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91.
Chile is one of the most seismically active countries in the world. Earthquakes are periodic phenomena that test the quality of construction, as well as the capacity of the population to adapt to sharp changes in socio-environ-mental conditions.
Experience in this regard has demonstrated the desirability of being prepared, at the institutional level and at the level of the general population, to carry out investigations and to begin measures to cope with these catastrophes, in order to reduce damage and the interruption of normal life to a minimum.
In this paper some general aspects of the social and health impacts of the earthquake of 3rd March 1985 are examined. The shock affected the central area of Chile which contains 61% of the total population.
The earthquake occurred at 19:50 hours on Sunday, 3rd March, and was of magnitude 7.8. Recorded personal losses included 180 dead and 2,575 injured, and around 200,000 damaged or destroyed dwellings. The destruction also affected the infrastructure of the public services, such as energy, road, telecommunications and water supply, giving rise to an emergency in the provision of assistance.
Special reference is made to the effects, on the health care infrastructure, drinking water supply and, less important, on the behavior of some communicable intestinal diseases that are highly endemic in the area under study.  相似文献   
92.
The theory of relativity has been considered as one of the most abstract and most difficult theories at the turn of the century. Today relativity is taught at high schools. This process is explained here by the increased faith in this theory and by better verbal explanations of the twin paradox and other effects of relativity. The development of new audiovisual aides for the teaching of relativity and other fields of modern physics is seen here as one of the main didactical challenges for the future.  相似文献   
93.
It is generally accepted that the bioavailability of metals in sediments is influenced by the presence of acid volatile sulfides (AVS). The pore water hypothesis predicts that, if the molar concentration of simultaneously extracted metals (SEM) in a sediment is smaller than the molar concentration of AVS, the free metal ion activity in the pore water is very small and that consequently no metal toxicity in short-term toxicity tests is observed. In this study we examined (1) if this concept can be extended to predict the absence of chronic Ni toxicity to the oligochaete deposit-feeding worm Lumbriculus variegatus and (2) if the organic carbon normalized excess SEM; i.e. [SEM-AVS]/f(OC) predicts the magnitude of Ni toxicity to L. variegatus. A 28-day toxicity experiment was performed in which biomass production of L. variegatus was determined in two natural sediments with different [AVS] and f(OC), spiked at different Ni concentrations. The absence of toxicity is predicted correctly by the [SEM-AVS]<0 criterion when only the 0-1 cm surface layer of the sediment is considered, but not when the whole bulk sediment is considered (0-3 cm). In both sediments, the same [SEM-AVS]/f(OC) at the surface corresponds with a similar decrease in L. variegatus biomass. Thus, [SEM-AVS]/f(OC) in the surface layer accurately predicts the magnitude of toxicity. This measure is therefore a good estimator of toxicologically available Ni. On the other hand, the free Ni(2+) ion activity in the overlying water appeared to be an equally good predictor of the magnitude of toxicity. Consequently, it was not possible to determine the relative importance of the overlying water and pore water exposure route with the semi-static laboratory experiments.  相似文献   
94.
This study seeks to advance our understanding of the leadership consequences that may ensue when supervisors and their teams have similar versus differing orientations toward the past. Integrating a leader–team fit perspective with functional leadership theory, we cast incongruence between supervisor and team past temporal focus as a key antecedent of supervisors' active (i.e., task-oriented and relationship-oriented) and passive (i.e., laissez-faire) leadership behaviors toward the team. We tested our hypotheses in a team-level study that included a field sample of 84 supervisors and their teams using polynomial regression and response surface analyses. Results illustrated that supervisors demonstrated more task-oriented and relationship-oriented leadership when supervisors' and their team's past temporal focus were incongruent rather than aligned. Furthermore, in situations of supervisor–team congruence, supervisors engaged in less task-oriented and relationship-oriented leadership and more laissez-faire leadership with higher (rather than lower) levels of supervisor and team past temporal focus. In sum, these findings support a complex (mis)fit model such that supervisors' attention to the past may hinder their productive leadership behaviors in some team contexts but not in others. Hence, this research advances a novel, multiple-stakeholder perspective on the role of both supervisors' and their team's past temporal focus for important leadership behaviors.  相似文献   
95.
In this paper, we develop a model to analyze the economics of carbon capture, transport, and storage (CCTS) in the wake of expected rising CO2 prices. We present a scalable mixed integer, multiperiod, welfare-optimizing network model for Europe, called CCTS-Mod. The model incorporates endogenous decisions on carbon capture, pipeline and storage investments, as well as capture, flow and injection quantities based on given costs, CO2 prices, storage capacities, and point source emissions. Given full information about future costs of CCTS-technology, and CO2 prices, the model determines a cost minimizing strategy on whether to purchase CO2 certificates, or to abate the CO2 through investments into a CCTS-chain on a site by site basis. We apply the model to analyze different scenarios for the deployment of CCTS in Europe, e.g., under high and low CO2 prices, respectively. We find that beyond CO2 prices of €50 per t, CCTS can contribute to the decarbonization of Europe’s industry sectors, as long as one assumes sufficient storage capacities (onshore and/or offshore). We find that CCTS is only viable for the power sector if the CO2 certificate price exceeds €75 per t.  相似文献   
96.
Periphyton colonization and sediment bioassessment were used ina survey to compare the relative environmental condition ofsampling sites located in Florida Bay and four peripheral sloughareas during the summer of 1995. Periphyton biomass, pigmentcontent, tissue quality and community composition weredetermined. In addition, benthic community composition and thetoxicities of whole sediments and associated pore waters weredetermined for two species of rooted macrophytes, an epibenthicinvertebrate and bioluminescent bacteria. Several locational differences were observed for the response parameters.Periphyton biomass was significantly greater in the Taylor Riverand the least in Shell Creek (P < 0.05). Most sediments were notacutely toxic to mysid shrimp nor phytotoxic. However, sedimentsfrom the Taylor River were more phytostimulatory than others (P< 0.05). Contaminant bioresidues were similar at most sites,however, mercury, chromium and nickel concentrations weregreater for periphyton colonized in the Taylor River and TroutCreek areas. Structural characteristics of the periphytic algalcommunity usually were statistically similar but a consistenttrend of lower density and diversity was evident for ShellCreek. The benthic community was the least diverse and dense inthe Canal C-111. The results of this study provide an initialindication of differences in the role of several slough areas aspossible sources of bioavailable contaminants to Florida Baywhich warrants additional investigation.  相似文献   
97.
The aim of this in vitro study was to examine the secretion activity, markers of proliferation and apoptosis in porcine ovarian granulosa cells (GCs) after deoxynivalenol (DON) addition. Ovarian granulosa cells were incubated with DON for 24h: 10, 100 and 1000 ng/mL, while the control group received no DON. The secretion of insulin-like growth factor I (IGF-I) and progesterone was determined by radioimmunoassay (RIA) and expression of cyclin B1, PCNA and caspase-3 by immunocytochemistry. IGF-I release by GCs was inhibited by DON, while progesterone release and the expression of cyclin B1 was stimulated by DON (at 1000 ng/mL but not at 10 and 100 ng/mL). PCNA expression was stimulated by DON (at 100 and 1000 ng/mL but not at 10 ng/mL). Caspase-3 expression was not influenced by DON treatment (at all doses). In conclusion, our results indicate, (1) a direct effect of DON on secretion of growth factor IGF-I and steroid hormone progesterone, (2) expression of markers of proliferation (cyclin B1 and PCNA) but not on the (3) expression of marker of apoptosis (caspase-3) in porcine ovarian granulosa cells. This in vitro study suggests the dose-dependent association of DON on porcine ovarian functions.  相似文献   
98.
A human subject exposure chamber, designed to hold six to eight subjects, coupled to an approximately 30-m3 Teflon reaction bag was designed and built to provide exposures that mimic the production and photochemical oxidation of atmospheric pollutants resulting from the combustion of coal or wood from a stove. The combustion products are introduced into the Teflon bag under atmospheric conditions. Photochemical oxidation of this mixture is accomplished by exposure to tropospheric sun-like radiation from an array of ultraviolet and black lamps. The aerosol in the Teflon reaction bag is then transferred into the exposure room to maintain a constant, lower exposure level. Continuous and semicontinuous monitoring of the gas and particulate matter (PM) pollution in the exposure room and the reaction bag is accomplished using a suite of instruments. This suite of instruments allows for the measurement of the concentrations of total and nonvolatile PM, nitric oxide, nitrogen dioxide, carbon monoxide, carbon dioxide, and ozone. The concentration of the particles was monitored by an R&P tapered element oscillating microbalance monitor. The chemical composition of the PM and its morphological characterization is accomplished by collecting samples in filter packs and conducting ion chromatography, elemental X-ray fluorescence, and scanning electron microscopy analyses. The concentration and composition of emissions from combustion of wood and coal is described. The results of this study suggest that although the bulk compositions of particulate emissions from the combustion of coal or wood in a stove have many similarities, the wood smoke aerosol is photochemically reactive, whereas the coal smoke aerosol is not.  相似文献   
99.
100.
Batch sorption experiments were carried out for the removal of cationic dyes (methylene blue and malachite green) from their aqueous solutions using sorbent made from fly ash-a waste material. Effects of various experimental parameters: initial dye concentration, contact time, pH, adsorbent dosage, solution temperature, surfactant addition and ionic strength on the fly ash sorption of dyes were evaluated. The isothermal data for sorption followed the Langmuir model. The maximum sorption capacity obtained for methylene blue and malachite green was 36.05 mg/g and 40.65 mg/g, respectively. Kinetic studies indicate that sorption on fly ash follows the pseudo-second order kinetics. Present research suggests that fly ash could be an appropriate adsorbent for the removal of basic dyes from aqueous solutions.  相似文献   
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