WorldWideScience

Sample records for maya population decline

  1. Population structure of the Classic period Maya.

    Science.gov (United States)

    Scherer, Andrew K

    2007-03-01

    This study examines the population structure of Classic period (A.D. 250-900) Maya populations through analysis of odontometric variation of 827 skeletons from 12 archaeological sites in Mexico, Guatemala, Belize, and Honduras. The hypothesis that isolation by distance characterized Classic period Maya population structure is tested using Relethford and Blangero's (Hum Biol 62 (1990) 5-25) approach to R matrix analysis for quantitative traits. These results provide important biological data for understanding ancient Maya population history, particularly the effects of the competing Tikal and Calakmul hegemonies on patterns of lowland Maya site interaction. An overall F(ST) of 0.018 is found for the Maya area, indicating little among-group variation for the Classic Maya sites tested. Principal coordinates plots derived from the R matrix analysis show little regional patterning in the data, though the geographic outliers of Kaminaljuyu and a pooled Pacific Coast sample did not cluster with the lowland Maya sites. Mantel tests comparing the biological distance matrix to a geographic distance matrix found no association between genetic and geographic distance. In the Relethford-Blangero analysis, most sites possess negative or near-zero residuals, indicating minimal extraregional gene flow. The exceptions were Barton Ramie, Kaminaljuyu, and Seibal. A scaled R matrix analysis clarifies that genetic drift is a consideration for understanding Classic Maya population structure. All results indicate that isolation by distance does not describe Classic period Maya population structure. (c) 2006 Wiley-Liss, Inc.

  2. Regional response to drought during the formation and decline of Preclassic Maya societies

    Science.gov (United States)

    Ebert, Claire E.; Peniche May, Nancy; Culleton, Brendan J.; Awe, Jaime J.; Kennett, Douglas J.

    2017-10-01

    The earliest complex societies and a distinctive set of pan-regional social, political, and economic institutions appeared in the southern Maya lowlands during the Preclassic period (ca. 1200/1100 cal BCE-cal 300 CE). The timing of these cultural changes was variably influenced by local developments, interaction with other regions of Mesoamerica, and climate change. We present a high-resolution radiocarbon chronology for the growth of the early polity of Cahal Pech, Belize, one of the first permanent settlements in the southern Maya lowlands. We compare our results to a database containing over 1190 radiocarbon dates from cultural contexts reported from five major regions of the southern lowlands to interpret the expansion and decline of emerging complex social groups during the Preclassic. Comparisons to paleoclimate proxy datasets suggest that fluctuating climate regimes may have promoted alternating integration and fragmentation of early hierarchically organized societies. Stable climatic conditions during the Middle Preclassic (1000/900-300 cal BCE) fostered the centralization of populations and the formation of large regional polities across the southern lowlands. An extended drought at the end of the Late Preclassic (cal 150-300 CE) likely contributed to the decline of some major polities in the central Petén, but smaller sites located in productive environments were more resilient and persisted in to the Classic period. This research provides a framework for understanding the complex social and environmental factors that influenced localized adaptations to climate change and the episodic growth and decline of early complex societies in prehistory.

  3. Survey, Settlement, and Population History at the Ancient Maya Site of Pacbitun, Belize

    DEFF Research Database (Denmark)

    Healy, Paul F.; Helmke, Christophe G.B.; Awe, Jaime J.

    2007-01-01

    Survey and excavations of mounds on the outskirts of the site of Pacbitun in western Belize provide insights to the ancient Maya settlement pattern at this medium-sized regional center. This research employed two methods: analysis of structural remains from four separate 1000 m transect surveys...... to have been about 5000-6000 persons. This population estimate is compared with several coeval lowland Maya centers, and found to be reasonable for a medium-sized, Late Classic Maya center....

  4. Who fears and who welcomes population decline?

    Directory of Open Access Journals (Sweden)

    Hendrik P. Van Dalen

    2011-08-01

    Full Text Available European countries are experiencing population decline and the tacit assumption in most analyses is that the decline may have detrimental welfare effects. In this paper we use a survey among the population in the Netherlands to discover whether population decline is always met with fear. A number of results stand out: population size preferences differ by geographic proximity: at a global level the majority of respondents favors a (global population decline, but closer to home one supports a stationary population. Population decline is clearly not always met with fear: 31 percent would like the population to decline at the national level and they generally perceive decline to be accompanied by immaterial welfare gains (improvement environment as well as material welfare losses (tax increases, economic stagnation. In addition to these driving forces it appears that the attitude towards immigrants is a very strong determinant at all geographical levels: immigrants seem to be a stronger fear factor than population decline.

  5. NIDI scenario. Strong population decline in China

    OpenAIRE

    de Beer, J.A.A.

    2016-01-01

    United Nations projections assume that by the end of this century one third of the world population will live in India, China or Nigeria. While population growth in India will slow down and the population size of China will decline, population growth in Nigeria will accelerate. A new NIDI scenario projects less population growth in Nigeria and sharp population decline in China.

  6. Effects of harvest on the sustainability and leaf productivity of populations of two palm species in Maya homegardens.

    Science.gov (United States)

    Martínez-Ballesté, Andrea; Martorell, Carlos

    2015-01-01

    Traditional management practices are usually thought to be sustainable. The Maya manage Sabal (Arecaceae) palms in homegardens, using their leaves for thatching. The sustainability of such production systems depends on the long-term persistence of palm populations, whereas resource availability also depends on the number of leaves on individual palms. We examined how leaf harvest affects Sabal yapa and S. mexicana population growth rates (λ) and leaf production, comparing traditional and alternative harvest regimes in terms of sustainability and productivity. Demographic, harvest and leaf production data were recorded for three years in two homegardens. We used general integral projection models linked to leaf-production models to describe population dynamics and productivity. Harvest had no effect on S. yapa's vital rates or on λ, but it changed the growth rate of individuals of S. mexicana, with a negligible impact on λ. Homegardens affected λ values, reflecting the species' ecological affinities. S. mexicana, introduced from mesic forests, required watering and shade; therefore, its population declined rapidly in the homegarden that lacked both water and shade. The λ of the xerophilic S. yapa was slightly larger without watering than with watering. Palms usually compensated for leaf extraction, causing the number of leaves harvested per individual to increase with harvest intensity. Nevertheless, traditional management is relatively mild, allowing standing leaves to accumulate but reducing the homegarden's yield. Apparently, the Maya do not seek to maximize annual production but to ensure the availability of large numbers of leaves in homegardens. These leaves may then be used when the entire roof of a hut needs to be replaced every few years.

  7. Are snake populations in widespread decline?

    OpenAIRE

    Reading, C. J.; Luiselli, L. M.; Akani, G. C.; Bonnet, X.; Amori, G.; Ballouard, J. M.; Filippi, E.; Naulleau, G.; Pearson, D.; Rugiero, L.

    2010-01-01

    Long-term studies have revealed population declines in fishes, amphibians, reptiles, birds and mammals. In birds, and particularly amphibians, these declines are a global phenomenon whose causes are often unclear. Among reptiles, snakes are top predators and therefore a decline in their numbers may have serious consequences for the functioning of many ecosystems. Our results show that, of 17 snake populations (eight species) from the UK, France, Italy, Nigeria and Australia, 11 have declined ...

  8. NIDI scenario. Strong population decline in China

    NARCIS (Netherlands)

    de Beer, J.A.A.

    2016-01-01

    United Nations projections assume that by the end of this century one third of the world population will live in India, China or Nigeria. While population growth in India will slow down and the population size of China will decline, population growth in Nigeria will accelerate. A new NIDI scenario

  9. Are snake populations in widespread decline?

    Science.gov (United States)

    Reading, C J; Luiselli, L M; Akani, G C; Bonnet, X; Amori, G; Ballouard, J M; Filippi, E; Naulleau, G; Pearson, D; Rugiero, L

    2010-12-23

    Long-term studies have revealed population declines in fishes, amphibians, reptiles, birds and mammals. In birds, and particularly amphibians, these declines are a global phenomenon whose causes are often unclear. Among reptiles, snakes are top predators and therefore a decline in their numbers may have serious consequences for the functioning of many ecosystems. Our results show that, of 17 snake populations (eight species) from the UK, France, Italy, Nigeria and Australia, 11 have declined sharply over the same relatively short period of time with five remaining stable and one showing signs of a marginal increase. Although the causes of these declines are currently unknown, we suspect that they are multi-faceted (such as habitat quality deterioration, prey availability), and with a common cause, e.g. global climate change, at their root.

  10. Analysis of 16 autosomal STRs and 17 Y-STRs in an indigenous Maya population from Guatemala.

    Science.gov (United States)

    Cardoso, Sergio; Sevillano, Rubén; Illescas, María J; de Pancorbo, Marian Martínez

    2016-03-01

    The aim of this study was to contribute new data on autosomal STR and Y-STR markers of the Mayas from Guatemala in order to improve available databases of forensic interest. We analyzed 16 autosomal STR markers in a population sample of 155 indigenous Maya and 17 Y-chromosomal STR markers in the 100 males of the sample. Deviations from Hardy-Weinberg equilibrium and linkage disequilibrium between autosomal STR markers were not observed at any loci. The combined power of exclusion was estimated as 99.9991% and the combined power of discrimination was >99.999999999999%. Haplotype diversity of Y-STRs was calculated as 0.9984 ± 0.0018 and analysis of pairwise genetic distances (Rst) supported the Native American background of the population.

  11. [Economic growth with zero population growth and with declining population].

    Science.gov (United States)

    Kurz, R

    1982-05-01

    The effects of both zero population growth and a declining population on economic growth are considered. Although the neoclassical theory of economic growth leads to optimistic results in such cases, the author suggests that this theory cannot be used as a basis for political action. The need for further research into the economic effects of a stationary or declining population is stressed. (summary in ENG)

  12. Population, Rural Development, and Land Use Among Settler Households in an Agricultural Frontier in Guatemala’s Maya Biosphere Reserve

    Directory of Open Access Journals (Sweden)

    David Carr

    2009-11-01

    Full Text Available Guatemala was among the world’s leaders in deforestation during the 1990s at a rate of 2% per annum. Much of Guatemala’s recent forest loss has occurred in the emerging agricultural frontiers of the Maya Biosphere Reserve (MBR, the heart of the largest contiguous tropical forest in Central America—La Selva Maya. This paper presents data from 241 heads of households and 219 partners of household heads from a geographically stratified sample of eight (of 28 communities in the Sierra de Lacandón National Park (SLNP, the most ecologically biodiverse region in La Selva Maya and a core conservation zone of the MBR. Settler households are examined relative to a host of factors relating land use and land cover change. Specifically, demographic trends, political and socio-economic development, and ecological factors are described in this first detailed statistically-representative sample probing human population and environment interactions in an emerging agricultural frontier in Central America.

  13. Recent Advances in Maya Studies Using Remotely Sensed Data

    Science.gov (United States)

    Sever, Tom; Irwin, Daniel; Arnold, James E. (Technical Monitor)

    2001-01-01

    The Peten region of northern Guatemala is one of the last places on earth where major archeological sites remain to be discovered. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper and IKONOS satellite and airborne Star3i radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as cities, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the baJos, which are seasonally flooded swamps that cover over 40% of the land surface. The use of bajos for farming has been a source of debate within the professional community for many years. But the recent detection and verification of cultural features within the bajo system by our research team are providing conclusive evidence that the ancient Maya had adapted well to wetland environments from the earliest times and utilized them until the time of the Maya collapse. The combination of water management and bajo farming is an important resource for the future of the current inhabitants who are experiencing rapid population growth. Remote sensing imagery is also demonstrating that in the Preclassic period (600 BC- AD 250), the Maya had already achieved a high organizational level as evidenced by the construction of massive temples and an elaborate inter-connecting roadway system. Although they experienced several setbacks such as droughts and hurricanes, the Maya nevertheless managed the delicate forest ecosystem successfully for several centuries. However, around AD 800, something happened to the Maya to cause their rapid decline and eventual disappearance from the region. The evidence indicates that at this time there was increased climatic dryness, extensive deforestation, overpopulation, and widespread warfare. This raises a

  14. Mapping The Ancient Maya Landscape From Space

    Science.gov (United States)

    Sever, Tom; Arnold, James E. (Technical Monitor)

    2002-01-01

    The Peten region of northern Guatemala is one of the last places on earth where major archeological sites remain to be discovered. It was in this region that the Maya civilization began, flourished, and abruptly disappeared. Remote sensing technology is helping to locate and map ancient Maya sites that are threatened today by accelerating deforestation and looting. Thematic Mapper and IKONOS satellite and airborne Star3-I radar data, combined with Global Positioning System (GPS) technology, are successfully detecting ancient Maya features such as cities, roadways, canals, and water reservoirs. Satellite imagery is also being used to map the bajos, which are seasonally flooded swamps that cover over 40% of the land surface. The use of bajos for farming has been a source of debate within the professional community for many years. But the recent detection and verification of cultural features within the bajo system by our research team are providing conclusive evidence that the ancient Maya had adapted well to wetland environments from the earliest times and utilized them until the time of the Maya collapse. The use of the bajos for farming is also an important resource for the future of the current inhabitants who are experiencing rapid population growth. Remote sensing imagery is also demonstrating that in the Preclassic period (600 BC- AD 250), the Maya had already achieved a high organizational level as evidenced by the construction of massive temples and an elaborate inter-connecting roadway system. Although they experienced several setbacks such as droughts and hurricanes, the Maya nevertheless managed the delicate forest ecosystem successfully for several centuries. However, around AD 800, something happened to the Maya to cause their rapid decline and eventual disappearance from the region. The evidence indicates that at this time there was increased climatic dryness, extensive deforestation, overpopulation, and widespread warfare. This raises a question that

  15. Man and climate in the Maya lowlands

    Science.gov (United States)

    Leyden, Barbara W.

    1987-11-01

    A 15-m sedimentary core from Lake Salpeten provides the first complete Holocene sequence for the lowlying Peten District, Guatemala. Today, Lake Salpeten is a brackish, calcium sulfate lake near saturation surrounded by tropical semievergreen forest. The basal pollen record depicts sparse juniper scrub surrounding a lake basin that held ephermal pools and halophytic marshes. The lake rapidly deepened to > 27 m in the early Holocene and may have been meromictic, because nearly 2 m of gypsum "mush" was deposited. Mesic forests were quickly established and persisted until the Maya entered the district 3000 yr ago and caused extensive deforestation. Any climatic information contained in the pollen record of the Maya period is thus masked, but a regional pollen sequence linked to the archaeological record is substantiated because environmental disturbance was pervasive. Local intensification of occupation and population growth are seen as an increased deposition of pollen of agricultural weeds and colluviation into the lake, while the Classic Maya collapse is marked by a temporary decline in Compositae pollen. Effects of perturbations induced by the Maya persist in the pollen and limnetic record 400 yr after the Spanish conquest.

  16. Drought, agricultural adaptation, and sociopolitical collapse in the Maya Lowlands

    Science.gov (United States)

    Douglas, Peter M. J.; Pagani, Mark; Canuto, Marcello A.; Brenner, Mark; Hodell, David A.; Eglinton, Timothy I.; Curtis, Jason H.

    2015-01-01

    Paleoclimate records indicate a series of severe droughts was associated with societal collapse of the Classic Maya during the Terminal Classic period (∼800–950 C.E.). Evidence for drought largely derives from the drier, less populated northern Maya Lowlands but does not explain more pronounced and earlier societal disruption in the relatively humid southern Maya Lowlands. Here we apply hydrogen and carbon isotope compositions of plant wax lipids in two lake sediment cores to assess changes in water availability and land use in both the northern and southern Maya lowlands. We show that relatively more intense drying occurred in the southern lowlands than in the northern lowlands during the Terminal Classic period, consistent with earlier and more persistent societal decline in the south. Our results also indicate a period of substantial drying in the southern Maya Lowlands from ∼200 C.E. to 500 C.E., during the Terminal Preclassic and Early Classic periods. Plant wax carbon isotope records indicate a decline in C4 plants in both lake catchments during the Early Classic period, interpreted to reflect a shift from extensive agriculture to intensive, water-conservative maize cultivation that was motivated by a drying climate. Our results imply that agricultural adaptations developed in response to earlier droughts were initially successful, but failed under the more severe droughts of the Terminal Classic period. PMID:25902508

  17. Drought, agricultural adaptation, and sociopolitical collapse in the Maya Lowlands.

    Science.gov (United States)

    Douglas, Peter M J; Pagani, Mark; Canuto, Marcello A; Brenner, Mark; Hodell, David A; Eglinton, Timothy I; Curtis, Jason H

    2015-05-05

    Paleoclimate records indicate a series of severe droughts was associated with societal collapse of the Classic Maya during the Terminal Classic period (∼800-950 C.E.). Evidence for drought largely derives from the drier, less populated northern Maya Lowlands but does not explain more pronounced and earlier societal disruption in the relatively humid southern Maya Lowlands. Here we apply hydrogen and carbon isotope compositions of plant wax lipids in two lake sediment cores to assess changes in water availability and land use in both the northern and southern Maya lowlands. We show that relatively more intense drying occurred in the southern lowlands than in the northern lowlands during the Terminal Classic period, consistent with earlier and more persistent societal decline in the south. Our results also indicate a period of substantial drying in the southern Maya Lowlands from ∼200 C.E. to 500 C.E., during the Terminal Preclassic and Early Classic periods. Plant wax carbon isotope records indicate a decline in C4 plants in both lake catchments during the Early Classic period, interpreted to reflect a shift from extensive agriculture to intensive, water-conservative maize cultivation that was motivated by a drying climate. Our results imply that agricultural adaptations developed in response to earlier droughts were initially successful, but failed under the more severe droughts of the Terminal Classic period.

  18. Population dynamics and stock assessment for Octopus maya (Cephalopoda:Octopodidae fishery in the Campeche Bank, Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Francisco Arreguín-Sánchez

    2000-06-01

    Full Text Available The octopus (Octopus maya is one of the most important fish resources in the Mexican Gulf of Mexico with a mean annual yield of 9000 ton, and a reasonable number of jobs created; O. maya represents 80% of the total octopus catch, followed by Octopus vulgaris. There are two artisanal fleets based on Octopus maya and a middle-size fleet that covers both species. Catch-at-length structured data from the artisanal fleets, for the 1994 season (August 1st to December 15th were used to analyze the O. maya population dynamics and stock and to estimate the current level of exploitation. Von Bertalanffy growth parameters were: L = 252 mm, mantle length; K=1.4 year -1; oscillation parameters C=1.0, WP=0.6; and tz=0.842 years. A rough estimate of natural mortality was M=2.2, total mortality from catch curve Z=8.77, and exploitation rate F/Z=0.75. This last value suggests an intensive exploitation, even when yield per recruit analysis indicates both fleets may increase the minimum legal size on about 10% to increase yields. The length-based VPA also shows that the stock is being exploited under its maximum acceptable biological limit. These apparently contradictory results are explained by biological and behavioral characteristics of this species. Because most females die after reproduction, a new gross estimation of natural mortality was computed as M=3.3. The new estimate of exploitation rate was F/Z=0.57. This new value coincides with results from the length-VPA and the Thompson and Bell methods, the former suggesting that a reduction of 20% in fishing mortality may provide larger yields. This fishery resource is fully exploited and current management measures must be revised to sustain and probably optimize yields.Octopus maya es uno de los recursos pesqueros más importantes del Golfo de México, con rendimientos anuales promedio de 9 000 t, y constituye el 80% de la captura total, seguido por O. vulgaris. En la pesquería participan dos flotas

  19. Population Genetic Aspects of Pollinator Decline

    Directory of Open Access Journals (Sweden)

    Laurence Packer

    2001-06-01

    Full Text Available We reviewed the theory of conservation genetics, with special emphasis on the influence of haplodiploidy and other aspects of bee biology upon conservation genetic parameters. We then investigated the possibility that pollinator decline can be addressed in this way, using two meta-analytical approaches on genetic data from the Hymenoptera and the Lepidoptera. First, we compared levels of heterozygosity between the orders. As has been found previously, the haplodiploid Hymenoptera had markedly lower levels of genetic variation than the Lepidoptera. Bees had even lower levels, and bumble bees, in particular, often seemed almost monomorphic genetically. However, the statistically confounding effects of phylogeny render detailed interpretation of such data difficult. Second, we investigated patterns of gene flow among populations of these insects. Hymenoptera were far more likely to show genetic effects of population fragmentation than are Lepidoptera, even at similar geographic distances between populations. The reduced effective population sizes resulting from haplodiploidy probably contributed to this result. The proportion of species with low levels of gene flow did not vary among the different taxonomic groups within the Hymenoptera.

  20. AMPHIBIAN DECLINE, ULTRAVIOLET RADIATION AND LOCAL POPULATION ADAPTATION

    Science.gov (United States)

    Amphibian population declines have been noted on both local and global scales. Causes for these declines are unknown although many hypotheses have been offered. In areas adjacent to human development, loss of habitat is a fairly well accepted cause. However in isolated, seemingl...

  1. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    Science.gov (United States)

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  2. Kax and kol: Collapse and resilience in lowland Maya civilization

    Science.gov (United States)

    Dunning, Nicholas P.; Beach, Timothy P.; Luzzadder-Beach, Sheryl

    2012-01-01

    Episodes of population loss and cultural change, including the famous Classic Collapse, punctuated the long course of Maya civilization. In many cases, these downturns in the fortunes of individual sites and entire regions included significant environmental components such as droughts or anthropogenic environmental degradation. Some afflicted areas remained depopulated for long periods, whereas others recovered more quickly. We examine the dynamics of growth and decline in several areas in the Maya Lowlands in terms of both environmental and cultural resilience and with a focus on downturns that occurred in the Terminal Preclassic (second century Common Era) and Terminal Classic (9th and 10th centuries CE) periods. This examination of available data indicates that the elevated interior areas of the Yucatán Peninsula were more susceptible to system collapse and less suitable for resilient recovery than adjacent lower-lying areas. PMID:22371571

  3. Population, Rural Development, and Land Use Among Settler Households in an Agricultural Frontier in Guatemala’s Maya Biosphere Reserve

    OpenAIRE

    David Carr

    2009-01-01

    Guatemala was among the world’s leaders in deforestation during the 1990s at a rate of 2% per annum. Much of Guatemala’s recent forest loss has occurred in the emerging agricultural frontiers of the Maya Biosphere Reserve (MBR), the heart of the largest contiguous tropical forest in Central America—La Selva Maya. This paper presents data from 241 heads of households and 219 partners of household heads from a geographically stratified sample of eight (of 28) communities in the Sierra de Lacan...

  4. Autodesk Maya 2014 essentials

    CERN Document Server

    Naas, Paul

    2013-01-01

    The premiere book on getting started with Maya 2014 Whether you're just beginning, or migrating from another 3D application, this step-by-step guide is what you need to get a good working knowledge of Autodesk Maya 2014. Beautifully illustrated with full-color examples and screenshots, Autodesk Maya 2014 Essentials explains the basics of Maya as well as modeling, texturing, animating, setting a scene, and creating visual effects. You'll absorb important concepts and techniques, and learn how to confidently use Maya tools the way professionals do. Each chapter includes fun and cha

  5. Pesticides and Population Declines of California Alpine Frogs

    Science.gov (United States)

    Airborne pesticides from the Central Valley of California have been implicated as a cause for population declines of several amphibian species, with the strongest evidence for the mountain yellow-legged frog complex (Rana muscosa and R. sierrae) in the Sierra Nevada. We measured ...

  6. Dropping dead: causes and consequences of vulture population declines worldwide.

    Science.gov (United States)

    Ogada, Darcy L; Keesing, Felicia; Virani, Munir Z

    2012-02-01

    Vultures are nature's most successful scavengers, and they provide an array of ecological, economic, and cultural services. As the only known obligate scavengers, vultures are uniquely adapted to a scavenging lifestyle. Vultures' unique adaptations include soaring flight, keen eyesight, and extremely low pH levels in their stomachs. Presently, 14 of 23 (61%) vulture species worldwide are threatened with extinction, and the most rapid declines have occurred in the vulture-rich regions of Asia and Africa. The reasons for the population declines are varied, but poisoning or human persecution, or both, feature in the list of nearly every declining species. Deliberate poisoning of carnivores is likely the most widespread cause of vulture poisoning. In Asia, Gyps vultures have declined by >95% due to poisoning by the veterinary drug diclofenac, which was banned by regional governments in 2006. Human persecution of vultures has occurred for centuries, and shooting and deliberate poisoning are the most widely practiced activities. Ecological consequences of vulture declines include changes in community composition of scavengers at carcasses and an increased potential for disease transmission between mammalian scavengers at carcasses. There have been cultural and economic costs of vulture declines as well, particularly in Asia. In the wake of catastrophic vulture declines in Asia, regional governments, the international scientific and donor communities, and the media have given the crisis substantial attention. Even though the Asian vulture crisis focused attention on the plight of vultures worldwide, the situation for African vultures has received relatively little attention especially given the similar levels of population decline. While the Asian crisis has been largely linked to poisoning by diclofenac, vulture population declines in Africa have numerous causes, which have made conserving existing populations more difficult. And in Africa there has been little

  7. Human Population Decline in North America during the Younger Dryas

    Science.gov (United States)

    Anderson, D. G.; Goodyear, A. C.; Stafford, T. W., Jr.; Kennett, J.; West, A.

    2009-12-01

    There is ongoing debate about a possible human population decline or contraction at the onset of the Younger Dryas (YD) at 12.9 ka. We used two methods to test whether the YD affected human population levels: (1) frequency analyses of Paleoindian projectile points, and (2) summed probability analyses of radiocarbon (14C) dates. The results suggest that a significant decline or reorganization of human populations occurred at 12.9 ka, continued through the initial centuries of the YD chronozone, then rebounded by the end of the YD. FREQUENCY ANALYSES: This method employed projectile point data from the Paleoindian Database of the Americas (PIDBA, http://pidba.utk.edu). We tallied diagnostic projectile points and obtained larger totals for Clovis points than for immediately post-Clovis points, which share an instrument-assisted fluting technique, typically using pressure or indirect percussion. Gainey, Vail, Debert, Redstone, and Cumberland point-styles utilized this method and are comparable to the Folsom style. For the SE U.S., the ratio of Clovis points (n=1993) to post-Clovis points (n=947) reveals a point decline of 52%. For the Great Plains, a comparison of Clovis and fluted points (n=4020) to Folsom points (n=2527) shows a point decline of 37%, which may translate into a population contraction of similar magnitude. In addition, eight major Clovis lithic quarry sites in the SE U.S. exhibit little to no evidence for immediate post-Clovis occupations, implying a major population decline. SUMMED PROBABILITIES: This method involved calibrating relevant 14C dates and combining the probabilities, after which major peaks and troughs in the trends are assumed to reflect changes in human demographics. Using 14C dates from Buchanan et al. (2008), we analyzed multiple regions, including the Southeast and Great Plains. Contrary to Buchanan et al., we found an abrupt, statistically significant decline at 12.9 ka, followed 200 to 900 years later by a rebound in the number of

  8. Introducing Maya 2011

    CERN Document Server

    Derakhshani, Dariush

    2010-01-01

    A practical, step-by-step guide to Maya 2011. Four previous editions can't be wrong: this book is the perfect introduction to 3D and Maya. Learn to build and animate your own digital models and scenes with step-by-step instruction and fun and practical examples, while you draw inspiration from the striking examples included from talented Maya users. You'll create a simple animation of the planets in the solar system, learn to model a human hand and a decorative box?among other projects?and master all essential tools.: Provides a thorough, step-by-step introduction to Maya 2011; Explains the co

  9. Mastering Autodesk Maya 2013

    CERN Document Server

    Palamar, Todd

    2012-01-01

    Provides hands-on intermediate-to-advanced coverage of the leading 3D software Maya is the industry-leading 3D animation and effects software used in movies, visual effects, games, and other genres. For intermediate and advanced users who already know Maya basics, this official Maya guide provides the detailed coverage you need to unlock the software's more complex features. Elevate your skills in modeling, texturing, animation, and visual effects, and gain proficiency in high-level techniques for film, television, game development, and more. Artists who are already proficient in Maya basics

  10. Mastering Autodesk Maya 2012

    CERN Document Server

    Palamar, Todd

    2011-01-01

    The exclusive, official guide to the very latest version of Maya Get extensive, hands-on, intermediate to advanced coverage of Autodesk Maya 2012, the top-selling 3D software on the market. If you already know Maya basics, this authoritative book takes you to the next level. From modeling, texturing, animation, and visual effects to high-level techniques for film, television, games, and more, this book provides professional-level Maya instruction. With pages of scenarios and examples from some of the leading professionals in the industry, author Todd Palamar will help you master the entire CG

  11. Mastering Autodesk Maya 2011

    CERN Document Server

    Keller, Eric

    2010-01-01

    A beautifully-packaged, advanced reference on the very latest version of Maya. If you already know the basics of Maya, the latest version of this authoritative book takes you to the next level. From modeling, texturing, animation, and visual effects to high-level techniques for film, television, games, and more, this book provides professional-level Maya instruction. With pages of scenarios and examples from some of the leading professionals in the industry, this book will help you master the entire CG production pipeline.: Provides professional-level instruction on Maya, the industry-leading

  12. Climate change and pollution speed declines in zebrafish populations.

    Science.gov (United States)

    Brown, A Ross; Owen, Stewart F; Peters, James; Zhang, Yong; Soffker, Marta; Paull, Gregory C; Hosken, David J; Wahab, M Abdul; Tyler, Charles R

    2015-03-17

    Endocrine disrupting chemicals (EDCs) are potent environmental contaminants, and their effects on wildlife populations could be exacerbated by climate change, especially in species with environmental sex determination. Endangered species may be particularly at risk because inbreeding depression and stochastic fluctuations in male and female numbers are often observed in the small populations that typify these taxa. Here, we assessed the interactive effects of water temperature and EDC exposure on sexual development and population viability of inbred and outbred zebrafish (Danio rerio). Water temperatures adopted were 28 °C (current ambient mean spawning temperature) and 33 °C (projected for the year 2100). The EDC selected was clotrimazole (at 2 μg/L and 10 μg/L), a widely used antifungal chemical that inhibits a key steroidogenic enzyme [cytochrome P450(CYP19) aromatase] required for estrogen synthesis in vertebrates. Elevated water temperature and clotrimazole exposure independently induced male-skewed sex ratios, and the effects of clotrimazole were greater at the higher temperature. Male sex ratio skews also occurred for the lower clotrimazole exposure concentration at the higher water temperature in inbred fish but not in outbred fish. Population viability analysis showed that population growth rates declined sharply in response to male skews and declines for inbred populations occurred at lower male skews than for outbred populations. These results indicate that elevated temperature associated with climate change can amplify the effects of EDCs and these effects are likely to be most acute in small, inbred populations exhibiting environmental sex determination and/or differentiation.

  13. Maya Studio Projects Dynamics

    CERN Document Server

    Palamar, Todd

    2009-01-01

    The only hands-on book devoted to mastering Maya's dynamics tools for water, wind, and fire. In the world of animation, the ability to create realistic water, wind, and fire effects is key. Autodesk Maya software includes powerful dynamics tools that have been used to design breathtaking effects for movies, games, commercials, and short films. This professional guide teaches you the primary techniques you need to make the most of Maya's toolkit, so you'll soon be creating water that ripples, gusting winds and gentle breezes, and flickering fires the way Hollywood pros do. The one-of-a-kind boo

  14. Mastering Autodesk Maya 2014

    CERN Document Server

    Palamar, Todd

    2013-01-01

    Hands-on intermediate-to-advanced coverage of the leading 3D software Autodesk Maya is the industry-leading 3D animation and effects software used in movies, visual effects, games, and other genres. If you already know the basics of Maya and are ready to elevate your skills, then this book is for you. Nearly 1,000 pages are packed with organized, professional, and valuable insight on the leading 3D application on the market, enabling you to unlock the software's more complex features. Ideal as both a tutorial and study guide for the Autodesk Maya exam, this Autodesk Official Press

  15. Introducing Autodesk Maya 2012

    CERN Document Server

    Derakhshani, Dariush

    2011-01-01

    A practical, step-by-step guide to Maya 2012 This book is the ideal primer to getting started with Maya, the premier 3D animation and effects software used in movies, visual effects, games, cartoons, short films, and commercials. You'll learn the Maya interface and the basics of modeling, texturing, animating, and visual effects. Professional visual effects artist and instructor Dariush Derakhshani explains the nuances of the complex software, while creative tutorials offer realistic, professional challenges for those new to 3D. You'll be up and running in no time with the world's most popular

  16. [The decline in population growth, income distribution, and economic recession].

    Science.gov (United States)

    Banguero, H

    1983-05-01

    This work uses Keynesian principles and an analysis of the Colombian population in the 1970s to argue that the Colombian policy of slowing population growth, which was adopted with the aim of improving the general welfare of the population, has had shortterm negative effects on effective demand and thus on the level of employment and welfare. These negative effects were caused by the inflexibility of income distribution, which prevented expansion of the internal market, complicated by the stagnant condition of the external sector and the budget deficit. The results of the Colombian case study demonstrate how the deceleration of population growth beginning in the 1960s had a significant impact on the levels of consumption and savings and on the patterns of consumption, leading to low levels of investment and little dynamism. Although the current Colombian economic recession is aggravated by contextual factors such as the world economic recession, the high cost of capital, the industrial recession, and declining food production among others, at the core of the crisis are longer term structural determinants such as the decline in the rate of population growth and the highly unequal distribution of income and wealth, which have contributed to a shrinking of the internal market for some types of goods. Given the unlikelihood of renewed rapid population growth, the Keynesian model suggests that the only alternative for increasing aggregate demand is state intervention through public spending and investment and reorientation of the financial system to achieve a dynamic redistribution of income. Based on these findings and on proposals of other analysts, a stragegy for revitalization is proposed which would imply a gradual income redistribution to allow increased consumption of mass produced goods by the low income groups. Direct consumption subsidies would be avoided because of their inflationary and import-expanding tendencies; rather, incentives and support would be

  17. The Ancient Maya Landscape from Space

    Science.gov (United States)

    Sever, T.; Arnold, James E. (Technical Monitor)

    1999-01-01

    The Peten, once inhabited by a population of several million before the collapse of the ancient Maya in the 10th and 11th centuries, is being repopulated toward its former demographic peak. Environmental dynamics, however, impose severe constraints to further development. Current practices in subsistence, commercial agriculture, and cattle raising are causing rapid deforestation resulting in the destruction of environmental and archeological resources. The use of remote sensing and Geographic Information Systems (GIS) technology is a cost-effective methodology for addressing issues in Maya archeology as well as monitoring the environmental impacts being experienced by the current population.

  18. Addressing wild turkey population declines using structured decision making

    Science.gov (United States)

    Robinson, Kelly F.; Fuller, Angela K.; Schiavone, Michael V.; Swift, Bryan L.; Diefenbach, Duane R.; Siemer, William F.; Decker, Daniel J.

    2017-01-01

    We present a case study from New York, USA, of the use of structured decision making (SDM) to identify fall turkey harvest regulations that best meet stakeholder objectives, in light of recent apparent declines in abundance of wild turkeys in the northeastern United States. We used the SDM framework to incorporate the multiple objectives associated with turkey hunting, stakeholder desires, and region-specific ecological and environmental factors that could influence fall harvest. We identified a set of 4 fall harvest regulations, composed of different season lengths and bag limits, and evaluated their relative achievement of the objectives. We used a stochastic turkey population model, statistical modeling, and expert elicitation to evaluate the consequences of each harvest regulation on each of the objectives. We conducted a statewide mail survey of fall turkey hunters in New York to gather the necessary information to evaluate tradeoffs among multiple objectives associated with hunter satisfaction. The optimal fall harvest regulation was a 2-week season and allowed for the harvest of 1 bird/hunter. This regulation was the most conservative of those evaluated, reflecting the concerns about recent declines in turkey abundance among agency wildlife biologists and the hunting public. Depending on the region of the state, the 2-week, 1-bird regulation was predicted to result in 7–32% more turkeys on the landscape after 5 years. The SDM process provided a transparent framework for setting fall turkey harvest regulations and reduced potential stakeholder conflict by explicitly taking the multiple objectives of different stakeholder groups into account.

  19. FACTORS IMPLICATED IN AMPHIBIAN POPULATION DECLINES IN THE UNITED STATES

    Science.gov (United States)

    This study identified the factors responsible for the decline of native amphibians in the U.S. The type of land use, the introduction of exotic animal species, and chemical contamination were identified as the most likely causes of decline.

  20. Comparative metatranscriptomics reveals decline of a neustonic planktonic population

    KAUST Repository

    Mojib, Nazia; Thimma, Manjula; Kumaran, M.; Sougrat, Rachid; Irigoien, Xabier

    2016-01-01

    The neuston layer in tropical seas provides a good model to study the effects of increased levels of different stressors (e.g., temperature, ultraviolet radiation and Trichodesmium blooms). Here, we use a comparative in situ metatranscriptomics approach to reveal the functional genomic composition of metabolically active neustonic mesozooplankton community in response to the summer conditions in the Red Sea. The neustonic population exhibited changes in composition and abundance with a significant decline in copepods and appendicularia in July, when Trichodesmium cells were more abundant along with high temperatures and UV-B radiation. Nearly 23,000 genes were differentially expressed at the community level when the metatranscriptomes of the neustonic zooplankton were compared in April, July, and October. On a wider Phylum level, the genes related to oxidative phosphorylation, carbon, nucleotides, amino acids, and lipids were significantly overrepresented in both arthropods and chordates in April and October. On organism level for copepods, expression of genes responsive to oxidative stress, defense against bacteria, immune response, and virus reproduction were increased along with the observed increased appearance of copepod carcasses in the samples collected during July. The differences in expression correspond either to secondary effects of the Trichodesmium bloom or more likely to the increased UV-B radiation in July. Given the dearth of information on the zooplankton gene expression in response to environmental stimuli, our study provides the first transcriptome landscape of the mesozooplankton community during a period of increased mortality of the copepod and appendicularia population.

  1. Comparative metatranscriptomics reveals decline of a neustonic planktonic population

    KAUST Repository

    Mojib, Nazia

    2016-10-20

    The neuston layer in tropical seas provides a good model to study the effects of increased levels of different stressors (e.g., temperature, ultraviolet radiation and Trichodesmium blooms). Here, we use a comparative in situ metatranscriptomics approach to reveal the functional genomic composition of metabolically active neustonic mesozooplankton community in response to the summer conditions in the Red Sea. The neustonic population exhibited changes in composition and abundance with a significant decline in copepods and appendicularia in July, when Trichodesmium cells were more abundant along with high temperatures and UV-B radiation. Nearly 23,000 genes were differentially expressed at the community level when the metatranscriptomes of the neustonic zooplankton were compared in April, July, and October. On a wider Phylum level, the genes related to oxidative phosphorylation, carbon, nucleotides, amino acids, and lipids were significantly overrepresented in both arthropods and chordates in April and October. On organism level for copepods, expression of genes responsive to oxidative stress, defense against bacteria, immune response, and virus reproduction were increased along with the observed increased appearance of copepod carcasses in the samples collected during July. The differences in expression correspond either to secondary effects of the Trichodesmium bloom or more likely to the increased UV-B radiation in July. Given the dearth of information on the zooplankton gene expression in response to environmental stimuli, our study provides the first transcriptome landscape of the mesozooplankton community during a period of increased mortality of the copepod and appendicularia population.

  2. Practical Maya programming with Python

    CERN Document Server

    Galanakis, Robert

    2014-01-01

    ""Practical Maya Programming with Python"" is a practical tutorial packed with plenty of examples and sample projects which guides you through building reusable, independent modules and handling unexpected errors. If you are a developer looking to build a powerful system using Python and Maya's capabilities, then this book is for you. Practical Maya Programming with Python is perfect for intermediate users with basic experience in Python and Maya who want to better their knowledge and skills.

  3. UV-B Radiation Contributes to Amphibian Population Declines

    Science.gov (United States)

    Blaustein, Andrew

    2007-05-01

    UV-B (280-315 nm) radiation is the most significant biologically damaging radiation at the terrestrial surface. At the organismal level, UV-B radiation can slow growth rates, cause immune dysfunction and result in sublethal damage. UV-B radiation can lead to mutations and cell death. Over evolutionary time, UV radiation has been an important stressor on living organisms. Natural events, including impacts from comets and asteroids, volcanic activity, supernova explosions and solar flares, can cause large-scale ozone depletion with accompanying increases in UV radiation. However, these natural events are transient. Moreover, the amount of ozone damage due to natural events depends upon a number of variables, including the magnitude of the event. This is different from modern-day human-induced production of chlorofluorocarbons (CFCs) and other chemicals that deplete stratospheric ozone continuously, resulting in long-term increases in UV-B radiation at the surface of the earth. We will briefly review the effects of UV-B exposure in one group of aquatic organisms_amphibians. UV-B has been implicated as a possible factor contributing to global declines and range reductions in amphibian populations.

  4. POPULATION DECLINES OF THE PUERTO RICAN VIREO IN GUANICA FOREST.

    Science.gov (United States)

    JOHN FAABORG; KATE M. DUGGER; WAYNE J. ARENDT; BETHANY L. WOODWORTH; MICHAEL E. BALTZ

    1997-01-01

    Abundance of the Puerto Rican Vireo (Vireo Zutimeri) in Guanica Forest, Puerto Rico, has declined gradually over the period 1973-1996 as determined by constant effort mist netting. Concurrent studies of breeding vireos show low nesting success, primarily due to parasitism by Shiny Cowbirds (Molothrus bonariensis). This decline may reflect the rather recent entry of the...

  5. Land, Water and Society in the Maya Lowlands

    Science.gov (United States)

    Murtha, T.; French, K.; Duffy, C.; Webster, D.

    2013-12-01

    This paper reports the results of our project investigating the long-term spatial and temporal dynamics of land use management, agricultural decision-making and patterns of resource availability in the tropical lowlands of Central America. Overall, our project combines diachronic environmental simulation with historic settlement pattern survey to address a series of long-standing questions about the coupled natural and human (CNH) landscape history in the Central Maya lowlands (at the UNESCO world heritage site of Tikal in the Maya Biosphere Reserve). The paper describes the preliminary results of our project, including changing patterns of land, water, settlement and political history using climate, soil and hydrologic modeling and time series spatial analysis of population and settlement patterns. The critical period of the study, 1000 BC until the present, begins with dispersed settlements accompanied by widespread deforestation and soil erosion. Population size and density grows rapidly for 800 years, while deforestation and erosion rates decline; however, there is striking evidence of political evolution during this period, including the construction of monumental architecture, hieroglyphic monuments detailing wars and alliances, and the construction of a defensive earthwork feature, signaling political territories and possibly delineating natural resource boundaries. Population decline and steady reforestation followed until more recent migration into the region, which has impacted the biosphere ecology. Building on our previous research regionally and comparative research completed in Belize and Mexico, we are modeling sample periods the 3,000-year landscape history of the region, comparing land and water availability to population distributions and what we know about political history. Simulations are generated using historic climate and land use data, primarily relying on the Erosion Productivity Impact Calculator (EPIC) and the Penn State Integrated

  6. Autodesk Maya 2013 Essentials

    CERN Document Server

    Naas, Paul

    2012-01-01

    Recommnded text for those preparing for the Maya Associate exam Maya, the industry-leading 3D animation and effects software used in movies, games, cartoons, and commercials, is challenging to learn. This full-color guide features approachable, hands-on exercises and additional task-based tutorials that allow new users to quickly become productive with the program and familiar with its workflow in a professional environment. You'll learn the basics of modeling, texturing, animating, and lighting; explore different parts of the production pipeline; and practice on some real-world projects. Ma

  7. CAUSES AND CONSEQUENCES OF REGIONAL POPULATION DECLINE FOR PRIMARY SCHOOLS

    NARCIS (Netherlands)

    Haartsen, Tialda; Van Wissen, Leo

    During the past few years, the Dutch education system has been confronted with a sharp decline in the number of pupils. Especially in rural villages, inhabitants fear for the closure of their local primary school, which is perceived as a very negative development for local village life. This paper

  8. Reliability of genetic bottleneck tests for detecting recent population declines

    NARCIS (Netherlands)

    Peery, M. Zachariah; Kirby, Rebecca; Reid, Brendan N.; Stoelting, Ricka; Doucet-Beer, Elena; Robinson, Stacie; Vasquez-Carrillo, Catalina; Pauli, Jonathan N.; Palsboll, Per J.

    The identification of population bottlenecks is critical in conservation because populations that have experienced significant reductions in abundance are subject to a variety of genetic and demographic processes that can hasten extinction. Genetic bottleneck tests constitute an appealing and

  9. Nigeria's Population Policy and Future Fertility Decline | Mba ...

    African Journals Online (AJOL)

    The government of the Federal Republic of Nigeria, Africa's most populous country, promulgated its first explicit population policy in 1988, in response to the soaring population growth rate that impedes developmental efforts. The policy document has stipulated a number of quantitative demographic targets. Paramount ...

  10. The effects of declining population growth on the demand for housing.

    Science.gov (United States)

    Thomas C. Marcin

    1974-01-01

    Declining population growth and unprecedented changes in the age structure of the population in the next several decades will profoundly affect housing demand in the next 50 years. A decline in housing demand and substantial change in the type of housing in demand are likely to occur by 1990.

  11. The Role of Responses to Experiences of Rural Population Decline in the Social Capital of Families

    NARCIS (Netherlands)

    Elshof, Hans; Bailey, Ajay

    2015-01-01

    Population decline in rural areas has an impact on rural villages. This research investigates to what extent families with children in rural villages experience consequences of population decline, in which ways they respond to these experiences, and how that plays a role in their individual social

  12. Les Mayas à Hollywood.

    Directory of Open Access Journals (Sweden)

    Boris Jeanne

    2007-02-01

    Full Text Available Les Mayas de nos jours ce sont surtout des grandes pyramides au milieu de la forêt à un jet d’avion de Cancún : pour nombre de touristes américains et européens, c’est une occasion de s’acoquiner avec la culture, la grande culture des civilisations perdues, en continuant de boire des piña coladas le soir au bord de la plage. Et puis au mois de décembre les Mayas ont débarqué en force dans le paysage culturel local des Américains et des Européens, dans leurs cinémas, au moyen de deux films in...

  13. Increasing population and declining biological resources in the ...

    Indian Academy of Sciences (India)

    Unknown

    Biodiversity; global change; globalization; population and land use; sustainable ... School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110 067, India .... Ghat region to meet international market demands is an example ...

  14. Family planning, population policy and declining birth rates in Yugoslavia.

    Science.gov (United States)

    Malacic, J

    1989-01-01

    Although Yugoslavia has below-replacement fertility (a net reproduction rate in 1986 of 0.92), there are vast regional differentials. In the less developed autonomous province of Kosovo, for example, the population has doubled in the past 30 years. By region, the net reproduction rate ranges from a low of 0.83 in Croatia to a high of 1.80 in Kosovo. Until the late 1970s, when pronatalism and centralized economic planning had weakened in influence, there was an avoidance of demographic planning and policy. In 1975, the Federal Assembly issued a document on the country's demographic patterns and goals and called on republics and autonomous provinces to adapt the document to local situations--a step that was not taken. By the 1980s, the deteriorating political, economic, and demographic situation in regions with high fertility forced more explicit attention to the formulation of a national population policy. The 1989 Resolution on Population Development Policy and Family Planning sets the goal of replacement- level fertility for both high and low fertility regions and calls for an integrated approach to population issues and socioeconomic development. Decentralization, however, has represented a major obstacle to the execution of federal policy at the republic and lower local levels. While this is a chronic problem that must be addressed on the macro level, some progress could be achieved in problematic regions such as Kosovo through educational campaigns aimed at convincing individual couples of the advantages of family size of 2-3 children.

  15. Increasing population and declining biological resources in the ...

    Indian Academy of Sciences (India)

    Unknown

    Biodiversity; global change; globalization; population and land use; sustainable landscape management; traditional ecological management ... biodiversity on which they are dependant for their livelihood, there is an urgent need to explore additional pathways for ...... the upland central region of Mexico, as a response to.

  16. Is Declining malaria vector population in Africa a result of intervention Measures or sampling tools inefficiency?

    Directory of Open Access Journals (Sweden)

    Eliningaya Kweka

    2013-01-01

    Full Text Available Recent entomological surveys have shown a declining trend of malaria vector population in sub-Saharan Africa and the observation have beenassociated with the scale-up and intensive use of malaria intervention measures such as insecticides treated nets and insecticide residual sprays.However, little is known on the contribution of the mosquito sampling tools inefficiency on the declining trends of malaria vector population. Inthis commentary paper, we explore the possibility of contribution of mosquito sampling tools’ inefficiency to the observed declining trends ofmalaria vector population in Africa.

  17. Delineating genetic relationships among the Maya.

    Science.gov (United States)

    Ibarra-Rivera, Lisa; Mirabal, Sheyla; Regueiro, Manuela M; Herrera, Rene J

    2008-03-01

    By 250 AD, the Classic Maya had become the most advanced civilization within the New World, possessing the only well-developed hieroglyphic writing system of the time and an advanced knowledge of mathematics, astronomy and architecture. Though only ruins of the empire remain, 7.5 million Mayan descendants still occupy areas of Mexico, Guatemala, Belize, El Salvador, and Honduras. Although they inhabit distant and distinct territories, speak more than 28 languages, and have been historically divided by warfare and a city-state-like political system, and they share characteristics such as rituals, artistic, architectural motifs that distinguish them as unequivocally Maya. This study was undertaken to determine whether these similarities among Mayan communities mirror genetic affinities or are merely a reflection of their common culture. Four Mayan populations were investigated (i.e., the K'iche and Kakchikel from Guatemala and the Campeche and Yucatan from Mexico) and compared with previously published populations across 15 autosomal STR loci. As a whole, the Maya emerge as a distinct group within Mesoamerica, indicating that they are more similar to each other than to other Mesoamerican groups. The data suggest that although geographic and political boundaries existed among Mayan communities, genetic exchanges between the different Mayan groups have occurred, supporting theories of extensive trading throughout the empire. 2007 Wiley-Liss, Inc.

  18. Changes in land use as a possible factor in Mourning Dove population decline in Central Utah

    Science.gov (United States)

    Ostrand, William D.; Meyers, P.M.; Bissonette, J.A.; Conover, M.R.

    1998-01-01

    Mourning Dove (Zenaida macroura) population indices for the western United States have declined significantly since 1966. Based on data collected in 1951-1952, in Fillmore, Utah, we examined whether there had been a local decline in the dove population index since the original data were collected. We then determined whether habitat had been altered, identified which foraging habitats doves preferred, and assessed whether changes in land use could be responsible, in part, for a decline in the local population index. We found that dove population indices declined 72% and 82% from 1952-1992 and 1952-1993, respectively. The most dramatic change in habitat was an 82% decline in land devoted to dry land winter wheat production and a decline in livestock feed pens. Doves foraged primarily in harvested wheat fields, feed pens, and weedy patches. We hypothesize that a decrease in wheat availability during the spring and the consolidation of the livestock industry have contributed to a population decline of Mourning Doves in central Utah.

  19. Causes of mortality in California sea otters during periods of population growth and decline

    Science.gov (United States)

    Estes, J.A.; Hatfield, B.B.; Ralls, K.; Ames, J.

    2003-01-01

    Elevated mortality appears to be the main reason for both sluggish growth and periods of decline in the threatened California sea otter population. We assessed causes of mortality from salvage records of 3,105 beach-cast carcasses recovered from 1968 through 1999, contrasting two periods of growth with two periods of decline. Overall, an estimated 40%-60% of the deaths were not recovered and 70% of the recovered carcasses died from unknown causes. Nonetheless, several common patterns were evident in the salvage records during the periods of population decline. These included greater percentages of (1) prime age animals (3-10 yr), (2) carcasses killed by great white shark attacks, (3) carcasses recovered in spring and summer, and (4) carcasses for which the cause of death was unknown. Neither sex composition nor the proportion of carcasses dying of infectious disease varied consistently between periods of population increase and decline. The population decline from 1976 to 1984 was likely due to incidental mortality in a set-net fishery, and the decline from 1995 to 1999 may be related to a developing live-fish fishery. Long-term trends unrelated to periods of growth and decline included a decrease in per capita pup production and mass/length ratios of adult carcasses over the 31-yr study. The generally high proportion of deaths from infectious disease suggests that this factor has contributed to the chronically sluggish growth rate of the California sea otter population.

  20. High-precision radiocarbon dating of political collapse and dynastic origins at the Maya site of Ceibal, Guatemala.

    Science.gov (United States)

    Inomata, Takeshi; Triadan, Daniela; MacLellan, Jessica; Burham, Melissa; Aoyama, Kazuo; Palomo, Juan Manuel; Yonenobu, Hitoshi; Pinzón, Flory; Nasu, Hiroo

    2017-02-07

    The lowland Maya site of Ceibal, Guatemala, had a long history of occupation, spanning from the Middle Preclassic Period through the Terminal Classic (1000 BC to AD 950). The Ceibal-Petexbatun Archaeological Project has been conducting archaeological investigations at this site since 2005 and has obtained 154 radiocarbon dates, which represent the largest collection of radiocarbon assays from a single Maya site. The Bayesian analysis of these dates, combined with a detailed study of ceramics, allowed us to develop a high-precision chronology for Ceibal. Through this chronology, we traced the trajectories of the Preclassic collapse around AD 150-300 and the Classic collapse around AD 800-950, revealing similar patterns in the two cases. Social instability started with the intensification of warfare around 75 BC and AD 735, respectively, followed by the fall of multiple centers across the Maya lowlands around AD 150 and 810. The population of Ceibal persisted for some time in both cases, but the center eventually experienced major decline around AD 300 and 900. Despite these similarities in their diachronic trajectories, the outcomes of these collapses were different, with the former associated with the development of dynasties centered on divine rulership and the latter leading to their downfalls. The Ceibal dynasty emerged during the period of low population after the Preclassic collapse, suggesting that this dynasty was placed under the influence from, or by the direct intervention of, an external power.

  1. Identifying causes for population decline of the brown hare in agricultural landscapes in Denmark

    DEFF Research Database (Denmark)

    Jensen, Trine-Lee Wincentz

    In recent decades the brown hare (Lepus europaeus) population in Denmark has undergone a substantial decline, but proximate causes are unknown and little is known about actual densities. In this thesis, hare populations are investigated with respect to age composition and reproductive parameters...... proportions in game bags have dropped significantly since the 1950ies. Simple matrix population models with variable juvenile recruitment predict the similar population growth rates as actually observed in the annual bag records. The model substantiates the supposition that declines in the Danish hare...

  2. Entre velos: Maya para contrabajo

    OpenAIRE

    Rosa María Rodríguez Hernández

    2014-01-01

    Maya para contrabajo se materializa a partir de una imagen de Pepe Romero, cuyo texto interpreta a La decadencia de la mentira de Oscar Wilde. La estructura de Maya es binaria, especular y asimétrica; su poética obedece al juego verdad/mentira que subyace en la obra artística y en la vivencia del artista. Maya trae a la memoria las voces de los Upanishad, Schopenhauer, Shakespeare y Beethoven, influencias éstas en la obra de Wagner y, todas ellas, en la de Eliot. Los aspectos gestuales y visu...

  3. Maya Studio Projects Photorealistic Characters

    CERN Document Server

    Palamar, Todd

    2011-01-01

    Create realistic characters with Maya tools and this project-based book Maya character generation tools are extremely sophisticated, and there's no better way to learn all their capabilities than by working through the projects in this hands-on book. This official guide focuses on understanding and implementing Maya's powerful tools for creating realistic characters for film, games, and TV. Use a variety of tools to create characters from skeleton to clothing, including hairstyles and facial hair, and learn how to use Performance Capture. A DVD includes supplementary videos, project support fi

  4. Trapped in the extinction vortex? Strong genetic effects in a declining vertebrate population

    Directory of Open Access Journals (Sweden)

    Larsson Mikael

    2010-02-01

    Full Text Available Abstract Background Inbreeding and loss of genetic diversity are expected to increase the extinction risk of small populations, but detailed tests in natural populations are scarce. We combine long-term population and fitness data with those from two types of molecular markers to examine the role of genetic effects in a declining metapopulation of southern dunlins Calidris alpina schinzii, an endangered shorebird. Results The decline is associated with increased pairings between related individuals, including close inbreeding (as revealed by both field observations of parentage and molecular markers. Furthermore, reduced genetic diversity seems to affect individual fitness at several life stages. Higher genetic similarity between mates correlates negatively with the pair's hatching success. Moreover, offspring produced by related parents are more homozygous and suffer from increased mortality during embryonic development and possibly also after hatching. Conclusions Our results demonstrate strong genetic effects in a rapidly declining population, emphasizing the importance of genetic factors for the persistence of small populations.

  5. Dealing with China's future population decline: a proposal for replacing low birth rates with sustainable rates.

    Science.gov (United States)

    Cao, Shixiong; Wang, Xiuqing

    2009-09-01

    Decreasing population levels due to declining birth rates are becoming a potentially serious social problem in developed and rapidly developing countries. China urgently needed to reduce birth rates so that its population would decline to a sustainable level, and the family planning policy designed to achieve this goal has largely succeeded. However, continuing to pursue this policy is leading to serious, unanticipated problems such as a shift in the country's population distribution towards the elderly and increasing difficulty supporting that elderly population. Social and political changes that promoted low birth rates and the lack of effective policies to encourage higher birth rates suggest that mitigating the consequences of the predicted population decline will depend on a revised approach based on achieving sustainable birth rates.

  6. The ex-pat effect: presence of recent Western immigrants is associated with changes in age at first birth and birth rate in a Maya population from rural Guatemala.

    Science.gov (United States)

    McKerracher, Luseadra; Collard, Mark; Altman, Rachel; Richards, Michael; Nepomnaschy, Pablo

    2017-08-01

    Economic transitions expose indigenous populations to a variety of ecological and cultural challenges, especially regarding diet and stress. These kinds of challenges are predicted by evolutionary ecological theory to have fitness consequences (differential reproduction) and, indeed, are often associated with changes in fertility dynamics. It is currently unclear whether international immigration might impact the nature of such an economic transition or its consequences for fertility. To examine measures of fertility, diet and stress in two economically transitioning Maya villages in Guatemala that have been differentially exposed to immigration by Westerners. This study compared Maya women's ages at first birth and birth rates between villages and investigated whether these fertility indicators changed through time. It also explored whether the villages differed in relation to diet and/or a proxy of stress. It was found that, in the village directly impacted by immigration, first births occurred earlier, but birth rate was slower. In both villages, over the sampled time window, age at first birth increased, while birth rate decreased. The villages do not differ significantly in dietary indicators, but the immigration-affected village scored higher on the stress proxy. Immigration can affect fertility in host communities. This relationship between immigration and fertility dynamics may be partly attributable to stress, but this possibility should be evaluated prospectively in future research.

  7. Lion (Panthera leo) populations are declining rapidly across Africa, except in intensively managed areas

    OpenAIRE

    Bauer, Hans; Chapron, Guillaume; Nowell, Kristin; Henschel, Philipp; Funston, Paul; Hunter, Luke T. B.; Macdonald, David W.; Packer, Craig

    2015-01-01

    At a regional scale, lion populations in West, Central, and East Africa are likely to suffer a projected 50% decline over the next two decades, whereas lion populations are only increasing in southern Africa. Many lion populations are either now gone or expected to disappear within the next few decades to the extent that the intensively managed populations in southern Africa may soon supersede the iconic savannah landscapes in East Africa as the most successful sites for lion conservation. Th...

  8. Differential patterns of Batrachochytrium dendrobatidis infection in relict amphibian populations following severe disease-associated declines.

    Science.gov (United States)

    Whitfield, Steven M; Alvarado, Gilbert; Abarca, Juan; Zumbado, Hector; Zuñiga, Ibrahim; Wainwright, Mark; Kerby, Jacob

    2017-09-20

    Global amphibian biodiversity has declined dramatically in the past 4 decades, and many amphibian species have declined to near extinction as a result of emergence of the amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd). However, persistent or recovering populations of several amphibian species have recently been rediscovered, and such populations may illustrate how amphibian species that are highly susceptible to chytridiomycosis may survive in the presence of Bd. We conducted field surveys for Bd infection in 7 species of Costa Rican amphibians (all species that have declined to near extinction but for which isolated populations persist) to characterize infection profiles in highly Bd-susceptible amphibians post-decline. We found highly variable patterns in infection, with some species showing low prevalence (~10%) and low infection intensity and others showing high infection prevalence (>80%) and either low or high infection intensity. Across sites, infection rates were negatively associated with mean annual precipitation, and infection intensity across sites was negatively associated with mean average temperatures. Our results illustrate that even the most Bd-susceptible amphibians can persist in Bd-enzootic ecosystems, and that multiple ecological or evolutionary mechanisms likely exist for host-pathogen co-existence between Bd and the most Bd-susceptible amphibian species. Continued monitoring of these populations is necessary to evaluate population trends (continuing decline, stability, or population growth). These results should inform efforts to mitigate impacts of Bd on amphibians in the field.

  9. Decline of the Black Tern (Chlidonias niger) population in the Klamath Basin, Oregon, 2001-2010

    Science.gov (United States)

    Jaime L. Stephens; Sarah M. Rockwell; C. John Ralph; John D Alexander

    2015-01-01

    We monitored the Black Tern (Childonias niger) population at Agency and Upper Klamath Lakes, in the Klamath Basin, Oregon, from 2001–2010. We estimated that the population of adult Black Terns declined at these 2 joined waterbodies by 8.4% annually. In contrast, our analysis of Breeding Bird Survey data for the Bird...

  10. Growing hickories (Carya spp.) for roost trees: A method to support conservation of declining bat populations

    Science.gov (United States)

    Tara Luna; Daniel L. Lindner; R. Kasten Dumroese

    2014-01-01

    Bats (Vespertilionidae and Phyllostomidae) are a critically important component of North American ecosystems. These insectivorous mammals provide largely unrecognized ecosystem services to agriculture and forest health and sustain bat-dependent native plant populations. The decline of North American bat populations reflects the recent emergence of the fungal disease...

  11. Entre velos: Maya para contrabajo

    Directory of Open Access Journals (Sweden)

    Rosa María Rodríguez Hernández

    2014-01-01

    Full Text Available Maya para contrabajo se materializa a partir de una imagen de Pepe Romero, cuyo texto interpreta a La decadencia de la mentira de Oscar Wilde. La estructura de Maya es binaria, especular y asimétrica; su poética obedece al juego verdad/mentira que subyace en la obra artística y en la vivencia del artista. Maya trae a la memoria las voces de los Upanishad, Schopenhauer, Shakespeare y Beethoven, influencias éstas en la obra de Wagner y, todas ellas, en la de Eliot. Los aspectos gestuales y visuales de Maya entrelazan con la danza de Pina Bausch y con la retórica (hypotiposis.

  12. Glutathione S-transferase genotypes modify lung function decline in the general population: SAPALDIA cohort study

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    Ackermann-Liebrich Ursula

    2007-01-01

    Full Text Available Abstract Background Understanding the environmental and genetic risk factors of accelerated lung function decline in the general population is a first step in a prevention strategy against the worldwide increasing respiratory pathology of chronic obstructive pulmonary disease (COPD. Deficiency in antioxidative and detoxifying Glutathione S-transferase (GST gene has been associated with poorer lung function in children, smokers and patients with respiratory diseases. In the present study, we assessed whether low activity variants in GST genes are also associated with accelerated lung function decline in the general adult population. Methods We examined with multiple regression analysis the association of polymorphisms in GSTM1, GSTT1 and GSTP1 genes with annual decline in FEV1, FVC, and FEF25–75 during 11 years of follow-up in 4686 subjects of the prospective SAPALDIA cohort representative of the Swiss general population. Effect modification by smoking, gender, bronchial hyperresponisveness and age was studied. Results The associations of GST genotypes with FEV1, FVC, and FEF25–75 were comparable in direction, but most consistent for FEV1. GSTT1 homozygous gene deletion alone or in combination with GSTM1 homozygous gene deletion was associated with excess decline in FEV1 in men, but not women, irrespective of smoking status. The additional mean annual decline in FEV1 in men with GSTT1 and concurrent GSTM1 gene deletion was -8.3 ml/yr (95% confidence interval: -12.6 to -3.9 relative to men without these gene deletions. The GSTT1 effect on the FEV1 decline comparable to the observed difference in FEV1 decline between never and persistent smoking men. Effect modification by gender was statistically significant. Conclusion Our results suggest that genetic GSTT1 deficiency is a prevalent and strong determinant of accelerated lung function decline in the male general population.

  13. Fitness decline under osmotic stress in Caenorhabditis elegans populations subjected to spontaneous mutation accumulation at varying population sizes.

    Science.gov (United States)

    Katju, Vaishali; Packard, Lucille B; Keightley, Peter D

    2018-04-01

    The consequences of mutations for population fitness depends on their individual selection coefficients and the effective population size. An earlier study of Caenorhabditis elegans spontaneous mutation accumulation lines evolved for 409 generations at three population sizes found that N e   = 1 populations declined significantly in fitness whereas the fitness of larger populations (N e   = 5, 50) was indistinguishable from the ancestral control under benign conditions. To test if larger MA populations harbor a load of cryptic deleterious mutations that are obscured under benign laboratory conditions, we measured fitness under osmotic stress via exposure to hypersaline conditions. The fitness of N e   = 1 lines exhibited a further decline under osmotic stress compared to benign conditions. However, the fitness of larger populations remained indistinguishable from that of the ancestral control. The average effects of deleterious mutations in N e   = 1 lines were estimated to be 22% for productivity and 14% for survivorship, exceeding values previously detected under benign conditions. Our results suggest that fitness decline is due to large effect mutations that are rapidly removed via selection even in small populations, with implications for conservation practices. Genetic stochasticity may not be as potent and immediate a threat to the persistence of small populations as other demographic and environmental stochastic factors. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

  14. Effects of uncertainty and variability on population declines and IUCN Red List classifications.

    Science.gov (United States)

    Rueda-Cediel, Pamela; Anderson, Kurt E; Regan, Tracey J; Regan, Helen M

    2018-01-22

    The International Union for Conservation of Nature (IUCN) Red List Categories and Criteria is a quantitative framework for classifying species according to extinction risk. Population models may be used to estimate extinction risk or population declines. Uncertainty and variability arise in threat classifications through measurement and process error in empirical data and uncertainty in the models used to estimate extinction risk and population declines. Furthermore, species traits are known to affect extinction risk. We investigated the effects of measurement and process error, model type, population growth rate, and age at first reproduction on the reliability of risk classifications based on projected population declines on IUCN Red List classifications. We used an age-structured population model to simulate true population trajectories with different growth rates, reproductive ages and levels of variation, and subjected them to measurement error. We evaluated the ability of scalar and matrix models parameterized with these simulated time series to accurately capture the IUCN Red List classification generated with true population declines. Under all levels of measurement error tested and low process error, classifications were reasonably accurate; scalar and matrix models yielded roughly the same rate of misclassifications, but the distribution of errors differed; matrix models led to greater overestimation of extinction risk than underestimations; process error tended to contribute to misclassifications to a greater extent than measurement error; and more misclassifications occurred for fast, rather than slow, life histories. These results indicate that classifications of highly threatened taxa (i.e., taxa with low growth rates) under criterion A are more likely to be reliable than for less threatened taxa when assessed with population models. Greater scrutiny needs to be placed on data used to parameterize population models for species with high growth rates

  15. Lion (Panthera leo) populations are declining rapidly across Africa, except in intensively managed areas.

    Science.gov (United States)

    Bauer, Hans; Chapron, Guillaume; Nowell, Kristin; Henschel, Philipp; Funston, Paul; Hunter, Luke T B; Macdonald, David W; Packer, Craig

    2015-12-01

    We compiled all credible repeated lion surveys and present time series data for 47 lion (Panthera leo) populations. We used a Bayesian state space model to estimate growth rate-λ for each population and summed these into three regional sets to provide conservation-relevant estimates of trends since 1990. We found a striking geographical pattern: African lion populations are declining everywhere, except in four southern countries (Botswana, Namibia, South Africa, and Zimbabwe). Population models indicate a 67% chance that lions in West and Central Africa decline by one-half, while estimating a 37% chance that lions in East Africa also decline by one-half over two decades. We recommend separate regional assessments of the lion in the World Conservation Union (IUCN) Red List of Threatened Species: already recognized as critically endangered in West Africa, our analysis supports listing as regionally endangered in Central and East Africa and least concern in southern Africa. Almost all lion populations that historically exceeded ∼ 500 individuals are declining, but lion conservation is successful in southern Africa, in part because of the proliferation of reintroduced lions in small, fenced, intensively managed, and funded reserves. If management budgets for wild lands cannot keep pace with mounting levels of threat, the species may rely increasingly on these southern African areas and may no longer be a flagship species of the once vast natural ecosystems across the rest of the continent.

  16. Investigating Rates of Hunting and Survival in Declining European Lapwing Populations.

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    Guillaume Souchay

    Full Text Available Understanding effects of harvest on population dynamics is of major interest, especially for declining species. European lapwing Vanellus vanellus populations increased from the 1960s until the 1980s and declined strongly thereafter. About 400,000 lapwings are harvested annually and it is thus of high conservation relevance to assess whether hunting was a main cause for the observed changes in lapwing population trends. We developed a multi-event cause-specific mortality model which we applied to a long-term ring-recovery data set (1960-2010 of > 360,000 records to estimate survival and cause-specific mortalities. We found no temporal change in survival over the last 50 years for first-year (FY and older birds (after first-year; AFY originating from different ringing areas. Mean survival was high, around 0.60 and 0.80 for FY and AFY individuals, respectively. The proportion of total mortality due to hunting was <0.10 over the study period and the estimated proportion of harvested individuals (kill rate was <0.05 in each year. Our result of constant survival indicates that demographic processes other than survival were responsible for the pronounced change in lapwing population trends in the 1980s. Our findings lend support to the hypothesis that hunting was not a significant contributor to the large-scale decline of lapwing populations. To halt the ongoing decline of European lapwing populations management should focus on life history stages other than survival (e.g. productivity. Further analyses are required to investigate the contribution of other demographic rates to the decline of lapwings and to identify the most efficient conservation actions.

  17. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    Science.gov (United States)

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; Veblen, Thomas T; Smith, Jeremy M.; Kueppers, Lara M.

    2017-01-01

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively.Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers.Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forest and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine.Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.

  18. Population growth and the decline of natural Southern yellow pine forests

    Science.gov (United States)

    David B. South; Edward R. Buckner

    2004-01-01

    Population growth has created social and economic pressures that affect the sustainability of naturally regenerated southern yellow pine forests. Major causes of this decline include (1) a shift in public attitudes regarding woods burning (from one favoring it to one that favors fire suppression) and (2) an increase in land values (especially near urban centers). The...

  19. Population recovery following decline in an endangered stream-breeding frog (Mixophyes fleayi from subtropical Australia.

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    David Alan Newell

    Full Text Available Amphibians have undergone dramatic declines and extinctions worldwide. Prominent among these have been the stream-breeding frogs in the rainforests of eastern Australia. The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd has been postulated as the primary cause of these declines. We conducted a capture-mark-recapture study over a 7-year period on the endangered Fleay's barred frog (Mixophyes fleayi at two independent streams (30 km apart in order to assess the stability of these populations. This species had undergone a severe decline across its narrow geographic range. Mark-recapture modelling showed that the number of individuals increased 3-10 fold along stream transects over this period. Frog detection probabilities were frequently above 50% but declined as the populations increased. Adult survival was important to overall population persistence in light of low recruitment events, suggesting that longevity may be a key factor in this recovery. One male and female were present in the capture record for >6 years. This study provides an unambiguous example of population recovery in the presence of Bd.

  20. Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines

    OpenAIRE

    Ceballos, Gerardo; Ehrlich, Paul R.; Dirzo, Rodolfo

    2017-01-01

    The strong focus on species extinctions, a critical aspect of the contemporary pulse of biological extinction, leads to a common misimpression that Earth’s biota is not immediately threatened, just slowly entering an episode of major biodiversity loss. This view overlooks the current trends of population declines and extinctions. Using a sample of 27,600 terrestrial vertebrate species, and a more detailed analysis of 177 mammal species, we show the extremely high degree of population decay in...

  1. Endemic chronic wasting disease causes mule deer population decline in Wyoming.

    Directory of Open Access Journals (Sweden)

    Melia T DeVivo

    Full Text Available Chronic wasting disease (CWD is a fatal transmissible spongiform encephalopathy affecting white-tailed deer (Odocoileus virginianus, mule deer (Odocoileus hemionus, Rocky Mountain elk (Cervus elaphus nelsoni, and moose (Alces alces shirasi in North America. In southeastern Wyoming average annual CWD prevalence in mule deer exceeds 20% and appears to contribute to regional population declines. We determined the effect of CWD on mule deer demography using age-specific, female-only, CWD transition matrix models to estimate the population growth rate (λ. Mule deer were captured from 2010-2014 in southern Converse County Wyoming, USA. Captured adult (≥ 1.5 years old deer were tested ante-mortem for CWD using tonsil biopsies and monitored using radio telemetry. Mean annual survival rates of CWD-negative and CWD-positive deer were 0.76 and 0.32, respectively. Pregnancy and fawn recruitment were not observed to be influenced by CWD. We estimated λ = 0.79, indicating an annual population decline of 21% under current CWD prevalence levels. A model derived from the demography of only CWD-negative individuals yielded; λ = 1.00, indicating a stable population if CWD were absent. These findings support CWD as a significant contributor to mule deer population decline. Chronic wasting disease is difficult or impossible to eradicate with current tools, given significant environmental contamination, and at present our best recommendation for control of this disease is to minimize spread to new areas and naïve cervid populations.

  2. Monarch butterfly population decline in North America: identifying the threatening processes

    Science.gov (United States)

    Thogmartin, Wayne E.; Wiederholt, Ruscena; Oberhauser, Karen; Drum, Ryan G.; Diffendorfer, Jay E.; Altizer, Sonia; Taylor, Orley R.; Pleasants, John M.; Semmens, Darius J.; Semmens, Brice X.; Erickson, Richard A.; Libby, Kaitlin; Lopez-Hoffman, Laura

    2017-01-01

    The monarch butterfly (Danaus plexippus) population in North America has sharply declined over the last two decades. Despite rising concern over the monarch butterfly's status, no comprehensive study of the factors driving this decline has been conducted. Using partial least-squares regressions and time-series analysis, we investigated climatic and habitat-related factors influencing monarch population size from 1993 to 2014. Potential threats included climatic factors, habitat loss (milkweed and overwinter forest), disease and agricultural insecticide use (neonicotinoids). While climatic factors, principally breeding season temperature, were important determinants of annual variation in abundance, our results indicated strong negative relationships between population size and habitat loss variables, principally glyphosate use, but also weaker negative effects from the loss of overwinter forest and breeding season use of neonicotinoids. Further declines in population size because of glyphosate application are not expected. Thus, if remaining threats to habitat are mitigated we expect climate-induced stochastic variation of the eastern migratory population of monarch butterfly around a relatively stationary population size.

  3. Genetic Affiliation of Pre-Hispanic and Contemporary Mayas Through Maternal Linage.

    Science.gov (United States)

    Ochoa-Lugo, Mirna Isabel; Muñoz, María de Lourdes; Pérez-Ramírez, Gerardo; Beaty, Kristine G; López-Armenta, Mauro; Cervini-Silva, Javiera; Moreno-Galeana, Miguel; Meza, Adrián Martínez; Ramos, Eduardo; Crawford, Michael H; Romano-Pacheco, Arturo

    2016-04-01

    Maya civilization developed in Mesoamerica and encompassed the Yucatan Peninsula, Guatemala, Belize, part of the Mexican states of Tabasco and Chiapas, and the western parts of Honduras and El Salvador. This civilization persisted approximately 3,000 years and was one of the most advanced of its time, possessing the only known full writing system at the time, as well as art, sophisticated architecture, and mathematical and astronomical systems. This civilization reached the apex of its power and influence during the Preclassic period, from 2000 BCE to 250 CE. Genetic variation in the pre-Hispanic Mayas from archaeological sites in the Mexican states of Yucatan, Chiapas, Quintana Roo, and Tabasco and their relationship with the contemporary communities in these regions have not been previously studied. Consequently, the principal aim of this study was to determine mitochondrial DNA (mtDNA) variation in the pre-Hispanic Maya population and to assess the relationship of these individuals with contemporary Mesoamerican Maya and populations from Asia, Beringia, and North, Central, and South America. Our results revealed interactions and gene flow between populations in the different archaeological sites assessed in this study. The mtDNA haplogroup frequency in the pre-Hispanic Maya population (60.53%, 34.21%, and 5.26% for haplogroups A, C, and D, respectively) was similar to that of most Mexican and Guatemalan Maya populations, with haplogroup A exhibiting the highest frequency. Haplogroup B most likely arrived independently and mixed with populations carrying haplogroups A and C based on its absence in the pre-Hispanic Mexican Maya populations and low frequencies in most Mexican and Guatemalan Maya populations, although this also may be due to drift. Maya and Ciboneys sharing haplotype H10 belonged to haplogroup C1 and haplotype H4 of haplogroup D, suggesting shared regional haplotypes. This may indicate a shared genetic ancestry, suggesting more regional interaction

  4. Population decline in the Delta caribou herd with reference to other Alaskan herds

    Directory of Open Access Journals (Sweden)

    Patrick Valkenburg et al.

    1996-01-01

    Full Text Available After growing continuously for nearly 15 years, the Delta caribou herd began to decline in 1989. Most other Interior Alaskan herds also began declining. In the Delta herd, and in other herds, the declines were caused primarily by high summer mortality of calves and increased natural mortality of adult females. Other minor causes included increased winter mortality of calves, and reduced parturition rates of 3-year-old and older females. The decline in the Delta herd also coincided with increased wolf (Canis lupus numbers, winters with deeper than normal snow, and warm summers. Mean body weight of annual samples of 10-month-old female calves was consistently low during the decline. Except in some of the smallest Interior Alaskan herds, we conclude that evidence for population regulation in Alaskan caribou is weak, and that herds are likely to fluctuate within a wide range of densities due to complex interactions of predation and weather. Unless wolf numbers are influenced by man, the size of a caribou herd in a given year is likely to be largely a function of its size during the previous population low and the number of years of favorable weather in the interim.

  5. Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines.

    Science.gov (United States)

    Ceballos, Gerardo; Ehrlich, Paul R; Dirzo, Rodolfo

    2017-07-25

    The population extinction pulse we describe here shows, from a quantitative viewpoint, that Earth's sixth mass extinction is more severe than perceived when looking exclusively at species extinctions. Therefore, humanity needs to address anthropogenic population extirpation and decimation immediately. That conclusion is based on analyses of the numbers and degrees of range contraction (indicative of population shrinkage and/or population extinctions according to the International Union for Conservation of Nature) using a sample of 27,600 vertebrate species, and on a more detailed analysis documenting the population extinctions between 1900 and 2015 in 177 mammal species. We find that the rate of population loss in terrestrial vertebrates is extremely high-even in "species of low concern." In our sample, comprising nearly half of known vertebrate species, 32% (8,851/27,600) are decreasing; that is, they have decreased in population size and range. In the 177 mammals for which we have detailed data, all have lost 30% or more of their geographic ranges and more than 40% of the species have experienced severe population declines (>80% range shrinkage). Our data indicate that beyond global species extinctions Earth is experiencing a huge episode of population declines and extirpations, which will have negative cascading consequences on ecosystem functioning and services vital to sustaining civilization. We describe this as a "biological annihilation" to highlight the current magnitude of Earth's ongoing sixth major extinction event.

  6. Achieving population-level violence declines: implications of the international crime drop for prevention programming.

    Science.gov (United States)

    Eisner, Manuel; Nivette, Amy; Murray, Aja Louise; Krisch, Maria

    2016-09-01

    The Sustainable Development Goals (SDGs) adopted by the United Nations for the period 2016-2030 aim to achieve a substantial reduction of interpersonal violence. An increasing body of evidence of what works, emerging from randomized controlled trials, can inform public health policy decisions. However, there is very limited evidence on the kinds of mechanisms that lead to sustained declines in interpersonal violence at the population level. We discuss the implications of what is known about recent major declines in violence to guide violence-reduction policies.

  7. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline.

    Science.gov (United States)

    Bromaghin, Jeffrey F; Mcdonald, Trent L; Stirling, Ian; Derocher, Andrew E; Richardson, Evan S; Regehr, Eric V; Douglas, David C; Durner, George M; Atwood, Todd; Amstrup, Steven C

    2015-04-01

    In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species as threatened under the U.S. Endangered Species Act. Here, we used mark-recapture models to investigate the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010, years during which the spatial and temporal extent of summer sea ice generally declined. Low survival from 2004 through 2006 led to a 25-50% decline in abundance. We hypothesize that low survival during this period resulted from (1) unfavorable ice conditions that limited access to prey during multiple seasons; and possibly, (2) low prey abundance. For reasons that are not clear, survival of adults and cubs began to improve in 2007 and abundance was comparatively stable from 2008 to 2010, with ~900 bears in 2010 (90% CI 606-1212). However, survival of subadult bears declined throughout the entire period. Reduced spatial and temporal availability of sea ice is expected to increasingly force population dynamics of polar bears as the climate continues to warm. However, in the short term, our findings suggest that factors other than sea ice can influence survival. A refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary to improve projections of their future status and facilitate development of management strategies.

  8. Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline

    Science.gov (United States)

    Bromaghin, Jeffrey F.; McDonald, Trent L.; Stirling, Ian; Derocher, Andrew E.; Richardson, Evan S.; Regehr, Eric V.; Douglas, David C.; Durner, George M.; Atwood, Todd C.; Amstrup, Steven C.

    2015-01-01

    In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice habitat, those findings contributed to the 2008 decision to list the species as threatened under the U.S. Endangered Species Act. Here, we used mark–recapture models to investigate the population dynamics of polar bears in the southern Beaufort Sea from 2001 to 2010, years during which the spatial and temporal extent of summer sea ice generally declined. Low survival from 2004 through 2006 led to a 25–50% decline in abundance. We hypothesize that low survival during this period resulted from (1) unfavorable ice conditions that limited access to prey during multiple seasons; and possibly, (2) low prey abundance. For reasons that are not clear, survival of adults and cubs began to improve in 2007 and abundance was comparatively stable from 2008 to 2010, with ~900 bears in 2010 (90% CI 606–1212). However, survival of subadult bears declined throughout the entire period. Reduced spatial and temporal availability of sea ice is expected to increasingly force population dynamics of polar bears as the climate continues to warm. However, in the short term, our findings suggest that factors other than sea ice can influence survival. A refined understanding of the ecological mechanisms underlying polar bear population dynamics is necessary to improve projections of their future status and facilitate development of management strategies.

  9. Exposure of harbour seals Phoca vitulina to Brucella in declining populations across Scotland.

    Science.gov (United States)

    Kershaw, Joanna L; Stubberfield, Emma J; Foster, Geoffrey; Brownlow, Andrew; Hall, Ailsa J; Perrett, Lorraine L

    2017-09-20

    Since 2000 there has been a major decline in the abundance of Scottish harbour seals Phoca vitulina. The causes of the decline remain uncertain. The aim of this study was to establish the extent to which the seals in the regions of greatest decline have been exposed to Brucella, a bacterial pathogen that causes reproductive failure in terrestrial mammalian hosts. Tissues from dead seals collected between 1992 and 2013 were cultured for Brucella (n = 150). Serum samples collected from live capture-released seals (n = 343) between 1997 and 2012 were tested for Brucella antibodies using the Rose Bengal plate agglutination test (RBT) and a competitive enzyme-linked immunosorbent assay (cELISA). In total, 16% of seals cultured had Brucella isolated from one or more tissues, but there were no pathological signs of infection. The cELISA results were more sensitive than the RBT results, showing that overall 25.4% of seals were seropositive, with the highest seroprevalence in juveniles. As there was no evidence of either a higher seroprevalence or higher circulating antibody levels in seropositive animals in the areas with the greatest declines, it was concluded that Brucella infection is likely not a major contributing factor to recent declines. However, the consistently high proportion of seals exposed to Brucella indicates possible endemicity in these populations, likely due to B. pinnipedialis, which has demonstrated a preference for pinniped hosts. Importantly, given the close proximity between seals, humans and livestock in many areas, there is the potential for cross-species infections.

  10. Attributing mortality among drivers of population decline in Acropora palmata in the Florida Keys (USA)

    Science.gov (United States)

    Williams, D. E.; Miller, M. W.

    2012-06-01

    Acropora palmata populations have experienced steep declines over the past 30 years. Although numerous culprits are recognized, their relative contributions to the decline are poorly quantified, making it difficult to prioritize effective conservation measures. In 2004, a demographic monitoring program was implemented in the Florida Keys (USA), aimed at determining the relative importance of various stressors affecting A. palmata. A subset of randomly selected A. palmata colonies within 15 fore-reef plots was tagged and surveyed three to four times per year over 7 years. Colony size, live tissue, prevalence of disease, snail ( Coralliophila abbreviata) predation, physical damage and other conditions were assessed at each survey. The estimated effect of each condition causing recent mortality was ranked, and together, these parameters were used to attribute the population-level tissue loss associated with each condition. In addition, all new colonies in the study plots were counted and assessed annually in order to track trends in total colony count and live tissue abundance. Between 2004 and 2010, the study population has shown more than 50% decline in live area from three main conditions: fragmentation, disease and snail predation. Approximately half of this decline occurred during the catastrophic 2005 hurricane season from which recovery has been minimal. Meanwhile, colony abundance has shown gradual decline throughout the study. Snail predation was the most prevalent condition. However, it ranked third in attributed tissue loss, behind breakage that occurred during the 2005 hurricane season, and disease. Thermal bleaching of A. palmata was not observed during this study. Because mortality continues to outpace recruitment and growth, intervention to ameliorate losses to the more manageable threats including predation and breakage could result in substantial conservation of live tissue, buying time for the abatement of less tractable threats to A. palmata

  11. Declines revisited: Long-term recovery and spatial population dynamics oftailed frog larvae after wildfire

    Science.gov (United States)

    Hossack, Blake R.; Honeycutt, Richard

    2017-01-01

    Drought has fueled an increased frequency and severity of large wildfires in many ecosystems. Despite an increase in research on wildfire effects on vertebrates, the vast majority of it has focused on short-term (effects and there is still little information on the time scale of population recovery for species that decline in abundance after fire. In 2003, a large wildfire in Montana (USA) burned the watersheds of four of eight streams that we sampled for larval Rocky Mountain tailed frogs (Ascaphus montanus) in 2001. Surveys during 2004–2005 revealed reduced abundance of larvae in burned streams relative to unburned streams, with greater declines associated with increased fire extent. Rocky Mountain tailed frogs have low vagility and have several unusual life-history traits that could slow population recovery, including an extended larval period (4 years), delayed sexual maturity (6–8 years), and low fecundity (negative effects of burn extent on larval abundance weakened> 58% within 12 years after the fire. We also found moderate synchrony among populations in unburned streams and negative spatial autocorrelation among populations in burned streams. We suspect negative spatial autocorrelation among spatially-clustered burned streams reflected increased post-fire patchiness in resources and different rates of local recovery. Our results add to a growing body of work that suggests populations in intact ecosystems tend to be resilient to habitat changes caused by wildfire. Our results also provide important insights into recovery times of populations that have been negatively affected by severe wildfire.

  12. Study of the Maya concrete

    International Nuclear Information System (INIS)

    Diaz C, H.

    2000-01-01

    The materials with which were constructed the buildings of the archaeological zone at the Maya culture were studied. Studies about the chemical composition of cement samples used in the construction of the Maya buildings were realized. The cement used was the same in all archaeological zones studied. The cement constituted the cementing matrix to obtain its derivatives: stuccos, mortars and, concretes. It was found that the Maya cement although has a variable chemical composition in its constitutive elements percentages, it is composed basically of calcite with fortuitous combinations of dolomite and clay materials, this last was founded in variable quantities from 0 % up to 10 % weight. The Maya cement was characterized as a variety of natural cement. The analysis and elemental chemical characterization was realized through the Scanning Electron Microscopy, X-ray diffraction and spectroscopic techniques. Therefore the microstructural characterization and the elemental chemical analysis were realized with a Scanning Electron microscope Phillips model XL30. The X-ray diffraction analysis was realized with a dust diffractometer Siemens D5000 operating at 30 KeV. The study of spectrograph was realized with an Emission spectrograph at 3 m focal distance model GX-1 Baird Atomic. (Author)

  13. Endemic chronic wasting disease causes mule deer population decline in Wyoming

    Science.gov (United States)

    DeVivo, Melia T.; Edmunds, David R.; Kauffman, Matthew J.; Schumaker, Brant A.; Binfet, Justin; Kreeger, Terry J.; Richards, Bryan J.; Schatzl, Hermann M.; Cornish, Todd

    2017-01-01

    Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy affecting white-tailed deer (Odocoileus virginianus), mule deer (Odocoileus hemionus), Rocky Mountain elk (Cervus elaphus nelsoni), and moose (Alces alces shirasi) in North America. In southeastern Wyoming average annual CWD prevalence in mule deer exceeds 20% and appears to contribute to regional population declines. We determined the effect of CWD on mule deer demography using age-specific, female-only, CWD transition matrix models to estimate the population growth rate (λ). Mule deer were captured from 2010–2014 in southern Converse County Wyoming, USA. Captured adult (≥ 1.5 years old) deer were tested ante-mortem for CWD using tonsil biopsies and monitored using radio telemetry. Mean annual survival rates of CWD-negative and CWD-positive deer were 0.76 and 0.32, respectively. Pregnancy and fawn recruitment were not observed to be influenced by CWD. We estimated λ= 0.79, indicating an annual population decline of 21% under current CWD prevalence levels. A model derived from the demography of only CWD-negative individuals yielded; λ = 1.00, indicating a stable population if CWD were absent. These findings support CWD as a significant contributor to mule deer population decline. Chronic wasting disease is difficult or impossible to eradicate with current tools, given significant environmental contamination, and at present our best recommendation for control of this disease is to minimize spread to new areas and naïve cervid populations.

  14. Hungarian Population Discourses in the Twentieth Century: The Problem of Declining Birth Rates

    OpenAIRE

    Ildikó Szántó

    2016-01-01

    Falling birth rates had already been recorded as early as the late-eighteenth century in south-western Hungary in the Ormánság. Population loss from low birth rate remained one of the main topics writers and sociologists focused on in the twentieth century. The issue of Hungarian population decline was highlighted among the social ills in the interwar period, which was one of several subjects that divided intellectuals into ‘populists’ and ‘urbanites’. Following the impact of the low birth ra...

  15. Integrated analysis for population estimation, management impact evaluation, and decision-making for a declining species

    Science.gov (United States)

    Crawford, Brian A.; Moore, Clinton; Norton, Terry M.; Maerz, John C.

    2018-01-01

    A challenge for making conservation decisions is predicting how wildlife populations respond to multiple, concurrent threats and potential management strategies, usually under substantial uncertainty. Integrated modeling approaches can improve estimation of demographic rates necessary for making predictions, even for rare or cryptic species with sparse data, but their use in management applications is limited. We developed integrated models for a population of diamondback terrapins (Malaclemys terrapin) impacted by road-associated threats to (i) jointly estimate demographic rates from two mark-recapture datasets, while directly estimating road mortality and the impact of management actions deployed during the study; and (ii) project the population using population viability analysis under simulated management strategies to inform decision-making. Without management, population extirpation was nearly certain due to demographic impacts of road mortality, predators, and vegetation. Installation of novel flashing signage increased survival of terrapins that crossed roads by 30%. Signage, along with small roadside barriers installed during the study, increased population persistence probability, but the population was still predicted to decline. Management strategies that included actions targeting multiple threats and demographic rates resulted in the highest persistence probability, and roadside barriers, which increased adult survival, were predicted to increase persistence more than other actions. Our results support earlier findings showing mitigation of multiple threats is likely required to increase the viability of declining populations. Our approach illustrates how integrated models may be adapted to use limited data efficiently, represent system complexity, evaluate impacts of threats and management actions, and provide decision-relevant information for conservation of at-risk populations.

  16. Inter-annual variability and long-term trends in breeding success in a declining population of migratory swans.

    NARCIS (Netherlands)

    Wood, K.A.; Newth, J.L.; Hilton, G.M.; Nolet, B.A.; Rees, E.C.

    2016-01-01

    Population declines among migratory Arctic-breeding birds are a growing concern for conservationists. To inform the conservation of these declining populations, we need to understand how demographic rates such as breeding success are influenced by combinations of extrinsic and intrinsic factors. In

  17. Demographic models and IPCC climate projections predict the decline of an emperor penguin population

    Science.gov (United States)

    Jenouvrier, Stéphanie; Caswell, Hal; Barbraud, Christophe; Holland, Marika; Strœve, Julienne; Weimerskirch, Henri

    2009-01-01

    Studies have reported important effects of recent climate change on Antarctic species, but there has been to our knowledge no attempt to explicitly link those results to forecasted population responses to climate change. Antarctic sea ice extent (SIE) is projected to shrink as concentrations of atmospheric greenhouse gases (GHGs) increase, and emperor penguins (Aptenodytes forsteri) are extremely sensitive to these changes because they use sea ice as a breeding, foraging and molting habitat. We project emperor penguin population responses to future sea ice changes, using a stochastic population model that combines a unique long-term demographic dataset (1962–2005) from a colony in Terre Adélie, Antarctica and projections of SIE from General Circulation Models (GCM) of Earth's climate included in the most recent Intergovernmental Panel on Climate Change (IPCC) assessment report. We show that the increased frequency of warm events associated with projected decreases in SIE will reduce the population viability. The probability of quasi-extinction (a decline of 95% or more) is at least 36% by 2100. The median population size is projected to decline from ≈6,000 to ≈400 breeding pairs over this period. To avoid extinction, emperor penguins will have to adapt, migrate or change the timing of their growth stages. However, given the future projected increases in GHGs and its effect on Antarctic climate, evolution or migration seem unlikely for such long lived species at the remote southern end of the Earth. PMID:19171908

  18. Global climate change, war, and population decline in recent human history.

    Science.gov (United States)

    Zhang, David D; Brecke, Peter; Lee, Harry F; He, Yuan-Qing; Zhang, Jane

    2007-12-04

    Although scientists have warned of possible social perils resulting from climate change, the impacts of long-term climate change on social unrest and population collapse have not been quantitatively investigated. In this study, high-resolution paleo-climatic data have been used to explore at a macroscale the effects of climate change on the outbreak of war and population decline in the preindustrial era. We show that long-term fluctuations of war frequency and population changes followed the cycles of temperature change. Further analyses show that cooling impeded agricultural production, which brought about a series of serious social problems, including price inflation, then successively war outbreak, famine, and population decline successively. The findings suggest that worldwide and synchronistic war-peace, population, and price cycles in recent centuries have been driven mainly by long-term climate change. The findings also imply that social mechanisms that might mitigate the impact of climate change were not significantly effective during the study period. Climate change may thus have played a more important role and imposed a wider ranging effect on human civilization than has so far been suggested. Findings of this research may lend an additional dimension to the classic concepts of Malthusianism and Darwinism.

  19. Population and colony-level determinants of tertiary sex ratio in the declining barn swallow.

    Directory of Open Access Journals (Sweden)

    Nicola Saino

    Full Text Available Sex ratio of adults (tertiary sex ratio, TSR is a major feature of animal populations with consequences for their behaviour, genetic structure and viability. Spatial and temporal variation in TSR occurs within species but the mechanisms behind it are poorly understood. In this long-term study of a declining population of a socially monogamous, colonial, migratory bird, the barn swallow (Hirundo rustica, we first analyzed population-level variation in TSR ( =  proportion of males of yearlings at sexual maturation in relation to ecological conditions as gauged by annual survival rate of adults. TSR was male-biased both among yearlings and older individuals, but male bias of yearlings was more pronounced after years with larger decline in adult survival. Thus, male offspring were less susceptible to the adverse ecological conditions that cause increased mortality. Dispersal and settling site decisions can have major consequences on fitness via the effects of local TSR on mating and sperm competition. Breeding barn swallows are highly philopatric while natal dispersal is high and, together with mortality, is the main determinant of colony TSR. We thus also investigated the mechanisms of breeding colony choice by yearlings and found that TSR of new-settlers in a given colony and year was negatively predicted by TSR of returning, early arriving older individuals in that year, but not by overall TSR at the colony in the previous year. This suggests that in our male-biased population new-settler males respond to local TSR upon arrival to choose the sites with larger breeding opportunities. Hence, variation in ecological conditions as reflected by adult survival can shift the TSR of individuals recruiting into a local population, with potentially various demographic consequences. However, breeding site choice based on TSR tends to homogenize TSR at a population level likely by facilitating settling of dispersing males in colonies with less male

  20. Competing discourses of the “Maya Past”

    Directory of Open Access Journals (Sweden)

    Denise Fay Brown

    2010-12-01

    Full Text Available The use of the "Maya past" for tourism marketing purposes has been a successful tool for attracting international visitors to Mexico for decades. Images of the Maya zone emerge, in part, from an academic focus on the "Maya past" that includes curiosity about the so-called "collapse" of the Classic Maya civilization. The Ancient Maya are seen as “mysterious" and their society as "enigmatic". But the voices of the almost thirty million Maya people who live in Mexico and Guatemala are only vaguely heard in the discourses of tourism and of academia. This paper examines three competing discourses of the Maya and proposes that these discourses represent epistemologies that are nested in relationships of power, such that the Maya discourse is silenced. As such, the dominant discourses of the Maya past can undermine the Maya understanding of their own past, and become a self-fulfilling prophecy regarding the “collapse” of the contemporary Maya.

  1. Spatial behaviour of little owls (Athene noctua) in a declining low-density population in Denmark

    DEFF Research Database (Denmark)

    Sunde, Peter; Thorup, Kasper; Jacobsen, Lars Bo

    2009-01-01

    Knowledge of a species' spatial behaviour is essential for understanding its behavioural ecology and a prerequisite to planning of conservation strategies. The little owl has shown a substantial decline in North-western Europe and is on the road of extinction in Denmark. To quantify relevant...... aspects of spatial behaviour in the last remaining Danish population, we followed 27 radio-tagged owls representing 14 territories during a period of 2 years. Mated owls were resident at nesting sites year-round with half of all nocturnal locations found within 125 m. Nightly distance from roosts peaked...

  2. Freeing Maya Angelou's Caged Bird

    OpenAIRE

    Graham, Joyce L.

    1991-01-01

    This study involves a comprehensive examination of one book, Maya Angelou's autobiographical I Know Why Why the Caged Bird Sings, since it was first published in 1970. Recognized as an important literary work, the novel is used in many middle and secondary school classrooms throughout the united States. Additionally, the work often is challenged in public schools on the grounds of its sexual and/or racial content. The purpose of this study included establishing th...

  3. Using latent selection difference to model persistence in a declining population.

    Directory of Open Access Journals (Sweden)

    Mara E Erickson

    Full Text Available Population persistence is a direct measure of the viability of a population. Monitoring the distribution of declining populations or subpopulations over time can yield estimates of persistence, which we show can be modeled as a latent selection difference (LSD contrasting attributes of sites where populations have persisted versus those that have not. Predicted persistence can be modeled with predictor covariates to identify factors correlated with species persistence. We demonstrate how to model persistence based on changes in occupancy that can include adjustments for detection probability. Using a known historical distribution of the western grebe (Aechmophorus occidentalis, we adapted methods originally developed for occupancy modeling to evaluate how environmental covariates including emergent vegetation and human developments have affected western grebe persistence in Alberta. The relative probability of persistence was correlated with the extent of shoreline bulrush (Scirpus lacustris, which is important vegetation for nesting cover. We also documented that western grebe populations were less likely to persist on lakes in the boreal forest, primarily located on the northern boundary of the species' range. Factors influencing occupancy were different than those determining persistence by western grebes; persistence and occupancy were not correlated. Persistence was more likely on lakes with recreational development, reflecting reliance by grebes on the larger, fish-bearing waterbodies that also are attractive for lakeshore development. Unfortunately, the correlation with recreational development on Alberta's lakes puts grebes at risk for loss of brood-rearing habitats--primary threats to altricial birds--if steps are not taken to prevent disturbance to bulrush stands. Identifying factors related to the persistence of a species--especially one in decline--is a fundamental step in conservation management.

  4. Chronic wasting disease drives population decline of white-tailed deer

    Science.gov (United States)

    Edmunds, David; Kauffman, Matthew J.; Schumaker, Brant; Lindzey, Frederick G.; Cook, Walter; Kreeger, Terry J.; Grogan, Ronald; Cornish, Todd

    2016-01-01

    Chronic wasting disease (CWD) is an invariably fatal transmissible spongiform encephalopathy of white-tailed deer, mule deer, elk, and moose. Despite a 100% fatality rate, areas of high prevalence, and increasingly expanding geographic endemic areas, little is known about the population-level effects of CWD in deer. To investigate these effects, we tested the null hypothesis that high prevalence CWD did not negatively impact white-tailed deer population sustainability. The specific objectives of the study were to monitor CWD-positive and CWD-negative white-tailed deer in a high-prevalence CWD area longitudinally via radio-telemetry and global positioning system (GPS) collars. For the two populations, we determined the following: a) demographic and disease indices, b) annual survival, and c) finite rate of population growth (λ). The CWD prevalence was higher in females (42%) than males (28.8%) and hunter harvest and clinical CWD were the most frequent causes of mortality, with CWD-positive deer over-represented in harvest and total mortalities. Survival was significantly lower for CWD-positive deer and separately by sex; CWD-positive deer were 4.5 times more likely to die annually than CWD-negative deer while bucks were 1.7 times more likely to die than does. Population λ was 0.896 (0.859–0.980), which indicated a 10.4% annual decline. We show that a chronic disease that becomes endemic in wildlife populations has the potential to be population-limiting and the strong population-level effects of CWD suggest affected populations are not sustainable at high disease prevalence under current harvest levels.

  5. Agriculture modifies the seasonal decline of breeding success in a tropical wild bird population

    Science.gov (United States)

    Cartwright, Samantha J; Nicoll, Malcolm A C; Jones, Carl G; Tatayah, Vikash; Norris, Ken

    2014-01-01

    Habitat conversion for agriculture is a major driver of biodiversity loss, but our understanding of the demographic processes involved remains poor. We typically investigate the impacts of agriculture in isolation even though populations are likely to experience multiple, concurrent changes in the environment (e.g. land and climate change). Drivers of environmental change may interact to affect demography, but the mechanisms have yet to be explored fully in wild populations. Here, we investigate the mechanisms linking agricultural land use with breeding success using long-term data for the formerly Critically Endangered Mauritius kestrel Falco punctatus, a tropical forest specialist that also occupies agricultural habitats. We specifically focused on the relationship between breeding success, agriculture and the timing of breeding because the latter is sensitive to changes in climatic conditions (spring rainfall) and enables us to explore the interactive effects of different (land and climate) drivers of environmental change. Breeding success, measured as egg survival to fledging, declines seasonally in this population, but we found that the rate of this decline became increasingly rapid as the area of agriculture around a nest site increased. If the relationship between breeding success and agriculture was used in isolation to estimate the demographic impact of agriculture, it would significantly under-estimate breeding success in dry (early) springs and over-estimate breeding success in wet (late) springs. Analysis of prey delivered to nests suggests that the relationship between breeding success and agriculture might be due, in part, to spatial variation in the availability of native, arboreal geckos. Synthesis and applications. Agriculture modifies the seasonal decline in breeding success in this population. As springs are becoming wetter in our study area and since the kestrels breed later in wetter springs, the impact of agriculture on breeding success will

  6. Assay dependence of Brucella antibody prevalence in a declining Alaskan harbor seal (Phoca vitulina population

    Directory of Open Access Journals (Sweden)

    Hueffer Karsten

    2013-01-01

    Full Text Available Abstract Background Brucella is a group of bacteria that causes brucellosis, which can affect population health and reproductive success in many marine mammals. We investigated the serological prevalence of antibodies against Brucella bacteria in a declining harbor seal population in Glacier Bay National Park, Alaska. Results Prevalence ranged from 16 to 74 percent for those tests detecting antibodies, indicating that harbor seals in Glacier Bay have been exposed to Brucella bacteria. However, the actual level of serological prevalence could not be determined because results were strongly assay-dependent. Conclusions This study reinforces the need to carefully consider assay choice when comparing different studies on the prevalence of anti–Brucella antibodies in pinnipeds and further highlights the need for species- or taxon-specific assay validation for both pathogen and host species.

  7. Breeding season food limitation drives population decline of the Little Owl Athene noctua in Denmark

    DEFF Research Database (Denmark)

    Thorup, Kasper; Sunde, Peter; Jacobsen, Lars B.

    2010-01-01

    landscape, has declined over most of northwestern Europe, including Denmark. We investigated the likely reasons for the population decline in Denmark by identifying patterns of local extinction (scale, 5 x 5 km2) and estimating demographic parameters affecting local survival, focusing on changes over time...

  8. Garter snakes distributions in high elevation aquatic ecosystems: Is there a link with declining amphibian populations and nonnative trout introductions?

    Science.gov (United States)

    K.R. Matthews; R.A. Knapp; K.L. Pope

    2002-01-01

    ABSTRACT.—The dramatic amphibian population declines reported worldwide likely have important effects on their predators. In the Sierra Nevada, where amphibian declines are well documented and some are closely tied to the introduction of nonnative trout, the mountain garter snake, Thamnophis elegans elegans, preys predominately on amphibians. We surveyed 2103 high-...

  9. Thyroid Antibodies, Autoimmunity and Cognitive Decline: Is There a Population-Based Link

    Directory of Open Access Journals (Sweden)

    Kate Napthali

    2014-05-01

    Full Text Available Background: Autoimmunity is considered an uncommon but under-recognised cause of cognitive decline. Methods: Serum samples from 3,253 randomly selected subjects enrolled in the Hunter Community Study, aged 55-85 years, were assayed for thyrotropin stimulatory hormone, anti-thyroid peroxidase antibodies (TPO-Ab, anti-nuclear antibodies (ANA and extractable nuclear antigens (ENA. Cognitive function was assessed using the Audio Recorded Cognitive Screen (ARCS tool. Results: TPO-Ab were found in 8.4% and ANA in 27.9% of the study population, of whom 3% had positive ENA findings. No relationship was found between the ARCS score and either TPO-Ab (coefficient = 0.133; 95% CI -0.20, 0.82, p = 0.616, ANA at a low (coefficient = 1.01; 95% CI -2.58, 0.55, p = 0.203 or a high titre (coefficient = -0.65; 95% CI -2.59, 1.28, p = 0.508, or ENA antibodies (coefficient = 5.12; 95% CI -0.53, 10.77; p = 0.076. Conclusions: Autoantibody findings are common in an aging population and are not associated with cognitive decline.

  10. Modeling routes of chronic wasting disease transmission: Environmental prion persistence promotes deer population decline and extinction

    Science.gov (United States)

    Almberg, Emily S.; Cross, Paul C.; Johnson, Christopher J.; Heisey, Dennis M.; Richards, Bryan J.

    2011-01-01

    Chronic wasting disease (CWD) is a fatal disease of deer, elk, and moose transmitted through direct, animal-to-animal contact, and indirectly, via environmental contamination. Considerable attention has been paid to modeling direct transmission, but despite the fact that CWD prions can remain infectious in the environment for years, relatively little information exists about the potential effects of indirect transmission on CWD dynamics. In the present study, we use simulation models to demonstrate how indirect transmission and the duration of environmental prion persistence may affect epidemics of CWD and populations of North American deer. Existing data from Colorado, Wyoming, and Wisconsin's CWD epidemics were used to define plausible short-term outcomes and associated parameter spaces. Resulting long-term outcomes range from relatively low disease prevalence and limited host-population decline to host-population collapse and extinction. Our models suggest that disease prevalence and the severity of population decline is driven by the duration that prions remain infectious in the environment. Despite relatively low epidemic growth rates, the basic reproductive number, R0, may be much larger than expected under the direct-transmission paradigm because the infectious period can vastly exceed the host's life span. High prion persistence is expected to lead to an increasing environmental pool of prions during the early phases (i.e. approximately during the first 50 years) of the epidemic. As a consequence, over this period of time, disease dynamics will become more heavily influenced by indirect transmission, which may explain some of the observed regional differences in age and sex-specific disease patterns. This suggests management interventions, such as culling or vaccination, will become increasingly less effective as CWD epidemics progress.

  11. Directional layouts in central lowland Maya settlement

    DEFF Research Database (Denmark)

    Bevan, Andrew; Jobbová, Eva; Helmke, Christophe

    2013-01-01

    This paper suggests the existence of non-random, directional patterns in the location of housemounds across the Late Classic Maya settlement landscape at Baking Pot, Belize, and then explores the wider implications of this patterning in the central Maya lowlands. It introduces an anisotropic method...

  12. Activity patterns and time budgets of the declining sea otter population at Amchitka Island, Alaska

    Science.gov (United States)

    Gelatt, Thomas S.; Siniff, Donald B.; Estes, James A.

    2002-01-01

    Time budgets of predators may reflect population status if time spent foraging varies with local prey abun- dance. We assumed that the sea otter (Enhydra lutris) population at Amchitka Island, Alaska, USA, had been at equilibrium since the early 1960s and collected time budgets of otters to be used to represent future conditions of currently expanding sea otter populations. We used radiotelemetry to monitor activity-time budgets of otters from August 1992 to March 1994. Sea otter activity was directly linked to sex, age, weather condition, season, and time of day. Sea otters differed in percent time foraging among cohorts but not within cohorts. Percent time foraging ranged from 21% for females with very young (≤ 3weeks of age) dependent pups to 52% for females with old (≥10 weeks of age) pups. Otters foraged more and hauled out more as local sea conditions worsened. Adult males spent less time foraging during winter and spring, consistent with seasonal changes in prey selection. Time spent for- aging was similar to that reported for otters in California and an established population in Prince William Sound, Alaska, but greater than that of otters in recently established populations in Oregon and Alaska. Despite current evidence indicating that the population was in decline during our study, we were unable to recognize this change using time budgets. Our results illustrate the importance of stratifying analyses of activity patterns by age and sex cohorts and the complexity inherent in comparisons of behavioral data between different populations relying on distinct prey bases.

  13. When is a species declining? Optimizing survey effort to detect population changes in reptiles.

    Directory of Open Access Journals (Sweden)

    David Sewell

    Full Text Available Biodiversity monitoring programs need to be designed so that population changes can be detected reliably. This can be problematical for species that are cryptic and have imperfect detection. We used occupancy modeling and power analysis to optimize the survey design for reptile monitoring programs in the UK. Surveys were carried out six times a year in 2009-2010 at multiple sites. Four out of the six species--grass snake, adder, common lizard, slow-worm -were encountered during every survey from March-September. The exceptions were the two rarest species--sand lizard and smooth snake--which were not encountered in July 2009 and March 2010 respectively. The most frequently encountered and most easily detected species was the slow-worm. For the four widespread reptile species in the UK, three to four survey visits that used a combination of directed transect walks and artificial cover objects resulted in 95% certainty that a species would be detected if present. Using artificial cover objects was an effective detection method for most species, considerably increased the detection rate of some, and reduced misidentifications. To achieve an 85% power to detect a decline in any of the four widespread species when the true decline is 15%, three surveys at a total of 886 sampling sites, or four surveys at a total of 688 sites would be required. The sampling effort needed reduces to 212 sites surveyed three times, or 167 sites surveyed four times, if the target is to detect a true decline of 30% with the same power. The results obtained can be used to refine reptile survey protocols in the UK and elsewhere. On a wider scale, the occupancy study design approach can be used to optimize survey effort and help set targets for conservation outcomes for regional or national biodiversity assessments.

  14. Can individual and social patterns of resource use buffer animal populations against resource decline?

    Directory of Open Access Journals (Sweden)

    Sam C Banks

    Full Text Available Species in many ecosystems are facing declines of key resources. If we are to understand and predict the effects of resource loss on natural populations, we need to understand whether and how the way animals use resources changes under resource decline. We investigated how the abundance of arboreal marsupials varies in response to a critical resource, hollow-bearing trees. Principally, we asked what mechanisms mediate the relationship between resources and abundance? Do animals use a greater or smaller proportion of the remaining resource, and is there a change in cooperative resource use (den sharing, as the availability of hollow trees declines? Analyses of data from 160 sites surveyed from 1997 to 2007 showed that hollow tree availability was positively associated with abundance of the mountain brushtail possum, the agile antechinus and the greater glider. The abundance of Leadbeater's possum was primarily influenced by forest age. Notably, the relationship between abundance and hollow tree availability was significantly less than 1:1 for all species. This was due primarily to a significant increase by all species in the proportional use of hollow-bearing trees where the abundance of this resource was low. The resource-sharing response was weaker and inconsistent among species. Two species, the mountain brushtail possum and the agile antechinus, showed significant but contrasting relationships between the number of animals per occupied tree and hollow tree abundance. The discrepancies between the species can be explained partly by differences in several aspects of the species' biology, including body size, types of hollows used and social behaviour as it relates to hollow use. Our results show that individual and social aspects of resource use are not always static in response to resource availability and support the need to account for dynamic resource use patterns in predictive models of animal distribution and abundance.

  15. Decline in admissions for childhood asthma, a 26-year period population-based study.

    Science.gov (United States)

    Mikalsen, Ingvild Bruun; Skeiseid, Liliane; Tveit, Line Merete; Engelsvold, David Hugo; Øymar, Knut

    2015-12-01

    The prevalence of childhood asthma has increased, although the rate of hospitalization for asthma seems to decrease. In Norway, the rate of hospital admission for childhood asthma from 1984 to 2000 increased. The aim of this study was to assess further trends in hospital admissions for childhood asthma up to 2010. A population-based study including children 1-13 yrs of age hospitalized for asthma during six periods from 1984/1985 to 2009/2010 in Rogaland, Norway, was performed. Medical records from 1536 admissions (1050 children) were studied; and gender, age, number of admissions, length of hospital stay, medications and symptoms were recorded. For all age groups, the rate of admissions per 10.000 increased from 20.1 in 1984/85 to 33.7 in 1989/90, but declined to 14.4 in 2009/2010. Rates were highest in boys (OR 1.87; 95% CI: 1.69, 2.09), younger age groups (OR 2.51; 2.38, 2.64) and decreased from 1984 to 2010 (OR 0.92; 0.88, 0.94). The rates of readmissions were higher than for primary admissions (OR 1.33; 1.19, 1.47). From 1984 to 2010, there was an increased use of inhaled corticosteroids prior to admission (6 to 51%) and started at discharge (7 to 37%), and systemic steroids given during admission (19 to 83%). There has been a substantial decline in the rate of hospital admissions for childhood asthma after 1989/1990, with major differences between age groups and genders. The decline could be due to improved care of children with asthma or a real reduction in asthma exacerbations. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Cumulative Trauma Among Mayas Living in Southeast Florida.

    Science.gov (United States)

    Millender, Eugenia I; Lowe, John

    2017-06-01

    Mayas, having experienced genocide, exile, and severe poverty, are at high risk for the consequences of cumulative trauma that continually resurfaces through current fear of an uncertain future. Little is known about the mental health and alcohol use status of this population. This correlational study explored t/he relationship of cumulative trauma as it relates to social determinants of health (years in the United States, education, health insurance status, marital status, and employment), psychological health (depression symptoms), and health behaviors (alcohol use) of 102 Guatemalan Mayas living in Southeast Florida. The results of this study indicated that, as specific social determinants of health and cumulative trauma increased, depression symptoms (particularly among women) and the risk for harmful alcohol use (particularly among men) increased. Identifying risk factors at an early stage before serious disease or problems are manifest provides room for early screening leading to early identification, early treatment, and better outcomes.

  17. Ecophysiology meets conservation: understanding the role of disease in amphibian population declines

    Science.gov (United States)

    Blaustein, Andrew R.; Gervasi, Stephanie S.; Johnson, Pieter T. J.; Hoverman, Jason T.; Belden, Lisa K.; Bradley, Paul W.; Xie, Gisselle Y.

    2012-01-01

    Infectious diseases are intimately associated with the dynamics of biodiversity. However, the role that infectious disease plays within ecological communities is complex. The complex effects of infectious disease at the scale of communities and ecosystems are driven by the interaction between host and pathogen. Whether or not a given host–pathogen interaction results in progression from infection to disease is largely dependent on the physiological characteristics of the host within the context of the external environment. Here, we highlight the importance of understanding the outcome of infection and disease in the context of host ecophysiology using amphibians as a model system. Amphibians are ideal for such a discussion because many of their populations are experiencing declines and extinctions, with disease as an important factor implicated in many declines and extinctions. Exposure to pathogens and the host's responses to infection can be influenced by many factors related to physiology such as host life history, immunology, endocrinology, resource acquisition, behaviour and changing climates. In our review, we discuss the relationship between disease and biodiversity. We highlight the dynamics of three amphibian host–pathogen systems that induce different effects on hosts and life stages and illustrate the complexity of amphibian–host–parasite systems. We then review links between environmental stress, endocrine–immune interactions, disease and climate change. PMID:22566676

  18. Hungarian Population Discourses in the Twentieth Century: The Problem of Declining Birth Rates

    Directory of Open Access Journals (Sweden)

    Ildikó Szántó

    2016-01-01

    Full Text Available Falling birth rates had already been recorded as early as the late-eighteenth century in south-western Hungary in the Ormánság. Population loss from low birth rate remained one of the main topics writers and sociologists focused on in the twentieth century. The issue of Hungarian population decline was highlighted among the social ills in the interwar period, which was one of several subjects that divided intellectuals into ‘populists’ and ‘urbanites’. Following the impact of the low birth rate figures in the 1960s, the populists’ views of the 1930s resurfaced in public discourse in the 1960s and 1970s and up to the present day. The concern about the increasing trend of single-child families in rural settlements as well as in urban areas appeared in the various works of Hungarian writers and journalists throughout the previous century. The present paper intends to focus on the intellectual background to the public debates on the population issue, outlining the accounts of the interwar ‘village explorers’ briefly, and the way they are related to the pre-Second World War populist movement. Finally the reappearance of the debates between populists and non-populists of the 1970s is discussed, a debate that is still continuing.

  19. Could Immigration Prevent Population Decline? The Demographic Prospects of Germany Revisited

    Directory of Open Access Journals (Sweden)

    Hannes Weber

    2015-04-01

    Full Text Available Germany has a record of more than 40 years of below-replacement fertility and annual death surplus. Hence, it is commonly accepted that Germany’s population will decline considerably in the coming decades. Recent increases in immigration may, however, challenge the official long-term demographic projections for Germany. This paper assesses the impact of a permanent higher-than-expected level of net immigration to Germany as in the past three years on the projections for population, age structure and ethnic makeup by mid-century.The paper adds a higher immigration variant to the Federal Statistical Office’s latest Coordinated Population Projection and two variants of a (a constant or (b decreasing fertility rate among migrant women. It can be shown that with permanent net migration as high as in recent years (around 300,000 per annum, Germany’s population would not significantly decrease in the coming decades but would rather remain at 80 million until 2050. On the other hand, the sharp rise in the old-age dependency ratio is only mildly weakened by increased immigration rates. This issue is therefore probably best addressed by other (or additional means. The increase in retirees will level off after 2035 in any case. The ethnic makeup of society would be affected to a greater degree than its age composition: The share of first- and second-generation immigrants among the total population is projected to rise to about 35 percent in this scenario (and to above 40 percent if the third generation is also counted.

  20. Some economic consequences of an ageing and declining population in Denmark.

    Science.gov (United States)

    Leeson, G W

    1983-01-01

    Figures for 1981 indicate that Denmark has a fertility level of 1.45 which has been below replacement level since 1968. In that same time period, natural increase has decreased from over 27,000 in 1968 to only 1354 in 1980 and a negative natural increase in 1981 with deaths outnumbering births by 3001. Even during the depression in the 1930's, net population increase was between 6-9/1000 with a fertility level which hovered around replacement level. At that time, the number of females in the childbearing ages was enough to provide population growth, whereas the number is much less today. Population increase is only 0.3/1000. The national population projections for Denmark for 1981-2010 assume an increase in the fertility level from 1.45-1.70 by 1991 after which it remains constant. The number of 20-39 year olds increased steadily until 1945 after which there was a decline as the cohorts from periods with low fertility levels entered this age group, but this was again followed by a steady increase to the present day. The number of females aged 0-39 years is expected to decrease in all age groups to the year 2000. Those aged 40-59 increased in numbers from 1920 to the mid 1960s, since then they have decreased in number, but an increase is forcast for the remainder of the century. The number of elderly females also increased steadily from 1930-80, from about 200,000 to over 550,000; this is expected to continue until 1990 when a short-term decline will set in. Regarding the economic and social consequences of these trends, it is shown that the present decline in fertility has its origins in a period of low unemployment and its negative growth while there was still relatively low unemployment and economic growth. In 1973 the unemployed rate was 0.9% of the work force and this rose to 9.2% in 1981. The Danish population has aged from one with 1/4 million people aged 60 and over at the turn of the century to about 1 million of that age today. Also, the aged themselves

  1. EU protected area network did not prevent a country wide population decline in a threatened grassland bird

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    João P. Silva

    2018-01-01

    Full Text Available Background Few studies have assessed the effectiveness of the Protected Area networks on the conservation status of target species. Here, we assess the effectiveness of the Portuguese Natura 2000 (the European Union network of protected areas in maintaining a species included in the Annex I of the Bird Directive, namely the population of a priority farmland bird, the little bustard Tetrax tetrax. Methods We measured the effectiveness of the Natura 2000 by comparing population trends across time (2003–2006 and 2016 in 51 areas, 21 of which within 12 Special Protection Areas (SPA that were mostly designated for farmland bird conservation and another 30 areas without EU protection. Results Overall, the national population is estimated to have declined 49% over the last 10–14 years. This loss was found to be proportionally larger outside SPA (64% decline compared to losses within SPA (25% decline. However, the absolute male density decline was significantly larger within SPA . Discussion In spite of holding higher population densities and having prevented habitat loss, we conclude that Natura 2000 was not effective in buffering against the overall bustard population decline. Results show that the mere designation of SPA in farmland is not enough to secure species populations and has to be combined with agricultural policies and investment to maintain not only habitat availability but also habitat quality.

  2. EU protected area network did not prevent a country wide population decline in a threatened grassland bird.

    Science.gov (United States)

    Silva, João P; Correia, Ricardo; Alonso, Hany; Martins, Ricardo C; D'Amico, Marcello; Delgado, Ana; Sampaio, Hugo; Godinho, Carlos; Moreira, Francisco

    2018-01-01

    Few studies have assessed the effectiveness of the Protected Area networks on the conservation status of target species. Here, we assess the effectiveness of the Portuguese Natura 2000 (the European Union network of protected areas) in maintaining a species included in the Annex I of the Bird Directive, namely the population of a priority farmland bird, the little bustard Tetrax tetrax . We measured the effectiveness of the Natura 2000 by comparing population trends across time (2003-2006 and 2016) in 51 areas, 21 of which within 12 Special Protection Areas (SPA) that were mostly designated for farmland bird conservation and another 30 areas without EU protection. Overall, the national population is estimated to have declined 49% over the last 10-14 years. This loss was found to be proportionally larger outside SPA (64% decline) compared to losses within SPA (25% decline). However, the absolute male density decline was significantly larger within SPA . In spite of holding higher population densities and having prevented habitat loss, we conclude that Natura 2000 was not effective in buffering against the overall bustard population decline. Results show that the mere designation of SPA in farmland is not enough to secure species populations and has to be combined with agricultural policies and investment to maintain not only habitat availability but also habitat quality.

  3. [The decline in the population growth rate--a priority issue in international politics].

    Science.gov (United States)

    Rhein, E

    1994-08-25

    The Third International UN Conference on Population and Development took place in Cairo in early September 1994 with the participation of 200 governments and 1000 nongovernmental organizations to discuss ways of stabilizing world population at the possible lowest level and how industrialized countries could contribute to this effort. As a consequence of the advances in reproductive medicine the use of contraceptives skyrocketed: in 1994 more than half of men and women were using contraception compared to only 5% in 1950. However, the demographic momentum would still increase world population for another 100 years, even if fertility would drop to 2.2 children per couple (compared to 4 children in 1990). Nevertheless, the present generation could be instrumental in deciding whether the world's population will remain around 8 billion or reach 12 billion between 2050 and 2150. Poor countries can no longer afford an annual growth rate of 2-4% while also trying to improve living standards; this would require an economic growth rate of 6-8%. For the control of population growth both a sustainable environmental policy in the North, with rapid transition to renewable energy and recycling, and a more effective population policy in the South are needed. Family planning (FP) is the precondition of stabilization. The global FP outlays are envisioned to double from the 1994 figure of $5 billion to over $10 billion in the year 2000, with donor contributions to increase from 20% to 40% of the total. The US contribution is to double from $500 million by 2000, while the European Commission decided to boost expenditures for FP from DM 30 million in 1994 to DM 600 million by 2000. Japan is also expending $3 billion during this period. Recent promising developments have emerged: national pronatalist policies have diminished sharply and the pronatalist influence of religions has also declined. Political commitment at the highest level is central to a successful population policy as

  4. A Demographic Model to Evaluate Population Declines in the Endangered Streaked Horned Lark

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    Alaine F. Camfield

    2011-12-01

    Full Text Available The Streaked Horned Lark (Eremophila alpestris strigata is listed as endangered by the State of Washington, USA and by Canada under the Species at Risk Act and is also classified as a federal candidate for listing under the Endangered Species Act in the USA. A substantial portion of Streaked Horned Lark habitat has been lost or degraded, and range contraction has occurred in Oregon, Washington, and British Columbia. We estimate the vital rates (fecundity, adult and juvenile survival and population growth rate (λ for Streaked Horned Larks breeding in Washington, USA and conduct a Life-Stage Simulation Analysis (LSA to evaluate which vital rate has the greatest influence on λ. We simulated changes in the three vital rates to examine how much they would need to be adjusted either independently or in concert to achieve a stable Streaked Horned Lark population (λ = 1. We also evaluated which fecundity component (the number of fledglings per egg laid or renesting interval had the greatest impact on λ. The estimate of population growth suggests that Streaked Horned Larks in Washington are declining rapidly (λ = 0.62 ± 0.10 and that local breeding sites are not sustainable without immigration. The LSA results indicate that adult survival had the greatest influence on λ, followed by juvenile survival and fecundity. However, increases in vital rates led to λ = 1 only when adult survival was raised from 0.47 to 0.85, juvenile survival from 0.17 to 0.58, and fecundity from 0.91 to 3.09. Increases in breeding success and decreases in the renesting interval influenced λ similarly; however, λ did not reach 1 even when breeding success was raised to 100% or renesting intervals were reduced to 1 day. Only when all three vital rates were increased simultaneously did λ approach 1 without requiring highly unrealistic increases in each vital rate. We conclude that conservation activities need to target all or multiple vital rates to be successful. The

  5. Rapid population decline in red knots : fitness consequences of decreased refuelling rates and late arrival in Delaware Bay

    NARCIS (Netherlands)

    Baker, AJ; Gonzalez, PM; Piersma, T; Niles, LJ; do Nascimento, IDS; Atkinson, PW; Clark, NA; Minton, CDT; Peck, MK; Aarts, G

    2004-01-01

    Most populations of migrant shorebirds around the world are in serious decline, suggesting that vital condition-dependent rates such as fecundity and annual survival are being affected globally. A striking example is the red knot (Calidris canutus rufa) population wintering in Tierra del Fuego,

  6. Getting started in 3D with Maya

    CERN Document Server

    Watkins, Adam

    2012-01-01

    Deliver professional-level 3D content in no time with this comprehensive guide to 3D animation with Maya. With over 12 years of training experience, plus several award winning students under his belt, author Adam Watkins is the ideal mentor to get you up to speed with 3D in Maya. Using a structured and pragmatic approach Getting Started in 3D with Maya begins with basic theory of fundamental techniques, then builds on this knowledge using practical examples and projects to put your new skills to the test. Prepared so that you can learn in an organic fashion, each chapter builds on the know

  7. The use of population viability analysis to identify possible factors contributing to the decline of a rare ungulate population in south-eastern Zimbabwe

    Directory of Open Access Journals (Sweden)

    Simon D. Capon

    2013-02-01

    Full Text Available Populations that are vulnerable to decline are of particular concern to wildlife managers and uncovering the mechanisms responsible for downward trends is a crucial step towards developing future viable populations. The aims of this study were to better understand the mechanisms behind the historic decline of the sable antelope, Hippotragus niger, population at the Malilangwe Wildlife Reserve (MWR, to assess its future viability and to use this analysis to determine key areas of breakdown in population growth and link these to potential limiting factors. VORTEX, a population viability model was used to assess the future viability of the sable antelope population and a sensitivity analysis was applied to identify the key areas of breakdown in growth. The sable population is currently viable, but remains highly vulnerable to changes in adult female survival, a factor which had the greatest influence on overall population fitness. Lion predation, impacting on the adult segment of the population, appeared to be the main factor responsible for the historic decline at the MWR.Conservation implications: Sable generally occur at low densities in the lowveld region of Zimbabwe and, as such, populations are vulnerable to increases in mortality rates. The role of lions in driving the decline at the MWR suggests a need to control their numbers and develop prey refuges through improved management of artificial water.

  8. Sixty years of anthropogenic pressure: a spatio-temporal genetic analysis of brown trout populations subject to stocking and population declines

    DEFF Research Database (Denmark)

    Hansen, Michael Møller; Fraser, Dylan J.; Meier, Kristian

    2009-01-01

    Analyses of historical samples can provide invaluable information on changes to the genetic composition of natural populations resulting from human activities. Here, we analyse 21 microsatellite loci in historical (archived scales from 1927 to 1956) and contemporary samples of brown trout (Salmo...... trutta) from six neighbouring rivers in Denmark, to compare the genetic structure of wild populations before and after population declines and stocking with nonlocal strains of hatchery trout. We show that all populations have been strongly affected by stocking, with admixture proportions ranging from 14...... differences among populations in hatchery trout admixture proportions. Despite significant changes to the genetic composition within populations over time, dispersal rates among populations were roughly similar before and after stocking. We also assessed whether population declines or introgression...

  9. Local and global influences on population declines of coastal waders: Purple Sandpiper Calidris maritima numbers in the Moray Firth, Scotland

    Science.gov (United States)

    Summers, Ron W.; Foster, Simon; Swann, Bob; Etheridge, Brian

    2012-05-01

    Declines in numbers by several wader species in Britain have been linked to climate change, but the mechanism for the declines has rarely been explored. Britain lies at the northern end of the East Atlantic Flyway, and supports 1.3 million out of the Flyway's 8.5 million coastal waders (Charadrii) in winter and the Purple Sandpiper is one of the species whose numbers have declined. Here, we examine the dynamics of the decline as observed in the Moray Firth, northeast Scotland, investigating whether the decline was due to poorer apparent survival (return rate) or poorer recruitment of young birds. The maximum number in the Moray Firth declined from 860 in 1987/88 to 236 in 2006/07, with some increase during winters 2007/08 and 2008/09. At the three main high-tide roosts (Balintore, Lossiemouth and Buckie) the maximum combined number declined from 574 to 90. Changes in survival and recruitment (percentage of first-year birds) were examined at these roosts from captured samples, which were ringed and recaptured. There were no significant changes between winters in survival rates, nor were there differences between the survival rates of age groups (first-year and adult) or bill size groups, which represented birds of different sex and breeding origin. Annual survival estimates for the three roosts ranged from 72 to 77%. The percentage of first-year birds varied among roosts and years; the lowest values were during the late 1980s/early 1990s and early 2000s. A free-running population model incorporating varying percentages of first-year birds and constant mortality for each roost provided a plausible explanation for the decline. Although modelled numbers followed the observed pattern, a discrepancy in one year was carried forward in subsequent years, so that the fit with the observed numbers was parallel rather than similar. However, it seems that the decline in numbers was largely due to poorer recruitment. We discuss whether breeding success had declined, whether the

  10. Pathogens, nutritional deficiency, and climate influences on a declining moose population

    Science.gov (United States)

    Murray, D.L.; Cox, E.W.; Ballard, W.B.; Whitlaw, Heather A.; Lenarz, M.S.; Custer, T.W.; Barnett, T.; Fuller, T.K.

    2006-01-01

    Several potential proximate causes may be implicated in a recent (post-1984) decline in moose (Alces alces andersoni) numbers at their southern range periphery in northwest Minnesota, USA. These causes include deleterious effects of infectious pathogens, some of which are associated with white-tailed deer (Odocoileus virginianus), negative effects of climate change, increased food competition with deer or moose, legal or illegal hunting, and increased predation by gray wolves (Canis lupus) and black bears (Ursus americanus). Long-standing factors that may have contributed to the moose decline include those typically associated with marginal habitat such as nutritional deficiencies. We examined survival and productivity among radiocollared (n = 152) adult female and juvenile moose in northwest Minnesota during 1995–2000, and assessed cause of death and pathology through carcass necropsy of radiocollared and non-radiocollared animals.Aerial moose surveys suggested that hunting was an unlikely source of the numerical decline because the level of harvest was relatively low (i.e., approx. 15% / 2 yr) and the population usually grew in years following a hunt. The majority of moose mortalities (up to 87% of radiocollared moose [n = 76] and up to 65% of non-radiocollared moose [n = 84]) were proximally related to pathology associated with parasites and infectious disease. Liver fluke (Fascioloides magna) infections apparently constituted the greatest single source of mortality and caused significant pathology in the liver, thoracic and peritoneal cavities, pericardial sac, and lungs. Mortality due to meningeal worm (Parelaphostrongylus tenuis) was less prevalent and was manifested through characteristic neurological disease. Several mortalities apparently were associated with unidentified infectious disease, probably acting in close association with malnutrition. Bone-marrow fat was lower for moose dying of natural causes than those dying of anthropogenic factors or

  11. Acculturation stress among Maya in the United States.

    Science.gov (United States)

    Millender, Eugenia

    2012-01-01

    Abstract: As health care disparities become more evident in our multicultural nation, culture sensitive health research needs to be a priority in order for good health care to take place. This article will explore the literature related to acculturation stress and mental health disparities among the Mayan population. Literatures of similar but distinct groups are included due to the limited amount of research of the Mayan population. Using Leiniger's Transcultural nursing theory, these findings suggest that nurses have a large gap to fill to address the mental health disparities of specific cultural groups like the indigenous Maya, thereby satisfying their nursing obligations.

  12. Projected risk of population declines for native fish species in the Upper Mississippi River

    Science.gov (United States)

    Crimmins, S.M.; Boma, P.; Thogmartin, W.E.

    2015-01-01

    Conservationists are in need of objective metrics for prioritizing the management of habitats. For individual species, the threat of extinction is often used to prioritize what species are in need of conservation action. Using long-term monitoring data, we applied a Bayesian diffusion approximation to estimate quasi-extinction risk for 54 native fish species within six commercial navigation reaches along a 1350-km gradient of the upper Mississippi River system. We found a strong negative linear relationship between quasi-extinction risk and distance upstream. For some species, quasi-extinction estimates ranged from nearly zero in some reaches to one in others, suggesting substantial variability in threats facing individual river reaches. We found no evidence that species traits affected quasi-extinction risk across the entire system. Our results indicate that fishes within the upper Mississippi River system face localized threats that vary across river impact gradients. This suggests that conservation actions should be focused on local habitat scales but should also consider the additive effects on downstream conditions. We also emphasize the need for identification of proximate mechanisms behind observed and predicted population declines, as conservation actions will require mitigation of such mechanisms. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  13. Landscape Archeology: Remote Sensing Investigation of the Ancient Maya in the Peten Rainforest of Northern Guatemala

    Science.gov (United States)

    Sever, Thomas L.; Irwin, Daniel E.; Arnold, James E. (Technical Monitor)

    2002-01-01

    Through the use of airborne and satellite imagery we are improving our ability to investigate ancient Maya settlement, subsistence, and landscape modification in this dense forest region. Today the area is threatened by encroaching settlement and deforestation. However, it was in this region that the Maya civilization began, flourished, and abruptly disappeared for unknown reasons in the 9th century AD. At the time of their collapse they had attained one of the highest population densities in human history. How the Maya were able to successfully manage water and feed this dense population is not well understood at this time. A NASA-funded project used remote sensing technology to investigate large seasonal swamps (bajos) that make up 40 percent of the landscape. Through the use of remote sensing, ancient Maya features such as sites, roadways, canals and water reservoirs have been detected and verified through ground reconnaissance. The results of this preliminary research cast new light on the adaptation of the ancient Maya to their environment. Microenvironmental variation within the wetlands was elucidated and the different vegetation associations identified in the satellite imagery. More than 70 new archeological sites within and at the edges of the bajo were mapped and tested. Modification of the landscape by the Maya in the form of dams and reservoirs in the Holmul River and its tributaries and possible drainage canals in bajos was demonstrated. The use of Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM), one-meter IKONOS satellite imagery, as well as high resolution airborne STAR-3i radar imagery--2.5 meter backscatter/10 meter Digital Elevation Model (DEM)--are opening new possibilities for understanding how a civilization was able to survive for centuries upon a karat topographic landscape. This understanding is critical for the current population that is currently experiencing rapid population growth and destroying the landscape through

  14. Genomic insights on the ethno-history of the Maya and the 'Ladinos' from Guatemala.

    Science.gov (United States)

    Söchtig, Jens; Álvarez-Iglesias, Vanesa; Mosquera-Miguel, Ana; Gelabert-Besada, Miguel; Gómez-Carballa, Alberto; Salas, Antonio

    2015-02-25

    Guatemala is a multiethnic and multilingual country located in Central America. The main population groups separate 'Ladinos' (mixed Native American-African-Spanish), and Native indigenous people of Maya descent. Among the present-day Guatemalan Maya, there are more than 20 different ethnic groups separated by different languages and cultures. Genetic variation of these communities still remains largely unexplored. The principal aim of this study is to explore the genetic variability of the Maya and 'Ladinos' from Guatemala by means of uniparental and ancestry informative markers (AIMs). Analyses of uniparental genetic markers indicate that Maya have a dominant Native American ancestry (mitochondrial DNA [mtDNA]: 100%; Y-chromosome: 94%). 'Ladino', however, show a clear gender-bias as indicated by the large European ancestry observed in the Y-chromosome (75%) compared to the mtDNA (0%). Autosomal polymorphisms (AIMS) also mirror this marked gender-bias: (i) Native American ancestry: 92% for the Maya vs. 55% for the 'Ladino', and (ii) European ancestry: 8% for the Maya vs. 41% for the 'Ladino'. In addition, the impact of the Trans-Atlantic slave trade on the present-day Guatemalan population is very low (and only occurs in the 'Ladino'; mtDNA: 9%; 4%), in part mirroring the fact that Guatemala has a predominant orientation to the Pacific Ocean instead of a Caribbean one. Sequencing of entire Guatemalan mitogenomes has led to improved Native American phylogeny via the addition of new haplogroups that are mainly observed in Mesoamerica and/or the North of South America. The data reveal the existence of a fluid gene flow in the Mesoamerican area and a predominant unidirectional flow towards South America, most likely occurring during the Pre-Classic (1800 BC-200 AD) and the Classic (200-1000 AD) Eras of the Mesoamerican chronology, coinciding with development of the most distinctive and advanced Mesoamerican civilization, the Maya. Phylogenetic features of mtDNA data

  15. Finds in Belize document Late Classic Maya salt making and canoe transport

    Science.gov (United States)

    McKillop, Heather

    2005-01-01

    How did people in preIndustrial ancient civilizations produce and distribute bulk items, such as salt, needed for everyday use by their large urban populations? This report focuses on the ancient Maya who obtained quantities of salt at cities in the interior of the Yucatan peninsula of Mexico, Belize, and Guatemala in an area where salt is scarce. I report the discovery of 41 Late Classic Maya saltworks (anno Domini 600–900) in Punta Ycacos Lagoon on the south coast of Belize, including one with the first-known ancient Maya canoe paddle. The discoveries add important empirical information for evaluating the extent of surplus salt production and river transport during the height of Late Classic civilization in the southern Maya lowlands. The discovery of the saltworks indicates that there was extensive production and distribution of goods and resources outside the cities in the interior of the Yucatan. The discovery of a wooden canoe paddle from one of the Punta Ycacos saltworks, Ka'k' Naab', ties the production of salt to its inland transport by rivers and documents the importance of canoe trade between the coast and the interior during the Late Classic. Archaeological discovery of multiple saltworks on the Belizean coast represents surplus production of salt destined largely for the inland Peten Maya during their Late Classic peak, underscoring the importance of non-state-controlled workshop production in preIndustrial societies. PMID:15809426

  16. Genetic Diversity of Plasmodium falciparum Populations in Malaria Declining Areas of Sabah, East Malaysia.

    Directory of Open Access Journals (Sweden)

    Mohd Ridzuan Mohd Abd Razak

    .532. The genetic data from the present study highlighted the limited diversity and contrasting genetic pattern of P. falciparum populations in the malaria declining areas of Sabah.

  17. Is the current decline in malaria burden in sub-Saharan Africa due to a decrease in vector population?

    Directory of Open Access Journals (Sweden)

    Rwegoshora Rwehumbiza T

    2011-07-01

    Full Text Available Abstract Background In sub-Saharan Africa (SSA, malaria caused by Plasmodium falciparum has historically been a major contributor to morbidity and mortality. Recent reports indicate a pronounced decline in infection and disease rates which are commonly ascribed to large-scale bed net programmes and improved case management. However, the decline has also occurred in areas with limited or no intervention. The present study assessed temporal changes in Anopheline populations in two highly malaria-endemic communities of NE Tanzania during the period 1998-2009. Methods Between 1998 and 2001 (1st period and between 2003 and 2009 (2nd period, mosquitoes were collected weekly in 50 households using CDC light traps. Data on rainfall were obtained from the nearby climate station and were used to analyze the association between monthly rainfall and malaria mosquito populations. Results The average number of Anopheles gambiae and Anopheles funestus per trap decreased by 76.8% and 55.3%, respectively over the 1st period, and by 99.7% and 99.8% over the 2nd period. During the last year of sampling (2009, the use of 2368 traps produced a total of only 14 Anopheline mosquitoes. With the exception of the decline in An. gambiae during the 1st period, the results did not reveal any statistical association between mean trend in monthly rainfall and declining malaria vector populations. Conclusion A longitudinal decline in the density of malaria mosquito vectors was seen during both study periods despite the absence of organized vector control. Part of the decline could be associated with changes in the pattern of monthly rainfall, but other factors may also contribute to the dramatic downward trend. A similar decline in malaria vector densities could contribute to the decrease in levels of malaria infection reported from many parts of SSA.

  18. Waist Circumference, Not Body Mass Index, Is Associated with Renal Function Decline in Korean Population: Hallym Aging Study

    Science.gov (United States)

    Oh, Hyunju; Quan, Shan Ai; Jeong, Jin-Young; Jang, Soong-Nang; Lee, Jung Eun; Kim, Dong-Hyun

    2013-01-01

    Background Prospective investigation of obesity and renal function decline in Asia is sparse. We examined the associations of body mass index (BMI) and waist circumference (WC) with renal function decline in a prospective study of Korean population. Methods A total of 454 participants who had baseline estimated glomerular filtration rate (eGFR) levels of more than 60 mL/min/1.73 m2 in Hallym Aging Study (HAS) were included and followed for 6 years. Renal function decline was defined as follows: (1) an eGFR decline ≥3 mL/min/1.73 m2/year (n = 82 cases); (2) an eGFR decrease of 20% or greater (n = 87 cases) at follow-up; (3) an eGFR decrease of 20% greater at follow-up or eGFR decline ≥3 mL/min/1.73 m2/year (n = 91 cases); and (4) an eGFR 95 cm in men or >90 cm in women with ≤90 cm in men or ≤85 cm in women, ORs (95% CIs) ranged from 2.31 (1.14–4.69) to 2.78 (1.19–6.50) for the 4 definitions of renal function decline (all p-values for trend Korean population. Our results provide important evidence that simple measurement of central fat deposition rather than BMI could predict decline in renal function in Korean population. PMID:23536858

  19. Is the current decline in malaria burden in sub-Saharan Africa due to a decrease in vector population?

    DEFF Research Database (Denmark)

    Meyrowitsch, Dan Wolf; Pedersen, Erling Møller; Alifrangis, Michael

    2011-01-01

    ) and between 2003 and 2009 (2nd period), mosquitoes were collected weekly in 50 households using CDC light traps. Data on rainfall were obtained from the nearby climate station and was used to analyze the association between monthly rainfall and malaria mosquito populations. RESULTS: The average number...... of Anopheles gambiae and Anopheles funestus per trap decreased by 76.8% and 55.3%, respectively over the 1st period, and by 99.7% and 99.8% over the 2nd period. During the last year of sampling (2009), the use of 2368 traps produced a total of only 14 Anopheline mosquitoes. With the exception of the decline...... in An. gambiae during the 1st period, the results did not reveal any statistical association between mean trend in monthly rainfall and declining malaria vector populations. CONCLUSION: A longitudinal decline in the density of malaria mosquito vectors was seen during both study periods despite...

  20. Sudden deaths and colony population decline in Greek honey bee colonies.

    Science.gov (United States)

    Bacandritsos, N; Granato, A; Budge, G; Papanastasiou, I; Roinioti, E; Caldon, M; Falcaro, C; Gallina, A; Mutinelli, F

    2010-11-01

    During June and July of 2009, sudden deaths, tremulous movements and population declines of adult honey bees were reported by the beekeepers in the region of Peloponnesus (Mt. Mainalo), Greece. A preliminary study was carried out to investigate these unexplained phenomena in this region. In total, 37 bee samples, two brood frames containing honey bee brood of various ages, eight sugar samples and four sugar patties were collected from the affected colonies. The samples were tested for a range of pests, pathogens and pesticides. Symptomatic adult honey bees tested positive for Varroa destructor, Nosema ceranae, Chronic bee paralysis virus (CBPV), Acute paralysis virus (ABPV), Deformed wing virus (DWV), Sacbrood virus (SBV) and Black queen cell virus (BQCV), but negative for Acarapis woodi. American Foulbrood was absent from the brood samples. Chemical analysis revealed that amitraz, thiametoxan, clothianidin and acetamiprid were all absent from symptomatic adult bees, sugar and sugar patty samples. However, some bee samples, were contaminated with imidacloprid in concentrations between 14 ng/g and 39 ng/g tissue. We present: the infection of Greek honey bees by multiple viruses; the presence of N. ceranae in Greek honey bees and the first record of imidacloprid (neonicotonoid) residues in Greek honey bee tissues. The presence of multiple pathogens and pesticides made it difficult to associate a single specific cause to the depopulation phenomena observed in Greece, although we believe that viruses and N. ceranae synergistically played the most important role. A follow-up in-depth survey across all Greek regions is required to provide context to these preliminary findings. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Fewer but not smaller schools in declining fish and krill populations.

    Science.gov (United States)

    Brierley, Andrew S; Cox, Martin J

    2015-01-05

    Many pelagic species (species that live in the water column), including herring and krill, aggregate to form schools, shoals, or swarms (hereafter simply "schools," although the words are not synonyms). Schools provide benefits to individual members, including locomotory economy and protection from predators that prey on individuals, but paradoxically make schooling species energetically viable and commercially attractive targets for predators of groups and for fishers. Large schools are easier to find and yield greater prey/catch than small schools, and there is a requirement from fields as diverse as theoretical ecology and fisheries management to understand whether and how aggregation sizes change with changing population size. We collated data from vertical echosounder surveys of taxonomically diverse pelagic stocks from geographically diverse ecosystems. The data contain common significant positive linear stock-biomass to school-number relationships. They show that the numbers of schools in the stocks change with changing stock biomass and suggest that the distributions of school sizes do not change with stock biomass. New data that we collected using a multibeam sonar, which can image entire schools, contained the same stock-biomass to school-number relationship and confirm that the distribution of school sizes is not related to changing stock size: put simply, as stocks decline, individuals are distributed among fewer schools, not smaller schools. Since school characteristics affect catchability (the ease or difficulty with which fishers can capture target species) and availability of prey to predators, our findings have commercial and ecological implications, particularly within the aspirational framework of ecosystem-based management of marine systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Genetic structure and evidence for recent population decline in Eurasian otter populations in the Czech and Slovak Republics: implications for conservation

    DEFF Research Database (Denmark)

    Hájková, P.; Pertoldi, C.; Ukendt, Zemanová

    2007-01-01

    Over the latter part of the 20th century, Eurasian otter Lutra lutra populations suffered dramatic declines, resulting in extinction or fragmentation of populations in many western and central European countries. Part of the Czech otter population became totally isolated while the Slovak populati...... that they remain a strongly protected species in both countries. The spreading and re-connection of otter populations observed recently is essential for the future health of the populations, and should be supported through habitat conservation......., suggesting that the strongest decline probably occurred between the 1970s and the mid-1990s. The results of this study confirm that otter populations remain vulnerable to any violent demographic change and, despite the claims of fish-farmers and anglers for legal culls, it is highly desirable...

  3. Airborne Pesticides as an Unlikely Cause for Population Declines of Alpine Frogs in the Sierra Nevada, California

    Science.gov (United States)

    Airborne pesticides from the Central Valley of California have been implicated as a cause for population declines of several amphibian species, with the strongest evidence for the mountain yellow-legged frog complex (Rana muscosa and R. sierrae) in the Sierra Nevada. We measured...

  4. Daily life of the ancient Maya recorded on murals at Calakmul, Mexico

    Science.gov (United States)

    Carrasco Vargas, Ramón; López, Verónica A. Vázquez; Martin, Simon

    2009-01-01

    Research into ancient societies frequently faces a major challenge in accessing the lives of those who made up the majority of their populations, since the available evidence so often concerns only the ruling elite. Our excavations at the ancient Maya site of Calakmul, Mexico, have uncovered a “painted pyramid:” a structure decorated with murals depicting scenes of its inhabitants giving, receiving, and consuming diverse foods, as well as displaying and transporting other goods. Many are accompanied by hieroglyphic captions that describe the participants, and include spellings of key subsistence items. Collectively, they offer insights into the social mechanisms by which goods were circulated within major Maya centers. PMID:19901331

  5. Documenting and explaining the HIV decline in east Zimbabwe: the Manicaland General Population Cohort.

    Science.gov (United States)

    Gregson, Simon; Mugurungi, Owen; Eaton, Jeffrey; Takaruza, Albert; Rhead, Rebecca; Maswera, Rufurwokuda; Mutsvangwa, Junior; Mayini, Justin; Skovdal, Morten; Schaefer, Robin; Hallett, Timothy; Sherr, Lorraine; Munyati, Shungu; Mason, Peter; Campbell, Catherine; Garnett, Geoffrey P; Nyamukapa, Constance Anesu

    2017-10-06

    The Manicaland cohort was established to provide robust scientific data on HIV prevalence and incidence, patterns of sexual risk behaviour and the demographic impact of HIV in a sub-Saharan African population subject to a generalised HIV epidemic. The aims were later broadened to include provision of data on the coverage and effectiveness of national HIV control programmes including antiretroviral therapy (ART). General population open cohort located in 12 sites in Manicaland, east Zimbabwe, representing 4 major socioeconomic strata (small towns, agricultural estates, roadside settlements and subsistence farming areas). 9,109 of 11,453 (79.5%) eligible adults (men 17-54 years; women 15-44 years) were recruited in a phased household census between July 1998 and January 2000. Five rounds of follow-up of the prospective household census and the open cohort were conducted at 2-year or 3-year intervals between July 2001 and November 2013. Follow-up rates among surviving residents ranged between 77.0% (over 3 years) and 96.4% (2 years). HIV prevalence was 25.1% at baseline and had a substantial demographic impact with 10-fold higher mortality in HIV-infected adults than in uninfected adults and a reduction in the growth rate in the worst affected areas (towns) from 2.9% to 1.0%pa. HIV infection rates have been highest in young adults with earlier commencement of sexual activity and in those with older sexual partners and larger numbers of lifetime partners. HIV prevalence has since fallen to 15.8% and HIV incidence has also declined from 2.1% (1998-2003) to 0.63% (2009-2013) largely due to reduced sexual risk behaviour. HIV-associated mortality fell substantially after 2009 with increased availability of ART. We plan to extend the cohort to measure the effects on the epidemic of current and future HIV prevention and treatment programmes. Proposals for access to these data and for collaboration are welcome. © Article author(s) (or their employer(s) unless otherwise

  6. Has contemporary climate change played a role in population declines of the lizard Ctenophorus decresii from semi-arid Australia?

    Science.gov (United States)

    Walker, Samantha; Stuart-Fox, Devi; Kearney, Michael R

    2015-12-01

    Whilst contemporary climatic changes are small in magnitude compared to those predicted for the coming decades, they have already been linked to species range shifts and local extinctions. Elucidating the drivers behind species' responses to contemporary climate change will better inform management strategies for vulnerable and pest species alike. A recent proposal to explain worldwide local extinctions in lizards is that increasing maximum temperatures have constrained lizard activity time in the breeding season beyond extinction thresholds. Here we document a significant population decline and potential local extinction at the warm (northern) range margin of the tawny dragon, Ctenophorus decresii, a rock-dwelling lizard from the Flinders Ranges in semi-arid Australia. We developed and tested a biophysical model of tawny dragon thermoregulatory behaviour and drove the model with daily weather data for the period 1990-2009 across the Flinders Ranges. Our results indicate that potential annual activity time has likely increased over this period throughout the historic range, with within-season declines only in the summer months at the northern range limit. However, populations that have declined since 2000 have also likely experienced higher active body temperatures and more stringent retreat-site requirements (deeper crevices) than have regions where the species remains common, during a period of declining rainfall. Our laboratory estimates of thermal preference in this species were insensitive to altered nutritional and hydric state. Thus it is possible that recent population declines are linked to desiccation stress driven by higher body temperatures and declining rainfall. Our study illustrates that simple indices of the impact of climate warming on animals, such as activity restriction, may in fact reflect a variety of potential mechanisms whose ultimate outcome will be contingent on other factors such as water and shelter availability. Copyright © 2014

  7. Ownership of Language in Yucatec Maya Revitalization Pedagogy

    Science.gov (United States)

    Guerrettaz, Anne Marie

    2015-01-01

    This classroom-based study examined a Yucatec Maya language course for teachers and the pedagogical implementation of national language policy in Mexico. Analysis of this teacher education program focused on various dimensions of teachers' Maya-language expertise, the teaching of the emergent standard Maya, and hegemonic constructions of…

  8. Linking temporal changes in the demographic structure and individual growth to the decline in the population of a tropical fish

    Science.gov (United States)

    Sirot, Charlotte; Darnaude, Audrey M.; Guilhaumon, François; Ramos-Miranda, Julia; Flores-Hernandez, Domingo; Panfili, Jacques

    2015-11-01

    The exceptional biodiversity and productivity of tropical coastal lagoons can only be preserved by identifying the causes for the decline in the populations living in these vulnerable ecosystems. The Terminos lagoon in Mexico provided an opportunity for studying this issue as some of its fish populations, in particular the Silver Perch (Bairdiella chrysoura), have declined significantly since the 1980s. Fish sampling campaigns carried out over the whole lagoon area in 1979-81 and again in 2006-2011 revealed the mechanisms which may have been responsible for this decline. Based on biometrical data for 295 juveniles and adults from the two periods and on somatic growth derived from 173 otoliths, a study of the temporal changes in the demographic structure and life history traits (individual growth and body condition) made it possible to distinguish the causes of the decline in the B. chrysoura population. Growth models for the lagoon in 1980-1981 and 2006-2011 showed no significant change in the growth parameters of the population over the last 30 years with a logistic model giving an accurate estimate (R2 = 0.66) of the size-at-age for both periods. The decline in the B. chrysoura population could not be explained by an overall decrease in individual size and condition in the lagoon, the average standard length (SL) and Fulton index (FI) having increased slightly since 1980-1981 (4.6 mm and 0.02 for juveniles and 5.42 mm and 0.07 for adults). However, the size structure of the population in the lagoon has changed, with a significant shift in the size distribution of juveniles with a marked reduction in the proportion of juveniles ≤ 60 mm in the captures (90.9% fewer than in 1980-1981). As the otolith growth rate of fish during the first 4 months also decreased significantly between the two sampling periods (-15%), it is suggested that the main reason for the decline in the abundance and biomass of B. chrysoura within this system may be that its habitats are less

  9. The population decline of Gyps vultures in India and Nepal has slowed since veterinary use of diclofenac was banned.

    Directory of Open Access Journals (Sweden)

    Vibhu Prakash

    Full Text Available Populations of oriental white-backed vulture (Gyps bengalensis, long-billed vulture (Gyps indicus and slender-billed vulture (Gyps tenuirostris crashed during the mid-1990s throughout the Indian subcontinent. Surveys in India, initially conducted in 1991-1993 and repeated in 2000, 2002, 2003 and 2007, revealed that the population of Gyps bengalensis had fallen by 2007 to 0.1% of its numbers in the early 1990s, with the population of Gyps indicus and G. tenuirostris combined having fallen to 3.2% of its earlier level. A survey of G. bengalensis in western Nepal indicated that the size of the population in 2009 was 25% of that in 2002. In this paper, repeat surveys conducted in 2011 were analysed to estimate recent population trends. Populations of all three species of vulture remained at a low level, but the decline had slowed and may even have reversed for G. bengalensis, both in India and Nepal. However, estimates of the most recent population trends are imprecise, so it is possible that declines may be continuing, though at a significantly slower rate. The degree to which the decline of G. bengalensis in India has slowed is consistent with the expected effects on population trend of a measured change in the level of contamination of ungulate carcasses with the drug diclofenac, which is toxic to vultures, following a ban on its veterinary use in 2006. The most recent available information indicates that the elimination of diclofenac from the vultures' food supply is incomplete, so further efforts are required to fully implement the ban.

  10. Effect of Early Referral to Specialist in Dementia on Institutionalization and Functional Decline: Findings from a Population-Based Study.

    Science.gov (United States)

    Pimouguet, Clément; Le-Goff, Mélanie; Rizzuto, Debora; Berr, Claudine; Leffondré, Karen; Pérès, Karine; Dartigues, Jean FranÇois; Helmer, Catherine

    2016-01-01

    Although early diagnosis has been hypothesized to benefit both patients and caregivers, until now studies evaluating the effect of early dementia diagnosis are lacking. To investigate the influence of early specialist referral for dementia on the risk of institutionalization and functional decline in Activity of Daily Living (ADL). Incident dementia cases were screened in a prospective population-based cohort, the Three-City Study, and initial specialist consultation for cognitive complaint was assessed at dementia diagnosis. Proportional hazard regression and illness-death models were used to test the association between specialist referral and, respectively, institutionalization and functional decline. Only one third of the incident individuals with dementia had consulted a specialist for cognitive problems early (36%). After adjustment on potential confounders (including cognitive and functional decline) and competing risk of death, participants who had consulted a specialist early in the disease course presented a higher rate of being institutionalized than those who did not (Hazard Ratio = 2.00, 95% Confidence Interval (CI): 1.09- 3.64). But early specialist referral was not associated with further functional decline (HR = 1.09, 95% CI: 0.71- 1.67). Early specialist referral in dementia is associated with increased risk of institutionalization but not with functional decline in ADL. These findings suggest that early care referral in dementia may be a marker of concern for patients and/or caregivers; subsequent medical and social care could be suboptimal or inappropriate to allow patients to stay longer at home.

  11. The use of population viability analysis to identify possible factors contributing to the decline of a rare ungulate population in south-eastern Zimbabwe

    Directory of Open Access Journals (Sweden)

    Simon D. Capon

    2013-04-01

    Conservation implications: Sable generally occur at low densities in the lowveld region of Zimbabwe and, as such, populations are vulnerable to increases in mortality rates. The role of lions in driving the decline at the MWR suggests a need to control their numbers and develop prey refuges through improved management of artificial water.

  12. On the decline of the Rusty Blackbird and the use of ornithological literature to document long-term population trends

    Science.gov (United States)

    Greenberg, R.; Droege, S.

    1999-01-01

    Unlike most North American blackbirds, Rusty Blackbirds (Euphagus carolensis) have shown steep population declines. Declines of approximately 90% are indicated for three recent decades from the Breeding Bird Survey, Christmas Bird Counts, and Quebec Checklist Program. Analyses of abundance classifications in bird distribution books and annotated checklists reveal an overlooked but long-term decline dating back to at least the early part of this century. Rusty Blackbirds were described as very common to abundant in 5656 of the pre-192O published accounts, 19% of the 1921-1950 accounts, and only 7% of the post-1950 accounts. Rusty Blackbirds were described as uncommon in none of the pre-1950 accounts, 18% of the 1951-1980 accounts, and 43% of the post-1980 accounts. A similar pattern was found for analyses based on local checklists. Destruction of wooded wetlands on wintering grounds, acid precipitation, and the conversion of boreal forest wetlands could have contributed to these declines. Systematic analysis of regional guides and checklists provides a valuable tool for examining large-scale and long-term population changes in birds.

  13. Detection and effects of harmful algal toxins in Scottish harbour seals and potential links to population decline.

    Science.gov (United States)

    Jensen, Silje-Kristin; Lacaze, Jean-Pierre; Hermann, Guillaume; Kershaw, Joanna; Brownlow, Andrew; Turner, Andrew; Hall, Ailsa

    2015-04-01

    Over the past 15 years or so, several Scottish harbour seal (Phoca vitulina) populations have declined in abundance and several factors have been considered as possible causes, including toxins from harmful algae. Here we explore whether a link could be established between two groups of toxins, domoic acid (DA) and saxitoxins (STXs), and the decline in the harbour seal populations in Scotland. We document the first evidence that harbour seals are exposed to both DA and STXs from consuming contaminated fish. Both groups of toxins were found in urine and faeces sampled from live captured (n = 162) and stranded animals (n = 23) and in faecal samples collected from seal haul-out sites (n = 214) between 2008 and 2013. The proportion of positive samples and the toxins levels measured in the excreta were significantly higher in areas where harbour seal abundance is in decline. There is also evidence that DA has immunomodulatory effects in harbour seals, including lymphocytopenia and monocytosis. Scottish harbour seals are exposed to DA and STXs through contaminated prey at potentially lethal levels and with this evidence we suggest that exposure to these toxins are likely to be important factors driving the harbour seal decline in some regions of Scotland. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. The effect of new business creation on employment growth in regions facing population decline

    NARCIS (Netherlands)

    Delfmann, Heike; Koster, Sierdjan

    Particularly in declining regions, new businesses creation is seen as a means to secure (future) employment opportunities. However, the way in which new business creation exerts its influence on employment is not evident. Do start-ups in these areas influencing employment change as they do in growth

  15. MAYAS, SPIRITUALITY, AND THE UNFINISHED HISTORY OF CONFLICT IN GUATEMALA.

    Directory of Open Access Journals (Sweden)

    Servando Z. Hinojosa

    2012-10-01

    Full Text Available Maya spiritual practice in Guatemala has been actively challenged by mainstream religions and by pressures originating from other institutions. Many Maya ritualists have been directly reproached by religious leaders and have been targeted by a state apparatus that associates rural Maya life with insurgency. As a result, many Maya spiritual elements have been pushed to, and kept at, the margins of society. Focusing on the past two decades, this essay reviews how Mayas nevertheless maintain an active ritual life. They do this by engaging in a close relationship with the spirit-owners of the landscape, beings upon whom humans depend for their sustenance and life. They do this, also, in the face of many challenges from organized religions, the educational system, and the military. Having considered the effects of these institutions upon Maya spirituality, I then put forward some concerns Mayas face when addressing how to value and promote Maya spiritual practices in Guatemala. In addition to encouraging young Mayas to uphold their heritage, Mayas may need to prevail upon Catholic and evangelical Protestant congregations to suspend judgment about Maya spirituality and to acknowledge its far-reaching importance in culturally pluralistic society.

  16. A late Holocene tephrochronology for the Maya Lowlands, Central America

    Science.gov (United States)

    Nooren, K.; Huizinga, A.; Hoek, W.; Bergen, M. V.; Middelkoop, H.

    2012-12-01

    The Maya Lowlands in southern Mexico, Guatemala and Belize were densely populated for thousands of years, and have been the subject of intensive studies on the interaction between humans and their environment. Accurate radiocarbon dating of proxy records and disrupting events has proved to be difficult due to the lack of organic material in many deposits and the 'old carbon effect' related to the calcareous geology of the Yucatan Peninsula. So far, tephrostratigraphy has hardly been used to define time markers for palynological, limnological and archaeological studies in this region, despite the frequent occurrence of tephra fall. With the objective to fill this gap, we developed a tephrochronology for the Maya Lowlands using sediment cores from a flood basin of the Usumacinta-Grijalva delta in southern Mexico. Tephrostratigraphy and radiocarbon dating were used to estimate the timing of past volcanic eruptions, and chemical compositions of glass shards were used to identify potential sources. At least six tephralayers were deposited since 2000 BC, the most notable representing eruptions of El Chichón volcano in the 5th and 15th century AD. The high sulphur emissions accompanying El Chichón's eruptions allowed testing of our age-depth model through a correlation with volcanic sulphate peaks in ice cores from Greenland and Antarctica. We demonstrate the applicability of the established tephrochronological framework in a detailed chronological reconstruction of the formation of the world's largest late Holocene beach ridge plain in southern Mexico. This plain with over 500 beach ridges is a highly sensitive recorder of combined sea level rise, subsidence, storm activity and changes in climate and upstream land use since the dawn of Olmec and Maya cultures circa 5000 years ago.

  17. Poetizas mayas:subjetividades contra la corriente

    OpenAIRE

    Maya, Gloria Chacón

    2013-01-01

    Este ensayo examina la emergencia de poetisas mayas en México y Guatemala como parte de un movimiento indígena ás amplio que clama su derecho a la diferencia cultural. Arguyo que aunque la mujer maya está inmersa en los discursos del nacionalismo oficial, nacionalismos étnicos y feminismos occidentales, crea sus propias subjetividades multidimensionales, vía la poesía. El análisis se enfoca en la resignificación de símbolos culturales tradicionales y la negociación de cultura, poder y género....

  18. Maya Studio Projects Texturing and Lighting

    CERN Document Server

    Lanier, Lee

    2011-01-01

    Learn to create realistic digital assets for film and games with this project-based guide Focused entirely on practical projects, this hands-on guide shows you how to use Maya's texturing and lighting tools in real-world situations. Whether you need to sharpen your skills or you're looking to break into the field for the first time, you'll learn top industry techniques for this important skill as you follow the instructions for several specific projects. You can even create your own version, using final Maya scene files to validate results. The companion DVD includes supplemental videos, proje

  19. Cacao usage by the earliest Maya civilization.

    Science.gov (United States)

    Hurst, W Jeffrey; Tarka, Stanley M; Powis, Terry G; Valdez, Fred; Hester, Thomas R

    2002-07-18

    The Maya archaeological site at Colha in northern Belize, Central America, has yielded several spouted ceramic vessels that contain residues from the preparation of food and beverages. Here we analyse dry residue samples by using high-performance liquid chromatography coupled to atmospheric-pressure chemical-ionization mass spectrometry, and show that chocolate (Theobroma cacao) was consumed by the Preclassic Maya as early as 600 bc, pushing back the earliest chemical evidence of cacao use by some 1,000 years. Our application of this new and highly sensitive analytical technique could be extended to the identification of other ancient foods and beverages.

  20. The utility of estimating population-level trajectories of terminal wellbeing decline within a growth mixture modelling framework.

    Science.gov (United States)

    Burns, R A; Byles, J; Magliano, D J; Mitchell, P; Anstey, K J

    2015-03-01

    Mortality-related decline has been identified across multiple domains of human functioning, including mental health and wellbeing. The current study utilised a growth mixture modelling framework to establish whether a single population-level trajectory best describes mortality-related changes in both wellbeing and mental health, or whether subpopulations report quite different mortality-related changes. Participants were older-aged (M = 69.59 years; SD = 8.08 years) deceased females (N = 1,862) from the dynamic analyses to optimise ageing (DYNOPTA) project. Growth mixture models analysed participants' responses on measures of mental health and wellbeing for up to 16 years from death. Multi-level models confirmed overall terminal decline and terminal drop in both mental health and wellbeing. However, modelling data from the same participants within a latent class growth mixture framework indicated that most participants reported stability in mental health (90.3 %) and wellbeing (89.0 %) in the years preceding death. Whilst confirming other population-level analyses which support terminal decline and drop hypotheses in both mental health and wellbeing, we subsequently identified that most of this effect is driven by a small, but significant minority of the population. Instead, most individuals report stable levels of mental health and wellbeing in the years preceding death.

  1. Increased planned delivery contributes to declining rates of pregnancy hypertension in Australia: a population-based record linkage study.

    Science.gov (United States)

    Roberts, Christine L; Algert, Charles S; Morris, Jonathan M; Ford, Jane B

    2015-10-05

    Since the 1990s, pregnancy hypertension rates have declined in some countries, but not all. Increasing rates of early planned delivery (before the due date) have been hypothesised as the reason for the decline. The aim of this study was to explore whether early planned delivery can partly explain the declining pregnancy hypertension rates in Australia. Population-based record linkage study utilising linked birth and hospital records. A cohort of 1,076,122 deliveries in New South Wales, Australia, 2001-2012. Pregnancy hypertension (including gestational hypertension, pre-eclampsia and eclampsia) was the main outcome; pre-eclampsia was a secondary outcome. From 2001 to 2012, pregnancy hypertension rates declined by 22%, from 9.9% to 7.7%, and pre-eclampsia by 27%, from 3.3% to 2.4% (trend prate was predicted to increase to 10.5%. Examination of annual gestational age distributions showed that pregnancy hypertension rates actually declined from 38 weeks gestation and were steepest from 41 weeks; at least 36% of the decrease could be attributed to planned deliveries. The risk factors for pregnancy hypertension were also risk factors for planned delivery. It appears that an unanticipated consequence of increasing early planned deliveries is a decline in the incidence of pregnancy hypertension. Women with risk factors for hypertension were relatively more likely to be selected for early delivery. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  2. Genetic structure of populations of whale sharks among ocean basins and evidence for their historic rise and recent decline

    KAUST Repository

    Vignaud, Thomas M.

    2014-05-01

    This study presents genetic evidence that whale sharks, Rhincodon typus, are comprised of at least two populations that rarely mix and is the first to document a population expansion. Relatively high genetic structure is found when comparing sharks from the Gulf of Mexico with sharks from the Indo-Pacific. If mixing occurs between the Indian and Atlantic Oceans, it is not sufficient to counter genetic drift. This suggests whale sharks are not all part of a single global metapopulation. The significant population expansion we found was indicated by both microsatellite and mitochondrial DNA. The expansion may have happened during the Holocene, when tropical species could expand their range due to sea-level rise, eliminating dispersal barriers and increasing plankton productivity. However, the historic trend of population increase may have reversed recently. Declines in genetic diversity are found for 6 consecutive years at Ningaloo Reef in Australia. The declines in genetic diversity being seen now in Australia may be due to commercial-scale harvesting of whale sharks and collision with boats in past decades in other countries in the Indo-Pacific. The study findings have implications for models of population connectivity for whale sharks and advocate for continued focus on effective protection of the world\\'s largest fish at multiple spatial scales. © 2014 John Wiley & Sons Ltd.

  3. Genetic structure of populations of whale sharks among ocean basins and evidence for their historic rise and recent decline.

    Science.gov (United States)

    Vignaud, Thomas M; Maynard, Jeffrey A; Leblois, Raphael; Meekan, Mark G; Vázquez-Juárez, Ricardo; Ramírez-Macías, Dení; Pierce, Simon J; Rowat, David; Berumen, Michael L; Beeravolu, Champak; Baksay, Sandra; Planes, Serge

    2014-05-01

    This study presents genetic evidence that whale sharks, Rhincodon typus, are comprised of at least two populations that rarely mix and is the first to document a population expansion. Relatively high genetic structure is found when comparing sharks from the Gulf of Mexico with sharks from the Indo-Pacific. If mixing occurs between the Indian and Atlantic Oceans, it is not sufficient to counter genetic drift. This suggests whale sharks are not all part of a single global metapopulation. The significant population expansion we found was indicated by both microsatellite and mitochondrial DNA. The expansion may have happened during the Holocene, when tropical species could expand their range due to sea-level rise, eliminating dispersal barriers and increasing plankton productivity. However, the historic trend of population increase may have reversed recently. Declines in genetic diversity are found for 6 consecutive years at Ningaloo Reef in Australia. The declines in genetic diversity being seen now in Australia may be due to commercial-scale harvesting of whale sharks and collision with boats in past decades in other countries in the Indo-Pacific. The study findings have implications for models of population connectivity for whale sharks and advocate for continued focus on effective protection of the world's largest fish at multiple spatial scales. © 2014 John Wiley & Sons Ltd.

  4. Two-year decline in vision but not hearing is associated with memory decline in very old adults in a population-based sample.

    Science.gov (United States)

    Anstey, K J; Luszcz, M A; Sanchez, L

    2001-01-01

    Recent cross-sectional research in cognitive aging has demonstrated a robust association between visual acuity, auditory thresholds and cognitive performance in old age. However, the nature of the association is still unclear, particularly with respect to whether sensory and cognitive function are causally related. This study aimed to determine whether marked declines in performance on screening measures of either visual acuity or auditory thresholds have an effect on cognitive decline over 2 years. The sample from the Australian Longitudinal Study of Ageing (n = 2,087) were assessed in 1992 and 1994 on measures of sensory and cognitive function as part of a larger clinical assessment. A quasi-experimental design involving comparison of extreme groups using repeated measures MANCOVA with age as a covariate was used. Group performance on measures of hearing, memory, verbal ability and processing speed declined significantly. Decline in visual acuity had a significant effect on memory decline, but not on decline in verbal ability or processing speed. Decline in hearing was not associated with decline in any cognitive domain. The common association between visual acuity, auditory thresholds and cognitive function observed in cross-sectional studies appears to be disassociated in longitudinal studies. Copyright 2001 S. Karger AG, Basel

  5. Genetic consequences of population decline in the Danish population of the little owl (Athene noctua)

    DEFF Research Database (Denmark)

    Pertoldi, Cino; Pellegrino, Irene; Cucco, Maroc

    2012-01-01

    Background: Danish populations of the little owl (Athene noctua) have experienced dramaticdeclines in size over the past century. Before 1960 the little owl population was abundantin Denmark (estimated N>2000), but between 1960 and 1980 the population declinedrapidly, and since 1980 the little ow...

  6. Ginkgo Biloba Extract and Long-Term Cognitive Decline: A 20-Year Follow-Up Population-Based Study

    Science.gov (United States)

    Amieva, Hélène; Meillon, Céline; Helmer, Catherine; Barberger-Gateau, Pascale; Dartigues, Jean François

    2013-01-01

    Background Numerous studies have looked at the potential benefits of various nootropic drugs such as Ginkgo biloba extract (EGb761®; Tanakan®) and piracetam (Nootropyl®) on age-related cognitive decline often leading to inconclusive results due to small sample sizes or insufficient follow-up duration. The present study assesses the association between intake of EGb761® and cognitive function of elderly adults over a 20-year period. Methods and Findings The data were gathered from the prospective community-based cohort study ‘Paquid’. Within the study sample of 3612 non-demented participants aged 65 and over at baseline, three groups were compared: 589 subjects reporting use of EGb761® at at least one of the ten assessment visits, 149 subjects reporting use of piracetam at one of the assessment visits and 2874 subjects not reporting use of either EGb761® or piracetam. Decline on MMSE, verbal fluency and visual memory over the 20-year follow-up was analysed with a multivariate mixed linear effects model. A significant difference in MMSE decline over the 20-year follow-up was observed in the EGb761® and piracetam treatment groups compared to the ‘neither treatment’ group. These effects were in opposite directions: the EGb761® group declined less rapidly than the ‘neither treatment’ group, whereas the piracetam group declined more rapidly (β = −0.6). Regarding verbal fluency and visual memory, no difference was observed between the EGb761® group and the ‘neither treatment’ group (respectively, β = 0.21 and β = −0.03), whereas the piracetam group declined more rapidly (respectively, β = −1.40 and β = −0.44). When comparing the EGb761® and piracetam groups directly, a different decline was observed for the three tests (respectively β = −1.07, β = −1.61 and β = −0.41). Conclusion Cognitive decline in a non-demented elderly population was lower in subjects who reported using EGb761® than in

  7. Ginkgo biloba extract and long-term cognitive decline: a 20-year follow-up population-based study.

    Directory of Open Access Journals (Sweden)

    Hélène Amieva

    Full Text Available Numerous studies have looked at the potential benefits of various nootropic drugs such as Ginkgo biloba extract (EGb761®; Tanakan® and piracetam (Nootropyl® on age-related cognitive decline often leading to inconclusive results due to small sample sizes or insufficient follow-up duration. The present study assesses the association between intake of EGb761® and cognitive function of elderly adults over a 20-year period.The data were gathered from the prospective community-based cohort study 'Paquid'. Within the study sample of 3612 non-demented participants aged 65 and over at baseline, three groups were compared: 589 subjects reporting use of EGb761® at at least one of the ten assessment visits, 149 subjects reporting use of piracetam at one of the assessment visits and 2874 subjects not reporting use of either EGb761® or piracetam. Decline on MMSE, verbal fluency and visual memory over the 20-year follow-up was analysed with a multivariate mixed linear effects model. A significant difference in MMSE decline over the 20-year follow-up was observed in the EGb761® and piracetam treatment groups compared to the 'neither treatment' group. These effects were in opposite directions: the EGb761® group declined less rapidly than the 'neither treatment' group, whereas the piracetam group declined more rapidly (β = -0.6. Regarding verbal fluency and visual memory, no difference was observed between the EGb761® group and the 'neither treatment' group (respectively, β = 0.21 and β = -0.03, whereas the piracetam group declined more rapidly (respectively, β = -1.40 and β = -0.44. When comparing the EGb761® and piracetam groups directly, a different decline was observed for the three tests (respectively β = -1.07, β = -1.61 and β = -0.41.Cognitive decline in a non-demented elderly population was lower in subjects who reported using EGb761® than in those who did not. This effect may be a specific medication

  8. Ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach.

    Science.gov (United States)

    Christianson, David; Creel, Scott

    2014-01-01

    The reintroduction of wolves (Canis lupus) to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk--Cervus elaphus) in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects of wolves on elk recruitment and population dynamics. Recruitment, as measured by the midwinter juvenile∶female ratio, was a strong determinant of elk dynamics, and declined by 35% in elk herds colonized by wolves as annual population growth shifted from increasing to decreasing. Negative effects of population density and winter severity on recruitment, long recognized as important for elk dynamics, were detected in uncolonized elk herds and in wolf-colonized elk herds prior to wolf colonization, but not after wolf colonization. Growing season precipitation and harvest had no detectable effect on recruitment in either wolf treatment or colonization period, although harvest rates of juveniles∶females declined by 37% in wolf-colonized herds. Even if it is assumed that mortality due to predation is completely additive, liberal estimates of wolf predation rates on juvenile elk could explain no more than 52% of the total decline in juvenile∶female ratios in wolf-colonized herds, after accounting for the effects of other limiting factors. Collectively, these long-term, large-scale patterns align well with prior studies that have reported substantial decrease in elk numbers immediately after wolf recolonization, relatively weak additive effects of direct wolf predation on elk survival, and decreased reproduction and recruitment with exposure to predation risk from wolves.

  9. Ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach.

    Directory of Open Access Journals (Sweden)

    David Christianson

    Full Text Available The reintroduction of wolves (Canis lupus to Yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk--Cervus elaphus in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. Here, we examined data from 33 years for 12 elk population segments spread across southwestern Montana and northwestern Wyoming in a large scale before-after-control-impact analysis of the effects of wolves on elk recruitment and population dynamics. Recruitment, as measured by the midwinter juvenile∶female ratio, was a strong determinant of elk dynamics, and declined by 35% in elk herds colonized by wolves as annual population growth shifted from increasing to decreasing. Negative effects of population density and winter severity on recruitment, long recognized as important for elk dynamics, were detected in uncolonized elk herds and in wolf-colonized elk herds prior to wolf colonization, but not after wolf colonization. Growing season precipitation and harvest had no detectable effect on recruitment in either wolf treatment or colonization period, although harvest rates of juveniles∶females declined by 37% in wolf-colonized herds. Even if it is assumed that mortality due to predation is completely additive, liberal estimates of wolf predation rates on juvenile elk could explain no more than 52% of the total decline in juvenile∶female ratios in wolf-colonized herds, after accounting for the effects of other limiting factors. Collectively, these long-term, large-scale patterns align well with prior studies that have reported substantial decrease in elk numbers immediately after wolf recolonization, relatively weak additive effects of direct wolf predation on elk survival, and decreased reproduction and recruitment with exposure to predation risk from wolves.

  10. Decline of heterozygosity in a large but isolated population: a 45-year examination of moose genetic diversity on Isle Royale

    Directory of Open Access Journals (Sweden)

    Renae L. Sattler

    2017-07-01

    Full Text Available Wildlife conservation and management approaches typically focus on demographic measurements to assess population viability over both short and long periods. However, genetic diversity is an important predictor of long term population vitality. We investigated the pattern of change in genetic diversity in a large and likely isolated moose (Alces alces population on Isle Royale (Lake Superior from 1960–2005. We characterized samples, partitioned into five different 5-year periods, using nine microsatellite loci and a portion of the mtDNA control region. We also simulated the moose population to generate a theoretical backdrop of genetic diversity change. In the empirical data, we found that the number of alleles was consistently low and that observed heterozygosity notably declined from 1960 to 2005 (p = 0.08, R2 = 0.70. Furthermore, inbreeding coefficients approximately doubled from 0.08 in 1960–65 to 0.16 in 2000–05. Finally, we found that the empirical rate of observed heterozygosity decline was faster than the rate of observed heterozygosity loss in our simulations. Combined, these data suggest that genetic drift and inbreeding occurred in the Isle Royale moose populations over the study period, leading to significant losses in heterozygosity. Although inbreeding can be mitigated by migration, we found no evidence to support the occurrence of recent migrants into the population using analysis of our mtDNA haplotypes nor microsatellite data. Therefore, the Isle Royale moose population illustrates that even large populations are subjected to inbreeding in the absence of migration.

  11. The Moon In The Classic Maya World

    Science.gov (United States)

    Romano, Giuliano

    During the Classic Period of the Maya civilization (250-900 A.D.) we have many documents in which it is possible to see the interest of this people on the principal lunar phenomena as the phases and the eclipses in particular. On a number of stelae, lintels and many other inscriptions (in Copan, Quirigua, Tikal, etc.), we can see that in correspondence of the dedication date of the monument, the Maya point out the phase of the Moon and its position in a period of six months corresponding to half year of eclipse. In some parts of the Dresda Codex (one of the four original codices of the Maya) we can see some pages in which were indicated the days of the Tzolkin calendar (the religious calendar of 260 days) in which it is possible to observe a lunar or solar eclipse. The periods of 177 or 148 days are allotted in a sequence that corresponds to the exact interval between the eclipses. The accuracy in the observations and in the calculations of the phases of the Moon, also in very old epochs, is an interesting evidence of the fundamental importance of the Moon in the Maya civilisation.

  12. Egyptians, Maya, Minoans. Learning Works Enrichment Series.

    Science.gov (United States)

    Matthies, Susanna

    The activities in this instructional resource book are designed to be used by gifted 4-8th grade students as independent research guides or in guided or cooperative learning environments. The activities are organized in three sections which focus the ancient civilizations of Egypt, Maya, and Minoa. The activities presented encourage development of…

  13. Does the Maya Forest Need More Roads?

    DEFF Research Database (Denmark)

    Conde, Dalia Amor; Ramos, Victor Hugo; Burgués, Irene

    levels of poverty found in this area. But more and better roads usually bring more people and expand farms. Decision-makers are therefore confronted with a seeming conflict between conservation and development goals. Would new roads be bad or good for the Maya Forest region? To help answer that question...

  14. Perspectives on Ancient Maya Rural Complexity

    OpenAIRE

    Iannone, Gyles; Connell, Samuel V

    2003-01-01

    Settlement archaeology in the Maya area has focused much of its attention on the polar extremes of the settlement continuum. As a result of this urban/rural bias, a whole range of complex rural settlements remain under-explored. The chapters in this volume highlight the variable quality of these "middle level settlements".

  15. Personhood in Maya Art : a theoretical perspective

    NARCIS (Netherlands)

    Osorio, Laura Ann

    2015-01-01

    In contrast to a traditional ethno-archaeological approach, in which contemporary communities are mined for information that can be applied to the past, this study considers that the interpretation of Maya material culture belongs to the people whose identity has been formed within the natural and

  16. Climate Warming as a Possible Trigger of Keystone Mussel Population Decline in Oligotrophic Rivers at the Continental Scale.

    Science.gov (United States)

    Bolotov, Ivan N; Makhrov, Alexander A; Gofarov, Mikhail Yu; Aksenova, Olga V; Aspholm, Paul E; Bespalaya, Yulia V; Kabakov, Mikhail B; Kolosova, Yulia S; Kondakov, Alexander V; Ofenböck, Thomas; Ostrovsky, Andrew N; Popov, Igor Yu; von Proschwitz, Ted; Rudzīte, Mudīte; Rudzītis, Māris; Sokolova, Svetlana E; Valovirta, Ilmari; Vikhrev, Ilya V; Vinarski, Maxim V; Zotin, Alexey A

    2018-01-08

    The effects of climate change on oligotrophic rivers and their communities are almost unknown, albeit these ecosystems are the primary habitat of the critically endangered freshwater pearl mussel and its host fishes, salmonids. The distribution and abundance of pearl mussels have drastically decreased throughout Europe over the last century, particularly within the southern part of the range, but causes of this wide-scale extinction process are unclear. Here we estimate the effects of climate change on pearl mussels based on historical and recent samples from 50 rivers and 6 countries across Europe. We found that the shell convexity may be considered an indicator of the thermal effects on pearl mussel populations under warming climate because it reflects shifts in summer temperatures and is significantly different in viable and declining populations. Spatial and temporal modeling of the relationship between shell convexity and population status show that global climate change could have accelerated the population decline of pearl mussels over the last 100 years through rapidly decreasing suitable distribution areas. Simulation predicts future warming-induced range reduction, particularly in southern regions. These results highlight the importance of large-scale studies of keystone species, which can underscore the hidden effects of climate warming on freshwater ecosystems.

  17. Decreasing systolic blood pressure and declining mortality rates in an untreated population

    DEFF Research Database (Denmark)

    Andersen, Ulla O; Marott, Jacob L; Jensen, Gorm B

    2011-01-01

    The aim of the present study was to evaluate developments in 30 years mortality risk that may be associated with developments in population systolic blood pressure (SBP) and to evaluate possible secular trends in BP-associated mortality risk in the untreated population....

  18. Declining human population but increasing residential development around protected areas in Puerto Rico

    Science.gov (United States)

    J. Castro-Prieto; S. Martinuzzi; V.C. Radeloff; D.P. Helmers; M. Quiñones; W.A. Gould

    2017-01-01

    Increasing residential development around protected areas is a major threat for protected areas worldwide, and human population growth is often the most important cause. However, population is decreasing in many regions as a result of socio-economic changes, and it is unclear how residential development around protected areas is affected in these situations. We...

  19. Trap-induced mass declines in small mammals: Mass as a population index

    Science.gov (United States)

    Dean E. Pearson; Yvette K. Ortega; Leonard F. Ruggiero

    2003-01-01

    Body mass is routinely used as an index of physical condition for comparing small-mammal populations. However, trapping effects on animals may undermine the effectiveness of body mass as an index of population health. We examined the effects of live-trapping on body mass of 3 small-mammal species: deer mice (Peromyscus maniculatus), southern red-...

  20. Personality-Related Determinants of Subtle Cognitive Decline in Old Age: A Population-Based Study

    Directory of Open Access Journals (Sweden)

    Cristelle Rodriguez

    2016-04-01

    Full Text Available Background/Aims: Recent studies of cases with mild cognitive impairment (MCI suggested that besides Alzheimer disease (AD-related biomarkers, some personality dimensions are associated with progression to AD. To date, there are no studies addressing the psychological determinants of subtle cognitive decline in healthy elderly controls. Methods: 488 community-dwelling healthy controls were assessed with a detailed neuropsychological battery at baseline and an 18-month follow-up. Personality factors and facets were investigated at baseline using the NEO-Personality Inventory-Revised (NEO-PI-R. Upon follow-up, there were 264 stable controls (sCON and 224 deteriorating controls (dCON. Their personality data were compared to those of the 102 MCI cases using one-way analysis of variance and logistic regression models. Results: Significantly higher scores of Openness factor (as well as Aesthetics, Ideas and Values facets were found in sCON than in both dCON and MCI cases. The three groups did not differ in the other NEO-PI-R factor and facet scores. Openess factor (and the same facets was associated with cognitive preservation in healthy controls (OR: 0.72, 95% CI: 0.59, 0.87. Lower scores in the same factor and facets conferred higher risk to have MCI (OR: 0.61, 95% CI: 0.46, 0.79. Conclusion: Higher openness to new experiences and thoughts may be a protective factor against early cognitive decline in brain aging.

  1. Browsing Patterns of White-Tailed Deer Following Increased Timber Harvest and a Decline in Population Density

    Directory of Open Access Journals (Sweden)

    Shawn M. Crimmins

    2010-01-01

    Full Text Available We examined browsing patterns of white-tailed deer (Odocoileus virginianus on a site in the central Appalachians that experienced a substantial (>50% reduction in deer population density and an increase in the amount of timber harvest since 2001. We sampled woody browse in and immediately adjacent to 12 clearcuts ranging in age from 0–5 years postharvest in summer 2007. Clearcut-interior areas had higher woody browse abundance and browsing rates than clearcut-edge or mature forest areas. Woody browse abundance was slightly higher within individual clearcuts than in 2001 at higher population densities and lower timber harvest rates. Overall browsing rates declined from approximately 17% in 2001 to less than 5% during our study, suggesting that the combination of deer population control, and increasing the amount of timber harvest across the landscape can reduce herbivory to levels that may not impede growth and survival of forest vegetation.

  2. Genetic footprint of population fragmentation and contemporaneous decline in the endangered Yangtze finless porpoise

    NARCIS (Netherlands)

    Chen, Minmin; Fontaine, Michael C; Chehida, Yacine Ben; Zheng, Jinsong; Labbé, Frédéric; Mei, Zhigang; Hao, Yujiang; Wang, Kexiong; Wu, Min; Zhao, Qingzhong; Wang, Ding

    2017-01-01

    Understanding demographic trends and patterns of gene flow in an endangered species is crucial for devising conservation strategies. Here, we examined the extent of population structure and recent evolution of the critically endangered Yangtze finless porpoise (Neophocaena asiaeorientalis

  3. Population decline of the Elfin-woods Warbler Setophaga angelae in eastern Puerto Rico

    Science.gov (United States)

    W.J. Arendt; S.S. Qian; K. Mineard

    2013-01-01

    We estimated the population density of the globally threatened Elfin-woods Warbler Setophaga angelae within two forest types at different elevations in the Luquillo Experimental Forest in north-eastern Puerto Rico. Population densities ranged from 0.01 to 0.02 individuals/ha in elfin woodland and 0.06–0.26 individuals/ha in palo colorado forest in 2006, with average...

  4. Chronic lack of breeding by Galápagos Blue-footed Boobies and associated population decline

    Directory of Open Access Journals (Sweden)

    David Anchundia

    2014-06-01

    Full Text Available A survey of Blue-footed Boobies (Sula nebouxii excisa throughout the taxon's range in Galápagos, Ecuador found ~6400 adults, compared to a rough estimate of 20,000 in the 1960s. Few pairs bred in 2011-2013 and almost no birds in juvenile plumage were seen. Long-term data suggest that poor breeding began in 1998. Lack of recruitment over this period would mean that the current population is mostly elderly and experiencing senescent decline in performance. Anthropogenic effects such as introduced predators are unlikely to explain this decline because islands with and without such factors exhibited the same low breeding. The poor reproduction seems to be linked to diet. Previous work indicated that sardine and herring (Clupeidae supported successful breeding, but these fish were mostly absent from the diet during this study, except in the central part of Galápagos, where most breeding attempts during this study occurred. Elsewhere in the eastern Pacific sardine abundance has decreased dramatically by natural processes in the last 15 years, as part of a well-documented and apparently natural cycle. This cyclic change in abundance provides a possible explanation for the recent demographic changes in Blue-footed Boobies in Galápagos. Whether natural or anthropogenic in origin, the implications of senescent decline in breeding ability and survival are dramatic for this genetically distinct icon of biodiversity and ecotourism.

  5. Patterns of growth and body condition in sea otters from the Aleutian archipelago before and after the recent population decline

    Science.gov (United States)

    Laidre, K.L.; Estes, J.A.; Tinker, M.T.; Bodkin, James L.; Monson, Daniel H.; Schneider, K.

    2006-01-01

    1. Growth models for body mass and length were fitted to data collected from 1842 sea otters Enhydra lutris shot or live-captured throughout south-west Alaska between 1967 and 2004. Growth curves were constructed for each of two main year groups: 1967–71 when the population was at or near carrying capacity and 1992–97 when the population was in steep decline. Analyses of data collected from animals caught during 2004, when the population density was very low, were precluded by a small sample size and consequently only examined incidentally to the main growth curves.2. Growth curves demonstrated a significant increase in body mass and body length at age in the 1990s. Asymptotic values of body mass were 12–18% higher in the 1990s than in the 1960s/70s, and asymptotic values for body length were 10–11% higher between the same periods. Data collected in 2004 suggest a continued increase in body size, with nearly all data points for mass and length falling significantly above the 1990s growth curves.3. In addition to larger asymptotic values for mass and length, the rate of growth towards asymptotic values was more rapid in the 1990s than in the 1960s/70s: sea otters reached 95% of asymptotic body mass and body length 1–2 years earlier in the 1990s.4. Body condition (as measured by the log mass/log length ratio) was significantly greater in males than in females. There was also an increasing trend from the 1960s/70s through 2004 despite much year-to-year variation.5. Population age structures differed significantly between the 1960s/70s and the 1990s with the latter distribution skewed toward younger age classes (indicating an altered lxfunction) suggesting almost complete relaxation of age-dependent mortality patterns (i.e. those typical of food-limited populations).6. This study spanned a period of time over which the population status of sea otters in the Aleutian archipelago declined precipitously from levels at or near equilibrium densities at

  6. A water storage adaptation in the maya lowlands.

    Science.gov (United States)

    Scarborough, V L; Gallopin, G G

    1991-02-08

    Prehispanic water management in the Maya Lowlands emphasized collection and storage rather than the canalization and diversion accentuated in highland Mexico. Reexamination of site maps of the ancient Maya city of Tikal, Guatemala, has revealed an important, overlooked factor in Maya centralization and urban settlement organization. In a geographical zone affected by an extended dry season and away from permanent water sources, large, well-planned reservoirs provided resource control as well as political leverage.

  7. Collapse, conquest and Maya survival at Lamanai, Belize

    Directory of Open Access Journals (Sweden)

    Elizabeth Graham

    2000-11-01

    Full Text Available The Maya civilization of Central America prompts visions of mysterious stone temples now buried in tropical forest. It is commonly supposed to have collapsed suddenly in the ninth century AD, but some Maya settlements, such as Lamanai, survived into the colonial period. Here a new member of the Institute's academic staff gives a personal account of how working in Belize transformed her understanding of Maya civilization and its aftermath.

  8. Collapse, conquest and Maya survival at Lamanai, Belize

    OpenAIRE

    Graham, Elizabeth

    2000-01-01

    The Maya civilization of Central America prompts visions of mysterious stone temples now buried in tropical forest. It is commonly supposed to have collapsed suddenly in the ninth century AD, but some Maya settlements, such as Lamanai, survived into the colonial period. Here a new member of the Institute's academic staff gives a personal account of how working in Belize transformed her understanding of Maya civilization and its aftermath.

  9. Diclofenac disposition in Indian cow and goat with reference to Gyps vulture population declines

    Energy Technology Data Exchange (ETDEWEB)

    Taggart, M.A. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire, SG19 2DL (United Kingdom); School of Biological Sciences, Department of Plant and Soil Science, University of Aberdeen, AB24 3UU (United Kingdom); Cuthbert, R. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire, SG19 2DL (United Kingdom)]. E-mail: richard.cuthbert@rspb.org.uk; Das, D. [Bombay Natural History Society, Hornbill House, Mumbai, 400023 (India); Sashikumar, C. [Bombay Natural History Society, Hornbill House, Mumbai, 400023 (India); Pain, D.J. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire, SG19 2DL (United Kingdom); Green, R.E. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire, SG19 2DL (United Kingdom); Conservation Biology Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ (United Kingdom); Feltrer, Y. [Institute of Zoology, Zoological Society of London, Regent' s Park, London, NW1 4RY (United Kingdom); Shultz, S. [Royal Society for the Protection of Birds, The Lodge, Sandy, Bedfordshire, SG19 2DL (United Kingdom); Institute of Zoology, Zoological Society of London, Regent' s Park, London, NW1 4RY (United Kingdom); Cunningham, A.A. [Institute of Zoology, Zoological Society of London, Regent' s Park, London, NW1 4RY (United Kingdom); Meharg, A.A. [School of Biological Sciences, Department of Plant and Soil Science, University of Aberdeen, AB24 3UU (United Kingdom)

    2007-05-15

    Gyps vultures across India are declining rapidly and the NSAID diclofenac has been shown to be the major cause. Vultures scavenge livestock carcasses that have been treated with diclofenac within the days preceding death. We present data on diclofenac disposition in Indian cow and goat, and field data on the prevalence of diclofenac in carcases in the environment. In the disposition experiment, animals were treated with a single intramuscular injection of diclofenac at 1000 {mu}g kg{sup -1} bw. In cow, diclofenac was detectable in liver, kidney and intestine up to 71 h post-treatment; in plasma, half-life was 12.2 h. In goat, tissue residues were undetectable after 26 h. Prevalence of diclofenac in liver from 36 dead livestock collected in the field was 13.9%. Data suggest that diclofenac residues in Indian cow and goat are short-lived, but diclofenac prevalence in carcasses available to vultures may still be very high. - Residual diclofenac in livestock carcasses in India poses a continuing risk to Gyps vultures.

  10. Diclofenac disposition in Indian cow and goat with reference to Gyps vulture population declines

    International Nuclear Information System (INIS)

    Taggart, M.A.; Cuthbert, R.; Das, D.; Sashikumar, C.; Pain, D.J.; Green, R.E.; Feltrer, Y.; Shultz, S.; Cunningham, A.A.; Meharg, A.A.

    2007-01-01

    Gyps vultures across India are declining rapidly and the NSAID diclofenac has been shown to be the major cause. Vultures scavenge livestock carcasses that have been treated with diclofenac within the days preceding death. We present data on diclofenac disposition in Indian cow and goat, and field data on the prevalence of diclofenac in carcases in the environment. In the disposition experiment, animals were treated with a single intramuscular injection of diclofenac at 1000 μg kg -1 bw. In cow, diclofenac was detectable in liver, kidney and intestine up to 71 h post-treatment; in plasma, half-life was 12.2 h. In goat, tissue residues were undetectable after 26 h. Prevalence of diclofenac in liver from 36 dead livestock collected in the field was 13.9%. Data suggest that diclofenac residues in Indian cow and goat are short-lived, but diclofenac prevalence in carcasses available to vultures may still be very high. - Residual diclofenac in livestock carcasses in India poses a continuing risk to Gyps vultures

  11. Declines in populations of Salix caprea L.during forest regeneration after strong herbivore pressure

    Directory of Open Access Journals (Sweden)

    Janusz B. Faliński

    2014-01-01

    Full Text Available Communities of broadleaved forest subject to strong pressure from large herbivores underwent degeneration. The relief of this pressure led to regeneration of the community, in which an important role was played by the sallow Salix caprea and other light-seeded pioneer species of tree (Populus tremula, Betula pendula and B. pubescens. Regeneration involving Salix caprea proceeded following the conservatorial protection of the degenerate stands in a reserve and later in Białowieża National Park. The emergence and development of the population of Salix caprea proceeded following the invasion of spruce, which coincided with the period of enhanced animal pressure on broadleaved forest. Salix caprea filled all the gaps in the tree stand arising as a result of the destruction of trees and undergrowth by herbivores (in the years 1892-1915. It also appeared en masse on old, at that time unforested, clearings and felled areas. In these places, Salix caprea created very abundant populations, with particular trees being in good condition, with a habit typical of forest trees and attaining considerable heights. The majority of trees were 50-60 years old at the time of death, although individuals reached 74 years of age. The process of extinction of the sallow population - observed over 19 years on permanent plots and fixed trees - proceeded very quickly, especially in the first decade of observation. It led to the almost complete disappearance of sallow for the forest communities of Białowieża National Park. The death of individual trees is preceded by impairment of their health and reduced annual increments in the 4-9 last years of life. The extinction of the population is associated with the loss of its primary phenological differentiation and with a change in the sex structure of the population from a prevalence of female trees to a near even distribution of the two sexes. The development of the populations of permanent constituents of the forest

  12. Genetic consequences of population decline in Eurasian otter (Lutra lutra) populations in the Czech and Slovak Republics

    Czech Academy of Sciences Publication Activity Database

    Gettová, Lenka; Hájková, Petra

    Supp., - (2011), s. 102 ISSN 0394-1914. [International Otter Colloquium /11./. 30.08.2011-04.09.2011, Pavia] R&D Projects: GA AV ČR KJB600930804 Institutional research plan: CEZ:AV0Z60930519 Keywords : Eurasian otter * population size Subject RIV: EG - Zoology http://www.internationalottercolloquium2010.eu/files/proceedings_iucn_xi_ioc_2011.pdf

  13. Measuring progress towards achieving Millennium Development Goals in small populations: is under-five mortality in Tuvalu declining?

    Science.gov (United States)

    Taylor, Richard; Linhart, Christine; Hayes, Geoffrey; Homasi, Steven

    2014-08-01

    Infant mortality rates (IMR) and under-five mortality rates (U5MR) in Tuvalu (2010 population 11,149) for 1990-2011 were evaluated to determine best estimates of levels and trends. Estimates were graphed over time to identify trends/inconsistencies, and censored for reliability/plausibility. Where possible, 95% confidence intervals (CIs) and tests for linear trend were calculated. Ministry of Health (MoH) data indicates IMR and U5MR (per 1,000 live births) declined over 1990-2008: IMR 62 (95%CI 46-81) for 1991-93 (51 deaths) to 19 (95%CI 10-33) for 2006-08 (12 deaths); U5MR 67 (95%CI 50-87) for 1991-93 (55 deaths) to 19 (95%CI 10-33) for 2006-08 (12 deaths). The 2007 Demographic and Health Survey (DHS) suggests recent trends are increasing: IMR 24 for 1998-2002 to 31 (95%CI 20-42) for 2003-07; U5MR 29 for 1998-2002 to 36 (95%CI 30-43) for 2003-07 (deaths not provided). Tests for linear trend and 95%CIs indicate MoH declines are statistically significant, but recent increased estimates from DHS are not, and could be affected by recall bias. Small populations provide challenges in interpretation of IMR/U5MR trends. To ensure the correct interpretation of rates, CIs (95%) and tests for trend should be calculated. Tuvalu has experienced steady decline in IMR/U5MR over the past 20 years. © 2014 Public Health Association of Australia.

  14. Analysis of the Causes of a Decline in the San Joaquin Kit Fox Population on the Elk Hills, Naval Petroleum Reserve #1, California

    Science.gov (United States)

    EPA is announcing the availability of the final report, Analysis of the Causes of a Decline in the San Joaquin Kit Fox Population on the Elk Hills, Naval Petroleum Reserve #1, California. This report describes a causal assessment of the decline in the abundance of San Joaq...

  15. The ongoing decline of the breeding population of Black-tailed Godwits Limosa l. limosa in The Netherlands is not explained by changes in adult survival

    NARCIS (Netherlands)

    Roodbergen, Maja; Klok, Chris; Schekkerman, Hans

    2008-01-01

    The Black-tailed Godwit Limosa limosa is a characteristic breeding wader of wet grasslands in The Netherlands which has suffered a strong population decline since the 1960s. Low breeding success has been implicated as the main driver of this decline and here we examine whether changes in adult

  16. The ongoing decline of the breeding population of Black-tailed Godwits Limosa l. limosa in The Netherlands is not explained by changes in adult survival

    NARCIS (Netherlands)

    Roodbergen, M.; Klok, C.; Schekkerman, H.

    2008-01-01

    The Black-tailed Godwit Limosa limosa is a characteristic breeding wader of wet grasslands in the Netherlands which has suffered a strong population decline since the 1960s. Low breeding success has been implicated as the main driver of this decline and here we examine whether changes in adult

  17. Stars Influence on the Earth in Maya Culture: Stars and Planets in Maya Culture

    Directory of Open Access Journals (Sweden)

    Emanuel George Oprea

    2015-11-01

    Full Text Available The Mesoamerican Culture of Maya’s was one of the ancient and advanced cultures of the American continent and they influenced other Amerindian peoples. The life of Maya people, of the Earth itself and of the Universe is set and constructed around Maya Calendar and has a cyclic character as a direct influence of the stars. Many centuries the Western civilization with the its linear Calendar had not accepted the ideas of the possible influence of the stars and planets to peoples lives. The end of the last century and the beginning of XXI’s had started to demonstrate the opposite. The present work tries to show the process of meeting and intersection of the ancient ideas of Maya civilization and some of new ideas from the modern sciences.

  18. Can Citizen Science Assist in Determining Koala (Phascolarctos cinereus) Presence in a Declining Population?

    Science.gov (United States)

    Flower, Emily; Jones, Darryl; Bernede, Lilia

    2016-07-14

    The acceptance and application of citizen science has risen over the last 10 years, with this rise likely attributed to an increase in public awareness surrounding anthropogenic impacts affecting urban ecosystems. Citizen science projects have the potential to expand upon data collected by specialist researchers as they are able to gain access to previously unattainable information, consequently increasing the likelihood of an effective management program. The primary objective of this research was to develop guidelines for a successful regional-scale citizen science project following a critical analysis of 12 existing citizen science case studies. Secondly, the effectiveness of these guidelines was measured through the implementation of a citizen science project, Koala Quest, for the purpose of estimating the presence of koalas in a fragmented landscape. Consequently, this research aimed to determine whether citizen-collected data can augment traditional science research methods, by comparing and contrasting the abundance of koala sightings gathered by citizen scientists and professional researchers. Based upon the guidelines developed, Koala Quest methodologies were designed, the study conducted, and the efficacy of the project assessed. To combat the high variability of estimated koala populations due to differences in counting techniques, a national monitoring and evaluation program is required, in addition to a standardised method for conducting koala population estimates. Citizen science is a useful method for monitoring animals such as the koala, which are sparsely distributed throughout a vast geographical area, as the large numbers of volunteers recruited by a citizen science project are capable of monitoring a similarly broad spatial range.

  19. Predicting the effects of copper on local population decline of 2 marine organisms, cobia fish and whiteleg shrimp, based on avoidance response.

    Science.gov (United States)

    Araújo, Cristiano V M; Cedeño-Macías, Luís A; Vera-Vera, Victoria C; Salvatierra, David; Rodríguez, Elizabeth N V; Zambrano, Ufredo; Kuri, Samir

    2016-02-01

    The present study focuses on avoidance response to predict population decline of the marine fish Rachycentron canadum (cobia) and larvae of the estuarine shrimp Litopenaeus vannamei (whiteleg shrimp). Avoidance of approximately 60% was recorded for the cobia fry exposed to 1.0 mg Cu/L, 1.60 mg Cu/L, and 1.80 mg Cu/L. For the shrimp larvae, avoidance was approximately 80% for all Cu concentrations. The population decline of cobia fry was conditioned by avoidance in lower concentrations. However, in higher concentrations mortality begins to play an important role. The displacement toward uncontaminated habitats might determine shrimp population decline. A Cu-contaminated environment can determine the habitat selection of both species and, therefore, their local population decline. © 2015 SETAC.

  20. Reproductive characteristics and population decline of four species of skate (Rajidae) off the eastern coast of Canada.

    Science.gov (United States)

    Mcphie, R P; Campana, S E

    2009-07-01

    Four of the most common species of skate (Rajidae) were studied off eastern Canada to determine if their reproductive characteristics were linked to their population trajectories. The fecundity of the winter skate Leucoraja ocellata, the little skate Leucoraja erinacea, the thorny skate Amblyraja radiata and the smooth skate Malacoraja senta averaged between 41 and 56 egg cases per year for each species. For all species but L. ocellata, males matured at larger sizes and at later ages than females. Theoretical rates of population increase for non-equilibrium populations of L. ocellata (c. 0.07), M. senta (c. 0.14) and L. erinacea and A. radiata (c. 0.20) were low compared to most fishes, indicating that north-west Atlantic skates are intrinsically unproductive, yet are theoretically capable of supporting low-level fisheries. Nevertheless, the results of 36 years of research surveys indicate that the abundance of mature L. ocellata, A. radiata and M. senta all decreased by >90% since 1970, indicating that past fishing mortality (both directed and undirected) has outstripped the net productivity of the skate populations on the eastern Scotian Shelf. The relationship between maximum age (t(max)) and age of maturity (t(mat)) was a better predictor of population growth rate than was body size, with the species exhibiting the highest ratios of t(mat) :t(max) (L. ocellata = 0.68, M. senta = 0.66) having the lowest predicted population growth rates. L. ocellata appears to have the lowest productivity and has experienced the greatest population decline, thus raising concerns over its future status.

  1. Spatial and temporal variation in population dynamics of Andean frogs: Effects of forest disturbance and evidence for declines

    Directory of Open Access Journals (Sweden)

    Esther M. Cole

    2014-08-01

    Full Text Available Biodiversity loss is a global phenomenon that can result in the collapse of food webs and critical ecosystem services. Amphibian population decline over the last century is a notable case of species loss because amphibians survived the last four major extinction events in global history, their current rate of extinction is unprecedented, and their rate of extinction is greater than that for most other taxonomic groups. Despite the severity of this conservation problem and its relevance to the study of global biodiversity loss, major knowledge gaps remain for many of the most threatened species and regions in the world. Rigorous estimates of population parameters are lacking for many amphibian species in the Neotropics. The goal of our study was to determine how the demography of seven species of the genus Pristimantis varied over time and space in two cloud forests in the Ecuadorian Andes. We completed a long term capture–mark–recapture study to estimate abundance, survival, and population growth rates in two cloud forests in the Ecuadorian Andes; from 2002 to 2009 at Yanayacu in the Eastern Cordillera and from 2002 to 2003 at Cashca Totoras in the Western Cordillera. Our results showed seasonal and annual variation in population parameters by species and sex. P. bicantus experienced significant reductions in abundance over the course of our study. Abundance, apparent survival, and population growth rates were lower in disturbed than in primary or mature secondary forest. The results of our study raise concerns for the population status of understudied amphibian groups and provide insights into the population dynamics of Neotropical amphibians.

  2. THE ASSISMENT OF MAYA VERNACULAR HERITAGE FROM UNIVERSE CONCEPT TO POVERTY CONCEPT

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    Aurelio Sánchez

    2014-08-01

    Full Text Available The traditional technique maya housing construction is the representation of the Mayan worldview, it is expressed through the name of each construction element meanings of the creation of the universe and man, is also referred to the body and the concept of a living. For many centuries it was the oral tradition and construction practices that kept this knowledge and knowing, until the process of deterioration with colonialism, the arrival of the Spanish was a watershed in its decline to the undervaluation and contempt. The international designations like vernacular architecture of little have served before the governmental programs that continue it cataloguing like noncompatible an inhabitable space with their criteria of “quality of life”, nor with the schemes of tie financing to industrialized materials. Recent proposals for housing support maya not provide its being as its spatial bioclimatic architecture and a way of life, encouraging new construction beyond its dynamic and undervalued the maya solar microhabitat. Urges a reassessment based on its original conception, in its sustainable architectural feature in your living space according to the social dynamics of its inhabitants and its recognition as a cultural heritage.

  3. VAM populations in relation to grass invasion associated with forest decline.

    Science.gov (United States)

    Vosatka, M; Cudlin, P; Mejstrik, V

    1991-01-01

    Spruce stands in Northern Bohemia forests, damaged to various degrees by industrial pollution, have shown establishment of grass cover following tree defoliation. Populations of vesicular-arbuscular mycorrhizal (VAM) fungi were studied under this grass cover in four permanent plots with spruce under different levels of pollution stress. Soil and root samples were collected in April and June within each plot as follows: (1) sites without grass, (2) sites with initial stages of grass invasion, and (3) sites with fully developed grass cover. In all plots, the highest number of propagules were recovered from samples taken from sites having full grass cover. Mycorrhizal infection of grass was highest in the plot with the severest pollution damage and lowest in the least damaged plot. The development of grass cover and VAM infection of grass increased with tree defoliation caused by air pollution.

  4. Can Citizen Science Assist in Determining Koala (Phascolarctos cinereus Presence in a Declining Population?

    Directory of Open Access Journals (Sweden)

    Emily Flower

    2016-07-01

    Full Text Available The acceptance and application of citizen science has risen over the last 10 years, with this rise likely attributed to an increase in public awareness surrounding anthropogenic impacts affecting urban ecosystems. Citizen science projects have the potential to expand upon data collected by specialist researchers as they are able to gain access to previously unattainable information, consequently increasing the likelihood of an effective management program. The primary objective of this research was to develop guidelines for a successful regional-scale citizen science project following a critical analysis of 12 existing citizen science case studies. Secondly, the effectiveness of these guidelines was measured through the implementation of a citizen science project, Koala Quest, for the purpose of estimating the presence of koalas in a fragmented landscape. Consequently, this research aimed to determine whether citizen-collected data can augment traditional science research methods, by comparing and contrasting the abundance of koala sightings gathered by citizen scientists and professional researchers. Based upon the guidelines developed, Koala Quest methodologies were designed, the study conducted, and the efficacy of the project assessed. To combat the high variability of estimated koala populations due to differences in counting techniques, a national monitoring and evaluation program is required, in addition to a standardised method for conducting koala population estimates. Citizen science is a useful method for monitoring animals such as the koala, which are sparsely distributed throughout a vast geographical area, as the large numbers of volunteers recruited by a citizen science project are capable of monitoring a similarly broad spatial range.

  5. Effects of population based screening for Chlamydia infections in the Netherlands limited by declining participation rates.

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    Boris V Schmid

    Full Text Available BACKGROUND: A large trial to investigate the effectiveness of population based screening for chlamydia infections was conducted in the Netherlands in 2008-2012. The trial was register based and consisted of four rounds of screening of women and men in the age groups 16-29 years in three regions in the Netherlands. Data were collected on participation rates and positivity rates per round. A modeling study was conducted to project screening effects for various screening strategies into the future. METHODS AND FINDINGS: We used a stochastic network simulation model incorporating partnership formation and dissolution, aging and a sexual life course perspective. Trends in baseline rates of chlamydia testing and treatment were used to describe the epidemiological situation before the start of the screening program. Data on participation rates was used to describe screening uptake in rural and urban areas. Simulations were used to project the effectiveness of screening on chlamydia prevalence for a time period of 10 years. In addition, we tested alternative screening strategies, such as including only women, targeting different age groups, and biennial screening. Screening reduced prevalence by about 1% in the first two screening rounds and leveled off after that. Extrapolating observed participation rates into the future indicated very low participation in the long run. Alternative strategies only marginally changed the effectiveness of screening. Higher participation rates as originally foreseen in the program would have succeeded in reducing chlamydia prevalence to very low levels in the long run. CONCLUSIONS: Decreasing participation rates over time profoundly impact the effectiveness of population based screening for chlamydia infections. Using data from several consecutive rounds of screening in a simulation model enabled us to assess the future effectiveness of screening on prevalence. If participation rates cannot be kept at a sufficient level

  6. HIV decline associated with changes in risk behaviours among young key populations in Nepal: analysis of population-based HIV prevalence surveys between 2001 and 2012.

    Science.gov (United States)

    Deuba, Keshab; Ekström, Anna Mia; Tomson, Göran; Shrestha, Rachana; Marrone, Gaetano

    2017-08-01

    We assessed changes in HIV prevalence and risk behaviours among young key populations in Nepal. A total of 7505 participants (aged 16-24 years) from key populations who were at increased risk of HIV infection (2767 people who inject drugs (PWID); 852 men who have sex with men/transgender (MSM/TG); 2851 female sex workers (FSW) and 1035 male labour migrants) were recruited randomly over a 12-year period, 2001-2012. Local epidemic zones of Nepal (Kathmandu valley, Pokhara valley, Terai Highway and West to Far West hills) were analysed separately. We found a very strong and consistent decline in HIV prevalence over the past decade in different epidemic zones among PWID and MSM/TG in Kathmandu, the capital city, most likely due to a parallel increase in safe needle and syringe use and increased condom use. A decrease in HIV prevalence in 22 Terai highway districts, sharing an open border with India, was also consistent with increased condom use among FSW. Among male labour migrants, HIV prevalence was low throughout the period in the West to Far West hilly regions. Condom use by migrant workers involved with FSW abroad increased while their condom use with Nepalese FSW declined. Other risk determinants such as mean age at starting first injection, injection frequency, place of commercial sex solicitation, their mean age when leaving to work abroad did not change consistently across epidemic zones among the young key populations under study. In Nepal, the decline in HIV prevalence over the past decade was remarkably significant and consistent with an increase in condom use and safer use of clean needles and syringes. However, diverging trends in risk behaviours across local epidemic zones of Nepal suggest a varying degree of implementation of national HIV prevention policies. This calls for continued preventive efforts as well as surveillance to sustain the observed downward trend.

  7. Functional decline and nutritional status in a hospitalized geriatric population: sequential study.

    Science.gov (United States)

    Morales-Rodriguez, P; González-Reimers, E; Santolaria-Fernández, F; Batista-López, N; González-Reyes, A

    1990-01-01

    We analyzed the relations between nutritional status and several measures of the ability to perform the normal activities of daily living (ADL) in a long-term institutionalized geriatric population and also studied whether changes in this ability, as found ten months later, were associated with changes in the nutritional status. Nutritional status was assessed using objective anthropometric measurements (triceps skinfold, mid upper-arm circumference, midarm muscle area [AMA], midarm fat area [AFA]) and subjective clinical features (temporal muscle atrophy [TMA] and Bichat's fat atrophy [BFA]). The capacity to perform ADL was analyzed considering ability to eat and to walk, dental status, and mental performance status. Patients with total absence or loss of more than 50% of the teeth showed less AMA and AFA and greater degrees of TMA and BFA; the same happened with regard to deterioration of mental performance status. Those patients fed through a nasogastric tube showed less AFA and serum albumin and also a greater degree of TMA and BFA. Patients unable to walk without aid showed less AMA and AFA. Patients whose capacity to walk improved or whose mental performance status ameliorated showed an increase of their AMA, whereas AFA slightly decreased in those patients whose abilities to eat and to walk deteriorated. Long-term hospitalization in our center led to improvement and to deterioration of ADL in approximately the same number of patients, and similar changes were seen in the nutritional measures.

  8. Overcoming challenges to the recovery of declining amphibian populations in the United States

    Science.gov (United States)

    Walls, Susan; Ball, Lianne C.; Barichivich, William J.; Dodd, Kenneth; Enge, Kevin M; Gorman, Thomas A.; O'Donnell, Katherine; Palis, John G; Semlitsch, Raymond D.

    2016-01-01

    The US Endangered Species Act of 1973 (ESA) affords many potential benefits to species threatened with extinction. However, most at-risk amphibians—one of the most imperiled vertebrate groups—remain unlisted under the provisions of the ESA, and many impediments to recovery exist for those species that have been listed. Of the 35 US amphibian species and distinct population segments (“taxa”) listed under the ESA, 40% currently lack a final (completed) recovery plan, 28.6% lack designated critical habitat, and 8.6% lack both. For taxa that have recovery plans, the time between their listing and the development of those plans was from 2 to 29 years, and the time between their listing and the designation of critical habitat ranged from 0 to 14 years. The underlying causes of such delays in protection are complex and constitute obstacles to recovery of imperiled species. We outline a series of strategic actions by which these challenges may be overcome.

  9. How maya women respond to changing technology : The effect of helping behavior on initiating reproduction.

    Science.gov (United States)

    Kramer, K L; McMillan, G P

    1998-06-01

    In the mid 1970s labor-saving technology was introduced into a Maya subsistence agricultural community that markedly increased the efficiency with which maize could be ground and water collected. This increased efficiency introduces a possible savings in the time that women allocate to work, which can be reapportioned to child care, food production, domestic work, or leisure. An earlier study suggested that this labor-saving technology had a positive effect in decreasing the age at which these Maya women begin their reproductive careers. Although there is a statistical association between the age at which women bear their first child and the introduction of modern technology, this association does not demonstrate that the decline in age at first birth is causally related to the presence of technology. This paper pursues two objectives to evaluate this potential causal relationship in greater detail. First, a theory relating technological change to the initiation of a reproductive career is briefly developed in order to make qualitative predictions about behavioral changes as a response to changing technology. Second, these predictions are then tested against time allocation data recently collected in this same Maya community.We suggest that both of the conditions necessary to initiate reproduction-fecundity and access to mates-fundamentally depend on the amount of help that a girl provides to her family. Further, the help that a girl provides can be affected by technological changes. Analyses show that when modern technology is available, unmarried young women do not change the time allocated to domestic tasks and child care, and allocate more time to low-energy leisure activities. This lack of perceived benefit to working more and a potential concomitant shift towards a positive energy balance may in part explain why Maya women leave home and initiate reproduction at a younger age after labor-saving technology is introduced.

  10. A distribution analysis of the central Maya lowlands ecoinformation network: its rises, falls, and changes

    Directory of Open Access Journals (Sweden)

    Joel D. Gunn

    2017-03-01

    Full Text Available We report a study of central Maya lowland dynastic information networks, i.e., six cities' external elite ceramic influences, and how they reflect the decision-making practices of Maya elites over 3000 years. Forest cover, i.e., Moraceae family pollen, was added to the network analysis to provide ecological boundary conditions, thus ecologically moderated information networks. Principal components analysis revealed three dominant patterns. First, the networking of interior cities into powerful polities in the Late Preclassic and Classic periods (400 BCE-800 CE. In a second pattern, coastal cities emerged as key entrepôts based on marine navigation (Terminal and Postclassic periods, 800-1500 CE. Climate dynamics and sustainability considerations facilitated the transition. Forest cover, a measure of ecosystem health, shows interior forests diminished as interior cities networked but rebounded as their networks declined. By contrast, coastal forests flourished with networks implying that the marine-based economy was sustainable. Third, in the Classic, the network-dominant coast, west or east, changed with interior polities' political struggles, the critical transition occurring after 695 CE as Tikal gained dominance over the Calakmul-Caracol alliance. Beginning with the Late Preclassic about 2000 years ago, it is possible to assign names to the decision makers by referencing the growing literature on written Maya records. Although the detectable decision sequence evident in this analysis is very basic, we believe it does open possible avenues to much deeper understanding as the study proceeds into the future. The Integrated History and Future of People on Earth-Maya working group that sponsored the analysis anticipates that it will provide actionable social science intelligence for future decision making at the global scale.

  11. Founding Amerindian mitochondrial DNA lineages in ancient Maya from Xcaret, Quintana Roo.

    Science.gov (United States)

    González-Oliver, A; Márquez-Morfín, L; Jiménez, J C; Torre-Blanco, A

    2001-11-01

    Ancient DNA from the bone remains of 25 out of 28 pre-Columbian individuals from the Late Classic-Postclassic Maya site of Xcaret, Quintana Roo, was recovered, and mitochondrial DNA (mtDNA) was amplified by using the polymerase chain reaction. The presence of the four founding Amerindian mtDNA lineages was investigated by restriction analysis and by direct sequencing in selected individuals. The mtDNA lineages A, B, and C were found in this population. Eighty-four percent of the individuals were lineage A, whereas lineages B and C were present at low frequencies, 4% and 8%, respectively. Lineage D was absent from our sample. One individual did not possess any of the four lineages. Six skeletons out of 7 dated from the Late Classic period were haplotype A, whereas 11 skeletons out of 16 dated from the Postclassic period were also haplotype A. The distribution of mtDNA lineages in the Xcaret population contrasts sharply with that found in ancient Maya from Copán, which lack lineages A and B. On the other hand, our results resemble more closely the frequencies of mtDNA lineages found in contemporary Maya from the Yucatán Peninsula and in other Native American contemporary populations of Mesoamerican origin. Copyright 2001 Wiley-Liss, Inc.

  12. Future Estimation of Convenience Living Facilities Withdrawal due to Population Decline all Over Japan from 2010 TO 2040 - Focus on Supermarkets, Convenience Stores and Drugstores

    Science.gov (United States)

    Nishimoto, Yuka; Akiyama, Yuki; Shibasaki, Ryosuke

    2016-06-01

    Population explosion is considered to be one of the most crucial problems in the world. However, in Japan, the opposite problem: population decline has become serious now. Japanese population is estimated to decrease by twenty millions in 2040. This negative situation will cause to increase areas where many residents cannot make a daily living all over Japan because many convenience living facilities such as supermarkets, convenience stores and drugstores will be difficult to maintain their market area population due to future population decline. In our research, we used point data of convenience living facilities developed by address geocoding of digital telephone directory and point data of future population projection developed by distribution of Japanese official population projection data proportionally among the building volume of digital residential map, which can monitor building volumes all over Japan. In conclusion, we estimated that various convenience living facilities in Japan will shrink and close by population decline in near future. In particular, it is cleared that approximately 14.7% of supermarkets will be possible to withdraw all over Japan by 2040. In addition, it is cleared that over 40% of supermarkets in some countryside prefectures will be possible to withdraw by 2040. Thus, we estimated future distributions of convenience living facilities that cannot maintain their market area population due to future population decline. Moreover, we estimated the number of people that they will become inconvenience in buying fresh foods.

  13. FUTURE ESTIMATION OF CONVENIENCE LIVING FACILITIES WITHDRAWAL DUE TO POPULATION DECLINE ALL OVER JAPAN FROM 2010 TO 2040 - FOCUS ON SUPERMARKETS, CONVENIENCE STORES AND DRUGSTORES

    Directory of Open Access Journals (Sweden)

    Y. Nishimoto

    2016-06-01

    Full Text Available Population explosion is considered to be one of the most crucial problems in the world. However, in Japan, the opposite problem: population decline has become serious now. Japanese population is estimated to decrease by twenty millions in 2040. This negative situation will cause to increase areas where many residents cannot make a daily living all over Japan because many convenience living facilities such as supermarkets, convenience stores and drugstores will be difficult to maintain their market area population due to future population decline. In our research, we used point data of convenience living facilities developed by address geocoding of digital telephone directory and point data of future population projection developed by distribution of Japanese official population projection data proportionally among the building volume of digital residential map, which can monitor building volumes all over Japan. In conclusion, we estimated that various convenience living facilities in Japan will shrink and close by population decline in near future. In particular, it is cleared that approximately 14.7% of supermarkets will be possible to withdraw all over Japan by 2040. In addition, it is cleared that over 40% of supermarkets in some countryside prefectures will be possible to withdraw by 2040. Thus, we estimated future distributions of convenience living facilities that cannot maintain their market area population due to future population decline. Moreover, we estimated the number of people that they will become inconvenience in buying fresh foods.

  14. The recent decline of Montastraea annularis (complex coral populations in western Curaçao: a cause for concern?

    Directory of Open Access Journals (Sweden)

    A. W Bruckner

    2006-12-01

    Full Text Available Shallow leeward reefs off the western end of Curaçao are dominated by extensive populations of M. annularis (complex. These species are larger in size (mean= 66 cm diameter than all other species, with few small colonies (10 cm observed within transects, and most exhibited low levels of partial mortality (mean= 22.5%. These species were less abundant (38% of all colonies in 2005. Partial mortality among live colonies of M. annularis and M. faveolata increased by 85% (mean = 42% partial mortality and numerous dead colonies of M. faveolata and M. annularis were observed; M. franksi colonies were generally in excellent condition (14% partial tissue mortality. A high prevalence of coral diseases (3-30% was documented among M. annularis and M. faveolata, while all other species were less frequently affected. Yellow band disease (YBD emerged shortly after the 1995 bleaching event, and rapidly spread throughout all depths, with the highest prevalence between 1997-1999. YBD caused slow rates of mortality (=1 cm/month, but multiple focal lesions appeared on individual colonies, and these progressively radiated outward as they killed the colonies. By 2005, 44% of the tagged corals were dead; the remainder exhibited active YBD infections (21% or were in remission (31.6% but were missing on average >90% of their tissue. Although the incidence of YBD has declined since 2000, white plague (WP prevalence was unusually high (4-12% in 2001 and 2005, with affected colonies exhibiting recent mortality of up to 70%. Dead Montastraea spp. surfaces are being colonized by other corals, including poritids, agaricids, and other faviids, while recruits of M. annularis (complex are absent. If diseases and other biotic stressors persist on these reefs, M. annularis and M. faveolata populations may undergo a decline similar to that observed in the 1980s among Caribbean acroporids. Rev. Biol. Trop. 54 (Suppl. 3: 45- 58. Epub 2007 Jan. 15.

  15. Disruption of Rhino Demography by Poachers May Lead to Population Declines in Kruger National Park, South Africa.

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    Sam M Ferreira

    Full Text Available The onslaught on the World's rhinoceroses continues despite numerous initiatives aimed at curbing it. When losses due to poaching exceed birth rates, declining rhino populations result. We used previously published estimates and growth rates for black rhinos (2008 and white rhinos (2010 together with known poaching trends at the time to predict population sizes and poaching rates in Kruger National Park, South Africa for 2013. Kruger is a stronghold for the south-eastern black rhino and southern white rhino. Counting rhinos on 878 blocks 3x3 km in size using helicopters, estimating availability bias and collating observer and detectability biases allowed estimates using the Jolly's estimator. The exponential escalation in number of rhinos poached per day appears to have slowed. The black rhino estimate of 414 individuals (95% confidence interval: 343-487 was lower than the predicted 835 individuals (95% CI: 754-956. The white rhino estimate of 8,968 individuals (95% CI: 8,394-9,564 overlapped with the predicted 9,417 individuals (95% CI: 7,698-11,183. Density- and rainfall-dependent responses in birth- and death rates of white rhinos provide opportunities to offset anticipated poaching effects through removals of rhinos from high density areas to increase birth and survival rates. Biological management of rhinos, however, need complimentary management of the poaching threat as present poaching trends predict detectable declines in white rhino abundances by 2018. Strategic responses such as anti-poaching that protect supply from illegal harvesting, reducing demand, and increasing supply commonly require crime network disruption as a first step complimented by providing options for alternative economies in areas abutting protected areas.

  16. Disruption of Rhino Demography by Poachers May Lead to Population Declines in Kruger National Park, South Africa.

    Science.gov (United States)

    Ferreira, Sam M; Greaver, Cathy; Knight, Grant A; Knight, Mike H; Smit, Izak P J; Pienaar, Danie

    2015-01-01

    The onslaught on the World's rhinoceroses continues despite numerous initiatives aimed at curbing it. When losses due to poaching exceed birth rates, declining rhino populations result. We used previously published estimates and growth rates for black rhinos (2008) and white rhinos (2010) together with known poaching trends at the time to predict population sizes and poaching rates in Kruger National Park, South Africa for 2013. Kruger is a stronghold for the south-eastern black rhino and southern white rhino. Counting rhinos on 878 blocks 3x3 km in size using helicopters, estimating availability bias and collating observer and detectability biases allowed estimates using the Jolly's estimator. The exponential escalation in number of rhinos poached per day appears to have slowed. The black rhino estimate of 414 individuals (95% confidence interval: 343-487) was lower than the predicted 835 individuals (95% CI: 754-956). The white rhino estimate of 8,968 individuals (95% CI: 8,394-9,564) overlapped with the predicted 9,417 individuals (95% CI: 7,698-11,183). Density- and rainfall-dependent responses in birth- and death rates of white rhinos provide opportunities to offset anticipated poaching effects through removals of rhinos from high density areas to increase birth and survival rates. Biological management of rhinos, however, need complimentary management of the poaching threat as present poaching trends predict detectable declines in white rhino abundances by 2018. Strategic responses such as anti-poaching that protect supply from illegal harvesting, reducing demand, and increasing supply commonly require crime network disruption as a first step complimented by providing options for alternative economies in areas abutting protected areas.

  17. Stones of Light: The Use of Crystals in Maya Divination

    DEFF Research Database (Denmark)

    McGraw, John J.

    2016-01-01

    In this chapter, I aim to bridge the rewarding archaeological contributions from the earlier part of this volume to ethnographic work performed among contemporary Mayas, particularly as informed by ritual specialists. In considering the ritual use of quartz crystals by living Mayas we may gain...... of functional analysis that situate archaeological and ethnographic data without projecting a particularism onto Maya contexts that may be inappropriate given the local epistemologies. Finally, I draw from cognitive science and religious studies to present a theory regarding the popularity and importance...... of quartz crystals in ritual activity, not only among the Maya, but worldwide. It is hoped that the analyses presented not only clarify ideas regarding quartz crystals in divination, but more broadly address the nature and importance of scrying in Maya religion....

  18. The ‘End’ of the Maya Long Count? 2012 and the Classic Maya

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    Erik Boot

    2013-06-01

    Full Text Available The second meeting of the AISI (Associazione Italiana Studi Iberoamericani was dedicated to “Apocalypse” in Latin American literature. In the year of 2012 this particular subject was chosen as various non- and pseudo-scientific and New Age publications hold that the Maya Long Count ends in 2012, more specifically on December 21. In this essay I present a short overview on how the idea of an ‘end’ of the Maya Long Count emerged, which ancient Maya hieroglyphic texts (from the Late Classic Maya period, ca. A.D. 550-900 refer to this particular date, and what the only text (from the site of Tortuguero, Tabasco, Mexico that may tell us something on 2012 reveals. I also present a short historic overview of the quality of the drawing of the Tortuguero text and how these influenced earlier decipherments, translations, and interpretations of this text. Ultimately, the hieroglyphic text itself is analyzed and one detail is discusses in more detail, the verb root tzutz- and which different, but not necessarily mutually exclusive, meanings it has in Mayan languages.

  19. Ocean-wide Drivers of Migration Strategies and Their Influence on Population Breeding Performance in a Declining Seabird.

    Science.gov (United States)

    Fayet, Annette L; Freeman, Robin; Anker-Nilssen, Tycho; Diamond, Antony; Erikstad, Kjell E; Fifield, Dave; Fitzsimmons, Michelle G; Hansen, Erpur S; Harris, Mike P; Jessopp, Mark; Kouwenberg, Amy-Lee; Kress, Steve; Mowat, Stephen; Perrins, Chris M; Petersen, Aevar; Petersen, Ib K; Reiertsen, Tone K; Robertson, Gregory J; Shannon, Paula; Sigurðsson, Ingvar A; Shoji, Akiko; Wanless, Sarah; Guilford, Tim

    2017-12-18

    Which factors shape animals' migration movements across large geographical scales, how different migratory strategies emerge between populations, and how these may affect population dynamics are central questions in the field of animal migration [1] that only large-scale studies of migration patterns across a species' range can answer [2]. To address these questions, we track the migration of 270 Atlantic puffins Fratercula arctica, a red-listed, declining seabird, across their entire breeding range. We investigate the role of demographic, geographical, and environmental variables in driving spatial and behavioral differences on an ocean-basin scale by measuring puffins' among-colony differences in migratory routes and day-to-day behavior (estimated with individual daily activity budgets and energy expenditure). We show that competition and local winter resource availability are important drivers of migratory movements, with birds from larger colonies or with poorer local winter conditions migrating further and visiting less-productive waters; this in turn led to differences in flight activity and energy expenditure. Other behavioral differences emerge with latitude, with foraging effort and energy expenditure increasing when birds winter further north in colder waters. Importantly, these ocean-wide migration patterns can ultimately be linked with breeding performance: colony productivity is negatively associated with wintering latitude, population size, and migration distance, which demonstrates the cost of competition and migration on future breeding and the link between non-breeding and breeding periods. Our results help us to understand the drivers of animal migration and have important implications for population dynamics and the conservation of migratory species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Forests, fields, and the edge of sustainability at the ancient Maya city of Tikal.

    Science.gov (United States)

    Lentz, David L; Dunning, Nicholas P; Scarborough, Vernon L; Magee, Kevin S; Thompson, Kim M; Weaver, Eric; Carr, Christopher; Terry, Richard E; Islebe, Gerald; Tankersley, Kenneth B; Grazioso Sierra, Liwy; Jones, John G; Buttles, Palma; Valdez, Fred; Ramos Hernandez, Carmen E

    2014-12-30

    Tikal has long been viewed as one of the leading polities of the ancient Maya realm, yet how the city was able to maintain its substantial population in the midst of a tropical forest environment has been a topic of unresolved debate among researchers for decades. We present ecological, paleoethnobotanical, hydraulic, remote sensing, edaphic, and isotopic evidence that reveals how the Late Classic Maya at Tikal practiced intensive forms of agriculture (including irrigation, terrace construction, arboriculture, household gardens, and short fallow swidden) coupled with carefully controlled agroforestry and a complex system of water retention and redistribution. Empirical evidence is presented to demonstrate that this assiduously managed anthropogenic ecosystem of the Classic period Maya was a landscape optimized in a way that provided sustenance to a relatively large population in a preindustrial, low-density urban community. This landscape productivity optimization, however, came with a heavy cost of reduced environmental resiliency and a complete reliance on consistent annual rainfall. Recent speleothem data collected from regional caves showed that persistent episodes of unusually low rainfall were prevalent in the mid-9th century A.D., a time period that coincides strikingly with the abandonment of Tikal and the erection of its last dated monument in A.D. 869. The intensified resource management strategy used at Tikal-already operating at the landscape's carrying capacity-ceased to provide adequate food, fuel, and drinking water for the Late Classic populace in the face of extended periods of drought. As a result, social disorder and abandonment ensued.

  1. Climate-associated population declines reverse recovery and threaten future of an iconic high-elevation plant

    Science.gov (United States)

    Krushelnycky, Paul D.; Loope, Lloyd L.; Giambelluca, Thomas W.; Starr, Forest; Starr, Kim; Drake, Donald R.; Taylor, Andrew D.; Robichaux, Robert H.

    2013-01-01

    Although climate change is predicted to place mountain-top and other narrowly endemic species at severe risk of extinction, the ecological processes involved in such extinctions are still poorly resolved. In addition, much of this biodiversity loss will likely go unobserved, and therefore largely unappreciated. The Haleakalā silversword is restricted to a single volcano summit in Hawai‘i, but is a highly charismatic giant rosette plant that is viewed by 1–2 million visitors annually. We link detailed local climate data to a lengthy demographic record, and combine both with a population-wide assessment of recent plant mortality and recruitment, to show that after decades of strong recovery following successful management, this iconic species has entered a period of substantial climate-associated decline. Mortality has been highest at the lower end of the distributional range, where most silverswords occur, and the strong association of annual population growth rates with patterns of precipitation suggests an increasing frequency of lethal water stress. Local climate data confirm trends toward warmer and drier conditions on the mountain, and signify a bleak outlook for silverswords if these trends continue. The silversword example foreshadows trouble for diversity in other biological hotspots, and illustrates how even well-protected and relatively abundant species may succumb to climate-induced stresses.

  2. Climate-associated population declines reverse recovery and threaten future of an iconic high-elevation plant.

    Science.gov (United States)

    Krushelnycky, Paul D; Loope, Lloyd L; Giambelluca, Thomas W; Starr, Forest; Starr, Kim; Drake, Donald R; Taylor, Andrew D; Robichaux, Robert H

    2013-03-01

    Although climate change is predicted to place mountain-top and other narrowly endemic species at severe risk of extinction, the ecological processes involved in such extinctions are still poorly resolved. In addition, much of this biodiversity loss will likely go unobserved, and therefore largely unappreciated. The Haleakalā silversword is restricted to a single volcano summit in Hawai'i, but is a highly charismatic giant rosette plant that is viewed by 1-2 million visitors annually. We link detailed local climate data to a lengthy demographic record, and combine both with a population-wide assessment of recent plant mortality and recruitment, to show that after decades of strong recovery following successful management, this iconic species has entered a period of substantial climate-associated decline. Mortality has been highest at the lower end of the distributional range, where most silverswords occur, and the strong association of annual population growth rates with patterns of precipitation suggests an increasing frequency of lethal water stress. Local climate data confirm trends toward warmer and drier conditions on the mountain, and signify a bleak outlook for silverswords if these trends continue. The silversword example foreshadows trouble for diversity in other biological hotspots, and illustrates how even well-protected and relatively abundant species may succumb to climate-induced stresses. © 2012 Blackwell Publishing Ltd.

  3. Participation in population-based case-control studies: does the observed decline vary by socio-economic status?

    Science.gov (United States)

    Mazloum, Marie; Bailey, Helen D; Heiden, Tamika; Armstrong, Bruce K; de Klerk, Nicholas; Milne, Elizabeth

    2012-05-01

    An Australian study of childhood leukaemia (Aus-ALL) previously reported that control participation was positively associated with socio-economic status (SES). A similar study of childhood brain tumours (Aus-CBT) was carried out 4 years later, and this paper compares control participation and its relationship with SES in the two studies. To assess the representativeness of controls in terms of SES, the addresses of controls were linked to Australian Bureau of Statistics Census 2006 Collection Districts (CDs), and hence to area-based indices of SES. Independent sample t-tests and chi-squared tests were used to compare the SES indices of CDs where Aus-CBT controls lived with those where Aus-ALL controls lived and with those of all CDs where Australian families lived. The overall percentage of eligible families who agreed to participate was lower in Aus-CBT (53.9%) than in Aus-ALL (70.3%). Control families in both studies were of higher SES than the general population, while the distribution of SES among recruited controls was similar in both studies. These findings provide some reassurance that the observed decline in research participation over time may not be associated with an increasingly unrepresentative participant population. © 2012 Blackwell Publishing Ltd.

  4. Decline and recovery of a large carnivore: environmental change and long-term trends in an endangered brown bear population.

    Science.gov (United States)

    Martínez Cano, Isabel; Taboada, Fernando González; Naves, Javier; Fernández-Gil, Alberto; Wiegand, Thorsten

    2016-11-30

    Understanding what factors drive fluctuations in the abundance of endangered species is a difficult ecological problem but a major requirement to attain effective management and conservation success. The ecological traits of large mammals make this task even more complicated, calling for integrative approaches. We develop a framework combining individual-based modelling and statistical inference to assess alternative hypotheses on brown bear dynamics in the Cantabrian range (Iberian Peninsula). Models including the effect of environmental factors on mortality rates were able to reproduce three decades of variation in the number of females with cubs of the year (Fcoy), including the decline that put the population close to extinction in the mid-nineties, and the following increase in brown bear numbers. This external effect prevailed over density-dependent mechanisms (sexually selected infanticide and female reproductive suppression), with a major impact of climate driven changes in resource availability and a secondary role of changes in human pressure. Predicted changes in population structure revealed a nonlinear relationship between total abundance and the number of Fcoy, highlighting the risk of simple projections based on indirect abundance indices. This study demonstrates the advantages of integrative, mechanistic approaches and provides a widely applicable framework to improve our understanding of wildlife dynamics. © 2016 The Author(s).

  5. The University of Texas Maya Muon Project

    International Nuclear Information System (INIS)

    Schwitters, Roy

    2007-01-01

    Plans to explore the ruin of a Maya Pyramid in Belize using cosmic ray muon tomography will be described. Muon tomography was pioneered by Luis Alvarez in the 1960's to explore the Second Pyramid of Chephren in Egypt. Improvements in detector technology since the Alvarez experiment suggest that muon tomography may be a practical method for exploring and monitoring relatively large underground volumes when exposure times of order months are acceptable. A prototype detector based on Fermilab/MINOS scintillator strip/WLS fiber technology has been built and is being tested at UT Austin. Initial results using the detector will be discussed.

  6. Estimating trends of population decline in long-lived marine species in the Mediterranean Sea based on fishers' perceptions.

    Directory of Open Access Journals (Sweden)

    Francesc Maynou

    Full Text Available We conducted interviews of a representative sample of 106 retired fishers in Italy, Spain and Greece, asking specific questions about the trends they perceived in dolphin and shark abundances between 1940 and 1999 (in three 20 year periods compared to the present abundance. The large marine fauna studied were not target species of the commercial fleet segment interviewed (trawl fishery. The fishers were asked to rank the perceived abundance in each period into qualitative ordinal classes based on two indicators: frequency of sightings and frequency of catches (incidental or intentional of each taxonomic group. The statistical analysis of the survey results showed that both incidental catches and the sighting frequency of dolphins have decreased significantly over the 60+ years of the study period (except for in Greece due to the recent population increase. This shows that fishers' perceptions are in agreement with the declining population trends detected by scientists. Shark catches were also perceived to have diminished since the early 1940s for all species. Other long-lived Mediterranean marine fauna (monk seals, whales were at very low levels in the second half of the 20(th century and no quantitative data could be obtained. Our study supports the results obtained in the Mediterranean and other seas that show the rapid disappearance (over a few decades of marine fauna. We show that appropriately designed questionnaires help provide a picture of animal abundance in the past through the valuable perceptions of fishers. This information can be used to complement scientific sources or in some cases be taken as the only information source for establishing population trends in the abundance of sensitive species.

  7. A method for investigating population declines of migratory birds using stable isotopes: origins of harvested lesser scaup in North America.

    Directory of Open Access Journals (Sweden)

    Keith A Hobson

    2009-11-01

    Full Text Available Elucidating geographic locations from where migratory birds are recruited into adult breeding populations is a fundamental but largely elusive goal in conservation biology. This is especially true for species that breed in remote northern areas where field-based demographic assessments are logistically challenging.Here we used hydrogen isotopes (deltaD to determine natal origins of migrating hatch-year lesser scaup (Aythya affinis harvested by hunters in the United States from all North American flyways during the hunting seasons of 1999-2000 (n = 412 and 2000-2001 (n = 455. We combined geospatial, observational, and analytical data sources, including known scaup breeding range, deltaD values of feathers from juveniles at natal sites, models of deltaD for growing-season precipitation, and scaup band-recovery data to generate probabilistic natal origin landscapes for individual scaup. We then used Monte Carlo integration to model assignment uncertainty from among individual deltaD variance estimates from birds of known molt origin and also from band-return data summarized at the flyway level. We compared the distribution of scaup natal origin with the distribution of breeding population counts obtained from systematic long-term surveys.Our analysis revealed that the proportion of young scaup produced in the northern (above 60 degrees N versus the southern boreal and Prairie-Parkland region was inversely related to the proportions of breeding adults using these regions, suggesting that despite having a higher relative abundance of breeding adults, the northern boreal region was less productive for scaup recruitment into the harvest than more southern biomes. Our approach for evaluating population declines of migratory birds (particularly game birds synthesizes all available distributional data and exploits the advantages of intrinsic isotopic markers that link individuals to geography.

  8. Deforestation Along the Maya Mountain Massif Belize-Guatemala Border

    Science.gov (United States)

    Chicas, S. D.; Omine, K.; Arevalo, B.; Ford, J. B.; Sugimura, K.

    2016-06-01

    In recent years trans-boundary incursions from Petén, Guatemala into Belize's Maya Mountain Massif (MMM) have increased. The incursions are rapidly degrading cultural and natural resources in Belize's protected areas. Given the local, regional and global importance of the MMM and the scarcity of deforestation data, our research team conducted a time series analysis 81 km by 12 km along the Belize-Guatemalan border adjacent to the protected areas of the MMM. Analysis drew on Landsat imagery from 1991 to 2014 to determine historic deforestation rates. The results indicate that the highest deforestation rates in the study area were -1.04% and -6.78% loss of forested area per year in 2012-2014 and 1995-1999 respectively. From 1991 to 2014, forested area decreased from 96.9 % to 85.72 % in Belize and 83.15 % to 31.52 % in Guatemala. During the study period, it was clear that deforestation rates fluctuated in Belize's MMM from one time-period to the next. This seems linked to either a decline in deforestation rates in Guatemala, the vertical expansion of deforestation in Guatemalan forested areas and monitoring. The results of this study urge action to reduce incursions and secure protected areas and remaining forest along the Belize-Guatemalan border.

  9. DEFORESTATION ALONG THE MAYA MOUNTAIN MASSIF BELIZE-GUATEMALA BORDER

    Directory of Open Access Journals (Sweden)

    S. D. Chicas

    2016-06-01

    Full Text Available In recent years trans-boundary incursions from Petén, Guatemala into Belize’s Maya Mountain Massif (MMM have increased. The incursions are rapidly degrading cultural and natural resources in Belize’s protected areas. Given the local, regional and global importance of the MMM and the scarcity of deforestation data, our research team conducted a time series analysis 81 km by 12 km along the Belize-Guatemalan border adjacent to the protected areas of the MMM. Analysis drew on Landsat imagery from 1991 to 2014 to determine historic deforestation rates. The results indicate that the highest deforestation rates in the study area were −1.04% and −6.78% loss of forested area per year in 2012-2014 and 1995-1999 respectively. From 1991 to 2014, forested area decreased from 96.9 % to 85.72 % in Belize and 83.15 % to 31.52 % in Guatemala. During the study period, it was clear that deforestation rates fluctuated in Belize's MMM from one time-period to the next. This seems linked to either a decline in deforestation rates in Guatemala, the vertical expansion of deforestation in Guatemalan forested areas and monitoring. The results of this study urge action to reduce incursions and secure protected areas and remaining forest along the Belize-Guatemalan border.

  10. Cultural and Climatic History of Cobá, a Lowland Maya City in Quintana Roo, Mexico

    Science.gov (United States)

    Leyden, Barbara W.; Brenner, Mark; Dahlin, Bruce H.

    1998-01-01

    Lake Cobá, within the archaeological site of Cobá, provides evidence bearing on lowland Maya development. Palynological and geochemical data record multidecadal precipitation cycles from a 8.80-m, >8370-yr lake-sediment sequence terminating on bedrock. Late Classic sedimentation rates are rapid, but an anthropogenically derived colluvium layer is lacking. Initial vegetation was medium semi-deciduous and swamp forest. Forest clearance began 1650 B.C. (Early Preclassic) and maize first occurred at 850 B.C. (Middle Preclassic). Lakeside milpas existed until A.D. 720 (Late Classic) and then were moved from the city center as urbanization intensified and Lake Cobá was diked as a reservoir. Cobá was at most briefly vacated during the Classic Collapse and was abandoned after A.D. 1240, although some habitation persisted. The paleoecological record matches the archaeological history for Cobá, but pervasive disturbance muted the climatic signal, as the Late Classic drought is barely evident. The question whether economic trees were maintained within the city is unresolved. Maize cultivation allowed the Maya to develop a complex society and support a large population, but dependence on maize was ultimately doomed by variable rainfall. Precipitation in extreme years was insufficient to support crops, while native vegetation was not directly affected by drought that devastated Maya agriculture.

  11. Patterned Ground in Wetlands of the Maya Lowlands: Anthropogenic and Natural Causes

    Science.gov (United States)

    Beach, T.; Beach, S. L.

    2004-12-01

    We use geological and archaeological evidence to understand the formation of patterned ground in perennial and seasonal wetlands in the karst depressions of Belize and Guatemala. Some scholars have argued that these features are the remnants of ancient Maya wetland fields, chinampas, on which intensive cultivation produced food that could begin to nourish the extremely high population of the Late Classic (A.D. 550-850). Others have argued that these were natural features or that they represent landscape manipulation for rising sea level in the Preclassic (1000 B.C. -A.D. 250). We present the evidence for ancient intensive agriculture and natural landscape formation with multiple proxies: excavated field and canal features, artifacts, pollen, soil stratigraphy, and water chemistry. Evidence thus far suggests that many regional depressions have Preclassic (1200 BC to AD 200) or earlier paleosols, buried from 1-2 m by eroded soils induced by Maya land use practices. These paleosols were buried by eroded sediments from uplands and by precipitation of gypsum from rising groundwater. The sedimentation occurred largely between the Preclassic and Late Classic, when ancient Maya farmers built canals in pre-existing low spots to reclaim these wetlands. Thus, stable natural processes, environmental change, and human manipulation have acted together to form patterned wetland ground over the later Holocene.

  12. Ancient and contemporary DNA reveal a pre-human decline but no population bottleneck associated with recent human persecution in the kea (Nestor notabilis.

    Directory of Open Access Journals (Sweden)

    Nicolas Dussex

    Full Text Available The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis. Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000-5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410, historical (n = 15 and fossil samples (n = 4 showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 - 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines.

  13. Ancient and contemporary DNA reveal a pre-human decline but no population bottleneck associated with recent human persecution in the kea (Nestor notabilis).

    Science.gov (United States)

    Dussex, Nicolas; Rawlence, Nicolas J; Robertson, Bruce C

    2015-01-01

    The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis). Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000-5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410), historical (n = 15) and fossil samples (n = 4) showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial) but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 - 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines.

  14. Ancient and Contemporary DNA Reveal a Pre-Human Decline but No Population Bottleneck Associated with Recent Human Persecution in the Kea (Nestor notabilis)

    Science.gov (United States)

    Dussex, Nicolas; Rawlence, Nicolas J.; Robertson, Bruce C.

    2015-01-01

    The impact of population bottlenecks is an important factor to consider when assessing species survival. Population declines can considerably limit the evolutionary potential of species and make them more susceptible to stochastic events. New Zealand has a well documented history of decline of endemic avifauna related to human colonization. Here, we investigate the genetic effects of a recent population decline in the endangered kea (Nestor notabilis). Kea have undergone a long-lasting persecution between the late 1800s to 1970s where an estimated 150,000 kea were culled under a governmental bounty scheme. Kea now number 1,000–5,000 individuals in the wild and it is likely that the recent population decline may have reduced the genetic diversity of the species. Comparison of contemporary (n = 410), historical (n = 15) and fossil samples (n = 4) showed a loss of mitochondrial diversity since the end of the last glaciation (Otiran Glacial) but no loss of overall genetic diversity associated with the cull. Microsatellite data indicated a recent bottleneck for only one population and a range-wide decline in Ne dating back some 300 – 6,000 years ago, a period predating European arrival in NZ. These results suggest that despite a recent human persecution, kea might have experienced a large population decline before stabilizing in numbers prior to human settlement of New Zealand in response to Holocene changes in habitat distribution. Our study therefore highlights the need to understand the respective effects of climate change and human activities on endangered species dynamics when proposing conservation guidelines. PMID:25719752

  15. Decline in Mycobacterium bovis and Brucella abortus populations during the maturation of experimentally contaminated parmesan-type cheese

    Directory of Open Access Journals (Sweden)

    Karina Ramirez Starikoff

    2016-11-01

    Full Text Available Brazilian legislation allows the manufacture of raw milk cheese with a maturation exceeding 60 days at room temperature above 5°C, but there is a lack of solid scientific evidence on the efficacy of this maturation process in inactivating important pathogens that may be present in milk, such as Mycobacterium bovis and Brucella abortus. Thus, the objectives of this study were to produce parmesan-type cheese experimentally contaminated with M. bovis and B. abortus and evaluate the survival of these pathogens along 2-month maturation. Parmesan-type cheese was manufactured in the laboratory using whole pasteurized milk with or without inoculation with M. bovis (SB1033 or B. abortus (1119-3 and matured at 18°C for up to 63 days. M. bovis was inoculated in Stonebrink-Leslie medium supplemented with antibiotics and incubated at 37°C for 45 days, and B. abortus was incubated in Farrel medium at 36°C for 3 days. The average D18°C value, weighted by variance, was 37.5 ± 5.3 days for M. bovis and 5.9 ± 0.7 days for B. abortus. The average physicochemical parameters in the cheese at the end of the study were as follows: pH = 4.89, water activity = 0.976, and moisture percentage = 43.1%. The pH might have contributed to the reduction in the population of B. abortus but seems not to have influenced the population of M. bovis. We conclude that the duration of the maturation process influences the size of the surviving populations of M. bovis and B. abortus, and that the shortening of the maturation duration might not ensure a decline in pathogen levels to safe levels. Thus, complementary studies considering the effect of several other technological aspects on the survival of these pathogens are required, including the effect of the lactic acid bacterial population, salt content, and temperature of maturation.

  16. Genetic consequences of population decline in the European otter ( Lutra lutra ) : an assessment of microsatellite DNA variation in Danish otters from 1883 to 1993

    DEFF Research Database (Denmark)

    Pertoldi, C.; Hansen, Michael Møller; Loeschcke, V.

    2001-01-01

    alleles, suggested that a drastic long-term population decline has taken place, which could have started more than 2000 years ago, possibly due to ancient anthropogenic pressure. Finally, assignment tests and pairwise F-ST values suggested weak but statistically significant genetic differentiation between......The European otter (Lutra lutra) was common in Denmark until the 1960s, but its present distribution encompasses only a minor part of the country. The aim of this study was to assess whether the recent population decline has resulted in loss of genetic variability and to gain further insight...

  17. Breeding ecology of the southern shrike, Lanius meridionalis, in an agrosystem of south–eastern Spain: the surprisingly excellent breeding success in a declining population

    Energy Technology Data Exchange (ETDEWEB)

    Moreno-Rueda, G.; Abril-Colon, I.; Lopez-Orta, A.; Alvarez-Benito, I.; Castillo-Gomez, C.; Comas, M.; Rivas, J.M.

    2016-07-01

    The southern shrike, Lanius meridionalis, is declining at the Spanish and European level. One cause of this decline could be low reproductive success due to low availability of prey in agricultural environments. To investigate this possibility we analysed the breeding ecology of a population of southern shrike in an agrosystem in Lomas de Padul (SE Spain). Our results suggest the population is declining in this area. However, contrary to expectations, the population showed the highest reproductive success (% nests in which at least one egg produces a fledgling) reported for this species to date (83.3%), with a productivity of 4.04 fledglings per nest. Reproductive success varied throughout the years, ranging from 75% in the worst year to 92.9% in the best year. Similarly, productivity ranged from 3.25 to 5.0 fledglings per nest depending on the year. Other aspects of reproductive biology, such as clutch size, brood size, and nestling diet, were similar to those reported in other studies. Based on these results, we hypothesise that the determinant of population decline acts on the juvenile fraction, drastically reducing the recruitment rate, or affecting the dispersion of adults and recruits. Nevertheless, the exact factor or factors are unknown. This study shows that a high reproductive success does not guarantee good health status of the population. (Author)

  18. Foraging habitat quality constrains effectiveness of artificial nest-site provisioning in reversing population declines in a colonial cavity nester.

    Directory of Open Access Journals (Sweden)

    Inês Catry

    Full Text Available Among birds, breeding numbers are mainly limited by two resources of major importance: food supply and nest-site availability. Here, we investigated how differences in land-use and nest-site availability affected the foraging behaviour, breeding success and population trends of the colonial cavity-dependent lesser kestrel Falco naumanni inhabiting two protected areas. Both areas were provided with artificial nests to increase nest-site availability. The first area is a pseudo-steppe characterized by traditional extensive cereal cultivation, whereas the second area is a previous agricultural zone now abandoned or replaced by forested areas. In both areas, lesser kestrels selected extensive agricultural habitats, such as fallows and cereal fields, and avoided scrubland and forests. In the second area, tracked birds from one colony travelled significantly farther distances (6.2 km ± 1.7 vs. 1.8 km ± 0.4 and 1.9 km ± 0.6 and had significant larger foraging-ranges (144 km(2 vs. 18.8 and 14.8 km(2 when compared to the birds of two colonies in the extensive agricultural area. Longer foraging trips were reflected in lower chick feeding rates, lower fledging success and reduced chick fitness. Availability and occupation of artificial nests was high in both areas but population followed opposite trends, with a positive increment recorded exclusively in the first area with a large proportion of agricultural areas. Progressive habitat loss around the studied colony in the second area (suitable habitat decreased from 32% in 1990 to only 7% in 2002 is likely the main driver of the recorded population decline and suggests that the effectiveness of bird species conservation based on nest-site provisioning is highly constrained by habitat quality in the surrounding areas. Therefore, the conservation of cavity-dependent species may be enhanced firstly by finding the best areas of remaining habitat and secondly by increasing the carrying capacity of high

  19. Metabolic syndrome but not obesity measures are risk factors for accelerated age-related glomerular filtration rate decline in the general population.

    Science.gov (United States)

    Stefansson, Vidar T N; Schei, Jørgen; Solbu, Marit D; Jenssen, Trond G; Melsom, Toralf; Eriksen, Bjørn O

    2018-05-01

    Rapid age-related glomerular filtration rate (GFR) decline increases the risk of end-stage renal disease, and a low GFR increases the risk of mortality and cardiovascular disease. High body mass index and the metabolic syndrome are well-known risk factors for patients with advanced chronic kidney disease, but their role in accelerating age-related GFR decline independent of cardiovascular disease, hypertension and diabetes is not adequately understood. We studied body mass index, waist circumference, waist-hip ratio and metabolic syndrome as risk factors for accelerated GFR decline in 1261 middle-aged people representative of the general population without diabetes, cardiovascular disease or kidney disease. GFR was measured as iohexol clearance at baseline and repeated after a median of 5.6 years. Metabolic syndrome was defined as fulfilling three out of five criteria, based on waist circumference, blood pressure, glucose, high-density lipoprotein cholesterol and triglycerides. The mean GFR decline rate was 0.95 ml/min/year. Neither the body mass index, waist circumference nor waist-hip ratio predicted statistically significant changes in age-related GFR decline, but individuals with baseline metabolic syndrome had a significant mean of 0.30 ml/min/year faster decline than individuals without metabolic syndrome in a multivariable adjusted linear regression model. This association was mainly driven by the triglyceride criterion of metabolic syndrome, which was associated with a significant 0.36 ml/min/year faster decline when analyzed separately. Results differed significantly when GFR was estimated using creatinine and/or cystatin C. Thus, metabolic syndrome, but not the body mass index, waist circumference or waist-hip ratio, is an independent risk factor for accelerated age-related GFR decline in the general population. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  20. Miniature sonar for obstacle detection on samll AUV Maya

    Digital Repository Service at National Institute of Oceanography (India)

    Afzulpurkar, S.; Desa, E.; Navelkar, G.; Mascarenhas, A.A.M.Q.; Maurya, P.K.; Martins, H.; Madhan, R.; Prabhudesai, S.; Pinto, R.; Marchon, N.

    that are communicated to the mission computer of Maya which uses a distributed CAN network architecture for internal subsystem communications. The mission computer can use this new heading data for navigation accordingly....

  1. Objetual Regime of the Maya during Classic period, a proposal

    Directory of Open Access Journals (Sweden)

    Antonio Jaramillo Arango

    2016-06-01

    Full Text Available Within the academic archaeology of the 20th Century, objects were only considered as sources for understanding human action. Based on recent theoretic anthropological proposals, this paper proposes a recursive archaeology, that is, to include the Classic Maya concepts as part of our analysis in order to understand things as truly protagonists of social relationships. In the Maya area, objects have different ways of being in the world which have been identified by the archeology of the Classic period: person-objects, parts of a dividual body and machines. These three ways are explored here through archaeologic contexts and epigraphic texts with the aim of approaching the construction of reality of the Classic Maya. With a multidisciplinary analysis that includes archaeology, epigraphy, history, linguistics and anthropology, a high number of examples coming from different regions in the Maya area is examined. Thus, an overall view of this phenomenon is presented.

  2. Peopling the past: New perspectives on the ancient Maya

    OpenAIRE

    Robin, Cynthia

    2001-01-01

    The new direction in Maya archaeology is toward achieving a greater understanding of people and their roles and their relations in the past. To answer emerging humanistic questions about ancient people's lives Mayanists are increasingly making use of new and existing scientific methods from archaeology and other disciplines. Maya archaeology is bridging the divide between the humanities and sciences to answer questions about ancient people previously considered bey...

  3. Objetual Regime of the Maya during Classic period, a proposal

    OpenAIRE

    Antonio Jaramillo Arango

    2016-01-01

    Within the academic archaeology of the 20th Century, objects were only considered as sources for understanding human action. Based on recent theoretic anthropological proposals, this paper proposes a recursive archaeology, that is, to include the Classic Maya concepts as part of our analysis in order to understand things as truly protagonists of social relationships. In the Maya area, objects have different ways of being in the world which have been identified by the archeology of the Classic...

  4. Peopling the past: new perspectives on the ancient Maya.

    Science.gov (United States)

    Robin, C

    2001-01-02

    The new direction in Maya archaeology is toward achieving a greater understanding of people and their roles and their relations in the past. To answer emerging humanistic questions about ancient people's lives Mayanists are increasingly making use of new and existing scientific methods from archaeology and other disciplines. Maya archaeology is bridging the divide between the humanities and sciences to answer questions about ancient people previously considered beyond the realm of archaeological knowledge.

  5. Hydroperiod and cattle use associated with lower recruitment in an r-selected amphibian with a declining population trend in the Klamath Mountains, California

    Science.gov (United States)

    Esther M. Cole; Rosemary Hartman; Malcolm P. North

    2016-01-01

    Recent population declines in amphibians associated with mortality in early life stages highlight the need for a better understanding of the environmental factors related to successful survival to metamorphosis. In our study, we closely examine the relative importance of environmental factors to three stages of recruitment for Cascade frogs (Rana cascadae...

  6. Amphibian populations in the terrestrial environment: Is there evidence of declines of terrestrial forest amphibians in northwestern California?

    Science.gov (United States)

    Hartwell H. Welsh Jr.; Gary M. Fellers; Amy J. Lind

    2007-01-01

    Amphibian declines have been documented worldwide; however the vast majority are species associated with aquatic habitats. Information on the status and trends of terrestrial amphibians is almost entirely lacking. Here we use data collected across a 12-yr period (sampling from 1984–86 and from 1993–95) to address the question of whether evidence exists for declines...

  7. Fractures as an independent predictor of functional decline in older people: a population-based study with an 8-year follow-up.

    Science.gov (United States)

    Piirtola, Maarit; Löppönen, Minna; Vahlberg, Tero; Isoaho, Raimo; Kivelä, Sirkka-Liisa; Räihä, Ismo

    2012-01-01

    Fractures among older people are common, but there is scant evidence about the impact of fractures on functional decline in an unselected older population. The objective of this study was to analyze the impact of lower and upper body fractures on functional performance among older adults during an 8-year follow-up. A population-based cohort of 616 Finnish persons aged 65 and over was followed for up to 8 years, and the association between fractures and the risk of short-term (0-2 years) and long-term (up to 8 years) functional decline was analyzed. Fractures were categorized according their functional influence on mobility and activities of daily living (ADL) into lower and upper body fractures. Multivariate cumulative logistic regression model was used in the analyses. During the 8-year follow-up, 112 (18%) persons sustained at least one fracture. In the multivariate analyses, lower body fractures predicted both short-term and long-term decline in mobility [cumulative odds ratio (COR) 4.7, 95% confidence interval (95% CI) 1.9-11.7 and COR 2.6, 95% CI 1.1-6.2, respectively] and in ADL performance (COR 3.1, 95% CI 1.3-7.6 and COR 4.7, 95% CI 2.0-11.4, respectively). Upper body fractures predicted decline in ADL performance during the long-term follow-up (COR 2.5, 95% CI 1.3-4.8). Pre-fracture functional decline and inactivity in leisure time physical exercise were independently associated with the risk of decline in extensive activities. Fractures have an independent influence on the development of functional decline in older persons regardless of the pre-fracture health. Prevention of falls and fractures and improvement of treatment, rehabilitation and follow-up process after fractures are needed. Copyright © 2011 S. Karger AG, Basel.

  8. The Maya Tropical Forest: Cascading Human impacts from Hillslopes to Floodplains

    Science.gov (United States)

    Beach, Timothy; Luzzadder-Beach, Sheryl; Doyle, Colin; Krause, Samantha; Brokaw, Nicholas; Yaeger, Jason

    2016-04-01

    We review the long-term human impact on fluvial systems in the Maya tropical forest region. Although most of this karstic region is drained by groundwater, the southern and coastal margins have several river systems that drain volcanic and metamorphic as well as sedimentary terrains. Some positive environmental impacts of Maya Civilization were the long-term impacts of both landesque capital, like wetland field systems, and other land uses that have enriched many soils. Some negative impacts included stripped soils and eutrophic rivers, both playing out again today with recent deforestation and intensive agriculture. We review trends in the region's fluvial systems, present new evidence on beneficial and detrimental impacts of Maya civilization, and present a new study using LiDAR mapping of fluvial geomorphology of the Belize River. Our new field research comes from the transboundary Rio Bravo watershed of Belize and Guatemala near the border with Mexico. This watershed today is mainly a well preserved tropical forest but from 3,000 to 1000 years ago was partly deforested by Maya cities, farms, roads, fires, and fields. We present studies of soils and sediment movement along slopes, floodplains, and water quality impacts of high dissolved loads of sulfate and calcium. We use AMS dates and soil stratigraphy to date slope and floodplain flux, and we use multiple proxies like pollen and carbon isotopes to reconstruct ancient land use. Aggradation in the floodplain and colluvial deposits began by at least 3,000 years ago and continued until 1100 years ago in several study sites. Some Classic period sites with peak human population and land use intensity experienced less soil erosion, perhaps due to soil conservation, post urban construction, and source reduction. Additional evidence suggests that ancient terraced sites and colluvial slopes that gained upslope sediment and soil nutrients from ancient Maya erosion had greater biodiversity. Lastly, we map fluvial

  9. Declination Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Declination is calculated using the current International Geomagnetic Reference Field (IGRF) model. Declination is calculated using the current World Magnetic Model...

  10. An autonomous underwater vehicle "Maya", for monitoring coastal waters, estuaries, rivers and dams

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.A; Navelkar, G.S.; Madhan, R.; Dabholkar, N.A; Prabhudesai, S.P.; Maurya, P.K.; Desa, E.; Afzulpurkar, S.; Suresh, T.; Matondkar, S.G.P.; Mahalunkar, A

    This article demonstrates the use of Maya, Autonomous Underwater Vehicle (AUV) for monitoring coastal waters, estuaries, rivers and dams. Maya is a mono hull structure with detachable nose and tail cones. The nose cone is mission specific...

  11. Significant decline in case fatality after acute myocardial infarction in Denmark--a population-based study from 1994 to 2001

    DEFF Research Database (Denmark)

    Abildstrom, Steen Z; Rasmussen, Søren; Madsen, Mette

    2002-01-01

    OBJECTIVE: We evaluated trends in in-hospital case fatality after acute myocardial infarction (AMI) in Denmark and analysed changes in the hospitalization rate for AMI. DESIGN: National population-based registries were used to identify patients (> or =30 years) who were admitted for their first AMI...... from 1994 to 2001. RESULTS: The annual relative decline in case-fatality rate was constant at 10.5% (95% confidence interval (CI) 9.5-11.5%). The decline was similar for both genders at all ages. The hospitalization rate decreased from 1994 to 1999 at an annual average of 4.3% (95% CI 3.......4-5.1%). In 2000 and 2001 the average annual increase was 7-8%. CONCLUSION: The case-fatality rate after AMI declined significantly in Denmark, similar to other Western countries, but the level is still higher than that of the USA. The increasing hospitalization rate coincided with changes in risk factors...

  12. Regular physical activity modifies smoking-related lung function decline and reduces risk of chronic obstructive pulmonary disease: a population-based cohort study

    DEFF Research Database (Denmark)

    Garcia-Aymerich, J; Lange, Peter; Benet, M

    2007-01-01

    RATIONALE: We have previously reported that regular physical activity reduces risk of chronic obstructive pulmonary disease (COPD) exacerbation. We hypothesized that higher levels of regular physical activity could reduce the risk of COPD by modifying smoking-related lung function decline....... OBJECTIVE: To estimate the longitudinal association between regular physical activity and FEV(1) and FVC decline and COPD risk. METHODS: A population-based sample (n = 6,790) was recruited and assessed with respect to physical activity, smoking, lung function, and other covariates, in Copenhagen in 1981....../yr of FEV(1), P-for-trend = 0.006, and +2.6 and +7.7 ml/yr of FVC, P-for-trend function decline. Active smokers with moderate to high physical activity had...

  13. Migration to the Maya Biosphere Reserve, Guatemala: Why place matters.

    Science.gov (United States)

    Carr, David L

    2008-01-01

    Virtually all migration research examines international migration or urbanization. Yet understudied rural migrants are of critical concern for environmental conservation and rural sustainable development. Despite the fact that a relatively small number of all migrants settle remote rural frontiers, these are the agents responsible for perhaps most of the tropical deforestation on the planet. Further, rural migrants are among the most destitute people worldwide in terms of economic and human development. While a host of research has investigated deforestation resulting from frontier migration, and a modest literature has emerged on frontier development, this article explores the necessary antecedent to tropical deforestation and poverty along agricultural frontiers: out-migration from origin areas. The data come from a 2000 survey with community leaders and key informants in 16 municipios of migrant origin to the Maya Biosphere Reserve (MBR), Petén, Guatemala. A common denominator among communities of migration origin to the Petén frontier was unequal resource access, usually land. Nevertheless, the factors driving resource scarcity were widely variable. Land degradation, land consolidation, and population growth prevailed in some communities but not in others. Despite similar exposure to community and regional level push factors, most people in the sampled communities did not out-migrate, suggesting that any one or combination of factors is not necessarily sufficient for out-migration.

  14. Materiales Maria Maya: community-based materials development.

    Science.gov (United States)

    Moran, B C

    1982-01-01

    Materials Maria Maya (MMM) is a Guatemalan organization which has dedicated itself to making health education more relevant to the rural Mayans who constitute the majority of Guatemala's population. The administration and direction of the project is in the hands of a team of qualified Mayan men and women. Funding is primarily through various charitable international organizations. The content of preexisting health education programs, strongly influenced by the dominant "ladino" Spanish speaking culture was found to be inappropriate to the goal of this program. MMM set about to formulate a new teaching format which would draw upon, rather than trample over, established cultural practices and life styles. By a process of trial and error, involving small scale field tests, a new program format was developed. By questioning local women about perceived priority areas, through the study of morbidity and mortality data, decisions were made as to topics to be covered. Investigators, authors, and artists worked together to form a "materials package" which was then subject to pretesting. Out of this effort, MMM has been able to come up with a method to encourage more effective participative teaching through the use of education materials.

  15. The recent decline of Montastraea annularis (complex coral populations in western Curaçao: a cause for concern?

    Directory of Open Access Journals (Sweden)

    A. W Bruckner

    2006-12-01

    Full Text Available Shallow leeward reefs off the western end of Curaçao are dominated by extensive populations of M. annularis (complex. These species are larger in size (mean= 66 cm diameter than all other species, with few small colonies (10 cm observed within transects, and most exhibited low levels of partial mortality (mean= 22.5%. These species were less abundant (38% of all colonies in 2005. Partial mortality among live colonies of M. annularis and M. faveolata increased by 85% (mean = 42% partial mortality and numerous dead colonies of M. faveolata and M. annularis were observed; M. franksi colonies were generally in excellent condition (14% partial tissue mortality. A high prevalence of coral diseases (3-30% was documented among M. annularis and M. faveolata, while all other species were less frequently affected. Yellow band disease (YBD emerged shortly after the 1995 bleaching event, and rapidly spread throughout all depths, with the highest prevalence between 1997-1999. YBD caused slow rates of mortality (=1 cm/month, but multiple focal lesions appeared on individual colonies, and these progressively radiated outward as they killed the colonies. By 2005, 44% of the tagged corals were dead; the remainder exhibited active YBD infections (21% or were in remission (31.6% but were missing on average >90% of their tissue. Although the incidence of YBD has declined since 2000, white plague (WP prevalence was unusually high (4-12% in 2001 and 2005, with affected colonies exhibiting recent mortality of up to 70%. Dead Montastraea spp. surfaces are being colonized by other corals, including poritids, agaricids, and other faviids, while recruits of M. annularis (complex are absent. If diseases and other biotic stressors persist on these reefs, M. annularis and M. faveolata populations may undergo a decline similar to that observed in the 1980s among Caribbean acroporids. Rev. Biol. Trop. 54 (Suppl. 3: 45- 58. Epub 2007 Jan. 15.Los arrecifes someros a sotavento

  16. Decline in Physical Function and Risk for Elder Abuse Reported to Social Services in a Community-Dwelling Population of Older Adults

    Science.gov (United States)

    Dong, XinQi; Simon, Melissa; Evans, Denis

    2012-01-01

    Objectives Elder abuse is an important public health and human rights issue and is associated with increased morbidity and mortality. This study aimed to examine the longitudinal association between decline in physical function and the risk for elder abuse. Design Prospective population-based study Setting Geographically defined community in Chicago. Participants Chicago Health and Aging Project (CHAP) is a population-based study (N=6,159), and we identified 143 CHAP participants who had elder abuse reported to social services agency from 1993–2010. Participants The primary independent variable was objectively assessed physical function using decline in physical performance testing (Tandem stand, measured walk and chair stand). Secondary independent variables were assessed using the decline in self-reported Katz, Nagi, and Rosow-Breslau scales. Outcomes were reported and confirmed elder abuse and specific subtypes of elder abuse (physical, psychological, caregiver neglect and financial exploitation). Logistic regression models were used to assess the association of decline in physical function measures and risk for elder abuse. Results After adjusting for potential confounders, every 1 point decline in physical performance testing (OR, 1.13(1.06–1.19)), Katz impairment (OR, 1.29(1.15–1.45)), Nagi impairment (OR, 1.30(1.13–1.49)) and Rosow Breslau impairment (OR, 1.42(1.15–1.74)) were associated with increased risk for elder abuse. Lowest tertiles of physical performance testing (OR, 4.92 (1.39–17.46), highest tertiles of Katz impairment (OR, 3.99 (2.18–7.31), Nagi impairment (OR, 2.37 (1.08–5.23), and Rosow Breslau impairment (2.85 (1.39–5.84) were associated with increased risk for elder abuse. Conclusion Decline in objectively assessed physical function and self-reported physical function are associated with increased risk for elder abuse. PMID:23002901

  17. Archaeological application of airborne LiDAR to examine social changes in the Ceibal region of the Maya lowlands

    Science.gov (United States)

    Triadan, Daniela; Pinzón, Flory; Burham, Melissa; Ranchos, José Luis; Aoyama, Kazuo; Haraguchi, Tsuyoshi

    2018-01-01

    Although the application of LiDAR has made significant contributions to archaeology, LiDAR only provides a synchronic view of the current topography. An important challenge for researchers is to extract diachronic information over typically extensive LiDAR-surveyed areas in an efficient manner. By applying an architectural chronology obtained from intensive excavations at the site center and by complementing it with surface collection and test excavations in peripheral zones, we analyze LiDAR data over an area of 470 km2 to trace social changes through time in the Ceibal region, Guatemala, of the Maya lowlands. We refine estimates of structure counts and populations by applying commission and omission error rates calculated from the results of ground-truthing. Although the results of our study need to be tested and refined with additional research in the future, they provide an initial understanding of social processes over a wide area. Ceibal appears to have served as the only ceremonial complex in the region during the transition to sedentism at the beginning of the Middle Preclassic period (c. 1000 BC). As a more sedentary way of life was accepted during the late part of the Middle Preclassic period and the initial Late Preclassic period (600–300 BC), more ceremonial assemblages were constructed outside the Ceibal center, possibly symbolizing the local groups’ claim to surrounding agricultural lands. From the middle Late Preclassic to the initial Early Classic period (300 BC-AD 300), a significant number of pyramidal complexes were probably built. Their high concentration in the Ceibal center probably reflects increasing political centralization. After a demographic decline during the rest of the Early Classic period, the population in the Ceibal region reached the highest level during the Late and Terminal Classic periods, when dynastic rule was well established (AD 600–950). PMID:29466384

  18. Archaeological application of airborne LiDAR to examine social changes in the Ceibal region of the Maya lowlands.

    Directory of Open Access Journals (Sweden)

    Takeshi Inomata

    Full Text Available Although the application of LiDAR has made significant contributions to archaeology, LiDAR only provides a synchronic view of the current topography. An important challenge for researchers is to extract diachronic information over typically extensive LiDAR-surveyed areas in an efficient manner. By applying an architectural chronology obtained from intensive excavations at the site center and by complementing it with surface collection and test excavations in peripheral zones, we analyze LiDAR data over an area of 470 km2 to trace social changes through time in the Ceibal region, Guatemala, of the Maya lowlands. We refine estimates of structure counts and populations by applying commission and omission error rates calculated from the results of ground-truthing. Although the results of our study need to be tested and refined with additional research in the future, they provide an initial understanding of social processes over a wide area. Ceibal appears to have served as the only ceremonial complex in the region during the transition to sedentism at the beginning of the Middle Preclassic period (c. 1000 BC. As a more sedentary way of life was accepted during the late part of the Middle Preclassic period and the initial Late Preclassic period (600-300 BC, more ceremonial assemblages were constructed outside the Ceibal center, possibly symbolizing the local groups' claim to surrounding agricultural lands. From the middle Late Preclassic to the initial Early Classic period (300 BC-AD 300, a significant number of pyramidal complexes were probably built. Their high concentration in the Ceibal center probably reflects increasing political centralization. After a demographic decline during the rest of the Early Classic period, the population in the Ceibal region reached the highest level during the Late and Terminal Classic periods, when dynastic rule was well established (AD 600-950.

  19. Archaeological application of airborne LiDAR to examine social changes in the Ceibal region of the Maya lowlands.

    Science.gov (United States)

    Inomata, Takeshi; Triadan, Daniela; Pinzón, Flory; Burham, Melissa; Ranchos, José Luis; Aoyama, Kazuo; Haraguchi, Tsuyoshi

    2018-01-01

    Although the application of LiDAR has made significant contributions to archaeology, LiDAR only provides a synchronic view of the current topography. An important challenge for researchers is to extract diachronic information over typically extensive LiDAR-surveyed areas in an efficient manner. By applying an architectural chronology obtained from intensive excavations at the site center and by complementing it with surface collection and test excavations in peripheral zones, we analyze LiDAR data over an area of 470 km2 to trace social changes through time in the Ceibal region, Guatemala, of the Maya lowlands. We refine estimates of structure counts and populations by applying commission and omission error rates calculated from the results of ground-truthing. Although the results of our study need to be tested and refined with additional research in the future, they provide an initial understanding of social processes over a wide area. Ceibal appears to have served as the only ceremonial complex in the region during the transition to sedentism at the beginning of the Middle Preclassic period (c. 1000 BC). As a more sedentary way of life was accepted during the late part of the Middle Preclassic period and the initial Late Preclassic period (600-300 BC), more ceremonial assemblages were constructed outside the Ceibal center, possibly symbolizing the local groups' claim to surrounding agricultural lands. From the middle Late Preclassic to the initial Early Classic period (300 BC-AD 300), a significant number of pyramidal complexes were probably built. Their high concentration in the Ceibal center probably reflects increasing political centralization. After a demographic decline during the rest of the Early Classic period, the population in the Ceibal region reached the highest level during the Late and Terminal Classic periods, when dynastic rule was well established (AD 600-950).

  20. The Nordic Prudent Diet Reduces Risk of Cognitive Decline in the Swedish Older Adults: A Population-Based Cohort Study

    Directory of Open Access Journals (Sweden)

    Behnaz Shakersain

    2018-02-01

    Full Text Available Appropriate dietary pattern for preserving cognitive function in northern Europe remains unknown. We aimed to identify a Nordic dietary pattern index associated with slower cognitive decline compared to the Mediterranean-DASH Intervention for Neurodegenerative Delay, Mediterranean Diet, Dietary Approaches to Stop Hypertension, and Baltic Sea Diet indices. A total of 2223 dementia-free adults aged ≥60 were followed for 6 years. Mini-Mental State Examination was administrated at baseline and follow-ups. Dietary intake was assessed by 98-item food frequency questionnaire, and the Nordic Prudent Dietary Pattern (NPDP was identified. Data were analysed using mixed-effects and parametric survival models and receiver operating characteristic curves with adjustment for potential confounders. Moderate (β = 0.139, 95% CI 0.077−0.201 and high adherence (β = 0.238, 95% CI 0.175−0.300 to NPDP were associated with less cognitive decline compared to other four indices. High adherence to NPDP was also associated with the lowest risk of MMSE decline to ≤24 (HR = 0.176, 95% CI 0.080−0.386 and had the greatest ability to predict such decline (area under the curve = 0.70. Moderate-to-high adherence to the NPDP may predict a better-preserved cognitive function among older adults in Nordic countries. Regional dietary habits should be considered in developing dietary guidelines for the prevention of cognitive impairment and dementia.

  1. The Nordic Prudent Diet Reduces Risk of Cognitive Decline in the Swedish Older Adults: A Population-Based Cohort Study.

    Science.gov (United States)

    Shakersain, Behnaz; Rizzuto, Debora; Larsson, Susanna C; Faxén-Irving, Gerd; Fratiglioni, Laura; Xu, Wei-Li

    2018-02-17

    Appropriate dietary pattern for preserving cognitive function in northern Europe remains unknown. We aimed to identify a Nordic dietary pattern index associated with slower cognitive decline compared to the Mediterranean-DASH Intervention for Neurodegenerative Delay, Mediterranean Diet, Dietary Approaches to Stop Hypertension, and Baltic Sea Diet indices. A total of 2223 dementia-free adults aged ≥60 were followed for 6 years. Mini-Mental State Examination was administrated at baseline and follow-ups. Dietary intake was assessed by 98-item food frequency questionnaire, and the Nordic Prudent Dietary Pattern (NPDP) was identified. Data were analysed using mixed-effects and parametric survival models and receiver operating characteristic curves with adjustment for potential confounders. Moderate (β = 0.139, 95% CI 0.077-0.201) and high adherence (β = 0.238, 95% CI 0.175-0.300) to NPDP were associated with less cognitive decline compared to other four indices. High adherence to NPDP was also associated with the lowest risk of MMSE decline to ≤24 (HR = 0.176, 95% CI 0.080-0.386) and had the greatest ability to predict such decline (area under the curve = 0.70). Moderate-to-high adherence to the NPDP may predict a better-preserved cognitive function among older adults in Nordic countries. Regional dietary habits should be considered in developing dietary guidelines for the prevention of cognitive impairment and dementia.

  2. Culturable bacterial populations associated with ectomycorrhizae of Norway spruce stands with different degrees of decline in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Avidano, L.; Rinaldi, M.; Gindro, R.; Cudlín, Pavel; Martinotti, M G.; Fracchia, L.

    2010-01-01

    Roč. 56, č. 1 (2010), s. 52-64 ISSN 0008-4166 Institutional research plan: CEZ:AV0Z60870520 Keywords : Ectomycorrhizae * Norway spruce * forest decline Subject RIV: EE - Microbiology, Virology Impact factor: 1.235, year: 2010

  3. The catastrophic decline of the Sumatran rhino (Dicerorhinus sumatrensis harrissoni in Sabah: Historic exploitation, reduced female reproductive performance and population viability

    Directory of Open Access Journals (Sweden)

    P. Kretzschmar

    2016-04-01

    Full Text Available The reasons for catastrophic declines of Sumatran rhinos are far from clear and data necessary to improve decisions for conservation management are often lacking. We reviewed literature and assembled a comprehensive data set on surveys of the Sumatran rhino subspecies (Dicerorhinus sumatrensis harrissoni in the Malaysian state of Sabah on Borneo to chart the historical development of the population in Sabah and its exploitation until the present day. We fitted resource selection functions to identify habitat features preferred by a remnant population of rhinos living in the Tabin Wildlife Reserve in Sabah, and ran a series of population viability analyses (PVAs to extract the key demographic parameters most likely to affect population dynamics. We show that as preferred habitat, the individuals in the reserve were most likely encountered in elevated areas away from roads, in close distance to mud-volcanoes, with a low presence of human trespassers and a wallow on site, and within a neighbourhood of dense forest and grassland patches preferably on Fluvisols and Acrisols. Our population viability analyses identified the percentage of breeding females and female lifetime reproductive period as the crucial parameters driving population dynamics, in combination with total protection even moderate improvements could elevate population viability substantially. The analysis also indicates that unrestrained hunting between 1930 and 1950 drastically reduced the historical rhino population in Sabah and that the remnant population could be rescued by combining the effort of total protection and stimulation of breeding activity. Based on our results, we recommend to translocate isolated reproductively healthy individuals to protected locations and to undertake measures to maximise conceptions, or running state-of-the-art reproductive management with assisted reproduction techniques. Our study demonstrates that a judicious combination of techniques can do

  4. Figurative Language on Maya Angelou selected Poetries

    Directory of Open Access Journals (Sweden)

    Risma Hayani

    2016-12-01

    Full Text Available This study aimed to find out the kinds of figurative language in the five selected poetries of Maya Angelou, the titles are: Alone, Caged Bird, Old Folks Laugh, Phenomenal Woman, Still I Rise. The focus of this study is figurative language which involves: Metaphor, Personification, Hyperbole, Simile, Metonymy, Synecdoche, Irony, Antithesis, Symbolism, and Paradox. Qualitative approach with design of content analysis was used in this study. The researcher acted as the main instrument since she was the one who analyzed the figurative language. Moreover checklist was also used to support her data collection. The data was analyzed through three stages; 1. Data reduction, 2. Data representation, 3. Conclusion. The result of her study showed there were 40 sentences that containing figurative language in five selected poetries of Maya Angelou. They were; Metaphor (13 sentences, Personification (9 sentences, Hyperbole (1 sentence, Simile (8 sentences, Synecdoche (1 sentence, Antithesis (1 sentence, Symbolism (5 sentences, and Paradox (2 sentences. The researcher conclude, if the figurative language used by Angelou to compare, or even symbolize the sentences to bring the meaning come up with beautiful language. Mostly of her poetries told about her experience in the past that rooted to history of the discrimination of American-African.

  5. Levels of persistent organic pollutants in breast milk of Maya women in Yucatan, Mexico.

    Science.gov (United States)

    Polanco Rodríguez, Ángel G; Inmaculada Riba López, M; Angel DelValls Casillas, T; León, Jesús Alfredo Araujo; Anjan Kumar Prusty, B; Álvarez Cervera, Fernando J

    2017-02-01

    In this study, 24 breast milk samples, obtained from rural Maya women, from municipalities of Yucatan, Mexico, were analyzed for organochlorine pesticide (OCP) residues by gas chromatography. Recent studies have shown that Maya communities have a poor perception about the proper usage and handling of OCP. The karstic soil in this area has a high vulnerability to groundwater pollution by the use of OCP in agriculture and livestock activities. The impact of the ecosystem on human health is much more critical due to the prevailing poverty and a very low educational level of these communities. About 30% of the Maya population consumes water directly from contaminated wells and sinkholes, resulting in a chronic exposure to OCP. The samples served to identify and quantify high levels of OCP residues (18.43 mg/kg of heptachlor epoxide and 1.92 mg/kg of endrin in the metropolitan zone; 2.10 mg/kg of dieldrin, 0.117 mg/kg of endosulfan II, 0.103 mg/kg of heptachlor, 0.178 mg/kg of endrin, and 0.127 mg/kg of endrin aldehyde in the main agricultural zone and on the west coast). The detected levels of OCP residues are a major concern and represent a potential risk to women and children in the region. This could be associated with the high rates of cervical uterine and breast cancer mortality in Yucatan. Thus, regulations on the usage of OCP and their enforcement are necessary, and it is important to establish a yearly monitoring program for OCP residues in breast milk and groundwater, as well as to implement health promotion programs for women in particular and the general population in general.

  6. Fe K-edge XANES of Maya blue pigment

    Science.gov (United States)

    Río, M. Sánchez del; Sodo, A.; Eeckhout, S. G.; Neisius, T.; Martinetto, P.; Dooryhée, E.; Reyes-Valerio, C.

    2005-08-01

    The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the "Maya blue" pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si8(Mg2Al2)O20(OH)2(OH2)4.4H2O and an organic colourant (indigo: C16H10N2O2), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue.

  7. Fe K-edge XANES of Maya blue pigment

    International Nuclear Information System (INIS)

    Rio, M. Sanchez del; Sodo, A.; Eeckhout, S.G.; Neisius, T.; Martinetto, P.; Dooryhee, E.; Reyes-Valerio, C.

    2005-01-01

    The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the 'Maya blue' pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si 8 (Mg 2 Al 2 )O 20 (OH) 2 (OH 2 ) 4 .4H 2 O and an organic colourant (indigo: C 16 H 10 N 2 O 2 ), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue

  8. Agua y Enfermedad Entre Algunos Grupos Mayas Durante La Colonia.

    Directory of Open Access Journals (Sweden)

    Tañía Héléne Campos Thomas.

    2006-12-01

    Full Text Available Along history, The mexican People ―for all the different ethnic groups in the country― has had water in high regard in their religious corpus, either in the symbolic way or the religious level. As evidence of this we can mention the cults to Tlaloc in mesoamerica and chak in the maya region, and the numerous depictions produced by chronicle writers as well as the ones found in the maya codices containing rites and giving close records of the beliefs in which water had a fundamental role. Similarly, the maya culture nowadays preserves that same close relation between water and health-illness. This article is a first investigative look into this subject intendingto restrict time and objectives and also with the aim of recording the way in which some maya ethnic groups were related to water during the colonial period. despite the colonial period was the historical framework imposed as the limit to the present paper, it has been inevitable to make reference to customs and activities of contemporary maya groups.

  9. The impact of birth weight on the level of lung function and lung function decline in the general adult population. The Inter99 study

    DEFF Research Database (Denmark)

    Baumann, Sophie; Godtfredsen, Nina Skavlan; Lange, Peter

    2015-01-01

    BACKGROUND: Previous studies have reported an association between low birth weight and low adult lung function, but findings have not been consistent. The aim of this study was to investigate whether birth weight is associated with both the level and the decline in adult lung function in general...... population. METHODS: The Danish Inter99 study is a population-based intervention study in adults aged 30-60 years, providing information on birth weight and lung function on 4428 participants. Of these, 2931 participants performed spirometry at baseline and at five-year follow-up. Multiple linear regression...... models were used to examine the association between birth weight and forced expiratory volume in first second (FEV1) and forced vital capacity (FVC) and age-related decline in these variables. Analyses were conducted stepwise including sex, age, adult height, abdominal circumference, birth height, mother...

  10. Brain Amyloid Deposition and Longitudinal Cognitive Decline in Nondemented Older Subjects: Results from a Multi-Ethnic Population.

    Directory of Open Access Journals (Sweden)

    Yian Gu

    Full Text Available We aimed to whether the abnormally high amyloid-β (Aβ level in the brain among apparently healthy elders is related with subtle cognitive deficits and/or accelerated cognitive decline.A total of 116 dementia-free participants (mean age 84.5 years of the Washington Heights Inwood Columbia Aging Project completed 18F-Florbetaben PET imaging. Positive or negative cerebral Aβ deposition was assessed visually. Quantitative cerebral Aβ burden was calculated as the standardized uptake value ratio in pre-established regions of interest using cerebellar cortex as the reference region. Cognition was determined using a neuropsychological battery and selected tests scores were combined into four composite scores (memory, language, executive/speed, and visuospatial using exploratory factor analysis. We examined the relationship between cerebral Aβ level and longitudinal cognition change up to 20 years before the PET scan using latent growth curve models, controlling for age, education, ethnicity, and Apolipoprotein E (APOE genotype.Positive reading of Aβ was found in 41 of 116 (35% individuals. Cognitive scores at scan time was not related with Aβ. All cognitive scores declined over time. Aβ positive reading (B = -0.034, p = 0.02 and higher Aβ burden in temporal region (B = -0.080, p = 0.02 were associated with faster decline in executive/speed. Stratified analyses showed that higher Aβ deposition was associated with faster longitudinal declines in mean cognition, language, and executive/speed in African-Americans or in APOE ε4 carriers, and with faster memory decline in APOE ε4 carriers. The associations remained significant after excluding mild cognitive impairment participants.High Aβ deposition in healthy elders was associated with decline in executive/speed in the decade before neuroimaging, and the association was observed primarily in African-Americans and APOE ε4 carriers. Our results suggest that measuring cerebral Aβ may give us

  11. Genetic structure of populations of whale sharks among ocean basins and evidence for their historic rise and recent decline

    KAUST Repository

    Vignaud, Thomas M.; Maynard, Jeffrey Allen; Leblois, Raphaë l; Meekan, Mark G.; Vá zquez-Juá rez, Ricardo; Ramí rez-Mací as, Dení ; Pierce, Simon J.; Rowat, David; Berumen, Michael L.; Beeravolu, Champak R.; Baksay, Sandra; Planes, Serge

    2014-01-01

    This study presents genetic evidence that whale sharks, Rhincodon typus, are comprised of at least two populations that rarely mix and is the first to document a population expansion. Relatively high genetic structure is found when comparing sharks

  12. Declining prevalence of pulmonary paragonimiasis following treatment & community education in a remote tribal population of Arunachal Pradesh, India.

    Science.gov (United States)

    Narain, Kanwar; Devi, K Rekha; Bhattacharya, S; Negmu, K; Rajguru, S K; Mahanta, Jagadish

    2015-05-01

    In India, human pulmonary paragonimiasis is an important public health problem in the northeastern (NE) region. In 2005 we reported a hyperendemic focus of paragonimiasis in a remote tribal village in the hills of Changlang district in Arunachal Pradesh. The community was made aware of the disease and all active cases were treated. This study was aimed to assess the decline in the prevelance of paragonimiasis in the same area after a re-survey done in 2011 after a gap of six years. Re-surveys were carried to determine the reduction in the prevalence of paragonimiasis. Community education was given to the villagers to raise their awareness about paragonimiasis. A total of 624 individuals including 301 children (age 15 yr) were included in the study. Sputum and stool samples were examined for eggs of lung flukes. Serum samples were screened for IgG antibodies against lung fluke antigen by ELISA. A significant (P 31 yr, the decline in prevalence was from 15.3 to 3.7 per cent. Gender-wise analysis revealed that the decline in ELISA positivity was similar in both genders and fell down from 33.9 to 11.5 per cent in males and from 29.8 to 10.7 per cent in females. Similarly, there was a significant decline rate in egg positivity also. The strategy of hotspot targeted active paragonimiasis case detection and treatment of infected cases together with community education appears to be feasible methods to achieve control of paragonimiasis in this region.

  13. How to Cheat in Maya 2012 Tools and Techniques for Character Animation

    CERN Document Server

    Luhta, Eric

    2011-01-01

    The Maya guide for animators, How to Cheat in Maya 2012 presents everything you need to know about character animation in Maya. Fully updated for the latest revision of Maya, this book provides you with complete, step-by-step walkthroughs of essential animation techniques to increase your efficiency and speed. This is an animator's workflow in book form, written by professional animators-not a software book with a few animation pointers thrown in. In addition to all the gold-mine coverage and interviews with expert animators from the previous edition, How to Cheat in Maya 2012 also features a

  14. Compositional attribution of non-provenienced Maya polychrome vessels

    International Nuclear Information System (INIS)

    Bishop, R.L.; Harbottle, G.; Reents, D.J.; Sayre, E.V.; van Zelst, L.

    1983-01-01

    Procedures and a few of the results of the Maya ceramic project are discussed from the perspective of non-provenienced vessel attribution ranging from site specific through a more inferential level to the rather hypothetical. The examples presented serve to illustrate the manner in which compositional and stylistic covariation are viewed in an investigation of Maya Ceramic art. The large data base from neutron activation analysis including archaeologically recovered pottery as well as the stylistically and iconographically elaborate vessels requires continued refinement in our methods of statistical analysis along with gaining a greater understanding of the sources of ceramic compositional variation in the Maya area. The mutually beneficial collaboration between science, art, and archaeology are emphasized

  15. Stability and instability on Maya Lowlands tropical hillslope soils

    Science.gov (United States)

    Beach, Timothy; Luzzadder-Beach, Sheryl; Cook, Duncan; Krause, Samantha; Doyle, Colin; Eshleman, Sara; Wells, Greta; Dunning, Nicholas; Brennan, Michael L.; Brokaw, Nicholas; Cortes-Rincon, Marisol; Hammond, Gail; Terry, Richard; Trein, Debora; Ward, Sheila

    2018-03-01

    Substantial lake core and other evidence shows accelerated soil erosion occurred in the Maya Lowlands of Central America over ancient Maya history from 3000 to 1000 years ago. But we have little evidence of the wider network of the sources and sinks of that eroded sediment cascade. This study begins to solve the mystery of missing soil with new research and a synthesis of existing studies of tropical forest soils along slopes in NW Belize. The research aim is to understand soil formation, long-term human impacts on slopes, and slope stability over time, and explore ecological implications. We studied soils on seven slopes in tropical forest areas that have experienced intensive ancient human impacts and those with little ancient impacts. All of our soil catenas, except for one deforested from old growth two years before, contain evidence for about 1000 years of stable, tropical forest cover since Maya abandonment. We characterized the physical, chemical, and taxonomic characteristics of soils at crest-shoulder, backslopes, footslopes, and depression locations, analyzing typical soil parameters, chemical elements, and carbon isotopes (δ13C) in dated and undated sequences. Four footslopes or depressions in areas of high ancient occupation preserved evidence of buried, clay-textured soils covered by coarser sediment dating from the Maya Classic period. Three footslopes from areas with scant evidence of ancient occupation had little discernable deposition. These findings add to a growing corpus of soil toposequences with similar facies changes in footslopes and depressions that date to the Maya period. Using major elemental concentrations across a range of catenas, we derived a measure (Ca + Mg) / (Al + Fe + Mn) of the relative contributions of autochthonous and allochthonous materials and the relative age of soil catenas. We found very low ratios in clearly older, buried soils in footslopes and depressions and on slopes that had not undergone ancient Maya erosion. We

  16. Compositional attribution of non-provenienced Maya polychrome vessels

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, R.L.; Harbottle, G.; Reents, D.J.; Sayre, E.V.; van Zelst, L.

    1983-01-01

    Procedures and a few of the results of the Maya ceramic project are discussed from the perspective of non-provenienced vessel attribution ranging from site specific through a more inferential level to the rather hypothetical. The examples presented serve to illustrate the manner in which compositional and stylistic covariation are viewed in an investigation of Maya Ceramic art. The large data base from neutron activation analysis including archaeologically recovered pottery as well as the stylistically and iconographically elaborate vessels requires continued refinement in our methods of statistical analysis along with gaining a greater understanding of the sources of ceramic compositional variation in the Maya area. The mutually beneficial collaboration between science, art, and archaeology are emphasized.

  17. A spatial analysis of population dynamics and climate change in Africa: potential vulnerability hot spots emerge where precipitation declines and demographic pressures coincide

    Science.gov (United States)

    López-Carr, David; Pricope, Narcisa G.; Aukema, Juliann E.; Jankowska, Marta M.; Funk, Christopher C.; Husak, Gregory J.; Michaelsen, Joel C.

    2014-01-01

    We present an integrative measure of exposure and sensitivity components of vulnerability to climatic and demographic change for the African continent in order to identify “hot spots” of high potential population vulnerability. Getis-Ord Gi* spatial clustering analyses reveal statistically significant locations of spatio-temporal precipitation decline coinciding with high population density and increase. Statistically significant areas are evident, particularly across central, southern, and eastern Africa. The highly populated Lake Victoria basin emerges as a particularly salient hot spot. People located in the regions highlighted in this analysis suffer exceptionally high exposure to negative climate change impacts (as populations increase on lands with decreasing rainfall). Results may help inform further hot spot mapping and related research on demographic vulnerabilities to climate change. Results may also inform more suitable geographical targeting of policy interventions across the continent.

  18. Failure to Respond to Food Resource Decline Has Catastrophic Consequences for Koalas in a High-Density Population in Southern Australia.

    Directory of Open Access Journals (Sweden)

    Desley A Whisson

    Full Text Available Understanding the ability of koalas to respond to changes in their environment is critical for conservation of the species and their habitat. We monitored the behavioural response of koalas to declining food resources in manna gum (Eucalyptus viminalis woodland at Cape Otway, Victoria, Australia, from September 2011 to November 2013. Over this period, koala population density increased from 10.1 to 18.4 koalas.ha-1. As a result of the high browsing pressure of this population, manna gum canopy condition declined with 71.4% manna gum being completely or highly defoliated in September 2013. Despite declining food resources, radio collared koalas (N = 30 exhibited high fidelity to small ranges (0.4-1.2 ha. When trees became severely defoliated in September 2013, koalas moved relatively short distances from their former ranges (mean predicted change in range centroid = 144 m and remained in areas of 0.9 to 1.0 ha. This was despite the high connectivity of most manna gum woodland, and close proximity of the study site (< 3 km to the contiguous mixed forest of the Great Otway National Park. Limited movement had catastrophic consequences for koalas with 71% (15/21 of radio collared koalas dying from starvation or being euthanased due to their poor condition between September and November 2013.

  19. Effects of Cougar Predation and Nutrition on Mule Deer Population Declines in the Intermountain Province of the Columbia Basin, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wielgus, Robert B.; Shipley, Lisa

    2002-07-01

    Construction of the Grand Coulee and Chief Joseph dams has resulted in inundation and loss of 29,125 total habitat units for mule deer and irrigation agriculture in many parts the Intermountain Province (IM) of the Columbia Basin. Mule deer in the Shrub-Steppe are ranked high priority target species for mitigation and management and are declining in most portions of the subbasins of the IM. Reasons for the decline are unknown but believed to be related to habitat changes resulting from dams and irrigation agriculture. White-tailed deer are not ranked as target species and are believed to be increasing throughout the basin because of habitat changes brought about by the dams and irrigation agriculture. Recent research (1997-2000) in the NE IM and adjacent Canadian portions of the Columbia Basin (conducted by this author and funded by the Columbia Basin Fish & Wildlife Compensation Program B.C.), suggest that the increasing white-tailed deer populations (because of dams and irrigation agriculture) are resulting in increased predation by cougars on mule deer (apparent competition or alternate prey hypothesis). The apparent competition hypothesis predicts that as alternate prey (white-tailed deer) densities increase, so do densities of predators, resulting in increased incidental predation on sympatric native prey (mule deer). Apparent competition can result in population declines and even extirpation of native prey in some cases. Such a phenomenon may account for declines of mule deer in the IM and throughout arid and semi-arid West where irrigation agriculture is practiced. We will test the apparent competition hypothesis by conducting a controlled, replicated ''press'' experiment in at least 2 treatment and 2 control areas of the IM subbasins by reducing densities of white-tailed deer and observing any changes in cougar predation on mule deer. Deer densities will be monitored by WADFW personnel using annual aerial surveys and/or other trend

  20. Effects of Cougar Predation and Nutrition on Mule Deer Population Declines in the IM Province of the Columbia Basin, Annual Report 2002-2003.

    Energy Technology Data Exchange (ETDEWEB)

    Wielgus, Robert; Shipley, Lisa; Myers, Woodrow

    2003-09-01

    Construction of the Grand Coulee and Chief Joseph dams has resulted in inundation and loss of 29,125 total habitat units for mule deer and irrigation agriculture in many parts the Intermountain Province (IM) of the Columbia Basin. Mule deer in the Shrub-Steppe are ranked high priority target species for mitigation and management and are declining in most portions of the sub basins of the IM. Reasons for the decline are unknown but believed to be related to habitat changes resulting from dams and irrigation agriculture. White-tailed deer are believed to be increasing throughout the basin because of habitat changes brought about by the dams and irrigation agriculture. Recent research (1997-2000) in the NE IM and adjacent Canadian portions of the Columbia Basin (conducted by this author and funded by the Columbia Basin Fish & Wildlife Compensation Program B.C.), suggest that the increasing white-tailed deer populations (because of dams and irrigation agriculture) are resulting in increased predation by cougars on mule deer (apparent competition or alternate prey hypothesis). The apparent competition hypothesis predicts that as alternate prey (white-tailed deer) densities increase, so do densities of predators, resulting in increased incidental predation on sympatric native prey (mule deer). Apparent competition can result in population declines and even extirpation of native prey in some cases. Such a phenomenon may account for declines of mule deer in the IM and throughout arid and semi-arid West where irrigation agriculture is practiced. We will test the apparent competition hypothesis by conducting a controlled, replicated 'press' experiment in at least 2 treatment and 2 control areas of the IM sub basins by reducing densities of white-tailed deer and observing any changes in cougar predation on mule deer. Deer densities will be monitored by WADFW personnel using annual aerial surveys and/or other trend indices. Predation rates and population growth rates

  1. Predisposition to bark beetle attack by root herbivores and associated pathogens: Roles in forest decline, gap formation, and persistence of endemic bark beetle populations

    DEFF Research Database (Denmark)

    Aukema, Brian H.; Zhu, Jun; Møller, Jesper

    2010-01-01

    , however, due to the requirement of long-term monitoring and high degrees of spatial and temporal covariance. We censused more than 2700 trees annually over 7 years, and at the end of 17 years, in a mature red pine plantation. Trees were measured for the presence of bark beetles and wood borers that breed...... within the primary stem, root weevils that breed in root collars, and bark beetles that breed in basal stems. We quantify the sequence of events that drive this decline syndrome, with the primary emergent pattern being an interaction between below- and above-ground herbivores and their fungal symbionts......, and elevated temperature slightly accentuates this effect. New gaps can arise from such trees as they subsequently become epicenters for the full complex of organisms associated with this decline, but this is not common. As Ips populations rise, there is some element of positive feedback...

  2. APROXIMACIONES A LA ETNOMICOLOGÍA MAYA

    Directory of Open Access Journals (Sweden)

    Felipe Ruan-Soto

    2015-12-01

    Full Text Available Los pueblos mayas habitan una región biológicamente megadiversa y tradicionalmente hacen uso diversificado de sus recursos. Desde la etnomicología —disciplina que estudia la relación entre grupos humanos y hongos— se cuenta con amplia evidencia del conocimiento y uso de estos organismos entre tales grupos étnicos. Tal evidencia se extiende hasta tiempos prehispánicos con hongos piedra, códices y crónicas. Actualmente se tiene conocimiento de 134 especies comestibles —ya sean para autoconsumo o venta— y alrededor de 40 hongos medicinales en la región. Asociados con estos usos, existen conocimientos morfológicos, fenológicos, ecológicos y culinarios de los hongos, así como desarrollados esquemas de nomenclatura y clasificación, el reconocimiento de 36 especies consideradas tóxicas y la presencia de hongos en diferentes narrativas. APPROACHES TO MAYAN ETHNOMYCOLOGY The Mayan peoples inhabit a biologically megadiverse region and have traditionally made a diversified use of their resources. Ethnomycology —the discipline that studies the relationship between human groups and mushrooms— provides extensive evidence of the knowledge these ethnic groups have of mushrooms and their use. Evidence can be traced back to pre-Hispanic times with mushrooms carved in stone and their presence in codices and chronicles. In the region, 134 edible species —either for consumption or for trade— are currently known, as well as about 40 medicinal mushrooms. Morphological, phenological, ecological and culinary data as well as nomenclature and classification schemes are associated with these uses. The identification of 36 species considered toxic and the presence of mushrooms in different narratives is also part of this body of knowledge.

  3. Declining Brown-headed Cowbird (Molothrus ater populations are associated with landscape-specific reductions in brood parasitism and increases in songbird productivity.

    Directory of Open Access Journals (Sweden)

    W Andrew Cox

    Full Text Available Many songbird species have experienced significant population declines, partly because of brood parasitism by the Brown-headed Cowbird (Molothrus ater, which is positively associated with increasing landscape forest cover in the midwestern United States. However, cowbirds are also experiencing long-term population declines, which should reduce parasitism pressure and thus increase productivity of host species. We used 20 years of nest monitoring data from five sites in Missouri across a gradient of landscape forest cover to assess temporal trends in the rate and intensity of brood parasitism for Acadian Flycatchers (Empidonax virescens, Indigo Buntings (Passerina cyanea, and Northern Cardinals (Cardinalis cardinalis. We evaluated whether there were concomitant changes in fledging brood size, nest survival, a combination of the two metrics (i.e., host young produced per nest attempt, and whether such changes were more substantial with decreasing landscape forest cover. Parasitism rates and intensities declined substantially during 1991-2010. Fledging brood size and nest survival rates were positively associated with landscape forest cover, confirming the fragmentation hypothesis for Midwest forest birds. Declining parasitism rates were associated with increased fledging brood sizes, with more pronounced increases as landscape forest cover decreased. Nest survival increased insubstantially across time during laying and incubation, but not during the nestling stage. The best predictor of nest survival was parasitism status, with parasitized nests surviving at lower rates than unparasitized nests. Overall, productivity increased during 1991-2010, with more pronounced increases associated with lower levels of landscape forest cover. The negative effects of cowbirds on nest survival in addition to fledging brood size in less forested landscapes suggest that cowbirds may be a primary cause of forest fragmentation effects on songbird productivity in the

  4. Are toxins from harmful algae a factor involved in the decline of harbour seal populations in Scotland?

    OpenAIRE

    Jensen, Silje-Kristin

    2015-01-01

    Firstly this study builds on the investigation initiated by Hall and Frame (2010), which found that Scottish harbour seals were exposed to domoic acid (DA), a potent natural neurotoxin produced by phytoplankton. Using the same sample collection technique to gather urine and faecal material from various populations around Scotland with differing population trajectories (Lonergan et al., 2007), the objective was to investigate not only exposure to DA, but also other groups of ...

  5. Development of sedentary communities in the Maya lowlands: coexisting mobile groups and public ceremonies at Ceibal, Guatemala.

    Science.gov (United States)

    Inomata, Takeshi; MacLellan, Jessica; Triadan, Daniela; Munson, Jessica; Burham, Melissa; Aoyama, Kazuo; Nasu, Hiroo; Pinzón, Flory; Yonenobu, Hitoshi

    2015-04-07

    Our archaeological investigations at Ceibal, a lowland Maya site located in the Pasión region, documented that a formal ceremonial complex was built around 950 B.C. at the onset of the Middle Preclassic period, when ceramics began to be used in the Maya lowlands. Our refined chronology allowed us to trace the subsequent social changes in a resolution that had not been possible before. Many residents of Ceibal appear to have remained relatively mobile during the following centuries, living in ephemeral post-in-ground structures and frequently changing their residential localities. In other parts of the Pasión region, there may have existed more mobile populations who maintained the traditional lifestyle of the preceramic period. Although the emerging elite of Ceibal began to live in a substantial residential complex by 700 B.C., advanced sedentism with durable residences rebuilt in the same locations and burials placed under house floors was not adopted in most residential areas until 500 B.C., and did not become common until 300 B.C. or the Late Preclassic period. During the Middle Preclassic period, substantial formal ceremonial complexes appear to have been built only at a small number of important communities in the Maya lowlands, and groups with different levels of sedentism probably gathered for their constructions and for public rituals held in them. These collaborative activities likely played a central role in socially integrating diverse groups with different lifestyles and, eventually, in developing fully established sedentary communities.

  6. Family and the Bildungsroman Tradition in Maya Angelou's I Know ...

    African Journals Online (AJOL)

    The paper examines family and the bildungsroman process in Maya Angelou's I know Why the Caged Bird Sings and Chimamanda Adichie's Purple Hibiscus. The study is carried out mainly through Sigmund Freud's Psychoanalytical critical theory. The paper notes that the nuclear family's responsibility at grooming the ...

  7. Politics in the Western Maya Region (II: Emblem Glyphs

    Directory of Open Access Journals (Sweden)

    Péter Bíró

    2012-01-01

    Full Text Available In a series of articles I reflect on the use of various expressions which are connected to what we call the political in the inscriptions of the Classic Maya Western Region. These words express ideas and concepts which help to understand the intricate details of the interactions between the political entities and their internal organisations in the Classic Maya Lowlands. In this article I investigate the meaning of emblem glyphs. I suggest that originally they were toponyms but later on they became titles of origin which indicated descendance from a common origin place.En una serie de artículos investigo el uso de varias palabras en las inscripciones mayas de la época Clásica de la Región Occidental que se conectan con lo que nosotros llamamos "política". Estas palabras expresan ideas y conceptos que ayudan a entender los matices de las relaciones entre las entidades políticas de las Tierras Bajas Mayas y su organización interna. En este artículo investigo el significado de los glifos emblema. Propongo que originalmente fueron topónimos y después llegaron a ser títulos de origen que indicaron descendencia común de un lugar original.

  8. A draft de novo genome assembly for the northern bobwhite (Colinus virginianus reveals evidence for a rapid decline in effective population size beginning in the Late Pleistocene.

    Directory of Open Access Journals (Sweden)

    Yvette A Halley

    Full Text Available Wild populations of northern bobwhites (Colinus virginianus; hereafter bobwhite have declined across nearly all of their U.S. range, and despite their importance as an experimental wildlife model for ecotoxicology studies, no bobwhite draft genome assembly currently exists. Herein, we present a bobwhite draft de novo genome assembly with annotation, comparative analyses including genome-wide analyses of divergence with the chicken (Gallus gallus and zebra finch (Taeniopygia guttata genomes, and coalescent modeling to reconstruct the demographic history of the bobwhite for comparison to other birds currently in decline (i.e., scarlet macaw; Ara macao. More than 90% of the assembled bobwhite genome was captured within 14,000 unique genes and proteins. Bobwhite analyses of divergence with the chicken and zebra finch genomes revealed many extremely conserved gene sequences, and evidence for lineage-specific divergence of noncoding regions. Coalescent models for reconstructing the demographic history of the bobwhite and the scarlet macaw provided evidence for population bottlenecks which were temporally coincident with human colonization of the New World, the late Pleistocene collapse of the megafauna, and the last glacial maximum. Demographic trends predicted for the bobwhite and the scarlet macaw also were concordant with how opposing natural selection strategies (i.e., skewness in the r-/K-selection continuum would be expected to shape genome diversity and the effective population sizes in these species, which is directly relevant to future conservation efforts.

  9. Combining the Rowland Universal Dementia Assessment Scale and the Informant Questionnaire on Cognitive Decline in the Elderly to Improve Detection of Dementia in an Arabic-Speaking Population

    DEFF Research Database (Denmark)

    Nielsen, T. Rune; Phung, Thien Kieu Thi; Chaaya, Monique

    2016-01-01

    BACKGROUND/AIMS: The aim of this study was to assess whether combining the Rowland Universal Dementia Assessment Scale (RUDAS) and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) could improve diagnostic accuracy when screening for dementia in an Arabic-speaking population...... a significantly better area under the curve value compared to the RUDAS used alone. The 'weighted sum' method and the 'and' rule had the highest specificity, while the 'or' rule had the best sensitivity. CONCLUSION: Harnessing the RUDAS and IQCODE increased diagnostic accuracy when screening for dementia...

  10. Imaginando a los mayas de hoy: autorrepresentación y política

    Directory of Open Access Journals (Sweden)

    Ana Rosa Duarte Duarte

    2008-01-01

    Full Text Available En este artículo se analiza el proceso de representación y autorrepresentación de los mayas de Yucatán en Sáastal: Los hijos de la Santa Gracia, una video-ficción de cincuenta y cinco minutos. En Sáastal se pone en escena el drama de la vida cotidiana de una familia maya de acuerdo con la imaginación, tanto de los mayas que participamos en la producción como de los no mayas. Se analiza cómo la convivencia de la cultura maya con las diversas políticas civilizatorias, entre éstas, las de desarrollo, modernización y globalización, han influido en el imaginario de los mayas contemporáneos. Esta convivencia entre dos culturas ha llevado a los mayas a adoptar "identidades suaves", que les permiten actuar de acuerdo con las circunstancias. En Sáastal, los mayas "performamos", recreamos e instrumentalizamos la cultura y convertimos en ficticias nuestras propias identidades.In this article I analyze the processes of representation and self-representation of the Yucatec Maya in Sáastal: The Children of the Sacred Grace, a 55-minute video-fiction. Sáastal presents a dramatic account of the everyday life of a Yucatec Maya family as imagined both by the Maya and non-Maya participating in the production. I examine how this imaginary is influenced by the coexistence of the Mayan culture with the diverse civilizatory politics, such as the politics of development, modernization, and globalization. it is argued that this coexistence has led us, the Yucatec Maya, to adopt "soft identities" which allow us to act according to the circumstances. In Sáastal we therefore perform, recreate and instrumentalize our culture and, in this way, convert our own identities into fictions.

  11. Age-related olfactory decline is associated with the BDNF val66met polymorphism: evidence from a population-based study

    Directory of Open Access Journals (Sweden)

    Margareta Hedner

    2010-06-01

    Full Text Available The present study investigates the effect of the brain-derived neurotrophic factor (BDNF val66met polymorphism on change in olfactory function in a large scale, longitudinal population-based sample (n=836. The subjects were tested on a 13 item force-choice odor identification test on two test occasions over a 5-year-interval. Sex, education, health-related factors, and semantic ability were controlled for in the statistical analyses. Results showed an interaction effect of age and BDNF val66met on olfactory change, such that the magnitude of olfactory decline in the older age cohort (70-90 years old at baseline was larger for the val homozygote carriers than for the met carriers. The older met carriers did not display larger age-related decline in olfactory function compared to the younger group. The BDNF val66met polymorphism did not affect the rate of decline in the younger age cohort (45-65 years. The findings are discussed in the light of the proposed roles of BDNF in neural development and maintenance.

  12. Trends in Modifiable Risk Factors Are Associated With Declining Incidence of Hospitalized and Nonhospitalized Acute Coronary Heart Disease in a Population.

    Science.gov (United States)

    Mannsverk, Jan; Wilsgaard, Tom; Mathiesen, Ellisiv B; Løchen, Maja-Lisa; Rasmussen, Knut; Thelle, Dag S; Njølstad, Inger; Hopstock, Laila Arnesdatter; Bønaa, Kaare Harald

    2016-01-05

    Few studies have used individual person data to study whether contemporary trends in the incidence of coronary heart disease are associated with changes in modifiable coronary risk factors. We identified 29 582 healthy men and women ≥25 years of age who participated in 3 population surveys conducted between 1994 and 2008 in Tromsø, Norway. Age- and sex-adjusted incidence rates were calculated for coronary heart disease overall, out-of-hospital sudden death, and hospitalized ST-segment-elevation and non-ST-segment-elevation myocardial infarction. We measured coronary risk factors at each survey and estimated the relationship between changes in risk factors and changes in incidence trends. A total of 1845 participants had an incident acute coronary heart disease event during 375 064 person-years of follow-up from 1994 to 2010. The age- and sex-adjusted incidence of total coronary heart disease decreased by 3% (95% confidence interval, 2.0-4.0; Pcoronary risk factors accounted for 66% (95% confidence interval, 48-97; Pcoronary heart disease. Favorable changes in cholesterol contributed 32% to the decline, whereas blood pressure, smoking, and physical activity each contributed 14%, 13%, and 9%, respectively. We observed a substantial decline in the incidence of coronary heart disease that was driven by reductions in out-of-hospital sudden death and hospitalized ST-segment-elevation myocardial infarction. Changes in modifiable coronary risk factors accounted for 66% of the decline in coronary heart disease events. © 2015 American Heart Association, Inc.

  13. Digital Preservation of Ancient Maya Cave Architecture: Recent Field Efforts in Quintana Roo, Mexico

    Science.gov (United States)

    Rissolo, D.; Lo, E.; Hess, M. R.; Meyer, D. E.; Amador, F. E.

    2017-08-01

    The presence of ancient Maya shrines in caves serves as unequivocal evidence for the ritual appropriation of these subterranean spaces and their significance with respect to Maya religious practice. Detailed study of the miniature masonry temples and altar features in the caves of Quintana Roo, Mexico reveals a strong stylistic and likely functional correspondence between these structures and their terrestrial counterparts at Postclassic sites. The Proyecto Arquitectura Subterranea de Quintana Roo (coordinated by the Center of Interdisciplinary Science for Art, Architecture, and Archaeology, or CISA3, at the University of California, San Diego and in collaboration with the Instituto Nacional de Antropologia e Historia in Mexico) is conducting a survey and program of digital documentation of both the pristine and impacted cave shrines of the region. Once an area is developed and populated, and access is opened to caves containing ancient architectural features, they are soon vandalized - often resulting in the complete obliteration of these rare miniature buildings and their diagnostic architectural elements. This emergent situation necessitates the use of rapid reality-capture tools; however, the physical challenges of working in caves requires researchers of adapt increasingly common architectural documentation methodologies to more adverse field conditions.

  14. Endothelial Nitric Oxide Synthase Haplotypes Are Associated with Preeclampsia in Maya Mestizo Women

    Science.gov (United States)

    Díaz-Olguín, Lizbeth; Coral-Vázquez, Ramón Mauricio; Canto-Cetina, Thelma; Canizales-Quinteros, Samuel; Ramírez Regalado, Belem; Fernández, Genny; Canto, Patricia

    2011-01-01

    Preeclampsia is a specific disease of pregnancy and believed to have a genetic component. The aim of this study was to investigate if three polymorphisms in eNOS or their haplotypes are associated with preeclampsia in Maya mestizo women. A case-control study was performed where 127 preeclamptic patients and 263 controls were included. Genotyped and haplotypes for the -768T→C, intron 4 variants, Glu298Asp of eNOS were determined by PCR and real-time PCR allelic discrimination. Logistic regression analysis with adjustment for age and body mass index (BMI) was used to test for associations between genotype and preeclampsia under recessive, codominant and dominant models. Pairwise linkage disequilibrium between single nucleotide polymorphisms was calculated by direct correlation r2, and haplotype analysis was conducted. Women homozygous for the Asp298 allele showed an association of preeclampsia. In addition, analysis of the haplotype frequencies revealed that the -786C-4b-Asp298 haplotype was significantly more frequent in preeclamptic patients than in controls (0.143 vs. 0.041, respectively; OR = 3.01; 95% CI = 1.74–5.23; P = 2.9 × 10−4). Despite the Asp298 genotype in a recessive model associated with the presence of preeclampsia in Maya mestizo women, we believe that in this population the -786C-4b-Asp298 haplotype is a better genetic marker. PMID:21897002

  15. Tratamiento del cuerpo y control social entre los mayas itzaes, siglos XVII-XVIII

    Directory of Open Access Journals (Sweden)

    Caso Barrera, Laura

    2015-12-01

    Full Text Available In many societies the human body is considered as a cosmological model and therefore of society. In the case of the Maya Itza we know that the human body is a reference to their territorial, social and religious organization. In this paper we analyze the importance of the human body as a symbolic model, focusing on aspects of Itza religion and rituals, related to the transformation and modification of the human body. We will analyze how Itza society controlled a population with the ability of transfiguration.En diversas sociedades el cuerpo humano se ha concebido como un modelo cosmológico y por lo tanto de la sociedad. En el caso de los mayas itzaes sabemos que el cuerpo humano es un referente para la organización territorial, social y religiosa. En este trabajo se analiza la importancia del cuerpo humano como modelo simbólico, centrándonos en aspectos de la religión y rituales itzaes relacionados con la transformación y modificación del cuerpo humano en el período colonial. Se examina el control que ejerció la sociedad itzá con respecto a una población con la capacidad de transfiguración.

  16. DIGITAL PRESERVATION OF ANCIENT MAYA CAVE ARCHITECTURE: RECENT FIELD EFFORTS IN QUINTANA ROO, MEXICO

    Directory of Open Access Journals (Sweden)

    D. Rissolo

    2017-08-01

    Full Text Available The presence of ancient Maya shrines in caves serves as unequivocal evidence for the ritual appropriation of these subterranean spaces and their significance with respect to Maya religious practice. Detailed study of the miniature masonry temples and altar features in the caves of Quintana Roo, Mexico reveals a strong stylistic and likely functional correspondence between these structures and their terrestrial counterparts at Postclassic sites. The Proyecto Arquitectura Subterranea de Quintana Roo (coordinated by the Center of Interdisciplinary Science for Art, Architecture, and Archaeology, or CISA3, at the University of California, San Diego and in collaboration with the Instituto Nacional de Antropologia e Historia in Mexico is conducting a survey and program of digital documentation of both the pristine and impacted cave shrines of the region. Once an area is developed and populated, and access is opened to caves containing ancient architectural features, they are soon vandalized – often resulting in the complete obliteration of these rare miniature buildings and their diagnostic architectural elements. This emergent situation necessitates the use of rapid reality-capture tools; however, the physical challenges of working in caves requires researchers of adapt increasingly common architectural documentation methodologies to more adverse field conditions.

  17. Fe K-edge XANES of Maya blue pigment

    Energy Technology Data Exchange (ETDEWEB)

    Rio, M. Sanchez del [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France)]. E-mail: srio@esrf.fr; Sodo, A. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Eeckhout, S.G. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Neisius, T. [ESRF, Experiments Division, B.P. 220, F-38043, Grenoble Cedex (France); Martinetto, P. [Laboratoire de Cristallographie, CNRS, Grenoble B.P. 166, F-38042, Grenoble Cedex 09 (France); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, Grenoble B.P. 166, F-38042, Grenoble Cedex 09 (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico)

    2005-08-15

    The utilization of techniques used in Materials Science for the characterization of artefacts of interest for cultural heritage is getting more and more attention nowadays. One of the products of the ancient Maya chemistry is the 'Maya blue' pigment, made with natural indigo and palygorskite. This pigment is different from any other pigment used in other parts of the world. It is durable and acid-resistant, and still keeps many secrets to scientists even though it has been studied for more than 50 years. Although the pigment is basically made of palygorskite Si{sub 8}(Mg{sub 2}Al{sub 2})O{sub 20}(OH){sub 2}(OH{sub 2}){sub 4}.4H{sub 2}O and an organic colourant (indigo: C{sub 16}H{sub 10}N{sub 2}O{sub 2}), a number of other compounds have been found in previous studies on archaeological samples, like other clays and minerals, iron nanoparticles, iron oxides, impurities of transition metals (Cr, Mn, Ti, V), etc. We measured at the ESRF ID26 beamline the Fe K-edge XANES spectra of the blue pigment in ancient samples. They are compared to XANES spectra of Maya blue samples synthesized under controlled conditions, and iron oxides usually employed as pigments (hematite and goethite). Our results show that the iron found in ancient Maya blue pigment is related to the Fe exchanged in the palygorskite clay. We did not find iron in metallic form or goethite in archaeological Maya blue.

  18. Further evidence of large-scale population decline and range contraction of the little owl Athene noctua in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Chrenková, M.; Dobrý, M.; Šálek, Martin

    2017-01-01

    Roč. 66, č. 2 (2017), s. 106-116 ISSN 0139-7893 Institutional support: RVO:68081766 Keywords : farmland birds * population trend * distribution * breeding places * agricultural buildings * conservation measures Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 0.739, year: 2016

  19. Brief Report: Anal Cancer in the HIV-Positive Population: Slowly Declining Incidence After a Decade of cART

    NARCIS (Netherlands)

    Richel, Olivier; van der Zee, Ramon P.; Smit, Colette; de Vries, Henry J. C.; Prins, Jan M.

    2015-01-01

    We surveyed trends in incidence (1995-2012) and risk factors for anal cancer in the Dutch HIV-positive population. After an initial increase with a peak incidence in 2005-2006 of 114 [95% confidence interval (CI): 74 to 169] in all HIV+ patients and 168 (95% CI: 103 to 259) in HIV+ men who have sex

  20. Improved analysis of long-term monitoring data demonstrates marked regional declines of bat populations in the eastern United States

    Science.gov (United States)

    Thomas E. Ingersoll; Brent J. Sewall; Sybill K. Amelon

    2013-01-01

    Bats are diverse and ecologically important, but are also subject to a suite of severe threats. Evidence for localized bat mortality from these threats is well-documented in some cases, but long-term changes in regional populations of bats remain poorly understood. Bat hibernation surveys provide an opportunity to improve understanding, but analysis is complicated by...

  1. PROTOPLANETARY DISK MASSES IN IC348: A RAPID DECLINE IN THE POPULATION OF SMALL DUST GRAINS AFTER 1 Myr

    International Nuclear Information System (INIS)

    Lee, Nicholas; Williams, Jonathan P.; Cieza, Lucas A.

    2011-01-01

    We present a 1.3 mm continuum survey of protoplanetary disks in the 2-3 Myr old cluster, IC348, with the Submillimeter Array. We observed 85 young stellar objects and detected 10 with 1.3 mm fluxes greater than 2 mJy. The brightest source is a young embedded protostar driving a molecular outflow. The other nine detections are dusty disks around optically visible stars. Our millimeter flux measurements translate into total disk masses ranging from 2 to 6 Jupiter masses. Each detected disk has strong mid-infrared emission in excess of the stellar photosphere and has Hα equivalent widths larger than the average in the cluster and indicative of ongoing gas accretion. The disk mass distribution, however, is shifted by about a factor of 20 to lower masses, compared to that in the ∼1 Myr old Taurus and Ophiuchus regions. These observations reveal the rapid decline in the number of small dust grains in disks with time and probably their concomitant growth beyond millimeter sizes. Moreover, if IC348 is to form planets in the same proportion as detected in the field, these faint millimeter detections may represent the best candidates in the cluster to study the progression from planetesimals to planets.

  2. Long-term decline of the populations of Fucales (Cystoseira spp. and Sargassum spp.) in the Albères coast (France, North-western Mediterranean).

    Science.gov (United States)

    Thibaut, Thierry; Pinedo, Susana; Torras, Xavier; Ballesteros, Enric

    2005-12-01

    Only five of fourteen species of Fucales reported at the end of the XIXth century are currently present in the Albères Coast (France, NW Mediterranean). According to historical data there has been a steady decrease of all the populations since the 1940s. Seven taxa now extinct (Cystoseira crinita, Cystoseira barbata, Cystoseira foeniculacea f. tenuiramosa, Cystoseira spinosa, Cystoseira spinosa var. compressa, Sargassum hornschuchii and Sargassum vulgare) were considered frequent and some of them were the dominant and engineering species in several phytobenthic assemblages. Moreover, only one of the five species left, shows no signs of regression (Cystoseira compressa), two are considered as rare (Cystoseira caespitosa, Cystoseira zosteroides), and one is very rare (Cystoseira elegans). Cystoseira mediterranea, a species that was reported to make a continuous belt along the shores of the Albères coast, has almost disappeared from some areas. Overgrazing by sea urchins, outcompetition by mussels, habitat destruction, scientific research sampling and, probably, human trampling and chemical pollution are to be blamed for the decline of populations thriving in shallow waters. Deep-water species have been affected by an increase in water turbidity and, probably, chemical pollution and direct plant destruction attributed to net fishing. If degradation of the environmental conditions continues, the remaining Cystoseira species will face a most unwelcome prospect. Even after the removal of the causes that led to its die-off, natural restoration of extinct species seems not to be possible because the decline has also affected populations from nearby areas and zygotes are unable to disperse over long distances. Urgent management actions have to be designed in order to improve the current situation of the populations of Fucales in the Albères coast.

  3. Local Recurrence in Women With Stage I Breast Cancer: Declining Rates Over Time in a Large, Population-Based Cohort

    Energy Technology Data Exchange (ETDEWEB)

    Canavan, Joycelin, E-mail: canavanjoycelin@gmail.com [Radiation Therapy Program and Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver Island Centre, University of British Columbia, Victoria, British Columbia (Canada); Truong, Pauline T.; Smith, Sally L. [Radiation Therapy Program and Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver Island Centre, University of British Columbia, Victoria, British Columbia (Canada); Lu, Linghong; Lesperance, Mary [Department of Mathematics and Statistics, University of Victoria, British Columbia (Canada); Olivotto, Ivo A. [Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary (Canada)

    2014-01-01

    increased. These changes contributed to the observed declining LR rates among patients treated with breast-conserving therapy.

  4. Local Recurrence in Women With Stage I Breast Cancer: Declining Rates Over Time in a Large, Population-Based Cohort

    International Nuclear Information System (INIS)

    Canavan, Joycelin; Truong, Pauline T.; Smith, Sally L.; Lu, Linghong; Lesperance, Mary; Olivotto, Ivo A.

    2014-01-01

    increased. These changes contributed to the observed declining LR rates among patients treated with breast-conserving therapy

  5. Religión, fiestas y centros ceremoniales mayas de la Cruz Parlante

    Directory of Open Access Journals (Sweden)

    Manuel Buenrostro Alba

    2015-07-01

    Full Text Available En el trabajo se describe el principal santo de los mayas de Quintana Roo, la Cruz Parlante, así como los centros ceremoniales y las fiestas tradicionales relacionadas con esta advocación. Se incluyen datos etnográficos que describen el contexto en el que se centra el estudio. La Cruz Parlante permite a los mayas de Quintana Roo seguir existiendo y los protege, pero para ello debe estar custodiada por los propios mayas.

  6. Ethnomedical research and review of Q'eqchi Maya women's reproductive health in the Lake Izabal region of Guatemala: Past, present and future prospects.

    Science.gov (United States)

    Michel, Joanna L; Caceres, Armando; Mahady, Gail B

    2016-02-03

    In Central America, most Maya women use ethnomedicines for all aspects of their reproductive cycle including menstruation, pregnancy and menopause. However, very few of these plants have been documented, collected and tested in appropriate pharmacological assays to determine possible safety and efficacy. The aim of this work was to provide an overview of information on the ethnomedical uses, ethnopharmacology, chemistry and pharmacological research for medicinal plants used for women's reproductive health in Guatemala, with a special emphasis on the Q'eqchi Maya of the Lake Izabal region, to demonstrate therapeutic potential and support future research in the field. Reviews of the ethnobotanical, ethnomedical and ethnopharmacological literature were performed for 30 plants collected in the Lake Izabal region of Guatemala and used by the Q'eqchi Maya for treatment of reproductive health issues were performed up to and including July 2015 using multiple databases, library searches for abstracts, books, dissertations, and websites. Review of the published research confirms that many of the plants used by Q'eqchi Maya women for the management of reproductive health issues have pharmacological activities, including analgesic, anti-inflammatory, estrogenic, progestagenic and/or serotonergic effects, that support the use of these plants and provide plausible mechanisms of action for their traditional uses. Furthermore, a new serotonin agonist, 9, 10-methylenedioxy-5, 6-Z-fadyenolide was isolated, thereby demonstrating an untapped potential for drug discovery. However, to date much of the pharmacological assays have been in vitro only, and few in vivo studies have been performed. Considering the large percentage of the Maya population in Guatemala that use traditional medicines, there remains a significant lack of pharmacological and toxicological data for these plants. Future research should focus on the safety and efficacy of medicinal plants using in vivo preclinical

  7. Los mayas del altiplano: supervivencia indígena en Chiapas y Guatemala

    OpenAIRE

    Lovell, W. George

    2002-01-01

    En el contexto americano, pocos grupos indígenas han demostrado la capacidad de sobrevivir a lo largo de la historia como los mayas del altiplano. Hoy día en Chiapas existen más de un millón de indígenas mayas, un número que asciende a cinco o seis millones en el caso de Guatemala. Los pueblos mayas han respondido a la invasión y a la dominación para conservar elementos importantes de su cultura. Este artículo discute las formas en que los mayas del altiplano se han adaptado para sobrevivir a...

  8. Spatio-temporal variation in age structure and abundance of the endangered snail kite: Pooling across regions masks a declining and aging population

    Science.gov (United States)

    Reichert, Brian E.; Kendall, William L.; Fletcher, Robert J.; Kitchens, Wiley M.

    2016-01-01

    While variation in age structure over time and space has long been considered important for population dynamics and conservation, reliable estimates of such spatio-temporal variation in age structure have been elusive for wild vertebrate populations. This limitation has arisen because of problems of imperfect detection, the potential for temporary emigration impacting assessments of age structure, and limited information on age. However, identifying patterns in age structure is important for making reliable predictions of both short- and long-term dynamics of populations of conservation concern. Using a multistate superpopulation estimator, we estimated region-specific abundance and age structure (the proportion of individuals within each age class) of a highly endangered population of snail kites for two separate regions in Florida over 17 years (1997–2013). We find that in the southern region of the snail kite—a region known to be critical for the long-term persistence of the species—the population has declined significantly since 1997, and during this time, it has increasingly become dominated by older snail kites (> 12 years old). In contrast, in the northern region—a region historically thought to serve primarily as drought refugia—the population has increased significantly since 2007 and age structure is more evenly distributed among age classes. Given that snail kites show senescence at approximately 13 years of age, where individuals suffer higher mortality rates and lower breeding rates, these results reveal an alarming trend for the southern region. Our work illustrates the importance of accounting for spatial structure when assessing changes in abundance and age distribution and the need for monitoring of age structure in imperiled species.

  9. Declining trend in the incidence of biopsy-verified coeliac disease in the adult population of Finland, 2005-2014.

    Science.gov (United States)

    Virta, L J; Saarinen, M M; Kolho, K-L

    2017-12-01

    The frequency of coeliac disease (CD) has been on the rise over the past decades, especially in Western Europe, but current trends are unclear. To research the recent temporal changes in the incidence of adult, biopsy-verified coeliac disease and dermatitis herpetiformis (DH) in Finland, a country with a high frequency of coeliac disease. All coeliac disease and DH cases diagnosed at age 20-79 years during 2005-2014 were retrieved from a nationwide database documenting all applicants for monthly compensation to cover the extra cost of maintaining a gluten-free diet. This benefit is granted on the basis of histology, not socioeconomic status. Temporal trends in the annual incidences were estimated using Poisson regression analyses. The total incidence of coeliac disease decreased from 33/100 000 during the years 2005-2006 to 29/100 000 during 2013-2014. The mean annual incidence of coeliac disease was nearly twice as high among women as among men, 42 vs 22 per 100 000, respectively. For middle- and old-aged women, the average rate of decrease in incidence was 4.8% (95% CI 3.9-5.7) per year and for men 3.0% (1.8-4.1) (P for linear trend adults, the rate of change remained low and nonsignificant throughout the period 2005-2014. Although the awareness of coeliac disease has increased during the past decades, the incidence of biopsy-verified diagnoses is not increasing, which suggests that exposure to yet unidentified triggering factors for coeliac disease has plateaued among the Finnish adult population. © 2017 John Wiley & Sons Ltd.

  10. Microanalysis study of archaeological mural samples containing Maya blue pigment

    International Nuclear Information System (INIS)

    Sanchez del Rio, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhee, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

    2004-01-01

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used

  11. PROBİYOTİK MAYA : SACCHAROMYCES BOULARDİİ

    OpenAIRE

    Alkan, Rezan

    2013-01-01

    Probiyotikler uygun miktarlarda kullanıldığında konakçı sağlığı üzerinde yararları olan, bağırsakta canlı kalabilen ,sindirime dirençli bakteri ve maya gibi canlı mikroorganizmalar olarak tanımlanmaktadır. Saccharomyces boulardii  patojen olmayan bir maya olup, tedavi edici olarak kullanılmaktadır. Kontrollü olarak yapılan klinik çalışmalarda S.boulardii’nin çeşitli bağırsak hastalıklarının önlenmesi ve ...

  12. Microanalysis study of archaeological mural samples containing Maya blue pigment

    Science.gov (United States)

    Sánchez del Río, M.; Martinetto, P.; Somogyi, A.; Reyes-Valerio, C.; Dooryhée, E.; Peltier, N.; Alianelli, L.; Moignard, B.; Pichon, L.; Calligaro, T.; Dran, J.-C.

    2004-10-01

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

  13. Microanalysis study of archaeological mural samples containing Maya blue pigment

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, M. [ESRF, BP220, F-38043 Grenoble (France)]. E-mail: srio@esrf.fr; Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Somogyi, A. [ESRF, BP220, F-38043 Grenoble (France); Reyes-Valerio, C. [INAH, Mexico DF (Mexico); Dooryhee, E. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Peltier, N. [Laboratoire de Cristallographie, CNRS, BP166 F-30842 Grenoble (France); Alianelli, L. [INFM-OGG c/o ESRF, BP220, F-38043 Grenoble Cedex (France); Moignard, B. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Pichon, L. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Calligaro, T. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France); Dran, J.-C. [C2RMF, 6 Rue des Pyramides, F-75041 Paris Cedex 01 (France)

    2004-10-08

    Elemental analysis by X-ray fluorescence and particle induced X-ray emission is applied to the study of several Mesoamerican mural samples containing blue pigments. The most characteristic blue pigment is Maya blue, a very stable organo-clay complex original from Maya culture and widely used in murals, pottery and sculptures in a vast region of Mesoamerica during the pre-hispanic time (from VIII century) and during the colonization until 1580. The mural samples come from six different archaeological sites (four pre-hispanic and two from XVI century colonial convents). The correlation between the presence of some elements and the pigment colour is discussed. From the comparative study of the elemental concentration, some conclusions are drawn on the nature of the pigments and the technology used.

  14. Quantifying the contribution of statins to the decline in population mean cholesterol by socioeconomic group in England 1991 - 2012: a modelling study.

    Directory of Open Access Journals (Sweden)

    Chris Kypridemos

    Full Text Available Serum total cholesterol is one of the major targets for cardiovascular disease prevention. Statins are effective for cholesterol control in individual patients. At the population level, however, their contribution to total cholesterol decline remains unclear. The aim of this study was to quantify the contribution of statins to the observed fall in population mean cholesterol levels in England over the past two decades, and explore any differences between socioeconomic groups.This is a modelling study based on data from the Health Survey for England. We analysed changes in observed mean total cholesterol levels in the adult England population between 1991-92 (baseline and 2011-12. We then compared the observed changes with a counterfactual 'no statins' scenario, where the impact of statins on population total cholesterol was estimated and removed. We estimated uncertainty intervals (UI using Monte Carlo simulation, where confidence intervals (CI were impractical. In 2011-12, 13.2% (95% CI: 12.5-14.0% of the English adult population used statins at least once per week, compared with 1991-92 when the proportion was just 0.5% (95% CI: 0.3-1.0%. Between 1991-92 and 2011-12, mean total cholesterol declined from 5.86 mmol/L (95% CI: 5.82-5.90 to 5.17 mmol/L (95% CI: 5.14-5.20. For 2011-12, mean total cholesterol was lower in more deprived groups. In our 'no statins' scenario we predicted a mean total cholesterol of 5.36 mmol/L (95% CI: 5.33-5.40 for 2011-12. Statins were responsible for approximately 33.7% (95% UI: 28.9-38.8% of the total cholesterol reduction since 1991-92. The statin contribution to cholesterol reduction was greater among the more deprived groups of women, while showing little socio-economic gradient among men.Our model suggests that statins explained around a third of the substantial falls in total cholesterol observed in England since 1991. Approximately two thirds of the cholesterol decrease can reasonably be attributed non

  15. El cemento y el concreto de los mayas

    Directory of Open Access Journals (Sweden)

    Horacio Ramírez de Alba

    1999-01-01

    Full Text Available Se realiza un estudio técnico sobre los materiales utilizados por los constructores mayas, quienes lograron obras cuyos vestigios maravillan hoy al mundo. Se presentan los resultados obtenidos al realizar pruebas físicas y químicas en muestras de estucos, morteros y concretos provenientes de zonas arqueológicas, principalmente Palenque y Yaxchilán, en el estado de Chiapas, México.

  16. El cemento y el concreto de los mayas

    OpenAIRE

    Horacio Ramírez de Alba; Ramiro Pérez Campos; Heriberto Díaz Coutiño

    1999-01-01

    Se realiza un estudio técnico sobre los materiales utilizados por los constructores mayas, quienes lograron obras cuyos vestigios maravillan hoy al mundo. Se presentan los resultados obtenidos al realizar pruebas físicas y químicas en muestras de estucos, morteros y concretos provenientes de zonas arqueológicas, principalmente Palenque y Yaxchilán, en el estado de Chiapas, México.

  17. Guatemala conservation concession for the Maya Biosphere Reserve

    OpenAIRE

    Conservation International

    2007-01-01

    Metadata only record The national government of Guatemala has issued timber concessions to local communities within its 2 million hectare Maya Biosphere Reserve. Working under this framework, CI is proposing a conservation concession contract with two communities. The concessions would be designed to pay salaries for conservation managers, to invest in projects such as guiding tourists to nearby archaeological sites and to provide community services such as education and health care, in ex...

  18. What We Think We Know About Maya Mathematics and Astronomy

    Science.gov (United States)

    Van Stone, M.

    2016-01-01

    In most cultures, mathematics and astronomy are obscure and arcane. Not so to the ancient Maya. Despite what we consider technological “deficiencies”—they lacked both metal tools and the wheel—their public inscriptions paid uniquely sophisticated attention to these sciences. At any given monument, fully half the text is devoted to situating events in time, particularly specifying the precise number of days between events, whether historical or mythological. Often these intervals have numerological significance, and many are precise multiples of the periodicities of heavenly bodies. The Maya apparently were fully aware of the exact length of the tropical year, the sidereal year, the cycles of Venus, and eclipses; and there is evidence that they even celebrated events reflecting the 26,000-year precession cycle. However, Maya illuminati had an agenda quite alien to our way of thinking. Clues to their knowledge are arcane, rare, and often difficult for us to recognize with eyes clouded by our modern worldview. The body of work left to us consists of just a few tantalizing sherds of a once-rich and diverse astromythological tradition. Moreover, there was no single pan-Mayan mythos. An astronomical alignment seen repeatedly in one city will be completely absent in others. Each city-state emphasized specific and often unique features, and they often contradict one another. But we soldier on. The diversity we find so frustrating is simply the fine structure of their worldview. Intellectual historians have for too long been, like Procrustes, trying to force all Maya science and religion into a single universal straitjacket.

  19. Resistencia indígena y discursos racistas: una lectura biopolítica de los mayas yucatecos

    Directory of Open Access Journals (Sweden)

    Izaskun Álvarez Cuartero

    2012-06-01

    Full Text Available In this article I propose to analyse the history of Yucatec Maya people from a biopolitical perspective. I study two periods of great importance in Mayan history: first, during the colonial period, the politics of population control and the peculiar geography of Yucatan guide us to explain how the colony was settled there; while the second part discusses the lack of instability of Mayan Indians during Independence, the indigenous resistance that will eventually lead to the 1847 Caste War and its consequence: the sale of Mayan Indians as slaves to Cuba as an alternative to eliminate Indian rebels and to create an imagined nation of Yucatan.

  20. Combined hydrogen and carbon isotopes of plant waxes as an indicator of drought impacts on ancient Maya agriculture

    Science.gov (United States)

    Douglas, P. M.; Pagani, M.; Eglinton, T. I.; Brenner, M.; Hodell, D. A.; Curtis, J. H.

    2012-12-01

    There is increasing evidence suggesting that a series of droughts in the Yucatan Peninsula coincided with the Terminal Classic decline of the Classic Maya civilization (ca. 1250 to 1000 years BP). However, there is little evidence directly linking climatic change and changes in human activities in this region. In this study we combine plant-wax δD, δ13C, and Δ14C analyses in two lake sediment cores from southeastern Mexico and northern Guatemala to develop coupled records of hydroclimate variability and human-driven vegetation change. Plant-wax specific Δ14C ages indicate a large input of pre-aged plant waxes into lake sediment. Comparison of plant-wax δD records with other regional hydroclimate proxy records suggest that plant-wax ages are evenly distributed around plant-wax radiocarbon ages, and that applying an age model based on plant-wax radiocarbon ages is appropriate for these lake sediments. We evaluate how differences in plant-wax age distributions influence stable isotope records to assess the age uncertainty associated with records of climate and vegetation change derived from plant-wax stable isotopes. In this low-elevation tropical environment plant-wax δ13C is largely controlled by the relative abundance of C3 and C4 plants. The ancient Maya practiced widespread maize (C4) agriculture and strongly influenced regional C3-C4 vegetation dynamics. Under natural conditions C4 plant coverage and plant-wax δ13C would tend to co-vary positively since C4 plants are well adapted for dry conditions. Under ancient Maya land-use, however, this relationship is likely to be decoupled, since drought would have disrupted C4 agriculture. Combined analysis of plant-wax δD and δ13C from both lakes indicates increasingly divergent trends following ca. 3500 years BP, around the onset of widespread ancient Maya agriculture. After this time high plant-wax δD values tend to correspond with low plant-wax δ13C values and vice versa. This pattern is consistent with

  1. Analysis of obsidian from moho cay, belize: new evidence on classic maya trade routes.

    Science.gov (United States)

    Healy, P F; McKillop, H I; Walsh, B

    1984-07-27

    Trace element analysis of obsidian artifacts from Moho Cay, Belize, reveals that the obsidian derives primarily from the El Chayal outcrop in highland Guatemala and not from the Ixtepeque source. This is contrary to the widely accepted obsidian trade route model for Classic Maya civilization and suggests that Classic Maya obsidian trade was a more complex economic phenomenon than has been recognized.

  2. Representing Mayas : Indigenous Authorities and the Local Politics of Identity in Guatemala

    NARCIS (Netherlands)

    Rasch, E.D.

    2008-01-01

    Against the backdrop of emerging indigenous movements in Latin America, the Maya Movement appeared as a political actor in the 1980s, bringing “the Indian Question” to the fore in Guatemalan politics. Rejecting racism and assimilationalist State policies, the Maya Movement seeks to recapture

  3. 77 FR 53959 - Culturally Significant Object Imported for Exhibition Determinations: “Dancing Into Dreams, Maya...

    Science.gov (United States)

    2012-09-04

    ... DEPARTMENT OF STATE [Public Notice 8009] Culturally Significant Object Imported for Exhibition Determinations: ``Dancing Into Dreams, Maya Vases From the IK'Kingdom'' SUMMARY: Notice is hereby given of the... exhibition ``Dancing Into Dreams, Maya Vases from the IK'Kingdom,'' imported from abroad for temporary...

  4. Maya medicine in the biological gaze: bioprospecting research as herbal fetishism.

    Science.gov (United States)

    Nigh, Ronald

    2002-06-01

    The relationship of human societies to territory and natural resources is being drastically altered by a series of global agreements concerning trade, intellectual property, and the conservation and use of genetic resources. Through a characteristic style of collective appropriation of their tropical ecosystems, Maya societies have created local institutions for governing access to their common resources. However, new mechanisms of global governance require access to Maya biodiversity for world commercial interests. The Chiapas Highland Maya already face this prospect in the International Cooperative Biodiversity Group drug discovery project, which proposes to use Maya medical knowledge to screen plants for potential pharmaceuticals. The ethnobiological focus of the project emphasizes the naturalistic aspects of Maya medicine, primarily the use of herbal remedies. This biological gaze decontextualizes the situated knowledge of Maya healers, ignoring the cultural context in which they create and apply that knowledge. The search for raw materials for the production of universal medical technology results in symbolic violence to the cultural logic of Maya peoples. Only the full recognition of Maya peoples' collective rights to territory and respect for their local common-resource institutions will provide ultimate protection for their cultural and natural patrimony.

  5. Economic Stratification Differentiates Home Gardens in the Maya Village of Pomuch, Mexico

    NARCIS (Netherlands)

    Poot-Pool, W.S.; Wal, van der J.C.; Flores-Guido, S.; Pat-Fernández, J.M.; Esparza-Olguín, L.

    2012-01-01

    Economic Stratification Differentiates Home Gardens in the Maya Village of Pomuch, Mexico. In this paper, we analyze if economic stratification of peasant families in a Maya village in the Yucatán Peninsula of Mexico influences species composition and structure of home gardens. Our general

  6. Print Knowledge in Yucatec Maya-Spanish Bilingual Children: An Initial Inquiry

    Science.gov (United States)

    Bengochea, Alain; Justice, Laura M.; Hijlkema, Maria J.

    2017-01-01

    This study serves as an initial inquiry regarding the early print knowledge of emergent bilingual preschool-age children living in an Indigenous community in Mexico. In this research, we examine various dimensions of print knowledge with Yucatec Maya-Spanish bilingual children for whom one of their languages (Yucatec Maya) is seldom seen in print…

  7. Language Revitalisation from the Ground Up: Promoting Yucatec Maya on Facebook

    Science.gov (United States)

    Cru, Josep

    2015-01-01

    This paper looks at current grassroots efforts to revitalise Yucatec Maya, an indigenous language of Mexico, in social media and more specifically on Facebook. In contrast to the limitations of institutional language promotion, the inclusion of Maya on Facebook shows the possibilities that social networks offer not only for actual use of…

  8. MaritimeMaya2011: The Costa Escondida Project: Exploring the Hidden World of the Maritime Maya on the Yucatan Peninsula between 20110509 and 20110531

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The northeast tip of the Yucatan Peninsula is a largely unexplored coastline where ancient Maya traders traveled in massive dugout canoes filled with goods from...

  9. Predictors of short-term mortality, cognitive and physical decline in older adults in northwest Russia: a population-based prospective cohort study.

    Science.gov (United States)

    Turusheva, Anna; Frolova, Elena; Hegendoerfer, Eralda; Degryse, Jean-Marie

    2017-08-01

    The classical phenotype, accumulated deficit model and self-report approach of frailty were found not useful in older adults in northwest Russia. More research is needed to identify predictors of adverse outcomes in this population. The aim of this study is to identify predictors of mortality, autonomy and cognitive decline in a population that is characterized by a high cardiovascular morbidity and mortality rate. A population-based prospective cohort study of 611 community-dwelling individuals 65+. Anthropometry, medical history nutritional status were recorded. An evaluation of cognitive, physical and autonomy function, spirometry, and laboratory tests were performed. The total follow-up was 5 years. Multiple imputation, backward stepwise Cox regression analysis, C-statistic, risk reclassification analysis and the bootstrapping techniques were used to analyze the data. We found that the combination of increasing age, male sex, low physical function, low mid-arm muscle area, low forced expiratory volume in 1 s and anemia was associated with mortality for people 65+. The substitution of anemia with anemia + high level of C-reactive protein (hCRP) and the addition of high brain natriuretic peptide (hBNP) levels improved the classification of older persons at risk for mortality. The combination of low physical function, low mid-arm muscle area, low forced expiratory volume in 1 s, anemia with hCRP levels and hBNP identified older persons at a higher risk for mortality. These predictors may be used for the development of a prediction model to detect older people who are at risk for adverse health outcomes in northwest Russia.

  10. Five decades on: Use of historical weaning size data reveals that a decrease in maternal foraging success underpins the long-term decline in population of southern elephant seals (Mirounga leonina.

    Directory of Open Access Journals (Sweden)

    Ella Clausius

    Full Text Available The population of Southern elephant seals (Mirounga leonina at Macquarie Island has declined since the 1960s, and is thought to be due to changing oceanic conditions leading to reductions in the foraging success of Macquarie Island breeding females. To test this hypothesis, we used a 55-year-old data set on weaning size of southern elephant seals to quantify a decrease in weaning size from a period of population stability in 1950s to its present state of on-going decline. Being capital breeders, the size of elephant seal pups at weaning is a direct consequence of maternal foraging success in the preceding year. During the 1940-1950s, the mean of female pups at weaning was similar between the Heard and Macquarie Island populations, while the snout-tail-length length of male weaners from Heard Island were longer than their conspecifics at Macquarie Island. Additionally, the snout-tail-length of pups at weaning decreased by 3cm between the 1950s and 1990s in the Macquarie Island population, concurrent with the observed population decline. Given the importance of weaning size in determining first-year survival and recruitment rates, the decline in the size at weaning suggests that the decline in the Macquarie Island population has, to some extent, been driven by reduced maternal foraging success, consequent declines in the size of pups at weaning, leading to reduced first-year survival rates and recruitment of breeding females into the population 3 to 4 years later.

  11. Los hacendados y rancheros mayas de Yucatán en el siglo XIX Maya hacendados and rancheros from Yucatán in the 19th Century

    Directory of Open Access Journals (Sweden)

    Laura Machuca Gallegos

    2010-01-01

    Full Text Available No sólo los grupos "blancos" y pudientes de la sociedad tuvieron haciendas, sino también los mayas. Al ser la hacienda una de las pocas actividades económicas productivas que se podían llevar a cabo en la península, algunos mayas (si bien son minoría se volvieron propietarios, incluso tuvieron trabajadores adeudados; por tanto, no permanecieron al margen del desarrollo económico y participaron activamente de éste. Así, en este trabajo nos ocupamos de los amos mayas, seguimos algunas de sus estrategias y reconstruimos sus lazos y sus relaciones. La principal fuente utilizada han sido documentos de carácter notarial, en particular los testamentos, de los cuales se han estudiado algunas variables como la de cónyuge, albacea testamentario y testigo.Haciendas were not exclusive for "white" powerful groups, since they were available for the Maya. Hacienda was one of the only productive economic activities in the peninsula, so the Maya (in spite of being a minority became the owners. They even had debtor workers. They were not marginalized from economic development but rather participated actively in it. This paper studies Maya masters by following some of their strategies and reconstructing both their binds and relations. Our main source are notarial documents, particularly testaments, where some variables like spouse, testamentary executor and witness are studied.

  12. Evidence disputing deforestation as the cause for the collapse of the ancient Maya polity of Copan, Honduras

    Science.gov (United States)

    McNeil, Cameron L.; Burney, David A.; Burney, Lida Pigott

    2009-01-01

    Archaeologists have proposed diverse hypotheses to explain the collapse of the southern Maya lowland cities between the 8th and 10th centuries A.D. Although it generally is believed that no single factor was responsible, a commonly accepted cause is environmental degradation as a product of large-scale deforestation. To date, the most compelling scientific evidence used to support this hypothesis comes from the archaeological site of Copan, Honduras, where the analysis of a sediment core suggested a dramatic increase in forest clearance in the Late Classic period (A.D. 600–900). By contrast, in the work presented here, the authors’ analysis of a longer sediment core demonstrates that forest cover increased from A.D. 400 to A.D. 900, with arboreal pollen accounting for 59.8–71.0% of the pollen assemblage by approximately A.D. 780–980. The highest levels of deforestation are found about 900 B.C. when, at its peak, herb pollen made up 89.8% of the assemblage. A second, although less pronounced, period of elevated deforestation peaked at approximately A.D. 400 when herb pollen reached 65.3% of the assemblage. The first deforestation event likely coincided with the widespread adoption of agriculture, a pattern found elsewhere in Mesoamerica. The second period of forest clearance probably was associated with the incursion of Maya speakers into the Copan Valley and their subsequent construction of the earliest levels of the Copan Acropolis. These results refute the former hypothesis that the ancient Maya responded to their increasingly large urban population by exhausting, rather than conserving, natural resources. PMID:20018691

  13. Condiciones alimentarias de los mayas macehuales de Quintana Roo

    Directory of Open Access Journals (Sweden)

    Virginia Ivonne Sánchez Vázquez

    2011-07-01

    Full Text Available Las políticas alimentarias ofrecen una visión oficial sobre las condiciones de la alimentación en México, y específicamente en el México rural indígena, pero a partir de un estudio de caso con los grupos mayas macehuales de Quintana Roo, se muestra el contexto de confrontación donde las comunidades despliegan sus pautas de reproducción social, ciertamente en desventaja estructural, pero no de manera pasiva, sino creando y recreando opciones bajo su marco cultural situado.

  14. Mayariggauksen Mekanismit : mihin Maya-rigin perustoiminnot pohjautuvat

    OpenAIRE

    Reimi, Roope

    2015-01-01

    Tämä on tutkielma Mayan yleisimpien riggaustyökalujen ja mekanismien toiminnasta ja yleinen katsaus Mayan pohjarakenteeseen. Maya on Autodeskin yleiskäytännöllinen 3D-ohjelmisto, joka on saanut teollisuuden aloilla maineen luotettavana, mutta haastavana animaatioalustana. Tässä tutkielmassa aion selvittää muutamia konsepteja, jotka saattavat hämmentää Mayassa ja avata sen logiikkaa toimintojensa takana. Aion myös pureutua syvemmin muutamien Mayan perus riggaustyökalujen toimintaan ja millaine...

  15. Impacts of Climate Change on the Collapse of Lowland Maya Civilization

    Science.gov (United States)

    Douglas, Peter M. J.; Demarest, Arthur A.; Brenner, Mark; Canuto, Marcello A.

    2016-06-01

    Paleoclimatologists have discovered abundant evidence that droughts coincided with collapse of the Lowland Classic Maya civilization, and some argue that climate change contributed to societal disintegration. Many archaeologists, however, maintain that drought cannot explain the timing or complex nature of societal changes at the end of the Classic Period, between the eighth and eleventh centuries ce. This review presents a compilation of climate proxy data indicating that droughts in the ninth to eleventh century were the most severe and frequent in Maya prehistory. Comparison with recent archaeological evidence, however, indicates an earlier beginning for complex economic and political processes that led to the disintegration of states in the southern region of the Maya lowlands that precedes major droughts. Nonetheless, drought clearly contributed to the unusual severity of the Classic Maya collapse, and helped to inhibit the type of recovery seen in earlier periods of Maya prehistory. In the drier northern Maya Lowlands, a later political collapse at ca. 1000 ce appears to be related to ongoing extreme drought. Future interdisciplinary research should use more refined climatological and archaeological data to examine the relationship between climate and social processes throughout the entirety of Maya prehistory.

  16. Holocene vegetation change in the northern Peten and its implications for Maya prehistory

    Science.gov (United States)

    Wahl, David; Byrne, Roger; Schreiner, Thomas; Hansen, Richard

    2006-05-01

    An ˜8400 cal yr record of vegetation change from the northern Peten, Guatemala, provides new insights into the environmental history of the archaeological area known as the Mirador Basin. Pollen, loss on ignition, and magnetic susceptibility analyses indicate warm and humid conditions in the early to mid-Holocene. Evidence for a decrease in forest cover around 4600 cal yr B.P. coincides with the first appearance of Zea mays pollen, suggesting that human activity was responsible. The period between 3450 cal yr B.P. and 1000 cal yr B.P. is characterized by a further decline in forest pollen types, includes an abrupt increase in weedy taxa, and exhibits the highest magnetic susceptibility values since the early Holocene, all of which suggest further agricultural disturbance in the watershed. A brief drop in disturbance indicators around 1800 cal yr B.P. may represent the Preclassic abandonment of the area. Changing pollen frequencies around 1000 cal yr B.P. indicate a cessation of human disturbance, which represents the Late Classic collapse of the southern Maya lowlands.

  17. The use of blunted Maya crude as alternating fuel to fuel oil; Uso de crudo Maya despuntado como combustiononble alterno al combustoleo

    Energy Technology Data Exchange (ETDEWEB)

    Salinas Bravo, Victor M.; Diego Marin, Antonio; Porcayo C; Jesus [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2001-07-01

    The Mexican fuel oil is characterized by its high viscosity and elevated contents of sulfur and vanadium. This particularity determines a problematic characteristic in the steam generators that use this fuel. Our country produces three types of crude petroleum: Olmeca, Istmo and Maya. The difference between these crudes remains in its density and the sulfur content. The Olmeca crude and the Istmo are classified as super-light and light, respectively; whereas the Maya crude is classified as a heavy crude, with a density of 1.0 to 0.92 g/cm and a minimum sulfur content of 3.3 %. For this reason the processing of the Maya crude is seen as an alternative. A table with the physicochemical analysis and properties of a fuel oil and the blunted Maya crude is given, and another one with the quantitative chemical analysis of some metals in fuel oil and in the blunted Maya crude. The stability tests of the fuel are studied giving a comparison of the effect of the aging time on the viscosity of a fuel oil and of the blunted Maya crude at 60 Celsius degrees. As well as a graph of thermograms obtained of a blunted Maya crude sample and of a typical fuel oil. Finally the corrosion tests are described that allow to know in real time the degradation process by corrosion of the materials. [Spanish] El combustoleo mexicano se caracteriza por su alta viscosidad y elevados contenidos de azufre y vanadio. Esta particularidad determina una problematica caracteristica en los generadores de vapor que utilizan este combustible. Nuestro pais produce tres tipos de petroleo crudo: Olmeca, Istmo y Maya. La diferencia entre estos crudos estriba en su densidad y el contenido de azufre. El crudo Olmeca y el Istmo estan clasificados como superligero y ligero, respectivamente; mientras que el crudo Maya esta clasificado como un crudo pesado, con una densidad de 1.0 a 0.92 g/cm y un contenido minimo de azufre de 3.3 %.Con el proposito se busca la alternativa de procesar el crudo Maya. Se da una tabla

  18. Stylistic Analysis of Maya Angelou’s Equality

    Directory of Open Access Journals (Sweden)

    arina isti'anah

    2017-11-01

    Full Text Available This research presented the stylistic analysis of a poem by Maya Angelou, Equality. The poem was chosen as it became Angelou’s one of well-known poems. The Stylistic analysis aimed at comprehending the meanings of either literary or non-literary text by means of observing the language device used in the texts. In this article, the stylistic analysis was conducted to analyze Maya Angelou’s Equality. To achieve the goal of stylistic analysis, there were some language levels to observe; they were phonological, graphological, grammatical, and semantic levels. In the phonological level, the repetition of rhyme in some stanzas, assonance, consonance, and alliteration were used to voice Angelou’s dream about freedom for black people. In the graphological level, the use of prominent punctuation in stanzas 3, 6, and 9 stressed equality as the requirement for the freedom she expected. In the grammatical level, Angelou used pronoun I and you as the dominant words in the poem, revealed different class the poet experienced in the country. The use of metaphors in the poem brought the same meaning as freedom, voice, effort, and racism that black people experienced in America. This research concludes that stylistics applies to analyze literary work so that thorough appreciation to it can be achieved.

  19. Increasing temperature exacerbated Classic Maya conflict over the long term

    Science.gov (United States)

    Carleton, W. Christopher; Campbell, David; Collard, Mark

    2017-05-01

    The impact of climate change on conflict is an important but controversial topic. One issue that needs to be resolved is whether or not climate change exacerbates conflict over the long term. With this in mind, we investigated the relationship between climate change and conflict among Classic Maya polities over a period of several hundred years (363-888 CE). We compiled a list of conflicts recorded on dated monuments, and then located published temperature and rainfall records for the region. Subsequently, we used a recently developed time-series method to investigate the impact of the climatic variables on the frequency of conflict while controlling for trends in monument number. We found that there was a substantial increase in conflict in the approximately 500 years covered by the dataset. This increase could not be explained by change in the amount of rainfall. In contrast, the increase was strongly associated with an increase in summer temperature. These finding have implications not only for Classic Maya history but also for the debate about the likely effects of contemporary climate change.

  20. Classic Maya civilization collapse related to modest reduction in precipitation

    Science.gov (United States)

    Medina-Elizalde, M.; Rohling, E. J.

    2013-05-01

    The disintegration of the Classic Maya civilization during the Terminal Classic Period (TCP) in the Yucatán Peninsula (YP) and Central America was a complex process that occurred over a ~200-year interval and involved a catastrophic depopulation of the region. While it is well established that the civilization collapse coincided with widespread episodes of drought, their nature and severity remain enigmatic. We present a quantitative analysis that offers a coherent interpretation for four of the most detailed paleoclimate records of the event. The underlying processes driving the patterns and amplitudes of these environmental records during the TCP are evaluated with an isotope mass balance model set up for Lake Chichancanab, located in the YP. We use our hydrological-isotope model (i) to test whether the TCP droughts reflect a persistent summer season southern shift of the intertropical convergence zone and its associated belt of convective activity, away from the YP, and (2) to simulate the development of Lake Chichancanab as a function of weaker perturbations to summer precipitation as reflected by a stalagmite d18O-derived rainfall record from the YP. We conclude that the droughts occurring during the disintegration of the Maya civilization represented up to 40% reduction in annual precipitation, likely due to a reduction in summer season tropical cyclone frequency/intensity. Archaeological and Paleoclimatic records from the Yucatan Peninsula

  1. Finish your film! tips and tricks for making an animated short in Maya

    CERN Document Server

    Roy, Kenny

    2014-01-01

    Finish Your Film! Tips and Tricks for Making an Animated Short in Maya is a first-of-its-kind book that walks the reader step-by-step through the actual production processes of creating a 3D Short film with Maya. Other books focus solely on the creative decisions of 3D Animation and broadly cover the multiple phases of animation production with no real applicable methods for readers to employ. This book shows you how to successfully manage the entire Maya animation pipeline. This book blends together valuable technical tips on film production and real-world shortcuts in a step-by-step approach

  2. Los tablados: Arquitectura vernácula efímera de los pueblos mayas

    OpenAIRE

    Aurelio Sánchez Suárez

    2015-01-01

    La arquitectura vernácula de los mayas de la península de Yucatán, en su representación de la casa maya, es reconocida no solo por el impacto que la cultura maya ha tenido últimamente, sino también por su historia que deviene desde el periodo mesoamericano, durante el cual esta construcción, que continúa vigente como vivienda en la actualidad, fue reproducida en la ornamentación y bóvedas de la arquitectura monumental. Los saberes constructivos, conservados por siglos en la construcción de la...

  3. Una historia de la religión de los antiguos mayas

    OpenAIRE

    Baudez, Claude-François

    2013-01-01

    Estudio cuyo objetivo es abordar la religión de los antiguos mayas desde una perspectiva histórica en su proceso evolutivo, el cual abarca los periodos clásico y posclásico y abordar hasta qué punto la religión maya se vio simultáneamente afectada por el declive de la civilización clásica y por la infiltración de rasgos culturales del Altiplano mexicano. Los análisis tradicionales de la religión de los antiguos mayas permanecen exclusivamente al acecho de las continuidades; luego, concluye...

  4. Deep data science to prevent and treat growth faltering in Maya children.

    Science.gov (United States)

    Varela-Silva, M I; Bogin, B; Sobral, J A G; Dickinson, F; Monserrat-Revillo, S

    2016-06-01

    The Maya people are descended from the indigenous inhabitants of southern Mexico, Guatemala and adjacent regions of Central America. In Guatemala, 50% of infants and children are stunted (very low height-for-age), and some rural Maya regions have >70% children stunted. A large, longitudinal, intergenerational database was created to (1) provide deep data to prevent and treat somatic growth faltering and impaired neurocognitive development, (2) detect key dependencies and predictive relations between highly complex, time-varying, and interacting biological and cultural variables and (3) identify targeted multifactorial intervention strategies for field testing and validation. Contributions to this database included data from the Universidad del Valle de Guatemala Longitudinal Study of Child and Adolescent Development, child growth and intergenerational studies among the Maya in Mexico and studies about Maya migrants in the United States.

  5. Ancient Maya impacts on the Earth's surface: An Early Anthropocene analog?

    Science.gov (United States)

    Beach, Tim; Luzzadder-Beach, Sheryl; Cook, Duncan; Dunning, Nicholas; Kennett, Douglas J.; Krause, Samantha; Terry, Richard; Trein, Debora; Valdez, Fred

    2015-09-01

    The measure of the "Mayacene," a microcosm of the Early Anthropocene that occurred from c. 3000 to 1000 BP, comes from multiple Late Quaternary paleoenvironmental records. We synthesized the evidence for Maya impacts on climate, vegetation, hydrology and the lithosphere, from studies of soils, lakes, floodplains, wetlands and other ecosystems. Maya civilization had likely altered local to regional ecosystems and hydrology by the Preclassic Period (3000-1700 BP), but these impacts waned by 1000 BP. They altered ecosystems with vast urban and rural infrastructure that included thousands of reservoirs, wetland fields and canals, terraces, field ridges, and temples. Although there is abundant evidence that indicates the Maya altered their forests, even at the large urban complex of Tikal as much as 40% of the forest remained intact through the Classic period. Existing forests are still influenced by ancient Maya forest gardening, particularly by the large expanses of ancient stone structures, terraces, and wetland fields that form their substrates. A few studies suggest deforestation and other land uses probably also warmed and dried regional climate by the Classic Period (1700-1100 BP). A much larger body of research documents the Maya impacts on hydrology, in the form of dams, reservoirs, canals, eroded soils and urban design for runoff. Another metric of the "Mayacene" are paleosols, which contain chemical evidence for human occupation, revealed by high phosphorus concentrations and carbon isotope ratios of C4 species like maize in the C3-dominated tropical forest ecosystem. Paleosol sequences exhibit "Maya Clays," a facies that reflects a glut of rapidly eroded sediments that overlie pre-Maya paleosols. This stratigraphy is conspicuous in many dated soil profiles and marks the large-scale Maya transformation of the landscape in the Preclassic and Classic periods. Some of these also have increased phosphorous and carbon isotope evidence of C4 species. We synthesize

  6. Construction of an Yucatec Maya soil classification and comparison with the WRB framework

    OpenAIRE

    Zinck J Alfred; Bautista Francisco

    2010-01-01

    Abstract Background Mayas living in southeast Mexico have used soils for millennia and provide thus a good example for understanding soil-culture relationships and for exploring the ways indigenous people name and classify the soils of their territory. This paper shows an attempt to organize the Maya soil knowledge into a soil classification scheme and compares the latter with the World Reference Base for Soil Resources (WRB). Methods Several participative soil surveys were carried out in the...

  7. Effect of type of binder on growth, digestibility, and energetic balance of Octopus maya

    OpenAIRE

    Rosas, C; Tut, J; Baeza, J; Sanchez, A; Sosa, V; Pascual, C; Arena, L; Domingues, P; Cuzon, Gerard

    2008-01-01

    The present study was designed to test the effects of type of binder on growth, nutritional physiology, total apparent digestibility, and some elements of the energetic balance of early O. maya juveniles. Two experiments were performed. One was aimed at evaluating the effect of type of binder on growth, nutritional physiology, and energetic balance and the other at knowing the effect of the binder on total apparent digestibility of O. maya. Binder type affected growth and survival of early O....

  8. Deep data science to prevent and treat growth faltering in Maya children

    OpenAIRE

    Varela-Silva, M I; Bogin, B; Sobral, J A G; Dickinson, F; Monserrat-Revillo, S

    2016-01-01

    The Maya people are descended from the indigenous inhabitants of southern Mexico, Guatemala and adjacent regions of Central America. In Guatemala, 50% of infants and children are stunted (very low height-for-age), and some rural Maya regions have >70% children stunted. A large, longitudinal, intergenerational database was created to (1) provide deep data to prevent and treat somatic growth faltering and impaired neurocognitive development, (2) detect key dependencies and predictive relations ...

  9. Construction of an Yucatec Maya soil classification and comparison with the WRB framework

    Directory of Open Access Journals (Sweden)

    Zinck J Alfred

    2010-02-01

    Full Text Available Abstract Background Mayas living in southeast Mexico have used soils for millennia and provide thus a good example for understanding soil-culture relationships and for exploring the ways indigenous people name and classify the soils of their territory. This paper shows an attempt to organize the Maya soil knowledge into a soil classification scheme and compares the latter with the World Reference Base for Soil Resources (WRB. Methods Several participative soil surveys were carried out in the period 2000-2009 with the help of bilingual Maya-Spanish-speaking farmers. A multilingual soil database was built with 315 soil profile descriptions. Results On the basis of the diagnostic soil properties and the soil nomenclature used by Maya farmers, a soil classification scheme with a hierarchic, dichotomous and open structure was constructed, organized in groups and qualifiers in a fashion similar to that of the WRB system. Maya soil properties were used at the same categorical levels as similar diagnostic properties are used in the WRB system. Conclusions The Maya soil classification (MSC is a natural system based on key properties, such as relief position, rock types, size and quantity of stones, color of topsoil and subsoil, depth, water dynamics, and plant-supporting processes. The MSC addresses the soil properties of surficial and subsurficial horizons, and uses plant communities as qualifier in some cases. The MSC is more accurate than the WRB for classifying Leptosols.

  10. Construction of an Yucatec Maya soil classification and comparison with the WRB framework.

    Science.gov (United States)

    Bautista, Francisco; Zinck, J Alfred

    2010-02-13

    Mayas living in southeast Mexico have used soils for millennia and provide thus a good example for understanding soil-culture relationships and for exploring the ways indigenous people name and classify the soils of their territory. This paper shows an attempt to organize the Maya soil knowledge into a soil classification scheme and compares the latter with the World Reference Base for Soil Resources (WRB). Several participative soil surveys were carried out in the period 2000-2009 with the help of bilingual Maya-Spanish-speaking farmers. A multilingual soil database was built with 315 soil profile descriptions. On the basis of the diagnostic soil properties and the soil nomenclature used by Maya farmers, a soil classification scheme with a hierarchic, dichotomous and open structure was constructed, organized in groups and qualifiers in a fashion similar to that of the WRB system. Maya soil properties were used at the same categorical levels as similar diagnostic properties are used in the WRB system. The Maya soil classification (MSC) is a natural system based on key properties, such as relief position, rock types, size and quantity of stones, color of topsoil and subsoil, depth, water dynamics, and plant-supporting processes. The MSC addresses the soil properties of surficial and subsurficial horizons, and uses plant communities as qualifier in some cases. The MSC is more accurate than the WRB for classifying Leptosols.

  11. Bioarchaeological investigation of ancient Maya violence and warfare in inland Northwest Yucatan, Mexico.

    Science.gov (United States)

    Serafin, Stanley; Lope, Carlos Peraza; Uc González, Eunice

    2014-05-01

    This study investigates evidence of changes and continuities in ancient Maya violence and warfare in inland northwest Yucatan, Mexico from the Middle Preclassic (600-300 BC) to the Postclassic (AD 1050-1542) through bioarchaeological analysis of cranial and projectile trauma. It is hypothesized that the frequency of violence increases before the Classic Maya collapse and remains high during the Postclassic period. It is also hypothesized that the flat, open terrain was conducive to warfare and resulted in higher trauma frequencies than in other parts of the Maya area. Results show that the frequency of cranial trauma decreases before the Classic collapse and increases in the Postclassic, partially matching the expected chronological trends. The frequency of cranial trauma does not differ significantly from other Maya regions but the pattern does: for all periods, males have more healed injuries than females and they are concentrated on the left side of the anterior of the skull. Some injuries appear to be from small points hafted in wooden clubs. In addition, projectile trauma is evident in a scapula with an embedded arrowhead tip, the first such case reported in a Maya skeleton. Overall, these results suggest greater reliance on open combat and less on raids in this region compared with other parts of the Maya area, possibly due to the flat, open terrain, though the identification of perimortem trauma in both women and men indicates surprise raids on settlements were also practiced. Copyright © 2014 Wiley Periodicals, Inc.

  12. Classic Maya civilization collapse associated with reduction in tropical cyclone activity

    Science.gov (United States)

    Medina, M. A.; Polanco-Martinez, J. M.; Lases-Hernández, F.; Bradley, R. S.; Burns, S. J.

    2013-12-01

    In light of the increased destructiveness of tropical cyclones observed over recent decades one might assume that an increase and not a decrease in tropical cyclone activity would lead to societal stress and perhaps collapse of ancient cultures. In this study we present evidence that a reduction in the frequency and intensity of tropical Atlantic cyclones could have contributed to the collapse of the Maya civilization during the Terminal Classic Period (TCP, AD. 800-950). Statistical comparisons of a quantitative precipitation record from the Yucatan Peninsula (YP) Maya lowlands, based on the stalagmite known as Chaac (after the Mayan God of rain and agriculture), relative to environmental proxy records of El Niño/Southern Oscillation (ENSO), tropical Atlantic sea surface temperatures (SSTs), and tropical Atlantic cyclone counts, suggest that these records share significant coherent variability during the TCP and that summer rainfall reductions between 30 and 50% in the Maya lowlands occurred in association with decreased Atlantic tropical cyclones. Analysis of modern instrumental hydrological data suggests cyclone rainfall contributions to the YP equivalent to the range of rainfall deficits associated with decreased tropical cyclone activity during the collapse of the Maya civilization. Cyclone driven precipitation variability during the TCP, implies that climate change may have triggered Maya civilization collapse via freshwater scarcity for domestic use without significant detriment to agriculture. Pyramid in Tikal, the most prominent Maya Kingdom that collapsed during the Terminal Classic Period (circa C.E. 800-950) Rainfall feeding stalagmites inside Rio Secreto cave system, Yucatan, Mexico.

  13. Plasticity, political economy, and physical growth status of Guatemala Maya children living in the United States.

    Science.gov (United States)

    Bogin, B; Loucky, J

    1997-01-01

    Migration of Maya refugees to the United States since the late 1970s affords the opportunity to study the consequences of life in a new environment on the growth of Maya children. The children of this study live in Indiantown, Florida, and Los Angeles, California. Maya children between 4 and 14 years old (n = 240) were measured for height, weight, fatness, and muscularity. Overall, compared with reference data for the United States, the Maya children are, on average, healthy and well nourished. They are taller and heavier and carry more fat and muscle mass than Maya children living in a village in Guatemala. However, they are shorter, on average, than children of black, Mexican-American, and white ethnicity living in Indiantown. Children of Maya immigrants born in the United States tend to be taller than immigrant children born in Guatemala or Mexico. Families that invest economic and social resources in their children have taller children. More economic successful families have taller children. Migration theory and political economy theory from the social sciences are combined with plasticity theory and life history theory (parental investment) from biology to interpret these data.

  14. Do cycle disturbances explain the age-related decline of female fertility? Cycle characteristics of women aged over 40 years compared with a reference population of young women.

    NARCIS (Netherlands)

    Zonneveld, P. van; Scheffer, G.J.; Broekmans, F.J.; Blankenstein, M.A.; Jong, F.H. de; Looman, C.W.; Habbema, J.D.F.; Velde, E.R. te

    2003-01-01

    BACKGROUND: The cause of declining fertility with age, in women who still have regular menstrual cycles, is not clear. METHODS: Follicle development, endometrial growth and hormonal patterns were evaluated in cycles of older women (aged 41-46 years; n = 26) who previously were normally fertile, and

  15. Chicle harvesting and extractive reserves in the Maya Biosphere b: Reserve

    Energy Technology Data Exchange (ETDEWEB)

    Dugelby, B.L.

    1995-12-31

    Chicle latex has been extracted from the forests of northern Guatemala for over 100 years and is a key element in the extractive reserve component of the Maya Biosphere Reserve. The carrying capacity of the reserve for chicle extraction can be estimated from a model incorporating ecological data (such as latex yields per tree and population structure of chicle trees, Manilkara zapota, Sapot.) with socio-ecological and political information concerning camp and chicle resource availability, harvester tapping behavior, and historical and present-day institutional organization. I estimate that chicle harvestors currently utilize and area larger than the multiple use zone of the reserve in a unsustainable manner. Simple reduction of harvestors numbers will not ensure sustainability; institutional reforms are also in order. Extractive reserves can play an important role in preserving tropical forests. However, their effectiveness is highly dependent on prevailing ecological, socio-economic, and political conditions. Wise planning and management of extractive reserves demands an understanding of the system`s carrying capacity. In addition, a strong institutional foundation is necessary to assure effective monitoring and enforcement of harvesting regulations.

  16. Effects of late Holocene climate variability and anthropogenic stressors on the vegetation of the Maya highlands

    Science.gov (United States)

    Franco-Gaviria, F.; Correa-Metrio, A.; Cordero-Oviedo, C.; López-Pérez, M.; Cárdenes-Sandí, G. M.; Romero, F. M.

    2018-06-01

    Climate variability and human activities have shaped the vegetation communities of the Maya region of southern Mexico and Central America on centennial to millennial timescales. Most research efforts in the region have focused on the lowlands, with relatively little known about the environmental history of the regional highlands. Here we present data from two sediment sequences collected from lakes in the highlands of Chiapas, Mexico. Our aim was to disentangle the relative contributions of climate and human activities in the development of regional vegetation during the late Holocene. The records reveal a long-term trend towards drier conditions with superimposed centennial-scale droughts. A declining moisture trend from 3400 to 1500 cal yr BP is consistent with previously reported southward displacement of the Intertropical Convergence Zone, whereas periodic droughts were probably a consequence of drivers such as El Niño. These conditions, together with dense human occupation, converted the vegetation from forest to more open systems. According to the paleoecological records, cultural abandonment of the area occurred ca. 1500 cal yr BP, favoring forest recovery that was somewhat limited by low moisture availability. About 600 cal yr BP, wetter conditions promoted the establishment of modern montane cloud forests, which consist of a diverse mixture of temperate and tropical elements. The vegetation types that occupied the study area during the last few millennia have remained within the envelope defined by the modern vegetation mosaic. This finding highlights the importance of microhabitats in the maintenance biodiversity through time, even under scenarios of high climate variability and anthropogenic pressure.

  17. Effects of perceived job insecurity on depression, suicide ideation, and decline in self-rated health in Korea: a population-based panel study.

    Science.gov (United States)

    Kim, Min-Seok; Hong, Yun-Chul; Yook, Ji-Hoo; Kang, Mo-Yeol

    2017-10-01

    To investigate the effects of job security on new development of depressive episode, suicide ideation, and decline in self-rated health. Data from the Korea Welfare Panel Study from 2012 to 2015 were analysed. A total of 2912 waged workers self-assessed their depressive episode, suicide ideation, and health annually by answering the questionnaire. Participants were divided into three groups according to the level of job security: high, intermediate and low. To evaluate the influence of job security, we performed survival analysis after stratification by gender with adjustment for covariates. The result was further stratified by whether the respondent was the head of household. After adjusting for covariates, men in low job security group showed significantly higher hazard ratios (HRs) for depression (HR 1.27, 95% CI 1.01-1.60), suicide ideation (HR 3.25, 95% CI 1.72-6.16), and decline in self-rated health (HR 1.73, 95% CI 1.16-2.59). Women showed significantly higher HR of depression in the intermediate (HR 1.37, 95% CI 1.01-1.87) and low (HR 1.50, 95% CI 1.12-1.99) job security group. Male head of household with low job security showed significantly higher HR of depression, suicide ideation, and decline in self-rated health. Non-head-of-household women with intermediate and low job security showed higher risk of depression than those with high job security. We found that perceived job insecurity is associated with the new development of depressive episode, suicide ideation, and decline in self-rated health.

  18. Defining population structure and genetic signatures of decline in the giant garter snake (Thamnophis gigas): implications for conserving threatened species within highly altered landscapes

    Science.gov (United States)

    Wood, Dustin A.; Halstead, Brian J.; Casazza, Michael L.; Hansen, Eric C.; Wylie, Glenn D.; Vandergast, Amy

    2015-01-01

    Anthropogenic habitat fragmentation can disrupt the ability of species to disperse across landscapes, which can alter the levels and distribution of genetic diversity within populations and negatively impact long-term viability. The giant gartersnake (Thamnophis gigas) is a state and federally threatened species that historically occurred in the wetland habitats of California’s Great Central Valley. Despite the loss of 93 % of historic wetlands throughout the Central Valley, giant gartersnakes continue to persist in relatively small, isolated patches of highly modified agricultural wetlands. Gathering information regarding genetic diversity and effective population size represents an essential component for conservation management programs aimed at this species. Previous mitochondrial sequence studies have revealed historical patterns of differentiation, yet little is known about contemporary population structure and diversity. On the basis of 15 microsatellite loci, we estimate population structure and compare indices of genetic diversity among populations spanning seven drainage basins within the Central Valley. We sought to understand how habitat loss may have affected genetic differentiation, genetic diversity and effective population size, and what these patterns suggest in terms of management and restoration actions. We recovered five genetic clusters that were consistent with regional drainage basins, although three northern basins within the Sacramento Valley formed a single genetic cluster. Our results show that northern drainage basin populations have higher connectivity than among central and southern basins populations, and that greater differentiation exists among the more geographically isolated populations in the central and southern portion of the species’ range. Genetic diversity measures among basins were significantly different, and were generally lower in southern basin populations. Levels of inbreeding and evidence of population

  19. Maya phytomedicine in Guatemala - Can cooperative research change ethnopharmacological paradigms?

    Science.gov (United States)

    Hitziger, Martin; Heinrich, Michael; Edwards, Peter; Pöll, Elfriede; Lopez, Marissa; Krütli, Pius

    2016-06-20

    This paper presents one of the first large-scale collaborative research projects in ethnopharmacology, to bring together indigenous stakeholders and scientists both in project design and execution. This approach has often been recommended but rarely put into practice. The study was carried out in two key indigenous areas of Guatemala, for which very little ethnopharmacological fieldwork has been published. To document and characterize the ethno-pharmacopoeias of the Kaqchikel (highlands) and Q'eqchi' (lowlands) Maya in a transdisciplinary collaboration with the two groups Councils of Elders. The project is embedded in a larger collaboration with five Councils of Elders representing important indigenous groups in Guatemala, two of which participated in this study. These suggested healing experts reputed for their phytotherapeutic knowledge and skills. Ethnobotanical fieldwork was carried out over 20 months, accompanied by a joint steering process and validation workshops. The field data were complemented by literature research and were aggregated using a modified version of the International Classification of Diseases (ICD-10) and Trotter & Logan's consensus index. Similar numbers of species were collected in the two areas, with a combined total of 530 species. This total does not represent all of the species used for medicinal purposes. Remedies for the digestive system, the central nervous system & behavioral syndromes, and general tissue problems & infections were most frequent in both areas. Furthermore, remedies for the blood, immune & endocrine system are frequent in the Kaqchikel area, and remedies for the reproductive system are frequent in the Q'eqchi' area. Consensus factors are however low. The Kaqchikel, in contrast to the Q'eqchi', report more remedies for non-communicable illnesses. They also rely heavily on introduced species. The transdisciplinary research design facilitated scientifically rigorous and societally relevant large-scale fieldwork, which

  20. The combined effect of bottom-up and top-down factors on life history and reproduction of Daphnia in the field: is a strategic dilemma underlying population declines?

    Directory of Open Access Journals (Sweden)

    Stephan HÜLSMANN

    2011-08-01

    Full Text Available In a detailed field study covering three years, population dynamics, life history shifts and reproductive patterns of a population of Daphnia galeata were investigated in relation to food availability and dynamics of young of the year fish, the main vertebrate predators. In all years an increase of Daphnia abundance in spring was associated with declining food conditions (clear water stage. The size at maturity (SAM during this period was high and even increased, brood size declined, while egg volume increased. These patterns may be explained as response to food limitation. A decline of Daphnia abundance in every year was associated with increasing food conditions and the end of the clear water stage. Egg volumes as well as the size of egg-carrying daphnids also decreased, while brood size remained at low values. In two years in which these changes were particularly pronounced, the available fish data suggest that both the biomass (determining predation pressure, as well as the size of the fish (determining size selection are important for the observed dynamics. No decrease of SAM occurred as long as fish were smaller than 25 mm TL, when they are still gape-limited and not able to feed on the largest size-classes of Daphnia. Although fish biomass, which should correspond to kairomone level, would have suggested a reduction of SAM as induced defence, probably the selection of small (egg-carrying daphnids by small fish, besides severe food limitation, prevented this response to become effective. The sudden decline of SAM at the end of the clear water stage may not be explained by gradual phenotypic responses or indirect demographic effects, but must be due to an alternation of generations. SAM may be further reduced by direct and indirect effects of predation, interacting with increasing food levels. The Daphnia population is most vulnerable to predation at the time when the new generation takes over. Consequently, predation impact depends on

  1. Los tablados: Arquitectura vernácula efímera de los pueblos mayas

    Directory of Open Access Journals (Sweden)

    Aurelio Sánchez Suárez

    2015-06-01

    Full Text Available La arquitectura vernácula de los mayas de la península de Yucatán, en su representación de la casa maya, es reconocida no solo por el impacto que la cultura maya ha tenido últimamente, sino también por su historia que deviene desde el periodo mesoamericano, durante el cual esta construcción, que continúa vigente como vivienda en la actualidad, fue reproducida en la ornamentación y bóvedas de la arquitectura monumental. Los saberes constructivos, conservados por siglos en la construcción de la casa maya, fueron también empleados para la creación de una nueva estructura llamada "tablado", la que se generó durante el proceso de apropiación de la tauromaquia por parte de los mayas peninsulares, asignándole significados propios de su cosmovisión. El presente trabajo detalla una parte de los resultados del proyecto de investigación que propone una mirada a esta expresión vernácula en los estados de Campeche y Yucatán, en México.

  2. Los mayas del altiplano: supervivencia indígena en Chiapas y Guatemala

    Directory of Open Access Journals (Sweden)

    Lovell, W. George

    2002-06-01

    Full Text Available En el contexto americano, pocos grupos indígenas han demostrado la capacidad de sobrevivir a lo largo de la historia como los mayas del altiplano. Hoy día en Chiapas existen más de un millón de indígenas mayas, un número que asciende a cinco o seis millones en el caso de Guatemala. Los pueblos mayas han respondido a la invasión y a la dominación para conservar elementos importantes de su cultura. Este artículo discute las formas en que los mayas del altiplano se han adaptado para sobrevivir a casi cinco siglos de conquista, identificando tres fases claves en su trayectoria histórica: (1 la experiencia colonial, que abarca los años entre 1524 y 1821; (2 una época de reforma y revolución, que corre de 1821 a 1954; y (3 un período de marginalización y descuido desde 1954 en adelante. Pese al desfío, los mayas del altiplano están equipados culturalmente para perdurar.

  3. Performance of the 16-Item Informant Questionnaire on Cognitive Decline for the Elderly (IQCODE) in an Arabic-Speaking Older Population

    DEFF Research Database (Denmark)

    Phung, Thien Kieu Thi; Chaaya, Monique; Asmar, Khalil

    2015-01-01

    BACKGROUND/AIM: The North African and Middle Eastern region has high illiteracy rates among older people, making direct cognitive testing challenging. Validated screening instruments for dementia in Arabic are lacking. We aimed to validate the Arabic version of the 16-item Informant Questionnaire...... on Cognitive Decline for the Elderly (A-IQCODE 16) for screening for dementia through an informant. METHODS: 236 Lebanese participants older than 65 years, 143 with normal cognition and 93 with mild-to-moderate dementia according to the DSM-IV criteria, and their informants were recruited. Half...

  4. An 8700 year paleoclimate reconstruction from the southern Maya lowlands

    Science.gov (United States)

    Wahl, David B.; Byrne, Roger; Anderson, Lysanna

    2014-01-01

    Analysis of a sediment core from Lago Puerto Arturo, a closed basin lake in northern Peten, Guatemala, has provided an ∼8700 cal year record of climate change and human activity in the southern Maya lowlands. Stable isotope, magnetic susceptibility, and pollen analyses were used to reconstruct environmental change in the region. Results indicate a relatively wet early to middle Holocene followed by a drier late Holocene, which we interpret as reflecting long-term changes in insolation (precession). Higher frequency variability is more likely attributable to changes in ocean/atmosphere circulation in both the North Atlantic and the Pacific Oceans. Pollen and isotope data show that most of the period of prehispanic agricultural settlement, i.e. ∼5000–1000 cal yr BP, was characterized by drier conditions than previous or subsequent periods. The presence ofZea (corn) pollen through peak aridity during the Terminal Classic period (∼1250–1130 cal yr BP) suggests that drought may not have had as negative an impact as previously proposed. A dramatic negative shift in isotope values indicates an increase in precipitation after ∼950 cal yr BP (hereafter BP).

  5. TEATRO MAYA: RABINAL ACHÍ O DANZA DEL TUN

    Directory of Open Access Journals (Sweden)

    Patricia Henríquez Puentes

    2007-04-01

    Full Text Available El Rabinal Achí o Danza del Tun es teatro de origen maya puesto en escena desde el siglo XIII hasta nuestros días en la actual Guatemala. Es una composición inserta en el esquema religioso de las culturas mesoamericanas que, conservada a través de tradición oral hasta el siglo XIX, ha sido reescrita en este espacio escénico durante aproximadamente ochocientos años. El Rabinal Achí revela una forma de escribir con el cuerpo que articula danza, música y poesía, y representa ese momento en la historia del teatro en que el arte de la representación y rito compartían la misma escenaThe Rabinal Achí or Dance of the Tun is theatre of Mayan origen. The first performances date from the 13th century and continue into the present day in contemporary Guatemala. It is a composition that forms part of the religious scheme of the Indo-American cultures and, preserved through oral tradition up until the 19th century, has been rewritten in this scenic space for approximately eight hundred years. The Rabinal Achí reveals a way of writing with the body that articulates dance, music and poetry and represents a moment in the history of theatre in which the art of representation and the ritual share the same scene

  6. Maya Children. Helpers at the Farm (Karen L. Kramer

    Directory of Open Access Journals (Sweden)

    Gema Campos Hernando

    2007-01-01

    Full Text Available Los habitantes de Xculoc, una aldea maya en la península de Yucatán, viven de sus cultivos de maíz y mantienen una agricultura de subsistencia sin haber entrado a formar parte del mercado laboral ni de la economía regional. La aldea, en la que viven 316 habitantes distribuidos en 55 casas familiares, está a cinco horas de camino de cualquier vía asfaltada, sin electricidad ni agua corriente. Los habitantes de Xculoc tienen de particular una tasa de natalidad muy alta y una mortalidad infantil muy baja, en parte por la ausencia de aguas contaminadas en los alrededores del poblado, llegando a conformarse el núcleo familiar por la madre, el padre y hasta ocho hijos. Esta estructura familiar no se podría mantener con el exclusivo trabajo de los padres , las necesidades de consumo son cubiertas por todos los miembros de la familia, dependiendo sus aportaciones no sólo del tamaño de la familia sino también de la estructura de la misma según edades.

  7. Paleoenvironmental and Paleoecological Reconstruction of the Ancient Maya Port Site of Vista Alegre, Quintana Roo, Mexico

    Science.gov (United States)

    Rissolo, D.; Jaijel, R.; Glover, J. B.; Goodman, B.; Beddows, P. A.; Carter, A.; Smith, D.

    2013-12-01

    Ancient Maya ports along the largely unstudied northeast coast of the Yucatan Peninsula once supported a network of trade routes linking people, goods, and ideas from across Mesoamerica. The Costa Escondida Project has focused on the interrelationships between the ancient Maya and their dynamic coastal environment along the shores of the Laguna Holbox. Central to our interdisciplinary efforts is a paleoenvironmental and paleoecological reconstruction of the key port of Vista Alegre - a low-lying island surrounded by a complex mosaic of costal ecosystems, sedimentological facies, and hydrological conditions. Geoarchaeological field methods, such as sediment coring, have made possible multiproxy analyses that enable us to better understand sea level fluctuations and the morphology of the shoreline and harboring locations over time, as well as changes in ecosystem biodiversity, which would have presented the maritime Maya with unique challenges and opportunities.

  8. Correlating the Ancient Maya and Modern European Calendars with High-Precision AMS 14C Dating

    Science.gov (United States)

    Kennett, Douglas J.; Hajdas, Irka; Culleton, Brendan J.; Belmecheri, Soumaya; Martin, Simon; Neff, Hector; Awe, Jaime; Graham, Heather V.; Freeman, Katherine H.; Newsom, Lee; Lentz, David L.; Anselmetti, Flavio S.; Robinson, Mark; Marwan, Norbert; Southon, John; Hodell, David A.; Haug, Gerald H.

    2013-04-01

    The reasons for the development and collapse of Maya civilization remain controversial and historical events carved on stone monuments throughout this region provide a remarkable source of data about the rise and fall of these complex polities. Use of these records depends on correlating the Maya and European calendars so that they can be compared with climate and environmental datasets. Correlation constants can vary up to 1000 years and remain controversial. We report a series of high-resolution AMS 14C dates on a wooden lintel collected from the Classic Period city of Tikal bearing Maya calendar dates. The radiocarbon dates were calibrated using a Bayesian statistical model and indicate that the dates were carved on the lintel between AD 658-696. This strongly supports the Goodman-Martínez-Thompson (GMT) correlation and the hypothesis that climate change played an important role in the development and demise of this complex civilization.

  9. Raman spectroscopic analysis of the Maya wall paintings in Ek'Balam, Mexico

    Science.gov (United States)

    Vandenabeele, P.; Bodé, S.; Alonso, A.; Moens, L.

    2005-08-01

    Raman spectroscopy has been applied to the examination of wall painting fragments from the archaeological site of Ek'Balam (Yucatán, Mexico). Thirty-three samples have been studied, all originating from room 23 of the Acropolis, and being representative of the painting technique at Ek'Balam during the late Classic Maya period. Several pigments such as haematite, calcite, carbon, cinnabar and indigo were identified in these samples. The latter pigment was presumed to be present as 'Maya blue', which is an intercalation product of indigo and palygorskite clay. The observed Raman spectra are reported and some band assignments have been made. This survey is the first Raman spectroscopic examination of a whole set of pigments in archaeological Maya wall painting fragments.

  10. Lead (Pb) Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region

    Science.gov (United States)

    Kamenov, George D.; Gilli, Adrian; Hodell, David A.; Emery, Kitty F.; Brenner, Mark; Krigbaum, John

    2016-01-01

    We examined the potential use of lead (Pb) isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1) geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb), and 2) a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr) and oxygen (δ18O), a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region. PMID:27806065

  11. Lead (Pb) Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region.

    Science.gov (United States)

    Sharpe, Ashley E; Kamenov, George D; Gilli, Adrian; Hodell, David A; Emery, Kitty F; Brenner, Mark; Krigbaum, John

    2016-01-01

    We examined the potential use of lead (Pb) isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1) geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb), and 2) a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr) and oxygen (δ18O), a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region.

  12. The nine lives of a threatened felid in a human-dominated landscape: assessing population decline drivers of the guiña (Leopardus guigna)

    OpenAIRE

    Gálvez, Nicolás

    2015-01-01

    The world's human population and an expanding agricultural frontier are exerting increasing pressure on the Earth's systems that sustain life resulting in unprecedented levels of biodiversity loss. Carnivores, which play a key role in ecosystem function and integrity, are also particularly threatened by habitat loss and killing by humans in response to livestock predation. At the same time carnivores, particularly felids show a paucity of studies that suggests population assessments and long-...

  13. Bigger Is Fitter? Quantitative Genetic Decomposition of Selection Reveals an Adaptive Evolutionary Decline of Body Mass in a Wild Rodent Population.

    OpenAIRE

    Timothée Bonnet; Peter Wandeler; Glauco Camenisch; Erik Postma

    2017-01-01

    In natural populations, quantitative trait dynamics often do not appear to follow evolutionary predictions: Despite abundant examples of natural selection acting on heritable traits, conclusive evidence for contemporary adaptive evolution remains rare for wild vertebrate populations, and phenotypic stasis seems to be the norm. This so-called ‘stasis paradox’ highlights our inability to predict evolutionary change, which is especially concerning within the context of rapid anthropogenic enviro...

  14. Chinese culture and fertility decline.

    Science.gov (United States)

    Wu, C; Jia, S

    1992-01-01

    Coale has suggested that cultural factors exert a significant influence on fertility reduction; countries in the "Chinese cultural circle" would be the first to show fertility decline. In China, the view was that traditional Chinese culture contributed to increased population. This paper examines the nature of the relationship between Chinese culture and fertility. Attention was directed to a comparison of fertility rates of developing countries with strong Chinese cultural influence and of fertility within different regions of China. Discussion was followed by an explanation of the theoretical impact of Chinese culture on fertility and direct and indirect beliefs and practices that might either enhance or hinder fertility decline. Emigration to neighboring countries occurred after the Qing dynasty. Fertility after the 1950s declined markedly in Japan, Singapore, Hong Kong, South Korea, Taiwan, and mainland China: all countries within the Chinese cultural circle. Other countries within the Chinese circle which have higher fertility, yet lower fertility than other non-Chinese cultural countries, are Malaysia, Thailand, and Indonesia. Within China, regions with similar fertility patterns are identified as coastal regions, central plains, and mountainous and plateau regions. The Han ethnic group has lower fertility than that of ethnic minorities; regions with large Han populations have lower fertility. Overseas Chinese in East Asian countries also tend to have lower fertility than their host populations. Chinese culture consisted of the assimilation of other cultures over 5000 years. Fertility decline was dependent on the population's desire to limit reproduction, favorable social mechanisms, and availability of contraception: all factors related to economic development. Chinese culture affects fertility reduction by affecting reproductive views and social mechanisms directly, and indirectly through economics. Confucianism emphasizes collectivism, self

  15. The Costa Maya:  Evolution of a Touristic Landscape La Costa Maya : évolution d'un paysage touristique La Costa Maya : evolución de un paisaje turístico

    Directory of Open Access Journals (Sweden)

    Klaus J. Meyer-Arendt

    2010-06-01

    Full Text Available La Costa Maya est une région côtière du sud du Quintana Roo (Mexique, proche de l'îlet Ambergris au Bélize. Contrairement à la côte caribéenne du Mexique qui a souffert du développement du tourisme de masse à Cancun et le long de la Riviera Maya, la Costa Maya s'est orientée vers un développement durable avec notamment une faible densité de construction et le développement de l'écotourisme.Le développement s'est concentré autour de Puerto Costa Maya où un terminal de croisière a été construit en 2001. La station balnéaire (balneario de Majahual est devenue dépendante des 10-12 bateaux de touristes qui débarquaient chaque semaine. En dépit d'importants plans de développement, les plages reculées de la Costa Maya accueillaient tout au plus des écotouristes aisés et du tourisme lié à la plongée sous-marine.Le cyclone Dean, de catégorie 5, a dévasté le paysage en août 2007 et le rétablissement économique n'a pu être entamé que fin 2008, après la réouverture du terminal de croisière et la reconstruction de Majahual. Fin 2009, le trafic de croisière n'a pas retrouvé son niveau d'avant Dean et la récession mondiale couplée avec la grippe porcine et les violences liées à la drogue ont fait diminuer le tourisme en provenance des Etats-Unis. On ignore à quel niveau les nouvelles infrastructures tels l'aéroport international de Tulum qui propose un itinéraire de Chetumal à la plage et le nouveau complexe hôtelier à Xahuayxel, stimuleront la Costa Maya mexicaine créant peut-être une autoroute côtière reliée à San Pedro au Bélize.The Costa Maya is a vernacular coastal region of southeastern Quintana Roo (Mexico and adjacent Ambergris Cay, Belize.  As Mexico’s Caribbean coast suffered many growth pains associated with mass tourism development in Cancun and along the Riviera Maya, the Costa Maya by contrast was projected for more sustainable development including low-density housing and

  16. El Teatro Maya como travestismo cultural. Una lectura performativa y descolonizadora de su arquitectura

    OpenAIRE

    Hoechtl, Nina

    2015-01-01

    Este texto emula la forma y estructura de un guion dramático. En él se desarrolla una visita guiada al Teatro Maya, a través de la cual se pretende mostrar las maneras en que lo cultural diferente y lo cultural exótico habitan la arquitectura. El texto aborda este análisis desde una perspectiva específica, la del travestismo cultural, poniendo especial atención en el contexto arquitectónico, cultural e histórico particular del Teatro Maya, que se inauguró en 1927 en el Centro de Los Angeles e...

  17. A configuração narrativa em idioma maya q'eqchi de Guatemala

    OpenAIRE

    Bol, Oscar René Saquil

    2006-01-01

    Guatemala é um país que tem um tecido social composto por diferentes culturas (Maya, Xinca, Garifuna y Ladina). Entre elas o Q'eqchi' como idioma e cultura maya, sobre o qual se desenvolve esta investigação, no campo das ciências da linguagem, adotando os aportes da linguística textual. Neste processo participaram mestres (professores) que trabalham em cinco escolas de Xch'ool Ixim, eles recolheram algumas narrações que se utilizam para a trasmissão de determinados ensinamentos e emoções, ...

  18. Transcultural use of narcotic water lilies in ancient Egyptian and Maya drug ritual.

    Science.gov (United States)

    Emboden, W A

    1981-01-01

    Comparisons are made between ancient ritual uses of the flowers of Nymphaea (Nymphaeaceae) in Maya and Egyptian civilizations. Recurrent motifs encountered in the art of both of these ancient civilizations suggests that the role fo the water lily was that of a narcotic (psychodysleptic) used to mediate ecstasis among a priestly caste. Relevant literature is reviewed as are chemical data. Elements in the complex belief systems of these two civilizations need to be reinterpreted in view of the use of two water lilies as ritual narcotics. The species implicated are Nymphaea caerulea Sav., in Egypt, and N. ampla DC., among the Maya.

  19. Radar mapping, archaeology, and ancient land use in the Maya lowlands

    Science.gov (United States)

    Adams, R. E. W.; Brown, W. E., Jr.; Culbert, T. P.

    1981-01-01

    Data from the use of synthetic aperture radar in aerial survey of the southern Maya lowlands suggest the presence of very large areas drained by ancient canals for the purpose of intensive cultivation. Preliminary ground checks in several very limited areas confirm the existence of canals and raised fields. Excavations and ground surveys by several scholars provide valuable comparative information. Taken together, the new data suggest that Late Classic period Maya civilization was firmly grounded in large-scale and intensive cultivation of swampy zones.

  20. Social structural consequences of population growth.

    Science.gov (United States)

    Adams, R E

    1981-01-01

    Estimates from archaeological data of the numbers in the elite classes, nonelite occupational specialists, density of population, city size, and size of political units in the ancient Maya civilization suggest that there was a quantum shift in rate of development in the Early Classic period, associated with intensification of agriculture, and that the social structure approximated to a generalized feudal pattern.

  1. Lung function decline in COPD

    Directory of Open Access Journals (Sweden)

    Tantucci C

    2012-02-01

    Full Text Available Claudio Tantucci, Denise ModinaUnit of Respiratory Medicine, Department of Medical and Surgical Sciences, University of Brescia, Brescia, ItalyAbstract: The landmark study of Fletcher and Peto on the natural history of tobacco smoke-related chronic airflow obstruction suggested that decline in the forced expiratory volume in the first second (FEV1 in chronic obstructive pulmonary disease (COPD is slow at the beginning, becoming faster with more advanced disease. The present authors reviewed spirometric data of COPD patients included in the placebo arms of recent clinical trials to assess the lung function decline of each stage, defined according to the severity of airflow obstruction as proposed by the Global Initiative for Chronic Obstructive Lung Disease (GOLD guidelines. In large COPD populations the mean rate of FEV1 decline in GOLD stages II and III is between 47 and 79 mL/year and 56 and 59 mL/year, respectively, and lower than 35 mL/year in GOLD stage IV. Few data on FEV1 decline are available for GOLD stage I. Hence, the loss of lung function, assessed as expiratory airflow reduction, seems more accelerated and therefore more relevant in the initial phases of COPD. To have an impact on the natural history of COPD, it is logical to look at the effects of treatment in the earlier stages.Keywords: chronic obstructive pulmonary disease, decline, forced expiratory volume in 1 second, FEV1

  2. Bigger Is Fitter? Quantitative Genetic Decomposition of Selection Reveals an Adaptive Evolutionary Decline of Body Mass in a Wild Rodent Population.

    Directory of Open Access Journals (Sweden)

    Timothée Bonnet

    2017-01-01

    Full Text Available In natural populations, quantitative trait dynamics often do not appear to follow evolutionary predictions. Despite abundant examples of natural selection acting on heritable traits, conclusive evidence for contemporary adaptive evolution remains rare for wild vertebrate populations, and phenotypic stasis seems to be the norm. This so-called "stasis paradox" highlights our inability to predict evolutionary change, which is especially concerning within the context of rapid anthropogenic environmental change. While the causes underlying the stasis paradox are hotly debated, comprehensive attempts aiming at a resolution are lacking. Here, we apply a quantitative genetic framework to individual-based long-term data for a wild rodent population and show that despite a positive association between body mass and fitness, there has been a genetic change towards lower body mass. The latter represents an adaptive response to viability selection favouring juveniles growing up to become relatively small adults, i.e., with a low potential adult mass, which presumably complete their development earlier. This selection is particularly strong towards the end of the snow-free season, and it has intensified in recent years, coinciding which a change in snowfall patterns. Importantly, neither the negative evolutionary change, nor the selective pressures that drive it, are apparent on the phenotypic level, where they are masked by phenotypic plasticity and a non causal (i.e., non genetic positive association between body mass and fitness, respectively. Estimating selection at the genetic level enabled us to uncover adaptive evolution in action and to identify the corresponding phenotypic selective pressure. We thereby demonstrate that natural populations can show a rapid and adaptive evolutionary response to a novel selective pressure, and that explicitly (quantitative genetic models are able to provide us with an understanding of the causes and consequences of

  3. Bigger Is Fitter? Quantitative Genetic Decomposition of Selection Reveals an Adaptive Evolutionary Decline of Body Mass in a Wild Rodent Population

    Science.gov (United States)

    Wandeler, Peter; Camenisch, Glauco

    2017-01-01

    In natural populations, quantitative trait dynamics often do not appear to follow evolutionary predictions. Despite abundant examples of natural selection acting on heritable traits, conclusive evidence for contemporary adaptive evolution remains rare for wild vertebrate populations, and phenotypic stasis seems to be the norm. This so-called “stasis paradox” highlights our inability to predict evolutionary change, which is especially concerning within the context of rapid anthropogenic environmental change. While the causes underlying the stasis paradox are hotly debated, comprehensive attempts aiming at a resolution are lacking. Here, we apply a quantitative genetic framework to individual-based long-term data for a wild rodent population and show that despite a positive association between body mass and fitness, there has been a genetic change towards lower body mass. The latter represents an adaptive response to viability selection favouring juveniles growing up to become relatively small adults, i.e., with a low potential adult mass, which presumably complete their development earlier. This selection is particularly strong towards the end of the snow-free season, and it has intensified in recent years, coinciding which a change in snowfall patterns. Importantly, neither the negative evolutionary change, nor the selective pressures that drive it, are apparent on the phenotypic level, where they are masked by phenotypic plasticity and a non causal (i.e., non genetic) positive association between body mass and fitness, respectively. Estimating selection at the genetic level enabled us to uncover adaptive evolution in action and to identify the corresponding phenotypic selective pressure. We thereby demonstrate that natural populations can show a rapid and adaptive evolutionary response to a novel selective pressure, and that explicitly (quantitative) genetic models are able to provide us with an understanding of the causes and consequences of selection that is

  4. Advanced long-term bird banding and climate data mining in spring confirm passerine population declines for the Northeast Chinese-Russian flyway

    Science.gov (United States)

    Jiao, Shengwu; Huettmann, Falk; Guo, Yumin; Li, Xianda; Ouyang, Yanlan

    2016-09-01

    The migration of birds is fascinating for humans but it's also a serious environmental monitoring and management issue on a global level. Bird banding using mistnets has been the method of choice for decades worldwide; linking these data with climate data allows to infer on global warming and outlier events. However, good methods to achieve this effectively in time and space for many species are still missing; data for Asia are specifically sparse and often 'messy'. Here we present a data mining summary information for data from two bird banding stations (Gaofeng and Qingfeng) along the vast Northeast Chinese-Russian flyway. Bird data were collected during spring 2002-2011 with standardized techniques and then linked with related climate data in the banding as well as the wintering sites. This creates a complex data set which is based on a decade and which includes many predictors. This first-time data mining analysis with 'data cloning' and machine learning methods (boosted regression trees) shows how to extract the major signals in this unique dataset from highly correlated and interacting predictors. Our results indicate a large-scale warming trend for the flyway, with a start in 2003, and a freezing rain outlier event in 2008; the last years remained on a rather warm level. All evidence along this vast flyway supports major changes, warming trends, habitat losses and consequently strong passerine declines. Presumably human pressures are a major factor either way and we propose to address these problems immediately for betterment if meaningful conservation targets are to be met.

  5. Emerging factors associated with the decline of a gray fox population and multi-scale land cover associations of mesopredators in the Chicago metropolitan area.

    Energy Technology Data Exchange (ETDEWEB)

    Willingham, Alison N.; /Ohio State U.

    2008-01-01

    Statewide surveys of furbearers in Illinois indicate gray (Urocyon cinereoargenteus) and red (Vulpes vulpes) foxes have experienced substantial declines in relative abundance, whereas other species such as raccoons (Procyon lotor) and coyotes (Canis latrans) have exhibited dramatic increases during the same time period. The cause of the declines of gray and red foxes has not been identified, and the current status of gray foxes remains uncertain. Therefore, I conducted a large-scale predator survey and tracked radiocollared gray foxes from 2004 to 2007 in order to determine the distribution, survival, cause-specific mortality sources and land cover associations of gray foxes in an urbanized region of northeastern Illinois, and examined the relationships between the occurrence of gray fox and the presence other species of mesopredators, specifically coyotes and raccoons. Although generalist mesopredators are common and can reach high densities in many urban areas their urban ecology is poorly understood due to their secretive nature and wariness of humans. Understanding how mesopredators utilize urbanized landscapes can be useful in the management and control of disease outbreaks, mitigation of nuisance wildlife issues, and gaining insight into how mesopredators shape wildlife communities in highly fragmented areas. I examined habitat associations of raccoons, opossums (Didelphis virginiana), domestic cats (Felis catus), coyotes, foxes (gray and red), and striped skunks (Mephitis mephitis) at multiple spatial scales in an urban environment. Gray fox occurrence was rare and widely dispersed, and survival estimates were similar to other studies. Gray fox occurrence was negatively associated with natural and semi-natural land cover types. Fox home range size increased with increasing urban development suggesting that foxes may be negatively influenced by urbanization. Gray fox occurrence was not associated with coyote or raccoon presence. However, spatial avoidance and

  6. Decline traffic information system

    Energy Technology Data Exchange (ETDEWEB)

    Du Plessis, K [Computer Sciences Corporation (CSC), Sydney (Australia)

    2007-09-06

    BHP Billion (BHPB) Cannington has experienced problems in regards to their traffic flow in the decline at the mine. The problems related to reports on near misses of vehicles moving towards each other in the decline. The decline is also to narrow for trucks to pass each other and the operators need to be aware of oncoming traffic in the decline to ensure they could take early evasive steps to ensure the rules of right of way in the decline are adhered to. BHPB Cannington requested CSC to conduct a problem analysis and to provide a solutions proposal to Cannington. The solution was put forward as an augmentation of their current safety procedures used with in the decline. During this phase of the project CSC developed a solutions architecture which involved the use of Active (Radio Frequency Identification) RFID tagging which will enable vehicle movement tracking on a real time basis after which the appropriate traffic movement can be relayed to the operators in the decline. The primary objective of the DTIS is to provide accurate information of traffic movement in the decline and present that information to the operators of the decline IN THE DECLINE upon which they would make their decisions. (orig.)

  7. Story Starters on the Aztecs, Incas, and Mayas. A Creative Writing Program.

    Science.gov (United States)

    Henrich, Steve; Henrich, Jean

    Designed to supplement an established language arts and social studies program, this books deals with the Aztecs, Incas, and Mayas of Latin America. All of the "Story Starter" books are intended to give a variety of vocabulary and story ideas to help with the writing process. Each of the books is divided into four main sections: (1) an…

  8. The importance of considering gestures in the study of current spoken Yucatec Maya.

    Directory of Open Access Journals (Sweden)

    Olivier Le Guen

    2018-02-01

    Full Text Available For centuries, linguistic description has been somehow limited because it was not possible to record audio and video. For this reason, the intrinsic multimodal nature of human language has been left out, putting aside various types of information both prosodic and visual. This work analyzes the ways in which gestures complement speech, taking into account several levels of analysis: pragmatic, semantic and syntactic; but also how some gestures can be considered linguistic signs. In order to exemplify the argumentation, I will consider the Yucatec Maya language using examples of spontaneous productions. Although certain processes presented in this work are specific to Yucatec Maya, most can be found in various languages. This paper first presents a definition of language, speech and gestures, and how one can study the way in which speech and gestures are integrated in a composite utterance. Subsequently, I analyze examples of different types of gestures in various areas of communication in Yucatec Maya, such as deictic gestures, the use of expressive gestures, metaphors and the integration of gestures at the pragmatic level. Finally, I explain how gestures can become linguistic signs in Yucatec Maya.

  9. THE MAYA INDEX ANALYSIS ON DENGUE PATIENT HOUSEHOLD IN BANJAR CITY, 2012

    Directory of Open Access Journals (Sweden)

    Pandji Wibawa Dhewantara

    2015-07-01

    Full Text Available Salah satu faktor risiko kejadian DBD di antaranya adalah ketersediaan kontainer tempat perkembangbiakan vektor. Tahun2012 dilakukan survei observasional analitik dengan pendekatan potong lintang pada 100 rumah penderita DBD di KotaBanjar. Tujuan penelitian untuk mengetahui tingkat risiko penularan DBD melalui pendekatan analisis Maya Index. Datayang dikumpulkan meliputi jenis, jumlah kontainer, dan jumlah kontainer mengandung larva Aedes sp. Kontainer yangditemukan dikategorikan menjadi Controllable Container dan Disposable Container untuk mengetahui Breeding Risk Index(BRI dan Hygene Risk Index (HRI. Analisis deskriptif digunakan untuk mengetahui proporsi jumlah dan jenis kontainer.Maya index diperoleh dari hasil pengkategorian rasio BRI dan HRI. Container Index dan Breteau Index dihitung untukmengetahui kepadatan larva. Hasil pengamatan ditemukan sebanyak 915 kontainer yang terdiri dari jenis controllablecontainers (93% dan disposable containers (7%. Jenis kontainer yang dominan adalah tempayan tanah liat (15,52%, bakair (14,35%, pot bunga (48,47%, dan penampung air pada dispenser (7%. Larva Aedes sp. banyak ditemukan pada bak air(48,57% dan penampung air pada dispenser (22,86%. Sementara, botol bekas (35,3% dan kaleng bekas (26,1%merupakan jenis disposable container yang paling banyak ditemukan. Analisis menunjukkan sebagian besar rumahberkategori BRI tinggi (93% dan HRI rendah (92%. Berdasarkan Maya Index, rumah penderita termasuk dalam kategoririsiko sedang (97% dengan CI dan BI masing-masing sebesar 3,85% dan 35. Studi ini menyimpulkan bahwa sebagian besarrumah penderita masih memiliki potensi penularan infeksi virus Dengue.Kata kunci: DBD, risiko perkembangbiakan larva, kontainer, indeks risiko kebersihan, Maya Index

  10. Incorporation, integration and irrigation at the ancient Maya site of Baking Pot, Belize

    Directory of Open Access Journals (Sweden)

    James M. Conlon

    1995-11-01

    Full Text Available This paper provides an example of the use of corporate group analysis at the major ceremonial centre of Baking Pot, and uses comparative data from the site core of Baking Pot, other major centres in the upper Belize Valley, and various other sources throughout the Maya lowlands.

  11. Bilingual Rapping in Yucatán, Mexico: Strategic Choices for Maya Language Legitimation and Revitalisation

    Science.gov (United States)

    Cru, Josep

    2017-01-01

    This paper explores the sociolinguistic practices of a group of young bilingual rappers in the Yucatán Peninsula of Mexico. Against the background of ongoing language shift to Spanish in the region, the language choices of a group of Maya youths involved in Hip Hop culture and their agency as policy-makers at the grassroots level is analysed.…

  12. Maya Angelou's Children's Books: Inspiration for Turning Poetry into Music

    Science.gov (United States)

    Beegle, Amy C.

    2014-01-01

    This column presents books for children penned by Maya Angelou. These poems and stories, based on her experiences as an African American woman living in the United States, Egypt, Ghana, and South Africa, include extraordinary photography and artwork. Suggestions for inclusion in the general music classroom are provided.

  13. Leveraging Social Networks to Support Reproductive Health and Economic Wellbeing among Guatemalan Maya Women

    Science.gov (United States)

    Prescott, Alexandra S.; Luippold-Roge, Genevieve P.; Gurman, Tilly A.

    2016-01-01

    Objective: Maya women in Guatemala are disproportionately affected by poverty and negative reproductive health outcomes. Although social networks are valued in many Indigenous cultures, few studies have explored whether health education programmes can leverage these networks to improve reproductive health and economic wellbeing. Design: This…

  14. Chemical Tools of Octopus maya during Crab Predation Are Also Active on Conspecifics.

    Science.gov (United States)

    Pech-Puch, Dawrin; Cruz-López, Honorio; Canche-Ek, Cindy; Campos-Espinosa, Gabriela; García, Elpidio; Mascaro, Maite; Rosas, Carlos; Chávez-Velasco, Daniel; Rodríguez-Morales, Sergio

    2016-01-01

    Octopus maya is a major socio-economic resource from the Yucatán Peninsula in Mexico. In this study we report for the first time the chemical composition of the saliva of O. maya and its effect on natural prey, i.e. the blue crab (Callinectes sapidus), the crown conch snail (Melongena corona bispinosa), as well as conspecifics. Salivary posterior glands were collected from octopus caught by local fishers and extracted with water; this extract paralyzed and predigested crabs when it was injected into the third pereiopod. The water extract was fractionated by membrane ultrafiltration with a molecular weight cut-off of 3 kDa leading to a metabolic phase (>3 kDa) and a neurotoxic fraction (octopus saliva might be used among conspecifics for defense and for reduction of competition. Bioguided separation of the neurotoxic fraction by chromatography led to a paralysis fraction and a relaxing fraction. The paralyzing activity of the saliva was exerted by amino acids, while the relaxing activity was due to the presence of serotonin. Prey-handling studies revealed that O. maya punctures the eye or arthrodial membrane when predating blue crabs and uses the radula to bore through crown conch shells; these differing strategies may help O. maya to reduce the time needed to handle its prey.

  15. Endothelial Nitric Oxide Synthase Haplotypes Are Associated with Preeclampsia in Maya Mestizo Women

    Directory of Open Access Journals (Sweden)

    Lizbeth Díaz-Olguín

    2011-01-01

    Full Text Available Preeclampsia is a specific disease of pregnancy and believed to have a genetic component. The aim of this study was to investigate if three polymorphisms in eNOS or their haplotypes are associated with preeclampsia in Maya mestizo women.

  16. Cultural Teaching: The Development of Teaching Skills in Maya Sibling Interactions.

    Science.gov (United States)

    Maynard, Ashley E.

    2002-01-01

    Examined the development of teaching skills in older siblings responsible for teaching their younger siblings to become competent members of their culture among children from a Zinacantec Maya village in Chiapas, Mexico. Found that by age 4, children took responsibility for initiating teaching situations with their younger siblings, and by 8,…

  17. Use of marine robot`MAYA` for monitoring the Zuari and Mandovi esturine systems

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas, A.A; Afzulpurkar, S.; Navelkar, G.S.; Maurya, P.K.; Fernandes, L.; Desa, E.S.; Madhan, R.; Shenoy, D.; Kurian, S.; Naik, H.; Nagvekar, S.; Vimalakumari, D.; Dalvi, H.S.; Manoharan, V.; deAraujo, B.A; Lamani, V.; Naik, N.; Mohan, N.; Dias, Albertina; Dias, A

    to study the spatial distribution of biogeochemical properties in the Zuari and Mandovi Estuarine systems during the onset of tides. MAYA was repurposed as an ASV to tightly follow a path (Maurya, P et al., 2008) along the mid-section of the rivers...

  18. Elements of success in cooperatives conformed by Maya women in the Yucatan Peninsula, Mexico

    NARCIS (Netherlands)

    Osorio Vazqez, Maria Cristina; Bressers, Johannes T.A.; Franco Garcia, Maria Laura; Boer, C.L.; Reyes Maya, Oscar Ivan

    2016-01-01

    This paper describes different elements leading to the success of cooperatives formed by indigenous Maya women of the Yucatan Peninsula in Mexico. These elements have shown to facilitate the sustainability (permanence over time) of the cooperatives and their presence in the market, while improving

  19. Critical Pedagogy in HIV-AIDS Education for a Maya Immigrant Community

    Science.gov (United States)

    Schoorman, Dilys; Acosta, Maria Cristina; Sena, Rachel; Baxley, Traci

    2012-01-01

    In this article the authors discuss how the perspectives of Paulo Freire were instructive in addressing the challenges of HIV-AIDS education in Guatemalan Maya immigrant communities with minimal formal education and literacy. The forging of a community-based, collaborative, educational program offers several implications for effective teaching and…

  20. Human and natural impacts on fluvial and karst depressions of the Maya Lowlands

    Science.gov (United States)

    Beach, Timothy; Luzzadder-Beach, Sheryl; Dunning, Nicholas; Cook, Duncan

    2008-10-01

    This paper begins to differentiate the major drivers and chronology of erosion and aggradation in the fluvial and fluviokarst landscapes of the southern and central Maya Lowlands. We synthesize past research on erosion and aggradation and add new data from water, soils, radiocarbon dating, and archaeology to study the quantity, timing, and causes of aggradation in regional landscape depressions. Geomorphic findings come from many excavations across a landscape gradient from upland valleys, karst sinks, and fans into the coastal plain floodplains and depressions. Findings from water chemistry show that sources in the uplands have low quantities of dissolved ions but water in the coastal plains has high amounts of dissolved ions, often nearly saturated in calcium and sulfate. We found significant geomorphic complexity in the general trends in upland karst sinks. In a few instances, sediments preserve Late Pleistocene paleosols, buried 2-3 m, though many more have distinct middle to late Holocene paleosols, buried 1-2 m, after c. 2300 BP (Maya Early to Late Preclassic). From 2300-1100 BP (Late Preclassic to Classic Periods), the landscape aggraded from five main mechanisms: river flooding, climatic instability, accelerated erosion, ancient Maya landscape manipulation, and gypsum precipitation from a rise in a water table nearly saturated in calcium and sulfate ions. Evidence exists for two or three high magnitude floods, possibly driven by hurricanes. Moreover, lake-core and geophysical studies from the Petén Lakes region have shown high rates of deposition of silicate clays ('Maya Clays') starting and peaking during the Maya Preclassic and continuing to be high through the Late Classic. The main driver on upland karst depressions, the Petén lakes, upland valleys, and fans was accelerated soil erosion, but water table rise, probably driven by sea-level rise, was the main driver on the wetlands of the coastal plain because the aggraded sediments here are dominantly

  1. The global financial crisis and neighborhood decline

    NARCIS (Netherlands)

    Zwiers, Merle; Bolt, Gideon; Van Ham, Maarten; Van Kempen, Ronald

    2016-01-01

    Neighborhood decline is a complex and multidimensional process. National and regional variations in economic and political structures (including varieties in national welfare state arrangements), combined with differences in neighborhood history, development, and population composition, make it

  2. What Makes Clusters Decline?

    DEFF Research Database (Denmark)

    Østergaard, Christian Richter; Park, Eun Kyung

    2015-01-01

    Most studies on regional clusters focus on identifying factors and processes that make clusters grow. However, sometimes technologies and market conditions suddenly shift, and clusters decline. This paper analyses the process of decline of the wireless communication cluster in Denmark. The longit...... but being quick to withdraw in times of crisis....

  3. La legitimación de la realeza entre mayas del Preclásico Tardío. Los mascarones de El Tigre, Campeche Legitimizing royalty among Late Preclassic Maya. The masks from El Tigre-Campeche

    Directory of Open Access Journals (Sweden)

    Ernesto Vargas Pacheco

    2010-01-01

    Full Text Available En el arte monumental del periodo Clásico maya la imagen del señor ocupaba el sitio principal y todas las demás imágenes un lugar secundario. Con este trabajo se quiere demostrar que los soberanos mayas ya en el Preclásico Tardío, o desde antes, usaron la arquitectura para reproducir la topografía del universo y se sirvieron de los mascarones para transmitir la condición divina de sus antepasados, de sus dioses y la suya propia. En El Tigre, Campeche, se han explorado varios mascarones de estuco del Preclásico Tardío, que representan rostros humanos, los cuales bien podrían identificarse como ancestros: antepasados de gobernantes que pretenden divinizarlos para así legitimizar la realeza maya.The images of Maya dignitaries take the most important places in monumental art during Classic period, and all other representations occupy a secondary position in that context. This paper pretends to demonstrate that Maya kings tried to duplicate their conception of the Universe on civic architecture since Preclassic period, or even before; they used huge mask representations to transmit the sacred condition of their ancestors, their gods and their selves. At El Tigre site, in Campeche, have been explored several stucco masks of Late Preclassic date, showing human faces that may represent ancestors of the kings who tried to deify them in order to legitimate Maya royalty.

  4. Decline in Performance of Biochemical Reactors for Sulphate Removal from Mine-Influenced Water is Accompanied by Changes in Organic Matter Characteristics and Microbial Population Composition

    Directory of Open Access Journals (Sweden)

    Parissa Mirjafari

    2016-03-01

    Full Text Available Successful long-term bioremediation of mining-influenced water using complex organic matter and naturally-occurring microorganisms in sub-surface flow constructed wetlands requires a balance between easily and more slowly degrading material. This can be achieved by combining different types of organic materials. To provide guidance on what mixture combinations to use, information is needed on how the ratio of labile to recalcitrant components affects the degradation rate and the types of microbial populations supported. To investigate this, different ratios of wood and hay were used in up-flow column bioreactors treating selenium- and sulphate-containing synthetic mine-influenced water. The degradation rates of crude fibre components appeared to be similar regardless of the relative amounts of wood and hay. However, the nature of the degradation products might have differed in that those produced in the hay-rich bioreactors were more biodegradable and supported high sulphate-reduction rates. Microorganisms in the sulphate-reducing and cellulose-degrading inocula persisted in the bioreactors indicating that bio-augmentation was effective. There was a shift in microbial community composition over time suggesting that different microbial groups were involved in decomposition of more recalcitrant material. When dissolved organic carbon (DOC was over-supplied, the relative abundance of sulphate-reducers was low even through high sulphate-reduction rates were achieved. As DOC diminished, sulphate-reducers become more prevalent and their relative abundance correlated with sulphate concentrations rather than sulphate-reduction rate.

  5. a Review of Late Holocene Fluvial Systems in the Karst Maya Lowlands with Focus on the Rio Bravo, Belize

    Science.gov (United States)

    Beach, T.; Luzzadder-Beach, S.; Krause, S.; Doyle, C.

    2015-12-01

    The Maya Lowlands is mostly an internally draining karst region with about 400 m of regional relief. Fluvial and fluviokarst systems drain the edges of this landscape either from low limestone uplands or igneous and metamorphic complexes. Thus far most fluvial research has focused around archaeology projects, and here we review the extant research conducted across the region and new research on the transboundary Rio Bravo watershed of Belize and Guatemala. The Rio Bravo drains a largely old growth tropical forest today, but was partly deforested around ancient Maya cities and farms from 3,000 to 1000 BP. Several studies estimate that 30 to 40 percent of forest survived through the Maya period. Work here has focused on soils and sediment movement along slope catenas, in floodplain sites, and on contributions from groundwater with high dissolved loads of sulfate and calcium. We review radiocarbon dates and present new dates and soil stratigraphy from these sequences to date slope and floodplain movement, and we estimate ancient land use from carbon isotopic and pollen evidence. Aggradation in this watershed occurred by flooding, gypsum precipitation, upland erosion, and ancient Maya canal building and filling for wetland farming. Soil erosion and aggradation started at least by 3,000 BP and continued through the ancient Maya period, though reduced locally by soil conservation, post urban construction, and source reduction, especially in Maya Classic period from 1700 to 1000 BP.

  6. Mortality Reduction, Fertility Decline, and Population Growth: Toward a More Relevant Assessment of the Relationships among Them. World Bank Staff Working Papers No. 686 and Population and Development Series No. 11.

    Science.gov (United States)

    Gwatkin, Davidson

    One of a special series on population change and development, this paper focuses primarily on the programs and policies responsible for mortality or fertility change, rather than on the growth impact of a mortality or fertility change per se. The first portion of the document examines three models for assessing the population growth implications…

  7. The decline of the impetigo epidemic caused by the epidemic European fusidic acid-resistant impetigo clone: an 11.5-year population-based incidence study from a community in Western Norway.

    Science.gov (United States)

    Rørtveit, Sverre; Skutlaberg, Dag Harald; Langeland, Nina; Rortveit, Guri

    2014-12-01

    From around the year 2000, Northern Europe experienced a rise in impetigo caused by Staphylococcus aureus resistant to fusidic acid. A single clone of S. aureus was found to be the bacterial pathogen involved in the impetigo outbreak in Norway, Sweden, the UK and Ireland, termed 'the epidemic European fusidic acid-resistant impetigo clone' (EEFIC). We have followed the incidence of impetigo during the years 2001-2012 based on all patients in general practice in the island community of Austevoll, Western Norway. We previously reported a marked decline of impetigo incidence in Austevoll, from 0.0260 cases per person-year in 2002 to 0.0038 in 2009. This article explores indications of an end to the impetigo epidemic caused by the EEFIC clone. All four general practitioners (GPs) in the community (mean population = 4400) were asked to diagnose impetigo in a uniform way and to take bacterial specimens from all impetigo cases. Phenotypic characteristics of specimen bacteria were determined for the whole period and molecular analyses were performed on isolates in the period 2008-2012. We observed a further decline in incidence of impetigo in Austevoll in the study period. The proportion of fusidic acid-resistant S. aureus isolates decreased during the period 2002-2012, with a mean of 80% in the epidemic years of 2002-2004, 55% in 2005-2009, and 6% in 2010-2012. In total, 44 S. aureus isolates from impetigo were subject to molecular analyses in the period 2008-2012, and 11 were found to be related to the EEFIC. All EEFIC isolates were found in 2008-2009, with no new isolates in 2010-2012. There is an apparent end to the impetigo epidemic related to the EEFIC in this population in Western Norway.

  8. Cardiovascular Prevention of Cognitive Decline

    Directory of Open Access Journals (Sweden)

    Jean-Jacques Monsuez

    2011-01-01

    Full Text Available Midlife cardiovascular risk factors, including diabetes, hypertension, dyslipemia, and an unhealthy lifestyle, have been linked to subsequent incidence, delay of onset, and progression rate of Alzheimer disease and vascular dementia. Conversely, optimal treatment of cardiovascular risk factors prevents and slows down age-related cognitive disorders. The impact of antihypertensive therapy on cognitive outcome in patients with hypertension was assessed in large trials which demonstrated a reduction in progression of MRI white matter hyperintensities, in cognitive decline and in incidence of dementia. Large-scale database correlated statin use and reduction in the incidence of dementia, mainly in patients with documented atherosclerosis, but clinical trials failed to reach similar conclusions. Whether a multitargeted intervention would substantially improve protection, quality of life, and reduce medical cost expenditures in patients with lower risk profile has not been ascertained. This would require appropriately designed trials targeting large populations and focusing on cognitive decline as a primary outcome endpoint.

  9. ROBUST DECLINE CURVE ANALYSIS

    Directory of Open Access Journals (Sweden)

    Sutawanir Darwis

    2012-05-01

    Full Text Available Empirical decline curve analysis of oil production data gives reasonable answer in hyperbolic type curves situations; however the methodology has limitations in fitting real historical production data in present of unusual observations due to the effect of the treatment to the well in order to increase production capacity. The development ofrobust least squares offers new possibilities in better fitting production data using declinecurve analysis by down weighting the unusual observations. This paper proposes a robustleast squares fitting lmRobMM approach to estimate the decline rate of daily production data and compares the results with reservoir simulation results. For case study, we usethe oil production data at TBA Field West Java. The results demonstrated that theapproach is suitable for decline curve fitting and offers a new insight in decline curve analysis in the present of unusual observations.

  10. US Historic Declination Calculator

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This programs derives a table of secular change in magnetic declination for a specified point in the conterminous United States. It utilizes the USD polynomial and...

  11. Elements of success in cooperatives conformed by Maya women in the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Maria Cristina Osorio Vázquez

    2016-05-01

    Full Text Available This paper describes different elements leading to the success of cooperatives formed by indigenous Maya women of the Yucatan Peninsula in Mexico. These elements have shown to facilitate the sustainability (permanence over time of the cooperatives and their presence in the market, while improving the work environment and enhancing the practice of honesty. All these elements have generated an increase in the number of clients and beneficiaries due to their trustable relationships. As can be appreciated in this study, indigenous Maya women living in the Yucatan Peninsula are demonstrating an innovative way to do business, which has resulted in greater social benefits and profitability through social capital, ethical leadership and monitoring of actions.

  12. Justicia indígena maya en el sureste de México

    Directory of Open Access Journals (Sweden)

    Juana Luisa Ríos Zamudio

    2011-01-01

    Full Text Available A más de diez años de haberse implementado en Quintana Roo, México, un sistema de justicia propio para las comunidades mayas de la entidad, y pese a lo acelerado de su crecimiento y arraigo, su estructura, funcionamiento y principios éticos que lo rigen han sido poco estudiados. Este trabajo tiene como objetivo analizar su funcionamiento desde la sociología jurídica, tomando como base las constancias de actuación de los jueces tradicionales. Se podrá ver que gracias a su polivalente actuación, los jueces tradicionales son hoy una figura socialmente legitimada al interior de las comunidades mayas, aun habiendo sido creada e implementada "desde fuera" por las autoridades estatales hace apenas poco más de una década.

  13. Epilithic and endolithic bacterial communities in limestone from a Maya archaeological site.

    Science.gov (United States)

    McNamara, Christopher J; Perry, Thomas D; Bearce, Kristen A; Hernandez-Duque, Guillermo; Mitchell, Ralph

    2006-01-01

    Biodeterioration of archaeological sites and historic buildings is a major concern for conservators, archaeologists, and scientists involved in preservation of the world's cultural heritage. The Maya archaeological sites in southern Mexico, some of the most important cultural artifacts in the Western Hemisphere, are constructed of limestone. High temperature and humidity have resulted in substantial microbial growth on stone surfaces at many of the sites. Despite the porous nature of limestone and the common occurrence of endolithic microorganisms in many habitats, little is known about the microbial flora living inside the stone. We found a large endolithic bacterial community in limestone from the interior of the Maya archaeological site Ek' Balam. Analysis of 16S rDNA clones demonstrated disparate communities (endolithic: >80% Actinobacteria, Acidobacteria, and Low GC Firmicutes; epilithic: >50% Proteobacteria). The presence of differing epilithic and endolithic bacterial communities may be a significant factor for conservation of stone cultural heritage materials and quantitative prediction of carbonate weathering.

  14. IMPRISONMENT AS A RESULT OF WOMEN SUBORDINATION 194 REFLECTED IN MAYA ANGELOU‘S POEMS

    Directory of Open Access Journals (Sweden)

    Fatikha Amalina

    2017-12-01

    Full Text Available This research is aimed to describe the imprisonment of African American people, especially women, in the case of patriarchy and women subordination through Maya Angelou‘s selected poems entitled ―Caged Bird‖, ―Still I Rise‖ and ―Woman Work‖. This research discusses the meaning behind the poems that reflected Maya Angelou‘s life experience relating to women subordination and freedom. Feminism approach is applied to analyze the concept of freedom in women subordination and patriarchy in this research. The paper points to how the concept of gender intertwines with labor, ethnics, kinship and gender domination. Without aiming to paint a detailed picture of feminism, the paper explores how ideas developed in these inquiries question the taken-for-granted assumption about the universality of women‘s subordination and challenge the emancipation prerequisite of feminist agenda.

  15. Early Middle Formative Occupation in the Central Maya Lowlands: Recent Evidence from Cahal Pech, Belize

    Directory of Open Access Journals (Sweden)

    Jaime Awe

    1990-11-01

    Full Text Available After more than half a century of intensive archaeological research the early Middle Formative (or Middle Preclassic period (1000-600 B.C. continues to be one of the most enigmatic eras in the study of Lowland Maya prehistory. While several factors contribte to this situation, the primary cause for this obscurity lies in the fact that few sites have produced either contextual or stratigraphic evidence of occupation during this phase (Rice 1976; Andrews 1988. Concsequently, any new site with evidence of Middle Formative occupation can contribute substantially to our limited knowledge of this pioneering stage of the lowland Maya. This paper introduces one such site, Cahal Pech, where recent investigations have uncovered a stratigraphic sequence that tentatively spans the early Middle Formative to the Late Classic period. It provides a preliminary description, of the site's early Middle Formative configuration and briefly discusses its possible regional affiliation.

  16. Putting Us on the Map: Remote Sensing Investigation of the Ancient Maya Landscape

    Science.gov (United States)

    Sever, Thomas L.; Saturno, William

    2004-01-01

    A common problem for archaeologists studying ancient settlement in the Maya Lowlands is overcoming the dense vegetation in order to obtain an accurate regional perspective of the presence of archaeological sites, their exact locations and their overall extents. Most often this is done by extensive ground surveys in which many individuals chop parallel paths through the vegetation in search of sites. Once a site is found an effort is made to mark its location on a regional map and to explore its perimeter. Obtaining locational information has been made dramatically easier in recent years with the advent of improved Global Positioning Systems (GPS), however the process of initial identification of sites and the determination of their borders is exceedingly labor intensive and has remained relatively unchanged since the beginning of settlement surveys in the region in the 1950 s. Currently, we are revolutionizing settlement survey in the Maya Lowlands by using remotely sensed data from IKONOS, Quickbird, and Eo 1, satellites as well as airborne AIRSAR radar data. The Ancient Maya built their cities, towns and even their smallest hamlets using excavated limestone and lime plasters. We propose that the decay of these structures provides a unique microenvironment for the growth of vegetation as the levels of moisture and nutrition within the ruins vary substantially from those in the surrounding forest. These microenvironmental differences on the ground are likewise represented by compositional differences in the forest canopy both in the species present and in leaf color (representing moisture/nutritional stress) visible through the analysis of high-resolution satellite data. In this way the detailed analysis of forest composition can reveal a detailed picture of the ancient settlements that lie beneath it. Preliminary examinations using this technique have been very successful and we are refining these techniques in order to efficiently comprehend the details of

  17. Dietetic determinants of zinc consumption in stunted children under five in maya communities from Guatemala

    OpenAIRE

    Monroy-Valle, Michele; Universidad Rafael Landívar, Facultad de Ciencias de la Salud, Licenciatura en Nutrición Universidad de San Carlos de Guatemala, Facultad de Ciencias Químicas y Farmacia, Unidad de Estadística, Epidemiología y Salud Pública; Coyoy, Wendy; Universidad Rafael Landívar, Facultad de Ciencias de la Salud, Licenciatura en Nutrición; De León, Jorge; Universidad de San Carlos de Guatemala, Facultad de Ciencias Químicas y Farmacia, Unidad de Estadística, Epidemiología y Salud Pública; Flórez, Iván D.; Departamento de Pediatría y Puericultura, Universidad de Antioquia, Medellín, Colombia; Department of Clinical Epidemiology & Biostatistics, McMaster University, Hamilton, Canada.

    2017-01-01

    The objective of the study was to identify the elements from feeding patterns that influence the intake and bioavailability of zinc in stunted children (SC) 1-5 years from Maya communities living in Huehuetenango, Guatemala. This descriptive, cross-sectional study was performed in 138 stunted children aged 1-5 years. It was applied: an inventory of zinc food sources availability, a Food Frequency Questionnaire, a questionnaire about living conditions. anthropometrics measurements and informat...

  18. Perlindungan Merek Terdaftar Dari Kejahatan Dunia Maya Melalui Pembatasan Pendaftaran Nama Domain

    Directory of Open Access Journals (Sweden)

    Setia Dharma

    2015-05-01

    Full Text Available Abstract: The Protection of Registered Trademark of Cyber Crime Through The Restriction of The Domain Name Registration. The progress of science and technology has implications for the progress of the current trading method. It is not only done conventionally but also carried out through cyberspace. Trading in the virtual world requires the use of a domain name (cyber squatting as a differentiator between one company with other companies. Law No. 11 Year 2008 on Information and Electronic Transactions regulate the use of domain names and emphasize the element of good faith in the implementation. In practice, there is a breach of the domain name registration is a crime which is the trademark or name that has a commercial value. This paper is going to examine aspects of protection-registered trademark of cyber crime through the restriction of the domain name registration and implementation of good faith. Abstrak: Perlindungan Merek Terdaftar Dari Kejahatan Dunia Maya Melalui Pembatasan Pendaftaran Nama Domain. Kemajuan ilmu dan teknologi membawa implikasi pada kemajuan metode perdagangan yang saat ini bukan hanya dilakukan secara konvensional, namun juga dilakukan melalui dunia maya. Perdagangan dalam dunia maya mensyaratkan penggunaan nama domain (cyber squatting sebagai pembeda antara satu perusahaan dengan perusahaan yang lainnya. Undang-Undang No. 11 Tahun 2008 Tentang Informasi dan Transaksi elektronik mengatur penggunaan nama domain tersebut dan menekankan unsur iktikad baik dalam pelaksanaannya. Prakteknya, terdapat pelanggaran nama domain tersebut yang merupakan merupakan kejahatan pendaftaran merek dagang atau nama yang memiliki nilai komersial. Tulisan ini hendak mengkaji aspek perlindungan merek terdaftar dari kejahatan dunia maya melalui pembatasan pendaftaran nama domain dan pelaksanaan iktikad baik. DOI: 10.15408/jch.v1i2.1463

  19. Does the Maya Forest Need More Roads?:Conservation Policy in Brief

    OpenAIRE

    Conde, Dalia Amor; Ramos, Victor Hugo; Burgués, Irene; Castellanos, Bayron; Fleck, Leonardo; Albacete, Carlos; Espinoza, Piedad; Manterola, Carlos; Paiz, Gerardo

    2007-01-01

    An assortment of road projects has been proposed in the border region of Mexico, Guatemala and Belize, which is part of the Maya Forest, the largest contiguous tropical forest in the Americas north of the Amazon. The proposals are apparently aimed at spurring economic growth and reducing the high levels of poverty found in this area. But more and better roads usually bring more people and expand farms. Decision-makers are therefore confronted with a seeming conflict between conservation and d...

  20. Beyond Nature Appropriation: Towards Post-development Conservation in the Maya Forest

    OpenAIRE

    Jose E Martinez-Reyes

    2014-01-01

    The establishment of biosphere reserves in Mexico was followed by alternative livelihood conservation/development projects to integrate indigenous groups into Western style conservation under the idea of sustainable development and participation. In this paper, I discuss the outcomes of two forest wildlife management projects in one Maya community along the Sian Ka′an Biosphere Reserve in the state of Quintana Roo. Both projects ultimately failed and the community mobilised and expelled the N...

  1. Putting us on the Map: Remote Sensing Investigation of the Ancient Maya Landscape

    Science.gov (United States)

    Sever, Thomas L.; Saturno, William; Irwin, Daniel E.

    2004-01-01

    A common problem for archaeologists studying ancient settlement in the Maya Lowlands is overcoming the dense vegetation in order to obtain an accurate regional perspective of the presence of archaeological sites, their exact locations and their overall extents. Most often this is done by extensive ground surveys in which many individuals chop parallel paths through the vegetation in search of sites. Once a site is found an effort is made to mark its location on a regional map and to explore its perimeter. Obtaining locational information has been made dramatically easier in recent years with the advent of improved Global Positioning Systems (GPS), however the process of initial identification of sites and the determination of their borders is exceedingly labor intensive and has remained relatively unchanged since the beginning of settlement surveys in the region in the 1950's. Currently, we are revolutionizing settlement survey in the Maya Lowlands by using remotely sensed data from IKONOS, Quickbird, and Eol, satellites. The Ancient Maya built their cities, towns and even their smallest hamlets using excavated limestone and lime plasters. We propose that the decay of these structures provides a unique microenvironment for the growth of vegetation as the levels of moisture and nutrition within the ruins vary substantially from those in the surrounding forest. These microenvironmental differences on the ground are likewise represented by compositional differences in the forest canopy both in the species present and in leaf color (representing moisture/nutritional stress) visible through the analysis of high- resolution satellite data. In this way the detailed analysis of forest composition can reveal a detailed picture of the ancient settlements that lie beneath it. Preliminary examinations using this technique have been very successful and we are refining these techniques in order to efficiently comprehend the details of Ancient Maya settlement in the Lowlands.

  2. Politics in the Western Maya Region (I: Ajawil/Ajawlel and Ch'e'n

    Directory of Open Access Journals (Sweden)

    Péter Bíró

    2011-01-01

    Full Text Available In a series of articles I reflect on the use of various expressions which are connected to what we call the political in the inscriptions of the Classic Maya Western Region. These words express concepts which help to understand the intricate details of the interactions between the political entities and their internal organisations in the Classic Maya Lowlands. Words such as 7ajawil, 7ajawlel, the kennings built on the base of ch'e7n (cave, pond, the emblem glyphs and titles will be examined in light of what they tell us about the functioning of the political organisation of the Classic Period in a constrained region.En una serie de artículos como éste investigo el uso de varias palabras en las inscripciones mayas de la época Clásica de la Región Occidental vinculadas con lo que nosotros llamamos "política". Estas palabras expresan conceptos que ayudan a entender los matices de las relaciones entre las entidades políticas de las Tierras Bajas Mayas y su organización interna. Términos como ajaw'ü I ajawlel, los difrasismos con base ch'e'n (cueva, pozo, los glifos emblemas y los títulos serán examinados tomando en cuenta la información que nos proporcionan sobre el funcionamiento de la organización política de la época Clásica en una región restringida.

  3. BIOTIC FACTORS IN AMPHIBIAN POPULATION DECLINES

    Science.gov (United States)

    Amphibians evolved in, and continue to exist in, habitats that are replete with many other organisms. Some of these organisms serve as prey for amphibians and others interact with amphibians as predators, competitors, pathogens, or symbionts. Still other organisms in their enviro...

  4. Guatemala paleoseismicity: from Late Classic Maya collapse to recent fault creep

    Science.gov (United States)

    Brocard, Gilles; Anselmetti, Flavio S.; Teyssier, Christian

    2016-11-01

    We combine ‘on-fault’ trench observations of slip on the Polochic fault (North America-Caribbean plate boundary) with a 1200 years-long ‘near-fault’ record of seismo-turbidite generation in a lake located within 2 km of the fault. The lake record indicates that, over the past 12 centuries, 10 earthquakes reaching ground-shaking intensities ≥ VI generated seismo-turbidites in the lake. Seismic activity was highly unevenly distributed over time and noticeably includes a cluster of earthquakes spread over a century at the end of the Classic Maya period. This cluster may have contributed to the piecemeal collapse of the Classic Maya civilization in this wet, mountainous southern part of the Maya realm. On-fault observations within 7 km of the lake show that soils formed between 1665 and 1813 CE were displaced by the Polochic fault during a long period of seismic quiescence, from 1450 to 1976 CE. Displacement on the Polochic fault during at least the last 480 years included a component of slip that was aseismic, or associated with very light seismicity (magnitude 1 ky) punctuated by destructive earthquake clusters.

  5. Modern tree species composition reflects ancient Maya "forest gardens" in northwest Belize.

    Science.gov (United States)

    Ross, Nanci J

    2011-01-01

    Ecology and ethnobotany were integrated to assess the impact of ancient Maya tree-dominated home gardens (i.e., "forest gardens"), which contained a diversity of tree species used for daily household needs, on the modern tree species composition of a Mesoamerican forest. Researchers have argued that the ubiquity of these ancient gardens throughout Mesoamerica led to the dominance of species useful to Maya in the contemporary forest, but this pattern may be localized depending on ancient land use. The tested hypothesis was that species composition would be significantly different between areas of dense ancient residential structures (high density) and areas of little or no ancient settlement (low density). Sixty-three 400-m2 plots (31 high density and 32 low density) were censused around the El Pilar Archaeological Reserve in northwestern Belize. Species composition was significantly different, with higher abundances of commonly utilized "forest garden" species still persisting in high-density forest areas despite centuries of abandonment. Subsequent edaphic analyses only explained 5% of the species composition differences. This research provides data on the long-term impacts of Maya forests gardens for use in development of future conservation models. For Mesoamerican conservation programs to work, we must understand the complex ecological and social interactions within an ecosystem that developed in intimate association with humans.

  6. Decline and conservation of bumble bees.

    Science.gov (United States)

    Goulson, D; Lye, G C; Darvill, B

    2008-01-01

    Declines in bumble bee species in the past 60 years are well documented in Europe, where they are driven primarily by habitat loss and declines in floral abundance and diversity resulting from agricultural intensification. Impacts of habitat degradation and fragmentation are likely to be compounded by the social nature of bumble bees and their largely monogamous breeding system, which renders their effective population size low. Hence, populations are susceptible to stochastic extinction events and inbreeding. In North America, catastrophic declines of some bumble bee species since the 1990s are probably attributable to the accidental introduction of a nonnative parasite from Europe, a result of global trade in domesticated bumble bee colonies used for pollination of greenhouse crops. Given the importance of bumble bees as pollinators of crops and wildflowers, steps must be taken to prevent further declines. Suggested measures include tight regulation of commercial bumble bee use and targeted use of environmentally comparable schemes to enhance floristic diversity in agricultural landscapes.

  7. Maize dependence or market integration? Caries prevalence among indigenous Maya communities with maize-based versus globalized economies.

    Science.gov (United States)

    Vega Lizama, Elma Maria; Cucina, Andrea

    2014-02-01

    The relationship between diet and oral health is widely known, yet data on dental caries prevalence is lacking for many indigenous groups with traditional or rapidly modernizing diets. This research documents caries prevalence in two Maya communities from northern Yucatán (Mexico) with significantly different levels of market integration, subsistence, and diet: Yalsihón, with a traditional, maize-based subsistence economy, and Dzilam, with access to globalized food markets. Each sample was subdivided by sex into 15-19, 20-24, and 25-30 years-of-age classes. Caries prevalence was considered separately both when the lesion affected the enamel superficially (grade 1+) and when it reached the dentin (grade 2+). In both villages, females of all age classes manifest more caries than males. Results show higher prevalence of caries at Dzilam than at Yalsihón, except for grade 1+ caries among 15-19-year-old males and grade 2+ caries among 15-19-year-old females. Though differences are not significant, earlier pregnancies among 15-19-year-old females at Yalsihón could be a causative factor. A survey indicated a more balanced diet at Yalsihón despite a heavier intake of maize than at Dzilam. Striking differences were documented in the ingestion of soda and globalized foods; sodas were virtually absent at Yalsihón, while at Dzilam they were ingested daily in great quantities. The decline in oral health at Dzilam is inferred to result from consumption of industrially processed foods and drinks, while a traditional diet leads to less caries despite daily heavy consumption of maize, which must be considered when interpreting caries rates in archaeological samples. Copyright © 2013 Wiley Periodicals, Inc.

  8. La realidad comunicable como discurso histórico decimonónico:los indígenas mayas durante la guerra de castas en Yucatán

    Directory of Open Access Journals (Sweden)

    Miriam Edith León Méndez

    2017-12-01

    Full Text Available This study focuses on the historical discourse in 4 books by Justo Sierra O ́Reilly, Serapio Baqueiro and Eligio Ancona. leading historians in the XIX centuryo Yucatan Peninsula. We aim to understand the use of the adjective bárbaro (“barbarian”, to refer to native Mayan people partaking in The Caste War, a conflict that developed in the Yucatan. Thisanalysis is performed within the historiographical methodology to account for the fact that the comunicable reality about the native Maya, described as barbarian, is the main connotation identifying this population as outcasts with respect to the sociopolitical and cultural norms of their time.

  9. Forest decline through radioactivity

    International Nuclear Information System (INIS)

    Reichelt, G.; Kollert, R.

    1985-01-01

    Is more serious damage of forest observed in the vicinity of nuclear reactors. How are those decline patterns to be explained. Does the combined effect of radioactivity and different air pollutants (such as nitrogen oxides, sulfur dioxide, oxidants etc.) have an influence in the decline of the forest. In what way do synergisms, i.e. mutually enhanced effects, participate. How does natural and artificial radioactivity affect the chemistry of air in the polluted atmosphere. What does this mean for the extension of nuclear energy, especially for the reprocessing plant planned. Damage in the forests near nuclear and industrial plants was mapped and the resulting hypotheses on possible emittors were statistically verified. Quantitative calculations as to the connection between nuclear energy and forest decline were carried through: they demand action. (orig./HP) [de

  10. Cluster Decline and Resilience

    DEFF Research Database (Denmark)

    Østergaard, Christian Richter; Park, Eun Kyung

    Most studies on regional clusters focus on identifying factors and processes that make clusters grow. However, sometimes technologies and market conditions suddenly shift, and clusters decline. This paper analyses the process of decline of the wireless communication cluster in Denmark, 1963......-2011. Our longitudinal study reveals that technological lock-in and exit of key firms have contributed to impairment of the cluster’s resilience in adapting to disruptions. Entrepreneurship has a positive effect on cluster resilience, while multinational companies have contradicting effects by bringing...... in new resources to the cluster but being quick to withdraw in times of crisis....

  11. Two Holocene paleofire records from Peten, Guatemala: Implications for natural fire regime and prehispanic Maya land use

    Science.gov (United States)

    Anderson, Lysanna; Wahl, David

    2016-03-01

    Although fire was arguably the primary tool used by the Maya to alter the landscape and extract resources, little attention has been paid to biomass burning in paleoenvironmental reconstructions from the Maya lowlands. Here we report two new well-dated, high-resolution records of biomass burning based on analysis of macroscopic fossil charcoal recovered from lacustrine sediment cores. The records extend from the early Holocene, through the full arc of Maya prehistory, the Colonial, and post-Colonial periods ( 9000 cal yr BP to the present). (Hereafter BP) The study sites, Lago Paixban and Lago Puerto Arturo, are located in northern Peten, Guatemala. Results provide the first quantitative analysis from the region demonstrating that frequent fires have occurred in the closed canopy forests since at least the early Holocene ( 9000 BP), prior to occupation by sedentary agriculturalists. Following the arrival of agriculture around 4600 BP, the system transitioned from climate controlled to anthropogenic control. During the Maya period, changes in fire regime are muted and do not appear to be driven by changes in climate conditions. Low charcoal influx and fire frequency in the Earliest Preclassic period suggest that land use strategies may have included intensive agriculture much earlier than previously thought. Preliminary results showing concentrations of soot/black-carbon during the middle and late Preclassic periods are lower than modern background values, providing intriguing implications regarding the efficiency of Maya fuel consumption.

  12. Two Holocene paleofire records from Peten, Guatemala: Implications for natural fire regime and prehispanic Maya land use

    Science.gov (United States)

    Anderson, Lysanna; Wahl, David B.

    2016-01-01

    Although fire was arguably the primary tool used by the Maya to alter the landscape and extract resources, little attention has been paid to biomass burning in paleoenvironmental reconstructions from the Maya lowlands. Here we report two new well-dated, high-resolution records of biomass burning based on analysis of macroscopic fossil charcoal recovered from lacustrine sediment cores. The records extend from the early Holocene, through the full arc of Maya prehistory, the Colonial, and post-Colonial periods (~ 9000 cal yr BP to the present). (Hereafter BP) The study sites, Lago Paixban and Lago Puerto Arturo, are located in northern Peten, Guatemala. Results provide the first quantitative analysis from the region demonstrating that frequent fires have occurred in the closed canopy forests since at least the early Holocene (~ 9000 BP), prior to occupation by sedentary agriculturalists. Following the arrival of agriculture around 4600 BP, the system transitioned from climate controlled to anthropogenic control. During the Maya period, changes in fire regime are muted and do not appear to be driven by changes in climate conditions. Low charcoal influx and fire frequency in the Earliest Preclassic period suggest that land use strategies may have included intensive agriculture much earlier than previously thought. Preliminary results showing concentrations of soot/black-carbon during the middle and late Preclassic periods are lower than modern background values, providing intriguing implications regarding the efficiency of Maya fuel consumption.

  13. Is the onset of the 6th century 'dark age' in Maya history related to explosive volcanism?

    Science.gov (United States)

    Nooren, Kees; Hoek, Wim Z.; Van der Plicht, Hans; Sigl, Michael; Galop, Didier; Torrescano-Valle, Nuria; Islebe, Gerald; Huizinga, Annika; Winkels, Tim; Middelkoop, Hans; Van Bergen, Manfred

    2016-04-01

    Maya societies in Southern Mexico, Guatemala and Belize experienced a 'dark age' during the second half of the 6th century. This period, also known as the 'Maya Hiatus', is characterized by cultural downturn, political instability and abandonment of many sites in the Central Maya Lowlands. Many theories have been postulated to explain the occurrence of this 'dark age' in Maya history. A possible key role of a large volcanic eruption in the onset of this 'dark age' will be discussed. Volcanic deposits recovered from the sedimentary archive of lake Tuspán and the Usumacinta-Grijalva delta were studied in detail and the combination of multiple dating techniques allowed the reconstruction of the timing of a large 6th century eruption. Volcanic glass shards were fingerprinted to indicate the source volcano and high resolution pollen records were constructed to indicate the environmental impact of the eruption. Results are compared with available archaeological data and causality with the disruption of Maya civilization will be evaluated.

  14. Decline and infiltrated lung

    International Nuclear Information System (INIS)

    Giraldo Estrada, Horacio; Arboleda Casas, Felipe; Duarte, Monica; Triana Harker, Ricardo

    2001-01-01

    The paper describes the decline and infiltrated lung in a patient of 45 years, with diagnosis of arthritis rheumatoid from the 43 years, asymptomatic, without treatment, married, of the 15 to the 35 years of 3 to 10 cigarettes daily, she refers of 7 months of evolution episodes of moderate dyspnoea with exercises and dry cough with occasional mucous expectoration between others

  15. Las corridas de toros en los pueblos mayas orientales. Una aproximación etnográfica Bullfights at Eastern Maya Towns. An Etnographic Approach

    Directory of Open Access Journals (Sweden)

    Andrés Medina Hernández

    2010-01-01

    Full Text Available En este ensayo realizamos una descripción de las corridas de toros en los pueblos mayas del oriente de Yucatán; la intención principal es situar esta expresión festiva en el contexto de los rituales que configuran las fiestas patronales, de tal manera que se destaque un hecho central: la profunda transformación de una fiesta de claros orígenes ibéricos en una manifestación profundamente entramada con una visión del mundo de raíz mesoamericana. Un eje de análisis es el que corresponde a las nociones de sacrificio que articulan los acontecimientos en el coso taurino con los más discretos que suceden en el interior de las casas de los dirigentes de los gremios, donde el sacrificio de puercos y pavos constituye la base de una gastronomía ritual. Otro más es el reconocimiento de referentes simbólicos espaciales y temporales de raíz mesoamericana que subyacen en todo el conjunto ritual que compone estas celebraciones de los mayas peninsulares.In this essay we describe bullfighting among the Maya peoples in eastern Yucatan. The fundamental aim is to situate this festive expression in the context of the rituals that shape the patron feasts, so as to stress a central fact: the transformation of a feast of clear Iberian origin into a manifestation that is deeply intertwined with a world vision of Mesoamerican ancestry. An analytical axis corresponds to the notions of sacrifice that articulate the events inside the bullring with those more discrete, that take place within the homes of the leaders of the guilds. Here, sacrifice of turkeys and pigs constitute the basis of a ritual gastronomy. Another axis is the acknowledgement of symbolic space and time referents of Mesoamerican origin underlying, as a whole, the ritual compound in these peninsular Mayan celebrations.

  16. Carious lesions and maize consumption among the Prehispanic Maya: an analysis of a coastal community in northern Yucatan.

    Science.gov (United States)

    Cucina, Andrea; Cantillo, Cristina Perera; Sosa, Thelma Sierra; Tiesler, Vera

    2011-08-01

    Patterns of carious lesions were analyzed in the Classic period coastal Maya population of Xcambó, a salt production and administration center in northern Yucatan. To this end, the study investigated caries in the permanent dentitions of 163 adult skeletons, 23 from the Early Classic (AD 250-550) and 140 from the Late Classic period (AD 550-750), equally distributed between sexes. The archaeological and bioarchaeological evidence indicates a wealthy and socially homogeneous population dedicated to salt production and administration in the Early Classic that switched to pure administrative functions in the Late Classic. The results indicate an increase in caries from 7.4% and 21.2% (males and females respectively) from the Early Classic to 14.0% in males and 27.4% in females from the Late Classic period. The rate of caries in the Early and in the Late Classic phases of continuous occupation is not consistent with a simple interpretation of a heavier reliance on maize during the latter phase, characterized by a sedentary lifestyle, particularly for the male segment of the society now dedicated completely to the administration of the salt mines. Rather, the increase in caries rates in both sexes is best explained within a broader context of overall food habits, new cariogenic foods for both sexes, and the changes in lifestyle imposed by the increased socioeconomic role of the site. Our conclusions stress the limitations imposed by interpreting carious lesions solely in terms of single dietary components, such as maize consumption, without taking into account broader aspects of cultural and socioeconomic relevance. Copyright © 2011 Wiley-Liss, Inc.

  17. Reconstructing the role of landuse change on water yield at the Maya urban center Tikal, Guatemala [700-800 AD

    Science.gov (United States)

    Shu, L.; Duffy, C.; French, K. D.; Murtha, T., Jr.; Garcia-Gonzalez, S. E.

    2014-12-01

    In recent years scientists have been debating the role of climate on the trajectory of Maya culture in the Late Classic period, 600-900 AD. Paleo-climatologists have reconstructed realizations of climate [Haug 2003; Medina-Elizalde 2012; Hodell 1995] that offer evidence for reduced precipitation in the Late Classic period. Recently French et al [2014] proposed that landuse change may also play an important role in the available water supply at Tikal, with the removal of tropical forest and conversion to maize-agriculture and urban landuse leading to extensive development of sophisticated water storage systems and rainfall harvesting for water supply and irrigation. Rapid population growth is a concurrent and compounding factor [Scarborough 2012; Shaw 2003] where landuse impacts the distribution and availability of water storage in the surrounding watershed. Although proposed climate scenarios for the Late Classic offer a quantitative scenario for possible atmospheric conditions at Tikal, the impact of land use change on the distribution and availability of water supply has not been evaluated. In this research we reconstruct the plausible vulnerability of the water supply at Tikal under the combined forces of climatic and land use change. The Penn State Integrated Hydrologic Model (PIHM) [Qu and Duffy 2007] is used to simulate the daily-to-seasonal space and time distribution of soil moisture, groundwater and surface water storage for the period 700-800 AD, the peak of Tikal's population history. The analysis includes a quantitative assessment of the likely changes in available water storage as tropical forest is converted to maize agriculture and urban land. In particular we examine the important control that reduced canopy interception plays in the seasonal availability of water. Preliminary simulations suggest that removing tropical forest increases runoff and available water storage, which may serve to moderate seasonal and long-term drought conditions.

  18. Game Art Complete All-in-One; Learn Maya, 3ds Max, ZBrush, and Photoshop Winning Techniques

    CERN Document Server

    Gahan, Andrew

    2008-01-01

    A compilation of key chapters from the top Focal game art books available today - in the areas of Max, Maya, Photoshop, and ZBrush. The chapters provide the CG Artist with an excellent sampling of essential techniques that every 3D artist needs to create stunning game art. Game artists will be able to master the modeling, rendering, rigging, and texturing techniques they need - with advice from Focal's best and brightest authors. Artists can learn hundreds of tips, tricks and shortcuts in Max, Maya, Photoshop, ZBrush - all within the covers of one complete, inspiring reference

  19. Apicultura y organizaciones de apicultores entre los mayas de Yucatán Beekeeping and Apicultural Organizations Among the Mayas of Yucatan

    Directory of Open Access Journals (Sweden)

    Margarita Rosales González

    2010-01-01

    Full Text Available En las comunidades mayas la apicultura continúa siendo una actividad relevante pero complementaria, cuya lógica y condiciones de producción se contraponen a las nuevas normas del mercado internacional. La integración de organizaciones apícolas se considera una estrategia para la "modernización" de la apicultura y la comercialización de la miel en mejores condiciones. Este trabajo se refiere al sentido que tanto la apicultura como estas organizaciones tienen para sus integrantes, a sus expectativas, intereses, aprendizajes y a la forma en que se relacionan con instituciones y agentes externos. El escrito se basa en entrevistas y observaciones realizadas en 12 organizaciones apícolas durante 2005 y 2006 en el marco del proyecto de investigación del centro INAH Yucatán "Organizaciones indígenas y procesos de desarrollo en comunidades mayas del sur de Yucatán".In Mayan communities, beekeeping continues to be an important but complementary activity, whose logic and conditions of production are opposed to the new norms of the international market. The integration of apicultural organizations is considered as a strategy for the "modernization" of beekeeping and the commercialization of the honey in better quality. The present research deals with the meaning that beekeeping has for the members of such organizations, and it explores the expectations, interests and training processes of the members, analyzing finally how are the relationships between these organizations and external agents and institutions. The research is based on interviews and observations made in 12 apicultural organizations between 2005 and 2006, as part of the research project of the INAH Regional Center Yucatan, entitled "Indigenous Organizations and Processes of Development in Mayan Communities in Southern Yucatan".

  20. SOBRE LA EDAD DE LOS HORNOS DE CAL EN EL ÁREA MAYA (About the age of the lime kilns in the Maya area

    Directory of Open Access Journals (Sweden)

    Soledad Ortiz Ruiz

    2015-12-01

    Full Text Available La investigación que presentamos es sobre el hallazgo y la datación arqueomagnética de hornos de cal en el área maya, México. La relevancia de la datación arqueomagnética consiste en localizar las construcciones arquitectónicas y dilucidar el periodo de utilización por las sociedades que habitaron la zona de ubicación de dichas construcciones. Asumimos que se trataba de hornos prehispánicos por su asociación con el contexto de la excavación. Sin embargo, los resultados de la combinación de dataciones y métodos arqueométricos permitieron ubicar estas estructuras en distintos periodos de utilización y, por tanto, asumir la continuidad de esta tecnología productiva más allá del periodo prehispánico. Asimismo los trabajos de datación nos permiten clarificar la utilización de esta tecnología y práctica productiva en dicha zona cultural. ENGLISH: The investigation presented here is related to the discovery and archaeomagnetic dating of lime kilns in the Maya area, Mexico. The relevance of such dating is to locate architectural constructions and elucidate the period of use by societies that are responsible for their construction. We assume a prehispanic period for the kilns because of their context within the excavation. The combination of dating methods and archaeometric experiments allowed the identification of different periods of use and, therefore, suggests the persistence of this production technology beyond the prehispanic period. Dating work also allows us to clarify the use of this technology and productive practices in this cultural area.

  1. El léxico cromático y la ideología maya Chromatic lexic and Maya ideology

    Directory of Open Access Journals (Sweden)

    Sanja Savkic

    2011-01-01

    Full Text Available Para acercarse al campo semántico de los colores, de primera importancia son diversos diccionarios de las lenguas mayances. El objetivo es hacer una descripción preliminar del vocabulario cromático, compuesto de cinco términos referidos a colores básicos que en el maya yucateco se llaman sak, ek', chak, k'an y ya'ax y significan "blanco", "negro", "rojo", "amarillo" y "verde-azul", respectivamente. El mismo vocabulario remite a determinadas categorías extralingüísticas que la lengua es capaz de acumular, reflejar y comunicar. Éstas dependen de una cultura particular, por lo que el estudio se amplía con las informaciones de diferentes fuentes escritas redactadas durante la época colonial. La intención es detectar los múltiples usos que se hacían en todos los ámbitos de la vida de los colores, lo cual a su vez permite considerar estos últimos como conceptualizaciones articuladas en pares de oposición o agrupamientos tripartitos.To gain greater insight into the color semantic field, it is important to consult various Mayance language dictionaries, in order to assemble a preliminary chromatic vocabulary, composed of five basic color terms which in Yucatec Maya are sak, ek', chak, k'an and ya'ax, or "white", "black", "red", "yellow" and "green-blue", respectively. The very vocabulary addresses certain extra-linguistic categories that language is capable of accumulating, reflecting, and communicating. These categories depend on a particular culture; consequently this study is amplified with greater information from different sources written during the colonial period in order to shed light on the many uses that the colors had in the aspects of human life which, at the same time, can be seen in conceptualizations articulated in pairs of opposition or tripartite groupings.

  2. The fertility decline in Kenya.

    Science.gov (United States)

    Robinson, W C; Harbison, S F

    1995-01-01

    In Sub-Saharan Africa Kenya is a prime example of a country experiencing a rapid decline in fertility and greater contraceptive prevalence. These changes have occurred since 1980 when fertility was high at 8.0 children per woman. In 1993 the total fertility rate (TFR) was 5.4, and the growth rate declined to about 2.0%. This transition is swifter than any country in contemporary Asia or historical Europe. The likely projection for Kenya is attainment of replacement level fertility during the 2020s and a leveling of population at about 100 million persons. Fertility has declined the most in urban areas and central and eastern regions. Bongaarts' proximate determinants (TFR, total marital fertility rate, total natural marital fertility rate, and total fecundity) are reduced to the proportion of currently married women using contraception, the proportion in lactational nonfecund status, and the proportion currently married. Actual fertility change is accounted for by total fertility change of 3.0 children. Lactational infecundability accounts for 0.5 potential births, and changes in marital fertility account for 1.0 reduced births per woman. About 70% of fertility reduction is accounted for by contraception and abortion. During 1977-78 80% of fertility control was due to lactational nonfecundity, 10% to nonmarriage, and 10% to contraception. In 1993 lactational nonfecundity accounted for 50% of the reduction, nonmarriage for 20%, and abortion about 30%. Future fertility is expected to be dependent on contraceptive prevalence. Kenya has experienced the Coale paradigm of preconditions necessary for demographic transition (willing, ready, and able). High fertility in Africa is not intractable. Creating the change in attitudes that leads to readiness is linked to education, health, and exposure to modernizing media and urban lifestyles. The public sector family planning program in Kenya has created the opportunity for access and availability of contraception. The key

  3. Adaptations of a Yucatec Maya Multiple-Use Ecological Management Strategy to Ecotourism

    Directory of Open Access Journals (Sweden)

    Eduardo García-Frapolli

    2008-12-01

    Full Text Available Over the last 40 years, the Yucatan Peninsula has experienced the implementation and promotion of development programs that have economically and ecologically shaped this region of Mexico. Nowadays, tourist development has become the principal catalyst of social, economic, and ecological changes in the region. All these programs, which are based on a specialization rationale, have historically clashed with traditional Yucatec Maya management of natural resources. Using participant observation, informal and semi-structured interviews, and life-history interviews, we carried out an assessment of a Yucatec Maya natural resources management system implemented by three indigenous communities located within a natural protected area. The assessment, intended as an examination of the land-use practices and productive strategies currently implemented by households, was framed within an ecological-economic approach to ecosystems appropriation. To examine the influence of tourism on the multiple-use strategy, we contrasted productive activities among households engaged primarily in ecotourism with those more oriented toward traditional agriculture. Results show that households from these communities allocated an annual average of 586 work days to implement a total of 15 activities in five different land-use units, and that those figures vary significantly in accordance with households' productive strategy (agriculture oriented or service oriented. As the region is quickly becoming an important tourist destination and ecotourism is replacing many traditional activities, we discuss the need for a balance between traditional and alternative economic activities that will allow Yucatec Maya communities to diversify their economic options without compromising existing local management practices.

  4. Environmental and morphological changes around the Maritime Maya site Vista Alegre.

    Science.gov (United States)

    Jaijel, Roy; Goodman, Beverly; Glover, Jeffrey; Beddows, Patricia; Carter, Alice; Smith, Derek; Rissolo, Dominique; Ben Avraham, Zvi

    2016-04-01

    The untold story of the Maritime Maya from the ancient port site Vista Alegre, is being written for the first time using a multidisciplinary effort that aims to reconstruct the environmental and morphological history of the site. Vista Alegre is located on the north-eastern tip of the Yucatan peninsula, on the ancient Maritime Maya trade routes. This strategic point between the Caribbean Sea and the Gulf of Mexico, offers an ideal setting for this kind of research, which will add to the general Maritime Maya history. The multidisciplinary effort is part of a larger project called "Costa Escodida". The project's main goals are to learn how the ancient inhabitants adapted to the environment, and to understand how this coastal site was integrated into broader maritime trade routes. The portion of the research presented here concentrates on the sites geomorphology and climate during the past 2-3000 years through the multiproxy analysis of marine sediment core and surface samples combined with archaeological data. This study aids our understanding of the site's possible functions, the environmental challenges the local inhabits contended with, and the identification of ancient harboring locations. The site was inhabited from the 9th century B.C until the mid 16th century A.D., with an apparent two century abandonment phase from the mid 7th to 9th century A.D. According to the results, five depositional phases can be recognized, and the related shoreline reconstruction shows a general trend of a flooded terrestrial landscape. This 'flooding' relates well to relative sea-level curves published in the region. Continued analysis of results from the research, and future research activities, may make it possible to recognize hurricane proxies in the sediment, locate underwater manmade seafaring artifacts and facilities, determine the range of economic opportunities for past inhabitants and quantify the availability of potable water sources.

  5. "Cuando alguien habla la Maya se nota que son pobres": Narrativas de identidad de los mayas yucatecos en torno a la radiodifusora indigenista La voz de los mayas, XEPET

    Directory of Open Access Journals (Sweden)

    Inés Cornejo Portugal

    2010-06-01

    Full Text Available En este trabajo se examinan las narrativas de identidad de los receptores culturales de la radiodifusora indigenista “La Voz de los Mayas, Xepet”, respecto de su relación con la oferta radiofónica de esta emisora ubicada en la cabecera municipal de Peto, al sur de Yucatán, México. El propósito es, por un lado, sistematizar, desde el análisis argumentativo, el uso, estructura y estrategias argumentativas de los maya hablantes radioescuchas de Xepet (bilingües o monolingües en torno a la oferta cultural de la misma, así como a la presencia cotidiana de esta emisora en su mundo de vida; y, por otro, reflexionar acerca de la radio indigenista en México como un recurso que podría contribuir a la “cultura de paz”.“U chíikul u t’aan maayao’ob” o “La voz de los mayas”, salió al aire el 29 de noviembre de 1982, en la frecuencia de los 740 khz de AM y fue reubicada al 730 en enero de 2001. Su área de cobertura abarca unos 100 km a la redonda, alcanzando cerca de mil comunidades de la península y parte de Quintana Roo, con una audiencia potencial de 500 mil personas. Su programación incluye géneros musicales y no musicales, compuestos estos últimos por programas informativos, de difusión cultural, servicio e infantiles. Xepet ha sido una de las radiodifusoras pioneras del sistema indigenista promovido por el Estado mexicano desde 1979, modelo que habría de extenderse en las más de veinte emisoras que aparecieron después. Hoy en día, la crítica respecto de la función, contenidos y operación de estas emisoras “oficiales” o “voceras del Gobierno” permanence, debido a que tanto la práctica indigenista como su experiencia radiofónica parecieran estar rebasadas por las demandas de los pueblos indios que reivindican su derecho a la libre determinación y a la autonomía, así como a la propiedad y gestión de sus propios medios de comunicación. Lo anterior reitera la necesidad de una propuesta radiof

  6. Las organizaciones mayas de Guatemala y el diálogo intercultural

    OpenAIRE

    Julieta Carla Rostica

    2007-01-01

    Durante la transición a la democracia en Guatemala surgió un movimiento indígena con reivindicaciones que fueron más allá de la defensa de los derechos humanos individualmente considerados. De cara al genocidio, una de sus demandas más ambiciosas fue la del reconocimiento del derecho maya. El análisis de ésta permitirá caracterizar al movimiento indígena como multiculturalismo emancipatorio, ya que en sí misma es una apuesta al diálogo intercultural e implica no sólo un límite ...

  7. La langosta, los mayas y el colonialismo en Yucatán, México, 1883

    OpenAIRE

    García Quintanilla, Alejandra

    2012-01-01

    En 1883 se produjo una gran plaga de langosta que afectó a diversos estados de la República Mexicana. Tuvo su origen en Yucatán. Aquí se analizan las respuestas sociales de la sociedad civil integrada mayoritariamente por personas mayas, la de los hacendados henequeneros y también la del gobierno de Yucatán en lo que fue el inicio del llamado Auge Henequenero. In the year 1883, an enormous plague of locusts emerged in Yucatán and then spread out to raze several states in the Mexican Republ...

  8. PIXE analysis on Maya blue in Prehispanic and colonial mural paintings

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez del Rio, M. [Departamento de Fisica, Universidad Autonoma Metropolitana, Iztapalapa, DF 09340 (Mexico); Martinetto, P. [Laboratoire de Cristallographie, CNRS, BP 166, F-30842 Grenoble (France); Solis, C. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico, DF 04510 (Mexico)]. E-mail: corina@fisica.unam.mx; Reyes-Valerio, C. [Instituto Nacional de Antropologi' a e Historia, Mexico, DF (Mexico)

    2006-08-15

    Particle induced X-ray emission (PIXE) experiments have been carried out at the AGLAE facility (Paris) on several mural samples containing Maya blue from different Prehispanic archaeological sites (Cacaxtla, El Tajin, Tamuin, Santa Cecilia Acatitlan) and from several colonial convents in the Mexican plateau (Jiutepec, Totimehuacan, Tezontepec and Cuauhtinchan). The analysis of the concentration of several elements permitted to extract some information on the technique used for painting the mural, usually fresco. Principal component analysis permitted to classify the samples into groups. This grouping is discussed in relation to geographic and historic data.

  9. Las muchachas mayas de Yaxcabá, Yucatán

    Directory of Open Access Journals (Sweden)

    Maya Lorena Pérez Ruiz

    2017-01-01

    Full Text Available El tema de este artículo es el significado de ser mujer y ser joven en la cultura maya de Yucatán, México. Se presentan testimonios de muchachas de bachillerato del pueblo de Yaxcabá con el objetivo de conocer lo que para ellas significa ser mujer joven. Sus percepciones y sus proyectos de futuro se enmarcan en un campo de conflicto, en el que existe un enfrentamiento entre jóvenes y adultos para mantener o transformar los significados y las prácticas de ser joven.

  10. Las muchachas mayas de Yaxcabá, Yucatán

    OpenAIRE

    Maya Lorena Pérez Ruiz

    2017-01-01

    El tema de este artículo es el significado de ser mujer y ser joven en la cultura maya de Yucatán, México. Se presentan testimonios de muchachas de bachillerato del pueblo de Yaxcabá con el objetivo de conocer lo que para ellas significa ser mujer joven. Sus percepciones y sus proyectos de futuro se enmarcan en un campo de conflicto, en el que existe un enfrentamiento entre jóvenes y adultos para mantener o transformar los significados y las prácticas de ser joven.

  11. Measurement of the GMR in the Unstable 56Ni Nucleus using the Active Target Maya

    International Nuclear Information System (INIS)

    Monrozeau, C.; Khan, E.; Blumenfeld, Y.; Mittig, W.; Beaumel, D.; Caamano, M.; Cortina-Gil, D.; Demonchy, C.E.; Frascaria, N.; Garg, U.; Gelin, M.; Gillibert, A.; Gupta, D.; Marechal, F.; Obertelli, A.; Roussel-Chomaz, P.; Scarpaci, J.-A.

    2007-01-01

    The measurement of the Isoscalar Giant Monopole Resonance(GMR) in unstable nuclei remains a major experimental challenge due to low radioactive beam intensities and unfavourable conditions in reverse kinematics. At GANIL, we have tested a new experimental method based on the unique capabilities of the active target Maya to probe the GMR by the inelastic scattering reaction 56 Ni(d,d') at 50 AMeV. The preliminary excitation energy spectrum of 56 Ni presents a bump between 12 and 25 MeV where isoscalar resonances are expected

  12. Women’s Voices in a Male World: Actions, Bodies, and Spaces Among the Ancient Maya

    Directory of Open Access Journals (Sweden)

    Elisa Perego

    2007-11-01

    Full Text Available Feminist archaeology has prompted scholars to reconsider gender roles in ancient Mesoamerica.Current research, however, tends to focus on elite women, classes and sites. Although I do not ignore the potential of these sources, in this paper I am mainly concerned with issues such as the phenomenology of bodies and spaces, subroyal ritual actions, and daily activities such as cooking and weaving. My aim is to offer an overview of the most recent studies on gender in Maya archaeology and to provide ideas for further research by emphasising the need to engender ritual and individuate female discourses in the archaeological record.

  13. PIXE analysis on Maya blue in Prehispanic and colonial mural paintings

    Science.gov (United States)

    Sánchez del Río, M.; Martinetto, P.; Solís, C.; Reyes-Valerio, C.

    2006-08-01

    Particle induced X-ray emission (PIXE) experiments have been carried out at the AGLAE facility (Paris) on several mural samples containing Maya blue from different Prehispanic archaeological sites (Cacaxtla, El Tajín, Tamuin, Santa Cecilia Acatitlán) and from several colonial convents in the Mexican plateau (Jiutepec, Totimehuacán, Tezontepec and Cuauhtinchán). The analysis of the concentration of several elements permitted to extract some information on the technique used for painting the mural, usually fresco. Principal component analysis permitted to classify the samples into groups. This grouping is discussed in relation to geographic and historic data.

  14. Quality indicators and shelf life of red octopus (Octopus maya) in chilling storage

    OpenAIRE

    GULLIAN-KLANIAN,Mariel; SÁNCHEZ-SOLÍS,María José; TERRATS-PRECIAT,Montserrat; DELGADILLO-DÍAZ,Mariana; ARANDA,Javier

    2016-01-01

    Abstract There are no precedents concerning the quality of Octopus maya during chilled storage. This study evaluated the shelf life of the red octopus in chilling storage (4oC) and the correlation of the sensory quality index with microbiological counting and the biochemical indicators (hypoxanthine, histamine and volatile amines). A total of 112 whole raw octopi (average weight of 896 g) were randomly selected from seven batches and exposed to 4°C for 18, 24, 48, 72, 84, 96, and 100 h. The h...

  15. About the Glyph [T544.501] and the Classic Maya Geopolitical Communities

    Directory of Open Access Journals (Sweden)

    Rogelio Valencia Rivera

    2016-06-01

    Full Text Available This paper focuses on the Maya glyph [T544.501]. On one side the article offers a carefully review of the contexts where the hieroglyph appears for, from these, suggest that it may be a logogram with possible OCH ("entrance" reading. Moreover, considering the predominant appearance of this hieroglyph in contexts which relate to geopolitical groups, and beyond its phonetic value, the article also analyzes the historical dynamics that have experienced these Late Classic political groupings as narrate the texts where appears the glyph in question.

  16. Diagnostic utility of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) and its combination with the Addenbrooke's Cognitive Examination-Revised (ACE-R) in a memory clinic-based population.

    Science.gov (United States)

    Hancock, P; Larner, A J

    2009-06-01

    The study aimed to assess the clinical utility of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) in patients referred to memory clinics, alone and in combination with the Addenbrooke's Cognitive Examination-Revised (ACE-R) and the Mini-mental State Examination (MMSE). This pragmatic prospective study was based on consecutive referrals attending with an informant (n = 144) to two memory clinics over a 12-month period. Patients were diagnosed using standard clinical diagnostic criteria for dementia (DSM-IV) as gold standard (dementia prevalence = 59%). The IQCODE was administered to informants, and the ACE-R and/or MMSE to most patients. The IQCODE proved acceptable to informants, and was quick and easy to use. Using traditional parameters of diagnostic utility (sensitivity, specificity, positive predictive value, likelihood ratios), the performance of the IQCODE at optimal test accuracy was highly sensitive (0.86) for the diagnosis of dementia but specificity was poor (0.39) with suboptimal positive predictive value (0.67) and small or unimportant likelihood ratios. Overall diagnostic accuracy based on area under the receiver operating characteristic (ROC) curve was 0.71. Combining the IQCODE with either ACE-R or MMSE greatly improved accuracy, specificity and positive predictive value when the tests were used in series, but not when used in parallel. In a memory clinic based population, the IQCODE proved sensitive for the diagnosis of dementia but overall diagnostic accuracy was suboptimal. Combining the IQCODE in series with the ACE-R or MMSE greatly improved diagnostic utility.

  17. Sustaining Rainforest Plants, People and Global Health: A Model for Learning from Traditions in Holistic Health Promotion and Community Based Conservation as Implemented by Q’eqchi’ Maya Healers, Maya Mountains, Belize

    Directory of Open Access Journals (Sweden)

    Pablo Sanchez-Vindas

    2010-10-01

    Full Text Available The present work showcases a model for holistic, sustainable healthcare in indigenous communities worldwide through the implementation of traditional healing practices. The implementation of this model promotes public health and community wellness while addressing crucially important themes such as in situ and ex situ conservation of medicinal plant resources and associated biodiversity, generational transmission of knowledge, and the preservation of biological and cultural diversity for future generations. Being envisaged and implemented by Q’eqchi’ Maya traditional healers of the southern Maya Mountains, Belize, this model can be replicated in other communities worldwide. A ethnobotany study in collaboration with these healers led to collection of 102 medicinal species from Itzama, their traditional healing cultural center and medicinal garden. Of these 102 species, 40 of prior reported 106 consensus study plants were present in the garden. There were 62 plants not previously reported growing in the garden as well. A general comparison of these plants was also made in relation to species reported in TRAMIL network, Caribbean Herbal Pharmacopoeia (CHP, the largest regional medicinal pharmacopoeia. A relative few species reported here were found in the CHP. However, the majority of the CHP plants are common in Belize and many are used by the nearby Mopan and Yucatec Maya. Since these 102 species are relied upon heavily in local primary healthcare, this Q’eqchi’ Maya medicinal garden represents possibilities toward novel sustainable, culturally relative holistic health promotion and community based conservation practices.

  18. An Iterative Approach to Ground Penetrating Radar at the Maya Site of Pacbitun, Belize

    Directory of Open Access Journals (Sweden)

    Sheldon Skaggs

    2016-09-01

    Full Text Available Ground penetrating radar (GPR surveys provide distinct advantages for archaeological prospection in ancient, complex, urban Maya sites, particularly where dense foliage or modern debris may preclude other remote sensing or geophysical techniques. Unidirectional GPR surveys using a 500 MHz shielded antenna were performed at the Middle Preclassic Maya site of Pacbitun, Belize. The survey in 2012 identified numerous linear and circular anomalies between 1 m and 2 m deep. Based on these anomalies, one 1 m × 4 m unit and three smaller units were excavated in 2013. These test units revealed a curved plaster surface not previously found at Pacbitun. Post-excavation, GPR data were reprocessed to best match the true nature of excavated features. Additional GPR surveys oriented perpendicular to the original survey confirmed previously detected anomalies and identified new anomalies. The excavations provided information on the sediment layers in the survey area, which allowed better identification of weak radar reflections of the surfaces of a burnt, Middle Preclassic temple in the northern end of the survey area. Additional excavations of the area in 2014 and 2015 revealed it to be a large square structure, which was named El Quemado.

  19. Jugadores de pelota maya en tiempos del oxlajuj b’ak’tún

    Directory of Open Access Journals (Sweden)

    Jairzinho Francisco Panqueba Cifuentes

    2012-12-01

    Full Text Available La presente reflexión hace parte de un proceso investigativo cuyo objeto ha sido la práctica contemporánea del juego de pelota maya en Guatemala. Es un acercamiento analítico a los testimonios de vida recabados a través de la metodología de investigación-aprehendizaje compartida con los actores del proceso. Sus trayectorias vitales nos permiten comprender en descripciones y acciones, los detalles contemporáneos de una manifestación cultural, lúdica y recreativa ancestral. Pero también de qué maneras el juego de pelota mesoamericano es fuente de conocimientos de los patrimonios corporales hasta ahora difusos entre discursos relacionados con el folclor, las etnicidades, las artes, el deporte, la cultura, las espiritualidades y en general con ciencias como la historia, la antropología y la arqueología. Las vidas cotidianas de los actuales jugadores de pelota ayudan a comprender una parte de las sabidurías ancestrales mayas. Se integran, por tanto, a los testimonios de las herencias inmateriales arqueológicas representadas en los campos de juego de pelota diseminados por Mesoamérica.

  20. Role of water on formation and structural features of Maya blue

    International Nuclear Information System (INIS)

    Mondelli, C; Río, M Sánchez del; González, M A; Magazzú, A; Cavallari, C; Suárez, M; García-Romero, E; Romano, P

    2012-01-01

    The Maya blue (MB) is an artificial pigment created between 500-800 A.D. and used in murals, pottery and sculptures by Mayas and other people in Mesoamerica. MB is resistant to age, acid, weathering, biodegradation and even modern chemical solvents, but the chemical reasons behind the resistance to chemical aggressions are still under debate. Water plays a fundamental role in the interactions between indigo and clay. The dynamics of the clay's zeolitic and structural water molecules during the formation of MB, usually stabilized by moderate heating, has been monitored by means of neutron inelastic scattering. Neutron incoherent scattering in these samples is only due to the hydrogen atoms, so the signal is very sensitive to the amount of released water, providing detailed information on the dehydration process. A simultaneous analysis of the coherent elastic scattering and the incoherent scattering allows observing and quantifying how the structure of the clay is affected by dehydration. Here we show that a quite resistant pigment can be obtained at room temperature simply by dehydrating a palygorskite-indigo mixture employing only vacuum, without any thermal treatment.

  1. Synchrotron and Simulations Techniques Applied to Problems in Materials Science: Catalysts and Azul Maya Pigments

    International Nuclear Information System (INIS)

    Chianelli, R.

    2005-01-01

    Development of synchrotron techniques for the determination of the structure of disordered, amorphous and surface materials has exploded over the past twenty years due to the increasing availability of high flux synchrotron radiation and the continuing development of increasingly powerful synchrotron techniques. These techniques are available to materials scientists who are not necessarily synchrotron scientists through interaction with effective user communities that exist at synchrotrons such as the Stanford Synchrotron Radiation Laboratory (SSRL). In this article we review the application of multiple synchrotron characterization techniques to two classes of materials defined as ''surface compounds.'' One class of surface compounds are materials like MoS 2-x C x that are widely used petroleum catalysts used to improve the environmental properties of transportation fuels. These compounds may be viewed as ''sulfide supported carbides'' in their catalytically active states. The second class of ''surface compounds'' is the ''Maya Blue'' pigments that are based on technology created by the ancient Maya. These compounds are organic/inorganic ''surface complexes'' consisting of the dye indigo and palygorskite, a common clay. The identification of both surface compounds relies on the application of synchrotron techniques as described in this report

  2. Digestive Physiology of Octopus maya and O. mimus: Temporality of Digestion and Assimilation Processes

    Science.gov (United States)

    Gallardo, Pedro; Olivares, Alberto; Martínez-Yáñez, Rosario; Caamal-Monsreal, Claudia; Domingues, Pedro M.; Mascaró, Maite; Sánchez, Ariadna; Pascual, Cristina; Rosas, Carlos

    2017-01-01

    Digestive physiology is one of the bottlenecks of octopus aquaculture. Although, there are successful experimentally formulated feeds, knowledge of the digestive physiology of cephalopods is fragmented, and focused mainly on Octopus vulgaris. Considering that the digestive physiology could vary in tropical and sub-tropical species through temperature modulations of the digestive dynamics and nutritional requirements of different organisms, the present review was focused on the digestive physiology timing of Octopus maya and Octopus mimus, two promising aquaculture species living in tropical (22–30°C) and sub-tropical (15–24°C) ecosystems, respectively. We provide a detailed description of how soluble and complex nutrients are digested, absorbed, and assimilated in these species, describing the digestive process and providing insight into how the environment can modulate the digestion and final use of nutrients for these and presumably other octopus species. To date, research on these octopus species has demonstrated that soluble protein and other nutrients flow through the digestive tract to the digestive gland in a similar manner in both species. However, differences in the use of nutrients were noted: in O. mimus, lipids were mobilized faster than protein, while in O. maya, the inverse process was observed, suggesting that lipid mobilization in species that live in relatively colder environments occurs differently to those in tropical ecosystems. Those differences are related to the particular adaptations of animals to their habitat, and indicate that this knowledge is important when formulating feed for octopus species. PMID:28620313

  3. LA RELIGIOSIDAD MAYA- ACHI’ GUATEMALTECA COMO FUNDAMENTO DE SU IDENTIDAD CULTURAL

    Directory of Open Access Journals (Sweden)

    David Caballero Mariscal

    2017-12-01

    Full Text Available En el contexto general de Guatemala, caracterizado por la diversidad étnica y cultural, y mayoritariamente indígena, los achi’es constituyen menos de uno por ciento de la población. Sin embargo, y a pesar de que han sufrido la imposición cultural de pueblos vecinos, de los españoles, y posteriormente, un atroz genocidio, continúan conservando parte de su patrimonio cultural intangible, manifestado en la lengua, las danzas, el Rabinal achi’,y diversas sus expresiones religiosas, que, sin duda, se constituyen en el garante de su identidad cultural. El presente artículo pretende llenar el vacío existente actualmente sobre la etnia achi’, ante la ausencia de estudios sobre ésta. De igual modo, trata de profundizar sobre los mecanismos adaptativos de sincretismo que se han desarrollado a nivel cultural y religioso como medio de supervivencia a través de nuevos modos de transculturación, que garantizan la pervivencia de la cultura y religiosidad maya tradicional en el contexto de la fe católica, vigente y mayoritaria entre los miembros de este pueblo maya.

  4. Study of reactions induced by the halo nucleus 11Li with the active target MAYA

    International Nuclear Information System (INIS)

    Roger, Th.

    2009-09-01

    Active targets are perfect tools for the study of nuclear reactions induced by very low intensity radioactive ion beams. They also enable the simultaneous study of direct and compound nuclear reactions. The active target MAYA, built at GANIL, has been used to study the reactions induced by a 4.3*A MeV 11 Li beam at the ISAC2 accelerator TRIUMF (Canada). The angular distributions for the elastic scattering and the one and two neutron transfer reaction have been reconstructed. The elastic scattering angular distribution indicates a strong enhancement of the flux absorption with respect to the neighbouring nuclei. From a coupled channel analysis of the two neutron transfer reaction for different three body models, the information on the structure of the halo of the Borromean nucleus 11 Li have been extracted. Meanwhile, the energy dependence of the elastic scattering reaction has been studied, using the active target MAYA as a thick target. The resulting spectrum shows a resonance around 3 MeV centre of mass. This resonance could be an isobaric analog state of 12 Li, observed in 12 Be. R matrix calculations have been performed in order to extract the parameters (spin and parity) of this state. (author)

  5. Role of water on formation and structural features of Maya blue

    Science.gov (United States)

    Mondelli, C.; Sánchez del Río, M.; González, M. A.; Magazzú, A.; Cavallari, C.; Suárez, M.; García-Romero, E.; Romano, P.

    2012-02-01

    The Maya blue (MB) is an artificial pigment created between 500-800 A.D. and used in murals, pottery and sculptures by Mayas and other people in Mesoamerica. MB is resistant to age, acid, weathering, biodegradation and even modern chemical solvents, but the chemical reasons behind the resistance to chemical aggressions are still under debate. Water plays a fundamental role in the interactions between indigo and clay. The dynamics of the clay's zeolitic and structural water molecules during the formation of MB, usually stabilized by moderate heating, has been monitored by means of neutron inelastic scattering. Neutron incoherent scattering in these samples is only due to the hydrogen atoms, so the signal is very sensitive to the amount of released water, providing detailed information on the dehydration process. A simultaneous analysis of the coherent elastic scattering and the incoherent scattering allows observing and quantifying how the structure of the clay is affected by dehydration. Here we show that a quite resistant pigment can be obtained at room temperature simply by dehydrating a palygorskite-indigo mixture employing only vacuum, without any thermal treatment.

  6. Costa Oriental Maya: una acercamiento al comercio y navegación

    Directory of Open Access Journals (Sweden)

    Iván Renato Zúñiga Carrasco

    2014-01-01

    Full Text Available La costa oriental de la Península de Yucatán ofreció un medio ideal para navegantes y mercaderes por la geografía costera peninsular cruzada por extensas redes fluviales que se extienden a lo largo de sus costas y se remontan lejanamente en el interior. E l intercambio de productos a través de largas distancias fue un factor básico en la homogeneidad cultural del mundo maya, jugando un papel crítico en el desarrollo de esta antigua civilización. El comercio marítimo maya se remonta al periodo Preclásico Ta rdío (300 a.C. - 300 d.C. Muchos puertos estaban ubicados en lugares estratégicos para el comercio, como islas, promontorios o a la entrada de ríos y en la mayoría de las veces se ubicaban en lugares protegidos del mar abierto. Las canoas utilizadas por los nativos no se trataba de simples troncos ahuecados; el uso de velas además y remos como puede verse en representaciones en murales y códices.

  7. Nacionalismo maya y descolonización política: Luis de Lión y El tiempo principia en Xibalbá

    OpenAIRE

    del Valle Escalante, Emilio; University of North Carolina, Chapel Hill

    2015-01-01

    Este artículo analiza la novela El tiempo principia en Xibalbá (1985) del escritor maya kaqchikel Luis de Lión (1939-1984), considerada la primera novela escrita por un escritor maya en Guatemala. Leída como una de las primeras manifestaciones epistemológicas y políticas del llamado Movimiento Maya en Guatemala, la obra de Lión, como se argumenta en este trabajo, desmitifica y desarticula construcciones tradicionales y estereotipadas del mundo indígena en el discurso indigenista (la literatur...

  8. Population structure and group composition of western lowland gorillas in north-western Republic of Congo.

    Science.gov (United States)

    Magliocca, F; Querouil, S; Gautier-Hion, A

    1999-01-01

    Population studies are an essential part of conservation actions. Under exceptional observation conditions we studied a western lowland gorilla population visiting the Maya salt-clearing (north of the Parc national d'Odzala, P.N.O., Congo) over an 8 month period; 36 groups and 18 solitary individuals (a total of 420 individuals) have been identified visiting the clearing, which suggests a high gorilla density in the region. Ninety-six percent of the gorillas entered the clearing in groups. One-male groups had a mean size of 11.2. Ninety percent of solitary individuals were silver-back males. Compared with other populations of both lowland gorillas and mountain gorillas, the Maya population had the highest immature rate and the highest number of infants per female. Ecological correlates that could explain the attractiveness of the Maya clearing are discussed. The present status and the renewal rate of the Maya population indicate the need for further studies and confirm the importance of developing eco-tourism in this region as part of the sustainable park management activities developed by the ECOFAC programme (European Union). The results also provide arguments to support the proposal for extending the P.N.O. to include this region, which is rich in salt-clearings and attracts many other key-species of mammal such as forest elephants.

  9. Mathematical Contributions of the Mayas, Aztecs & Incas: A Native American Curriculum Unit for Middle and High School. NATAM XIX.

    Science.gov (United States)

    Stodola, Janet

    Written to fulfill the requirements for a University of Minnesota College of Education off-campus Indian education course for public school teachers, this Native American curriculum unit for middle and high school reflects the mathematical achievements of the Maya, Aztec, and Inca Indians. The number systems, notation, and calendar techniques of…

  10. 75 FR 6249 - Culturally Significant Objects Imported for Exhibition Determinations: “Fiery Pool: The Maya and...

    Science.gov (United States)

    2010-02-08

    ... exhibition ``Fiery Pool: The Maya and the Mythic Sea,'' imported from abroad for temporary exhibition within... objects at the Peabody Essex Museum, Salem, MA, from on or about March 27, 2010, until on or about July 18, 2010; the Kimbell Art Museum, Fort Worth, TX, from on or about August 29, 2010, until on or about...

  11. A comparative approach toward understanding the Mycenaean and Late Preclassic lowland Maya early civilisations through their art styles.

    NARCIS (Netherlands)

    Bajema, Marcus Jan

    2015-01-01

    My thesis provides a comparative analysis of early cilivilisations through archaeological sources. The two selected cases are Mycenaean Greece and the Late Preclassic lowland Maya. Specifically the study focuses on art and its role in social life of the two cases. Major methodological reflections

  12. Mangrove forest decline

    DEFF Research Database (Denmark)

    Malik, Abdul; Mertz, Ole; Fensholt, Rasmus

    2017-01-01

    Mangrove forests in the tropics and subtropics grow in saline sediments in coastal and estuarine environments. Preservation of mangrove forests is important for many reasons, including the prevention of coastal erosion and seawater intrusion; the provision of spawning, nursery, and feeding grounds...... of diverse marine biota; and for direct use (such as firewood, charcoal, and construction material)—all of which benefit the sustainability of local communities. However, for many mangrove areas of the world, unsustainable resource utilization and the profit orientation of communities have often led to rapid...... and severe mangrove loss with serious consequences. The mangrove forests of the Takalar District, South Sulawesi, are studied here as a case area that has suffered from degradation and declining spatial extent during recent decades. On the basis of a post-classification comparison of change detection from...

  13. Cultural or Ecological Sustainability? The Effect of Cultural Change on Sabal Palm Management Among the Lowland Maya of Mexico

    Directory of Open Access Journals (Sweden)

    Andrea Martínez-Ballesté

    2006-12-01

    Full Text Available Sabal palm has been used for thatching the traditional Maya house for over 3000 yr. The great importance of this resource has promoted its management within home gardens. Although traditionally managed populations in home gardens are capable of ecological long-term persistence, the impact of cultural change on sustainable resource management is poorly understood. By means of interviews in 108 households, we obtained information about Sabal management practices, leaf demand, and sociocultural data. Density and size structure of the palm populations in the respective home gardens were also measured. By means of principal components analysis, the sociocultural data were summarized into a cultural change index, which was then statistically related to palm density, size structure, leaf demand, and management practices. Leaf demand along the cultural change gradient was estimated. Sabal populations were affected by the cultural change index. Palm density and the proportion of harvestable individuals were higher in the more traditional households. The number of management practices decreased, and the probability of felling adult palms increased with cultural change. As a result, the percentage of the total leaf demand satisfied by home garden production diminished from 118.2-69.4% as cultural change increased. Traditional practices seem oriented to increasing the palm availability. Seed sowing and the protection of seedlings and adults affect the life stages with the largest impact on the population growth rate, as measured through sensitivity analysis. This means that abandoning traditional practices and felling adults more frequently should reduce rapidly, which is consistent with the low palm density observed in less traditional households. The application of demographic models to Sabal tells us that traditional management warrants the persistence of the resource as long as the current conditions remain unchanged. In contrast, our data show that

  14. Exploring the nexus between climate change, food security, and deforestation in Q'eqchi' Maya communities, Guatemala

    Science.gov (United States)

    Pope, I.; Harbor, J.

    2013-12-01

    The challenges of food security in the central Highlands of Guatemala are linked to deforestation, land degradation, and climate change. The Q'eqchi' Maya people that inhabit this region are smallholder farmers who rely on subsistence agriculture for survival. The Q'eqchi' support themselves with timber products and ecosystem services provided by the cloud forest, a unique ecosystem where a substantial portion of water is obtained through the condensation of water droplets onto vegetation via cloud filtration. Over the past 30 years, small-scale deforestation of the cloud forest in the Sierra Yalijux and Sacranix has increased as demand for agricultural land has risen. A link between the decline of cloud forest cover and an increase in severe precipitation events that drive soil erosion has been observed in the study area. As a result, land degradation poses a serious threat to the long-term food security of Q'eqchi' communities. We have examined the social, cultural, and land tenure dynamics that impact the ability of the Q'eqchi' to adapt to the rapidly changing climate, as well as to implement recommendations for grassroots initiatives to enhance these adaptations. Using remote-sensing we constructed three land use change maps that show that deforestation rates have increased by over 200% between 1986-2006 in the Sierra Yaljux and Sacranix mountain ranges, largely due to slash and burn agriculture. Using these land use change maps as an input into the Revised Universal Soil Loss Equation we show that implementation of agroecological techniques to counter the impacts of land use change drastically reduces soil erosion and is the best management practice. Surveys and focus groups in several Q'eqchi' villages revealed that precipitation events have become less frequent and more intense over the past 30 years, and temperatures have generally been increasing as well. Q'eqchi' people have observed that increasing severe precipitation events have accelerated soil

  15. Kinship and the decline of fertility.

    Science.gov (United States)

    Zhou, Y

    1996-01-01

    China's family planning and population control policies, together with the move toward a more market-oriented economy since the 1980s, have led to significant change in people's reproductive values and behavior and a substantial decline in fertility. Traditional kinship in China, its terminology, and the impact of fertility decline on kinship in China and Chinese society are discussed. The decline in fertility is affecting or will affect China's kinship system, the corresponding pattern of terminology, and the social structure. In the more market-oriented economy which has been developing in China, the simplification of the kinship system will help change the structure of Chinese society and weaken the traditional patriarchal culture. A more individualized, contractualized social structure and relationships will result.

  16. Gonad development during the early life of Octopus maya (Mollusca: Cephalopoda).

    Science.gov (United States)

    Avila-Poveda, Omar Hernando; Colin-Flores, Rafael Francisco; Rosas, Carlos

    2009-02-01

    Gonad development during the early life of Octopus maya is described in terms of histological, morphometric, oocytes growth, and somatic-oocyte relationship data obtained from octopus cultured at the UMDI-UNAM, in Sisal, Yucatan, Mexico. This study is the first publication on gonad development during the early life of Octopus maya. A total of 83 O. maya specimens were used; their sizes ranged from 6.5 to 76 mm of total length (TL), 4 to 28 mm of dorsal mantle length (DML), 2.5 to 20 mm of ventral mantle length (VML), and 0.0180 to 7.2940 g of fixed body weight (fBW). Animals were weighed and measured only after preservation. A loss of 10% of living weight was estimated for juvenile octopuses after formalin preservation. The relation of length to weight (VML, DML, TL/fBW) pooled for both sexes had a strong positive correlation (r), as shown by a potential power function that was quite close to 1. Compound images were produced from numerous microscopic fields. The histological examination revealed that, 4 months after hatching, male octopus (24.5 mm DML and 7.2940 g fBW) were in gonad stages 2 (maturing) to 3 (mature), with spermatogonia and spermatocytes in the tubule wall and abundant spermatids and spermatozoa in the central lumen of the seminiferous tubules, suggesting the occurrence of different phases of gonad development at different maturity stages. In contrast, females (22.5 mm DML and 4.8210 g fBW) at the same time since hatching were immature (stage 1), with many oogonia, few oocytes, and germinal epithelium. This suggests that males reach maturity earlier than females, indicating a probable onset of maturity for males at around 4 months of culture or 8 g of wet body weight. Our results indicate the possibility that the size-at-weight can be recognized early with a degree of certainty that allows the sexes to be separated for culture purposes; but more detailed studies on reproduction in relation to endocrinology and nutrition are needed.

  17. The Movement, the Mine and the Lake: New Forms of Maya Activism in Neoliberal Guatemala

    Directory of Open Access Journals (Sweden)

    J. T. Way

    2016-07-01

    Full Text Available This article explores the social, economic, cultural and political issues bound up in two matters relating to the environment in the Sololá and Lake Atitlán region of the Guatemalan Mayan highlands in 2004–2005: the violent breakup of an anti-mine protest and the various reactions to a tropical storm that threatened the lake ecosystem. It views these events as part of a historical conjuncture and centers them in a larger discussion of Maya political activism, environmentalism and neoliberal development in Guatemala from the 1990s–mid-2010s. It begins with the transition from war to peace in the 1990s, charting how Maya participation in municipal politics soared even as the official Mayan movement waned as the state turned to neoliberalism. Zooming in on municipal development and politics in Sololá in the early 2000s, it then traces at the ground level how a decentralizing, “multicultural” state promoted political participation while at the same time undermining the possibility for that participation to bring about substantive change. The center of the article delves deeper into the conjuncture of the first decade of the new millennium. By mapping events in Sololá against development, agrarian transformation and rural urbanization, it argues that resilient Maya community structures, although unable to stop the exploitative tide, continued to provide local cohesion and advocacy. Activists and everyday citizens became more globally attuned in the 2000s. The article’s final section analyzes municipal plans made between 2007 and 2012, arguing that creating and controlling community structures became increasingly important to the state in a time when Guatemala’s “outward” global turn was accompanied by an “inward” turn as people confronted spiraling violence in their communities. Critics called young people apolitical, but in 2015, massive demonstrations led to the imprisonment of the nation’s president and vice

  18. Declining world fertility: trends, causes, implications.

    Science.gov (United States)

    Tsui, A O; Bogue, D J

    1978-10-01

    This Bulletin examines the evidence that the world's fertility has declined in recent years, the factors that appear to have accounted for the decline, and the implications for fertility and population growth rates to the end of the century. On the basis of a compilation of estimates available for all nations of the world, the authors derive estimates which indicate that the world's total fertility rate dropped from 4.6 to 4.1 births per woman between 1968 and 1975, thanks largely to an earlier and more rapid and universal decline in the fertility of less developed countries (LDCs) than had been anticipated. Statistical analysis of available data suggests that the socioeconomic progress made by LDCs in this period was not great enough to account for more than a proportion of the fertility decline and that organized family planning programs were a major contributing factor. The authors' projections, which are compared to similar projections from the World Bank, the United Nations, and the U.S. Bureau of the Census, indicate that, by the year 2000, less than 1/5 of the world's population will be in the "red danger" circle of explosive population growth (2.1% or more annually); most LDCs will be in a phase of fertility decline; and many of them -- along with most now developed countries -- will be at or near replacement level of fertility. The authors warn that "our optimistic prediction is premised upon a big IF -- if (organized) family planning (in LDCs) continues. It remains imperative that all of the developed nations of the world continue their contribution to this program undiminished."

  19. Alarming decline and range reduction of the highly threatened Great ...

    African Journals Online (AJOL)

    A Great Bustard Otis tarda survey carried out in spring 2015 in Morocco confirmed the decline of this highly endangered population. Bustards were only seen at two of the seven leks occupied ten years ago. The total number of birds counted was 40-44, which represents a 40% decline over the last decade. The sex-ratio ...

  20. Does Child Labor Decline with Improving Economic Status?

    Science.gov (United States)

    Edmonds, Eric V.

    2005-01-01

    The rapid economic growth of Vietnam provides an interesting insight into the sharp decline in child labor. A study of the rising economic status of the population across Vietnam shows that children returned to school or stopped working as their family incomes grew. The decline in child labor is steep in poor households as they emerged from…

  1. A mask for high-intensity heavy-ion beams in the MAYA active target

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez-Tajes, C., E-mail: rodriguez@ganil.fr [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen (France); Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Pancin, J.; Damoy, S.; Roger, T.; Babo, M. [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen (France); Caamaño, M. [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Farget, F.; Grinyer, G.F.; Jacquot, B.; Pérez-Loureiro, D. [Grand Accélérateur National d' Ions Lourds (GANIL), CEA/DSM-CNRS/IN2P3, Bvd Henri Becquerel, 14076 Caen (France); Ramos, D. [Universidade de Santiago de Compostela, E-15706 Santiago de Compostela (Spain); Suzuki, D. [Institut de Physique Nucléaire, Université Paris-Sud 11, CNRS/IN2P3, F-91406 Orsay (France)

    2014-12-21

    The use of high-intensity and/or heavy-ion beams in active targets and time-projection chambers is often limited by the strong ionization produced by the beam. Besides the difficulties associated with the saturation of the detector and electronics, beam-related signals may hide the physical events of interest or reduce the detector performance. In addition, space-charge effects may deteriorate the homogeneity of the electric drift field and distort the subsequent reconstruction of particle trajectories. In anticipation of future projects involving such conditions, a dedicated beam mask has been developed and tested in the MAYA active target. Experimental results with a {sup 136}Xe beam are presented.

  2. Coca-colonization and hybridization of diets among the Tz'utujil Maya.

    Science.gov (United States)

    Nagata, Jason M; Barg, Frances K; Valeggia, Claudia R; Bream, Kent D W

    2011-01-01

    Biomedical health professionals express increasing concern that rising consumption of soft drinks and processed foods in Mayan and Latin American eating patterns may lead to detrimental nutritional and health consequences. Scholars debate whether the pervading presence of Coca-Cola and Pepsi in developing countries represents "Coca-Colonization," synonymous with cultural imperialism, or cultural hybridization. Using mixed qualitative and quantitative research methods, including participant observation and semi-structured interviews, this study explores the development of Coca-Colonization and cultural hybridization among the Tz'utujil Maya of Santiago Atitlán, Guatemala. By specifically examining biomedical perspectives, cycles of conquest, the political economy, religion, celebrations, and the physical environment through the lens of soft drinks, this study finds that Coca-Colonization and cultural hybridization are complementary rather than mutually exclusive processes that contribute to dietary transitions, economic development, and differential health beliefs related to soft drink consumption.

  3. La noción del tiempo en la cultura maya prehispánica

    Directory of Open Access Journals (Sweden)

    Alexander Wolfgang Voss

    2015-07-01

    Full Text Available La concepción del tiempo de los mayas prehispánicos se estudia mediante el análisis epigráfico y filológico de textos jeroglíficos bajo los planteamientos teóricos de la escuela italiana de historia de las religiones. Los datos indican que el tiempo es animado y formado por unidades discretas tangibles que se representan con un calendario de 365 días. Las características de cada día son fijadas por un oráculo de suertes de 260 unidades que es proyectado sobre el tiempo. El tiempo y el oráculo son pensados como dioses que se alternan en un orden y no como una magnitud física abstracta.

  4. ¡Si acatamos la onstitución, resistiremos!: Mayas Yucatecos durante la Independencia

    Directory of Open Access Journals (Sweden)

    Izaskun ALVAREZ CUARTERO

    2011-04-01

    Full Text Available El presente artículo analiza la etapa independentista desde la óptica de los actores silenciados, el grupo indígena mayoritario en la península, los mayas yucatecos, que observan el paso de ser súbditos a ciudadanos acatando la Constitución, solicitando que se cumplan las prerrogativas que se les concedieron y participando cívicamente en la creación de los ayuntamientos. Este cambio de actitud, posibilitado por la legitimidad que les otorgaban las Cortes de Cádiz, dio a los grupos subalternos la misma capacidad de representación que a los sectores dominantes. Estudiaremos hasta qué punto acatar el nuevo orden constitucional fue un acto de resistencia, una etapa más de sometimiento que terminaría estallando en 1847 en la Guerra de Castas.

  5. El discurso de los mayas yucatecos frente a los colonizadores: limosnas y secularización

    Directory of Open Access Journals (Sweden)

    Pedro Bracamonte y Sosa

    2015-06-01

    Full Text Available Este artículo recoge un aspecto de la intrincada relación entre franciscanos y mayas en la época colonial. Está sustentado en documentos y en la experiencia del autor en el estudio del Yucatán de los siglos XVI-XVIII. Si en esta provincia los frailes franciscanos lograron defenderse durante largo tiempo de la secularización de sus conventos y doctrinas fue precisamente porque lograron mantener a su favor la buena voluntad de las élites indígenas, a pesar de los conflictos locales que sucedían en forma intermitente. Para los caciques y chuntanes o principales, era evidente que sin su decidida participación la orden de San Francisco poco podía hacer para enfrentar la creciente fuerza del obispado de donde emanaban las líneas generales de la vida religiosa de toda la provincia.

  6. The Poetics of the Ancestor Songs of the Tz’utujil Maya of Guatemala

    Directory of Open Access Journals (Sweden)

    Linda O’Brien-Rothe

    2010-04-01

    Full Text Available This essay attempts to define the relationship between a song tradition that survives in the Mayan highlands of Guatemala, and 16th century poetic Mayan literature. This song tradition of Santiago Atitlán, Guatemala is slowly disappearing as the socio-cultural context in which it flourished changes. By comparing the poetics of the song texts (including their rhythmic structure, versification, and use of poetic devices such as assonance, alliteration and onomatopoeia to the poetics of the Popol Vuh, a K’iché Maya text probably copied from a manuscript that predates the Spanish invasion, a continuity is discovered that places the song texts squarely within the tradition of Mayan literature and suggests common origins.

  7. Organización territorial de los antiguos mayas de Belice Central

    DEFF Research Database (Denmark)

    Helmke, Christophe; Awe, Jaime

    2008-01-01

    Los modelos propuestos para la organización territorial de los mayas del período clásico en Belice Central difieren significativamente de un investigador a otro. Debido a la escasez de datos jeroglíficos, la mayoría de los modelos se han formulado teniendo en cuenta tan solo datos arqueológicos y...... se centran predominantemente sobre cada sitio investigado. Las exploraciones en Belice Central de las cuatro últimas décadas, sin embargo, han sacado a la luz numerosas piezas clave que aportan datos epigráficos, incluyendo “Glifos Emblema”. Vistos en conjunto, los datos arqueológicos y epigráficos...... proporcionan una posición más ventajosa en la determinación de la estructura del paisaje socio-político del Período Clásico del Valle de Belice. Udgivelsesdato: 2008...

  8. Milpa y capitalismo: opciones para los campesinos mayas yucatecos contemporáneos

    Directory of Open Access Journals (Sweden)

    Manuel Martín Castillo

    2016-07-01

    Full Text Available La mayoría de los mayas yucatecos contemporáneos vive en la pobreza. El eje de su economía y cultura es la agricultura de milpa, que los jóvenes no encuentran atractiva como opción económica. La teoría económica convencional explica la pobreza por la escasez de capital, el uso de tecnologías obsoletas y la baja productividad. Aunque se concibe como un sistema productivo arcaico, la milpa tiene características para explorar opciones de vinculación entre las economías campesina y capitalista, para mejorar las condiciones de vida de los campesinos y contribuir al desarrollo de su cultura en el actual contexto de globalización económica.

  9. Human Migration and Agricultural Expansion: An Impending Threat to the Maya Biosphere Reserve

    Science.gov (United States)

    Sader, Steven; Reining, Conard; Sever, Thomas L.; Soza, Carlos

    1997-01-01

    Evidence is presented of the current threats to the Maya Biosphere Reserve in northern Guatemala as derived through time-series Landsat Thematic Mapper observations and analysis. Estimates of deforestation rates and trends are examined for different management units within the reserve and buffer zones. The satellite imagery was used to quantify and monitor rates, patterns, and trends of forest clearing during a time period corresponding to new road construction and significant human migration into the newly accessible forest region. Satellite imagery is appropriate technology in a vast and remote tropical region where aerial photography and extensive field-based methods are not cost-effective and current, timely data is essential for establishing conservation priorities.

  10. The Source of Volcanic Ash in Late Classic Maya Pottery at El Pilar, Belize

    Science.gov (United States)

    Catlin, B. L.; Ford, A.; Spera, F. J.

    2007-12-01

    The presence of volcanic ash used as temper in Late Classic Maya pottery (AD 600-900) at El Pilar has been long known although the volcano(s) contributing ash have not been identified. We use geochemical fingerprinting, comparing compositions of glass shards in potsherds with volcanic sources to identify the source(s). El Pilar is located in the Maya carbonate lowlands distant from volcanic sources. It is unlikely Maya transported ash from distant sites: ash volumes are too large, the terrain too rugged, and no draft animals were available. Ash layer mining is unlikely because mine sites have not been found despite intensive surveys. Nearest volcanic sources to El Pilar, Belize and Guatemala, are roughly 450 km to the south and east. The ash found in potsherds has a cuspate morphology. This suggests ash was collected during, or shortly after, an ash airfall event following eruption. Analyses of n=333 ash shards from 20 ceramic (pottery) sherds was conducted by electron microprobe for major elements, and LA-ICPMS for trace elements and Pb isotopes. These analyses can be compared to volcanic materials from candidate volcanoes in the region. The 1982 El Chichon eruption caused airfall deposition (archaeological samples and El Chichon has been made. The atomic ratios of La/Yb, Nb/Ta, Zr/Hf, Sr/Ba and Th/U of n=215 glass shards in the potsherds are 12.2±7.1, 10.9±3.4, 31.2±11.5, 0.09±0.05 and 2.5±0.9, respectively. These ratios for 1982 El Chichon are 15.4±2.1, 26.3, 36.1±5.3, 1.4±0.06 and 3.16, respectively. Data for the 1475 AD El Chichon eruption (Macias et al, 2003) can also be compared; the ratios from are 13.2±2.2, 7.3±1.8, 30.4±9.6, 1.51±0.4 and 2.88±0.23, respectively. The mean 208Pb/206Pb ratio of n=5 potsherds is 2.0523±0.002 compared to 2.0514±0.00074 for n=7 samples from El Chichon. The two most recent eruptions from El Chichon overlap with the potsherd glass data except for Sr/Ba, which might be modified by Sr-Ca exchange during firing. In

  11. Chemometric study of Maya Blue from the voltammetry of microparticles approach.

    Science.gov (United States)

    Doménech, Antonio; Doménech-Carbó, María Teresa; de Agredos Pascual, María Luisa Vazquez

    2007-04-01

    The use of the voltammetry of microparticles at paraffin-impregnated graphite electrodes allows for the characterization of different types of Maya Blue (MB) used in wall paintings from different archaeological sites of Campeche and YucatAn (Mexico). Using voltammetric signals for electron-transfer processes involving palygorskite-associated indigo and quinone functionalities generated by scratching the graphite surface, voltammograms provide information on the composition and texture of MB samples. Application of hierarchical cluster analysis and other chemometric methods allows us to characterize samples from different archaeological sites and to distinguish between samples proceeding from different chronological periods. Comparison between microscopic, spectroscopic, and electrochemical examination of genuine MB samples and synthetic specimens indicated that the preparation procedure of the pigment evolved in time via successive steps anticipating modern synthetic procedures, namely, hybrid organic-inorganic synthesis, temperature control of chemical reactivity, and template-like synthesis.

  12. A method for generating stochastic 3D tree models with Python in Autodesk Maya

    Directory of Open Access Journals (Sweden)

    Nemanja Stojanović

    2016-12-01

    Full Text Available This paper introduces a method for generating 3D tree models using stochastic L-systems with stochastic parameters and Perlin noise. L-system is the most popular method for plant modeling and Perlin noise is extensively used for generating high detailed textures. Our approach is probabilistic. L-systems with a random choice of parameters can represent observed objects quite well and they are used for modeling and generating realistic plants. Textures and normal maps are generated with combinations of Perlin noises what make these trees completely unique. Script for generating these trees, textures and normal maps is written with Python/PyMEL/NumPy in Autodesk Maya.

  13. José Martí, Viajes y Apreciación del Pueblo Maya

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Bojórquez Urzaiz

    2015-09-01

    Full Text Available Este trabajo expone y examina los cambios de percepción que experimentó José Martí sobre el papel de los pueblos originarios de América, entre 1875 y 1878, años en los que vivió en México y Guatemala, con intensa escala en Yucatán, lugares donde conoció directamente la cultura y el pueblo maya. Martí resume una visión inicial de nuestra América en la figura lítica de Chacmool cuando después de ser expropiada por el gobierno yucateco, el Apóstol cubano la admira en la ciudad de Mérida y expresa que es la síntesis de las culturas americanas. Aspecto poco estudiado en la obra de Martí es este acercamiento etnográfico a la realidad maya de Yucatán y Guatemala.   This paper aims at presenting and examining the change of perception José Martí underwent in relation to the role of the native peoples of America between 1875 and 1878, the years he lived in Mexico and Guatemala, during which he spent a large amount of time in Yucatan, where he was able to get to know the Mayan culture and its people first hand. Martí summarized his initial vision of our America in the lithic figure of Chacmool, which he was able to admire in the city of Merida, after it had been expropriated by the government of Yucatan. The Cuban apostle described this as a synthesis of American cultures. This ethnographic insight into the Mayan reality in Yucatan and Guatemala represents a scarcely explored aspect of Martí's work.

  14. Paleomagnetism of the Todos Santos Formation in the Maya Block, Chiapas, Mexico: Preliminary Results

    Science.gov (United States)

    Godinez-Urban, A.; Molina-Garza, R. S.; Iriondo, A.; Geissman, J. W.

    2008-12-01

    Preliminary results of a paleomagnetic study on jurassic volcanic rocks (U-Pb 188.8 +/- 3.2Ma) locally interbedded with red beds assigned to the Todos Santos Formation, sampled in the Homoclinal Tectonic Province of the Neogene Fold Belt, Chiapas-Mexico, reveal multi component magnetizations acquired during pre- and post- folding of these rocks. The samples responded well to thermal demagnetization, but not so to AF demagnetization, suggesting that a high coercivity mineral phase like hematite is the main remanence carrier. The post-folding B-component direction of Dec=174.3 Inc=-30.6 (k=46; alpha95=13.6; N=4) represents a recent Tertiary? overprint; while the pre-folding C-component direction of Dec=329.9 Inc=7.8 (k=12.5; alpha95=16.3; N=8) is in agreement with a previously reported small data set for the Todos Santos Formation. When compared to the North American reference direction (Jurassic Kayenta Formation) the observed direction indicates a counterclockwise rotation of 35.9 +/- 16.6 degrees, and moderate north to south latitudinal displacement. If a reference pole from NE North America is used, the amount of counterclockwise rotation and latitudinal displacement are both slightly reduced. If the assumption that Jurassic strata in Chiapas reflect displacement of the Maya Block, then these data are consistent with reconstructions of the Maya Block in the Gulf of Mexico region. Other sites sampled in Jurassic strata suggest that in addition to the interpreted regional rotation, local (vertical-axis) rotations may have affected the region in more recent times.

  15. Near-surface Imaging of a Maya Plaza Complex using Ground-Penetrating Radar

    Science.gov (United States)

    Aitken, J. A.; Stewart, R. R.

    2005-05-01

    The University of Calgary has conducted a number of ground-penetrating radar surveys at a Maya archaeological site. The purpose of the study is to discern the near-surface structure and stratigraphy of the plaza, and to assist the archaeologists in focusing their excavation efforts. The area of study is located in Belize, Central America at the ancient Maya site of Maax Na. Flanked by structures believed to be temples to the north and west, the archaeologists were interested in determining how many levels of plaza were built and if there was any discernable slope to the plaza. Over the last three years, both 2-D lines and 3-D grids were acquired at the plaza using a Sensors and Software Inc. Noggin Plus system at an antenna frequency of 250 MHz. The processing flow consisted of the application of gain, various filtering techniques and a diffraction stack migration using Reflexw. Interpolation of the gridded data was investigated using simple averaging, F-K migration, pre-stack migration and inversion techniques. As this study has evolved over different field seasons, measured velocities appear to change with the saturation level of the shallow section. Velocity measurements ranged from 0.058 - .106 m/ns during the wet conditions encountered in 2002 and 2004, while velocities of 1.22 - 1.40 m/ns were measured in the drought of 2003. The GPR images to date indicate continuous and interpretable images of the subsurface, showing evidence of structure, discontinuities and amplitude variations. A number of interesting anomalies have been identified, and prioritized for excavation.

  16. Cessation of a salmon decline with control of parasites

    KAUST Repository

    Peacock, Stephanie J.; Krkošek, Martin; Proboszcz, Stan; Orr, Craig; Lewis, Mark A.

    2013-01-01

    (Oncorhynchus gorbuscha) from Pacific Canada indicates that adaptive changes in parasite management on salmon farms have yielded positive conservation outcomes. After four years of sea lice epizootics and wild salmon population decline, parasiticide application

  17. Neighborhood Decline and the Economic Crisis (discussion paper)

    NARCIS (Netherlands)

    Zwiers, M.D.; Bolt, G.; Van Ham, M.; Van Kempen, R.

    2014-01-01

    Neighborhood decline is a complex and multidimensional process. National and regional variation in economic and political structures (including variety in national welfare state arrangements), combined with differences in neighborhood history, development and population composition, makes it

  18. Poison blamed for decline of Spain's majestic Black Vultures

    African Journals Online (AJOL)

    2007-03-01

    catastrophic” decline in numbers because of illegal poisoning by hunters. The use of poisoned bait to kill foxes, badgers, wild dogs, feral cats and smaller birds of prey has reduced the population by almost a half in the past decade,.

  19. Farmer's lung is now in decline.

    LENUS (Irish Health Repository)

    Arya, A

    2012-02-03

    Farmer\\'s lung incidence in Ireland was constant until 1996, even though hay making methods were revolutionised in late 1980\\'s. We undertook this study to find out the incidence of farmer\\'s lung in Ireland from 1982-2002 and its correlation with rainfall and the effect of changing farm practices. The primary cases of farmer\\'s lung were identified from Hospital in Patients Enquiry (HIPE) unit of the national Economic & Social Research Institute (ESRI) Dublin. Rainfall data were obtained from Met Eireann whereas population, hay production and silage production were obtained from the Central Statistics Office, Dublin. As the farming population is in decline, we used the annual working unit (AWU), which reflects the true population at risk. An AWU is the equivalent of 1800 hours per farm worker per year. The incidence rates were constant from 1982-1996, but from 1997-2002 a marked decline was observed. There was strong positive correlation with hay production (r = 0.81) and strong negative correlation with silage production (r = -0.82). This study indicates that the incidence of farmer\\'s lung is now in decline.

  20. IQ as moderator of terminal decline in perceptual and motor speed, spatial, and verbal ability: Testing the cognitive reserve hypothesis in a population-based sample followed from age 70 until death.

    Science.gov (United States)

    Thorvaldsson, Valgeir; Skoog, Ingmar; Johansson, Boo

    2017-03-01

    Terminal decline (TD) refers to acceleration in within-person cognitive decline prior to death. The cognitive reserve hypothesis postulates that individuals with higher IQ are able to better tolerate age-related increase in brain pathologies. On average, they will exhibit a later onset of TD, but once they start to decline, their trajectory is steeper relative to those with lower IQ. We tested these predictions using data from initially nondemented individuals (n = 179) in the H70-study repeatedly measured at ages 70, 75, 79, 81, 85, 88, 90, 92, 95, 97, 99, and 100, or until death, on cognitive tests of perceptual-and-motor-speed and spatial and verbal ability. We quantified IQ using the Raven's Coloured Progressive Matrices (RCPM) test administrated at age 70. We fitted random change point TD models to the data, within a Bayesian framework, conditioned on IQ, age of death, education, and sex. In line with predictions, we found that 1 additional standard deviation on the IQ scale was associated with a delay in onset of TD by 1.87 (95% highest density interval [HDI; 0.20, 4.08]) years on speed, 1.96 (95% HDI [0.15, 3.54]) years on verbal ability, but only 0.88 (95% HDI [-0.93, 3.49]) year on spatial ability. Higher IQ was associated with steeper rate of decline within the TD phase on measures of speed and verbal ability, whereas results on spatial ability were nonconclusive. Our findings provide partial support for the cognitive reserve hypothesis and demonstrate that IQ can be a significant moderator of cognitive change trajectories in old age. (PsycINFO Database Record (c) 2017 APA, all rights reserved).