WorldWideScience

Sample records for high continental endemism

  1. Inferring the biogeographic origins of inter-continental disjunct endemics using a Bayes-DIVA approach

    Institute of Scientific and Technical Information of China (English)

    AJ HARRIS; Jun WEN; Qiu-Yun (Jenny) XIANG

    2013-01-01

    The arcto-Tertiary relictual flora is comprised of many genera that occur non-contiguously in the temperate zones of eastern Asia,Europe,eastern North America,and westem North America.Within each distributional area,species are typically endemic and may thus be widely separated from closely related species within the other areas.It is widely accepted that this common pattern of distribution resulted from of the fragmentation of a once morecontinuous arcto-Tertiary forest.The historical biogeographic events leading to the present-day disjunction have often been investigated using a phylogenetic approach.Limitations to these previous studies have included phylogenetic uncertainty and uncertainty in ancestral range reconstructions.However,the recently described Bayes-DIVA method handles both types of uncertainty.Thus,we used Bayes-DIVA analysis to reconstruct the stem lineage distributions for 185 endemic lineages from 23 disjunct genera representing 17 vascular plant families.In particular,we asked whether endemic lineages within each of the four distributional areas more often evolved from (1) widespread ancestors,(2) ancestors dispersed from other areas,or (3) endemic ancestors.We also considered which of these three biogeographic mechanisms may best explain the origins of arcto-Tertiary disjunct endemics in the neotropics.Our results show that eastern Asian endemics more often evolved from endemic ancestors compared to endemics in Europe and eastern and western North America.Present-day endemic lineages in the latter areas more often arose from widespread ancestors.Our results also provide anecdotal evidence for the importance of dispersal in the biogeographic origins of arcto-Tertiary species endemic in the neotropics.

  2. Universal species-area and endemics-area relationships at continental scales.

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    Storch, David; Keil, Petr; Jetz, Walter

    2012-08-02

    Despite the broad conceptual and applied relevance of how the number of species or endemics changes with area (the species-area and endemics-area relationships (SAR and EAR)), our understanding of universality and pervasiveness of these patterns across taxa and regions has remained limited. The SAR has traditionally been approximated by a power law, but recent theories predict a triphasic SAR in logarithmic space, characterized by steeper increases in species richness at both small and large spatial scales. Here we uncover such universally upward accelerating SARs for amphibians, birds and mammals across the world’s major landmasses. Although apparently taxon-specific and continent-specific, all curves collapse into one universal function after the area is rescaled by using the mean range sizes of taxa within continents. In addition, all EARs approximately follow a power law with a slope close to 1, indicating that for most spatial scales there is roughly proportional species extinction with area loss. These patterns can be predicted by a simulation model based on the random placement of contiguous ranges within a domain. The universality of SARs and EARs after rescaling implies that both total and endemic species richness within an area, and also their rate of change with area, can be estimated by using only the knowledge of mean geographic range size in the region and mean species richness at one spatial scale.

  3. Southern Tunisia: A still high endemicity area for hepatitis A.

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    Neffatti, Houcine; Lebraud, Patricia; Hottelet, Corinne; Gharbi, Jawher; Challouf, Taieb; Roque-Afonso, Anne-Marie

    2017-01-01

    Hepatitis A (HAV) and E (HEV) viruses are responsible for enterically transmitted hepatitis. Tunisia is reported to be of intermediate endemicity for HAV and of low seroprevalence for HEV; however, data from rural areas of South Tunisia are lacking. Sera from 216 asymptomatic pregnant women and from 92 patients with acute hepatitis were collected between October 2014 and November 2015. Total and IgM anti-HAV immunoglobulins and anti-HEV IgG and IgM were investigated. Anti-HAV IgM-positive samples were subjected to RT-PCR targeting the VP1/2A region and sequenced. HEV IgM positive samples and all samples from acute hepatitis patients were assessed for HEV RNA. Among pregnant women (mean age 32+/-8), HAV seroprevalence was 98.6%, none presented anti-HAV IgM; HEV seroprevalence was 5.1% and three presented weakly reactive anti-HEV IgM without detectable RNA. Among acute hepatitis patients (mean age 18.5 +/- 14), HEV seroprevalence was 19,5%, none presented anti-HEV IgM, nor HEV RNA. HAV seroprevalence exceeded 90% by age 5 and acute HAV infection was detected in 20 patients (21,7%), younger than patients with other hepatitis causes (9,8 years vs. 20,4 years, p = 0,004); 65% were male. Most acute HAV infections were observed in a coastal area where HAV infections represented 52% of hepatitis etiology. Phylogenetic analysis identified genotype IA strains, clustering close to previously published Tunisian sequences. The present study confirmed a low HEV endemicity and evidenced a still high level of HAV circulation in Southern Tunisia, suggesting distinct dissemination patterns for these viruses.

  4. Plasmodium falciparum transmission blocking immunity under conditions of low and high endemicity in Cameroon.

    NARCIS (Netherlands)

    Boudin, C.; Kolk, M. van der; Tchuinkam, T.; Gouagna, C.; Bonnet, S.; Safeukui, I.; Mulder, B.J.M.; Meunier, J.Y.; Verhave, J.P.

    2004-01-01

    Transmission blocking immunity (TBI) was studied in relation to age, gametocyte density and transmission intensity. subjects with high gametocytaemias were selected in a hypo-endemic urban district and a hyper-endemic rural area in South Cameroon. TBI was determined in blood from gametocyte carriers

  5. High unexpected genetic diversity of a narrow endemic terrestrial mollusc.

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    Madeira, Pedro M; Chefaoui, Rosa M; Cunha, Regina L; Moreira, Francisco; Dias, Susana; Calado, Gonçalo; Castilho, Rita

    2017-01-01

    The Iberian Peninsula has an extensive record of species displaying strong genetic structure as a result of their survival in isolated pockets throughout the Pleistocene ice ages. We used mitochondrial and nuclear sequence data to analyze phylogeographic patterns in endemic land snails from a valley of central Portugal (Vale da Couda), putatively assigned to Candidula coudensis, that show an exceptionally narrow distributional range. The genetic survey presented here shows the existence of five main mitochondrial lineages in Vale da Couda that do not cluster together suggesting independent evolutionary histories. Our results also indicate a departure from the expectation that species with restricted distributions have low genetic variability. The putative past and contemporary models of geographic distribution of Vale da Couda lineages are compatible with a scenario of species co-existence in more southern locations during the last glacial maximum (LGM) followed by a post-LGM northern dispersal tracking the species optimal thermal, humidity and soil physical conditions.

  6. Can migrants from high-endemic countries cause new HIV outbreaks among heterosexuals in low-endemic countries?

    NARCIS (Netherlands)

    M. Xiridou; M. van der Veen; R. Coutinho; M. Prins

    2010-01-01

    Objectives: To investigate how the sexual behaviour of migrants originating from HIV-endemic countries affects the spread of HIV among heterosexuals in low-endemic countries. Methods: A mathematical model is developed describing the transmission of HIV in heterosexual partnerships between African mi

  7. The Northern Bolivian Altiplano: a region highly endemic for human fascioliasis.

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    Mas-Coma, S; Anglés, R; Esteban, J G; Bargues, M D; Buchon, P; Franken, M; Strauss, W

    1999-06-01

    The worldwide importance of human infection by Fasciola hepatica has been recognized in recent years. The endemic region between Lake Titicaca and the valley of La Paz, Bolivia, at 3800-4100 m altitude, presents the highest prevalences and intensities recorded. Large geographical studies involving Lymnaea truncatula snails (malacological, physico-chemical, and botanic studies of 59, 28 and 30 water bodies, respectively, inhabited by lymnaeids; environmental mean temperature studies covering a 40-year period), livestock (5491 cattle) and human coprological surveys (2723 subjects, 2521 of whom were school children) were conducted during 1991-97 to establish the boundaries and distributional characteristics of this endemic Northern Altiplano region. The endemic area covers part of the Los Andes, Ingavi, Omasuyos and Murillo provinces of the La Paz Department. The human endemic zone is stable, isolated and apparently fixed in its present outline, the boundaries being marked by geographical, climatic and soil-water chemical characteristics. The parasite distribution is irregular in the endemic area, the transmission foci being patchily distributed and linked to the presence of appropriate water bodies. Prevalences in school children are related to snail population distribution and extent. Altiplanic lymnaeids mainly inhabit permanent water bodies, which enables parasite transmission during the whole year. A confluence of several factors mitigates the negative effects of the high altitude.

  8. Multilocus Phylogenetics Show High Levels of Endemic Fusaria Inhabiting Sardinian Soils (Tyrrhenian Islands)

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    The Mediterranean island of Sardinia is well known for high levels of vascular plant diversity and endemism, but little is known about its microbial diversity. Under the hypothesis that Fusarium species would show similar patterns, we estimated variability in Fusarium species composition among ten ...

  9. High genetic diversity and population structure in the endangered Canarian endemic Ruta oreojasme (Rutaceae).

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    Meloni, Marilena; Reid, Andrea; Caujapé-Castells, Juli; Soto, Moisés; Fernández-Palacios, José María; Conti, Elena

    2015-10-01

    Insular species are expected to have low genetic diversity, for their populations are often small and isolated, and characterized by restricted gene flow and increased incidence of inbreeding. However, empirical results do not always match this expectation. For example, population genetic analyses of several Canarian endemics, based mainly on allozymes, show levels of genetic diversity exceptionally high for insular species. To investigate whether genetic variation in rare species endemic to Canary Islands is low, as predicted by theoretical expectations, or high, as documented in some previous studies, we analysed genetic diversity of the endangered Ruta oreojasme, a rare endemic of the island of Gran Canaria, using microsatellite markers, which are more variable than allozymes. Our analyses identified very high levels of genetic diversity (A = 7.625, P = 0.984, H o = 0.558, H e = 0.687) for R. oreojasme. Even though the distribution of the species is restricted to the South of Gran Canaria, only one population shows low genetic diversity, isolation and signs of a recent bottleneck/founder event. Some intrinsic characteristics of R. oreojasme (hermaphroditism, proterandry and polyploidy), the relative climatic stability of the Canarian archipelago during Quaternary glacials/interglacials, the size of most populations (thousands of individuals), its age, and the relative proximity of the archipelago to the mainland might have contributed to the high diversity that characterises this endemic. As expected, given the marked topographic complexity of Gran Canaria, we found marked genetic structure in R. oreojasme populations. Our results support the observation that Canarian endemics are characterised by unexpectedly high genetic diversity and provides important insights for potential applications to the conservation of R. oreojasme.

  10. High endemism at cave entrances: a case study of spiders of the genus Uthina

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    Yao, Zhiyuan; Dong, Tingting; Zheng, Guo; Fu, Jinzhong; Li, Shuqiang

    2016-01-01

    Endemism, which is typically high on islands and in caves, has rarely been studied in the cave entrance ecotone. We investigated the endemism of the spider genus Uthina at cave entrances. Totally 212 spiders were sampled from 46 localities, from Seychelles across Southeast Asia to Fiji. They mostly occur at cave entrances but occasionally appear at various epigean environments. Phylogenetic analysis of DNA sequence data from COI and 28S genes suggested that Uthina was grouped into 13 well-supported clades. We used three methods, the Bayesian Poisson Tree Processes (bPTP) model, the Bayesian Phylogenetics and Phylogeography (BPP) method, and the general mixed Yule coalescent (GMYC) model, to investigate species boundaries. Both bPTP and BPP identified the 13 clades as 13 separate species, while GMYC identified 19 species. Furthermore, our results revealed high endemism at cave entrances. Of the 13 provisional species, twelve (one known and eleven new) are endemic to one or a cluster of caves, and all of them occurred only at cave entrances except for one population of one species. The only widely distributed species, U. luzonica, mostly occurred in epigean environments while three populations were found at cave entrances. Additionally, eleven new species of the genus are described. PMID:27775081

  11. High Prevalence of Asymptomatic Neurocysticercosis in an Endemic Rural Community in Peru

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    O’Neal, Seth E.; Ayvar, Viterbo; Gonzalvez, Guillermo; Gamboa, Ricardo; Vilchez, Percy; Rodriguez, Silvia; Reistetter, Joe; Tsang, Victor C. W.; Gilman, Robert H.; Gonzalez, Armando E.; Garcia, Hector H.

    2016-01-01

    Background Neurocysticercosis is a common helminthic infection of the central nervous system and an important cause of adult-onset epilepsy in endemic countries. However, few studies have examined associations between neurologic symptoms, serology and radiographic findings on a community-level. Methodology We conducted a population-based study of resident’s ≥2 years old in a highly endemic village in Peru (pop. 454). We applied a 14 -question neurologic screening tool and evaluated serum for antibodies against Taenia solium cysticercosis using enzyme-linked immunoelectrotransfer blot (LLGP-EITB). We invited all residents ≥18 years old to have non-contrast computerized tomography (CT) of the head. Principal findings Of the 385 residents who provided serum samples, 142 (36.9%) were seropositive. Of the 256 residents who underwent CT scan, 48 (18.8%) had brain calcifications consistent with NCC; 8/48 (17.0%) reported a history of headache and/or seizures. Exposure to T. solium is very common in this endemic community where 1 out of 5 residents had brain calcifications. However, the vast majority of people with calcifications were asymptomatic. Conclusion This study reports a high prevalence of NCC infection in an endemic community in Peru and confirms that a large proportion of apparently asymptomatic residents have brain calcifications that could provoke seizures in the future. PMID:27992429

  12. High water content in primitive continental flood basalts

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    Xia, Qun-Ke; Bi, Yao; Li, Pei; Tian, Wei; Wei, Xun; Chen, Han-Lin

    2016-01-01

    As the main constituent of large igneous provinces, the generation of continental flood basalts (CFB) that are characterized by huge eruption volume (>105 km3) within short time span (basaltic melts and the partition coefficient of H2O between cpx and basaltic melt. The arc-like H2O content (4.82 ± 1.00 wt.%) provides the first clear evidence that H2O plays an important role in the generation of CFB. PMID:27143196

  13. Evolution of high Arctic ocean basins and continental margins

    Energy Technology Data Exchange (ETDEWEB)

    Engen, Oeyvind

    2005-08-01

    Taking advantage of the much increased detail offered by new data, the dissertation attempts to answer some of the remaining questions about the ocean basins and continental margins flanking the Eurasia-North America plate boundary. Its four constituent papers result from integrated geophysical analysis of gravity and magnetic anomalies, bathymetry, seismic reflection and refraction profiles, earthquake locations and focal mechanisms, and onshore and offshore geological data. The overall objectives are to: 1) Elucidate aspects of the structure, composition and evolution of the Eurasia Basin and Norwegian-Greenland Sea and their passive continental margins. 2) Relate the findings to fundamental Earth processes, specifically associated with lithospheric break-up and seafloor spreading. Summary of Papers: The present-day global seismograph network is capable of detecting earthquakes with nearly uniform magnitude threshold throughout the Eurasia Basin region. Given that the location of each earthquake is constrained by at least 12 recording stations, global earthquake catalogues confidently show that 1) earthquakes along the oceanic part of the plate boundary occur in swarms; 2) plate boundary stress decreases eastwards, in accordance with decreasing spreading rates; and 3) deformation takes place in a narrow zone in the oceanic domain but is abruptly defocused at the transition to the Laptev Sea continental rift system. When integrated with bathymetry and potential field data, the earthquake distribution indicates four distinct plate boundary provinces. The Spitsbergen Transform System is a series of oblique ridges and transform faults where the seismicity becomes increasingly diffuse to the north. The western Gakkel Ridge (west of 60{sup E}) has clustered and focused seismicity, accentuated topography and highamplitude magnetic anomalies, whereas the eastern Gakkel Ridge has smoother topographic relief, lower magnetic amplitudes, and slightly more focused seismicity

  14. Acute hepatitis A in an elderly patient after care worker travel to high endemicity country.

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    Aasheim, Erlend T; Seymour, Martin; Balogun, Koye; Ngui, Siew-Lin; Williams, Chris J; Shankar, Ananda Giri

    2013-11-01

    Hepatitis A virus (HAV) is considered one of the most important vaccine-preventable diseases in travelers. HAV spreads from person to person via the fecal-oral route and gives rise to an estimated 1.4 million cases worldwide each year. In developing countries with poor sanitary conditions people tend to be infected during childhood and have few symptoms, whereas in developed countries with good sanitary conditions fewer people develop immunity during childhood. This leads to susceptible populations of adults, who are also more prone to severe complications. Here we describe two confirmed cases of hepatitis A associated with a nursing home. The index case was a care worker who had recently traveled to a high-endemicity country, and the second case was a resident at the nursing home where the index case worked. Both cases had an identical genotype IIIA strain, consistent with a transmission event. Current policy does not include a requirement for hepatitis A vaccine in care workers who travel to high endemicity countries despite the fact that infected care workers can potentially spread the disease to elderly patients and other groups at risk of severe complications from HAV infection. We suggest that employers should consider hepatitis A vaccine upon employment; particularly in care workers who plan to visit areas where HAV is known to be endemic.

  15. Occurrence of free-living amoebae in communities of low and high endemicity for Buruli ulcer in southern Benin.

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    Eddyani, Miriam; De Jonckheere, Johan F; Durnez, Lies; Suykerbuyk, Patrick; Leirs, Herwig; Portaels, Françoise

    2008-11-01

    Buruli ulcer or Mycobacterium ulcerans disease occurs mainly in areas in proximity to standing or slowly running freshwater, habitats in which free-living amoebae occur. For this reason, a possible link between the habitat of M. ulcerans and free-living amoebae was investigated. Free-living amoebae and mycobacteria were isolated from water and biofilm specimens taken from protected and unprotected sources of water in villages known to have either high or low endemicity for Buruli ulcer in Benin. Amoebae were isolated from 78.8% of samples. A greater proportion of water bodies in areas of high endemicity had amoebae than in areas of low endemicity (83.3% versus 66.7%). Protected sources of water were significantly more likely to contain amoebae in areas of high endemicity than in areas of low endemicity (88.0% versus 11.1%). Several pathogenic free-living amoebae and mycobacteria were isolated. However, no M. ulcerans was isolated and no specimen was positive for IS2404 PCR. Our results show that the study area has a water hygiene problem, which is greater in areas of high Buruli ulcer endemicity than in areas of low endemicity. Our observations indicate that additional studies are required to explore the possible link between free-living amoebae and mycobacteria.

  16. High cadmium concentrations in areas with endemic fluorosis: A serious hidden toxin?

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.; Xiao, T.F.; Wang, S.J.; Lei, J.L.; Zhang, M.Z.; Gong, Y.Y.; Li, H.J.; Ning, Z.P.; He, L.B. [Chinese Academy of Sciences, Guiyang (China). Institute of Geochemistry

    2009-07-15

    Environmental contamination with cadmium (Cd) and fluorine (F) and the associated health impacts on humans have raised significant concerns in the literature, but the additional health risks created by Cd have not been investigated in areas with endemic fluorine intoxication (fluorosis). Here, we report for the first time that naturally occurring Cd in areas where endemic fluorosis is related to coal combustion is a serious hidden toxin. The high Cd levels in rocks and soils of these areas may increase health risks to epidemiological level, irrespective of fluorine levels. We implemented a pilot study in a fluorosis-affected rural area within China's Three Gorges region, and revealed enrichment of Cd in local bedrock (4.48-187 mg kg{sup -1}), coal (11.5-53.4 mg kg{sup -1}), and arable soils (1.01-59.7 mg kg{sup -1}). Cadmium was also observed to concentrate in local food crops (0.58-14.9 mg kg{sup -1}) and in the urine of local residents (1.7-13.4 {mu} g L{sup -1}). A routine epidemiological investigation revealed that the two major Cd exposure pathways were through crop consumption and inhalation of emissions from coal combustion. Therefore, the naturally occurring Cd in areas with endemic fluorosis related to coal combustion represents a previously unrecognized toxin that must be addressed as part of efforts to control the endemic problem. The biogeochemical processes of Cd and the associated environmental effects will require additional in-depth study.

  17. Effects of high-severity fire drove the population collapse of the subalpine Tasmanian endemic conifer Athrotaxis cupressoides.

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    Holz, Andrés; Wood, Sam W; Veblen, Thomas T; Bowman, David M J S

    2015-01-01

    Athrotaxis cupressoides is a slow-growing and long-lived conifer that occurs in the subalpine temperate forests of Tasmania, a continental island to the south of Australia. In 1960-1961, human-ignited wildfires occurred during an extremely dry summer that killed many A. cupressoides stands on the high plateau in the center of Tasmania. That fire year, coupled with subsequent regeneration failure, caused a loss of ca. 10% of the geographic extent of this endemic Tasmanian forest type. To provide historical context for these large-scale fire events, we (i) collected dendroecological, floristic, and structural data, (ii) documented the postfire survival and regeneration of A. cupressoides and co-occurring understory species, and (iii) assessed postfire understory plant community composition and flammability. We found that fire frequency did not vary following the arrival of European settlers, and that A. cupressoides populations were able to persist under a regime of low-to-mid severity fires prior to the 1960 fires. Our data indicate that the 1960 fires were (i) of greater severity than previous fires, (ii) herbivory by native marsupials may limit seedling survival in both burned and unburned A. cupressoides stands, and (iii) the loss of A. cupressoides populations is largely irreversible given the relatively high fuel loads of postfire vegetation communities that are dominated by resprouting shrubs. We suggest that the feedback between regeneration failure and increased flammability will be further exacerbated by a warmer and drier climate causing A. cupressoides to contract to the most fire-proof landscape settings.

  18. Impacts of Tropical Forest Disturbance Upon Avifauna on a Small Island with High Endemism: Implications for Conservation

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    Martin Thomas

    2010-01-01

    Full Text Available Tropical forests are rapidly being lost across Southeast Asia and this is predicted to have severe implications for many of the region′s bird species. However, relationships between forest disturbance and avifaunal assemblages remain poorly understood, particularly on small island ecosystems such as those found in the biodiversity ′hotspot′ of Wallacea. This study examines how avifaunal richness varies across a disturbance gradient in a forest reserve on Buton Island, southeast Sulawesi. Particular emphasis is placed upon examining responses in endemic and red-listed species with high conservation importance. Results indicate that overall avian richness increases between primary and 30-year-old regenerating secondary forest and then decreases through disturbed secondary forest, but is highest in cleared farmland. However, high species richness in farmland does not signify high species distinctiveness; bird community composition here differs significantly from that found in forest sites, and is poor in supporting forest specialists and endemic species. Certain large-bodied endemics such as the Knobbed Hornbill (Rhyticeros cassidix appear to be sensitive to moderate disturbance, with populations occurring at greatest density within primary forest. However, overall endemic species richness, as well as that of endemic frugivores and insectivores, is similar in primary and secondary forest types. Results indicate that well-established secondary forest in particular has an important role in supporting species with high conservational importance, possessing community composition similar to that found in primary forest and supporting an equally high richness of endemic species.

  19. Multiplicity and diversity of Plasmodium vivax infections in a highly endemic region in Papua New Guinea.

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    Cristian Koepfli

    2011-12-01

    Full Text Available Plasmodium vivax is highly endemic in the lowlands of Papua New Guinea and accounts for a large proportion of the malaria cases in children less than 5 years of age. We collected 2117 blood samples at 2-monthly intervals from a cohort of 268 children aged 1 to 4.5 years and estimated the diversity and multiplicity of P. vivax infection. All P. vivax clones were genotyped using the merozoite surface protein 1 F3 fragment (msp1F3 and the microsatellite MS16 as molecular markers. High diversity was observed with msp1F3 (H(E = 88.1% and MS16 (H(E = 97.8%. Of the 1162 P. vivax positive samples, 74% harbored multi-clone infections with a mean multiplicity of 2.7 (IQR = 1-3. The multiplicity of P. vivax infection increased slightly with age (P = 0.02, with the strongest increase in very young children. Intensified efforts to control malaria can benefit from knowledge of the diversity and MOI both for assessing the endemic situation and monitoring the effects of interventions.

  20. Biogeography in a continental island: population structure of the relict endemic centipede Craterostigmus tasmanianus (Chilopoda, Craterostigmomorpha) in Tasmania using 16S rRNA and COI.

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    Vélez, Sebastián; Mesibov, Robert; Giribet, Gonzalo

    2012-01-01

    We used 16S ribosomal RNA (rRNA) and cytochrome c oxidase subunit I (COI) sequence data to investigate the population structure in the centipede Craterostigmus tasmanianus Pocock, 1902 (Chilopoda: Craterostigmomorpha: Craterostigmidae) and to look for possible barriers to gene flow on the island of Tasmania, where C. tasmanianus is a widespread endemic. We first confirmed a molecular diagnostic character in 28S rRNA separating Tasmanian Craterostigmus from its sister species Craterostigmus crabilli (Edgecombe and Giribet 2008) in New Zealand and found no shared polymorphism in this marker for the 2 species. In Tasmania, analysis of molecular variance analysis showed little variation at the 16S rRNA and COI loci within populations (6% and 13%, respectively), but substantial variation (56% and 48%, respectively) among populations divided geographically into groups. We found no clear evidence of isolation by distance using a Mantel test. Bayesian clustering and gene network analysis both group the C. tasmanianus populations in patterns which are broadly concordant with previously known biogeographical divisions within Tasmania, but we did not find that genetic distance varied in a simple way across cluster boundaries. The coarse-scale geographical sampling on which this study was based should be followed in the future by sampling at a finer spatial scale and to investigate genetic structure within clusters and across cluster boundaries.

  1. Scoring clinical signs can help diagnose canine visceral leishmaniasis in a highly endemic area in Brazil

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    da Silva, Kleverton Ribeiro; de Mendonça, Vitor Rosa Ramos; Silva, Kellen Matuzzy; do Nascimento, Leopoldo Fabrício Marçal; Mendes-Sousa, Antonio Ferreira; de Pinho, Flaviane Alves; Barral-Netto, Manoel; Barral, Aldina Maria Prado; Cruz, Maria do Socorro Pires e

    2017-01-01

    Canine visceral leishmaniasis (CVL) diagnosis is still a challenge in endemic areas with limited diagnostic resources. This study proposes a score with the potential to distinguish positive CVL cases from negative ones. We studied 265 dogs that tested positive for CVL on ELISA and parasitological tests. A score ranging between 0 and 19 was recorded on the basis of clinical signs. Dogs with CVL had an overall higher positivity of the majority of clinical signs than did dogs without CVL or with ehrlichiosis. Clinical signs such as enlarged lymph nodes (83.93%), muzzle/ear lesions (55.36%), nutritional status (51.79%), bristle condition (57.14%), pale mucosal colour (48.21%), onychogryphosis (58.93%), skin lesion (39.28%), bleeding (12.50%), muzzle depigmentation (41.07%), alopecia (39.29%), blepharitis (21.43%), and keratoconjunctivitis (42.86%) were more frequent in dogs with CVL than in dogs with ehrlichiosis or without CVL. Moreover, the clinical score increased according to the positivity of all diagnostic tests (ELISA, p < 0.001; parasite culture, p = 0.0021; and smear, p = 0.0003). Onychogryphosis (long nails) [odds ratio (OR): 3.529; 95% confidence interval (CI): 1.832-6.796; p < 0.001], muzzle depigmentation (OR: 4.651; 95% CI: 2.218-9.750; p < 0.001), and keratoconjunctivitis (OR: 5.400; 95% CI: 2.549-11.441; p < 0.001) were highly associated with CVL. Interestingly, a score cut-off value ≥ 6 had an area under the curve of 0.717 (p < 0.0001), sensitivity of 60.71%, and specificity of 73.64% for CVL diagnosis. The clinical sign-based score for CVL diagnosis suggested herein can help veterinarians reliably identify dogs with CVL in endemic areas with limited diagnostic resources. PMID:28076469

  2. Transplacental Transmission of Plasmodium falciparum in a Highly Malaria Endemic Area of Burkina Faso

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    Alphonse Ouédraogo

    2012-01-01

    Full Text Available Malaria congenital infection constitutes a major risk in malaria endemic areas. In this study, we report the prevalence of transplacental malaria in Burkina Faso. In labour and delivery units, thick and thin blood films were made from maternal, placental, and umbilical cord blood to determine malaria infection. A total of 1,309 mother/baby pairs were recruited. Eighteen cord blood samples (1.4% contained malaria parasites (Plasmodium falciparum. Out of the 369 (28.2% women with peripheral positive parasitemia, 211 (57.2% had placental malaria and 14 (3.8% had malaria parasites in their umbilical cord blood. The umbilical cord parasitemia levels were statistically associated with the presence of maternal peripheral parasitemia (OR=9.24, ≪0.001, placental parasitemia (OR=10.74, ≪0.001, high-density peripheral parasitemia (OR=9.62, ≪0.001, and high-density placental parasitemia (OR=4.91, =0.03. In Burkina Faso, the mother-to-child transmission rate of malaria appears to be low.

  3. Malaria elimination in Malawi: research needs in highly endemic, poverty-stricken contexts.

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    Wilson, Mark L; Walker, Edward D; Mzilahowa, Themba; Mathanga, Don P; Taylor, Terrie E

    2012-03-01

    Malaria control in the impoverished, highly endemic settings of sub-Saharan Africa remains a major public health challenge. Successes have been achieved only where sustained, concerted, multi-pronged interventions have been instituted. As one of the world's poorest countries, Malawi experiences malaria incidence rates that have remained high despite a decade of gradually expanding and more intensive prevention efforts. The Malawi International Center for Excellence in Malaria Research (ICEMR) is beginning work to augment the knowledge base for reducing Plasmodium transmission and malaria morbidity and mortality. Among ICEMR goals, we intend to better assess patterns of infection and disease, and analyze transmission by Anopheles vector species in both urban and rural ecological settings. We will evaluate parasite population genetics and dynamics, transmission intensities and vector ecologies, social and environmental determinants of disease patterns and risk, and human-vector-parasite dynamics. Such context-specific information will help to focus appropriate prevention and treatment activities on efforts to control malaria in Malawi. In zones of intense and stable transmission, like Malawi, elimination poses particularly thorny challenges - and these challengers are different from those of traditional control and prevention activities. Working toward elimination will require knowledge of how various interventions impact on transmission as it approaches very low levels. At present, Malawi is faced with immediate, context-specific problems of scaling-up prevention and control activities simply to begin reducing infection and disease to tolerable levels. The research required to support these objectives is critically evaluated here.

  4. High Genetic Diversity in a Rare, Narrowly Endemic Primrose Species: Primula interjacens by ISSR Analysis

    Institute of Scientific and Technical Information of China (English)

    XUEDa-Wei; GEXue-Jun; HAOGang; ZHANGChang-Qin

    2004-01-01

    Prirnula interjacens Chen (Primulaceae) is a rare and narrow endemic species of centralsouth of Yunnan Province in China. This species consists of two varieties: P.interjacens var. interjacens known with only one population, and P.interjacens var. epilosa with two populations. Intersimple sequence repeat (ISSR) marker was used to detect the genetic diversity of the three extant populations. We expected a low genetic diversity level, but our results revealed a high level of intraspecific genetic diversity (at population level: P=59.75%, HE=0.2368, and Hpop=0.3459; at species level: P=75.47%, HT= 0.320 5, and Hsp = 0.4618), probably resulting from floral heteromorphism and preferring outcrossing. A moderate level of genetic differentiation among populations was detected based on Nei's genetic diversity analysis (26.13%) and Shannon's diversity index (25.09%). Although P./ntedacens var. intedacens and P. interjacens var. epilosa were morphologically distinct, UPGMA cluster analysis showed that the two varieties had no distinct genetic differentiation and may be treated as a single taxon. Conservation measures are suggested, including in situ and ex situ strategies, based on the observed population genetic information.

  5. Trends of analgesic nephropathy in two high-endemic regions with different legislation.

    Science.gov (United States)

    Michielsen, P; de Schepper, P

    2001-03-01

    Analgesic abuse is related to a specific form of interstitial nephritis, but the exact nature of the causal agent remains controversial and this has resulted in differences in regulation. In Flanders, the free sale of phenacetin was banned, but the consumption of other combined analgesics remained free. In New South Wales, phenacetin was also banned, but 2 yr later the sales of all combined analgesics were also prohibited. This study compared the evolution of end-stage renal disease as a result of analgesic nephropathy (AN) in these two high-endemic regions with different legislation. In both regions, the time trend of the age-specific incidence of end-stage renal disease as a result of AN is similar in the age group 45 to 54 yr. In all age groups combined, the time trend of the percentage of AN among the patients admitted for renal replacement therapy is also similar. This finding does not support the hypothesis that non-phenacetin mixed analgesics play a significant role in the occurrence of AN.

  6. Structural highs on the western continental slope of India: Implications for regional tectonics

    Digital Repository Service at National Institute of Oceanography (India)

    Mukhopadhyay, R.; Rajesh, M.; De, Suritha; Chakraborty, B.; Jauhari, P.

    Transmission(RDT)modetoobtainuniform Fig. 4. The continental slope bathymetry as deduced from multibeam swath contours at 25 m intervals shows the presence of structural highs (white semi-circular patches 01, 04, 05, 08) and a linear depression on the eastern strip considered as Upper... and manual error de- Fig. 5. The 3-Ddigital terrainmodel (DTM) ofa part of thecontinental slope strips are shown. Note the flat summits, steep western and relatively gentle bulged slope wall in the north-central part and a channel-like depression relatively...

  7. High-Resolution Geologic Mapping of the Inner Continental Shelf: Cape Ann to Salisbury Beach, Massachusetts

    Science.gov (United States)

    Barnhardt, Walter A.; Andrews, Brian D.; Ackerman, Seth D.; Baldwin, Wayne E.; Hein, Christopher J.

    2009-01-01

    The geologic framework of the Massachusetts inner continental shelf between Cape Ann and Salisbury Beach has been shaped by a complicated history of glaciation, deglaciation, and changes in relative sea level. New geophysical data (swath bathymetry, sidescan sonar and seismic-reflection profiling), sediment samples, and seafloor photography provide insight into the geomorphic and stratigraphic record generated by these processes. High-resolution spatial data and geologic maps in this report support coastal research and efforts to understand the type, distribution, and quality of subtidal marine habitats in the Massachusetts coastal ocean.

  8. Genotyping of Mycobacterium leprae strains from a region of high endemic leprosy prevalence in India.

    Science.gov (United States)

    Lavania, Mallika; Jadhav, Rupendra; Turankar, Ravindra P; Singh, Itu; Nigam, Astha; Sengupta, U

    2015-12-01

    Leprosy is still a major health problem in India which has the highest number of cases. Multiple locus variable number of tandem repeat analysis (MLVA) and single nucleotide polymorphism (SNP) have been proposed as tools of strain typing for tracking the transmission of leprosy. However, empirical data for a defined population from scale and duration were lacking for studying the transmission chain of leprosy. Seventy slit skin scrapings were collected from Purulia (West Bengal), Miraj (Maharashtra), Shahdara (Delhi), and Naini (UP) hospitals of The Leprosy Mission (TLM). SNP subtyping and MLVA on 10 VNTR loci were applied for the strain typing of Mycobacterium leprae. Along with the strain typing conventional epidemiological investigation was also performed to trace the transmission chain. In addition, phylogenetic analysis was done on variable number of tandem repeat (VNTR) data sets using sequence type analysis and recombinational tests (START) software. START software performs analyses to aid in the investigation of bacterial population structure using multilocus sequence data. These analyses include data summary, lineage assignment, and tests for recombination and selection. Diversity was observed in the cross-sectional survey of isolates obtained from 70 patients. Similarity in fingerprinting profiles observed in specimens of cases from the same family or neighborhood locations indicated a possible common source of infection. The data suggest that these VNTRs including subtyping of SNPs can be used to study the sources and transmission chain in leprosy, which could be very important in monitoring of the disease dynamics in high endemic foci. The present study strongly indicates that multi-case families might constitute epidemic foci and the main source of M. leprae in villages, causing the predominant strain or cluster infection leading to the spread of leprosy in the community.

  9. Epidemiology of hepatitis C virus infection in highly endemic HBV areas in China.

    Directory of Open Access Journals (Sweden)

    Duan Li

    Full Text Available BACKGROUND: Wuwei City has the highest prevalence of hepatitis B virus (HBV in China. From 2007 to 2011, the average reported incidence rate of hepatitis B was 634.56/100,000 people. However, studies assessing the epidemic features and risk factors of HCV in the general population of Wuwei City are limited. METHODS: A total of 7189 people were interviewed and screened for HCV antibodies. HCV RNA and HCV genotypes were analyzed by PCR. Relevant information was obtained from the general population using a standardized questionnaire, and association and logistic regression analyses were conducted. RESULTS: The anti-HCV prevalence was 1.64% (118/7189, and HCV-RNA was detected in 37.29% (44/118 of the anti-HCV positive samples. The current HCV infection rate was 0.61% (44/7189 in the Wuwei general population. Hepatitis C infection rate was generally higher in the plains regions (χ(2 = 27.54,P<0.05, and the most predominant HCV genotypes were 2a (59.1% and 1b (34.1%. The concurrent HCV and HBV infection rate was 1.37%, and a history of blood transfusion (OR = 17.9, 95% CI: 6.1 to 52.6, p<0.001 was an independent risk factor for HCV positivity. CONCLUSIONS: Although Wuwei is a highly endemic area for HBV, the anti-HCV positive rate in the general population is low. More than one-third of HCV-infected people were unaware of their infection; this may become an important risk factor for hepatitis C prevalence in the general population. Maintaining blood safety is important in order to help reduce the burden of HCV infection in developing regions of China.

  10. Latent infection with Leishmania donovani in highly endemic villages in Bihar, India.

    Directory of Open Access Journals (Sweden)

    Epco Hasker

    Full Text Available INTRODUCTION: Asymptomatic persons infected with the parasites causing visceral leishmaniasis (VL usually outnumber clinically apparent cases by a ratio of 4-10 to 1. We describe patterns of markers of Leishmania donovani infection and clinical VL in relation to age in Bihar, India. METHODS: We selected eleven villages highly endemic for Leishmania donovani. During a 1-year interval we conducted two house to house surveys during which we collected blood samples on filter paper from all consenting individuals aged 2 years and above. Samples were tested for anti-leishmania serology by Direct Agglutination Test (DAT and rK39 ELISA. Data collected during the surveys included information on episodes of clinical VL among study participants. RESULTS: We enrolled 13,163 persons; 6.2% were reactive to DAT and 5.9% to rK39. Agreement between the tests was weak (kappa = 0.30. Among those who were negative on both tests at baseline, 3.6% had converted to sero-positive on either of the two tests one year later. Proportions of sero-positives and sero-converters increased steadily with age. Clinical VL occurred mainly among children and young adults (median age 19 years. DISCUSSION: Although infection with L. donovani is assumed to be permanent, serological markers revert to negative. Most VL cases occur at younger ages, yet we observed a steady increase with age in the frequency of sero-positivity and sero-conversion. Our findings can be explained by a boosting effect upon repeated exposure to the parasite or by intermittent release of parasites in infected subjects from safe target cells. A certain proportion of sero-negative subjects could have been infected but below the threshold of antibody abundance for our serologic testing.

  11. Prevalence of Cutaneous Leishmaniasis in Districts of High and Low Endemicity in Mali.

    Directory of Open Access Journals (Sweden)

    Bourama Traoré

    2016-11-01

    Full Text Available Historically the western sahelian dry regions of Mali are known to be highly endemic for cutaneous leishmaniasis (CL caused by Leishmania major, while cases are rarely reported from the Southern savanna forest of the country. Here, we report baseline prevalence of CL infection in 3 ecologically distinct districts of Mali (dry sahelian, north savanna and southern savanna forest areas. We screened 195 to 250 subjects from 50 to 60 randomly selected households in each of the 6 villages (four from the western sahelian district of Diema in Kayes region, one from the central district of Kolokani and one from the southern savanna district of Kolodieba, region of Sikasso. The screening consisted of: 1] A Leishmanin Skin Test (LST for detection of exposure to Leishmania parasites; 2] clinical examination of suspected lesions, followed by validation with PCR and 3] finger prick blood sample to determine antibody levels to sand fly saliva. LST positivity was higher in the western district of Diema (49.9% than in Kolokani (24.9% and was much lower in Kolondieba (2.6%. LST positivity increased with age rising from 13.8% to 88% in Diema for age groups 2-5 years and 41-65 years, respectively. All eight PCR-confirmed L. major CL cases were diagnosed in subjects below 18 years of age and all were residents of the district of Diema. Exposure to sand fly bites, measured by anti-saliva antibody titers, was comparable in individuals living in all three districts. However, antibody titers were significantly higher in LST positive individuals (P<0.0001. In conclusion, CL transmission remains active in the western region of Mali where lesions were mainly prevalent among children under 18 years old. LST positivity correlated to higher levels of antibodies to sand fly salivary proteins, suggesting their potential as a risk marker for CL acquisition in Mali.

  12. High Rate of Strongyloidosis Infection, Out of Endemic Area, in Patients with Eosinophilia and without Risk of Exogenous Reinfections

    OpenAIRE

    2010-01-01

    Strongyloides stercoralis chronic infections are usually asymptomatic and underestimated. We used direct fresh stool examination, Ritchie's method, and agar plate culture for diagnosis in patients with eosinophilia and previous residence in endemic areas. The frequency of strongyloidosis detected among these patients was high: 21 of 42 were positive. Among them, 10 were positive only by agar plate culture. After ivermectin treatment, patients resulted negative for parasitological tests and re...

  13. Plant and animal endemism in the eastern Andean slope: challenges to conservation.

    Science.gov (United States)

    Swenson, Jennifer J; Young, Bruce E; Beck, Stephan; Comer, Pat; Córdova, Jesús H; Dyson, Jessica; Embert, Dirk; Encarnación, Filomeno; Ferreira, Wanderley; Franke, Irma; Grossman, Dennis; Hernandez, Pilar; Herzog, Sebastian K; Josse, Carmen; Navarro, Gonzalo; Pacheco, Víctor; Stein, Bruce A; Timaná, Martín; Tovar, Antonio; Tovar, Carolina; Vargas, Julieta; Zambrana-Torrelio, Carlos M

    2012-01-27

    completely outside of national protected areas. Protected areas cover only 20% of areas of high endemism and 20% of irreplaceable areas. Almost 40% of the 91 ecological systems are in serious need of protection (= < 2% of their ranges protected). We identify for the first time, areas of high endemic species concentrations and high irreplaceability that have only been roughly indicated in the past at the continental scale. We conclude that new complementary protected areas are needed to safeguard these endemics and ecosystems. An expansion in protected areas will be challenged by geographically isolated micro-endemics, varied endemic patterns among taxa, increasing deforestation, resource extraction, and changes in climate. Relying on pre-existing collections, publically accessible datasets and tools, this working framework is exportable to other regions plagued by incomplete conservation data.

  14. Plant and animal endemism in the eastern Andean slope: challenges to conservation

    Directory of Open Access Journals (Sweden)

    Swenson Jennifer J

    2012-01-01

    third of endemic species have distributions completely outside of national protected areas. Protected areas cover only 20% of areas of high endemism and 20% of irreplaceable areas. Almost 40% of the 91 ecological systems are in serious need of protection (= Conclusions We identify for the first time, areas of high endemic species concentrations and high irreplaceability that have only been roughly indicated in the past at the continental scale. We conclude that new complementary protected areas are needed to safeguard these endemics and ecosystems. An expansion in protected areas will be challenged by geographically isolated micro-endemics, varied endemic patterns among taxa, increasing deforestation, resource extraction, and changes in climate. Relying on pre-existing collections, publically accessible datasets and tools, this working framework is exportable to other regions plagued by incomplete conservation data.

  15. Plant and animal endemism in the eastern Andean slope: challenges to conservation

    Science.gov (United States)

    2012-01-01

    distributions completely outside of national protected areas. Protected areas cover only 20% of areas of high endemism and 20% of irreplaceable areas. Almost 40% of the 91 ecological systems are in serious need of protection (= < 2% of their ranges protected). Conclusions We identify for the first time, areas of high endemic species concentrations and high irreplaceability that have only been roughly indicated in the past at the continental scale. We conclude that new complementary protected areas are needed to safeguard these endemics and ecosystems. An expansion in protected areas will be challenged by geographically isolated micro-endemics, varied endemic patterns among taxa, increasing deforestation, resource extraction, and changes in climate. Relying on pre-existing collections, publically accessible datasets and tools, this working framework is exportable to other regions plagued by incomplete conservation data. PMID:22284854

  16. High-resolution Continental Scale Land Surface Model incorporating Land-water Management in United States

    Science.gov (United States)

    Shin, S.; Pokhrel, Y. N.

    2016-12-01

    Land surface models have been used to assess water resources sustainability under changing Earth environment and increasing human water needs. Overwhelming observational records indicate that human activities have ubiquitous and pertinent effects on the hydrologic cycle; however, they have been crudely represented in large scale land surface models. In this study, we enhance an integrated continental-scale land hydrology model named Leaf-Hydro-Flood to better represent land-water management. The model is implemented at high resolution (5km grids) over the continental US. Surface water and groundwater are withdrawn based on actual practices. Newly added irrigation, water diversion, and dam operation schemes allow better simulations of stream flows, evapotranspiration, and infiltration. Results of various hydrologic fluxes and stores from two sets of simulation (one with and the other without human activities) are compared over a range of river basin and aquifer scales. The improved simulations of land hydrology have potential to build consistent modeling framework for human-water-climate interactions.

  17. Electrocardiographic findings in Mexican chagasic subjects living in high and low endemic regions of Trypanosoma cruzi infection

    Directory of Open Access Journals (Sweden)

    Francisca Sosa-Jurado

    2003-07-01

    Full Text Available In México the first human chronic chagasic case was recognized in 1940. In spite of an increasing number of cases detected since that time, Chagas disease in México has been poorly documented. In the present work we studied 617 volunteers subjects living in high and low endemic regions of Trypanosoma cruzi infection with seroprevalence of 22% and 4% respectively. Hemoculture performed in those seropositive subjects failed to demonstrate circulating parasites, however polymerase chain reaction identified up to 60% of them as positives. A higher level of anti-T. cruzi antibodies was observed in seropositive residents in high endemic region, in spite of similar parasite persistence (p < 0.05. On standard 12 leads electrocardiogram (ECG 20% to 22% seropositive individuals from either region showed right bundle branch block or ventricular extrasystoles which were more prevalent in seropositive than in seronegative individuals (p < 0.05. In conclusion, the frequency or type of ECG abnormality was influenced by serologic status but not by endemicity or parasite persistence. Furthermore, Mexican indeterminate patients have a similar ECG pattern to those reported in South America.

  18. Prolonged post-rift magmatism on highly extended crust of divergent continental margins (Baiyun Sag, South China Sea)

    Science.gov (United States)

    Zhao, Fang; Alves, Tiago M.; Wu, Shiguo; Li, Wei; Huuse, Mads; Mi, Lijun; Sun, Qiliang; Ma, Benjun

    2016-07-01

    Three-dimensional (3D) seismic, borehole and geochemical data reveal a prolonged phase of post-rift magmatism on highly extended crust of the Baiyun Sag, South China Sea. Two volcanic complexes are identified and described in the context of continental rifting and diachronous continental breakup of the South China Sea. Biostratigraphic data from exploration wells BY7-1 and BY2, complemented by K-Ar datings from core samples, confirm that magmatic activity in the Baiyun Sag occurred in two main stages: (1) a first episode at the base of the Miocene (23.8 Ma); and (2) a second episode occurring at the end of the Early Miocene (17.6 Ma). The relative location of volcanic complexes in the Baiyun Sag, and their stratigraphic position, reveals prolonged magmatism inboard of the ocean-continent transition zone during continental breakup. We suggest that magmatism in the Baiyun Sag reflects progressive continental breakup in the South China Sea, with the last volcanic episode marking the end of a breakup sequence representing the early post-rift tectonic events associated with the continental breakup process. Seismic and borehole data from this breakup sequence records diachronous magma emplacement and complex changes in depositional environments during continental breakup.

  19. High diversity and suggested endemicity of culturable Actinobacteria in an extremely oligotrophic desert oasis

    Directory of Open Access Journals (Sweden)

    Hector Fernando Arocha-Garza

    2017-05-01

    shows that our isolation effort produced 38 unique OTUs in six new monophyletic clades. This high biodiversity and uniqueness of Actinobacteria in an extreme oligotrophic environment, which has previously been reported for its diversity and endemicity, is a suggestive sign of microbial biogeography of Actinobacteria and it also represents an invaluable source of biological material for future ecological and bioprospecting studies.

  20. High diversity and suggested endemicity of culturable Actinobacteria in an extremely oligotrophic desert oasis.

    Science.gov (United States)

    Arocha-Garza, Hector Fernando; Canales-Del Castillo, Ricardo; Eguiarte, Luis E; Souza, Valeria; De la Torre-Zavala, Susana

    2017-01-01

    isolation effort produced 38 unique OTUs in six new monophyletic clades. This high biodiversity and uniqueness of Actinobacteria in an extreme oligotrophic environment, which has previously been reported for its diversity and endemicity, is a suggestive sign of microbial biogeography of Actinobacteria and it also represents an invaluable source of biological material for future ecological and bioprospecting studies.

  1. Risk factors associated with Chagas disease in pregnant women in Santander, a highly endemic Colombian area.

    Science.gov (United States)

    Castellanos-Domínguez, Yeny Z; Cucunubá, Zulma M; Orozco, Luis C; Valencia-Hernández, Carlos A; León, Cielo M; Florez, Astrid C; Muñoz, Lyda; Pavía, Paula; Montilla, Marleny; Uribe, Luz Marina; García, Carlos; Ardila, William; Nicholls, Rubén Santiago; Puerta, Concepción J

    2016-01-01

    To determine the prevalence and risk factors associated with Chagas disease in pregnant women in an endemic area of Santander, Colombia. Cross-sectional study included 23 municipalities of Santander, Colombia. Serological IFAT and ELISA tests were undertaken to detect IgG anti- Trypanosoma cruzi. A questionnaire was conducted for assessing the risk factors of each participant. Newborns were evaluated at birth and followed up to 1 year of age to determine congenital infection. An overall prevalence of 3.2% (95% CI 2.4-4.2) among 1518 pregnant women was detected. Prevalences by provinces were as follows: Guanentina: 6.0% (95% CI 4.1-8.5), García Rovira: 2.9% (95% CI: 1.5-4.8) and Comunera: 0.4% (0.4-2.3). The main risk factors identified were age >32 years old (OR: 2.1; 95% CI: 1.1-3.9); currently having a thatched roof (OR: 11.8; CI95% 2.2-63.2) and a thatched roof during childhood (OR: 3.0; 95% CI: 1.4-6.6); having below primary school education level (OR: 4.6; 95% CI: 2.2-9.5); and a history of a close contact with the vector (triatomine bugs) at least once during their lifetime (OR: 6.9; 95% CI: 3.7-12.9). No congenital cases were detected by parasitological or serological techniques. Prevalence of Chagas disease in pregnant women is a potential source of infection in this Colombian endemic area. The main risk factors associated with seropositivity were related to conditions favouring the contact with the vector. The results show that it is necessary to continue an active surveillance in order to offer diagnosis and treatment to mothers and their newborns in addition to screening to pregnant women from endemic areas. © 2015 John Wiley & Sons Ltd.

  2. On the relationship between sequential faulting, margin asymmetry and highly thinned continental crust

    Science.gov (United States)

    Brune, Sascha; Heine, Christian; Pérez-Gussinyé, Marta; Sobolev, Stephan

    2014-05-01

    The architecture of magma-poor continental margins is remarkably variable. The width of highly thinned continental crust (with a thickness material; (2) Formation of a low viscosity exhumation channel adjacent to the rift centre that is generated by heat transfer from the upwelling mantle and enhanced by viscous strain softening. Rift migration takes place in a steady-state manner and is accomplished by oceanward-younging sequential faults within the upper crust and balanced through lower crustal flow. We demonstrate that the rate of extension has paramount control on margin width. Since higher velocities lead to elevated heat flow within the rift and hence to hot and weak lower crust, a larger low-viscosity exhumation channel is generated that facilitates rift migration leading to wider margins. The South Atlantic is an ideal test bed for the hypothesis of velocity-dependent margin width since rifting was fast in the south, but slow in the northern part. As predicted by our numerical models, the maximum present-day margin width increases almost linearly from the conjugate Equatorial margin segments to the Florianopolis/Walvis ridge. Even though the polarity of the magma-poor South Atlantic margins alternates, the asymmetry and the width of the wider margin are in very good agreement with our simulations. The described rift evolution has three fundamental implications: (1) It implies sustained transfer of material across the extensional plate boundary thereby predicting that large portions of a wide margin originate from its conjugate side. (2) Migration of the deformation locus causes faulting in the distal parts of the margin to postdate that of the proximal parts by as much as 10 million years. This means that syn-rift and post-rift phase are location-dependent. (3) Lateral movement of the rift centre generates drastically different peak heat flow and subsidence histories at the proximal and the distal margin.

  3. Bighorn Basin Coring Project (BBCP): High-Resolution Continental Records of Early Paleogene Hyperthermals

    Science.gov (United States)

    Clyde, W.; Wing, S.; Gingerich, P.

    2012-04-01

    Hyperthermals like the Paleocene-Eocene Thermal Maximum (PETM) are transient global warming events associated with large negative carbon isotope excursions (CIEs) that may serve as analogs to present-day climate change. Determining the causes and effects of hyperthermals is important for understanding the long-term carbon cycle and its effects on other parts of the Earth system. Most detailed stratigraphic records of hyperthermals come from marine sediment cores (e.g. IODP) with relatively few well-resolved continental stratigraphic records available. The Bighorn Basin is an intermontane basin that formed during the Laramide orogeny and experienced rapid subsidence and aggradational fluvial deposition from the early Paleocene through the early Eocene (~65-50 million years ago). It preserves the most complete early Paleogene continental sequence in the world and includes an approximately 40-meter-thick PETM interval During the summer of 2011, over 900 meters of core were recovered as part of the Bighorn Basin Coring Project (BBCP). Two 6.2-cm diameter overlapping cores were drilled at each of three sites. Two of the sites (Basin Substation and Polecat Bench) target the PETM in different environments, and the third site (Gilmore Hill) targets the younger and smaller hyperthermals known as ETM2 and H2. The BBCP cores make it possible to develop high-resolution (circa 1000-year) proxy records of climate change, carbon cycling, and biotic change from unweathered material to investigate the response of a terrestrial depositional and ecological system to extreme global warming events. The coring localities are also distributed along a transect from the margin to the axis of the basin to compare the tectonic and depositional effects on the hyperthermal records. Down-hole logs, multi-sensor core logs (magnetic susceptibility and color reflectance), visual core descriptions, and preliminary isotopic samples will be evaluated, with special emphasis on correlation to previous

  4. Confirmed local endemicity and putative high transmission of Schistosoma mansoni in the Sesse Islands, Lake Victoria, Uganda

    Directory of Open Access Journals (Sweden)

    Kabatereine Narcis B

    2011-03-01

    Full Text Available Abstract The Sesse Islands, in the Ugandan portion of Lake Victoria, have long been considered a low transmission zone for intestinal schistosomiasis. Based on observations of high prevalence of Schistosoma mansoni infection in the northern-most islands of this archipelago, a follow-up survey was conducted to ascertain whether transmission was endemic to this island group, combining parasitological and malacological surveys. Prevalence of intestinal schistosomiasis was again observed to be high, as was intensity of infections which, combined with low reported incidence of treatment, suggests that chemotherapy-based control initiatives are not being maximally effective in this region as high levels of population movement between islands and districts are confounding. The local disease transmission was confirmed by the observations of high abundance of Biomphalaria, as well as field-caught snails shedding S. mansoni cercariae. DNA sequencing of 12 cercariae revealed common mitochondrial cox1 haplotypes, as well as, novel ones, consistent with the high genetic diversity of this parasite in Lake Victoria. Intestinal schistosomiasis is firmly endemic in parts of the Sesse Islands and more broadly, this island group provides an insight into the future challenges to be faced by the Ugandan National Control Programme in regularly reaching these rather remote, inaccessible and largely itinerant communities.

  5. Limited contemporary gene flow and high self-replenishment drives peripheral isolation in an endemic coral reef fish.

    Science.gov (United States)

    van der Meer, Martin H; Horne, John B; Gardner, Michael G; Hobbs, Jean-Paul A; Pratchett, Morgan; van Herwerden, Lynne

    2013-06-01

    Extensive ongoing degradation of coral reef habitats worldwide has lead to declines in abundance of coral reef fishes and local extinction of some species. Those most vulnerable are ecological specialists and endemic species. Determining connectivity between locations is vital to understanding recovery and long-term persistence of these species following local extinction. This study explored population connectivity in the ecologically-specialized endemic three-striped butterflyfish (Chaetodon tricinctus) using mt and msatDNA (nuclear microsatellites) to distinguish evolutionary versus contemporary gene flow, estimate self-replenishment and measure genetic diversity among locations at the remote Australian offshore coral reefs of Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI), and Norfolk Island (NI). Mt and msatDNA suggested genetic differentiation of the most peripheral location (NI) from the remaining three locations (MR, ER, LHI). Despite high levels of mtDNA gene flow, there is limited msatDNA gene flow with evidence of high levels of self-replenishment (≥76%) at all four locations. Taken together, this suggests prolonged population recovery times following population declines. The peripheral population (NI) is most vulnerable to local extinction due to its relative isolation, extreme levels of self-replenishment (95%), and low contemporary abundance.

  6. Tools for Virtual Collaboration Designed for High Resolution Hydrologic Research with Continental-Scale Data Support

    Science.gov (United States)

    Duffy, Christopher; Leonard, Lorne; Shi, Yuning; Bhatt, Gopal; Hanson, Paul; Gil, Yolanda; Yu, Xuan

    2015-04-01

    Using a series of recent examples and papers we explore some progress and potential for virtual (cyber-) collaboration inspired by access to high resolution, harmonized public-sector data at continental scales [1]. The first example describes 7 meso-scale catchments in Pennsylvania, USA where the watershed is forced by climate reanalysis and IPCC future climate scenarios (Intergovernmental Panel on Climate Change). We show how existing public-sector data and community models are currently able to resolve fine-scale eco-hydrologic processes regarding wetland response to climate change [2]. The results reveal that regional climate change is only part of the story, with large variations in flood and drought response associated with differences in terrain, physiography, landuse and/or hydrogeology. The importance of community-driven virtual testbeds are demonstrated in the context of Critical Zone Observatories, where earth scientists from around the world are organizing hydro-geophysical data and model results to explore new processes that couple hydrologic models with land-atmosphere interaction, biogeochemical weathering, carbon-nitrogen cycle, landscape evolution and ecosystem services [3][4]. Critical Zone cyber-research demonstrates how data-driven model development requires a flexible computational structure where process modules are relatively easy to incorporate and where new data structures can be implemented [5]. From the perspective of "Big-Data" the paper points out that extrapolating results from virtual observatories to catchments at continental scales, will require centralized or cloud-based cyberinfrastructure as a necessary condition for effectively sharing petabytes of data and model results [6]. Finally we outline how innovative cyber-science is supporting earth-science learning, sharing and exploration through the use of on-line tools where hydrologists and limnologists are sharing data and models for simulating the coupled impacts of catchment

  7. Teleseismic body wave tomography within a highly extended continental rift: the Woodlark Rift, Papua New Guinea

    Science.gov (United States)

    Eilon, Z.; Abers, G. A.; Jin, G.; Kim, Y.; Gaherty, J. B.

    2013-12-01

    The Woodlark Rift, Papua New Guinea, has been a region of westward-propagating continental extension for 6-8 Ma, grading westward from seafloor spreading to newly thinned continent. The D'Entrecasteaux Islands (DIs) lie immediately to the west of the youngest spreading centres in continental crust that has undergone 140-190 km of extension. These islands are dominated by metamorphic core complexes (MCCs) containing 5-6 Ma ultra-high pressure (UHP) coesite-eclogite exhumed at ~20 mm/yr coeval with extension. An array of 31 PASSCAL broadband seismometers and 8 broadband OBSs was installed around the region from 2010-2011 to investigate the thinned continent close to the onset of seafloor spreading. We present results of a teleseismic P- and S- wave tomography study that images the mantle beneath the rapidly extending continent. Preliminary observations include strong azimuthal dependence of differential travel times, indicating significant lateral velocity variations and inferred thermal gradients. Using Ps receiver functions and SsPmP reflections, we estimate variations in Moho depth to correct for the crustal effect on travel times. We observe large (>1s) travel time delays beneath the DIs in both P and S arrivals, while stations on the Trobriand Islands and Papuan Peninsula exhibit travel time deficits of 1-2 s. This indicates that lithosphere is thinnest beneath the DIs, along the axis of the rift, in agreement with the location of Quaternary volcanism and consistent with results from surface waves [Ge et al., AGU2013 abstract] and a previous, lower-resolution tomographic study nearby. There is also evidence for moderately thinned lithosphere in the basin immediately south of the DIs. We have previously established strong, spreading-parallel anisotropy from SKS splitting caused by mantle olivine fabric beneath the DIs and the Trobriand Platform, inferred to represent asthenospheric flow in response to rifting. Detailed tomography will reveal how thinning of

  8. Slides and debris flows on the high-latitude continental slopes of Baffin Bay

    Science.gov (United States)

    Aksu, A. E.; Hiscott, R. N.

    1989-10-01

    The eastern continental margin of Baffin Island around Ocean Drilling Program (ODP) Site 645 was surveyed by using single-channel airgun, high-resolution boomer systems and piston cores. The data show that much of the upper slope between the 300 and ˜1200 m isobaths is erosional. Major sliding and rotational slumping has removed several hundred metres of sediment from the upper slope, giving the sea bed a steplike morphology. From ˜1200 m to the 2300 m isobath, the slope is constructional and is characterized by abundant acoustically transparent lenses, some of which are traced upslope into acoustically transparent to internally deformed wedge-shaped bodies. These lenses are interpreted to be debris-flow deposits and their abundance in the lower slope indicates frequent upper slope failures. The wedge-shaped bodies are much less common and are interpreted to be larger slides and/or slumps. Near the base of the slope, fields of diapiric structures pierce the acoustically well stratified section and locally produce small mounds on the sea floor. On the basis of correlation with ODP Site 645, they are interpreted as mud diapirs. The combined data show that the lower slope of Baffin Island is constructed predominantly of shingled lenses of debris-flow deposits and rotated slump blocks that originated from major erosion of the upper slope.

  9. Climate change and West Nile virus in a highly endemic region of North America.

    Science.gov (United States)

    Chen, Chen C; Jenkins, Emily; Epp, Tasha; Waldner, Cheryl; Curry, Philip S; Soos, Catherine

    2013-07-22

    The Canadian prairie provinces of Manitoba, Saskatchewan, and Alberta have reported the highest human incidence of clinical cases of West Nile virus (WNV) infection in Canada. The primary vector for WVN in this region is the mosquito Culex tarsalis. This study used constructed models and biological thresholds to predict the spatial and temporal distribution of Cx. tarsalis and WNV infection rate in the prairie provinces under a range of potential future climate and habitat conditions. We selected one median and two extreme outcome scenarios to represent future climate conditions in the 2020 (2010-2039), 2050 (2040-2069) and 2080 (2070-2099) time slices. In currently endemic regions, the projected WNV infection rate under the median outcome scenario in 2050 raised 17.91 times (ranged from 1.29-27.45 times for all scenarios and time slices) comparing to current climate conditions. Seasonal availability of Cx. tarsalis infected with WNV extended from June to August to include May and September. Moreover, our models predicted northward range expansion for Cx. tarsalis (1.06-2.56 times the current geographic area) and WNV (1.08-2.34 times the current geographic area). These findings predict future public and animal health risk of WNV in the Canadian prairie provinces.

  10. Climate Change and West Nile Virus in a Highly Endemic Region of North America

    Directory of Open Access Journals (Sweden)

    Catherine Soos

    2013-07-01

    Full Text Available The Canadian prairie provinces of Manitoba, Saskatchewan, and Alberta have reported the highest human incidence of clinical cases of West Nile virus (WNV infection in Canada. The primary vector for WVN in this region is the mosquito Culex tarsalis. This study used constructed models and biological thresholds to predict the spatial and temporal distribution of Cx. tarsalis and WNV infection rate in the prairie provinces under a range of potential future climate and habitat conditions. We selected one median and two extreme outcome scenarios to represent future climate conditions in the 2020 (2010–2039, 2050 (2040–2069 and 2080 (2070–2099 time slices. In currently endemic regions, the projected WNV infection rate under the median outcome scenario in 2050 raised 17.91 times (ranged from 1.29–27.45 times for all scenarios and time slices comparing to current climate conditions. Seasonal availability of Cx. tarsalis infected with WNV extended from June to August to include May and September. Moreover, our models predicted northward range expansion for Cx. tarsalis (1.06–2.56 times the current geographic area and WNV (1.08–2.34 times the current geographic area. These findings predict future public and animal health risk of WNV in the Canadian prairie provinces.

  11. Climate vs. topography – spatial patterns of plant species diversity and endemism on a high-elevation island

    DEFF Research Database (Denmark)

    Irl, Severin David Howard; Harter, David E. V.; Steinbauer, Manuel

    2015-01-01

    the independent contribution of climatic and topographic variables to spatial diversity patterns. We constructed a presence/absence matrix of perennial endemic and native vascular plant species (including subspecies) in 890 plots on the environmentally very heterogeneous island of La Palma, Canary Islands...... (micro-refugia, in situ speciation, pre-adaptation to rupicolous conditions, dispersal limitations) to human-induced influences (introduced herbivores, fire, land use) that possibly shape the endemic richness pattern of La Palma. In contrast, climate mainly drives endemicity, which is connected...... to ecological speciation and specialization to local conditions. We highlight the importance of incorporating climatic variability into future studies of plant species diversity and endemism. The spatial incongruence in hot spots of species richness, endemic richness and endemicity emphasizes the need...

  12. Deer exposed to exceptionally high concentrations of lead near the continental mine in Idaho, USA

    Science.gov (United States)

    Beyer, W.N.; Gaston, G.; Brazzle, R.; O'Connell, A.F.; Audet, D.J.

    2007-01-01

    Habitat surrounding the inactive Continental Mine in northern Idaho, USA, supports bear (Ursus arctos, Ursus americanus), moose (Alces alces), elk (Cervus elaphus), woodland caribou (Rangifer tarandus caribou), and abundant mule (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus). Tailings on the mining site were capped and remediated in 2003 to reduce environmental exposure of surrounding soil and sediments of Blue Joe Creek, downslope of the mine. Before capping, the mean Pb concentration in deer pellets collected on-site was 920 mg/kg of Pb (dry wt). This exposure, if chronic, would be comparable to an exposure that could be lethal to cattle or horses. Surprisingly, the mean pellet Pb concentration of 950 mg/kg in 2004 was as high as it was before remediation, and it was related to a high rate of soil ingestion. Mean soil content of the pellets collected from the capped site in 2004 was 22% dry weight, estimated from the acid-insoluble ash, a marker of soil ingestion. Clumps of sand and bits of rock were observed inside some of the pellets, and Pb concentrations in the pellets were correlated (p soil content. Although terrestrial risk assessments generally estimate exposure from diets and from incidentally ingested soil, the deer at this site were directly ingesting contaminated soil or mining waste. The mean Pb concentration of this ingested soil was estimated as 6,700 mg/kg and the maximum as 25,000 mg/kg, well above the Pb concentrations measured in the remediated cap. The deer seemed to be ingesting soil or mining waste from one or more small but highly contaminated sources located beyond the remediated cap.

  13. High rate of strongyloidosis infection, out of endemic area, in patients with eosinophilia and without risk of exogenous reinfections.

    Science.gov (United States)

    Repetto, Silvia A; Durán, Pablo A; Lasala, María B; González-Cappa, Stella M

    2010-06-01

    Strongyloides stercoralis chronic infections are usually asymptomatic and underestimated. We used direct fresh stool examination, Ritchie's method, and agar plate culture for diagnosis in patients with eosinophilia and previous residence in endemic areas. The frequency of strongyloidosis detected among these patients was high: 21 of 42 were positive. Among them, 10 were positive only by agar plate culture. After ivermectin treatment, patients resulted negative for parasitological tests and reduced their eosinophil counts. Half of the submitted patients that were followed 4-12 months after treatment remained negative without eosinophilia, except one who showed an eosinophil ascending curve before reappearance of larvae in stools. The high frequency of strongyloidosis found in this group emphasizes the relevance of including this parasitosis among differential diagnosis in patients with eosinophilia and past risk of S. stercoralis infection to prevent disseminated infections secondary to corticoid therapy.

  14. Changing Pattern of Hepatitis A Virus Epidemiology in an Area of High Endemicity

    Directory of Open Access Journals (Sweden)

    Marcello Campagna

    2012-06-01

    Full Text Available Background: Continuous assessment of hepatitis A virus (HAV seroepidemiology is a useful tool to control the risk of infection.Objectives:This study aimed to evaluate the changing patterns of anti-HAV seroprevalence in a population,which isgenerally considered to be anarea ofhigh endemicity.Patients and Methods: Overall, the results of 3349 sera collected during the period 2005-2008 from patients attending the University Hospital of Cagliari, Italy were studied; their mean age was 52.7 years, (s + 16.22. Patients with liver disease were excluded from the study. Age specific seroprevalence results were compared with those observed in similar previous studies carried out in the same area.Results: The overall prevalence of anti-HAV was 74.6% with consistently lower values in subjects younger than 40 years (17.5%; P < 0.0001 particularly in those under 30 years of age (8.9%, CI 5.8-11.9. A significant declining trend in age specific seroprevalence has been foundin people under 30 years;61% in 1988, 33% in 1995 and 8.9% in 2005-2008.Conclusions: Our findings show that a significant decline inherd immunity has occurred in the last 20 years as a consequence of lower HAV circulation due to improvementsin socio-economical and hygienic conditions. Adolescents and young adults are becoming increasingly susceptible to HAV infections, as recent outbreaks of acute HAV hepatitis have occurred. Persistent environmental monitoring and the implementation of prevention measures must be considered in order to contain the risk related to this epidemiological shift..

  15. Prevalence of G6PD deficiency in selected populations from two previously high malaria endemic areas of Sri Lanka

    Science.gov (United States)

    Kapilananda, G. M. G.; Samarakoon, Dilhani; Maddevithana, Sashika; Wijesundera, Sulochana; Goonaratne, Lallindra V.; Karunaweera, Nadira D.

    2017-01-01

    Glucose-6-Phosphate Dehydrogenase (G6PD) enzyme deficiency is known to offer protection against malaria and an increased selection of mutant genes in malaria endemic regions is expected. However, anti-malarial drugs such as primaquine can cause haemolytic anaemia in persons with G6PD deficiency. We studied the extent of G6PD deficiency in selected persons attending Teaching Hospitals of Anuradhapura and Kurunegala, two previously high malaria endemic districts in Sri Lanka. A total of 2059 filter-paper blood spots collected between November 2013 and June 2014 were analysed for phenotypic G6PD deficiency using the modified WST-8/1-methoxy PMS method. Each assay was conducted with a set of controls and the colour development assessed visually as well as with a microplate reader at OD450-630nm. Overall, 142/1018 (13.95%) and 83/1041 (7.97%) were G6PD deficient in Anuradhapura and Kurunegala districts respectively. The G6PD prevalence was significantly greater in Anuradhapura when compared to Kurunegala (P0.05). Severe deficiency (<10% normal) was seen among 28/1018 (2.75%) in Anuradhapura (7 males; 21 females) and 17/1041 (1.63%) in Kurunegala (7 males; 10 females). Enzyme activity between 10–30% was observed among 114/1018 (11.20%; 28 males; 86 females) in Anuradhapura while it was 66/1041 (6.34%; 18 males; 48 females) in Kurunegala. Screening and educational programmes for G6PD deficiency are warranted in these high risk areas irrespective of gender for the prevention of disease states related to this condition. PMID:28152025

  16. Preliminary results of high resolution magneto-biostratigraphy of continental sequences in Chapala Basin, Southwestern Mexico

    Science.gov (United States)

    Mendez Cardenas, D. L.; Benammi, M.

    2007-05-01

    Chapala Lake is south from Guadalajara, Jalisco State (Southwestern Mexico). Belongs to a series of Pliocenic lakes along the Mexican Volcanic Belt. It is localized in the Chapala rift, and the entire area is controlled by the tectonic setting of the Colima, Tepic and Chapala rifts, constituting the triple junction rift-rift-rift. The deposits studied belong to volcanosedimentary sequences, composed by lacustrine and fluvial associations alternated with units of ash and pumice. The faunistic component reported consists at least of 27 mammals species, and the sediments were there're in have to work with special attention for seek rodents by handpicking. Probably these rodents will be the clue to determine the deposits correlation. Core demagnetization shows that they are low-coercivity magnetic minerals like magnetite or Ti-magnetite. It was verified that the characteristic magnetization corresponds to MNRp and the inversion test resulted good. Rodents are represented by Geomynae, Sigmondontinae and Sciurinae. The Geomynae family is the most common, and the faunistic association indicates Blancan age. This also allows a correlation with the polarity pattern in the GSS between 3,6 and 2,6 Ma. Actually, is known that this kind of studies in continental sequences supported with paleontological record of vertebrates could give us a more precised calibration of the age of such deposits. Allowing better understanding of the evolution of these mammals and their path trough geological record. This work shows the preliminary results of rodents palaeontology and high resolution magneto-stratigraphy in the units from to Chapala Basin.

  17. Patterns of biodiversity and endemism on Indo-West Pacific coral reefs

    OpenAIRE

    Reaka, Marjorie L.; Rodgers, Paula J.; Kudla, Alexei U.

    2008-01-01

    Diversity of the primary groups of contemporary Indo-West Pacific coral reef organisms, including mantis shrimps (stomatopod crustaceans), peaks in the Indo-Australian Archipelago (IAA), reaches a lower peak in East Africa and Madagascar [Indian Ocean continental (IOC)], and declines in the central Indian Ocean (IO) and Central Pacific (CP). Percent endemism in stomatopods (highest in the IAA, high in the IOC, lower in regions adjacent to centers, and moderate in the CP) correlates positively...

  18. High continental weathering rate during Early Cambrian: Evidence from Os isotopic composition of Early Cambrian Ocean

    Science.gov (United States)

    Jiang, S.-Y.; Yang, J.-H.; Ling, H.-F.; Feng, H.-Z.; Chen, Y.-Q.; Chen, J.-H.

    2003-04-01

    The paleo-ocean environmental change during the Precambrian-Cambrian transition is a key issue related to the causes for an explosive radiation of different metazoan phyla during Early Cambrian. The chemical and isotopic compositions of marine sediments and chemical precipitates such as carbonates, phosphorites, siliceous rocks, and black shales record the changing composition and physical conditions of the seawater in which these rocks accumulated. Organic carbon-rich black shales from marine environments are commonly enriched in a number of trace elements such as Ni, Mo, V, Co, Cr, Au, U, As, Pb, Zn, Cu, Re, and platinum-group-elements (PGE). Recent researches have demonstrated that Re-Os isotopes and PGE contents in black shales are useful proxies for seawater chemistry. It is believed that Re and Os in orgainc-carbon rich black shales are mostly hydrogeneous in origin which were largely sequestered from seawater at the time of deposition. In South China, the Lower Cambrian black shale sequence of the Niutitang Formation (and lateral equivalents) exists broadly several thousands kilometers. The lowermost sequence of this formation contain a thin sulfide ore horizon with an apparently unique and extreme case of metal enrichments such as Mo, Ni, Se, Re, Os, As, Hg, Sb, Ag, Au, Pt, and Pd. In this study, we conducted a preliminary investigation of Re-Os isotopes and Plantium Group Element (PGE) distribution patterns of the balck shales and intercalated Ni-Mo polymetallic sulfide bed from Guizhou and Hunan Provinces. The high rOs(t) values of the black shales indicate that the Early Cambrian ocean in Yangtze Platform had a highly radiogenic Os, possibly as a result of high continental weathering rate at that time. The Ni-Mo polymetallic sulfide ores within the black shales have lower rOs(t) values than the black shales, and they show similar REE and PGE patterns as the hydrothermal siliceous rocks within the Lower Cambrian strata, which suggest that the Ni

  19. High regional climate sensitivity over continental China constrained by glacial-recent changes in temperature and the hydrological cycle.

    Science.gov (United States)

    Eagle, Robert A; Risi, Camille; Mitchell, Jonathan L; Eiler, John M; Seibt, Ulrike; Neelin, J David; Li, Gaojun; Tripati, Aradhna K

    2013-05-28

    The East Asian monsoon is one of Earth's most significant climatic phenomena, and numerous paleoclimate archives have revealed that it exhibits variations on orbital and suborbital time scales. Quantitative constraints on the climate changes associated with these past variations are limited, yet are needed to constrain sensitivity of the region to changes in greenhouse gas levels. Here, we show central China is a region that experienced a much larger temperature change since the Last Glacial Maximum than typically simulated by climate models. We applied clumped isotope thermometry to carbonates from the central Chinese Loess Plateau to reconstruct temperature and water isotope shifts from the Last Glacial Maximum to present. We find a summertime temperature change of 6-7 °C that is reproduced by climate model simulations presented here. Proxy data reveal evidence for a shift to lighter isotopic composition of meteoric waters in glacial times, which is also captured by our model. Analysis of model outputs suggests that glacial cooling over continental China is significantly amplified by the influence of stationary waves, which, in turn, are enhanced by continental ice sheets. These results not only support high regional climate sensitivity in Central China but highlight the fundamental role of planetary-scale atmospheric dynamics in the sensitivity of regional climates to continental glaciation, changing greenhouse gas levels, and insolation.

  20. Hypo-endemic onchocerciasis hotspots: defining areas of high risk through micro-mapping and environmental delineation

    National Research Council Canada - National Science Library

    Kelly-Hope, Louise A; Unnasch, Thomas R; Stanton, Michelle C; Molyneux, David H

    2015-01-01

    ...) is targeted for elimination in Africa. This is a significant change in strategy from the 'control' of meso- and hyper-endemic areas through mass drug administration (MDA) with Mectizan® (ivermectin...

  1. Hepatitis B virus genotypes from European origin explains the high endemicity found in some areas from southern Brazil.

    Science.gov (United States)

    Bertolini, Dennis Armando; Gomes-Gouvêa, Michele Soares; Guedes de Carvalho-Mello, Isabel Maria Vicente; Carvalho-Mello, Isabel Maria Vicente Guedes de; Saraceni, Cláudia Patara; Sitnik, Roberta; Grazziotin, Felipe Gobbi; Laurino, Jomar Pereira; Laurindo, Jomar Pereira; Fagundes, Nelson Jurandi Rosa; Carrilho, Flair José; Pinho, João Renato Rebello

    2012-08-01

    Southern Brazil is considered an area of low Hepatitis B endemicity, but some areas of higher endemicity have been described in the Southwest of Paraná and Santa Catarina states. The aim of this study was to evaluate viral genotypes circulating throughout Paraná state. PCR amplification and partial sequencing of the S gene was carried out in 228 samples from HBsAg positive candidate blood donors. Samples have been collected in seven different counties (Cascavel, Curitiba, Foz do Iguaçu, Francisco Beltrão, Maringá, Londrina and Paranaguá). The most common HBV genotype in Paraná state was D (82.9%; 189/228), followed by A (14.1%; 32/228). Genotypes F (1.3%; 3/228), C (1.3%; 3/228) and H (0.4%; 1/228) were also found. Distribution of genotypes was different in the studied counties, but genotype D was the most frequent in all of them. In Francisco Beltrão, all studied samples belonged to genotype D. The high prevalence of HBV genotype D in South of Brazil is explained by the intense migration of settlers from Europeans countries. Subgenotypes A1 and A2 were identified circulating in all cities where HBV/A was found. As observed in other areas of Brazil, HBV/A1 is more frequent than the HBV/A2 in Paraná state and its presence was significantly larger in black and mulatto individuals. Genotype C was found only in individuals with Asian ancestry from Londrina and Maringá. Most HBV/F sequences identified in this study were classified as subgenotype F2a that was previously described in Brazil. The sole case of subgenotype F4 was from Foz do Iguaçu city, near to Northern Argentina, where F4 is highly prevalent. The single genotype H sample was from Curitiba. This is the first case of this genotype described in Brazil. Further studies should be carried out to determine if more genotype H samples can be found in other populations from Brazil.

  2. Mode of occurrence of arsenic in high-As coals from endemic arsenosis areas in southwestern Guizhou Province, China

    Institute of Scientific and Technical Information of China (English)

    DING Zhen-hua; ZHENG Bao-shao; ZHUANG Min; HU Tian-dou

    2007-01-01

    The use of high As-bearing coals has caused more than 3,000 cases of arsenosis patients in southwest Guizhou Province, China. The mode of occurrence of arsenic in coal is an important key role in understanding its behavior during usage and damage pathway to human health. Coal samples from endemic arsenosis areas were analyzed with INAA, EMPA, SEM-EDX, LTA, XRD, XAFS, and sequential leaching experiment. Arsenic in pyrite is from under the limit of EMPA to 1.75%, and in most cases, the content of arsenic is lower than 0.5%. Besides pyrite and arsenopyrite, SEM-EDX combined with LTA and XRD find that sulfates, clay and phosphates also contain arsenic. XAFS shows that arsenic mainly exists in the form of As5+. More than 50% of arsenic stayes in residual solid and combined with organic matrix in two samples, but most arsenic is leached out in other samples. The occurrence of such exceptionally high As contents in coal and the fact that the arsenic is dominantly organically associated are unique observations.

  3. Construction of a mathematical model for tuberculosis transmission in highly endemic regions of the Asia-Pacific.

    Science.gov (United States)

    Trauer, James M; Denholm, Justin T; McBryde, Emma S

    2014-10-07

    We present a mathematical model to simulate tuberculosis (TB) transmission in highly endemic regions of the Asia-Pacific, where epidemiology does not appear to be primarily driven by HIV-coinfection. The ten-compartment deterministic model captures many of the observed phenomena important to disease dynamics, including partial and temporary vaccine efficacy, declining risk of active disease following infection, the possibility of reinfection both during the infection latent period and after treatment, multidrug resistant TB (MDR-TB) and de novo resistance during treatment. We found that the model could not be calibrated to the estimated incidence rate without allowing for reinfection during latency, and that even in the presence of a moderate fitness cost and a lower value of R0, MDR-TB becomes the dominant strain at equilibrium. Of the modifiable programmatic parameters, the rate of detection and treatment commencement was the most important determinant of disease rates with each respective strain, while vaccination rates were less important. Improved treatment of drug-susceptible TB did not result in decreased rates of MDR-TB through prevention of de novo resistance, but rather resulted in a modest increase in MDR-TB through strain replacement. This was due to the considerably greater relative contribution of community transmission to MDR-TB incidence, by comparison to de novo amplification of resistance in previously susceptible strains.

  4. Fresh fruits, vegetables and mushrooms as transmission vehicles for Echinococcus multilocularis in highly endemic areas of Poland: reply to concerns.

    Science.gov (United States)

    Lass, Anna; Szostakowska, Beata; Myjak, Przemysław; Korzeniewski, Krzysztof

    2016-09-01

    Echinococcus multilocularis is a tapeworm that may cause alveolar echinococcosis (AE), one of the most dangerous parasitic zoonoses. As in the case of other foodborne diseases, unwashed fruits and vegetables, contaminated with dispersed forms of E. multilocularis, may serve as an important transmission route for this parasite. In this article, we reply to the incorrect interpretation of results of our study concerning the detection of E. multilocularis DNA in fresh fruit, vegetable and mushroom samples collected from the highly endemic areas of the Warmia-Masuria Province, Poland, to dispel any doubts. The accusations formulated by the commentators concerning our paper are unfounded; moreover, these commentators demand information which was beyond the purview of our study. Making generalisations and drawing far-reaching conclusions from our work is also unjustified. The majority of positive samples were found in only a few hyperendemic communities; this information corresponds with the highest number of both infected foxes and AE cases in humans recorded in this area. Our findings indicate that E. multilocularis is present in the environment and may create a potential risk for the inhabitants. These people should simply be informed to wash fruits and vegetables before eating. No additional far-reaching conclusions should be drawn from our data. We believe these commentators needlessly misinterpreted our results and disseminated misleading information. Nevertheless, we would like to encourage any readers simply to contact us if any aspects of our study are unclear.

  5. High-resolution genotyping of the endemic Salmonella Typhi population during a Vi (typhoid vaccination trial in Kolkata.

    Directory of Open Access Journals (Sweden)

    Kathryn E Holt

    2012-01-01

    Full Text Available BACKGROUND: Typhoid fever, caused by Salmonella enterica serovar Typhi (S. Typhi, is a major health problem especially in developing countries. Vaccines against typhoid are commonly used by travelers but less so by residents of endemic areas. METHODOLOGY: We used single nucleotide polymorphism (SNP typing to investigate the population structure of 372 S. Typhi isolated during a typhoid disease burden study and Vi vaccine trial in Kolkata, India. Approximately sixty thousand people were enrolled for fever surveillance for 19 months prior to, and 24 months following, Vi vaccination of one third of the study population (May 2003-December 2006, vaccinations given December 2004. PRINCIPAL FINDINGS: A diverse S. Typhi population was detected, including 21 haplotypes. The most common were of the H58 haplogroup (69%, which included all multidrug resistant isolates (defined as resistance to chloramphenicol, ampicillin and co-trimoxazole. Quinolone resistance was particularly high among H58-G isolates (97% Nalidixic acid resistant, 30% with reduced susceptibility to ciprofloxacin. Multiple typhoid fever episodes were detected in 22 households, however household clustering was not associated with specific S. Typhi haplotypes. CONCLUSIONS: Typhoid fever in Kolkata is caused by a diverse population of S. Typhi, however H58 haplotypes dominate and are associated with multidrug and quinolone resistance. Vi vaccination did not obviously impact on the haplotype population structure of the S. Typhi circulating during the study period.

  6. High Plasmodium malariae Prevalence in an Endemic Area of the Colombian Amazon Region.

    Science.gov (United States)

    Camargo-Ayala, Paola Andrea; Cubides, Juan Ricardo; Niño, Carlos Hernando; Camargo, Milena; Rodríguez-Celis, Carlos Arturo; Quiñones, Teódulo; Sánchez-Suárez, Lizeth; Patarroyo, Manuel Elkin; Patarroyo, Manuel Alfonso

    2016-01-01

    Malaria is a worldwide public health problem; parasites from the genus Plasmodium are the aetiological agent for this disease. The parasites are mostly diagnosed by conventional microscopy-based techniques; however, their limitations have led to under-registering the reported prevalence of Plasmodium species. This study has thus been aimed at evaluating the infection and coinfection prevalence of 3 species of Plasmodium spp., in an area of the Colombian Amazon region. Blood samples were taken from 671 symptomatic patients by skin puncture; a nested PCR amplifying the 18S ssRNA region was used on all samples to determine the presence of P. vivax, P. malariae and P. falciparum. Statistical analysis determined infection and coinfection frequency; the association between infection and different factors was established. The results showed that P. vivax was the species having the greatest frequency in the study population (61.4%), followed by P. malariae (43.8%) and P. falciparum (11.8%). The study revealed that 35.8% of the population had coinfection, the P. vivax/P. malariae combination occurring most frequently (28.3%); factors such as age, geographical origin and clinical manifestations were found to be associated with triple-infection. The prevalence reported in this study differed from previous studies in Colombia; the results suggest that diagnosis using conventional techniques could be giving rise to underestimating some Plasmodium spp. species having high circulation rates in Colombia (particularly in the Colombian Amazon region). The present study's results revealed a high prevalence of P. malariae and mixed infections in the population being studied. The results provide relevant information which should facilitate updating the epidemiological panorama and species' distribution so as to include control, prevention and follow-up measures.

  7. High Plasmodium malariae Prevalence in an Endemic Area of the Colombian Amazon Region

    Science.gov (United States)

    Camargo-Ayala, Paola Andrea; Cubides, Juan Ricardo; Niño, Carlos Hernando; Camargo, Milena; Rodríguez-Celis, Carlos Arturo; Quiñones, Teódulo; Sánchez-Suárez, Lizeth; Patarroyo, Manuel Elkin

    2016-01-01

    Malaria is a worldwide public health problem; parasites from the genus Plasmodium are the aetiological agent for this disease. The parasites are mostly diagnosed by conventional microscopy-based techniques; however, their limitations have led to under-registering the reported prevalence of Plasmodium species. This study has thus been aimed at evaluating the infection and coinfection prevalence of 3 species of Plasmodium spp., in an area of the Colombian Amazon region. Blood samples were taken from 671 symptomatic patients by skin puncture; a nested PCR amplifying the 18S ssRNA region was used on all samples to determine the presence of P. vivax, P. malariae and P. falciparum. Statistical analysis determined infection and coinfection frequency; the association between infection and different factors was established. The results showed that P. vivax was the species having the greatest frequency in the study population (61.4%), followed by P. malariae (43.8%) and P. falciparum (11.8%). The study revealed that 35.8% of the population had coinfection, the P. vivax/P. malariae combination occurring most frequently (28.3%); factors such as age, geographical origin and clinical manifestations were found to be associated with triple-infection. The prevalence reported in this study differed from previous studies in Colombia; the results suggest that diagnosis using conventional techniques could be giving rise to underestimating some Plasmodium spp. species having high circulation rates in Colombia (particularly in the Colombian Amazon region). The present study’s results revealed a high prevalence of P. malariae and mixed infections in the population being studied. The results provide relevant information which should facilitate updating the epidemiological panorama and species’ distribution so as to include control, prevention and follow-up measures. PMID:27467587

  8. First detection of Echinococcus multilocularis in dogs in a highly endemic area of Poland.

    Science.gov (United States)

    Karamon, Jacek; Samorek-Pierog, Malgorzata; Kochanowski, Maciej; Dabrowska, Joanna; Sroka, Jacek; Golab, Elzbieta; Umhang, Gerald; Cencek, Tomasz

    2016-06-02

    The aim of the investigation was to estimate the epizootic situation concerning infection by the cestode Echinococcus multilocularis Leuckart, 1863 in dogs (Canis lupus familiaris Linnaeus) from a Polish region where this parasite is highly prevalent in red foxes. Faecal samples (n = 148) were collected from rural dogs in Podkarpackie Province. Samples were examined through nested PCR (for E. multilocularis), multiplex PCR (E. multilocularis, species of Taenia Linnaeus, 1758) and PCR [E. granulosus (Batsch, 1786)]. Specific products were sequenced. Faeces were also examined coproscopically. In samples from two dogs (1.4%), there were positive PCR results for E. multilocularis. Taenia-specific PCR products were found in nine dogs (6.1%). Sequencing identified Taenia serialis (Gervais, 1847), T. hydatigena Pallas, 1766, T. pisiformis (Bloch, 1780) and Hydatigera taeniaeformis (Batsch, 1786). One sample (0.7%) was identified as Mesocestoides litteratus (Batsch, 1786). All samples were negative for E. granulosus with PCR. Taking into account coproscopic and PCR results, 28% of dogs were infected with helminths (8% with tapeworms). It should be stressed that one of the infected with E. multilocularis dogs shed eggs of the Taenia type and had a habit of preying on rodents. This investigation revealed the presence of E. multilocularis in dogs for the first time in Poland.

  9. Pure neuritic leprosy in patients from a high endemic region of Colombia.

    Science.gov (United States)

    Rodriguez, Gerzain; Pinto, Rafael; Gomez, Yenny; Rengifo, Maria Leonor; Estrada, Olga Lucia; Sarmiento, Marta; Lopez, Fernando; Beltran-Alzate, Juan Camilo; Cardona-Castro, Nora

    2013-03-01

    Agua de Dios was a leprosarium for leprosy patients' obligatory isolation (1872-1961). Its leprosy incidence is the highest in Colombia (1.5-7/10000). Relapses are common. Government grant of US$ 200 per month subsidy is available to patients with disabilities. Spontaneous consultation with neural symptoms is frequent and simulation to get the subsidy has to be considered. We studied 36 subjects (2007-2009), with ages from 29-78, 19 of them men, with neural symptoms of 6 months to 20 years evolution. All had clinical examination, bacteriological examination, skin and nerve biopsies, electromyography (EMG), PCR for M. leprae, IgM anti-PGL1, and lepromin A. All but two are household contacts of leprosy patients. Symptoms were hypoesthesia of the hands and feet, and difficulty using hands with loss of muscular strength. None had skin lesions. Three had thickening of ulnar nerve. Lepromin was positive in all; bacteriology and biopsies were negative in all. The speed and amplitude of neural conduction were altered in 34 patients; two women had normal EMG and were considered to be feigning the disease; 21 were diagnosed as PNL by clinical, epidemiological and EMG findings; five of them had a positive PCR and one, high titers for IgM anti PGL1. Nine other subjects had diabetes and six carpal tunnel syndrome (CTS). Slow progression of disease, the lack of neural enlargement and the neural biopsies without inflammation suggest that most of these patients could have spontaneously cured PNL, as happens with other cases of paucibacillary leprosy. Diabetes and CTS are important differential diagnoses of PNL. Patients were treated with MDT and received the state subsidy.

  10. Architectures of the Moroccan continental shelf of the Alboran Sea: insights from high-resolution bathymetry and seismic data.

    Science.gov (United States)

    Lafosse, Manfred; Gorini, Christian; Leroy, Pascal; d'Acremont, Elia; Rabineau, Marina; Ercilla, Gemma; Alonso, Belén; Ammar, Abdellah

    2016-04-01

    The MARLBORO and the SARAS oceanographic surveys have explored the continental shelf in the vicinity of the transtensive Nekor basin (South Alboran Sea, Western Mediterranean) and over three submarine highs located at several tens of kilometers from the shelf. Those surveys have produced high-resolution (≤29m²/pixel) bathymetry maps. Simultaneously, seismic SPARKER and TOPAS profiles were recorded. To quantify and understand Quaternary vertical motions of this tectonically active area, we searched for morphological and sedimentary paleobathymetric or paleo-elevations markers. Shelf-edge wedges associated marine terraces and paleo-shorelines have been identified on the bathymetry and on seismic cross-sections. These features reflect the trends of long term accommodation variations. Along the Moroccan continental shelf the lateral changes of shelf-edges geometries and the spatial distribution of marine landforms (sedimentary marine terraces, sediment wave fields, marine incisions) reflect the interaction between sea level changes and spatial variations of subsidence rates. Positions of paleo-shorelines identified in the studied area have been correlated with the relative sea-level curve (Rohling et al., 2014). Several still stands or slow stands periods have been recognized between -130-125m, -100-110m and -85-80m. The astronomical forcing controls the architecture of Mediterranean continental shelves. Marine landforms distribution also reveals the way sea level changed since the LGM. The comparison with observations on other western Mediterranean margins (e.g. the Gulf of Lion, the Ionian-Calabrian shelf) allowed a first order access to vertical motion rates.

  11. High resolution melting: a useful field-deployable method to measure dhfr and dhps drug resistance in both highly and lowly endemic Plasmodium populations.

    Science.gov (United States)

    Ndiaye, Yaye Dié; Diédhiou, Cyrille K; Bei, Amy K; Dieye, Baba; Mbaye, Aminata; Mze, Nasserdine Papa; Daniels, Rachel F; Ndiaye, Ibrahima M; Déme, Awa B; Gaye, Amy; Sy, Mouhamad; Ndiaye, Tolla; Badiane, Aida S; Ndiaye, Mouhamadou; Premji, Zul; Wirth, Dyann F; Mboup, Souleymane; Krogstad, Donald; Volkman, Sarah K; Ahouidi, Ambroise D; Ndiaye, Daouda

    2017-04-19

    Emergence and spread of drug resistance to every anti-malarial used to date, creates an urgent need for development of sensitive, specific and field-deployable molecular tools for detection and surveillance of validated drug resistance markers. Such tools would allow early detection of mutations in resistance loci. The aim of this study was to compare common population signatures and drug resistance marker frequencies between two populations with different levels of malaria endemicity and history of anti-malarial drug use: Tanzania and Sénégal. This was accomplished by implementing a high resolution melting assay to study molecular markers of drug resistance as compared to polymerase chain reaction-restriction fragment length polymorphism (PCR/RFLP) methodology. Fifty blood samples were collected each from a lowly malaria endemic site (Sénégal), and a highly malaria endemic site (Tanzania) from patients presenting with uncomplicated Plasmodium falciparum malaria at clinic. Data representing the DHFR were derived using both PCR-RFLP and HRM assay; while genotyping data representing the DHPS were evaluated in Senegal and Tanzania using HRM. Msp genotyping analysis was used to characterize the multiplicity of infection in both countries. A high prevalence of samples harbouring mutant DHFR alleles was observed in both population using both genotyping techniques. HRM was better able to detect mixed alleles compared to PCR/RFLP for DHFR codon 51 in Tanzania; and only HRM was able to detect mixed infections from Senegal. A high prevalence of mutant alleles in DHFR (codons 51, 59, 108) and DHPS (codon 437) were found among samples from Sénégal while no mutations were observed at DHPS codons 540 and 581, from both countries. Overall, the frequency of samples harbouring either a single DHFR mutation (S108N) or double mutation in DHFR (C59R/S108N) was greater in Sénégal compared to Tanzania. Here the results demonstrate that HRM is a rapid, sensitive, and field

  12. Impact of asymptomatic Plasmodium falciparum parasitemia on the imunohematological indices among school children and adolescents in a rural area highly endemic for Malaria in southern Mozambique

    OpenAIRE

    Gudo, Eduardo Samo; Prista, António; Jani, Ilesh V

    2013-01-01

    Background Asymptomatic Plasmodium falciparum parasitemia (APFP) has been reported to be highly prevalent in Sub-Saharan Africa, a region heavily burdened by malaria, yet, the impact of APFP on the immunological reference values have not yet been established. This study was aimed at i) determine the prevalence of APFP in children and adolescents living in a region highly endemic for malaria in southern Mozambique and its impact on the immuno-hematological indices and ii) determine the factors...

  13. Burned and devoured-Introduced herbivores, fire, and the endemic flora of the high-elevation ecosystem on La Palma, Canary Islands

    OpenAIRE

    Irl, Severin D. H.; Steinbauer, Manuel; Messinger, Jana; Blume-Werry, Gesche; Palomares-Martinez, Angel; Beierkuhnlein, Carl; Jentsch, Anke

    2014-01-01

    Novel disturbance regimes (e.g., introduced herbivores and fire) are among the major drivers of degradation in island ecosystems. High-elevation ecosystems (HEEs) on islands might be especially vulnerable to these disturbances due to high endemism. Here, data from an 11-year exclosure experiment in the HEE of La Palma (Canary Islands) are presented where mammalian herbivores have been introduced. We investigate the combined effect of herbivory and fire on total species richness, seedling rich...

  14. High-resolution geophysical data from the inner continental shelf—Buzzards Bay, Massachusetts

    Science.gov (United States)

    Ackerman, Seth D.; Andrews, Brian D.; Foster, David S.; Baldwin, Wayne E.; Schwab, William C.

    2012-01-01

    The U.S. Geological Survey (USGS) and the Massachusetts Office of Coastal Zone Management (CZM) have cooperated to map approximately 410 square kilometers (km²) of the inner continental shelf in Buzzards Bay, Massachusetts. This report contains geophysical data collected by the USGS on three cruises conducted in 2009, 2010, and 2011, and additional bathymetry data collected by the National Oceanic and Atmospheric Administration in 2004. The geophysical data include (1) swath bathymetry using interferometric sonar and multibeam echosounder systems, (2) acoustic backscatter from sidescan sonar, and (3) seismic-reflection profiles from a chirp subbottom profiler. These spatial data support research on the Quaternary evolution of Buzzards Bay, the influence of sea-level change and sediment supply on coastal evolution, and efforts to understand the type, distribution, and quality of subtidal marine habitats in the coastal ocean of Massachusetts.

  15. High-Resolution geophysical data from the inner continental shelf at Vineyard Sound, Massachusetts

    Science.gov (United States)

    Andrews, Brian D.; Ackerman, Seth D.; Baldwin, Wayne E.; Foster, David S.; Schwab, William C.

    2013-01-01

    The U.S. Geological Survey (USGS) and the Massachusetts Office of Coastal Zone Management (CZM) have mapped approximately 340 square kilometers of the inner continental shelf in Vineyard Sound, Massachusetts, under a cooperative mapping program. The geophysical data collected between 2009 and 2011 by the U.S. Geological Survey as part of this program are published in this report. The data include (1) swath bathymetry from interferometric sonar, (2) acoustic backscatter from sidescan sonar, and (3) seismic-reflection profiles from a chirp subbottom profiler. These data were collected to support research on the influence of sea-level change and sediment supply on coastal evolution and sediment transport processes and to provide baseline seabed characterization information required for management of coastal and offshore resources within the coastal zone of Massachusetts.

  16. Neurology of endemic skeletal fluorosis

    Directory of Open Access Journals (Sweden)

    Reddy D

    2009-01-01

    Full Text Available Endemic skeletal fluorosis is widely prevalent in India and is a major public health problem. The first ever report of endemic skeletal fluorosis and neurological manifestation was from Prakasam district in Andhra Pradesh in the year 1937. Epidemiological and experimental studies in the endemic areas suggest the role of temperate climate, hard physical labor, nutritional status, presence of abnormal concentrations of trace elements like strontium, uranium, silica in water supplies, high fluoride levels in foods and presence of kidney disease in the development of skeletal fluorosis. Neurological complications of endemic skeletal fluorosis, namely radiculopathy, myelopathy or both are mechanical in nature and till date the evidence for direct neurotoxicity of fluoride is lacking. Prevention of the disease should be the aim, knowing the pathogenesis of fluorosis. Surgery has a limited role in alleviating the neurological disability and should be tailored to the individual based on the imaging findings.

  17. Detection of high endemic and zoonotic risk areas regarding the infestation with Taenia solium larvae in pigs in Romania

    Directory of Open Access Journals (Sweden)

    Ana Maria Oleleu

    2016-11-01

    Full Text Available In Romania, it is necessary to collect recent data on the prevalence of swine cysticercosis, to detect areas of high endemicity and zoonotic risk, to prevent economic losses through proper implementation of control programs. A retrospective epidemiological study was performed during the period 2009-2013, by accessing report/surveillance systems and management of infected animals by analyzing the temporal and spatial distribution of swine cysticercosis in Romania. The study was conducted on the reporting of cases confirmed after the macroscopic exam in slaughterhouses after slaughtering the animals, in accordance to the national epidemio-surveillance strategic program for swine cysticercosis.In term of spatial spread, outbreaks were discovered in 7 countries (16.66% of the 42 existing in Romania. During the studied period there were a total of 10 disease outbreaks. In term of temporal spread, cases of disease had been recorded every year taken under study. Links between the same different outbreaks, exist in the same year or in successive years, so we can see evolution trend of infection in the north-west of Romania, where there were discovered five of seven outbreaks.Analyzing the maintaining/recurrence of infection in outbreaks, we can mention Alba country, located in the north-west of the country, where the infestation was maintained 4 years (2009, 2010, 2012, 2013. In Cluj, the results obtained were correlated with T. solium infestation in humans by eating pork. The obtained results demonstrated that the control programs currently applied are not sufficient to diminuate and/or eradicate these diseases in Romania. Serological surveillance and molecular diagnostic tests are mandatory to be introduced, besides the slaughterhouse basic exams.

  18. A cross-sectional analysis of traditional medicine use for malaria alongside free antimalarial drugs treatment amongst adults in high-risk malaria endemic provinces of Indonesia

    OpenAIRE

    Suswardany, Dwi Linna; Sibbritt, David W; Supardi, Sudibyo; Pardosi, Jerico F.; Chang, Sungwon; Adams, Jon

    2017-01-01

    Background The level of traditional medicine use, particularly Jamu use, in Indonesia is substantial. Indonesians do not always seek timely treatment for malaria and may seek self-medication via traditional medicine. This paper reports findings from the first focused analyses of traditional medicine use for malaria in Indonesia and the first such analyses worldwide to draw upon a large sample of respondents across high-risk malaria endemic areas. Methods A sub-study of the Indonesia Basic Hea...

  19. Assessing PM2.5 Exposures with High Spatiotemporal Resolution across the Continental United States.

    Science.gov (United States)

    Di, Qian; Kloog, Itai; Koutrakis, Petros; Lyapustin, Alexei; Wang, Yujie; Schwartz, Joel

    2016-05-01

    A number of models have been developed to estimate PM2.5 exposure, including satellite-based aerosol optical depth (AOD) models, land-use regression, or chemical transport model simulation, all with both strengths and weaknesses. Variables like normalized difference vegetation index (NDVI), surface reflectance, absorbing aerosol index, and meteoroidal fields are also informative about PM2.5 concentrations. Our objective is to establish a hybrid model which incorporates multiple approaches and input variables to improve model performance. To account for complex atmospheric mechanisms, we used a neural network for its capacity to model nonlinearity and interactions. We used convolutional layers, which aggregate neighboring information, into a neural network to account for spatial and temporal autocorrelation. We trained the neural network for the continental United States from 2000 to 2012 and tested it with left out monitors. Ten-fold cross-validation revealed a good model performance with a total R(2) of 0.84 on the left out monitors. Regional R(2) could be even higher for the Eastern and Central United States. Model performance was still good at low PM2.5 concentrations. Then, we used the trained neural network to make daily predictions of PM2.5 at 1 km × 1 km grid cells. This model allows epidemiologists to access PM2.5 exposure in both the short-term and the long-term.

  20. Increasing newly diagnosed rate and changing risk factors of HCV in Yanbian Prefecture, a high endemic area in China.

    Directory of Open Access Journals (Sweden)

    Hong-Xin Piao

    Full Text Available BACKGROUND: The newly diagnosed rate of HCV infection is increasing in China. However, the risk factors have not been fully identified. Here, a survey was performed in Yanbian Prefecture, a high-endemic area in China. METHODS: We identified newly diagnosed HCV infection in 2007-2011, using the local National Disease Supervision Information Management System from the Chinese Center for Disease Control and Prevention. We determined the risk factors using a case-control survey by questionnaire. RESULTS: Yanbian Prefecture had a rapid increase in the yearly newly diagnosed rate of HCV infection from 32.6 to 72.1/100.000 from the year 2007 to 2011. People aged 50-64 years had a high HCV infection of 43.4%, but only 0.3% of cases were reported in those aged less than 20 years. Cosmetic treatment, family history, blood transfusion, and dental treatment were independent risk factors for HCV infection. Unexpectedly, cosmetic treatments [odd ratio (OR = 5.15, 95% confidence interval (CI = 2.31-11.48, P = 0.00] and family history (OR = 4.68, 95% CI = 2.67-8.75, P = 0.00 showed a higher risk than the conventional risk factors of blood transfusion (OR = 4.49, 95% CI = 1.95-10.37, P = 0.001 and dental treatment (OR = 2.98, 95% CI = 1.42-6.25, P = 0.00. To further analyze the intrafamilial transmission, we found that spouses of HCV patients had an increased risk for acquiring HCV (OR = 5.75, 95% CI: 1.94-17.07, without significant association between either HCV RNA viral load (P = 0.29 or genotype (P = 0.43. CONCLUSIONS: HCV infection was increased in Yanbian Prefecture. Cosmetic treatment was a higher risk factor than medical procedure. HCV infection had a clear family clustering phenomenon, especially between spouses.

  1. High Levels of IL-10 and CD4+CD25hi+ Treg Cells in Endemic Burkitt's Lymphoma Patients.

    Science.gov (United States)

    Futagbi, Godfred; Gyan, Ben; Nunoo, Harriet; Tetteh, John K A; Welbeck, Jennifer E; Renner, Lorna Awo; Ofori, Michael; Dodoo, Daniel; Edoh, Dominic A; Akanmori, Bartholomew D

    2015-08-04

    The interplay between Epstein-Barr virus infection, malaria, and endemic Burkitt's Lymphoma is not well understood. Reports show diminished EBV-specific Th1 responses in children living in malaria endemic areas and deficiency of EBNA1-specific IFN-γ T cell responses in children with endemic Burkitt's Lymphoma (eBL). This study, therefore, examined some factors involved in the loss of EBNA-1-specific T cell responses in eBL. T-cell subset frequencies, activation, and IFN-γ- or IL-4-specific responses were analyzed by flow-cytometry. Plasma cytokine levels were measured by ELISA. CD4+ and CD8+ cells in age- and sex-matched healthy controls (n = 3) expressed more IFN-γ in response to all immunostimulants than in pediatric endemic BL (eBL) patients (n = 4). In healthy controls, IFN-γ expression was higher than IL-4 expression, whereas in eBL patients the expression of IL-4 by CD4+ cells to EBNA-1 was slightly higher than IFN-γ. Moreover, the blood levels of TNF-α was significantly lower (p = 0.004) while IL-10 was significantly higher (p = 0.038), in eBL patients (n = 21) compared to controls (n = 16). Additionally, the frequency of CD4+CD25hi+ T cells was higher in both age-matched acute uncomplicated malaria (n = 26) and eBL (n = 14) patients compared to healthy controls (n = 19; p = 0.000 and p = 0.027, respectively). The data suggest that reduced Th1 response in eBL might be due to increased levels of IL-10 and T reg cells.

  2. Proteocephalid tapeworms (Cestoda: Onchoproteocephalidea) of loaches (Cobitoidea): Evidence for monophyly and high endemism of parasites in the Far East.

    Science.gov (United States)

    Scholz, Tomáš; de Chambrier, Alain; Shimazu, Takeshi; Ermolenko, Alexey; Waeschenbach, Andrea

    2017-02-01

    apical organ. The existence of two new species in loaches from the Primorsky Region of Russia indicates high endemism of fish parasites in this region. A key to the identification of recognized species from loaches is provided. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. A high resolution melting real time PCR for mapping of filaria infection in domestic cats living in brugian filariosis-endemic areas.

    Science.gov (United States)

    Wongkamchai, Sirichit; Nochote, Hathai; Foongladda, Suporn; Dekumyoy, Paron; Thammapalo, Suvit; Boitano, John J; Choochote, Wej

    2014-03-17

    We present here a real time PCR with high resolution melting (HRM) analysis for determining the prevalence and distribution of filarial species in domestic cats residing in brugian filariosis endemic areas of Narathiwat province, Thailand. Filarial species can be clearly distinguished in a single well using a single pair of primers. Blood samples were taken from a total of 2039 domestic cats living in endemic areas. Microfilariae were detected in 5.7% of the sample, while the overall prevalence of filaria infection by HRM analysis was 6.6%. The filariae species found in the infected cats were Brugia malayi, Dirofilaria immitis, D. repens as well as Acanthocheilonema (Dipetalonema) reconditum. This is the first report of A. reconditum infection from Thailand. The study also observed an overlapping of the distribution areas of animal and human filariae. From a public health perspective, the distribution and prevalence of these nematodes warrant an appropriate drug-based prophylaxis to be administered to cats in the endemic areas to reduce the number of diseased carriers. Furthermore, this molecular approach is more sensitive than microfilariae detection, enables species identification and greatly facilitates the collection of epidemiological data. Thus, the present study may help to bridge human-animal interface by coordinating research outcomes with the control of zoonoses that is vitally important for human and veterinary public health.

  4. Detection of filaria-specific IgG4 antibodies using Brugia Rapid test in individuals from an area highly endemic for Brugia timori.

    Science.gov (United States)

    Supali, T; Rahmah, N; Djuardi, Y; Sartono, E; Rückert, Paul; Fischer, P

    2004-05-01

    The filarial parasite Brugia timori is of great public health importance in some islands of Eastern Indonesia. To establish a simple serological test for the identification and post-treatment monitoring of areas endemic for B. timori, a rapid immunochromatographic dipstick test (Brugia Rapid, BR) was evaluated on microfilaraemic and amicrofilaraemic individuals. This test is based on the detection of anti-filarial IgG4 antibodies that react with a recombinant Brugia malayi antigen (BmR1). In our study area on Alor island the prevalence of microfilaraemia was 26%. With the BR test, 100% of 196 sera from microfilaraemic persons and 76% of 563 sera from amicrofilaraemic persons, either symptomatic or asymptomatic, reacted positive. All 50 control sera from areas non-endemic for lymphatic filariasis gave negative BR test results. This study showed that the BR test can be also used to detect antibodies against B. timori. Due to the high prevalence of IgG4 antibodies as detected by the BR test (81%), no significant correlation with the prevalence of microfilaraemia could be detected within the endemic village. The BR test also shows great promise to be employed as a monitoring tool for B. timori in the framework of the Global Program to Eliminate Lymphatic Filariasis (GPELF).

  5. Seroprevalence and risk factors of human cysticercosis and taeniasis prevalence in a highly endemic area of epilepsy in Bangoua, west Cameroon.

    Science.gov (United States)

    Nkouawa, Agathe; Dschanou, Armel Romeo; Moyou-Somo, Roger; Sako, Yasuhito; Ito, Akira

    2017-01-01

    Cysticercosis caused by the larvae of Taenia solium is a serious and emerging threat to public health in the endemic areas as well as in the non-endemic areas. Neurocysticercosis, an affection of the central nervous system is a leading cause of epilepsy in endemic areas. This study was carried out to investigate human cysticercosis, taeniasis and risk factors, and also their association with epilepsy in Bangoua, west Cameroon where epilepsy is highly prevalent. Out of 384 people investigated, 12 (3.1%) exhibited antibody response against low molecular weight antigens of T. solium by ELISA. Immunoblot revealed that six persons (1.6%) were seropositive with the same antigens. Among 61 epileptic patients, only one was seropositive by immunoblot and the study did not find any statistically significant difference (P>0.05) in seropositivity to T. solium between epileptic persons (1/61, 1.6%) and non-epileptic group (5/323, 1.5%). In addition, cysticercosis was associated with households eating pork meat from pigs slaughtered at home, but not with other factors. The risk factors including pig farming, the consumption of pork meat, vegetables, and non-drinkable water were attenuated by the relatively good hygiene and pig husbandry practices of the population. No egg of Taenia was found in stool by microscopic examination. All data obtained in this study suggested that cysticercosis might not be the principal causative agent of epilepsy in this area.

  6. Colloquium paper: patterns of biodiversity and endemism on Indo-West Pacific coral reefs.

    Science.gov (United States)

    Reaka, Marjorie L; Rodgers, Paula J; Kudla, Alexei U

    2008-08-12

    Diversity of the primary groups of contemporary Indo-West Pacific coral reef organisms, including mantis shrimps (stomatopod crustaceans), peaks in the Indo-Australian Archipelago (IAA), reaches a lower peak in East Africa and Madagascar [Indian Ocean continental (IOC)], and declines in the central Indian Ocean (IO) and Central Pacific (CP). Percent endemism in stomatopods (highest in the IAA, high in the IOC, lower in regions adjacent to centers, and moderate in the CP) correlates positively with species diversity (this varies with scale) and inversely with species body size. Because it constrains reproductive traits and dispersal, body size is a reliable indicator of speciation and extinction potential in reef stomatopods and probably most marine organisms. Assemblages are dominated by small-sized species in the IAA and IOC. Both speciation and extinction likely are high, resulting in especially high endemism (small ranges reflect both originating and disappearing species) in these regions. Rates of speciation exceed extinction, yielding centers of diversity (especially in the IAA). Dispersal slows speciation and extinction in areas adjacent to these centers. Body size declines toward the CP, especially in atoll environments. Here the wheels of speciation and extinction again spin rapidly but in the opposite direction (extinction > speciation), yielding low diversity and moderate endemism. We conclude that life histories, dispersal, and speciation/extinction dynamics are primary agents that mold patterns of diversity and endemism. Historical factors, currents, productivity, and species diversity itself (through ecological interactions) also influence these patterns, in some cases by altering body size.

  7. Patterns of biodiversity and endemism on Indo-West Pacific coral reefs

    Science.gov (United States)

    Reaka, Marjorie L.; Rodgers, Paula J.; Kudla, Alexei U.

    2008-01-01

    Diversity of the primary groups of contemporary Indo-West Pacific coral reef organisms, including mantis shrimps (stomatopod crustaceans), peaks in the Indo-Australian Archipelago (IAA), reaches a lower peak in East Africa and Madagascar [Indian Ocean continental (IOC)], and declines in the central Indian Ocean (IO) and Central Pacific (CP). Percent endemism in stomatopods (highest in the IAA, high in the IOC, lower in regions adjacent to centers, and moderate in the CP) correlates positively with species diversity (this varies with scale) and inversely with species body size. Because it constrains reproductive traits and dispersal, body size is a reliable indicator of speciation and extinction potential in reef stomatopods and probably most marine organisms. Assemblages are dominated by small-sized species in the IAA and IOC. Both speciation and extinction likely are high, resulting in especially high endemism (small ranges reflect both originating and disappearing species) in these regions. Rates of speciation exceed extinction, yielding centers of diversity (especially in the IAA). Dispersal slows speciation and extinction in areas adjacent to these centers. Body size declines toward the CP, especially in atoll environments. Here the wheels of speciation and extinction again spin rapidly but in the opposite direction (extinction > speciation), yielding low diversity and moderate endemism. We conclude that life histories, dispersal, and speciation/extinction dynamics are primary agents that mold patterns of diversity and endemism. Historical factors, currents, productivity, and species diversity itself (through ecological interactions) also influence these patterns, in some cases by altering body size. PMID:18695226

  8. Bathymetric highs in the mid-slope region of the western continental margin of India - Structure and mode of origin

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, D.G.; Paropkari, A.L.; Krishna, K.S.; Chaubey, A.K.; Ajay, K.K.; Kodagali, V.N.

    brought into focus the presence of mantle based volcanic plugs. Their geomorphological and geophysical expressions and structural pattern and associated deep-seated faults led to suggest continental crust. These features are inferred as rifted fragments...

  9. Machine vision approach to auto-generation of high resolution, continental-scale geomorphometric map from DEM

    Science.gov (United States)

    Jasiewicz, J.; Stepinski, T. F.

    2012-04-01

    -generation of GM from this high resolution, continental size raster having 168000x104000 cells took 60 hours on a single processor computer. Future applications of such GM include coupling it with a search tool capable of querying the continental-scale GM in order to identify all instances of a given type of local landscape.

  10. Continental Dynamics in High Tibetan Plateau: Normal Faulting Type Earthquake Activities and Mechanisms

    Institute of Scientific and Technical Information of China (English)

    Xu Jiren; Zhao Zhixin

    2009-01-01

    Various earthquake fault types were analyzed for this study on the crust movement in the high region of the Tibetan plateau by analyzing mechanism solutions and stress fields. The results show that a lot of normal faulting type earthquakes are concentrated in the central High Tibetan plateau. Many of them are nearly perfect normal fault events. The strikes of the fault planes of normal faulting earthquakes are almost in an N-S direction based on the analyses of the Wulff stereonet diagrams of fault plane solutions. It implies that the dislocation slip vectors of the normal faulting type events have quite great components in the E-W direction. The extensions probably are an eastward extensional motion, being mainly a tectonic active regime in the plateau altitudes. The tensional stress in the E-W or NWW-SEE direction predominates earthquake occurrences in the normal event region of the central plateau. The eastward extensional motion in the high Tibetan plateau is attributable to the gravitational collapse of the high plateau and the eastward extrusion of hotter mantle materials beneath the east boundary of the plateau. Extensional motions from the relaxation of the topography and/or gravitational collapse in the high plateau hardly occurred along the N-S direction. The obstruction for the plateau to move eastward is rather weak.

  11. The effect of stratification and topography on high-frequency internal waves in a continental shelf sea

    Science.gov (United States)

    Domina, Anastasiia; Palmer, Matthew; Vlasenko, Vasil; Sharples, Jonathan; Green, Mattias; Stashchuk, Nataliya

    2017-04-01

    Internal gravity waves (IWs) have been recognised as one of the main drivers of climate controlling circulation, sustaining fisheries in shelf seas and CO2-pump system. High frequency IWs are particularly important to internal mixing in the shelf seas, where they contain an enhanced fraction of the available baroclinic energy. The origin, generation mechanism, propagation and spatial distribution of these waves are unfortunately still poorly understood since they are difficult to measure and simulate, and are therefore not represented in the vast majority of ocean and climate models. In this study we aim to increase our understanding of high frequency IWs dynamics in shelf seas through a combination of observational (from moorings and ocean gliders) and modelling methods (MITgcm), and test the hypothesis that "Solitary waves are responsible for driving a large fraction of the vertical diffusivity at the shelf edge and adjacent shelf region". A new high-resolution (50m horizontal) MITgcm configuration is employed to identify the generation and propagation of IWs in a regional shelf sea and subsequently identify internal wave generation hotspots by using calculated Froude number and body force maps. We assess the likely impact of changing seasonal and climate forcing on IWs with a range of different density structures. Our model suggests that under increasing stratification, the IW field becomes more energetic at all frequencies, however the increase in energy is not evenly distributed. While energy in the dominant low frequency IWs increase by 20-40%, energy associated with high frequency waves increases by as much as 90%. These model results are compared to varying stratification scenarios from observations made during 2012 and 2013 to interpret the impact on continental shelf sea IW generation and propagation. We use the results from a turbulence enabled ocean glider to assess the impact that this varying wavefield has on internal mixing, and discuss the

  12. Comparative infectivity of Fasciola hepatica metacercariae from isolates of the main and secondary reservoir animal host species in the Bolivian Altiplano high human endemic region.

    Science.gov (United States)

    Valero, M A; Mas-Coma, S

    2000-01-01

    Fascioliasis due to Fasciola hepatica (Linnaeus, 1758) is an endemic disease on the Northern Bolivian Altiplano, where human prevalences and intensities are the highest known, sheep and cattle are the main reservoir hosts, and pigs and donkeys the secondary ones. Investigations were carried out to study the viability of metacercariae experimentally obtained from eggs shed by naturally infected Altiplanic sheep, cattle, pigs and donkeys. A total of 157 Wistar rats were infected with doses of 5, 10, 20 and 150 metacercariae. Metacercariae aged for different number of weeks were used to analyse the influence of age on their viability. The number of worms successfully developed in each rat was established by dissection. Results obtained show that metacercarial infectivity is dependent upon storage time, being lower when metacercariae are older. The maximum longevity is 31 weeks using doses of 20 metacercariae per rat and 48 weeks with 150 metacercariae per rat, although in the latter case only a very low percentage of worms is recovered. Age-related infectivity of metacercariae from Altiplanic F. hepatica does not significantly differ from that of the liver fluke in lowlands of other countries. Concerning the influence of the isolate according to host species, results indicate that metacercarial viabilities of pig and donkey isolates are similar to the viabilities of metacercariae of sheep and cattle isolates. Thus, pig and donkey have a high transmission potential capacity concerning this aspect. This fact is of great importance for the control of human and animal fascioliasis in this highly endemic zone.

  13. A cross-sectional analysis of traditional medicine use for malaria alongside free antimalarial drugs treatment amongst adults in high-risk malaria endemic provinces of Indonesia.

    Science.gov (United States)

    Suswardany, Dwi Linna; Sibbritt, David W; Supardi, Sudibyo; Pardosi, Jerico F; Chang, Sungwon; Adams, Jon

    2017-01-01

    The level of traditional medicine use, particularly Jamu use, in Indonesia is substantial. Indonesians do not always seek timely treatment for malaria and may seek self-medication via traditional medicine. This paper reports findings from the first focused analyses of traditional medicine use for malaria in Indonesia and the first such analyses worldwide to draw upon a large sample of respondents across high-risk malaria endemic areas. A sub-study of the Indonesia Basic Health Research/Riskesdas Study 2010 focused on 12,226 adults aged 15 years and above residing in high-risk malaria-endemic provinces. Logistic regression was undertaken to determine the significant associations for traditional medicine use for malaria symptoms. Approximately one in five respondents use traditional medicine for malaria symptoms and the vast majority experiencing multiple episodes of malaria use traditional medicine alongside free antimalarial drug treatments. Respondents consuming traditional medicine for general health/common illness purposes every day (odds ratio: 3.75, 95% Confidence Interval: 2.93 4.79), those without a hospital in local vicinity (odds ratio: 1.31, 95% Confidence Interval: 1.10 1.57), and those living in poorer quality housing, were more likely to use traditional medicine for malaria symptoms. A substantial percentage of those with malaria symptoms utilize traditional medicine for treating their malaria symptoms. In order to promote safe and effective malaria treatment, all providing malaria care in Indonesia need to enquire with their patients about possible traditional medicine use.

  14. USGS advances in integrated, high-resolution sea-floor mapping: inner continental shelf to estuaries

    Science.gov (United States)

    Denny, J.F.; Schwab, W.C.; Twichell, D.C.; O'Brien, T.F.; Danforth, W.W.; Foster, D.S.; Bergeron, E.; Worley, C.W.; Irwin, B.J.; Butman, B.; Valentine, P.C.; Baldwin, W.E.; Morton, R.A.; Thieler, E.R.; Nichols, D.R.; Andrews, B.D.

    2007-01-01

    The U.S. Geological Survey (USGS) has been involved in geological mapping of the sea floor for the past thirty years. Early geophysical and acoustic mapping efforts using GLORIA (Geologic LOng Range Inclined ASDIC) a long-range sidescan-sonar system, provided broad-scale imagery of deep waters within the U.S. Exclusive Economic Zone (EEZ). In the early 1990's, research emphasis shifted from deep- to shallow-water environments to address pertinent coastal research and resource management issues. Use of shallow-water, high-resolution geophysical systems has enhanced our understanding of the processes shaping shallow marine environments. However, research within these shallow-water environments continues to present technological challenges.

  15. RUSLE2015: Modelling soil erosion at continental scale using high resolution input layers

    Science.gov (United States)

    Panagos, Panos; Borrelli, Pasquale; Meusburger, Katrin; Poesen, Jean; Ballabio, Cristiano; Lugato, Emanuele; Montanarella, Luca; Alewell, Christine

    2016-04-01

    Soil erosion by water is one of the most widespread forms of soil degradation in the Europe. On the occasion of the 2015 celebration of the International Year of Soils, the European Commission's Joint Research Centre (JRC) published the RUSLE2015, a modified modelling approach for assessing soil erosion in Europe by using the best available input data layers. The objective of the recent assessment performed with RUSLE2015 was to improve our knowledge and understanding of soil erosion by water across the European Union and to accentuate the differences and similarities between different regions and countries beyond national borders and nationally adapted models. RUSLE2015 has maximized the use of available homogeneous, updated, pan-European datasets (LUCAS topsoil, LUCAS survey, GAEC, Eurostat crops, Eurostat Management Practices, REDES, DEM 25m, CORINE, European Soil Database) and have used the best suited approach at European scale for modelling soil erosion. The collaboration of JRC with many scientists around Europe and numerous prominent European universities and institutes resulted in an improved assessment of individual risk factors (rainfall erosivity, soil erodibility, cover-management, topography and support practices) and a final harmonized European soil erosion map at high resolution. The mean soil loss rate in the European Union's erosion-prone lands (agricultural, forests and semi-natural areas) was found to be 2.46 t ha-1 yr-1, resulting in a total soil loss of 970 Mt annually; equal to an area the size of Berlin (assuming a removal of 1 meter). According to the RUSLE2015 model approximately 12.7% of arable lands in the European Union is estimated to suffer from moderate to high erosion(>5 t ha-1 yr-1). This equates to an area of 140,373 km2 which equals to the surface area of Greece (Environmental Science & Policy, 54, 438-447; 2015). Even the mean erosion rate outstrips the mean formation rate (<1.4 tonnes per ha annually). The recent RUSLE2015

  16. Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

    Science.gov (United States)

    Friedlander, Alan M; Ballesteros, Enric; Caselle, Jennifer E; Gaymer, Carlos F; Palma, Alvaro T; Petit, Ignacio; Varas, Eduardo; Muñoz Wilson, Alex; Sala, Enric

    2016-01-01

    The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

  17. Marine Biodiversity in Juan Fernandez and Desventuradas Islands, Chile: Global Endemism Hotspots.

    Directory of Open Access Journals (Sweden)

    Alan M Friedlander

    Full Text Available The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA, in Desventuradas, the laminarian kelp (Eisenia cokeri, which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC, in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

  18. Tsunami Detection by High-Frequency Radar Beyond the Continental Shelf

    Science.gov (United States)

    Grilli, Stéphan T.; Grosdidier, Samuel; Guérin, Charles-Antoine

    2016-12-01

    Where coastal tsunami hazard is governed by near-field sources, such as submarine mass failures or meteo-tsunamis, tsunami propagation times may be too small for a detection based on deep or shallow water buoys. To offer sufficient warning time, it has been proposed to implement early warning systems relying on high-frequency (HF) radar remote sensing, that can provide a dense spatial coverage as far offshore as 200-300 km (e.g., for Diginext Ltd.'s Stradivarius radar). Shore-based HF radars have been used to measure nearshore currents (e.g., CODAR SeaSonde® system; http://www.codar.com/), by inverting the Doppler spectral shifts, these cause on ocean waves at the Bragg frequency. Both modeling work and an analysis of radar data following the Tohoku 2011 tsunami, have shown that, given proper detection algorithms, such radars could be used to detect tsunami-induced currents and issue a warning. However, long wave physics is such that tsunami currents will only rise above noise and background currents (i.e., be at least 10-15 cm/s), and become detectable, in fairly shallow water which would limit the direct detection of tsunami currents by HF radar to nearshore areas, unless there is a very wide shallow shelf. Here, we use numerical simulations of both HF radar remote sensing and tsunami propagation to develop and validate a new type of tsunami detection algorithm that does not have these limitations. To simulate the radar backscattered signal, we develop a numerical model including second-order effects in both wind waves and radar signal, with the wave angular frequency being modulated by a time-varying surface current, combining tsunami and background currents. In each "radar cell", the model represents wind waves with random phases and amplitudes extracted from a specified (wind speed dependent) energy density frequency spectrum, and includes effects of random environmental noise and background current; phases, noise, and background current are extracted from

  19. Highly complex mitochondrial DNA genealogy in an endemic Japanese subterranean breeding brown frog Rana tagoi (Amphibia, Anura, Ranidae).

    Science.gov (United States)

    Eto, Koshiro; Matsui, Masafumi; Sugahara, Takahiro; Tanaka-Ueno, Tomoko

    2012-10-01

    The endemic Japanese frog Rana tagoi is unique among Holarctic brown frogs in that it breeds in small subterranean streams. Using mitochondrial 16S ribosomal RNA and NADH dehydrogenase subunit 1 genes, we investigated genealogical relationships among geographic samples of this species together with its relative R. sakuraii, which is also a unique stream breeder. These two species together form a monophyletic group, within which both are reciprocally paraphyletic. Rana tagoi is divided into two major clades (Clade A and B) that are composed of 14 genetic groups. Rana sakuraii is included in Clade A and split into two genetic groups, one of which forms a clade (Subclade A-2) with sympatric R. tagoi. This species-level paraphyly appears to be caused by incomplete taxonomy, in addition to introgressive hybridization and/or incomplete lineage sorting. Rana tagoi strongly differs from other Japanese anurans in its geographic pattern of genetic differentiation, most probably in relation to its unique reproductive habits. Taxonomically, R. tagoi surely includes many cryptic species.

  20. Ecosystem services - from assessements of estimations to quantitative, validated, high-resolution, continental-scale mapping via airborne LIDAR

    Science.gov (United States)

    Zlinszky, András; Pfeifer, Norbert

    2016-04-01

    service potential" which is the ability of the local ecosystem to deliver various functions (water retention, carbon storage etc.), but can't quantify how much of these are actually used by humans or what the estimated monetary value is. Due to its ability to measure both terrain relief and vegetation structure in high resolution, airborne LIDAR supports direct quantification of the properties of an ecosystem that lead to it delivering a given service (such as biomass, water retention, micro-climate regulation or habitat diversity). In addition, its high resolution allows direct calibration with field measurements: routine harvesting-based ecological measurements, local biodiversity indicator surveys or microclimate recordings all take place at the human scale and can be directly linked to the local value of LIDAR-based indicators at meter resolution. Therefore, if some field measurements with standard ecological methods are performed on site, the accuracy of LIDAR-based ecosystem service indicators can be rigorously validated. With this conceptual and technical approach high resolution ecosystem service assessments can be made with well established credibility. These would consolidate the concept of ecosystem services and support both scientific research and evidence-based environmental policy at local and - as data coverage is continually increasing - continental scale.

  1. Evidence of a Neoproterozoic active continental margin - Geochemistry and isotope geology of high-grade paragneiss from the Ribeira Orogen, SE Brazil

    Science.gov (United States)

    Capistrano, G. G.; Schmitt, R. S.; Medeiros, S. R.; Fernandes, G. L. F.

    2017-08-01

    Ediacaran paragneisses from the Palmital Unit are located in a key region, between two major tectonic domains of the Ribeira Orogen (in Rio de Janeiro, SE Brazil): the Cabo Frio Tectonic Domain and the Oriental Terrane. We present here petrographic, geochemical and isotopic data in order to partially unravel the origin and tectonic nature of the protoliths from these metamorphic rocks. Litharenites interpreted as immature sediments, mostly derived from the erosion of felsic rocks (granites/rhyolites and diorites/andesites) are here described. Multi-elements patterns and trace elements ratios reinforce an upper continental crust nature for the composition of the protoliths. These were probably located close to the source area and accommodated in semi-arid climate and high topography conditions. Tectonic discrimination diagrams indicate that the Palmital basin developed in an active continental margin, corroborated by the zircon detrital spectra. The main population of detrital zircon (ca. 750-550 Ma) is partially coeval with the age of the Rio Negro continental magmatic arc, resident in the Oriental Terrane. The Palmital basin could represent a forearc environment with no oceanic crust material, but only a continuous sedimentation of turbidites derived from the arc, with gradational bedding signifying a subaqueous environment, without outside tectonic disturbances. On the other hand, TDM ages of 1.6-1.8 Ga suggest that these sediments are not juvenile, indicating also a contribution from an ancient crust. This recycled continental crust could come either from the basement of the Oriental Terrane (which was not identified yet) or from the basement of the Cabo Frio Tectonic Domain. In the last assumption the Palmital deposition would be concomitant with the initiation of continental collision and the subduction of the passive margin of the Cabo Frio Tectonic Domain towards west. This unit was subsequently metamorphosed/deformed during the ca. 540 Ma collision between

  2. Genetic diversity and genetic structure of an endemic Mexican Dusky Rattlesnake (Crotalus triseriatus) in a highly modified agricultural landscape: implications for conservation.

    Science.gov (United States)

    Sunny, Armando; Monroy-Vilchis, Octavio; Zarco-González, Martha M; Mendoza-Martínez, Germán David; Martínez-Gómez, Daniel

    2015-12-01

    It is necessary to determine genetic diversity of fragmented populations in highly modified landscapes to understand how populations respond to land-use change. This information will help guide future conservation and management strategies. We conducted a population genetic study on an endemic Mexican Dusky Rattlesnake (Crotalus triseriatus) in a highly modified landscape near the Toluca metropolitan area, in order to provide crucial information for the conservation of this species. There was medium levels of genetic diversity, with a few alleles and genotypes. We identified three genetically differentiated clusters, likely as a result of different habitat cover type. We also found evidence of an ancestral genetic bottleneck and medium values of effective population size. Inbreeding coefficients were low and there was a moderate gene flow. Our results can be used as a basis for future research and C. triseriatus conservation efforts, particularly considering that the Trans-Mexican Volcanic Belt is heavily impacted by destructive land-use practices.

  3. High similarity of Trypanosoma cruzi kDNA genetic profiles detected by LSSP-PCR within family groups in an endemic area of Chagas disease in Brazil

    Directory of Open Access Journals (Sweden)

    Sandra Maria Alkmim-Oliveira

    2014-10-01

    Full Text Available Introduction Determining the genetic similarities among Trypanosoma cruzi populations isolated from different hosts and vectors is very important to clarify the epidemiology of Chagas disease. Methods An epidemiological study was conducted in a Brazilian endemic area for Chagas disease, including 76 chronic chagasic individuals (96.1% with an indeterminate form; 46.1% with positive hemoculture. Results T. cruzi I (TcI was isolated from one child and TcII was found in the remaining (97.1% subjects. Low-stringency single-specific-primer-polymerase chain reaction (LSSP-PCR showed high heterogeneity among TcII populations (46% of shared bands; however, high similarities (80-100% among pairs of mothers/children, siblings, or cousins were detected. Conclusions LSSP-PCR showed potential for identifying similar parasite populations among individuals with close kinship in epidemiological studies of Chagas disease.

  4. Multilocus phylogenetic analysis of true morels (Morchella) reveals high levels of endemics in Turkey relative to other regions of Europe.

    Science.gov (United States)

    Taskin, Hatira; Büyükalaca, Saadet; Hansen, Karen; O'Donnell, Kerry

    2012-01-01

    The present study was conducted to better understand how the phylogenetic diversity of true morels (Morchella) in Turkey compares with species found in other regions of the world. The current research builds on our recently published surveys of 10 Turkish provinces and the northern hemisphere in which DNA sequence data from 247 and 562 collections respectively were analyzed phylogenetically. Herein we report on phylogenetic analyses of 243 additional collections made in spring 2009 and 2010 from eight additional provinces in the Aegean, Black Sea, central Anatolia, eastern Anatolia and Marmara regions of Turkey. Our analysis revealed that five species within the Esculenta clade (yellow morels) and 15 species within the Elata clade (black morels) were present in Turkey. Our preliminary results also indicate that M. anatolica, recently described from a collection in Muğla province in the Aegean region of Turkey, is a closely related sister of M. rufobrunnea; these two species comprise a separate evolutionary lineage from the Esculenta and Elata clades. Nine species of Morchella currently are known only from Turkey, four species were present in Turkey and other European countries and seven species might have been introduced to Turkey anthropogenically. Three of the putatively exotic species in Turkey appear to be endemic to western North America; they are nested within a clade of fire-adapted morels that dates to the late Oligocene, 25 000 000 y ago. Our results indicate that there are roughly twice as many Morchella species in Turkey compared with the other regions of Europe sampled. Knowledge of Morchella species diversity and their biogeographic distribution are crucial for formulating informed conservation policies directed at preventing species loss and ensuring that annual morel harvests are sustainable and ecologically sound.

  5. Neglected and endemic zoonoses

    OpenAIRE

    2009-01-01

    Endemic zoonoses are found throughout the developing world, wherever people live in close proximity to their animals, affecting not only the health of poor people but often also their livelihoods through the health of their livestock. Unlike newly emerging zoonoses that attract the attention of the developed world, these endemic zoonoses are by comparison neglected. This is, in part, a consequence of under-reporting, resulting in underestimation of their global burden, which in turn artificia...

  6. Differential expression of viral agents in lymphoma tissues of patients with ABC diffuse large B-cell lymphoma from high and low endemic infectious disease regions.

    Science.gov (United States)

    Högfeldt, Therese; Jaing, Crystal; Loughlin, Kevin Mc; Thissen, James; Gardner, Shea; Bahnassy, Abeer A; Gharizadeh, Baback; Lundahl, Joachim; Österborg, Anders; Porwit, Anna; Zekri, Abdel-Rahman N; Khaled, Hussein M; Mellstedt, Håkan; Moshfegh, Ali

    2016-10-01

    Diffuse large B-cell lymphoma (DLBCL), the most common type of non-Hodgkin's lymphoma (NHL) in adults, accounts for approximately 30-40% of newly diagnosed lymphomas worldwide. Environmental factors, such as viruses and bacteria, may contribute to cancer development through chronic inflammation and the integration of oncogenes, and have previously been indicated in cervical cancer, hepatocellular carcinoma, gastric cancer and lymphoproliferative disorders. In the present study, the presence of microbial agents was analyzed in the lymphoma tissue of patients with activated B-cell like (ABC) DLBCL. The present study compared two groups of patients from geographically varied regions that possess a difference in the prevalence of viral and other microbial agents. The patient populations were from Sweden (a low endemic infectious disease region) and Egypt (a high endemic infectious disease region). A differential expression of several viruses in lymphoma tissues was noted when comparing Swedish and Egyptian patients. JC polyomavirus (JCV) was detected in Swedish and Egyptian patients and, uniquely, the complete hepatitis B virus (HBV) genome was detected only in Egyptian lymphoma patients. None of these viruses were detected in control lymph tissues from Sweden or Egypt. In total, 38% of the Egyptian patients were found to have HBV surface antigens (HBsAgs) in their serum; however, HBsAgs were not found in any of the Swedish patients. The percentage of serum HBsAgs in Egyptian patients with ABC DLBCL was significantly increased compared with the general Egyptian population (P<0.05). The present study may support a notion that viral agents, including JCV and HBV, may be involved in the tumorigenesis of DLBCL in regions of high infectious disease.

  7. A cross-sectional analysis of traditional medicine use for malaria alongside free antimalarial drugs treatment amongst adults in high-risk malaria endemic provinces of Indonesia

    Science.gov (United States)

    Suswardany, Dwi Linna; Sibbritt, David W.; Supardi, Sudibyo; Pardosi, Jerico F.; Chang, Sungwon; Adams, Jon

    2017-01-01

    Background The level of traditional medicine use, particularly Jamu use, in Indonesia is substantial. Indonesians do not always seek timely treatment for malaria and may seek self-medication via traditional medicine. This paper reports findings from the first focused analyses of traditional medicine use for malaria in Indonesia and the first such analyses worldwide to draw upon a large sample of respondents across high-risk malaria endemic areas. Methods A sub-study of the Indonesia Basic Health Research/Riskesdas Study 2010 focused on 12,226 adults aged 15 years and above residing in high-risk malaria-endemic provinces. Logistic regression was undertaken to determine the significant associations for traditional medicine use for malaria symptoms. Findings Approximately one in five respondents use traditional medicine for malaria symptoms and the vast majority experiencing multiple episodes of malaria use traditional medicine alongside free antimalarial drug treatments. Respondents consuming traditional medicine for general health/common illness purposes every day (odds ratio: 3.75, 95% Confidence Interval: 2.93 4.79), those without a hospital in local vicinity (odds ratio: 1.31, 95% Confidence Interval: 1.10 1.57), and those living in poorer quality housing, were more likely to use traditional medicine for malaria symptoms. Conclusion A substantial percentage of those with malaria symptoms utilize traditional medicine for treating their malaria symptoms. In order to promote safe and effective malaria treatment, all providing malaria care in Indonesia need to enquire with their patients about possible traditional medicine use. PMID:28329019

  8. Comparison of Microscopy, Nested-PCR, and Real-Time-PCR Assays Using High-Throughput Screening of Pooled Samples for Diagnosis of Malaria in Asymptomatic Carriers from Areas of Endemicity in Myanmar

    Science.gov (United States)

    Wang, Bo; Han, Soe-Soe; Cho, Cho; Han, Jin-Hee; Cheng, Yang; Lee, Seong-Kyun; Galappaththy, Gawrie N. L; Thimasarn, Krongthong; Soe, Myat Thu; Oo, Htet Wai; Kyaw, Myat Phone

    2014-01-01

    Asymptomatic infection is an important obstacle for controlling disease in countries where malaria is endemic. Because asymptomatic carriers do not seek treatment for their infections, they can have high levels of gametocytes and constitute a reservoir available for new infection. We employed a sample pooling/PCR-based molecular detection strategy for screening malaria infection in residents from areas of Myanmar where malaria is endemic. Blood samples (n = 1,552) were collected from residents in three areas of malaria endemicity (Kayin State, Bago, and Tanintharyi regions) of Myanmar. Two nested PCR and real-time PCR assays showed that asymptomatic infection was detected in about 1.0% to 9.4% of residents from the surveyed areas. The sensitivities of the two nested PCR and real-time PCR techniques were higher than that of microscopy examination (sensitivity, 100% versus 26.4%; kappa values, 0.2 to 0.5). Among the three regions, parasite-positive samples were highly detected in subjects from the Bago and Tanintharyi regions. Active surveillance of residents from regions of intense malaria transmission would reduce the risk of morbidity and mitigate transmission to the population in these areas of endemicity. Our data demonstrate that PCR-based molecular techniques are more efficient than microscopy for nationwide surveillance of malaria in countries where malaria is endemic. PMID:24648557

  9. Genetic variation (AFLPs and nuclear microsatellites) in two anagenetically derived endemic species of Myrceugenia (Myrtaceae) on the Juan Fernández Islands, Chile.

    Science.gov (United States)

    López-Sepúlveda, Patricio; Takayama, Koji; Greimler, Josef; Peñailillo, Patricio; Crawford, Daniel J; Baeza, Marcelo; Ruiz, Eduardo; Kohl, Gudrun; Tremetsberger, Karin; Gatica, Alejandro; Letelier, Luis; Novoa, Patricio; Novak, Johannes; Stuessy, Tod F

    2013-04-01

    Anagenesis (or phyletic evolution) is one mode of speciation that occurs in the evolution of plants on oceanic islands. Of two endemic species on the Juan Fernández Islands (Chile), Myrceugenia fernandeziana and M. schulzei (Myrtaceae), believed to have originated anagenetically from different continental progenitors, the first is endemic to Robinson Crusoe Island and has no clear tie to continental relatives; the last is endemic to the younger island, Alejandro Selkirk Island, and has close affinity to M. colchaguensis in mainland Chile. Using AFLPs and six nuclear microsatellites from 381 individuals representing 33 populations, we determined patterns of genetic variation within and among populations on both islands and between those of the islands and mainland. Considerable genetic variation was found within populations on both islands. The level of gene diversity within M. schulzei was equivalent to that of its close continental relative M. colchaguensis. Genetic diversity was not partitioned geographically in M. fernandeziana and was weakly so and nonsignificantly in M. schulzei. The high genetic variation in both taxa is most likely due to anagenetic speciation. Subsidence of the older island Robinson Crusoe, landscape erosion, and restructuring of communities have severely reduced the overall island population to a single panmictic system. On the younger and less modified Alejandro Selkirk Island, slightly stronger patterns of genetic divergence are seen in M. schulzei. Because both species are genetically diverse and number in the thousands of individuals, neither is presently endangered in the archipelago.

  10. Continental Subduction and Subduction Initiation Leading to Extensional Exhumation of Ultra-High Pressure Rocks During Ongoing Plate Convergence in Papua New Guinea

    Science.gov (United States)

    Buck, W. R.; Petersen, K. D.

    2014-12-01

    Subduction of continental rocks is necessary to produce ultra-high pressure (UHP) rocks but the mechanism bringing them to the surface is disputed. A major question is whether this involves fairly small diapirs of crust that move up through the mantle or it involves an entire subducted plate that undergoes coherent 'reverse subduction' (sometimes called 'eduction'). Both mechanisms have been invoked to explain the only known region of on-going exhumation of UHP rocks, on the D'Entrecasteaux Islands of Papua New Guinea. Ductile flow fabrics in the island rocks have been used to argue for a diapiric model while constraints on the plate kinematics of the region require relatively large (>100 km) amounts of recent (>6 Myr) extension, supporting eduction as a primary mechanism. A self-consistent thermo-mechanical model of continental subduction shows that eduction can be accompanied by some ductile flow within the crust. Also we show, that subduction and stacking of continental crust can cause a subduction zone to lock up and lead to subduction initiation elsewhere. When this happens the region of earlier continental subduction can reverse direction causing exhumation of rocks from depth of ~100 km followed by localized extension and plate spreading. This can occur even if a region is in overall convergence. Applied to New Guinea our results are consistent with earlier suggestions that extension of the Woodlark Basin was caused by the initiation of the New Britain Trench, as indicated on the attached figure. We suggest that this subduction initiation event triggered eduction that led to exposure of the D'Entrcasteaux Islands and exhumation of the UHP rocks there. Our numerical results are broadly consistent with the recently refined seismic structure of the region around the islands. The model implies that the present-day basement of the ~70 km wide Goodenough Bay, south of the islands, was subducted then exhumed. This can be tested by drilling.

  11. Neglected and endemic zoonoses.

    Science.gov (United States)

    Maudlin, Ian; Eisler, Mark Charles; Welburn, Susan Christina

    2009-09-27

    Endemic zoonoses are found throughout the developing world, wherever people live in close proximity to their animals, affecting not only the health of poor people but often also their livelihoods through the health of their livestock. Unlike newly emerging zoonoses that attract the attention of the developed world, these endemic zoonoses are by comparison neglected. This is, in part, a consequence of under-reporting, resulting in underestimation of their global burden, which in turn artificially downgrades their importance in the eyes of administrators and funding agencies. The development of cheap and effective vaccines is no guarantee that these endemic diseases will be eliminated in the near future. However, simply increasing awareness about their causes and how they may be prevented-often with very simple technologies-could reduce the incidence of many endemic zoonoses. Sustainable control of zoonoses is reliant on surveillance, but, as with other public-sector animal health services, this is rarely implemented in the developing world, not least because of the lack of sufficiently cheap diagnostics. Public-private partnerships have already provided advocacy for human disease control and could be equally effective in addressing endemic zoonoses.

  12. High seroprevalence of Rift Valley FEVER AND EVIDENCE FOR ENDEMIC circulation in Mbeya region, Tanzania, in a cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Norbert Heinrich

    Full Text Available BACKGROUND: The Rift Valley fever virus (RVFV is an arthropod-borne phlebovirus. RVFV mostly causes outbreaks among domestic ruminants with a major economic impact. Human infections are associated with these events, with a fatality rate of 0.5-2%. Since the virus is able to use many mosquito species of temperate climates as vectors, it has a high potential to spread to outside Africa. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a stratified, cross-sectional sero-prevalence survey in 1228 participants from Mbeya region, southwestern Tanzania. Samples were selected from 17,872 persons who took part in a cohort study in 2007 and 2008. RVFV IgG status was determined by indirect immunofluorescence. Possible risk factors were analyzed using uni- and multi-variable Poisson regression models. We found a unique local maximum of RVFV IgG prevalence of 29.3% in a study site close to Lake Malawi (N = 150. The overall seroprevalence was 5.2%. Seropositivity was significantly associated with higher age, lower socio-economic status, ownership of cattle and decreased with distance to Lake Malawi. A high vegetation density, higher minimum and lower maximum temperatures were found to be associated with RVFV IgG positivity. Altitude of residence, especially on a small scale in the high-prevalence area was strongly correlated (PR 0.87 per meter, 95% CI = 0.80-0.94. Abundant surface water collections are present in the lower areas of the high-prevalence site. RVF has not been diagnosed clinically, nor an outbreak detected in the high-prevalence area. CONCLUSIONS: RVFV is probably circulating endemically in the region. The presence of cattle, dense vegetation and temperate conditions favour mosquito propagation and virus replication in the vector and seem to play major roles in virus transmission and circulation. The environmental risk-factors that we identified could serve to more exactly determine areas at risk for RVFV endemicity.

  13. Highly diverse, poorly studied and uniquely threatened by climate change: an assessment of marine biodiversity on South Georgia's continental shelf.

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    Oliver T Hogg

    Full Text Available We attempt to quantify how significant the polar archipelago of South Georgia is as a source of regional and global marine biodiversity. We evaluate numbers of rare, endemic and range-edge species and how the faunal structure of South Georgia may respond to some of the fastest warming waters on the planet. Biodiversity data was collated from a comprehensive review of reports, papers and databases, collectively representing over 125 years of polar exploration. Classification of each specimen was recorded to species level and fully geo-referenced by depth, latitude and longitude. This information was integrated with physical data layers (e.g. temperature, salinity and flow providing a visualisation of South Georgia's biogeography across spatial, temporal and taxonomic scales, placing it in the wider context of the Southern Hemisphere. This study marks the first attempt to map the biogeography of an archipelago south of the Polar Front. Through it we identify the South Georgian shelf as the most speciose region of the Southern Ocean recorded to date. Marine biodiversity was recorded as rich across taxonomic levels with 17,732 records yielding 1,445 species from 436 families, 51 classes and 22 phyla. Most species recorded were rare, with 35% recorded only once and 86% recorded <10 times. Its marine fauna is marked by the cumulative dominance of endemic and range-edge species, potentially at their thermal tolerance limits. Consequently, our data suggests the ecological implications of environmental change to the South Georgian marine ecosystem could be severe. If sea temperatures continue to rise, we suggest that changes will include depth profile shifts of some fauna towards cooler Antarctic Winter Water (90-150 m, the loss of some range-edge species from regional waters, and the wholesale extinction at a global scale of some of South Georgia's endemic species.

  14. Highly diverse, poorly studied and uniquely threatened by climate change: an assessment of marine biodiversity on South Georgia's continental shelf.

    Science.gov (United States)

    Hogg, Oliver T; Barnes, David K A; Griffiths, Huw J

    2011-01-01

    We attempt to quantify how significant the polar archipelago of South Georgia is as a source of regional and global marine biodiversity. We evaluate numbers of rare, endemic and range-edge species and how the faunal structure of South Georgia may respond to some of the fastest warming waters on the planet. Biodiversity data was collated from a comprehensive review of reports, papers and databases, collectively representing over 125 years of polar exploration. Classification of each specimen was recorded to species level and fully geo-referenced by depth, latitude and longitude. This information was integrated with physical data layers (e.g. temperature, salinity and flow) providing a visualisation of South Georgia's biogeography across spatial, temporal and taxonomic scales, placing it in the wider context of the Southern Hemisphere. This study marks the first attempt to map the biogeography of an archipelago south of the Polar Front. Through it we identify the South Georgian shelf as the most speciose region of the Southern Ocean recorded to date. Marine biodiversity was recorded as rich across taxonomic levels with 17,732 records yielding 1,445 species from 436 families, 51 classes and 22 phyla. Most species recorded were rare, with 35% recorded only once and 86% recorded <10 times. Its marine fauna is marked by the cumulative dominance of endemic and range-edge species, potentially at their thermal tolerance limits. Consequently, our data suggests the ecological implications of environmental change to the South Georgian marine ecosystem could be severe. If sea temperatures continue to rise, we suggest that changes will include depth profile shifts of some fauna towards cooler Antarctic Winter Water (90-150 m), the loss of some range-edge species from regional waters, and the wholesale extinction at a global scale of some of South Georgia's endemic species.

  15. Palaeoproterozoic high-pressure granulite overprint of the Archaean continental crust: evidence for homogeneous crustal thickening (Man Rise, Ivory Coast)

    Science.gov (United States)

    Pitra, Pavel; Kouamelan, Alain N.; Ballèvre, Michel; Peucat, Jean-Jacques

    2010-05-01

    well as coeval intrusion of juvenile magmas. Crustal shortening was mainly accommodated by transpressive shear zones and by lateral crustal spreading rather than large-scale thrust systems. The occurrence of high-pressure granulites does not imply thrust-dominated tectonics. Feybesse, J.-L. & Milési, J.-P., 1994. The Archean/Proterozoic contact zone in West Africa: a mountain belt of décollement thrusting and folding on a continental margin related to 2.1 Ga convergence of Archean cratons? Precambrian Research, 69, 199-227. Schulmann, K., Schaltegger, U., Ježek, J., et al. 2002. Rapid burial and exhumation during orogeny: thickening and synconvergent exhumation of thermally weakened and thinned crust (Variscan orogen in Western Europe). American Journal of Science, 302, 856-879. Schulmann, K., Lexa, O., Štípská, P. et al., 2008. Vertical extrusion and horizontal channel flow of orogenic lower crust: key exhumation mechanisms in large hot orogens? Journal of Metamorphic Geology, 26(2), 273-297.

  16. Continental Divide Trail

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This shapefile was created to show the proximity of the Continental Divide to the Continental Divide National Scenic Trail in New Mexico. This work was done as part...

  17. High diversity and endemism in the genus Cautires Waterhouse, 1879 (Coleoptera: Lycidae from the Malay mountain forests, with the descriptions of fourteen new species

    Directory of Open Access Journals (Sweden)

    Alice Jiruskova

    2016-08-01

    Full Text Available We identified a high diversity in the net-winged beetles of the genus Cautires in Peninsular Malaysia. Fourteen new species are described: Cautires alexae sp. nov., C. andujari sp. nov., C. arribasae sp. nov., C. berembanensis sp. nov., C. campestris sp. nov., C. communis sp. nov., C. jasarensis sp. nov., C. katarinae sp. nov., C. kirstenae sp. nov., C. kotatinggensis sp. nov., C. linardi sp. nov., C. maseki sp. nov., C. pahangensis sp. nov. and C. renatae sp. nov. Seven previously described species are discussed, illustrated and differential diagnoses provided; all species are keyed. The Cautires species differ in a limited number of diagnostic characters, namely in the shape of male antennae, the relative size of eyes and in the shape of the male genitalia. The females are difficult to assign to a conspecific male due to high intraspecific variability. The characteristically low dispersal propensity of net-winged beetles lead to the evolution of the unique fauna in the Malay mountains and despite an extensive study of the type material we recorded only a single species of Cautires occurring simultaneously in Sumatra. We suggest that the Malay mountain fauna is highly endemic and evolved in situ.

  18. Geological and geochemical characteristics of high arsenic coals from endemic arsenosis areas in southwestern Guizhou Province, China

    Science.gov (United States)

    Ding, Z.; Zheng, B.; Long, J.; Belkin, H.E.; Finkelman, R.B.; Chen, C.; Zhou, D.; Zhou, Y.

    2001-01-01

    Southwest Guizhou Province is one of the most important areas of disseminated, sediment-hosted-type Au deposits in China and is an important area of coal production. The chemistry of most of the coals in SW Guizhou is similar to those in other parts of China. Their As content is near the Chinese coal average, but some local, small coal mines contain high As coals. The highest As content is up to 3.5 wt.% in the coal. The use of high As coals has caused in excess of 3000 cases of As poisoning in several villages. The high As coals are in the Longtan formation, which is an alternating marine facies and terrestrial facies. The coals are distributed on both sides of faults that parallel the regional anticlinal axis. The As content of coal is higher closer to the fault plane. The As content of coal changes greatly in different coal beds and different locations of the same bed. Geological structures such as anticlines, faults and sedimentary strata control the distribution of high As coals. Small Au deposits as well as Sb, Hg, and Th mineralization, are found near the high As coals. Although some As-bearing minerals such as pyrite, arsenopyrite, realgar (?), As-bearing sulfate, As-bearing clays, and phosphate are found in the high As coals, their contents cannot account for the abundance of As in some coals. Analysis of the coal indicates that As mainly exists in the form of As5+ and As3+, perhaps, combined with organic compounds. The occurrence of such exceptionally high As contents in coal and the fact that the As is dominantly organically associated are unique observations. ?? 201 Elsevier Science Ltd.

  19. Niche shifts and range expansions along cordilleras drove diversification in a high-elevation endemic plant genus in the tropical Andes.

    Science.gov (United States)

    Kolář, Filip; Dušková, Eva; Sklenář, Petr

    2016-09-01

    The tropical Andes represent one of the world's biodiversity hot spots, but the evolutionary drivers generating their striking species diversity still remain poorly understood. In the treeless high-elevation Andean environments, Pleistocene glacial oscillations and niche differentiation are frequently hypothesized diversification mechanisms; however, sufficiently densely sampled population genetic data supporting this are still lacking. Here, we reconstruct the evolutionary history of Loricaria (Asteraceae), a plant genus endemic to the Andean treeless alpine zone, based on comprehensive population-level sampling of 289 individuals from 67 populations across the entire distribution ranges of its northern Andean species. Partly incongruent AFLP and plastid DNA markers reveal that the distinct genetic structure was shaped by a complex interplay of biogeography (spread along and across the cordilleras), history (Pleistocene glacial oscillations) and local ecological conditions. While plastid variation documents an early split or colonization of the northern Andes by at least two lineages, one of which further diversified, a major split in the AFLP data correlate with altitudinal ecological differentiation. This suggests that niche shifts may be important drivers of Andean diversification not only in forest-alpine transitions, but also within the treeless alpine zone itself. The patterns of genetic differentiation at the intraspecific level reject the hypothesized separation in spatially isolated cordilleras and instead suggest extensive gene flow among populations from distinct mountain chains. Our study highlights that leveraging highly variable markers against extensive population-level sampling is a promising approach to address mechanisms of rapid species diversifications.

  20. Endemic arsenosis caused by indoor combustion of high-As coal in Guizhou Province, P.R. China

    Science.gov (United States)

    Baoshan, Z.; Binbin, W.; Zhenhua, D.; Daixing, Z.; Yunshu, Z.; Chen, Z.; Chaochang, C.; Finkelman, R.B.

    2005-01-01

    The arsenic (As) content of coal relating with mineralization of gold in Southwest Guizhou Province, China is up to 35,000 ppm. The coal is burned indoors in open pits for daily cooking and crop drying. As a result, arsenic is precipitated and concentrated in corn (5-20 ppm), chili (100-800 ppm) and other foods. Arsenic concentrations in the drinking water of high-As coal areas are lower than 50 ppb. The estimated main sources of As exposure in this area are from polluted food. Approximately, 3000 arsenosis patients were found by 1998, and more than 100,000 people from six counties were under the threat in China. This paper presents the major ingestion pathway of this type arsenosis and relative geochemistry of high-As coal. ?? Springer 2005.

  1. High level of genetic differentiation for allelic richness among populations of the argan tree [Argania spinosa (L.) Skeels] endemic to Morocco.

    Science.gov (United States)

    El Mousadik, A; Petit, R J

    1996-05-01

    Genetic diversity at nine isozyme loci was surveyed in an endangered tree species, the argan tree, endemic to south-western Morocco. The species is highly diverse (3.6 alleles/locus) with populations strongly differentiated from each other (F ST=0.25). This example is used to illustrate a method for standardizing measures of allelic richness in samples of unequal sample sizes, which was developed for the estimation of the number of species and relies on the technique of rarefaction. In addition, it is shown that the measure of subdivision, θ ST, obtained when allelic richness is used in place ofh (Nei's index of diversity), is much larger than the F ST [e.g. θ ST(40)=0.52, where (40) indicates the specified sample used to estimate the allelic richness]. This suggests that rare alleles (which strongly influence measures of allelic richness) have a more scattered distribution than more frequent ones, a result which raises special conservation issues for the argan tree.

  2. The Seroprevalence of Hepatitis C Antibodies in Immigrants and Refugees from Intermediate and High Endemic Countries: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Greenaway, Christina; Thu Ma, Ann; Kloda, Lorie A; Klein, Marina; Cnossen, Sonya; Schwarzer, Guido; Shrier, Ian

    2015-01-01

    Hepatitis C virus (HCV) infection is a significant global health issue that leads to 350,000 preventable deaths annually due to associated cirrhosis and hepatocellular carcinoma (HCC). Immigrants and refugees (migrants) originating from intermediate/high HCV endemic countries are likely at increased risk for HCV infection due to HCV exposure in their countries of origin. The aim of this study was to estimate the HCV seroprevalence of the migrant population living in low HCV prevalence countries. Four electronic databases were searched from database inception until June 17, 2014 for studies reporting the prevalence of HCV antibodies among migrants. Seroprevalence estimates were pooled with a random-effect model and were stratified by age group, region of origin and migration status and a meta-regression was modeled to explore heterogeneity. Data from 50 studies representing 38,635 migrants from all world regions were included. The overall anti-HCV prevalence (representing previous and current infections) was 1.9% (95% CI, 1.4-2.7%, I2 96.1). Older age and region of origin, particularly Sub-Saharan Africa, Asia, and Eastern Europe were the strongest predictors of HCV seroprevalence. The estimated HCV seroprevalence of migrants from these regions was >2% and is higher than that reported for most host populations. Adult migrants originating from Asia, Sub-Saharan Africa and Eastern Europe are at increased risk for HCV and may benefit from targeted HCV screening.

  3. The Seroprevalence of Hepatitis C Antibodies in Immigrants and Refugees from Intermediate and High Endemic Countries: A Systematic Review and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Christina Greenaway

    Full Text Available Hepatitis C virus (HCV infection is a significant global health issue that leads to 350,000 preventable deaths annually due to associated cirrhosis and hepatocellular carcinoma (HCC. Immigrants and refugees (migrants originating from intermediate/high HCV endemic countries are likely at increased risk for HCV infection due to HCV exposure in their countries of origin. The aim of this study was to estimate the HCV seroprevalence of the migrant population living in low HCV prevalence countries.Four electronic databases were searched from database inception until June 17, 2014 for studies reporting the prevalence of HCV antibodies among migrants. Seroprevalence estimates were pooled with a random-effect model and were stratified by age group, region of origin and migration status and a meta-regression was modeled to explore heterogeneity.Data from 50 studies representing 38,635 migrants from all world regions were included. The overall anti-HCV prevalence (representing previous and current infections was 1.9% (95% CI, 1.4-2.7%, I2 96.1. Older age and region of origin, particularly Sub-Saharan Africa, Asia, and Eastern Europe were the strongest predictors of HCV seroprevalence. The estimated HCV seroprevalence of migrants from these regions was >2% and is higher than that reported for most host populations.Adult migrants originating from Asia, Sub-Saharan Africa and Eastern Europe are at increased risk for HCV and may benefit from targeted HCV screening.

  4. [Entomology of onchocercosis in Soconusco, Chiapas. 6. Quantitative studies of the transmission of Onchocerca volvulus by 3 species of Simuliidae in a community with high endemicity].

    Science.gov (United States)

    Ortega, M; Oliver, M; Ramírez, A

    1992-01-01

    In Guatemala, there is no doubt about the participation of Simulium ochraceum as vector of Onchocerciasis. However, in Mexico practically there are not studies focussed to determine the role of this species in the transmission. The objective of the present investigation was to determine which of the 3 species of Simulium founded in the Soconusco region of Chiapas, is the main, and which were secondary in the transmission of Onchocerciasis in that area. The locality of Morelos, in the Huixtla "municipio" of Chiapas, localized a 1200 meters over the sea level (mosl) were selected to carried out the present study. According to own parasitological studies, this locality is considered as highly endemic (more than 66% prevalence). From March 1979 to March, 1981, we performed captures of Simulium sp caught on human bait. Quantitative studies and of transmission potentials were also performed. The following results were obtained: a) Absolute black flies densities (nulliparous and pariparous) and infected black flies (with L1 and L2 larvae): S. ochraceum, S. metallicum and S. callidum, in that order was the distribution of densities. Infected black flies were obtained in the 3 species. However, in despite of an irregular distribution in all the year, it was possible to identify 2 peaks of maximum infection of S. ochraceum in March, 1979 and March 1981. b) Monthly bite densities and infective bites.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Tectonic and eustatic controls of late quaternary shelf sedimentation along the Central California (Santa Cruz) continental margin: high-resolution seismic stratigraphic evidence

    Science.gov (United States)

    Mullins, Henry T.; Nagel, David K.; Dominguez, Laura L.

    1985-07-01

    A high-resolution "uniboom", seismic stratigraphic investigation of a portion of the central California continental shelf has demonstrated that depositional patterns and sequences are controlled largely by an interplay of glacioeustatic sea-level fluctuations superimposed on local tectonics. Wrench tectonics, associated with active right-lateral shear along the San Gregorio fault zone, and the Pigeon Point Basement High control the location, distribution and overall geometry of depositional sequences via en echelon folding and differential subsidence. Areas of relatively thick and thin late Quaternary sediments conform in large part with structures produced during wrenching. Glacioeustatic sea-level oscillations have also shaped depositional patterns and sequences. Correlation of our seismic stratigraphic data with a southern California continental margin sea-level curve, suggests that during the last glacial maximum, approximately 18,000 yrs ago, a relative lowstand resulted in the erosion of a distinct unconformity upon which late Quaternary sediments have accumulated. A rapid rise of sea level to a relative stillstand, approximately 12,000 yrs ago, produced a concave-up, marine terrace profile across the mid-shelf, that has since been infilled with as much as 22 m of Holocene clastic sediments. A relative drop of sea level, approximately 11,000 yrs ago, allowed sediments to build seaward as a series of prograding clinoforms that form the basal sequences of the late Quaternary sediment fill. The succeeding Holocene transgression partially eroded the top of this earlier regressive sequence, and has now established a typical, wave-graded shelf along which sediments fine in a seaward direction to water depths of 90-100 m. At greater shelf water depths, surface sediments coarsen and appear to be relicts of previous relative sea-level lowstands. The presence of now submerged and buried marine terraces along both the central and southern California continental margins

  6. High-resolution geophysical data from the Inner Continental Shelf: South of Martha's Vineyard and north of Nantucket, Massachusetts

    Science.gov (United States)

    Ackerman, Seth D.; Brothers, Laura L.; Foster, David S.; Andrews, Brian D.; Baldwin, Wayne E.; Schwab, William C.

    2016-10-28

    The U.S. Geological Survey and the Massachusetts Office of Coastal Zone Management have cooperated to map approximately 185 square kilometers of the inner continental shelf south of Martha’s Vineyard and north of Nantucket, Massachusetts. This report contains geophysical data collected by the U.S. Geological Survey during a survey in 2013. The geophysical data include (1) swath bathymetry collected by using interferometric sonar, (2) acoustic backscatter from the interferometric sonar, and (3) seismic-reflection profiles from a chirp subbottom profiler. These spatial data support research on the Quaternary evolution of coastal Massachusetts, the influence of sea-level change and sediment supply on coastal evolution, and efforts to understand the type, distribution, and quality of subtidal marine habitats in the coastal ocean of Massachusetts.

  7. High prevalence of pathogenicLeptospira in wild and domesticated animals in an endemic area of China

    Institute of Scientific and Technical Information of China (English)

    Wang Yalin; Zeng Lingbing; Yang Hongliang; Xu Jianmin; Zhang Xiangyan; Guo Xiaokui; Pal Utpal; Qin Jinhong

    2011-01-01

    Objective:To assess the prevalence ofLeptospira detected in wildlife and domesticated animals in Jiangxi Province, China, in2009.Methods:Urine samples from 28 buffaloes and kidney samples from50 pigs,50 dogs and38 rats were collected from Fuliang and Shangrao County, Jiangxi Province, China, in October2009. Polymerase chain reaction(PCR) and culture analyses were used to detectLeptospira. The cultured isolates were typed using the microscopic agglutination test (MAT).Results:The results showed that rats potentially serve as the main reservoir of leptospiral infection, followed by dogs. Although16% of rats (6/38) were positive using culture analysis, PCR analysis using the diagnostic primersG1/G2 and B64I/B64II or lipL32 showed identification as50% and24%, respectively, of the rat samples as positive for the presence of leptospiralDNA.Conclusions:PCR-based detection of leptospiralDNA in infected kidney tissues of reservoirs is more efficient when usingG1/G2 primers thanlipL32 primers. However, the latter primers have a potential application for detection in urine samples. The alarmingly high prevalence of leptospiralDNAin the wild rat population near human habitation underscores the utility of routineLeptospira surveillance, preferably usingPCR methods, which are more sensitive than traditional culture-based methods.

  8. Single nucleotide polymorphism typing of Mycobacterium ulcerans reveals focal transmission of buruli ulcer in a highly endemic region of Ghana.

    Directory of Open Access Journals (Sweden)

    Katharina Röltgen

    Full Text Available Buruli ulcer (BU is an emerging necrotizing disease of the skin and subcutaneous tissue caused by Mycobacterium ulcerans. While proximity to stagnant or slow flowing water bodies is a risk factor for acquiring BU, the epidemiology and mode of M. ulcerans transmission is poorly understood. Here we have used high-throughput DNA sequencing and comparisons of the genomes of seven M. ulcerans isolates that appeared monomorphic by existing typing methods. We identified a limited number of single nucleotide polymorphisms (SNPs and developed a real-time PCR SNP typing method based on these differences. We then investigated clinical isolates of M. ulcerans on which we had detailed information concerning patient location and time of diagnosis. Within the Densu river basin of Ghana we observed dominance of one clonal complex and local clustering of some of the variants belonging to this complex. These results reveal focal transmission and demonstrate, that micro-epidemiological analyses by SNP typing has great potential to help us understand how M. ulcerans is transmitted.

  9. High levels of diversity uncovered in a widespread nominal taxon: continental phylogeography of the neotropical tree frog Dendropsophus minutus.

    Directory of Open Access Journals (Sweden)

    Marcelo Gehara

    Full Text Available Species distributed across vast continental areas and across major biomes provide unique model systems for studies of biotic diversification, yet also constitute daunting financial, logistic and political challenges for data collection across such regions. The tree frog Dendropsophus minutus (Anura: Hylidae is a nominal species, continentally distributed in South America, that may represent a complex of multiple species, each with a more limited distribution. To understand the spatial pattern of molecular diversity throughout the range of this species complex, we obtained DNA sequence data from two mitochondrial genes, cytochrome oxidase I (COI and the 16S rhibosomal gene (16S for 407 samples of D. minutus and closely related species distributed across eleven countries, effectively comprising the entire range of the group. We performed phylogenetic and spatially explicit phylogeographic analyses to assess the genetic structure of lineages and infer ancestral areas. We found 43 statistically supported, deep mitochondrial lineages, several of which may represent currently unrecognized distinct species. One major clade, containing 25 divergent lineages, includes samples from the type locality of D. minutus. We defined that clade as the D. minutus complex. The remaining lineages together with the D. minutus complex constitute the D. minutus species group. Historical analyses support an Amazonian origin for the D. minutus species group with a subsequent dispersal to eastern Brazil where the D. minutus complex originated. According to our dataset, a total of eight mtDNA lineages have ranges >100,000 km2. One of them occupies an area of almost one million km2 encompassing multiple biomes. Our results, at a spatial scale and resolution unprecedented for a Neotropical vertebrate, confirm that widespread amphibian species occur in lowland South America, yet at the same time a large proportion of cryptic diversity still remains to be discovered.

  10. High Levels of Diversity Uncovered in a Widespread Nominal Taxon: Continental Phylogeography of the Neotropical Tree Frog Dendropsophus minutus

    Science.gov (United States)

    Gehara, Marcelo; Crawford, Andrew J.; Orrico, Victor G. D.; Rodríguez, Ariel; Lötters, Stefan; Fouquet, Antoine; Barrientos, Lucas S.; Brusquetti, Francisco; De la Riva, Ignacio; Ernst, Raffael; Urrutia, Giuseppe Gagliardi; Glaw, Frank; Guayasamin, Juan M.; Hölting, Monique; Jansen, Martin; Kok, Philippe J. R.; Kwet, Axel; Lingnau, Rodrigo; Lyra, Mariana; Moravec, Jiří; Pombal, José P.; Rojas-Runjaic, Fernando J. M.; Schulze, Arne; Señaris, J. Celsa; Solé, Mirco; Rodrigues, Miguel Trefaut; Twomey, Evan; Haddad, Celio F. B.; Vences, Miguel; Köhler, Jörn

    2014-01-01

    Species distributed across vast continental areas and across major biomes provide unique model systems for studies of biotic diversification, yet also constitute daunting financial, logistic and political challenges for data collection across such regions. The tree frog Dendropsophus minutus (Anura: Hylidae) is a nominal species, continentally distributed in South America, that may represent a complex of multiple species, each with a more limited distribution. To understand the spatial pattern of molecular diversity throughout the range of this species complex, we obtained DNA sequence data from two mitochondrial genes, cytochrome oxidase I (COI) and the 16S rhibosomal gene (16S) for 407 samples of D. minutus and closely related species distributed across eleven countries, effectively comprising the entire range of the group. We performed phylogenetic and spatially explicit phylogeographic analyses to assess the genetic structure of lineages and infer ancestral areas. We found 43 statistically supported, deep mitochondrial lineages, several of which may represent currently unrecognized distinct species. One major clade, containing 25 divergent lineages, includes samples from the type locality of D. minutus. We defined that clade as the D. minutus complex. The remaining lineages together with the D. minutus complex constitute the D. minutus species group. Historical analyses support an Amazonian origin for the D. minutus species group with a subsequent dispersal to eastern Brazil where the D. minutus complex originated. According to our dataset, a total of eight mtDNA lineages have ranges >100,000 km2. One of them occupies an area of almost one million km2 encompassing multiple biomes. Our results, at a spatial scale and resolution unprecedented for a Neotropical vertebrate, confirm that widespread amphibian species occur in lowland South America, yet at the same time a large proportion of cryptic diversity still remains to be discovered. PMID:25208078

  11. Spontaneous viral clearance after 6-21 years of hepatitis B and C viruses coinfection in high HBV endemic area

    Institute of Scientific and Technical Information of China (English)

    Chun-Lei Fan; Lai Wei; Dong Jiang; Hong-Song Chen; Yan Gao; Ruo-Bing Li; Yu Wang

    2003-01-01

    AIM: To investigate the clinical and virological course of coinfection by hepatitis B virus (HBV) and hepatitis C virus (HCV) in China.METHODS: We enrolled 40 patients with chronic HBV and HCV coinfection (Group BC), 16 patients with chronic HBV infection (Group B) and 31 patients with chronic HCV infection (Group C). They infected HBV and/or HCV during 1982 to 1989.Sera of all the 87 patients were collected in 1994 and 2002respectively. We detected biochemical and virologic markers and serum HBV DNA and HCV RNA levels of all the patients. Btype ultrasound detection was performed in some patients.RESULTS: In Group BC, 67.5% of the patients cleared HBsAg,and 92.5% of the patients cleared HBeAg. The clearance rate of HBV DNA was 87.5%. There was no significant difference of HBV clearance between Group BC and Group B. In Group BC, 85.7% of males and 47.4% of females cleared HBV, and males were easier to clear HBV (x2=6.686, P=0.010). Such a tendency was also found in Group B. The clearance rate of HCV RNA in Group BC was 87.5%, significantly higher than that in Group C (x2=22.963, P<0.001). Less than 40% of the patients in all groups had elevated liver enzyme values. The highest value of alanine aminotransferase (ALT) was 218 u/L (normal range for ALT is 0-40 u/L). In most patients the ultrasonogram presentations changed mildly.CONCLUSION: The clinical manifestations of patients with HBV/HCV coinfection are mild and occult. High clearance rate of HBV and easy to clear HBV in male patients are the characteristics of HBV infection in adults in China. HBV can inhibit HCV replication, but no evidence has been found in our data that HCV suppresses HBV replication.

  12. Associated with Balkan Endemic Nephropathy

    Directory of Open Access Journals (Sweden)

    Ljubinka Jankovic-Velickovic

    2011-01-01

    Full Text Available The role of aristolochic acid in the etiology of Balkan endemic nephropathy (BEN and associated upper-tract urothelial carcinoma (UTUC has been recently confirmed. The aim of this study was to determine apoptosis-related marker(s specific for BEN-associated UTUC. Present investigation included 105 patients with UTUC, 44 from BEN region and 61 control tumors. Altered expression of Survivin was more often present in BEN UTUC with high grade and solid growth (P<0.005; P<0.05 than in control tumors. Significantly lower expression of proapoptotic marker Bax was found in BEN tumors with high grade, high stage, necrosis, and without metaplastic change (P<0.05; 0.05; 0.05; 0.05 compared to control tumors with the same features. Group (BEN-related/control, stage, growth pattern, and caspase 3 activity were significantly associated with the expression of Bax (P=0.002, 0.034, 0.047, 0.028, resp.,. This investigation identifies Bax as specific marker of BEN-associated UTUC. Decrease of pro-apoptotic protein Bax together with alteration of Survivin may be indicative for specific disturbances of intrinsic apoptotic pathway in UTUC arising in endemic areas.

  13. Predicting the Impact of Intervention Strategies for Sleeping Sickness in Two High-Endemicity Health Zones of the Democratic Republic of Congo.

    Directory of Open Access Journals (Sweden)

    Kat S Rock

    2017-01-01

    Full Text Available Two goals have been set for Gambian human African trypanosomiasis (HAT, the first is to achieve elimination as a public health problem in 90% of foci by 2020, and the second is to achieve zero transmission globally by 2030. It remains unclear if certain HAT hotspots could achieve elimination as a public health problem by 2020 and, of greater concern, it appears that current interventions to control HAT in these areas may not be sufficient to achieve zero transmission by 2030. A mathematical model of disease dynamics was used to assess the potential impact of changing the intervention strategy in two high-endemicity health zones of Kwilu province, Democratic Republic of Congo. Six key strategies and twelve variations were considered which covered a range of recruitment strategies for screening and vector control. It was found that effectiveness of HAT screening could be improved by increasing effort to recruit high-risk groups for screening. Furthermore, seven proposed strategies which included vector control were predicted to be sufficient to achieve an incidence of less than 1 reported case per 10,000 people by 2020 in the study region. All vector control strategies simulated reduced transmission enough to meet the 2030 goal, even if vector control was only moderately effective (60% tsetse population reduction. At this level of control the full elimination threshold was expected to be met within six years following the start of the change in strategy and over 6000 additional cases would be averted between 2017 and 2030 compared to current screening alone. It is recommended that a two-pronged strategy including both enhanced active screening and tsetse control is implemented in this region and in other persistent HAT foci to ensure the success of the control programme and meet the 2030 elimination goal for HAT.

  14. Predicting the Impact of Intervention Strategies for Sleeping Sickness in Two High-Endemicity Health Zones of the Democratic Republic of Congo

    Science.gov (United States)

    Torr, Steve J.; Lumbala, Crispin; Keeling, Matt J.

    2017-01-01

    Two goals have been set for Gambian human African trypanosomiasis (HAT), the first is to achieve elimination as a public health problem in 90% of foci by 2020, and the second is to achieve zero transmission globally by 2030. It remains unclear if certain HAT hotspots could achieve elimination as a public health problem by 2020 and, of greater concern, it appears that current interventions to control HAT in these areas may not be sufficient to achieve zero transmission by 2030. A mathematical model of disease dynamics was used to assess the potential impact of changing the intervention strategy in two high-endemicity health zones of Kwilu province, Democratic Republic of Congo. Six key strategies and twelve variations were considered which covered a range of recruitment strategies for screening and vector control. It was found that effectiveness of HAT screening could be improved by increasing effort to recruit high-risk groups for screening. Furthermore, seven proposed strategies which included vector control were predicted to be sufficient to achieve an incidence of less than 1 reported case per 10,000 people by 2020 in the study region. All vector control strategies simulated reduced transmission enough to meet the 2030 goal, even if vector control was only moderately effective (60% tsetse population reduction). At this level of control the full elimination threshold was expected to be met within six years following the start of the change in strategy and over 6000 additional cases would be averted between 2017 and 2030 compared to current screening alone. It is recommended that a two-pronged strategy including both enhanced active screening and tsetse control is implemented in this region and in other persistent HAT foci to ensure the success of the control programme and meet the 2030 elimination goal for HAT. PMID:28056016

  15. High Genetic Diversity and Insignificant Interspecific Differentiation in Opisthopappus Shih, an Endangered Cliff Genus Endemic to the Taihang Mountains of China

    Directory of Open Access Journals (Sweden)

    Rongmin Guo

    2013-01-01

    Full Text Available Opisthopappus Shih is endemic to the Taihang Mountains, China. It grows in the crevice of cliffs and is in fragmented distribution. This genus consists of two species, namely, O. taihangensis (Ling Shih and O. longilobus Shih, which are both endangered plants in China. This study adopted intersimple sequence repeat markers (ISSR to analyze the genetic diversity and genetic structure from different levels (genus, species, and population in this genus. A total of 253 loci were obtained from 27 primers, 230 of which were polymorphic loci with a proportion of polymorphic bands (PPB of up to 90.91% at genus level. At species level, both O. taihangensis (PPB=90.12%, H=0.1842, and I=0.289 and O. longilobus (PPB=95.21%, H=0.2226, and I=0.3542 have high genetic diversity. Their respective genetic variation mostly existed within the population. And genetic variation in O. longilobus (84.95% was higher than that in O. taihangensis (80.45%. A certain genetic differentiation among populations in O. taihangensis was found (Gst=0.2740, Φst=0.196 and genetic differentiation in O. longilobus was very small (Gst=0.1034, Φst=0.151. Gene flow in different degrees (Nm=1.325 and 4.336, resp. and mating system can form the existing genetic structures of these two species. Furthermore, genetic differentiation coefficient (Gst=0.0453 between species and the clustering result based on the genetic distance showed that interspecific differentiation between O. taihangensis and O. longilobus was not significant and could occur lately.

  16. Interspecific hybridization contributes to high genetic diversity and apparent effective population size in an endemic population of mottled ducks (Anas fulvigula maculosa)

    Science.gov (United States)

    Peters, Jeffrey L.; Sonsthagen, Sarah A.; Lavretsky, Philip; Rezsutek, Michael; Johnson, William P.; McCracken, Kevin G.

    2014-01-01

    Under drift-mutation equilibrium, genetic diversity is expected to be correlated with effective population size (Ne). Changes in population size and gene flow are two important processes that can cause populations to deviate from this expected relationship. In this study, we used DNA sequences from six independent loci to examine the influence of these processes on standing genetic diversity in endemic mottled ducks (Anas fulvigula) and geographically widespread mallards (A. platyrhynchos), two species known to hybridize. Mottled ducks have an estimated census size that is about two orders-of-magnitude smaller than that of mallards, yet these two species have similar levels of genetic diversity, especially at nuclear DNA. Coalescent analyses suggest that a population expansion in the mallard at least partly explains this discrepancy, but the mottled duck harbors higher genetic diversity and apparent N e than expected for its census size even after accounting for a population decline. Incorporating gene flow into the model, however, reduced the estimated Ne of mottled ducks to 33 % of the equilibrium Ne and yielded an estimated Ne consistent with census size. We also examined the utility of these loci to distinguish among mallards, mottled ducks, and their hybrids. Most putatively pure individuals were correctly assigned to species, but the power for detecting hybrids was low. Although hybridization with mallards potentially poses a conservation threat to mottled ducks by creating a risk of extinction by hybridization, introgression of mallard alleles has helped maintain high genetic diversity in mottled ducks and might be important for the adaptability and survival of this species.

  17. Genetic evidence for a high diversity and wide distribution of endemic strains of the pathogenic chytrid fungus Batrachochytrium dendrobatidis in wild Asian amphibians.

    Science.gov (United States)

    Bataille, Arnaud; Fong, Jonathan J; Cha, Moonsuk; Wogan, Guinevere O U; Baek, Hae Jun; Lee, Hang; Min, Mi-Sook; Waldman, Bruce

    2013-08-01

    Population declines and extinctions of amphibians have been attributed to the chytrid fungus Batrachochytrium dendrobatidis (Bd), especially one globally emerging recombinant lineage ('Bd-GPL'). We used PCR assays that target the ribosomal internal transcribed spacer region (ITS) of Bd to determine the prevalence and genetic diversity of Bd in South Korea, where Bd is widely distributed but is not known to cause morbidity or mortality in wild populations. We isolated Korean Bd strains from native amphibians with low infection loads and compared them to known worldwide Bd strains using 19 polymorphic SNP and microsatellite loci. Bd prevalence ranged between 12.5 and 48.0%, in 11 of 17 native Korean species, and 24.7% in the introduced bullfrog Lithobates catesbeianus. Based on ITS sequence variation, 47 of the 50 identified Korean haplotypes formed a group closely associated with a native Brazilian Bd lineage, separated from the Bd-GPL lineage. However, multilocus genotyping of three Korean Bd isolates revealed strong divergence from both Bd-GPL and the native Brazilian Bd lineages. Thus, the ITS region resolves genotypes that diverge from Bd-GPL but otherwise generates ambiguous phylogenies. Our results point to the presence of highly diversified endemic strains of Bd across Asian amphibian species. The rarity of Bd-GPL-associated haplotypes suggests that either this lineage was introduced into Korea only recently or Bd-GPL has been outcompeted by native Bd strains. Our results highlight the need to consider possible complex interactions among native Bd lineages, Bd-GPL and their associated amphibian hosts when assessing the spread and impact of Bd-GPL on worldwide amphibian populations.

  18. HCV and HBV coexist in HBsAg-negative patients with HCV viremia; possibility of coinfection in these patients must be considered in HBV-high endemic area

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dong Soon [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1998-01-01

    Hepatocellular carcinoma (HCC) is one of the most common cancers and is highly associated with HBV infection in Korea. It has been suggested that HCV core protein may impair the polymerase activity of HBV in vitro, potentially lowering HBV titre in coinfected patients. The aim of this study was to confirm the coexistence of HBV viremia in HCV infected patients HCC who have apparent HBsAg seronegativity. The serological profiles of HBV and HCV in 616 patients with HCC were analysed and coinfection rate of HBV and HCV investigated. Sera were obtained from 16 patients who were both anti-HCV and HCV RNA positive but HbsAg negative, and tested for HBV BY PCR. As a control group, sera were obtained from 15 patients with HCC and 30 non-A abd non-B chronic hepatitis patients without HCC; both were anti-HCV, HCV-RNA, and HBsAg negative and tested for HBV PCR. Of 616 patients with HCC, 450 (73.1 %) had current HBV infection, 48 (7.8 %) had anti-HCV antibodies, and nine (1.5 %) had viral markers of both HCV abd HBV by serological profiles. Of 27 the patients with HCV viremia and HBsAg seronegativity, 14 (51.9 %) showed HBV viremia by PCR. In contrast, of the 75 patients in the control group who were both HCV PCR negative and HBsAg negative, five (11.1 %) showed HBV viremia by PCR. The PCR for HBV revealed coexistent HBV viremia in HCV viremia patients, despite HBsAg negativity by EIA. In HBV-endemic areas, the possibility of coinfection of HBV in HBsAg-negative patients with HCV viremia should be considered and molecular analysis for HBV-DNA performed. (author). 18 refs., 4 tabs.

  19. Microphysical properties and high ice water content in continental and oceanic Mescoscale Convective Systems and potential implications for commercial aircraft at flight altitude

    Science.gov (United States)

    Gayet, J.-F.; Shcherbakov, V.; Bugliaro, L.; Protat, A.; Delanoë, J.; Pelon, J.; Garnier, A.

    2013-08-01

    Two complementary case studies are conducted to analyse convective system properties in the region where strong cloud-top lidar backscatter anomalies are observed as reported by Platt et al. (2011). These anomalies were reported for the first time using in-situ microphysical measurements in an isolated continental convective cloud over Germany during the CIRCLE2 experiment (Gayet et al., 2012). In this case, quasi collocated in situ observations with CALIPSO, CloudSat and Meteosat-9/SEVIRI observations confirm that regions of backscatter anomalies represent the most active and dense convective cloud parts with likely the strongest core updrafts and unusual high values of the particle concentration, extinction and ice water content (IWC), with the occurrence of small ice crystal sizes. Similar spaceborne observations are then analyzed in a maritime mesoscale cloud system (MCS) on 20 June 2008 located off the Brazil coast between 0° and 3° N latitude. Near cloud-top backscatter anomalies are evidenced in a region which corresponds to the coldest temperatures with maximum cloud top altitudes derived from collocated CALIPSO/IIR and Meteosat-9/SEVIRI infrared brightness temperatures. The interpretation of CALIOP data highlights significant differences of microphysical properties from those observed in the continental isolated convective cloud. Indeed, SEVIRI retrievals in the visible confirm much smaller ice particles near-top of the isolated continental convective cloud, i.e. effective radius (Reff) ~15 μm against 22-27 μm in the whole MCS area. 94 GHz Cloud Profiling Radar observations from CloudSat are then used to describe the properties of the most active cloud regions at and below cloud top. The cloud ice water content and effective radius retrieved with the CloudSat 2B-IWC and DARDAR inversion techniques, show that at usual cruise altitudes of commercial aircraft (FL 350 or ~10 700 m level), high IWC (i.e. up to 2 to 4 g m-3) could be identified according to

  20. Comparison of immune responses to a killed bivalent whole cell oral cholera vaccine between endemic and less endemic settings.

    Science.gov (United States)

    Desai, Sachin N; Akalu, Zenebe; Teferi, Mekonnen; Manna, Byomkesh; Teshome, Samuel; Park, Ju Yeon; Yang, Jae Seung; Kim, Deok Ryun; Kanungo, Suman; Digilio, Laura

    2016-02-01

    Studies on safety, immunogenicity and efficacy of the killed, bivalent whole cell oral cholera vaccine (Shanchol) have been conducted in historically endemic settings of Asia. Recent cholera vaccination campaigns in Haiti and Guinea have also demonstrated favourable immunogenicity and effectiveness in nonendemic outbreak settings. We performed a secondary analysis, comparing immune responses of Shanchol from two randomised controlled trials performed in an endemic and a less endemic area (Addis Ababa) during a nonoutbreak setting. While Shanchol may offer some degree of immediate protection in primed populations living in cholera endemic areas, as well as being highly immunogenic in less endemic settings, understanding the characteristics of immune responses in each of these areas is vital in determining ideal dosing strategies that offer the greatest public health impact to populations from areas with varying degrees of cholera endemicity. © 2015 John Wiley & Sons Ltd.

  1. High-temperature metamorphism during extreme thinning of the continental crust: a reappraisal of the north Pyrenean paleo-passive margin

    Directory of Open Access Journals (Sweden)

    C. Clerc

    2015-02-01

    Full Text Available An increasing number of field examples in mountain belts show that the formation of passive margins during extreme continent thinning may occur under conditions of high to very high thermal gradient beneath a thin cover of syn-rift sediments. Orogenic belts resulting from the tectonic inversion of distal margins and regions of exhumed continental mantle may exhibit high-temperature, low-pressure (HT-LP metamorphism and coeval syn-extensional, ductile deformation. Recent studies have shown that the northern flank of the Pyrenean belt, especially the North Pyrenean Zone, is one of the best examples of such inverted hot, passive margin. In this study, we provide a map of HT-LP metamorphism based on a dataset of more than one hundred peak-temperature estimates obtained using Raman spectroscopy of the carbonaceous material (RSCM. This dataset is completed by previous PT estimates based on mineral assemblages, and new Ar–Ar (amphibole, micas and U–Pb (titanite ages from metamorphic and magmatic rocks of the North Pyrenean Zone. The implications on the geological evolution of the Cretaceous Pyrenean paleomargins are discussed. Ages range mainly from 110 to 90 Ma and no westward or eastward propagation of the metamorphism and magmatism can be clearly identified. In contrast, the new data reveal a progressive propagation of the thermal anomaly from the base to the surface of the continental crust. Focusing on the key-localities of the Mauléon Basin, Arguenos-Moncaup, Lherz, Boucheville and the Bas-Agly, we analyse the thermal conditions prevailing during the Cretaceous crustal thinning. The results are synthetized into a series of three regional thematic maps, and into two detailed maps of the Arguenos-Moncaup and Lherz areas. The results indicate a first-order control of the thermal gradient by the intensity of crustal thinning. The highest grades of metamorphism are intimately associated with the areas where subcontinental mantle rocks have been

  2. Freshly brewed continental crust

    Science.gov (United States)

    Gazel, E.; Hayes, J. L.; Caddick, M. J.; Madrigal, P.

    2015-12-01

    Earth's crust is the life-sustaining interface between our planet's deep interior and surface. Basaltic crusts similar to Earth's oceanic crust characterize terrestrial planets in the solar system while the continental masses, areas of buoyant, thick silicic crust, are a unique characteristic of Earth. Therefore, understanding the processes responsible for the formation of continents is fundamental to reconstructing the evolution of our planet. We use geochemical and geophysical data to reconstruct the evolution of the Central American Land Bridge (Costa Rica and Panama) over the last 70 Ma. We also include new preliminary data from a key turning point (~12-6 Ma) from the evolution from an oceanic arc depleted in incompatible elements to a juvenile continental mass in order to evaluate current models of continental crust formation. We also discovered that seismic P-waves (body waves) travel through the crust at velocities closer to the ones observed in continental crust worldwide. Based on global statistical analyses of all magmas produced today in oceanic arcs compared to the global average composition of continental crust we developed a continental index. Our goal was to quantitatively correlate geochemical composition with the average P-wave velocity of arc crust. We suggest that although the formation and evolution of continents may involve many processes, melting enriched oceanic crust within a subduction zone, a process probably more common in the Achaean where most continental landmasses formed, can produce the starting material necessary for juvenile continental crust formation.

  3. Serological markers for monitoring historical changes in malaria transmission intensity in a highly endemic region of Western Kenya, 1994-2009.

    Science.gov (United States)

    Wong, Jacklyn; Hamel, Mary J; Drakeley, Chris J; Kariuki, Simon; Shi, Ya Ping; Lal, Altaf A; Nahlen, Bernard L; Bloland, Peter B; Lindblade, Kim A; Were, Vincent; Otieno, Kephas; Otieno, Peter; Odero, Chris; Slutsker, Laurence; Vulule, John M; Gimnig, John E

    2014-11-22

    period. However, retrospective analyses using datasets from 2007, 2008 and 2009 failed to detect any abrupt drop in transmission coinciding with the timing of the 1997-1999 ITN trial. In this highly endemic area, serological markers were useful for generating accurate point estimates of malaria transmission intensity, but not for retrospective analysis of historical changes. Further investigation, including exploration of different malaria antigens and/or alternative models of population seroconversion, may yield serological tools that are more informative in high transmission settings.

  4. Petrogenesis and its significance to continental dynamics of the Neogene high-potassium calc-alkaline volcanic rock association from north Qiangtang, Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    赖绍聪; 刘池阳; S.Y.O’Reilly

    2001-01-01

    Detailed studies indicate that the main rock type of the Neogene high-potassium calc-alkaline volcanic rock association from north Qiangtang is andesite, dacite and rhyolite. They belong to typical crust-generation magmatic system and originate from the special thickened crust of the Tibetan Plateau by dehydration melting. This group of rocks exhibits LREE enrichment but no remarkable Eu anomaly that shows their source region should be a thickened deep crust consisting of eclogitic mass group, implying that the crust had been thickened and an eclogitic deep crust had been formed during the Neogene period in Qiangtang area. This understanding is important and significant to making further discussion on the uplift mechanism and continental dynamics of the Tibetan Plateau.

  5. The endemic flora of Greece

    DEFF Research Database (Denmark)

    Tan, Kit

    2007-01-01

    The Balkan Peninsula has a rich endemic flora estimated as between 2600 and 2700 taxa; c. 750 are restricted to Greece. Conservationists consider the endemic flora of a country needs protection for all time; there is a tendency to paint an alarming picture. However, unless one knows something...... or quite a lot about the plants, no intelligent steps can be taken towards protecting them. 520 of the c. 750 endemics are listed on the Red Data "endangered list" by the Council of Europe in 1986 but few know the nature or extent of the threat. Work is currently in preparation on an Endemic Flora...

  6. Triassic-Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations (Junggar Basin, Ürümqi, China).

    Science.gov (United States)

    Sha, Jingeng; Olsen, Paul E; Pan, Yanhong; Xu, Daoyi; Wang, Yaqiang; Zhang, Xiaolin; Yao, Xiaogang; Vajda, Vivi

    2015-03-24

    Empirical constraints on orbital gravitational solutions for the Solar System can be derived from the Earth's geological record of past climates. Lithologically based paleoclimate data from the thick, coal-bearing, fluvial-lacustrine sequences of the Junggar Basin of Northwestern China (paleolatitude ∼60°) show that climate variability of the warm and glacier-free high latitudes of the latest Triassic-Early Jurassic (∼198-202 Ma) Pangea was strongly paced by obliquity-dominated (∼40 ky) orbital cyclicity, based on an age model using the 405-ky cycle of eccentricity. In contrast, coeval low-latitude continental climate was much more strongly paced by climatic precession, with virtually no hint of obliquity. Although this previously unknown obliquity dominance at high latitude is not necessarily unexpected in a high CO2 world, these data deviate substantially from published orbital solutions in period and amplitude for eccentricity cycles greater than 405 ky, consistent with chaotic diffusion of the Solar System. In contrast, there are indications that the Earth-Mars orbital resonance was in today's 2-to-1 ratio of eccentricity to inclination. These empirical data underscore the need for temporally comprehensive, highly reliable data, as well as new gravitational solutions fitting those data.

  7. The Myanmar continental shelf

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaswamy, V.; Rao, P.S.

    conditions, and neotectonic activity. The most prominent bathymetric feature on the Ayeyarwady continental shelf is the 120 km-wide Martaban Depression, at the centre of which is located the Martaban Canyon. Most of the suspended sediment discharge...

  8. Continental Scientific Drilling Program.

    Science.gov (United States)

    1979-01-01

    Resource Priorities in Continental Drilling J. J. Hemley 12 Aspects of Continental Crustal Structure and Growth Scott Smithson 13 Deep-Drilling Targets...Time of Workshop Allen F. Agnew Library of Congress Clarence R. Allen California Institute of Technology Orson L. Anderson University of California at...Skinner Yale University Norman H. Sleep Northwestern University Laurence L. Sloss Northwestern University Scott B. Smithson University of Wyoming

  9. Microphysical properties and high ice water content in continental and oceanic mesoscale convective systems and potential implications for commercial aircraft at flight altitude

    Science.gov (United States)

    Gayet, J.-F.; Shcherbakov, V.; Bugliaro, L.; Protat, A.; Delanoë, J.; Pelon, J.; Garnier, A.

    2014-01-01

    Two complementary case studies are conducted to analyse convective system properties in the region where strong cloud-top lidar backscatter anomalies are observed as reported by Platt et al. (2011). These anomalies were reported for the first time using in situ microphysical measurements in an isolated continental convective cloud over Germany during the CIRCLE2 experiment (Gayet et al., 2012). In this case, in situ observations quasi-collocated with CALIPSO (Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation), CloudSat and Meteosat-9/SEVIRI observations confirm that regions of backscatter anomalies represent the most active and dense convective cloud parts with likely the strongest core updrafts and unusually high values of the particle concentration, extinction and ice water content (IWC), with the occurrence of small ice crystal sizes. Similar spaceborne observations of a maritime mesoscale cloud system (MCS) located off the Brazilian coast between 0° and 3° N latitude on 20 June 2008 are then analysed. Near cloud-top backscatter anomalies are evidenced in a region which corresponds to the coldest temperatures with maximum cloud top altitudes derived from collocated CALIPSO/IIR and Meteosat-9/SEVIRI infrared brightness temperatures. The interpretation of CALIOP (Cloud Aerosol Lidar with Orthogonal Polarization) data highlights significant differences in microphysical properties from those observed in the continental isolated convective cloud. Indeed, SEVIRI (Spinning Enhanced Visible and InfraRed Imager) retrievals in the visible spectrum confirm much smaller ice particles near the top of the isolated continental convective cloud, i.e. effective radius (Reff) ~ 15 μm as opposed to 22-27 μm in the whole MCS area. Cloud profiling observations at 94 GHz from CloudSat are then used to describe the properties of the most active cloud regions at and below cloud top. The cloud ice-water content and effective radius retrieved with the CloudSat 2B

  10. High-Mg adakitic rocks and their complementary cumulates formed by crystal fractionation of hydrous mafic magmas in a continental crustal magma chamber

    Science.gov (United States)

    Ma, Qiang; Xu, Yi-Gang; Zheng, Jian-Ping; Sun, Min; Griffin, William L.; Wei, Ying; Ma, Liang; Yu, Xiaolu

    2016-09-01

    Understanding how adakitic magmas form is important for understanding the formation of the continental crust. Generating such high-Sr/Y rocks by crystal fractionation of basalts/basaltic andesites in magma chambers has been proposed in a wide range of tectonic settings. However, the complementary cumulates predicted by this scenario have rarely been observed. The late Triassic (~ 227 Ma) Ningcheng complex from the North China Craton is composed of a websterite - (Ol -/Hbl-) pyroxenite - gabbro unit and a quartz-diorite unit. They are interpreted as the products (cumulates and derivative melts, respectively) of fractionation from hydrous mafic magmas at mid- to lower-crustal pressures (4.9 ~ 8.3 kbar). The quartz diorites are high-Mg intermediate rocks with moderate SiO2 (57.0 ~ 62.9 wt%), high Mg# (> 49) and adakitic trace element signatures, such as high Sr (≥ 636 ppm) and light rare earth elements (REEs), low Y (≤ 17 ppm) and heavy REEs (Yb ≤ 1.8 ppm), lack of obvious Eu anomalies, and high Sr/Y (≥ 31) and La/Yb (≥ 24)). These adakitic signatures reflect differentiation of hydrous mantle-derived magmas in the deep crust, leaving behind a plagioclase-free residual solid assemblage in the early stages, which is represented by the coeval websterite-pyroxenite complex. This study therefore not only demonstrates that hydrous crystal fractionation is an important mechanism to form adakitic rocks, but also presents an example of a preserved fractionating system, i.e. high-Sr/Y rocks and their complementary cumulates. A geochemical comparison is made between representative adakitic rocks formed by fractionation of hydrous magmas and Archean TTGs. It is suggested that crystal fractionation is an efficient process for making Phanerozoic high Sr/Y rocks but was not responsible for the formation of Archean granitoids.

  11. On the possibility of high-velocity tidal sterams as dynamic barriers to longshore sediment transport: evidence from the continental shelf off the Gulf of Kutch, India

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, R.R.; Hashimi, N.H.; Rao, V.P.

    Differences in the bathymetry, bottom topography and the abundance of mica and clay minerals on the continental shelf north and south of the Gulf of Kutch, a macrotidal bay, indicate the presence of two distinct sedimentary environments...

  12. Shallow geological environment of Krishna–Godavari offshore, eastern continental margin of India as inferred from the interpretation of high resolution sparker data

    Indian Academy of Sciences (India)

    G Anitha; M V Ramana; T Ramprasad; P Dewangan; M Anuradha

    2014-03-01

    Krishna–Godavari offshore basin, a part of the eastern continental margin of India is a proven petroliferous basin. Recent drilling in this area in search of gas hydrates reveals that the upper ∼300 m thick Quaternary–Recent strata comprised of nannofossil bearing rich clays and, fractures/faults are the suitable zones for gas hydrates accumulation. Therefore, the knowledge about the shallow geological environments and its architecture are significantly important in assessing the gas hydrates potential of this area. In order to enhance the geological understanding, the newly acquired high resolution seismic (HRS) reflection data in this gas hydrates prone area is interpreted. The processed seismic sections show a maximum penetration of 562 ms TWT (∼450 m) underneath the seabed with high resolution stratification. An attempt has been made to: (i) deduce the shallow geological environment from the reflection characteristics, and, (ii) assign tentative ages under the constraints of drilling/coring results. We further explained the observed folded structures on the surface and subsurface through a mechanism linked to shale tectonism and neotectonic activity.

  13. Geochemistry of Paraná-Etendeka basalts from Misiones, Argentina: Some new insights into the petrogenesis of high-Ti continental flood basalts

    Science.gov (United States)

    Rämö, O. Tapani; Heikkilä, Pasi A.; Pulkkinen, Arto H.

    2016-04-01

    The Early Cretaceous (˜135-131 Ma) Paraná-Etendeka continental flood basalts, preserved in bulk in the Paraná basin of southern Brazil and vicinity, have been divided into low-Ti and high-Ti types that govern the southern and northern halves of the basin, respectively. We have examined a new sample set from the southern margin of the northern high-Ti segment of Paraná basalts in Misiones, northeastern Argentina. These basalts are strongly to moderately enriched in TiO2 (2-4 wt.%), have relatively high Ti/Y (300-500), low MgO (3.5-6.5 wt.%), and high Fe (FeO(tot) 12-14 wt.%) and belong to the Pitanga and Paranapanema magma types of Peate et al. (1992). Nd and Sr isotope compositions are quite unvarying with ɛNd (at 133 Ma) values of -4.6 to -3.6 and initial 87Sr/86Sr of 0.7054-0.7059 and show no variation with fractionation. Compared to high-Ti lavas in the central and northern parts of the Paraná high-Ti basalt segment, the lavas from Misiones are similar to those in the northeastern magin of the basin but less radiogenic in initial Nd isotope composition than those in the central part. This variation probably reflects mixed EM1-EM2 source components in the sublithospheric mantle. A polybaric melt model of a sublithospheric mantle source at the garnet lherzolite-spinel lherzolite transition is compatible with the observed Ti budget of the Pitanga and Paranapanema lavas, regardless of the Nd isotope composition of their purported source.

  14. Glacial erosion of high-elevation low-relief summits on passive continental margins constrained by cosmogenic nuclides

    DEFF Research Database (Denmark)

    Andersen, Jane Lund; Egholm, David Lundbek; Knudsen, Mads Faurschou

    We present a new, extensive in-situ cosmogenic 10Be and 26Al dataset from high-elevation low-relief summits along Sognefjorden in Norway. Contrary to previous studies of high-elevation low-relief summits in cold regions, we find only limited cosmogenic nuclide inheritance in bedrock surfaces......, indicating that warm-based ice eroded the summits during the last glacial period. From the isotope concentrations we model denudation histories using a recently developed Monte Carlo Markov Chain inversion model (Knudsen et al, 2015). The model relies on the benthic d18O curve (Lisiecki and Raymo, 2005...

  15. Evidence of correlated evolution of hypsodonty and exceptional longevity in endemic insular mammals.

    Science.gov (United States)

    Jordana, Xavier; Marín-Moratalla, Nekane; DeMiguel, Daniel; Kaiser, Thomas M; Köhler, Meike

    2012-08-22

    Here, we test whether the increase in tooth height in insular endemics results from the expansion of the dietary niche under resource limitation, as widely considered, or whether it represents an investment in dental durability in response to the selection for extended longevity under low levels of extrinsic mortality. We tested these hypotheses in the extremely hypsodont fossil bovid Myotragus balearicus from the Balearic Islands, an ideal model to study the evolutionary trends on islands. Dental abrasion was significantly lower in the insular bovid than in highly hypsodont continental artiodactyls, suggesting that feeding habits are not the sole driving force behind increased crown height. However, the estimated longevity for M. balearicus based on dental durability was two times that predicted from body mass. Survivorship curves confirm that an extraordinarily large number of individuals approached the longevity of the species. Our results, hence, provide evidence that hypsodonty in insular endemics is the outcome of selection for increased durability of the permanent dentition in association with an extended lifespan. In the context of insularity, our results lend additional support to the disposable soma theory of ageing confirming the dependency of somatic maintenance and repair on lifespan, and its control by resource availability and extrinsic mortality.

  16. The endemic flora of Greece

    DEFF Research Database (Denmark)

    Tan, Kit

    2007-01-01

    The Balkan Peninsula has a rich endemic flora estimated as between 2600 and 2700 taxa; c. 750 are restricted to Greece. Conservationists consider the endemic flora of a country needs protection for all time; there is a tendency to paint an alarming picture. However, unless one knows something...... of Greece. Three volumes are envisaged: the first deals with the Peloponnese; the second will cover Crete and the islands and the third, the rest of mainland Greece. It is planned to have a sound and scientific basis for plant conservation and education. Within the Balkans more than 60% of the endemic taxa...

  17. Raising the continental crust

    Science.gov (United States)

    Campbell, Ian H.; Davies, D. Rhodri

    2017-02-01

    The changes that occur at the boundary between the Archean and Proterozoic eons are arguably the most fundamental to affect the evolution of Earth's continental crust. The principal component of Archean continental crust is Granite-Greenstone Terranes (GGTs), with granites always dominant. The greenstones consist of a lower sequence of submarine komatiites and basalts, which erupted onto a pre-existing Tonalite-Trondhjemite-Granodiorite (TTG) crust. These basaltic rocks pass upwards initially into evolved volcanic rocks, such as andesites and dacites and, subsequently, into reworked felsic pyroclastic material and immature sediments. This transition coincides with widespread emplacement of granitoids, which stabilised (cratonised) the continental crust. Proterozoic supra-crustal rocks, on the other hand, are dominated by extensive flat-lying platform sequences of mature sediments, which were deposited on stable cratonic basements, with basaltic rocks appreciably less abundant. The siliceous TTGs cannot be produced by direct melting of the mantle, with most hypotheses for their origin requiring them to be underlain by a complimentary dense amphibole-garnet-pyroxenite root, which we suggest acted as ballast to the early continents. Ubiquitous continental pillow basalts in Archean lower greenstone sequences require the early continental crust to have been sub-marine, whereas the appearance of abundant clastic sediments, at higher stratigraphic levels, shows that it had emerged above sea level by the time of sedimentation. We hypothesise that the production of komatiites and associated basalts, the rise of the continental crust, widespread melting of the continental crust, the onset of sedimentation and subsequent cratonisation form a continuum that is the direct result of removal of the continent's dense amphibole-garnet-pyroxenite roots, triggered at a regional scale by the arrival of a mantle plume at the base of the lithosphere. Our idealised calculations suggest

  18. High-Resolution Chirp and Mini-Sparker Seismic-Reflection Data From the Southern California Continental Shelf - Gaviota to Mugu Canyon

    Science.gov (United States)

    Sliter, Ray W.; Triezenberg, Peter J.; Hart, Patrick E.; Draut, Amy E.; Normark, William R.; Conrad, James E.

    2008-01-01

    The U.S. Geological Survey (USGS) collected high-resolution shallow seismic-reflection data in September, 2007, and June-July, 2008, from the continental shelf offshore of southern California between Gaviota and Mugu Canyon, in support of the California's State Waters Mapping Program. Data were acquired using SIG 2mille mini-sparker and Edgetech chirp 512 instruments aboard the R/V Zephyr (Sept. 2007) and R/V Parke Snavely (June-July 2008). The survey area spanned approximately 120 km of coastline, and included shore-perpendicular transects spaced 1.0-1.5 km apart that extended offshore to at least the 3-mile limit of State waters, in water depths ranging from 10 m near shore to 300 m near the offshore extent of Mugu and Hueneme submarine canyons. Subbottom acoustic penetration spanned tens to several hundred meters, variable by location. This report includes maps of the surveyed transects, linked to Google Earth software, as well as digital data files showing images of each transect in SEG-Y, JPEG, and TIFF formats. The images of sediment deposits, tectonic structure, and natural-gas seeps collected during this study provide geologic information that is essential to coastal zone and resource management at Federal, State and local levels, as well as to future research on the sedimentary, tectonic, and climatic record of southern California.

  19. Rapid, High-Resolution Detection of Environmental Change over Continental Scales from Satellite Data - the Earth Observation Data Cube

    Science.gov (United States)

    Lewis, Adam; Lymburner, Leo; Purss, Matthew B. J.; Brooke, Brendan; Evans, Ben; Ip, Alex; Dekker, Arnold G.; Irons, James R.; Minchin, Stuart; Mueller, Norman

    2015-01-01

    The effort and cost required to convert satellite Earth Observation (EO) data into meaningful geophysical variables has prevented the systematic analysis of all available observations. To overcome these problems, we utilise an integrated High Performance Computing and Data environment to rapidly process, restructure and analyse the Australian Landsat data archive. In this approach, the EO data are assigned to a common grid framework that spans the full geospatial and temporal extent of the observations - the EO Data Cube. This approach is pixel-based and incorporates geometric and spectral calibration and quality assurance of each Earth surface reflectance measurement. We demonstrate the utility of the approach with rapid time-series mapping of surface water across the entire Australian continent using 27 years of continuous, 25 m resolution observations. Our preliminary analysis of the Landsat archive shows how the EO Data Cube can effectively liberate high-resolution EO data from their complex sensor-specific data structures and revolutionise our ability to measure environmental change.

  20. Cotrimoxazole for childhood febrile illness in Malaria-endemic regions

    African Journals Online (AJOL)

    of Plasmodium falcipanlm parasitaemia in child- ren younger than 5 ... an effective single treatment for febrile illness in young children in ... highly endemic areas all young children with fever should be treated ... parental consent. Children who ...

  1. Seismic probing of continental subduction zones

    Science.gov (United States)

    Zhao, Liang; Xu, Xiaobing; Malusà, Marco G.

    2017-09-01

    High-resolution images of Earth's interior provide pivotal information for the understanding of a range of geodynamic processes, including continental subduction and exhumation of ultrahigh-pressure (UHP) metamorphic rocks. Here we present a synthesis of available global seismic observations on continental subduction zones, and selected examples of seismic probing from the European Alps, the Himalaya-Tibet and the Qinling-Dabie orogenic belts. Our synthesis and examples show that slabs recognized beneath exhumed continental UHP terranes generally have shallow dip angles (100 km. Slabs underlined by a clear high velocity anomaly from Earth's surface to the mantle are generally Cenozoic in age. Some of these slabs are continuous, whereas other continental subduction zones are located above discontinuous high velocity anomalies possibly suggesting slab breakoff. The density of seismic stations and the quality of recordings are of primary importance to get high-resolution images of the upper mantle to be used as a starting point to provide reliable geodynamic interpretations. In some cases, areas previously indicated as possible site of slab breakoff, such as the European Alps, have been later proven to be located above a continuous slab by using higher quality travel time data from denser seismic arrays. Discriminating between oceanic and continental slabs can be challenging, but valuable information can be provided by combining teleseismic tomography and receiver function analysis. The upper mantle beneath most continental UHP terranes generally shows complex seismic anisotropy patterns that are potentially preserved even in pre-Cenozoic subduction zones. These patterns can be used to provide information on continental slabs that are no longer highlighted by a clear high-velocity anomaly.

  2. Nuclear genetic diversity in human lice (Pediculus humanus reveals continental differences and high inbreeding among worldwide populations.

    Directory of Open Access Journals (Sweden)

    Marina S Ascunce

    Full Text Available Understanding the evolution of parasites is important to both basic and applied evolutionary biology. Knowledge of the genetic structure of parasite populations is critical for our ability to predict how an infection can spread through a host population and for the design of effective control methods. However, very little is known about the genetic structure of most human parasites, including the human louse (Pediculus humanus. This species is composed of two ecotypes: the head louse (Pediculus humanus capitis De Geer, and the clothing (body louse (Pediculus humanus humanus Linnaeus. Hundreds of millions of head louse infestations affect children every year, and this number is on the rise, in part because of increased resistance to insecticides. Clothing lice affect mostly homeless and refugee-camp populations and although they are less prevalent than head lice, the medical consequences are more severe because they vector deadly bacterial pathogens. In this study we present the first assessment of the genetic structure of human louse populations by analyzing the nuclear genetic variation at 15 newly developed microsatellite loci in 93 human lice from 11 sites in four world regions. Both ecotypes showed heterozygote deficits relative to Hardy-Weinberg equilibrium and high inbreeding values, an expected pattern given their parasitic life history. Bayesian clustering analyses assigned lice to four distinct genetic clusters that were geographically structured. The low levels of gene flow among louse populations suggested that the evolution of insecticide resistance in lice would most likely be affected by local selection pressures, underscoring the importance of tailoring control strategies to population-specific genetic makeup and evolutionary history. Our panel of microsatellite markers provides powerful data to investigate not only ecological and evolutionary processes in lice, but also those in their human hosts because of the long

  3. Imaging continental shelf shallow stratigraphy by using different high-resolution seismic sources: an example from the Calabro-Tyrrhenian margin (Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Eleonora Martorelli

    2010-01-01

    Full Text Available High-resolution seismic reflection profiles of the Calabro-Tyrrhenian continental shelf were collected using different seismic sources (Sub-Bottom Profiler, Uniboom, Sparker 0.5-1-4.5 kJ. Noticeable differences and results were obtained both from a geophysical and geological-interpretative point of view. The availability of different sources permitted the definition of the most suitable seismostratigraphic characterization in terms of resolution, penetration and acoustic facies. Very high resolution stratigraphy was defined through profiles produced by different seismic systems used in parallel. This permitted the application of sequence-stratigraphy concepts with the reconstruction of a thick postglacial depositional sequence, formed by a transgressive and a high-stand systems tract. The thickness distribution of postglacial deposits reveals that the main depocenter (55-65 m is located offshore of the Coastal Range, along a stretch of coast supplied by several small and seasonal streams ("fiumare" and characterized by the lack of a coastal plain. This suggests the greater efficiency of sediment supply and bypass in this area relatively to sectors located offshore of the main rivers. The transgressive systems tract, usually thin or nearly absent, is particularly well developed (up to 33 m and is composed of up to three parasequences with a retrogradational stacking pattern. The high-stand systems tract, up to 30 m thick, is made up of two parasequences and has a quite regular geometry and acoustic facies.Perfis de reflexão sísmica de alta resolução da plataforma continental tirreniana de Calabro foram obtidos utilizando-se recursos sísmicos diversos (Perfilador de Sub-superfície, Uniboom, Sparker 0.5-1-4.5 kJ. Diferenças evidentes foram encontradas sob o ponto de vista geofísico e geológico-interpretativo. A disponibilidade de diferentes fontes permitiu a definição de uma caracterização sismo-estratigráfica mais acurada em termos

  4. Assessing the risk of dengue virus transmission in a non-endemic city surrounded by endemic and hyperendemic areas

    Directory of Open Access Journals (Sweden)

    Tsz Ho Kwan

    2017-02-01

    Conclusions: The cumulative exposure of Hong Kong residents to dengue has so far been low. Coupled with the lack of a spatial relationship between exposed cases and vector intensities, a high risk of local transmission of DENV is not supported. The apparently higher exposure likelihood of females could be explained by past infection in workers from dengue endemic countries, while frequent travel could have exposed older adults to DENV. Continued surveillance, risk assessment, and intensive vector control remain essential to prevent the transformation of a non-endemic to an endemic city.

  5. Continental growth seen through the sedimentary record

    Science.gov (United States)

    Dhuime, Bruno; Hawkesworth, Chris J.; Delavault, Hélène; Cawood, Peter A.

    2017-07-01

    Sedimentary rocks and detrital minerals sample large areas of the continental crust, and they are increasingly seen as a reliable archive for its global evolution. This study presents two approaches to model the growth of the continental crust through the sedimentary archive. The first builds on the variations in U-Pb, Hf and O isotopes in global databases of detrital zircons. We show that uncertainty in the Hf isotope composition of the mantle reservoir from which new crust separated, in the 176Lu/177Hf ratio of that new crust, and in the contribution in the databases of zircons that experienced ancient Pb loss(es), adds some uncertainty to the individual Hf model ages, but not to the overall shape of the calculated continental growth curves. The second approach is based on the variation of Nd isotopes in 645 worldwide fine-grained continental sedimentary rocks with different deposition ages, which requires a correction of the bias induced by preferential erosion of younger rocks through an erosion parameter referred to as K. This dimensionless parameter relates the proportions of younger to older source rocks in the sediment, to the proportions of younger to older source rocks present in the crust from which the sediment was derived. We suggest that a Hadean/Archaean value of K = 1 (i.e., no preferential erosion), and that post-Archaean values of K = 4-6, may be reasonable for the global Earth system. Models built on the detrital zircon and the fine-grained sediment records independently suggest that at least 65% of the present volume of continental crust was established by 3 Ga. The continental crust has been generated continuously, but with a marked decrease in the growth rate at 3 Ga. The period from > 4 Ga to 3 Ga is characterised by relatively high net rates of continental growth (2.9-3.4 km3 yr- 1 on average), which are similar to the rates at which new crust is generated (and destroyed) at the present time. Net growth rates are much lower since 3 Ga (0

  6. Taenia solium in Europe: Still endemic?

    Science.gov (United States)

    Devleesschauwer, Brecht; Allepuz, Alberto; Dermauw, Veronique; Johansen, Maria V; Laranjo-González, Minerva; Smit, G Suzanne A; Sotiraki, Smaragda; Trevisan, Chiara; Wardrop, Nicola A; Dorny, Pierre; Gabriël, Sarah

    2017-01-01

    The pork tapeworm, Taenia solium, causes an important economic and health burden, mainly in rural or marginalized communities of sub-Saharan Africa, Asia, and Latin-America. Although improved pig rearing conditions seem to have eliminated the parasite in most Western European countries, little is known about the true endemicity status of T. solium throughout Europe. Three recent reviews indicate that autochthonous human T. solium taeniasis/cysticercosis may be possible in Europe, but that current peer-reviewed literature is biased towards Western Europe. Officially reported data on porcine cysticercosis are highly insufficient. Favourable conditions for local T. solium transmission still exist in eastern parts of Europe, although the ongoing integration of the European Union is speeding up modernisation and intensification of the pig sector. Further evidence is urgently needed to fill the gaps on the European T. solium endemicity map. We urge to make human cysticercosis notifiable and to improve the reporting of porcine cysticercosis.

  7. Effectiveness and cost effectiveness of screening immigrants schemes for tuberculosis (TB) on arrival from high TB endemic countries to low TB prevalent countries.

    Science.gov (United States)

    Sanneh, A F N S; Al-Shareef, A M

    2014-09-01

    Immigrants to developed countries are a major source of TB. Therefore amongst strategies adopted for TB control in developed countries include; 1) Screening immigrants at ports of entry referred to as "Port of Arrival Screening" (PoA) and 2) Passive screening (PS) for TB which means screening immigrants through general practices, hospitals, chest-clinics and emergency departments. Evidence of the effectiveness and cost effectiveness of these strategies is not consistent. Evaluate efficiency of active PoA TB screening for immigrants from TB endemic-regions compared with Passive Screening of immigrant-populations from TB endemic-regions. Major electronic-databases and reference lists of relevant studies were searched. Experts of immigrants' TB screening were contacted for additional studies published or unpublished. Systematic search of major databases identified only retrospective cohort-studies. Their qualities were assessed using Scottish Intercollegiate Guidelines Network (SIGN) methodological checklist for comparative cohort-studies. Systematic electronic searches identified 1443 citations. Of these 74 studies were retrieved for evaluation against the review's inclusion/exclusion criteria (see study inclusion/exclusion criteria). Four studies met the inclusion criteria (figure 2) which were low in the evidence hierarchy of primary effectiveness studies and had heterogeneities between them. Thus descriptive data-synthesis was performed. Proportionately PoA screening had the lowest percentage of receipt of tuberculin skin test (TST) and the highest percentage of non-attendance for TST reading (table 2). Active PoA screening reduced infectiousness by 34% compared to 30% by passive screening and new entrants screened at PoA were 80% less likely to be hospitalised Odds ratio (OR) = 0.2 (95% confidence interval (CI) 0.1 - 0.2). [Table: see text]. One cost effectiveness analysis was found that compared the costs of; active PoA screening, general practice screening and

  8. Updated Global Burden of Cholera in Endemic Countries

    Science.gov (United States)

    Ali, Mohammad; Nelson, Allyson R.; Lopez, Anna Lena; Sack, David A.

    2015-01-01

    Background The global burden of cholera is largely unknown because the majority of cases are not reported. The low reporting can be attributed to limited capacity of epidemiological surveillance and laboratories, as well as social, political, and economic disincentives for reporting. We previously estimated 2.8 million cases and 91,000 deaths annually due to cholera in 51 endemic countries. A major limitation in our previous estimate was that the endemic and non-endemic countries were defined based on the countries’ reported cholera cases. We overcame the limitation with the use of a spatial modelling technique in defining endemic countries, and accordingly updated the estimates of the global burden of cholera. Methods/Principal Findings Countries were classified as cholera endemic, cholera non-endemic, or cholera-free based on whether a spatial regression model predicted an incidence rate over a certain threshold in at least three of five years (2008-2012). The at-risk populations were calculated for each country based on the percent of the country without sustainable access to improved sanitation facilities. Incidence rates from population-based published studies were used to calculate the estimated annual number of cases in endemic countries. The number of annual cholera deaths was calculated using inverse variance-weighted average case-fatality rate (CFRs) from literature-based CFR estimates. We found that approximately 1.3 billion people are at risk for cholera in endemic countries. An estimated 2.86 million cholera cases (uncertainty range: 1.3m-4.0m) occur annually in endemic countries. Among these cases, there are an estimated 95,000 deaths (uncertainty range: 21,000-143,000). Conclusion/Significance The global burden of cholera remains high. Sub-Saharan Africa accounts for the majority of this burden. Our findings can inform programmatic decision-making for cholera control. PMID:26043000

  9. Lithospheric structure and continental geodynamics

    Institute of Scientific and Technical Information of China (English)

    许忠淮; 石耀霖

    2003-01-01

    This paper briefly reviews main progress in the research on lithospheric structure and continental geodynamics made by Chinese geophysicists during last 4 years since 22nd IUGG general assembly in July 1999. The research mainly covers the following fields: investigations on regional lithospheric structure, DSS survey of crust and upper mantle velocity structure, study on present-day inner movement and deformation of Chinese mainland by analyzing GPS observations, geodynamics of Qingzang plateau, geophysical survey of the Dabie-Sulu ultra-high pressure metamorphic belt and probing into its formation mechanism, geophysical observations in sedimentary basins and study on their evolution process, and plate dynamics, etc.

  10. Effective anthelmintic therapy of residents living in endemic area of high prevalence for Hookworm and Schistosoma mansoni infections enhances the levels of allergy risk factor anti-Der p1 IgE

    Directory of Open Access Journals (Sweden)

    Sabrina S. Campolina

    2015-01-01

    Full Text Available In this work were investigated the relationship between Hookworm/Schistosoma mansoni infections and allergy related risk factors in two endemic areas with distinct prevalence of infections and co-infection. The intensity of infections, eosinophilia, allergy risk factors, infections status and anti-Der p1 IgE levels before and 2 years (population 1 and 3 years (population 2 after anthelmintic treatment, were evaluated. It was observed that the population with lower prevalence and intensity of infection (population 2 had lower eosinophils counts (>600/mm3 and higher animal contact than the population with higher parasites intensity (population 1. After anthelmintic treatment the intensity of S. mansoni single infection decreased, but no changes were observed in Hookworm and co-infected individuals. The anthelmintic treatment also enhanced anti-Der p1 IgE optical density in ELISA on the subgroups that became negative for helminth infection regardless of their previous infection condition in population 1. Facing that, we evaluated the anti-Der p1 IgE reactivity index, and the ratio (after/before treatment was significantly higher in patients co-infected before treatment. On the other hand, no association between anti-Der p1 IgE reactivity index and the intensity of infections were observed. In conclusion, effective anthelmintic therapy of subjects from endemic areas with high prevalence of Hookworm and S. mansoni infections enhances anti-Der p1 IgE levels.

  11. The Jungfraujoch high-alpine research station (3454 m) as a background clean continental site for the measurement of aerosol parameters

    Energy Technology Data Exchange (ETDEWEB)

    Nyeki, S.; Baltensperger, U.; Jost, D.T.; Weingartner, E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Colbeck, I. [Essex Univ., Colchester (United Kingdom)

    1997-09-01

    Aerosol physical parameter measurements are reported here for the first full annual set of data from the Jungfraujoch site. Comparison to NOAA background and regional stations indicate that the site may be designated as `clean continental` during the free tropospheric influenced period 03:00 -09:00. (author) figs., tab., refs.

  12. Study of geomorphological changes by high quality DEMs, obtained from UAVs-Structure from Motion in highest continental cliffs of Europe: A Capelada (Galicia, Spain)

    Science.gov (United States)

    Muñoz Narciso, Efrén; García, Horacio; Sierra Pernas, Chema; Pérez-Alberti, Augusto

    2017-04-01

    This study analyses the geomorphological evolution of a highly dynamic coastal environment, one of the higher cliffs in Continental Europe (A Capelada, NW Spain), using Structure from Motion-Multi View Stereoscan techniques (hereafter referred to as SfM-MVS). Comparing orthoimages from the last 10 years we observed several topographical changes in one specific valley (Teixidelo). Interestingly, these changes were caused by 2 different processes: (i) heavy coastal erosion and (ii) slow complex landslides, working in opposite directions. The main challenge was obtaining high quality topographical data for quantifying the changes during the last few years using low cost-high quality techniques in remote areas. Unmanned Aerial Vehicle platforms (drones, hereafter referred to as UAVs) and SFM-MVS offer ultrahigh-density topographical data. Furthermore, the use of drones and SfM-MVS close range images requires new applications in geomorphology for understanding the workflow and limitations. In this paper we present the 2 main results: (i) a centimeter spatial resolution DEM from august 2016 was obtained using a @DJI Phantom 3 advanced model drone. The pictures were processed in Agisoft PhotoScan Pro 1.2.6 version by SfM-MVS techniques, generating a high-density point cloud (i.e. ˜2000 points/m2) with 3mm of RMSE (i.e. the point cloud was georeferenced in a geographical coordinates system using ˜40 Ground Control Points obtained from differential RTK-GPS and a Total Station network) and (ii) a DEM of Differences, which compares official freely available 2010 LiDAR data (i.e. ˜2 points/m2) with a 2016 DEM derived by UAVs-SfM, where we have observed meter-scale elevation changes (i.e. sediment and erosion processes). During this time, 75% of the sediment has been mobilized. The novel UAVs and SfM-MVS techniques prove to be great for advancing the study of geomorphological processes in remote areas.

  13. The effect of removing potentially infectious dogs on the numbers of canine Leishmania infantum infections in an endemic area with high transmission rates.

    Science.gov (United States)

    Grimaldi, Gabriel; Teva, Antonio; Santos, Claudiney B; Ferreira, Adelson L; Falqueto, Aloísio

    2012-06-01

    To assess the effect of the rapid removal of potentially infectious dogs on the prevalence and incidence of canine infections, a prospective study was undertaken in an area endemic for Leishmania infantum. We used serological testing based on the rapid DPP rK28 fusion protein chromatographic immunoassay for this dog screening-and-culling intervention trial. The outcome was evaluated by measuring seropositivity and sero-conversion/-reversion rates for canine infection. Our estimates indicated that concomitant detection and elimination of seropositive dogs with active disease may affect the numbers of canine infections and disease burden temporarily, although it is insufficient as a measure to interrupt the zoonotic L. infantum transmission. However, most of the asymptomatic, seropositive dogs continuously exhibit low levels of antibodies and/or reverted, remaining seronegative thereafter. In the process of waiting for an effective vaccine, one option for canine reservoir control may be to identify these possibly genetically resistant animals and promote their expansion in the population.

  14. Phylogeography of the Pacific Blueline Surgeonfish, Acanthurus nigroris, Reveals High Genetic Connectivity and a Cryptic Endemic Species in the Hawaiian Archipelago

    Directory of Open Access Journals (Sweden)

    Joseph D. DiBattista

    2011-01-01

    Full Text Available Understanding genetic connectivity is fundamental to the design of marine protected areas in the service of ecosystem-scale management. Here we evaluate such trends for a Pacific surgeonfish (Acanthurus nigroris; N=544 at two spatial scales: (1 within the Hawaiian archipelago, and (2 across the entire species range from the central to southwest Pacific. The mtDNA cytochrome b data reveal genetic divergence (d=0.041 between Hawaii and the rest of the Pacific range indicating a cryptic species pair, with one taxon endemic to Hawaii. Johnston Atoll, 1400 km SW of Hawaii, also has the Hawaiian species but is distinct from most Hawaiian locations in population genetic comparisons, indicating the limits of gene flow for this widespread reef species. No consistent population genetic differences were observed among Hawaiian sites or among the other Pacific island sites. We also detected a modest bias in gene flow from the southeast towards the northwest islands of the Hawaiian Archipelago, indicating that the Papahānaumokuākea Marine National Monument may be a recipient, rather than a source of propagules to replenish reef resources.

  15. Serological based monitoring of a cohort of patients with chronic Chagas disease treated with benznidazole in a highly endemic area of northern Argentina

    Directory of Open Access Journals (Sweden)

    Leticia L Niborski

    2016-06-01

    Full Text Available This study aimed to evaluate well-documented diagnostic antigens, named B13, 1F8 and JL7 recombinant proteins, as potential markers of seroconversion in treated chagasic patients. Prospective study, involving 203 patients treated with benznidazole, was conducted from endemic areas of northern Argentina. Follow-up was possible in 107 out of them and blood samples were taken for serology and PCR assays before and 2, 3, 6, 12, 24 and 36 months after treatment initiation. Reactivity against Trypanosoma cruzi lysate and recombinant antigens was measured by ELISA. The rate of decrease of antibody titers showed nonlinear kinetics with an abrupt drop within the first three months after initiation of treatment for all studied antigens, followed by a plateau displaying a low decay until the end of follow-up. At this point, anti-B13, anti-1F8 and anti-JL7 titers were relatively close to the cut-off line, while anti-T. cruzi antibodies still remained positive. At baseline, 60.8% (45/74 of analysed patients tested positive for parasite DNA by PCR and during the follow-up period in 34 out of 45 positive samples (75.5% could not be detected T. cruzi DNA. Our results suggest that these antigens might be useful as early markers for monitoring antiparasitic treatment in chronic Chagas disease.

  16. Centers of endemism and diversity patterns for typhlocybine leafhoppers (Hemiptera: Cicadellidae: Typhlocybinae) in China.

    Science.gov (United States)

    Yuan, Shuai; Huang, Min; Wang, Xiu-Shuang; Ji, Li-Qiang; Zhang, Ya-Lin

    2014-08-01

    This study identifies 'centers of endemism' for typhlocybine leafhoppers in China, revealing diversity patterns and congruence of patterns between total species richness and endemism. Distribution patterns of 774 Typhlocybinae (607 described and 167 undescribed species) were mapped on a 1.5° × 1.5° latitude/longitude grid. Total species richness, endemic species richness and weighted endemism richness were calculated for each grid cell. Grid cells within the top 5% highest values of weighted endemism richness were considered as 'centers of endemism'. Diversity patterns by latitude and altitude were obtained through calculating the gradient richness. A congruence of diversity patterns between total species richness and endemism was confirmed using correlation analysis. To investigate the bioclimatic factors (19 variables) contributing to the congruence between total species richness and endemism, we compared the factor's difference between non-endemic and endemic species using the Kruskal-Wallis test. Eleven centers of endemism, roughly delineated by mountain ranges, were identified in central and southern China, including the south Yunnan, Hengduan Mountains, Qinling Mountains, Hainan Island, Taiwan Island and six mountain areas located in western Sichuan, northwest Fujian, southeast Guizhou, southeast Hunan, central and western Guangdong, and north Zhejiang. Total species richness and endemic species richness decreased with increased latitude and had a consistent unimodal response to altitude. The proportions of endemism decreased with increased latitude and increased with rising altitude. Diversity patterns between total species richness and endemism were highly consistent, and 'Precipitation of Coldest Period' and 'Temperature of Coldest Period' may contribute to the congruence of pattern. Migration ability may play a role in the relationship of endemism and species richness; climate, environment factors and important geologic isolation events can also play

  17. Early Cretaceous continental delamination in the Yangtze Block: Evidence from high-Mg adakitic intrusions along the Tanlu fault, central Eastern China

    Science.gov (United States)

    Jia, Liqiong; Mo, Xuanxue; Santosh, M.; Yang, Zhusen; Yang, Dan; Dong, Guochen; Wang, Liang; Wang, Xinchun; Wu, Xuan

    2016-09-01

    Early Cretaceous high-Mg adakitic rocks from central Eastern China provide important insights into the thinning mechanism of the over-thickened lithosphere in the Yangtze Block (YB) as well as the North China Block (NCB). The Tanlu fault (TLF), located between the North China and Yangtze Blocks, and has been considered as a prominent pathway of magmas and fluids that resulted in lithosphere thinning of the YB during the Mesozoic-Cenozoic. Here we report the petrology, whole-rock geochemistry, zircon U-Pb geochronology, in situ Hf isotopes, and whole-rock Sr-Nd-Pb isotopes of four high-Mg adakitic intrusions along the TLF in northeastern Langdai. These adakitic intrusions consist of monzodiorite, quartz monzonite porphyry, and quartz monzodiorite. Zircon LA-MC-ICPMS analyses of five samples yield weighted mean 206Pb/238U ages of 127.58 ± 0.80, 126.90 ± 0.81, 120.71 ± 0.64, 122.75 ± 0.57, and 129.2 ± 1.1 Ma, indicating their emplacement during the Early Cretaceous. The intrusions have intermediate SiO2 (53.18-65.48 wt%) and high potassium (K2O = 3.07-3.95 wt%; Na2O/K2O = 1.02-1.26) and are classified as shoshonitic to high-K calc-alkaline series. They are characterized by high MgO (1.80-7.35 wt%), Mg# (50-65), Sr (591-1183 ppm), Ni (20.3-143.0 ppm), and Cr (51.40-390.0 ppm) contents, high (La/Yb)N (11.60-28.33) and Sr/Y (27.9-113.5) ratios, and low Y (7.79-22.4 ppm) and Yb (0.60-2.01 ppm) contents, comparable with high-Mg adakites. The samples are enriched in light rare earth elements but depleted in heavy rare earth elements and high field strength elements with slightly negative to positive Eu anomalies (δEu = 0.81-1.30), resembling the features of high-Mg adakitic rocks. Their whole-rock εNd(t) = -16.2 to -15.0, initial (87Sr/86Sr)i = 0.7060-0.7074, low radiogenic Pb (206Pb/204Pb(t) = 16.208-16.509, 207Pb/204Pb(t) = 15.331-15.410, and 208Pb/204Pb(t) = 36.551-36.992), and zircon εHf(t) = -36.6 to -16.6 suggest magma derivation from a continental crustal

  18. Controlling endemic cholera with oral vaccines.

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    Ira M Longini

    2007-11-01

    Full Text Available BACKGROUND: Although advances in rehydration therapy have made cholera a treatable disease with low case-fatality in settings with appropriate medical care, cholera continues to impose considerable mortality in the world's most impoverished populations. Internationally licensed, killed whole-cell based oral cholera vaccines (OCVs have been available for over a decade, but have not been used for the control of cholera. Recently, these vaccines were shown to confer significant levels of herd protection, suggesting that the protective potential of these vaccines has been underestimated and that these vaccines may be highly effective in cholera control when deployed in mass immunization programs. We used a large-scale stochastic simulation model to investigate the possibility of controlling endemic cholera with OCVs. METHODS AND FINDINGS: We construct a large-scale, stochastic cholera transmission model of Matlab, Bangladesh. We find that cholera transmission could be controlled in endemic areas with 50% coverage with OCVs. At this level of coverage, the model predicts that there would be an 89% (95% confidence interval [CI] 72%-98% reduction in cholera cases among the unvaccinated, and a 93% (95% CI 82%-99% reduction overall in the entire population. Even a more modest coverage of 30% would result in a 76% (95% CI 44%-95% reduction in cholera incidence for the population area covered. For populations that have less natural immunity than the population of Matlab, 70% coverage would probably be necessary for cholera control, i.e., an annual incidence rate of < or = 1 case per 1,000 people in the population. CONCLUSIONS: Endemic cholera could be reduced to an annual incidence rate of < or = 1 case per 1,000 people in endemic areas with biennial vaccination with OCVs if coverage could reach 50%-70% depending on the level of prior immunity in the population. These vaccination efforts could be targeted with careful use of ecological data.

  19. Spatial distribution of Madeira Island Laurisilva endemic spiders (Arachnida: Araneae)

    Science.gov (United States)

    2014-01-01

    Abstract Madeira island presents a unique spider diversity with a high number of endemic species, many of which are still poorly known. A recent biodiversity survey on the terrestrial arthropods of the native forest, Laurisilva, provided a large set of standardized samples from various patches throughout the island. Out of the fifty two species recorded, approximately 33.3% are Madeiran endemics, many of which had not been collected since their original description. Two new species to science are reported – Ceratinopsis n. sp. and Theridion n. sp. – and the first records of Poeciloneta variegata (Blackwall, 1841) and Tetragnatha intermedia Kulczynski, 1891 are reported for the first time for Madeira island. Considerations on species richness and abundance from different Laurisilva locations are presented, together with distribution maps for endemic species. These results contribute to a better understanding of spider diversity patterns and endemic species distribution in the native forest of Madeira island. PMID:24855443

  20. Spatial distribution of Madeira Island Laurisilva endemic spiders (Arachnida: Araneae

    Directory of Open Access Journals (Sweden)

    Luís Crespo

    2014-02-01

    Full Text Available Madeira island presents a unique spider diversity with a high number of endemic species, many of which are still poorly known. A recent biodiversity survey on the terrestrial arthropods of the native forest, Laurisilva, provided a large set of standardized samples from various patches throughout the island. Out of the fifty two species recorded, approximately 33.3% are Madeiran endemics, many of which had not been collected since their original description. Two new species to science are reported – Ceratinopsis n. sp. and Theridion n. sp. – and the first records of Poeciloneta variegata (Blackwall, 1841 and Tetragnatha intermedia Kulczynski, 1891 are reported for the first time for Madeira island. Considerations on species richness and abundance from different Laurisilva locations are presented, together with distribution maps for endemic species. These results contribute to a better understanding of spider diversity patterns and endemic species distribution in the native forest of Madeira island.

  1. [Endemic goiter in Latium: environmental and genetic factors].

    Science.gov (United States)

    Paggi, A

    1998-01-01

    Most studies on the pathogenesis of endemic goiter focus above all on iodine deficiency. In some endemic goiter areas (i.e. Nigeria) there is no evidence of iodine deficiency; therefore, we suggest the taking into account of various factors, both environmental and non-environmental. We report the results of two studies carried out in three different areas in Latium: one of them (Cerveteri, RM) could be classified as high prevalence of goiter area, while the two others (Roccasecca dei Volsci, LT and Castel San Pietro Romano, RM) are true endemic goiter areas. The role of environmental factors, radioactivity and electromagnetism, foodstuff, the hydrogeological and chemical composition of natural water and the importance of genetics are here discussed, assuming that the endemic goiter could have a multifactorial pathogenesis.

  2. THERMAL CONTINENTALISM IN EUROPE

    Directory of Open Access Journals (Sweden)

    APOSTOL L.

    2015-03-01

    Full Text Available In the context of current climate changes, this article aims to highlight the continental characteristics of Europe’s climate (including a temporal evolution, regarding the multiannual thermal averages. For this purpose, 78 meteorological stations have been selected, placed approximately on two pairs of transects on West-East and South-North directions. The data were extracted from www.giss.nasa.gov (NASA Goddard Institute for Space Studies, statistically processed (Open Office and mapped (www.saga-gis.org. For the lapse of time 1961-2010, the analysis of multiannual temperature averages has shown the following: if the multiannual average temperature is strongly influenced by latitude, its deviations are more dependent on longitude; the multiannual average thermal amplitude, as well as the Gorczynski continentality index, are strongly related to longitude; their temporal evolution has shown a significant decrease in the Eastern half of the continent and an increase (although less significant in Western Europe.

  3. Rickettsia (Rickettsiales: Rickettsiaceae) Vector Biodiversity in High Altitude Atlantic Forest Fragments Within a Semiarid Climate: A New Endemic Area of Spotted-Fever in Brazil.

    Science.gov (United States)

    Moerbeck, Leonardo; Vizzoni, Vinícius F; Machado-Ferreira, Erik; Cavalcante, Robson C; Oliveira, Stefan V; Soares, Carlos A G; Amorim, Marinete; Gazêta, Gilberto S

    2016-11-01

    Rickettsioses are re-emerging vector-borne zoonoses with a global distribution. Recently, Rickettsia sp. strain Atlantic rainforest has been associated with new human spotted-fever (SF) cases in Brazil, featuring particular clinical signs: eschar formation and lymphadenopathy. These cases have been associated with the tick species, Amblyomma ovale From 2010 until 2015, the Brazilian Health Department confirmed 11 human SF cases in the Maciço de Baturité region, Ceará, Brazil. The present study reports the circulation of Rickettsia spp. in vectors from this entirely new endemic area for SF. A total of 1,727 ectoparasites were collected in this area from the environment, humans, and wild and domestic animals. Samples (n = 887) were screened by polymerase chain reaction (PCR), targeting the gltA and ompA rickettsial genes. Sequencing and phylogenetic analyses of gltA gene amplicons were carried out for 13 samples positive for both screening PCRs. Fragments of gltA and ompA from three samples were cloned, sequenced, and analyzed further. A. ovale and Rhipicephalus sanguineus specimens, collected from dogs, were found to be infected with Rickettsia sp. str. Atlantic rainforest, suggesting the importance of dogs in the epidemic cycle. Candidatus Rickettsia andeanae, Rickettsia felis, and Rickettsia bellii were also found infecting ticks and fleas in five municipalities, demonstrating the broad diversity of rickettsiae in circulation in the studied area. This study reports, for the first time, evidence of infection with Rickettsia sp. strain Atlantic rainforest in A. ovale and R. sanguineus in Ceará, and Ca. R. andeanae in an Atlantic rainforest environment of Brazil. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. An eclogite-bearing continental tectonic slice in the Zermatt-Saas high-pressure ophiolites at Trockener Steg (Zermatt, Swiss Western Alps)

    Science.gov (United States)

    Weber, Sebastian; Bucher, Kurt

    2015-09-01

    The Theodul Glacier Unit (TGU) at "Trockener Steg" represents a continental slice, embedded within the ophiolitic Zermatt-Saas Zone. The Zermatt-Saas Zone is the remnant of the Piemonte-Liguria oceanic lithosphere, formed in the middle Jurassic and subducted up to eclogite facies conditions in the Early Tertiary. The close spatial association of the TGU to the Zermatt-Saas Zone permits a comparison of the metamorphic evolution of the units by detailed field mapping and a petrological investigation of eclogites. The eclogites from both tectono-metamorphic units can be clearly distinguished by their textures, mineral assemblages and by mineral and bulk-rock composition. Geothermobarometry and computed assemblage stability diagrams for the TGU eclogites indicate P-T conditions of 2.2 ± 0.1 GPa and 580 ± 50 °C. These derived P-T conditions must be considered as minimum peak metamorphic conditions the rocks achieved during subduction. The P-T data are different from those derived for eclogites of Zermatt-Saas Zone adjacent to the Theodul Glacier Unit, that reached maximal burial depths at 2.3-2.4 GPa and 500 ± 50 °C. While the estimates of the eclogites of Zermatt-Saas Zone are in good agreement with some of the previous studies, the contrasting P-T estimates for the TGU eclogites suggest that the Zermatt-Saas complex must be subdivided into several tectonic subunits. The non-uniform peak conditions over the "Trockener Steg" area and the maximum pressures conditions reported from ultra-high pressure localities within Zermatt-Saas Zone suggest, that individual tectonic slices have been assembled after detachment from the slab at the return-point, i.e. along the exhumation path. Detached packages of rocks may range from small tectonic slices up to several kilometer-sized fragments. The TGU is separated from the surrounding rocks of the ophiolite unit by two major tectonic contacts. In addition, the formation of biotite-rich crusts along the basal contact of the TGU

  5. Prediction of phylogeographic endemism in an environmentally complex biome.

    Science.gov (United States)

    Carnaval, Ana Carolina; Waltari, Eric; Rodrigues, Miguel T; Rosauer, Dan; VanDerWal, Jeremy; Damasceno, Roberta; Prates, Ivan; Strangas, Maria; Spanos, Zoe; Rivera, Danielle; Pie, Marcio R; Firkowski, Carina R; Bornschein, Marcos R; Ribeiro, Luiz F; Moritz, Craig

    2014-10-07

    Phylogeographic endemism, the degree to which the history of recently evolved lineages is spatially restricted, reflects fundamental evolutionary processes such as cryptic divergence, adaptation and biological responses to environmental heterogeneity. Attempts to explain the extraordinary diversity of the tropics, which often includes deep phylogeographic structure, frequently invoke interactions of climate variability across space, time and topography. To evaluate historical versus contemporary drivers of phylogeographic endemism in a tropical system, we analyse the effects of current and past climatic variation on the genetic diversity of 25 vertebrates in the Brazilian Atlantic rainforest. We identify two divergent bioclimatic domains within the forest and high turnover around the Rio Doce. Independent modelling of these domains demonstrates that endemism patterns are subject to different climatic drivers. Past climate dynamics, specifically areas of relative stability, predict phylogeographic endemism in the north. Conversely, contemporary climatic heterogeneity better explains endemism in the south. These results accord with recent speleothem and fossil pollen studies, suggesting that climatic variability through the last 250 kyr impacted the northern and the southern forests differently. Incorporating sub-regional differences in climate dynamics will enhance our ability to understand those processes shaping high phylogeographic and species endemism, in the Neotropics and beyond.

  6. Endemic harvestmen and spiders of Austria (Arachnida: Opiliones, Araneae

    Directory of Open Access Journals (Sweden)

    Komposch, Christian

    2011-01-01

    Full Text Available A comprehensive overview of plant, fungus and animal species of Austria revealed a total of 748 endemic and subendemic species, including, 11 harvestman and 46 spider species. Altogether two endemic harvestmen (Nemastoma bidentatum relictum, Nemastoma schuelleri and 8 endemic spiders (Abacoproeces molestus, Collinsia (caliginosa nemenziana, Mughiphantes severus, Mughiphantes styriacus, Pelecopsis alpica, Scotophaeus nanus, Troglohyphantes novicordis, Troglohyphantes tauriscus, beside 9 subendemic harvestman and 38 subendemic spider species have been recorded from Austria. Hot-spots of endemism in the Eastern Alps are the north-eastern (Ennstaler Alps and southern Calcareous Alps (Karawanken, Karnische Alps and the Central Alps (Hohe Tauern, Gurktaler Alps, Ötztaler and Stubaier Alps. Most of the endemic arachnid species occur from the nival down to the montane zone. Important habitats are rocky areas, caves and woodlands. High absolute numbers and percentages of endemics can be found within the harvestman families Cladonychiidae, Ischyropsalididae and Nemastomatidae and in the spider genera Lepthyphantes s. l. and Troglohyphantes. The conservation status of these highly endangered taxa – 85 % of the spider species and 100 % of the harvestman taxa are endangered in Austria – is poor.

  7. Lu-Hf systematics of the ultra-high temperature Napier Complex, East Antarctica: evidence for the early Archean formation of continental crust

    Science.gov (United States)

    Choi, S.; Mukasa, S. B.; Andronikov, A. V.; Osanai, Y.; Harley, S. L.; Kelly, N. M.

    2009-12-01

    The Napier Complex in East Antarctica comprises some of the oldest rocks on earth (~3.8 billion years old), overprinted by an ultra-high temperature (UHT) metamorphic event near the Archean-Proterozoic boundary. Garnet, orthopyroxene, sapphirine, osumilite, rutile and a whole rock representing an equilibrated assemblage from this belt yield a Lu-Hf isochron age of 2,403 ± 43 Ma. Preservation of the UHT mineral assemblage in the rock analyzed suggests rapid cooling with closure likely to have occurred for the Lu-Hf system at post-peak UHT conditions near a temperature of ~800C. Individual zircon grains from Gage Ridge within the Napier Complex yielded a remarkably uniform range of 176Hf/177Hf values between 0.280433 ± 7 and 0.280505 ± 10, corresponding to ɛHf > +5.6 at 3.85 Ga relative to the chondritic uniform reservoir (CHUR). Because of their exceedingly low Lu/Hf values (<0.001), the grains are effectively recording the initial Hf isotope composition of the magmatic systems from which the gneiss protoliths crystallized. These results indicate that (1) the source of the crustal materials that formed the Napier Complex at 3.85 Ga were depleted relative to the CHUR. The extent of depletion involved is higher than has been predicted by extrapolation from the Lu-Hf isotopic evolution inferred for the source of Proterozoic and Phanerozoic basalts, judging from an fLu/Hf value of 0.51, (2) the depleted mantle reservoir has been in existence since very early in Earth’s history, in agreement with the early differentiation of the Earth that the latest core formation models require, and (3) an extremely depleted source also mean that the bulk of continental crust was extracted from the mantle by ~3.8 Ga. Moreover, the results demonstrate that even the oldest silicic rocks in the complex are not likely to have formed from remobilized older crustal materials, but were instead juvenile products of mantle melting. In addition, zircons with metamorphic rims have a similar

  8. Tsunami Detection by High Frequency Radar Beyond the Continental Shelf: II. Extension of Time Correlation Algorithm and Validation on Realistic Case Studies

    Science.gov (United States)

    Grilli, Stéphan T.; Guérin, Charles-Antoine; Shelby, Michael; Grilli, Annette R.; Moran, Patrick; Grosdidier, Samuel; Insua, Tania L.

    2017-08-01

    In past work, tsunami detection algorithms (TDAs) have been proposed, and successfully applied to offline tsunami detection, based on analyzing tsunami currents inverted from high-frequency (HF) radar Doppler spectra. With this method, however, the detection of small and short-lived tsunami currents in the most distant radar ranges is challenging due to conflicting requirements on the Doppler spectra integration time and resolution. To circumvent this issue, in Part I of this work, we proposed an alternative TDA, referred to as time correlation (TC) TDA, that does not require inverting currents, but instead detects changes in patterns of correlations of radar signal time series measured in pairs of cells located along the main directions of tsunami propagation (predicted by geometric optics theory); such correlations can be maximized when one signal is time-shifted by the pre-computed long wave propagation time. We initially validated the TC-TDA based on numerical simulations of idealized tsunamis in a simplified geometry. Here, we further develop, extend, and apply the TC algorithm to more realistic tsunami case studies. These are performed in the area West of Vancouver Island, BC, where Ocean Networks Canada recently deployed a HF radar (in Tofino, BC), to detect tsunamis from far- and near-field sources, up to a 110 km range. Two case studies are considered, both simulated using long wave models (1) a far-field seismic, and (2) a near-field landslide, tsunami. Pending the availability of radar data, a radar signal simulator is parameterized for the Tofino HF radar characteristics, in particular its signal-to-noise ratio with range, and combined with the simulated tsunami currents to produce realistic time series of backscattered radar signal from a dense grid of cells. Numerical experiments show that the arrival of a tsunami causes a clear change in radar signal correlation patterns, even at the most distant ranges beyond the continental shelf, thus making an

  9. Transient regional climate change: analysis of the summer climate response in a high-resolution, century-scale, ensemble experiment over the continental United States.

    Science.gov (United States)

    Diffenbaugh, Noah S; Ashfaq, Moetasim; Scherer, Martin

    2011-12-27

    Integrating the potential for climate change impacts into policy and planning decisions requires quantification of the emergence of sub-regional climate changes that could occur in response to transient changes in global radiative forcing. Here we report results from a high-resolution, century-scale, ensemble simulation of climate in the United States, forced by atmospheric constituent concentrations from the Special Report on Emissions Scenarios (SRES) A1B scenario. We find that 21(st) century summer warming permanently emerges beyond the baseline decadal-scale variability prior to 2020 over most areas of the continental U.S. Permanent emergence beyond the baseline annual-scale variability shows much greater spatial heterogeneity, with emergence occurring prior to 2030 over areas of the southwestern U.S., but not prior to the end of the 21(st) century over much of the southcentral and southeastern U.S. The pattern of emergence of robust summer warming contrasts with the pattern of summer warming magnitude, which is greatest over the central U.S. and smallest over the western U.S. In addition to stronger warming, the central U.S. also exhibits stronger coupling of changes in surface air temperature, precipitation, and moisture and energy fluxes, along with changes in atmospheric circulation towards increased anticylonic anomalies in the mid-troposphere and a poleward shift in the mid-latitude jet aloft. However, as a fraction of the baseline variability, the transient warming over the central U.S. is smaller than the warming over the southwestern or northeastern U.S., delaying the emergence of the warming signal over the central U.S. Our comparisons with observations and the Coupled Model Intercomparison Project Phase 3 (CMIP3) ensemble of global climate model experiments suggest that near-term global warming is likely to cause robust sub-regional-scale warming over areas that exhibit relatively little baseline variability. In contrast, where there is greater

  10. Transient regional climate change: analysis of the summer climate response in a high-resolution, century-scale, ensemble experiment over the continental United States

    Science.gov (United States)

    Diffenbaugh, Noah S.; Ashfaq, Moetasim; Scherer, Martin

    2013-01-01

    Integrating the potential for climate change impacts into policy and planning decisions requires quantification of the emergence of sub-regional climate changes that could occur in response to transient changes in global radiative forcing. Here we report results from a high-resolution, century-scale, ensemble simulation of climate in the United States, forced by atmospheric constituent concentrations from the Special Report on Emissions Scenarios (SRES) A1B scenario. We find that 21st century summer warming permanently emerges beyond the baseline decadal-scale variability prior to 2020 over most areas of the continental U.S. Permanent emergence beyond the baseline annual-scale variability shows much greater spatial heterogeneity, with emergence occurring prior to 2030 over areas of the southwestern U.S., but not prior to the end of the 21st century over much of the southcentral and southeastern U.S. The pattern of emergence of robust summer warming contrasts with the pattern of summer warming magnitude, which is greatest over the central U.S. and smallest over the western U.S. In addition to stronger warming, the central U.S. also exhibits stronger coupling of changes in surface air temperature, precipitation, and moisture and energy fluxes, along with changes in atmospheric circulation towards increased anticylonic anomalies in the mid-troposphere and a poleward shift in the mid-latitude jet aloft. However, as a fraction of the baseline variability, the transient warming over the central U.S. is smaller than the warming over the southwestern or northeastern U.S., delaying the emergence of the warming signal over the central U.S. Our comparisons with observations and the Coupled Model Intercomparison Project Phase 3 (CMIP3) ensemble of global climate model experiments suggest that near-term global warming is likely to cause robust sub-regional-scale warming over areas that exhibit relatively little baseline variability. In contrast, where there is greater

  11. Richness and endemism of the freshwater fishes of Mexico

    Directory of Open Access Journals (Sweden)

    T. Contreras-MacBeath

    2014-02-01

    Full Text Available A study of richness and endemism of the freshwater fishes of Mexico, was carried out in order to identify hotspots and inform conservation efforts. This was done by mapping and overlaying individual species distributions by means of geographical information systems based on museum data. The study was able to confirm several previously proposed centres of freshwater fish richness (Southeastern Mexico, the Mesa Central, the Bravo-Conchos river system and the Panuco and Tuxpan-Nautla rivers. Seven areas with high ‘Corrected Weighted Endemism’ Index values were identified, with the valley of Cuatrociénegas recognized as a true centre. An alarming result was the identification of a “Ghost” centre of endemism (Llanos El Salado in southwestern Nuevo León, where six endemic cyprinodont species are all ‘extinct’ or ‘extinct in the wild’. Forty-nine single site endemics that are distributed all over Mexico were identified. The Chichancanab lagoon in the border between Yucatan and Quintana Roo, where a flock composed of six endemic cyprinodonts is present needs special mention. Three hotspots of richness plus endemism were found in Mexico, the most important of which is the Mesa Central where impacts by human activities have had a detrimental effect on fish populations.

  12. Aligning conservation goals: are patterns of species richness and endemism concordant at regional scales?

    OpenAIRE

    Ricketts, T. H.

    2001-01-01

    Biodiversity conservation strategies commonly target areas of high species richness and/or high endemism. However, the correlation between richness and endemism at scales relevant to conservation is unclear; these two common goals of conservation plans may therefore be in conflict. Here the spatial concordance between richness and endemism is tested using five taxa in North America: butterflies, birds, mammals, amphibians, and reptiles. This concordance is also tested using overall indices of...

  13. Clay mineral distribution in the continental shelf and slope off Saurashtra, West coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, V.P.

    the Deccan trap coastal province is the predominant clay mineral in the sediments of the continental shelf south of the Gulf of Kutch. Lateral variations reveal that the montmorillonite contents are high in the innershelf and on the continental slope...

  14. Biogeographical note on Antarctic microflorae: Endemism and cosmopolitanism

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    Waqar Azeem Jadoon

    2013-11-01

    Full Text Available This study deals with the biogeography of Antarctic microflora (Antarctica acts as best model to study microbial biogeography such as cyanobacteria and selected halophiles with special emphasis on Halomonas variabilis and Bacillus licheniformis. Halophiles are known to be resistant not only to salt stress, but also to extreme temperature, pressure, and aridity and they are capable of surviving in harsh environments such as polar regions, deep-sea habitats, and deserts. Many microbes are known to be resistant to hostile environmental conditions, and are capable of surviving in harsh environments. Our group has isolated 444 strains belonging to 28 genera of halophiles from various environments around the world. The 16S rRNA gene sequences revealed that many of the isolated strains from geographically distant habitats having different environmental conditions, were closely related to each other, with some strains possessing 100% identical sequences. Organisms possessing survival mechanism such as spore formation are usually ubiquitous. The genus Halomonas is represented by potentially endemic strains and the ubiquitous H. variabilis, while spore-forming B. licheniformis showed cosmopolitan distribution. One potentially endemic (moderate endemicity that is regional and/or continental distribution strain was reported from Syowa station, East Antarctica, and Mario Zucchelli station, West Antarctica, which are geographically separated by 3000 km. Moreover, 15 strains having 100% similarity with B. licheniformis were considered cosmopolitans. The results of this work provide support for the middle-ground model that some microbes have moderate endemicity and others have cosmopolitan distribution. These results will contribute to a greater understanding of microbial biogeography with special emphasis on Antarctica.

  15. Bioenergetics of Continental Serpentinites

    Science.gov (United States)

    Cardace, D.; Meyer-Dombard, D. R.

    2011-12-01

    Serpentinization is the aqueous alteration of ultramafic (Fe- and Mg-rich) rocks, resulting in secondary mineral assemblages of serpentine, brucite, iron oxyhydroxides and magnetite, talc, and possibly carbonate and silica-rich veins and other minor phases-all depending on the evolving pressure-temperature-composition of the system. The abiotic evolution of hydrogen and possibly organic compounds via serpentinization (McCollom and Bach, 2009) highlights the relevance of this geologic process to carbon and energy sources for the deep biosphere. Serpentinization may fuel life over long stretches of geologic time, throughout the global seabed and in exposed, faulted peridotite blocks (as at Lost City Hydrothermal Field, Kelley et al., 2005), and in obducted oceanic mantle units in ophiolites (e.g., Tiago et al., 2004). Relatively little work has been published on life in continental serpentinite settings, though they likely host a unique resident microbiota. In this work, we systematically model the serpentinizing fluid as an environmental niche. Reported field data for high and moderate pH serpentinizing fluids were modeled from Cyprus, the Philippines, Oman, Northern California, New Caledonia, Yugoslavia, Portugal, Italy, Newfoundland Canada, New Zealand, and Turkey. Values for Gibbs Energy of reaction (ΔGr), kJ per mole of electrons transferred for a given metabolism, are calculated for each field site. Cases are considered both for (1) modest assumptions of 1 nanomolar hydrogen and 1 micromolar methane, based on unpublished data for a similar northern California field site (Cardace and Hoehler, in prep.) and (2) an upper estimate of 10 nanomolar hydrogen and 500 micromolar methane. We survey the feasibility of microbial metabolisms for key steps in the nitrogen cycle, oxidation of sulfur in pyrite, iron oxidation or reduction reactions, sulfate reduction coupled to hydrogen or methane oxidation, methane oxidation coupled to the reduction of oxygen, and

  16. A World Malaria Map: Plasmodium falciparum Endemicity in 2007

    Science.gov (United States)

    Hay, Simon I; Guerra, Carlos A; Gething, Peter W; Patil, Anand P; Tatem, Andrew J; Noor, Abdisalan M; Kabaria, Caroline W; Manh, Bui H; Elyazar, Iqbal R. F; Brooker, Simon; Smith, David L; Moyeed, Rana A; Snow, Robert W

    2009-01-01

    Background Efficient allocation of resources to intervene against malaria requires a detailed understanding of the contemporary spatial distribution of malaria risk. It is exactly 40 y since the last global map of malaria endemicity was published. This paper describes the generation of a new world map of Plasmodium falciparum malaria endemicity for the year 2007. Methods and Findings A total of 8,938 P. falciparum parasite rate (PfPR) surveys were identified using a variety of exhaustive search strategies. Of these, 7,953 passed strict data fidelity tests for inclusion into a global database of PfPR data, age-standardized to 2–10 y for endemicity mapping. A model-based geostatistical procedure was used to create a continuous surface of malaria endemicity within previously defined stable spatial limits of P. falciparum transmission. These procedures were implemented within a Bayesian statistical framework so that the uncertainty of these predictions could be evaluated robustly. The uncertainty was expressed as the probability of predicting correctly one of three endemicity classes; previously stratified to be an informative guide for malaria control. Population at risk estimates, adjusted for the transmission modifying effects of urbanization in Africa, were then derived with reference to human population surfaces in 2007. Of the 1.38 billion people at risk of stable P. falciparum malaria, 0.69 billion were found in Central and South East Asia (CSE Asia), 0.66 billion in Africa, Yemen, and Saudi Arabia (Africa+), and 0.04 billion in the Americas. All those exposed to stable risk in the Americas were in the lowest endemicity class (PfPR2−10 ≤ 5%). The vast majority (88%) of those living under stable risk in CSE Asia were also in this low endemicity class; a small remainder (11%) were in the intermediate endemicity class (PfPR2−10 > 5 to < 40%); and the remaining fraction (1%) in high endemicity (PfPR2−10 ≥ 40%) areas. High endemicity was widespread in the

  17. The continental lithosphere

    DEFF Research Database (Denmark)

    Artemieva, Irina

    2009-01-01

    The goal of the present study is to extract non-thermal signal from seismic tomography models in order to distinguish compositional variations in the continental lithosphere and to examine if geochemical and petrologic constraints on global-scale compositional variations in the mantle are consist......The goal of the present study is to extract non-thermal signal from seismic tomography models in order to distinguish compositional variations in the continental lithosphere and to examine if geochemical and petrologic constraints on global-scale compositional variations in the mantle...... are consistent with modern geophysical data. In the lithospheric mantle of the continents, seismic velocity variations of a non-thermal origin (calculated from global Vs seismic tomography data [Grand S.P., 2002. Mantle shear-wave tomography and the fate of subducted slabs. Philosophical Transactions...... of the Royal Society of London. Series A, 360, 2475–2491.; Shapiro N.M., Ritzwoller M.H. 2002. Monte-Carlo inversion for a global shear velocity model of the crust and upper mantle. Geophysical Journal International 151, 1–18.] and lithospheric temperatures [Artemieva I.M., Mooney W.D., 2001. Thermal structure...

  18. High-pressure metamorphic age and significance of eclogite-facies continental fragments associated with oceanic lithosphere in the Western Alps (Etirol-Levaz Slice, Valtournenche, Italy)

    Science.gov (United States)

    Fassmer, Kathrin; Obermüller, Gerrit; Nagel, Thorsten J.; Kirst, Frederik; Froitzheim, Nikolaus; Sandmann, Sascha; Miladinova, Irena; Fonseca, Raúl O. C.; Münker, Carsten

    2016-05-01

    The Etirol-Levaz Slice in the Penninic Alps (Valtournenche, Italy) is a piece of eclogite-facies continental basement sandwiched between two oceanic units, the blueschist-facies Combin Zone in the hanging wall and the eclogite-facies Zermatt-Saas Zone in the footwall. It has been interpreted as an extensional allochthon from the continental margin of Adria, emplaced onto ultramafic and mafic basement of the future Zermatt-Saas Zone by Jurassic, rifting-related detachment faulting, and later subducted together with the future Zermatt-Saas Zone. Alternatively, the Etirol-Levaz Slice could be derived from a different paleogeographic domain and be separated from the Zermatt-Saas Zone by an Alpine shear zone. We present Lu-Hf whole rock-garnet ages of two eclogite samples, one from the center of the unit and one from the border to the Zermatt-Saas Zone below. These data are accompanied by a new geological map of the Etirol-Levaz Slice and the surrounding area, as well as detailed petrology of these two samples. Assemblages, mineral compositions and garnet zoning in both samples indicate a clockwise PT-path and peak-metamorphic conditions of about 550-600 °C/20-25 kbar, similar to conditions proposed for the underlying Zermatt-Saas Zone. Prograde garnet ages of the two samples are 61.8 ± 1.8 Ma and 52.4 ± 2.1 Ma and reflect different timing of subduction. One of these is significantly older than published ages of eclogite-facies metamorphism in the Zermatt-Saas Zone and thus contradicts the hypothesis of Mesozoic emplacement. The occurrence of serpentinite and metagabbro bodies possibly derived from the Zermatt-Saas Zone inside the Etirol-Levaz Slice suggests that the latter is a tectonic composite. The basement slivers forming the Etirol-Levaz Slice and other continental fragments were subducted earlier than the Zermatt-Saas Zone, but nonetheless experienced similar pressure-temperature histories. Our results support the hypothesis that the Zermatt-Saas Zone and the

  19. Endemic Nephropathy Around the World.

    Science.gov (United States)

    Gifford, Fiona J; Gifford, Robert M; Eddleston, Michael; Dhaun, Neeraj

    2017-03-01

    There have been several global epidemics of chronic kidney disease of unknown etiology (CKDu). Some, such as Itai-Itai disease in Japan and Balkan endemic nephropathy, have been explained, whereas the etiology of others remains unclear. In countries such as Sri Lanka, El Salvador, Nicaragua, and India, CKDu is a major public health problem and causes significant morbidity and mortality. Despite their geographical separation, however, there are striking similarities between these endemic nephropathies. Young male agricultural workers who perform strenuous labor in extreme conditions are the worst affected. Patients remain asymptomatic until end-stage renal failure. Biomarkers of tubular injury are raised, and kidney biopsy shows chronic interstitial nephritis with associated tubular atrophy. In many of these places access to dialysis and transplantation is limited, leaving few treatment options. In this review we briefly describe the major historic endemic nephropathies. We then summarize the epidemiology, clinical features, histology and clinical course of CKDu in Mesoamerica, Sri Lanka, India, Egypt, and Tunisia. We draw comparisons between the proposed etiologies and supporting research. Recognition of the similarities may reinforce the international drive to establish causality and to effect prevention.

  20. Endemic Nephropathy Around the World

    Directory of Open Access Journals (Sweden)

    Fiona J. Gifford

    2017-03-01

    Full Text Available There have been several global epidemics of chronic kidney disease of unknown etiology (CKDu. Some, such as Itai-Itai disease in Japan and Balkan endemic nephropathy, have been explained, whereas the etiology of others remains unclear. In countries such as Sri Lanka, El Salvador, Nicaragua, and India, CKDu is a major public health problem and causes significant morbidity and mortality. Despite their geographical separation, however, there are striking similarities between these endemic nephropathies. Young male agricultural workers who perform strenuous labor in extreme conditions are the worst affected. Patients remain asymptomatic until end-stage renal failure. Biomarkers of tubular injury are raised, and kidney biopsy shows chronic interstitial nephritis with associated tubular atrophy. In many of these places access to dialysis and transplantation is limited, leaving few treatment options. In this review we briefly describe the major historic endemic nephropathies. We then summarize the epidemiology, clinical features, histology and clinical course of CKDu in Mesoamerica, Sri Lanka, India, Egypt, and Tunisia. We draw comparisons between the proposed etiologies and supporting research. Recognition of the similarities may reinforce the international drive to establish causality and to effect prevention.

  1. CARPATHIANS ENDEMIC TAXA IN ARGEŞ COUNTY

    Directory of Open Access Journals (Sweden)

    Valeriu Alexiu

    2013-12-01

    Full Text Available Endemic plant species are the biogeographic elements why use the delimitation of biogeographical regions. Their presence explains, in the context of identifying phyto-historical factors, distribution of species and certain distribution patterns. Endemic areas, with pronounced as the basic unit of biogeography, indicates those particular geographic region, both in the growth areas and the evolutionary biological processes of speciation.In this study we proposed the following objectives: knowing the list Carpathian endemic species and endemic centers present in Argeş, also, areas of endemism in the Carpathians Mountains of the Argeş County.

  2. Southeast continental shelf studies

    Energy Technology Data Exchange (ETDEWEB)

    Menzel, D.W.

    1979-02-12

    Research efforts on the southeast continental shelf currently describe the manner in which fluctuations in Gulf Stream motion influence biological and chemical processes. Current meter arrays are maintained in the Georgia Bight and in Onslow Bay to describe general circulation patterns and to identify forcing functions. biological studies describe processes affecting temporal and spatial variations on the shelf and have attempted to track the biological history of intruded Gulf Stream water masses. Chemical studies examine the influence of both physical and biological variables on the distribution and fate of trace elements. The current state of knowledge is reviewed, the hypotheses developed and are described, a rationale for testing these hypotheses is given. 1 figure, 1 table.

  3. NSF Continental Lithosphere Program

    Science.gov (United States)

    Mayhew, Michael; MacGregor, Ian

    For several months the Continental Lithosphere Program (CL) of the National Science Foundation has been subject to a major review. The process was stimulated by a series of budget setbacks over the past few years. Although Presidential budget requests have been very favorable for the Division of Earth Sciences (EAR), and there has been strong support within the National Science Foundation and Congress, actual appropriations by Congress have been disappointing.In each year the final allocation to EAR has been affected by external factors beyond the control of the Foundation. In the four fiscal years from 1986 through 1989 the factors include reductions tied to the Gramm-Rudman deficit reduction measures, congressional reaction to the October 1987 stock market crash, and two years of protection for the Ocean Sciences part of the NSF budget that was paid for from the budgets of the Atmospheric and Earth Sciences divisions.

  4. Mapping internal connectivity through human migration in malaria endemic countries.

    Science.gov (United States)

    Sorichetta, Alessandro; Bird, Tom J; Ruktanonchai, Nick W; Zu Erbach-Schoenberg, Elisabeth; Pezzulo, Carla; Tejedor, Natalia; Waldock, Ian C; Sadler, Jason D; Garcia, Andres J; Sedda, Luigi; Tatem, Andrew J

    2016-08-16

    Human mobility continues to increase in terms of volumes and reach, producing growing global connectivity. This connectivity hampers efforts to eliminate infectious diseases such as malaria through reintroductions of pathogens, and thus accounting for it becomes important in designing global, continental, regional, and national strategies. Recent works have shown that census-derived migration data provides a good proxy for internal connectivity, in terms of relative strengths of movement between administrative units, across temporal scales. To support global malaria eradication strategy efforts, here we describe the construction of an open access archive of estimated internal migration flows in endemic countries built through pooling of census microdata. These connectivity datasets, described here along with the approaches and methods used to create and validate them, are available both through the WorldPop website and the WorldPop Dataverse Repository.

  5. Utility of T-Cell Interferon-γ Release Assays for Etiological Diagnosis of Classic Fever of Unknown Origin in a High Tuberculosis Endemic Area--a pilot prospective cohort.

    Science.gov (United States)

    Shi, Xiaochun; Zhang, Lifan; Zhang, Yueqiu; Zhou, Baotong; Liu, Xiaoqing

    2016-01-01

    Tuberculosis (TB), especially extrapulmonary TB is still the leading cause of fever of unknown origin (FUO) in China. However, diagnosis of TB still remains a challenge. The aim of this study was to evaluate the diagnostic value of T-SPOT.TB for etiological diagnosis of classic FUO in adult patients in a high TB endemic area. We prospectively enrolled patients presenting with classic FUO in a tertiary referral hospital in Beijing, China, to investigate the diagnostic sensitivity, specificity, predictive values and likelihood ratio of T-SPOT.TB. Clinical assessment and T-SPOT.TB were performed. Test results were compared with the final confirmed clinical diagnosis. 387 hospitalized patients (male n = 194, female n = 193; median age 46 (range 29-59) yrs) with classic FUO were prospectively enrolled into this study. These FUOs were caused by infection (n = 158, 40.8%), connective tissue disease (n = 82, 21.2%), malignancy (n = 41, 10.6%) and miscellaneous other causes (n = 31, 8.0%), and no cause was determined in 75 (19.4%) patients. 68 cases were diagnosed as active TB eventually. The sensitivity of T-SPOT.TB for the diagnosis of active TB was 70.6% (95%CI 58.9-80.1%), while specificity was 84.4% (95%CI 79.4-88.4%), positive predictive value was 55.8% (95%CI 45.3-65.8%), negative predictive value was 91.2% (95%CI 86.7-94.2%). Among these 68 active TB patients, 12 cases were culture or histology confirmed (11 cases with positive T-SPOT.TB, sensitivity was 91.7%) and 56 cases were clinically diagnosed (37 cases with positive T-SPOT.TB, sensitivity was 66.1%); 14 cases were pulmonary TB (13 cases with positive T-SPOT.TB, sensitivity was 92.9%) and 54 cases were extrapulmonary TB (35 cases with positive T-SPOT.TB, sensitivity was 64.8%). For patients presenting with classic FUO in this TB endemic setting, T-SPOT.TB appears valuable for excluding active TB, with a high negative predictive value.

  6. Utility of T-Cell Interferon-γ Release Assays for Etiological Diagnosis of Classic Fever of Unknown Origin in a High Tuberculosis Endemic Area--a pilot prospective cohort.

    Directory of Open Access Journals (Sweden)

    Xiaochun Shi

    Full Text Available Tuberculosis (TB, especially extrapulmonary TB is still the leading cause of fever of unknown origin (FUO in China. However, diagnosis of TB still remains a challenge. The aim of this study was to evaluate the diagnostic value of T-SPOT.TB for etiological diagnosis of classic FUO in adult patients in a high TB endemic area.We prospectively enrolled patients presenting with classic FUO in a tertiary referral hospital in Beijing, China, to investigate the diagnostic sensitivity, specificity, predictive values and likelihood ratio of T-SPOT.TB. Clinical assessment and T-SPOT.TB were performed. Test results were compared with the final confirmed clinical diagnosis.387 hospitalized patients (male n = 194, female n = 193; median age 46 (range 29-59 yrs with classic FUO were prospectively enrolled into this study. These FUOs were caused by infection (n = 158, 40.8%, connective tissue disease (n = 82, 21.2%, malignancy (n = 41, 10.6% and miscellaneous other causes (n = 31, 8.0%, and no cause was determined in 75 (19.4% patients. 68 cases were diagnosed as active TB eventually. The sensitivity of T-SPOT.TB for the diagnosis of active TB was 70.6% (95%CI 58.9-80.1%, while specificity was 84.4% (95%CI 79.4-88.4%, positive predictive value was 55.8% (95%CI 45.3-65.8%, negative predictive value was 91.2% (95%CI 86.7-94.2%. Among these 68 active TB patients, 12 cases were culture or histology confirmed (11 cases with positive T-SPOT.TB, sensitivity was 91.7% and 56 cases were clinically diagnosed (37 cases with positive T-SPOT.TB, sensitivity was 66.1%; 14 cases were pulmonary TB (13 cases with positive T-SPOT.TB, sensitivity was 92.9% and 54 cases were extrapulmonary TB (35 cases with positive T-SPOT.TB, sensitivity was 64.8%.For patients presenting with classic FUO in this TB endemic setting, T-SPOT.TB appears valuable for excluding active TB, with a high negative predictive value.

  7. Making continental crust: The sanukitoid connection

    Institute of Scientific and Technical Information of China (English)

    Yoshiyuki TATSUMI

    2008-01-01

    The average continental crust possesses intermediate compositions that typify arc magmatism and as a result it is believed to have been created at ancient convergent plate boundaries. One possible mechanism for intermediate continental crust formation is the direct production of andesitic melts in the upper mantle. Sanukitoids, which characterize the Setouchi volcanic belt, SW Japan, include unusually high-Mg andesites (HMA). They were generated by slab melting and subsequent melt-mantle interactions under unusual tectonic settings such as where warm lithosphere subducts into hot upper mantle. Such conditions would have existed in the Archean. Hydrous HMA magmas are likely to have solidified within the crust to form HMA plutons, which were then remelted to produce differentiated sanukitoids. At present, generation and differentiation of HMA magmas may be taking place in the Izu-Bonin-Mariana arc-trench system (IBM), because (1) HMA magmatism characterizes the initial stages of the iBM evolution and (2) the IBM middle crust exhibits Vp identical to that of the bulk continental crust. Vp estimates for plutonic rocks with HMA compositions support this. However tonalitic composition for middle-crust-forming rocks cannot be ruled out, suggesting an alternative possibility that the continental crust has been created by differentiation of mantle-derived basaltic magmas.

  8. Sacred groves of north Malabar: treasure trove of endemic and rare medicinal plants

    Directory of Open Access Journals (Sweden)

    K. Subrahmanya Prasad

    2011-01-01

    Sacred groves are one of the finest examples of traditional in situ conservation practices and act as treasure house of endemic, endangered and rare plants. Endemic species of any geographical region, throw light on the biogeography of the area, areas of extinction and evolution of the flora. Twelve famous sacred groves of north Malabar region of Kerala were selected for study. Studies were aimed at the documentation of floristic diversity with special reference to endemic as well as RET medicinal plants and to know threats to them. Present inventory accounted for a total of 99 endemic angiosperms, of which 28 qualified for RET categories. Their role in germplasm conservation is evident from the fact that not a single plant is common to the groves studied and restriction of 47 endemic plants to any one of the grove. There are 59 endemic plants, of which 18 belong to RET category are in high demand due to their medicinal properties. Medicinal plant diversity varies from a minimum of 65% to a maximum of 91% while that of endemic plants ranges from 11% in Andallur to 18% in Edayilakkad. Present study revealed the endemic plant diversity of these groves and also their role in the conserving germplasms of wild yam, figs, pepper, mango and a variety of endemic medicinal plants. Like other groves of Kerala, these are also facing the threat of extinction from increasing anthropogenic activities and there is an urgent need of complete protection and public awareness for the existence of these near-climax communities.

  9. Association of the level of IFN-γ produced by T cells in response to Mycobacterium tuberculosis-specific antigens with the size of skin test indurations among individuals with latent tuberculosis in a highly tuberculosis-endemic setting.

    Science.gov (United States)

    Legesse, Mengistu; Ameni, Gobena; Mamo, Gezahegne; Medhin, Girmay; Bjune, Gunnar; Abebe, Fekadu

    2012-02-01

    There is growing evidence showing the potential of T-cell-based gamma interferon (IFN-γ) release assays (IGRAs) for predicting the risk of progression of Mycobacterium tuberculosis (Mtb) infection, though there is little information from tuberculosis (TB)-endemic settings. In this study, we assessed the association between the level of IFN-γ produced by T cells in response to Mtb-specific antigens and the size of skin test indurations in 505 adult individuals who were screened for latent tuberculosis infection (LTBI) using the QuantiFERON-TB Gold In Tube (QFTGIT) assay and tuberculin skin test (TST). There was a strong positive correlation between the level of IFN-γ induced by the specific antigens and the diameter of the skin indurations (Spearman's rho = 0.6, P skin test indurations was significantly associated with the mean level of IFN-γ [coefficient, 0.65; 95% confidence interval (CI), 0.47 to 0.82, P skin test indurations ≥ 10 mm were 6.82 times more likely than individuals who had skin test indurations < 10 mm to have high levels of IFN-γ (i.e. positive QFTGIT result) (adjusted odd ratio = 6.82; 95% CI, 3.67 to 12.69, P < 0.001). In conclusion, the results of this study could provide indirect evidence for the prognostic use of the QFTGIT assay for progression of Mtb infection, though prospective follow-up studies are needed to provide direct evidence.

  10. Palaeomagnetism and the continental crust

    Energy Technology Data Exchange (ETDEWEB)

    Piper, J.D.A.

    1987-01-01

    This book is an introduction to palaeomagnetism offering treatment of theory and practice. It analyzes the palaeomagnetic record over the whole of geological time, from the Archaean to the Cenozoic, and goes on to examine the impact of past geometries and movements of the continental crust at each geological stage. Topics covered include theory of rock and mineral magnetism, field and laboratory methods, growth and consolidation of the continental crust in Archaean and Proterozoic times, Palaeozoic palaeomagnetism and the formation of Pangaea, the geomagnetic fields, continental movements, configurations and mantle convection.

  11. The continental record and the generation of continental crust

    OpenAIRE

    Cawood, Peter Anthony; Hawkesworth, Chris; Dhuime, Bruno Philippe Marcel

    2013-01-01

    Continental crust is the archive of Earth history. The spatial and temporal distribution of Earth's record of rock units and events is heterogeneous; for example, ages of igneous crystallization, metamorphism, continental margins, mineralization, and seawater and atmospheric proxies are distributed about a series of peaks and troughs. This distribution reflects the different preservation potential of rocks generated in different tectonic settings, rather than fundamental pulses of activity, a...

  12. Ecology, distribution, and predictive occurrence modeling of Palmers chipmunk (Tamias palmeri): a high-elevation small mammal endemic to the Spring Mountains in southern Nevada, USA

    Science.gov (United States)

    Lowrey, Chris E.; Longshore, Kathleen; Riddle, Brett R.; Mantooth, Stacy

    2016-01-01

    Although montane sky islands surrounded by desert scrub and shrub steppe comprise a large part of the biological diversity of the Basin and Range Province of southwestern North America, comprehensive ecological and population demographic studies for high-elevation small mammals within these areas are rare. Here, we examine the ecology and population parameters of the Palmer’s chipmunk (Tamias palmeri) in the Spring Mountains of southern Nevada, and present a predictive GIS-based distribution and probability of occurrence model at both home range and geographic spatial scales. Logistic regression analyses and Akaike Information Criterion model selection found variables of forest type, slope, and distance to water sources as predictive of chipmunk occurrence at the geographic scale. At the home range scale, increasing population density, decreasing overstory canopy cover, and decreasing understory canopy cover contributed to increased survival rates.

  13. Spontaneous Subdural Empyema Following a High-Parasitemia Falciparum Infection in a 58-Year-Old Female From a Malaria-Endemic Region

    Directory of Open Access Journals (Sweden)

    Pedro Pallangyo MD, MPH

    2016-08-01

    Full Text Available Malaria remains a significant public health problem of the tropical world. Falciparum malaria is most prevalent in the sub-Saharan African region, which harbors about 90% of all malaria cases and fatalities globally. Infection by the falciparum species often manifests with a spectrum of multi-organ complications (eg, cerebral malaria, some of which are life-threatening. Spontaneous subdural empyema is a very rare complication of cerebral malaria that portends a very poor prognosis unless diagnosed and treated promptly. We report a case of spontaneous subdural empyema in a 58-year-old woman from Tanzania who presented with high-grade fever, decreased urine output, and altered sensorium.

  14. Dynamics of continental accretion.

    Science.gov (United States)

    Moresi, L; Betts, P G; Miller, M S; Cayley, R A

    2014-04-10

    Subduction zones become congested when they try to consume buoyant, exotic crust. The accretionary mountain belts (orogens) that form at these convergent plate margins have been the principal sites of lateral continental growth through Earth's history. Modern examples of accretionary margins are the North American Cordilleras and southwest Pacific subduction zones. The geologic record contains abundant accretionary orogens, such as the Tasmanides, along the eastern margin of the supercontinent Gondwana, and the Altaïdes, which formed on the southern margin of Laurasia. In modern and ancient examples of long-lived accretionary orogens, the overriding plate is subjected to episodes of crustal extension and back-arc basin development, often related to subduction rollback and transient episodes of orogenesis and crustal shortening, coincident with accretion of exotic crust. Here we present three-dimensional dynamic models that show how accretionary margins evolve from the initial collision, through a period of plate margin instability, to re-establishment of a stable convergent margin. The models illustrate how significant curvature of the orogenic system develops, as well as the mechanism for tectonic escape of the back-arc region. The complexity of the morphology and the evolution of the system are caused by lateral rollback of a tightly arcuate trench migrating parallel to the plate boundary and orthogonally to the convergence direction. We find geological and geophysical evidence for this process in the Tasmanides of eastern Australia, and infer that this is a recurrent and global phenomenon.

  15. Population viability of the narrow endemic Helianthemum juliae (CISTACEAE) in relation to climate variability

    NARCIS (Netherlands)

    Marrero-Gomez, M.V.; Oostermeijer, J.G.B.; Carque-Alamo, E.; Banares-Baudet, A.

    2007-01-01

    Narrow endemic plants are highly vulnerable to extinction as a result of human disturbance and climate change. We investigated the factors affecting the population viability of Helianthemum juliae, a perennial plant endemic to the Teide National Park on Tenerife, Canary Islands. One population was

  16. Proactive conservation management of an island-endemic bird species in the face of global change

    Science.gov (United States)

    Morrison, S.A.; Sillett, T. Scott; Ghalambor, Cameron K.; Fitzpatrick, J.W.; Graber, D.M.; Bakker, V.J.; Bowman, R.; Collins, C.T.; Collins, P.W.; Delaney, K.S.; Doak, D.F.; Koenig, W.D.; Laughrin, L.; Lieberman, A.A.; Marzluff, J.M.; Reynolds, M.D.; Scott, J.M.; Stallcup, J.A.; Vickers, W.; Boyce, W.M.

    2011-01-01

    Biodiversity conservation in an era of global change and scarce funding benefits from approaches that simultaneously solve multiple problems. Here, we discuss conservation management of the island scrub-jay (Aphelocoma insularis), the only island-endemic passerine species in the continental United States, which is currently restricted to 250-square-kilometer Santa Cruz Island, California. Although the species is not listed as threatened by state or federal agencies, its viability is nonetheless threatened on multiple fronts. We discuss management actions that could reduce extinction risk, including vaccination, captive propagation, biosecurity measures, and establishing a second free-living population on a neighboring island. Establishing a second population on Santa Rosa Island may have the added benefit of accelerating the restoration and enhancing the resilience of that island's currently highly degraded ecosystem. The proactive management framework for island scrub-jays presented here illustrates how strategies for species protection, ecosystem restoration, and adaptation to and mitigation of climate change can converge into an integrated solution. ?? 2011 by American Institute of Biological Sciences. All rights reserved.

  17. Late endemic syphilis: case report of bejel with gummatous laryngitis.

    OpenAIRE

    Pace, J. L.; Csonka, G. W.

    1988-01-01

    An elderly Bedouin woman originally thought, on clinical and histological grounds, to have tuberculosis of the larynx was found to have gummatous laryngitis due to late endemic syphilis (bejel). This disease is highly prevalent in the Bedouin tribes of the Middle East. Doctors dealing with Arab patients, either in the Middle East or elsewhere, should be aware of this possibility.

  18. 3.30 Ga high-silica intraplate volcanic-plutonic system of the Gavião Block, São Francisco Craton, Brazil: Evidence of an intracontinental rift following the creation of insulating continental crust

    Science.gov (United States)

    Zincone, Stefano A.; Oliveira, Elson P.; Laurent, Oscar; Zhang, Hong; Zhai, Mingguo

    2016-12-01

    High-silica rhyolites having U-Pb zircon ages of 3303 ± 11 Ma occur along the eastern border of the Gavião Block (Brazil) associated with the Contendas-Mirante and Mundo Novo supracrustal belts. Unlike many Archean greenstone sequences, they are not interlayered with mafic to intermediate units. Instead, they belong to an inter-related plutonic-volcanic system, together with granitic massifs having similar zircon crystallization ages of ca. 3293 ± 3 Ma and 3328 ± 3 Ma and plotting along the same geochemical trends as the rhyolites. The rhyolites show well-preserved primary volcanic features such as magma flow textures and euhedral phenocrysts. High emplacement temperatures are indicated by petrographic evidence (β-quartz phenocrysts), zircon saturation temperatures (915-820 °C) and geochemical data, especially high SiO2 (74-79 wt.%) together with elevated Fe2O3(T) ( 3 wt.%), MgO (0.5-1.5 wt.%) and low Al2O3 (extraction and eruption of highly silicic residual liquid formed by crystallization of granitic magma in a relatively shallow (< 10 km) reservoir, now represented by the granite massifs. The granite magma was formed by melting or differentiation of material similar to the diorite gneiss that occurs regionally. The 3.30 Ga volcanic-plutonic systems formed after a period of crustal growth and stabilization of a thick continental lithosphere, represented by massive 3.40-3.33 Ga TTG and medium to high-K calk-alkaline magmatism in the Gavião Block. The 3.30 Ga-old rhyolites and granites would therefore have formed in an intracontinental tectonic setting after the formation and stabilization of new continental crust, and accordingly would represent the first stages of rifting and continental break-up. Intraplate magmatism and intracrustal differentiation processes took place on Earth at 3.3 Ga and produced magmas that were distinct from Archean TTGs, questioning the reliability (or at least the uniqueness) of "intraplate models" to explain the origin of the

  19. Continental United States Hurricane Strikes

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Continental U.S. Hurricane Strikes Poster is our most popular poster which is updated annually. The poster includes all hurricanes that affected the U.S. since...

  20. Endemism analysis of Neotropical Pentatomidae (Hemiptera, Heteroptera

    Directory of Open Access Journals (Sweden)

    Augusto Ferrari

    2010-12-01

    Full Text Available The definition of areas of endemism is central to studies of historical biogeography, and their interrelationships are fundamental questions. Consistent hypotheses for the evolution of Pentatomidae in the Neotropical region depend on the accuracy of the units employed in the analyses, which in the case of studies of historical biogeography, may be areas of endemism. In this study, the distribution patterns of 222 species, belonging to 14 Pentatomidae (Hemiptera genera, predominantly neotropical, were studied with the Analysis of Endemicity (NDM to identify possible areas of endemism and to correlate them to previously delimited areas. The search by areas of endemism was carried out using grid-cell units of 2.5° and 5° latitude-longitude. The analysis based on groupings of grid-cells of 2.5° of latitude-longitude allowed the identification of 51 areas of endemism, the consensus of these areas resulted in four clusters of grid-cells. The second analysis, with grid-cells units of 5° latitude-longitude, resulted in 109 areas of endemism. The flexible consensus employed resulted in 17 areas of endemism. The analyses were sensitive to the identification of areas of endemism in different scales in the Atlantic Forest. The Amazonian region was identified as a single area in the area of consensus, and its southeastern portion shares elements with the Chacoan and Paraná subregions. The distribution data of the taxa studied, with different units of analysis, did not allow the identification of individual areas of endemism for the Cerrado and Caatinga. The areas of endemism identified here should be seen as primary biogeographic hypotheses.

  1. The mammalian faunas endemic to the Cerrado and the Caatinga

    Science.gov (United States)

    Gutiérrez, Eliécer E.; Marinho-Filho, Jader

    2017-01-01

    Abstract We undertook a comprehensive, critical review of literature concerning the distribution, conservation status, and taxonomy of species of mammals endemic to the Cerrado and the Caatinga, the two largest biomes of the South American Dry-Diagonal. We present species accounts and lists of species, which we built with criteria that, in our opinion, yielded results with increased scientific rigor relative to previously published lists – e.g., excluding nominal taxa whose statuses as species have been claimed only on the basis of unpublished data, incomplete taxonomic work, or weak evidence. For various taxa, we provided arguments regarding species distributions, conservation and taxonomic statuses previously lacking in the literature. Two major findings are worth highlighting. First, we unveil the existence of a group of species endemic to both the Cerrado and the Caatinga (i.e., present in both biomes and absent in all other biomes). From the biogeographic point of view, this group, herein referred to as Caatinga-Cerrado endemics, deserves attention as a unit – just as in case of the Caatinga-only and the Cerrado-only endemics. We present preliminary hypotheses on the origin of these three endemic faunas (Cerrado-only, Caatinga-only, and Caatinga-Cerrado endemics). Secondly, we discovered that a substantial portion of the endemic mammalian faunas of the Caatinga and the Cerrado faces risks of extinction that are unrecognized in the highly influential Red List of Threatened Species published by the International Union for Conservation of Nature (IUCN). “Data deficient” is a category that misrepresents the real risks of extinction of these species considering that (a) some of these species are known only from a handful of specimens collected in a single or a few localities long ago; (b) the Cerrado and the Caatinga have been sufficiently sampled to guarantee collection of additional specimens of these species if they were abundant; (c) natural habitats of

  2. The mammalian faunas endemic to the Cerrado and the Caatinga.

    Science.gov (United States)

    Gutiérrez, Eliécer E; Marinho-Filho, Jader

    2017-01-01

    We undertook a comprehensive, critical review of literature concerning the distribution, conservation status, and taxonomy of species of mammals endemic to the Cerrado and the Caatinga, the two largest biomes of the South American Dry-Diagonal. We present species accounts and lists of species, which we built with criteria that, in our opinion, yielded results with increased scientific rigor relative to previously published lists - e.g., excluding nominal taxa whose statuses as species have been claimed only on the basis of unpublished data, incomplete taxonomic work, or weak evidence. For various taxa, we provided arguments regarding species distributions, conservation and taxonomic statuses previously lacking in the literature. Two major findings are worth highlighting. First, we unveil the existence of a group of species endemic to both the Cerrado and the Caatinga (i.e., present in both biomes and absent in all other biomes). From the biogeographic point of view, this group, herein referred to as Caatinga-Cerrado endemics, deserves attention as a unit - just as in case of the Caatinga-only and the Cerrado-only endemics. We present preliminary hypotheses on the origin of these three endemic faunas (Cerrado-only, Caatinga-only, and Caatinga-Cerrado endemics). Secondly, we discovered that a substantial portion of the endemic mammalian faunas of the Caatinga and the Cerrado faces risks of extinction that are unrecognized in the highly influential Red List of Threatened Species published by the International Union for Conservation of Nature (IUCN). "Data deficient" is a category that misrepresents the real risks of extinction of these species considering that (a) some of these species are known only from a handful of specimens collected in a single or a few localities long ago; (b) the Cerrado and the Caatinga have been sufficiently sampled to guarantee collection of additional specimens of these species if they were abundant; (c) natural habitats of the Cerrado and

  3. Comparative phylogeography of endemic Azorean arthropods

    DEFF Research Database (Denmark)

    Parmakelis, Aristeidis; Rigal, François; Mourikis, Thanos

    2015-01-01

    Background: For a remote oceanic archipelago of up to 8 Myr age, the Azores have a comparatively low level of endemism. We present an analysis of phylogeographic patterns of endemic Azorean island arthropods aimed at testing patterns of diversification in relation to the ontogeny of the archipelago...

  4. Malaria in Brazil: what happens outside the Amazonian endemic region.

    Science.gov (United States)

    de Pina-Costa, Anielle; Brasil, Patrícia; Di Santi, Sílvia Maria; de Araujo, Mariana Pereira; Suárez-Mutis, Martha Cecilia; Santelli, Ana Carolina Faria e Silva; Oliveira-Ferreira, Joseli; Lourenço-de-Oliveira, Ricardo; Daniel-Ribeiro, Cláudio Tadeu

    2014-08-01

    Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation's territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation's malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013). The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon) or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex). The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites that seem to be (or

  5. Malaria in Brazil: what happens outside the Amazonian endemic region

    Directory of Open Access Journals (Sweden)

    Anielle de Pina-Costa

    2014-08-01

    Full Text Available Brazil, a country of continental proportions, presents three profiles of malaria transmission. The first and most important numerically, occurs inside the Amazon. The Amazon accounts for approximately 60% of the nation’s territory and approximately 13% of the Brazilian population. This region hosts 99.5% of the nation’s malaria cases, which are predominantly caused by Plasmodium vivax (i.e., 82% of cases in 2013. The second involves imported malaria, which corresponds to malaria cases acquired outside the region where the individuals live or the diagnosis was made. These cases are imported from endemic regions of Brazil (i.e., the Amazon or from other countries in South and Central America, Africa and Asia. Imported malaria comprised 89% of the cases found outside the area of active transmission in Brazil in 2013. These cases highlight an important question with respect to both therapeutic and epidemiological issues because patients, especially those with falciparum malaria, arriving in a region where the health professionals may not have experience with the clinical manifestations of malaria and its diagnosis could suffer dramatic consequences associated with a potential delay in treatment. Additionally, because the Anopheles vectors exist in most of the country, even a single case of malaria, if not diagnosed and treated immediately, may result in introduced cases, causing outbreaks and even introducing or reintroducing the disease to a non-endemic, receptive region. Cases introduced outside the Amazon usually occur in areas in which malaria was formerly endemic and are transmitted by competent vectors belonging to the subgenus Nyssorhynchus (i.e., Anopheles darlingi, Anopheles aquasalis and species of the Albitarsis complex. The third type of transmission accounts for only 0.05% of all cases and is caused by autochthonous malaria in the Atlantic Forest, located primarily along the southeastern Atlantic Coast. They are caused by parasites

  6. Prolonged colonisation with Escherichia coli O25:ST131 versus other extended-spectrum beta-lactamase-producing E. coli in a long-term care facility with high endemic level of rectal colonisation, the Netherlands, 2013 to 2014.

    Science.gov (United States)

    Overdevest, Ilse; Haverkate, Manon; Veenemans, Jacobien; Hendriks, Yvonne; Verhulst, Carlo; Mulders, Ans; Couprie, Willemijn; Bootsma, Martin; Johnson, James; Kluytmans, Jan

    2016-10-20

    The extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli clone ST131 (ESBL-ST131) has spread in healthcare settings worldwide. The reasons for its successful spread are unknown, but might include more effective transmission and/or longer persistence. We evaluated the colonisation dynamics of ESBL-producing E. coli (ESBL-EC), including ESBL-ST131, in a long-term care facility (LTCF) with an unusually high prevalence of rectal ESBL-EC colonisation. During a 14-month period, rectal or faecal samples were obtained from 296 residents during six repetitive prevalence surveys, using ESBL-selective culture. Transmission rates, reproduction numbers, and durations of colonisation were compared for ESBL-ST131 vs other ESBL-EC. Furthermore, the likely time required for ESBL-ST131 to disappear from the LTCF was estimated. Over time, the endemic level of ESBL-ST131 remained elevated whereas other ESBL-EC returned to low-level prevalence, despite comparable transmission rates. Survival analysis showed a half-life of 13 months for ESBL-ST131 carriage, vs two to three months for other ESBL-EC (p < 0.001). Per-admission reproduction numbers were 0.66 for ESBL-ST131 vs 0.56 for other ESBL-EC, predicting a mean time of three to four years for ESBL-ST131 to disappear from the LTCF under current conditions. Transmission rates were comparable for ESBL-ST131 vs other ESBL-EC. Prolonged rectal carriage explained the persistence of ESBL-ST131 in the LTCF.

  7. Towards eliminating malaria in high endemic countries: the roles of community health workers and related cadres and their challenges in integrated community case management for malaria: a systematic review.

    Science.gov (United States)

    Sunguya, Bruno F; Mlunde, Linda B; Ayer, Rakesh; Jimba, Masamine

    2017-01-03

    Human resource for health crisis has impaired global efforts against malaria in highly endemic countries. To address this, the World Health Organization (WHO) recommended scaling-up of community health workers (CHWs) and related cadres owing to their documented success in malaria and other disease prevention and management. Evidence is inconsistent on the roles and challenges they encounter in malaria interventions. This systematic review aims to summarize evidence on roles and challenges of CHWs and related cadres in integrated community case management for malaria (iCCM). This systematic review retrieved evidence from PubMed, CINAHL, ISI Web of Knowledge, and WHO regional databases. Terms extracted from the Boolean phrase used for PubMed were also used in other databases. The review included studies with Randomized Control Trial, Quasi-experimental, Pre-post interventional, Longitudinal and cohort, Cross-sectional, Case study, and Secondary data analysis. Because of heterogeneity, only narrative synthesis was conducted for this review. A total of 66 articles were eligible for analysis out of 1380 studies retrieved. CHWs and related cadre roles in malaria interventions included: malaria case management, prevention including health surveillance and health promotion specific to malaria. Despite their documented success, CHWs and related cadres succumb to health system challenges. These are poor and unsustainable finance for iCCM, workforce related challenges, lack of and unsustainable supply of medicines and diagnostics, lack of information and research, service delivery and leadership challenges. Community health workers and related cadres had important preventive, case management and promotive roles in malaria interventions. To enable their effective integration into the health systems, the identified challenges should be addressed. They include: introducing sustainable financing on iCCM programmes, tailoring their training to address the identified gaps

  8. Stratigraphic Modelling of Continental Rifting

    Science.gov (United States)

    Mondy, Luke; Duclaux, Guillaume; Salles, Tristan; Thomas, Charmaine; Rey, Patrice

    2013-04-01

    Interlinks between deformation and sedimentation have long been recognised as an important factor in the evolution of continental rifts and basins development. However, determining the relative impact of tectonic and climatic forcing on the dynamics of these systems remains a major challenge. This problem in part derives from a lack of modelling tools capable of simulated high detailed surface processes within a large scale (spatially and temporally) tectonic setting. To overcome this issue an innovative framework has been designed using two existing numerical forward modelling codes: Underworld, capable of simulating 3D self-consistent tectonic and thermal lithospheric processes, and Tellus, a forward stratigraphic and geomorphic modelling framework dedicated to simulating highly detailed surface dynamics. The coupling framework enables Tellus to use Underworld outputs as internal and boundary conditions, thereby simulating the stratigraphic and geomorphic evolution of a realistic, active tectonic setting. The resulting models can provide high-resolution data on the stratigraphic record, grain-size variations, sediment provenance, fluvial hydrometric, and landscape evolution. Here we illustrate a one-way coupling method between active tectonics and surface processes in an example of 3D oblique rifting. Our coupled model enables us to visualise the distribution of sediment sources and sinks, and their evolution through time. From this we can extract and analyse at each simulation timestep the stratigraphic record anywhere within the model domain. We find that even from a generic oblique rift model, complex fluvial-deltaic and basin filling dynamics emerge. By isolating the tectonic activity from landscape dynamics with this one-way coupling, we are able to investigate the influence of changes in climate or geomorphic parameters on the sedimentary and landscape record. These impacts can be quantified in part via model post-processing to derive both instantaneous and

  9. [Schistosomiasis endemic in Burkina Faso].

    Science.gov (United States)

    Poda, J N; Traoré, A; Sondo, B K

    2004-02-01

    Burkina Faso, through the works of many teams of the OCCGE based in Bobo-Dioulasso, has signi-ficant data on several tropical endemics of which schistosomiasis. With the complementary works, it appears to be possible to establish a distribution of the schistosomiasis which reveals its importance. It will be the first stage of the planned national control program. The parasitologic data-gathering which covers the period of 1951 to 2000, used all the standard techniques. It is about Kato-Kartz and MIF for the intestinal schistosomiasis, centrifugation, filtration, serology reagent strips, macroscopy of urines and echography of the urinary system for the urinary schistosomiasis. All the eleven medical areas of the country have many sites submitted to parasitologic investigation. As regard the distribution of the two parasites involved with man (Schistosoma haematobium and S. mansoni), the data of prevalence (1% to 100%) and their distribution confirm their endemicity and the focal transmission. S. mansoni is located in eight medical areas particularly in the South and the West. S. haematobium is present in all the eleven medical areas of the country. In hydraulic planning as Sourou where the prevalences went from 23% to 70% for S. haematobium and from 0% to 69% for S. mansoni between 1987 and 1998. The situation requires a continuous monitoring. The spatial distribution of the six species of intermediate hosts shows that Bulinus truncatus and B. senegalensis Soudano-Sahelian species are present in all the ecological zones. B. globosus and Biomphalaria pfeifferi meet preferentially in the southern half of the country which reinforces the observation according to which the 14th northern parallel is often considered as the limit of septentrional extension of these two species. The other species Bulinus forskalii and B umbilicatus could have preference areas. All the species show a certain affinity with a type of biotope. The rarity and temporary aquatic systems lead to a

  10. 76 FR 2919 - Outer Continental Shelf Official Protraction Diagram and Supplemental Official Outer Continental...

    Science.gov (United States)

    2011-01-18

    ... Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf Official Protraction Diagram and Supplemental Official Outer Continental Shelf Block Diagrams AGENCY: Bureau of Ocean... American Datum of 1983 (NAD 83) Outer Continental Shelf Official Protraction Diagram and...

  11. [Endemic situation and control progress of taeniasis in western China].

    Science.gov (United States)

    Long, Chang-Ping; Qian, Ying-Jun; Li, Tiao-Ying; Fu, Qing; Wang, Qiang; Xiao, Ning

    2014-06-01

    Taeniasis, caused by Taenia species, is one of the common zoonoses in China, particularly in the western region of China. Up to now, not enough attention has been given in the high prevalence and high burden of the diseases. In order to study the endemic patterns and control strategies of taeniasis, a series of epidemiological investigations, molecular researches and pilot control activities have been conducted in recent years. This paper reviews the relevant publications in taeniasis research over the last 10 years.

  12. Environmental Monitoring of Endemic Cholera

    Science.gov (United States)

    ElNemr, W.; Jutla, A. S.; Constantin de Magny, G.; Hasan, N. A.; Islam, M.; Sack, R.; Huq, A.; Hashem, F.; Colwell, R.

    2012-12-01

    Cholera remains a major public health threat. Since Vibrio cholerae, the causative agent of the disease, is autochthonous to riverine, estuarine, and coastal waters, it is unlikely the bacteria can be eradicated from its natural habitat. Prediction of disease, in conjunction with preventive vaccination can reduce the prevalence rate of a disease. Understanding the influence of environmental parameters on growth and proliferation of bacteria is an essential first step in developing prediction methods for outbreaks. Large scale geophysical variables, such as SST and coastal chlorophyll, are often associated with conditions favoring growth of V. cholerae. However, local environmental factors, meaning biological activity in ponds from where the bulk of populations in endemic regions derive water for daily usage, are either neglected or oversimplified. Using data collected from several sites in two geographically distinct locations in South Asia, we have identified critical local environmental factors associated with cholera outbreak. Of 18 environmental variables monitored for water sources in Mathbaria (a coastal site near the Bay of Bengal) and Bakergonj (an inland site) of Bangladesh, water depth and chlorophyll were found to be important factors associated with initiation of cholera outbreaks. Cholera in coastal regions appears to be related to intrusion. However, monsoonal flooding creates conditions for cholera epidemics in inland regions. This may be one of the first attempts to relate in-situ environmental observations with cholera. We anticipate that it will be useful for further development of prediction models in the resource constrained regions.

  13. On the Evolution of Glaciated Continental Margins

    Science.gov (United States)

    Sverre Laberg, Jan; Rydningen, Tom Arne; Safronova, Polina A.; Forwick, Matthias

    2016-04-01

    Glaciated continental margins, continental margins where a grounded ice sheet repeatedly has been at or near the shelf break, are found at both northern and southern high-latitudes. Their evolution are in several aspects different from their low-latitude counterparts where eustatic sea-level variations possess a fundamental control on their evolution and where fluvial systems provide the main sediment input. From studies of the Norwegian - Barents Sea - Svalbard and NE Greenland continental margins we propose the following factors as the main control on the evolution of glaciated continental margins: 1) Pre-glacial relief controlling the accommodation space, 2) Ice sheet glaciology including the location of fast-flowing ice streams where source area morphology exerts a fundamental control, 3) Composition of the glacigenic sediments where the clay content in previous studies have been found to be important, and 4) Sea-level controlled both by eustacy and isostacy. From three case studies, 1) the western Barents Sea, 2) part of the North Norwegian (Troms), and 3) the Mid-Norwegian margin, the influence on these factors for the sea-floor morphology, sedimentary processes of the continental slope - deep sea and continental margin architecture are discussed. The pre-glacial relief of the mid-Norwegian and Troms margins relates to the onset of rifting and plate break-up from the early Cenozoic while for the SW Barents Sea, plate shear was followed by rifting. A wide zone of extended continental crust occurs offshore mid-Norway while this zone is much narrower offshore Troms leading to a more pronounced pre-glacial relief. Regarding sediment delivery and ice sheet glaciology the western Barents Sea exemplifies very high sediment input corresponding to an estimated average erosion of the source area of ~0.4 mm/yr (SW Barents Sea), much of which is related to subglacial erosion of Mesozoic - Cenozoic sedimentary rocks from large paleo-ice streams. The mid-Norwegian margin

  14. Mantle plumes and continental tectonics.

    Science.gov (United States)

    Hill, R I; Campbell, I H; Davies, G F; Griffiths, R W

    1992-04-10

    Mantle plumes and plate tectonics, the result of two distinct modes of convection within the Earth, operate largely independently. Although plumes are secondary in terms of heat transport, they have probably played an important role in continental geology. A new plume starts with a large spherical head that can cause uplift and flood basalt volcanism, and may be responsible for regional-scale metamorphism or crustal melting and varying amounts of crustal extension. Plume heads are followed by narrow tails that give rise to the familiar hot-spot tracks. The cumulative effect of processes associated with tail volcanism may also significantly affect continental crust.

  15. Assessing the risk of dengue virus transmission in a non-endemic city surrounded by endemic and hyperendemic areas.

    Science.gov (United States)

    Kwan, Tsz Ho; Lee, Shui Shan; Chan, Denise Pui Chung; Cheung, Manton; Kam, Kai Man

    2017-02-01

    To assess the potential risk of dengue transmission in a non-endemic city using a spatial epidemiological approach. Past dengue exposure of the general population was examined by dengue virus (DENV) IgG testing of archived samples from voluntary blood donors. Vector intensities were determined by local ovitrap index (OI). Analyses were made in the context of population statistics at both the district and sub-district level. The overall prevalence of DENV IgG was low at 2.25%. Positive donors were more likely to be older, non-Chinese, and female. Neither the OI nor the location of residence was associated with DENV serology. The sub-district level OI was clustered, but no correlation could be confirmed with the location of residence of positive blood donors. The cumulative exposure of Hong Kong residents to dengue has so far been low. Coupled with the lack of a spatial relationship between exposed cases and vector intensities, a high risk of local transmission of DENV is not supported. The apparently higher exposure likelihood of females could be explained by past infection in workers from dengue endemic countries, while frequent travel could have exposed older adults to DENV. Continued surveillance, risk assessment, and intensive vector control remain essential to prevent the transformation of a non-endemic to an endemic city. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  16. [Study on distribution of endemic arsenism in China].

    Science.gov (United States)

    Jin, Yinlong; Liang, Chaoke; He, Gongli; Cao, Jingxiang

    2003-11-01

    Drinking water and burning coal endemic arsenism as a severe disease is confirmed by National Ministry of Health in China in 1992. It is not uniform survey of the disease for the whole country from its report in 1980 in xijiang. Therefore National Ministry of Scientific and Technology in China supports to study on distribution of endemic arsenism in 21 provinces in China, so that it can know the basic distribution of endemic arsenism in China, and the data results will be a guide for the disease prevention and control. The project used environmental epidemiology study including retrospective epidemiology, present situation survey of the disease in severe areas and sampling investigation in unknown areas, collecting data of exposure population and arsenism cases. At the same time, the data of arsenic level in environment were collected, and environment samples were analyzed by standard chemical method. The both data were statistical analysis by access database and SAS procedure in computer. Through the study, it achieves the expected aim that grasps spreading distribution of drinking water arsenism and burning coal arsenism, including arsenic level in water, coal, food and air, as well as patient's condition of the disease at macroscopic. Drinking water endemic arsenism distributed in 8 provinces, 40 counties, affecting 2,343,238 peoples, among 522566 peoples expositing to the drinking water arsenic higher than 0.05 mg/L, and 7821 arsenism patients were diagnosed. Burning coal endemic arsenism spreads in 2 provinces, 8 counties, affecting 333905 peoples, 48438 peoples exposing to high arsenic of burning coal pollution, and 2402 peoples causing chronic arsenic poising by coal burning. Drinking water endemic arsenism: Nemeng, Shanxi is a severe drinking water endemic region also. Wusu city in Xinjiang is old arsenism area, which reformed drinking water to decrease arsenic, so chronic arsenic poisoning condition decreasing. Reforming drinking water measures to decreees

  17. Rusa alfredi papillomavirus 1 - a novel deltapapillomavirus inducing endemic papillomatosis in the endangered Visayan spotted deer

    National Research Council Canada - National Science Library

    Fux, Robert; Langenmayer, Martin C; Jörgens, Dirk; Schubert, Christina; Heckel, Jens-Ove; Sutter, Gerd

    2016-01-01

    We describe a novel papillomavirus - Rusa alfredi papillomavirus 1 (RalPV1) - which causes endemic fibropapillomatosis in the European conservation breeding population of the highly endangered Visayan spotted deer (Rusa alfredi...

  18. DNA evidence for global dispersal and probable endemicity of protozoa

    Directory of Open Access Journals (Sweden)

    Matthai Lena

    2007-09-01

    Full Text Available Abstract Background It is much debated whether microbes are easily dispersed globally or whether they, like many macro-organisms, have historical biogeographies. The ubiquitous dispersal hypothesis states that microbes are so numerous and so easily dispersed worldwide that all should be globally distributed and found wherever growing conditions suit them. This has been broadly upheld for protists (microbial eukaryotes by most morphological and some molecular analyses. However, morphology and most previously used evolutionary markers evolve too slowly to test this important hypothesis adequately. Results Here we use a fast-evolving marker (ITS1 rDNA to map global diversity and distribution of three different clades of cercomonad Protozoa (Eocercomonas and Paracercomonas: phylum Cercozoa by sequencing multiple environmental gene libraries constructed from 47–80 globally-dispersed samples per group. Even with this enhanced resolution, identical ITS sequences (ITS-types were retrieved from widely separated sites and on all continents for several genotypes, implying relatively rapid global dispersal. Some identical ITS-types were even recovered from both marine and non-marine samples, habitats that generally harbour significantly different protist communities. Conversely, other ITS-types had either patchy or restricted distributions. Conclusion Our results strongly suggest that geographic dispersal in macro-organisms and microbes is not fundamentally different: some taxa show restricted and/or patchy distributions while others are clearly cosmopolitan. These results are concordant with the 'moderate endemicity model' of microbial biogeography. Rare or continentally endemic microbes may be ecologically significant and potentially of conservational concern. We also demonstrate that strains with identical 18S but different ITS1 rDNA sequences can differ significantly in terms of morphological and important physiological characteristics, providing

  19. Origin and intra-island diversification of Sulawesi endemic Adrianichthyidae.

    Science.gov (United States)

    Mokodongan, Daniel F; Yamahira, Kazunori

    2015-12-01

    Although the family Adrianichthyidae is broadly distributed throughout East and Southeast Asia, 19 endemic species, over half of the family, are distributed in Sulawesi, which is an island in Wallacea. However, it remains unclear how this Adrianichthyidae biodiversity hotspot was shaped. In this study, we reconstructed molecular phylogenies for the Sulawesi adrianichthyids and estimated the divergence times of major lineages to infer the detailed history of their origin and subsequent intra-island diversification. The mitochondrial and nuclear phylogenies revealed that Sulawesi adrianichthyids are monophyletic, which indicates that they diverged from a single common ancestor. Species in the earliest branching lineages are currently distributed in the central and southeastern parts of the island, indicating that the common ancestor colonized Sula Spur, which is a large promontory that projects from the Australian continental margin, from Asia by oversea dispersal c.a. 20Mya. The first diversification event on Sulawesi, the split of the genus Adrianichthys, occurred c.a. 16Mya, and resulted in the nesting of Adrianichthys within Oryzias. Strong geographic structure was evident in the phylogeny; many species in the lineages branching off early are riverine and widely distributed in the southeastern and southwestern arms of Sulawesi, which suggests that oversea dispersal between tectonic subdivisions of this island during the late Miocene (7-5Mya) contributed to the distributions and diversification of the early branching lineages. In contrast, most species in the lineages branched off later are endemic to a single tectonic lake or lake system in the central Sulawesi, suggesting that habitat fragmentation due to the Pliocene collisions (c.a. 4Mya) among the tectonic subdivisions was the primary factor for diversification of the late branching, lacustrine lineages. Adrianichthys and some Oryzias in a certain late branching lineage are sympatric in Lake Poso, which

  20. Aligning conservation goals: are patterns of species richness and endemism concordant at regional scales?

    Directory of Open Access Journals (Sweden)

    Ricketts, T. H.

    2001-01-01

    Full Text Available Biodiversity conservation strategies commonly target areas of high species richness and/or high endemism. However, the correlation between richness and endemism at scales relevant to conservation is unclear; these two common goals of conservation plans may therefore be in conflict. Here the spatial concordance between richness and endemism is tested using five taxa in North America: butterflies, birds, mammals, amphibians, and reptiles. This concordance is also tested using overall indices of richness and endemism (incorporating all five taxa. For all taxa except birds, richness and endemism were significantly correlated, with amphibians, reptiles, and the overall indices showing the highest correlations (rs = 0.527-0.676. However, 'priority sets' of ecoregions (i.e., the top 10% of ecoregions based on richness generally overlapped poorly with those based on endemism (< 50% overlap for all but reptiles. These results offer only limited support for the idea that richness and endemism are correlated at broad scales and indicate that land managers will need to balance these dual, and often conflicting, goals of biodiversity conservation.

  1. Patterns of endemism along an elevation gradient in Sierra Nevada (Spain and Lefka Ori (Crete, Greece

    Directory of Open Access Journals (Sweden)

    Fernández-Calzado, R.

    2013-12-01

    Full Text Available Aim: High mountains in the Mediterranean region of Europe are particularly rich in endemic vascular plants. We aimed to compare the altitudinal patterns of vascular plant species richness and the proportion of endemic species in two Mediterranean region: Lefka Ori on the island of Crete (Greece and Sierra Nevada on the Iberian peninsula. Location: Sierra Nevada, Granada (Spain; Lefka Ori, Crete (Greece. Methods: Data from standardised permanent plots settings on summit sites (comprising eight plot sectors, covering the upeermost 10 altitudinal metres of different elevations were used (GLORIA Multi-Summit approach; www.gloria.ac.at. Species numbers, rates of endemic species, and soils temperature were compared by means of ANCOVA and linear regression. Results: The two regions, though climatically similar, showed strikingly different patterns: In Sierra Nevada, the proportion of endemic vascular plants (species restricted to Sierra Nevada showed a stepwise increase from the lowest to the highest summit. In contrast, the proportion of endemic species restricted to Crete was not significantly different between the four summits in Lefka Ori. In both regions the observed trends were largely consistent with the altitudinal distribution of the endemic species obtained from standard floras. Main conclusions: The geographic positions of the two regions, i.e. island versus mainland and the higher elevation of Sierra Nevada are suggested to be the primary causes of the observed differences. The high degree of endemism in the cold environments of Mediterranean mountains’ upper bioclimatic zones indicates a pronounced vulnerability to the impacts of climate change. A continued and intensified species monitoring in the mountains around the Mediterranean basin, therefore, should be considered as a priority research task.Objetivo: Las zonas de alta montaña en la región mediterránea europea son particularmente ricas en plantas vasculares end

  2. From ratites to rats: the size of fleshy fruits shapes species' distributions and continental rainforest assembly.

    Science.gov (United States)

    Rossetto, Maurizio; Kooyman, Robert; Yap, Jia-Yee S; Laffan, Shawn W

    2015-12-01

    Seed dispersal is a key process in plant spatial dynamics. However, consistently applicable generalizations about dispersal across scales are mostly absent because of the constraints on measuring propagule dispersal distances for many species. Here, we focus on fleshy-fruited taxa, specifically taxa with large fleshy fruits and their dispersers across an entire continental rainforest biome. We compare species-level results of whole-chloroplast DNA analyses in sister taxa with large and small fruits, to regional plot-based samples (310 plots), and whole-continent patterns for the distribution of woody species with either large (more than 30 mm) or smaller fleshy fruits (1093 taxa). The pairwise genomic comparison found higher genetic distances between populations and between regions in the large-fruited species (Endiandra globosa), but higher overall diversity within the small-fruited species (Endiandra discolor). Floristic comparisons among plots confirmed lower numbers of large-fruited species in areas where more extreme rainforest contraction occurred, and re-colonization by small-fruited species readily dispersed by the available fauna. Species' distribution patterns showed that larger-fruited species had smaller geographical ranges than smaller-fruited species and locations with stable refugia (and high endemism) aligned with concentrations of large fleshy-fruited taxa, making them a potentially valuable conservation-planning indicator.

  3. Nuclear DNA Contents of Some Endemic Hedysarum L. Species

    OpenAIRE

    1999-01-01

    The nuclear DNA contents and nuclear areas of some endemic Hedysarum L. species were investigated. A significant variation in the DNA content of Hedysarum species was established. The 2C nuclear DNA amount in the Hedysarum species (x = 8) ranged from approximately 4 to 6 picograms. It was found that the variation in the 2C nuclear DNA content was not related to chromosome numbers. However, there was a very high positive linear relationship between nuclear DNA content and nuclear area.

  4. A Long Neglected World Malaria Map: Plasmodium vivax Endemicity in 2010

    Science.gov (United States)

    Gething, Peter W.; Elyazar, Iqbal R. F.; Moyes, Catherine L.; Smith, David L.; Battle, Katherine E.; Guerra, Carlos A.; Patil, Anand P.; Tatem, Andrew J.; Howes, Rosalind E.; Myers, Monica F.; George, Dylan B.; Horby, Peter; Wertheim, Heiman F. L.; Price, Ric N.; Müeller, Ivo; Baird, J. Kevin; Hay, Simon I.

    2012-01-01

    Background Current understanding of the spatial epidemiology and geographical distribution of Plasmodium vivax is far less developed than that for P. falciparum, representing a barrier to rational strategies for control and elimination. Here we present the first systematic effort to map the global endemicity of this hitherto neglected parasite. Methodology and Findings We first updated to the year 2010 our earlier estimate of the geographical limits of P. vivax transmission. Within areas of stable transmission, an assembly of 9,970 geopositioned P. vivax parasite rate (PvPR) surveys collected from 1985 to 2010 were used with a spatiotemporal Bayesian model-based geostatistical approach to estimate endemicity age-standardised to the 1–99 year age range (PvPR1–99) within every 5×5 km resolution grid square. The model incorporated data on Duffy negative phenotype frequency to suppress endemicity predictions, particularly in Africa. Endemicity was predicted within a relatively narrow range throughout the endemic world, with the point estimate rarely exceeding 7% PvPR1–99. The Americas contributed 22% of the global area at risk of P. vivax transmission, but high endemic areas were generally sparsely populated and the region contributed only 6% of the 2.5 billion people at risk (PAR) globally. In Africa, Duffy negativity meant stable transmission was constrained to Madagascar and parts of the Horn, contributing 3.5% of global PAR. Central Asia was home to 82% of global PAR with important high endemic areas coinciding with dense populations particularly in India and Myanmar. South East Asia contained areas of the highest endemicity in Indonesia and Papua New Guinea and contributed 9% of global PAR. Conclusions and Significance This detailed depiction of spatially varying endemicity is intended to contribute to a much-needed paradigm shift towards geographically stratified and evidence-based planning for P. vivax control and elimination. PMID:22970336

  5. The continuing medical mystery of Balkan Endemic Nephropathy

    Science.gov (United States)

    Crosby, Lynn M.; Tatu, Calin A.; Orem, William H.; Pavlovic MD PhD, Nikola

    2015-01-01

    Balkan Endemic Nephropathy (BEN) is a disease of subtle onset and insidious progression that typically occurs between the 4th and 6th decade in long‐resident individuals in highly specific geographic locations of the Balkan region and affects 1 – 5% of the population. Though it does not follow typical Mendelian genetics, there is a familial pattern of occurrence. Although residents may live only a few kilometers apart, certain locations are highly affected while others close by, even as close as across the road, remain unscathed. Because of this geographic selectivity scientists have searched for an environmental cause. It is thought that exposure to the toxic plant Aristolochia clematitis is to blame. Genotoxic N‐heterocyclic or polycyclic aromatic containing coal water leachates entering cultivated soil and drinking water are also a possible cause due to the proximity and predictive power of endemic foci to coal deposits. Evidence for Ochratoxin A fungal poisoning also exists. High levels of phthalates have been measured in BEN‐endemic drinking water. BEN is a probably a multifactorial disease that may result from exposure through some of above‐mentioned environmental sources, with genetic factors contributing. This review will discuss recent research concerning the etiology, potential therapies for the treatment of nephropathy, and unexplored research directions for this chronic kidney disease.

  6. High-Resolution Chirp and Mini-Sparker Seismic-Reflection Data From the Southern California Continental Shelf--Gaviota to Mugu Canyon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This report consists of high-resolution chirp and single-channel Sparker seismic-reflection- profile data from the Santa Barbara Channel, California. These data were...

  7. Raw ODEC Bathy2000 CHIRP subbottom profiler - CHIRP high-resolution Seismic Profile data for the U.S. Arctic Continental Margin.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — ODEC Bathy2000 CHIRP subbottom profiler - CHIRP high-resolution Seismic Profile data were collected in Raw ODEC Bathy2000 CHIRP dat Datagram Format.

  8. High-Resolution Chirp and Mini-Sparker Seismic-Reflection Data From the Southern California Continental Shelf--Gaviota to Mugu Canyon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This report consists of high-resolution chirp and single-channel Sparker seismic-reflection- profile data from the Santa Barbara Channel, California. These data were...

  9. A comparative evaluation of endemic and non-endemic region of visceral leishmaniasis (Kala-azar in India with ground survey and space technology

    Directory of Open Access Journals (Sweden)

    Shreekant Kesari

    2011-08-01

    Full Text Available In visceral leishmaniasis, phlebotomine vectors are targets for control measures. Understanding the ecosystem of the vectors is a prerequisite for creating these control measures. This study endeavours to delineate the suitable locations of Phlebotomus argentipes with relation to environmental characteristics between endemic and non-endemic districts in India. A cross-sectional survey was conducted on 25 villages in each district. Environmental data were obtained through remote sensing images and vector density was measured using a CDC light trap. Simple linear regression analysis was used to measure the association between climatic parameters and vector density. Using factor analysis, the relationship between land cover classes and P. argentipes density among the villages in both districts was investigated. The results of the regression analysis indicated that indoor temperature and relative humidity are the best predictors for P. argentipes distribution. Factor analysis confirmed breeding preferences for P. argentipes by landscape element. Minimum Normalised Difference Vegetation Index, marshy land and orchard/settlement produced high loading in an endemic region, whereas water bodies and dense forest were preferred in non-endemic sites. Soil properties between the two districts were studied and indicated that soil pH and moisture content is higher in endemic sites compared to non-endemic sites. The present study should be utilised to make critical decisions for vector surveillance and controlling Kala-azar disease vectors.

  10. DEPSCoR FY 99: Use of Stochastic Modeling of Stratigraphic Relationships in High Resolution Seismic Reflection Data for Prediction of the Distribution of Acoustic and Geotechnical Property Variability in Near Surface Sediments on the East China Sea Continental Margin

    Science.gov (United States)

    2016-06-13

    Distribution of Acoustic and Geotechnical Property Variability in Near Surface Sediments on the East China Sea Continental Margin Louis R. Bartek Department of...East China Sea Continental Margin 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...collecting data. During survey 221099 in the East China Sea (ECS) and the Yellow Sea (YS) we collected 191 km of 210 cubic inch Generator Injector Air

  11. Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

    NARCIS (Netherlands)

    Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

    2016-01-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes

  12. Prevalence of haemosporidians in a Neotropical endemic bird area

    Directory of Open Access Journals (Sweden)

    Catalina Gonzalez-Quevedo

    2016-06-01

    Full Text Available Haemosporidians are vector-transmitted intracellular parasites that occur in many bird species worldwide and may have important implications for wild bird populations. Surveys of haemosporidians have traditionally focused on Europe and North America, and only recently have they been carried out in the Neotropics, where the prevalence and impacts of the disease have been less studied and are not well understood. In this study we carried out a survey in the endemic bird area of the Sierra Nevada de Santa Marta (SNSM, an isolated coastal massif in northern Colombia that contains a large number of biomes and that is experiencing high rates of habitat loss. We sampled birds from 25 species at 2 different altitudes (1640 and 2100 m asl and determined avian haemosporidian infection by polymerase chain reaction and sequencing a portion of the cytochrome b (cyt b gene of the parasite. From the sampled birds, 32.1% were infected by at least 1 of 12 unique cyt b lineages of haemosporidian genera: Plasmodium, Leucocytozoon, Haemoproteus, and subgenus Parahaemoproteus. We found a higher prevalence of avian haemosporidians at low altitudes (1640 m asl. All endemic bird species we sampled had at least one individual infected with avian haemosporidians. We also found evidence of higher overall prevalence among endemic rather than nonendemic birds, suggesting higher susceptibility in endemic birds. Overall, our findings suggest a high haemosporidian species richness in the bird community of the SNSM. Considering the rate of habitat loss that this area is experiencing, it is important to understand how avian haemosporidians affect bird populations; furthermore, more exhaustive sampling is required to fully comprehend the extent of avian haemosporidian infection in the area.

  13. Initiation of continental accretion: metamorphic conditions

    Science.gov (United States)

    Clement, Conand; Frederic, Mouthereau; Gianreto, Manatschal; Adbeltif, Lahfid

    2017-04-01

    The physical processes involved at the beginning of the continental collision are largely unknown because they are transient and therefore hardly identifiable from the rock record. Despite the importance of key parameters for understanding mountain building processes, especially the formation of deep mountain roots and their impacts on earthquakes nucleation, rock/fluid transfers and oil/gas resources in the continental crust, observations from the earliest collision stages remain fragmentary. Here, we focus on the example of Taiwan, a young and active mountain belt where the transition from oceanic subduction, accretion of the first continental margin to mature collision can be followed in space and time. We present preliminary results and provide key questions regarding the reconstruction of time-pressure-temperature paths of rocks & fluids to allow discriminating between rift-related thermal/rheological inheritance and burial/heating phases during convergence. Previous studies have focused on peak temperatures analyzed by Raman Spectrometry of Carbonaceous Matter from the deeper structural layers exposed in the Central Range of Taiwan. In the pre-rift sediments, these studies reported a positive gradient from West to Est, and values from units. Cross sections and maps with high resolution peak temperatures are in process as well as pressure estimations to determine how the sediments were metamorphosed. In addition to this work, we report a few inherited temperatures in the 390-570 °C range, indicating recycling of organic matter from metasediments that recorded HT events, likely originated from higher grade metamorphic units of mainland China, which have been eroded and deposited in the post-rift sediments.

  14. Bird communities in three forest types in the Pernambuco Centre of Endemism, Alagoas, Brazil

    OpenAIRE

    Lobo-Araújo,Lahert W.; Toledo,Mário T. F.; Márcio A. Efe; Malhado, Ana C. M.; Marcos V. C. Vital; Guilherme S. Toledo-Lima; Phoeve Macario; Jhonatan G. dos Santos; Ladle, Richard J.

    2013-01-01

    The Pernambuco Center of Endemism (PCE) in northeastern Brazil is highly fragmented and degraded. Despite its potential conservation importance the bird fauna in this area is still relatively unknown and there are many remnant fragments that have not been systematically surveyed. Here, we report the results of bird surveys in five forest fragments (one pioneer, two ombrophilous and two seasonal). In total, 162 taxa were recorded, 12 of which are endemic to the PCE. The frequency of endangered...

  15. An Ancient Divide in a Contiguous Rainforest: Endemic Earthworms in the Australian Wet Tropics

    OpenAIRE

    Moreau, Corrie S.; Andrew F Hugall; McDonald, Keith R.; Jamieson, Barrie G. M.; Craig Moritz

    2015-01-01

    Understanding the factors that shape current species diversity is a fundamental aim of ecology and evolutionary biology. The Australian Wet Tropics (AWT) are a system in which much is known about how the rainforests and the rainforest-dependent organisms reacted to late Pleistocene climate changes, but less is known about how events deeper in time shaped speciation and extinction in this highly endemic biota. We estimate the phylogeny of a species-rich endemic genus of earthworms (Terrisswalk...

  16. Rhizospheric Bacterial Community of Endemic Rhododendron arboreum Sm. Ssp. delavayi along Eastern Himalayan Slope in Tawang

    OpenAIRE

    Rajal Debnath; Archana Yadav; Vijai Kumar Gupta; Bhim Pratap Singh; Pratap Jyoti Handique; Ratul Saikia

    2016-01-01

    Information on rhizosphere microbiome of endemic plants from high mountain ecosystems against those of cultivated plantations is inadequate. Comparative bacterial profiles of endemic medicinal plant Rhododendron arboreum Sm. subsp. delavayi rhizosphere pertaining to four altitudinal zonation Pankang Thang (PTSO), Nagula, Y-junction and Bum La (Indo-China border; in triplicates each) along cold adapted Eastern slope of Himalayan Tawang region, India is described here. Significant differences i...

  17. Tracing the temporal and spatial origins of island endemics in the Mediterranean region: a case study from the citrus family (Ruta L., Rutaceae).

    Science.gov (United States)

    Salvo, Gabriele; Ho, Simon Y W; Rosenbaum, Gideon; Ree, Richard; Conti, Elena

    2010-12-01

    Understanding the origin of island endemics is a central task of historical biogeography. Recent methodological advances provide a rigorous framework to determine the relative contribution of different biogeographic processes (e.g., vicariance, land migration, long-distance dispersal) to the origin of island endemics. With its complex but well-known history of microplate movements and climatic oscillations, the Mediterranean region (including the Mediterranean basin and Macaronesia) provides the geographic backdrop for the diversification of Ruta L., the type genus of Rutaceae (citrus family). Phylogenetic, molecular dating, and ancestral range reconstruction analyses were carried out to investigate the extent to which past geological connections and climatic history of the Mediterranean region explain the current distribution of species in Ruta, with emphasis on its island endemics. The analyses showed that Ruta invaded the region from the north well before the onset of the Mediterranean climate and diversified in situ as the climate became Mediterranean. The continental fragment island endemics of the genus originated via processes of land migration/vicariance driven by connections/disconnections between microplates, whereas the oceanic island endemics were the product of a single colonization event from the mainland followed by in situ diversification. This study emphasizes the need for an integrative, hypothesis-based approach to historical biogeography and stresses the importance of temporary land connections and colonization opportunity in the biotic assembly of continental fragment and oceanic islands, respectively.

  18. Continental Rifts and Resources

    Science.gov (United States)

    Stein, Holly J.

    2017-04-01

    Nearly all resource-forming systems involve upward mobility of fluids and melts. In fact, one of the most effective means of chemically transforming the earth's crust can be readily observed in the rift environment. Imposition of rifting is based on deeper stresses that play out in the crust. At its most fundamental level, rifting transfers heat and fluids to the crust. Heat delivered by fluids aids both in transport of metal and maturation of hydrocarbons. The oxidizing capacity of fluids on their arrival in the deep crust, whether derived from old slabs, depleted upper mantle and/or deeper, more primitive mantle, is a fundamental part of the resource-forming equation. Oxidizing fluids transport some metals and breakdown kerogen, the precursor for oil. Reducing fluids transport a different array of metals. The tendency is to study the resource, not the precursor or the non-economic footprint. In doing so, we lose the opportunity to discover the involvement and significance of initiating processes; for example, externally derived fluids may produce widespread alteration in host rocks, a process that commonly precedes resource deposition. It is these processes that are ultimately the transferable knowledge for successful mineral and hydrocarbon exploration. Further limiting our understanding of process is the tendency to study large, highly complex, and economically successful ore-forming or petroleum systems. In order to understand their construction, however, it is necessary to put equal time toward understanding non-economic systems. It is the non-economic systems that often clearly preserve key processes. The large resource-forming systems are almost always characterized by multiple episodes of hydrothermal overprints, making it difficult if not impossible to clearly discern individual events. Understanding what geologic and geochemical features blocked or arrested the pathway to economic success or, even worse, caused loss of a resource, are critical to

  19. Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

    Science.gov (United States)

    Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

    2016-08-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.

  20. Nearshore continental shelf: Morphology, paleomorphology, and sediment transport based on high-resolution geophysical profiling of Monterey Bay National Marine Sanctuary

    Science.gov (United States)

    Anima, Roberto Juan

    The intertwining of the shoreline with its coastal streams, headlands, pocket beaches, coves, and sea cliffs is tied to a nearshore with sea floor outcrops, shore-normal sand-filled low areas, subbottom channels, and variations in sediment texture. The stitching together of the two aspects of this high-energy environment was accomplished by geophysical surveying techniques that uncovered direct connections to each facet of the coastal area between Ano Nuevo and New Brighton Beach. What this work has accomplished is the expansion of our view of a high energy, active margin coastline in a way that reveals aspects of the nearshore that connect onshore coastal features, to previously unknown offshore features in a three dimensional view that incorporates morphology, processes, and time. This work gives a look at a nearshore that hints of a low sea level stand coastal scene not unlike our present. It uncovers relic stream channels that are direct ancestors of the present coastal streams. And finally, it proposes a conceptual model of how modern processes are constantly at work to shape and reshape this dynamic environment in order to fulfill its goal of moving sediment alongshore.

  1. SHRIMP single zircon U-Pb dating of the Kongling high-grade metamorphic terrain: Evidence for >3.2 Ga old continental crust in the Yangtze craton

    Institute of Scientific and Technical Information of China (English)

    GAO; Shan; (

    2001-01-01

    [1]Liu, G. L., New progress in the geochronology of the Kongling terrain, Regional Geology of China, 1987, 1: 95.[2]Zheng, W. Z., Liu, G. L., Wang, X. W., Geochronology of the Archean Kongling terrain, Bull. Yichang Inst. Geol. Miner. Resour. (in Chinese), 1991, 16: 97-105.[3]Yuan, H. H., Zhang, Z. L., Liu, W. et al., Dating of zircons by evaporation method and its application, Mineral. Petrol. (in Chinese), 1991, 11: 72.-79[4]Ling, W. L., Gao, S., Zheng, H. F. et al., Sm-Nd isotopic dating of Kongling terrain, Chinese. Sci. Bull., 1998, 43(1): 86-89.[5]Gao, S., Ling, W. L., Qiu, Y. et al., Contrasting geochemical and Sm-Nd isotopic compositions of Archean metasediments from the Kongling high-grade terrain of the Yangtze craton: evidence for cratonic evolution and redistribution of REE during crustal anatexis, Geochim. Cosmochim. Acta, 1999, 63: 2071-2088.[6]Gao, S., Zhang, B. R., The discovery of Archean TTG gneisses in northern Yangtze craton and their implications, Earth Sci. (in Chinese, with English abstract), 1990, 15: 675-679.[7]Dong, S. B., Metamorphism and Its Relation to the Crustal Evolution in China (in Chinese), Beijing: Geological Publishing House, 1986. [8]Composton, W., Williams, I. S., Meyer, C., U-Pb geochronology of zircons from lunar breccia 73217 using sensitive high mass-resolution ion microprobe, J. Geophys. Res., 1984, 89(B): 252-534.[9]Williams, I. S., Composton, W., Black, L. P et al., Unsupported radiogenic Pb in zircon: a case of anomalously high Pb-Pb, U-Pb and Th-Pb ages, Contrib. Mineral. Petrol., 1984, 88: 322-327.[10] Nelson, D. R., Evolution of the Archean granite-greenstone terrains of the Eastern Goldfileds, Western Australia: SHRIMP U-Pb zircon constraints, Precambrian Res., 1997, 83: 57-81.[11] Ling, W. L., Geochronology and crustal growth of the Paleoproterozoic basements along the northern margin of the Yangzte craton, Earth Sci., 1996, 21(5): 491—493.

  2. Human African trypanosomiasis in endemic populations and travellers.

    Science.gov (United States)

    Blum, J A; Neumayr, A L; Hatz, C F

    2012-06-01

    Human African trypanosomiasis (HAT) or sleeping sickness is caused by the protozoan parasites Trypanosoma brucei (T.b.) gambiense (West African form) and T.b. rhodesiense (East African form) that are transmitted by the bite of the tsetse fly, Glossina spp.. Whereas most patients in endemic populations are infected with T.b. gambiense, most tourists are infected with T.b. rhodesiense. In endemic populations, T.b. gambiense HAT is characterized by chronic and intermittent fever, headache, pruritus, and lymphadenopathy in the first stage and by sleep disturbances and neuro-psychiatric disorders in the second stage. Recent descriptions of the clinical presentation of T.b. rhodesiense in endemic populations show a high variability in different foci. The symptomatology of travellers is markedly different from the usual textbook descriptions of African HAT patients. The onset of both infections is almost invariably an acute and febrile disease. Diagnosis and treatment are difficult and rely mostly on old methods and drugs. However, new molecular diagnostic technologies are under development. A promising new drug combination is currently evaluated in a phase 3 b study and further new drugs are under evaluation.

  3. Evolution of endemism on a young tropical mountain.

    Science.gov (United States)

    Merckx, Vincent S F T; Hendriks, Kasper P; Beentjes, Kevin K; Mennes, Constantijn B; Becking, Leontine E; Peijnenburg, Katja T C A; Afendy, Aqilah; Arumugam, Nivaarani; de Boer, Hugo; Biun, Alim; Buang, Matsain M; Chen, Ping-Ping; Chung, Arthur Y C; Dow, Rory; Feijen, Frida A A; Feijen, Hans; Feijen-van Soest, Cobi; Geml, József; Geurts, René; Gravendeel, Barbara; Hovenkamp, Peter; Imbun, Paul; Ipor, Isa; Janssens, Steven B; Jocqué, Merlijn; Kappes, Heike; Khoo, Eyen; Koomen, Peter; Lens, Frederic; Majapun, Richard J; Morgado, Luis N; Neupane, Suman; Nieser, Nico; Pereira, Joan T; Rahman, Homathevi; Sabran, Suzana; Sawang, Anati; Schwallier, Rachel M; Shim, Phyau-Soon; Smit, Harry; Sol, Nicolien; Spait, Maipul; Stech, Michael; Stokvis, Frank; Sugau, John B; Suleiman, Monica; Sumail, Sukaibin; Thomas, Daniel C; van Tol, Jan; Tuh, Fred Y Y; Yahya, Bakhtiar E; Nais, Jamili; Repin, Rimi; Lakim, Maklarin; Schilthuizen, Menno

    2015-08-20

    Tropical mountains are hot spots of biodiversity and endemism, but the evolutionary origins of their unique biotas are poorly understood. In varying degrees, local and regional extinction, long-distance colonization, and local recruitment may all contribute to the exceptional character of these communities. Also, it is debated whether mountain endemics mostly originate from local lowland taxa, or from lineages that reach the mountain by long-range dispersal from cool localities elsewhere. Here we investigate the evolutionary routes to endemism by sampling an entire tropical mountain biota on the 4,095-metre-high Mount Kinabalu in Sabah, East Malaysia. We discover that most of its unique biodiversity is younger than the mountain itself (6 million years), and comprises a mix of immigrant pre-adapted lineages and descendants from local lowland ancestors, although substantial shifts from lower to higher vegetation zones in this latter group were rare. These insights could improve forecasts of the likelihood of extinction and 'evolutionary rescue' in montane biodiversity hot spots under climate change scenarios.

  4. Patterns of Freshwater Species Richness, Endemism, and Vulnerability in California.

    Directory of Open Access Journals (Sweden)

    Jeanette K Howard

    Full Text Available The ranges and abundances of species that depend on freshwater habitats are declining worldwide. Efforts to counteract those trends are often hampered by a lack of information about species distribution and conservation status and are often strongly biased toward a few well-studied groups. We identified the 3,906 vascular plants, macroinvertebrates, and vertebrates native to California, USA, that depend on fresh water for at least one stage of their life history. We evaluated the conservation status for these taxa using existing government and non-governmental organization assessments (e.g., endangered species act, NatureServe, created a spatial database of locality observations or distribution information from ~400 data sources, and mapped patterns of richness, endemism, and vulnerability. Although nearly half of all taxa with conservation status (n = 1,939 are vulnerable to extinction, only 114 (6% of those vulnerable taxa have a legal mandate for protection in the form of formal inclusion on a state or federal endangered species list. Endemic taxa are at greater risk than non-endemics, with 90% of the 927 endemic taxa vulnerable to extinction. Records with spatial data were available for a total of 2,276 species (61%. The patterns of species richness differ depending on the taxonomic group analyzed, but are similar across taxonomic level. No particular taxonomic group represents an umbrella for all species, but hotspots of high richness for listed species cover 40% of the hotspots for all other species and 58% of the hotspots for vulnerable freshwater species. By mapping freshwater species hotspots we show locations that represent the top priority for conservation action in the state. This study identifies opportunities to fill gaps in the evaluation of conservation status for freshwater taxa in California, to address the lack of occurrence information for nearly 40% of freshwater taxa and nearly 40% of watersheds in the state, and to

  5. Dengue Virus Seroconversion in Travelers to Dengue-Endemic Areas.

    Science.gov (United States)

    Olivero, Rosemary M; Hamer, Davidson H; MacLeod, William B; Benoit, Christine M; Sanchez-Vegas, Carolina; Jentes, Emily S; Chen, Lin H; Wilson, Mary E; Marano, Nina; Yanni, Emad A; Ooi, Winnie W; Karchmer, Adolf W; Kogelman, Laura; Barnett, Elizabeth D

    2016-11-02

    We conducted a prospective study to measure dengue virus (DENV) antibody seroconversion in travelers to dengue-endemic areas. Travelers seen in the Boston Area Travel Medicine Network planning to visit dengue-endemic countries for ≥ 2 weeks were enrolled from 2009 to 2010. Pre- and post-travel blood samples and questionnaires were collected. Post-travel sera were tested for anti-DENV IgG by indirect IgG enzyme-linked immunosorbent assay (ELISA) and anti-DENV IgM by capture IgM ELISA. Participants with positive post-travel anti-DENV IgG or IgM were tested for pre-travel anti-DENV IgG and IgM; they were excluded from the seroconversion calculation if either pre-travel anti-DENV IgG or IgM were positive. Paired sera and questionnaires were collected for 62% (589/955) of enrolled travelers. Most participants were 19-64 years of age, female, and white. The most common purposes of travel were tourism and visiting friends and relatives; most trips were to Asia or Africa. Median length of travel was 21 days. DENV antibody seroconversion by either anti-DENV IgM or IgG ELISA was 2.9-6.8%; lower range percent excluded potential false-positive anti-DENV IgG due to receipt of yellow fever or Japanese encephalitis vaccines at enrollment; upper range percent excluded proven false-positive anti-DENV IgM. Eighteen percent of those with seroconversion reported dengue-like symptoms. Seroconversion was documented for travel to Africa as well as countries and regions known to be highly dengue endemic (India, Brazil, southeast Asia). Given widespread risk of dengue, travel medicine counseling should include information on risk of dengue in endemic areas and advice on preventing insect bites and seeking prompt medical attention for febrile illness.

  6. Selenium deficiency as a possible factor in the pathogenesis of myxoedematous endemic cretinism.

    Science.gov (United States)

    Goyens, P; Golstein, J; Nsombola, B; Vis, H; Dumont, J E

    1987-04-01

    Myxoedematous endemic cretinism is prevalent in African goitre endemies. It has been related to a thyroid 'exhaustion' atrophy occurring near birth. It is proposed that this might result from the low resistance of a fragile tissue to enhanced H2O2 generation under intense thyroid stimulation by thyrotropin. In support of this hypothesis, low selenium and glutathione peroxidase serum levels have been found in the African endemic area of the Idjwi Island (Kivu, Zaire). Serum selenium and plasma glutathione peroxidase were lower in the area of high endemicity of goitre and cretinism (Northern part of the Island). However, only the former difference is statistically significant. These data thus suggest a role of oligoelements and oxygen toxicity in the pathogenesis of endemic cretinism.

  7. Relationship between weathered coal deposits and the etiology of Balkan endemic nephropathy

    Science.gov (United States)

    Feder, G.L.; Radovanovic, Z.; Finkelman, R.B.

    1991-01-01

    Field studies in epidemiology and environmental geochemistry in areas in Yugoslavia containing villages with a high incidence of Balkan endemic nephropathy (BEN), indicate a possible relationship between the presence of low-rank coal deposits and the etiology of BEN. Preliminary results from qualitative chemical analyses of drinking water from shallow farm wells indicate the presence of soluble polar aromatic and polynuclear aromatic hydrocarbons. These compounds may be derived from weathering of low-rank coals occurring in the vicinity of the endemic villages. All of the endemic villages are in alluvial valleys of tributaries to the Danube River. All except one of the clusters of endemic villages are located in the vicinity of known Pliocene age coals. Detailed sampling of the drinking waters and the nearby coals are being undertaken to identify a possible etiologic factor.

  8. Prevention of endemic goitre with iodized salt*

    Science.gov (United States)

    Sooch, S. S.; Deo, M. G.; Karmarkar, M. G.; Kochupillai, N.; Ramachandran, K.; Ramalingaswami, V.

    1973-01-01

    The paper describes a study, carried out over 16 years, of the use of iodized salt for the control of endemic goitre in a valley of the Himalayan foothills. From 1956, salt was fortified with either potassium iodide or potassium iodate to provide an estimated daily intake of 200 μg per head. There was a progressive and significant decline in goitre prevalence, together with a return of the pattern of iodine metabolism to within normal limits. It is concluded that endemic goitre can be successfully controlled by iodization of domestic salt. PMID:4546523

  9. Prevention of endemic goitre with iodized salt.

    Science.gov (United States)

    Sooch, S S; Deo, M G; Karmarkar, M G; Kochupillai, N; Ramachandran, K; Ramalingaswami, V

    1973-01-01

    The paper describes a study, carried out over 16 years, of the use of iodized salt for the control of endemic goitre in a valley of the Himalayan foothills. From 1956, salt was fortified with either potassium iodide or potassium iodate to provide an estimated daily intake of 200 mug per head. There was a progressive and significant decline in goitre prevalence, together with a return of the pattern of iodine metabolism to within normal limits. It is concluded that endemic goitre can be successfully controlled by iodization of domestic salt.

  10. Deformation of a continental margin sequence under a thrust sheet: complex stress history in a high pressure cell revealed by vein systems in the Oman Mountains

    Science.gov (United States)

    Virgo, Simon; Urai, Janos L.; Grobe, Arne

    2016-04-01

    Seven deformation phases can be mapped in mesozoic carbonates of the Jebel Akhdar mountains in North Oman. These include an early horizontal NE-SW directed extension that produced bedding confined vein sets with evidence for anticlockwise rotation of the stress field over time, interpreted to have developed during the thrust sheet emplacement. It is followed by a phase of top-NE bedding parallel shearing which rotates these veins on the North side of the mountains. The next phase is normal to oblique slip faults followed by at least two phases of strike-slip deformation. A "background" ductile deformation (maximum burial temperatures of 250 °C) is shown bu deformed fossils and diagenetic concretions. Each of these phases is consistently documented by a large number of observations of overprinting in nearly continuous outcrops. Each deformation phase produces vein sets that do not only differ in orientation but also in occurrence and appearance. Early vein sets exhibit a high stratigraphic variability, but are laterally very stable. With the onset of faulting, the stratigraphic variability decreases and the lateral variability becomes more significant. Even though the area offers excellent outcrop conditions with nearly 100% exposure, it is virtually impossible to find two outcrops that exhibit the same vein patterns. This has interesting implications for vein system analysis and is due to two reasons: (1) the stratigraphic and lateral variability of occurrence and orientation of each vein set cause different combination of vein sets do develop in different layers (2) Intersecting vein sets can show very different interaction such as crosscutting and reactivation, depending on the mechanical properties of the host rock and the veins.

  11. Asymmetry of high-velocity lower crust on the South Atlantic rifted margins and implications for the interplay of magmatism and tectonics in continental break-up

    Directory of Open Access Journals (Sweden)

    K. Becker

    2014-06-01

    Full Text Available High-velocity lower crust (HVLC and seaward dipping reflector sequences (SDRs are typical features of volcanic rifted margins. However, the nature and origin of HVLC is under discussion. Here we provide a comprehensive analysis of deep crustal structures in the southern segment of the South Atlantic and an assessment of HVLC along the margins. Two new seismic refraction lines off South America fill a gap in the data coverage and together with five existing velocity models allow a detailed investigation of the lower crustal properties on both margins. An important finding is the major asymmetry in volumes of HVLC on the conjugate margins. The seismic refraction lines across the South African margin reveal four times larger cross sectional areas of HVLC than at the South American margin, a finding that is in sharp contrast to the distribution of the flood basalts in the Paraná-Etendeka Large Igneous Provinces (LIP. Also, the position of the HVLC with respect to the seaward dipping reflector sequences varies consistently along both margins. Close to the Falkland-Agulhas Fracture Zone a small body of HVLC is not accompanied by seaward dipping reflectors. In the central portion of both margins, the HVLC is below the inner seaward dipping reflector wedges while in the northern area, closer to the Rio Grande Rise/Walvis Ridge, large volumes of HVLC extend far seawards of the inner seaward dipping reflectors. This challenges the concept of a simple extrusive/intrusive relationship between seaward dipping reflector sequences and HVLC, and it provides evidence for formation of the HVLC at different times during the rifting and break-up process. We suggest that the drastically different HVLC volumes are caused by asymmetric rifting in a simple shear dominated extension.

  12. Organic acids in continental background aerosols

    Science.gov (United States)

    Limbeck, Andreas; Puxbaum, Hans

    With a newly developed method aerosol samples from three distinctly different continental sites were analyzed: an urban site (Vienna), a savanna site in South Africa (Nylsvley Nature Reserve, NNR) and a free tropospheric continental background site (Sonnblick Observatory, SBO). In all samples a range of monocarboxylic acids (MCAs) and dicarboxylic acids (DCAs) has been identified and quantified. The three most abundant MCAs in Vienna were the C18, C16 and C14 acids with concentrations of 66, 45 and 36 ng m -3, respectively. At the mid tropospheric background site (SBO) the three most abundant MCAs were the C18, C16 and C12 acid. For the DCAs at all three sites oxalic, malonic and succinic acid were the dominant compounds. For some individual compounds an information about the sources could be obtained. For example the determined unsaturated MCAs in South Africa appear to result from biogenic sources whereas in Vienna those acids are considered to be derived from combustion processes. Oxalic and glyoxalic acid appear to have a free tropospheric air chemical source. The relative high amounts at SBO in comparison to Vienna can only be explained by secondary formation of oxalic acid in the atmosphere.

  13. Impact of moisture source regions on the isotopic composition of precipitation events at high-mountain continental site Kasprowy Wierch, southern Poland

    Science.gov (United States)

    Rozanski, Kazimierz; Chmura, Lukasz; Dulinski, Marek

    2016-04-01

    Five-year record of deuterium and oxygen-18 isotope composition of precipitation events collected on top of the Kasprowy Wierch mountain (49° 14'N, 19° 59'E, 1989 m a.s.l.) located in north-western High Tatra mountain ridge, southern Poland, is presented and discussed. In total 670 precipitation samples have been collected and analysed. Stable isotope composition of the analysed precipitation events varied in a wide range, from -2.9 to -26.6‰ for δ18O and from -7 to -195 ‰ for δ2H. The local meteoric water line (LMWL) defined by single events data (δ2H=(7.86±0.05)δ18O+(12.9±0.6) deviate significantly from the analogous line defined by monthly composite precipitation data available for IAEA/GNIP station Krakow-Balice (50o04'N, 19o55'E, 220 m a.s.l.), located ca. 100 km north of Kasprowy Wierch ((δ2H=(7.82±0.11)δ18O+(6.9±1.1). While slopes of those two LMWLs are statistically indistinguishable, the intercept of Kasprowy Wierch line is almost two times higher that that characterizing Krakow monthly precipitation. This is well-documented effect associated with much higher elevation of Kasprowy Wierch sampling site when compared to Krakow. The isotope data for Kasprowy Wierch correlate significantly with air temperature, with the slope of the regression line being equal 0.35±0.02 ‰oC for δ18O, whereas no significant correlation with precipitation amount could be established. The impact of moisture source regions on the isotopic composition of precipitation events collected at Kasprowy Wierch site was analysed using HYSPLITE back trajectory model. Five-days back trajectories were calculated for all analysed precipitation events and seasonal maps of trajectory distribution were produced. They illustrate changes in the prevailing transport patterns of air masses bringing precipitation to the sampling site. Back trajectories for the events yielding extreme isotopic composition of precipitation collected at Kasprowy Wierch were analyzed in detail

  14. Endemic insular and coastal Tunisian date palm genetic diversity.

    Science.gov (United States)

    Zehdi-Azouzi, Salwa; Cherif, Emira; Guenni, Karim; Abdelkrim, Ahmed Ben; Bermil, Aymen; Rhouma, Soumaya; Salah, Mohamed Ben; Santoni, Sylvain; Pintaud, Jean Christophe; Aberlenc-Bertossi, Frédérique; Hannachi, Amel Salhi

    2016-04-01

    The breeding of crop species relies on the valorisation of ancestral or wild varieties to enrich the cultivated germplasm. The Tunisian date palm genetic patrimony is being threatened by diversity loss and global climate change. We have conducted a genetic study to evaluate the potential of spontaneous coastal resources to improve the currently exploited Tunisian date palm genetic pool. Eighteen microsatellite loci of Phoenix dactylifera L. were used to compare the genetic diversity of coastal accessions from Kerkennah, Djerba, Gabès and continental date palm accessions from Tozeur. A collection of 105 date palms from the four regions was analysed. This study has provided us with an extensive understanding of the local genetic diversity and its distribution. The coastal date palm genotypes exhibit a high and specific genetic diversity. These genotypes are certainly an untapped reservoir of agronomically important genes to improve cultivated germplasm in continental date palm.

  15. Bird pollination of Canary Island endemic plants

    Science.gov (United States)

    Ollerton, Jeff; Cranmer, Louise; Stelzer, Ralph J.; Sullivan, Steve; Chittka, Lars

    2009-02-01

    The Canary Islands are home to a guild of endemic, threatened bird-pollinated plants. Previous work has suggested that these plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently, they appear to have co-opted generalist passerine birds as sub-optimal pollinators. To test this idea, we carried out a quantitative study of the pollination biology of three of the bird-pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and bee pollinators. We measured pollinator visitation rates, nectar standing crops as well as seed-set and pollen removal and deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10 days) of Canarina and Isoplexis suggests that they have evolved a bird pollination system that effectively exploits these low frequency non-specialist pollen vectors and is in no way sub-optimal. Seed set in two of the three species was high and was significantly reduced or zero in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self-incompatible horticultural clones of a single genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff ( Phylloscopus canariensis) was an effective pollinator of these species.

  16. Potential for Suboxic Ammonium Oxidation in Louisiana Continental Shelf Sediments

    Science.gov (United States)

    Sediments deposited onto the Louisiana continental shelf (LCS) west of the Mississippi River Delta form mobile muds varying in thickness from meters near the outfall to centimeters on the western portion of the shelf. The muds have high concentrations of iron which promote rapid...

  17. Microbial Communities in Sediments across the Louisiana Continental Shelf

    Science.gov (United States)

    The Louisiana continental Shelf (LCS) is a dynamic system that receives discharges from two large rivers. It has a stratified water column that is mixed by winter storms, hypoxic bottom water from spring to fall, and a muddy seafloor with highly mixed surficial sediments. Spatia...

  18. Endemic plants harbour specific Trichoderma communities with an exceptional potential for biocontrol of phytopathogens.

    Science.gov (United States)

    Zachow, Christin; Berg, Christian; Müller, Henry; Monk, Jana; Berg, Gabriele

    2016-10-10

    Trichoderma strains exhibit enormous potential for applications in biotechnology, in particular as biocontrol agents against pathogens. However, little is known about the diversity of plant-associated Trichoderma communities at a global scale and their antagonistic spectrum. In order to gather information about structure and function, we compared Trichoderma biomes of endemic (Aeonium, Diospyros, Hebe, Rhododendron) and cosmopolitan plants (Zea mays) in a global study encompassing the area Northwest Africa to New Zealand via the European Alps and Madagascar. At the quantitative level we found no differences between cosmopolitan and endemic plants. Statistically significant differences were detected at the qualitative level: Trichoderma populations of endemic plants were highly specific and diverse with hot spots appearing in Madagascar and New Zealand. By contrast, maize plants from all sites shared the majority of Trichoderma species (65.5%). Interestingly, the high above ground biodiversity in ecosystems containing endemic plants was confirmed by a high below ground Trichoderma diversity. Despite the differences, we found a global Trichoderma core community shared by all analysed plants, which was dominated by T. koningii and T. koningiopsis. Amplicon-based network analyses revealed a high similarity between maize Trichoderma grown world-wide and distinct populations of endemic plants. Furthermore, Trichoderma strains from endemic plants showed a higher antagonistic activity against fungal pathogens compared to maize-associated strains. Our results showed that endemic plants are associated with a specific Trichoderma microbiome which possesses a high antagonistic activity indicating that it has potential to be used for biocontrol purposes. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Thermal models pertaining to continental growth

    Science.gov (United States)

    Morgan, Paul; Ashwal, Lew

    1988-01-01

    Thermal models are important to understanding continental growth as the genesis, stabilization, and possible recycling of continental crust are closely related to the tectonic processes of the earth which are driven primarily by heat. The thermal energy budget of the earth was slowly decreasing since core formation, and thus the energy driving the terrestrial tectonic engine was decreasing. This fundamental observation was used to develop a logic tree defining the options for continental growth throughout earth history.

  20. Analog Modeling of Continental Lithosphere Subduction

    Science.gov (United States)

    Willingshofer, E.; Sokoutis, D.; Luth, S.; Beekman, F.; Cloetingh, S.

    2012-12-01

    Lithospheric-scale analog modeling sheds light on the consequences of decoupling within the continental lithosphere and along plate interfaces during continental collision. The model results provide valuable information in terms of strain localization, deformation of the subducting slab and the evolution and architecture of the overlying mountain belt and its topography. A weak layer has been implemented in three-layer models to simulate decoupling along the plate interface and at different levels of the lithosphere (brittle-ductile transition, entire lower crust, crust-mantle boundary). Additionally, varying the strength of the mantle lithosphere of both the upper as well as the lower plate regulated the degree of plate coupling. Plate boundaries were orthogonal to the convergence direction. All models emphasize that strong decoupling at the plate interface is a pre-requisite for the subduction of continental lithosphere. In addition, deformation of the subducting slab was found to be sensitive to the strength contrast between the subduction zone and the mantle lithosphere of the downgoing as well as the upper plate. As such, a low strength contrast between the plate interface and the lower plate leads to deformation of the subducting slab by thickening and the development of a shallow slab. Conversely, when the strength contrast is high, deep slabs evolve which undergo relatively less deformation. Furthermore, the level of decoupling in the downgoing plate governs how much continental crust is subducted together with the mantle lithosphere. Shallow decoupling, at the brittle-ductile transition, results in subduction of the lower crust whereas small amounts of lower crust are subducted when decoupling occurs at the level of the Moho. Weak plate coupling and a weak lower crust of the lower plate steer the evolution of mountain belts such that deformation propagates outward, in the direction of the incoming plate, by successive imbrication of upper crustal thrust

  1. Antibody reactivities to glutamate-rich peptides of Plasmodium falciparum parasites in humans from areas of different malaria endemicity

    DEFF Research Database (Denmark)

    Jakobsen, P H; Theander, T G; Hviid, L;

    1996-01-01

    in individuals from malaria-endemic areas of Sudan, Indonesia and The Gambia to study antibody responses to these peptides in donors living in areas of different malaria endemicity. IgG and IgM reactivities to the peptides increased with malaria endemicity, although there were no differences in reactivities...... to the GLURP peptide between non-exposed donors and donors living in areas of low malaria endemicity. IgG reactivities to the GLURP peptide in Sudanese adults were high one month after treatment in all adults tested, while IgG reactivities to the ABRA peptide were infrequent. IgM responses to the peptides...... in areas of low malaria endemicity....

  2. Distribution of Mycobacterium ulcerans in buruli ulcer endemic and non-endemic aquatic sites in Ghana.

    Directory of Open Access Journals (Sweden)

    Heather R Williamson

    Full Text Available Mycobacterium ulcerans, the causative agent of Buruli ulcer, is an emerging environmental bacterium in Australia and West Africa. The primary risk factor associated with Buruli ulcer is proximity to slow moving water. Environmental constraints for disease are shown by the absence of infection in arid regions of infected countries. A particularly mysterious aspect of Buruli ulcer is the fact that endemic and non-endemic villages may be only a few kilometers apart within the same watershed. Recent studies suggest that aquatic invertebrate species may serve as reservoirs for M. ulcerans, although transmission pathways remain unknown. Systematic studies of the distribution of M. ulcerans in the environment using standard ecological methods have not been reported. Here we present results from the first study based on random sampling of endemic and non-endemic sites. In this study PCR-based methods, along with biofilm collections, have been used to map the presence of M. ulcerans within 26 aquatic sites in Ghana. Results suggest that M. ulcerans is present in both endemic and non-endemic sites and that variable number tandem repeat (VNTR profiling can be used to follow chains of transmission from the environment to humans. Our results suggesting that the distribution of M. ulcerans is far broader than the distribution of human disease is characteristic of environmental pathogens. These findings imply that focal demography, along with patterns of human water contact, may play a major role in transmission of Buruli ulcer.

  3. Geographic patterns of endemic seed plant genera diversity in China

    OpenAIRE

    Shengbin Chen; Zhiyun Ouyang; Yu Fang; Zhenji Li

    2011-01-01

    Endemism describes the phenomenon that the distribution of individual species/taxa is critically restricted to a specific region. Seed plant genera endemic to China (endemic genera) are those with their main geographic distribution range within the borders of China. The geographic patterns of endemic genera can not only guide conservation planning, but these organisms are also important biological resources. We gath-ered data of 173 localities on environmental and spatial factors, and regiona...

  4. Moho and magmatic underplating in continental lithosphere

    DEFF Research Database (Denmark)

    Thybo, Hans; Artemieva, Irina M.

    2013-01-01

    fractionation during cooling and solidification in the lower crust. Separation of the low density material from the high-density residue may be a main process of formation of continental crust with its characteristic low average density, also during the early evolution of the Earth. Despite the assumed...... importance of underplating processes and associated fractionation, the available geophysical images of underplated material remain relatively sparse and confined to specific tectonic environments. Direct ponding of magma at the Moho is only observed in very few locations, probably because magma usually...... interacts with the surrounding crustal rocks which leads to smearing of geophysical signals from the underplated material. In terms of processes, there is no direct discriminator between the traditional concept of underplated material and lower crustal magmatic intrusions in the form of batholiths and sill...

  5. Oceanography of the Southeastern Continental Shelf

    Science.gov (United States)

    This volume, the second in the Coastal and Estuarine Sciences series, provides a synthesis of the physical, chemical, and biological oceanography of the South Atlantic Bight (SAB). The results presented derive from a decade-long multidisciplinary investigation of the SAB continental shelf regime.The SAB extends from West Palm Beach, Fla., where the narrow south Florida shelf begins to broaden, to Cape Hatteras, N.C., where the shelf again narrows. This broad and shallow area is distinguished by the proximity of the Gulf Stream to the shelf break. Large contrasts in the distribution of properties, the strength of oceanic and atmospheric forces, and the high frequency (4-12 days) at which these forces vary have created a unique natural laboratory in which a variety of oceanic processes may be studied.

  6. Comparative riftology: insights from crustal structure into the evolution of continental rifts and passive continental margins

    Science.gov (United States)

    Kley, Jonas; Stein, Carol; Stein, Seth; Keller, Randy; Wysession, Michael; Frederiksen, Andrew

    2017-04-01

    Continental rifts evolve to seafloor spreading and are preserved in passive margins, or fail and remain as fossil features in continents. Rifts at different stages give insight into these different evolutionary paths. Of particular interest is how volcanic passive margins evolve. These features are characterized by sequences of volcanic rocks yielding magnetic anomalies landward of and sometimes larger than the oldest spreading anomalies. Seaward-dipping reflectors (SDR) occur in stretched continental crust landward of the oldest oceanic crust and are underplated by high-velocity lower crustal bodies. How and when these features form remains unclear. Insights are given by the Midcontinent Rift (MCR), formed by 1.1 Ga rifting of Amazonia from Laurentia, that failed once seafloor spreading was established elsewhere. MCR volcanics are much thicker than other continental flood basalts, due to deposition in a narrow rift rather than a broad region, giving a rift's geometry but a LIP's magma volume. The MCR provides a snapshot of the deposition of a thick highly magnetized volcanic section during rifting. Surface exposures and seismic-reflection data in and near Lake Superior show a rift basin filled by inward-dipping flood basalt layers. Had the rift evolved to seafloor spreading, the basin would have split into two sets of volcanics with opposite-facing SDRs, each with a strong magnetic anomaly. Because the rift formed as a series of alternating half-grabens, structural asymmetries between conjugate margins can naturally occur. Hence the MCR shows that many features form prior to breakup. Because the MCR was massively inverted by regional compression long after it failed and was uplifted, its structure is better known than failed rifts that incurred lesser degrees of inversion. It provides an end member for the evolution of actively extending rifts, characterized by upwelling mantle and negative gravity anomalies, in contrast to failed and inverted rifts without

  7. 26 CFR 1.638-1 - Continental Shelf areas.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Continental Shelf areas. 1.638-1 Section 1.638-1...) INCOME TAXES (CONTINUED) Continental Shelf Areas § 1.638-1 Continental Shelf areas. (a) General rule. For.... The terms Continental Shelf of the United States and Continental Shelf of a possession of the United...

  8. Features and distribution patterns of Chinese endemic seed plant species

    Institute of Scientific and Technical Information of China (English)

    Ji-Hong HUANG; Jian-Hua CHEN; Jun-Sheng YING; Ke-Ping MA

    2011-01-01

    We compiled and identified a list of Chinese. endemic seed plant species based on a large number of published References and expert reviews. The characters of these seed plant species and their distribution patterns were described at length. China is rich in endemic seed plants, with a total of 14 939 species (accounting for 52.1%of its total seed plant species) belonging to 1584 genera and 191 families. Temperate families and genera have a significantly higher proportion of endemism than cosmopolitan and tropical ones. The most primitive and derived groups have significantly higher endemism than the other groups. The endemism of tree, shrub, and liana or vine is higher than that of total species; in contrast, the endemism of herb is lower than that of total species. Geographically,these Chinese endemic plants are mainly distributed in Yunnan and Sichuan provinces, southwest China. Species richness and proportion of these endemic plants decrease with increased latitude and have a unimodal response to altitude. The peak value of proportion of endemism is at higher altitudes than that of total species and endemic species richness. The proportions of endemic shrub, liana or vine, and herb increase with altitude and have a clear unimodal curve. In contrast, the proportion of tree increases with altitude, with a sudden increase at~4000 m and has a completely different model. To date, our study provides the most comprehensive list of Chinese endemic seed plant species and their basic composition and distribution features.

  9. [Endemic zoonosis in Mediterranean area].

    Science.gov (United States)

    Fenga, Concettina; Pugliese, Michela

    2013-01-01

    The Mediterranean is historically considered an area of high concentration of zoonoses. Mediterranean countries socio-economic features have favoured, over time, the onset of different types of zoonosis. Many of these may affect many occupational categories, first of all farmers, people working in abattoirs and processing products of animal origin. New farming activities and technologies have generated new occupational and zoonotic risks. These changes have influenced zoonosis epidemiology and have led to a gradual decrease in the number of diseases and to a reduction of some biological risks. However, brucellosis, Q fever, bovine tuberculosis cystic echinococcosis remain a strong example of zoonosis and a real risk, in the Mediterranean area especially. Therefore, an interdisciplinary collaboration between Veterinary Service, Public Health and Occupational medicine is necessary in order to plan territorial prevention.

  10. Evidence for endemic chikungunya virus infections in Bandung, Indonesia.

    Directory of Open Access Journals (Sweden)

    Herman Kosasih

    Full Text Available Chikungunya virus (CHIKV is known to cause sporadic or explosive outbreaks. However, little is known about the endemic transmission of CHIKV. To ascertain the endemic occurrence of CHIKV transmission, we tested blood samples from patients with a non-dengue febrile illness who participated in a prospective cohort study of factory workers in Bandung, Indonesia. From August 2000 to June 2004, and September 2006 to April 2008, 1901 febrile episodes occurred and 231 (12.2% dengue cases were identified. The remaining febrile cases were evaluated for possible CHIKV infection by measuring anti-CHIKV IgM and IgG antibodies in acute and convalescent samples. Acute samples of serologically positive cases were subsequently tested for the presence of CHIKV RNA by RT-PCR and/or virus isolation. A total of 135 (7.1% CHIKV infections were identified, providing an incidence rate of 10.1/1,000 person years. CHIKV infections were identified all year round and tended to increase during the rainy season (January to March. Severe illness was not found and severe arthralgia was not a prominently reported symptom. Serial post-illness samples from nine cases were tested to obtain a kinetic picture of IgM and IgG anti-CHIKV antibodies. Anti-CHIKV IgM antibodies were persistently detected in high titers for approximately one year. Three patients demonstrated evidence of possible sequential CHIKV infections. The high incidence rate and continuous chikungunya cases in this adult cohort suggests that CHIKV is endemically transmitted in Bandung. Further characterization of the circulating strains and surveillance in larger areas are needed to better understand CHIKV epidemiology in Indonesia.

  11. Composition of the continental plates

    Science.gov (United States)

    Gilluly, J.

    1954-01-01

    The structures of continental plates and of oceanic basins suggested by several seismologists are utilized to estimate the relative volumes of sial and sima in the earth's crust. It seems that sial of the composition of the average igneous rock constitutes fully 26% and perhaps as much as 43% of the total crust. This ratio is far higher than seems likely if the sial had been entirely derived through fractional crystallization of a basaltic magma. The relative paucity of intermediate rocks as compared with granite and gabbro in the crust points in the same direction. The tentative conclusion is reached that the sial owes a large part of its volume to some process other than fractional crystallization of basalt-possibly to the emanation of low-melting constituents such as water, silica, potassa, soda, and alumina directly from the mantle to the crust. ?? 1954 Springer-Verlag.

  12. Deformation in the continental lithosphere

    Science.gov (United States)

    The Physical Properties of Earth Materials Committee, a technical committee of AGU's Tectonophysics Section, is organizing a dinner/colloquium as part of the Fall Meeting in San Francisco, Calif. This event will be held Monday, December 3rd, in the Gold Rush Room of the Holiday Inn Golden Gateway Hotel at 1500 Van Ness St. There will be a no-host bar from 6:30 to 7:30 P.M., followed by dinner from 7:30 to 8:30 P.M. Paul Tapponnier will deliver the after-dinner talk, “Large-Scale Deformation Mechanisms in the Continental Lithosphere: Where Do We Stand?” It will start at 8:30 P.M. and a business meeting will follow at 9:30 P.M.

  13. How Continental Bank outsourced its "crown jewels.".

    Science.gov (United States)

    Huber, R L

    1993-01-01

    No industry relies more on information than banking does, yet Continental, one of America's largest banks, outsources its information technology. Why? Because that's the best way to service the customers that form the core of the bank's business, says vice chairman Dick Huber. In the late 1970s and early 1980s, Continental participated heavily with Penn Square Bank in energy investments. When falling energy prices burst Penn Square's bubble in 1982, Continental was stuck with more than $1 billion in bad loans. Eight years later when Dick Huber came on board, Continental was working hard to restore its once solid reputation. Executives had made many tough decisions already, altering the bank's focus from retail to business banking and laying off thousands of employees. Yet management still needed to cut costs and improve services to stay afloat. Regulators, investors, and analysts were watching every step. Continental executives, eager to focus on the bank's core mission of serving business customers, decided to outsource one after another in-house service--from cafeteria services to information technology. While conventional wisdom holds that banks must retain complete internal control of IT, Continental bucked this argument when it entered into a ten-year, multimillion-dollar contract with Integrated Systems Solutions Corporation. Continental is already reaping benefits from outsourcing IT. Most important, Continental staffers today focus on their true core competencies: intimate knowledge of customers' needs and relationships with customers.

  14. Evolution of Oxidative Continental Weathering

    Science.gov (United States)

    Konhauser, Kurt; Lalonde, Stefan

    2014-05-01

    The Great Oxidation Event (GOE) is currently viewed as a protracted process during which atmospheric oxygen levels increased above 10-5 times the present atmospheric level. This value is based on the loss of sulphur isotope mass independent fractionation (S-MIF) from the rock record, beginning at 2.45 Ga and disappearing by 2.32 Ga. However, a number of recent papers have pushed back the timing for oxidative continental weathering, and by extension, the onset of atmospheric oxygenation several hundreds of million years earlier despite the presence of S-MIF (e.g., Crowe et al., 2013). This apparent discrepancy can, in part, be resolved by the suggestion that recycling of older sedimentary sulphur bearing S-MIF might have led to this signal's persistence in the rock record for some time after atmospheric oxygenation (Reinhard et al., 2013). Here we suggest another possibility, that the earliest oxidative weathering reactions occurred in environments at profound redox disequilibrium with the atmosphere, such as biological soil crusts, riverbed and estuarine sediments, and lacustrine microbial mats. We calculate that the rate of O2 production via oxygenic photosynthesis in these terrestrial microbial ecosystems provides largely sufficient oxidizing potential to mobilise sulphate and a number of redox-sensitive trace metals from land to the oceans while the atmosphere itself remained anoxic with its attendant S-MIF signature. These findings reconcile geochemical signatures in the rock record for the earliest oxidative continental weathering with the history of atmospheric sulphur chemistry, and demonstrate the plausible antiquity of a terrestrial biosphere populated by cyanobacteria. Crowe, S.A., Dossing, L.N., Beukes, N.J., Bau, M., Kruger, S.J., Frei, R. & Canfield, D.E. Atmospheric oxygenation three billion years ago. Nature 501, 535-539 (2013). Reinhard, C.T., Planavsky, N.J. & Lyons, T.W. Long-term sedimentary recycling of rare sulphur isotope anomalies. Nature 497

  15. Gravity and structure of the continental margins of southwestern Mexico and northwestern Guatemala

    Science.gov (United States)

    Couch, Richard; Woodcock, Stephen

    1981-03-01

    Geophysical measurements over the eastern end of the Tehuantepec Ridge and adjacent continental margins of southern Mexico and northern Guatemala indicate that the ridge is a fracture zone and that it marks the boundary between two different subduction provinces. A positive free-air gravity anomaly which extends northwestward along the outer continental shelf of Guatemala curves abruptly landward in the Gulf of Tehuantepec. The positive shelf anomaly is on trend with the positive anomaly of the Nicoya Peninsula, Costa Rica, and suggests that rocks genetically related to Cretaceous rocks of the Nicoya Complex extend northwestward along the continental shelf to the Gulf of Tehuantepec. A crustal and subcrustal cross section of the continental margin of Guatemala, constrained by gravity, magnetic, and seismic refraction data, indicates that the rock strata causing the outer shelf gravity high dip landward, consistent with imbricate thrusting of the oceanic crust beneath and into the continental margin. A model crustal cross section of the continental margin of southern Mexico, north of the Tehuantepec Ridge, shows a markedly different margin structure with a relatively small amount of continental accretion and a continental crustal block extending to within approximately 25 km of the trench axis.

  16. Progress towards Continental River Dynamics modeling

    Science.gov (United States)

    Yu, Cheng-Wei; Zheng, Xing; Liu, Frank; Maidment, Daivd; Hodges, Ben

    2017-04-01

    The high-resolution National Water Model (NWM), launched by U.S. National Oceanic and Atmospheric Administration (NOAA) in August 2016, has shown it is possible to provide real-time flow prediction in rivers and streams across the entire continental United States. The next step for continental-scale modeling is moving from reduced physics (e.g. Muskingum-Cunge) to full dynamic modeling with the Saint-Venant equations. The Simulation Program for River Networks (SPRNT) provides a computational approach for the Saint-Venant equations, but obtaining sufficient channel bathymetric data and hydraulic roughness is seen as a critical challenge. However, recent work has shown the Height Above Nearest Drainage (HAND) method can be applied with the National Elevation Dataset (NED) to provide automated estimation of effective channel bathymetry suitable for large-scale hydraulic simulations. The present work examines the use of SPRNT with the National Hydrography Dataset (NHD) and HAND-derived bathymetry for automated generation of rating curves that can be compared to existing data. The approach can, in theory, be applied to every stream reach in the NHD and thus provide flood guidance where none is available. To test this idea we generated 2000+ rating curves in two catchments in Texas and Alabama (USA). Field data from the USGS and flood records from an Austin, Texas flood in May 2015 were used as validation. Large-scale implementation of this idea requires addressing several critical difficulties associated with numerical instabilities, including ill-posed boundary conditions generated in automated model linkages and inconsistencies in the river geometry. A key to future progress is identifying efficient approaches to isolate numerical instability contributors in a large time-space varying solution. This research was supported in part by the National Science Foundation under grant number CCF-1331610.

  17. Modelling of temperatures in continental convergence zones

    Energy Technology Data Exchange (ETDEWEB)

    Toksoz, M.N.; Bird, P.

    1977-08-03

    The thermal histories of continent-continent convergence zones are modelled by a finite-difference technique in an attempt to explain geologic observations of heating and melting in such zones. The suture zone between two converging continents divides a passively heated overriding plate from a quiet continental margin which is suddenly deformed in the collision. Both regions may be metamorphosed and intruded. On the continental-shelf side where mountains are formed by underthrusting within the crust, it was found that adiabatic and radioactive heating are negligible during the orogeny. Shear-strain heating may raise the fault zones to about 500/sup 0/C. At higher temperatures, dislocation creep of crustal rocks would be expected from laboratory results. Even high crustal radioactivity will not produce melting in less than 40 m.y. Thus any plutons in this zone (the granites of the Zagros, Urals, and Himalayas) probably result indirectly by melting of crust that is heated by deep asthenospheric intrusions, which may reach the crust at the time of detachment of the oceanic slab, combined with the effects of friction and water along the subduction plane. Across the suture, the thermal history begins before the collision during the oceanic subduction phase. The sinking slab creates asthenospheric circulations, which warm the passive plate from below and intrude it in an Andean-type arc along the suture (Zagros and Himalayan region). If total subduction exceeds about 3000 km the slow warming has time to weaken the plate and extensive crustal shortening may follow the collision. Crustal shortening and thickening is accompanied by differentiation and volcanism (Tibetan and Grenville orogenies). Thermal modelling of Tibet shows that volcanism cannot be produced in the available time by crustal thickening alone, but requires the initial warming phase as well.

  18. 古蔺县高中生地氟病相关知识知晓情况及影响因素分析%The Survey of Risk Factors and Related Knowledge about Endemic Fluorosis of High School Students in Gulin

    Institute of Scientific and Technical Information of China (English)

    赖晋锋; 刘娅; 陈君; 陈建国; 王从林; 陈映翰; 叶运莉

    2015-01-01

    Objective :To understand the health education present situation and the demand about the Endemic Fluoro‐sis Prevention in Gulin county which could provide the basis for controlling endemic fluorosis .Methods :A total of 748 High school students in Gulin ,were chosen under Stratified cluster random sampling and had completed a question‐naire survey related with fluorosis knowledge .Results:The awareness rate of endemic fluorosis of the participants was 57 .95% .The awareness of the lowest three points“the performance of severe skeletal fluorosis (7 .6% )” ,“the height of health stoves above the roof (21 .8% )” ,“the main performance of the endemic fluorosis (26 .3% )”;Students of en‐demic fluorosis prevention knowledge sources accounts are publicity column ,leaflets (62 .3% ) ,radio/TV (38 .4% ) , the school teachers (34 .5% ) . The hopeful way for the top three are doctors (64 .9% ) ,publicity column ,flyer (55.8% ) ,radio/TV (47 .1% ) .Conclusion:The high school students in Gulin county of Sichuan endemic fluorosis pre‐vention knowledge awareness rate is very low ,less access to health knowledge ,and there is an urgent need to strength‐en the publicity health education and the popularization work .%目的:了解古蔺县地氟病区高中生燃煤型地氟病防治健康教育现状及需求,为地氟病进一步防治提供依据。方法:通过分层整群随机抽样的方法抽取古蔺县地氟病区748名高中生,对其进行问卷调查。结果:调查对象地氟病防治知识总知晓率为57.95%;知晓率最低的三个知识点分别是“严重氟骨症引起的表现(7.6%)”、“卫生炉灶高出屋脊的高度(21.8%)”、“地氟病主要表现(26.3%)”;调查对象目前地氟病防治知识来源占前三位的分别是宣传栏、宣传单(62.3%),广播/电视(38.4%),学校老师(34.5%)。学生希望获得地氟病的防治

  19. 75 FR 61512 - Outer Continental Shelf Official Protraction Diagrams

    Science.gov (United States)

    2010-10-05

    ... Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf Official... Outer Continental Shelf Official Protraction Diagrams (OPDs) located within Atlantic Ocean areas, with... informational purposes only. Outer Continental Shelf Official Protraction Diagrams in the North Atlantic,...

  20. Estimating the global volume of deeply recycled continental crust at continental collision zones

    Science.gov (United States)

    Scholl, D. W.; Huene, R. V.

    2006-12-01

    CRUSTAL RECYCLING AT OCEAN MARGINS: Large volumes of rock and sediment are missing from the submerged forearcs of ocean margin subduction zones--OMSZs. This observation means that (1) oceanic sediment is transported beneath the margin to either crustally underplate the coastal region or reach mantle depths, and that (2) the crust of the forearc is vertically thinned and horizontally truncated and the removed material transported toward the mantle. Transport of rock and sediment debris occurs in the subduction channel that separates the upper and lower plates. At OMSZs the solid-volume flux of recycling crustal material is estimated to be globally ~2.5 km3/yr (i.e., 2.5 Armstrong units or AU). The corresponding rate of forearc truncation (migration of the trench axis toward a fix reference on the continent) is a sluggish 2-3 km/Myr (about 1/50th the orthogonal convergence rate). Nonetheless during the past 2.5 Gyr (i.e., since the beginning of the Proterozoic) a volume of continental material roughly equal to the existing volume (~7 billion cubic km) has been recycled to the mantle at OMSZs. The amount of crust that has been destroyed is so large that recycling must have been a major factor creating the mapped rock pattern and age-fabric of continental crust. RECYCLING AT CONTINENT/ARC COLLISIONS: The rate at which arc magmatism globally adds juvenile crust to OMSZs has been commonly globally estimated at ~1 AU. But new geophysical and dating information from the Aleutian and IBM arcs imply that the addition rate is at least ~5 AU (equivalent to ~125 km3/Myr/km of arc). If the Armstrong posit is correct that since the early Archean a balance has existed between additions and losses of crust, then a recycling sink for an additional 2-3 AU of continental material must exist. As the exposure of exhumed masses of high P/T blueschist bodies documents that subcrustal streaming of continental material occurs at OMSZs, so does the occurrence of exhumed masses of UHP

  1. Endemic epigean Tenebrionids (Coleoptera: Tenebrionidae) from the Andean Region: exploring the patagonian-diversification hypothesis.

    Science.gov (United States)

    Carrara, Rodolfo; Flores, Gustavo E

    2015-08-26

    Tenebrionidae is a diverse insect family of Coleoptera that shows high levels of endemicity in epigean species. For the Andean region, which is divided into three subregions: Central Chilean, Subantarctic and Patagonian, it has been hypothesized that epigean tenebrionids have diversified in the Patagonian subregion and subsequently, they dispersed to Subantarctic and Central Chilean subregions. In this work, based on information obtained from museum collections and scientific studies, we presented the first list of endemic epigean tenebrionids from the Andean region with their taxonomic arrangement and geographic distribution. Moreover, we used these data to explore the veracity of the Patagonian-diversification hypothesis. A total of 416 species grouped into six subfamilies, 17 tribes and 41 genera were identified as endemic to the Andean region. Considering the spatial distribution it was observed that subfamilies, tribes, genera and species were unequally distributed across subregions. Results did not support the Patagonian-diversification hypothesis; to the contrary, they were more concordant with processes of isolation among subregions that have promoted speciation by interrupting gene flow among populations, resulting in endemism because species can not expand their range sizes. Finally, we discuss the implications of our findings to be considered in biodiversity conservation, because endemic species, by their high extinction risk, are primary targets in conservation strategies.

  2. The Roles of Advection and In Situ Growth in Determining the Dynamics of Continental Shelf Zooplankton: High Frequency Measurements of Zooplankton Biomass Coupled with Measurements of Secondary Productivity in the Middle Atlantic Bight

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Sharon L.

    1999-03-26

    Evaluation of the role of continental margins in planetary carbon cycles can be approached in various ways, with the extremes being knowledge generated either by large-scale studies of a few basic characteristics of the carbon cycle of shelves worldwide (comparative approach) or by temporally intensive studies of a few sites selected to typify contrasting processes. Mechanisms of cross-shelf transfer, for example, are presently of great interest and within the US there are at least four differing continental shelf environments in which cross-shelf processes are driven by storms (southern Bering Sea, northeastern US), by jets and eddies (northern California coast), by freshwater runoff (Bering Sea, Gulf of Mexico), and by frontal meanders and filaments of the Gulf Stream (southeastern US). Because the type and magnitude of the physical forcing, and its variability on an annual scale, are fundamental to the response of the carbon cycle, investigation of each of these shelves would offer insight useful to predictive global understanding of the carbon cycle on continental shelves.

  3. Tectonic erosion, subduction accretion and arc collision as controls on the growth of the continental crust

    Science.gov (United States)

    Clift, P.; Vannucchi, P.; Draut, A.

    2003-04-01

    Subduction plate boundaries, at which tectonic erosion removes material from the overriding plate, account for 57% of the total length of the global subduction system and are favored where convergence rates exceed 7 cm/yr and where the sedimentary cover is less than 1 km. Accretion conversely preferentially occurs in regions of slow convergence (1 km. The slope gradients and taper angle of accretionary plate margins correlates with plate convergence rates, while erosive margin slopes appear to be independent of this. Rates of trench retreat do not appear to correlate with any simple characteristic of the plate interaction, but are largely a function of the history of seamount or ridge collisions. Mass balances of the global subduction system indicate that the entire volume of the continental crust can be recycled through the subduction system every 2.6 Ga. Even in accretionary margins a median of only 32% of the incoming sedimentary mass is accreted over time scales of 10 my or greater, resulting in long-term net loss of continental crust along continental active margins. Average magmatic productivity in the active margins must exceed 75 km3/my if the volume of the continental crust is to reach the slow growth rate indicated by isotopic and continental freeboard arguments. Geological arguments indicate that magmatic accretion rates must be faster in oceanic arcs (87-95 km3/my) and less in the continental arcs (65-83 km3/my). Mass balance arguments in oceanic arcs require that their crustal thicknesses must be Continental growth is principally achieved through the collision of oceanic island arcs to continental margins. Although oceanic arcs are chemically distinct from continental crust, the collision process involves the loss of mafic and ultramafic lower crust and the emplacement of voluminous, high silica, light rare earth element enriched melts, transforming the net composition into something more continental in character.

  4. Influence of Earth crust composition on continental collision style in Precambrian conditions: Results of supercomputer modelling

    Science.gov (United States)

    Zavyalov, Sergey; Zakharov, Vladimir

    2016-04-01

    A number of issues concerning Precambrian geodynamics still remain unsolved because of uncertainity of many physical (thermal regime, lithosphere thickness, crust thickness, etc.) and chemical (mantle composition, crust composition) parameters, which differed considerably comparing to the present day values. In this work, we show results of numerical supercomputations based on petrological and thermomechanical 2D model, which simulates the process of collision between two continental plates, each 80-160 km thick, with various convergence rates ranging from 5 to 15 cm/year. In the model, the upper mantle temperature is 150-200 ⁰C higher than the modern value, while the continental crust radiogenic heat production is higher than the present value by the factor of 1.5. These settings correspond to Archean conditions. The present study investigates the dependence of collision style on various continental crust parameters, especially on crust composition. The 3 following archetypal settings of continental crust composition are examined: 1) completely felsic continental crust; 2) basic lower crust and felsic upper crust; 3) basic upper crust and felsic lower crust (hereinafter referred to as inverted crust). Modeling results show that collision with completely felsic crust is unlikely. In the case of basic lower crust, a continental subduction and subsequent continental rocks exhumation can take place. Therefore, formation of ultra-high pressure metamorphic rocks is possible. Continental subduction also occurs in the case of inverted continental crust. However, in the latter case, the exhumation of felsic rocks is blocked by upper basic layer and their subsequent interaction depends on their volume ratio. Thus, if the total inverted crust thickness is about 15 km and the thicknesses of the two layers are equal, felsic rocks cannot be exhumed. If the total thickness is 30 to 40 km and that of the felsic layer is 20 to 25 km, it breaks through the basic layer leading to

  5. Análisis biogeográfico de la diversidad pteridofítica en Argentina y Chile continental Biogeographical analysis of the pteridophyte diversity of continental Argentina and Chile

    Directory of Open Access Journals (Sweden)

    MÓNICA PONCE

    2002-12-01

    , y que sus límites han retrocedido a causa de los impactantes cambios climáticos y geomorfológicos que sucedieron durante el Terciario y el Pleistoceno.The pteridophytes are represented by 116 native species (43 genera/20 families in continental Chile, and by 346 native species (86 genera/27 families in continental Argentina. Both countries share 89 species (41 genera/20 families. Lower pteridophyte diversity and the higher endemism in Chile (11.2 % than in Argentina (3.5 % are possibly related to historical extinctions and the actual geo-climatic isolation. However, the endemism in pteridophytes is five to six times lower than in angiosperms. The richest Argentinean genera are Thelypteris (34 species, Asplenium (32, Cheilanthes (21, Blechnum (19 and Hymenophyllum (16. The last two genera are also the most numerous in Chile (Hymenophyllum 18 species and Blechnum 10. In the two countries, pteridophyte diversity shows opposite latitudinal trends, with high species richness in three centers: two subtropical humid centers in northwestern and northeastern Argentina, and a temperate humid center in southern Chile and Argentina around 40º S. The three centers concentrate 93 % of the species and 95 % of the endemisms, sharing few species. In the subtropical centers, the families Aspleniaceae, Polypodiaceae, Pteridaceae, Thelypteridaceae and Selaginellaceae are the main components and share a large number of species with Bolivia and Brazil, respectively. The southern temperate center has a lower pteridophyte diversity, but a larger number of endemisms (77 % than the northern subtropical centers. However, adjacent regions of Chile and Argentina within the temperate center have high similarity and maintain a strong floristic interchange. Blechnaceae and Hymenophyllaceae are the most common families. Taxa with disjunct distribution patterns and with presence in the three centers indicate that the pteridophyte flora had a wider and continuous distribution in the past, and

  6. Plasmodium falciparum Malaria Endemicity in Indonesia in 2010

    Science.gov (United States)

    Elyazar, Iqbal R. F.; Gething, Peter W.; Patil, Anand P.; Rogayah, Hanifah; Kusriastuti, Rita; Wismarini, Desak M.; Tarmizi, Siti N.; Baird, J. Kevin; Hay, Simon I.

    2011-01-01

    Background Malaria control programs require a detailed understanding of the contemporary spatial distribution of infection risk to efficiently allocate resources. We used model based geostatistics (MBG) techniques to generate a contemporary map of Plasmodium falciparum malaria risk in Indonesia in 2010. Methods Plasmodium falciparum Annual Parasite Incidence (PfAPI) data (2006–2008) were used to map limits of P. falciparum transmission. A total of 2,581 community blood surveys of P. falciparum parasite rate (PfPR) were identified (1985–2009). After quality control, 2,516 were included into a national database of age-standardized 2–10 year old PfPR data (PfPR2–10) for endemicity mapping. A Bayesian MBG procedure was used to create a predicted surface of PfPR2–10 endemicity with uncertainty estimates. Population at risk estimates were derived with reference to a 2010 human population count surface. Results We estimate 132.8 million people in Indonesia, lived at risk of P. falciparum transmission in 2010. Of these, 70.3% inhabited areas of unstable transmission and 29.7% in stable transmission. Among those exposed to stable risk, the vast majority were at low risk (93.39%) with the reminder at intermediate (6.6%) and high risk (0.01%). More people in western Indonesia lived in unstable rather than stable transmission zones. In contrast, fewer people in eastern Indonesia lived in unstable versus stable transmission areas. Conclusion While further feasibility assessments will be required, the immediate prospects for sustained control are good across much of the archipelago and medium term plans to transition to the pre-elimination phase are not unrealistic for P. falciparum. Endemicity in areas of Papua will clearly present the greatest challenge. This P. falciparum endemicity map allows malaria control agencies and their partners to comprehensively assess the region-specific prospects for reaching pre-elimination, monitor and evaluate the effectiveness of

  7. A review of contemporary patterns of endemism for shallow water reef fauna in the Red Sea

    KAUST Repository

    DiBattista, Joseph

    2015-11-03

    Aim The Red Sea is characterised by a unique fauna and historical periods of desiccation, hypersalinity and intermittent isolation. The origin and contemporary composition of reef-associated taxa in this region can illuminate biogeographical principles about vicariance and the establishment (or local extirpation) of existing species. Here we aim to: (1) outline the distribution of shallow water fauna between the Red Sea and adjacent regions, (2) explore mechanisms for maintaining these distributions and (3) propose hypotheses to test these mechanisms. Location Red Sea, Gulf of Aden, Arabian Sea, Arabian Gulf and Indian Ocean. Methods Updated checklists for scleractinian corals, fishes and non-coral invertebrates were used to determine species richness in the Red Sea and the rest of the Arabian Peninsula and assess levels of endemism. Fine-scale diversity and abundance of reef fishes within the Red Sea were explored using ecological survey data. Results Within the Red Sea, we recorded 346 zooxanthellate and azooxanthellate scleractinian coral species of which 19 are endemic (5.5%). Currently 635 species of polychaetes, 211 echinoderms and 79 ascidians have been documented, with endemism rates of 12.6%, 8.1% and 16.5% respectively. A preliminary compilation of 231 species of crustaceans and 137 species of molluscs include 10.0% and 6.6% endemism respectively. We documented 1071 shallow fish species, with 12.9% endemic in the entire Red Sea and 14.1% endemic in the Red Sea and Gulf of Aden. Based on ecological survey data of endemic fishes, there were no major changes in species richness or abundance across 1100 km of Saudi Arabian coastline. Main conclusions The Red Sea biota appears resilient to major environmental fluctuations and is characterized by high rates of endemism with variable degrees of incursion into the Gulf of Aden. The nearby Omani and Arabian Gulfs also have variable environments and high levels of endemism, but these are not consistently distinct

  8. Genetic and morphological analyses indicate that the Australian endemic scorpion Urodacus yaschenkoi (Scorpiones: Urodacidae) is a species complex

    Science.gov (United States)

    Luna-Ramirez, Karen; Miller, Adam D.

    2017-01-01

    Background Australian scorpions have received far less attention from researchers than their overseas counterparts. Here we provide the first insight into the molecular variation and evolutionary history of the endemic Australian scorpion Urodacus yaschenkoi. Also known as the inland robust scorpion, it is widely distributed throughout arid zones of the continent and is emerging as a model organism in biomedical research due to the chemical nature of its venom. Methods We employed Bayesian Inference (BI) methods for the phylogenetic reconstructions and divergence dating among lineages, using unique haplotype sequences from two mitochondrial loci (COXI, 16S) and one nuclear locus (28S). We also implemented two DNA taxonomy approaches (GMYC and PTP/dPTP) to evaluate the presence of cryptic species. Linear Discriminant Analysis was used to test whether the linear combination of 21 variables (ratios of morphological measurements) can predict individual’s membership to a putative species. Results Genetic and morphological data suggest that U. yaschenkoi is a species complex. High statistical support for the monophyly of several divergent lineages was found both at the mitochondrial loci and at a nuclear locus. The extent of mitochondrial divergence between these lineages exceeds estimates of interspecific divergence reported for other scorpion groups. The GMYC model and the PTP/bPTP approach identified major lineages and several sub-lineages as putative species. Ratios of several traits that approximate body shape had a strong predictive power (83–100%) in discriminating two major molecular lineages. A time-calibrated phylogeny dates the early divergence at the onset of continental-wide aridification in late Miocene and Pliocene, with finer-scale phylogeographic patterns emerging during the Pleistocene. This structuring dynamics is congruent with the diversification history of other fauna of the Australian arid zones. Discussion Our results indicate that the

  9. Potential evapotranspiration and continental drying

    Science.gov (United States)

    Milly, P. C. D.; Dunne, K. A.

    2016-10-01

    By various measures (drought area and intensity, climatic aridity index, and climatic water deficits), some observational analyses have suggested that much of the Earth’s land has been drying during recent decades, but such drying seems inconsistent with observations of dryland greening and decreasing pan evaporation. `Offline’ analyses of climate-model outputs from anthropogenic climate change (ACC) experiments portend continuation of putative drying through the twenty-first century, despite an expected increase in global land precipitation. A ubiquitous increase in estimates of potential evapotranspiration (PET), driven by atmospheric warming, underlies the drying trends, but may be a methodological artefact. Here we show that the PET estimator commonly used (the Penman-Monteith PET for either an open-water surface or a reference crop) severely overpredicts the changes in non-water-stressed evapotranspiration computed in the climate models themselves in ACC experiments. This overprediction is partially due to neglect of stomatal conductance reductions commonly induced by increasing atmospheric CO2 concentrations in climate models. Our findings imply that historical and future tendencies towards continental drying, as characterized by offline-computed runoff, as well as other PET-dependent metrics, may be considerably weaker and less extensive than previously thought.

  10. Population connectivity and the effectiveness of marine protected areas to protect vulnerable, exploited and endemic coral reef fishes at an endemic hotspot

    KAUST Repository

    Van Der Meer, Martin H.

    2014-12-23

    Marine protected areas (MPAs) aim to mitigate anthropogenic impacts by conserving biodiversity and preventing overfishing. The effectiveness of MPAs depends on population connectivity patterns between protected and non-protected areas. Remote islands are endemism hotspots for coral reef fishes and provide rare examples of coral reefs with limited fishing pressure. This study explored population genetic connectivity across a network of protected and non-protected areas for the endemic wrasse, Coris bulbifrons, which is listed as “vulnerable” by the IUCN due to its small, decreasing geographic range and declining abundance. Mitochondrial DNA (mtDNA) and microsatellite DNA (msatDNA) markers were used to estimate historic and contemporary gene flow to determine the level of population self-replenishment and to measure genetic and genotypic diversity among all four locations in the species range (south-west Pacific Ocean)—Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI) and Norfolk Island (NI). MPAs exist at MR and LHI and are limited or non-existent at ER and NI, respectively. There was no obvious differentiation in mtDNA among locations, however, msatDNA revealed differentiation between the most peripheral (NI) and all remaining locations (MR, ER and LHI). Despite high mtDNA connectivity (M = 259–1,144), msatDNA connectivity was limited (M = 3–9) with high self-replenishment (68–93 %) at all locations. NI is the least connected and heavily reliant on self-replenishment, and the absence of MPAs at NI needs to be rectified to ensure the persistence of endemic species at this location. Other endemic fishes exhibit similar patterns of high self-replenishment across the four locations, indicating that a single spatial management approach consisting of a MPA network protecting part of each location could provide reasonable protection for these species. Thus, the existing network of MPAs at this endemic hotspot appears adequate at some locations

  11. Population connectivity and the effectiveness of marine protected areas to protect vulnerable, exploited and endemic coral reef fishes at an endemic hotspot

    Science.gov (United States)

    van der Meer, M. H.; Berumen, M. L.; Hobbs, J.-P. A.; van Herwerden, L.

    2015-06-01

    Marine protected areas (MPAs) aim to mitigate anthropogenic impacts by conserving biodiversity and preventing overfishing. The effectiveness of MPAs depends on population connectivity patterns between protected and non-protected areas. Remote islands are endemism hotspots for coral reef fishes and provide rare examples of coral reefs with limited fishing pressure. This study explored population genetic connectivity across a network of protected and non-protected areas for the endemic wrasse, Coris bulbifrons, which is listed as "vulnerable" by the IUCN due to its small, decreasing geographic range and declining abundance. Mitochondrial DNA (mtDNA) and microsatellite DNA (msatDNA) markers were used to estimate historic and contemporary gene flow to determine the level of population self-replenishment and to measure genetic and genotypic diversity among all four locations in the species range (south-west Pacific Ocean)—Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI) and Norfolk Island (NI). MPAs exist at MR and LHI and are limited or non-existent at ER and NI, respectively. There was no obvious differentiation in mtDNA among locations, however, msatDNA revealed differentiation between the most peripheral (NI) and all remaining locations (MR, ER and LHI). Despite high mtDNA connectivity ( M = 259-1,144), msatDNA connectivity was limited ( M = 3-9) with high self-replenishment (68-93 %) at all locations. NI is the least connected and heavily reliant on self-replenishment, and the absence of MPAs at NI needs to be rectified to ensure the persistence of endemic species at this location. Other endemic fishes exhibit similar patterns of high self-replenishment across the four locations, indicating that a single spatial management approach consisting of a MPA network protecting part of each location could provide reasonable protection for these species. Thus, the existing network of MPAs at this endemic hotspot appears adequate at some locations, but not

  12. Consanguineous marriages and endemic malaria: can inbreeding increase population fitness?

    Directory of Open Access Journals (Sweden)

    Nagelkerke Nicolas

    2008-08-01

    Full Text Available Abstract Background The practice of consanguineous marriages is widespread in countries with endemic malaria. In these regions, consanguinity increases the prevalence of α+-thalassemia, which is protective against malaria. However, it also causes an excessive mortality amongst the offspring due to an increase in homozygosis of recessive lethal alleles. The aim of this study was to explore the overall effects of inbreeding on the fitness of a population infested with malaria. Methods In a stochastic computer model of population growth, the sizes of inbred and outbred populations were compared. The model has been previously validated producing results for inbred populations that have agreed with analytical predictions. Survival likelihoods for different α+-thalassemia genotypes were obtained from the odds of severe forms of disease from a field study. Survivals were further estimated for different values of mortality from malaria. Results Inbreeding increases the frequency of α+-thalassemia allele and the loss of life due to homozygosis of recessive lethal alleles; both are proportional to the coefficient of inbreeding and the frequency of alleles in population. Inbreeding-mediated decrease in mortality from malaria (produced via enhanced α+-thalassemia frequency mitigates inbreeding-related increases in fatality (produced via increased homozygosity of recessive lethals. When the death rate due to malaria is high, the net effect of inbreeding is a reduction in the overall mortality of the population. Conclusion Consanguineous marriages may increase the overall fitness of populations with endemic malaria.

  13. Etiology of Balkan endemic nephropathy and associated urothelial cancer

    Energy Technology Data Exchange (ETDEWEB)

    Stefanovic, V.; Toncheva, D.; Atanasova, S.; Polenakovic, M. [Inst. of Nephrology and Hemodialysis, Nish (Serbia Montenegro)

    2006-07-01

    Balkan endemic nephropathy (BEN) is a familial chronic tubulointerstitial disease with insidious onset and slow progression to terminal renal failure. Evidence has accumulated that BEN is an environmentally induced disease. There are three actual theories attempting to explain the environmental cause of this disease: (1) the aristolochic acid hypothesis, which considers that the disease is produced by chronic intoxication with Aristolochia, (2) the mycotoxin hypothesis, which considers that BEN is produced by ochratoxin A, and (3) the Pliocene lignite hypothesis, which proposes that the disease is caused by long-term exposure to polycyclic aromatic hydrocarbons and other toxic organic compounds leaching into the well drinking water from low-rank coals in the vicinity to the endemic settlements. Moreover, it was suggested that BEN risk is influenced by inherited susceptibility. Therefore, it has been expected that molecular biological investigations will discover genetic markers of BEN and associated urothelial cancer, permitting early identification of susceptible individuals who may be at risk of exposure to the environmental agents. Since kidney pathophysiology is complex, gene expression analysis and highly throughput proteomic technology can identify candidate genes, proteins and molecule networks that eventually could play a role in BEN development. Investigation of gene-gene and gene-environment interactions could be the content of further studies determining the precise risk for BEN.

  14. Detection of human taeniases in Tibetan endemic areas, China.

    Science.gov (United States)

    Li, Tiaoying; Chen, Xingwang; Yanagida, Tetsuya; Wang, Hao; Long, Changping; Sako, Yasuhito; Okamoto, Munehir; Wu, Yunfei; Giraudoux, Patrick; Raoul, Francis; Nkouawa, Agathe; Nakao, Minoru; Craig, Philip S; Ito, Akira

    2013-11-01

    Detection of taeniasis carriers of Taenia solium is essential for control of cysticercosis in humans and pigs. In the current study, we assessed the positive detection rate of a self-detection tool, stool microscopy with direct smear and coproPCR for taeniasis carriers in endemic Tibetan areas of northwest Sichuan. The self-detection tool through questioning about a history of proglottid expulsion within the previous one year showed an overall positive detection rate of more than 80% for Taenia saginata, T. solium and T. asiatica. The positive detection rate was similar for T. saginata and T. solium. In 132 taeniid tapeworm carriers, 68 (51·5%) were detected by microscopy and 92 (69·7%) were diagnosed by coproPCR. A combination of microscopy and coproPCR increased the positive detection rate to 77·3%. There remained 10 cases (7·6%) coproPCR negative but microscopy positive. Due to the high cost and complicated process, coproPCR is required for the identification of Taenia species only when necessary, though it had a significant higher positive detection rate than microscopy. Combined use of self-detection and stool microscopy are recommended in community-based mass screening for taeniases in this Tibetan area or in other situation-similar endemic regions.

  15. Atlantic NAD 83 Continental Shelf Boundary (CSB)

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains Continental Shelf Boundary (CSB) lines in ESRI shapefile format for the BOEM Atlantic Region. The CSB defines the seaward limit of federally...

  16. Continental Shelf Boundary - Alaska NAD83

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — This data set contains Continental Shelf Boundaries (CSB) lines in ESRI shapefile format for the BOEM Alaska Region. The CSB defines the seaward limit of federally...

  17. Volatile components and continental material of planets

    Science.gov (United States)

    Florenskiy, K. P.; Nikolayeva, O. V.

    1986-01-01

    It is shown that the continental material of the terrestrial planets varies in composition from planet to planet according to the abundances and composition of true volatiles (H20, CO2, etc.) in the outer shells of the planets. The formation of these shells occurs very early in a planet's evolution when the role of endogenous processes is indistinct and continental materials are subject to melting and vaporizing in the absence of an atmosphere. As a result, the chemical properties of continental materials are related not only to fractionation processes but also to meltability and volatility. For planets retaining a certain quantity of true volatile components, the chemical transformation of continental material is characterized by a close interaction between impact melting vaporization and endogeneous geological processes.

  18. Exploration of the continental margins of India

    Digital Repository Service at National Institute of Oceanography (India)

    Siddiquie, H.N.; Hashimi, N.H.; Vora, K.H.; Pathak, M.C.

    In mid 1970's the National Institute of Oceanography, Goa, India prepared a plan for systematic regional, geological and geophysical surveys of the continental margins of India. This involved over 75,000 km of underway (bathymetric, side scan sonar...

  19. Co-endemicity of Cysticercosis and Schistosomiasis in Africa - how many people are at risk?

    DEFF Research Database (Denmark)

    Saarnak, Christopher; Braae, Uffe Christian; Magnussen, Pascal

    The World Health Organisation (WHO) is aiming for elimination of schistosomiasis by 2020 through mass drug administration (MDA). However, the drug used for this, praziquantel, has been reported to cause dramatic side effects, even death, among people suffering from neurocysticercosis (NCC). Both...... in co-endemic districts. Over 135 million people live in co-endemic areas. Of these, almost 44 million live in high prevalence areas for schistosomiasis where WHO recommend MDA for the entire population. In co-endemic areas resources need to be allocated for evaluating the extent of adverse effects...... caused by mass drug administration in areas where people suffer from neurocysticercosis. One Health control strategies should be implemented, monitored and evaluated to enhance disease control with a long-term goal of elimination....

  20. Principles of the continental copyright law

    OpenAIRE

    Matveev A.

    2016-01-01

    It is known that there are two key copyright law traditions: English–American and Roman–Germanic copyright laws. The French and German copyright law is in the vanguard of the continental copyright law, with the copyright law of Russia being among the others in this copyright law system. However, the Russian copyright law has some specific characteristics. Copyright law is based on the defined principles. The purpose of the present article is to define the principles Continental Copyright Law....

  1. Continental underplating after slab break-off

    Science.gov (United States)

    Magni, V.; Allen, M. B.; van Hunen, J.; Bouilhol, P.

    2017-09-01

    We present three-dimensional numerical models to investigate the dynamics of continental collision, and in particular what happens to the subducted continental lithosphere after oceanic slab break-off. We find that in some scenarios the subducting continental lithosphere underthrusts the overriding plate not immediately after it enters the trench, but after oceanic slab break-off. In this case, the continental plate first subducts with a steep angle and then, after the slab breaks off at depth, it rises back towards the surface and flattens below the overriding plate, forming a thick horizontal layer of continental crust that extends for about 200 km beyond the suture. This type of behaviour depends on the width of the oceanic plate marginal to the collision zone: wide oceanic margins promote continental underplating and marginal back-arc basins; narrow margins do not show such underplating unless a far field force is applied. Our models show that, as the subducted continental lithosphere rises, the mantle wedge progressively migrates away from the suture and the continental crust heats up, reaching temperatures >900 °C. This heating might lead to crustal melting, and resultant magmatism. We observe a sharp peak in the overriding plate rock uplift right after the occurrence of slab break-off. Afterwards, during underplating, the maximum rock uplift is smaller, but the affected area is much wider (up to 350 km). These results can be used to explain the dynamics that led to the present-day crustal configuration of the India-Eurasia collision zone and its consequences for the regional tectonic and magmatic evolution.

  2. Mechanisms of continental intraplate earthquakes

    Science.gov (United States)

    Gangopadhyay, Abhijit Kumar

    To better understand the mechanisms of continental intraplate earthquakes, a multistep approach was used. The first step involved analysis and synthesis of multidisciplinary data from 39 intraplate earthquakes spanning 20 continental intraplate regions, to identify their characteristic and diagnostic features. This led to the following testable hypothesis: Intraplate earthquakes occur within pre-existing zones of weakness (most commonly failed rifts), in the vicinity of stress concentrators, such as, intersecting faults, buried plutons, and/or rift pillows in the presence of the ambient stress field. The next step involved testing this hypothesis---first with 2-D mechanical models and then with 3-D models. Since two-thirds of the examined intraplate regions had intersecting faults as a stress concentrator, its role was first evaluated. A Distinct Element Method was used wherein the models comprised of the structural framework of the concerned region represented by a set of rock blocks that are assigned elastic properties conforming to the known geology, and subjected to tectonic loading along the direction of maximum regional compression (S Hmax) at a rate similar to the ambient plate velocity. The 2-D modeling was performed for two major intraplate regions in eastern U.S., viz., New Madrid and Middleton Place Summerville seismic zones, using a commercially available code called UDEC. These models adequately explain the spatial distribution of current seismicity in the regions. However, the absence of the third dimension limited the observation of tectonics in the depth dimension. Thus, 3-D models were developed for these two regions using the 3-D version of UDEC, called 3DEC. The preliminary results of these models adequately demonstrate correlation of locations of current seismicity with fault intersections in 3-D space, and also duplicate vertical movements. Although, the mechanical models demonstrated a causal association of seismicity with intersecting faults

  3. Spatial segregation of the endemic versus non-endemic hummingbird on Robinson Crusoe Island, Chile

    DEFF Research Database (Denmark)

    Vizentin-Bugoni, Jeferson; Sonne, Jesper; Hodum, Peter

    2017-01-01

    Competitive pressure from invasive species tends to have a particularly strong impact on remote islands, and knowledge of such phenomena can be crucial to the conservation of endemic biodiversity. Of the two hummingbird species inhabiting Robinson Crusoe Island, Juan Fernández Archipelago, Chile...

  4. The Continental Crust: A Geophysical Approach

    Science.gov (United States)

    Christensen, Nikolas I.

    Nearly 80 years ago, Yugoslavian seismologist Andrija Mohorovicic recognized, while studying a Balkan earthquake, that velocities of seismic waves increase abruptly at a few tens of kilometers depth , giving rise to the seismological definition of the crust. Since that discovery, many studies concerned with the nature of both the continental and oceanic crusts have appeared in the geophysical literature.Recently, interest in the continental crust has cascaded. This is largely because of an infusion of new data obtained from major reflection programs such as the Consortium for Continental Reflection Profiling (COCORP) and British Institutions Reflection Profiling Syndicate (BIRPS) and increased resolution of refraction studies. In addition, deep continental drilling programs are n ow in fashion. The Continental Crust: A Geophysical Approach is a summary of present knowledge of the continental crust. Meissner has succeeded in writing a book suited to many different readers, from the interested undergraduate to the professional. The book is well documented , with pertinent figures and a complete and up-to-date reference list.

  5. Continental crust generated in oceanic arcs

    Science.gov (United States)

    Gazel, Esteban; Hayes, Jorden L.; Hoernle, Kaj; Kelemen, Peter; Everson, Erik; Holbrook, W. Steven; Hauff, Folkmar; van den Bogaard, Paul; Vance, Eric A.; Chu, Shuyu; Calvert, Andrew J.; Carr, Michael J.; Yogodzinski, Gene M.

    2015-04-01

    Thin oceanic crust is formed by decompression melting of the upper mantle at mid-ocean ridges, but the origin of the thick and buoyant continental crust is enigmatic. Juvenile continental crust may form from magmas erupted above intra-oceanic subduction zones, where oceanic lithosphere subducts beneath other oceanic lithosphere. However, it is unclear why the subduction of dominantly basaltic oceanic crust would result in the formation of andesitic continental crust at the surface. Here we use geochemical and geophysical data to reconstruct the evolution of the Central American land bridge, which formed above an intra-oceanic subduction system over the past 70 Myr. We find that the geochemical signature of erupted lavas evolved from basaltic to andesitic about 10 Myr ago--coincident with the onset of subduction of more oceanic crust that originally formed above the Galápagos mantle plume. We also find that seismic P-waves travel through the crust at velocities intermediate between those typically observed for oceanic and continental crust. We develop a continentality index to quantitatively correlate geochemical composition with the average P-wave velocity of arc crust globally. We conclude that although the formation and evolution of continents may involve many processes, melting enriched oceanic crust within a subduction zone--a process probably more common in the Archaean--can produce juvenile continental crust.

  6. Estimation of Future PM2.5- and Ozone-related Mortality over the Continental United States in a Changing Climate: An application of High-resolution Dynamical Downscaling Technique

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jian; Fu, Joshua S.; Huang, Kan; Gao, Yang

    2015-04-14

    This paper evaluates the PM2.5- and ozone-related mortality at present (2000s) and in the future (2050s) over the continental United States by using the Environmental Benefits Mapping and Analysis Program (BenMAP-CE). Atmospheric chemical fields are simulated by WRF/CMAQ (horizontal resolution: 12 × 12km), applying the dynamical downscaling technique from global climate-chemistry models under the Representative Concentration Pathways scenario (RCP 8.5). Future air quality results predict that the annual mean PM2.5 concentrations in continental US will decrease nationwide, especially in the eastern US and west coast. However, the ozone concentration is projected to decrease in the Eastern US but increase in the Western US. Future mortality is evaluated under two scenarios (1) holding future population and baseline incidence rate at the present level and (2) decreasing the future baseline incidence rate but increasing the future population. For PM2.5, the entire continental US presents a decreasing trend of PM2.5-related mortality by the 2050s in Scenario (1), primarily resulting from the emissions reduction. While in Scenario (2), almost half of the continental states show a rising tendency of PM2.5-related mortality, due to the dominant influence of population growth. In particular, the highest PM2.5-related deaths and the biggest discrepancy between present and future PM2.5-related deaths will both occur in California in 2050s. For the ozone-related premature mortality, the simulation shows nation-wide rising tendency in 2050s under both two scenarios, mainly due to the increase of ozone concentration and population in the future. Furthermore, the uncertainty analysis shows that the effect of the all causes mortality is much larger than for specific causes. This assessment is the result of the accumulated uncertainty of generating datasets. The uncertainty range of ozone-related all cause premature mortality is narrower than the PM2.5-related all cause mortality

  7. Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

    Science.gov (United States)

    Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

    2014-01-01

    Crayfishes and other freshwater aquatic fauna are particularly at risk globally due to anthropogenic demand, manipulation and exploitation of freshwater resources and yet are often understudied. The Ozark faunal region of Missouri and Arkansas harbours a high level of aquatic biological diversity, especially in regard to endemic crayfishes. Three such endemics, Orconectes eupunctus,Orconectes marchandi and Cambarus hubbsi, are threatened by limited natural distribution and the invasions of Orconectes neglectus.

  8. Childhood Leprosy in an Endemic Area of Central India.

    Science.gov (United States)

    Gitte, Sunil Vilasrao; Sabat, Ramanath N; Kamble, K M

    2016-03-01

    To study clinical-epidemiological aspects of children affected with leprosy in a high-endemicity area. Hospital-based study (April 2010 to March 2015) of newly diagnosed children (=18 years) with leprosy, from a leprosy research institute in Chhattisgarh, India. 551 new childhood cases were diagnosed constituting 16% of the total newly leprosy cases examined; 221 (40.1%) were multibacillary cases with 11.2% smear positivity. 243 (44.1%) had known contact history of leprosy, 17.6% of children developed Lepra reaction, and 17.4% had visible deformity. 68% of subjects completed treatment within the prescribed time. Transmission of leprosy is still continuing in the area, and high disability and deformity rates are seen in children.

  9. Single origin and subsequent diversification of central Andean endemic Umbilicaria species.

    Science.gov (United States)

    Hestmark, Geir; Miadlikowska, Jolanta; Kauff, Frank; Fraker, Emily; Molnar, Katalin; Lutzoni, François

    2011-01-01

    We studied an Andean endemic group of species of the lichen-forming fungal genus Umbilicaria from the subalpine and low-alpine zone, with their biogeographic center in Bolivia and Peru. A number of species and varieties have been described from this element, but apparent instability in several morphological traits has made it difficult to precisely delimit taxa. Based on DNA sequences of nuclear ITS, LSU and mitochondrial SSU from extensive collections from Argentina, Bolivia, Chile, Colombia, Ecuador and Peru, we present here a molecular phylogenetic analysis of this Andean endemic element within genus Umbilicaria. All analyses (MP, ML and Bayesian) support a single origin for the element and a division into two major groups characterized by different apothecium types: the Umbilicaria dichroa group and U. calvescens group. Taxa U. krempelhuberi, U. peruviana and U. subcalvescens are nested withinn U. calvescens and are treated as conspecific with the latter species. The endemic element shares a most recent common ancestor with the Umbilicaria vellea group, which has a worldwide distribution and contains several asexually reproducing (sorediate) species. Independent reversals to sexual reproduction might explain the evolution of two types of apothecia in this monophyletic endemic lineage. A number of cosmopolitan, mostly high-alpine, species of Umbilicaria also present in the central Andes are related only remotely to the endemic element and do not exhibit speciation into endemics. Because the An-dean element dominates the Umbilicaria habitats of the low- and subalpine zones we propose that the founder colonized the Andes at a time when the mountains had not yet reached their current elevation while the high-alpine species arrived more recently.

  10. The Stochastic Modelling of Endemic Diseases

    Science.gov (United States)

    Susvitasari, Kurnia; Siswantining, Titin

    2017-01-01

    A study about epidemic has been conducted since a long time ago, but genuine progress was hardly forthcoming until the end of the 19th century (Bailey, 1975). Both deterministic and stochastic models were used to describe these. Then, from 1927 to 1939 Kermack and McKendrick introduced a generality of this model, including some variables to consider such as rate of infection and recovery. The purpose of this project is to investigate the behaviour of the models when we set the basic reproduction number, R0. This quantity is defined as the expected number of contacts made by a typical infective to susceptibles in the population. According to the epidemic threshold theory, when R0 ≤ 1, minor epidemic occurs with probability one in both approaches, but when R0 > 1, the deterministic and stochastic models have different interpretation. In the deterministic approach, major epidemic occurs with probability one when R0 > 1 and predicts that the disease will settle down to an endemic equilibrium. Stochastic models, on the other hand, identify that the minor epidemic can possibly occur. If it does, then the epidemic will die out quickly. Moreover, if we let the population size be large and the major epidemic occurs, then it will take off and then reach the endemic level and move randomly around the deterministic’s equilibrium.

  11. Diversity and endemism of Peruvian mammals

    Directory of Open Access Journals (Sweden)

    Víctor Pacheco

    2011-07-01

    Full Text Available We present an annotated list for all land, aquatic and marine mammals known to occur in Peru and their distribution by ecoregions. We also present species conservation status according to international organizations and the legal conservation status in Peru. At present, we record 508 species, in 13 orders, 50 families, and 218 genera, making Peru the third most diverse country with regards to mammals in the New World, after Brazil and Mexico, and the fifth most diverse country for mammals in the World. This diversity includes 40 didelphimorphs, 2 paucituberculates, 1 manatee, 6 cingulates, 7 pilosa, 39 primates, 162 rodents, 1 rabbit, 2 soricomorphs, 165 bats, 34 carnivores, 2 perissodactyls, and 47 cetartiodactyls. Bats and rodents (327 species represent almost two thirds of total diversity (64% for Peru. Five genera and 65 species (12.8% are endemics to Peru, with the majority of these being rodents (45 species, 69,2%. Most of the endemic species are restricted to the Yungas of the eastern slope of the Andes (39 species, 60% followed by Selva Baja (14 species, 21.5%. The taxonomic status of some species is commented on, when those depart from accepted taxonomy. The marsupial Marmosa phaea; the rodents Melanomys caliginosus, M. robustulus, and Echinoprocta rufescens; the shrew Cryptotis equatoris; the bats Anoura fistulata, Phyllostomus latifolius, Artibeus ravus, Cynomops greenhalli, Eumops maurus, and Rhogeessa velilla; and the carnivore Nasuella olivacea are first records of species occurrence in Peru. Finally, we also include a list of 15 non-native species.

  12. Endemism in the Cladocera (Crustacea: Branchiopoda) of Southern Africa

    OpenAIRE

    2013-01-01

    We review the current state of knowledge and patterns of distribution in the endemic Cladocera (Crustacea: Branchiopoda) of Southern Africa and describe two species of the Western Cape, of which one is new to science. Frey (1993), Korovchinsky (2006) and Smirnov (2008) previously suggested that South Africa harbours few endemics in the Cladocera. In the current study, we show that so-called low endemism in this region is mainly attributed to our limited state of knowledge of the local clado...

  13. Endemic taxa of vascular plants in the Polish Carpathians

    Directory of Open Access Journals (Sweden)

    Halina Piękoś-Mirkowa

    2011-01-01

    Full Text Available The Carpathians, particularly their highest massif, the Tatra Mountains, exhibit the greatest richness of endemics in Poland. The present paper is a critical recapitulation of existing knowledge of endemism among the vascular plants of the Polish part of the Carpathians. It comprises a list of all 110 taxa (49 species, 26 microspecies of the genus Alchemilla and 35 conspicuous subspecies that can be considered Carpathian endemics or subendemics. Their distribution, vertical ranges and habitats are characterized.

  14. Density constraints on the formation of the continental Moho and crust

    Science.gov (United States)

    Herzberg, C. T.; Carr, M. J.; Fyfe, W. S.

    1983-01-01

    As part of a general review of recent high-resolution seismological data, constraints are established for the distribution of mass in the continental crust and upper mantle of the earth. It is shown that the densities of mantle magmas such as MORB-like tholeiites, oicrites, and komatites at 10 kilobars are greater than densities in the continental crust. In order to explain the deviation, a mechanism is proposed for the control of mass transfer during igneous and metamorphic processes throughout geological time. Within the context of a description of the mechanism, the continental crust is characterized as a density filter through which only highly evolved magmas with H2O may pass. It is shown that the removal of less evolved magmas can lead to an over accretion (penetration) or an under accretion (underplating) of magmas in the continental Moho. Some implications of the proposed mechanism for current theoretical models of crust formation are discussed in detail.

  15. Hydroclimatological Controls of Endemic and Non-endemic Cholera of the 20th Century

    Science.gov (United States)

    Jutla, A. S.; Whitcombe, E.; Colwell, R.

    2012-12-01

    Cholera remains a major public health threat for the developing countries. Since the causative agent, Vibrio cholerae, is autochthonous to aquatic environment, it is not possible to eradicate the agent of the disease. Hydroclimatology based prediction and prevention strategies can be implemented in disease susceptible regions for reducing incidence rates. However, the precise role of hydrological and climatological processes, which will further aid in development of suitable prediction models, in creating spatial and temporal environmental conditions favorable for disease outbreak has not been adequately quantified. Here, we show distinction between seasonality and occurrence of cholera in epidemic and non-endemic regions. Using historical cholera mortality data, from the late 1800s for 27 locations in the Indian subcontinent, we show that non-endemic regions are generally located close to regional river systems but away from the coasts and are characterized by single sporadic outbreak in a given year. Increase in air temperature during the low river flow season increases evaporation, leading to an optimal salinity and pH required for bacterial growth. Thereafter, monsoonal rainfall, leads to interactions of contaminated river waters via human activity resulting in cholera epidemics. Endemic regions are located close to coasts where cholera outbreak occurs twice (spring and fall) in a year. Spring outbreak is generally associated with intrusion of bacterial seawater to inland whereas the fall peak is correlated with widespread flooding and cross-contamination of water resources via increased precipitation. This may be one of the first studies to hydroclimatologically quantitatively the seasonality of cholera in both endemic and non-endemic regions. Our results prompt the need of region and cause-specific prediction models for cholera, employing appropriate environmental determinants.

  16. Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre Occidental, Mexico

    NARCIS (Netherlands)

    Lammertink, J.M.; Rojas-Tomé, J.A.; Casillas-Orona, F.M.; Otto, R.L.

    1996-01-01

    The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on

  17. Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre Occidental, Mexico

    NARCIS (Netherlands)

    Lammertink, J.M.; Rojas-Tomé, J.A.; Casillas-Orona, F.M.; Otto, R.L.

    1996-01-01

    The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on a

  18. Estimating the global burden of endemic canine rabies

    National Research Council Canada - National Science Library

    Hampson, Katie; Coudeville, Laurent; Lembo, Tiziana; Sambo, Maganga; Kieffer, Alexia; Attlan, Michaël; Barrat, Jacques; Blanton, Jesse D; Briggs, Deborah J; Cleaveland, Sarah; Costa, Peter; Freuling, Conrad M; Hiby, Elly; Knopf, Lea; Leanes, Fernando; Meslin, François-Xavier; Metlin, Artem; Miranda, Mary Elizabeth; Müller, Thomas; Nel, Louis H; Recuenco, Sergio; Rupprecht, Charles E; Schumacher, Carolin; Taylor, Louise; Vigilato, Marco Antonio Natal; Zinsstag, Jakob; Dushoff, Jonathan

    2015-01-01

    ... of how much this preventable disease costs endemic countries. We established relationships between rabies mortality and rabies prevention and control measures, which we incorporated into a model framework...

  19. Reproductive biology of a highly endemic species: Cipocereus laniflorus N.P. Taylor & Zappi (Cactaceae Biologia reprodutiva de uma espécie altamente endêmica: Cipocereus laniflorus Taylor & Zappi (Cactaceae

    Directory of Open Access Journals (Sweden)

    Juliana Ordones Rego

    2012-03-01

    Full Text Available Cipocereus laniflorus N.P. Taylor & Zappi is an endemic species from the Serra do Caraça, State of Minas Gerais, Brazil. In order to propose conservation strategies for this species, its reproductive strategies were investigated, including reproductive phenology, floral biology, floral visitors and breeding system. The flowering and fruiting period extends from May to October. Few flowers per plant open each night, producing up to 0.4 ml nectar, but 30% of them are nectarless. Probably pollen is also offered as a resource. Fruiting efficiency of C. laniflorus (47% is close to that found in other Cactaceae species. Pollen of this species was detected in Anoura geoffroy, Soricina glossophaga and Pygoderma bilabiatum bats. Amongst the characteristics related to bat-pollination syndrome found in C. laniflorus, the cream-white colouring of the internal part of the flower, the numerous stamens and the nocturnal anthesis of short duration can be highlighted. Flowers of C. laniflorus are also visited by Nitidulidae beetles, Trigona fulviventris bees and hummingbirds, however bats are the main pollinators of this species. Finally, as a self-sterile species, C. laniflorus needs a pollinator and is more susceptible to the risk of extinction if local disturbances affect its pollination system.Cipocereus laniflorus N.P. Taylor & Zappi é uma espécie endêmica da Serra do Caraça, Minas Gerais, Brasil. A fim de se propor estratégias de conservação para esta espécie, estudos sobre sua biologia reprodutiva foram realizados, incluindo fenologia reprodutiva, biologia floral, visitantes florais e o sistema reprodutivo. O período de floração e frutificação ocorre de maio a outubro. Poucas flores abrem-se por planta a cada noite, podendo produzir até 0.4 ml de néctar, poré 30% destas não apresentam néctar. Cipocereus laniflorus provavelmente oferece também pólen como recurso. A eficiência de frutificação sob condições naturais de poliniza

  20. Diversity and bioprospecting of fungal communities associated with endemic and cold-adapted macroalgae in Antarctica.

    Science.gov (United States)

    Godinho, Valéria M; Furbino, Laura E; Santiago, Iara F; Pellizzari, Franciane M; Yokoya, Nair S; Pupo, Diclá; Alves, Tânia M A; Junior, Policarpo A S; Romanha, Alvaro J; Zani, Carlos L; Cantrell, Charles L; Rosa, Carlos A; Rosa, Luiz H

    2013-07-01

    We surveyed the distribution and diversity of fungi associated with eight macroalgae from Antarctica and their capability to produce bioactive compounds. The collections yielded 148 fungal isolates, which were identified using molecular methods as belonging to 21 genera and 50 taxa. The most frequent taxa were Geomyces species (sp.), Penicillium sp. and Metschnikowia australis. Seven fungal isolates associated with the endemic Antarctic macroalgae Monostroma hariotii (Chlorophyte) displayed high internal transcribed spacer sequences similarities with the psychrophilic pathogenic fungus Geomyces destructans. Thirty-three fungal singletons (66%) were identified, representing rare components of the fungal communities. The fungal communities displayed high diversity, richness and dominance indices; however, rarefaction curves indicated that not all of the fungal diversity present was recovered. Penicillium sp. UFMGCB 6034 and Penicillium sp. UFMGCB 6120, recovered from the endemic species Palmaria decipiens (Rhodophyte) and M. hariotii, respectively, yielded extracts with high and selective antifungal and/or trypanocidal activities, in which a preliminary spectral analysis using proton nuclear magnetic resonance spectroscopy indicated the presence of highly functionalised aromatic compounds. These results suggest that the endemic and cold-adapted macroalgae of Antarctica shelter a rich, diversity and complex fungal communities consisting of a few dominant indigenous or mesophilic cold-adapted species, and a large number of rare and/or endemic taxa, which may provide an interesting model of algal-fungal interactions under extreme conditions as well as a potential source of bioactive compounds.

  1. A new species of Uvariopsis (Annonaceae), endemic to the Eastern Arc Mountains of Tanzania

    NARCIS (Netherlands)

    Couvreur, Th.L.P.; Luke, W.R.Q.

    2010-01-01

    The Eastern Arc Mountains of Tanzania enclose high levels of plant and animal diversity with many yet to be described species. Here we describe a new species of the pan-tropical plant family Annonaceae named Uvariopsis lovettiana. It closely resembles another Eastern Arc endemic species, U. bisexual

  2. Case Report: Endemic Amebiasis in Australia: Implications for Residents, Travelers, and Clinicians.

    Science.gov (United States)

    Smith, Simon; Phillips, Gael E; McBride, William J H; Hanson, Josh

    2017-07-01

    Entamoeba histolytica is considered endemic in Australia; however, cases are rare, occurring almost exclusively in high-risk individuals. We describe a series of locally acquired, complicated cases in low-risk individuals from Far North Queensland in whom the diagnosis was delayed. Amebiasis may pose a greater local threat than is currently recognized.

  3. Circulating epstein-barr virus in children living in malaria-endemic areas

    DEFF Research Database (Denmark)

    Rasti, N; Falk, K I; Donati, D;

    2005-01-01

    Children living in malaria-endemic regions have high incidence of Burkitt's lymphoma (BL), the aetiology of which involves Plasmodium falciparum malaria and Epstein-Barr virus (EBV) infections. Acute malarial infection impairs the EBV-specific immune responses with the consequent increase...

  4. Borneo : a quantitative analysis of botanical richness, endemicity and floristic regions based on herbarium records

    NARCIS (Netherlands)

    Raes, Niels

    2009-01-01

    Based on the digitized herbarium records housed at the National Herbarium of the Netherlands I developed high spatial resolution patterns of Borneo's botanical richness, endemicity, and the floristic regions. The patterns are derived from species distribution models which predict a species

  5. Genetic characterization of uniparental lineages in populations from Southwest Iberia with past malaria endemicity

    DEFF Research Database (Denmark)

    Pereira, Vania; Gomes, Verónica; Amorim, António

    2010-01-01

    Malaria endemicity in Southwest Iberia afforded conditions for an increase of sickle cell disease (SCD), which in the region follows a clinal pattern toward the south, where foci of high prevalence were found. SCD distribution is associated with specific geographical areas, and therefore, its...

  6. Tectonics of China: Continental scale cataclastic flow

    Science.gov (United States)

    Gallagher, John J., Jr.

    Stratigraphic, structural, and earthquake evidence indicates that cataclastic flow, that is, flow by brittle mechanisms (e.g., fracture and slip), was dominant in China from late Paleozoic. This process has operated over a range of scales including the continental scale. China is made up of large brittle basement elements immersed in ductile zones which are analogous to porphyroclasts (large, often brittle fragments) surrounded by fluxion (foliation or flow) structures in cataclastic rocks, respectively. This basement fabric for China is seen on Landsat imagery and on tectonic maps and is comparable to cataclastic rock fabrics seen in fault zones, on outcrops, and in thin sections. Brittle basement elements are broken into two or more large rigid blocks, and the dimensions of elements and blocks are within 1 order of magnitude of each other. Ductile zones are made up of fragments which are many orders of magnitude smaller than the ductile zones. Rigid blocks and fragments are identified, and their dimensions are measured through earthquake, fault, and fracture patterns. Rigid basement blocks are surrounded by earthquakes. The sedimentary rocks over the basement faults at the block boundaries seem to be affected by fault movements because they are characterized by facies changes, thickness changes, high-angle faults, and forced folds. Ductile basement zones are earthquake prone, and deformation of the ductile basement affects the overlying sedimentary rocks, as is demonstrated by unconformities and by a wide variety of structures. Thrust faults, buckle folds, and strike slip faults are common in and adjacent to western ductile zones. Structures are most intensely developed where ductile zones abut brittle elements. Both brittle elements and ductile zones are rifted and cut by strike slip faults in eastern China. The mechanical fabric of China and the boundary conditions acting on China are now and always have been determined by its plate tectonic history. This

  7. Styles of continental subduction and collision and their effect on formation and exhumation of UHP rocks

    Science.gov (United States)

    Warren, C. J.; Beaumont, C.; Jamieson, R. A.

    2006-12-01

    Ultra-high pressure (UHP) metamorphic rocks are exposed in many Phanerozoic mountain belts. It is now widely accepted that they represent continental margin rocks that were subducted to ≥100km during the transition from oceanic subduction to continental collision. A range of subduction-collision mechanisms have been proposed to account for UHP formation and exhumation. A series of upper-mantle-scale geodynamic models is used to test the sensitivity of a subset of these mechanisms to variations in lithosphere density, radioactive heat production, and crustal strength. The subducting crust includes an oceanic domain, a continental margin domain with variable width, thickness, strength, and heat production, and a strong internal continental domain. The models involve dynamic subduction, constant convergence velocity, density changes that accompany the main phase changes during burial, and surface erosion in the collision zone. Results show that continental subduction without retro-continent deformation is favored by relatively dense mantle lithosphere. Subduction of the retro-continent (forearc subduction) is associated with shallow-dipping, low- density mantle lithosphere. Back-thrusting of retro-lithosphere is favored by relatively weak retro-continental crust. UHP material can be exhumed in all 3 model styles, depending on the evolving geometry of the subduction-accretion zone and the degree of decoupling between subducting upper and lower continental crust in this zone. Weaker and/or hotter margins decouple and accrete, and their subsequent exhumation is driven by bulk density contrast (buoyancy) and/or forced expulsion in response to advection of strong continental material into the subduction zone (plunger effect). Stronger and/or colder continental margin material is subducted without decoupling and is then transported laterally, underplating the retro-mantle lithosphere. Model results are compatible with observed geometries and PTt paths from some UHP

  8. Antarctic new particle formation from continental biogenic precursors

    Science.gov (United States)

    Kyrö, E.-M.; Kerminen, V.-M.; Virkkula, A.; Dal Maso, M.; Parshintsev, J.; Ruíz-Jimenez, J.; Forsström, L.; Manninen, H. E.; Riekkola, M.-L.; Heinonen, P.; Kulmala, M.

    2013-04-01

    Over Antarctica, aerosol particles originate almost entirely from marine areas, with minor contribution from long-range transported dust or anthropogenic material. The Antarctic continent itself, unlike all other continental areas, has been thought to be practically free of aerosol sources. Here we present evidence of local aerosol production associated with melt-water ponds in continental Antarctica. We show that in air masses passing such ponds, new aerosol particles are efficiently formed and these particles grow up to sizes where they may act as cloud condensation nuclei (CCN). The precursor vapours responsible for aerosol formation and growth originate very likely from highly abundant cyanobacteria Nostoc commune (Vaucher) communities of local ponds. This is the first time freshwater vegetation has been identified as an aerosol precursor source. The influence of the new source on clouds and climate may increase in future Antarctica, and possibly elsewhere undergoing accelerating summer melting of semi-permanent snow cover.

  9. Antarctic new particle formation from continental biogenic precursors

    Directory of Open Access Journals (Sweden)

    E.-M. Kyrö

    2013-04-01

    Full Text Available Over Antarctica, aerosol particles originate almost entirely from marine areas, with minor contribution from long-range transported dust or anthropogenic material. The Antarctic continent itself, unlike all other continental areas, has been thought to be practically free of aerosol sources. Here we present evidence of local aerosol production associated with melt-water ponds in continental Antarctica. We show that in air masses passing such ponds, new aerosol particles are efficiently formed and these particles grow up to sizes where they may act as cloud condensation nuclei (CCN. The precursor vapours responsible for aerosol formation and growth originate very likely from highly abundant cyanobacteria Nostoc commune (Vaucher communities of local ponds. This is the first time freshwater vegetation has been identified as an aerosol precursor source. The influence of the new source on clouds and climate may increase in future Antarctica, and possibly elsewhere undergoing accelerating summer melting of semi-permanent snow cover.

  10. First identification of a chromosomally located penicillinase gene in Kingella kingae species isolated in continental Europe.

    Science.gov (United States)

    Basmaci, Romain; Bidet, Philippe; Berçot, Béatrice; Jost, Christelle; Kwon, Thérésa; Gaumetou, Elodie; Bonacorsi, Stéphane

    2014-10-01

    Kingella kingae is the major pathogen causing osteoarticular infections (OAI) in young children in numerous countries. Plasmid-borne TEM-1 penicillinase production has been sporadically detected in a few countries but not in continental Europe, despite a high prevalence of K. kingae infections. We describe here for the first time a K. kingae β-lactamase-producing strain in continental Europe and demonstrate the novel chromosomal location of the blaTEM-1 gene in K. kingae species.

  11. First Identification of a Chromosomally Located Penicillinase Gene in Kingella kingae Species Isolated in Continental Europe

    OpenAIRE

    Basmaci, Romain; Bidet, Philippe; Berçot, Béatrice; Jost, Christelle; Kwon, Thérésa; Gaumetou, Elodie; Bonacorsi, Stéphane

    2014-01-01

    Kingella kingae is the major pathogen causing osteoarticular infections (OAI) in young children in numerous countries. Plasmid-borne TEM-1 penicillinase production has been sporadically detected in a few countries but not in continental Europe, despite a high prevalence of K. kingae infections. We describe here for the first time a K. kingae β-lactamase-producing strain in continental Europe and demonstrate the novel chromosomal location of the blaTEM-1 gene in K. kingae species.

  12. The Agulhas-Karoo Geoscience Transect: Structures and processes along the southern African continental margin

    OpenAIRE

    N. Parsiegla; Gohl, K.; Uenzelmann-Neben, G.; Jacek Stankiewicz

    2008-01-01

    The southern African continental transform margin is of great interest for the understanding of processes related to continental breakup, transform fault formation and vertical plate motion. Open questions include the cause and consequences for the high topography of southern Africa, neotectonic activity along the Agulhas-Falkland Fracture Zone and the formation of the Outeniqua Basin. As a component of the project “Inkaby yeAfrica”, the 900 km long Agulhas-Karoo Geoscience Transect was carri...

  13. Density Sorting During the Evolution of Continental Crust

    Science.gov (United States)

    Kelemen, P. B.; Behn, M. D.; Hacker, B. R.

    2015-12-01

    We consider two settings - in addition to "delamination" of arc lower crust - in which dense, mafic eclogites founder into the convecting mantle while buoyant, felsic lithologies accumulate at the base of evolving continental crust. Arc processes play a central role in generating continental crust, but it remains uncertain how basaltic arc crust is transformed to andesitic continental crust. Dense, SiO2-poor products of fractionation may founder from the base of arc crust by "delamination", but lower arc crust after delamination has significantly different trace elements compared to lower continental crust (LCC). In an alternative model, buoyant magmatic rocks generated at arcs are first subducted, mainly via subduction erosion. Upon heating, these buoyant lithologies ascend through the mantle wedge or along a subduction channel, and are "relaminated" at
the base of overlying crust (e.g., Hacker et al EPSL 11, AREPS 15). Average buoyant lavas and plutons
for the Aleutians, Izu-Bonin-Marianas, Kohistan and Talkeetna arcs fall within the range of estimated LCC major and trace elements. Relamination is more efficient in generating continental crust than delamination. Himalayan cross-sections show Indian crust thrust beneath Tibetan crust, with no intervening mantle. There is a horizontal Moho at ca 80 km depth, extending from thickened Indian crust, across the region where Tibetan crust overlies Indian crust, into thickened Tibetan crust. About half the subducted Indian crust is present, whereas the other half is missing. Data (Vp/Vs; Miocene lavas formed by interaction of continental crust with mantle; xenolith thermometry) indicate 1000°C or more from ca 50 km depth to the Moho since the Miocene. We build on earlier studies (LePichon et al Tectonics 92, T'phys 97; Schulte-Pelkum et al Nature 05; Monsalve et al JGR 08) to advance the hypothesis that rapid growth of garnet occurs at 70-80 km and 1000°C within subducting Indian crust. Dense eclogites founder

  14. Geological features and geophysical signatures of continental margins of India

    Digital Repository Service at National Institute of Oceanography (India)

    Krishna, K.S.

    and classification of continental margins are in general dependent on style of continental splitting, rifting, subsidence and their proximity to the tectonic plate boundaries, at times the margins undergo for modifications by sediment deposition and volcanic... by Deccan-Reunion hotspot volcanism and Bengal Fan sedimentation respectively. Volcanism has dominated on the western continental margin of India, thereby the margin had been turned into a volcanic passive continental margin, while eastern continental...

  15. China's endemic vertebrates sheltering under the protective umbrella of the giant panda.

    Science.gov (United States)

    Li, Binbin V; Pimm, Stuart L

    2016-04-01

    The giant panda attracts disproportionate conservation resources. How well does this emphasis protect other endemic species? Detailed data on geographical ranges are not available for plants or invertebrates, so we restrict our analyses to 3 vertebrate taxa: birds, mammals, and amphibians. There are gaps in their protection, and we recommend practical actions to fill them. We identified patterns of species richness, then identified which species are endemic to China, and then which, like the panda, live in forests. After refining each species' range by its known elevational range and remaining forest habitats as determined from remote sensing, we identified the top 5% richest areas as the centers of endemism. Southern mountains, especially the eastern Hengduan Mountains, were centers for all 3 taxa. Over 96% of the panda habitat overlapped the endemic centers. Thus, investing in almost any panda habitat will benefit many other endemics. Existing panda national nature reserves cover all but one of the endemic species that overlap with the panda's distribution. Of particular interest are 14 mammal, 20 bird, and 82 amphibian species that are inadequately protected. Most of these species the International Union for Conservation of Nature currently deems threatened. But 7 mammal, 3 bird, and 20 amphibian species are currently nonthreatened, yet their geographical ranges are <20,000 km(2) after accounting for elevational restriction and remaining habitats. These species concentrate mainly in Sichuan, Yunnan, Nan Mountains, and Hainan. There is a high concentration in the east Daxiang and Xiaoxiang Mountains of Sichuan, where pandas are absent and where there are no national nature reserves. The others concentrate in Yunnan, Nan Mountains, and Hainan. Here, 10 prefectures might establish new protected areas or upgrade local nature reserves to national status. © 2015 Society for Conservation Biology.

  16. Amphibian diversity and endemism in the swamp forests of Agusan Marsh, Agusan del Sur, Philippines

    Directory of Open Access Journals (Sweden)

    Merlita L. Almeria

    2013-04-01

    Full Text Available Agusan Marsh, an ecologically significant wetland in the Philippines, consists of an extensivefloodplain heavily dissected by numerous rivers and streams making it a very important source offreshwater, storing more than 15% of the nation’s freshwater resource in the form of swamp forests.Since amphibians are very good indicators of climate change and ecosystem health, species diversity andendemism were assessed in sago swamp, terminalia, mixed swamp, and peat swamp forests in AgusanMarsh using a combination of cruising, pitfall trap and quadrat methods. Seventeen species with 41%endemism were recorded. Of the seven endemic species, five are Mindanao endemic. The twoundescribed species of Oreophryne and one Philautus could be new species and were observed in theterminalia, sago, and mixed swamp forests but not in the peat swamp forest. The peat swamp forestwhere the invasive Rhinella marina was abundant, had the least species richness owing to habitatdisturbance brought about by human encroachment. The highest species richness and abundance wereobserved in the terminalia forest primarily due to the presence of suitable microhabitats. Four vulnerablespecies were recorded in the marsh. Most of the vulnerable and endemic species were documented in theterminalia and mixed swamp forests. High diversity and more or less even distribution were observed inall sites. Three amphibian species are considered socio-economically important and are hunted for foodand bait for fish. The presence of endemic and vulnerable species indicates that Agusan Marsh is a keyconservation site. Logging and widespread mining, discharging tons of mine tailings into the rivers whichfind their way into the swamp forests are just some of the threats to the amphibians in the marsh.Conservation action is necessary to protect the endemic and vulnerable species in the swamp forests andthe Agusan marsh in general.

  17. Evaluating Hypotheses of Plant Species Invasions on Mediterranean Islands: Inverse Patterns between Alien and Endemic Species

    Directory of Open Access Journals (Sweden)

    Alexander Bjarnason

    2017-08-01

    Full Text Available Invasive alien species cause major changes to ecosystem functioning and patterns of biodiversity, and the main factors involved in invasion success remain contested. Using the Mediterranean island of Crete, Greece as a case study, we suggest a framework for analyzing spatial data of alien species distributions, based on environmental predictors, aiming to gain an understanding of their spatial patterns and spread. Mediterranean islands are under strong ecological pressure from invading species due to their restricted size and increased human impact. Four hypotheses of invasibility, the “propagule pressure hypothesis” (H1, “biotic resistance hypothesis vs. acceptance hypothesis” (H2, “disturbance-mediated hypothesis” (H3, and “environmental heterogeneity hypothesis” (H4 were tested. Using data from alien, native, and endemic vascular plant species, the propagule pressure, biotic resistance vs. acceptance, disturbance-mediated, and environmental heterogeneity hypotheses were tested with Generalized Additive Modeling (GAM of 39 models. Based on model selection, the optimal model includes the positive covariates of native species richness, the negative covariates of endemic species richness, and land area. Variance partitioning between the four hypotheses indicated that the biotic resistance vs. acceptance hypothesis explained the vast majority of the total variance. These results show that areas of high species richness have greater invasibility and support the acceptance hypothesis and “rich-get-richer” distribution of alien species. The negative correlation between alien and endemic species appears to be predominantly driven by altitude, with fewer alien and more endemic species at greater altitudes, and habitat richness. The negative relationship between alien and endemic species richness provides potential for understanding patterns of endemic and alien species on islands, contributing to more effective conservation

  18. Origin and differentiation of endemism in the flora of China

    Institute of Scientific and Technical Information of China (English)

    WU Zhengyi; SUN Hang; ZHOU Zhekun; PENG Hua; LI Dezhu

    2007-01-01

    The present paper analyzed 239 endemic genera in 67 families in the flora of seed plants in China.The results showed that there are five families containing more than ten endemic genera,namely,Gesneriaceae (27),which hereafter refers to the number of endemic genera in China,Composite (20),Labiatae (12),Cruciferae (11),and Umbelliferae (10),15 families with two endemic genera,and another 30 families with only one endemic genus.Four monotypic families (Ginkgoaceae,Davidiaceae,Eucommiaceae and Acanthochlamydaceae)are the most ancient,relict and characteristic in the flora of seed plants in China.Based on integrative data of systematics,fossil history,and morphological and molecular evidence of these genera,their origin,evolution and relationships were discussed.In gymnosperms,all endemic genera are relicts of the Arctic-Tertiary flora,having earlier evolutionary history,and can be traced back to the Cretaceous or to the Jurassic and even earlier.In angiosperms,the endemic genera are mostly relicts,and are represented in all lineages in the"Eight-Class System ofClassification of Angiosperms",and endemism can be found in almost every evolutionary stage of extant angiosperms.The relict genera once occupied huge areas in the northern hemisphere in the Tertiary or the late Cretaceous,while neo-endemism mostly originated in the late Tertiary.They came from Arctic-Tertiary,Paleo-tropical-Tertiary and Tethys-Tertiary florisitic elements,and the blend of the three elements with many genera of autochthonous origin.The endemism was formed when some dispersal routes such as the North Atlantic Land Bridge,and the Bering Bridge became discontinuous during the Tertiary,as well as the climate change and glaciations in the late Tertiary and the Quaternary.Therefore,the late Tertiary is the starting point of extant endemism of the flora in China.

  19. Diversity, rarity and the evolution and conservation of the Canary Islands endemic flora

    Directory of Open Access Journals (Sweden)

    Reyes-Betancort, J. Alfredo

    2008-06-01

    Full Text Available The endemic vascular flora of the Canary Islands comprises over 680, taxa collectively accounting for more than 50% of the total native flora. To investigate geographical patterns of diversity within the endemic flora, distribution data from published sources together with other field observation and herbarium data were used to compile a data matrix comprising the distributions of ca. 90% of endemic taxa scored on a 10 × 10km UTM grid. WORLDMAP was then used to investigate patterns of endemic diversity, range size rarity (a measure of endemicity, phylogenetic diversity and threatened taxon richness. Endemic taxon richness was found to be highly heterogeneous across the archipelago, with cells containing between one and 139 taxa each (0.05-22.82% of endemic diversity. Patterns of variation in range size rarity and phylogenetic diversity were found to be largely congruent with endemic diversity, although some cells exhibited markedly higher range size rarity scores than would be predicted by their endemic diversity scores. In contrast, the pattern of endangered taxon richness across the archipelago differed markedly from endemic taxon richness. Many cells in Lanzarote, Fuerteventura and Gran Canaria exhibit higher endangered taxon richness scores than would be predicted from their endemic richness scores whereas in Tenerife, El Hierro, La Palma and La Gomera, the converse is generally true. The implications of the results both for understanding the evolution of Canary Island endemic diversity and for the conservation of the region’s unique and vulnerable flora are considered.La flora vascular endémica de las Islas Canarias comprende unos 680 táxones, lo que viene a representar más del 50% de la flora nativa. Con objeto de investigar patrones geográficos de diversidad en la flora endémica, se recopilaron los datos publicados que, junto con otras observaciones de campo y datos de herbario, sirvieron para completar una matriz de datos

  20. Sufficient conditions of endemic threshold on metapopulation networks

    CERN Document Server

    Takaguchi, Taro

    2014-01-01

    In the present paper, we focus on susceptible-infected-susceptible dynamics on metapopulation networks in which nodes represent subpopulations. Recent studies suggest that heterogeneous network structure between elements plays an important role in determining the threshold of infection rate at the onset of epidemics, one of fundamental quantities governing epidemic dynamics. We consider the general case in which the infection rate at each node depends on its population size, as shown in recent empirical observations. We prove that the sufficient condition for the endemic threshold (i.e., its upper bound), which was previously derived based on a mean-field approximation of network structure, also holds true for arbitrary networks. We also derive an improved condition which implies that networks with the rich-club property (that is, high connectivity between nodes with large number of links) are more favorable to disease spreading. The dependency of infection rate on population size introduces remarkable differ...

  1. Endemic human fasciolosis in the Bolivian Altiplano.

    Science.gov (United States)

    Parkinson, M; O'Neill, S M; Dalton, J P

    2007-05-01

    Fasciolosis, caused by trematodes of the genus Fasciola, is an emerging disease of humans. One of the highest levels of human fasciolosis hepatica is found amongst the indigenous Aymaran people of the Northern Bolivian Altiplano. A meta-analysis of epidemiological surveys from 38 communities in the region demonstrates that fasciolosis has been endemic in the region since at least 1984 and is a zoonosis of rural communities. Human and bovine fasciolosis is associated with the communities lying in the plain from Lake Titicaca to La Paz, predominantly in the Los Andes province. In Los Andes incidences of up to 67% of population cohorts were found, and prevalence is age-related with the highest infection rate in children aged 8-11 years.

  2. [The endemic goitre in figurative arts].

    Science.gov (United States)

    Giampalmo, A

    1996-01-01

    For the past fifteen years the author has been collecting photografic documentation of works of figurative arts (graffiti, mosiac, engravings, paintings and sculptures) made at different times and places, in which he found mostly unintentional display of diseases or deformities that would be clearly identified in nosography in the light of today's knowledge. In this study the author intends to illustrate briefly different cases on endemic goitre - whose representation is particularly frequent in figurative arts - in chronological order, beginning with the most ancient ones and focussing on Italian portraying of the Nativity and the Passion of Christ, where the most striking infirmities and disabilities were mirrored and commonly accepted. This study whose interest lies between a scientific and a humanistic one has also importance in the field of art, and especially in relevant philological research which is of particular importance to us pathologists. At last it contribute to establish the epidemiology of some diseases and the knowledge of historical and geographical pathology.

  3. Cytotoxic compounds from endemic Arnebia purpurea.

    Science.gov (United States)

    Yuzbasioglu, Merve; Kuruuzum-Uz, Ayse; Guvenalp, Zuhal; Simon, András; Tóth, Gabór; Harput, U Sebnem; Kazaz, Cavit; Bilgili, Bilgehan; Duman, Hayri; Saracoglu, Iclal; Demirezer, L Omur

    2015-04-01

    Phytochemical studies of the roots and aerial parts of endemic Arnebia purpurea S. Erik & H. Sumbul resulted in the isolation and characterization of four naphthoquinones [isovalerylalkannin (1), α-methyl-n-butanoyl alkannin (2), acetylalkannin (3), and alkannin (4)], a triterpene derivative [3-O-acetyl-oleanolic acid (5)], a steroid [β-sitosterol (6)], three flavonoid glycosides [isorhamnetin-3-O-rutinoside (7), kaempferol-3-O-rutinoside (8), kaempferol 3-O-(5"-acetyl) apiofuranoside 7-O-rhamnopyranoside (9)] and a phenolic acid [rosmarinic acid (10)]. 3-O-Acetyl-oleanolic acid, isorhamnetin-3-O-rutinoside, kaempferol-3-O-mrutinoside, and kaempferol 3-O-(5"-acetyl) apiofuranoside 7-O-rhamnopyranoside are reported from an Arnebia species for the first time. Cytotoxic activities on L929 murine fibrosarcoma cell line of the isolated compounds were investigated using MTT assay. Naphthoquinones (1-4) showed intermediate cytotoxic activity in comparison with the standard, doxorubicin.

  4. On the freshening of the northwestern Weddell Sea continental shelf

    Directory of Open Access Journals (Sweden)

    H. H. Hellmer

    2011-05-01

    Full Text Available We analyzed hydrographic data from the northwestern Weddell Sea continental shelf of the three austral winters 1989, 1997, and 2006 and two summers following the last winter cruise. During summer a thermal front exists at ~64° S separating cold southern waters from warm northern waters that have similar characteristics as the deep waters of the central basin of the Bransfield Strait. In winter, the whole continental shelf exhibits southern characteristics with high Neon (Ne concentrations, indicating a significant input of glacial melt water. The comparison of the winter data from the shallow shelf off the tip of the Antarctic Peninsula, spanning a period of 17 yr, shows a salinity decrease of 0.09 for the whole water column, which has a residence time of <1 yr. We interpret this freshening as being caused by a combination of reduced salt input due to a southward sea ice retreat and higher precipitation during the late 20th century on the western Weddell Sea continental shelf. However, less salinification might also result from a delicate interplay between enhanced salt input due to sea ice formation in coastal areas formerly occupied by Larsen A and B ice shelves and increased Larsen C ice loss.

  5. On the freshening of the northwestern Weddell Sea continental shelf

    Directory of Open Access Journals (Sweden)

    H. H. Hellmer

    2010-12-01

    Full Text Available We analysed hydrographic data from the northwestern Weddell Sea continental shelf of three austral winters (1989, 1997 and 2006 and two summers following the last winter cruise. During summer a thermal front exists at ~64° S separating cold southern waters from warm northern waters that have similar characteristics as the deep waters of the central basin of the Bransfield Strait. In winter, the whole continental shelf exhibits southern characteristics with high Neon (Ne concentrations, indicating a significant input of glacial melt water. The comparison of the winter data at the tip of the Antarctic Peninsula, spanning a period of 17 years, shows a salinity decrease of 0.09 for the whole water column. We interpret this freshening as a reduction in salt input to the water masses being advected northward on the western Weddell Sea continental shelf. Possible causes for the reduced winter salinification are a southward retreat of the summer sea ice edge together with more precipitation in this sector. However, the latter might have happened in conjunction with an increase in ice shelf mass loss, counteracting an enhanced salt input due to sea ice formation in coastal areas formerly occupied by Larsen A and B ice shelves.

  6. On the origin of endemic species in the Red Sea

    KAUST Repository

    DiBattista, Joseph

    2015-10-19

    Aim The geological and palaeo-climatic forces that produced the unique biodiversity in the Red Sea are a subject of vigorous debate. Here, we review evidence for and against the hypotheses that: (1) Red Sea fauna was extirpated during glacial cycles of the Pleistocene and (2) coral reef fauna found refuge within or just outside the Red Sea during low sea level stands when conditions were inhospitable. Location Red Sea and Western Indian Ocean. Methods We review the literature on palaeontological, geological, biological and genetic evidence that allow us to explore competing hypotheses on the origins and maintenance of shallow-water reef fauna in the Red Sea. Results Palaeontological (microfossil) evidence indicates that some areas of the central Red Sea were devoid of most plankton during low sea level stands due to hypersaline conditions caused by almost complete isolation from the Indian Ocean. However, two areas may have retained conditions adequate for survival: the Gulf of Aqaba and the southern Red Sea. In addition to isolation within the Red Sea, which separated the northern and southern faunas, a strong barrier may also operate in the region: the cold, nutrient-rich water upwelling at the boundary of the Gulf of Aden and the Arabian Sea. Biological data are either inconclusive or support these putative barriers and refugia, but no data set, that we know of rejects them. Genetic evidence suggests that many endemic lineages diverged from their Indian Ocean counterparts long before the most recent glaciations and/or are restricted to narrow areas, especially in the northern Red Sea. Main conclusions High endemism observed in the Red Sea and Gulf of Aden appears to have multiple origins. A cold, nutrient-rich water barrier separates the Gulf of Aden from the rest of the Arabian Sea, whereas a narrow strait separates the Red Sea from the Gulf of Aden, each providing potential isolating barriers. Additional barriers may arise from environmental gradients

  7. Evidence for endemic chikungunya virus infections in Bandung, Indonesia

    NARCIS (Netherlands)

    Kosasih, H.; Mast, Q. de; Widjaja, S.; Sudjana, P.; Antonjaya, U.; Ma'roef, C.; Riswari, S.F.; Porter, K.R.; Burgess, T.H.; Alisjahbana, B.; Ven, A. van der; Williams, M.

    2013-01-01

    Chikungunya virus (CHIKV) is known to cause sporadic or explosive outbreaks. However, little is known about the endemic transmission of CHIKV. To ascertain the endemic occurrence of CHIKV transmission, we tested blood samples from patients with a non-dengue febrile illness who participated in a pros

  8. The geomorphology of a glaciated continental shelf, Western Scotland, UK

    Science.gov (United States)

    Howe, John; Dove, Dayton; Bradwell, Tom

    2013-04-01

    We present recently collected swath bathymetry and legacy seismic data from two regions of the north-west UK continental shelf: the Sea of the Hebrides; and the Firth of Lorn, western Scotland. Both regions have experienced extensive Pleistocene ice sheet glaciation and both provide abundant geomorphological evidence of subglacial and postglacial processes. The Sea of the Hebrides bathymetry data cover 2200 km2 and provide new geomorphological evidence for an ice stream flowing from western Scotland and the Inner Hebrides focusing towards a trough-mouth fan (the Barra Fan) at the continental shelf break during the height of the last glaciation. Notably, bedrock structures provide a control on the location and orientation of glacially overdeepened basins and troughs on the inner shelf. Whilst around the Islands of Canna and Rum, convergent seabed glacial lineations and other subglacially streamlined features eroded in bedrock preserve the direction of ice sheet movement - indicating ice streaming in a south-westerly direction across the continental shelf. We propose that this fast-flow zone formed part of a larger convergent ice stream system draining much of western Scotland and the north of Ireland. The Firth of Lorn bathymetry acquisition comprises 553km2 of data, collected as part of the INIS Hydro program (Ireland, Northern Ireland and Scotland Hydrographic Survey). This region of nearshore continental shelf is revealed as predominantly bedrock-dominated seabed, characterised by a series of narrow, strongly fault-controlled troughs, part of the Great Glen Fault Zone complex. Evidence for glaciation is widespread and well preserved in the Firth of Lorn and surrounding seabed with moraines, bedrock lineations (?megagrooves?) and overdeepened basins common across the area. Initial mapping shows that our understanding of the configuration and style of deglaciation in these sectors of the former British-Irish Ice Sheet can be greatly improved by the collection of

  9. MULTI-ARC BASIN SYSTEM OF THE KUNLUN OROGENIC BELT AND PAN-CATHYSIAN CONTINENTAL ACCRETION

    Institute of Scientific and Technical Information of China (English)

    YIN Fuguang; PAN Guitang; LI Xingzhen

    2003-01-01

    After Rodinia supercontinent was disintegrated in Late Proterozoic, an ocean, namely, Tethys Ocean, occurred between Gondwana continental group and Pan-Cathaysian continental group from Late Proterozoic to Mesozoic. From Early Paleozoic to Mesozoic, Tethys Ocean was subducted toward Pan-Cathaysian block group, which results in backarc expansion, arc-land collision and forearc accretion. When the backarc basin expands and reaches the small oceanic basin, ophiolite melange will be generated. As accretion had already occurred in the south of the continental margin in the earlier stage, the succeeding backarc expansion and the frontal arc position were migrated toward south correspondingly. Therefore, multiple ophiolite belts and magmatic rock belts occurred, and show a trend of decreasing age from north toward south. As the continental margin was split and migrated toward south and reached a high latitude position, i.e., with the shortening and subduction of oceanic crust, the sedimentary bodies at high latitude was accreted continuously toward low latitude area together with the formation of oceanic island, mixing of cold-type and warm-type organism was generated. Moreover,blocks split and separated from Pan-Cathaysian or Gondwana continental group cannot traverse the oceanic median ridge and joins with another continental block. As a result, the Kunlun belt on the SW margin of the Pan-Cathaysian land was resulted from the multi-arc orogenesis such as the backarc seabed expansion, arc-arc collision, arc-land collision oceanic bed, and the continuous southward accretion process.

  10. [Endemic goiter in Nepal. Comparisons with endemic goiter in the Piedmont].

    Science.gov (United States)

    Mortara, M; Cenderelli, G; Reposi, G; Migiardi, M; Costa, A

    1976-11-10

    Comparison of certain features of endemic goitre in the Khumbu district of Nepal and Piedmont is reported. Cases in the younger generations were observed in both areas. In Khumbu, the incidence of goitre in schoolchildren was 75% and cases were even noted in children who had been receiving iodine prophylactic management (injections of iodised oil: 500-1000 mg/yr) for at least three years. The iodine content of drinking water and the most commonly eaten foods was determined. Values were very low and a daily intake of not more than 30 mug was calculated. The findings are in line with metabolic studies carried out by other workers in Upper Khumbu. While it is clear that ambiental iodine deficiency is much higher in Khumbu than in those areas of Piedmont where goitre is most markedly endemic, the inadequacy of preventive iodine administration measures, and environmental features common to both areas, suggest that iodine deficiency is a concomitant factor and not the prime cause of endemic goitre.

  11. Modeling Extinction Risk of Endemic Birds of Mainland China

    Directory of Open Access Journals (Sweden)

    Youhua Chen

    2013-01-01

    Full Text Available The extinction risk of endemic birds of mainland China was modeled over evolutionary time. Results showed that extinction risk of endemic birds in mainland China always tended to be similar within subclades over the evolutionary time of species divergence, and the overall evolution of extinction risk of species presented a conservatism pattern, as evidenced by the disparity-through-time plot. A constant-rate evolutionary model was the best one to quantify the evolution of extinction risk of endemic birds of mainland China. Thus, there was no rate shifting pattern for the evolution of extinction risk of Chinese endemic birds over time. In a summary, extinction risk of endemic birds of mainland China is systematically quantified under the evolutionary framework in the present work.

  12. Global warming and extinctions of endemic species from biodiversity hotspots.

    Science.gov (United States)

    Malcolm, Jay R; Liu, Canran; Neilson, Ronald P; Hansen, Lara; Hannah, Lee

    2006-04-01

    Global warming is a key threat to biodiversity, but few researchers have assessed the magnitude of this threat at the global scale. We used major vegetation types (biomes) as proxies for natural habitats and, based on projected future biome distributions under doubled-CO2 climates, calculated changes in habitat areas and associated extinctions of endemic plant and vertebrate species in biodiversity hotspots. Because of numerous uncertainties in this approach, we undertook a sensitivity analysis of multiple factors that included (1) two global vegetation models, (2) different numbers of biome classes in our biome classification schemes, (3) different assumptions about whether species distributions were biome specific or not, and (4) different migration capabilities. Extinctions were calculated using both species-area and endemic-area relationships. In addition, average required migration rates were calculated for each hotspot assuming a doubled-CO2 climate in 100 years. Projected percent extinctions ranged from global vegetation model and then by migration and biome classification assumptions. Bootstrap comparisons indicated that effects on hotpots as a group were not significantly different from effects on random same-biome collections of grid cells with respect to biome change or migration rates; in some scenarios, however, botspots exhibited relatively high biome change and low migration rates. Especially vulnerable hotspots were the Cape Floristic Region, Caribbean, Indo-Burma, Mediterranean Basin, Southwest Australia, and Tropical Andes, where plant extinctions per hotspot sometimes exceeded 2000 species. Under the assumption that projected habitat changes were attained in 100 years, estimated global-warming-induced rates of species extinctions in tropical hotspots in some cases exceeded those due to deforestation, supporting suggestions that global warming is one of the most serious threats to the planet's biodiversity.

  13. Kenyan endemic bird species at home in novel ecosystem.

    Science.gov (United States)

    Habel, Jan Christian; Teucher, Mike; Rödder, Dennis; Bleicher, Marie-Therese; Dieckow, Claudia; Wiese, Anja; Fischer, Christina

    2016-04-01

    Riparian thickets of East Africa harbor a large number of endemic animal and plant species, but also provide important ecosystem services for the human being settling along streams. This creates a conflicting situation between nature conservation and land-use activities. Today, most of this former pristine vegetation is highly degraded and became replaced by the invasive exotic Lantana camara shrub species. In this study, we analyze the movement behavior and habitat use of a diverse range of riparian bird species and model the habitat availability of each of these species. We selected the following four riparian bird species: Bare-eyed Thrush Turdus tephronotus, Rufous Chatterer Turdoides rubiginosus, Zanzibar Sombre Greenbul Andropadus importunus insularis, and the Kenyan endemic Hinde's Babbler Turdoides hindei. We collected telemetric data of 14 individuals during a 2 months radio-tracking campaign along the Nzeeu River in southeast Kenya. We found that (1) all four species had similar home-range sizes, all geographically restricted and nearby the river; (2) all species mainly use dense thicket, in particular the invasive L. camara; (3) human settlements were avoided by the bird individuals observed; (4) the birds' movement, indicating foraging behavior, was comparatively slow within thickets, but significantly faster over open, agricultural areas; and (5) habitat suitability models underline the relevance of L. camara as suitable surrogate habitat for all understoreyed bird species, but also show that the clearance of thickets has led to a vanishing of large and interconnected thickets and thus might have negative effects on the population viability in the long run.

  14. French Extended Continental Shelf Mapping: example of new continental margin understanding offshore French Guiana

    Science.gov (United States)

    Roest, Walter; Loubrieu, Benoit; Loncke, Lies; Basile, Christophe; Graindorge, David; Shipboard Party, Guyaplac

    2017-04-01

    Under the United Nations Convention on the Law of the Sea, Coastal States can extend sovereign rights over the natural resources of the Continental Shelf beyond 200 nautical miles (M) if they can demonstrate that their continental margin extends beyond this distance from the coast. Article 76 of the Convention defines the continental shelf and includes geomorphological and geological criteria to claim such a shelf beyond 200 M. Since 2006, France has filed 7 submissions for a total of 10 distinct geographic regions to the Commission on the Limits of the Continental Shelf that was established by the Convention to examine those claims, and make recommendations with respect to the justification of the outer limits of the continental shelf. To support the French submissions, a significant effort was employed in acquiring new marine geophysical and geological data and compiling existing data along the deep water parts of the continental margins offshore all the French overseas territories. In this presentation, we will discuss the example of French Guiana, where the data collected for the purpose of fulfilling the obligation under the Convention to submit data and information to the Commission within a 10 year time frame have led to new understanding of the transform continental margin and the Demerara Plateau located to the north of French Guiana and Surinam. In addition, the data collected for this purpose have led to new scientific questions and have encouraged new and enhanced scientific collaboration between French government organizations and the academic community. Follow up research and scientific cruises that will be presented in separate communications have addressed sedimentary processes including contourites, giant comet tail like depressions probably associated with the strong bottom currents observed along the continental slope and potentially related to pockmarks, as well as giant submarine landslides. Most recently, multichannel reflection and wide angle

  15. Syphilis and the endemic treponematoses : clinical, (histo-) pathological and laboratory studies

    NARCIS (Netherlands)

    H.J.H. Engelkens (Herman)

    1993-01-01

    textabstractTreponemal diseases important to mankind are sexually transmitted syphilis and the endemic nonvenereally transmitted treponematoses (yaws, pinta, and endemic syphilis). Historically, the most important disease caused by treponemes is syphilis. During the last few decades, yaws, endemic s

  16. Population genetic structure of Plasmodium falciparum across a region of diverse endemicity in West Africa

    Directory of Open Access Journals (Sweden)

    Mobegi Victor A

    2012-07-01

    Full Text Available Abstract Background Malaria parasite population genetic structure varies among areas of differing endemicity, but this has not been systematically studied across Plasmodium falciparum populations in Africa where most infections occur. Methods Ten polymorphic P. falciparum microsatellite loci were genotyped in 268 infections from eight locations in four West African countries (Republic of Guinea, Guinea Bissau, The Gambia and Senegal, spanning a highly endemic forested region in the south to a low endemic Sahelian region in the north. Analysis was performed on proportions of mixed genotype infections, genotypic diversity among isolates, multilocus standardized index of association, and inter-population differentiation. Results Each location had similar levels of pairwise genotypic diversity among isolates, although there were many more mixed parasite genotype infections in the south. Apart from a few isolates that were virtually identical, the multilocus index of association was not significant in any population. Genetic differentiation between populations was low (most pairwise FST values  Conclusions Although proportions of mixed genotype infections varied with endemicity as expected, population genetic structure was similar across the diverse sites. Very substantial reduction in transmission would be needed to cause fragmented or epidemic sub-structure in this region.

  17. Recombination drives genetic diversification of Streptococcus dysgalactiae subspecies equisimilis in a region of streptococcal endemicity.

    Science.gov (United States)

    McMillan, David J; Kaul, Santosh Y; Bramhachari, P V; Smeesters, Pierre R; Vu, Therese; Karmarkar, M G; Shaila, Melkote S; Sriprakash, Kadaba S

    2011-01-01

    Infection of the skin or throat by Streptococcus dysgalactiae subspecies equisimilis (SDSE) may result in a number of human diseases. To understand mechanisms that give rise to new genetic variants in this species, we used multi-locus sequence typing (MLST) to characterise relationships in the SDSE population from India, a country where streptococcal disease is endemic. The study revealed Indian SDSE isolates have sequence types (STs) predominantly different to those reported from other regions of the world. Emm-ST combinations in India are also largely unique. Split decomposition analysis, the presence of emm-types in unrelated clonal complexes, and analysis of phylogenetic trees based on concatenated sequences all reveal an extensive history of recombination within the population. The ratio of recombination to mutation (r/m) events (11:1) and per site r/m ratio (41:1) in this population is twice as high as reported for SDSE from non-endemic regions. Recombination involving the emm-gene is also more frequent than recombination involving housekeeping genes, consistent with diversification of M proteins offering selective advantages to the pathogen. Our data demonstrate that genetic recombination in endemic regions is more frequent than non-endemic regions, and gives rise to novel local SDSE variants, some of which may have increased fitness or pathogenic potential.

  18. Recombination drives genetic diversification of Streptococcus dysgalactiae subspecies equisimilis in a region of streptococcal endemicity.

    Directory of Open Access Journals (Sweden)

    David J McMillan

    Full Text Available Infection of the skin or throat by Streptococcus dysgalactiae subspecies equisimilis (SDSE may result in a number of human diseases. To understand mechanisms that give rise to new genetic variants in this species, we used multi-locus sequence typing (MLST to characterise relationships in the SDSE population from India, a country where streptococcal disease is endemic. The study revealed Indian SDSE isolates have sequence types (STs predominantly different to those reported from other regions of the world. Emm-ST combinations in India are also largely unique. Split decomposition analysis, the presence of emm-types in unrelated clonal complexes, and analysis of phylogenetic trees based on concatenated sequences all reveal an extensive history of recombination within the population. The ratio of recombination to mutation (r/m events (11:1 and per site r/m ratio (41:1 in this population is twice as high as reported for SDSE from non-endemic regions. Recombination involving the emm-gene is also more frequent than recombination involving housekeeping genes, consistent with diversification of M proteins offering selective advantages to the pathogen. Our data demonstrate that genetic recombination in endemic regions is more frequent than non-endemic regions, and gives rise to novel local SDSE variants, some of which may have increased fitness or pathogenic potential.

  19. Status and distribution of endemic and threatened birds of the Eastern Himalaya in Sikkim, India

    Directory of Open Access Journals (Sweden)

    B.K. Acharya

    2010-02-01

    Full Text Available Due to their restricted distribution range and dwindling population endemic and threatened species need considerable attention from ecologists. Sikkim is a part of the Eastern Himalayas Endemic Bird Area that represents high concentrations of globally threatened species. This study collected information on endemic and threatened birds of Sikkim using point count method. The number of species and their density at five elevation zones were calculated. Out of 10 species endemic to Sikkim, five were recorded during the present study. These species were restricted to one to three habitats but densities varied among the habitats. Similarly, out of 17 threatened and 10 near-threatened species of birds that occur in Sikkim, we could observe only three species. The results show that these birds are rare or their occurrence is doubtful in recent years. The principal threat to birds in the state appears to be loss of breeding habitat. Species-specific studies focusing on population status, habitat requirements and assessment of threats are necessary for the execution of conservation measures.

  20. Properties of middle-late Proterozoic volcanic rocks in South Qinling and the Precambrian continental break-up

    Institute of Scientific and Technical Information of China (English)

    夏林圻; 夏祖春; 徐学义

    1996-01-01

    In South Qinling, the volcanic series of the middle-late Proterozoic Yunxi Group, Yaolinghe Group, Xi.xiang Group and Bikou Group have characteristics of the continental rift volcanic rocks or continental flood basalts and are formed in continental intraplate tensional setting. The enrichment of incompatible elements, high εNd values and low-medium 87Sr/86Sr initial ratios of these volcanic rocks indicate that they were derived from asthenospheric plume. Under the action of the intense pull-apart in lithosphere, the mantle plume upwelled, quickly decompressed and melted, and finally produced magma. This tensional process made the continental crust break and eventually led to an oceanic basin in late Proterozoic. The middle-late Proterozoic volcanism is a precursor of Precarabrian continental break-up in the South Qinling.

  1. Australian Continental Shelf as an Inverse Estuary

    Science.gov (United States)

    Mahjabin, T.; Pattiaratchi, C. B.; Hetzel, Y.

    2016-02-01

    Transport of inshore waters and suspended material off the continental shelf by Dense Shelf Water Cascades (DSWC) has important ecological and biogeochemical implications in Australian waters. Because of high rates of evaporation, denser saline water along the sea bed occurs in a majority of the shallow coastal regions around Australia, setting up horizontal density gradients that can form DSWC. This study uses data available from the Integrated Marine Observing System (IMOS), which is operated by the Australian National Facility for Ocean Gliders (ANFOG) located at the University of Western Australia, to measure cross-shelf density profiles under varying conditions around the entire continent. Analysis of 143 transects of 97 sets of spatial and temporal resolution data from the ocean gliders under varying wind and tide conditions for seven contrasting regions surrounding Australia has allowed us to confirm that DSWC occurs on a regular basis during autumn and winter seasons. Results indicate that cascades occur during these seasons mainly due to cooling of the coastal water which already have higher salinity due to evaporation during the summer months. The cascades were present under different wind and tidal energy conditions and the controlling parameter for cascade formation is the cross-shelf density gradient. The cross-shelf density gradient in North-West Australia is maximum in July (14.23x10-6 kgm-4); whereas it is a maximum in June in South Australia (18.78x10-6 kgm-4) and in May in South-West Australia (25.884x10-6 kgm-4). Greater knowledge of the occurrence of DSWC will enhance understanding of the offshore transport of larvae, nutrients, salt, heat, carbon, low-oxygen water, sediment, and pollutants in Australian waters.

  2. Value of routine dengue diagnosis in endemic countries

    Science.gov (United States)

    Ayukekbong, James Ayukepi; Oyero, Olufunmilayo G; Nnukwu, Samuel Ekpesu; Mesumbe, Henry Nzike; Fobisong, Cajetang Nkong

    2017-01-01

    Dengue is one of the most common arthropod-borne viral diseases in humans and it is a leading cause of illness and death in the tropical and subtropical regions of the world. It is thought to account for 400 million cases annually among approximately 3.97 billion people at risk of infection in 128 endemic countries. Despite the global prevalence of the disease, the availability of a vaccine is limited in most countries in the endemic areas. Most endemic countries in South America, South East Asia and Africa serve as attractive touristic sites for people from non-endemic countries who become infected and export the virus to dengue-free regions. Dengue fever typically resembles malaria and in endemic countries most cases of dengue are treated as presumptive malaria. Consequently, routine dengue diagnosis among persons with fever will offer early treatment and reduce the burden of the disease. Also, routine testing among travellers from endemic countries will reduce importation and prevent the geographical expansion of dengue. In this essay, we seek to highlight the usefulness of routine dengue testing in endemic countries. PMID:28239567

  3. Human and animal fasciolasis in Peru: impact in the economy of endemic zones

    OpenAIRE

    Espinoza, José R.; Laboratorios de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Lima, Perú. Biólogo.; Terashima, Angélica; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú. Departamento de Enfermedades Infecciosas, Tropicales y Dermatológicas, Hospital Nacional Cayetano Heredia, Lima, Perú. Médica Parasitóloga.; Herrera-Velit, Patricia; Laboratorios de Investigación y Desarrollo, Universidad Peruana Cayetano Heredia, Lima, Perú. Biólogo.; Marcos, Luis A.; Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Perú. Infectious Diseases Division, School of Medicine, Washington University, St. Louis, MO, USA. Médico Infectólogo.

    2010-01-01

    Fasciola hepatica is the causative agent of fasciolosis in Peru; the disease is an important public health problem by the high prevalence of the human infection affecting mainly children and a major veterinary problem by the high rates of infected livestock. The human disease is endemic in the Sierra and the Coast but sporadic in the Amazonia, and reported in 18 Departments, while the animal infection in 21 of 24 Departments of Peru. Transmission occurs in Andean rural populations engaged...

  4. Plate Tectonics and Continental Drift: Classroom Ideas.

    Science.gov (United States)

    Stout, Prentice K.

    1983-01-01

    Suggests various classroom studies related to plate tectonics and continental drift, including comments on and sources of resource materials useful in teaching the topics. A complete list of magazine articles on the topics from the Sawyer Marine Resource Collection may be obtained by contacting the author. (JN)

  5. InterContinental Cuisine for Charity 2011

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Cuisine for Charity is one of the most important annual events for InterContinental Hotels Group (IHG) hotels in Beijing. It is a good opportunity not only for chefs to showcase them-selves, learn from each other and improve their cooking skills, but also to show that we take care of our social responsibilities.

  6. Elephant teeth from the atlantic continental shelf

    Science.gov (United States)

    Whitmore, F.C.; Emery, K.O.; Cooke, H.B.S.; Swift, D.J.P.

    1967-01-01

    Teeth of mastodons and mastodons have been recovered by fishermen from at least 40 sites on the continental shelf as deep as 120 meters. Also present are submerged shorelines, peat deposits, lagoonal shells, and relict sands. Evidently elephants and other large mammals ranged this region during the glacial stage of low sea level of the last 25.000 years.

  7. 25 years of continental deep subduction

    Institute of Scientific and Technical Information of China (English)

    ZHENG YongFei

    2009-01-01

    @@ This year marks the 25th anniversary of the discovery of coesite in metamorphic rocks of supracrustal origin.This initiated a revolution of the plate tectonics theory due to intensive studies of ultrahigh pressure metamorphism and continental deep subduction.The occurrence of coesite was first reported in 1984 by two French scientists,C.Chopin and D.C.Smith,respectively.

  8. Western Ross Sea continental slope gravity currents

    Science.gov (United States)

    Gordon, Arnold L.; Orsi, Alejandro H.; Muench, Robin; Huber, Bruce A.; Zambianchi, Enrico; Visbeck, Martin

    2009-06-01

    Antarctic Bottom Water of the world ocean is derived from dense Shelf Water that is carried downslope by gravity currents at specific sites along the Antarctic margins. Data gathered by the AnSlope and CLIMA programs reveal the presence of energetic gravity currents that are formed over the western continental slope of the Ross Sea when High Salinity Shelf Water exits the shelf through Drygalski Trough. Joides Trough, immediately to the east, offers an additional escape route for less saline Shelf Water, while the Glomar Challenger Trough still farther east is a major pathway for export of the once supercooled low-salinity Ice Shelf Water that forms under the Ross Ice Shelf. The Drygalski Trough gravity currents increase in thickness from ˜100 to ˜400 m on proceeding downslope from ˜600 m (the shelf break) to 1200 m (upper slope) sea floor depth, while turning sharply to the west in response to the Coriolis force during their descent. The mean current pathway trends ˜35° downslope from isobaths. Benthic-layer current and thickness are correlated with the bottom water salinity, which exerts the primary control over the benthic-layer density. A 1-year time series of bottom-water current and hydrographic properties obtained on the slope near the 1000 m isobath indicates episodic pulses of Shelf Water export through Drygalski Trough. These cold (34.75) pulses correlate with strong downslope bottom flow. Extreme examples occurred during austral summer/fall 2003, comprising concentrated High Salinity Shelf Water (-1.9 °C; 34.79) and approaching 1.5 m s -1 at descent angles as large as ˜60° relative to the isobaths. Such events were most common during November-May, consistent with a northward shift in position of the dense Shelf Water during austral summer. The coldest, saltiest bottom water was measured from mid-April to mid-May 2003. The summer/fall export of High Salinity Shelf Water observed in 2004 was less than that seen in 2003. This difference, if real

  9. Costs of Illness Due to Endemic Cholera

    Science.gov (United States)

    Poulos, C.; Riewpaiboon, A.; Stewart, J.F.; Clemens, J.; Guh, S.; Agtini, M.; Sur, D.; Islam, Z.; Lucas, M.; Whittington, D.

    2013-01-01

    Summary Economic analyses of cholera immunization programmes require estimates of the costs of cholera. The Diseases of the Most Impoverished programme measured the public, provider, and patient costs of culture-confirmed cholera in four study sites with endemic cholera using a combination of hospital- and community-based studies. Families with culture-proven cases were surveyed at home 7 and 14 days after confirmation of illness. Public costs were measured at local health facilities using a micro-costing methodology. Hospital-based studies found that the costs of severe cholera were USD 32 and 47 in Matlab and Beira. Community-based studies in North Jakarta and Kolkata found that cholera cases cost between USD 28 and USD 206, depending on hospitalization. Patient costs of illness as a percentage of average monthly income were 21% and 65% for hospitalized cases in Kolkata and North Jakarta, respectively. This burden on families is not captured by studies that adopt a provider perspective. PMID:21554781

  10. Characterization of colostrum from dams of BLV endemic dairy herds.

    Science.gov (United States)

    Gutiérrez, Gerónimo; Lomonaco, Marina; Alvarez, Irene; Fernandez, Fernando; Trono, Karina

    2015-06-12

    Bovine Leukemia Virus (BLV) is endemic in Argentina, where the individual prevalence is higher than 80% in dairy farms. The aim of this work was to find preliminary evidence to know if the high level of infection of the dam would implicate a higher challenge to her own offspring. We collected 65 sets of samples consisting of dam's blood and colostrum from two heavily infected dairy farms, and investigated the correlation between the dam's blood proviral load and the presence of provirus in colostrum. We also described the dual antibody/provirus profile in the colostrum. Provirus was detected in 69.23% of the colostrum samples, mostly from dams with a high proviral load, 36/45 (80%). Colostrum proviral load was significantly higher in dams with high blood proviral load (pcolostrum samples all along the antibody distribution, even in those with a low amount of antibodies. These results show that even when high blood proviral load dams offer higher levels of infected cells to their offspring through colostrum they also offer higher levels of protection of antibodies. On the contrary, low blood proviral load dams also offer infected cells but a poor content of antibodies, suggesting that these animals could play an important role in the epidemiological cycle of transmission.

  11. Tectonics and melting in intra-continental settings

    NARCIS (Netherlands)

    Gorczyk, Weronika; Vogt, Katharina

    2015-01-01

    Most of the geodynamic theories of deformation aswell asmetamorphismandmelting of continental lithosphere are concentrated on plate boundaries and are dominated by the effects of subduction upon deformation of the margins of continental lithospheric blocks. However, it is becoming increasingly

  12. Federal Outer Continental Shelf Oil and Gas Production Statistics

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — Federal Outer Continental Shelf Oil and Gas Production Statistics by month and summarized annually. Outer Continental Shelf consists of Gulf of Mexico, Pacific and...

  13. Tectonics and melting in intra-continental settings

    NARCIS (Netherlands)

    Gorczyk, Weronika; Vogt, Katharina|info:eu-repo/dai/nl/370618947

    2015-01-01

    Most of the geodynamic theories of deformation aswell asmetamorphismandmelting of continental lithosphere are concentrated on plate boundaries and are dominated by the effects of subduction upon deformation of the margins of continental lithospheric blocks. However, it is becoming increasingly appar

  14. Tectonics and melting in intra-continental settings

    NARCIS (Netherlands)

    Gorczyk, Weronika; Vogt, Katharina

    2015-01-01

    Most of the geodynamic theories of deformation aswell asmetamorphismandmelting of continental lithosphere are concentrated on plate boundaries and are dominated by the effects of subduction upon deformation of the margins of continental lithospheric blocks. However, it is becoming increasingly appar

  15. A comparison of urinary tract pathology and morbidity in adult populations from endemic and non-endemic zones for urinary schistosomiasis on Unguja Island, Zanzibar

    Directory of Open Access Journals (Sweden)

    Khamis Simba

    2009-11-01

    Full Text Available Abstract Background Renal tract involvement is implicated in both early and late schistosomiasis leading to increased disease burden. Despite there being good estimates of disease burden due to renal tract disease secondary to schistosomiasis at the global level, it is often difficult to translate these estimates into local communities. The aim of this study was to assess the burden of urinary tract pathology and morbidity due to schistosomiasis in Zanzibar and identify reliable clinical predictors of schistosomiasis associated renal disease. Methods A cross-sectional comparison of Ungujan men and women living within either high or low endemic areas for urinary schistosomiasis was conducted. Using urine analysis with reagent strips, parasitological egg counts, portable ultrasonography and a qualitative case-history questionnaire. Data analysis used single and multiple predictor variable logistic regression. Results One hundred and sixty people were examined in the high endemic area (63% women and 37% men, and 101 people in the low endemic area (61% women and 39% men. In the high endemic area, egg-patent schistosomiasis and urinary tract pathology were much more common (p = 1 × 10-3, 8 × 10-6, respectively in comparison with the low endemic area. Self-reported frothy urine, self-reported haematuria, dysuria and urgency to urinate were associated with urinary tract pathology (p = 1.8 × 10-2, p = 1.1 × 10-4, p = 1.3 × 10-6, p = 1.1 × 10-7, respectively as assessed by ultrasonography. In a multi-variable logistic regression model, self-reporting of schistosomiasis in the past year, self-reporting of urgency to urinate and having an egg-positive urine sample were all independently associated with detectable urinary tract abnormality, consistent with schistosomiasis-specific disease. Having two or more of these features was moderately sensitive (70% as a predictor for urinary tract abnormality with high specificity (92%. Conclusion Having two

  16. A comparison of urinary tract pathology and morbidity in adult populations from endemic and non-endemic zones for urinary schistosomiasis on Unguja Island, Zanzibar

    Science.gov (United States)

    2009-01-01

    Background Renal tract involvement is implicated in both early and late schistosomiasis leading to increased disease burden. Despite there being good estimates of disease burden due to renal tract disease secondary to schistosomiasis at the global level, it is often difficult to translate these estimates into local communities. The aim of this study was to assess the burden of urinary tract pathology and morbidity due to schistosomiasis in Zanzibar and identify reliable clinical predictors of schistosomiasis associated renal disease. Methods A cross-sectional comparison of Ungujan men and women living within either high or low endemic areas for urinary schistosomiasis was conducted. Using urine analysis with reagent strips, parasitological egg counts, portable ultrasonography and a qualitative case-history questionnaire. Data analysis used single and multiple predictor variable logistic regression. Results One hundred and sixty people were examined in the high endemic area (63% women and 37% men), and 101 people in the low endemic area (61% women and 39% men). In the high endemic area, egg-patent schistosomiasis and urinary tract pathology were much more common (p = 1 × 10-3, 8 × 10-6, respectively) in comparison with the low endemic area. Self-reported frothy urine, self-reported haematuria, dysuria and urgency to urinate were associated with urinary tract pathology (p = 1.8 × 10-2, p = 1.1 × 10-4, p = 1.3 × 10-6, p = 1.1 × 10-7, respectively) as assessed by ultrasonography. In a multi-variable logistic regression model, self-reporting of schistosomiasis in the past year, self-reporting of urgency to urinate and having an egg-positive urine sample were all independently associated with detectable urinary tract abnormality, consistent with schistosomiasis-specific disease. Having two or more of these features was moderately sensitive (70%) as a predictor for urinary tract abnormality with high specificity (92%). Conclusion Having two out of urgency to urinate

  17. Fighting leprosy and other endemic diseases.

    Science.gov (United States)

    Convit, Jacinto

    2002-07-01

    As part of its 100th-anniversary celebration, the Pan American Health Organization has named 12 persons as "Public Health Heroes of the Americas" in recognition of their noteworthy contributions to public health in the Region of the Americas. Over the course of this year, the Revista Panamericana de Salud Pública/Pan American Journal of Public Health will be carrying pieces written by or about these heroes. Como parte de la celebración de su Centenario, la Organización Panamericana de la Salud (OPS) ha distinguido con el título de Héroes de la Salud Pública a 12 personalidades que se han destacado por su valiosa contribución a la salud en el continente americano. A lo largo de este año, la Revista Panamericana de Salud Pública/Pan American Journal of Public Health publicará una serie de escritos de los mismos galardonados o acerca de ellos.

  18. Cellular and Molecular Defects Underlying Invasive Fungal Infections—Revelations from Endemic Mycoses

    Directory of Open Access Journals (Sweden)

    Pamela P. Lee

    2017-06-01

    Full Text Available The global burden of fungal diseases has been increasing, as a result of the expanding number of susceptible individuals including people living with human immunodeficiency virus (HIV, hematopoietic stem cell or organ transplant recipients, patients with malignancies or immunological conditions receiving immunosuppressive treatment, premature neonates, and the elderly. Opportunistic fungal pathogens such as Aspergillus, Candida, Cryptococcus, Rhizopus, and Pneumocystis jiroveci are distributed worldwide and constitute the majority of invasive fungal infections (IFIs. Dimorphic fungi such as Histoplasma capsulatum, Coccidioides spp., Paracoccidioides spp., Blastomyces dermatiditis, Sporothrix schenckii, Talaromyces (Penicillium marneffei, and Emmonsia spp. are geographically restricted to their respective habitats and cause endemic mycoses. Disseminated histoplasmosis, coccidioidomycosis, and T. marneffei infection are recognized as acquired immunodeficiency syndrome (AIDS-defining conditions, while the rest also cause high rate of morbidities and mortalities in patients with HIV infection and other immunocompromised conditions. In the past decade, a growing number of monogenic immunodeficiency disorders causing increased susceptibility to fungal infections have been discovered. In particular, defects of the IL-12/IFN-γ pathway and T-helper 17-mediated response are associated with increased susceptibility to endemic mycoses. In this review, we put together the various forms of endemic mycoses on the map and take a journey around the world to examine how cellular and molecular defects of the immune system predispose to invasive endemic fungal infections, including primary immunodeficiencies, individuals with autoantibodies against interferon-γ, and those receiving biologic response modifiers. Though rare, these conditions provide importance insights to host defense mechanisms against endemic fungi, which can only be appreciated in unique

  19. Thermochemical structure of the Earth's mantle and continental crust

    DEFF Research Database (Denmark)

    Guerri, Mattia

    task. In this thesis, I adopt a multidisciplinary approach geared towards the unification of geochemical and geophysical constraints within a framework provided by theoretical and experimental mineral and rock physics. In the first part, I focus on the Continental crust, assessing the relations between...... elastic properties and chemical composition taking into account the thermal and pressure effects. I found that even small amounts of H2O have an extremely high impact on the elastic properties of crustal rock. In addition, I show the potential that modifications in the stable mineralogical assemblage have...

  20. “Darwin’s butterflies”? DNA barcoding and the radiation of the endemic Caribbean butterfly genus Calisto (Lepidoptera, Nymphalidae, Satyrinae

    Directory of Open Access Journals (Sweden)

    Andrei Sourakov

    2011-08-01

    Clench, 1944, stat. n. should be treated as a single polytypic species, as genetic divergence among sampled populations representing these taxa is low (and stable morphological apomorphies are absent. A widely-distributed pest of sugar cane, Calisto pulchella Lathy, 1899 showed higher diversification among isolated populations (3.5% than expected, hence supporting former separation of this species into two taxa (pulchella and darlingtoni Clench, 1943, of which the latter might prove to be a separate species rather than subspecies. The taxonomic revisions presented here result in Calisto now containing 34 species and 17 subspecies. Three species endemic to islands other than Hispaniola appear to be derived lineages of various Hispaniolan clades, indicating ancient dispersal events from Hispaniola to Puerto Rico, Cuba, and Jamaica. Overall, the degree of intrageneric and intraspecific divergence within Calisto suggests a long and continuous diversification period of 4–8 Myr. The maximum divergence within the genus (ca. 13.3% is almost equivalent to the maximum divergence of Calisto from the distant pronophiline relative Auca Hayward, 1953 from the southern Andes (14.1% and from the presumed closest relative Eretris Thieme, 1905 (14.4%, suggesting that the genus began to diversify soon after its split from its continental sister taxon. In general, this ‘barcode’ divergence corresponds to the high degree of morphological and ecological variation found among major lineages within the genus.

  1. "Darwin's butterflies"? DNA barcoding and the radiation of the endemic Caribbean butterfly genus Calisto (Lepidoptera, Nymphalidae, Satyrinae).

    Science.gov (United States)

    Sourakov, Andrei; Zakharov, Evgeny V

    2011-01-01

    ., and Calisto grannus micheneri Clench, 1944, stat. n.) should be treated as a single polytypic species, as genetic divergence among sampled populations representing these taxa is low (and stable morphological apomorphies are absent). A widely-distributed pest of sugar cane, Calisto pulchella Lathy, 1899 showed higher diversification among isolated populations (3.5%) than expected, hence supporting former separation of this species into two taxa (pulchella and darlingtoni Clench, 1943), of which the latter might prove to be a separate species rather than subspecies. The taxonomic revisions presented here result in Calisto now containing 34 species and 17 subspecies. Three species endemic to islands other than Hispaniola appear to be derived lineages of various Hispaniolan clades, indicating ancient dispersal events from Hispaniola to Puerto Rico, Cuba, and Jamaica. Overall, the degree of intrageneric and intraspecific divergence within Calisto suggests a long and continuous diversification period of 4-8 Myr. The maximum divergence within the genus (ca. 13.3%) is almost equivalent to the maximum divergence of Calisto from the distant pronophiline relative Auca Hayward, 1953 from the southern Andes (14.1%) and from the presumed closest relative Eretris Thieme, 1905 (14.4%), suggesting that the genus began to diversify soon after its split from its continental sister taxon. In general, this 'barcode' divergence corresponds to the high degree of morphological and ecological variation found among major lineages within the genus.

  2. 78 FR 32183 - Importation of Avocados From Continental Spain

    Science.gov (United States)

    2013-05-29

    ... Continental Spain AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Proposed rule; reopening... allow the importation of avocados from continental Spain (excluding the Balearic Islands and Canary... vegetables regulations to allow the importation of avocados from continental Spain (excluding the...

  3. 78 FR 32184 - Importation of Fresh Apricots From Continental Spain

    Science.gov (United States)

    2013-05-29

    ... From Continental Spain AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Proposed rule... allow the importation into the United States of fresh apricots from continental Spain. This action will... of fresh apricots from continental Spain into the United States subject to a systems approach...

  4. "Work Hard, Fly Bight"——Today's Continental Airlines

    Institute of Scientific and Technical Information of China (English)

    Guo Yan

    2006-01-01

    @@ On June16, 2006, Continental Airlines celebrated the first anniversary of its daily nonstop flight from Beifing to New York. China's Foreign Trade exclusively interviewed Kwok Hing-Cheong, Chief Representative & Country Director-Continental Airlines, China. He talked about the developments, challenges and benefits of Continental Airlines in China.

  5. 49 CFR 192.10 - Outer continental shelf pipelines.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Outer continental shelf pipelines. 192.10 Section... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS General § 192.10 Outer continental shelf pipelines. Operators of transportation pipelines on the Outer Continental Shelf (as defined in...

  6. 49 CFR 195.9 - Outer continental shelf pipelines.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Outer continental shelf pipelines. 195.9 Section... HAZARDOUS LIQUIDS BY PIPELINE General § 195.9 Outer continental shelf pipelines. Operators of transportation pipelines on the Outer Continental Shelf must identify on all their respective pipelines the specific...

  7. 75 FR 1076 - Outer Continental Shelf Civil Penalties

    Science.gov (United States)

    2010-01-08

    ...: 2010-119] DEPARTMENT OF THE INTERIOR Minerals Management Service Outer Continental Shelf Civil... maximum daily civil penalty assessment. SUMMARY: The Outer Continental Shelf Lands Act requires the MMS to... operations in the Outer Continental Shelf at least once every 3 years. This review ensures that the...

  8. Generation of continental adakitic rocks: Crystallization modeling with variable bulk partition coefficients

    Science.gov (United States)

    Dai, Hong-Kun; Zheng, Jianping; Zhou, Xiang; Griffin, W. L.

    2017-02-01

    The geochemical signatures (i.e., high Sr/Y and La/Yb ratios) of adakitic rocks in continental settings, which are derived from the continental lower crust rather than from subducted slabs, may reflect high-pressure melting in the lower crust or may be inherited from their sources. The North China Craton (NCC) is an ideal place for investigation of this type of adakites due to its ubiquitous distribution. As an example, we explore the petrogenesis of the Jurassic ( 163 Ma) adakitic rocks in western Liaoning, in the NE part of the NCC, using elemental and Sr-Nd isotopic analysis and crystallization modeling based on Rhyolite-MELTS. The modeling demonstrates that adakitic signatures can be generated by fractional crystallization of magmas within crust of normal thickness (i.e., 33 km). Partial-melting modeling based on the composition of the lower continental crust shows that only the adakitic rocks from orogenic belts require a thickened crust (i.e., 45 km). We suggest that continental adakitic rocks are not necessarily linked to high-pressure processes and their use as an indicator of thickened/delaminated continental crust should be regarded with caution.

  9. Occurrence of gas hydrates along the continental margins of India, particularly the Krishna-Godavari offshore basin

    Digital Repository Service at National Institute of Oceanography (India)

    Ramana, M.V.; Ramprasad, T.; KameshRaju, K.A.; Desa, M.

    carried out in the Krishna-Godavari offshore area along the eastern continental margin of India, which is known for its hydrocarbon potential. Processed multibeam data provided a high-resolution seafloor mosaic with a fine scale geomorphology. Deep tow...

  10. Subduction and exhumation of continental crust: insights from laboratory models

    Science.gov (United States)

    Bialas, Robert W.; Funiciello, Francesca; Faccenna, Claudio

    2011-01-01

    When slivers of continental crust and sediment overlying oceanic lithosphere enter a subduction zone, they may be scraped off at shallow levels, subducted to depths of up to 100-200 km and then exhumed as high pressure (HP) and ultra-high pressure (UHP) rocks, or subducted and recycled in the mantle. To investigate the factors that influence the behaviour of subducting slivers of continental material, we use 3-D dynamically consistent laboratory models. A laboratory analogue of a slab-upper mantle system is set up with two linearly viscous layers of silicone putty and glucose syrup in a tank. A sliver of continental material, also composed of silicone putty, overlies the subducting lithosphere, separated by a syrup detachment. The density of the sliver, viscosity of the detachment, geometry of the subducting system (attached plate versus free ridge) and dimensions of the sliver are varied in 34 experiments. By varying the density of the sliver and viscosity of the detachment, we can reproduce a range of sliver behaviour, including subduction, subduction and exhumation from various depths and offscraping. Sliver subduction and exhumation requires sufficient sliver buoyancy and a detachment that is strong enough to hold the sliver during initial subduction, but weak enough to allow adequate sliver displacement or detachment for exhumation. Changes to the system geometry alter the slab dip, subduction velocity, pattern of mantle flow and amount of rollback. Shallower slab dips with more trench rollback produce a mantle flow pattern that aids exhumation. Steeper slab dips allow more buoyancy force to be directed in the up-dip direction of the plane of the plate, and aide exhumation of subducted slivers. Slower subduction can also aide exhumation, but if slab dip is too steep or subduction too slow, the sliver will subduct to only shallow levels and not exhume. Smaller slivers are most easily subducted and exhumed and influenced by the mantle flow.

  11. Some observations on endemic macroalgae of the Southern Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Dhargalkar, V.K.; Abidi, S.A.H.

    The paper summarises current level of knowledge on the endemic Antarctic macroalgae. The macroalgal adaptation to low temperature, response to different photoperiod during the season, animal-macroalgal interaction and reproductive strategies...

  12. Aristolochic Acid and the Etiology of Endemic (Balkan) Nephropathy

    National Research Council Canada - National Science Library

    Arthur P. Grollman; Shinya Shibutani; Masaaki Moriya; Frederick Miller; Lin Wu; Ute Moll; Naomi Suzuki; Andrea Fernandes; Thomas Rosenquist; Zvonimir Medverec; Krunoslav Jakovina; Branko Brdar; Neda Slade; Robert J. Turesky; Angela K. Goodenough; Robert Rieger; Mato Vukelić; Bojan Jelaković

    2007-01-01

    Endemic (Balkan) nephropathy (EN), a devastating renal disease affecting men and women living in rural areas of Bosnia, Bulgaria, Croatia, Romania, and Serbia, is characterized by its insidious onset, invariable progression...

  13. Validation and pharmacokinetic application of a high-performance liquid chromatographic technique for determining the concentrations of amodiaquine and its metabolite in plasma of patients treated with oral fixed-dose amodiaquine-artesunate combination in areas of malaria endemicity.

    Science.gov (United States)

    Adedeji, Olumuyiwa N; Bolaji, Oluseye O; Falade, Catherine O; Osonuga, Odusoga A; Ademowo, Olusegun G

    2015-09-01

    Artemisinin-based combination therapies (ACTs) have been adopted by most African countries, including Nigeria, as first-line treatments for uncomplicated falciparum malaria. Fixed-dose combinations of these ACTs, amodiaquine-artesunate (FDC AQAS) and artemether-lumefantrine (AL), were introduced in Nigeria to improve compliance and achieve positive outcomes of malaria treatment. In order to achieve clinical success with AQAS, we developed and validated a simple and sensitive high-performance liquid chromatography (HPLC) method with UV detection for determination of amodiaquine (AQ) and desethylamodiaquine (DAQ) in plasma using liquid-liquid extraction of the drugs with diethyl ether following protein precipitation with acetonitrile. Chromatographic separation was achieved using an Agilent Zorbax C18 column and a mobile phase consisting of distilled water-methanol (80:20 [vol/vol]) with 2% (vol/vol) triethylamine, pH 2.2, at a flow rate of 1 ml/min. Calibration curves in spiked plasma were linear from 100 to 1,000 ng/ml (r > 0.99) for both AQ and DAQ. The limit of detection was 1 ng (sample size, 20 μl). The intra- and interday coefficients of variation at 150, 300, and 900 ng/ml ranged from 1.3 to 4.8%, and the biases were between 6.4 and 9.5%. The mean extraction recoveries of AQ and DAQ were 80.0% and 68.9%, respectively. The results for the pharmacokinetic parameters of DAQ following oral administration of FDC AQAS (612/200 mg) for 3 days in female and male patients with uncomplicated falciparum malaria showed that the maximum plasma concentrations (C max) (740 ± 197 versus 767 ± 185 ng/ml), areas under the plasma concentration-time curve (AUC) (185,080 ± 20,813 versus 184,940 ± 16,370 h · ng/ml), and elimination half-life values (T 1/2) (212 ± 1.14 versus 214 ± 0.84 h) were similar (P > 0.05).

  14. Endangered, rare and endemic medicinal plants of the Kopetdag

    OpenAIRE

    AKMURADOV ALLAMURAD; SHAIYMOV BABAGULY; HALMEDOV BAZAR; YAKUBOV ATABEG; HALLIYEVA GULYAIYM

    2016-01-01

    The article presents some information of the place of growing of the endangered, rare and endemic medicinal plants of the Kopetdag. A monitoring has been carried out and the bioecological peculiarities, resource characteristics and modern state of the natural population of the most important species have been studied. Some scientifically based ways of protection and introduction into culture have been worked out to preserve the endangered, rare and endemic medicinal plants of the region.

  15. Control and eradication of endemic infectious diseases in cattle

    DEFF Research Database (Denmark)

    Houe, Hans; Nielsen, Liza Rosenbaum; Nielsen, Søren Saxmose

    "Control and eradication of endemic infectious diseases in cattle" provides the key elements that should be addressed in the establishment of bovine disease control and eradication programmes. The book aims to reach a broad group of readers, including: students; professionals in veterinary practi......, industry and governmental institutions; researchers; and others involved in control and eradication of endemic diseases in livestock. Key elements range from socioeconomic aspects such as motivation; veterinary science (including assessment of biosecurity and establishment of test...

  16. Magma-compensated crustal thinning in continental rift zones.

    Science.gov (United States)

    Thybo, H; Nielsen, C A

    2009-02-12

    Continental rift zones are long, narrow tectonic depressions in the Earth's surface where the entire lithosphere has been modified in extension. Rifting can eventually lead to rupture of the continental lithosphere and creation of new oceanic lithosphere or, alternatively, lead to formation of wide sedimentary basins around failed rift zones. Conventional models of rift zones include three characteristic features: surface manifestation as an elongated topographic trough, Moho shallowing due to crustal thinning, and reduced seismic velocity in the uppermost mantle due to decompression melting or heating from the Earth's interior. Here we demonstrate that only the surface manifestation is observed at the Baikal rift zone, whereas the crustal and mantle characteristics can be ruled out by a new seismic profile across southern Lake Baikal in Siberia. Instead we observe a localized zone in the lower crust which has exceptionally high seismic velocity and is highly reflective. We suggest that the expected Moho uplift was compensated by magmatic intrusion into the lower crust, producing the observed high-velocity zone. This finding demonstrates a previously unknown role for magmatism in rifting processes with significant implications for estimation of stretching factors and modelling of sedimentary basins around failed rift structures.

  17. The impact of temperature and precipitation on blacklegged tick activity and Lyme disease incidence in endemic and emerging regions.

    Science.gov (United States)

    Burtis, James C; Sullivan, Patrick; Levi, Taal; Oggenfuss, Kelly; Fahey, Timothy J; Ostfeld, Richard S

    2016-11-25

    The incidence of Lyme disease shows high degrees of inter-annual variation in the northeastern United States, but the factors driving this variation are not well understood. Complicating matters, it is also possible that these driving factors may vary in regions with differing histories of Lyme disease endemism. We evaluated the effect of the number of hot (T > 25 °C), dry (precipitation = 0) days during the questing periods of the two immature Ixodes scapularis life stages (larval and nymphal) on inter-annual variation in Lyme disease incidence between 2000 and 2011 in long-term endemic versus recently endemic areas. We also evaluated the effect of summer weather on tick questing activity and the number of ticks found on small mammals between 1994 and 2012 on six sites in Millbrook, NY. The number of hot, dry days during the larval period of the previous year did not affect the human incidence of Lyme disease or the density of questing nymphs the following season. However, dry summer weather during the nymphal questing period had a significant negative effect on the incidence of Lyme disease in the long-term endemic areas, and on the density of questing nymphs. Summer weather conditions had a more pronounced effect on actively questing I. scapularis collected via dragging than on the number of ticks found feeding on small mammals. In recently endemic areas Lyme disease incidence increased significantly over time, but no trend was detected between disease incidence and dry summer weather. Recently endemic regions showed an increase in Lyme disease incidence over time, while incidence in long-term endemic regions appears to have stabilized. Only within the stabilized areas were we able to detect reduced Lyme disease incidence in years with hot, dry summer weather. These patterns were reflected in our field data, which showed that questing activity of nymphal I. scapularis was reduced by hot, dry summer weather.

  18. Contrasting patterns in lichen diversity in the continental and maritime Antarctic

    Science.gov (United States)

    Singh, Shiv Mohan; Olech, Maria; Cannone, Nicoletta; Convey, Peter

    2015-09-01

    Systematic surveys of the lichen floras of Schirmacher Oasis (Queen Maud Land, continental Antarctic), Victoria Land (Ross Sector, continental Antarctic) and Admiralty Bay (South Shetland Islands, maritime Antarctic) were compared to help infer the major factors influencing patterns of diversity and biogeography in the three areas. Biogeographic patterns were determined using a variety of multivariate statistical tools. A total of 54 lichen species were documented from Schirmacher Oasis (SO), 48 from Victoria Land (VL) and 244 from Admiralty Bay (AB). Of these, 21 species were common to all areas. Most lichens from the SO and VL areas were microlichens, the dominant genus being Buellia. In AB, in contrast, many macrolichens were also present and the dominant genus was Caloplaca. In SO and VL large areas lacked any visible lichen cover, even where the ground was snow-free in summer. Small-scale diversity patterns were present in AB, where the number of species and genera was greater close to the coast. Most species recorded were rare in the study areas in which they were present and endemic to Antarctica.

  19. The population dynamics of an endemic collectible cactus

    Science.gov (United States)

    Mandujano, María C.; Bravo, Yolotzin; Verhulst, Johannes; Carrillo-Angeles, Israel; Golubov, Jordan

    2015-02-01

    Astrophytum is one of most collected genera in the cactus family. Around the world several species are maintained in collections and yearly, several plants are taken from their natural habitats. Populations of Astorphytum capricorne are found in the northern Chihuahuan desert, Mexico, and as many endemic cactus species, it has a highly restricted habitat. We conducted a demographic study from 2008 to 2010 of the northern populations found at Cuatro Ciénegas, Mexico. We applied matrix population models, included simulations, life table response experiments and descriptions of the population dynamics to evaluate the current status of the species, and detect key life table stages and demographic processes. Population growth rate decreased in both years and only 4% individual mortality can be attributed to looting, and a massive effort is needed to increase seedling recruitment and reduce adult mortality. The fate of individuals differed between years even having the same annual rainfall mainly in accentuated stasis, retrogression and high mortality in all size classes, which coupled with low seed production, no recruitment and collection of plants are the causes contributing to population decline, and hence, increase the risk in which A. capricorne populations are found. Reintroduction of seedlings and lowering adult mortality are urgently needed to revert the alarming demographic condition of A. capricorne populations.

  20. The continental Permian-Triassic boundary in the Netherlands: Implications for the geomagnetic polarity time scale

    NARCIS (Netherlands)

    Szurlies, M.; Geluk, M.C.; Krijgsman, W.; Kürschner, W.M.

    2012-01-01

    In Central and NW Europe, the transition from the Permian to the Triassic (i.e., the Zechstein–Buntsandstein boundary interval) is developed mainly in red bed facies. This continental sedimentary succession is marked by relatively high sedimentation rates providing a high temporal resolution favorab

  1. Post-Gondwanan continental sedimentaiton, Limpopo region, southeastern Africa

    Science.gov (United States)

    Botha, G. A.; De Wit, M. C. J.

    1996-08-01

    generated off areas of high relief bedrock topography. The initiation of this period of sedimentation is poorly constrained, and one must look to continental/marine stratigraphic relationships below the Mozambique coastal plain and in the Zambezi valley for an indication of the maximum and minimum ages. The most commonly accepted period of accumulation is during the Middle to Late Cretaceous. Deposition apparently ceased during the Late Cretaceous with the formation of the thick silcrete layer associated with the 'African' landsurface during this long period of geomorphic stability prior to the Palaeocene. The Eocene marine transgression resulted in truncation of the Malonga Formation and deposition of littoral and estuarine sediments high against the Lebombo mountains.

  2. Changes in continental Europe water cycle in a changing climate

    Science.gov (United States)

    Rouholahnejad, Elham; Schirmer, Mario; Abbaspour, Karim

    2015-04-01

    Changes in atmospheric water vapor content provide strong evidence that the water cycle is already responding to a warming climate. According to IPCC's last report on Climate Change (AR5), the water cycle is expected to intensify in a warmer climate as the atmosphere can hold more water vapor. This changes the frequency of precipitation extremes, increases evaporation and dry periods, and effects the water redistribution in land. This process is represented by most global climate models (GCMs) by increased summer dryness and winter wetness over large areas of continental mid to high latitudes in the Northern Hemisphere, associated with a reduction in water availability at continental scale. Observing changes in precipitation and evaporation directly and at continental scale is difficult, because most of the exchange of fresh water between the atmosphere and the surface happens the oceans. Long term precipitation records are available only from over the land and there are no measurement of evaporation or redistribution of precipitation over the land area. On the other hand, understanding the extent of climate change effects on various components of the water cycle is of strategic importance for public, private sectors, and policy makers when it comes to fresh water management. In order to better understand the extent of climate change impacts on water resources of continental Europe, we developed a distributed hydrological model of Europe at high spatial and temporal resolution using the Soil and Water Assessment Tool (SWAT). The hydrological model was calibrated for 1970 to 2006 using daily observation of streamflow and nitrate loads from 360 gauging stations across Europe. A vegetation growth routine was added to the model to better simulate evapotranspiration. The model results were calibrated with available agricultural crop yield data from other sources. As of future climate scenarios, we used the ISI-MIP project results which provides bias-corrected climate

  3. Submarine landslides along the eastern Mediterranean Israeli continental slope

    Science.gov (United States)

    Reuven, Einav; Katz, Oded; Aharonov, Einat

    2013-04-01

    Numerous shallow submarine slope failures (scars and deposits) are observed in recent high resolution bathymetric grids of the continental slope off the Israeli eastern Mediterranean coast. The nature of these slope failures is currently not comprehensively understood as well as the question of whether the eastern Mediterranean continental slope is continuously or episodically unstable. We report here first steps towards understanding the present state of this submarine landslide system, which include mapping and analyzing the geology of the landslides and the hosting slopes. The continental slope extends from water depths of about 150 to more than 1000 meters with a slope of less than 5 degrees in general. Bathymetric grids with pixel resolution of 15 m till water depth of 700 m and 50 m till water depth of 1700 m were used. Analyzing the bathymetry revealed three main submarine surface features: (a) numerous shallow landslides, within the upper sequence of the post-Messenian sediments. Landslide widths range between hundreds to thousand of meters at the scar, with scar heights up to hundred meters. The toes of the landslides are not always mapable and lay up to a few kilometers down slope from the scar. Slope angles within the scars are 5 to more than15 degrees. At least two types of landslides were detected: presumably young slides with sharp scars, and presumably old slides with secondary slides and secondary drainage systems developed within the scar area; (b) a few kilometers long, north striking step-like lineaments. Step heights are up to 100 meters and the slopes are up to 20 degrees. The offset between parallel steps is less than a kilometer to a few kilometers. The steps are interpreted as surface expressions of growth faults rooted at the Messinian evaporates up to 1.5 kilometers below surface; (c) a few north striking channels were also detected with steep walls of more than 15 degrees, up to two kilometers width and a few kilometers length. The nature

  4. Moroccan crustal response to continental drift.

    Science.gov (United States)

    Kanes, W H; Saadi, M; Ehrlich, E; Alem, A

    1973-06-01

    The formation and development of a zone of spreading beneath the continental crust resulted in the breakup of Pangea and formation of the Atlantic Ocean. The crust of Morocco bears an extremely complete record of the crustal response to this episode of mantle dynamics. Structural and related depositional patterns indicate that the African margin had stabilized by the Middle Jurassic as a marine carbonate environment; that it was dominated by tensile stresses in the early Mesozoic, resulting in two fault systems paralleling the Atlantic and Mediterranean margins and a basin and range structural-depositional style; and that it was affected by late Paleozoic metamorphism and intrusion. Mesozoic events record the latter portion of African involvement in the spreading episode; late Paleozoic thermal orogenesis might reflect the earlier events in the initiation of the spreading center and its development beneath significant continental crust. In that case, more than 100 million years were required for mantle dynamics to break up Pangea.

  5. Regional magnetic anomaly constraints on continental rifting

    Science.gov (United States)

    Vonfrese, R. R. B.; Hinze, W. J.; Olivier, R.; Bentley, C. R.

    1985-01-01

    Radially polarized MAGSAT anomalies of North and South America, Europe, Africa, India, Australia and Antarctica demonstrate remarkably detailed correlation of regional magnetic lithospheric sources across rifted margins when plotted on a reconstruction of Pangea. These major magnetic features apparently preserve their integrity until a superimposed metamorphoric event alters the magnitude and pattern of the anomalies. The longevity of continental scale magnetic anomalies contrasts markedly with that of regional gravity anomalies which tend to reflect predominantly isostatic adjustments associated with neo-tectonism. First observed as a result of NASA's magnetic satellite programs, these anomalies provide new and fundamental constraints on the geologic evolution and dynamics of the continents and oceans. Accordingly, satellite magnetic observations provide a further tool for investigating continental drift to compliment other lines of evidence in paleoclimatology, paleontology, paleomagnetism, and studies of the radiometric ages and geometric fit of the continents.

  6. A new species of Uvariopsis (Annonaceae), endemic to the Eastern Arc Mountains of Tanzania

    OpenAIRE

    Couvreur, Th.L.P.; Luke, W.R.Q.

    2010-01-01

    The Eastern Arc Mountains of Tanzania enclose high levels of plant and animal diversity with many yet to be described species. Here we describe a new species of the pan-tropical plant family Annonaceae named Uvariopsis lovettiana. It closely resembles another Eastern Arc endemic species, U. bisexualis, and its possible relationships with this species are discussed. A description with illustrations is presented as well as a suggestion for the IUCN conservation status of this new taxon.

  7. Co-endemicity of Pulmonary Tuberculosis and Intestinal Helminth Infection in the People's Republic of China.

    Science.gov (United States)

    Li, Xin-Xu; Ren, Zhou-Peng; Wang, Li-Xia; Zhang, Hui; Jiang, Shi-Wen; Chen, Jia-Xu; Wang, Jin-Feng; Zhou, Xiao-Nong

    2016-03-01

    Both pulmonary tuberculosis (PTB) and intestinal helminth infection (IHI) affect millions of individuals every year in China. However, the national-scale estimation of prevalence predictors and prevalence maps for these diseases, as well as co-endemic relative risk (RR) maps of both diseases' prevalence are not well developed. There are co-endemic, high prevalence areas of both diseases, whose delimitation is essential for devising effective control strategies. Bayesian geostatistical logistic regression models including socio-economic, climatic, geographical and environmental predictors were fitted separately for active PTB and IHI based on data from the national surveys for PTB and major human parasitic diseases that were completed in 2010 and 2004, respectively. Prevalence maps and co-endemic RR maps were constructed for both diseases by means of Bayesian Kriging model and Bayesian shared component model capable of appraising the fraction of variance of spatial RRs shared by both diseases, and those specific for each one, under an assumption that there are unobserved covariates common to both diseases. Our results indicate that gross domestic product (GDP) per capita had a negative association, while rural regions, the arid and polar zones and elevation had positive association with active PTB prevalence; for the IHI prevalence, GDP per capita and distance to water bodies had a negative association, the equatorial and warm zones and the normalized difference vegetation index had a positive association. Moderate to high prevalence of active PTB and low prevalence of IHI were predicted in western regions, low to moderate prevalence of active PTB and low prevalence of IHI were predicted in north-central regions and the southeast coastal regions, and moderate to high prevalence of active PTB and high prevalence of IHI were predicted in the south-western regions. Thus, co-endemic areas of active PTB and IHI were located in the south-western regions of China, which

  8. Co-endemicity of Pulmonary Tuberculosis and Intestinal Helminth Infection in the People's Republic of China.

    Directory of Open Access Journals (Sweden)

    Xin-Xu Li

    2016-03-01

    Full Text Available Both pulmonary tuberculosis (PTB and intestinal helminth infection (IHI affect millions of individuals every year in China. However, the national-scale estimation of prevalence predictors and prevalence maps for these diseases, as well as co-endemic relative risk (RR maps of both diseases' prevalence are not well developed. There are co-endemic, high prevalence areas of both diseases, whose delimitation is essential for devising effective control strategies. Bayesian geostatistical logistic regression models including socio-economic, climatic, geographical and environmental predictors were fitted separately for active PTB and IHI based on data from the national surveys for PTB and major human parasitic diseases that were completed in 2010 and 2004, respectively. Prevalence maps and co-endemic RR maps were constructed for both diseases by means of Bayesian Kriging model and Bayesian shared component model capable of appraising the fraction of variance of spatial RRs shared by both diseases, and those specific for each one, under an assumption that there are unobserved covariates common to both diseases. Our results indicate that gross domestic product (GDP per capita had a negative association, while rural regions, the arid and polar zones and elevation had positive association with active PTB prevalence; for the IHI prevalence, GDP per capita and distance to water bodies had a negative association, the equatorial and warm zones and the normalized difference vegetation index had a positive association. Moderate to high prevalence of active PTB and low prevalence of IHI were predicted in western regions, low to moderate prevalence of active PTB and low prevalence of IHI were predicted in north-central regions and the southeast coastal regions, and moderate to high prevalence of active PTB and high prevalence of IHI were predicted in the south-western regions. Thus, co-endemic areas of active PTB and IHI were located in the south-western regions of

  9. Increased reports of measles in a low endemic region during a rubella outbreak in adult populations.

    Science.gov (United States)

    Kurata, Takako; Kanbayashi, Daiki; Nishimura, Hiroshi; Komano, Jun; Kase, Tetsuo; Takahashi, Kazuo

    2015-06-01

    In 2013, a rubella outbreak was observed in Japan, Romania, and Poland. The outbreak in Japan was accompanied by an increase of measles reports, especially from a region where measles is highly controlled. This was attributed to the adult populations affected by this rubella outbreak, similarity of clinical signs between rubella and measles, sufficiently small impact of measles outbreaks from neighboring nations, and elimination levels of measles endemicity. Current and future concerns for measles control are discussed.

  10. Geometries of hyperextended continental crust in northeastern continental brazilian margin: insights from potential field and seismic interpretation

    Science.gov (United States)

    Magalhães, José; Barbosa, José; Ribeiro, Vanessa; Oliveira, Jefferson; Filho, Osvaldo; Buarque, Bruno

    2016-04-01

    The study region encompasses a set of three basins located at Northeast Brazilian continental margin: Pernambuco (south sector), Paraíba and Natal platform (north sector). These basins were formed during the last stage of separation between South America and African plates during Cretaceous. The continental breakup in these regions occurred probably during the Middle-Upper Albian (~102 m.y). The adjacent basement rocks belong to Borborema Province (BP), which was formed due a complex superposition between Pre-Cambrian orogenic cycles. The structural framework of BP is dominated by large shear zones that divided this province in three main tectonic domains: South, Central and North. The Pernambuco Basin is located in the South Domain and the Paraíba and Natal platform basins are related to the Central Domain. The tectonic and magmatic evolution of the Pernambuco Basin was influenced by oblique rifting (~ 35° to rift axis) and a thermal anomaly probably caused by the Santa Helena hotspot. The north sector represents a continental shelf characterized by basement high with a narrow platform and an abrupt shelf break on transition to the abyssal plain. The continental platform break of this sector was parallel to the rift axis. In this way, we present a regional structural interpretation of these sectors of Brazilian rifted margin based on interpretation and 2D forward modeling of potential field and 2D seismic data. The magnetic maps (Reduction to magnetic pole and Analytic signal) revealed the influence of an alternating pattern of large narrow magnetic and non-magnetic lineaments, oriented NE-SW, E-W and NW-SE. In the Pernambuco Basin these lineaments (NE-SW and E-W) are related to shear zones in the hyperextended basement which is interpreted as a continuation of the granitic-gneissic and metasedimentary rocks of the South Domain of BP. The Paraíba and Natal platform basins show a slight change in the orientation of structures trending E-W (shear zones in

  11. Reduction of spleen size in a child with Hyperreactive Malarious Splenomegaly (HMS treated outside the Brazilian endemic area of malaria with only one course of quinine

    Directory of Open Access Journals (Sweden)

    Maria Imaculada Muniz-Junqueira

    1992-12-01

    Full Text Available We report the clinical picture, treatment and evolution of a child with hyperreactive malarious splenomegaly treated outside the endemic area of malaria. The patient presented gross splenomegaly, proceeded from an area where malaria is endemic, showed increased immunoglobulins levels, high antimalarial antibody titres and hepatic sinusoidal lymphocytosis. The child did not return to an area where malaria is endemic and showed a favorable response to only one course of quinine. The response of this patient to limited antimalarial therapy suggests the importance of reinfection with malaria in the development and maintenance of this syndrome.

  12. Sustainable Offshore Wind Potential in Continental Portugal

    OpenAIRE

    Costa, P.; Simões, T. (Tânia); Estanqueiro, Ana

    2010-01-01

    This study intends to depict the availability of the sustainable offshore wind energy for Continental Portugal and identify the preliminary areas for developing offshore wind parks. Two scenarios were performed to distinct the different offshore wind turbine prototypes assembled by the manufactory energy sector – bottom fixed and floating models. The results achieved until now indicate that Portugal has a very large potential for offshore wind deployments ready to be exploited, especial...

  13. Authigenic minerals from the continental margins

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, V.P.

    phosphorites have been presumed to be sedimented plankton organic matter, fish debris, and iron-redox phosphate pump. Several workers investigated the genesis of sedimentary phosphorites occurring from Precambrian to Recent and proposed different...-phosphate sediments of the western continental margin of India showed that phosphate occurred as apatite microparticles that resembled fossilized phosphate bacteria and/or microbial filaments (Fig. 3). This established the prominence of micro- environments...

  14. Ocean processes at the Antarctic continental slope.

    Science.gov (United States)

    Heywood, Karen J; Schmidtko, Sunke; Heuzé, Céline; Kaiser, Jan; Jickells, Timothy D; Queste, Bastien Y; Stevens, David P; Wadley, Martin; Thompson, Andrew F; Fielding, Sophie; Guihen, Damien; Creed, Elizabeth; Ridley, Jeff K; Smith, Walker

    2014-07-13

    The Antarctic continental shelves and slopes occupy relatively small areas, but, nevertheless, are important for global climate, biogeochemical cycling and ecosystem functioning. Processes of water mass transformation through sea ice formation/melting and ocean-atmosphere interaction are key to the formation of deep and bottom waters as well as determining the heat flux beneath ice shelves. Climate models, however, struggle to capture these physical processes and are unable to reproduce water mass properties of the region. Dynamics at the continental slope are key for correctly modelling climate, yet their small spatial scale presents challenges both for ocean modelling and for observational studies. Cross-slope exchange processes are also vital for the flux of nutrients such as iron from the continental shelf into the mixed layer of the Southern Ocean. An iron-cycling model embedded in an eddy-permitting ocean model reveals the importance of sedimentary iron in fertilizing parts of the Southern Ocean. Ocean gliders play a key role in improving our ability to observe and understand these small-scale processes at the continental shelf break. The Gliders: Excellent New Tools for Observing the Ocean (GENTOO) project deployed three Seagliders for up to two months in early 2012 to sample the water to the east of the Antarctic Peninsula in unprecedented temporal and spatial detail. The glider data resolve small-scale exchange processes across the shelf-break front (the Antarctic Slope Front) and the front's biogeochemical signature. GENTOO demonstrated the capability of ocean gliders to play a key role in a future multi-disciplinary Southern Ocean observing system.

  15. Continental moisture recycling as a Poisson process

    OpenAIRE

    2013-01-01

    On their journey across large land masses, water molecules experience a number of precipitation-evaporation cycles (recycling events). We derive analytically the frequency distributions of recycling events for the water molecules contained in a given air parcel. Given the validity of certain simplifying assumptions, continental moisture recycling is shown to develop either into a Poisson distribution or a geometric distribution. We distinguish two cases: in case (A) recycling events a...

  16. Cyclic growth in Atlantic region continental crust

    Science.gov (United States)

    Goodwin, A. M.

    1986-01-01

    Atlantic region continental crust evolved in successive stages under the influence of regular, approximately 400 Ma-long tectonic cycles. Data point to a variety of operative tectonic processes ranging from widespread ocean floor consumption (Wilson cycle) to entirely ensialic (Ampferer-style subduction or simple crustal attenuation-compression). Different processes may have operated concurrently in some or different belts. Resolving this remains the major challenge.

  17. Continental crust formation on early Earth controlled by intrusive magmatism

    Science.gov (United States)

    Rozel, A. B.; Golabek, G. J.; Jain, C.; Tackley, P. J.; Gerya, T.

    2017-05-01

    The global geodynamic regime of early Earth, which operated before the onset of plate tectonics, remains contentious. As geological and geochemical data suggest hotter Archean mantle temperature and more intense juvenile magmatism than in the present-day Earth, two crust-mantle interaction modes differing in melt eruption efficiency have been proposed: the Io-like heat-pipe tectonics regime dominated by volcanism and the “Plutonic squishy lid” tectonics regime governed by intrusive magmatism, which is thought to apply to the dynamics of Venus. Both tectonics regimes are capable of producing primordial tonalite-trondhjemite-granodiorite (TTG) continental crust but lithospheric geotherms and crust production rates as well as proportions of various TTG compositions differ greatly, which implies that the heat-pipe and Plutonic squishy lid hypotheses can be tested using natural data. Here we investigate the creation of primordial TTG-like continental crust using self-consistent numerical models of global thermochemical convection associated with magmatic processes. We show that the volcanism-dominated heat-pipe tectonics model results in cold crustal geotherms and is not able to produce Earth-like primordial continental crust. In contrast, the Plutonic squishy lid tectonics regime dominated by intrusive magmatism results in hotter crustal geotherms and is capable of reproducing the observed proportions of various TTG rocks. Using a systematic parameter study, we show that the typical modern eruption efficiency of less than 40 per cent leads to the production of the expected amounts of the three main primordial crustal compositions previously reported from field data (low-, medium- and high-pressure TTG). Our study thus suggests that the pre-plate-tectonics Archean Earth operated globally in the Plutonic squishy lid regime rather than in an Io-like heat-pipe regime.

  18. Linking continental erosion to marine transport and sedimentation

    Science.gov (United States)

    Yuan, Xiaoping; Braun, Jean; Guerit, Laure

    2017-04-01

    Limited attention has been given to linking continental erosion to marine transport and sedimentation in large-scale landscape evolution models. Although either of the two environments has been thoroughly investigated, the details of how erosional events are recorded in the sedimentary and stratigraphic records have not been studied in a consistent quantitative manner. Here we present results obtained from a new numerical model for marine sediment transport and deposition that is directly coupled to FastScape, a landscape evolution model that solves the continental stream power law and hillslope diffusion equation using fully implicit and O(n) algorithms. The model of marine transport and sedimentation is simulated by a nonlinear 2D diffusion model where a source term represents mass flux arising from continental river erosion. It is based on the simplest representation of marine transport that assumes that flux is proportional to slope, which leads to a diffusion-type equation that we solve using an alternating direction implicit scheme. Multiple lithologies are implemented that vary by their transport coefficients. This method is also highly efficient (O(n) and implicit), which allows us to perform a large number of simulations to undertake a Bayesian inversion of stratigraphic data. Using our model we not only show the manner in which the stratigraphic record responds to tectonic and climate events but also how it is controlled by the coefficients for river erosion, hillslope diffusion, the transport coefficients in the ocean environment, and variations in sea level. The model is used to better constrain the nature and timing of erosional events on adjacent continents through an inversion of the stratigraphic record. In the longer term, we are looking at ways to improve the equations governing marine sediment transport especially, to better represent the deep part of that transport, i.e. in the abyssal plains or past the shelf and slope.

  19. Fluid migration in continental subduction: The Northern Apennines case study

    Science.gov (United States)

    Agostinetti, Nicola Piana; Bianchi, Irene; Amato, Alessandro; Chiarabba, Claudio

    2011-02-01

    Subduction zones are the place in the world where fluids are transported from the foredeep to the mantle and back-to-the-surface in the back-arc. The subduction of an oceanic plate implies the transportation of the oceanic crust to depth and its methamorphization. Oceanic sediments release water in the (relatively) shallower part of the subduction zone, while dehydration of the subducted basaltic crust allows fluid circulation at larger depths. While the water budget in oceanic subduction has been deeply investigated, less attention has been given to the fluids implied in the subduction of a continental margin (i.e. in continental subduction). In this study, we use teleseismic receiver function (RF) analysis to image the process of water migration at depth, from the subducting plate to the mantle wedge, under the Northern Apennines (NAP, Italy). Harmonic decomposition of the RF data-set is used to constrain both isotropic and anisotropic structures. Isotropic structures highlight the subduction of the Adriatic lower crust under the NAP orogens, from 35-40 km to 65 km depth, as a dipping low S-velocity layer. Anisotropic structures indicate the presence of a broad anisotropic zone (anisotropy as high as 7%). This zone develops in the subducted Adriatic lower crust and mantle wedge, between 45 and 65 km depth, directly beneath the orogens and the more recent back-arc extensional basin. The anisotropy is related to the metamorphism of the Adriatic lower crust (gabbro to blueschists) and its consequent eclogitization (blueschists to eclogite). The second metamorphic phase releases water directly in the mantle wedge, hydrating the back-arc upper mantle. The fluid migration process imaged in this study below the northern Apennines could be a proxy for understanding other regions of ongoing continental subduction.

  20. Continental crust formation on early Earth controlled by intrusive magmatism.

    Science.gov (United States)

    Rozel, A B; Golabek, G J; Jain, C; Tackley, P J; Gerya, T

    2017-05-18

    The global geodynamic regime of early Earth, which operated before the onset of plate tectonics, remains contentious. As geological and geochemical data suggest hotter Archean mantle temperature and more intense juvenile magmatism than in the present-day Earth, two crust-mantle interaction modes differing in melt eruption efficiency have been proposed: the Io-like heat-pipe tectonics regime dominated by volcanism and the "Plutonic squishy lid" tectonics regime governed by intrusive magmatism, which is thought to apply to the dynamics of Venus. Both tectonics regimes are capable of producing primordial tonalite-trondhjemite-granodiorite (TTG) continental crust but lithospheric geotherms and crust production rates as well as proportions of various TTG compositions differ greatly, which implies that the heat-pipe and Plutonic squishy lid hypotheses can be tested using natural data. Here we investigate the creation of primordial TTG-like continental crust using self-consistent numerical models of global thermochemical convection associated with magmatic processes. We show that the volcanism-dominated heat-pipe tectonics model results in cold crustal geotherms and is not able to produce Earth-like primordial continental crust. In contrast, the Plutonic squishy lid tectonics regime dominated by intrusive magmatism results in hotter crustal geotherms and is capable of reproducing the observed proportions of various TTG rocks. Using a systematic parameter study, we show that the typical modern eruption efficiency of less than 40 per cent leads to the production of the expected amounts of the three main primordial crustal compositions previously reported from field data (low-, medium- and high-pressure TTG). Our study thus suggests that the pre-plate-tectonics Archean Earth operated globally in the Plutonic squishy lid regime rather than in an Io-like heat-pipe regime.

  1. Abrupt plate accelerations shape rifted continental margins

    Science.gov (United States)

    Brune, Sascha; Williams, Simon E.; Butterworth, Nathaniel P.; Müller, R. Dietmar

    2016-08-01

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth’s major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength-velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time.

  2. Abrupt plate accelerations shape rifted continental margins.

    Science.gov (United States)

    Brune, Sascha; Williams, Simon E; Butterworth, Nathaniel P; Müller, R Dietmar

    2016-08-11

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth's major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength--velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time.

  3. Therapy of endemic goitre; Therapie der Jodmangelstruma

    Energy Technology Data Exchange (ETDEWEB)

    Leisner, B. [Allg. Krankenhaus St. Georg, Hamburg (Germany). Abt. fuer Nuklearmedizin

    1995-12-01

    1. In childhood the first line treatment of endemic goitre is Kl (100-150 {mu}g/day). Once the goitre volume has shrinked during L-thyroxine treatment in older patients, this effect is to be maintained by Kl ({proportional_to}200 {mu}g/day). The same holds true after surgery in cases with normal TSH responsiveness to TRH. 2. TSH suppressive L-thyroxine therapy is indicated in goitre patients older than 40 years. However, the effectiveness will be limited by the nodularity of the thyroid. So prevention of further growth prevails over true tissue reduction. 3. Obviously thyroid surgery yields the best cosmetic results with an acceptably low complication rate. When euthyroidism is established, a lifelong iodine prophylaxy (200 {mu}g/day) of recurrent goitre is mandatory. In cases with latent or overt hypothyroidism an appropriate therapy with thyroid hormone should be given. 4. By radiodine it is possible to realize a short term volume loss of 30-40% which may increase further on up to 60%. Relief of symptoms is usually even more impressive than actual volume loss. (orig./MG) [Deutsch] 1. Kaliumjodid ist heute das Mittel der Wahl zur Behandlung der Jodmangelstruma von Kindern (100 {mu}g) und Jugendlichen (150 {mu}g). Lebenslange Einnahme von Jodid (200 {mu}g) dient der Erhaltung einer Organverkleinerung, die durch L-Thyroxin bei aelteren Patienten erreicht wurde, und postoperativ bei gesicherter Euthyreose (TSH). In der Schwangerschaft ist eine Jodid-Medikation fuer Mutter und Kind erforderlich. 2. L-Thyroxin in TSH-suppressiver Dosierung sollte eingesetzt werden, wenn mit Jodid kein Verkleinerungseffekt erreichbar ist. Primaer ist es indiziert bei Patienten ueber 40 Jahren. Postoperativ muss L-Thyroxin dann verordnet werden, wenn eine latente oder manifeste Hypothyreose gesichert ist. Damit behandelt es sich aber nicht um eine Rezidiv-Prophylaxe im engeren Sinn. 3. Eine wirkliche Substanzverminderung des Kropfes gelingt durch die operative Resektion. Eine konsequente

  4. Testament's ability in Balkan endemic nephropathy

    Directory of Open Access Journals (Sweden)

    Novaković Milan

    2009-01-01

    Full Text Available Introduction Testament is a solemn, authentic instrument in writing, by which a person declares his or her will as to disposal of his or her estate, and it has a psychopathological, lawful and ethical importance to a person, family and society. The aim of the study was to assess if the ability to make a testament was more damaged in patients with Balkan Endemic Nephropathy (BEN than in patients with other diseases that resulted in Chronic Renal Failure in Bosnia and Herzegovina in the period from the 1st January 2001 to 31st December 2006. Material and methods The 753 respondents were divided into two groups in the study: BEN group (n=150 and control group made of patients with other diseases resulting in CRF (n=150. In a multicentric longitudinal study we used: adapted questionnaire from the Renal Register of Bosnia and Herzegovina, Hamilton Depression Rating Scale, and Mini-Mental State Examination. Descriptive analysis, discriminative function and regression model have been done statistically. Results In BEN group, heirs are mostly mentioned - 84.0% (t=14.391; P=0.001, and in control group: heirs - 66.6%, relatives - 43.3% (t=7.751; P=0.003, carers - 44.0% (t= 6.678 P=0.032, and institutions 10.0% (t=5.147, P=0.061. The discriminative function shows differences between BEN and control group: canonical correlation (rc =0.827, Wilkinson lambda (lnj =0.871, Chi-square test =141.575 and significance (P=0.001. The regression course of the analysis can be used for prediction of the ability to make testament for the patients on dialysis: [y=-0.95x + 15.715, and OR = 0.785, (95% for CI = -0.997 - -0.375; Can Fanc r2=0.861; Significance is P=0.002]. Conclusion The ability to make a testament is more damaged in patients from the nephropathy group than in the patients from the control group who are on dialysis in Bosnia and Herzegovina. This has been confirmed by socio-demographic and psychological parameters, and it is very important for preservation

  5. Hantavirus pulmonary syndrome in a highly endemic area of Brazil.

    Science.gov (United States)

    Oliveira, R C; Sant'ana, M M; Guterres, A; Fernandes, J; Hillesheim, N L F K; Lucini, C; Gomes, R; Lamas, C; Bochner, R; Zeccer, S; DE Lemos, E R S

    2016-04-01

    Hantavirus pulmonary syndrome (HPS) is the most frequently reported fatal rodent-borne disease in Brazil, with the majority of cases occurring in Santa Catarina. We analysed the clinical, laboratory and epidemiological data of the 251 confirmed cases of HPS in Santa Catarina in 1999-2011. The number of cases ranged from 10 to 47 per year, with the highest incidences in 2004-2006. Gastrointestinal tract manifestations were found in >60% of the cases, potentially confounding diagnosis and leading to inappropriate therapy. Dyspnoea, acute respiratory failure, renal failure, increased serum creatinine and urea levels, increased haematocrits and the presence of pulmonary interstitial infiltrate were significantly more common in HPS patients who died. In addition, we demonstrated that the six cases from the midwest region of the state were associated with Juquitiba virus genotype. The case-fatality rate in this region, 19·2%, was lower than that recorded for other mesoregions. In the multivariate analysis increase of serum creatinine and urea was associated with death by HPS. Our findings help elucidate the epidemiology of HPS in Brazil, where mast seeding of bamboo can trigger rodent population eruptions and subsequent human HPS outbreaks. We also emphasize the need for molecular confirmation of the hantavirus genotype of human cases for a better understanding of the mortality-related factors associated with HPS cases in Brazil.

  6. Ruthenium endemic isotope effects in chondrites and differentiated meteorites

    Science.gov (United States)

    Chen, J. H.; Papanastassiou, D. A.; Wasserburg, G. J.

    2010-07-01

    We report on the abundances of Ru isotopes in (1) iron meteorites, (2) stony-iron meteorites (pallasites), (3) ordinary and carbonaceous chondrites, and (4) in refractory inclusions from the carbonaceous meteorite Allende. We have developed improved Multiple-Collector, Negative-ion Thermal Ionization Mass Spectrometric (MC-NTIMS) techniques for Ru, with high ionization efficiency of 4% and with chemical separation techniques for Ru, which reduce mass interferences to the ppm level, so that no mass interference corrections needed to be applied. Our data were normalized to 99Ru/ 101Ru to correct for mass-dependent fractionation. We find no Ru isotopic effects in the ordinary chondrites and group IAB iron meteorites we have measured. There are significant effects (deficits) in the pure s-process nuclide 100Ru, in the Allende whole-rock and in refractory inclusions of up to 1.7 parts in 10,000 (ɛu). There are also endemic deficits in 100Ru in iron meteorites and in pallasites of up to 1.1 ɛu. The Ru data suggest a wide spread and large scale heterogeneity in p-, s-, and r-process components resulting in a deficit in s-process nuclides or enhancements in both p- and r-process nuclides, in refractory siderophiles condensing in the early solar nebula. In contrast, the data on bulk Murchison suggest an excess in 100Ru and in 104Ru, which are distinct from the rest of the measured patterns. Our results establish the presence of significant isotopic heterogeneity for Ru in the early solar nebula. The observation of endemic Ru effects in planetary differentiates, such as iron meteorites and pallasites, must reflect the siderophile nature of Ru and the preservation in condensing FeNi metal of refractory metal condensate grains formed in the early solar nebula. Once incorporated in the metal phase, the refractory siderophiles remained in the metal phase through the melting and differentiation of planetesimals to form FeNi cores and silicate mantles and crusts.

  7. FOSSO DELLA FITTAIA: THE OLDEST TUSCO-SARDINIAN LATE MIOCENE ENDEMIC VERTEBRATE ASSEMBLAGES (BACCINELLO-CINIGIANO BASIN, TUSCANY, ITALY

    Directory of Open Access Journals (Sweden)

    OMAR CIRILLI

    2016-05-01

    Full Text Available The late Miocene continental successions of the Baccinello-Cinigiano basin (Grosseto, one of the longest and most continuous vertebrate-bearing continental successions in the Neogene Italian record, yielded at least four superimposed vertebrate assemblages bracketed in the time span 8.3 - 6.4 Ma. The Baccinello-Cinigiano basin is famous for recording endemic vertebrate assemblages that include the youngest European Miocene hominoid, Oreopithecus bambolii. The late Miocene endemic vertebrate fauna known as the Baccinello V0 assemblage is the oldest vertebrate fauna within the Baccinello-Cinigiano basin succession, being correlated to the European mammal Neogene unit MN11. Recent field surveys along the Trasubbie river allowed studying in detail the basal Baccinello-Cinigiano sedimentary succession, and sampling fossiliferous level bearing microvertebrates along the small creek Fosso della Fittaia. The sample “Fosso della Fittaia 2013” yielded about 170 fossil remains improving our documentation of the oldest vertebrate assemblages from the Baccinello-Cinigian basin. As far as rodents are concerned, in addition to the already recognized murid Huerzelerimys and glirid Anthracoglis, a few dental remains are assigned to a new genus and species of giant dormouse. It is further worth noting the occurrence in the sample of shrew remains (the first described from the Baccinello-Cinigiano basin identified as cf. Lartetium. The latter attests the presence of a crocidosoricine in the Fosso della Fittaia 2013 assemblage, postdating the youngest known occurrences of the subfamily by at least 1 my. The vertebrate assemblage is completed by a diverse herpetofauna and the first fish remains reported from the basin.

  8. Continental emergence in the Late Archean reconciles early and late continental growth models

    Science.gov (United States)

    Flament, Nicolas; Coltice, Nicolas; Rey, Patrice

    2014-05-01

    The analysis of ancient sediments (Rare Earth Element composition of black shales, isotopic strontium composition of marine carbonates, isotopic oxygen composition of zircons) suggests that continental growth culminated around the Archean-Proterozoic transition. In stark contrast, the geochemical analysis of ancient basalts suggests that depletion of the mantle occurred in the Hadean and Eoarchean. This paradox may be solved if continents were extracted from the mantle early in Earth's history, but remained mostly below sea level throughout the Archean. We present a model to estimate the area of emerged land and associated isotopic strontium composition of the mantle and oceans as a function of the coupled evolution of mantle temperature, continental growth and distribution of surface elevations (hypsometry). For constant continental hypsometry and four distinct continental growth models, we show that sea level was between 500 and 2000 m higher in the Archean than at present, resulting in isotopic composition of the mantle and oceans, we show that a reduced area of emerged continental crust can explain why the geochemical fingerprint of continents extracted early in Earth's history was not recorded at the surface of the Earth until the late Archean.

  9. Climate change effects on an endemic-rich edaphic flora: resurveying Robert H. Whittaker's Siskiyou sites (Oregon, USA)

    Science.gov (United States)

    Damschen, Ellen Ingman; Harrison, Susan; Grace, James B.

    2010-01-01

    Species with relatively narrow niches, such as plants restricted (endemic) to particular soils, may be especially vulnerable to extinction under a changing climate due to the enhanced difficulty they face in migrating to suitable new sites. To test for community-level effects of climate change, and to compare such effects in a highly endemic-rich flora on unproductive serpentine soils vs. the flora of normal (diorite) soils, in 2007 we resampled as closely as possible 108 sites originally studied by ecologist Robert H. Whittaker from 1949 to 1951 in the Siskiyou Mountains of southern Oregon, USA. We found sharp declines in herb cover and richness on both serpentine and diorite soils. Declines were strongest in species of northern biogeographic affinity, species endemic to the region (in serpentine communities only), and species endemic to serpentine soils. Consistent with climatic warming, herb communities have shifted from 1949-1951 to 2007 to more closely resemble communities found on xeric (warm, dry) south-facing slopes. The changes found in the Siskiyou herb flora suggest that biotas rich in narrowly distributed endemics may be particularly susceptible to the effects of a warming climate.

  10. Climate change effects on an endemic-rich edaphic flora: resurveying Robert H. Whittaker's Siskiyou sites (Oregon, USA).

    Science.gov (United States)

    Damschen, Ellen I; Harrison, Susan; Grace, James B

    2010-12-01

    Species with relatively narrow niches, such as plants restricted (endemic) to particular soils, may be especially vulnerable to extinction under a changing climate due to the enhanced difficulty they face in migrating to suitable new sites. To test for community-level effects of climate change, and to compare such effects in a highly endemic-rich flora on unproductive serpentine soils vs. the flora of normal (diorite) soils, in 2007 we resampled as closely as possible 108 sites originally studied by ecologist Robert H. Whittaker from 1949 to 1951 in the Siskiyou Mountains of southern Oregon, USA. We found sharp declines in herb cover and richness on both serpentine and diorite soils. Declines were strongest in species of northern biogeographic affinity, species endemic to the region (in serpentine communities only), and species endemic to serpentine soils. Consistent with climatic warming, herb communities have shifted from 1949-1951 to 2007 to more closely resemble communities found on xeric (warm, dry) south-facing slopes. The changes found in the Siskiyou herb flora suggest that biotas rich in narrowly distributed endemics may be particularly susceptible to the effects of a warming climate.

  11. The petroleum resources on the Norwegian continental shelf. 2007

    Energy Technology Data Exchange (ETDEWEB)

    2007-07-01

    The petroleum resources will not last for ever. It is therefore important for Norway to look ahead so as to be prepared for the changes that will come. In this report, the Norwegian Petroleum Directorate presents the current status of the petroleum resources on the Norwegian continental shelf. This is the basis on which the authorities can lay plans for the future. Since no-one can predict the future with certainty, on this occasion the Directorate is presenting four alternative scenarios for the future of Norwegian petroleum activities if the basic scenario proves incorrect. This will enable us to prepare ourselves for changes that may come, and to view the consequences of the various choices we can make. In this report, the Directorate also describes the various plays on the continental shelf, and explains the techniques used and the evaluations made when it estimates the undiscovered resources. This information is important for exploration work, particularly for new companies which need to get acquainted with the geology and the possibilities for finding oil and gas in Norway. Significant volumes remain to be produced and found on the Norwegian continental shelf. Only a third of the total resources have so far been produced, and a quarter of them have still not been discovered. Oil and gas prices are high at the moment, giving the industry and society in general good incentives to produce at a maximum rate. Oil production reached its peak a couple of years ago, but gas production is still increasing. However, the industry is finding less than it produces, which places demands on both it and the authorities. The industry must actively explore the acreage it has been allocated. The Petroleum Directorate believes that substantial resources can still be discovered in areas where production licences have been awarded. At the same time, the industry must gain access to new areas for exploration. The authorities must find an appropriate balance between concern for the

  12. Basins in ARC-continental collisions

    Science.gov (United States)

    Draut, Amy E.; Clift, Peter D.; Busby, Cathy; Azor, Antonio

    2012-01-01

    Arc-continent collisions occur commonly in the plate-tectonic cycle and result in rapidly formed and rapidly collapsing orogens, often spanning just 5-15 My. Growth of continental masses through arc-continent collision is widely thought to be a major process governing the structural and geochemical evolution of the continental crust over geologic time. Collisions of intra-oceanic arcs with passive continental margins (a situation in which the arc, on the upper plate, faces the continent) involve a substantially different geometry than collisions of intra-oceanic arcs with active continental margins (a situation requiring more than one convergence zone and in which the arc, on the lower plate, backs into the continent), with variable preservation potential for basins in each case. Substantial differences also occur between trench and forearc evolution in tectonically erosive versus tectonically accreting margins, both before and after collision. We examine the evolution of trenches, trench-slope basins, forearc basins, intra-arc basins, and backarc basins during arc-continent collision. The preservation potential of trench-slope basins is low; in collision they are rapidly uplifted and eroded, and at erosive margins they are progressively destroyed by subduction erosion. Post-collisional preservation of trench sediment and trench-slope basins is biased toward margins that were tectonically accreting for a substantial length of time before collision. Forearc basins in erosive margins are usually floored by strong lithosphere and may survive collision with a passive margin, sometimes continuing sedimentation throughout collision and orogeny. The low flexural rigidity of intra-arc basins makes them deep and, if preserved, potentially long records of arc and collisional tectonism. Backarc basins, in contrast, are typically subducted and their sediment either lost or preserved only as fragments in melange sequences. A substantial proportion of the sediment derived from

  13. New Tracers of Gas Migration in the Continental Crust

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, Mark D. [Woods Hole Oceanographic Inst., MA (United States)

    2015-11-01

    Noble gases are exceptional tracers in continental settings due to the remarkable isotopic variability between the mantle, crust, and atmosphere, and because they are inert. Due to systematic variability in physical properties, such as diffusion, solubility, and production rates, the combination of helium, neon, and argon provides unique but under-utilized indices of gas migration. Existing noble gas data sets are dominated by measurements of gas and fluid phases from gas wells, ground waters and hot springs. There are very few noble gas measurements from the solid continental crust itself, which means that this important reservoir is poorly characterized. The central goal of this project was to enhance understanding of gas distribution and migration in the continental crust using new measurements of noble gases in whole rocks and minerals from existing continental drill cores, with an emphasis on helium, neon, argon. We carried out whole-rock and mineral-separate noble gas measurements on Precambrian basement samples from the Texas Panhandle. The Texas Panhandle gas field is the southern limb of the giant Hugoton-Panhandle oil and gas field; it has high helium contents (up to ~ 2 %) and 3He/4He of 0.21 (± 0.03) Ra. Because the total amount of helium in the Panhandle gas field is relatively well known, crustal isotopic data and mass balance calculations can be used to constrain the ultimate source rocks, and hence the helium migration paths. The new 3He/4He data range from 0.03 to 0.11 Ra (total), all of which are lower than the gas field values. There is internal isotopic heterogeneity in helium, neon, and argon, within all the samples; crushing extractions yield less radiogenic values than melting, demonstrating that fluid inclusions preserve less radiogenic gases. The new data suggest that the Precambrian basement has lost significant amounts of helium, and shows the importance of measuring helium with neon and argon. The 4He/40Ar values are particularly useful

  14. The character of the glaciated Mid-Norwegian continental margin

    Science.gov (United States)

    Oline Hjelstuen, Berit; Haflidason, Haflidi; Petter Sejrup, Hans

    2010-05-01

    During Pleistocene the development of the NW European continental margin was strongly controlled by the variability in ocean circulation, glaciations and sea-level changes. Repeated occurrence of shelf edge glaciations, from Ireland to Svalbard, started at Marine Isotope Stage 12 (c. 0.5 Ma). During these periods, fast moving ice streams also crossed the Mid-Norwegian continental shelf on a number of locations, and a thick prograding wedge accumulated on the continental slope. During shelf edge glaciations and in early deglaciation phases high sedimentation rates (>2000 cm/ka) existed, and glacigenic debris flows and melt water plumes were deposited. Within these depositional environments we identify three slide events. These slides have affected an area between 2900 and 12000 km2 and involved 580-2400 km3 of sediments, noting that the slide debrites left by the failure events reach a maximum thickness of c. 150 m. The failures have occurred within an area dominated by gradients less than 1 degree, and observation of long run-out distances indicate that hydroplaning was important during slide development. Gas hydrate bearing sediments are identified on the mid-Norwegian continental margin, but appears to be absent in the slide scars. Thus, dissociation of gas hydrates may have promoted conditions for the failures to occur. Within the region of gas hydrate bearing Pleistocene sediments the Nyegga Pockmark Field is observed. This field contains more than 200 pockmarks and is located at a water depth of 600-800 m. The pockmarks identified are up to 15 m deep, between 30 m and 600 m across and reach a maximum area of c. 315 000 m2. The pockmarks are sediment-empty features and are restricted to a <16.2 cal ka BP old sandy mud unit. It seems that the Nyegga Pockmark Field does not show any strong relationship neither to seabed features, sub-seabed structures nor the glacial sedimentary setting. Thus, this implies a more complex development history for the Nyegga

  15. Reconstructing Rodinia by Fitting Neoproterozoic Continental Margins

    Science.gov (United States)

    Stewart, John H.

    2009-01-01

    Reconstructions of Phanerozoic tectonic plates can be closely constrained by lithologic correlations across conjugate margins by paleontologic information, by correlation of orogenic belts, by paleomagnetic location of continents, and by ocean floor magmatic stripes. In contrast, Proterozoic reconstructions are hindered by the lack of some of these tools or the lack of their precision. To overcome some of these difficulties, this report focuses on a different method of reconstruction, namely the use of the shape of continents to assemble the supercontinent of Rodinia, much like a jigsaw puzzle. Compared to the vast amount of information available for Phanerozoic systems, such a limited approach for Proterozoic rocks, may seem suspect. However, using the assembly of the southern continents (South America, Africa, India, Arabia, Antarctica, and Australia) as an example, a very tight fit of the continents is apparent and illustrates the power of the jigsaw puzzle method. This report focuses on Neoproterozoic rocks, which are shown on two new detailed geologic maps that constitute the backbone of the study. The report also describes the Neoproterozoic, but younger or older rocks are not discussed or not discussed in detail. The Neoproterozoic continents and continental margins are identified based on the distribution of continental-margin sedimentary and magmatic rocks that define the break-up margins of Rodinia. These Neoproterozoic continental exposures, as well as critical Neo- and Meso-Neoproterozoic tectonic features shown on the two new map compilations, are used to reconstruct the Mesoproterozoic supercontinent of Rodinia. This approach differs from the common approach of using fold belts to define structural features deemed important in the Rodinian reconstruction. Fold belts are difficult to date, and many are significantly younger than the time frame considered here (1,200 to 850 Ma). Identifying Neoproterozoic continental margins, which are primarily

  16. Prioritization of malaria endemic zones using self-organizing maps in the Manipur state of India.

    Science.gov (United States)

    Murty, Upadhyayula Suryanarayana; Srinivasa Rao, Mutheneni; Misra, Sunil

    2008-09-01

    Due to the availability of a huge amount of epidemiological and public health data that require analysis and interpretation by using appropriate mathematical tools to support the existing method to control the mosquito and mosquito-borne diseases in a more effective way, data-mining tools are used to make sense from the chaos. Using data-mining tools, one can develop predictive models, patterns, association rules, and clusters of diseases, which can help the decision-makers in controlling the diseases. This paper mainly focuses on the applications of data-mining tools that have been used for the first time to prioritize the malaria endemic regions in Manipur state by using Self Organizing Maps (SOM). The SOM results (in two-dimensional images called Kohonen maps) clearly show the visual classification of malaria endemic zones into high, medium and low in the different districts of Manipur, and will be discussed in the paper.

  17. Study on the sources of endemic fluorosis in Weixin, Yunnan Province, China

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, G.; Tian, J.; Qin, Y. [Chengdu University of Technology, Chengdu (China). Institute of Sedimentary Geology

    2007-03-15

    The sources of endemic fluorosis in Weixin, Zhaotong of Yunnan Province has been studied using ion selective electrode (ISE) and X-ray diffraction analysis (XRD). The results show that the main workable channel coal seams contain an average fluorine content of 67.8 x 10{sup -6}, which is much lower than that of Chinese and American common coals. The contents in the clay and the mixture of coal and clay reach to 2239 x 10{sup -6} and 863.3 x 10{sup -6}, respectively. (The mixture of clay and coal is the primary fuel in the local families.) The volatile yield of the mixture of coal and clay during combustion is about 89%. The fluorine in the clay is the main source of the endemic fluorosis. The high content of fluorine is closely related to the mixed-layer minerals of illite and smectite, apatite, hornblende, and K-feldspar. 19 refs., 3 tabs.

  18. Incipient speciation with gene flow on a continental island: Species delimitation of the Hainan Hwamei (Leucodioptron canorum owstoni, Passeriformes, Aves).

    Science.gov (United States)

    Wang, Ning; Liang, Bin; Wang, Jichao; Yeh, Chia-Fen; Liu, Yang; Liu, Yanlin; Liang, Wei; Yao, Cheng-Te; Li, Shou-Hsien

    2016-09-01

    Because of their isolation, continental islands (e.g., Madagascar) are often thought of as ideal systems to study allopatric speciation. However, many such islands have been connected intermittently to their neighboring continent during recent periods of glaciation, which may cause frequent contact between the diverging populations on the island and continent. As a result, the speciation processes on continental islands may not meet the prerequisites for strictly allopatric speciation. We used multiple lines of evidence to re-evaluate the taxonomic status of the Hainan Hwamei (Leucodioptron canorum owstoni), which is endemic to Hainan, the largest continental island in the South China Sea. Our analysis of mitochondrial DNA and twelve nuclear loci suggests that the Hainan Hwamei can be regarded as an independent species (L. owstoni); the morphological traits of the Hainan Hwamei also showed significant divergence from those of their mainland sister taxon, the Chinese Hwamei (L. canorum). We also inferred the divergence history of the Hainan and Chinese Hwamei to see whether their divergence was consistent with a strictly allopatric model. Our results suggest that the two Hwameis split only 0.2 million years ago with limited asymmetrical post-divergence gene flow. This implies that the Hainan Hwamei is an incipient species and that speciation occurred through ecologically divergent selection and/or assortative mating rather than a strictly allopatric process.

  19. Antibody responses to Rhoptry-Associated Protein-1 (RAP-1) of Plasmodium falciparum parasites in humans from areas of different malaria endemicity

    DEFF Research Database (Denmark)

    Jakobsen, P H; Kurtzhals, J A; Riley, E M

    1997-01-01

    Plasma IgM and IgG antibody reactivities against the recombinant Plasmodium falciparum protein, Rhoptry Associated Protein-1 (rRAP-1) were measured by ELISA in individuals from Sudan, Indonesia, Kenya and The Gambia living in areas of different malaria endemicity. IgG and IgM reactivities to rRAP-1...... increased with malaria endemicity. IgG reactivities were associated with spleen rates in Indonesia with high malaria endemicity while IgM reactivities were associated with spleen rates in Kenya with low malaria endemicity. IgG and IgM reactivities to rRAP-1 increased during acute episodes of P. falciparum...... malaria in Sudanese adults and IgG reactivities remained high one month after treatment in all adults tested. Antibody reactivities to rRAP-1 in Gambian children in the dry season were higher in children with parasitaemia than in children without detectable parasitaemia. Antibody reactivities were...

  20. [Malaria serology test: what contribution does it make in an endemic country such as Ivory Coast?

    Science.gov (United States)

    Goran-Kouacou, Amah Patricia Victorine; Dou, Gonat Serge; Zika, Kalou Dibert; Adou, Adjoumanvoulé Honoré; Yéboah, Oppong Richard; Aka, Rita Ahou; Hien, Sansan; Siransy, Kouabla Liliane; N'Guessan, Koffi; Djibangar, Tariam Agnès; Dassé, Séry Romuald; Adoubryn, Koffi Daho

    2017-01-01

    Malaria serology test seems to have attracted very little interest in endemic countries such as Ivory Coast. However, this examination has been regularly performed in the parasitology laboratory at the Training and Research Unit of Medical Sciences in Abidjan. Our study aimed to highlight the contribution of malaria serology test in our endemic country context. We conducted a retrospective study of malaria serology test using Falciparum-Spot IF (bioMerieux) kit for the detection of IgG antiplasmodial antibodies. It included all malaria serology tests performed from January 2007 to February 2011 and whose results were available in the registry. In total, 136 patients were selected. The average age of patients was 36,3 years, ranging from 1 to 81 years, and sex ratio was 0,97. Indications for malaria serology test were varied and dominated by splenomegaly (49.3%), cytopenias (14.7%), indeterminate fever (13.2%). Almost all of the patients (98.5%) had antiplasmodial antibodies with high medium titer of 1057,35IU/ml. There was no link between age and Ab titer, which was higher in cytopenias, prolonged fevers and the splenomegaly. Malaria serology test seems to have attracted very little interest in routine clinical practice provided in our endemic area because, whatever the reason of the prescription, titers were high.

  1. Bird communities in three forest types in the Pernambuco Centre of Endemism, Alagoas, Brazil

    Directory of Open Access Journals (Sweden)

    Lahert W. Lobo-Araújo

    2013-06-01

    Full Text Available The Pernambuco Center of Endemism (PCE in northeastern Brazil is highly fragmented and degraded. Despite its potential conservation importance the bird fauna in this area is still relatively unknown and there are many remnant fragments that have not been systematically surveyed. Here, we report the results of bird surveys in five forest fragments (one pioneer, two ombrophilous and two seasonal. In total, 162 taxa were recorded, 12 of which are endemic to the PCE. The frequency of endangered species was lower than what has been reported in studies from the same area and most of the taxa considered to be at risk of extinction were sub-species of uncertain taxonomic validity. The comparatively low number of endemic/threatened species may be due to the small size of the fragments in the present study - a consequence of the high levels of habitat loss in this region. Analysis of species richness patterns indicates that ombrophilous forest fragments are acting as refuges for those bird species that are most sensitive to environmental degradation.

  2. Development of topography in 3-D continental-collision models

    Science.gov (United States)

    Pusok, A. E.; Kaus, Boris J. P.

    2015-05-01

    Understanding the formation and evolution of high mountain belts, such as the Himalayas and the adjacent Tibetan Plateau, has been the focus of many tectonic and numerical models. Here we employ 3-D numerical simulations to investigate the role that subduction, collision, and indentation play on lithosphere dynamics at convergent margins, and to analyze the conditions under which large topographic plateaus can form in an integrated lithospheric and upper mantle-scale model. Distinct dynamics are obtained for the oceanic subduction side (trench retreat, slab rollback) and the continental-collision side (trench advance, slab detachment, topographic uplift, lateral extrusion). We show that slab pull alone is insufficient to generate high topography in the upper plate, and that external forcing and the presence of strong blocks such as the Tarim Basin are necessary to create and shape anomalously high topographic fronts and plateaus. Moreover, scaling is used to predict four different modes of surface expression in continental-collision models: (I) low-amplitude homogeneous shortening, (II) high-amplitude homogeneous shortening, (III) Alpine-type topography with topographic front and low plateau, and (IV) Tibet-Himalaya-type topography with topographic front and high plateau. Results of semianalytical models suggest that the Argand number governs the formation of high topographic fronts, while the amplitude of plateaus is controlled by the initial buoyancy ratio of the upper plate. Applying these results to natural examples, we show that the Alps belong to regime (III), the Himalaya-Tibet to regime (IV), whereas the Andes-Altiplano fall at the boundary between regimes (III) and (IV).

  3. Comparative Evaluation of Tubex TF (Inhibition Magnetic Binding Immunoassay) for Typhoid Fever in Endemic Area.

    Science.gov (United States)

    Khanna, Ashish; Khanna, Menka; Gill, Karamjit Singh

    2015-11-01

    Typhoid fever remains a significant health problem in endemic countries like India. Various serological tests for the diagnosis of typhoid fever are available commercially. We assessed the usefulness of rapid test based on magnetic particle separation to detect Immunoglobulin against Salmonella typhi O9 lipopolysaccharide. Aim of this study was to compare the sensitivity and specificity of widal test, typhidot and tubex TF test for the diagnosis of typhoid fever in an endemic country like India. Serum samples collected from 50 patients of typhoid fever, 50 patients of non typhoid fever and 100 normal healthy individuals residing in Amritsar were subjected to widal test, typhidot test and tubex TF test as per manufacturer's instructions. Data collected was assessed to find sensitivity and specificity of these tests in an endemic area. Significant widal test results were found positive in 68% of patients of typhoid fever and only 4% of non typhoid fever patients. Typhidot (IgM or IgG) was positive in 72% of typhoid fever patients and 10% and 6% in non typhoid fever and normal healthy individuals respectively. Tubex TF showed higher sensitivity of 76% and specificity of 96-99% which was higher than typhidot and comparable to widal test. This was the first evaluation of rapid tubex TF test in northern India. In countries which can afford high cost of test, tubex TF should be recommended for the diagnosis in acute stage of the disease in clinical setting. However, there is urgent need for a highly specific and sensitive test for the diagnosis of typhoid fever in clinical settings in endemic areas.

  4. Medical geology of endemic goiter in Kalutara, Sri Lanka; distribution and possible causes.

    Science.gov (United States)

    Fernando, G W A R; Liyanage, P L C L; Rajapaksha, Anushka Upamali; Vithanage, Meththika

    2017-05-27

    This study assesses the distribution of goiter in the Kalutara District, Sri Lanka in order to find causative factors for the occurrence of goiter even after the salt iodization. A questionnaire survey was conducted at the household level and at the same time iodine and selenium levels of the water sources were analyzed. Questionnaire survey results indicated the highest numbers of goiter patients in the northern part where the lowest were found in the southern sector which may be due to the presence of acid sulfate soils. Females were more susceptible and it even showed a transmittance between generations. Average iodine concentrations in subsurface water of goiter endemic regions are 28.25 ± 15.47 μg/L whereas non-goiter regions show identical values at 24.74 ± 18.29 μg/L. Surface water exhibited relatively high values at 30.87 ± 16.13 μg/L. Endemic goiter was reported in some isolated patches where iodine and selenium concentrations low, latter was <10 μg/L. The formation of acid sulfate soils in the marshy lands in Kalutara district may lead to transformation of biological available iodine oxidation into volatile iodine by humic substances, at the same time organic matter rich peaty soil may have strong held of iodine and selenium which again induced by low pH and high temperature were suggested as the instrumental factors in the endemic goiter in Kalutara district. Hence, geochemical features such as soil pH, organic matter and thick lateritic cap in the Kalutara goiter endemic area play a role in controlling the available selenium and iodine for food chain through plant uptake and in water.

  5. Provenance and geochemical behavior of fluorine in the soils of an endemic fluorosis belt, central Iran

    Science.gov (United States)

    Dehbandi, Reza; Moore, Farid; Keshavarzi, Behnam

    2017-05-01

    The concentration of fluorine, major, trace and rare earth elements (REEs) were used to estimate the probable sources and provenance of fluorine in the soils of an endemic fluorosis belt in central Iran. Total fluorine (TF) in soils varied from 146 to 406 mg/kg with a mean of 277.5 mg/kg. Calculated enrichment factor (EF) and single factor pollution index (SFPI) revealed that the majority of soil samples were moderately contaminated by fluorine. The very strong positive correlation of TF with weathering indices and soil's fine sized fractions indicated that chemical weathering and alteration of parent rocks/soils are the main controlling factors of fluorine behavior in soils. Fluorine affinity to immobile transition trace elements and REEs suggested the role of heavy minerals as the potential F host phases. Modal mineralogy along with SEM-EDX analysis indicated that apatite, fluorapophyllite, epidote, biotite, muscovite and chlorite, as well as, clay minerals are the main F-bearing minerals in the studied soils. Discriminant, bivariate and ternary diagrams of elemental compositions displayed similar geochemical signature of soils to intermediate-acidic rocks and local shales. Based on the weathering indices, soils were immature and showed a non-steady state weathering trend from upper continental crust (UCC), acidic and intermediate igneous source rocks towards shale composition possibly due to mixing of moderately weathered and un-weathered sources of different primary compositions.

  6. Granitic Perspectives on the Generation and Secular Evolution of the Continental Crust

    Science.gov (United States)

    Kemp, A. I. S.; Hawkesworth, C. J.

    2003-12-01

    Every geologist is acquainted with the principle of "uniformitarianism," which holds that present-day processes are the key to those that operated in the past. But the extent this applies to the processes driving the growth and differentiation of the Earth's continental crust remains a matter of debate. Unlike its dense oceanic counterpart, which is recycled back into the mantle by subduction within 200 Ma (see Chapter 3.13), the continental crust comprises buoyant quartzofeldspathic materials and is difficult to destroy by subduction. The continental crust is, therefore, the principal record of how conditions on the Earth have changed, and how processes of crust generation have evolved through geological time. It preserves evidence of secular variation in crustal compositions, and thus the way in which the crust has formed throughout Earth's history. Exploring the nature and origin of these variations is the focus of this chapter.Continental rocks are highly differentiated, and so the crust is enriched in incompatible components compared to the primeval chondritic composition (see Chapter 3.01). Of these, water is perhaps the most relevant, both for the origin and evolution of life, and also for many models of crust generation and differentiation. Similarly, the mass of continental crust is just 0.57% of the silicate Earth, and yet it contains ˜35% of the potassium (using the crustal composition estimates in Table 1). Continental rocks comprise the buoyant shell that was once thought to float on a basaltic substratum, inferred from the wide distribution of chemically similar continental flood basalts (von Cotta, 1858). The links with the adjacent oceans were perhaps unclear, "the greatest mountains confront the widest oceans" ( Dana, 1873). Yet, it has long been argued that the rock that has the most similar composition to the average continental crust, andesite, may be generated by fractional crystallization of basalt ( Daly (1914) and Bowen (1928); but see the

  7. The continental margin is a key source of iron to the HNLC North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Lam, P.J.; Bishop, J.K.B

    2008-01-15

    Here we show that labile particulate iron and manganese concentrations in the upper 500m of the Western Subarctic Pacific, an iron-limited High Nutrient Low Chlorophyll (HNLC) region, have prominent subsurface maxima between 100-200 m, reaching 3 nM and 600 pM, respectively. The subsurface concentration maxima in particulate Fe are characterized by a more reduced oxidation state, suggesting a source from primary volcagenic minerals such as from the Kuril/Kamchatka margin. The systematics of these profiles suggest a consistently strong lateral advection of labile Mn and Fe from redox-mobilized labile sources at the continental shelf supplemented by a more variable source of Fe from the upper continental slope. This subsurface supply of iron from the continental margin is shallow enough to be accessible to the surface through winter upwelling and vertical mixing, and is likely a key source of bioavailable Fe to the HNLC North Pacific.

  8. The endemic plants of Micronesia: a geographical checklist and commentary

    Directory of Open Access Journals (Sweden)

    Lorence, D.H.

    2012-05-01

    Full Text Available The Micronesia-Polynesia bioregion is recognized as a global biodiversity hotspot. However, until now estimates regarding the number of endemic plant species for the region were not supported by any comprehensive published work for the region. The results of this study indicate that Micronesia has the world’s highest percentage of plant endemism per square kilometer out of all globally recognized insular biodiversity hotspots. A checklist of all endemic plant species for Micronesia is presented here with their corresponding geographical limits within the region. A summary of previous work and estimates is also provided noting the degree of taxonomic progress in the past several decades. A total of 364 vascular plant species are considered endemic to Micronesia, most of them being restricted to the Caroline Islands with a large percentage restricted to Palau. The checklist includes seven new combinations, one new name, and two unverified names that require additional study to verify endemic status. Overviews of each respective botanical family represented in the list are given including additional information on the Micronesian taxa. Recommendations for future work and potential projects are alluded to throughout the text highlighting major data gaps and very poorly known taxa. The following new combinations and names are made: Cyclosorus carolinensis (Hosokawa Lorence, comb. nov. , Cyclosorusgretheri (W. H. Wagner Lorence, comb. nov., Cyclosorusguamensis (Holttum Lorence, comb. nov., Cyclosorus palauensis (Hosokawa Lorence, comb. nov. , Cyclosorus rupiinsularis (Fosberg Lorence, comb. nov., Dalbergia hosokawae (Hosokawa Costion nom. nov., Syzygium trukensis (Hosokawa Costion & E. Lucas comb. nov.

  9. Environmental renal disease: Lead, cadmium and Balkan endemic nephropathy

    Energy Technology Data Exchange (ETDEWEB)

    Wedeen, R.P. (VA Medical Center, East Orange, NJ (United States))

    1991-11-01

    The similarity of lead and cadmium nephropathy to Balkan endemic nephropathy warrants careful reevaluation of the possibility that these nephrotoxic metals contribute to the production of the endemic renal disease. Low-level environmental exposure may result in a relationship between the concentration of the metals in tissue storage sites and biological fluids that differs from that encountered after occupational exposure. Urine and blood concentrations may therefore be inadequate measures of exposure. Lead is accumulated in the skeleton and cadmium in the liver and kidneys with biological half lives approximating a decade. Non-invasive in vivo x-ray fluorescence or neutron activation analysis can therefore be used to measure cumulative tissue stores. Multiple regression analysis of epidemiologic data could reveal the relative contribution of causal factors, including lead and cadmium, and help to distinguish Balkan endemic nephropathy from other renal diseases using rigorous diagnostic criteria. As long as Balkan endemic nephropathy remains a diagnosis of exclusion, the accuracy of the diagnosis of other renal disease determines the reliability of identification of the endemic disease.31 references.

  10. The geography of imported malaria to non-endemic countries: a meta-analysis of nationally reported statistics.

    Science.gov (United States)

    Tatem, Andrew J; Jia, Peng; Ordanovich, Dariya; Falkner, Michael; Huang, Zhuojie; Howes, Rosalind; Hay, Simon I; Gething, Peter W; Smith, David L

    2017-01-01

    Malaria remains a problem for many countries classified as malaria free through cases imported from endemic regions. Imported cases to non-endemic countries often result in delays in diagnosis, are expensive to treat, and can sometimes cause secondary local transmission. The movement of malaria in endemic countries has also contributed to the spread of drug resistance and threatens long-term eradication goals. Here we focused on quantifying the international movements of malaria to improve our understanding of these phenomena and facilitate the design of mitigation strategies. In this meta-analysis, we studied the database of publicly available nationally reported statistics on imported malaria in the past 10 years, covering more than 50 000 individual cases. We obtained data from 40 non-endemic countries and recorded the geographical variations. Infection movements were strongly skewed towards a small number of high-traffic routes between 2005 and 2015, with the west Africa region accounting for 56% (13 947/24 941) of all imported cases to non-endemic countries with a reported travel destination, and France and the UK receiving the highest number of cases, with more than 4000 reported cases per year on average. Countries strongly linked by movements of imported cases are grouped by historical, language, and travel ties. There is strong spatial clustering of plasmodium species types. The architecture of the air network, historical ties, demographics of travellers, and malaria endemicity contribute to highly heterogeneous patterns of numbers, routes, and species compositions of parasites transported. With global malaria eradication on the international agenda, malaria control altering local transmission, and the threat of drug resistance, understanding these patterns and their drivers is increasing in importance. Bill & Melinda Gates Foundation, National Institutes of Health, UK Medical Research Council, UK Department for International Development, Wellcome

  11. The holocene sequence of the central continental shelf of the State of Bahia, Brazil; A sequencia holocenica da plataforma continental central do Estado da Bahia

    Energy Technology Data Exchange (ETDEWEB)

    Freire, Antonio Fernando Menezes; Dominguez, Jose Maria Landim [PETROBRAS S.A., BA (Brazil). Unidade de Negocios de Exploracao e Producao da Bahia. Ativo de Exploracao Avaliacao e Acompanhamento Geologico]. E-mail: fernandofreire@petrobras.com.br

    2006-05-15

    Fifty cores were recovered from the sea bottom in the central portion of the continental shelf of the State of Bahia, between the Marau Peninsula and the city of Olivenca. Thirty six of these cores were collected by divers at up to 40 m deep waters. Fourteen cores were collected by piston cores in areas ranging from the continental shelf to the upper slope. All cores were described, photographed and sampled for grain size and bio stratigraphic analysis. These data were used to prepare textural and facies maps of the continental shelf. The piston cores were run parallel to sub-bottom profiling surveys. Results show that there is a strong reflector located 3 - 4 m below the sediment- water interface, which limited the penetration of the piston cores. This reflector represents a sequence boundary separating the holocene from the pleistocene sequences. A transgressive system tract has been deposited on the top of this surface along with the early stages of the high stand system tract, particularly on the inner shelf. Because of the starved character of this shelf, notably on its external portion, a detailed application of sequence stratigraphy concepts has not been possible. Only at the inner shelf/shore face there is evident pro gradation of siliciclastics over carbonates. Several submarine valleys dissect the outer shelf/upper slope, thus acting as channels that transport continental shelf sediments to the deeper portions of the basin. (author)

  12. A 22-Year Survey of Leishmaniasis Cases in a Tertiary-Care Hospital in an Endemic Setting

    Directory of Open Access Journals (Sweden)

    Adriana Calderaro

    2014-03-01

    Full Text Available The northward spread of leishmaniasis from Mediterranean to Continental Europe affects our area where it is typically associated with Leishmania infantum infection. In this study a 22-year survey was performed in patients (including both patients with and without history of travel through endemic areas other than Italy attending the University Hospital of Parma, Northern Italy, in order to make a contribution to describe the cases of the visceral leishmaniasis (VL and cutaneous leishmaniasis (CL diagnosed in this area. One hundred fifty-six samples from 134 patients with clinical suspicion of leishmaniasis (96 suspected of having VL, 37 CL and one both VL and CL were analyzed in our laboratory during 1992–2013 by microscopy, culture and, from 2005, also by real-time PCR. Leishmania spp. were detected in 23 samples of 15 patients (seven with VL and eight with CL, representing an infection rate of 11.2%. The figure of the cases of leishmaniasis herein reported, even if not comparable to that described for Italian areas other than Parma, underlines that suitable tools are mandatory for correct diagnosis. Moreover, the severity of this disease, particularly VL with its documented northward spread, requires physicians of continental Europe to increase their attention about the possibility of suspecting leishmaniasis in patients reporting related signs and symptoms and/or risk factors.

  13. CSDP: Seismology of continental thermal regime

    Energy Technology Data Exchange (ETDEWEB)

    Aki, K.

    1989-04-01

    This is a progress report for the past one year of research (year 2 of 5-year project) under the project titled CSDP: Seismology of Continental Thermal Regime'', in which we proposed to develop seismological interpretation theory and methods applicable to complex structures encountered in continental geothermal areas and apply them to several candidate sites for the Continental Scientific Drilling Project. During the past year, two Ph.D. thesis works were completed under the present project. One is a USC thesis on seismic wave propagation in anisotropic media with application to defining fractures in the earth. The other is a MIT thesis on seismic Q and velocity structure for the magma-hydrothermal system of the Valles Caldera, New Mexico. The P.I. co-organized the first International Workshop on Volcanic Seismology at Capri, Italy in October 1988, and presented the keynote paper on the state-of-art of volcanic seismology''. We presented another paper at the workshop on Assorted Seismic Signals from Kilauea Volcano, Hawaii. Another international meeting, namely, the Chapman Conference on seismic anisotropy in the earth's crust at Berkeley, California in May 1988, was co-organized by the co-P.I. (P.C.L), and we presented our work on seismic waves in heterogeneous and anisotropic media. Adding the publications and presentations made in the past year to the list for the preceding year, the following table lists 21 papers published, submitted or presented in the past two years of the present project. 65 refs., 334 figs., 1 tab.

  14. Fractal behavior in continental crustal heat production

    Directory of Open Access Journals (Sweden)

    N. Vedanti

    2011-02-01

    Full Text Available The distribution of crustal heat production, which is the most important component in the elucidation of continental thermal structure, still remains a theoretical assumption. In general the heat production values must decrease with depth, but the form of decrease of heat production in the crust is not well understood. The commonly used heat production models are: "block model", in which heat production is constant from the surface to a given depth and the "exponential model", in which heat production diminishes as an exponential function of depth. The exponential model is more widely used wherein sources of the errors are heterogeneity of rock and long wavelength changes due to changes in lithology and tectonic elements, and as such exponential distribution does not work satisfactorily for the entire crust. In the present study, we analyze for the first time, deep crustal heat production data of six global areas namely Dharwar craton (India, Kaapvaal craton (South Africa, Baltic shield (Kola, Russia, Hidaka metamorphic belt (Japan, Nissho pluton (Japan and Continental Deep Drilling site (KTB, Germany. The power spectrum of all the studied data sets exhibits power law behaviour. This would mean slower decay of heat production with depth, which conforms to the known geologic composition of the crust. Minimum value of the scaling exponent has been found for the KTB borehole, which is apparently related to higher heat production of gneisses, however for other study areas, scaling exponent is almost similar. We also found that the lower values of scaling exponents are related to higher heat production in the crust as is the case in KTB. Present finding has a direct relevance in computation of temperature-depth profiles in continental regions.

  15. Association of haptoglobin levels with age, parasite density, and haptoglobin genotype in a malaria-endemic area of Gabon.

    NARCIS (Netherlands)

    Fowkes, F.J.; Imrie, H.; Migot-Nabias, F.; Michon, P.; Justice, A.; Deloron, P.; Luty, A.J.F.; Day, K.P.

    2006-01-01

    Haptoglobin (Hp) levels were investigated in relation to host geno