980 resultados para North America--Maps.


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Three new species of Lumbriculidae were collected from floodplain seeps and small streams in southeastern North America. Some of these habitats are naturally acidic. Sylphella puccoon gen. n., sp. n. has prosoporous male ducts in X-XI, and spermathecae in XII-XIII. Muscular, spherical atrial ampullae and acuminate penial sheaths distinguish this monotypic new genus from other lumbriculid genera having similar arrangements of reproductive organs. Cookidrilus pocosinus sp. n. resembles its two subterranean, Palearctic congeners in the arrangement of reproductive organs, but is easily distinguished by the position of the spermathecal pores in front of the chaetae in X-XIII. Stylodrilus coreyi sp. n. differs from congeners having simple-pointed chaetae and elongate atria primarily by the structure of the male duct and the large clusters of prostate cells. Streams and wetlands of Southeastern USA have a remarkably high diversity of endemic lumbriculids, and these poorly-known invertebrates should be considered in conservation efforts.

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The eastern Steller sea lion (Eumetopias jubatus) population comprises animals that breed along the west coast of North America between California and southeastern Alaska. There are currently 13 major rookeries (>50 pups): five in southeastern Alaska, three in British Columbia, two in Oregon, and three in California. Overall abundance has increased at an average annual rate of 3.1% since the 1970s. These increases can largely be attributed to population recovery from predator-control kills and commercial harvests, and abundance is now probably as high as it has been in the last century. The number of rookeries has remained fairly constant (n=11 to 13) over the past 80 years, but there has been a northward shift in distribution of both rookeries and numbers of animals. Based on the number of pups counted in a population-wide survey in 2002, total pup production was estimated to be about 11,000 (82% in southeastern Alaska and British Columbia), representing a total population size as approximately 46,000−58,000 animal

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EXTRACT (SEE PDF FOR FULL ABSTRACT): Tree-ring chronologies, developed from cores from Pinyon pines growing on climatically sensitive sites in the north-central Great Basin, have been used to reconstruct precipitation and drought histories of the area from A.D. 1600 to 1982. Analysis of these hydrologic time series helps to place current climatic conditions into the perspective of the past 383 years (since 1600). ... The years 1934 and 1959 were the first and fourth driest while 1934 had the lowest July Palmer Drought Severity Index (PDSI) of the reconstructed records. Nevertheless, the decade of the 1930's is only the seventh driest since 1600; the decade 1953-1962 ranks as the second driest. The driest non-overlapping decade since 1600 was 1856-1865. Interestingly, the second wettest decade was 1932-1941. An examination of 30-year mean precipitation data shows that the driest 30-year period was 1871-1900; 1931-1960 ranks as the fourth driest. The current 30-year period (1951-1980) ranks twelfth.

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EXTRACT (SEE PDF FOR FULL ABSTRACT): The annual cycle and non-seasonal variability of streamflow over a network of stations in western North America and Hawaii is studied in terms of atmospheric forcing elements. The phase lag between the annual cycle of streamflow and precipitation varies considerably over this network, as does the persistence of monthly streamflow anomalies. This lag effect appears to be largely a function of the relative amount of snow laid down in a particular basin. In addition to the rather strong annual cycle that exists in mean streamflow and its variance at most of the stations, there is also a distinct annual cycle in the autocorrelation of streamflow anomalies that is related to the interplay between the temperature and precipitation annual cycles; of particular importance is the existence of stored water in the form of a snow pack.

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The extreme phases of the Southern Oscillation (SO) have been linked to fairly persistent classes of circulation anomalies over the North Pacific and parts of North America. It has been more difficult to uncover correspondingly consistent patterns of surface temperature and precipitation over much of the continent. The few regions that appear to have consistent SO-related patterns of temperature and precipitation anomalies are identified and discussed. Also discussed are regions that appear to have strong SO-related surface anomalies whose sign varies from episode to episode.

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Numerous integrated time series have been assembled that suggest global temperature has been increasing steadily over the last century. ... However, superimposed on the long-term warming trends of these series are decadal-scale fluctuations, periods of slightly increasing and even decreasing temperature followed by rapid increases in temperature. ... In this pilot study, data for 1931-1990 from eight [western North America] coastal stations are examined to test the utility of a state-space statistical model (developed by Dr. Roy Mendelssohn, PFEG) in separating and describing seasonal patterns and long-term trends.

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EXTRACT (SEE PDF FOR FULL ABSTRACT): Torrey pine (Pinus torreyana Parry ex Carr.) has one of the most limited geographical ranges and population size in the Pinus genus; it is present only on Santa Rosa Island and on the coast between San Diego and Del Mar, where our research was conducted. A 168-year chronology (1827-1994) was developed using 28 increment cores extracted from 15 living and 2 dead stranding trees at Torrey Pines State Reserve, San Diego, California. ... The spatial correlation with western North America winter and spring precipitation, as well as with published tree-ring chronologies, indicates a connection with the American Southwest. Global correlation maps with winter sea level pressure and sea surface temperature are consistent with the hypothesis that San Diego precipitation is affected by a southerly displaced North Pacific storm track and by warmer water farther south, both leading to higher transport of lower latitude moisture.

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The presumed pair relationships of intercontinental vicariad species in the Podophyllum group (Sinopodophyllum hexandrum vs. Podophyllum pelatum and Diphylleia grayi vs. D. cymosa) were recently, considered to be paraphyletic. In the present paper, the trnL-F and ITS gene sequences of the representatives were used to examine the sister relationships of these two vicariad species. A heuristic parsimony analysis based on the trnLF data identified Diphylleia as the basal clade of the other three genera, but provided poor resolution of their inter-relationships. High sequence divergence was found in the ITS data. ITS1 region, more variable but parsimonyuninformative. has no phylogenetic value, Sequence divergence of the ITS2 region provided abundant, phylogenetically informative variable characters. Analysis of ITS2 sequences confirmeda sister relationship between the presumable vicariad species, in spite of a low bootstrap support for Sinopodophyllum hexandrum vs. Podophyllum pelatum. The combined ITS2 and trnL-F data enforced a sister relationship between Sinopodophyllum hexandrum and Podophyllum pelatum with an elevated bootstrap support of 100%. Based on molecular phylogeny, the morphological evolution of this group was discussed. The self-pollination might have evolved from cross-fertilization two times in this group. The different pollination and seed dispersal systems of Sinopodophyllum hexandrum and Podophlyllum pelatum resulted from their adaptations to different ecological habitats. The divergence time of Sinopodophyllum hexandrum-Podophyllum pelatum is estimated to be 6.52+/-1.89 myr based on the ITS divergence. The divergence of this species pair predated or co-occurred with the recent uplift of the Himalayas 4-3 myr during the late Miocene and the formation of the alpine habitats. Sinopodophyllum hexandrum developed a host of specialized characters in its subsequent adaptation to the arid alpine surroundings. The present study confirmed the different patterns of species relationship between Asian-North American disjuncts. The isolation of plant elements between North America and eastern Asia must have been a gradual process, resulting in the different phylogenetic patterns and divergence times of the disjuncts.

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In this dissertation, we investigated two types of traveling ionospheric disturbances (TIDs)/gravity waves (GWs) triggered separately by auroral energy input during super geomagnetic storms and solar terminator (ST) under quiet geomagnetic conditions (kp<3+) using TEC measurements from the global network of GPS receivers. Research into the generation and propagation of TIDs/GWs during storms greatly enhance our understandings on the evolution processes of energy transportation from the high-latitude’s magnetosphere to the low-latitude ionosphere and the conjugated effect of TIDs propagation between the northern and southern hemispheres. Our results revealed that the conjugacy of propagation direction between the northern and southern hemispheres was subject to the influence of Coriolis force. We also figure out the evolution processes of ionospheric disturbances at the global scale. These are important topics that had not been well addressed previously. In addition, we also obtained thee wave structures of medium scale TIDs excited by the solar terminator (ST) moving over the northern America and physical mechanisms involved. Our observations confirm that the ST is a stable and repetitive source of ionospheric wave disturbances and the evidence of solar terminator generated disturbances has been demonstrated experimentally via the GPS TEC measurement. The main researches and results of this dissertation are as follows. First, the global traveling ionospheric disturbances (TIDs) during the drastic magnetic storms of October 29–31, 2003 were analyzed using the Global Position System (GPS) total electron content (TEC) data observed in the Asian-Australian, European and North American sectors. We collected the most comprehensive set of the TEC data from more than 900 GPS stations on the International GNSS Services (IGS) website and introduce here a strategy that combines polynomial fitting and multi-channel maximum entropy spectral analysis to obtain TID parameters. Moreover, in collaboration with my thesis advisor, I have developed an imaging technique of 2-dimensional map of TIDs structures to obtain spatial and temporal maps of large scale traveling ionospheric disturbances (LSTIDs). The clear structures of TEC perturbations map during the passage of TIDs were displayed. The results of our study are summarized as follows: (1) Large-scale TIDs (LSTIDs) and medium-scale TIDs (MSTIDs) were detected in all three sectors after the sudden commencement (SC) of the magnetic storm, and their features showed longitudinal and latitudinal dependences. The duration of TIDs was longer at higher latitudes than at middle latitudes, with a maximum of about 16 h. The TEC variation amplitude of LSTIDs was larger in the North American sector than in the two other sectors. At the lower latitudes, the ionospheric perturbations were more complicated, and their duration and amplitude were relatively longer and larger. (2) The periods and phase speeds of TIDs were different in these three sectors. In Europe, the TIDs propagated southward; in North America and Asia, the TIDs propagated southwestward; in the near-equator region, the disturbances propagated with the azimuth (the angle of the propagation direction of the LSTIDs measured clockwise from due north with 0°) of 210° showing the influence of Coriolis force; in the Southern Hemisphere, the LSTIDs propagated conjugatedly northwestward. Both the southwestward and northeastward propagating LSTIDs are found in the equatorial region. These results mean that the Coriolis effect cannot be ignored for the wave propagation of LSTIDs and that the propagation direction is correlated with the polar magnetic activity. (3) The day (day of year: 301) before the SC (sudden commencement) of magnetic storm, we observed a sudden TEC skip disturbances (±10 TECU). It should be a response for the high flux of proton during the solar flare event, but not the magnetic storms. Next, the most comprehensive and dense GPS network’s data from North-America region were used in this paper to analyze the medium scale traveling ionospheric disturbances (MSTIDs) which were generated by the moving solar terminator during the quiet days in 2005. We applied the multi-channel maximum entropy spectral analysis to calculated TID parameters, and found that the occurrence of ST-MSTIDs depends on the seasonal variations. The results of our study are summarized as follows: (1) MSTIDs stimulated by the moving ST (ST-MSTIDs) are detected at mid-latitudes after the passage of the solar terminator with the life time of 2~3 hours and the variation amplitude of 0.2~0.8 TECU. Spectral analysis indicated that the horizontal wavelength, average period, horizontal phase velocity of the MSTIDs are around 300±150 km,150±80 m/s and 25±15 min, respectively. In addition, ST-MSTIDs have wave fronts elongating the moving ST direction and almost parallel to ST. (2) The statistical results demonstrate that the dusk MSTIDs stimulated by ST is more obvious than the dawn MSTIDs in summer. On the contrary, the more-pronounced dawn MSTIDs occurs in winter. (3) Further analysis indicates that the seasonal variations of ST-MSTIDs occurrence frequency are most probably related to the seasonal differences of the variations of EUV flux in the ionosphere region and recombination process during sunrise and sunset period at mid-latitudes. Statistical study of occurrence characteristics of TIDs using the GPS network in North-American and European during solar maximum, In conclusion, statistical studies of the propagation characteristics of TIDs, which excited by the two common origins including geomagnetic storms and moving solar terminator, were involved with global GPS TEC databasein this thesis. We employed the multichannel maximum entropy spectral analysis method to diagnose the characteristics of propagation and evolvement of ionospheric disturbances, also, the characteristics of their regional distribution and climatological variations were revealed by the statistic analysis. The results of these studies can improve our knowledge about the energy transfer in the solar-terrestrial system and the coupling process between upper and lower atmosphere (thermosphere-ionosphere-mesosphere). On the other hand, our results of the investigation on TIDs generated by particular linear origin such as ST are important for developing ionospheric irregularity physics and modeling the transionosphere radio wave propagation. Besides, the GPS TEC representation of the ST-generated ionospheric structure suggests a better possibility for investigating this phenomenon. Subsequently, there are scientific meaning of the result of this dissertation to deeply discuss the energy transfer and coupling in the ionosphere, as well as realistic value to space weather forecast in the ionosphere region.

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http://www.archive.org/details/upanddownnorth00crosrich

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http://www.archive.org/details/indianmissionson00tororich

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The Emerging Church Movement (ECM) is a primarily Western religious phenomenon, identifiable by its critical ‘deconstruction’ of ‘modern’ religion. While most prominent in North America, especially the United States, some of the most significant contributors to the ECM ‘conversation’ have been the Belfast-based Ikon Collective and one of its founders, philosopher Peter Rollins. Their rootedness in the unique religious, political and social landscape of Northern Ireland in part explains their position on the ‘margins’ of the ECM, and provides many of the resources for their contributions. Ikon’s development of ‘transformance art’ and its ‘leaderless’ structure raise questions about the institutional viability of the wider ECM. Rollins’ ‘Pyrotheology’ project, grounded in his reading of post-modern philosophy, introduces more radical ideas to the ECM conversation. Northern Ireland’s ‘Troubles’ and ‘marginal’ location provides the ground from which Rollins and Ikon have been able to expose the boundaries of the ECM and raise questions about just how far the ECM may go in its efforts to transform Western Christianity.

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The economic and social consequences of international trade agreements have become a major area of inquiry in development studies in recent years. As evidenced by the energetic protests surrounding the Seattle meeting of the World Trade Organization (WTO) in December 1999 and the controversy about China's admission to the WTO, such agreements have also become a focus of political conflict in both the developed and developing countries. At issue are questions of job gains and job losses in different regions, prices paid by consumers, acceptable standards for wages and working conditions in transnational manufacturing industries, and the quality of the environment. All these concerns have arisen with regard to the North American Free Trade Agreement (NAFTA) and can be addressed through an examination of changes in the dynamics of the apparel industry in the post-NAFTA period.1 In this book, we examine the evolution of the apparel industry in North America in order to address some of these questions as they pertain to North America, with an eye toward the broader implications of our findings. We also consider the countries of the Caribbean Basin and Central America, whose textile and apparel goods are now allowed to enter the U.S. market on the same basis as those from Canada and Mexico (Odessey 2000). © 2009 by Temple University Press. All rights reserved.

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The various contributions to this book have documented how NAFTA-inspired firm strategies are changing the geography of apparel production in North America. The authors show in myriad ways how companies at different positions along the apparel commodity chain are responding to the new institutional and regulatory environment that NAFTA creates. By making it easier for U.S. companies to take advantage of Mexico as a nearby low-cost site for export-oriented apparel production, NAFTA is deepening the regional division of labor within North America, and this process has consequences for firms and workers in each of the signatory countries. In the introduction to this book we alluded to the obvious implications of shifting investment and trade patterns in the North American apparel industry for employment in the different countries. In this concluding chapter we focus on Mexico in the NAFTA era, specifically the extent to which Mexico's role in the North American economy facilitates or inhibits its economic development. W e begin with a discussion of the contemporary debate about Mexico's development, which turns on the question of how to assess the implications of Mexico's rapid and pro-found process of economic reform. Second, we focus on the textile and apparel industries as sectors that have been significantly affected by changes in regulatory environments at both the global and regional levels. Third, we examine the evidence regarding Mexico's NAFTA-era export dynamism, and in particular we emphasize the importance of interfirm networks, both for making sense of Mexico's meteoric rise among apparel exporters and for evaluating the implications of this dynamism for development. Fourth, we turn to a consideration of the national political-economic environment that shapes developmental outcomes for all Mexicans. Although regional disparities within Mexico are profound, aspects of government policy, such as management of the national currency, and characteristics of the institutional environment, such as industrial relations, have nationwide effects, and critics of NAFTA charge that these factors are contributing to a process of economic and social polarization that is ever more evident (Morales 1999; Dussel Peters 2000). Finally, we suggest that the mixed consequences of Mexico's NAFTA-era growth can be taken as emblematic of the contradictions that the process of globalization poses for economic and social development. The anti-sweatshop campaign in North America is one example of transnational or crossborder movements that are emerging to address the negative consequences of this process. In bringing attention to the problem of sweatshop production in North America, activists are developing strategies that rely on a network logic that is not dissimilar to the approaches reflected in the various chapters of this book. © 2009 by Temple University Press. All rights reserved.