ABSTRACT Visibility degradation has become one of the major problems of public concern in Kaohsiung City as well as in most of the urban areas of Taiwan in recent years due to the increasing severity of smog. This study investigated the different aspects of atmospheric visibility degradation problems in metro Kaohsiung. First of all, both the long-term and short-term variation trends of atmospheric visibility were interpreted by analyzing the past data of prevailing visibility. Secondly, the correlation of atmospheric visibility with its major causative factors (i.e. meteorological and pollutant parameters) was established. Thirdly, the relationship between visibility degradation and aerosol mass/composition was derived by using multiple linear regression techniques based on in-situ field measurements of ambient aerosols and light extinction coefficient. Finally, the effective strategies for improving the visual air quality of metro Kaohsiung were proposed based on the results of the receptor-oriented modeling. In metro Kaohsiung, the seasonal variation of atmospheric visibility from the highest to the lowest were found to be in the sequence of summer, spring, autumn and winter, with mean values of 9.1, 8.2, 5.4, and 3.4 km, respectively. A diurnal variation of visibility was observed and showed that the visibility was generally lower in the morning and higher in the afternoon. A mass light scattering efficiency of 3.6 m2 g-1 for PM2.5 and a much lower value (0.3 m2 g-1) for PM2.5-10 indicated that the visible light was mainly scattered by the fine aerosol particles. The derived multiple linear regression model of light scattering coefficient yielded the mass scattering efficiencies of 4.6 m2 g-1 for (NH4)2SO4, 6.7 m2 g-1 for NH4NO3, 3.3 m2 g-1 for total carbon, and 3.2 m2 g-1 for PM2.5-remainder with an R2 of 0.97. On average, the percentage contributions of the visibility-degrading species to the light scattering coefficient were 29% for sulfates, 28% for nitrates, 22% for total carbon, and 21% for PM2.5-remainder, respectively. Furthermore, the major component of light extinction coefficient (bext) was the scattering of light by particles (75% of bext), followed by the absorption of light by particles (20%), while the remaining 5% of bext was attributed to gases. An empirical regression model of visibility based on sulfates, nitrates, PM2.5-remainder, and relative humidity was developed. The results showed that the variation of sulfate in PM2.5 aerosols was most sensitive to visibility change among the parameters. In terms of visibility degradation sources, source apportionment results indicated that the major contributors to fine particles were motor vehicle exhaust and secondary aerosols, which contributed more than half of the visibility degradation in metro Kaohsiung. Meanwhile, the second largest contributor was secondary aerosols containing ammonium sulfate and ammonium nitrate. Additionally, the contribution of soil dust increased markedly from normally only 4% to 25%, owing to an impact of continental dust storm from Mainland China. The results strongly indicated that soil dust blown from the desert areas of Northern China could be transported across the Yellow Sea and the East China Sea and evidently deposited in metro Kaohsiung. Results of the correlation analysis between atmospheric visibility and emission sources revealed a similarity between the source contribution pattern for visibility impairment and the source apportionment of fine particles. It showed ammonium sulfate contributed approximately 46% of the logarithm of atmospheric visibility, while the ¡§remainders¡¨, ammonium nitrate, and elemental carbons contributed about 20%, 17%, and 17%, respectively. Accordingly, this study concluded that the most effective strategy for improving atmospheric visibility in metro Kaohsiung was to prevent the formation of secondary fine particles containing ammonium sulfate and ammonium nitrate.

Texte remanié de: Th. doct.--Droit privé--Paris 2, 2002. / Bibliogr. p. 389-434. Index.

No description available.

This job point was make a computer program, by Pakstiene (Lithuania) and Solheim (Norway) method. Only by WET observed you could set comperable stars spectral classes, when are known programmable stars spectral class, and score extinction.

The experiments reported in this thesis attempted to examine the influence of thirst on the extinction of taste aversions in rats. Differences in the amount of stimulus exposure and deprivation state between groups were controlled for. The first experiment presented two novel flavours twelve times to rats when either thirsty or sated. A preference for the flavour presented when thirsty was established. The next three experiments examined whether this preference would accelerate the extinction of a taste aversion, by first pairing a novel flavour with lithium and then presenting the conditioned flavour when rats were either sated or thirsty. No evidence of accelerated extinction was found. The final two experiments examined whether the associatively-activated representation of sucrose could function to extinguish a taste-aversion to that sucrose without presenting sucrose itself. No evidence of representation-mediated extinction was found despite evidence that the context was associated with sucrose. The results indicate that the extinction of conditioned taste aversions is not influenced by counter-conditioning due to thirst relief, and extinction of such aversions appears to be due to similar processes as other forms of conditioning.

Thesis PlanB (M.S.)--University of Wisconsin--Stout, 2007. / Includes bibliographical references.

Abstract Globally, populations of several wader species are in decline. However, for most populations, information on abundance, its changes and the causes of declines is insufficient for designing successful management strategies to recover threatened populations. In this thesis I studied the status and population trends, nesting success, genetic structure and viability of a small, declining and threatened Temminck's stint population in the Bothnian Bay in the northern Baltic Sea. Historical population data, recent population counts in the early 1990s and in 1999–2002 and the demographic data showed that the decline is continuing, paralleled by declines in nesting success, recruitment and adult survival. Decline in nesting success was caused by a coincident increase in nest predation. Depredation was the main cause of nest losses. The common gull (Larus canus) and the ruddy turnstone (Arenaria interpres) were found to be the most important nest predators. I tested if an increase in nest concealment and consequent decrease in visibility lowers the efficiency of the early-departure antipredator behaviour of the species. An expected positive correlation emerged between visibility and flushing distance in the presence of alarm-giving birds, but not without them. This indicates that Temminck's stint exploits signals from other birds as early warning of an approaching predator. More nests were lost to predation on narrow than on wide shores. The nest predation rate was not related to habitat (natural vs. man-made) nor to differences in microhabitat characteristics associated with concealment. Overall variability of the mitochondrial control region was low in the one northeast Siberian and the three Fennoscandian populations studied. The occurrence of two maternal lineages in all Fennoscandian populations points to mixing of two previously isolated populations. The overall microsatellite genetic structuring (6 loci) in Fennoscandia was low. The pairwise comparison revealed a low but significant degree of differentiation between the Bothnian Bay and the two other Fennoscandian populations. However, no clear indication of genetic effects of small population size in the Bothnian Bay was detected. Matrix and Pradel-λ projection models, based on a ten year (1994–2003) capture-recapture data set, predicted a steep future decrease and a high risk of extinction within 50 years. Without immigration the decline would lead to extinction within 20 years. Population growth was the most sensitive to changes in adult survival, the rate of which declined during the study. Factors affecting adult survival most likely operate primarily during the non-breeding season in locations specific to the study population that are virtually unknown. Management efforts in the Bothnian Bay should, in addition to improving hatching success, first of all guarantee availability of wide, low-sward coastal breeding habitats for potential immigrants and recruits.

We report 95 vertebrate taxa (13 fishes, 11 reptiles, 63 birds, 8 mammals) from late Pleistocene bone deposits in Sawmill Sink, Abaco, The Bahamas. The >5,000 fossils were recovered by scuba divers on ledges at depths of 27-35 m below sea level. Of the 95 species, 39 (41%) no longer occur on Abaco (4 reptiles, 31 birds, 4 mammals).We estimate that 17 of the 39 losses (all of them birds) are linked to changes during the Pleistocene-Holocene Transition (PHT) (∼15-9 ka) in climate (becoming more warm and moist), habitat (expansion of broadleaf forest at the expense of pinewoodland), sea level (rising from -80 m to nearly modern levels), and island area (receding from ∼17,000 km2 to 1,214 km2). The remaining 22 losses likely are related to the presence of humans on Abaco for the past 1,000 y. Thus, the late Holocene arrival of people probably depleted more populations than the dramatic physical and biological changes associated with the PHT.

No description available.

Understanding the changes undergone during the life of an organism is often crucial to properly interpreting the evolutionary history of a group. For extinct organisms, this process can only be directly studied through growth series of fossils representing individuals at different stages of maturity. The growth patterns of the earliest dinosaurs (230–190 million years ago), in particular the morphological changes undergone during the life history of an individual (i.e., ontogeny) is poorly understood. To tackle this problem, I studied the changes undergone during growth of two early theropod dinosaurs, Coelophysis bauri and Megapnosaurus rhodesiensis. To reconstruct the growth of these dinosaurs I used ontogenetic sequence analysis (OSA). I found that, unlike living birds, early dinosaurs possessed an extremely high amount of intraspecific variation in growth. This variation had been previously interpreted as sexual difference; however, I found no evidence of this. Because this variation is widespread among early dinosaurs and their relatives, I hypothesize that this is the ancestral condition of dinosaurian growth, and that this was lost along the evolution to birds. These ontogenetic events are conserved through evolution, and I used this to assess the maturity of large Triassic theropods: I suggest that all known large-bodied Triassic theropods were still growing rapidly at death, and that the maximum body size of Triassic theropods was higher than previously supposed. Theropods were large before the end Triassic mass extinction, unlike what has been previously hypothesized. / Master of Science