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991.
This paper examines Mexico’s output convergence across its 32 states for 1993–2006, a period including the start of NAFTA. Employing dynamic panel data methods, our estimates provide interesting new results. First, we find positive rates of output absolute convergence across Mexican regions: varying from 1.5% for the years 1993–2006 to 9.4% for the years 1996–2006. Second, trade, capital inflows and international migration exert positive effects on output per capita growth. Third, rolling panels suggest the Border-North region faces increasing output convergence speed (from 8.9 to 11.2%), while the South-Center experiences a declining trend (from 12 to 7.6%) more recently.  相似文献   
992.
As part of the European Mercury Emissions from Chlor Alkali Plants (EMECAP) project, we tested the hypothesis that contamination of ambient air with mercury around chlor alkali plants using mercury cells would increase the internal dose of mercury in people living close to the plants. Mercury in urine (U-Hg) was determined in 225 individuals living near a Swedish or an Italian chlor alkali plant, and in 256 age- and sex-matched individuals from two reference areas. Other factors possibly affecting mercury exposure were examined. Emissions and concentrations of total gaseous mercury (TGM) around the plants were measured and modeled. No increase in U-Hg could be demonstrated in the populations living close to the plants. This was the case also when the comparison was restricted to subjects with no dental amalgam and low fish consumption. The emissions of mercury to air doubled the background level, but contributed only about 2 ng/m(3) to long-term averages in the residential areas. The median U-Hg levels in subjects with dental amalgam were 1.2 microg/g creatinine (micro/gC) in Italy and 0.6 microg/gC in Sweden. In individuals without dental amalgam, the medians were 0.9 microg/gC and 0.2 microg/gC, respectively. The number of amalgam fillings, as well as chewing, fish consumption, and female sex were associated with higher U-Hg. The difference between the countries is probably due to higher fish consumption in Italy, demethylated methyl mercury (MeHg) being partly excreted in urine. Post hoc power calculations showed that if the background mercury exposure is low it may be possible to demonstrate an increase in U-Hg of as little as about 10 ng/m(3) as a contribution to ambient mercury from a point source.  相似文献   
993.
Kinetic and mechanistic investigations of progesterone reaction with ozone   总被引:1,自引:0,他引:1  
The removal of progesterone by ozone in aqueous solution was studied in this work. The absolute rate constant was evaluated and first by-products were identified. The reaction was studied in the 2.0-8.0 pH range and was found to be a second-order reaction, first-order relative to each compound concentration. The rate constant, determined by kinetic experiments in presence of an OH radical scavenger (tert-butanol), was independent of pH. The value was evaluated to be equal to 480+/-30 M(-1)s(-1) by two kinetic methods. Mass spectrometry analyses were performed to investigate primary degradation products generated by the reaction of ozone with progesterone. Two by-products were evidenced. According to these results, a degradation pathway of progesterone reacting with ozone was proposed.  相似文献   
994.
The Gustav‐Heinemann‐Bridge across the river Spree in the new centre of Berlin. Modern solutions for the dynamic problems of a slender superstructure. The Gustav‐Heinemann‐Pedestrian‐Bridge across the river Spree was constructed as a short connection between the area of government and parliament and the new Berlin Hauptbahnhof in the new center of Berlin, the Spreebogen area. The slender superstructure was a result of an expertise and right from the beginning it had to be looked at as a structure very susceptible to pedestrian‐ and wind‐induced oscillations. After specification of the structure and the urban situation the paper concerns with the calculation of the human‐ and wind‐induced vibration behavior as well as the design calculations of the vibration dampers. Finaly, to get a confirmation of the design results and the calculated dampers efficiency, the results of the essential in‐situ‐tests are presented.  相似文献   
995.
For the treatment of secondary hyperparathyroidism (HPTH-II) in dialysis patients and hypercalcemia in patients with parathyroid carcinoma. Calcimimetics are a new class of drugs approved in the European Community and the United States by the Food and Drug Administration that were designed to suppress parathyroid hormone (PTH) levels with a simultaneous reduction in serum calcium and phosphorus levels, and calcium phosphorus product (Ca x P). Hypocalcemia is a frequent finding during the correction phase of the HPTH-II with calcimimetics. By contrast, the appearance of a hypercalcemia has yet to be described. In this paper, we report a case of severe hypercalcemia of immobilization in a 40-year-old hemodialyzed woman treated by cinacalcet HCl for a severe HPTH-II (PTH>1,000 pg/mL). A kidney transplantation recipient 1983 to 1995, she was diagnosed with Charcot-Marie Tooth disease in 1991. She had multiple orthopedic interventions for kidney-related osteoarticular problems probably favored by the kidney graft and the immunosuppressive treatment. While she was receiving the maximum dose of 180 mg/day of cinacalcet HCl and PTH at 443 pg/mL, she needed to be hospitalized for a right hip prothesis. Two weeks after the intervention she developed a symptomatic hypercalcemia of 3.57 mmol/L which was resistant to several measures including lowering the calcium concentration in the dialysate, withdrawing all vitamin D and calcium supplementation and the administration of calcitonin. Her serum calcium level was finally stabilized in the 2.37-2.95 mmol/L by administration of a single intravenous dose of pamidronate. This observation illustrates that the pharmacological activation of the parathyroid CaR and other putative CaR on bone cells by calcimimetics did not protect against the occurrence of hypercalcemia of immobilization favored by a severe HPTH-II in a hemodialysis patient.  相似文献   
996.
Steel fibre reinforced concrete (SFRC) is in many ways a well-known construction material, and its use has gradually increased over the last decades. The mechanical properties of SFRC are well described based on the theories of fracture mechanics. However, knowledge on other material properties, including the electrical resistivity, is sparse. Among others, the electrical resistivity of concrete has an effect on the corrosion process of possible embedded bar reinforcement and transfer of stray current. The present paper provides experimental results concerning the influence of the fibre volume fraction and the moisture content of the SFRC on its electrical resistivity. The electrical resistivity was measured by alternating current (AC) at 126 Hz. Moreover, an analytical model for the prediction of the electrical resistivity of SFRC is presented. The analytical model is capable of predicting the observed correlation between the fibre volume fraction and the electrical resistivity of the composite (the SFRC) for conductive fibres and moisture saturated concrete. This indicates that the steel fibres were conducting when measuring the electrical resistivity by AC at 126 Hz. For partly saturated concrete the model underestimated the influence of the addition of fibres. The results indicate that the addition of steel fibres reduce the electrical resistivity of concrete if the fibres are conductive. This represents a hypothetical case where all fibres are depassivated (corroding) which was created to obtain a conservative estimate on the influence of fibres on the electrical resistivity of concrete. It was observed that within typical ranges of variation the influence of the moisture content on the electrical resistivity was larger than the effect of addition of conductive steel fibres, but also that the relative impact on the electrical resistivity due to conductive steel fibres increased when the moisture content of the concrete was reduced.  相似文献   
997.
Although new technologies allow for less effort in prototyping, physical testing still remains an important step in the product development cycle. Well‐planned experiments are useful to guide the decision‐making process. During the design of an experiment, one of the challenges is to balance limited resources and system constraints to obtain useful information. It is common that prototypes are composed of several parts, with some parts more difficult to assemble than others. And, usually, there is only one piece available of each part type and a large number of different setups. Under these conditions, designs with randomization restrictions become attractive approaches. Considering this scenario, a new and additional criterion, minimum setup, to construct split‐plot type designs is presented. Designs with the minimum number of setups of the more difficult parts, which are especially useful for screening purposes in physical prototype testing, are discussed. The use of the proposed criterion combined with minimum aberration for selecting a regular design is shown through a real application in testing car prototypes. As a tool to practitioners, catalogs of selected 32‐run minimum setup minimum aberration split‐split‐plot and split‐split‐split‐plot designs are presented. More complete catalogs are available as Supporting information. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
998.
DNA replication is essential to maintain genome integrity in S phase of the cell division cycle. Accumulation of stalled replication forks is a major source of genetic instability, and likely constitutes a key driver of tumorigenesis. The mechanisms of regulation of replication fork progression have therefore been extensively investigated, in particular with DNA combing, an optical mapping technique that allows the stretching of single molecules and the mapping of active region for DNA synthesis by fluorescence microscopy. DNA linearization in nanochannels has been successfully used to probe genomic information patterns along single chromosomes, and has been proposed to be a competitive alternative to DNA combing. Yet this conjecture remains to be confirmed experimentally. Here, two complementary techniques are established to detect the genomic distribution of tracks of newly synthesized DNA in human cells by optical mapping in nanochannels. Their respective advantages and limitations are compared, and applied them to detect deregulations of the replication program induced by the antitumor drug hydroxyurea. The developments here thus broaden the field of applications accessible to nanofluidic technologies, and can be used in the future as part for molecular diagnostics in the context of high throughput cancer drug screening.  相似文献   
999.
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