 and DIPP studies in a stochastic exposure assessment by a Monte Carlo Risk Assessment (MCRA) program. Nitrite intake from additive sources and tap water was assessed, and more than every 10th child between the ages 3 and 6 years was estimated to have a nitrite intake exceeding the acceptable daily intake (ADI) of nitrite. The high exposure levels were caused by frequent consumption of large portions of sausages, up to 350 g day–1 or 750 g in 3 days, among the children. Median nitrite intake from cured meat was 0.016, 0.040, 0.033 and 0.005 mg kg–1 body weight day–1 for children of 1, 3 and 6 years and adults, respectively. Bayesian estimation was employed to determine safe consumption levels of sausages and cold cuts for children, and these results gave rise to new national food consumption advice.  相似文献   
2.
Mechanical clamping of a production part in production line measurement causes numerous functional problems in automotive industry quality control. It kills flexibility and brings non-value adding costs. Being able to mathematically model the effect of clamping to the part, these problems could be overcome. Empirical research using statistical and 3D-analysis show, that the effect of mechanical clamping can be estimated accurately with a locally linear model using finite element analysis. The accuracy of this mathematical estimate is sufficient for production line use. Experiments, supported by Daimler AG, have been done using a production line measurement system. Using a mathematical model to estimate the behavior of the measured part while clamped is called virtual clamping.  相似文献   
3.
Deregulation of telecommunication networks and utility companies has led to a worldwide increase in the use of fiber optic cables on long-span overhead power transmission lines. The cable jacket is subject to the deterioration caused by dry-band arcing, which is believed to be the major cause of failure of cable in service. This paper establishes an arc model based on the physical mechanism and experimental observation, and performs simulation of the transient of dry-band arcing on ADSS fiber optic cable. The basic theories concerning the dynamics of arc, arc extension along the electrolytic surface and its speed, and dry-band arcing on ADSS cable are reviewed. The differential equation systems composed of the dynamic equation of the arc and its interaction with the circuit components are proposed with state variable method. And the equations are solved numerically with Runge-Kutta method. The proposed differential equations can be used to simulate dry-band arcing on experimental setup in laboratory and predict the dynamic behavior of dry-band arcing on ADSS cable in transmission network. Hence the damage caused to cable can be evaluated. Experiments are performed to verify the simulation results.  相似文献   
4.
Here we demonstrate patterning of protein/quantum dot hybrid bionanostructures via electrostatic assembly of engineered negatively charged fluorescent protein with positively charged CdSe/ZnS QD patterns formed through e-beam lithography and post-patterning modification with cationic ligands.  相似文献   
5.
A prospective, open, multicentre study was performed to investigate the efficacy and safety of long-term treatment with cyclosporin in adults with severe atopic dermatitis. Subjects were treated for a maximum of 48 weeks. For the first 8 weeks, cyclosporin was administered at 2.5 mg/kg per day. The dose was then adjusted according to response. Disease activity was monitored using the six-area, six-sign score and the proportion of skin involved. Pruritus and sleep disturbance were assessed using four-point scales. Response was further evaluated on a five-point scale. Adverse events, blood pressure and serum biochemistry were monitored. Tolerability was assessed on a five-point scale. One hundred subjects were enrolled and 65 completed 48 weeks of treatment. Withdrawals occurred due to remission (three), inadequate response (seven), protocol violations (11) and adverse events (14, of which seven were probably treatment related). Cyclosporin produced rapid and highly significant improvements in all indices of disease activity. Sixty-five subjects considered that they had shown a considerable improvement or complete clearance of disease. Most patients relapsed after cessation of treatment, but neither signs nor symptoms had returned to baseline severity 8 weeks later. Blood pressure and serum creatinine levels increased slightly, and in one subject renal impairment was a major factor contributing to withdrawal of the drug. Overall, 85 subjects rated the tolerability of cyclosporin as good or very good. The results indicate that cyclosporin has a place in the long-term treatment of severe atopic dermatitis provided that appropriate patients are selected and careful monitoring is performed.  相似文献   
6.
We studied the effects of cotinine, the major metabolite of nicotine, on nicotine-induced increase in [3H]phorbol dibutyrate binding, activation of protein kinase C and [3H]noradrenaline release in primary cultured bovine adrenal chromaffin cells. Cotinine (1 mM, 15 min.) and nicotine (10 microM, 5 min.) increased the [3H]phorbol binding by 100% and 150%, respectively. Both a short-term (10 min.) and a long-term (24 hr) pretreatment with cotinine inhibited the effect of nicotine. A 24 hr pretreatment with cotinine (1 mM) also reduced the nicotine-induced increase in membrane-bound protein kinase C activity. Cotinine pretreatment (10 min.) dose-dependently inhibited the release of [3H]noradrenaline induced by nicotine and dimethylphenylpiperazinium. Cotinine pretreatment did not reduce the [3H]noradrenaline release induced by high extracellular potassium (56 mM) or veratrine (10 mg l-1). The results indicate that cotinine inhibits activation of protein kinase C and noradrenaline release induced by nicotinic agonists in primary cultures of bovine adrenal chromaffin cells. The results suggest that pre-existing cotinine could modify responses to acute exposure to nicotine in neural systems.  相似文献   
7.
Expressions for the major variables in the general rate equation for solid-solid nucleation were developed on the basis of various models of the critical nucleus shape during homogeneous and heterogeneous nucleation. These models are based upon spheres, but in some a facet was incorporated at one boundary orientation to represent the presence of a partially or fully coherent structure. Gibbs’ relationship for the critical radius is applicable to all of the models. The other variables in the nucleation rate equation are affected by the model and by faceting. Reduction of AG* by faceting is concluded to be the primary cause for the presence of reproducible lattice orientation relationships and for the existence of transition phases during precipitation from solid solutions.  相似文献   
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9.
Laser coatings are frequently used in applications where they slide against various elastomeric and polymeric seals or guide bands in different environments. Examples of such applications include hydraulics, maritime propulsion systems and components in pulp & paper industry. In this study highly corrosion resistant Inconel 625 (DIN Mat. No. 2.4856) and Thermanit 2509 super duplex stainless steel (~1.4501) coatings manufactured by novel coaxial hot‐wire laser cladding technique are tested in dry conditions at room temperature against various composite polytetrafluoroethylene (PTFE) seals. Despite only small difference in coating surface hardness, ~1.4501 and 2.4856 show significant differences in wear and friction performance against various seals. For instance, ~1.4501 is superior to 2.4856 against glass fiber and MoS2 reinforced PTFE in terms of wear resistance and friction characteristics, whereas 2.4856 performs better against bronze reinforced PTFE seal. The reference Stellite laser coating, which is the hardest counter surface in this study, exhibits the best wear behavior against all the seal materials tested. The differences in wear performances are explained by cohesive and adhesive wear mechanisms.  相似文献   
10.
Metal Science and Heat Treatment - The results of experimental studies of the process of laser cladding with scanning with the help of a 15-kW fiber laser are presented. The surface layers are...  相似文献   
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